/* $OpenBSD: ct.h,v 1.8 2024/08/08 23:50:29 tb Exp $ */ /* * Public API for Certificate Transparency (CT). * Written by Rob Percival (robpercival@google.com) for the OpenSSL project. */ /* ==================================================================== * Copyright (c) 2016 The OpenSSL Project. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * 3. All advertising materials mentioning features or use of this * software must display the following acknowledgment: * "This product includes software developed by the OpenSSL Project * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)" * * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to * endorse or promote products derived from this software without * prior written permission. For written permission, please contact * licensing@OpenSSL.org. * * 5. Products derived from this software may not be called "OpenSSL" * nor may "OpenSSL" appear in their names without prior written * permission of the OpenSSL Project. * * 6. Redistributions of any form whatsoever must retain the following * acknowledgment: * "This product includes software developed by the OpenSSL Project * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)" * * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED * OF THE POSSIBILITY OF SUCH DAMAGE. * ==================================================================== */ #ifndef HEADER_CT_H #define HEADER_CT_H #include #ifndef OPENSSL_NO_CT #include #include #include #ifdef __cplusplus extern "C" { #endif /* Minimum RSA key size, from RFC6962 */ #define SCT_MIN_RSA_BITS 2048 /* All hashes are SHA256 in v1 of Certificate Transparency */ #define CT_V1_HASHLEN SHA256_DIGEST_LENGTH typedef enum { CT_LOG_ENTRY_TYPE_NOT_SET = -1, CT_LOG_ENTRY_TYPE_X509 = 0, CT_LOG_ENTRY_TYPE_PRECERT = 1 } ct_log_entry_type_t; typedef enum { SCT_VERSION_NOT_SET = -1, SCT_VERSION_V1 = 0 } sct_version_t; typedef enum { SCT_SOURCE_UNKNOWN, SCT_SOURCE_TLS_EXTENSION, SCT_SOURCE_X509V3_EXTENSION, SCT_SOURCE_OCSP_STAPLED_RESPONSE } sct_source_t; typedef enum { SCT_VALIDATION_STATUS_NOT_SET, SCT_VALIDATION_STATUS_UNKNOWN_LOG, SCT_VALIDATION_STATUS_VALID, SCT_VALIDATION_STATUS_INVALID, SCT_VALIDATION_STATUS_UNVERIFIED, SCT_VALIDATION_STATUS_UNKNOWN_VERSION } sct_validation_status_t; DECLARE_STACK_OF(SCT) DECLARE_STACK_OF(CTLOG) /****************************************** * CT policy evaluation context functions * ******************************************/ /* * Creates a new, empty policy evaluation context. * The caller is responsible for calling CT_POLICY_EVAL_CTX_free when finished * with the CT_POLICY_EVAL_CTX. */ CT_POLICY_EVAL_CTX *CT_POLICY_EVAL_CTX_new(void); /* Deletes a policy evaluation context and anything it owns. */ void CT_POLICY_EVAL_CTX_free(CT_POLICY_EVAL_CTX *ctx); /* Gets the peer certificate that the SCTs are for */ X509 *CT_POLICY_EVAL_CTX_get0_cert(const CT_POLICY_EVAL_CTX *ctx); /* * Sets the certificate associated with the received SCTs. * Increments the reference count of cert. * Returns 1 on success, 0 otherwise. */ int CT_POLICY_EVAL_CTX_set1_cert(CT_POLICY_EVAL_CTX *ctx, X509 *cert); /* Gets the issuer of the aforementioned certificate */ X509 *CT_POLICY_EVAL_CTX_get0_issuer(const CT_POLICY_EVAL_CTX *ctx); /* * Sets the issuer of the certificate associated with the received SCTs. * Increments the reference count of issuer. * Returns 1 on success, 0 otherwise. */ int CT_POLICY_EVAL_CTX_set1_issuer(CT_POLICY_EVAL_CTX *ctx, X509 *issuer); /* Gets the CT logs that are