Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1 | /** |
| 2 | * eCryptfs: Linux filesystem encryption layer |
| 3 | * In-kernel key management code. Includes functions to parse and |
| 4 | * write authentication token-related packets with the underlying |
| 5 | * file. |
| 6 | * |
| 7 | * Copyright (C) 2004-2006 International Business Machines Corp. |
| 8 | * Author(s): Michael A. Halcrow <mhalcrow@us.ibm.com> |
| 9 | * Michael C. Thompson <mcthomps@us.ibm.com> |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 10 | * Trevor S. Highland <trevor.highland@gmail.com> |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 11 | * |
| 12 | * This program is free software; you can redistribute it and/or |
| 13 | * modify it under the terms of the GNU General Public License as |
| 14 | * published by the Free Software Foundation; either version 2 of the |
| 15 | * License, or (at your option) any later version. |
| 16 | * |
| 17 | * This program is distributed in the hope that it will be useful, but |
| 18 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 20 | * General Public License for more details. |
| 21 | * |
| 22 | * You should have received a copy of the GNU General Public License |
| 23 | * along with this program; if not, write to the Free Software |
| 24 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA |
| 25 | * 02111-1307, USA. |
| 26 | */ |
| 27 | |
| 28 | #include <linux/string.h> |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 29 | #include <linux/syscalls.h> |
| 30 | #include <linux/pagemap.h> |
| 31 | #include <linux/key.h> |
| 32 | #include <linux/random.h> |
| 33 | #include <linux/crypto.h> |
| 34 | #include <linux/scatterlist.h> |
| 35 | #include "ecryptfs_kernel.h" |
| 36 | |
| 37 | /** |
| 38 | * request_key returned an error instead of a valid key address; |
| 39 | * determine the type of error, make appropriate log entries, and |
| 40 | * return an error code. |
| 41 | */ |
Michael Halcrow | cd9d67d | 2007-10-16 01:28:04 -0700 | [diff] [blame] | 42 | static int process_request_key_err(long err_code) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 43 | { |
| 44 | int rc = 0; |
| 45 | |
| 46 | switch (err_code) { |
Eric Sandeen | 982363c | 2008-07-23 21:30:04 -0700 | [diff] [blame] | 47 | case -ENOKEY: |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 48 | ecryptfs_printk(KERN_WARNING, "No key\n"); |
| 49 | rc = -ENOENT; |
| 50 | break; |
Eric Sandeen | 982363c | 2008-07-23 21:30:04 -0700 | [diff] [blame] | 51 | case -EKEYEXPIRED: |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 52 | ecryptfs_printk(KERN_WARNING, "Key expired\n"); |
| 53 | rc = -ETIME; |
| 54 | break; |
Eric Sandeen | 982363c | 2008-07-23 21:30:04 -0700 | [diff] [blame] | 55 | case -EKEYREVOKED: |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 56 | ecryptfs_printk(KERN_WARNING, "Key revoked\n"); |
| 57 | rc = -EINVAL; |
| 58 | break; |
| 59 | default: |
| 60 | ecryptfs_printk(KERN_WARNING, "Unknown error code: " |
| 61 | "[0x%.16x]\n", err_code); |
| 62 | rc = -EINVAL; |
| 63 | } |
| 64 | return rc; |
| 65 | } |
| 66 | |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 67 | /** |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 68 | * ecryptfs_parse_packet_length |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 69 | * @data: Pointer to memory containing length at offset |
| 70 | * @size: This function writes the decoded size to this memory |
| 71 | * address; zero on error |
| 72 | * @length_size: The number of bytes occupied by the encoded length |
| 73 | * |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 74 | * Returns zero on success; non-zero on error |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 75 | */ |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 76 | int ecryptfs_parse_packet_length(unsigned char *data, size_t *size, |
| 77 | size_t *length_size) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 78 | { |
| 79 | int rc = 0; |
| 80 | |
| 81 | (*length_size) = 0; |
| 82 | (*size) = 0; |
| 83 | if (data[0] < 192) { |
| 84 | /* One-byte length */ |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 85 | (*size) = (unsigned char)data[0]; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 86 | (*length_size) = 1; |
| 87 | } else if (data[0] < 224) { |
| 88 | /* Two-byte length */ |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 89 | (*size) = (((unsigned char)(data[0]) - 192) * 256); |
| 90 | (*size) += ((unsigned char)(data[1]) + 192); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 91 | (*length_size) = 2; |
| 92 | } else if (data[0] == 255) { |
| 93 | /* Five-byte length; we're not supposed to see this */ |
| 94 | ecryptfs_printk(KERN_ERR, "Five-byte packet length not " |
| 95 | "supported\n"); |
| 96 | rc = -EINVAL; |
| 97 | goto out; |
| 98 | } else { |
| 99 | ecryptfs_printk(KERN_ERR, "Error parsing packet length\n"); |
| 100 | rc = -EINVAL; |
| 101 | goto out; |
| 102 | } |
| 103 | out: |
| 104 | return rc; |
| 105 | } |
| 106 | |
| 107 | /** |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 108 | * ecryptfs_write_packet_length |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 109 | * @dest: The byte array target into which to write the length. Must |
| 110 | * have at least 5 bytes allocated. |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 111 | * @size: The length to write. |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 112 | * @packet_size_length: The number of bytes used to encode the packet |
| 113 | * length is written to this address. |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 114 | * |
| 115 | * Returns zero on success; non-zero on error. |
| 116 | */ |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 117 | int ecryptfs_write_packet_length(char *dest, size_t size, |
| 118 | size_t *packet_size_length) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 119 | { |
| 120 | int rc = 0; |
| 121 | |
| 122 | if (size < 192) { |
| 123 | dest[0] = size; |
| 124 | (*packet_size_length) = 1; |
| 125 | } else if (size < 65536) { |
| 126 | dest[0] = (((size - 192) / 256) + 192); |
| 127 | dest[1] = ((size - 192) % 256); |
| 128 | (*packet_size_length) = 2; |
| 129 | } else { |
| 130 | rc = -EINVAL; |
| 131 | ecryptfs_printk(KERN_WARNING, |
| 132 | "Unsupported packet size: [%d]\n", size); |
| 133 | } |
| 134 | return rc; |
| 135 | } |
| 136 | |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 137 | static int |
| 138 | write_tag_64_packet(char *signature, struct ecryptfs_session_key *session_key, |
| 139 | char **packet, size_t *packet_len) |
| 140 | { |
| 141 | size_t i = 0; |
| 142 | size_t data_len; |
| 143 | size_t packet_size_len; |
| 144 | char *message; |
| 145 | int rc; |
| 146 | |
| 147 | /* |
| 148 | * ***** TAG 64 Packet Format ***** |
| 149 | * | Content Type | 1 byte | |
| 150 | * | Key Identifier Size | 1 or 2 bytes | |
| 151 | * | Key Identifier | arbitrary | |
| 152 | * | Encrypted File Encryption Key Size | 1 or 2 bytes | |
| 153 | * | Encrypted File Encryption Key | arbitrary | |
| 154 | */ |
| 155 | data_len = (5 + ECRYPTFS_SIG_SIZE_HEX |
| 156 | + session_key->encrypted_key_size); |
| 157 | *packet = kmalloc(data_len, GFP_KERNEL); |
| 158 | message = *packet; |
| 159 | if (!message) { |
| 160 | ecryptfs_printk(KERN_ERR, "Unable to allocate memory\n"); |
| 161 | rc = -ENOMEM; |
| 162 | goto out; |
| 163 | } |
| 164 | message[i++] = ECRYPTFS_TAG_64_PACKET_TYPE; |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 165 | rc = ecryptfs_write_packet_length(&message[i], ECRYPTFS_SIG_SIZE_HEX, |
| 166 | &packet_size_len); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 167 | if (rc) { |
| 168 | ecryptfs_printk(KERN_ERR, "Error generating tag 64 packet " |
| 169 | "header; cannot generate packet length\n"); |
| 170 | goto out; |
| 171 | } |
| 172 | i += packet_size_len; |
| 173 | memcpy(&message[i], signature, ECRYPTFS_SIG_SIZE_HEX); |
| 174 | i += ECRYPTFS_SIG_SIZE_HEX; |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 175 | rc = ecryptfs_write_packet_length(&message[i], |
| 176 | session_key->encrypted_key_size, |
| 177 | &packet_size_len); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 178 | if (rc) { |
| 179 | ecryptfs_printk(KERN_ERR, "Error generating tag 64 packet " |
| 180 | "header; cannot generate packet length\n"); |
| 181 | goto out; |
| 182 | } |
| 183 | i += packet_size_len; |
| 184 | memcpy(&message[i], session_key->encrypted_key, |
| 185 | session_key->encrypted_key_size); |
| 186 | i += session_key->encrypted_key_size; |
| 187 | *packet_len = i; |
| 188 | out: |
| 189 | return rc; |
| 190 | } |
| 191 | |
| 192 | static int |
Trevor Highland | 19e66a6 | 2008-02-06 01:38:36 -0800 | [diff] [blame] | 193 | parse_tag_65_packet(struct ecryptfs_session_key *session_key, u8 *cipher_code, |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 194 | struct ecryptfs_message *msg) |
| 195 | { |
| 196 | size_t i = 0; |
| 197 | char *data; |
| 198 | size_t data_len; |
| 199 | size_t m_size; |
| 200 | size_t message_len; |
| 201 | u16 checksum = 0; |
| 202 | u16 expected_checksum = 0; |
| 203 | int rc; |
| 204 | |
| 205 | /* |
| 206 | * ***** TAG 65 Packet Format ***** |
| 207 | * | Content Type | 1 byte | |
| 208 | * | Status Indicator | 1 byte | |
| 209 | * | File Encryption Key Size | 1 or 2 bytes | |
| 210 | * | File Encryption Key | arbitrary | |
| 211 | */ |
| 212 | message_len = msg->data_len; |
| 213 | data = msg->data; |
| 214 | if (message_len < 4) { |
| 215 | rc = -EIO; |
| 216 | goto out; |
| 217 | } |
| 218 | if (data[i++] != ECRYPTFS_TAG_65_PACKET_TYPE) { |
| 219 | ecryptfs_printk(KERN_ERR, "Type should be ECRYPTFS_TAG_65\n"); |
| 220 | rc = -EIO; |
| 221 | goto out; |
| 222 | } |
| 223 | if (data[i++]) { |
| 224 | ecryptfs_printk(KERN_ERR, "Status indicator has non-zero value " |
| 225 | "[%d]\n", data[i-1]); |
| 226 | rc = -EIO; |
| 227 | goto out; |
| 228 | } |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 229 | rc = ecryptfs_parse_packet_length(&data[i], &m_size, &data_len); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 230 | if (rc) { |
| 231 | ecryptfs_printk(KERN_WARNING, "Error parsing packet length; " |
| 232 | "rc = [%d]\n", rc); |
| 233 | goto out; |
| 234 | } |
| 235 | i += data_len; |
| 236 | if (message_len < (i + m_size)) { |
Tyler Hicks | 624ae52 | 2008-10-15 22:02:51 -0700 | [diff] [blame] | 237 | ecryptfs_printk(KERN_ERR, "The message received from ecryptfsd " |
| 238 | "is shorter than expected\n"); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 239 | rc = -EIO; |
| 240 | goto out; |
| 241 | } |
| 242 | if (m_size < 3) { |
| 243 | ecryptfs_printk(KERN_ERR, |
| 244 | "The decrypted key is not long enough to " |
| 245 | "include a cipher code and checksum\n"); |
| 246 | rc = -EIO; |
| 247 | goto out; |
| 248 | } |
| 249 | *cipher_code = data[i++]; |
| 250 | /* The decrypted key includes 1 byte cipher code and 2 byte checksum */ |
| 251 | session_key->decrypted_key_size = m_size - 3; |
| 252 | if (session_key->decrypted_key_size > ECRYPTFS_MAX_KEY_BYTES) { |
| 253 | ecryptfs_printk(KERN_ERR, "key_size [%d] larger than " |
| 254 | "the maximum key size [%d]\n", |
| 255 | session_key->decrypted_key_size, |
| 256 | ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES); |
| 257 | rc = -EIO; |
| 258 | goto out; |
| 259 | } |
| 260 | memcpy(session_key->decrypted_key, &data[i], |
| 261 | session_key->decrypted_key_size); |
| 262 | i += session_key->decrypted_key_size; |
| 263 | expected_checksum += (unsigned char)(data[i++]) << 8; |
| 264 | expected_checksum += (unsigned char)(data[i++]); |
| 265 | for (i = 0; i < session_key->decrypted_key_size; i++) |
| 266 | checksum += session_key->decrypted_key[i]; |
| 267 | if (expected_checksum != checksum) { |
| 268 | ecryptfs_printk(KERN_ERR, "Invalid checksum for file " |
| 269 | "encryption key; expected [%x]; calculated " |
| 270 | "[%x]\n", expected_checksum, checksum); |
| 271 | rc = -EIO; |
| 272 | } |
| 273 | out: |
| 274 | return rc; |
| 275 | } |
| 276 | |
| 277 | |
| 278 | static int |
Trevor Highland | 19e66a6 | 2008-02-06 01:38:36 -0800 | [diff] [blame] | 279 | write_tag_66_packet(char *signature, u8 cipher_code, |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 280 | struct ecryptfs_crypt_stat *crypt_stat, char **packet, |
| 281 | size_t *packet_len) |
| 282 | { |
| 283 | size_t i = 0; |
| 284 | size_t j; |
| 285 | size_t data_len; |
| 286 | size_t checksum = 0; |
| 287 | size_t packet_size_len; |
| 288 | char *message; |
| 289 | int rc; |
| 290 | |
| 291 | /* |
| 292 | * ***** TAG 66 Packet Format ***** |
| 293 | * | Content Type | 1 byte | |
| 294 | * | Key Identifier Size | 1 or 2 bytes | |
| 295 | * | Key Identifier | arbitrary | |
| 296 | * | File Encryption Key Size | 1 or 2 bytes | |
| 297 | * | File Encryption Key | arbitrary | |
| 298 | */ |
| 299 | data_len = (5 + ECRYPTFS_SIG_SIZE_HEX + crypt_stat->key_size); |
| 300 | *packet = kmalloc(data_len, GFP_KERNEL); |
| 301 | message = *packet; |
| 302 | if (!message) { |
| 303 | ecryptfs_printk(KERN_ERR, "Unable to allocate memory\n"); |
| 304 | rc = -ENOMEM; |
| 305 | goto out; |
| 306 | } |
| 307 | message[i++] = ECRYPTFS_TAG_66_PACKET_TYPE; |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 308 | rc = ecryptfs_write_packet_length(&message[i], ECRYPTFS_SIG_SIZE_HEX, |
| 309 | &packet_size_len); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 310 | if (rc) { |
| 311 | ecryptfs_printk(KERN_ERR, "Error generating tag 66 packet " |
| 312 | "header; cannot generate packet length\n"); |
| 313 | goto out; |
| 314 | } |
| 315 | i += packet_size_len; |
| 316 | memcpy(&message[i], signature, ECRYPTFS_SIG_SIZE_HEX); |
| 317 | i += ECRYPTFS_SIG_SIZE_HEX; |
| 318 | /* The encrypted key includes 1 byte cipher code and 2 byte checksum */ |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 319 | rc = ecryptfs_write_packet_length(&message[i], crypt_stat->key_size + 3, |
| 320 | &packet_size_len); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 321 | if (rc) { |
| 322 | ecryptfs_printk(KERN_ERR, "Error generating tag 66 packet " |
| 323 | "header; cannot generate packet length\n"); |
| 324 | goto out; |
| 325 | } |
| 326 | i += packet_size_len; |
| 327 | message[i++] = cipher_code; |
| 328 | memcpy(&message[i], crypt_stat->key, crypt_stat->key_size); |
| 329 | i += crypt_stat->key_size; |
| 330 | for (j = 0; j < crypt_stat->key_size; j++) |
| 331 | checksum += crypt_stat->key[j]; |
| 332 | message[i++] = (checksum / 256) % 256; |
| 333 | message[i++] = (checksum % 256); |
| 334 | *packet_len = i; |
| 335 | out: |
| 336 | return rc; |
| 337 | } |
| 338 | |
| 339 | static int |
| 340 | parse_tag_67_packet(struct ecryptfs_key_record *key_rec, |
| 341 | struct ecryptfs_message *msg) |
| 342 | { |
| 343 | size_t i = 0; |
| 344 | char *data; |
| 345 | size_t data_len; |
| 346 | size_t message_len; |
| 347 | int rc; |
| 348 | |
| 349 | /* |
| 350 | * ***** TAG 65 Packet Format ***** |
| 351 | * | Content Type | 1 byte | |
| 352 | * | Status Indicator | 1 byte | |
| 353 | * | Encrypted File Encryption Key Size | 1 or 2 bytes | |
| 354 | * | Encrypted File Encryption Key | arbitrary | |
| 355 | */ |
| 356 | message_len = msg->data_len; |
| 357 | data = msg->data; |
| 358 | /* verify that everything through the encrypted FEK size is present */ |
| 359 | if (message_len < 4) { |
| 360 | rc = -EIO; |
