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: |
| 743 | memset(s->block_aligned_filename, 0, s->block_aligned_filename_size); |
| 744 | kfree(s->block_aligned_filename); |
| 745 | out_unlock: |
| 746 | mutex_unlock(s->tfm_mutex); |
| 747 | out: |
| 748 | kfree(s); |
| 749 | return rc; |
| 750 | } |
| 751 | |
| 752 | struct ecryptfs_parse_tag_70_packet_silly_stack { |
| 753 | u8 cipher_code; |
| 754 | size_t max_packet_size; |
| 755 | size_t packet_size_len; |
| 756 | size_t parsed_tag_70_packet_size; |
| 757 | size_t block_aligned_filename_size; |
| 758 | size_t block_size; |
| 759 | size_t i; |
| 760 | struct mutex *tfm_mutex; |
| 761 | char *decrypted_filename; |
| 762 | struct ecryptfs_auth_tok *auth_tok; |
| 763 | struct scatterlist src_sg; |
| 764 | struct scatterlist dst_sg; |
| 765 | struct blkcipher_desc desc; |
| 766 | char fnek_sig_hex[ECRYPTFS_SIG_SIZE_HEX + 1]; |
| 767 | char iv[ECRYPTFS_MAX_IV_BYTES]; |
| 768 | char cipher_string[ECRYPTFS_MAX_CIPHER_NAME_SIZE]; |
| 769 | }; |
| 770 | |
| 771 | /** |
| 772 | * parse_tag_70_packet - Parse and process FNEK-encrypted passphrase packet |
| 773 | * @filename: This function kmalloc's the memory for the filename |
Michael Halcrow | 7d8bc2b | 2009-01-06 14:42:04 -0800 | [diff] [blame] | 774 | * @filename_size: This function sets this to the amount of memory |
| 775 | * kmalloc'd for the filename |
| 776 | * @packet_size: This function sets this to the the number of octets |
| 777 | * in the packet parsed |
| 778 | * @mount_crypt_stat: The mount-wide cryptographic context |
| 779 | * @data: The memory location containing the start of the tag 70 |
| 780 | * packet |
| 781 | * @max_packet_size: The maximum legal size of the packet to be parsed |
| 782 | * from @data |
| 783 | * |
| 784 | * Returns zero on success; non-zero otherwise |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 785 | */ |
| 786 | int |
| 787 | ecryptfs_parse_tag_70_packet(char **filename, size_t *filename_size, |
| 788 | size_t *packet_size, |
| 789 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat, |
| 790 | char *data, size_t max_packet_size) |
| 791 | { |
| 792 | struct ecryptfs_parse_tag_70_packet_silly_stack *s; |
| 793 | int rc = 0; |
| 794 | |
| 795 | (*packet_size) = 0; |
| 796 | (*filename_size) = 0; |
| 797 | (*filename) = NULL; |
| 798 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
| 799 | if (!s) { |
| 800 | printk(KERN_ERR "%s: Out of memory whilst trying to kmalloc " |
Michael Halcrow | a8f1286 | 2009-01-06 14:42:03 -0800 | [diff] [blame] | 801 | "[%zd] bytes of kernel memory\n", __func__, sizeof(*s)); |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 802 | goto out; |
| 803 | } |
| 804 | s->desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP; |
| 805 | if (max_packet_size < (1 + 1 + ECRYPTFS_SIG_SIZE + 1 + 1)) { |
Michael Halcrow | df261c5 | 2009-01-06 14:42:02 -0800 | [diff] [blame] | 806 | printk(KERN_WARNING "%s: max_packet_size is [%zd]; it must be " |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 807 | "at least [%d]\n", __func__, max_packet_size, |
| 808 | (1 + 1 + ECRYPTFS_SIG_SIZE + 1 + 1)); |
| 809 | rc = -EINVAL; |
| 810 | goto out; |
| 811 | } |
| 812 | /* Octet 0: Tag 70 identifier |
| 813 | * Octets 1-N1: Tag 70 packet size (includes cipher identifier |
| 814 | * and block-aligned encrypted filename size) |
| 815 | * Octets N1-N2: FNEK sig (ECRYPTFS_SIG_SIZE) |
| 816 | * Octet N2-N3: Cipher identifier (1 octet) |
| 817 | * Octets N3-N4: Block-aligned encrypted filename |
| 818 | * - Consists of a minimum number of random numbers, a \0 |
| 819 | * separator, and then the filename */ |
| 820 | if (data[(*packet_size)++] != ECRYPTFS_TAG_70_PACKET_TYPE) { |
| 821 | printk(KERN_WARNING "%s: Invalid packet tag [0x%.2x]; must be " |
| 822 | "tag [0x%.2x]\n", __func__, |
| 823 | data[((*packet_size) - 1)], ECRYPTFS_TAG_70_PACKET_TYPE); |
| 824 | rc = -EINVAL; |
| 825 | goto out; |
| 826 | } |
| 827 | rc = ecryptfs_parse_packet_length(&data[(*packet_size)], |
| 828 | &s->parsed_tag_70_packet_size, |
| 829 | &s->packet_size_len); |
| 830 | if (rc) { |
| 831 | printk(KERN_WARNING "%s: Error parsing packet length; " |
| 832 | "rc = [%d]\n", __func__, rc); |
| 833 | goto out; |
| 834 | } |
| 835 | s->block_aligned_filename_size = (s->parsed_tag_70_packet_size |
| 836 | - ECRYPTFS_SIG_SIZE - 1); |
| 837 | if ((1 + s->packet_size_len + s->parsed_tag_70_packet_size) |
| 838 | > max_packet_size) { |
Michael Halcrow | a8f1286 | 2009-01-06 14:42:03 -0800 | [diff] [blame] | 839 | printk(KERN_WARNING "%s: max_packet_size is [%zd]; real packet " |
| 840 | "size is [%zd]\n", __func__, max_packet_size, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 841 | (1 + s->packet_size_len + 1 |
| 842 | + s->block_aligned_filename_size)); |
| 843 | rc = -EINVAL; |
| 844 | goto out; |
| 845 | } |
| 846 | (*packet_size) += s->packet_size_len; |
| 847 | ecryptfs_to_hex(s->fnek_sig_hex, &data[(*packet_size)], |
| 848 | ECRYPTFS_SIG_SIZE); |
| 849 | s->fnek_sig_hex[ECRYPTFS_SIG_SIZE_HEX] = '\0'; |
| 850 | (*packet_size) += ECRYPTFS_SIG_SIZE; |
| 851 | s->cipher_code = data[(*packet_size)++]; |
| 852 | rc = ecryptfs_cipher_code_to_string(s->cipher_string, s->cipher_code); |
| 853 | if (rc) { |
| 854 | printk(KERN_WARNING "%s: Cipher code [%d] is invalid\n", |
| 855 | __func__, s->cipher_code); |
| 856 | goto out; |
| 857 | } |
| 858 | rc = ecryptfs_get_tfm_and_mutex_for_cipher_name(&s->desc.tfm, |
| 859 | &s->tfm_mutex, |
| 860 | s->cipher_string); |
| 861 | if (unlikely(rc)) { |
| 862 | printk(KERN_ERR "Internal error whilst attempting to get " |
| 863 | "tfm and mutex for cipher name [%s]; rc = [%d]\n", |
| 864 | s->cipher_string, rc); |
| 865 | goto out; |
| 866 | } |
| 867 | mutex_lock(s->tfm_mutex); |
| 868 | rc = virt_to_scatterlist(&data[(*packet_size)], |
| 869 | s->block_aligned_filename_size, &s->src_sg, 1); |
| 870 | if (rc != 1) { |
| 871 | printk(KERN_ERR "%s: Internal error whilst attempting to " |
| 872 | "convert encrypted filename memory to scatterlist; " |
| 873 | "expected rc = 1; got rc = [%d]. " |
Michael Halcrow | a8f1286 | 2009-01-06 14:42:03 -0800 | [diff] [blame] | 874 | "block_aligned_filename_size = [%zd]\n", __func__, rc, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 875 | s->block_aligned_filename_size); |
| 876 | goto out_unlock; |
| 877 | } |
| 878 | (*packet_size) += s->block_aligned_filename_size; |
| 879 | s->decrypted_filename = kmalloc(s->block_aligned_filename_size, |
| 880 | GFP_KERNEL); |
| 881 | if (!s->decrypted_filename) { |
| 882 | printk(KERN_ERR "%s: Out of memory whilst attempting to " |
Michael Halcrow | a8f1286 | 2009-01-06 14:42:03 -0800 | [diff] [blame] | 883 | "kmalloc [%zd] bytes\n", __func__, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 884 | s->block_aligned_filename_size); |
| 885 | rc = -ENOMEM; |
| 886 | goto out_unlock; |
| 887 | } |
| 888 | rc = virt_to_scatterlist(s->decrypted_filename, |
| 889 | s->block_aligned_filename_size, &s->dst_sg, 1); |
| 890 | if (rc != 1) { |
| 891 | printk(KERN_ERR "%s: Internal error whilst attempting to " |
| 892 | "convert decrypted filename memory to scatterlist; " |
| 893 | "expected rc = 1; got rc = [%d]. " |
Michael Halcrow | a8f1286 | 2009-01-06 14:42:03 -0800 | [diff] [blame] | 894 | "block_aligned_filename_size = [%zd]\n", __func__, rc, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 895 | s->block_aligned_filename_size); |
| 896 | goto out_free_unlock; |
| 897 | } |
| 898 | /* The characters in the first block effectively do the job of |
| 899 | * the IV here, so we just use 0's for the IV. Note the |
| 900 | * constraint that ECRYPTFS_FILENAME_MIN_RANDOM_PREPEND_BYTES |
| 901 | * >= ECRYPTFS_MAX_IV_BYTES. */ |
| 902 | memset(s->iv, 0, ECRYPTFS_MAX_IV_BYTES); |
| 903 | s->desc.info = s->iv; |
| 904 | rc = ecryptfs_find_auth_tok_for_sig(&s->auth_tok, mount_crypt_stat, |
| 905 | s->fnek_sig_hex); |
| 906 | if (rc) { |
| 907 | printk(KERN_ERR "%s: Error attempting to find auth tok for " |
| 908 | "fnek sig [%s]; rc = [%d]\n", __func__, s->fnek_sig_hex, |
| 909 | rc); |
| 910 | goto out_free_unlock; |
| 911 | } |
| 912 | /* TODO: Support other key modules than passphrase for |
| 913 | * filename encryption */ |
| 914 | BUG_ON(s->auth_tok->token_type != ECRYPTFS_PASSWORD); |
| 915 | rc = crypto_blkcipher_setkey( |
| 916 | s->desc.tfm, |
| 917 | s->auth_tok->token.password.session_key_encryption_key, |
| 918 | mount_crypt_stat->global_default_fn_cipher_key_bytes); |
| 919 | if (rc < 0) { |
| 920 | printk(KERN_ERR "%s: Error setting key for crypto context; " |
| 921 | "rc = [%d]. s->auth_tok->token.password.session_key_" |
| 922 | "encryption_key = [0x%p]; mount_crypt_stat->" |
Michael Halcrow | df261c5 | 2009-01-06 14:42:02 -0800 | [diff] [blame] | 923 | "global_default_fn_cipher_key_bytes = [%zd]\n", __func__, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 924 | rc, |
| 925 | s->auth_tok->token.password.session_key_encryption_key, |
| 926 | mount_crypt_stat->global_default_fn_cipher_key_bytes); |
| 927 | goto out_free_unlock; |
| 928 | } |
| 929 | rc = crypto_blkcipher_decrypt_iv(&s->desc, &s->dst_sg, &s->src_sg, |
| 930 | s->block_aligned_filename_size); |
| 931 | if (rc) { |
| 932 | printk(KERN_ERR "%s: Error attempting to decrypt filename; " |
| 933 | "rc = [%d]\n", __func__, rc); |
| 934 | goto out_free_unlock; |
| 935 | } |
| 936 | s->i = 0; |
| 937 | while (s->decrypted_filename[s->i] != '\0' |
| 938 | && s->i < s->block_aligned_filename_size) |
| 939 | s->i++; |
| 940 | if (s->i == s->block_aligned_filename_size) { |
| 941 | printk(KERN_WARNING "%s: Invalid tag 70 packet; could not " |
| 942 | "find valid separator between random characters and " |
| 943 | "the filename\n", __func__); |
| 944 | rc = -EINVAL; |
| 945 | goto out_free_unlock; |
| 946 | } |
| 947 | s->i++; |
| 948 | (*filename_size) = (s->block_aligned_filename_size - s->i); |
| 949 | if (!((*filename_size) > 0 && (*filename_size < PATH_MAX))) { |
Michael Halcrow | df261c5 | 2009-01-06 14:42:02 -0800 | [diff] [blame] | 950 | printk(KERN_WARNING "%s: Filename size is [%zd], which is " |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 951 | "invalid\n", __func__, (*filename_size)); |
| 952 | rc = -EINVAL; |
| 953 | goto out_free_unlock; |
| 954 | } |
| 955 | (*filename) = kmalloc(((*filename_size) + 1), GFP_KERNEL); |
| 956 | if (!(*filename)) { |
| 957 | printk(KERN_ERR "%s: Out of memory whilst attempting to " |
Michael Halcrow | a8f1286 | 2009-01-06 14:42:03 -0800 | [diff] [blame] | 958 | "kmalloc [%zd] bytes\n", __func__, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 959 | ((*filename_size) + 1)); |
| 960 | rc = -ENOMEM; |
| 961 | goto out_free_unlock; |
| 962 | } |
| 963 | memcpy((*filename), &s->decrypted_filename[s->i], (*filename_size)); |
| 964 | (*filename)[(*filename_size)] = '\0'; |
| 965 | out_free_unlock: |
| 966 | kfree(s->decrypted_filename); |
| 967 | out_unlock: |
| 968 | mutex_unlock(s->tfm_mutex); |
| 969 | out: |
| 970 | if (rc) { |
| 971 | (*packet_size) = 0; |
| 972 | (*filename_size) = 0; |
| 973 | (*filename) = NULL; |
| 974 | } |
| 975 | kfree(s); |
| 976 | return rc; |
| 977 | } |
| 978 | |
| 979 | static int |
