lh | 9ed821d | 2023-04-07 01:36:19 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2016-2018 The OpenSSL Project Authors. All Rights Reserved. |
| 3 | * |
| 4 | * Licensed under the OpenSSL license (the "License"). You may not use |
| 5 | * this file except in compliance with the License. You can obtain a copy |
| 6 | * in the file LICENSE in the source distribution or at |
| 7 | * https://www.openssl.org/source/license.html |
| 8 | */ |
| 9 | |
| 10 | #ifndef HEADER_CT_H |
| 11 | # define HEADER_CT_H |
| 12 | |
| 13 | # include <openssl/opensslconf.h> |
| 14 | |
| 15 | # ifndef OPENSSL_NO_CT |
| 16 | # include <openssl/ossl_typ.h> |
| 17 | # include <openssl/safestack.h> |
| 18 | # include <openssl/x509.h> |
| 19 | # include <openssl/cterr.h> |
| 20 | # ifdef __cplusplus |
| 21 | extern "C" { |
| 22 | # endif |
| 23 | |
| 24 | |
| 25 | /* Minimum RSA key size, from RFC6962 */ |
| 26 | # define SCT_MIN_RSA_BITS 2048 |
| 27 | |
| 28 | /* All hashes are SHA256 in v1 of Certificate Transparency */ |
| 29 | # define CT_V1_HASHLEN SHA256_DIGEST_LENGTH |
| 30 | |
| 31 | typedef enum { |
| 32 | CT_LOG_ENTRY_TYPE_NOT_SET = -1, |
| 33 | CT_LOG_ENTRY_TYPE_X509 = 0, |
| 34 | CT_LOG_ENTRY_TYPE_PRECERT = 1 |
| 35 | } ct_log_entry_type_t; |
| 36 | |
| 37 | typedef enum { |
| 38 | SCT_VERSION_NOT_SET = -1, |
| 39 | SCT_VERSION_V1 = 0 |
| 40 | } sct_version_t; |
| 41 | |
| 42 | typedef enum { |
| 43 | SCT_SOURCE_UNKNOWN, |
| 44 | SCT_SOURCE_TLS_EXTENSION, |
| 45 | SCT_SOURCE_X509V3_EXTENSION, |
| 46 | SCT_SOURCE_OCSP_STAPLED_RESPONSE |
| 47 | } sct_source_t; |
| 48 | |
| 49 | typedef enum { |
| 50 | SCT_VALIDATION_STATUS_NOT_SET, |
| 51 | SCT_VALIDATION_STATUS_UNKNOWN_LOG, |
| 52 | SCT_VALIDATION_STATUS_VALID, |
| 53 | SCT_VALIDATION_STATUS_INVALID, |
| 54 | SCT_VALIDATION_STATUS_UNVERIFIED, |
| 55 | SCT_VALIDATION_STATUS_UNKNOWN_VERSION |
| 56 | } sct_validation_status_t; |
| 57 | |
| 58 | DEFINE_STACK_OF(SCT) |
| 59 | DEFINE_STACK_OF(CTLOG) |
| 60 | |
| 61 | /****************************************** |
| 62 | * CT policy evaluation context functions * |
| 63 | ******************************************/ |
| 64 | |
| 65 | /* |
| 66 | * Creates a new, empty policy evaluation context. |
| 67 | * The caller is responsible for calling CT_POLICY_EVAL_CTX_free when finished |
| 68 | * with the CT_POLICY_EVAL_CTX. |
| 69 | */ |
| 70 | CT_POLICY_EVAL_CTX *CT_POLICY_EVAL_CTX_new(void); |
| 71 | |
| 72 | /* Deletes a policy evaluation context and anything it owns. */ |
| 73 | void CT_POLICY_EVAL_CTX_free(CT_POLICY_EVAL_CTX *ctx); |
| 74 | |
| 75 | /* Gets the peer certificate that the SCTs are for */ |
| 76 | X509* CT_POLICY_EVAL_CTX_get0_cert(const CT_POLICY_EVAL_CTX *ctx); |
| 77 | |
| 78 | /* |
| 79 | * Sets the certificate associated with the received SCTs. |
| 80 | * Increments the reference count of cert. |
| 81 | * Returns 1 on success, 0 otherwise. |
| 82 | */ |
| 83 | int CT_POLICY_EVAL_CTX_set1_cert(CT_POLICY_EVAL_CTX *ctx, X509 *cert); |
| 84 | |
| 85 | /* Gets the issuer of the aforementioned certificate */ |
| 86 | X509* CT_POLICY_EVAL_CTX_get0_issuer(const CT_POLICY_EVAL_CTX *ctx); |
| 87 | |
| 88 | /* |
| 89 | * Sets the issuer of the certificate associated with the received SCTs. |
| 90 | * Increments the reference count of issuer. |