Michael Halcrow | df261c5 | 2009-01-06 14:42:02 -0800 | [diff] [blame] | 361 | printk(KERN_ERR "%s: message_len is [%zd]; minimum acceptable " |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 362 | "message length is [%d]\n", __func__, message_len, 4); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 363 | goto out; |
| 364 | } |
| 365 | if (data[i++] != ECRYPTFS_TAG_67_PACKET_TYPE) { |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 366 | rc = -EIO; |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 367 | printk(KERN_ERR "%s: Type should be ECRYPTFS_TAG_67\n", |
| 368 | __func__); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 369 | goto out; |
| 370 | } |
| 371 | if (data[i++]) { |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 372 | rc = -EIO; |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 373 | printk(KERN_ERR "%s: Status indicator has non zero " |
| 374 | "value [%d]\n", __func__, data[i-1]); |
| 375 | |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 376 | goto out; |
| 377 | } |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 378 | rc = ecryptfs_parse_packet_length(&data[i], &key_rec->enc_key_size, |
| 379 | &data_len); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 380 | if (rc) { |
| 381 | ecryptfs_printk(KERN_WARNING, "Error parsing packet length; " |
| 382 | "rc = [%d]\n", rc); |
| 383 | goto out; |
| 384 | } |
| 385 | i += data_len; |
| 386 | if (message_len < (i + key_rec->enc_key_size)) { |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 387 | rc = -EIO; |
Michael Halcrow | df261c5 | 2009-01-06 14:42:02 -0800 | [diff] [blame] | 388 | printk(KERN_ERR "%s: message_len [%zd]; max len is [%zd]\n", |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 389 | __func__, message_len, (i + key_rec->enc_key_size)); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 390 | goto out; |
| 391 | } |
| 392 | if (key_rec->enc_key_size > ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES) { |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 393 | rc = -EIO; |
Michael Halcrow | df261c5 | 2009-01-06 14:42:02 -0800 | [diff] [blame] | 394 | printk(KERN_ERR "%s: Encrypted key_size [%zd] larger than " |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 395 | "the maximum key size [%d]\n", __func__, |
| 396 | key_rec->enc_key_size, |
| 397 | ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 398 | goto out; |
| 399 | } |
| 400 | memcpy(key_rec->enc_key, &data[i], key_rec->enc_key_size); |
| 401 | out: |
| 402 | return rc; |
| 403 | } |
| 404 | |
Michael Halcrow | cd9d67d | 2007-10-16 01:28:04 -0700 | [diff] [blame] | 405 | static int |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 406 | ecryptfs_find_global_auth_tok_for_sig( |
| 407 | struct ecryptfs_global_auth_tok **global_auth_tok, |
| 408 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat, char *sig) |
| 409 | { |
| 410 | struct ecryptfs_global_auth_tok *walker; |
| 411 | int rc = 0; |
| 412 | |
| 413 | (*global_auth_tok) = NULL; |
| 414 | mutex_lock(&mount_crypt_stat->global_auth_tok_list_mutex); |
| 415 | list_for_each_entry(walker, |
| 416 | &mount_crypt_stat->global_auth_tok_list, |
| 417 | mount_crypt_stat_list) { |
| 418 | if (memcmp(walker->sig, sig, ECRYPTFS_SIG_SIZE_HEX) == 0) { |
| 419 | (*global_auth_tok) = walker; |
| 420 | goto out; |
| 421 | } |
| 422 | } |
| 423 | rc = -EINVAL; |
| 424 | out: |
| 425 | mutex_unlock(&mount_crypt_stat->global_auth_tok_list_mutex); |
| 426 | return rc; |
| 427 | } |
| 428 | |
| 429 | /** |
| 430 | * ecryptfs_find_auth_tok_for_sig |
| 431 | * @auth_tok: Set to the matching auth_tok; NULL if not found |
| 432 | * @crypt_stat: inode crypt_stat crypto context |
| 433 | * @sig: Sig of auth_tok to find |
| 434 | * |
| 435 | * For now, this function simply looks at the registered auth_tok's |
| 436 | * linked off the mount_crypt_stat, so all the auth_toks that can be |
| 437 | * used must be registered at mount time. This function could |
| 438 | * potentially try a lot harder to find auth_tok's (e.g., by calling |
| 439 | * out to ecryptfsd to dynamically retrieve an auth_tok object) so |
| 440 | * that static registration of auth_tok's will no longer be necessary. |
| 441 | * |
| 442 | * Returns zero on no error; non-zero on error |
| 443 | */ |
| 444 | static int |
| 445 | ecryptfs_find_auth_tok_for_sig( |
| 446 | struct ecryptfs_auth_tok **auth_tok, |
| 447 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat, |
| 448 | char *sig) |
| 449 | { |
| 450 | struct ecryptfs_global_auth_tok *global_auth_tok; |
| 451 | int rc = 0; |
| 452 | |
| 453 | (*auth_tok) = NULL; |
| 454 | if (ecryptfs_find_global_auth_tok_for_sig(&global_auth_tok, |
| 455 | mount_crypt_stat, sig)) { |
| 456 | struct key *auth_tok_key; |
| 457 | |
| 458 | rc = ecryptfs_keyring_auth_tok_for_sig(&auth_tok_key, auth_tok, |
| 459 | sig); |
| 460 | } else |
| 461 | (*auth_tok) = global_auth_tok->global_auth_tok; |
| 462 | return rc; |
| 463 | } |
| 464 | |
| 465 | /** |
| 466 | * write_tag_70_packet can gobble a lot of stack space. We stuff most |
| 467 | * of the function's parameters in a kmalloc'd struct to help reduce |
| 468 | * eCryptfs' overall stack usage. |
| 469 | */ |
| 470 | struct ecryptfs_write_tag_70_packet_silly_stack { |
| 471 | u8 cipher_code; |
| 472 | size_t max_packet_size; |
| 473 | size_t packet_size_len; |
| 474 | size_t block_aligned_filename_size; |
| 475 | size_t block_size; |
| 476 | size_t i; |
| 477 | size_t j; |
| 478 | size_t num_rand_bytes; |
| 479 | struct mutex *tfm_mutex; |
| 480 | char *block_aligned_filename; |
| 481 | struct ecryptfs_auth_tok *auth_tok; |
| 482 | struct scatterlist src_sg; |
| 483 | struct scatterlist dst_sg; |
| 484 | struct blkcipher_desc desc; |
| 485 | char iv[ECRYPTFS_MAX_IV_BYTES]; |
| 486 | char hash[ECRYPTFS_TAG_70_DIGEST_SIZE]; |
| 487 | char tmp_hash[ECRYPTFS_TAG_70_DIGEST_SIZE]; |
| 488 | struct hash_desc hash_desc; |
| 489 | struct scatterlist hash_sg; |
| 490 | }; |
| 491 | |
| 492 | /** |
| 493 | * write_tag_70_packet - Write encrypted filename (EFN) packet against FNEK |
| 494 | * @filename: NULL-terminated filename string |
| 495 | * |
| 496 | * This is the simplest mechanism for achieving filename encryption in |
| 497 | * eCryptfs. It encrypts the given filename with the mount-wide |
| 498 | * filename encryption key (FNEK) and stores it in a packet to @dest, |
| 499 | * which the callee will encode and write directly into the dentry |
| 500 | * name. |
| 501 | */ |
| 502 | int |
| 503 | ecryptfs_write_tag_70_packet(char *dest, size_t *remaining_bytes, |
| 504 | size_t *packet_size, |
| 505 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat, |
| 506 | char *filename, size_t filename_size) |
| 507 | { |
| 508 | struct ecryptfs_write_tag_70_packet_silly_stack *s; |
| 509 | int rc = 0; |
| 510 | |
| 511 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
| 512 | if (!s) { |
| 513 | printk(KERN_ERR "%s: Out of memory whilst trying to kmalloc " |
Michael Halcrow | df261c5 | 2009-01-06 14:42:02 -0800 | [diff] [blame] | 514 | "[%zd] bytes of kernel memory\n", __func__, sizeof(*s)); |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 515 | goto out; |
| 516 | } |
| 517 | s->desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP; |
| 518 | (*packet_size) = 0; |
| 519 | rc = ecryptfs_get_tfm_and_mutex_for_cipher_name( |
| 520 | &s->desc.tfm, |
| 521 | &s->tfm_mutex, mount_crypt_stat->global_default_fn_cipher_name); |
| 522 | if (unlikely(rc)) { |
| 523 | printk(KERN_ERR "Internal error whilst attempting to get " |
| 524 | "tfm and mutex for cipher name [%s]; rc = [%d]\n", |
| 525 | mount_crypt_stat->global_default_fn_cipher_name, rc); |
| 526 | goto out; |
| 527 | } |
| 528 | mutex_lock(s->tfm_mutex); |
| 529 | s->block_size = crypto_blkcipher_blocksize(s->desc.tfm); |
| 530 | /* Plus one for the \0 separator between the random prefix |
| 531 | * and the plaintext filename */ |
| 532 | s->num_rand_bytes = (ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES + 1); |
| 533 | s->block_aligned_filename_size = (s->num_rand_bytes + filename_size); |
| 534 | if ((s->block_aligned_filename_size % s->block_size) != 0) { |
| 535 | s->num_rand_bytes += (s->block_size |
| 536 | - (s->block_aligned_filename_size |
| 537 | % s->block_size)); |
| 538 | s->block_aligned_filename_size = (s->num_rand_bytes |
| 539 | + filename_size); |
| 540 | } |
| 541 | /* Octet 0: Tag 70 identifier |
| 542 | * Octets 1-N1: Tag 70 packet size (includes cipher identifier |
| 543 | * and block-aligned encrypted filename size) |
| 544 | * Octets N1-N2: FNEK sig (ECRYPTFS_SIG_SIZE) |
| 545 | * Octet N2-N3: Cipher identifier (1 octet) |
| 546 | * Octets N3-N4: Block-aligned encrypted filename |
| 547 | * - Consists of a minimum number of random characters, a \0 |
| 548 | * separator, and then the filename */ |
| 549 | s->max_packet_size = (1 /* Tag 70 identifier */ |
| 550 | + 3 /* Max Tag 70 packet size */ |
| 551 | + ECRYPTFS_SIG_SIZE /* FNEK sig */ |
| 552 | + 1 /* Cipher identifier */ |
| 553 | + s->block_aligned_filename_size); |
| 554 | if (dest == NULL) { |
| 555 | (*packet_size) = s->max_packet_size; |
| 556 | goto out_unlock; |
| 557 | } |
| 558 | if (s->max_packet_size > (*remaining_bytes)) { |
Michael Halcrow | a8f1286 | 2009-01-06 14:42:03 -0800 | [diff] [blame] | 559 | printk(KERN_WARNING "%s: Require [%zd] bytes to write; only " |
| 560 | "[%zd] available\n", __func__, s->max_packet_size, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 561 | (*remaining_bytes)); |
| 562 | rc = -EINVAL; |
| 563 | goto out_unlock; |
| 564 | } |
| 565 | s->block_aligned_filename = kzalloc(s->block_aligned_filename_size, |
| 566 | GFP_KERNEL); |
| 567 | if (!s->block_aligned_filename) { |
| 568 | printk(KERN_ERR "%s: Out of kernel memory whilst attempting to " |
Michael Halcrow | df261c5 | 2009-01-06 14:42:02 -0800 | [diff] [blame] | 569 | "kzalloc [%zd] bytes\n", __func__, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 570 | s->block_aligned_filename_size); |
| 571 | rc = -ENOMEM; |
| 572 | goto out_unlock; |
| 573 | } |
| 574 | s->i = 0; |
| 575 | dest[s->i++] = ECRYPTFS_TAG_70_PACKET_TYPE; |
| 576 | rc = ecryptfs_write_packet_length(&dest[s->i], |
| 577 | (ECRYPTFS_SIG_SIZE |
| 578 | + 1 /* Cipher code */ |
| 579 | + s->block_aligned_filename_size), |
| 580 | &s->packet_size_len); |
| 581 | if (rc) { |
| 582 | printk(KERN_ERR "%s: Error generating tag 70 packet " |
| 583 | "header; cannot generate packet length; rc = [%d]\n", |
| 584 | __func__, rc); |
| 585 | goto out_free_unlock; |
| 586 | } |
| 587 | s->i += s->packet_size_len; |
| 588 | ecryptfs_from_hex(&dest[s->i], |
| 589 | mount_crypt_stat->global_default_fnek_sig, |
| 590 | ECRYPTFS_SIG_SIZE); |
| 591 | s->i += ECRYPTFS_SIG_SIZE; |
| 592 | s->cipher_code = ecryptfs_code_for_cipher_string( |
| 593 | mount_crypt_stat->global_default_fn_cipher_name, |
| 594 | mount_crypt_stat->global_default_fn_cipher_key_bytes); |
| 595 | if (s->cipher_code == 0) { |
| 596 | printk(KERN_WARNING "%s: Unable to generate code for " |
Michael Halcrow | a8f1286 | 2009-01-06 14:42:03 -0800 | [diff] [blame] | 597 | "cipher [%s] with key bytes [%zd]\n", __func__, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 598 | mount_crypt_stat->global_default_fn_cipher_name, |
| 599 | mount_crypt_stat->global_default_fn_cipher_key_bytes); |
| 600 | rc = -EINVAL; |
| 601 | goto out_free_unlock; |
| 602 | } |
| 603 | dest[s->i++] = s->cipher_code; |
| 604 | rc = ecryptfs_find_auth_tok_for_sig( |
| 605 | &s->auth_tok, mount_crypt_stat, |
| 606 | mount_crypt_stat->global_default_fnek_sig); |
| 607 | if (rc) { |
| 608 | printk(KERN_ERR "%s: Error attempting to find auth tok for " |
| 609 | "fnek sig [%s]; rc = [%d]\n", __func__, |
| 610 | mount_crypt_stat->global_default_fnek_sig, rc); |
| 611 | goto out_free_unlock; |
| 612 | } |
| 613 | /* TODO: Support other key modules than passphrase for |
| 614 | * filename encryption */ |
| 615 | BUG_ON(s->auth_tok->token_type != ECRYPTFS_PASSWORD); |
| 616 | sg_init_one( |
| 617 | &s->hash_sg, |
| 618 | (u8 *)s->auth_tok->token.password.session_key_encryption_key, |
| 619 | s->auth_tok->token.password.session_key_encryption_key_bytes); |
| 620 | s->hash_desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP; |
| 621 | s->hash_desc.tfm = crypto_alloc_hash(ECRYPTFS_TAG_70_DIGEST, 0, |
| 622 | CRYPTO_ALG_ASYNC); |
| 623 | if (IS_ERR(s->hash_desc.tfm)) { |
| 624 | rc = PTR_ERR(s->hash_desc.tfm); |
| 625 | printk(KERN_ERR "%s: Error attempting to " |
| 626 | "allocate hash crypto context; rc = [%d]\n", |
| 627 | __func__, rc); |
| 628 | goto out_free_unlock; |
| 629 | } |
| 630 | rc = crypto_hash_init(&s->hash_desc); |
| 631 | if (rc) { |
| 632 | printk(KERN_ERR |
| 633 | "%s: Error initializing crypto hash; rc = [%d]\n", |
| 634 | __func__, rc); |
| 635 | goto out_release_free_unlock; |
| 636 | } |
| 637 | rc = crypto_hash_update( |
| 638 | &s->hash_desc, &s->hash_sg, |
| 639 | s->auth_tok->token.password.session_key_encryption_key_bytes); |
| 640 | if (rc) { |
| 641 | printk(KERN_ERR |
| 642 | "%s: Error updating crypto hash; rc = [%d]\n", |
| 643 | __func__, rc); |
| 644 | goto out_release_free_unlock; |
| 645 | } |
| 646 | rc = crypto_hash_final(&s->hash_desc, s->hash); |
| 647 | if (rc) { |
| 648 | printk(KERN_ERR |
| 649 | "%s: Error finalizing crypto hash; rc = [%d]\n", |
| 650 | __func__, rc); |
| 651 | goto out_release_free_unlock; |
| 652 | } |
| 653 | for (s->j = 0; s->j < (s->num_rand_bytes - 1); s->j++) { |
| 654 | s->block_aligned_filename[s->j] = |
| 655 | s->hash[(s->j % ECRYPTFS_TAG_70_DIGEST_SIZE)]; |
| 656 | if ((s->j % ECRYPTFS_TAG_70_DIGEST_SIZE) |
| 657 | == (ECRYPTFS_TAG_70_DIGEST_SIZE - 1)) { |
| 658 | sg_init_one(&s->hash_sg, (u8 *)s->hash, |
| 659 | ECRYPTFS_TAG_70_DIGEST_SIZE); |
| 660 | rc = crypto_hash_init(&s->hash_desc); |
| 661 | if (rc) { |
| 662 | printk(KERN_ERR |
| 663 | "%s: Error initializing crypto hash; " |
| 664 | "rc = [%d]\n", __func__, rc); |
| 665 | goto out_release_free_unlock; |
| 666 | } |
| 667 | rc = crypto_hash_update(&s->hash_desc, &s->hash_sg, |
| 668 | ECRYPTFS_TAG_70_DIGEST_SIZE); |
| 669 | if (rc) { |
| 670 | printk(KERN_ERR |
| 671 | "%s: Error updating crypto hash; " |
| 672 | "rc = [%d]\n", __func__, rc); |
| 673 | goto out_release_free_unlock; |
| 674 | } |
| 675 | rc = crypto_hash_final(&s->hash_desc, s->tmp_hash); |
| 676 | if (rc) { |
| 677 | printk(KERN_ERR |
| 678 | "%s: Error finalizing crypto hash; " |
| 679 | "rc = [%d]\n", __func__, rc); |
| 680 | goto out_release_free_unlock; |
| 681 | } |
| 682 | memcpy(s->hash, s->tmp_hash, |
| 683 | ECRYPTFS_TAG_70_DIGEST_SIZE); |
| 684 | } |
| 685 | if (s->block_aligned_filename[s->j] == '\0') |
| 686 | s->block_aligned_filename[s->j] = ECRYPTFS_NON_NULL; |
| 687 | } |
| 688 | memcpy(&s->block_aligned_filename[s->num_rand_bytes], filename, |
| 689 | filename_size); |
| 690 | rc = virt_to_scatterlist(s->block_aligned_filename, |
| 691 | s->block_aligned_filename_size, &s->src_sg, 1); |
| 692 | if (rc != 1) { |
| 693 | printk(KERN_ERR "%s: Internal error whilst attempting to " |
| 694 | "convert filename memory to scatterlist; " |
| 695 | "expected rc = 1; got rc = [%d]. " |
Michael Halcrow | a8f1286 | 2009-01-06 14:42:03 -0800 | [diff] [blame] | 696 | "block_aligned_filename_size = [%zd]\n", __func__, rc, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 697 | s->block_aligned_filename_size); |
| 698 | goto out_release_free_unlock; |
| 699 | } |
| 700 | rc = virt_to_scatterlist(&dest[s->i], s->block_aligned_filename_size, |