Michael Halcrow | cd9d67d | 2007-10-16 01:28:04 -0700 | [diff] [blame] | 980 | ecryptfs_get_auth_tok_sig(char **sig, struct ecryptfs_auth_tok *auth_tok) |
| 981 | { |
| 982 | int rc = 0; |
| 983 | |
| 984 | (*sig) = NULL; |
| 985 | switch (auth_tok->token_type) { |
| 986 | case ECRYPTFS_PASSWORD: |
| 987 | (*sig) = auth_tok->token.password.signature; |
| 988 | break; |
| 989 | case ECRYPTFS_PRIVATE_KEY: |
| 990 | (*sig) = auth_tok->token.private_key.signature; |
| 991 | break; |
| 992 | default: |
| 993 | printk(KERN_ERR "Cannot get sig for auth_tok of type [%d]\n", |
| 994 | auth_tok->token_type); |
| 995 | rc = -EINVAL; |
| 996 | } |
| 997 | return rc; |
| 998 | } |
| 999 | |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1000 | /** |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1001 | * decrypt_pki_encrypted_session_key - Decrypt the session key with the given auth_tok. |
| 1002 | * @auth_tok: The key authentication token used to decrypt the session key |
| 1003 | * @crypt_stat: The cryptographic context |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1004 | * |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1005 | * Returns zero on success; non-zero error otherwise. |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1006 | */ |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1007 | static int |
| 1008 | decrypt_pki_encrypted_session_key(struct ecryptfs_auth_tok *auth_tok, |
| 1009 | struct ecryptfs_crypt_stat *crypt_stat) |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1010 | { |
Trevor Highland | 19e66a6 | 2008-02-06 01:38:36 -0800 | [diff] [blame] | 1011 | u8 cipher_code = 0; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1012 | struct ecryptfs_msg_ctx *msg_ctx; |
| 1013 | struct ecryptfs_message *msg = NULL; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1014 | char *auth_tok_sig; |
Tyler Hicks | 624ae52 | 2008-10-15 22:02:51 -0700 | [diff] [blame] | 1015 | char *payload; |
| 1016 | size_t payload_len; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1017 | int rc; |
| 1018 | |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 1019 | rc = ecryptfs_get_auth_tok_sig(&auth_tok_sig, auth_tok); |
| 1020 | if (rc) { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1021 | printk(KERN_ERR "Unrecognized auth tok type: [%d]\n", |
| 1022 | auth_tok->token_type); |
| 1023 | goto out; |
| 1024 | } |
| 1025 | rc = write_tag_64_packet(auth_tok_sig, &(auth_tok->session_key), |
Tyler Hicks | 624ae52 | 2008-10-15 22:02:51 -0700 | [diff] [blame] | 1026 | &payload, &payload_len); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1027 | if (rc) { |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 1028 | ecryptfs_printk(KERN_ERR, "Failed to write tag 64 packet\n"); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1029 | goto out; |
| 1030 | } |
Tyler Hicks | 624ae52 | 2008-10-15 22:02:51 -0700 | [diff] [blame] | 1031 | rc = ecryptfs_send_message(payload, payload_len, &msg_ctx); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1032 | if (rc) { |
Tyler Hicks | 624ae52 | 2008-10-15 22:02:51 -0700 | [diff] [blame] | 1033 | ecryptfs_printk(KERN_ERR, "Error sending message to " |
| 1034 | "ecryptfsd\n"); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1035 | goto out; |
| 1036 | } |
| 1037 | rc = ecryptfs_wait_for_response(msg_ctx, &msg); |
| 1038 | if (rc) { |
| 1039 | ecryptfs_printk(KERN_ERR, "Failed to receive tag 65 packet " |
| 1040 | "from the user space daemon\n"); |
| 1041 | rc = -EIO; |
| 1042 | goto out; |
| 1043 | } |
| 1044 | rc = parse_tag_65_packet(&(auth_tok->session_key), |
| 1045 | &cipher_code, msg); |
| 1046 | if (rc) { |
| 1047 | printk(KERN_ERR "Failed to parse tag 65 packet; rc = [%d]\n", |
| 1048 | rc); |
| 1049 | goto out; |
| 1050 | } |
| 1051 | auth_tok->session_key.flags |= ECRYPTFS_CONTAINS_DECRYPTED_KEY; |
| 1052 | memcpy(crypt_stat->key, auth_tok->session_key.decrypted_key, |
| 1053 | auth_tok->session_key.decrypted_key_size); |
| 1054 | crypt_stat->key_size = auth_tok->session_key.decrypted_key_size; |
| 1055 | rc = ecryptfs_cipher_code_to_string(crypt_stat->cipher, cipher_code); |
| 1056 | if (rc) { |
| 1057 | ecryptfs_printk(KERN_ERR, "Cipher code [%d] is invalid\n", |
| 1058 | cipher_code) |
| 1059 | goto out; |
| 1060 | } |
| 1061 | crypt_stat->flags |= ECRYPTFS_KEY_VALID; |
| 1062 | if (ecryptfs_verbosity > 0) { |
| 1063 | ecryptfs_printk(KERN_DEBUG, "Decrypted session key:\n"); |
| 1064 | ecryptfs_dump_hex(crypt_stat->key, |
| 1065 | crypt_stat->key_size); |
| 1066 | } |
| 1067 | out: |
| 1068 | if (msg) |
| 1069 | kfree(msg); |
| 1070 | return rc; |
| 1071 | } |
| 1072 | |
| 1073 | static void wipe_auth_tok_list(struct list_head *auth_tok_list_head) |
| 1074 | { |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1075 | struct ecryptfs_auth_tok_list_item *auth_tok_list_item; |
Michael Halcrow | e0869cc | 2007-10-16 01:27:55 -0700 | [diff] [blame] | 1076 | struct ecryptfs_auth_tok_list_item *auth_tok_list_item_tmp; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1077 | |
Michael Halcrow | e0869cc | 2007-10-16 01:27:55 -0700 | [diff] [blame] | 1078 | list_for_each_entry_safe(auth_tok_list_item, auth_tok_list_item_tmp, |
| 1079 | auth_tok_list_head, list) { |
| 1080 | list_del(&auth_tok_list_item->list); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1081 | kmem_cache_free(ecryptfs_auth_tok_list_item_cache, |
| 1082 | auth_tok_list_item); |
| 1083 | } |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1084 | } |
| 1085 | |
| 1086 | struct kmem_cache *ecryptfs_auth_tok_list_item_cache; |
| 1087 | |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1088 | /** |
| 1089 | * parse_tag_1_packet |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1090 | * @crypt_stat: The cryptographic context to modify based on packet contents |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1091 | * @data: The raw bytes of the packet. |
| 1092 | * @auth_tok_list: eCryptfs parses packets into authentication tokens; |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1093 | * a new authentication token will be placed at the |
| 1094 | * end of this list for this packet. |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1095 | * @new_auth_tok: Pointer to a pointer to memory that this function |
| 1096 | * allocates; sets the memory address of the pointer to |
| 1097 | * NULL on error. This object is added to the |
| 1098 | * auth_tok_list. |
| 1099 | * @packet_size: This function writes the size of the parsed packet |
| 1100 | * into this memory location; zero on error. |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1101 | * @max_packet_size: The maximum allowable packet size |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1102 | * |
| 1103 | * Returns zero on success; non-zero on error. |
| 1104 | */ |
| 1105 | static int |
| 1106 | parse_tag_1_packet(struct ecryptfs_crypt_stat *crypt_stat, |
| 1107 | unsigned char *data, struct list_head *auth_tok_list, |
| 1108 | struct ecryptfs_auth_tok **new_auth_tok, |
| 1109 | size_t *packet_size, size_t max_packet_size) |
| 1110 | { |
| 1111 | size_t body_size; |
| 1112 | struct ecryptfs_auth_tok_list_item *auth_tok_list_item; |
| 1113 | size_t length_size; |
| 1114 | int rc = 0; |
| 1115 | |
| 1116 | (*packet_size) = 0; |
| 1117 | (*new_auth_tok) = NULL; |
Michael Halcrow | 1321817 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1118 | /** |
| 1119 | * This format is inspired by OpenPGP; see RFC 2440 |
| 1120 | * packet tag 1 |
| 1121 | * |
| 1122 | * Tag 1 identifier (1 byte) |
| 1123 | * Max Tag 1 packet size (max 3 bytes) |
| 1124 | * Version (1 byte) |
| 1125 | * Key identifier (8 bytes; ECRYPTFS_SIG_SIZE) |
| 1126 | * Cipher identifier (1 byte) |
| 1127 | * Encrypted key size (arbitrary) |
| 1128 | * |
| 1129 | * 12 bytes minimum packet size |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1130 | */ |
Michael Halcrow | 1321817 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1131 | if (unlikely(max_packet_size < 12)) { |
| 1132 | printk(KERN_ERR "Invalid max packet size; must be >=12\n"); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1133 | rc = -EINVAL; |
| 1134 | goto out; |
| 1135 | } |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1136 | if (data[(*packet_size)++] != ECRYPTFS_TAG_1_PACKET_TYPE) { |
Michael Halcrow | 1321817 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1137 | printk(KERN_ERR "Enter w/ first byte != 0x%.2x\n", |
| 1138 | ECRYPTFS_TAG_1_PACKET_TYPE); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1139 | rc = -EINVAL; |
| 1140 | goto out; |
| 1141 | } |
| 1142 | /* Released: wipe_auth_tok_list called in ecryptfs_parse_packet_set or |
| 1143 | * at end of function upon failure */ |
| 1144 | auth_tok_list_item = |
Michael Halcrow | 1321817 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1145 | kmem_cache_zalloc(ecryptfs_auth_tok_list_item_cache, |
| 1146 | GFP_KERNEL); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1147 | if (!auth_tok_list_item) { |
Michael Halcrow | 1321817 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1148 | printk(KERN_ERR "Unable to allocate memory\n"); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1149 | rc = -ENOMEM; |
| 1150 | goto out; |
| 1151 | } |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1152 | (*new_auth_tok) = &auth_tok_list_item->auth_tok; |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 1153 | rc = ecryptfs_parse_packet_length(&data[(*packet_size)], &body_size, |
| 1154 | &length_size); |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 1155 | if (rc) { |
Michael Halcrow | 1321817 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1156 | printk(KERN_WARNING "Error parsing packet length; " |
| 1157 | "rc = [%d]\n", rc); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1158 | goto out_free; |
| 1159 | } |
Michael Halcrow | 1321817 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1160 | if (unlikely(body_size < (ECRYPTFS_SIG_SIZE + 2))) { |
Andrew Morton | 81acbcd | 2007-10-16 01:27:59 -0700 | [diff] [blame] | 1161 | printk(KERN_WARNING "Invalid body size ([%td])\n", body_size); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1162 | rc = -EINVAL; |
| 1163 | goto out_free; |
| 1164 | } |
| 1165 | (*packet_size) += length_size; |
| 1166 | if (unlikely((*packet_size) + body_size > max_packet_size)) { |
Michael Halcrow | 1321817 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1167 | printk(KERN_WARNING "Packet size exceeds max\n"); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1168 | rc = -EINVAL; |
| 1169 | goto out_free; |
| 1170 | } |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1171 | if (unlikely(data[(*packet_size)++] != 0x03)) { |
Michael Halcrow | 1321817 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1172 | printk(KERN_WARNING "Unknown version number [%d]\n", |
| 1173 | data[(*packet_size) - 1]); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1174 | rc = -EINVAL; |
| 1175 | goto out_free; |
| 1176 | } |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1177 | ecryptfs_to_hex((*new_auth_tok)->token.private_key.signature, |
| 1178 | &data[(*packet_size)], ECRYPTFS_SIG_SIZE); |
| 1179 | *packet_size += ECRYPTFS_SIG_SIZE; |
