yuezonghe | 824eb0c | 2024-06-27 02:32:26 -0700 | [diff] [blame] | 1 | =pod |
| 2 | |
| 3 | =head1 NAME |
| 4 | |
| 5 | SCT_new, SCT_new_from_base64, SCT_free, SCT_LIST_free, |
| 6 | SCT_get_version, SCT_set_version, |
| 7 | SCT_get_log_entry_type, SCT_set_log_entry_type, |
| 8 | SCT_get0_log_id, SCT_set0_log_id, SCT_set1_log_id, |
| 9 | SCT_get_timestamp, SCT_set_timestamp, |
| 10 | SCT_get_signature_nid, SCT_set_signature_nid, |
| 11 | SCT_get0_signature, SCT_set0_signature, SCT_set1_signature, |
| 12 | SCT_get0_extensions, SCT_set0_extensions, SCT_set1_extensions, |
| 13 | SCT_get_source, SCT_set_source |
| 14 | - A Certificate Transparency Signed Certificate Timestamp |
| 15 | |
| 16 | =head1 SYNOPSIS |
| 17 | |
| 18 | #include <openssl/ct.h> |
| 19 | |
| 20 | typedef enum { |
| 21 | CT_LOG_ENTRY_TYPE_NOT_SET = -1, |
| 22 | CT_LOG_ENTRY_TYPE_X509 = 0, |
| 23 | CT_LOG_ENTRY_TYPE_PRECERT = 1 |
| 24 | } ct_log_entry_type_t; |
| 25 | |
| 26 | typedef enum { |
| 27 | SCT_VERSION_NOT_SET = -1, |
| 28 | SCT_VERSION_V1 = 0 |
| 29 | } sct_version_t; |
| 30 | |
| 31 | typedef enum { |
| 32 | SCT_SOURCE_UNKNOWN, |
| 33 | SCT_SOURCE_TLS_EXTENSION, |
| 34 | SCT_SOURCE_X509V3_EXTENSION, |
| 35 | SCT_SOURCE_OCSP_STAPLED_RESPONSE |
| 36 | } sct_source_t; |
| 37 | |
| 38 | SCT *SCT_new(void); |
| 39 | SCT *SCT_new_from_base64(unsigned char version, |
| 40 | const char *logid_base64, |
| 41 | ct_log_entry_type_t entry_type, |
| 42 | uint64_t timestamp, |
| 43 | const char *extensions_base64, |
| 44 | const char *signature_base64); |
| 45 | |
| 46 | void SCT_free(SCT *sct); |
| 47 | void SCT_LIST_free(STACK_OF(SCT) *a); |
| 48 | |
| 49 | sct_version_t SCT_get_version(const SCT *sct); |
| 50 | int SCT_set_version(SCT *sct, sct_version_t version); |
| 51 | |
| 52 | ct_log_entry_type_t SCT_get_log_entry_type(const SCT *sct); |
| 53 | int SCT_set_log_entry_type(SCT *sct, ct_log_entry_type_t entry_type); |
| 54 | |
| 55 | size_t SCT_get0_log_id(const SCT *sct, unsigned char **log_id); |
| 56 | int SCT_set0_log_id(SCT *sct, unsigned char *log_id, size_t log_id_len); |
| 57 | int SCT_set1_log_id(SCT *sct, const unsigned char *log_id, size_t log_id_len); |
| 58 | |
| 59 | uint64_t SCT_get_timestamp(const SCT *sct); |
| 60 | void SCT_set_timestamp(SCT *sct, uint64_t timestamp); |
| 61 | |
| 62 | int SCT_get_signature_nid(const SCT *sct); |
| 63 | int SCT_set_signature_nid(SCT *sct, int nid); |
| 64 | |
| 65 | size_t SCT_get0_signature(const SCT *sct, unsigned char **sig); |
| 66 | void SCT_set0_signature(SCT *sct, unsigned char *sig, size_t sig_len); |
| 67 | int SCT_set1_signature(SCT *sct, const unsigned char *sig, size_t sig_len); |
| 68 | |
| 69 | size_t SCT_get0_extensions(const SCT *sct, unsigned char **ext); |
| 70 | void SCT_set0_extensions(SCT *sct, unsigned char *ext, size_t ext_len); |
| 71 | int SCT_set1_extensions(SCT *sct, const unsigned char *ext, size_t ext_len); |
| 72 | |
| 73 | sct_source_t SCT_get_source(const SCT *sct); |
| 74 | int SCT_set_source(SCT *sct, sct_source_t source); |
| 75 | |
| 76 | =head1 DESCRIPTION |
| 77 | |