| 701 | &s->dst_sg, 1); |
| 702 | if (rc != 1) { |
| 703 | printk(KERN_ERR "%s: Internal error whilst attempting to " |
| 704 | "convert encrypted filename memory to scatterlist; " |
| 705 | "expected rc = 1; got rc = [%d]. " |
Michael Halcrow | a8f1286 | 2009-01-06 14:42:03 -0800 | [diff] [blame] | 706 | "block_aligned_filename_size = [%zd]\n", __func__, rc, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 707 | s->block_aligned_filename_size); |
| 708 | goto out_release_free_unlock; |
| 709 | } |
| 710 | /* The characters in the first block effectively do the job |
| 711 | * of the IV here, so we just use 0's for the IV. Note the |
| 712 | * constraint that ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES |
| 713 | * >= ECRYPTFS_MAX_IV_BYTES. */ |
| 714 | memset(s->iv, 0, ECRYPTFS_MAX_IV_BYTES); |
| 715 | s->desc.info = s->iv; |
| 716 | rc = crypto_blkcipher_setkey( |
| 717 | s->desc.tfm, |
| 718 | s->auth_tok->token.password.session_key_encryption_key, |
| 719 | mount_crypt_stat->global_default_fn_cipher_key_bytes); |
| 720 | if (rc < 0) { |
| 721 | printk(KERN_ERR "%s: Error setting key for crypto context; " |
| 722 | "rc = [%d]. s->auth_tok->token.password.session_key_" |
| 723 | "encryption_key = [0x%p]; mount_crypt_stat->" |
Michael Halcrow | df261c5 | 2009-01-06 14:42:02 -0800 | [diff] [blame] | 724 | "global_default_fn_cipher_key_bytes = [%zd]\n", __func__, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 725 | rc, |
| 726 | s->auth_tok->token.password.session_key_encryption_key, |
| 727 | mount_crypt_stat->global_default_fn_cipher_key_bytes); |
| 728 | goto out_release_free_unlock; |
| 729 | } |
| 730 | rc = crypto_blkcipher_encrypt_iv(&s->desc, &s->dst_sg, &s->src_sg, |
| 731 | s->block_aligned_filename_size); |
| 732 | if (rc) { |
| 733 | printk(KERN_ERR "%s: Error attempting to encrypt filename; " |
| 734 | "rc = [%d]\n", __func__, rc); |
| 735 | goto out_release_free_unlock; |
| 736 | } |
| 737 | s->i += s->block_aligned_filename_size; |
| 738 | (*packet_size) = s->i; |
| 739 | (*remaining_bytes) -= (*packet_size); |
| 740 | out_release_free_unlock: |
| 741 | crypto_free_hash(s->hash_desc.tfm); |
| 742 | out_free_unlock: |
Johannes Weiner | 00fcf2c | 2009-03-31 15:24:42 -0700 | [diff] [blame] | 743 | kzfree(s->block_aligned_filename); |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 744 | out_unlock: |
| 745 | mutex_unlock(s->tfm_mutex); |
| 746 | out: |
| 747 | kfree(s); |
| 748 | return rc; |
| 749 | } |
| 750 | |
| 751 | struct ecryptfs_parse_tag_70_packet_silly_stack { |
| 752 | u8 cipher_code; |
| 753 | size_t max_packet_size; |
| 754 | size_t packet_size_len; |
| 755 | size_t parsed_tag_70_packet_size; |
| 756 | size_t block_aligned_filename_size; |
| 757 | size_t block_size; |
| 758 | size_t i; |
| 759 | struct mutex *tfm_mutex; |
| 760 | char *decrypted_filename; |
| 761 | struct ecryptfs_auth_tok *auth_tok; |
| 762 | struct scatterlist src_sg; |
| 763 | struct scatterlist dst_sg; |
| 764 | struct blkcipher_desc desc; |
| 765 | char fnek_sig_hex[ECRYPTFS_SIG_SIZE_HEX + 1]; |
| 766 | char iv[ECRYPTFS_MAX_IV_BYTES]; |
| 767 | char cipher_string[ECRYPTFS_MAX_CIPHER_NAME_SIZE]; |
| 768 | }; |
| 769 | |
| 770 | /** |
| 771 | * parse_tag_70_packet - Parse and process FNEK-encrypted passphrase packet |
| 772 | * @filename: This function kmalloc's the memory for the filename |
Michael Halcrow | 7d8bc2b | 2009-01-06 14:42:04 -0800 | [diff] [blame] | 773 | * @filename_size: This function sets this to the amount of memory |
| 774 | * kmalloc'd for the filename |
| 775 | * @packet_size: This function sets this to the the number of octets |
| 776 | * in the packet parsed |
| 777 | * @mount_crypt_stat: The mount-wide cryptographic context |
| 778 | * @data: The memory location containing the start of the tag 70 |
| 779 | * packet |
| 780 | * @max_packet_size: The maximum legal size of the packet to be parsed |
| 781 | * from @data |
| 782 | * |
| 783 | * Returns zero on success; non-zero otherwise |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 784 | */ |
| 785 | int |
| 786 | ecryptfs_parse_tag_70_packet(char **filename, size_t *filename_size, |
| 787 | size_t *packet_size, |
| 788 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat, |
| 789 | char *data, size_t max_packet_size) |
| 790 | { |
| 791 | struct ecryptfs_parse_tag_70_packet_silly_stack *s; |
| 792 | int rc = 0; |
| 793 | |
| 794 | (*packet_size) = 0; |
| 795 | (*filename_size) = 0; |
| 796 | (*filename) = NULL; |
| 797 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
| 798 | if (!s) { |
| 799 | printk(KERN_ERR "%s: Out of memory whilst trying to kmalloc " |
Michael Halcrow | a8f1286 | 2009-01-06 14:42:03 -0800 | [diff] [blame] | 800 | "[%zd] bytes of kernel memory\n", __func__, sizeof(*s)); |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 801 | goto out; |
| 802 | } |
| 803 | s->desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP; |
| 804 | if (max_packet_size < (1 + 1 + ECRYPTFS_SIG_SIZE + 1 + 1)) { |
Michael Halcrow | df261c5 | 2009-01-06 14:42:02 -0800 | [diff] [blame] | 805 | printk(KERN_WARNING "%s: max_packet_size is [%zd]; it must be " |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 806 | "at least [%d]\n", __func__, max_packet_size, |
| 807 | (1 + 1 + ECRYPTFS_SIG_SIZE + 1 + 1)); |
| 808 | rc = -EINVAL; |
| 809 | goto out; |
| 810 | } |
| 811 | /* Octet 0: Tag 70 identifier |
| 812 | * Octets 1-N1: Tag 70 packet size (includes cipher identifier |
| 813 | * and block-aligned encrypted filename size) |
| 814 | * Octets N1-N2: FNEK sig (ECRYPTFS_SIG_SIZE) |
| 815 | * Octet N2-N3: Cipher identifier (1 octet) |
| 816 | * Octets N3-N4: Block-aligned encrypted filename |
| 817 | * - Consists of a minimum number of random numbers, a \0 |
| 818 | * separator, and then the filename */ |
| 819 | if (data[(*packet_size)++] != ECRYPTFS_TAG_70_PACKET_TYPE) { |
| 820 | printk(KERN_WARNING "%s: Invalid packet tag [0x%.2x]; must be " |
| 821 | "tag [0x%.2x]\n", __func__, |
| 822 | data[((*packet_size) - 1)], ECRYPTFS_TAG_70_PACKET_TYPE); |
| 823 | rc = -EINVAL; |
| 824 | goto out; |
| 825 | } |
| 826 | rc = ecryptfs_parse_packet_length(&data[(*packet_size)], |
| 827 | &s->parsed_tag_70_packet_size, |
| 828 | &s->packet_size_len); |
| 829 | if (rc) { |
| 830 | printk(KERN_WARNING "%s: Error parsing packet length; " |
| 831 | "rc = [%d]\n", __func__, rc); |
| 832 | goto out; |
| 833 | } |
| 834 | s->block_aligned_filename_size = (s->parsed_tag_70_packet_size |
| 835 | - ECRYPTFS_SIG_SIZE - 1); |
| 836 | if ((1 + s->packet_size_len + s->parsed_tag_70_packet_size) |
| 837 | > max_packet_size) { |
Michael Halcrow | a8f1286 | 2009-01-06 14:42:03 -0800 | [diff] [blame] | 838 | printk(KERN_WARNING "%s: max_packet_size is [%zd]; real packet " |
| 839 | "size is [%zd]\n", __func__, max_packet_size, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 840 | (1 + s->packet_size_len + 1 |
| 841 | + s->block_aligned_filename_size)); |
| 842 | rc = -EINVAL; |
| 843 | goto out; |
| 844 | } |
| 845 | (*packet_size) += s->packet_size_len; |
| 846 | ecryptfs_to_hex(s->fnek_sig_hex, &data[(*packet_size)], |
| 847 | ECRYPTFS_SIG_SIZE); |
| 848 | s->fnek_sig_hex[ECRYPTFS_SIG_SIZE_HEX] = '\0'; |
| 849 | (*packet_size) += ECRYPTFS_SIG_SIZE; |
| 850 | s->cipher_code = data[(*packet_size)++]; |
| 851 | rc = ecryptfs_cipher_code_to_string(s->cipher_string, s->cipher_code); |
| 852 | if (rc) { |
| 853 | printk(KERN_WARNING "%s: Cipher code [%d] is invalid\n", |
| 854 | __func__, s->cipher_code); |
| 855 | goto out; |
| 856 | } |
| 857 | rc = ecryptfs_get_tfm_and_mutex_for_cipher_name(&s->desc.tfm, |
| 858 | &s->tfm_mutex, |
| 859 | s->cipher_string); |
| 860 | if (unlikely(rc)) { |
| 861 | printk(KERN_ERR "Internal error whilst attempting to get " |
| 862 | "tfm and mutex for cipher name [%s]; rc = [%d]\n", |
| 863 | s->cipher_string, rc); |
| 864 | goto out; |
| 865 | } |
| 866 | mutex_lock(s->tfm_mutex); |
| 867 | rc = virt_to_scatterlist(&data[(*packet_size)], |
| 868 | s->block_aligned_filename_size, &s->src_sg, 1); |
| 869 | if (rc != 1) { |
| 870 | printk(KERN_ERR "%s: Internal error whilst attempting to " |
| 871 | "convert encrypted filename memory to scatterlist; " |
| 872 | "expected rc = 1; got rc = [%d]. " |
Michael Halcrow | a8f1286 | 2009-01-06 14:42:03 -0800 | [diff] [blame] | 873 | "block_aligned_filename_size = [%zd]\n", __func__, rc, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 874 | s->block_aligned_filename_size); |
| 875 | goto out_unlock; |
| 876 | } |
| 877 | (*packet_size) += s->block_aligned_filename_size; |
| 878 | s->decrypted_filename = kmalloc(s->block_aligned_filename_size, |
| 879 | GFP_KERNEL); |
| 880 | if (!s->decrypted_filename) { |
| 881 | printk(KERN_ERR "%s: Out of memory whilst attempting to " |
Michael Halcrow | a8f1286 | 2009-01-06 14:42:03 -0800 | [diff] [blame] | 882 | "kmalloc [%zd] bytes\n", __func__, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 883 | s->block_aligned_filename_size); |
| 884 | rc = -ENOMEM; |
| 885 | goto out_unlock; |
| 886 | } |
| 887 | rc = virt_to_scatterlist(s->decrypted_filename, |
| 888 | s->block_aligned_filename_size, &s->dst_sg, 1); |
| 889 | if (rc != 1) { |
| 890 | printk(KERN_ERR "%s: Internal error whilst attempting to " |
| 891 | "convert decrypted filename memory to scatterlist; " |
| 892 | "expected rc = 1; got rc = [%d]. " |
Michael Halcrow | a8f1286 | 2009-01-06 14:42:03 -0800 | [diff] [blame] | 893 | "block_aligned_filename_size = [%zd]\n", __func__, rc, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 894 | s->block_aligned_filename_size); |
| 895 | goto out_free_unlock; |
| 896 | } |
| 897 | /* The characters in the first block effectively do the job of |
| 898 | * the IV here, so we just use 0's for the IV. Note the |
| 899 | * constraint that ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES |
| 900 | * >= ECRYPTFS_MAX_IV_BYTES. */ |
| 901 | memset(s->iv, 0, ECRYPTFS_MAX_IV_BYTES); |
| 902 | s->desc.info = s->iv; |
| 903 | rc = ecryptfs_find_auth_tok_for_sig(&s->auth_tok, mount_crypt_stat, |
| 904 | s->fnek_sig_hex); |
| 905 | if (rc) { |
| 906 | printk(KERN_ERR "%s: Error attempting to find auth tok for " |
| 907 | "fnek sig [%s]; rc = [%d]\n", __func__, s->fnek_sig_hex, |
| 908 | rc); |
| 909 | goto out_free_unlock; |
| 910 | } |
| 911 | /* TODO: Support other key modules than passphrase for |
| 912 | * filename encryption */ |
| 913 | BUG_ON(s->auth_tok->token_type != ECRYPTFS_PASSWORD); |
| 914 | rc = crypto_blkcipher_setkey( |
| 915 | s->desc.tfm, |
| 916 | s->auth_tok->token.password.session_key_encryption_key, |
| 917 | mount_crypt_stat->global_default_fn_cipher_key_bytes); |
| 918 | if (rc < 0) { |
| 919 | printk(KERN_ERR "%s: Error setting key for crypto context; " |
| 920 | "rc = [%d]. s->auth_tok->token.password.session_key_" |
| 921 | "encryption_key = [0x%p]; mount_crypt_stat->" |
Michael Halcrow | df261c5 | 2009-01-06 14:42:02 -0800 | [diff] [blame] | 922 | "global_default_fn_cipher_key_bytes = [%zd]\n", __func__, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 923 | rc, |
| 924 | s->auth_tok->token.password.session_key_encryption_key, |
| 925 | mount_crypt_stat->global_default_fn_cipher_key_bytes); |
| 926 | goto out_free_unlock; |
| 927 | } |
| 928 | rc = crypto_blkcipher_decrypt_iv(&s->desc, &s->dst_sg, &s->src_sg, |
| 929 | s->block_aligned_filename_size); |
| 930 | if (rc) { |
| 931 | printk(KERN_ERR "%s: Error attempting to decrypt filename; " |
| 932 | "rc = [%d]\n", __func__, rc); |
| 933 | goto out_free_unlock; |
| 934 | } |
| 935 | s->i = 0; |
| 936 | while (s->decrypted_filename[s->i] != '\0' |
| 937 | && s->i < s->block_aligned_filename_size) |
| 938 | s->i++; |
| 939 | if (s->i == s->block_aligned_filename_size) { |
| 940 | printk(KERN_WARNING "%s: Invalid tag 70 packet; could not " |
| 941 | "find valid separator between random characters and " |
| 942 | "the filename\n", __func__); |
| 943 | rc = -EINVAL; |
| 944 | goto out_free_unlock; |
| 945 | } |
| 946 | s->i++; |
| 947 | (*filename_size) = (s->block_aligned_filename_size - s->i); |
| 948 | if (!((*filename_size) > 0 && (*filename_size < PATH_MAX))) { |
Michael Halcrow | df261c5 | 2009-01-06 14:42:02 -0800 | [diff] [blame] | 949 | printk(KERN_WARNING "%s: Filename size is [%zd], which is " |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 950 | "invalid\n", __func__, (*filename_size)); |
| 951 | rc = -EINVAL; |
| 952 | goto out_free_unlock; |
| 953 | } |
| 954 | (*filename) = kmalloc(((*filename_size) + 1), GFP_KERNEL); |
| 955 | if (!(*filename)) { |
| 956 | printk(KERN_ERR "%s: Out of memory whilst attempting to " |
Michael Halcrow | a8f1286 | 2009-01-06 14:42:03 -0800 | [diff] [blame] | 957 | "kmalloc [%zd] bytes\n", __func__, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 958 | ((*filename_size) + 1)); |
| 959 | rc = -ENOMEM; |
| 960 | goto out_free_unlock; |
| 961 | } |
| 962 | memcpy((*filename), &s->decrypted_filename[s->i], (*filename_size)); |
| 963 | (*filename)[(*filename_size)] = '\0'; |
| 964 | out_free_unlock: |
| 965 | kfree(s->decrypted_filename); |
| 966 | out_unlock: |
| 967 | mutex_unlock(s->tfm_mutex); |
| 968 | out: |
| 969 | if (rc) { |
| 970 | (*packet_size) = 0; |
| 971 | (*filename_size) = 0; |
| 972 | (*filename) = NULL; |
| 973 | } |
| 974 | kfree(s); |
| 975 | return rc; |
| 976 | } |
| 977 | |
| 978 | static int |
Michael Halcrow | cd9d67d | 2007-10-16 01:28:04 -0700 | [diff] [blame] | 979 | ecryptfs_get_auth_tok_sig(char **sig, struct ecryptfs_auth_tok *auth_tok) |
| 980 | { |
| 981 | int rc = 0; |
| 982 | |
| 983 | (*sig) = NULL; |
| 984 | switch (auth_tok->token_type) { |
| 985 | case ECRYPTFS_PASSWORD: |
| 986 | (*sig) = auth_tok->token.password.signature; |
| 987 | break; |
| 988 | case ECRYPTFS_PRIVATE_KEY: |
| 989 | (*sig) = auth_tok->token.private_key.signature; |
| 990 | break; |
| 991 | default: |
| 992 | printk(KERN_ERR "Cannot get sig for auth_tok of type [%d]\n", |
| 993 | auth_tok->token_type); |
| 994 | rc = -EINVAL; |
| 995 | } |
| 996 | return rc; |
| 997 | } |
| 998 | |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 999 | /** |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1000 | * decrypt_pki_encrypted_session_key - Decrypt the session key with the given auth_tok. |
| 1001 | * @auth_tok: The key authentication token used to decrypt the session key |
| 1002 | * @crypt_stat: The cryptographic context |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1003 | * |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1004 | * Returns zero on success; non-zero error otherwise. |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1005 | */ |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1006 | static int |
| 1007 | decrypt_pki_encrypted_session_key(struct ecryptfs_auth_tok *auth_tok, |
| 1008 | struct ecryptfs_crypt_stat *crypt_stat) |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1009 | { |
Trevor Highland | 19e66a6 | 2008-02-06 01:38:36 -0800 | [diff] [blame] | 1010 | u8 cipher_code = 0; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1011 | struct ecryptfs_msg_ctx *msg_ctx; |
| 1012 | struct ecryptfs_message *msg = NULL; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1013 | char *auth_tok_sig; |
Tyler Hicks | 624ae52 | 2008-10-15 22:02:51 -0700 | [diff] [blame] | 1014 | char *payload; |
| 1015 | size_t payload_len; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1016 | int rc; |