| 1180 | /* This byte is skipped because the kernel does not need to |
| 1181 | * know which public key encryption algorithm was used */ |
| 1182 | (*packet_size)++; |
| 1183 | (*new_auth_tok)->session_key.encrypted_key_size = |
Michael Halcrow | 1321817 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1184 | body_size - (ECRYPTFS_SIG_SIZE + 2); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1185 | if ((*new_auth_tok)->session_key.encrypted_key_size |
| 1186 | > ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES) { |
Michael Halcrow | 1321817 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1187 | printk(KERN_WARNING "Tag 1 packet contains key larger " |
| 1188 | "than ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES"); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1189 | rc = -EINVAL; |
| 1190 | goto out; |
| 1191 | } |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1192 | memcpy((*new_auth_tok)->session_key.encrypted_key, |
Michael Halcrow | 1321817 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1193 | &data[(*packet_size)], (body_size - (ECRYPTFS_SIG_SIZE + 2))); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1194 | (*packet_size) += (*new_auth_tok)->session_key.encrypted_key_size; |
| 1195 | (*new_auth_tok)->session_key.flags &= |
| 1196 | ~ECRYPTFS_CONTAINS_DECRYPTED_KEY; |
| 1197 | (*new_auth_tok)->session_key.flags |= |
| 1198 | ECRYPTFS_CONTAINS_ENCRYPTED_KEY; |
| 1199 | (*new_auth_tok)->token_type = ECRYPTFS_PRIVATE_KEY; |
Michael Halcrow | 1321817 | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1200 | (*new_auth_tok)->flags = 0; |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 1201 | (*new_auth_tok)->session_key.flags &= |
| 1202 | ~(ECRYPTFS_USERSPACE_SHOULD_TRY_TO_DECRYPT); |
| 1203 | (*new_auth_tok)->session_key.flags &= |
| 1204 | ~(ECRYPTFS_USERSPACE_SHOULD_TRY_TO_ENCRYPT); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1205 | list_add(&auth_tok_list_item->list, auth_tok_list); |
| 1206 | goto out; |
| 1207 | out_free: |
| 1208 | (*new_auth_tok) = NULL; |
| 1209 | memset(auth_tok_list_item, 0, |
| 1210 | sizeof(struct ecryptfs_auth_tok_list_item)); |
| 1211 | kmem_cache_free(ecryptfs_auth_tok_list_item_cache, |
| 1212 | auth_tok_list_item); |
| 1213 | out: |
| 1214 | if (rc) |
| 1215 | (*packet_size) = 0; |
| 1216 | return rc; |
| 1217 | } |
| 1218 | |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1219 | /** |
| 1220 | * parse_tag_3_packet |
| 1221 | * @crypt_stat: The cryptographic context to modify based on packet |
| 1222 | * contents. |
| 1223 | * @data: The raw bytes of the packet. |
| 1224 | * @auth_tok_list: eCryptfs parses packets into authentication tokens; |
| 1225 | * a new authentication token will be placed at the end |
| 1226 | * of this list for this packet. |
| 1227 | * @new_auth_tok: Pointer to a pointer to memory that this function |
| 1228 | * allocates; sets the memory address of the pointer to |
| 1229 | * NULL on error. This object is added to the |
| 1230 | * auth_tok_list. |
| 1231 | * @packet_size: This function writes the size of the parsed packet |
| 1232 | * into this memory location; zero on error. |
| 1233 | * @max_packet_size: maximum number of bytes to parse |
| 1234 | * |
| 1235 | * Returns zero on success; non-zero on error. |
| 1236 | */ |
| 1237 | static int |
| 1238 | parse_tag_3_packet(struct ecryptfs_crypt_stat *crypt_stat, |
| 1239 | unsigned char *data, struct list_head *auth_tok_list, |
| 1240 | struct ecryptfs_auth_tok **new_auth_tok, |
| 1241 | size_t *packet_size, size_t max_packet_size) |
| 1242 | { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1243 | size_t body_size; |
| 1244 | struct ecryptfs_auth_tok_list_item *auth_tok_list_item; |
| 1245 | size_t length_size; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1246 | int rc = 0; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1247 | |
| 1248 | (*packet_size) = 0; |
| 1249 | (*new_auth_tok) = NULL; |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1250 | /** |
| 1251 | *This format is inspired by OpenPGP; see RFC 2440 |
| 1252 | * packet tag 3 |
| 1253 | * |
| 1254 | * Tag 3 identifier (1 byte) |
| 1255 | * Max Tag 3 packet size (max 3 bytes) |
| 1256 | * Version (1 byte) |
| 1257 | * Cipher code (1 byte) |
| 1258 | * S2K specifier (1 byte) |
| 1259 | * Hash identifier (1 byte) |
| 1260 | * Salt (ECRYPTFS_SALT_SIZE) |
| 1261 | * Hash iterations (1 byte) |
| 1262 | * Encrypted key (arbitrary) |
| 1263 | * |
| 1264 | * (ECRYPTFS_SALT_SIZE + 7) minimum packet size |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1265 | */ |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1266 | if (max_packet_size < (ECRYPTFS_SALT_SIZE + 7)) { |
| 1267 | printk(KERN_ERR "Max packet size too large\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1268 | rc = -EINVAL; |
| 1269 | goto out; |
| 1270 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1271 | if (data[(*packet_size)++] != ECRYPTFS_TAG_3_PACKET_TYPE) { |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1272 | printk(KERN_ERR "First byte != 0x%.2x; invalid packet\n", |
| 1273 | ECRYPTFS_TAG_3_PACKET_TYPE); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1274 | rc = -EINVAL; |
| 1275 | goto out; |
| 1276 | } |
| 1277 | /* Released: wipe_auth_tok_list called in ecryptfs_parse_packet_set or |
| 1278 | * at end of function upon failure */ |
| 1279 | auth_tok_list_item = |
Robert P. J. Day | c376222 | 2007-02-10 01:45:03 -0800 | [diff] [blame] | 1280 | kmem_cache_zalloc(ecryptfs_auth_tok_list_item_cache, GFP_KERNEL); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1281 | if (!auth_tok_list_item) { |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1282 | printk(KERN_ERR "Unable to allocate memory\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1283 | rc = -ENOMEM; |
| 1284 | goto out; |
| 1285 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1286 | (*new_auth_tok) = &auth_tok_list_item->auth_tok; |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 1287 | rc = ecryptfs_parse_packet_length(&data[(*packet_size)], &body_size, |
| 1288 | &length_size); |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 1289 | if (rc) { |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1290 | printk(KERN_WARNING "Error parsing packet length; rc = [%d]\n", |
| 1291 | rc); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1292 | goto out_free; |
| 1293 | } |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1294 | if (unlikely(body_size < (ECRYPTFS_SALT_SIZE + 5))) { |
Andrew Morton | 81acbcd | 2007-10-16 01:27:59 -0700 | [diff] [blame] | 1295 | printk(KERN_WARNING "Invalid body size ([%td])\n", body_size); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1296 | rc = -EINVAL; |
| 1297 | goto out_free; |
| 1298 | } |
| 1299 | (*packet_size) += length_size; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1300 | if (unlikely((*packet_size) + body_size > max_packet_size)) { |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1301 | printk(KERN_ERR "Packet size exceeds max\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1302 | rc = -EINVAL; |
| 1303 | goto out_free; |
| 1304 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1305 | (*new_auth_tok)->session_key.encrypted_key_size = |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1306 | (body_size - (ECRYPTFS_SALT_SIZE + 5)); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1307 | if (unlikely(data[(*packet_size)++] != 0x04)) { |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1308 | printk(KERN_WARNING "Unknown version number [%d]\n", |
| 1309 | data[(*packet_size) - 1]); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1310 | rc = -EINVAL; |
| 1311 | goto out_free; |
| 1312 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1313 | ecryptfs_cipher_code_to_string(crypt_stat->cipher, |
| 1314 | (u16)data[(*packet_size)]); |
| 1315 | /* A little extra work to differentiate among the AES key |
| 1316 | * sizes; see RFC2440 */ |
| 1317 | switch(data[(*packet_size)++]) { |
| 1318 | case RFC2440_CIPHER_AES_192: |
| 1319 | crypt_stat->key_size = 24; |
| 1320 | break; |
| 1321 | default: |
| 1322 | crypt_stat->key_size = |
| 1323 | (*new_auth_tok)->session_key.encrypted_key_size; |
| 1324 | } |
| 1325 | ecryptfs_init_crypt_ctx(crypt_stat); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1326 | if (unlikely(data[(*packet_size)++] != 0x03)) { |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1327 | printk(KERN_WARNING "Only S2K ID 3 is currently supported\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1328 | rc = -ENOSYS; |
| 1329 | goto out_free; |
| 1330 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1331 | /* TODO: finish the hash mapping */ |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1332 | switch (data[(*packet_size)++]) { |
| 1333 | case 0x01: /* See RFC2440 for these numbers and their mappings */ |
| 1334 | /* Choose MD5 */ |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1335 | memcpy((*new_auth_tok)->token.password.salt, |
| 1336 | &data[(*packet_size)], ECRYPTFS_SALT_SIZE); |
| 1337 | (*packet_size) += ECRYPTFS_SALT_SIZE; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1338 | /* This conversion was taken straight from RFC2440 */ |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1339 | (*new_auth_tok)->token.password.hash_iterations = |
| 1340 | ((u32) 16 + (data[(*packet_size)] & 15)) |
| 1341 | << ((data[(*packet_size)] >> 4) + 6); |
| 1342 | (*packet_size)++; |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1343 | /* Friendly reminder: |
| 1344 | * (*new_auth_tok)->session_key.encrypted_key_size = |
| 1345 | * (body_size - (ECRYPTFS_SALT_SIZE + 5)); */ |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1346 | memcpy((*new_auth_tok)->session_key.encrypted_key, |
| 1347 | &data[(*packet_size)], |
| 1348 | (*new_auth_tok)->session_key.encrypted_key_size); |
| 1349 | (*packet_size) += |
| 1350 | (*new_auth_tok)->session_key.encrypted_key_size; |
| 1351 | (*new_auth_tok)->session_key.flags &= |
| 1352 | ~ECRYPTFS_CONTAINS_DECRYPTED_KEY; |
| 1353 | (*new_auth_tok)->session_key.flags |= |
| 1354 | ECRYPTFS_CONTAINS_ENCRYPTED_KEY; |
Michael Halcrow | c59becf | 2007-10-16 01:27:56 -0700 | [diff] [blame] | 1355 | (*new_auth_tok)->token.password.hash_algo = 0x01; /* MD5 */ |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1356 | break; |
| 1357 | default: |
| 1358 | ecryptfs_printk(KERN_ERR, "Unsupported hash algorithm: " |
| 1359 | "[%d]\n", data[(*packet_size) - 1]); |
| 1360 | rc = -ENOSYS; |
| 1361 | goto out_free; |
| 1362 | } |
| 1363 | (*new_auth_tok)->token_type = ECRYPTFS_PASSWORD; |
| 1364 | /* TODO: Parametarize; we might actually want userspace to |
| 1365 | * decrypt the session key. */ |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 1366 | (*new_auth_tok)->session_key.flags &= |
| 1367 | ~(ECRYPTFS_USERSPACE_SHOULD_TRY_TO_DECRYPT); |
| 1368 | (*new_auth_tok)->session_key.flags &= |
| 1369 | ~(ECRYPTFS_USERSPACE_SHOULD_TRY_TO_ENCRYPT); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1370 | list_add(&auth_tok_list_item->list, auth_tok_list); |
| 1371 | goto out; |
| 1372 | out_free: |
| 1373 | (*new_auth_tok) = NULL; |
