David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 1 | /* X.509 certificate parser |
| 2 | * |
| 3 | * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. |
| 4 | * Written by David Howells (dhowells@redhat.com) |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU General Public Licence |
| 8 | * as published by the Free Software Foundation; either version |
| 9 | * 2 of the Licence, or (at your option) any later version. |
| 10 | */ |
| 11 | |
| 12 | #define pr_fmt(fmt) "X.509: "fmt |
| 13 | #include <linux/kernel.h> |
David Howells | ace0107 | 2014-07-01 16:40:19 +0100 | [diff] [blame] | 14 | #include <linux/export.h> |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 15 | #include <linux/slab.h> |
| 16 | #include <linux/err.h> |
| 17 | #include <linux/oid_registry.h> |
| 18 | #include "public_key.h" |
| 19 | #include "x509_parser.h" |
| 20 | #include "x509-asn1.h" |
David Howells | b92e657 | 2015-07-20 21:16:26 +0100 | [diff] [blame] | 21 | #include "x509_akid-asn1.h" |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 22 | #include "x509_rsakey-asn1.h" |
| 23 | |
| 24 | struct x509_parse_context { |
| 25 | struct x509_certificate *cert; /* Certificate being constructed */ |
| 26 | unsigned long data; /* Start of data */ |
| 27 | const void *cert_start; /* Start of cert content */ |
| 28 | const void *key; /* Key data */ |
| 29 | size_t key_size; /* Size of key data */ |
| 30 | enum OID last_oid; /* Last OID encountered */ |
| 31 | enum OID algo_oid; /* Algorithm OID */ |
| 32 | unsigned char nr_mpi; /* Number of MPIs stored */ |
| 33 | u8 o_size; /* Size of organizationName (O) */ |
| 34 | u8 cn_size; /* Size of commonName (CN) */ |
| 35 | u8 email_size; /* Size of emailAddress */ |
| 36 | u16 o_offset; /* Offset of organizationName (O) */ |
| 37 | u16 cn_offset; /* Offset of commonName (CN) */ |
| 38 | u16 email_offset; /* Offset of emailAddress */ |
David Howells | b92e657 | 2015-07-20 21:16:26 +0100 | [diff] [blame] | 39 | unsigned raw_akid_size; |
| 40 | const void *raw_akid; /* Raw authorityKeyId in ASN.1 */ |
| 41 | const void *akid_raw_issuer; /* Raw directoryName in authorityKeyId */ |
| 42 | unsigned akid_raw_issuer_size; |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 43 | }; |
| 44 | |
| 45 | /* |
| 46 | * Free an X.509 certificate |
| 47 | */ |
| 48 | void x509_free_certificate(struct x509_certificate *cert) |
| 49 | { |
| 50 | if (cert) { |
| 51 | public_key_destroy(cert->pub); |
| 52 | kfree(cert->issuer); |
| 53 | kfree(cert->subject); |
David Howells | 46963b7 | 2014-09-16 17:36:13 +0100 | [diff] [blame] | 54 | kfree(cert->id); |
| 55 | kfree(cert->skid); |
David Howells | b92e657 | 2015-07-20 21:16:26 +0100 | [diff] [blame] | 56 | kfree(cert->akid_id); |
| 57 | kfree(cert->akid_skid); |
David Howells | b426beb | 2013-08-30 16:18:02 +0100 | [diff] [blame] | 58 | kfree(cert->sig.digest); |
| 59 | mpi_free(cert->sig.rsa.s); |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 60 | kfree(cert); |
| 61 | } |
| 62 | } |
David Howells | ace0107 | 2014-07-01 16:40:19 +0100 | [diff] [blame] | 63 | EXPORT_SYMBOL_GPL(x509_free_certificate); |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 64 | |
| 65 | /* |
| 66 | * Parse an X.509 certificate |
| 67 | */ |
| 68 | struct x509_certificate *x509_cert_parse(const void *data, size_t datalen) |
| 69 | { |
| 70 | struct x509_certificate *cert; |
| 71 | struct x509_parse_context *ctx; |