| 1017 | |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 1018 | rc = ecryptfs_get_auth_tok_sig(&auth_tok_sig, auth_tok); |
| 1019 | if (rc) { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1020 | printk(KERN_ERR "Unrecognized auth tok type: [%d]\n", |
| 1021 | auth_tok->token_type); |
| 1022 | goto out; |
| 1023 | } |
| 1024 | rc = write_tag_64_packet(auth_tok_sig, &(auth_tok->session_key), |
Tyler Hicks | 624ae52 | 2008-10-15 22:02:51 -0700 | [diff] [blame] | 1025 | &payload, &payload_len); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1026 | if (rc) { |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 1027 | ecryptfs_printk(KERN_ERR, "Failed to write tag 64 packet\n"); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1028 | goto out; |
| 1029 | } |
Tyler Hicks | 624ae52 | 2008-10-15 22:02:51 -0700 | [diff] [blame] | 1030 | rc = ecryptfs_send_message(payload, payload_len, &msg_ctx); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1031 | if (rc) { |
Tyler Hicks | 624ae52 | 2008-10-15 22:02:51 -0700 | [diff] [blame] | 1032 | ecryptfs_printk(KERN_ERR, "Error sending message to " |
| 1033 | "ecryptfsd\n"); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1034 | goto out; |
| 1035 | } |
| 1036 | rc = ecryptfs_wait_for_response(msg_ctx, &msg); |
| 1037 | if (rc) { |
| 1038 | ecryptfs_printk(KERN_ERR, "Failed to receive tag 65 packet " |
| 1039 | "from the user space daemon\n"); |
| 1040 | rc = -EIO; |
| 1041 | goto out; |
| 1042 | } |
| 1043 | rc = parse_tag_65_packet(&(auth_tok->session_key), |
| 1044 | &cipher_code, msg); |
| 1045 | if (rc) { |
| 1046 | printk(KERN_ERR "Failed to parse tag 65 packet; rc = [%d]\n", |
| 1047 | rc); |
| 1048 | goto out; |
| 1049 | } |
| 1050 | auth_tok->session_key.flags |= ECRYPTFS_CONTAINS_DECRYPTED_KEY; |
| 1051 | memcpy(crypt_stat->key, auth_tok->session_key.decrypted_key, |
| 1052 | auth_tok->session_key.decrypted_key_size); |
| 1053 | crypt_stat->key_size = auth_tok->session_key.decrypted_key_size; |
| 1054 | rc = ecryptfs_cipher_code_to_string(crypt_stat->cipher, cipher_code); |
| 1055 | if (rc) { |
| 1056 | ecryptfs_printk(KERN_ERR, "Cipher code [%d] is invalid\n", |
| 1057 | cipher_code) |
| 1058 | goto out; |
| 1059 | } |
| 1060 | crypt_stat->flags |= ECRYPTFS_KEY_VALID; |
| 1061 | if (ecryptfs_verbosity > 0) { |
| 1062 | ecryptfs_printk(KERN_DEBUG, "Decrypted session key:\n"); |
| 1063 | ecryptfs_dump_hex(crypt_stat->key, |
| 1064 | crypt_stat->key_size); |
| 1065 | } |
| 1066 | out: |
| 1067 | if (msg) |
| 1068 | kfree(msg); |
| 1069 | return rc; |
| 1070 | } |
| 1071 | |
| 1072 | static void wipe_auth_tok_list(struct list_head *auth_tok_list_head) |
| 1073 | { |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1074 | struct ecryptfs_auth_tok_list_item *auth_tok_list_item; |
Michael Halcrow | e0869cc | 2007-10-16 01:27:55 -0700 | [diff] [blame] | 1075 | struct ecryptfs_auth_tok_list_item *auth_tok_list_item_tmp; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1076 | |
Michael Halcrow | e0869cc | 2007-10-16 01:27:55 -0700 | [diff] [blame] | 1077 | list_for_each_entry_safe(auth_tok_list_item, auth_tok_list_item_tmp, |
| 1078 | auth_tok_list_head, list) { |
| 1079 | list_del(&auth_tok_list_item->list); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1080 | kmem_cache_free(ecryptfs_auth_tok_list_item_cache, |
| 1081 | auth_tok_list_item); |
| 1082 | } |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1083 | } |
| 1084 | |
| 1085 | struct kmem_cache *ecryptfs_auth_tok_list_item_cache; |
| 1086 | |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1087 | /** |
| 1088 | * parse_tag_1_packet |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1089 | * @crypt_stat: The cryptographic context to modify based on packet contents |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1090 | * @data: The raw bytes of the packet. |
| 1091 | * @auth_tok_list: eCryptfs parses packets into authentication tokens; |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1092 | * a new authentication token will be placed at the |
| 1093 | * end of this list for this packet. |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1094 | * @new_auth_tok: Pointer to a pointer to memory that this function |
| 1095 | * allocates; sets the memory address of the pointer to |
| 1096 | * NULL on error. This object is added to the |
| 1097 | * auth_tok_list. |
| 1098 | * @packet_size: This function writes the size of the parsed packet |
| 1099 | * into this memory location; zero on error. |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1100 | * @max_packet_size: The maximum allowable packet size |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1101 | * |
| 1102 | * Returns zero on success; non-zero on error. |
| 1103 | */ |
| 1104 | static int |
| 1105 | parse_tag_1_packet(struct ecryptfs_crypt_stat *crypt_stat, |
| 1106 | unsigned char *data, struct list_head *auth_tok_list, |
| 1107 | struct ecryptfs_auth_tok **new_auth_tok, |
| 1108 | size_t *packet_size, size_t max_packet_size) |
| 1109 | { |
| 1110 | size_t body_size; |
| 1111 | struct ecryptfs_auth_tok_list_item *auth_tok_list_item; |
| 1112 | size_t length_size; |
| 1113 | int rc = 0; |
| 1114 | |
| 1115 | (*packet_size) = 0; |
| 1116 | (*new_auth_tok) = NULL; |
Michael Halcrow | 1321817 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1117 | /** |
| 1118 | * This format is inspired by OpenPGP; see RFC 2440 |
| 1119 | * packet tag 1 |
| 1120 | * |
| 1121 | * Tag 1 identifier (1 byte) |
| 1122 | * Max Tag 1 packet size (max 3 bytes) |
| 1123 | * Version (1 byte) |
| 1124 | * Key identifier (8 bytes; ECRYPTFS_SIG_SIZE) |
| 1125 | * Cipher identifier (1 byte) |
| 1126 | * Encrypted key size (arbitrary) |
| 1127 | * |
| 1128 | * 12 bytes minimum packet size |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1129 | */ |
Michael Halcrow | 1321817 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1130 | if (unlikely(max_packet_size < 12)) { |
| 1131 | printk(KERN_ERR "Invalid max packet size; must be >=12\n"); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1132 | rc = -EINVAL; |
| 1133 | goto out; |
| 1134 | } |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1135 | if (data[(*packet_size)++] != ECRYPTFS_TAG_1_PACKET_TYPE) { |
Michael Halcrow | 1321817 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1136 | printk(KERN_ERR "Enter w/ first byte != 0x%.2x\n", |
| 1137 | ECRYPTFS_TAG_1_PACKET_TYPE); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1138 | rc = -EINVAL; |
| 1139 | goto out; |
| 1140 | } |
| 1141 | /* Released: wipe_auth_tok_list called in ecryptfs_parse_packet_set or |
| 1142 | * at end of function upon failure */ |
| 1143 | auth_tok_list_item = |
Michael Halcrow | 1321817 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1144 | kmem_cache_zalloc(ecryptfs_auth_tok_list_item_cache, |
| 1145 | GFP_KERNEL); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1146 | if (!auth_tok_list_item) { |
Michael Halcrow | 1321817 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1147 | printk(KERN_ERR "Unable to allocate memory\n"); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1148 | rc = -ENOMEM; |
| 1149 | goto out; |
| 1150 | } |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1151 | (*new_auth_tok) = &auth_tok_list_item->auth_tok; |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 1152 | rc = ecryptfs_parse_packet_length(&data[(*packet_size)], &body_size, |
| 1153 | &length_size); |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 1154 | if (rc) { |
Michael Halcrow | 1321817 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1155 | printk(KERN_WARNING "Error parsing packet length; " |
| 1156 | "rc = [%d]\n", rc); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1157 | goto out_free; |
| 1158 | } |
Michael Halcrow | 1321817 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1159 | if (unlikely(body_size < (ECRYPTFS_SIG_SIZE + 2))) { |
Andrew Morton | 81acbcd | 2007-10-16 01:27:59 -0700 | [diff] [blame] | 1160 | printk(KERN_WARNING "Invalid body size ([%td])\n", body_size); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1161 | rc = -EINVAL; |
| 1162 | goto out_free; |
| 1163 | } |
| 1164 | (*packet_size) += length_size; |
| 1165 | if (unlikely((*packet_size) + body_size > max_packet_size)) { |
Michael Halcrow | 1321817 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1166 | printk(KERN_WARNING "Packet size exceeds max\n"); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1167 | rc = -EINVAL; |
| 1168 | goto out_free; |
| 1169 | } |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1170 | if (unlikely(data[(*packet_size)++] != 0x03)) { |
Michael Halcrow | 1321817 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1171 | printk(KERN_WARNING "Unknown version number [%d]\n", |
| 1172 | data[(*packet_size) - 1]); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1173 | rc = -EINVAL; |
| 1174 | goto out_free; |
| 1175 | } |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1176 | ecryptfs_to_hex((*new_auth_tok)->token.private_key.signature, |
| 1177 | &data[(*packet_size)], ECRYPTFS_SIG_SIZE); |
| 1178 | *packet_size += ECRYPTFS_SIG_SIZE; |
| 1179 | /* This byte is skipped because the kernel does not need to |
| 1180 | * know which public key encryption algorithm was used */ |
| 1181 | (*packet_size)++; |
| 1182 | (*new_auth_tok)->session_key.encrypted_key_size = |
Michael Halcrow | 1321817 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1183 | body_size - (ECRYPTFS_SIG_SIZE + 2); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1184 | if ((*new_auth_tok)->session_key.encrypted_key_size |
| 1185 | > ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES) { |
Michael Halcrow | 1321817 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1186 | printk(KERN_WARNING "Tag 1 packet contains key larger " |
| 1187 | "than ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES"); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1188 | rc = -EINVAL; |
| 1189 | goto out; |
| 1190 | } |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1191 | memcpy((*new_auth_tok)->session_key.encrypted_key, |
Michael Halcrow | 1321817 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1192 | &data[(*packet_size)], (body_size - (ECRYPTFS_SIG_SIZE + 2))); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1193 | (*packet_size) += (*new_auth_tok)->session_key.encrypted_key_size; |
| 1194 | (*new_auth_tok)->session_key.flags &= |
| 1195 | ~ECRYPTFS_CONTAINS_DECRYPTED_KEY; |
| 1196 | (*new_auth_tok)->session_key.flags |= |
| 1197 | ECRYPTFS_CONTAINS_ENCRYPTED_KEY; |
| 1198 | (*new_auth_tok)->token_type = ECRYPTFS_PRIVATE_KEY; |
Michael Halcrow | 1321817 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1199 | (*new_auth_tok)->flags = 0; |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 1200 | (*new_auth_tok)->session_key.flags &= |
| 1201 | ~(ECRYPTFS_USERSPACE_SHOULD_TRY_TO_DECRYPT); |
| 1202 | (*new_auth_tok)->session_key.flags &= |
| 1203 | ~(ECRYPTFS_USERSPACE_SHOULD_TRY_TO_ENCRYPT); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1204 | list_add(&auth_tok_list_item->list, auth_tok_list); |
| 1205 | goto out; |
| 1206 | out_free: |
| 1207 | (*new_auth_tok) = NULL; |
| 1208 | memset(auth_tok_list_item, 0, |
| 1209 | sizeof(struct ecryptfs_auth_tok_list_item)); |
| 1210 | kmem_cache_free(ecryptfs_auth_tok_list_item_cache, |
| 1211 | auth_tok_list_item); |
| 1212 | out: |
| 1213 | if (rc) |
| 1214 | (*packet_size) = 0; |
| 1215 | return rc; |
| 1216 | } |
| 1217 | |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1218 | /** |
| 1219 | * parse_tag_3_packet |
| 1220 | * @crypt_stat: The cryptographic context to modify based on packet |
| 1221 | * contents. |
| 1222 | * @data: The raw bytes of the packet. |
| 1223 | * @auth_tok_list: eCryptfs parses packets into authentication tokens; |
| 1224 | * a new authentication token will be placed at the end |
| 1225 | * of this list for this packet. |
| 1226 | * @new_auth_tok: Pointer to a pointer to memory that this function |
| 1227 | * allocates; sets the memory address of the pointer to |
| 1228 | * NULL on error. This object is added to the |
| 1229 | * auth_tok_list. |
| 1230 | * @packet_size: This function writes the size of the parsed packet |
| 1231 | * into this memory location; zero on error. |
| 1232 | * @max_packet_size: maximum number of bytes to parse |
| 1233 | * |
| 1234 | * Returns zero on success; non-zero on error. |
| 1235 | */ |
| 1236 | static int |
| 1237 | parse_tag_3_packet(struct ecryptfs_crypt_stat *crypt_stat, |
| 1238 | unsigned char *data, struct list_head *auth_tok_list, |
| 1239 | struct ecryptfs_auth_tok **new_auth_tok, |
| 1240 | size_t *packet_size, size_t max_packet_size) |
| 1241 | { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1242 | size_t body_size; |
| 1243 | struct ecryptfs_auth_tok_list_item *auth_tok_list_item; |
| 1244 | size_t length_size; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1245 | int rc = 0; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1246 | |
| 1247 | (*packet_size) = 0; |
| 1248 | (*new_auth_tok) = NULL; |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1249 | /** |
| 1250 | *This format is inspired by OpenPGP; see RFC 2440 |
| 1251 | * packet tag 3 |
| 1252 | * |
| 1253 | * Tag 3 identifier (1 byte) |
| 1254 | * Max Tag 3 packet size (max 3 bytes) |
| 1255 | * Version (1 byte) |
| 1256 | * Cipher code (1 byte) |
| 1257 | * S2K specifier (1 byte) |
| 1258 | * Hash identifier (1 byte) |
| 1259 | * Salt (ECRYPTFS_SALT_SIZE) |
| 1260 | * Hash iterations (1 byte) |
| 1261 | * Encrypted key (arbitrary) |
| 1262 | * |
| 1263 | * (ECRYPTFS_SALT_SIZE + 7) minimum packet size |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1264 | */ |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1265 | if (max_packet_size < (ECRYPTFS_SALT_SIZE + 7)) { |
| 1266 | printk(KERN_ERR "Max packet size too large\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1267 | rc = -EINVAL; |
| 1268 | goto out; |
| 1269 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1270 | if (data[(*packet_size)++] != ECRYPTFS_TAG_3_PACKET_TYPE) { |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1271 | printk(KERN_ERR "First byte != 0x%.2x; invalid packet\n", |
| 1272 | ECRYPTFS_TAG_3_PACKET_TYPE); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1273 | rc = -EINVAL; |
| 1274 | goto out; |
| 1275 | } |
| 1276 | /* Released: wipe_auth_tok_list called in ecryptfs_parse_packet_set or |
| 1277 | * at end of function upon failure */ |
| 1278 | auth_tok_list_item = |
Robert P. J. Day | c376222 | 2007-02-10 01:45:03 -0800 | [diff] [blame] | 1279 | kmem_cache_zalloc(ecryptfs_auth_tok_list_item_cache, GFP_KERNEL); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1280 | if (!auth_tok_list_item) { |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1281 | printk(KERN_ERR "Unable to allocate memory\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1282 | rc = -ENOMEM; |
| 1283 | goto out; |
| 1284 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1285 | (*new_auth_tok) = &auth_tok_list_item->auth_tok; |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 1286 | rc = ecryptfs_parse_packet_length(&data[(*packet_size)], &body_size, |
| 1287 | &length_size); |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 1288 | if (rc) { |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1289 | printk(KERN_WARNING "Error parsing packet length; rc = [%d]\n", |