trusted sources of SCTs */ const CTLOG_STORE *CT_POLICY_EVAL_CTX_get0_log_store(const CT_POLICY_EVAL_CTX *ctx); /* Sets the log store that is in use. It must outlive the CT_POLICY_EVAL_CTX. */ void CT_POLICY_EVAL_CTX_set_shared_CTLOG_STORE(CT_POLICY_EVAL_CTX *ctx, CTLOG_STORE *log_store); /* * Gets the time, in milliseconds since the Unix epoch, that will be used as the * current time when checking whether an SCT was issued in the future. * Such SCTs will fail validation, as required by RFC6962. */ uint64_t CT_POLICY_EVAL_CTX_get_time(const CT_POLICY_EVAL_CTX *ctx); /* * Sets the time to evaluate SCTs against, in milliseconds since the Unix epoch. * If an SCT's timestamp is after this time, it will be interpreted as having * been issued in the future. RFC6962 states that "TLS clients MUST reject SCTs * whose timestamp is in the future", so an SCT will not validate in this case. */ void CT_POLICY_EVAL_CTX_set_time(CT_POLICY_EVAL_CTX *ctx, uint64_t time_in_ms); /***************** * SCT functions * *****************/ /* * Creates a new, blank SCT. * The caller is responsible for calling SCT_free when finished with the SCT. */ SCT *SCT_new(void); /* * Creates a new SCT from some base64-encoded strings. * The caller is responsible for calling SCT_free when finished with the SCT. */ SCT *SCT_new_from_base64(unsigned char version, const char *logid_base64, ct_log_entry_type_t entry_type, uint64_t timestamp, const char *extensions_base64, const char *signature_base64); /* * Frees the SCT and the underlying data structures. */ void SCT_free(SCT *sct); /* * Free a stack of SCTs, and the underlying SCTs themselves. * Intended to be compatible with X509V3_EXT_FREE. */ void SCT_LIST_free(STACK_OF(SCT) *a); /* * Returns the version of the SCT. */ sct_version_t SCT_get_version(const SCT *sct); /* * Set the version of an SCT. * Returns 1 on success, 0 if the version is unrecognized. */ int SCT_set_version(SCT *sct, sct_version_t version); /* * Returns the log entry type of the SCT. */ ct_log_entry_type_t SCT_get_log_entry_type(const SCT *sct); /* * Set the log entry type of an SCT. * Returns 1 on success, 0 otherwise. */ int SCT_set_log_entry_type(SCT *sct, ct_log_entry_type_t entry_type); /* * Gets the ID of the log that an SCT came from. * Ownership of the log ID remains with the SCT. * Returns the length of the log ID. */ size_t SCT_get0_log_id(const SCT *sct, unsigned char **log_id); /* * Set the log ID of an SCT to point directly to the *log_id specified. * The SCT takes ownership of the specified pointer. * Returns 1 on success, 0 otherwise. */ int SCT_set0_log_id(SCT *sct, unsigned char *log_id, size_t log_id_len); /* * Set the log ID of an SCT. * This makes a copy of the log_id. * Returns 1 on success, 0 otherwise. */ int SCT_set1_log_id(SCT *sct, const unsigned char *log_id, size_t log_id_len); /* * Returns the timestamp for the SCT (epoch time in milliseconds). */ uint64_t SCT_get_timestamp(const SCT *sct); /* * Set the timestamp of an SCT (epoch time in milliseconds). */ void SCT_set_timestamp(SCT *sct, uint64_t timestamp); /* * Return the NID for the signature used by the SCT. * For CT v1, this will be either NID_sha256WithRSAEncryption or * NID_ecdsa_with_SHA256 (or NID_undef if incorrect/unset). */ int SCT_get_signature_nid(const SCT *sct); /* * Set the signature type of an SCT * For CT v1, this should be either NID_sha256WithRSAEncryption or * NID_ecdsa_with_SHA256. * Returns 1 on success, 0 otherwise. */ int SCT_set_signature_nid(SCT *sct, int