David Howells | 46963b7 | 2014-09-16 17:36:13 +0100 | [diff] [blame] | 72 | struct asymmetric_key_id *kid; |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 73 | long ret; |
| 74 | |
| 75 | ret = -ENOMEM; |
| 76 | cert = kzalloc(sizeof(struct x509_certificate), GFP_KERNEL); |
| 77 | if (!cert) |
| 78 | goto error_no_cert; |
| 79 | cert->pub = kzalloc(sizeof(struct public_key), GFP_KERNEL); |
| 80 | if (!cert->pub) |
| 81 | goto error_no_ctx; |
| 82 | ctx = kzalloc(sizeof(struct x509_parse_context), GFP_KERNEL); |
| 83 | if (!ctx) |
| 84 | goto error_no_ctx; |
| 85 | |
| 86 | ctx->cert = cert; |
| 87 | ctx->data = (unsigned long)data; |
| 88 | |
| 89 | /* Attempt to decode the certificate */ |
| 90 | ret = asn1_ber_decoder(&x509_decoder, ctx, data, datalen); |
| 91 | if (ret < 0) |
| 92 | goto error_decode; |
| 93 | |
David Howells | b92e657 | 2015-07-20 21:16:26 +0100 | [diff] [blame] | 94 | /* Decode the AuthorityKeyIdentifier */ |
| 95 | if (ctx->raw_akid) { |
| 96 | pr_devel("AKID: %u %*phN\n", |
| 97 | ctx->raw_akid_size, ctx->raw_akid_size, ctx->raw_akid); |
| 98 | ret = asn1_ber_decoder(&x509_akid_decoder, ctx, |
| 99 | ctx->raw_akid, ctx->raw_akid_size); |
| 100 | if (ret < 0) { |
| 101 | pr_warn("Couldn't decode AuthKeyIdentifier\n"); |
| 102 | goto error_decode; |
| 103 | } |
| 104 | } |
| 105 | |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 106 | /* Decode the public key */ |
| 107 | ret = asn1_ber_decoder(&x509_rsakey_decoder, ctx, |
| 108 | ctx->key, ctx->key_size); |
| 109 | if (ret < 0) |
| 110 | goto error_decode; |
| 111 | |
David Howells | 46963b7 | 2014-09-16 17:36:13 +0100 | [diff] [blame] | 112 | /* Generate cert issuer + serial number key ID */ |
| 113 | kid = asymmetric_key_generate_id(cert->raw_serial, |
| 114 | cert->raw_serial_size, |
| 115 | cert->raw_issuer, |
| 116 | cert->raw_issuer_size); |
| 117 | if (IS_ERR(kid)) { |
| 118 | ret = PTR_ERR(kid); |
| 119 | goto error_decode; |
| 120 | } |
| 121 | cert->id = kid; |
| 122 | |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 123 | kfree(ctx); |
| 124 | return cert; |
| 125 | |
| 126 | error_decode: |
| 127 | kfree(ctx); |
| 128 | error_no_ctx: |
| 129 | x509_free_certificate(cert); |
| 130 | error_no_cert: |
| 131 | return ERR_PTR(ret); |
| 132 | } |
David Howells | ace0107 | 2014-07-01 16:40:19 +0100 | [diff] [blame] | 133 | EXPORT_SYMBOL_GPL(x509_cert_parse); |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 134 | |
| 135 | /* |
| 136 | * Note an OID when we find one for later processing when we know how |
| 137 | * to interpret it. |
| 138 | */ |
| 139 | int x509_note_OID(void *context, size_t hdrlen, |
| 140 | unsigned char tag, |
| 141 | const void *value, size_t vlen) |
| 142 | { |
| 143 | struct x509_parse_context *ctx = context; |
| 144 | |
| 145 | ctx->last_oid = look_up_OID(value, vlen); |
| 146 | if (ctx->last_oid == OID__NR) { |
| 147 | char buffer[50]; |
| 148 | sprint_oid(value, vlen, buffer, sizeof(buffer)); |
Randy Dunlap | cf75446 | 2012-10-03 16:04:46 -0700 | [diff] [blame] | 149 | pr_debug("Unknown OID: [%lu] %s\n", |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 150 | (unsigned long)value - ctx->data, buffer); |
| 151 | } |
| 152 | return 0; |
| 153 | } |
| 154 | |
| 155 | /* |
| 156 | * Save the position of the TBS data so that we can check the signature over it |
| 157 | * later. |
| 158 | */ |
| 159 | int x509_note_tbs_certificate(void *context, size_t hdrlen, |
| 160 | unsigned char tag, |
| 161 | const void *value, size_t vlen) |
| 162 | { |