| 1290 | rc); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1291 | goto out_free; |
| 1292 | } |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1293 | if (unlikely(body_size < (ECRYPTFS_SALT_SIZE + 5))) { |
Andrew Morton | 81acbcd | 2007-10-16 01:27:59 -0700 | [diff] [blame] | 1294 | printk(KERN_WARNING "Invalid body size ([%td])\n", body_size); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1295 | rc = -EINVAL; |
| 1296 | goto out_free; |
| 1297 | } |
| 1298 | (*packet_size) += length_size; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1299 | if (unlikely((*packet_size) + body_size > max_packet_size)) { |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1300 | printk(KERN_ERR "Packet size exceeds max\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1301 | rc = -EINVAL; |
| 1302 | goto out_free; |
| 1303 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1304 | (*new_auth_tok)->session_key.encrypted_key_size = |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1305 | (body_size - (ECRYPTFS_SALT_SIZE + 5)); |
Ramon de Carvalho Valle | f151cd2 | 2009-07-28 13:58:22 -0500 | [diff] [blame] | 1306 | if ((*new_auth_tok)->session_key.encrypted_key_size |
| 1307 | > ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES) { |
| 1308 | printk(KERN_WARNING "Tag 3 packet contains key larger " |
| 1309 | "than ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES\n"); |
| 1310 | rc = -EINVAL; |
| 1311 | goto out_free; |
| 1312 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1313 | if (unlikely(data[(*packet_size)++] != 0x04)) { |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1314 | printk(KERN_WARNING "Unknown version number [%d]\n", |
| 1315 | data[(*packet_size) - 1]); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1316 | rc = -EINVAL; |
| 1317 | goto out_free; |
| 1318 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1319 | ecryptfs_cipher_code_to_string(crypt_stat->cipher, |
| 1320 | (u16)data[(*packet_size)]); |
| 1321 | /* A little extra work to differentiate among the AES key |
| 1322 | * sizes; see RFC2440 */ |
| 1323 | switch(data[(*packet_size)++]) { |
| 1324 | case RFC2440_CIPHER_AES_192: |
| 1325 | crypt_stat->key_size = 24; |
| 1326 | break; |
| 1327 | default: |
| 1328 | crypt_stat->key_size = |
| 1329 | (*new_auth_tok)->session_key.encrypted_key_size; |
| 1330 | } |
| 1331 | ecryptfs_init_crypt_ctx(crypt_stat); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1332 | if (unlikely(data[(*packet_size)++] != 0x03)) { |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1333 | printk(KERN_WARNING "Only S2K ID 3 is currently supported\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1334 | rc = -ENOSYS; |
| 1335 | goto out_free; |
| 1336 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1337 | /* TODO: finish the hash mapping */ |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1338 | switch (data[(*packet_size)++]) { |
| 1339 | case 0x01: /* See RFC2440 for these numbers and their mappings */ |
| 1340 | /* Choose MD5 */ |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1341 | memcpy((*new_auth_tok)->token.password.salt, |
| 1342 | &data[(*packet_size)], ECRYPTFS_SALT_SIZE); |
| 1343 | (*packet_size) += ECRYPTFS_SALT_SIZE; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1344 | /* This conversion was taken straight from RFC2440 */ |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1345 | (*new_auth_tok)->token.password.hash_iterations = |
| 1346 | ((u32) 16 + (data[(*packet_size)] & 15)) |
| 1347 | << ((data[(*packet_size)] >> 4) + 6); |
| 1348 | (*packet_size)++; |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1349 | /* Friendly reminder: |
| 1350 | * (*new_auth_tok)->session_key.encrypted_key_size = |
| 1351 | * (body_size - (ECRYPTFS_SALT_SIZE + 5)); */ |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1352 | memcpy((*new_auth_tok)->session_key.encrypted_key, |
| 1353 | &data[(*packet_size)], |
| 1354 | (*new_auth_tok)->session_key.encrypted_key_size); |
| 1355 | (*packet_size) += |
| 1356 | (*new_auth_tok)->session_key.encrypted_key_size; |
| 1357 | (*new_auth_tok)->session_key.flags &= |
| 1358 | ~ECRYPTFS_CONTAINS_DECRYPTED_KEY; |
| 1359 | (*new_auth_tok)->session_key.flags |= |
| 1360 | ECRYPTFS_CONTAINS_ENCRYPTED_KEY; |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1361 | (*new_auth_tok)->token.password.hash_algo = 0x01; /* MD5 */ |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1362 | break; |
| 1363 | default: |
| 1364 | ecryptfs_printk(KERN_ERR, "Unsupported hash algorithm: " |
| 1365 | "[%d]\n", data[(*packet_size) - 1]); |
| 1366 | rc = -ENOSYS; |
| 1367 | goto out_free; |
| 1368 | } |
| 1369 | (*new_auth_tok)->token_type = ECRYPTFS_PASSWORD; |
| 1370 | /* TODO: Parametarize; we might actually want userspace to |
| 1371 | * decrypt the session key. */ |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 1372 | (*new_auth_tok)->session_key.flags &= |
| 1373 | ~(ECRYPTFS_USERSPACE_SHOULD_TRY_TO_DECRYPT); |
| 1374 | (*new_auth_tok)->session_key.flags &= |
| 1375 | ~(ECRYPTFS_USERSPACE_SHOULD_TRY_TO_ENCRYPT); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1376 | list_add(&auth_tok_list_item->list, auth_tok_list); |
| 1377 | goto out; |
| 1378 | out_free: |
| 1379 | (*new_auth_tok) = NULL; |
| 1380 | memset(auth_tok_list_item, 0, |
| 1381 | sizeof(struct ecryptfs_auth_tok_list_item)); |
| 1382 | kmem_cache_free(ecryptfs_auth_tok_list_item_cache, |
| 1383 | auth_tok_list_item); |
| 1384 | out: |
| 1385 | if (rc) |
| 1386 | (*packet_size) = 0; |
| 1387 | return rc; |
| 1388 | } |
| 1389 | |
| 1390 | /** |
| 1391 | * parse_tag_11_packet |
| 1392 | * @data: The raw bytes of the packet |
| 1393 | * @contents: This function writes the data contents of the literal |
| 1394 | * packet into this memory location |
| 1395 | * @max_contents_bytes: The maximum number of bytes that this function |
| 1396 | * is allowed to write into contents |
| 1397 | * @tag_11_contents_size: This function writes the size of the parsed |
| 1398 | * contents into this memory location; zero on |
| 1399 | * error |
| 1400 | * @packet_size: This function writes the size of the parsed packet |
| 1401 | * into this memory location; zero on error |
| 1402 | * @max_packet_size: maximum number of bytes to parse |
| 1403 | * |
| 1404 | * Returns zero on success; non-zero on error. |
| 1405 | */ |
| 1406 | static int |
| 1407 | parse_tag_11_packet(unsigned char *data, unsigned char *contents, |
| 1408 | size_t max_contents_bytes, size_t *tag_11_contents_size, |
| 1409 | size_t *packet_size, size_t max_packet_size) |
| 1410 | { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1411 | size_t body_size; |
| 1412 | size_t length_size; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1413 | int rc = 0; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1414 | |
| 1415 | (*packet_size) = 0; |
| 1416 | (*tag_11_contents_size) = 0; |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1417 | /* This format is inspired by OpenPGP; see RFC 2440 |
| 1418 | * packet tag 11 |
| 1419 | * |
| 1420 | * Tag 11 identifier (1 byte) |
| 1421 | * Max Tag 11 packet size (max 3 bytes) |
| 1422 | * Binary format specifier (1 byte) |
| 1423 | * Filename length (1 byte) |
| 1424 | * Filename ("_CONSOLE") (8 bytes) |
| 1425 | * Modification date (4 bytes) |
| 1426 | * Literal data (arbitrary) |
| 1427 | * |
| 1428 | * We need at least 16 bytes of data for the packet to even be |
| 1429 | * valid. |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1430 | */ |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1431 | if (max_packet_size < 16) { |
| 1432 | printk(KERN_ERR "Maximum packet size too small\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1433 | rc = -EINVAL; |
| 1434 | goto out; |
| 1435 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1436 | if (data[(*packet_size)++] != ECRYPTFS_TAG_11_PACKET_TYPE) { |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1437 | printk(KERN_WARNING "Invalid tag 11 packet format\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1438 | rc = -EINVAL; |
| 1439 | goto out; |
| 1440 | } |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 1441 | rc = ecryptfs_parse_packet_length(&data[(*packet_size)], &body_size, |
| 1442 | &length_size); |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 1443 | if (rc) { |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1444 | printk(KERN_WARNING "Invalid tag 11 packet format\n"); |
| 1445 | goto out; |
| 1446 | } |
| 1447 | if (body_size < 14) { |
Andrew Morton | 81acbcd | 2007-10-16 01:27:59 -0700 | [diff] [blame] | 1448 | printk(KERN_WARNING "Invalid body size ([%td])\n", body_size); |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1449 | rc = -EINVAL; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1450 | goto out; |
| 1451 | } |
| 1452 | (*packet_size) += length_size; |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1453 | (*tag_11_contents_size) = (body_size - 14); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1454 | if (unlikely((*packet_size) + body_size + 1 > max_packet_size)) { |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1455 | printk(KERN_ERR "Packet size exceeds max\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1456 | rc = -EINVAL; |
| 1457 | goto out; |
| 1458 | } |
Tyler Hicks | 6352a29 | 2009-07-28 13:57:01 -0500 | [diff] [blame] | 1459 | if (unlikely((*tag_11_contents_size) > max_contents_bytes)) { |
| 1460 | printk(KERN_ERR "Literal data section in tag 11 packet exceeds " |
| 1461 | "expected size\n"); |
| 1462 | rc = -EINVAL; |
| 1463 | goto out; |
| 1464 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1465 | if (data[(*packet_size)++] != 0x62) { |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1466 | printk(KERN_WARNING "Unrecognizable packet\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1467 | rc = -EINVAL; |
| 1468 | goto out; |
| 1469 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1470 | if (data[(*packet_size)++] != 0x08) { |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1471 | printk(KERN_WARNING "Unrecognizable packet\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1472 | rc = -EINVAL; |
| 1473 | goto out; |
| 1474 | } |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1475 | (*packet_size) += 12; /* Ignore filename and modification date */ |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1476 | memcpy(contents, &data[(*packet_size)], (*tag_11_contents_size)); |
| 1477 | (*packet_size) += (*tag_11_contents_size); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1478 | out: |
| 1479 | if (rc) { |
| 1480 | (*packet_size) = 0; |
| 1481 | (*tag_11_contents_size) = 0; |
| 1482 | } |
| 1483 | return rc; |
| 1484 | } |
| 1485 | |
| 1486 | /** |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1487 | * ecryptfs_verify_version |
| 1488 | * @version: The version number to confirm |
| 1489 | * |
| 1490 | * Returns zero on good version; non-zero otherwise |
| 1491 | */ |
| 1492 | static int ecryptfs_verify_version(u16 version) |
| 1493 | { |
| 1494 | int rc = 0; |
| 1495 | unsigned char major; |
| 1496 | unsigned char minor; |
| 1497 | |
| 1498 | major = ((version >> 8) & 0xFF); |
| 1499 | minor = (version & 0xFF); |
| 1500 | if (major != ECRYPTFS_VERSION_MAJOR) { |
| 1501 | ecryptfs_printk(KERN_ERR, "Major version number mismatch. " |
| 1502 | "Expected [%d]; got [%d]\n", |
| 1503 | ECRYPTFS_VERSION_MAJOR, major); |
| 1504 | rc = -EINVAL; |
| 1505 | goto out; |
| 1506 | } |
| 1507 | if (minor != ECRYPTFS_VERSION_MINOR) { |
| 1508 | ecryptfs_printk(KERN_ERR, "Minor version number mismatch. " |
| 1509 | "Expected [%d]; got [%d]\n", |
| 1510 | ECRYPTFS_VERSION_MINOR, minor); |
| 1511 | rc = -EINVAL; |
| 1512 | goto out; |
| 1513 | } |
| 1514 | out: |
| 1515 | return rc; |
| 1516 | } |
| 1517 | |
| 1518 | int ecryptfs_keyring_auth_tok_for_sig(struct key **auth_tok_key, |
| 1519 | struct ecryptfs_auth_tok **auth_tok, |
| 1520 | char *sig) |
| 1521 | { |
| 1522 | int rc = 0; |
| 1523 | |
| 1524 | (*auth_tok_key) = request_key(&key_type_user, sig, NULL); |
| 1525 | if (!(*auth_tok_key) || IS_ERR(*auth_tok_key)) { |
| 1526 | printk(KERN_ERR "Could not find key with description: [%s]\n", |
| 1527 | sig); |
Eric Sandeen | 982363c | 2008-07-23 21:30:04 -0700 | [diff] [blame] | 1528 | rc = process_request_key_err(PTR_ERR(*auth_tok_key)); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1529 | goto out; |
| 1530 | } |
| 1531 | (*auth_tok) = ecryptfs_get_key_payload_data(*auth_tok_key); |
| 1532 | if (ecryptfs_verify_version((*auth_tok)->version)) { |
| 1533 | printk(KERN_ERR |
| 1534 | "Data structure version mismatch. " |
| 1535 | "Userspace tools must match eCryptfs " |
| 1536 | "kernel module with major version [%d] " |
| 1537 | "and minor version [%d]\n", |
| 1538 | ECRYPTFS_VERSION_MAJOR, |
| 1539 | ECRYPTFS_VERSION_MINOR); |
| 1540 | rc = -EINVAL; |
| 1541 | goto out; |
| 1542 | } |
| 1543 | if ((*auth_tok)->token_type != ECRYPTFS_PASSWORD |
| 1544 | && (*auth_tok)->token_type != ECRYPTFS_PRIVATE_KEY) { |
| 1545 | printk(KERN_ERR "Invalid auth_tok structure " |
| 1546 | "returned from key query\n"); |
| 1547 | rc = -EINVAL; |
| 1548 | goto out; |
| 1549 | } |
| 1550 | out: |
| 1551 | return rc; |
| 1552 | } |
| 1553 | |
| 1554 | /** |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1555 | * decrypt_passphrase_encrypted_session_key - Decrypt the session key with the given auth_tok. |
| 1556 | * @auth_tok: The passphrase authentication token to use to encrypt the FEK |
| 1557 | * @crypt_stat: The cryptographic context |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1558 | * |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1559 | * Returns zero on success; non-zero error otherwise |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1560 | */ |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1561 | static int |
| 1562 | decrypt_passphrase_encrypted_session_key(struct ecryptfs_auth_tok *auth_tok, |
| 1563 | struct ecryptfs_crypt_stat *crypt_stat) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1564 | { |
Michael Halcrow | ac97b9f | 2008-11-19 15:36:28 -0800 | [diff] [blame] | 1565 | struct scatterlist dst_sg[2]; |
| 1566 | struct scatterlist src_sg[2]; |
Michael Halcrow | dd8e290 | 2007-10-16 01:28:03 -0700 | [diff] [blame] | 1567 | struct mutex *tfm_mutex; |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 1568 | struct blkcipher_desc desc = { |
| 1569 | .flags = CRYPTO_TFM_REQ_MAY_SLEEP |
| 1570 | }; |
| 1571 | int rc = 0; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1572 | |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1573 | if (unlikely(ecryptfs_verbosity > 0)) { |
| 1574 | ecryptfs_printk( |
| 1575 | KERN_DEBUG, "Session key encryption key (size [%d]):\n", |
| 1576 | auth_tok->token.password.session_key_encryption_key_bytes); |
| 1577 | ecryptfs_dump_hex( |
| 1578 | auth_tok->token.password.session_key_encryption_key, |
| 1579 | auth_tok->token.password.session_key_encryption_key_bytes); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1580 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1581 | rc = ecryptfs_get_tfm_and_mutex_for_cipher_name(&desc.tfm, &tfm_mutex, |
| 1582 | crypt_stat->cipher); |
| 1583 | if (unlikely(rc)) { |
| 1584 | printk(KERN_ERR "Internal error whilst attempting to get " |
| 1585 | "tfm and mutex for cipher name [%s]; rc = [%d]\n", |