| 1374 | memset(auth_tok_list_item, 0, |
| 1375 | sizeof(struct ecryptfs_auth_tok_list_item)); |
| 1376 | kmem_cache_free(ecryptfs_auth_tok_list_item_cache, |
| 1377 | auth_tok_list_item); |
| 1378 | out: |
| 1379 | if (rc) |
| 1380 | (*packet_size) = 0; |
| 1381 | return rc; |
| 1382 | } |
| 1383 | |
| 1384 | /** |
| 1385 | * parse_tag_11_packet |
| 1386 | * @data: The raw bytes of the packet |
| 1387 | * @contents: This function writes the data contents of the literal |
| 1388 | * packet into this memory location |
| 1389 | * @max_contents_bytes: The maximum number of bytes that this function |
| 1390 | * is allowed to write into contents |
| 1391 | * @tag_11_contents_size: This function writes the size of the parsed |
| 1392 | * contents into this memory location; zero on |
| 1393 | * error |
| 1394 | * @packet_size: This function writes the size of the parsed packet |
| 1395 | * into this memory location; zero on error |
| 1396 | * @max_packet_size: maximum number of bytes to parse |
| 1397 | * |
| 1398 | * Returns zero on success; non-zero on error. |
| 1399 | */ |
| 1400 | static int |
| 1401 | parse_tag_11_packet(unsigned char *data, unsigned char *contents, |
| 1402 | size_t max_contents_bytes, size_t *tag_11_contents_size, |
| 1403 | size_t *packet_size, size_t max_packet_size) |
| 1404 | { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1405 | size_t body_size; |
| 1406 | size_t length_size; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1407 | int rc = 0; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1408 | |
| 1409 | (*packet_size) = 0; |
| 1410 | (*tag_11_contents_size) = 0; |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1411 | /* This format is inspired by OpenPGP; see RFC 2440 |
| 1412 | * packet tag 11 |
| 1413 | * |
| 1414 | * Tag 11 identifier (1 byte) |
| 1415 | * Max Tag 11 packet size (max 3 bytes) |
| 1416 | * Binary format specifier (1 byte) |
| 1417 | * Filename length (1 byte) |
| 1418 | * Filename ("_CONSOLE") (8 bytes) |
| 1419 | * Modification date (4 bytes) |
| 1420 | * Literal data (arbitrary) |
| 1421 | * |
| 1422 | * We need at least 16 bytes of data for the packet to even be |
| 1423 | * valid. |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1424 | */ |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1425 | if (max_packet_size < 16) { |
| 1426 | printk(KERN_ERR "Maximum packet size too small\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1427 | rc = -EINVAL; |
| 1428 | goto out; |
| 1429 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1430 | if (data[(*packet_size)++] != ECRYPTFS_TAG_11_PACKET_TYPE) { |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1431 | printk(KERN_WARNING "Invalid tag 11 packet format\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1432 | rc = -EINVAL; |
| 1433 | goto out; |
| 1434 | } |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 1435 | rc = ecryptfs_parse_packet_length(&data[(*packet_size)], &body_size, |
| 1436 | &length_size); |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 1437 | if (rc) { |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1438 | printk(KERN_WARNING "Invalid tag 11 packet format\n"); |
| 1439 | goto out; |
| 1440 | } |
| 1441 | if (body_size < 14) { |
Andrew Morton | 81acbcd | 2007-10-16 01:27:59 -0700 | [diff] [blame] | 1442 | printk(KERN_WARNING "Invalid body size ([%td])\n", body_size); |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1443 | rc = -EINVAL; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1444 | goto out; |
| 1445 | } |
| 1446 | (*packet_size) += length_size; |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1447 | (*tag_11_contents_size) = (body_size - 14); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1448 | if (unlikely((*packet_size) + body_size + 1 > max_packet_size)) { |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1449 | printk(KERN_ERR "Packet size exceeds max\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1450 | rc = -EINVAL; |
| 1451 | goto out; |
| 1452 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1453 | if (data[(*packet_size)++] != 0x62) { |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1454 | printk(KERN_WARNING "Unrecognizable packet\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1455 | rc = -EINVAL; |
| 1456 | goto out; |
| 1457 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1458 | if (data[(*packet_size)++] != 0x08) { |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1459 | printk(KERN_WARNING "Unrecognizable packet\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1460 | rc = -EINVAL; |
| 1461 | goto out; |
| 1462 | } |
Michael Halcrow | f648104 | 2007-10-16 01:27:57 -0700 | [diff] [blame] | 1463 | (*packet_size) += 12; /* Ignore filename and modification date */ |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1464 | memcpy(contents, &data[(*packet_size)], (*tag_11_contents_size)); |
| 1465 | (*packet_size) += (*tag_11_contents_size); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1466 | out: |
| 1467 | if (rc) { |
| 1468 | (*packet_size) = 0; |
| 1469 | (*tag_11_contents_size) = 0; |
| 1470 | } |
| 1471 | return rc; |
| 1472 | } |
| 1473 | |
| 1474 | /** |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1475 | * ecryptfs_verify_version |
| 1476 | * @version: The version number to confirm |
| 1477 | * |
| 1478 | * Returns zero on good version; non-zero otherwise |
| 1479 | */ |
| 1480 | static int ecryptfs_verify_version(u16 version) |
| 1481 | { |
| 1482 | int rc = 0; |
| 1483 | unsigned char major; |
| 1484 | unsigned char minor; |
| 1485 | |
| 1486 | major = ((version >> 8) & 0xFF); |
| 1487 | minor = (version & 0xFF); |
| 1488 | if (major != ECRYPTFS_VERSION_MAJOR) { |
| 1489 | ecryptfs_printk(KERN_ERR, "Major version number mismatch. " |
| 1490 | "Expected [%d]; got [%d]\n", |
| 1491 | ECRYPTFS_VERSION_MAJOR, major); |
| 1492 | rc = -EINVAL; |
| 1493 | goto out; |
| 1494 | } |
| 1495 | if (minor != ECRYPTFS_VERSION_MINOR) { |
| 1496 | ecryptfs_printk(KERN_ERR, "Minor version number mismatch. " |
| 1497 | "Expected [%d]; got [%d]\n", |
| 1498 | ECRYPTFS_VERSION_MINOR, minor); |
| 1499 | rc = -EINVAL; |
| 1500 | goto out; |
| 1501 | } |
| 1502 | out: |
| 1503 | return rc; |
| 1504 | } |
| 1505 | |
| 1506 | int ecryptfs_keyring_auth_tok_for_sig(struct key **auth_tok_key, |
| 1507 | struct ecryptfs_auth_tok **auth_tok, |
| 1508 | char *sig) |
| 1509 | { |
| 1510 | int rc = 0; |
| 1511 | |
| 1512 | (*auth_tok_key) = request_key(&key_type_user, sig, NULL); |
| 1513 | if (!(*auth_tok_key) || IS_ERR(*auth_tok_key)) { |
| 1514 | printk(KERN_ERR "Could not find key with description: [%s]\n", |
| 1515 | sig); |
Eric Sandeen | 982363c | 2008-07-23 21:30:04 -0700 | [diff] [blame] | 1516 | rc = process_request_key_err(PTR_ERR(*auth_tok_key)); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1517 | goto out; |
| 1518 | } |
| 1519 | (*auth_tok) = ecryptfs_get_key_payload_data(*auth_tok_key); |
| 1520 | if (ecryptfs_verify_version((*auth_tok)->version)) { |
| 1521 | printk(KERN_ERR |
| 1522 | "Data structure version mismatch. " |
| 1523 | "Userspace tools must match eCryptfs " |
| 1524 | "kernel module with major version [%d] " |
| 1525 | "and minor version [%d]\n", |
| 1526 | ECRYPTFS_VERSION_MAJOR, |
| 1527 | ECRYPTFS_VERSION_MINOR); |
| 1528 | rc = -EINVAL; |
| 1529 | goto out; |
| 1530 | } |
| 1531 | if ((*auth_tok)->token_type != ECRYPTFS_PASSWORD |
| 1532 | && (*auth_tok)->token_type != ECRYPTFS_PRIVATE_KEY) { |
| 1533 | printk(KERN_ERR "Invalid auth_tok structure " |
| 1534 | "returned from key query\n"); |
| 1535 | rc = -EINVAL; |
| 1536 | goto out; |
| 1537 | } |
| 1538 | out: |
| 1539 | return rc; |
| 1540 | } |
| 1541 | |
| 1542 | /** |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1543 | * decrypt_passphrase_encrypted_session_key - Decrypt the session key with the given auth_tok. |
| 1544 | * @auth_tok: The passphrase authentication token to use to encrypt the FEK |
| 1545 | * @crypt_stat: The cryptographic context |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1546 | * |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1547 | * Returns zero on success; non-zero error otherwise |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1548 | */ |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1549 | static int |
| 1550 | decrypt_passphrase_encrypted_session_key(struct ecryptfs_auth_tok *auth_tok, |
| 1551 | struct ecryptfs_crypt_stat *crypt_stat) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1552 | { |
Michael Halcrow | ac97b9f | 2008-11-19 15:36:28 -0800 | [diff] [blame] | 1553 | struct scatterlist dst_sg[2]; |
| 1554 | struct scatterlist src_sg[2]; |
Michael Halcrow | dd8e290 | 2007-10-16 01:28:03 -0700 | [diff] [blame] | 1555 | struct mutex *tfm_mutex; |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 1556 | struct blkcipher_desc desc = { |
| 1557 | .flags = CRYPTO_TFM_REQ_MAY_SLEEP |
| 1558 | }; |
| 1559 | int rc = 0; |
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 | if (unlikely(ecryptfs_verbosity > 0)) { |
| 1562 | ecryptfs_printk( |
| 1563 | KERN_DEBUG, "Session key encryption key (size [%d]):\n", |
| 1564 | auth_tok->token.password.session_key_encryption_key_bytes); |
| 1565 | ecryptfs_dump_hex( |
| 1566 | auth_tok->token.password.session_key_encryption_key, |
| 1567 | auth_tok->token.password.session_key_encryption_key_bytes); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1568 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1569 | rc = ecryptfs_get_tfm_and_mutex_for_cipher_name(&desc.tfm, &tfm_mutex, |
| 1570 | crypt_stat->cipher); |
| 1571 | if (unlikely(rc)) { |
| 1572 | printk(KERN_ERR "Internal error whilst attempting to get " |
| 1573 | "tfm and mutex for cipher name [%s]; rc = [%d]\n", |
| 1574 | crypt_stat->cipher, rc); |
| 1575 | goto out; |
| 1576 | } |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 1577 | rc = virt_to_scatterlist(auth_tok->session_key.encrypted_key, |
| 1578 | auth_tok->session_key.encrypted_key_size, |
Michael Halcrow | ac97b9f | 2008-11-19 15:36:28 -0800 | [diff] [blame] | 1579 | src_sg, 2); |
| 1580 | if (rc < 1 || rc > 2) { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1581 | printk(KERN_ERR "Internal error whilst attempting to convert " |
| 1582 | "auth_tok->session_key.encrypted_key to scatterlist; " |
| 1583 | "expected rc = 1; got rc = [%d]. " |
| 1584 | "auth_tok->session_key.encrypted_key_size = [%d]\n", rc, |
| 1585 | auth_tok->session_key.encrypted_key_size); |
| 1586 | goto out; |
| 1587 | } |
| 1588 | auth_tok->session_key.decrypted_key_size = |
| 1589 | auth_tok->session_key.encrypted_key_size; |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 1590 | rc = virt_to_scatterlist(auth_tok->session_key.decrypted_key, |
| 1591 | auth_tok->session_key.decrypted_key_size, |
Michael Halcrow | ac97b9f | 2008-11-19 15:36:28 -0800 | [diff] [blame] | 1592 | dst_sg, 2); |
| 1593 | if (rc < 1 || rc > 2) { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1594 | printk(KERN_ERR "Internal error whilst attempting to convert " |
| 1595 | "auth_tok->session_key.decrypted_key to scatterlist; " |
| 1596 | "expected rc = 1; got rc = [%d]\n", rc); |
| 1597 | goto out; |
| 1598 | } |