| 163 | struct x509_parse_context *ctx = context; |
| 164 | |
| 165 | pr_debug("x509_note_tbs_certificate(,%zu,%02x,%ld,%zu)!\n", |
| 166 | hdrlen, tag, (unsigned long)value - ctx->data, vlen); |
| 167 | |
| 168 | ctx->cert->tbs = value - hdrlen; |
| 169 | ctx->cert->tbs_size = vlen + hdrlen; |
| 170 | return 0; |
| 171 | } |
| 172 | |
| 173 | /* |
| 174 | * Record the public key algorithm |
| 175 | */ |
| 176 | int x509_note_pkey_algo(void *context, size_t hdrlen, |
| 177 | unsigned char tag, |
| 178 | const void *value, size_t vlen) |
| 179 | { |
| 180 | struct x509_parse_context *ctx = context; |
| 181 | |
| 182 | pr_debug("PubKey Algo: %u\n", ctx->last_oid); |
| 183 | |
| 184 | switch (ctx->last_oid) { |
| 185 | case OID_md2WithRSAEncryption: |
| 186 | case OID_md3WithRSAEncryption: |
| 187 | default: |
| 188 | return -ENOPKG; /* Unsupported combination */ |
| 189 | |
| 190 | case OID_md4WithRSAEncryption: |
Dmitry Kasatkin | 3fe78ca | 2013-05-06 15:58:15 +0300 | [diff] [blame] | 191 | ctx->cert->sig.pkey_hash_algo = HASH_ALGO_MD5; |
David Howells | b426beb | 2013-08-30 16:18:02 +0100 | [diff] [blame] | 192 | ctx->cert->sig.pkey_algo = PKEY_ALGO_RSA; |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 193 | break; |
| 194 | |
| 195 | case OID_sha1WithRSAEncryption: |
Dmitry Kasatkin | 3fe78ca | 2013-05-06 15:58:15 +0300 | [diff] [blame] | 196 | ctx->cert->sig.pkey_hash_algo = HASH_ALGO_SHA1; |
David Howells | b426beb | 2013-08-30 16:18:02 +0100 | [diff] [blame] | 197 | ctx->cert->sig.pkey_algo = PKEY_ALGO_RSA; |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 198 | break; |
| 199 | |
| 200 | case OID_sha256WithRSAEncryption: |
Dmitry Kasatkin | 3fe78ca | 2013-05-06 15:58:15 +0300 | [diff] [blame] | 201 | ctx->cert->sig.pkey_hash_algo = HASH_ALGO_SHA256; |
David Howells | b426beb | 2013-08-30 16:18:02 +0100 | [diff] [blame] | 202 | ctx->cert->sig.pkey_algo = PKEY_ALGO_RSA; |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 203 | break; |
| 204 | |
| 205 | case OID_sha384WithRSAEncryption: |
Dmitry Kasatkin | 3fe78ca | 2013-05-06 15:58:15 +0300 | [diff] [blame] | 206 | ctx->cert->sig.pkey_hash_algo = HASH_ALGO_SHA384; |
David Howells | b426beb | 2013-08-30 16:18:02 +0100 | [diff] [blame] | 207 | ctx->cert->sig.pkey_algo = PKEY_ALGO_RSA; |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 208 | break; |
| 209 | |
| 210 | case OID_sha512WithRSAEncryption: |
Dmitry Kasatkin | 3fe78ca | 2013-05-06 15:58:15 +0300 | [diff] [blame] | 211 | ctx->cert->sig.pkey_hash_algo = HASH_ALGO_SHA512; |
David Howells | b426beb | 2013-08-30 16:18:02 +0100 | [diff] [blame] | 212 | ctx->cert->sig.pkey_algo = PKEY_ALGO_RSA; |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 213 | break; |
| 214 | |
| 215 | case OID_sha224WithRSAEncryption: |
Dmitry Kasatkin | 3fe78ca | 2013-05-06 15:58:15 +0300 | [diff] [blame] | 216 | ctx->cert->sig.pkey_hash_algo = HASH_ALGO_SHA224; |
David Howells | b426beb | 2013-08-30 16:18:02 +0100 | [diff] [blame] | 217 | ctx->cert->sig.pkey_algo = PKEY_ALGO_RSA; |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 218 | break; |
| 219 | } |
| 220 | |
| 221 | ctx->algo_oid = ctx->last_oid; |
| 222 | return 0; |
| 223 | } |
| 224 | |
| 225 | /* |
| 226 | * Note the whereabouts and type of the signature. |
| 227 | */ |
| 228 | int x509_note_signature(void *context, size_t hdrlen, |
| 229 | unsigned char tag, |
| 230 | const void *value, size_t vlen) |
| 231 | { |
| 232 | struct x509_parse_context *ctx = context; |