nid); /* * Set *ext to point to the extension data for the SCT. ext must not be NULL. * The SCT retains ownership of this pointer. * Returns length of the data pointed to. */ size_t SCT_get0_extensions(const SCT *sct, unsigned char **ext); /* * Set the extensions of an SCT to point directly to the *ext specified. * The SCT takes ownership of the specified pointer. */ void SCT_set0_extensions(SCT *sct, unsigned char *ext, size_t ext_len); /* * Set the extensions of an SCT. * This takes a copy of the ext. * Returns 1 on success, 0 otherwise. */ int SCT_set1_extensions(SCT *sct, const unsigned char *ext, size_t ext_len); /* * Set *sig to point to the signature for the SCT. sig must not be NULL. * The SCT retains ownership of this pointer. * Returns length of the data pointed to. */ size_t SCT_get0_signature(const SCT *sct, unsigned char **sig); /* * Set the signature of an SCT to point directly to the *sig specified. * The SCT takes ownership of the specified pointer. */ void SCT_set0_signature(SCT *sct, unsigned char *sig, size_t sig_len); /* * Set the signature of an SCT to be a copy of the *sig specified. * Returns 1 on success, 0 otherwise. */ int SCT_set1_signature(SCT *sct, const unsigned char *sig, size_t sig_len); /* * The origin of this SCT, e.g. TLS extension, OCSP response, etc. */ sct_source_t SCT_get_source(const SCT *sct); /* * Set the origin of this SCT, e.g. TLS extension, OCSP response, etc. * Returns 1 on success, 0 otherwise. */ int SCT_set_source(SCT *sct, sct_source_t source); /* * Returns a text string describing the validation status of |sct|. */ const char *SCT_validation_status_string(const SCT *sct); /* * Pretty-prints an |sct| to |out|. * It will be indented by the number of spaces specified by |indent|. * If |logs| is not NULL, it will be used to lookup the CT log that the SCT came * from, so that the log name can be printed. */ void SCT_print(const SCT *sct, BIO *out, int indent, const CTLOG_STORE *logs); /* * Pretty-prints an |sct_list| to |out|. * It will be indented by the number of spaces specified by |indent|. * SCTs will be delimited by |separator|. * If |logs| is not NULL, it will be used to lookup the CT log that each SCT * came from, so that the log names can be printed. */ void SCT_LIST_print(const STACK_OF(SCT) *sct_list, BIO *out, int indent, const char *separator, const CTLOG_STORE *logs); /* * Gets the last result of validating this SCT. * If it has not been validated yet, returns SCT_VALIDATION_STATUS_NOT_SET. */ sct_validation_status_t SCT_get_validation_status(const SCT *sct); /* * Validates the given SCT with the provided context. * Sets the "validation_status" field of the SCT. * Returns 1 if the SCT is valid and the signature verifies. * Returns 0 if the SCT is invalid or could not be verified. * Returns -1 if an error occurs. */ int SCT_validate(SCT *sct, const CT_POLICY_EVAL_CTX *ctx); /* * Validates the given list of SCTs with the provided context. * Sets the "validation_status" field of each SCT. * Returns 1 if there are no invalid SCTs and all signatures verify. * Returns 0 if at least one SCT is invalid or could not be verified. * Returns a negative integer if an error occurs. */ int SCT_LIST_validate(const STACK_OF(SCT) *scts, CT_POLICY_EVAL_CTX *ctx); /********************************* * SCT parsing and serialisation * *********************************/ /* * Serialize (to TLS format) a stack of SCTs and return the length. * "a" must not be NULL. * If "pp" is NULL, just return the length