| 1599 | mutex_lock(tfm_mutex); |
| 1600 | rc = crypto_blkcipher_setkey( |
| 1601 | desc.tfm, auth_tok->token.password.session_key_encryption_key, |
| 1602 | crypt_stat->key_size); |
| 1603 | if (unlikely(rc < 0)) { |
| 1604 | mutex_unlock(tfm_mutex); |
Michael Halcrow | e5d9cbd | 2006-10-30 22:07:16 -0800 | [diff] [blame] | 1605 | printk(KERN_ERR "Error setting key for crypto context\n"); |
| 1606 | rc = -EINVAL; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1607 | goto out; |
Michael Halcrow | e5d9cbd | 2006-10-30 22:07:16 -0800 | [diff] [blame] | 1608 | } |
Michael Halcrow | ac97b9f | 2008-11-19 15:36:28 -0800 | [diff] [blame] | 1609 | rc = crypto_blkcipher_decrypt(&desc, dst_sg, src_sg, |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 1610 | auth_tok->session_key.encrypted_key_size); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1611 | mutex_unlock(tfm_mutex); |
| 1612 | if (unlikely(rc)) { |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 1613 | printk(KERN_ERR "Error decrypting; rc = [%d]\n", rc); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1614 | goto out; |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 1615 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1616 | auth_tok->session_key.flags |= ECRYPTFS_CONTAINS_DECRYPTED_KEY; |
| 1617 | memcpy(crypt_stat->key, auth_tok->session_key.decrypted_key, |
| 1618 | auth_tok->session_key.decrypted_key_size); |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 1619 | crypt_stat->flags |= ECRYPTFS_KEY_VALID; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1620 | if (unlikely(ecryptfs_verbosity > 0)) { |
| 1621 | ecryptfs_printk(KERN_DEBUG, "FEK of size [%d]:\n", |
| 1622 | crypt_stat->key_size); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1623 | ecryptfs_dump_hex(crypt_stat->key, |
| 1624 | crypt_stat->key_size); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1625 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1626 | out: |
| 1627 | return rc; |
| 1628 | } |
| 1629 | |
| 1630 | /** |
| 1631 | * ecryptfs_parse_packet_set |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1632 | * @crypt_stat: The cryptographic context |
| 1633 | * @src: Virtual address of region of memory containing the packets |
| 1634 | * @ecryptfs_dentry: The eCryptfs dentry associated with the packet set |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1635 | * |
| 1636 | * Get crypt_stat to have the file's session key if the requisite key |
| 1637 | * is available to decrypt the session key. |
| 1638 | * |
| 1639 | * Returns Zero if a valid authentication token was retrieved and |
| 1640 | * processed; negative value for file not encrypted or for error |
| 1641 | * conditions. |
| 1642 | */ |
| 1643 | int ecryptfs_parse_packet_set(struct ecryptfs_crypt_stat *crypt_stat, |
| 1644 | unsigned char *src, |
| 1645 | struct dentry *ecryptfs_dentry) |
| 1646 | { |
| 1647 | size_t i = 0; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1648 | size_t found_auth_tok; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1649 | size_t next_packet_is_auth_tok_packet; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1650 | struct list_head auth_tok_list; |
Michael Halcrow | dd8e290 | 2007-10-16 01:28:03 -0700 | [diff] [blame] | 1651 | struct ecryptfs_auth_tok *matching_auth_tok; |
| 1652 | struct ecryptfs_auth_tok *candidate_auth_tok; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1653 | char *candidate_auth_tok_sig; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1654 | size_t packet_size; |
| 1655 | struct ecryptfs_auth_tok *new_auth_tok; |
| 1656 | unsigned char sig_tmp_space[ECRYPTFS_SIG_SIZE]; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1657 | struct ecryptfs_auth_tok_list_item *auth_tok_list_item; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1658 | size_t tag_11_contents_size; |
| 1659 | size_t tag_11_packet_size; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1660 | int rc = 0; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1661 | |
| 1662 | INIT_LIST_HEAD(&auth_tok_list); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1663 | /* 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] | 1664 | * added the our &auth_tok_list */ |
| 1665 | next_packet_is_auth_tok_packet = 1; |
| 1666 | while (next_packet_is_auth_tok_packet) { |
| 1667 | size_t max_packet_size = ((PAGE_CACHE_SIZE - 8) - i); |
| 1668 | |
| 1669 | switch (src[i]) { |
| 1670 | case ECRYPTFS_TAG_3_PACKET_TYPE: |
| 1671 | rc = parse_tag_3_packet(crypt_stat, |
| 1672 | (unsigned char *)&src[i], |
| 1673 | &auth_tok_list, &new_auth_tok, |
| 1674 | &packet_size, max_packet_size); |
| 1675 | if (rc) { |
| 1676 | ecryptfs_printk(KERN_ERR, "Error parsing " |
| 1677 | "tag 3 packet\n"); |
| 1678 | rc = -EIO; |
| 1679 | goto out_wipe_list; |
| 1680 | } |
| 1681 | i += packet_size; |
| 1682 | rc = parse_tag_11_packet((unsigned char *)&src[i], |
| 1683 | sig_tmp_space, |
| 1684 | ECRYPTFS_SIG_SIZE, |
| 1685 | &tag_11_contents_size, |
| 1686 | &tag_11_packet_size, |
| 1687 | max_packet_size); |
| 1688 | if (rc) { |
| 1689 | ecryptfs_printk(KERN_ERR, "No valid " |
| 1690 | "(ecryptfs-specific) literal " |
| 1691 | "packet containing " |
| 1692 | "authentication token " |
| 1693 | "signature found after " |
| 1694 | "tag 3 packet\n"); |
| 1695 | rc = -EIO; |
| 1696 | goto out_wipe_list; |
| 1697 | } |
| 1698 | i += tag_11_packet_size; |
| 1699 | if (ECRYPTFS_SIG_SIZE != tag_11_contents_size) { |
| 1700 | ecryptfs_printk(KERN_ERR, "Expected " |
| 1701 | "signature of size [%d]; " |
| 1702 | "read size [%d]\n", |
| 1703 | ECRYPTFS_SIG_SIZE, |
| 1704 | tag_11_contents_size); |
| 1705 | rc = -EIO; |
| 1706 | goto out_wipe_list; |
| 1707 | } |
| 1708 | ecryptfs_to_hex(new_auth_tok->token.password.signature, |
| 1709 | sig_tmp_space, tag_11_contents_size); |
| 1710 | new_auth_tok->token.password.signature[ |
| 1711 | ECRYPTFS_PASSWORD_SIG_SIZE] = '\0'; |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 1712 | crypt_stat->flags |= ECRYPTFS_ENCRYPTED; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1713 | break; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1714 | case ECRYPTFS_TAG_1_PACKET_TYPE: |
| 1715 | rc = parse_tag_1_packet(crypt_stat, |
| 1716 | (unsigned char *)&src[i], |
| 1717 | &auth_tok_list, &new_auth_tok, |
| 1718 | &packet_size, max_packet_size); |
| 1719 | if (rc) { |
| 1720 | ecryptfs_printk(KERN_ERR, "Error parsing " |
| 1721 | "tag 1 packet\n"); |
| 1722 | rc = -EIO; |
| 1723 | goto out_wipe_list; |
| 1724 | } |
| 1725 | i += packet_size; |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 1726 | crypt_stat->flags |= ECRYPTFS_ENCRYPTED; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1727 | break; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1728 | case ECRYPTFS_TAG_11_PACKET_TYPE: |
| 1729 | ecryptfs_printk(KERN_WARNING, "Invalid packet set " |
| 1730 | "(Tag 11 not allowed by itself)\n"); |
| 1731 | rc = -EIO; |
| 1732 | goto out_wipe_list; |
| 1733 | break; |
| 1734 | default: |
| 1735 | ecryptfs_printk(KERN_DEBUG, "No packet at offset " |
| 1736 | "[%d] of the file header; hex value of " |
| 1737 | "character is [0x%.2x]\n", i, src[i]); |
| 1738 | next_packet_is_auth_tok_packet = 0; |
| 1739 | } |
| 1740 | } |
| 1741 | if (list_empty(&auth_tok_list)) { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1742 | printk(KERN_ERR "The lower file appears to be a non-encrypted " |
| 1743 | "eCryptfs file; this is not supported in this version " |
| 1744 | "of the eCryptfs kernel module\n"); |
| 1745 | rc = -EINVAL; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1746 | goto out; |
| 1747 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1748 | /* auth_tok_list contains the set of authentication tokens |
| 1749 | * parsed from the metadata. We need to find a matching |
| 1750 | * authentication token that has the secret component(s) |
| 1751 | * necessary to decrypt the EFEK in the auth_tok parsed from |
| 1752 | * the metadata. There may be several potential matches, but |
| 1753 | * just one will be sufficient to decrypt to get the FEK. */ |
| 1754 | find_next_matching_auth_tok: |
| 1755 | found_auth_tok = 0; |
| 1756 | list_for_each_entry(auth_tok_list_item, &auth_tok_list, list) { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1757 | candidate_auth_tok = &auth_tok_list_item->auth_tok; |
| 1758 | if (unlikely(ecryptfs_verbosity > 0)) { |
| 1759 | ecryptfs_printk(KERN_DEBUG, |
| 1760 | "Considering cadidate auth tok:\n"); |
| 1761 | ecryptfs_dump_auth_tok(candidate_auth_tok); |
| 1762 | } |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 1763 | rc = ecryptfs_get_auth_tok_sig(&candidate_auth_tok_sig, |
| 1764 | candidate_auth_tok); |
| 1765 | if (rc) { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1766 | printk(KERN_ERR |
| 1767 | "Unrecognized candidate auth tok type: [%d]\n", |
| 1768 | candidate_auth_tok->token_type); |
| 1769 | rc = -EINVAL; |
| 1770 | goto out_wipe_list; |
| 1771 | } |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 1772 | ecryptfs_find_auth_tok_for_sig(&matching_auth_tok, |
| 1773 | crypt_stat->mount_crypt_stat, |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 1774 | candidate_auth_tok_sig); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1775 | if (matching_auth_tok) { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1776 | found_auth_tok = 1; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1777 | goto found_matching_auth_tok; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1778 | } |
| 1779 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1780 | if (!found_auth_tok) { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1781 | ecryptfs_printk(KERN_ERR, "Could not find a usable " |
| 1782 | "authentication token\n"); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1783 | rc = -EIO; |
| 1784 | goto out_wipe_list; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1785 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1786 | found_matching_auth_tok: |
Michael Halcrow | e2bd99e | 2007-02-12 00:53:49 -0800 | [diff] [blame] | 1787 | if (candidate_auth_tok->token_type == ECRYPTFS_PRIVATE_KEY) { |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1788 | memcpy(&(candidate_auth_tok->token.private_key), |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1789 | &(matching_auth_tok->token.private_key), |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1790 | sizeof(struct ecryptfs_private_key)); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1791 | rc = decrypt_pki_encrypted_session_key(candidate_auth_tok, |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1792 | crypt_stat); |
| 1793 | } else if (candidate_auth_tok->token_type == ECRYPTFS_PASSWORD) { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1794 | memcpy(&(candidate_auth_tok->token.password), |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1795 | &(matching_auth_tok->token.password), |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1796 | sizeof(struct ecryptfs_password)); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1797 | rc = decrypt_passphrase_encrypted_session_key( |
| 1798 | candidate_auth_tok, crypt_stat); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1799 | } |