| 233 | |
| 234 | pr_debug("Signature type: %u size %zu\n", ctx->last_oid, vlen); |
| 235 | |
| 236 | if (ctx->last_oid != ctx->algo_oid) { |
| 237 | pr_warn("Got cert with pkey (%u) and sig (%u) algorithm OIDs\n", |
| 238 | ctx->algo_oid, ctx->last_oid); |
| 239 | return -EINVAL; |
| 240 | } |
| 241 | |
David Howells | b426beb | 2013-08-30 16:18:02 +0100 | [diff] [blame] | 242 | ctx->cert->raw_sig = value; |
| 243 | ctx->cert->raw_sig_size = vlen; |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 244 | return 0; |
| 245 | } |
| 246 | |
| 247 | /* |
David Howells | 84aabd4 | 2014-07-01 16:40:19 +0100 | [diff] [blame] | 248 | * Note the certificate serial number |
| 249 | */ |
| 250 | int x509_note_serial(void *context, size_t hdrlen, |
| 251 | unsigned char tag, |
| 252 | const void *value, size_t vlen) |
| 253 | { |
| 254 | struct x509_parse_context *ctx = context; |
| 255 | ctx->cert->raw_serial = value; |
| 256 | ctx->cert->raw_serial_size = vlen; |
| 257 | return 0; |
| 258 | } |
| 259 | |
| 260 | /* |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 261 | * Note some of the name segments from which we'll fabricate a name. |
| 262 | */ |
| 263 | int x509_extract_name_segment(void *context, size_t hdrlen, |
| 264 | unsigned char tag, |
| 265 | const void *value, size_t vlen) |
| 266 | { |
| 267 | struct x509_parse_context *ctx = context; |
| 268 | |
| 269 | switch (ctx->last_oid) { |
| 270 | case OID_commonName: |
| 271 | ctx->cn_size = vlen; |
| 272 | ctx->cn_offset = (unsigned long)value - ctx->data; |
| 273 | break; |
| 274 | case OID_organizationName: |
| 275 | ctx->o_size = vlen; |
| 276 | ctx->o_offset = (unsigned long)value - ctx->data; |
| 277 | break; |
| 278 | case OID_email_address: |
| 279 | ctx->email_size = vlen; |
| 280 | ctx->email_offset = (unsigned long)value - ctx->data; |
| 281 | break; |
| 282 | default: |
| 283 | break; |
| 284 | } |
| 285 | |
| 286 | return 0; |
| 287 | } |
| 288 | |
| 289 | /* |
| 290 | * Fabricate and save the issuer and subject names |
| 291 | */ |
| 292 | static int x509_fabricate_name(struct x509_parse_context *ctx, size_t hdrlen, |
| 293 | unsigned char tag, |
| 294 | char **_name, size_t vlen) |
| 295 | { |
| 296 | const void *name, *data = (const void *)ctx->data; |
| 297 | size_t namesize; |
| 298 | char *buffer; |
| 299 | |
| 300 | if (*_name) |
| 301 | return -EINVAL; |
| 302 | |
| 303 | /* Empty name string if no material */ |
| 304 | if (!ctx->cn_size && !ctx->o_size && !ctx->email_size) { |
| 305 | buffer = kmalloc(1, GFP_KERNEL); |
| 306 | if (!buffer) |
| 307 | return -ENOMEM; |
| 308 | buffer[0] = 0; |
| 309 | goto done; |
| 310 | } |
| 311 | |
| 312 | if (ctx->cn_size && ctx->o_size) { |
| 313 | /* Consider combining O and CN, but use only the CN if it is |
| 314 | * prefixed by the O, or a significant portion thereof. |
| 315 | */ |
| 316 | namesize = ctx->cn_size; |
| 317 | name = data + ctx->cn_offset; |
| 318 | if (ctx->cn_size >= ctx->o_size && |
| 319 | memcmp(data + ctx->cn_offset, data + ctx->o_offset, |
| 320 | ctx->o_size) == 0) |
| 321 | goto single_component; |
| 322 | if (ctx->cn_size >= 7 && |
| 323 | ctx->o_size >= 7 && |
| 324 | memcmp(data + ctx->cn_offset, data + ctx->o_offset, 7) == 0) |
| 325 | goto single_component; |
| 326 | |
| 327 | buffer = kmalloc(ctx->o_size + 2 + ctx->cn_size + 1, |
| 328 | GFP_KERNEL); |
| 329 | if (!buffer) |
| 330 | return -ENOMEM; |
| 331 | |
| 332 | memcpy(buffer, |
| 333 | data + ctx->o_offset, ctx->o_size); |