of what would have been serialized. * If "pp" is not NULL and "*pp" is null, function will allocate a new pointer * for data that caller is responsible for freeing (only if function returns * successfully). * If "pp" is NULL and "*pp" is not NULL, caller is responsible for ensuring * that "*pp" is large enough to accept all of the serialized data. * Returns < 0 on error, >= 0 indicating bytes written (or would have been) * on success. */ int i2o_SCT_LIST(const STACK_OF(SCT) *a, unsigned char **pp); /* * Convert TLS format SCT list to a stack of SCTs. * If "a" or "*a" is NULL, a new stack will be created that the caller is * responsible for freeing (by calling SCT_LIST_free). * "**pp" and "*pp" must not be NULL. * Upon success, "*pp" will point to after the last bytes read, and a stack * will be returned. * Upon failure, a NULL pointer will be returned, and the position of "*pp" is * not defined. */ STACK_OF(SCT) *o2i_SCT_LIST(STACK_OF(SCT) **a, const unsigned char **pp, size_t len); /* * Serialize (to DER format) a stack of SCTs and return the length. * "a" must not be NULL. * If "pp" is NULL, just returns the length of what would have been serialized. * If "pp" is not NULL and "*pp" is null, function will allocate a new pointer * for data that caller is responsible for freeing (only if function returns * successfully). * If "pp" is NULL and "*pp" is not NULL, caller is responsible for ensuring * that "*pp" is large enough to accept all of the serialized data. * Returns < 0 on error, >= 0 indicating bytes written (or would have been) * on success. */ int i2d_SCT_LIST(const STACK_OF(SCT) *a, unsigned char **pp); /* * Parses an SCT list in DER format and returns it. * If "a" or "*a" is NULL, a new stack will be created that the caller is * responsible for freeing (by calling SCT_LIST_free). * "**pp" and "*pp" must not be NULL. * Upon success, "*pp" will point to after the last bytes read, and a stack * will be returned. * Upon failure, a NULL pointer will be returned, and the position of "*pp" is * not defined. */ STACK_OF(SCT) *d2i_SCT_LIST(STACK_OF(SCT) **a, const unsigned char **pp, long len); /* * Serialize (to TLS format) an |sct| and write it to |out|. * If |out| is null, no SCT will be output but the length will still be returned. * If |out| points to a null pointer, a string will be allocated to hold the * TLS-format SCT. It is the responsibility of the caller to free it. * If |out| points to an allocated string, the TLS-format SCT will be written * to it. * The length of the SCT in TLS format will be returned. */ int i2o_SCT(const SCT *sct, unsigned char **out); /* * Parses an SCT in TLS format and returns it. * If |psct| is not null, it will end up pointing to the parsed SCT. If it * already points to a non-null pointer, the pointer will be free'd. * |in| should be a pointer to a string containing the TLS-format SCT. * |in| will be advanced to the end of the SCT if parsing succeeds. * |len| should be the length of the SCT in |in|. * Returns NULL if an error occurs. * If the SCT is an unsupported version, only the SCT's 'sct' and 'sct_len' * fields will be populated (with |in| and |len| respectively). */ SCT *o2i_SCT(SCT **psct, const unsigned char **in, size_t len); /******************** * CT log functions * ********************/ /* * Creates a new CT log instance with the given |public_key| and |name|. * Takes ownership of |public_key| but copies |name|. * Returns NULL if malloc fails or if |public_key| cannot be converted to