| 1586 | crypt_stat->cipher, rc); |
| 1587 | goto out; |
| 1588 | } |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 1589 | rc = virt_to_scatterlist(auth_tok->session_key.encrypted_key, |
| 1590 | auth_tok->session_key.encrypted_key_size, |
Michael Halcrow | ac97b9f | 2008-11-19 15:36:28 -0800 | [diff] [blame] | 1591 | src_sg, 2); |
| 1592 | if (rc < 1 || rc > 2) { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1593 | printk(KERN_ERR "Internal error whilst attempting to convert " |
| 1594 | "auth_tok->session_key.encrypted_key to scatterlist; " |
| 1595 | "expected rc = 1; got rc = [%d]. " |
| 1596 | "auth_tok->session_key.encrypted_key_size = [%d]\n", rc, |
| 1597 | auth_tok->session_key.encrypted_key_size); |
| 1598 | goto out; |
| 1599 | } |
| 1600 | auth_tok->session_key.decrypted_key_size = |
| 1601 | auth_tok->session_key.encrypted_key_size; |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 1602 | rc = virt_to_scatterlist(auth_tok->session_key.decrypted_key, |
| 1603 | auth_tok->session_key.decrypted_key_size, |
Michael Halcrow | ac97b9f | 2008-11-19 15:36:28 -0800 | [diff] [blame] | 1604 | dst_sg, 2); |
| 1605 | if (rc < 1 || rc > 2) { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1606 | printk(KERN_ERR "Internal error whilst attempting to convert " |
| 1607 | "auth_tok->session_key.decrypted_key to scatterlist; " |
| 1608 | "expected rc = 1; got rc = [%d]\n", rc); |
| 1609 | goto out; |
| 1610 | } |
| 1611 | mutex_lock(tfm_mutex); |
| 1612 | rc = crypto_blkcipher_setkey( |
| 1613 | desc.tfm, auth_tok->token.password.session_key_encryption_key, |
| 1614 | crypt_stat->key_size); |
| 1615 | if (unlikely(rc < 0)) { |
| 1616 | mutex_unlock(tfm_mutex); |
Michael Halcrow | e5d9cbd | 2006-10-30 22:07:16 -0800 | [diff] [blame] | 1617 | printk(KERN_ERR "Error setting key for crypto context\n"); |
| 1618 | rc = -EINVAL; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1619 | goto out; |
Michael Halcrow | e5d9cbd | 2006-10-30 22:07:16 -0800 | [diff] [blame] | 1620 | } |
Michael Halcrow | ac97b9f | 2008-11-19 15:36:28 -0800 | [diff] [blame] | 1621 | rc = crypto_blkcipher_decrypt(&desc, dst_sg, src_sg, |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 1622 | auth_tok->session_key.encrypted_key_size); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1623 | mutex_unlock(tfm_mutex); |
| 1624 | if (unlikely(rc)) { |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 1625 | printk(KERN_ERR "Error decrypting; rc = [%d]\n", rc); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1626 | goto out; |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 1627 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1628 | auth_tok->session_key.flags |= ECRYPTFS_CONTAINS_DECRYPTED_KEY; |
| 1629 | memcpy(crypt_stat->key, auth_tok->session_key.decrypted_key, |
| 1630 | auth_tok->session_key.decrypted_key_size); |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 1631 | crypt_stat->flags |= ECRYPTFS_KEY_VALID; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1632 | if (unlikely(ecryptfs_verbosity > 0)) { |
| 1633 | ecryptfs_printk(KERN_DEBUG, "FEK of size [%d]:\n", |
| 1634 | crypt_stat->key_size); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1635 | ecryptfs_dump_hex(crypt_stat->key, |
| 1636 | crypt_stat->key_size); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1637 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1638 | out: |
| 1639 | return rc; |
| 1640 | } |
| 1641 | |
| 1642 | /** |
| 1643 | * ecryptfs_parse_packet_set |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1644 | * @crypt_stat: The cryptographic context |
| 1645 | * @src: Virtual address of region of memory containing the packets |
| 1646 | * @ecryptfs_dentry: The eCryptfs dentry associated with the packet set |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1647 | * |
| 1648 | * Get crypt_stat to have the file's session key if the requisite key |
| 1649 | * is available to decrypt the session key. |
| 1650 | * |
| 1651 | * Returns Zero if a valid authentication token was retrieved and |
| 1652 | * processed; negative value for file not encrypted or for error |
| 1653 | * conditions. |
| 1654 | */ |
| 1655 | int ecryptfs_parse_packet_set(struct ecryptfs_crypt_stat *crypt_stat, |
| 1656 | unsigned char *src, |
| 1657 | struct dentry *ecryptfs_dentry) |
| 1658 | { |
| 1659 | size_t i = 0; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1660 | size_t found_auth_tok; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1661 | size_t next_packet_is_auth_tok_packet; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1662 | struct list_head auth_tok_list; |
Michael Halcrow | dd8e290 | 2007-10-16 01:28:03 -0700 | [diff] [blame] | 1663 | struct ecryptfs_auth_tok *matching_auth_tok; |
| 1664 | struct ecryptfs_auth_tok *candidate_auth_tok; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1665 | char *candidate_auth_tok_sig; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1666 | size_t packet_size; |
| 1667 | struct ecryptfs_auth_tok *new_auth_tok; |
| 1668 | unsigned char sig_tmp_space[ECRYPTFS_SIG_SIZE]; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1669 | struct ecryptfs_auth_tok_list_item *auth_tok_list_item; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1670 | size_t tag_11_contents_size; |
| 1671 | size_t tag_11_packet_size; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1672 | int rc = 0; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1673 | |
| 1674 | INIT_LIST_HEAD(&auth_tok_list); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1675 | /* Parse the header to find as many packets as we can; these will be |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1676 | * added the our &auth_tok_list */ |
| 1677 | next_packet_is_auth_tok_packet = 1; |
| 1678 | while (next_packet_is_auth_tok_packet) { |
| 1679 | size_t max_packet_size = ((PAGE_CACHE_SIZE - 8) - i); |
| 1680 | |
| 1681 | switch (src[i]) { |
| 1682 | case ECRYPTFS_TAG_3_PACKET_TYPE: |
| 1683 | rc = parse_tag_3_packet(crypt_stat, |
| 1684 | (unsigned char *)&src[i], |
| 1685 | &auth_tok_list, &new_auth_tok, |
| 1686 | &packet_size, max_packet_size); |
| 1687 | if (rc) { |
| 1688 | ecryptfs_printk(KERN_ERR, "Error parsing " |
| 1689 | "tag 3 packet\n"); |
| 1690 | rc = -EIO; |
| 1691 | goto out_wipe_list; |
| 1692 | } |
| 1693 | i += packet_size; |
| 1694 | rc = parse_tag_11_packet((unsigned char *)&src[i], |
| 1695 | sig_tmp_space, |
| 1696 | ECRYPTFS_SIG_SIZE, |
| 1697 | &tag_11_contents_size, |
| 1698 | &tag_11_packet_size, |
| 1699 | max_packet_size); |
| 1700 | if (rc) { |
| 1701 | ecryptfs_printk(KERN_ERR, "No valid " |
| 1702 | "(ecryptfs-specific) literal " |
| 1703 | "packet containing " |
| 1704 | "authentication token " |
| 1705 | "signature found after " |
| 1706 | "tag 3 packet\n"); |
| 1707 | rc = -EIO; |
| 1708 | goto out_wipe_list; |
| 1709 | } |
| 1710 | i += tag_11_packet_size; |
| 1711 | if (ECRYPTFS_SIG_SIZE != tag_11_contents_size) { |
| 1712 | ecryptfs_printk(KERN_ERR, "Expected " |
| 1713 | "signature of size [%d]; " |
| 1714 | "read size [%d]\n", |
| 1715 | ECRYPTFS_SIG_SIZE, |
| 1716 | tag_11_contents_size); |
| 1717 | rc = -EIO; |
| 1718 | goto out_wipe_list; |
| 1719 | } |
| 1720 | ecryptfs_to_hex(new_auth_tok->token.password.signature, |
| 1721 | sig_tmp_space, tag_11_contents_size); |
| 1722 | new_auth_tok->token.password.signature[ |
| 1723 | ECRYPTFS_PASSWORD_SIG_SIZE] = '\0'; |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 1724 | crypt_stat->flags |= ECRYPTFS_ENCRYPTED; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1725 | break; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1726 | case ECRYPTFS_TAG_1_PACKET_TYPE: |
| 1727 | rc = parse_tag_1_packet(crypt_stat, |
| 1728 | (unsigned char *)&src[i], |
| 1729 | &auth_tok_list, &new_auth_tok, |
| 1730 | &packet_size, max_packet_size); |
| 1731 | if (rc) { |
| 1732 | ecryptfs_printk(KERN_ERR, "Error parsing " |
| 1733 | "tag 1 packet\n"); |
| 1734 | rc = -EIO; |
| 1735 | goto out_wipe_list; |
| 1736 | } |
| 1737 | i += packet_size; |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 1738 | crypt_stat->flags |= ECRYPTFS_ENCRYPTED; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1739 | break; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1740 | case ECRYPTFS_TAG_11_PACKET_TYPE: |
| 1741 | ecryptfs_printk(KERN_WARNING, "Invalid packet set " |
| 1742 | "(Tag 11 not allowed by itself)\n"); |
| 1743 | rc = -EIO; |
| 1744 | goto out_wipe_list; |
| 1745 | break; |
| 1746 | default: |
| 1747 | ecryptfs_printk(KERN_DEBUG, "No packet at offset " |
| 1748 | "[%d] of the file header; hex value of " |
| 1749 | "character is [0x%.2x]\n", i, src[i]); |
| 1750 | next_packet_is_auth_tok_packet = 0; |
| 1751 | } |
| 1752 | } |
| 1753 | if (list_empty(&auth_tok_list)) { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1754 | printk(KERN_ERR "The lower file appears to be a non-encrypted " |
| 1755 | "eCryptfs file; this is not supported in this version " |
| 1756 | "of the eCryptfs kernel module\n"); |
| 1757 | rc = -EINVAL; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1758 | goto out; |
| 1759 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1760 | /* auth_tok_list contains the set of authentication tokens |
| 1761 | * parsed from the metadata. We need to find a matching |
| 1762 | * authentication token that has the secret component(s) |
| 1763 | * necessary to decrypt the EFEK in the auth_tok parsed from |
| 1764 | * the metadata. There may be several potential matches, but |
| 1765 | * just one will be sufficient to decrypt to get the FEK. */ |
| 1766 | find_next_matching_auth_tok: |
| 1767 | found_auth_tok = 0; |
| 1768 | list_for_each_entry(auth_tok_list_item, &auth_tok_list, list) { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1769 | candidate_auth_tok = &auth_tok_list_item->auth_tok; |
| 1770 | if (unlikely(ecryptfs_verbosity > 0)) { |
| 1771 | ecryptfs_printk(KERN_DEBUG, |
| 1772 | "Considering cadidate auth tok:\n"); |
| 1773 | ecryptfs_dump_auth_tok(candidate_auth_tok); |
| 1774 | } |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 1775 | rc = ecryptfs_get_auth_tok_sig(&candidate_auth_tok_sig, |
| 1776 | candidate_auth_tok); |
| 1777 | if (rc) { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1778 | printk(KERN_ERR |
| 1779 | "Unrecognized candidate auth tok type: [%d]\n", |
| 1780 | candidate_auth_tok->token_type); |
| 1781 | rc = -EINVAL; |
| 1782 | goto out_wipe_list; |
| 1783 | } |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 1784 | ecryptfs_find_auth_tok_for_sig(&matching_auth_tok, |
| 1785 | crypt_stat->mount_crypt_stat, |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 1786 | candidate_auth_tok_sig); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1787 | if (matching_auth_tok) { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1788 | found_auth_tok = 1; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1789 | goto found_matching_auth_tok; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1790 | } |
| 1791 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1792 | if (!found_auth_tok) { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1793 | ecryptfs_printk(KERN_ERR, "Could not find a usable " |
| 1794 | "authentication token\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1795 | rc = -EIO; |
| 1796 | goto out_wipe_list; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1797 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1798 | found_matching_auth_tok: |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 1799 | if (candidate_auth_tok->token_type == ECRYPTFS_PRIVATE_KEY) { |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1800 | memcpy(&(candidate_auth_tok->token.private_key), |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1801 | &(matching_auth_tok->token.private_key), |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1802 | sizeof(struct ecryptfs_private_key)); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1803 | rc = decrypt_pki_encrypted_session_key(candidate_auth_tok, |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1804 | crypt_stat); |
| 1805 | } else if (candidate_auth_tok->token_type == ECRYPTFS_PASSWORD) { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1806 | memcpy(&(candidate_auth_tok->token.password), |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1807 | &(matching_auth_tok->token.password), |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1808 | sizeof(struct ecryptfs_password)); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1809 | rc = decrypt_passphrase_encrypted_session_key( |
| 1810 | candidate_auth_tok, crypt_stat); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1811 | } |
| 1812 | if (rc) { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1813 | struct ecryptfs_auth_tok_list_item *auth_tok_list_item_tmp; |
| 1814 | |
| 1815 | ecryptfs_printk(KERN_WARNING, "Error decrypting the " |
| 1816 | "session key for authentication token with sig " |
| 1817 | "[%.*s]; rc = [%d]. Removing auth tok " |
| 1818 | "candidate from the list and searching for " |
| 1819 | "the next match.\n", candidate_auth_tok_sig, |
| 1820 | ECRYPTFS_SIG_SIZE_HEX, rc); |
| 1821 | list_for_each_entry_safe(auth_tok_list_item, |
| 1822 | auth_tok_list_item_tmp, |
| 1823 | &auth_tok_list, list) { |
| 1824 | if (candidate_auth_tok |
| 1825 | == &auth_tok_list_item->auth_tok) { |
| 1826 | list_del(&auth_tok_list_item->list); |
| 1827 | kmem_cache_free( |
| 1828 | ecryptfs_auth_tok_list_item_cache, |
| 1829 | auth_tok_list_item); |
| 1830 | goto find_next_matching_auth_tok; |
| 1831 | } |
| 1832 | } |
| 1833 | BUG(); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1834 | } |
| 1835 | rc = ecryptfs_compute_root_iv(crypt_stat); |
| 1836 | if (rc) { |
| 1837 | ecryptfs_printk(KERN_ERR, "Error computing " |
| 1838 | "the root IV\n"); |
| 1839 | goto out_wipe_list; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1840 | } |
| 1841 | rc = ecryptfs_init_crypt_ctx(crypt_stat); |
| 1842 | if (rc) { |
| 1843 | ecryptfs_printk(KERN_ERR, "Error initializing crypto " |
| 1844 | "context for cipher [%s]; rc = [%d]\n", |
| 1845 | crypt_stat->cipher, rc); |
| 1846 | } |
| 1847 | out_wipe_list: |
| 1848 | wipe_auth_tok_list(&auth_tok_list); |
| 1849 | out: |
| 1850 | return rc; |
| 1851 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1852 | |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1853 | static int |
| 1854 | pki_encrypt_session_key(struct ecryptfs_auth_tok *auth_tok, |
| 1855 | struct ecryptfs_crypt_stat *crypt_stat, |
| 1856 | struct ecryptfs_key_record *key_rec) |
| 1857 | { |
| 1858 | struct ecryptfs_msg_ctx *msg_ctx = NULL; |
Tyler Hicks | 624ae52 | 2008-10-15 22:02:51 -0700 | [diff] [blame] | 1859 | char *payload = NULL; |
| 1860 | size_t payload_len; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1861 | struct ecryptfs_message *msg; |
| 1862 | int rc; |
| 1863 | |
| 1864 | rc = write_tag_66_packet(auth_tok->token.private_key.signature, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 1865 | ecryptfs_code_for_cipher_string( |
| 1866 | crypt_stat->cipher, |
| 1867 | crypt_stat->key_size), |
Tyler Hicks | 624ae52 | 2008-10-15 22:02:51 -0700 | [diff] [blame] | 1868 | crypt_stat, &payload, &payload_len); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1869 | if (rc) { |
| 1870 | ecryptfs_printk(KERN_ERR, "Error generating tag 66 packet\n"); |