| 334 | buffer[ctx->o_size + 0] = ':'; |
| 335 | buffer[ctx->o_size + 1] = ' '; |
| 336 | memcpy(buffer + ctx->o_size + 2, |
| 337 | data + ctx->cn_offset, ctx->cn_size); |
| 338 | buffer[ctx->o_size + 2 + ctx->cn_size] = 0; |
| 339 | goto done; |
| 340 | |
| 341 | } else if (ctx->cn_size) { |
| 342 | namesize = ctx->cn_size; |
| 343 | name = data + ctx->cn_offset; |
| 344 | } else if (ctx->o_size) { |
| 345 | namesize = ctx->o_size; |
| 346 | name = data + ctx->o_offset; |
| 347 | } else { |
| 348 | namesize = ctx->email_size; |
| 349 | name = data + ctx->email_offset; |
| 350 | } |
| 351 | |
| 352 | single_component: |
| 353 | buffer = kmalloc(namesize + 1, GFP_KERNEL); |
| 354 | if (!buffer) |
| 355 | return -ENOMEM; |
| 356 | memcpy(buffer, name, namesize); |
| 357 | buffer[namesize] = 0; |
| 358 | |
| 359 | done: |
| 360 | *_name = buffer; |
| 361 | ctx->cn_size = 0; |
| 362 | ctx->o_size = 0; |
| 363 | ctx->email_size = 0; |
| 364 | return 0; |
| 365 | } |
| 366 | |
| 367 | int x509_note_issuer(void *context, size_t hdrlen, |
| 368 | unsigned char tag, |
| 369 | const void *value, size_t vlen) |
| 370 | { |
| 371 | struct x509_parse_context *ctx = context; |
David Howells | 84aabd4 | 2014-07-01 16:40:19 +0100 | [diff] [blame] | 372 | ctx->cert->raw_issuer = value; |
| 373 | ctx->cert->raw_issuer_size = vlen; |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 374 | return x509_fabricate_name(ctx, hdrlen, tag, &ctx->cert->issuer, vlen); |
| 375 | } |
| 376 | |
| 377 | int x509_note_subject(void *context, size_t hdrlen, |
| 378 | unsigned char tag, |
| 379 | const void *value, size_t vlen) |
| 380 | { |
| 381 | struct x509_parse_context *ctx = context; |
David Howells | 84aabd4 | 2014-07-01 16:40:19 +0100 | [diff] [blame] | 382 | ctx->cert->raw_subject = value; |
| 383 | ctx->cert->raw_subject_size = vlen; |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 384 | return x509_fabricate_name(ctx, hdrlen, tag, &ctx->cert->subject, vlen); |
| 385 | } |
| 386 | |
| 387 | /* |
| 388 | * Extract the data for the public key algorithm |
| 389 | */ |
| 390 | int x509_extract_key_data(void *context, size_t hdrlen, |
| 391 | unsigned char tag, |
| 392 | const void *value, size_t vlen) |
| 393 | { |
| 394 | struct x509_parse_context *ctx = context; |
| 395 | |
| 396 | if (ctx->last_oid != OID_rsaEncryption) |
| 397 | return -ENOPKG; |
| 398 | |
David Howells | 67f7d60b | 2013-08-30 16:15:24 +0100 | [diff] [blame] | 399 | ctx->cert->pub->pkey_algo = PKEY_ALGO_RSA; |
| 400 | |
| 401 | /* Discard the BIT STRING metadata */ |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 402 | ctx->key = value + 1; |
| 403 | ctx->key_size = vlen - 1; |
| 404 | return 0; |
| 405 | } |
| 406 | |
| 407 | /* |
| 408 | * Extract a RSA public key value |
| 409 | */ |
| 410 | int rsa_extract_mpi(void *context, size_t hdrlen, |
| 411 | unsigned char tag, |
| 412 | const void *value, size_t vlen) |
| 413 | { |
| 414 | struct x509_parse_context *ctx = context; |
| 415 | MPI mpi; |
| 416 | |
| 417 | if (ctx->nr_mpi >= ARRAY_SIZE(ctx->cert->pub->mpi)) { |
| 418 | pr_err("Too many public key MPIs in certificate\n"); |
| 419 | return -EBADMSG; |
| 420 | } |
| 421 | |
| 422 | mpi = mpi_read_raw_data(value, vlen); |
| 423 | if (!mpi) |
| 424 | return -ENOMEM; |
| 425 | |
| 426 | ctx->cert->pub->mpi[ctx->nr_mpi++] = mpi; |
| 427 | return 0; |
| 428 | } |
| 429 | |
Chun-Yi Lee | 04b00bd | 2013-04-22 10:56:55 +0930 | [diff] [blame] | 430 | /* The keyIdentifier in AuthorityKeyIdentifier SEQUENCE is tag(CONT,PRIM,0) */ |
