Linux/certs/blacklist.c

Version: ~ [ linux-6.11.5 ] ~ [ linux-6.10.14 ] ~ [ linux-6.9.12 ] ~ [ linux-6.8.12 ] ~ [ linux-6.7.12 ] ~ [ linux-6.6.58 ] ~ [ linux-6.5.13 ] ~ [ linux-6.4.16 ] ~ [ linux-6.3.13 ] ~ [ linux-6.2.16 ] ~ [ linux-6.1.114 ] ~ [ linux-6.0.19 ] ~ [ linux-5.19.17 ] ~ [ linux-5.18.19 ] ~ [ linux-5.17.15 ] ~ [ linux-5.16.20 ] ~ [ linux-5.15.169 ] ~ [ linux-5.14.21 ] ~ [ linux-5.13.19 ] ~ [ linux-5.12.19 ] ~ [ linux-5.11.22 ] ~ [ linux-5.10.228 ] ~ [ linux-5.9.16 ] ~ [ linux-5.8.18 ] ~ [ linux-5.7.19 ] ~ [ linux-5.6.19 ] ~ [ linux-5.5.19 ] ~ [ linux-5.4.284 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.322 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.336 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.337 ] ~ [ linux-4.4.302 ] ~ [ linux-3.10.108 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.9 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

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1 // SPDX-License-Identifier: GPL-2.0-or-later << 2 /* System hash blacklist. 1 /* System hash blacklist. 3 * 2 * 4 * Copyright (C) 2016 Red Hat, Inc. All Rights 3 * Copyright (C) 2016 Red Hat, Inc. All Rights Reserved. 5 * Written by David Howells (dhowells@redhat.c 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. 6 */ 10 */ 7 11 8 #define pr_fmt(fmt) "blacklist: "fmt 12 #define pr_fmt(fmt) "blacklist: "fmt 9 #include <linux/module.h> 13 #include <linux/module.h> 10 #include <linux/slab.h> 14 #include <linux/slab.h> 11 #include <linux/key.h> 15 #include <linux/key.h> 12 #include <linux/key-type.h> 16 #include <linux/key-type.h> 13 #include <linux/sched.h> 17 #include <linux/sched.h> 14 #include <linux/ctype.h> 18 #include <linux/ctype.h> 15 #include <linux/err.h> 19 #include <linux/err.h> 16 #include <linux/seq_file.h> 20 #include <linux/seq_file.h> 17 #include <linux/uidgid.h> << 18 #include <keys/asymmetric-type.h> << 19 #include <keys/system_keyring.h> 21 #include <keys/system_keyring.h> 20 #include "blacklist.h" 22 #include "blacklist.h" 21 23 22 /* << 23 * According to crypto/asymmetric_keys/x509_ce << 24 * the size of the currently longest supported << 25 * which translates into 128 hex characters. << 26 */ << 27 #define MAX_HASH_LEN 128 << 28 << 29 #define BLACKLIST_KEY_PERM (KEY_POS_SEARCH | K << 30 KEY_USR_SEARCH | K << 31 << 32 static const char tbs_prefix[] = "tbs"; << 33 static const char bin_prefix[] = "bin"; << 34 << 35 static struct key *blacklist_keyring; 24 static struct key *blacklist_keyring; 36 25 37 #ifdef CONFIG_SYSTEM_REVOCATION_LIST << 38 extern __initconst const u8 revocation_certifi << 39 extern __initconst const unsigned long revocat << 40 #endif << 41 << 42 /* 26 /* 43 * The description must be a type prefix, a co 27 * The description must be a type prefix, a colon and then an even number of 44 * hex digits. The hash is kept in the descri 28 * hex digits. The hash is kept in the description. 45 */ 29 */ 46 static int blacklist_vet_description(const cha 30 static int blacklist_vet_description(const char *desc) 47 { 31 { 48 int i, prefix_len, tbs_step = 0, bin_s !! 