| 1800 | if (rc) { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1801 | struct ecryptfs_auth_tok_list_item *auth_tok_list_item_tmp; |
| 1802 | |
| 1803 | ecryptfs_printk(KERN_WARNING, "Error decrypting the " |
| 1804 | "session key for authentication token with sig " |
| 1805 | "[%.*s]; rc = [%d]. Removing auth tok " |
| 1806 | "candidate from the list and searching for " |
| 1807 | "the next match.\n", candidate_auth_tok_sig, |
| 1808 | ECRYPTFS_SIG_SIZE_HEX, rc); |
| 1809 | list_for_each_entry_safe(auth_tok_list_item, |
| 1810 | auth_tok_list_item_tmp, |
| 1811 | &auth_tok_list, list) { |
| 1812 | if (candidate_auth_tok |
| 1813 | == &auth_tok_list_item->auth_tok) { |
| 1814 | list_del(&auth_tok_list_item->list); |
| 1815 | kmem_cache_free( |
| 1816 | ecryptfs_auth_tok_list_item_cache, |
| 1817 | auth_tok_list_item); |
| 1818 | goto find_next_matching_auth_tok; |
| 1819 | } |
| 1820 | } |
| 1821 | BUG(); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1822 | } |
| 1823 | rc = ecryptfs_compute_root_iv(crypt_stat); |
| 1824 | if (rc) { |
| 1825 | ecryptfs_printk(KERN_ERR, "Error computing " |
| 1826 | "the root IV\n"); |
| 1827 | goto out_wipe_list; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1828 | } |
| 1829 | rc = ecryptfs_init_crypt_ctx(crypt_stat); |
| 1830 | if (rc) { |
| 1831 | ecryptfs_printk(KERN_ERR, "Error initializing crypto " |
| 1832 | "context for cipher [%s]; rc = [%d]\n", |
| 1833 | crypt_stat->cipher, rc); |
| 1834 | } |
| 1835 | out_wipe_list: |
| 1836 | wipe_auth_tok_list(&auth_tok_list); |
| 1837 | out: |
| 1838 | return rc; |
| 1839 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1840 | |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1841 | static int |
| 1842 | pki_encrypt_session_key(struct ecryptfs_auth_tok *auth_tok, |
| 1843 | struct ecryptfs_crypt_stat *crypt_stat, |
| 1844 | struct ecryptfs_key_record *key_rec) |
| 1845 | { |
| 1846 | struct ecryptfs_msg_ctx *msg_ctx = NULL; |
Tyler Hicks | 624ae52 | 2008-10-15 22:02:51 -0700 | [diff] [blame] | 1847 | char *payload = NULL; |
| 1848 | size_t payload_len; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1849 | struct ecryptfs_message *msg; |
| 1850 | int rc; |
| 1851 | |
| 1852 | rc = write_tag_66_packet(auth_tok->token.private_key.signature, |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 1853 | ecryptfs_code_for_cipher_string( |
| 1854 | crypt_stat->cipher, |
| 1855 | crypt_stat->key_size), |
Tyler Hicks | 624ae52 | 2008-10-15 22:02:51 -0700 | [diff] [blame] | 1856 | crypt_stat, &payload, &payload_len); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1857 | if (rc) { |
| 1858 | ecryptfs_printk(KERN_ERR, "Error generating tag 66 packet\n"); |
| 1859 | goto out; |
| 1860 | } |
Tyler Hicks | 624ae52 | 2008-10-15 22:02:51 -0700 | [diff] [blame] | 1861 | rc = ecryptfs_send_message(payload, payload_len, &msg_ctx); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1862 | if (rc) { |
Tyler Hicks | 624ae52 | 2008-10-15 22:02:51 -0700 | [diff] [blame] | 1863 | ecryptfs_printk(KERN_ERR, "Error sending message to " |
| 1864 | "ecryptfsd\n"); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1865 | goto out; |
| 1866 | } |
| 1867 | rc = ecryptfs_wait_for_response(msg_ctx, &msg); |
| 1868 | if (rc) { |
| 1869 | ecryptfs_printk(KERN_ERR, "Failed to receive tag 67 packet " |
| 1870 | "from the user space daemon\n"); |
| 1871 | rc = -EIO; |
| 1872 | goto out; |
| 1873 | } |
| 1874 | rc = parse_tag_67_packet(key_rec, msg); |
| 1875 | if (rc) |
| 1876 | ecryptfs_printk(KERN_ERR, "Error parsing tag 67 packet\n"); |
| 1877 | kfree(msg); |
| 1878 | out: |
Tyler Hicks | 624ae52 | 2008-10-15 22:02:51 -0700 | [diff] [blame] | 1879 | kfree(payload); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1880 | return rc; |
| 1881 | } |
| 1882 | /** |
| 1883 | * write_tag_1_packet - Write an RFC2440-compatible tag 1 (public key) packet |
| 1884 | * @dest: Buffer into which to write the packet |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1885 | * @remaining_bytes: Maximum number of bytes that can be writtn |
| 1886 | * @auth_tok: The authentication token used for generating the tag 1 packet |
| 1887 | * @crypt_stat: The cryptographic context |
| 1888 | * @key_rec: The key record struct for the tag 1 packet |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1889 | * @packet_size: This function will write the number of bytes that end |
| 1890 | * up constituting the packet; set to zero on error |
| 1891 | * |
| 1892 | * Returns zero on success; non-zero on error. |
| 1893 | */ |
| 1894 | static int |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1895 | write_tag_1_packet(char *dest, size_t *remaining_bytes, |
| 1896 | struct ecryptfs_auth_tok *auth_tok, |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1897 | struct ecryptfs_crypt_stat *crypt_stat, |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1898 | struct ecryptfs_key_record *key_rec, size_t *packet_size) |
| 1899 | { |
| 1900 | size_t i; |
| 1901 | size_t encrypted_session_key_valid = 0; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1902 | size_t packet_size_length; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1903 | size_t max_packet_size; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1904 | int rc = 0; |
| 1905 | |
| 1906 | (*packet_size) = 0; |
| 1907 | ecryptfs_from_hex(key_rec->sig, auth_tok->token.private_key.signature, |
| 1908 | ECRYPTFS_SIG_SIZE); |
| 1909 | encrypted_session_key_valid = 0; |
| 1910 | for (i = 0; i < crypt_stat->key_size; i++) |
| 1911 | encrypted_session_key_valid |= |
| 1912 | auth_tok->session_key.encrypted_key[i]; |
| 1913 | if (encrypted_session_key_valid) { |
| 1914 | memcpy(key_rec->enc_key, |
| 1915 | auth_tok->session_key.encrypted_key, |
| 1916 | auth_tok->session_key.encrypted_key_size); |
| 1917 | goto encrypted_session_key_set; |
| 1918 | } |
| 1919 | if (auth_tok->session_key.encrypted_key_size == 0) |
| 1920 | auth_tok->session_key.encrypted_key_size = |
| 1921 | auth_tok->token.private_key.key_size; |
| 1922 | rc = pki_encrypt_session_key(auth_tok, crypt_stat, key_rec); |
| 1923 | if (rc) { |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 1924 | printk(KERN_ERR "Failed to encrypt session key via a key " |
| 1925 | "module; rc = [%d]\n", rc); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1926 | goto out; |
| 1927 | } |
| 1928 | if (ecryptfs_verbosity > 0) { |
| 1929 | ecryptfs_printk(KERN_DEBUG, "Encrypted key:\n"); |
| 1930 | ecryptfs_dump_hex(key_rec->enc_key, key_rec->enc_key_size); |
| 1931 | } |
| 1932 | encrypted_session_key_set: |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1933 | /* This format is inspired by OpenPGP; see RFC 2440 |
| 1934 | * packet tag 1 */ |
| 1935 | max_packet_size = (1 /* Tag 1 identifier */ |
| 1936 | + 3 /* Max Tag 1 packet size */ |
| 1937 | + 1 /* Version */ |
| 1938 | + ECRYPTFS_SIG_SIZE /* Key identifier */ |
| 1939 | + 1 /* Cipher identifier */ |
| 1940 | + key_rec->enc_key_size); /* Encrypted key size */ |
| 1941 | if (max_packet_size > (*remaining_bytes)) { |
| 1942 | printk(KERN_ERR "Packet length larger than maximum allowable; " |
Andrew Morton | 81acbcd | 2007-10-16 01:27:59 -0700 | [diff] [blame] | 1943 | "need up to [%td] bytes, but there are only [%td] " |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1944 | "available\n", max_packet_size, (*remaining_bytes)); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1945 | rc = -EINVAL; |
| 1946 | goto out; |
| 1947 | } |
| 1948 | dest[(*packet_size)++] = ECRYPTFS_TAG_1_PACKET_TYPE; |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 1949 | rc = ecryptfs_write_packet_length(&dest[(*packet_size)], |
| 1950 | (max_packet_size - 4), |
| 1951 | &packet_size_length); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1952 | if (rc) { |
| 1953 | ecryptfs_printk(KERN_ERR, "Error generating tag 1 packet " |
| 1954 | "header; cannot generate packet length\n"); |
| 1955 | goto out; |
| 1956 | } |
| 1957 | (*packet_size) += packet_size_length; |
| 1958 | dest[(*packet_size)++] = 0x03; /* version 3 */ |
| 1959 | memcpy(&dest[(*packet_size)], key_rec->sig, ECRYPTFS_SIG_SIZE); |
| 1960 | (*packet_size) += ECRYPTFS_SIG_SIZE; |
| 1961 | dest[(*packet_size)++] = RFC2440_CIPHER_RSA; |
| 1962 | memcpy(&dest[(*packet_size)], key_rec->enc_key, |
| 1963 | key_rec->enc_key_size); |
| 1964 | (*packet_size) += key_rec->enc_key_size; |
| 1965 | out: |
| 1966 | if (rc) |
| 1967 | (*packet_size) = 0; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 1968 | else |
| 1969 | (*remaining_bytes) -= (*packet_size); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1970 | return rc; |
| 1971 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1972 | |
| 1973 | /** |
| 1974 | * write_tag_11_packet |
| 1975 | * @dest: Target into which Tag 11 packet is to be written |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 1976 | * @remaining_bytes: Maximum packet length |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1977 | * @contents: Byte array of contents to copy in |
| 1978 | * @contents_length: Number of bytes in contents |
| 1979 | * @packet_length: Length of the Tag 11 packet written; zero on error |
| 1980 | * |
| 1981 | * Returns zero on success; non-zero on error. |
| 1982 | */ |
| 1983 | static int |
Andrew Morton | 81acbcd | 2007-10-16 01:27:59 -0700 | [diff] [blame] | 1984 | write_tag_11_packet(char *dest, size_t *remaining_bytes, char *contents, |
Michael Halcrow | 146a460 | 2007-10-16 01:27:58 -0700 | [diff] [blame] | 1985 | size_t contents_length, size_t *packet_length) |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1986 | { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1987 | size_t packet_size_length; |
Michael Halcrow | 146a460 | 2007-10-16 01:27:58 -0700 | [diff] [blame] | 1988 | size_t max_packet_size; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 1989 | int rc = 0; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 1990 | |
| 1991 | (*packet_length) = 0; |
Michael Halcrow | 146a460 | 2007-10-16 01:27:58 -0700 | [diff] [blame] | 1992 | /* This format is inspired by OpenPGP; see RFC 2440 |
| 1993 | * packet tag 11 */ |
| 1994 | max_packet_size = (1 /* Tag 11 identifier */ |
| 1995 | + 3 /* Max Tag 11 packet size */ |
| 1996 | + 1 /* Binary format specifier */ |
| 1997 | + 1 /* Filename length */ |
| 1998 | + 8 /* Filename ("_CONSOLE") */ |
| 1999 | + 4 /* Modification date */ |
| 2000 | + contents_length); /* Literal data */ |
| 2001 | if (max_packet_size > (*remaining_bytes)) { |
| 2002 | printk(KERN_ERR "Packet length larger than maximum allowable; " |
Andrew Morton | 81acbcd | 2007-10-16 01:27:59 -0700 | [diff] [blame] | 2003 | "need up to [%td] bytes, but there are only [%td] " |
Michael Halcrow | 146a460 | 2007-10-16 01:27:58 -0700 | [diff] [blame] | 2004 | "available\n", max_packet_size, (*remaining_bytes)); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2005 | rc = -EINVAL; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2006 | goto out; |
| 2007 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2008 | dest[(*packet_length)++] = ECRYPTFS_TAG_11_PACKET_TYPE; |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 2009 | rc = ecryptfs_write_packet_length(&dest[(*packet_length)], |