| 91 | * Returns 1 on success, 0 otherwise. |
| 92 | */ |
| 93 | int CT_POLICY_EVAL_CTX_set1_issuer(CT_POLICY_EVAL_CTX *ctx, X509 *issuer); |
| 94 | |
| 95 | /* Gets the CT logs that are trusted sources of SCTs */ |
| 96 | const CTLOG_STORE *CT_POLICY_EVAL_CTX_get0_log_store(const CT_POLICY_EVAL_CTX *ctx); |
| 97 | |
| 98 | /* Sets the log store that is in use. It must outlive the CT_POLICY_EVAL_CTX. */ |
| 99 | void CT_POLICY_EVAL_CTX_set_shared_CTLOG_STORE(CT_POLICY_EVAL_CTX *ctx, |
| 100 | CTLOG_STORE *log_store); |
| 101 | |
| 102 | /* |
| 103 | * Gets the time, in milliseconds since the Unix epoch, that will be used as the |
| 104 | * current time when checking whether an SCT was issued in the future. |
| 105 | * Such SCTs will fail validation, as required by RFC6962. |
| 106 | */ |
| 107 | uint64_t CT_POLICY_EVAL_CTX_get_time(const CT_POLICY_EVAL_CTX *ctx); |
| 108 | |
| 109 | /* |
| 110 | * Sets the time to evaluate SCTs against, in milliseconds since the Unix epoch. |
| 111 | * If an SCT's timestamp is after this time, it will be interpreted as having |
| 112 | * been issued in the future. RFC6962 states that "TLS clients MUST reject SCTs |
| 113 | * whose timestamp is in the future", so an SCT will not validate in this case. |
| 114 | */ |
| 115 | void CT_POLICY_EVAL_CTX_set_time(CT_POLICY_EVAL_CTX *ctx, uint64_t time_in_ms); |
| 116 | |
| 117 | /***************** |
| 118 | * SCT functions * |
| 119 | *****************/ |
| 120 | |
| 121 | /* |
| 122 | * Creates a new, blank SCT. |
| 123 | * The caller is responsible for calling SCT_free when finished with the SCT. |
| 124 | */ |
| 125 | SCT *SCT_new(void); |
| 126 | |
| 127 | /* |
| 128 | * Creates a new SCT from some base64-encoded strings. |
| 129 | * The caller is responsible for calling SCT_free when finished with the SCT. |
| 130 | */ |
| 131 | SCT *SCT_new_from_base64(unsigned char version, |
| 132 | const char *logid_base64, |
| 133 | ct_log_entry_type_t entry_type, |
| 134 | uint64_t timestamp, |
| 135 | const char *extensions_base64, |
| 136 | const char *signature_base64); |
| 137 | |
| 138 | /* |
| 139 | * Frees the SCT and the underlying data structures. |
| 140 | */ |
| 141 | void SCT_free(SCT *sct); |
| 142 | |
| 143 | /* |
| 144 | * Free a stack of SCTs, and the underlying SCTs themselves. |
| 145 | * Intended to be compatible with X509V3_EXT_FREE. |
| 146 | */ |
| 147 | void SCT_LIST_free(STACK_OF(SCT) *a); |
| 148 | |
| 149 | /* |
| 150 | * Returns the version of the SCT. |
| 151 | */ |
| 152 | sct_version_t SCT_get_version(const SCT *sct); |
| 153 | |
| 154 | /* |
| 155 | * Set the version of an SCT. |
| 156 | * Returns 1 on success, 0 if the version is unrecognized. |
| 157 | */ |
| 158 | __owur int SCT_set_version(SCT *sct, sct_version_t version); |
| 159 | |
| 160 | /* |
| 161 | * Returns the log entry type of the SCT. |
| 162 | */ |
| 163 | ct_log_entry_type_t SCT_get_log_entry_type(const SCT *sct); |
| 164 | |
| 165 | /* |
| 166 | * Set the log entry type of an SCT. |
| 167 | * Returns 1 on success, 0 otherwise. |
| 168 | */ |
| 169 | __owur int SCT_set_log_entry_type(SCT *sct, ct_log_entry_type_t entry_type); |
| 170 | |
| 171 | /* |
| 172 | * Gets the ID of the log that an SCT came from. |
| 173 | * Ownership of the log ID remains with the SCT. |