32 int n = 0; 49 33 50 /* The following algorithm only works !! 34 if (*desc == ':') 51 BUILD_BUG_ON(sizeof(tbs_prefix) != siz !! 35 return -EINVAL; 52 prefix_len = sizeof(tbs_prefix) - 1; !! 36 for (; *desc; desc++) 53 for (i = 0; *desc; desc++, i++) { !! 37 if (*desc == ':') 54 if (*desc == ':') { !! 38 goto found_colon; 55 if (tbs_step == prefix << 56 goto found_col << 57 if (bin_step == prefix << 58 goto found_col << 59 return -EINVAL; << 60 } << 61 if (i >= prefix_len) << 62 return -EINVAL; << 63 if (*desc == tbs_prefix[i]) << 64 tbs_step++; << 65 if (*desc == bin_prefix[i]) << 66 bin_step++; << 67 } << 68 return -EINVAL; 39 return -EINVAL; 69 40 70 found_colon: 41 found_colon: 71 desc++; 42 desc++; 72 for (i = 0; *desc && i < MAX_HASH_LEN; !! 43 for (; *desc; desc++) { 73 if (!isxdigit(*desc) || isuppe !! 44 if (!isxdigit(*desc)) 74 return -EINVAL; 45 return -EINVAL; >> 46 n++; 75 } 47 } 76 if (*desc) << 77 /* The hash is greater than MA << 78 return -ENOPKG; << 79 48 80 /* Checks for an even number of hexade !! 49 if (n == 0 || n & 1) 81 if (i == 0 || i & 1) << 82 return -EINVAL; 50 return -EINVAL; 83 return 0; 51 return 0; 84 } 52 } 85 53 86 static int blacklist_key_instantiate(struct ke !! 54 /* 87 struct key_preparsed_payload * !! 55 * The hash to be blacklisted is expected to be in the description. There will >> 56 * be no payload. >> 57 */ >> 58 static int blacklist_preparse(struct key_preparsed_payload *prep) 88 { 59 { 89 #ifdef CONFIG_SYSTEM_BLACKLIST_AUTH_UPDATE !! 60 if (prep->datalen > 0) 90 int err; !! 61 return -EINVAL; 91 #endif !! 62 return 0; 92 << 93 /* Sets safe default permissions for k << 94 key->perm = BLACKLIST_KEY_PERM; << 95 << 96 /* << 97 * Skips the authentication step for b << 98 * signed but still trusted. << 99 */ << 100 if (key->flags & (1 << KEY_FLAG_BUILTI << 101 goto out; << 102 << 103 #ifdef CONFIG_SYSTEM_BLACKLIST_AUTH_UPDATE << 104 /* << 105 * Verifies the description's PKCS#7 s << 106 * trusted keyring. << 107 */ << 108 err = verify_pkcs7_signature(key->desc << 109 strlen(key->descriptio << 110 NULL, VERIFYING_UNSPEC << 111 if (err) << 112 return err; << 113 #else << 114 /* << 115 * It should not be possible to come h << 116 * have KEY_USR_WRITE and the only oth << 117 * for builtin hashes. << 118 */ << 119 WARN_ON_ONCE(1); << 120 return -EPERM; << 121 #endif << 122 << 123 out: << 124 return generic_key_instantiate(key, pr << 125 } 63 } 126 64 127 static int blacklist_key_update(struct key *ke !! 65 static void blacklist_free_preparse(struct key_preparsed_payload *prep) 128 struct key_preparsed_payload * << 129 { 66 { 130 return -EPERM; << 131 } 67 } 132 68 133 static void blacklist_describe(const struct ke 69 static void blacklist_describe(const struct key *key, struct seq_file *m) 134 { 70 { 135 seq_puts(m, key->description); 71 seq_puts(m, key->description); 136 } 72 } 137 73 138 static struct key_type key_type_blacklist = { 74 static struct key_type key_type_blacklist = { 139 .name = "blacklist", 75 .name = "blacklist", 140 .vet_description = blacklist_ve 76 .vet_description = blacklist_vet_description, 141 .instantiate = blacklist_ke !! 