| 431 | #define SEQ_TAG_KEYID (ASN1_CONT << 6) |
| 432 | |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 433 | /* |
| 434 | * Process certificate extensions that are used to qualify the certificate. |
| 435 | */ |
| 436 | int x509_process_extension(void *context, size_t hdrlen, |
| 437 | unsigned char tag, |
| 438 | const void *value, size_t vlen) |
| 439 | { |
| 440 | struct x509_parse_context *ctx = context; |
David Howells | 46963b7 | 2014-09-16 17:36:13 +0100 | [diff] [blame] | 441 | struct asymmetric_key_id *kid; |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 442 | const unsigned char *v = value; |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 443 | |
| 444 | pr_debug("Extension: %u\n", ctx->last_oid); |
| 445 | |
| 446 | if (ctx->last_oid == OID_subjectKeyIdentifier) { |
| 447 | /* Get hold of the key fingerprint */ |
David Howells | 46963b7 | 2014-09-16 17:36:13 +0100 | [diff] [blame] | 448 | if (ctx->cert->skid || vlen < 3) |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 449 | return -EBADMSG; |
| 450 | if (v[0] != ASN1_OTS || v[1] != vlen - 2) |
| 451 | return -EBADMSG; |
| 452 | v += 2; |
| 453 | vlen -= 2; |
| 454 | |
David Howells | dd2f6c4 | 2014-10-03 16:17:02 +0100 | [diff] [blame] | 455 | ctx->cert->raw_skid_size = vlen; |
| 456 | ctx->cert->raw_skid = v; |
David Howells | a4c6e57 | 2015-07-20 21:16:32 +0100 | [diff] [blame] | 457 | kid = asymmetric_key_generate_id(v, vlen, "", 0); |
David Howells | 46963b7 | 2014-09-16 17:36:13 +0100 | [diff] [blame] | 458 | if (IS_ERR(kid)) |
| 459 | return PTR_ERR(kid); |
| 460 | ctx->cert->skid = kid; |
| 461 | pr_debug("subjkeyid %*phN\n", kid->len, kid->data); |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 462 | return 0; |
| 463 | } |
| 464 | |
| 465 | if (ctx->last_oid == OID_authorityKeyIdentifier) { |
| 466 | /* Get hold of the CA key fingerprint */ |
David Howells | b92e657 | 2015-07-20 21:16:26 +0100 | [diff] [blame] | 467 | ctx->raw_akid = v; |
| 468 | ctx->raw_akid_size = vlen; |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 469 | return 0; |
| 470 | } |
| 471 | |
| 472 | return 0; |
| 473 | } |
| 474 | |
David Howells | fd19a3d | 2015-07-29 16:58:32 +0100 | [diff] [blame] | 475 | /** |
| 476 | * x509_decode_time - Decode an X.509 time ASN.1 object |
| 477 | * @_t: The time to fill in |
| 478 | * @hdrlen: The length of the object header |
| 479 | * @tag: The object tag |
| 480 | * @value: The object value |
| 481 | * @vlen: The size of the object value |
| 482 | * |
| 483 | * Decode an ASN.1 universal time or generalised time field into a struct the |
| 484 | * kernel can handle and check it for validity. The time is decoded thus: |
| 485 | * |
| 486 | * [RFC5280 §4.1.2.5] |
| 487 | * CAs conforming to this profile MUST always encode certificate validity |
| 488 | * dates through the year 2049 as UTCTime; certificate validity dates in |
| 489 | * 2050 or later MUST be encoded as GeneralizedTime. Conforming |
| 490 | * applications MUST be able to process validity dates that are encoded in |
| 491 | * either UTCTime or GeneralizedTime. |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 492 | */ |
David Howells | fd19a3d | 2015-07-29 16:58:32 +0100 | [diff] [blame] | 493 | int x509_decode_time(time64_t *_t, size_t hdrlen, |
| 494 | unsigned char tag, |
| 495 | const unsigned char *value, size_t vlen) |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 496 | { |