| 174 | * Returns the length of the log ID. |
| 175 | */ |
| 176 | size_t SCT_get0_log_id(const SCT *sct, unsigned char **log_id); |
| 177 | |
| 178 | /* |
| 179 | * Set the log ID of an SCT to point directly to the *log_id specified. |
| 180 | * The SCT takes ownership of the specified pointer. |
| 181 | * Returns 1 on success, 0 otherwise. |
| 182 | */ |
| 183 | __owur int SCT_set0_log_id(SCT *sct, unsigned char *log_id, size_t log_id_len); |
| 184 | |
| 185 | /* |
| 186 | * Set the log ID of an SCT. |
| 187 | * This makes a copy of the log_id. |
| 188 | * Returns 1 on success, 0 otherwise. |
| 189 | */ |
| 190 | __owur int SCT_set1_log_id(SCT *sct, const unsigned char *log_id, |
| 191 | size_t log_id_len); |
| 192 | |
| 193 | /* |
| 194 | * Returns the timestamp for the SCT (epoch time in milliseconds). |
| 195 | */ |
| 196 | uint64_t SCT_get_timestamp(const SCT *sct); |
| 197 | |
| 198 | /* |
| 199 | * Set the timestamp of an SCT (epoch time in milliseconds). |
| 200 | */ |
| 201 | void SCT_set_timestamp(SCT *sct, uint64_t timestamp); |
| 202 | |
| 203 | /* |
| 204 | * Return the NID for the signature used by the SCT. |
| 205 | * For CT v1, this will be either NID_sha256WithRSAEncryption or |
| 206 | * NID_ecdsa_with_SHA256 (or NID_undef if incorrect/unset). |
| 207 | */ |
| 208 | int SCT_get_signature_nid(const SCT *sct); |
| 209 | |
| 210 | /* |
| 211 | * Set the signature type of an SCT |
| 212 | * For CT v1, this should be either NID_sha256WithRSAEncryption or |
| 213 | * NID_ecdsa_with_SHA256. |
| 214 | * Returns 1 on success, 0 otherwise. |
| 215 | */ |
| 216 | __owur int SCT_set_signature_nid(SCT *sct, int nid); |
| 217 | |
| 218 | /* |
| 219 | * Set *ext to point to the extension data for the SCT. ext must not be NULL. |
| 220 | * The SCT retains ownership of this pointer. |
| 221 | * Returns length of the data pointed to. |
| 222 | */ |
| 223 | size_t SCT_get0_extensions(const SCT *sct, unsigned char **ext); |
| 224 | |
| 225 | /* |
| 226 | * Set the extensions of an SCT to point directly to the *ext specified. |
| 227 | * The SCT takes ownership of the specified pointer. |
| 228 | */ |
| 229 | void SCT_set0_extensions(SCT *sct, unsigned char *ext, size_t ext_len); |
| 230 | |
| 231 | /* |
| 232 | * Set the extensions of an SCT. |
| 233 | * This takes a copy of the ext. |
| 234 | * Returns 1 on success, 0 otherwise. |
| 235 | */ |
| 236 | __owur int SCT_set1_extensions(SCT *sct, const unsigned char *ext, |
| 237 | size_t ext_len); |
| 238 | |
| 239 | /* |
| 240 | * Set *sig to point to the signature for the SCT. sig must not be NULL. |
| 241 | * The SCT retains ownership of this pointer. |
| 242 | * Returns length of the data pointed to. |
| 243 | */ |
| 244 | size_t SCT_get0_signature(const SCT *sct, unsigned char **sig); |
| 245 | |
| 246 | /* |
| 247 | * Set the signature of an SCT to point directly to the *sig specified. |
| 248 | * The SCT takes ownership of the specified pointer. |
| 249 | */ |
| 250 | void SCT_set0_signature(SCT *sct, unsigned char *sig, size_t sig_len); |
| 251 | |
| 252 | /* |
| 253 | * Set the signature of an SCT to be a copy of the *sig specified. |
| 254 | * Returns 1 on success, 0 otherwise. |
| 255 | */ |
| 256 | __owur int SCT_set1_signature(SCT *sct, const unsigned char *sig, |