| 1871 | goto out; |
| 1872 | } |
Tyler Hicks | 624ae52 | 2008-10-15 22:02:51 -0700 | [diff] [blame] | 1873 | rc = ecryptfs_send_message(payload, payload_len, &msg_ctx); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1874 | if (rc) { |
Tyler Hicks | 624ae52 | 2008-10-15 22:02:51 -0700 | [diff] [blame] | 1875 | ecryptfs_printk(KERN_ERR, "Error sending message to " |
| 1876 | "ecryptfsd\n"); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1877 | goto out; |
| 1878 | } |
| 1879 | rc = ecryptfs_wait_for_response(msg_ctx, &msg); |
| 1880 | if (rc) { |
| 1881 | ecryptfs_printk(KERN_ERR, "Failed to receive tag 67 packet " |
| 1882 | "from the user space daemon\n"); |
| 1883 | rc = -EIO; |
| 1884 | goto out; |
| 1885 | } |
| 1886 | rc = parse_tag_67_packet(key_rec, msg); |
| 1887 | if (rc) |
| 1888 | ecryptfs_printk(KERN_ERR, "Error parsing tag 67 packet\n"); |
| 1889 | kfree(msg); |
| 1890 | out: |
Tyler Hicks | 624ae52 | 2008-10-15 22:02:51 -0700 | [diff] [blame] | 1891 | kfree(payload); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1892 | return rc; |
| 1893 | } |
| 1894 | /** |
| 1895 | * write_tag_1_packet - Write an RFC2440-compatible tag 1 (public key) packet |
| 1896 | * @dest: Buffer into which to write the packet |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1897 | * @remaining_bytes: Maximum number of bytes that can be writtn |
| 1898 | * @auth_tok: The authentication token used for generating the tag 1 packet |
| 1899 | * @crypt_stat: The cryptographic context |
| 1900 | * @key_rec: The key record struct for the tag 1 packet |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1901 | * @packet_size: This function will write the number of bytes that end |
| 1902 | * up constituting the packet; set to zero on error |
| 1903 | * |
| 1904 | * Returns zero on success; non-zero on error. |
| 1905 | */ |
| 1906 | static int |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1907 | write_tag_1_packet(char *dest, size_t *remaining_bytes, |
| 1908 | struct ecryptfs_auth_tok *auth_tok, |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1909 | struct ecryptfs_crypt_stat *crypt_stat, |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1910 | struct ecryptfs_key_record *key_rec, size_t *packet_size) |
| 1911 | { |
| 1912 | size_t i; |
| 1913 | size_t encrypted_session_key_valid = 0; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1914 | size_t packet_size_length; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1915 | size_t max_packet_size; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1916 | int rc = 0; |
| 1917 | |
| 1918 | (*packet_size) = 0; |
| 1919 | ecryptfs_from_hex(key_rec->sig, auth_tok->token.private_key.signature, |
| 1920 | ECRYPTFS_SIG_SIZE); |
| 1921 | encrypted_session_key_valid = 0; |
| 1922 | for (i = 0; i < crypt_stat->key_size; i++) |
| 1923 | encrypted_session_key_valid |= |
| 1924 | auth_tok->session_key.encrypted_key[i]; |
| 1925 | if (encrypted_session_key_valid) { |
| 1926 | memcpy(key_rec->enc_key, |
| 1927 | auth_tok->session_key.encrypted_key, |
| 1928 | auth_tok->session_key.encrypted_key_size); |
| 1929 | goto encrypted_session_key_set; |
| 1930 | } |
| 1931 | if (auth_tok->session_key.encrypted_key_size == 0) |
| 1932 | auth_tok->session_key.encrypted_key_size = |
| 1933 | auth_tok->token.private_key.key_size; |
| 1934 | rc = pki_encrypt_session_key(auth_tok, crypt_stat, key_rec); |
| 1935 | if (rc) { |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 1936 | printk(KERN_ERR "Failed to encrypt session key via a key " |
| 1937 | "module; rc = [%d]\n", rc); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1938 | goto out; |
| 1939 | } |
| 1940 | if (ecryptfs_verbosity > 0) { |
| 1941 | ecryptfs_printk(KERN_DEBUG, "Encrypted key:\n"); |
| 1942 | ecryptfs_dump_hex(key_rec->enc_key, key_rec->enc_key_size); |
| 1943 | } |
| 1944 | encrypted_session_key_set: |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1945 | /* This format is inspired by OpenPGP; see RFC 2440 |
| 1946 | * packet tag 1 */ |
| 1947 | max_packet_size = (1 /* Tag 1 identifier */ |
| 1948 | + 3 /* Max Tag 1 packet size */ |
| 1949 | + 1 /* Version */ |
| 1950 | + ECRYPTFS_SIG_SIZE /* Key identifier */ |
| 1951 | + 1 /* Cipher identifier */ |
| 1952 | + key_rec->enc_key_size); /* Encrypted key size */ |
| 1953 | if (max_packet_size > (*remaining_bytes)) { |
| 1954 | printk(KERN_ERR "Packet length larger than maximum allowable; " |
Andrew Morton | 81acbcd | 2007-10-16 01:27:59 -0700 | [diff] [blame] | 1955 | "need up to [%td] bytes, but there are only [%td] " |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1956 | "available\n", max_packet_size, (*remaining_bytes)); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1957 | rc = -EINVAL; |
| 1958 | goto out; |
| 1959 | } |
| 1960 | dest[(*packet_size)++] = ECRYPTFS_TAG_1_PACKET_TYPE; |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 1961 | rc = ecryptfs_write_packet_length(&dest[(*packet_size)], |
| 1962 | (max_packet_size - 4), |
| 1963 | &packet_size_length); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1964 | if (rc) { |
| 1965 | ecryptfs_printk(KERN_ERR, "Error generating tag 1 packet " |
| 1966 | "header; cannot generate packet length\n"); |
| 1967 | goto out; |
| 1968 | } |
| 1969 | (*packet_size) += packet_size_length; |
| 1970 | dest[(*packet_size)++] = 0x03; /* version 3 */ |
| 1971 | memcpy(&dest[(*packet_size)], key_rec->sig, ECRYPTFS_SIG_SIZE); |
| 1972 | (*packet_size) += ECRYPTFS_SIG_SIZE; |
| 1973 | dest[(*packet_size)++] = RFC2440_CIPHER_RSA; |
| 1974 | memcpy(&dest[(*packet_size)], key_rec->enc_key, |
| 1975 | key_rec->enc_key_size); |
| 1976 | (*packet_size) += key_rec->enc_key_size; |
| 1977 | out: |
| 1978 | if (rc) |
| 1979 | (*packet_size) = 0; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1980 | else |
| 1981 | (*remaining_bytes) -= (*packet_size); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1982 | return rc; |
| 1983 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1984 | |
| 1985 | /** |
| 1986 | * write_tag_11_packet |
| 1987 | * @dest: Target into which Tag 11 packet is to be written |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1988 | * @remaining_bytes: Maximum packet length |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1989 | * @contents: Byte array of contents to copy in |
| 1990 | * @contents_length: Number of bytes in contents |
| 1991 | * @packet_length: Length of the Tag 11 packet written; zero on error |
| 1992 | * |
| 1993 | * Returns zero on success; non-zero on error. |
| 1994 | */ |
| 1995 | static int |
Andrew Morton | 81acbcd | 2007-10-16 01:27:59 -0700 | [diff] [blame] | 1996 | write_tag_11_packet(char *dest, size_t *remaining_bytes, char *contents, |
Michael Halcrow | 146a460 | 2007-10-16 01:27:58 -0700 | [diff] [blame] | 1997 | size_t contents_length, size_t *packet_length) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1998 | { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1999 | size_t packet_size_length; |
Michael Halcrow | 146a460 | 2007-10-16 01:27:58 -0700 | [diff] [blame] | 2000 | size_t max_packet_size; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2001 | int rc = 0; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2002 | |
| 2003 | (*packet_length) = 0; |
Michael Halcrow | 146a460 | 2007-10-16 01:27:58 -0700 | [diff] [blame] | 2004 | /* This format is inspired by OpenPGP; see RFC 2440 |
| 2005 | * packet tag 11 */ |
| 2006 | max_packet_size = (1 /* Tag 11 identifier */ |
| 2007 | + 3 /* Max Tag 11 packet size */ |
| 2008 | + 1 /* Binary format specifier */ |
| 2009 | + 1 /* Filename length */ |
| 2010 | + 8 /* Filename ("_CONSOLE") */ |
| 2011 | + 4 /* Modification date */ |
| 2012 | + contents_length); /* Literal data */ |
| 2013 | if (max_packet_size > (*remaining_bytes)) { |
| 2014 | printk(KERN_ERR "Packet length larger than maximum allowable; " |
Andrew Morton | 81acbcd | 2007-10-16 01:27:59 -0700 | [diff] [blame] | 2015 | "need up to [%td] bytes, but there are only [%td] " |
Michael Halcrow | 146a460 | 2007-10-16 01:27:58 -0700 | [diff] [blame] | 2016 | "available\n", max_packet_size, (*remaining_bytes)); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2017 | rc = -EINVAL; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2018 | goto out; |
| 2019 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2020 | dest[(*packet_length)++] = ECRYPTFS_TAG_11_PACKET_TYPE; |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 2021 | rc = ecryptfs_write_packet_length(&dest[(*packet_length)], |
| 2022 | (max_packet_size - 4), |
| 2023 | &packet_size_length); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2024 | if (rc) { |
Michael Halcrow | 146a460 | 2007-10-16 01:27:58 -0700 | [diff] [blame] | 2025 | printk(KERN_ERR "Error generating tag 11 packet header; cannot " |
| 2026 | "generate packet length. rc = [%d]\n", rc); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2027 | goto out; |
| 2028 | } |
| 2029 | (*packet_length) += packet_size_length; |
Michael Halcrow | 146a460 | 2007-10-16 01:27:58 -0700 | [diff] [blame] | 2030 | dest[(*packet_length)++] = 0x62; /* binary data format specifier */ |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2031 | dest[(*packet_length)++] = 8; |
| 2032 | memcpy(&dest[(*packet_length)], "_CONSOLE", 8); |
| 2033 | (*packet_length) += 8; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2034 | memset(&dest[(*packet_length)], 0x00, 4); |
| 2035 | (*packet_length) += 4; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2036 | memcpy(&dest[(*packet_length)], contents, contents_length); |
| 2037 | (*packet_length) += contents_length; |
| 2038 | out: |
| 2039 | if (rc) |
| 2040 | (*packet_length) = 0; |
Michael Halcrow | 146a460 | 2007-10-16 01:27:58 -0700 | [diff] [blame] | 2041 | else |
| 2042 | (*remaining_bytes) -= (*packet_length); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2043 | return rc; |
| 2044 | } |
| 2045 | |
| 2046 | /** |
| 2047 | * write_tag_3_packet |
| 2048 | * @dest: Buffer into which to write the packet |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 2049 | * @remaining_bytes: Maximum number of bytes that can be written |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2050 | * @auth_tok: Authentication token |
| 2051 | * @crypt_stat: The cryptographic context |
| 2052 | * @key_rec: encrypted key |
| 2053 | * @packet_size: This function will write the number of bytes that end |
| 2054 | * up constituting the packet; set to zero on error |
| 2055 | * |
| 2056 | * Returns zero on success; non-zero on error. |
| 2057 | */ |
| 2058 | static int |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2059 | write_tag_3_packet(char *dest, size_t *remaining_bytes, |
| 2060 | struct ecryptfs_auth_tok *auth_tok, |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2061 | struct ecryptfs_crypt_stat *crypt_stat, |
| 2062 | struct ecryptfs_key_record *key_rec, size_t *packet_size) |
| 2063 | { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2064 | size_t i; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2065 | size_t encrypted_session_key_valid = 0; |
| 2066 | char session_key_encryption_key[ECRYPTFS_MAX_KEY_BYTES]; |
Michael Halcrow | ac97b9f | 2008-11-19 15:36:28 -0800 | [diff] [blame] | 2067 | struct scatterlist dst_sg[2]; |
| 2068 | struct scatterlist src_sg[2]; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2069 | struct mutex *tfm_mutex = NULL; |
Trevor Highland | 19e66a6 | 2008-02-06 01:38:36 -0800 | [diff] [blame] | 2070 | u8 cipher_code; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2071 | size_t packet_size_length; |
| 2072 | size_t max_packet_size; |
| 2073 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat = |
| 2074 | crypt_stat->mount_crypt_stat; |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 2075 | struct blkcipher_desc desc = { |
| 2076 | .tfm = NULL, |
| 2077 | .flags = CRYPTO_TFM_REQ_MAY_SLEEP |
| 2078 | }; |
| 2079 | int rc = 0; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2080 | |
| 2081 | (*packet_size) = 0; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2082 | ecryptfs_from_hex(key_rec->sig, auth_tok->token.password.signature, |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2083 | ECRYPTFS_SIG_SIZE); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2084 | rc = ecryptfs_get_tfm_and_mutex_for_cipher_name(&desc.tfm, &tfm_mutex, |
| 2085 | crypt_stat->cipher); |
| 2086 | if (unlikely(rc)) { |
| 2087 | printk(KERN_ERR "Internal error whilst attempting to get " |
| 2088 | "tfm and mutex for cipher name [%s]; rc = [%d]\n", |
| 2089 | crypt_stat->cipher, rc); |
| 2090 | goto out; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2091 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2092 | if (mount_crypt_stat->global_default_cipher_key_size == 0) { |
| 2093 | struct blkcipher_alg *alg = crypto_blkcipher_alg(desc.tfm); |
| 2094 | |
| 2095 | printk(KERN_WARNING "No key size specified at mount; " |
| 2096 | "defaulting to [%d]\n", alg->max_keysize); |
| 2097 | mount_crypt_stat->global_default_cipher_key_size = |
| 2098 | alg->max_keysize; |
| 2099 | } |
| 2100 | if (crypt_stat->key_size == 0) |
| 2101 | crypt_stat->key_size = |
| 2102 | mount_crypt_stat->global_default_cipher_key_size; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2103 | if (auth_tok->session_key.encrypted_key_size == 0) |
| 2104 | auth_tok->session_key.encrypted_key_size = |
| 2105 | crypt_stat->key_size; |
| 2106 | if (crypt_stat->key_size == 24 |
| 2107 | && strcmp("aes", crypt_stat->cipher) == 0) { |
| 2108 | memset((crypt_stat->key + 24), 0, 8); |
| 2109 | auth_tok->session_key.encrypted_key_size = 32; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2110 | } else |
| 2111 | auth_tok->session_key.encrypted_key_size = crypt_stat->key_size; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2112 | key_rec->enc_key_size = |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2113 | auth_tok->session_key.encrypted_key_size; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2114 | encrypted_session_key_valid = 0; |
| 2115 | for (i = 0; i < auth_tok->session_key.encrypted_key_size; i++) |
| 2116 | encrypted_session_key_valid |= |
| 2117 | auth_tok->session_key.encrypted_key[i]; |
| 2118 | if (encrypted_session_key_valid) { |
| 2119 | ecryptfs_printk(KERN_DEBUG, "encrypted_session_key_valid != 0; " |
| 2120 | "using auth_tok->session_key.encrypted_key, " |
| 2121 | "where key_rec->enc_key_size = [%d]\n", |
| 2122 | key_rec->enc_key_size); |
| 2123 | memcpy(key_rec->enc_key, |
| 2124 | auth_tok->session_key.encrypted_key, |
| 2125 | key_rec->enc_key_size); |
| 2126 | goto encrypted_session_key_set; |
| 2127 | } |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2128 | if (auth_tok->token.password.flags & |
| 2129 | ECRYPTFS_SESSION_KEY_ENCRYPTION_KEY_SET) { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2130 | ecryptfs_printk(KERN_DEBUG, "Using previously generated " |
| 2131 | "session key encryption key of size [%d]\n", |
| 2132 | auth_tok->token.password. |
| 2133 | session_key_encryption_key_bytes); |
| 2134 | memcpy(session_key_encryption_key, |
| 2135 | auth_tok->token.password.session_key_encryption_key, |
| 2136 | crypt_stat->key_size); |
| 2137 | ecryptfs_printk(KERN_DEBUG, |
| 2138 | "Cached session key " "encryption key: \n"); |
| 2139 | if (ecryptfs_verbosity > 0) |
| 2140 | ecryptfs_dump_hex(session_key_encryption_key, 16); |
| 2141 | } |