David Howells | fd19a3d | 2015-07-29 16:58:32 +0100 | [diff] [blame] | 497 | static const unsigned char month_lengths[] = { 31, 29, 31, 30, 31, 30, |
| 498 | 31, 31, 30, 31, 30, 31 }; |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 499 | const unsigned char *p = value; |
David Howells | fd19a3d | 2015-07-29 16:58:32 +0100 | [diff] [blame] | 500 | unsigned year, mon, day, hour, min, sec, mon_len; |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 501 | |
David Howells | fd19a3d | 2015-07-29 16:58:32 +0100 | [diff] [blame] | 502 | #define dec2bin(X) ({ unsigned char x = (X) - '0'; if (x > 9) goto invalid_time; x; }) |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 503 | #define DD2bin(P) ({ unsigned x = dec2bin(P[0]) * 10 + dec2bin(P[1]); P += 2; x; }) |
| 504 | |
| 505 | if (tag == ASN1_UNITIM) { |
| 506 | /* UTCTime: YYMMDDHHMMSSZ */ |
| 507 | if (vlen != 13) |
| 508 | goto unsupported_time; |
David Howells | fd19a3d | 2015-07-29 16:58:32 +0100 | [diff] [blame] | 509 | year = DD2bin(p); |
| 510 | if (year >= 50) |
| 511 | year += 1900; |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 512 | else |
David Howells | fd19a3d | 2015-07-29 16:58:32 +0100 | [diff] [blame] | 513 | year += 2000; |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 514 | } else if (tag == ASN1_GENTIM) { |
| 515 | /* GenTime: YYYYMMDDHHMMSSZ */ |
| 516 | if (vlen != 15) |
| 517 | goto unsupported_time; |
David Howells | fd19a3d | 2015-07-29 16:58:32 +0100 | [diff] [blame] | 518 | year = DD2bin(p) * 100 + DD2bin(p); |
| 519 | if (year >= 1950 && year <= 2049) |
| 520 | goto invalid_time; |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 521 | } else { |
| 522 | goto unsupported_time; |
| 523 | } |
| 524 | |
David Howells | fd19a3d | 2015-07-29 16:58:32 +0100 | [diff] [blame] | 525 | mon = DD2bin(p); |
| 526 | day = DD2bin(p); |
| 527 | hour = DD2bin(p); |
| 528 | min = DD2bin(p); |
| 529 | sec = DD2bin(p); |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 530 | |
| 531 | if (*p != 'Z') |
| 532 | goto unsupported_time; |
| 533 | |
David Howells | cc25b99 | 2015-11-12 09:36:40 +0000 | [diff] [blame] | 534 | if (year < 1970 || |
| 535 | mon < 1 || mon > 12) |
| 536 | goto invalid_time; |
| 537 | |
| 538 | mon_len = month_lengths[mon - 1]; |
David Howells | fd19a3d | 2015-07-29 16:58:32 +0100 | [diff] [blame] | 539 | if (mon == 2) { |
| 540 | if (year % 4 == 0) { |
| 541 | mon_len = 29; |
| 542 | if (year % 100 == 0) { |
| 543 | year /= 100; |
| 544 | if (year % 4 != 0) |
| 545 | mon_len = 28; |
| 546 | } |
| 547 | } |
| 548 | } |
| 549 | |
David Howells | cc25b99 | 2015-11-12 09:36:40 +0000 | [diff] [blame] | 550 | if (day < 1 || day > mon_len || |
sudip | 4dd17c9 | 2015-09-17 13:12:51 +0530 | [diff] [blame] | 551 | hour > 23 || |
| 552 | min > 59 || |
| 553 | sec > 59) |
David Howells | fd19a3d | 2015-07-29 16:58:32 +0100 | [diff] [blame] | 554 | goto invalid_time; |
David Howells | cc25b99 | 2015-11-12 09:36:40 +0000 | [diff] [blame] | 555 | |
David Howells | fd19a3d | 2015-07-29 16:58:32 +0100 | [diff] [blame] | 556 | *_t = mktime64(year, mon, day, hour, min, sec); |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 557 | return 0; |
| 558 | |
| 559 | unsupported_time: |
David Howells | fd19a3d | 2015-07-29 16:58:32 +0100 | [diff] [blame] | 560 | pr_debug("Got unsupported time [tag %02x]: '%*phN'\n", |
| 561 | tag, (int)vlen, value); |
| 562 | return -EBADMSG; |
| 563 | invalid_time: |