| 257 | size_t sig_len); |
| 258 | |
| 259 | /* |
| 260 | * The origin of this SCT, e.g. TLS extension, OCSP response, etc. |
| 261 | */ |
| 262 | sct_source_t SCT_get_source(const SCT *sct); |
| 263 | |
| 264 | /* |
| 265 | * Set the origin of this SCT, e.g. TLS extension, OCSP response, etc. |
| 266 | * Returns 1 on success, 0 otherwise. |
| 267 | */ |
| 268 | __owur int SCT_set_source(SCT *sct, sct_source_t source); |
| 269 | |
| 270 | /* |
| 271 | * Returns a text string describing the validation status of |sct|. |
| 272 | */ |
| 273 | const char *SCT_validation_status_string(const SCT *sct); |
| 274 | |
| 275 | /* |
| 276 | * Pretty-prints an |sct| to |out|. |
| 277 | * It will be indented by the number of spaces specified by |indent|. |
| 278 | * If |logs| is not NULL, it will be used to lookup the CT log that the SCT came |
| 279 | * from, so that the log name can be printed. |
| 280 | */ |
| 281 | void SCT_print(const SCT *sct, BIO *out, int indent, const CTLOG_STORE *logs); |
| 282 | |
| 283 | /* |
| 284 | * Pretty-prints an |sct_list| to |out|. |
| 285 | * It will be indented by the number of spaces specified by |indent|. |
| 286 | * SCTs will be delimited by |separator|. |
| 287 | * If |logs| is not NULL, it will be used to lookup the CT log that each SCT |
| 288 | * came from, so that the log names can be printed. |
| 289 | */ |
| 290 | void SCT_LIST_print(const STACK_OF(SCT) *sct_list, BIO *out, int indent, |
| 291 | const char *separator, const CTLOG_STORE *logs); |
| 292 | |
| 293 | /* |
| 294 | * Gets the last result of validating this SCT. |
| 295 | * If it has not been validated yet, returns SCT_VALIDATION_STATUS_NOT_SET. |
| 296 | */ |
| 297 | sct_validation_status_t SCT_get_validation_status(const SCT *sct); |
| 298 | |
| 299 | /* |
| 300 | * Validates the given SCT with the provided context. |
| 301 | * Sets the "validation_status" field of the SCT. |
| 302 | * Returns 1 if the SCT is valid and the signature verifies. |
| 303 | * Returns 0 if the SCT is invalid or could not be verified. |
| 304 | * Returns -1 if an error occurs. |
| 305 | */ |
| 306 | __owur int SCT_validate(SCT *sct, const CT_POLICY_EVAL_CTX *ctx); |
| 307 | |
| 308 | /* |
| 309 | * Validates the given list of SCTs with the provided context. |
| 310 | * Sets the "validation_status" field of each SCT. |
| 311 | * Returns 1 if there are no invalid SCTs and all signatures verify. |
| 312 | * Returns 0 if at least one SCT is invalid or could not be verified. |
| 313 | * Returns a negative integer if an error occurs. |
| 314 | */ |
| 315 | __owur int SCT_LIST_validate(const STACK_OF(SCT) *scts, |
| 316 | CT_POLICY_EVAL_CTX *ctx); |
| 317 | |
| 318 | |
| 319 | /********************************* |
| 320 | * SCT parsing and serialisation * |
| 321 | *********************************/ |
| 322 | |
| 323 | /* |
| 324 | * Serialize (to TLS format) a stack of SCTs and return the length. |
| 325 | * "a" must not be NULL. |
| 326 | * If "pp" is NULL, just return the length of what would have been serialized. |
| 327 | * If "pp" is not NULL and "*pp" is null, function will allocate a new pointer |
| 328 | * for data that caller is responsible for freeing (only if function returns |
| 329 | * successfully). |