77 .preparse = blacklist_preparse, 142 .update = blacklist_ke !! 78 .free_preparse = blacklist_free_preparse, >> 79 .instantiate = generic_key_instantiate, 143 .describe = blacklist_de 80 .describe = blacklist_describe, 144 }; 81 }; 145 82 146 static char *get_raw_hash(const u8 *hash, size << 147 enum blacklist_hash_type hash_ << 148 { << 149 size_t type_len; << 150 const char *type_prefix; << 151 char *buffer, *p; << 152 << 153 switch (hash_type) { << 154 case BLACKLIST_HASH_X509_TBS: << 155 type_len = sizeof(tbs_prefix) << 156 type_prefix = tbs_prefix; << 157 break; << 158 case BLACKLIST_HASH_BINARY: << 159 type_len = sizeof(bin_prefix) << 160 type_prefix = bin_prefix; << 161 break; << 162 default: << 163 WARN_ON_ONCE(1); << 164 return ERR_PTR(-EINVAL); << 165 } << 166 buffer = kmalloc(type_len + 1 + hash_l << 167 if (!buffer) << 168 return ERR_PTR(-ENOMEM); << 169 p = memcpy(buffer, type_prefix, type_l << 170 p += type_len; << 171 *p++ = ':'; << 172 bin2hex(p, hash, hash_len); << 173 p += hash_len * 2; << 174 *p = '\0'; << 175 return buffer; << 176 } << 177 << 178 /** 83 /** 179 * mark_raw_hash_blacklisted - Add a hash to t !! 84 * mark_hash_blacklisted - Add a hash to the system blacklist 180 * @hash: The hash as a hex string with a type !! 85 * @hash - The hash as a hex string with a type prefix (eg. "tbs:23aa429783") 181 */ 86 */ 182 static int mark_raw_hash_blacklisted(const cha !! 87 int mark_hash_blacklisted(const char *hash) 183 { 88 { 184 key_ref_t key; 89 key_ref_t key; 185 90 186 key = key_create(make_key_ref(blacklis !! 91 key = key_create_or_update(make_key_ref(blacklist_keyring, true), 187 "blacklist", !! 92 "blacklist", 188 hash, !! 93 hash, 189 NULL, !! 94 NULL, 190 0, !! 95 0, 191 BLACKLIST_KEY_PERM, !! 96 ((KEY_POS_ALL & ~KEY_POS_SETATTR) | 192 KEY_ALLOC_NOT_IN_QUOT !! 97 KEY_USR_VIEW), 193 KEY_ALLOC_BUILT_IN); !! 98 KEY_ALLOC_NOT_IN_QUOTA | >> 99 KEY_ALLOC_BUILT_IN); 194 if (IS_ERR(key)) { 100 if (IS_ERR(key)) { 195 if (PTR_ERR(key) == -EEXIST) !! 101 pr_err("Problem blacklisting hash (%ld)\n", PTR_ERR(key)); 196 pr_warn("Duplicate bla << 197 else << 198 pr_err("Problem blackl << 199 return PTR_ERR(key); 102 return PTR_ERR(key); 200 } 103 } 201 return 0; 104 return 0; 202 } 105 } 203 106 204 int mark_hash_blacklisted(const u8 *hash, size << 205 enum blacklist_hash_type hash_ << 206 { << 207 const char *buffer; << 208 int err; << 209 << 210 buffer = get_raw_hash(hash, hash_len, << 211 if (IS_ERR(buffer)) << 212 return PTR_ERR(buffer); << 213 err = mark_raw_hash_blacklisted(buffer << 214 kfree(buffer); << 215 return err; << 216 } << 217 << 218 /** 107 /** 219 * is_hash_blacklisted - Determine if a hash i 108 * is_hash_blacklisted - Determine if a hash is blacklisted 220 * @hash: The hash to be checked as a binary b 109 * @hash: The hash to be checked as a binary blob 221 * @hash_len: The length of the binary hash 110 * @hash_len: The length of the binary hash 222 * @hash_type: Type of hash !! 