| 564 | pr_debug("Got invalid time [tag %02x]: '%*phN'\n", |
| 565 | tag, (int)vlen, value); |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 566 | return -EBADMSG; |
| 567 | } |
David Howells | fd19a3d | 2015-07-29 16:58:32 +0100 | [diff] [blame] | 568 | EXPORT_SYMBOL_GPL(x509_decode_time); |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 569 | |
| 570 | int x509_note_not_before(void *context, size_t hdrlen, |
| 571 | unsigned char tag, |
| 572 | const void *value, size_t vlen) |
| 573 | { |
| 574 | struct x509_parse_context *ctx = context; |
David Howells | fd19a3d | 2015-07-29 16:58:32 +0100 | [diff] [blame] | 575 | return x509_decode_time(&ctx->cert->valid_from, hdrlen, tag, value, vlen); |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 576 | } |
| 577 | |
| 578 | int x509_note_not_after(void *context, size_t hdrlen, |
| 579 | unsigned char tag, |
| 580 | const void *value, size_t vlen) |
| 581 | { |
| 582 | struct x509_parse_context *ctx = context; |
David Howells | fd19a3d | 2015-07-29 16:58:32 +0100 | [diff] [blame] | 583 | return x509_decode_time(&ctx->cert->valid_to, hdrlen, tag, value, vlen); |
David Howells | c26fd69 | 2012-09-24 17:11:48 +0100 | [diff] [blame] | 584 | } |
David Howells | b92e657 | 2015-07-20 21:16:26 +0100 | [diff] [blame] | 585 | |
| 586 | /* |
| 587 | * Note a key identifier-based AuthorityKeyIdentifier |
| 588 | */ |
| 589 | int x509_akid_note_kid(void *context, size_t hdrlen, |
| 590 | unsigned char tag, |
| 591 | const void *value, size_t vlen) |
| 592 | { |
| 593 | struct x509_parse_context *ctx = context; |
| 594 | struct asymmetric_key_id *kid; |
| 595 | |
| 596 | pr_debug("AKID: keyid: %*phN\n", (int)vlen, value); |
| 597 | |
| 598 | if (ctx->cert->akid_skid) |
| 599 | return 0; |
| 600 | |
David Howells | a4c6e57 | 2015-07-20 21:16:32 +0100 | [diff] [blame] | 601 | kid = asymmetric_key_generate_id(value, vlen, "", 0); |
David Howells | b92e657 | 2015-07-20 21:16:26 +0100 | [diff] [blame] | 602 | if (IS_ERR(kid)) |
| 603 | return PTR_ERR(kid); |
| 604 | pr_debug("authkeyid %*phN\n", kid->len, kid->data); |
| 605 | ctx->cert->akid_skid = kid; |
| 606 | return 0; |
| 607 | } |
| 608 | |
| 609 | /* |
| 610 | * Note a directoryName in an AuthorityKeyIdentifier |
| 611 | */ |
| 612 | int x509_akid_note_name(void *context, size_t hdrlen, |
| 613 | unsigned char tag, |
| 614 | const void *value, size_t vlen) |
| 615 | { |
| 616 | struct x509_parse_context *ctx = context; |
| 617 | |
| 618 | pr_debug("AKID: name: %*phN\n", (int)vlen, value); |
| 619 | |
| 620 | ctx->akid_raw_issuer = value; |
| 621 | ctx->akid_raw_issuer_size = vlen; |
| 622 | return 0; |
| 623 | } |
| 624 | |
| 625 | /* |
| 626 | * Note a serial number in an AuthorityKeyIdentifier |
| 627 | */ |
| 628 | int x509_akid_note_serial(void *context, size_t hdrlen, |
| 629 | unsigned char tag, |
| 630 | const void *value, size_t vlen) |
| 631 | { |
| 632 | struct x509_parse_context *ctx = context; |
| 633 | struct asymmetric_key_id *kid; |
| 634 | |
| 635 | pr_debug("AKID: serial: %*phN\n", (int)vlen, value); |
| 636 | |
| 637 | if (!ctx->akid_raw_issuer || ctx->cert->akid_id) |
| 638 | return 0; |
| 639 | |
| 640 | kid = asymmetric_key_generate_id(value, |
| 641 | vlen, |
| 642 | ctx->akid_raw_issuer, |
| 643 | ctx->akid_raw_issuer_size); |
| 644 | if (IS_ERR(kid)) |
| 645 | return PTR_ERR(kid); |
| 646 | |
| 647 | pr_debug("authkeyid %*phN\n", kid->len, kid->data); |
| 648 | ctx->cert->akid_id = kid; |
| 649 | return 0; |
| 650 | } |