| 330 | * If "pp" is NULL and "*pp" is not NULL, caller is responsible for ensuring |
| 331 | * that "*pp" is large enough to accept all of the serialized data. |
| 332 | * Returns < 0 on error, >= 0 indicating bytes written (or would have been) |
| 333 | * on success. |
| 334 | */ |
| 335 | __owur int i2o_SCT_LIST(const STACK_OF(SCT) *a, unsigned char **pp); |
| 336 | |
| 337 | /* |
| 338 | * Convert TLS format SCT list to a stack of SCTs. |
| 339 | * If "a" or "*a" is NULL, a new stack will be created that the caller is |
| 340 | * responsible for freeing (by calling SCT_LIST_free). |
| 341 | * "**pp" and "*pp" must not be NULL. |
| 342 | * Upon success, "*pp" will point to after the last bytes read, and a stack |
| 343 | * will be returned. |
| 344 | * Upon failure, a NULL pointer will be returned, and the position of "*pp" is |
| 345 | * not defined. |
| 346 | */ |
| 347 | STACK_OF(SCT) *o2i_SCT_LIST(STACK_OF(SCT) **a, const unsigned char **pp, |
| 348 | size_t len); |
| 349 | |
| 350 | /* |
| 351 | * Serialize (to DER format) a stack of SCTs and return the length. |
| 352 | * "a" must not be NULL. |
| 353 | * If "pp" is NULL, just returns the length of what would have been serialized. |
| 354 | * If "pp" is not NULL and "*pp" is null, function will allocate a new pointer |
| 355 | * for data that caller is responsible for freeing (only if function returns |
| 356 | * successfully). |
| 357 | * If "pp" is NULL and "*pp" is not NULL, caller is responsible for ensuring |
| 358 | * that "*pp" is large enough to accept all of the serialized data. |
| 359 | * Returns < 0 on error, >= 0 indicating bytes written (or would have been) |
| 360 | * on success. |
| 361 | */ |
| 362 | __owur int i2d_SCT_LIST(const STACK_OF(SCT) *a, unsigned char **pp); |
| 363 | |
| 364 | /* |
| 365 | * Parses an SCT list in DER format and returns it. |
| 366 | * If "a" or "*a" is NULL, a new stack will be created that the caller is |
| 367 | * responsible for freeing (by calling SCT_LIST_free). |
| 368 | * "**pp" and "*pp" must not be NULL. |
| 369 | * Upon success, "*pp" will point to after the last bytes read, and a stack |
| 370 | * will be returned. |
| 371 | * Upon failure, a NULL pointer will be returned, and the position of "*pp" is |
| 372 | * not defined. |
| 373 | */ |
| 374 | STACK_OF(SCT) *d2i_SCT_LIST(STACK_OF(SCT) **a, const unsigned char **pp, |
| 375 | long len); |
| 376 | |
| 377 | /* |
| 378 | * Serialize (to TLS format) an |sct| and write it to |out|. |
| 379 | * If |out| is null, no SCT will be output but the length will still be returned. |
| 380 | * If |out| points to a null pointer, a string will be allocated to hold the |
| 381 | * TLS-format SCT. It is the responsibility of the caller to free it. |
| 382 | * If |out| points to an allocated string, the TLS-format SCT will be written |
| 383 | * to it. |
| 384 | * The length of the SCT in TLS format will be returned. |
| 385 | */ |
| 386 | __owur int i2o_SCT(const SCT *sct, unsigned char **out); |
| 387 | |
| 388 | /* |
| 389 | * Parses an SCT in TLS format and returns it. |
| 390 | * If |psct| is not null, it will end up pointing to the parsed SCT. If it |
| 391 | * already points to a non-null pointer, the pointer will be free'd. |
| 392 | * |in| should be a pointer to a string containing the TLS-format SCT. |