111 * @type: Type of hash 223 */ 112 */ 224 int is_hash_blacklisted(const u8 *hash, size_t !! 113 int is_hash_blacklisted(const u8 *hash, size_t hash_len, const char *type) 225 enum blacklist_hash_type hash_ << 226 { 114 { 227 key_ref_t kref; 115 key_ref_t kref; 228 const char *buffer; !! 116 size_t type_len = strlen(type); >> 117 char *buffer, *p; 229 int ret = 0; 118 int ret = 0; 230 119 231 buffer = get_raw_hash(hash, hash_len, !! 120 buffer = kmalloc(type_len + 1 + hash_len * 2 + 1, GFP_KERNEL); 232 if (IS_ERR(buffer)) !! 121 if (!buffer) 233 return PTR_ERR(buffer); !! 122 return -ENOMEM; >> 123 p = memcpy(buffer, type, type_len); >> 124 p += type_len; >> 125 *p++ = ':'; >> 126 bin2hex(p, hash, hash_len); >> 127 p += hash_len * 2; >> 128 *p = 0; >> 129 234 kref = keyring_search(make_key_ref(bla 130 kref = keyring_search(make_key_ref(blacklist_keyring, true), 235 &key_type_blackl !! 131 &key_type_blacklist, buffer); 236 if (!IS_ERR(kref)) { 132 if (!IS_ERR(kref)) { 237 key_ref_put(kref); 133 key_ref_put(kref); 238 ret = -EKEYREJECTED; 134 ret = -EKEYREJECTED; 239 } 135 } 240 136 241 kfree(buffer); 137 kfree(buffer); 242 return ret; 138 return ret; 243 } 139 } 244 EXPORT_SYMBOL_GPL(is_hash_blacklisted); 140 EXPORT_SYMBOL_GPL(is_hash_blacklisted); 245 141 246 int is_binary_blacklisted(const u8 *hash, size << 247 { << 248 if (is_hash_blacklisted(hash, hash_len << 249 -EKEYREJECTED) << 250 return -EPERM; << 251 << 252 return 0; << 253 } << 254 EXPORT_SYMBOL_GPL(is_binary_blacklisted); << 255 << 256 #ifdef CONFIG_SYSTEM_REVOCATION_LIST << 257 /** << 258 * add_key_to_revocation_list - Add a revocati << 259 * @data: The data blob containing the certifi << 260 * @size: The size of data blob << 261 */ << 262 int add_key_to_revocation_list(const char *dat << 263 { << 264 key_ref_t key; << 265 << 266 key = key_create_or_update(make_key_re << 267 "asymmetric << 268 NULL, << 269 data, << 270 size, << 271 KEY_POS_VIE << 272 | KEY_USR_V << 273 KEY_ALLOC_N << 274 | KEY_ALLOC << 275 << 276 if (IS_ERR(key)) { << 277 pr_err("Problem with revocatio << 278 return PTR_ERR(key); << 279 } << 280 << 281 return 0; << 282 } << 283 << 284 /** << 285 * is_key_on_revocation_list - Determine if th << 286 * @pkcs7: The PKCS#7 message to check << 287 */ << 288 int is_key_on_revocation_list(struct pkcs7_mes << 289 { << 290 int ret; << 291 << 292 ret = pkcs7_validate_trust(pkcs7, blac << 293 << 294 if (ret == 0) << 295 return -EKEYREJECTED; << 296 << 297 return -ENOKEY; << 298 } << 299 #endif << 300 << 301 static int restrict_link_for_blacklist(struct << 302 const struct key_type *type, c << 303 struct key *restrict_key) << 304 { << 305 if (type == &key_type_blacklist) << 306 return 0; << 307 return -EOPNOTSUPP; << 308 } << 309 << 310 /* 142 /* 311 * Initialise the blacklist 143 * Initialise the blacklist 312 * << 313 * The blacklist_init() function is registered << 314 * device_initcall(). As a result if the blac << 315 * any reason the kernel continues to