| 2142 | if (unlikely(ecryptfs_verbosity > 0)) { |
| 2143 | ecryptfs_printk(KERN_DEBUG, "Session key encryption key:\n"); |
| 2144 | ecryptfs_dump_hex(session_key_encryption_key, 16); |
| 2145 | } |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 2146 | rc = virt_to_scatterlist(crypt_stat->key, key_rec->enc_key_size, |
Michael Halcrow | ac97b9f | 2008-11-19 15:36:28 -0800 | [diff] [blame] | 2147 | src_sg, 2); |
| 2148 | if (rc < 1 || rc > 2) { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2149 | ecryptfs_printk(KERN_ERR, "Error generating scatterlist " |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2150 | "for crypt_stat session key; expected rc = 1; " |
| 2151 | "got rc = [%d]. key_rec->enc_key_size = [%d]\n", |
| 2152 | rc, key_rec->enc_key_size); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2153 | rc = -ENOMEM; |
| 2154 | goto out; |
| 2155 | } |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 2156 | rc = virt_to_scatterlist(key_rec->enc_key, key_rec->enc_key_size, |
Michael Halcrow | ac97b9f | 2008-11-19 15:36:28 -0800 | [diff] [blame] | 2157 | dst_sg, 2); |
| 2158 | if (rc < 1 || rc > 2) { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2159 | ecryptfs_printk(KERN_ERR, "Error generating scatterlist " |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2160 | "for crypt_stat encrypted session key; " |
| 2161 | "expected rc = 1; got rc = [%d]. " |
| 2162 | "key_rec->enc_key_size = [%d]\n", rc, |
| 2163 | key_rec->enc_key_size); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2164 | rc = -ENOMEM; |
| 2165 | goto out; |
| 2166 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2167 | mutex_lock(tfm_mutex); |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 2168 | rc = crypto_blkcipher_setkey(desc.tfm, session_key_encryption_key, |
| 2169 | crypt_stat->key_size); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2170 | if (rc < 0) { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2171 | mutex_unlock(tfm_mutex); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2172 | ecryptfs_printk(KERN_ERR, "Error setting key for crypto " |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 2173 | "context; rc = [%d]\n", rc); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2174 | goto out; |
| 2175 | } |
| 2176 | rc = 0; |
| 2177 | ecryptfs_printk(KERN_DEBUG, "Encrypting [%d] bytes of the key\n", |
| 2178 | crypt_stat->key_size); |
Michael Halcrow | ac97b9f | 2008-11-19 15:36:28 -0800 | [diff] [blame] | 2179 | rc = crypto_blkcipher_encrypt(&desc, dst_sg, src_sg, |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 2180 | (*key_rec).enc_key_size); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2181 | mutex_unlock(tfm_mutex); |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 2182 | if (rc) { |
| 2183 | printk(KERN_ERR "Error encrypting; rc = [%d]\n", rc); |
| 2184 | goto out; |
| 2185 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2186 | ecryptfs_printk(KERN_DEBUG, "This should be the encrypted key:\n"); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2187 | if (ecryptfs_verbosity > 0) { |
| 2188 | ecryptfs_printk(KERN_DEBUG, "EFEK of size [%d]:\n", |
| 2189 | key_rec->enc_key_size); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2190 | ecryptfs_dump_hex(key_rec->enc_key, |
| 2191 | key_rec->enc_key_size); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2192 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2193 | encrypted_session_key_set: |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2194 | /* This format is inspired by OpenPGP; see RFC 2440 |
| 2195 | * packet tag 3 */ |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2196 | max_packet_size = (1 /* Tag 3 identifier */ |
| 2197 | + 3 /* Max Tag 3 packet size */ |
| 2198 | + 1 /* Version */ |
| 2199 | + 1 /* Cipher code */ |
| 2200 | + 1 /* S2K specifier */ |
| 2201 | + 1 /* Hash identifier */ |
| 2202 | + ECRYPTFS_SALT_SIZE /* Salt */ |
| 2203 | + 1 /* Hash iterations */ |
| 2204 | + key_rec->enc_key_size); /* Encrypted key size */ |
| 2205 | if (max_packet_size > (*remaining_bytes)) { |
Andrew Morton | 81acbcd | 2007-10-16 01:27:59 -0700 | [diff] [blame] | 2206 | printk(KERN_ERR "Packet too large; need up to [%td] bytes, but " |
| 2207 | "there are only [%td] available\n", max_packet_size, |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2208 | (*remaining_bytes)); |
| 2209 | rc = -EINVAL; |
| 2210 | goto out; |
| 2211 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2212 | dest[(*packet_size)++] = ECRYPTFS_TAG_3_PACKET_TYPE; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2213 | /* Chop off the Tag 3 identifier(1) and Tag 3 packet size(3) |
| 2214 | * to get the number of octets in the actual Tag 3 packet */ |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 2215 | rc = ecryptfs_write_packet_length(&dest[(*packet_size)], |
| 2216 | (max_packet_size - 4), |
| 2217 | &packet_size_length); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2218 | if (rc) { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2219 | printk(KERN_ERR "Error generating tag 3 packet header; cannot " |
| 2220 | "generate packet length. rc = [%d]\n", rc); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2221 | goto out; |
| 2222 | } |
| 2223 | (*packet_size) += packet_size_length; |
| 2224 | dest[(*packet_size)++] = 0x04; /* version 4 */ |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2225 | /* TODO: Break from RFC2440 so that arbitrary ciphers can be |
| 2226 | * specified with strings */ |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 2227 | cipher_code = ecryptfs_code_for_cipher_string(crypt_stat->cipher, |
| 2228 | crypt_stat->key_size); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2229 | if (cipher_code == 0) { |
| 2230 | ecryptfs_printk(KERN_WARNING, "Unable to generate code for " |
| 2231 | "cipher [%s]\n", crypt_stat->cipher); |
| 2232 | rc = -EINVAL; |
| 2233 | goto out; |
| 2234 | } |
| 2235 | dest[(*packet_size)++] = cipher_code; |
| 2236 | dest[(*packet_size)++] = 0x03; /* S2K */ |
| 2237 | dest[(*packet_size)++] = 0x01; /* MD5 (TODO: parameterize) */ |
| 2238 | memcpy(&dest[(*packet_size)], auth_tok->token.password.salt, |
| 2239 | ECRYPTFS_SALT_SIZE); |
| 2240 | (*packet_size) += ECRYPTFS_SALT_SIZE; /* salt */ |
| 2241 | dest[(*packet_size)++] = 0x60; /* hash iterations (65536) */ |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2242 | memcpy(&dest[(*packet_size)], key_rec->enc_key, |
| 2243 | key_rec->enc_key_size); |
| 2244 | (*packet_size) += key_rec->enc_key_size; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2245 | out: |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2246 | if (rc) |
| 2247 | (*packet_size) = 0; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2248 | else |
| 2249 | (*remaining_bytes) -= (*packet_size); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2250 | return rc; |
| 2251 | } |
| 2252 | |
Michael Halcrow | eb95e7f | 2007-02-16 01:28:40 -0800 | [diff] [blame] | 2253 | struct kmem_cache *ecryptfs_key_record_cache; |
| 2254 | |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2255 | /** |
| 2256 | * ecryptfs_generate_key_packet_set |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 2257 | * @dest_base: Virtual address from which to write the key record set |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2258 | * @crypt_stat: The cryptographic context from which the |
| 2259 | * authentication tokens will be retrieved |
| 2260 | * @ecryptfs_dentry: The dentry, used to retrieve the mount crypt stat |
| 2261 | * for the global parameters |
| 2262 | * @len: The amount written |
| 2263 | * @max: The maximum amount of data allowed to be written |
| 2264 | * |
| 2265 | * Generates a key packet set and writes it to the virtual address |
| 2266 | * passed in. |
| 2267 | * |
| 2268 | * Returns zero on success; non-zero on error. |
| 2269 | */ |
| 2270 | int |
| 2271 | ecryptfs_generate_key_packet_set(char *dest_base, |
| 2272 | struct ecryptfs_crypt_stat *crypt_stat, |
| 2273 | struct dentry *ecryptfs_dentry, size_t *len, |
| 2274 | size_t max) |
| 2275 | { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2276 | struct ecryptfs_auth_tok *auth_tok; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2277 | struct ecryptfs_global_auth_tok *global_auth_tok; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2278 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat = |
| 2279 | &ecryptfs_superblock_to_private( |
| 2280 | ecryptfs_dentry->d_sb)->mount_crypt_stat; |
| 2281 | size_t written; |
Michael Halcrow | eb95e7f | 2007-02-16 01:28:40 -0800 | [diff] [blame] | 2282 | struct ecryptfs_key_record *key_rec; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2283 | struct ecryptfs_key_sig *key_sig; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2284 | int rc = 0; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2285 | |
| 2286 | (*len) = 0; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2287 | mutex_lock(&crypt_stat->keysig_list_mutex); |
Michael Halcrow | eb95e7f | 2007-02-16 01:28:40 -0800 | [diff] [blame] | 2288 | key_rec = kmem_cache_alloc(ecryptfs_key_record_cache, GFP_KERNEL); |
| 2289 | if (!key_rec) { |
| 2290 | rc = -ENOMEM; |
| 2291 | goto out; |
| 2292 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2293 | list_for_each_entry(key_sig, &crypt_stat->keysig_list, |
| 2294 | crypt_stat_list) { |
| 2295 | memset(key_rec, 0, sizeof(*key_rec)); |
| 2296 | rc = ecryptfs_find_global_auth_tok_for_sig(&global_auth_tok, |
| 2297 | mount_crypt_stat, |
| 2298 | key_sig->keysig); |
| 2299 | if (rc) { |
| 2300 | printk(KERN_ERR "Error attempting to get the global " |
| 2301 | "auth_tok; rc = [%d]\n", rc); |
| 2302 | goto out_free; |
| 2303 | } |
| 2304 | if (global_auth_tok->flags & ECRYPTFS_AUTH_TOK_INVALID) { |
| 2305 | printk(KERN_WARNING |
| 2306 | "Skipping invalid auth tok with sig = [%s]\n", |
| 2307 | global_auth_tok->sig); |
| 2308 | continue; |
| 2309 | } |
| 2310 | auth_tok = global_auth_tok->global_auth_tok; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2311 | if (auth_tok->token_type == ECRYPTFS_PASSWORD) { |
| 2312 | rc = write_tag_3_packet((dest_base + (*len)), |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2313 | &max, auth_tok, |
Michael Halcrow | eb95e7f | 2007-02-16 01:28:40 -0800 | [diff] [blame] | 2314 | crypt_stat, key_rec, |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2315 | &written); |
| 2316 | if (rc) { |
| 2317 | ecryptfs_printk(KERN_WARNING, "Error " |
| 2318 | "writing tag 3 packet\n"); |
Michael Halcrow | eb95e7f | 2007-02-16 01:28:40 -0800 | [diff] [blame] | 2319 | goto out_free; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2320 | } |
| 2321 | (*len) += written; |
| 2322 | /* Write auth tok signature packet */ |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2323 | rc = write_tag_11_packet((dest_base + (*len)), &max, |
| 2324 | key_rec->sig, |
| 2325 | ECRYPTFS_SIG_SIZE, &written); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2326 | if (rc) { |
| 2327 | ecryptfs_printk(KERN_ERR, "Error writing " |
| 2328 | "auth tok signature packet\n"); |
Michael Halcrow | eb95e7f | 2007-02-16 01:28:40 -0800 | [diff] [blame] | 2329 | goto out_free; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2330 | } |
| 2331 | (*len) += written; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2332 | } else if (auth_tok->token_type == ECRYPTFS_PRIVATE_KEY) { |
| 2333 | rc = write_tag_1_packet(dest_base + (*len), |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2334 | &max, auth_tok, |
| 2335 | crypt_stat, key_rec, &written); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2336 | if (rc) { |
| 2337 | ecryptfs_printk(KERN_WARNING, "Error " |
| 2338 | "writing tag 1 packet\n"); |
Michael Halcrow | eb95e7f | 2007-02-16 01:28:40 -0800 | [diff] [blame] | 2339 | goto out_free; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2340 | } |
| 2341 | (*len) += written; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2342 | } else { |
| 2343 | ecryptfs_printk(KERN_WARNING, "Unsupported " |
| 2344 | "authentication token type\n"); |
| 2345 | rc = -EINVAL; |
Michael Halcrow | eb95e7f | 2007-02-16 01:28:40 -0800 | [diff] [blame] | 2346 | goto out_free; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2347 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2348 | } |
| 2349 | if (likely(max > 0)) { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2350 | dest_base[(*len)] = 0x00; |
| 2351 | } else { |
| 2352 | ecryptfs_printk(KERN_ERR, "Error writing boundary byte\n"); |
| 2353 | rc = -EIO; |
| 2354 | } |
Michael Halcrow | eb95e7f | 2007-02-16 01:28:40 -0800 | [diff] [blame] | 2355 | out_free: |
| 2356 | kmem_cache_free(ecryptfs_key_record_cache, key_rec); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2357 | out: |
| 2358 | if (rc) |
| 2359 | (*len) = 0; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2360 | mutex_unlock(&crypt_stat->keysig_list_mutex); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2361 | return rc; |
| 2362 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2363 | |
| 2364 | struct kmem_cache *ecryptfs_key_sig_cache; |
| 2365 | |
| 2366 | int ecryptfs_add_keysig(struct ecryptfs_crypt_stat *crypt_stat, char *sig) |
| 2367 | { |
| 2368 | struct ecryptfs_key_sig *new_key_sig; |
| 2369 | int rc = 0; |
| 2370 | |
| 2371 | new_key_sig = kmem_cache_alloc(ecryptfs_key_sig_cache, GFP_KERNEL); |
| 2372 | if (!new_key_sig) { |
| 2373 | rc = -ENOMEM; |
| 2374 | printk(KERN_ERR |
| 2375 | "Error allocating from ecryptfs_key_sig_cache\n"); |
| 2376 | goto out; |
| 2377 | } |
| 2378 | memcpy(new_key_sig->keysig, sig, ECRYPTFS_SIG_SIZE_HEX); |
| 2379 | mutex_lock(&crypt_stat->keysig_list_mutex); |
| 2380 | list_add(&new_key_sig->crypt_stat_list, &crypt_stat->keysig_list); |
| 2381 | mutex_unlock(&crypt_stat->keysig_list_mutex); |
| 2382 | out: |
| 2383 | return rc; |
| 2384 | } |
| 2385 | |
| 2386 | struct kmem_cache *ecryptfs_global_auth_tok_cache; |
| 2387 | |
| 2388 | int |
| 2389 | ecryptfs_add_global_auth_tok(struct ecryptfs_mount_crypt_stat *mount_crypt_stat, |
Tyler Hicks | 84814d6 | 2009-03-13 13:51:59 -0700 | [diff] [blame] | 2390 | char *sig, u32 global_auth_tok_flags) |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2391 | { |
| 2392 | struct ecryptfs_global_auth_tok *new_auth_tok; |
| 2393 | int rc = 0; |
| 2394 | |
Eric Sandeen | 459e216 | 2007-12-17 16:19:52 -0800 | [diff] [blame] | 2395 | new_auth_tok = kmem_cache_zalloc(ecryptfs_global_auth_tok_cache, |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2396 | GFP_KERNEL); |
| 2397 | if (!new_auth_tok) { |
| 2398 | rc = -ENOMEM; |
| 2399 | printk(KERN_ERR "Error allocating from " |
| 2400 | "ecryptfs_global_auth_tok_cache\n"); |
| 2401 | goto out; |
| 2402 | } |
| 2403 | memcpy(new_auth_tok->sig, sig, ECRYPTFS_SIG_SIZE_HEX); |
Tyler Hicks | 84814d6 | 2009-03-13 13:51:59 -0700 | [diff] [blame] | 2404 | new_auth_tok->flags = global_auth_tok_flags; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2405 | new_auth_tok->sig[ECRYPTFS_SIG_SIZE_HEX] = '\0'; |
| 2406 | mutex_lock(&mount_crypt_stat->global_auth_tok_list_mutex); |
| 2407 | list_add(&new_auth_tok->mount_crypt_stat_list, |
| 2408 | &mount_crypt_stat->global_auth_tok_list); |
| 2409 | mount_crypt_stat->num_global_auth_toks++; |
| 2410 | mutex_unlock(&mount_crypt_stat->global_auth_tok_list_mutex); |
| 2411 | out: |
| 2412 | return rc; |
| 2413 | } |
| 2414 | |