| 393 | * |in| will be advanced to the end of the SCT if parsing succeeds. |
| 394 | * |len| should be the length of the SCT in |in|. |
| 395 | * Returns NULL if an error occurs. |
| 396 | * If the SCT is an unsupported version, only the SCT's 'sct' and 'sct_len' |
| 397 | * fields will be populated (with |in| and |len| respectively). |
| 398 | */ |
| 399 | SCT *o2i_SCT(SCT **psct, const unsigned char **in, size_t len); |
| 400 | |
| 401 | /******************** |
| 402 | * CT log functions * |
| 403 | ********************/ |
| 404 | |
| 405 | /* |
| 406 | * Creates a new CT log instance with the given |public_key| and |name|. |
| 407 | * Takes ownership of |public_key| but copies |name|. |
| 408 | * Returns NULL if malloc fails or if |public_key| cannot be converted to DER. |
| 409 | * Should be deleted by the caller using CTLOG_free when no longer needed. |
| 410 | */ |
| 411 | CTLOG *CTLOG_new(EVP_PKEY *public_key, const char *name); |
| 412 | |
| 413 | /* |
| 414 | * Creates a new CTLOG instance with the base64-encoded SubjectPublicKeyInfo DER |
| 415 | * in |pkey_base64|. The |name| is a string to help users identify this log. |
| 416 | * Returns 1 on success, 0 on failure. |
| 417 | * Should be deleted by the caller using CTLOG_free when no longer needed. |
| 418 | */ |
| 419 | int CTLOG_new_from_base64(CTLOG ** ct_log, |
| 420 | const char *pkey_base64, const char *name); |
| 421 | |
| 422 | /* |
| 423 | * Deletes a CT log instance and its fields. |
| 424 | */ |
| 425 | void CTLOG_free(CTLOG *log); |
| 426 | |
| 427 | /* Gets the name of the CT log */ |
| 428 | const char *CTLOG_get0_name(const CTLOG *log); |
| 429 | /* Gets the ID of the CT log */ |
| 430 | void CTLOG_get0_log_id(const CTLOG *log, const uint8_t **log_id, |
| 431 | size_t *log_id_len); |
| 432 | /* Gets the public key of the CT log */ |
| 433 | EVP_PKEY *CTLOG_get0_public_key(const CTLOG *log); |
| 434 | |
| 435 | /************************** |
| 436 | * CT log store functions * |
| 437 | **************************/ |
| 438 | |
| 439 | /* |
| 440 | * Creates a new CT log store. |
| 441 | * Should be deleted by the caller using CTLOG_STORE_free when no longer needed. |
| 442 | */ |
| 443 | CTLOG_STORE *CTLOG_STORE_new(void); |
| 444 | |
| 445 | /* |
| 446 | * Deletes a CT log store and all of the CT log instances held within. |
| 447 | */ |
| 448 | void CTLOG_STORE_free(CTLOG_STORE *store); |
| 449 | |
| 450 | /* |
| 451 | * Finds a CT log in the store based on its log ID. |
| 452 | * Returns the CT log, or NULL if no match is found. |
| 453 | */ |
| 454 | const CTLOG *CTLOG_STORE_get0_log_by_id(const CTLOG_STORE *store, |
| 455 | const uint8_t *log_id, |
| 456 | size_t log_id_len); |
| 457 | |
| 458 | /* |
| 459 | * Loads a CT log list into a |store| from a |file|. |
| 460 | * Returns 1 if loading is successful, or 0 otherwise. |
| 461 | */ |
| 462 | __owur int CTLOG_STORE_load_file(CTLOG_STORE *store, const char *file); |
| 463 | |
| 464 | /* |
| 465 | * Loads the default CT log list into a |store|. |
| 466 | * Returns 1 if loading is successful, or 0 otherwise. |
| 467 | */ |
| 468 | __owur int CTLOG_STORE_load_default_file(CTLOG_STORE *store); |
| 469 | |
| 470 | # ifdef __cplusplus |
| 471 | } |
| 472 | # endif |
| 473 | # endif |
| 474 | #endif |