execute. << 316 * could be acceptable for some non-critical k << 317 * keyring fails to load it defeats the certif << 318 * signed modules. If a critical piece of sec << 319 * expect to be present fails to initialize, p << 320 * thing to do. << 321 */ 144 */ 322 static int __init blacklist_init(void) 145 static int __init blacklist_init(void) 323 { 146 { 324 const char *const *bl; 147 const char *const *bl; 325 struct key_restriction *restriction; << 326 148 327 if (register_key_type(&key_type_blackl 149 if (register_key_type(&key_type_blacklist) < 0) 328 panic("Can't allocate system b 150 panic("Can't allocate system blacklist key type\n"); 329 151 330 restriction = kzalloc(sizeof(*restrict << 331 if (!restriction) << 332 panic("Can't allocate blacklis << 333 restriction->check = restrict_link_for << 334 << 335 blacklist_keyring = 152 blacklist_keyring = 336 keyring_alloc(".blacklist", 153 keyring_alloc(".blacklist", 337 GLOBAL_ROOT_UID, !! 154 KUIDT_INIT(0), KGIDT_INIT(0), 338 KEY_POS_VIEW | K !! 155 current_cred(), 339 KEY_POS_WRITE | !! 156 (KEY_POS_ALL & ~KEY_POS_SETATTR) | 340 KEY_USR_VIEW | K !! 157 KEY_USR_VIEW | KEY_USR_READ | 341 #ifdef CONFIG_SYSTEM_BLACKLIST_AUTH_UPDATE !! 158 KEY_USR_SEARCH, 342 | KEY_USR_WRITE !! 159 KEY_ALLOC_NOT_IN_QUOTA | 343 #endif !! 160 KEY_FLAG_KEEP, 344 , KEY_ALLOC_NOT_ !! 161 NULL, NULL); 345 KEY_ALLOC_SET_KE << 346 restriction, NUL << 347 if (IS_ERR(blacklist_keyring)) 162 if (IS_ERR(blacklist_keyring)) 348 panic("Can't allocate system b 163 panic("Can't allocate system blacklist keyring\n"); 349 164 350 for (bl = blacklist_hashes; *bl; bl++) 165 for (bl = blacklist_hashes; *bl; bl++) 351 if (mark_raw_hash_blacklisted( !! 166 if (mark_hash_blacklisted(*bl) < 0) 352 pr_err("- blacklisting 167 pr_err("- blacklisting failed\n"); 353 return 0; 168 return 0; 354 } 169 } 355 170 356 /* 171 /* 357 * Must be initialised before we try and load 172 * Must be initialised before we try and load the keys into the keyring. 358 */ 173 */ 359 device_initcall(blacklist_init); 174 device_initcall(blacklist_init); 360 << 361 #ifdef CONFIG_SYSTEM_REVOCATION_LIST << 362 /* << 363 * Load the compiled-in list of revocation X.5 << 364 */ << 365 static __init int load_revocation_certificate_ << 366 { << 367 if (revocation_certificate_list_size) << 368 pr_notice("Loading compiled-in << 369 << 370 return x509_load_certificate_list(revo << 371 revo << 372 blac << 373 } << 374 late_initcall(load_revocation_certificate_list << 375 #endif << 376 175

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TOMOYO Linux Cross Reference
Linux/certs/blacklist.c

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Differences between /certs/blacklist.c (Version linux-6.11.5) and /certs/blacklist.c (Version linux-4.13.16)

TOMOYO Linux Cross Reference Linux/certs/blacklist.c

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Differences between /certs/blacklist.c (Version linux-6.11.5) and /certs/blacklist.c (Version linux-4.13.16)

TOMOYO Linux Cross Reference
Linux/certs/blacklist.c