| 2010 | (max_packet_size - 4), |
| 2011 | &packet_size_length); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2012 | if (rc) { |
Michael Halcrow | 146a460 | 2007-10-16 01:27:58 -0700 | [diff] [blame] | 2013 | printk(KERN_ERR "Error generating tag 11 packet header; cannot " |
| 2014 | "generate packet length. rc = [%d]\n", rc); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2015 | goto out; |
| 2016 | } |
| 2017 | (*packet_length) += packet_size_length; |
Michael Halcrow | 146a460 | 2007-10-16 01:27:58 -0700 | [diff] [blame] | 2018 | dest[(*packet_length)++] = 0x62; /* binary data format specifier */ |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2019 | dest[(*packet_length)++] = 8; |
| 2020 | memcpy(&dest[(*packet_length)], "_CONSOLE", 8); |
| 2021 | (*packet_length) += 8; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2022 | memset(&dest[(*packet_length)], 0x00, 4); |
| 2023 | (*packet_length) += 4; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2024 | memcpy(&dest[(*packet_length)], contents, contents_length); |
| 2025 | (*packet_length) += contents_length; |
| 2026 | out: |
| 2027 | if (rc) |
| 2028 | (*packet_length) = 0; |
Michael Halcrow | 146a460 | 2007-10-16 01:27:58 -0700 | [diff] [blame] | 2029 | else |
| 2030 | (*remaining_bytes) -= (*packet_length); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2031 | return rc; |
| 2032 | } |
| 2033 | |
| 2034 | /** |
| 2035 | * write_tag_3_packet |
| 2036 | * @dest: Buffer into which to write the packet |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 2037 | * @remaining_bytes: Maximum number of bytes that can be written |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2038 | * @auth_tok: Authentication token |
| 2039 | * @crypt_stat: The cryptographic context |
| 2040 | * @key_rec: encrypted key |
| 2041 | * @packet_size: This function will write the number of bytes that end |
| 2042 | * up constituting the packet; set to zero on error |
| 2043 | * |
| 2044 | * Returns zero on success; non-zero on error. |
| 2045 | */ |
| 2046 | static int |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2047 | write_tag_3_packet(char *dest, size_t *remaining_bytes, |
| 2048 | struct ecryptfs_auth_tok *auth_tok, |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2049 | struct ecryptfs_crypt_stat *crypt_stat, |
| 2050 | struct ecryptfs_key_record *key_rec, size_t *packet_size) |
| 2051 | { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2052 | size_t i; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2053 | size_t encrypted_session_key_valid = 0; |
| 2054 | char session_key_encryption_key[ECRYPTFS_MAX_KEY_BYTES]; |
Michael Halcrow | ac97b9f | 2008-11-19 15:36:28 -0800 | [diff] [blame] | 2055 | struct scatterlist dst_sg[2]; |
| 2056 | struct scatterlist src_sg[2]; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2057 | struct mutex *tfm_mutex = NULL; |
Trevor Highland | 19e66a6 | 2008-02-06 01:38:36 -0800 | [diff] [blame] | 2058 | u8 cipher_code; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2059 | size_t packet_size_length; |
| 2060 | size_t max_packet_size; |
| 2061 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat = |
| 2062 | crypt_stat->mount_crypt_stat; |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 2063 | struct blkcipher_desc desc = { |
| 2064 | .tfm = NULL, |
| 2065 | .flags = CRYPTO_TFM_REQ_MAY_SLEEP |
| 2066 | }; |
| 2067 | int rc = 0; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2068 | |
| 2069 | (*packet_size) = 0; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2070 | ecryptfs_from_hex(key_rec->sig, auth_tok->token.password.signature, |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2071 | ECRYPTFS_SIG_SIZE); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2072 | rc = ecryptfs_get_tfm_and_mutex_for_cipher_name(&desc.tfm, &tfm_mutex, |
| 2073 | crypt_stat->cipher); |
| 2074 | if (unlikely(rc)) { |
| 2075 | printk(KERN_ERR "Internal error whilst attempting to get " |
| 2076 | "tfm and mutex for cipher name [%s]; rc = [%d]\n", |
| 2077 | crypt_stat->cipher, rc); |
| 2078 | goto out; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2079 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2080 | if (mount_crypt_stat->global_default_cipher_key_size == 0) { |
| 2081 | struct blkcipher_alg *alg = crypto_blkcipher_alg(desc.tfm); |
| 2082 | |
| 2083 | printk(KERN_WARNING "No key size specified at mount; " |
| 2084 | "defaulting to [%d]\n", alg->max_keysize); |
| 2085 | mount_crypt_stat->global_default_cipher_key_size = |
| 2086 | alg->max_keysize; |
| 2087 | } |
| 2088 | if (crypt_stat->key_size == 0) |
| 2089 | crypt_stat->key_size = |
| 2090 | mount_crypt_stat->global_default_cipher_key_size; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2091 | if (auth_tok->session_key.encrypted_key_size == 0) |
| 2092 | auth_tok->session_key.encrypted_key_size = |
| 2093 | crypt_stat->key_size; |
| 2094 | if (crypt_stat->key_size == 24 |
| 2095 | && strcmp("aes", crypt_stat->cipher) == 0) { |
| 2096 | memset((crypt_stat->key + 24), 0, 8); |
| 2097 | auth_tok->session_key.encrypted_key_size = 32; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2098 | } else |
| 2099 | auth_tok->session_key.encrypted_key_size = crypt_stat->key_size; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2100 | key_rec->enc_key_size = |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2101 | auth_tok->session_key.encrypted_key_size; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2102 | encrypted_session_key_valid = 0; |
| 2103 | for (i = 0; i < auth_tok->session_key.encrypted_key_size; i++) |
| 2104 | encrypted_session_key_valid |= |
| 2105 | auth_tok->session_key.encrypted_key[i]; |
| 2106 | if (encrypted_session_key_valid) { |
| 2107 | ecryptfs_printk(KERN_DEBUG, "encrypted_session_key_valid != 0; " |
| 2108 | "using auth_tok->session_key.encrypted_key, " |
| 2109 | "where key_rec->enc_key_size = [%d]\n", |
| 2110 | key_rec->enc_key_size); |
| 2111 | memcpy(key_rec->enc_key, |
| 2112 | auth_tok->session_key.encrypted_key, |
| 2113 | key_rec->enc_key_size); |
| 2114 | goto encrypted_session_key_set; |
| 2115 | } |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2116 | if (auth_tok->token.password.flags & |
| 2117 | ECRYPTFS_SESSION_KEY_ENCRYPTION_KEY_SET) { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2118 | ecryptfs_printk(KERN_DEBUG, "Using previously generated " |
| 2119 | "session key encryption key of size [%d]\n", |
| 2120 | auth_tok->token.password. |
| 2121 | session_key_encryption_key_bytes); |
| 2122 | memcpy(session_key_encryption_key, |
| 2123 | auth_tok->token.password.session_key_encryption_key, |
| 2124 | crypt_stat->key_size); |
| 2125 | ecryptfs_printk(KERN_DEBUG, |
| 2126 | "Cached session key " "encryption key: \n"); |
| 2127 | if (ecryptfs_verbosity > 0) |
| 2128 | ecryptfs_dump_hex(session_key_encryption_key, 16); |
| 2129 | } |
| 2130 | if (unlikely(ecryptfs_verbosity > 0)) { |
| 2131 | ecryptfs_printk(KERN_DEBUG, "Session key encryption key:\n"); |
| 2132 | ecryptfs_dump_hex(session_key_encryption_key, 16); |
| 2133 | } |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 2134 | rc = virt_to_scatterlist(crypt_stat->key, key_rec->enc_key_size, |
Michael Halcrow | ac97b9f | 2008-11-19 15:36:28 -0800 | [diff] [blame] | 2135 | src_sg, 2); |
| 2136 | if (rc < 1 || rc > 2) { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2137 | ecryptfs_printk(KERN_ERR, "Error generating scatterlist " |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2138 | "for crypt_stat session key; expected rc = 1; " |
| 2139 | "got rc = [%d]. key_rec->enc_key_size = [%d]\n", |
| 2140 | rc, key_rec->enc_key_size); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2141 | rc = -ENOMEM; |
| 2142 | goto out; |
| 2143 | } |
Michael Halcrow | 5dda699 | 2007-10-16 01:28:06 -0700 | [diff] [blame] | 2144 | 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] | 2145 | dst_sg, 2); |
| 2146 | if (rc < 1 || rc > 2) { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2147 | ecryptfs_printk(KERN_ERR, "Error generating scatterlist " |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2148 | "for crypt_stat encrypted session key; " |
| 2149 | "expected rc = 1; got rc = [%d]. " |
| 2150 | "key_rec->enc_key_size = [%d]\n", rc, |
| 2151 | key_rec->enc_key_size); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2152 | rc = -ENOMEM; |
| 2153 | goto out; |
| 2154 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2155 | mutex_lock(tfm_mutex); |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 2156 | rc = crypto_blkcipher_setkey(desc.tfm, session_key_encryption_key, |
| 2157 | crypt_stat->key_size); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2158 | if (rc < 0) { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2159 | mutex_unlock(tfm_mutex); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2160 | ecryptfs_printk(KERN_ERR, "Error setting key for crypto " |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 2161 | "context; rc = [%d]\n", rc); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2162 | goto out; |
| 2163 | } |
| 2164 | rc = 0; |
| 2165 | ecryptfs_printk(KERN_DEBUG, "Encrypting [%d] bytes of the key\n", |
| 2166 | crypt_stat->key_size); |
Michael Halcrow | ac97b9f | 2008-11-19 15:36:28 -0800 | [diff] [blame] | 2167 | rc = crypto_blkcipher_encrypt(&desc, dst_sg, src_sg, |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 2168 | (*key_rec).enc_key_size); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2169 | mutex_unlock(tfm_mutex); |
Michael Halcrow | 8bba066 | 2006-10-30 22:07:18 -0800 | [diff] [blame] | 2170 | if (rc) { |
| 2171 | printk(KERN_ERR "Error encrypting; rc = [%d]\n", rc); |
| 2172 | goto out; |
| 2173 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2174 | ecryptfs_printk(KERN_DEBUG, "This should be the encrypted key:\n"); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2175 | if (ecryptfs_verbosity > 0) { |
| 2176 | ecryptfs_printk(KERN_DEBUG, "EFEK of size [%d]:\n", |
| 2177 | key_rec->enc_key_size); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2178 | ecryptfs_dump_hex(key_rec->enc_key, |
| 2179 | key_rec->enc_key_size); |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2180 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2181 | encrypted_session_key_set: |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2182 | /* This format is inspired by OpenPGP; see RFC 2440 |
| 2183 | * packet tag 3 */ |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2184 | max_packet_size = (1 /* Tag 3 identifier */ |
| 2185 | + 3 /* Max Tag 3 packet size */ |
| 2186 | + 1 /* Version */ |
| 2187 | + 1 /* Cipher code */ |
| 2188 | + 1 /* S2K specifier */ |
| 2189 | + 1 /* Hash identifier */ |
| 2190 | + ECRYPTFS_SALT_SIZE /* Salt */ |
| 2191 | + 1 /* Hash iterations */ |
| 2192 | + key_rec->enc_key_size); /* Encrypted key size */ |
| 2193 | if (max_packet_size > (*remaining_bytes)) { |
Andrew Morton | 81acbcd | 2007-10-16 01:27:59 -0700 | [diff] [blame] | 2194 | printk(KERN_ERR "Packet too large; need up to [%td] bytes, but " |