DER. * Should be deleted by the caller using CTLOG_free when no longer needed. */ CTLOG *CTLOG_new(EVP_PKEY *public_key, const char *name); /* * Creates a new CTLOG instance with the base64-encoded SubjectPublicKeyInfo DER * in |pkey_base64|. The |name| is a string to help users identify this log. * Returns 1 on success, 0 on failure. * Should be deleted by the caller using CTLOG_free when no longer needed. */ int CTLOG_new_from_base64(CTLOG **ct_log, const char *pkey_base64, const char *name); /* * Deletes a CT log instance and its fields. */ void CTLOG_free(CTLOG *log); /* Gets the name of the CT log */ const char *CTLOG_get0_name(const CTLOG *log); /* Gets the ID of the CT log */ void CTLOG_get0_log_id(const CTLOG *log, const uint8_t **log_id, size_t *log_id_len); /* Gets the public key of the CT log */ EVP_PKEY *CTLOG_get0_public_key(const CTLOG *log); /************************** * CT log store functions * **************************/ /* * Creates a new CT log store. * Should be deleted by the caller using CTLOG_STORE_free when no longer needed. */ CTLOG_STORE *CTLOG_STORE_new(void); /* * Deletes a CT log store and all of the CT log instances held within. */ void CTLOG_STORE_free(CTLOG_STORE *store); /* * Finds a CT log in the store based on its log ID. * Returns the CT log, or NULL if no match is found. */ const CTLOG *CTLOG_STORE_get0_log_by_id(const CTLOG_STORE *store, const uint8_t *log_id, size_t log_id_len); /* * Loads a CT log list into a |store| from a |file|. * Returns 1 if loading is successful, or 0 otherwise. */ int CTLOG_STORE_load_file(CTLOG_STORE *store, const char *file); /* * Loads the default CT log list into a |store|. * Returns 1 if loading is successful, or 0 otherwise. */ int CTLOG_STORE_load_default_file(CTLOG_STORE *store); int ERR_load_CT_strings(void); /* * CT function codes. */ # define CT_F_CTLOG_NEW 117 # define CT_F_CTLOG_NEW_FROM_BASE64 118 # define CT_F_CTLOG_NEW_FROM_CONF 119 # define CT_F_CTLOG_STORE_LOAD_CTX_NEW 122 # define CT_F_CTLOG_STORE_LOAD_FILE 123 # define CT_F_CTLOG_STORE_LOAD_LOG 130 # define CT_F_CTLOG_STORE_NEW 131 # define CT_F_CT_BASE64_DECODE 124 # define CT_F_CT_POLICY_EVAL_CTX_NEW 133 # define CT_F_CT_V1_LOG_ID_FROM_PKEY 125 # define CT_F_I2O_SCT 107 # define CT_F_I2O_SCT_LIST 108 # define CT_F_I2O_SCT_SIGNATURE 109 # define CT_F_O2I_SCT 110 # define CT_F_O2I_SCT_LIST 111 # define CT_F_O2I_SCT_SIGNATURE 112 # define CT_F_SCT_CTX_NEW 126 # define CT_F_SCT_CTX_VERIFY 128 # define CT_F_SCT_NEW 100 # define CT_F_SCT_NEW_FROM_BASE64 127 # define CT_F_SCT_SET0_LOG_ID 101 # define CT_F_SCT_SET1_EXTENSIONS 114 # define CT_F_SCT_SET1_LOG_ID 115 # define CT_F_SCT_SET1_SIGNATURE 116 # define CT_F_SCT_SET_LOG_ENTRY_TYPE 102 # define CT_F_SCT_SET_SIGNATURE_NID 103 # define CT_F_SCT_SET_VERSION 104 /* * CT reason codes. */ # define CT_R_BASE64_DECODE_ERROR 108 # define CT_R_INVALID_LOG_ID_LENGTH 100 # define CT_R_LOG_CONF_INVALID 109 # define CT_R_LOG_CONF_INVALID_KEY 110 # define CT_R_LOG_CONF_MISSING_DESCRIPTION 111 # define CT_R_LOG_CONF_MISSING_KEY 112 # define CT_R_LOG_KEY_INVALID 113 # define CT_R_SCT_FUTURE_TIMESTAMP 116 # define CT_R_SCT_INVALID 104 # define CT_R_SCT_INVALID_SIGNATURE 107 # define CT_R_SCT_LIST_INVALID 105 # define CT_R_SCT_LOG_ID_MISMATCH 114 # define CT_R_SCT_NOT_SET 106 # define CT_R_SCT_UNSUPPORTED_VERSION 115 # define CT_R_UNRECOGNIZED_SIGNATURE_NID 101 # define CT_R_UNSUPPORTED_ENTRY_TYPE 102 # define CT_R_UNSUPPORTED_VERSION 103 #ifdef __cplusplus } #endif #endif #endif