| 2195 | "there are only [%td] available\n", max_packet_size, |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2196 | (*remaining_bytes)); |
| 2197 | rc = -EINVAL; |
| 2198 | goto out; |
| 2199 | } |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2200 | dest[(*packet_size)++] = ECRYPTFS_TAG_3_PACKET_TYPE; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2201 | /* Chop off the Tag 3 identifier(1) and Tag 3 packet size(3) |
| 2202 | * to get the number of octets in the actual Tag 3 packet */ |
Michael Halcrow | f66e883 | 2008-04-29 00:59:51 -0700 | [diff] [blame] | 2203 | rc = ecryptfs_write_packet_length(&dest[(*packet_size)], |
| 2204 | (max_packet_size - 4), |
| 2205 | &packet_size_length); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2206 | if (rc) { |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2207 | printk(KERN_ERR "Error generating tag 3 packet header; cannot " |
| 2208 | "generate packet length. rc = [%d]\n", rc); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2209 | goto out; |
| 2210 | } |
| 2211 | (*packet_size) += packet_size_length; |
| 2212 | dest[(*packet_size)++] = 0x04; /* version 4 */ |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2213 | /* TODO: Break from RFC2440 so that arbitrary ciphers can be |
| 2214 | * specified with strings */ |
Michael Halcrow | 9c79f34 | 2009-01-06 14:41:57 -0800 | [diff] [blame] | 2215 | cipher_code = ecryptfs_code_for_cipher_string(crypt_stat->cipher, |
| 2216 | crypt_stat->key_size); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2217 | if (cipher_code == 0) { |
| 2218 | ecryptfs_printk(KERN_WARNING, "Unable to generate code for " |
| 2219 | "cipher [%s]\n", crypt_stat->cipher); |
| 2220 | rc = -EINVAL; |
| 2221 | goto out; |
| 2222 | } |
| 2223 | dest[(*packet_size)++] = cipher_code; |
| 2224 | dest[(*packet_size)++] = 0x03; /* S2K */ |
| 2225 | dest[(*packet_size)++] = 0x01; /* MD5 (TODO: parameterize) */ |
| 2226 | memcpy(&dest[(*packet_size)], auth_tok->token.password.salt, |
| 2227 | ECRYPTFS_SALT_SIZE); |
| 2228 | (*packet_size) += ECRYPTFS_SALT_SIZE; /* salt */ |
| 2229 | dest[(*packet_size)++] = 0x60; /* hash iterations (65536) */ |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2230 | memcpy(&dest[(*packet_size)], key_rec->enc_key, |
| 2231 | key_rec->enc_key_size); |
| 2232 | (*packet_size) += key_rec->enc_key_size; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2233 | out: |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2234 | if (rc) |
| 2235 | (*packet_size) = 0; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2236 | else |
| 2237 | (*remaining_bytes) -= (*packet_size); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2238 | return rc; |
| 2239 | } |
| 2240 | |
Michael Halcrow | eb95e7f | 2007-02-16 01:28:40 -0800 | [diff] [blame] | 2241 | struct kmem_cache *ecryptfs_key_record_cache; |
| 2242 | |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2243 | /** |
| 2244 | * ecryptfs_generate_key_packet_set |
Michael Halcrow | 22e78fa | 2007-10-16 01:28:02 -0700 | [diff] [blame] | 2245 | * @dest_base: Virtual address from which to write the key record set |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2246 | * @crypt_stat: The cryptographic context from which the |
| 2247 | * authentication tokens will be retrieved |
| 2248 | * @ecryptfs_dentry: The dentry, used to retrieve the mount crypt stat |
| 2249 | * for the global parameters |
| 2250 | * @len: The amount written |
| 2251 | * @max: The maximum amount of data allowed to be written |
| 2252 | * |
| 2253 | * Generates a key packet set and writes it to the virtual address |
| 2254 | * passed in. |
| 2255 | * |
| 2256 | * Returns zero on success; non-zero on error. |
| 2257 | */ |
| 2258 | int |
| 2259 | ecryptfs_generate_key_packet_set(char *dest_base, |
| 2260 | struct ecryptfs_crypt_stat *crypt_stat, |
| 2261 | struct dentry *ecryptfs_dentry, size_t *len, |
| 2262 | size_t max) |
| 2263 | { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2264 | struct ecryptfs_auth_tok *auth_tok; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2265 | struct ecryptfs_global_auth_tok *global_auth_tok; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2266 | struct ecryptfs_mount_crypt_stat *mount_crypt_stat = |
| 2267 | &ecryptfs_superblock_to_private( |
| 2268 | ecryptfs_dentry->d_sb)->mount_crypt_stat; |
| 2269 | size_t written; |
Michael Halcrow | eb95e7f | 2007-02-16 01:28:40 -0800 | [diff] [blame] | 2270 | struct ecryptfs_key_record *key_rec; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2271 | struct ecryptfs_key_sig *key_sig; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2272 | int rc = 0; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2273 | |
| 2274 | (*len) = 0; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2275 | mutex_lock(&crypt_stat->keysig_list_mutex); |
Michael Halcrow | eb95e7f | 2007-02-16 01:28:40 -0800 | [diff] [blame] | 2276 | key_rec = kmem_cache_alloc(ecryptfs_key_record_cache, GFP_KERNEL); |
| 2277 | if (!key_rec) { |
| 2278 | rc = -ENOMEM; |
| 2279 | goto out; |
| 2280 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2281 | list_for_each_entry(key_sig, &crypt_stat->keysig_list, |
| 2282 | crypt_stat_list) { |
| 2283 | memset(key_rec, 0, sizeof(*key_rec)); |
| 2284 | rc = ecryptfs_find_global_auth_tok_for_sig(&global_auth_tok, |
| 2285 | mount_crypt_stat, |
| 2286 | key_sig->keysig); |
| 2287 | if (rc) { |
| 2288 | printk(KERN_ERR "Error attempting to get the global " |
| 2289 | "auth_tok; rc = [%d]\n", rc); |
| 2290 | goto out_free; |
| 2291 | } |
| 2292 | if (global_auth_tok->flags & ECRYPTFS_AUTH_TOK_INVALID) { |
| 2293 | printk(KERN_WARNING |
| 2294 | "Skipping invalid auth tok with sig = [%s]\n", |
| 2295 | global_auth_tok->sig); |
| 2296 | continue; |
| 2297 | } |
| 2298 | auth_tok = global_auth_tok->global_auth_tok; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2299 | if (auth_tok->token_type == ECRYPTFS_PASSWORD) { |
| 2300 | rc = write_tag_3_packet((dest_base + (*len)), |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2301 | &max, auth_tok, |
Michael Halcrow | eb95e7f | 2007-02-16 01:28:40 -0800 | [diff] [blame] | 2302 | crypt_stat, key_rec, |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2303 | &written); |
| 2304 | if (rc) { |
| 2305 | ecryptfs_printk(KERN_WARNING, "Error " |
| 2306 | "writing tag 3 packet\n"); |
Michael Halcrow | eb95e7f | 2007-02-16 01:28:40 -0800 | [diff] [blame] | 2307 | goto out_free; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2308 | } |
| 2309 | (*len) += written; |
| 2310 | /* Write auth tok signature packet */ |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2311 | rc = write_tag_11_packet((dest_base + (*len)), &max, |
| 2312 | key_rec->sig, |
| 2313 | ECRYPTFS_SIG_SIZE, &written); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2314 | if (rc) { |
| 2315 | ecryptfs_printk(KERN_ERR, "Error writing " |
| 2316 | "auth tok signature packet\n"); |
Michael Halcrow | eb95e7f | 2007-02-16 01:28:40 -0800 | [diff] [blame] | 2317 | goto out_free; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2318 | } |
| 2319 | (*len) += written; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2320 | } else if (auth_tok->token_type == ECRYPTFS_PRIVATE_KEY) { |
| 2321 | rc = write_tag_1_packet(dest_base + (*len), |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2322 | &max, auth_tok, |
| 2323 | crypt_stat, key_rec, &written); |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2324 | if (rc) { |
| 2325 | ecryptfs_printk(KERN_WARNING, "Error " |
| 2326 | "writing tag 1 packet\n"); |
Michael Halcrow | eb95e7f | 2007-02-16 01:28:40 -0800 | [diff] [blame] | 2327 | goto out_free; |
Michael Halcrow | dddfa46 | 2007-02-12 00:53:44 -0800 | [diff] [blame] | 2328 | } |
| 2329 | (*len) += written; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2330 | } else { |
| 2331 | ecryptfs_printk(KERN_WARNING, "Unsupported " |
| 2332 | "authentication token type\n"); |
| 2333 | rc = -EINVAL; |
Michael Halcrow | eb95e7f | 2007-02-16 01:28:40 -0800 | [diff] [blame] | 2334 | goto out_free; |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2335 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2336 | } |
| 2337 | if (likely(max > 0)) { |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2338 | dest_base[(*len)] = 0x00; |
| 2339 | } else { |
| 2340 | ecryptfs_printk(KERN_ERR, "Error writing boundary byte\n"); |
| 2341 | rc = -EIO; |
| 2342 | } |
Michael Halcrow | eb95e7f | 2007-02-16 01:28:40 -0800 | [diff] [blame] | 2343 | out_free: |
| 2344 | kmem_cache_free(ecryptfs_key_record_cache, key_rec); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2345 | out: |
| 2346 | if (rc) |
| 2347 | (*len) = 0; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2348 | mutex_unlock(&crypt_stat->keysig_list_mutex); |
Michael Halcrow | 237fead | 2006-10-04 02:16:22 -0700 | [diff] [blame] | 2349 | return rc; |
| 2350 | } |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2351 | |
| 2352 | struct kmem_cache *ecryptfs_key_sig_cache; |
| 2353 | |
| 2354 | int ecryptfs_add_keysig(struct ecryptfs_crypt_stat *crypt_stat, char *sig) |
| 2355 | { |
| 2356 | struct ecryptfs_key_sig *new_key_sig; |
| 2357 | int rc = 0; |
| 2358 | |
| 2359 | new_key_sig = kmem_cache_alloc(ecryptfs_key_sig_cache, GFP_KERNEL); |
| 2360 | if (!new_key_sig) { |
| 2361 | rc = -ENOMEM; |
| 2362 | printk(KERN_ERR |
| 2363 | "Error allocating from ecryptfs_key_sig_cache\n"); |
| 2364 | goto out; |
| 2365 | } |
| 2366 | memcpy(new_key_sig->keysig, sig, ECRYPTFS_SIG_SIZE_HEX); |
| 2367 | mutex_lock(&crypt_stat->keysig_list_mutex); |
| 2368 | list_add(&new_key_sig->crypt_stat_list, &crypt_stat->keysig_list); |
| 2369 | mutex_unlock(&crypt_stat->keysig_list_mutex); |
| 2370 | out: |
| 2371 | return rc; |
| 2372 | } |
| 2373 | |
| 2374 | struct kmem_cache *ecryptfs_global_auth_tok_cache; |
| 2375 | |
| 2376 | int |
| 2377 | 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^] | 2378 | char *sig, u32 global_auth_tok_flags) |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2379 | { |
| 2380 | struct ecryptfs_global_auth_tok *new_auth_tok; |
| 2381 | int rc = 0; |
| 2382 | |
Eric Sandeen | 459e216 | 2007-12-17 16:19:52 -0800 | [diff] [blame] | 2383 | new_auth_tok = kmem_cache_zalloc(ecryptfs_global_auth_tok_cache, |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2384 | GFP_KERNEL); |
| 2385 | if (!new_auth_tok) { |
| 2386 | rc = -ENOMEM; |
| 2387 | printk(KERN_ERR "Error allocating from " |
| 2388 | "ecryptfs_global_auth_tok_cache\n"); |
| 2389 | goto out; |
| 2390 | } |
| 2391 | memcpy(new_auth_tok->sig, sig, ECRYPTFS_SIG_SIZE_HEX); |
Tyler Hicks | 84814d6 | 2009-03-13 13:51:59 -0700 | [diff] [blame^] | 2392 | new_auth_tok->flags = global_auth_tok_flags; |
Michael Halcrow | f4aad16 | 2007-10-16 01:27:53 -0700 | [diff] [blame] | 2393 | new_auth_tok->sig[ECRYPTFS_SIG_SIZE_HEX] = '\0'; |
| 2394 | mutex_lock(&mount_crypt_stat->global_auth_tok_list_mutex); |
| 2395 | list_add(&new_auth_tok->mount_crypt_stat_list, |
| 2396 | &mount_crypt_stat->global_auth_tok_list); |
| 2397 | mount_crypt_stat->num_global_auth_toks++; |
| 2398 | mutex_unlock(&mount_crypt_stat->global_auth_tok_list_mutex); |
| 2399 | out: |
| 2400 | return rc; |
| 2401 | } |
| 2402 | |