| 78 | Signed Certificate Timestamps (SCTs) are defined by RFC 6962, Section 3.2. |
| 79 | They constitute a promise by a Certificate Transparency (CT) log to publicly |
| 80 | record a certificate. By cryptographically verifying that a log did indeed issue |
| 81 | an SCT, some confidence can be gained that the certificate is publicly known. |
| 82 | |
| 83 | An internal representation of an SCT can be created in one of two ways. |
| 84 | The first option is to create a blank SCT, using SCT_new(), and then populate |
| 85 | it using: |
| 86 | |
| 87 | =over 2 |
| 88 | |
| 89 | =item * |
| 90 | |
| 91 | SCT_set_version() to set the SCT version. |
| 92 | |
| 93 | Only SCT_VERSION_V1 is currently supported. |
| 94 | |
| 95 | =item * |
| 96 | |
| 97 | SCT_set_log_entry_type() to set the type of certificate the SCT was issued for: |
| 98 | |
| 99 | B<CT_LOG_ENTRY_TYPE_X509> for a normal certificate. |
| 100 | B<CT_LOG_ENTRY_TYPE_PRECERT> for a pre-certificate. |
| 101 | |
| 102 | =item * |
| 103 | |
| 104 | SCT_set0_log_id() or SCT_set1_log_id() to set the LogID of the CT log that the SCT came from. |
| 105 | |
| 106 | The former takes ownership, whereas the latter makes a copy. |
| 107 | See RFC 6962, Section 3.2 for the definition of LogID. |
| 108 | |
| 109 | =item * |
| 110 | |
| 111 | SCT_set_timestamp() to set the time the SCT was issued (epoch time in milliseconds). |
| 112 | |
| 113 | =item * |
| 114 | |
| 115 | SCT_set_signature_nid() to set the NID of the signature. |
| 116 | |
| 117 | =item * |
| 118 | |
| 119 | SCT_set0_signature() or SCT_set1_signature() to set the raw signature value. |
| 120 | |
| 121 | The former takes ownership, whereas the latter makes a copy. |
| 122 | |
| 123 | =item * |
| 124 | |
| 125 | SCT_set0_extensions() or B<SCT_set1_extensions> to provide SCT extensions. |
| 126 | |
| 127 | The former takes ownership, whereas the latter makes a copy. |
| 128 | |
| 129 | =back |
| 130 | |
| 131 | Alternatively, the SCT can be pre-populated from the following data using |
| 132 | SCT_new_from_base64(): |
| 133 | |
| 134 | =over 2 |
| 135 | |
| 136 | =item * |
| 137 | |
| 138 | The SCT version (only SCT_VERSION_V1 is currently supported). |
| 139 | |
| 140 | =item * |
| 141 | |
| 142 | The LogID (see RFC 6962, Section 3.2), base64 encoded. |
| 143 | |
| 144 | =item * |
| 145 | |
| 146 | The type of certificate the SCT was issued for: |
| 147 | B<CT_LOG_ENTRY_TYPE_X509> for a normal certificate. |
| 148 | B<CT_LOG_ENTRY_TYPE_PRECERT> for a pre-certificate. |
| 149 | |
| 150 | =item * |
| 151 | |
| 152 | The time that the SCT was issued (epoch time in milliseconds). |
| 153 | |
| 154 | =item * |
| 155 | |
| 156 | The SCT extensions, base64 encoded. |
| 157 | |
| 158 | =item * |
| 159 | |
| 160 | The SCT signature, base64 encoded. |
| 161 | |
| 162 | =back |
| 163 | |
| 164 | SCT_set_source() can be used to record where the SCT was found |
| 165 | (TLS extension, X.509 certificate extension or OCSP response). This is not |
| 166 | required for verifying the SCT. |
| 167 | |
| 168 | =head1 NOTES |
| 169 | |
| 170 | Some of the setters return int, instead of void. These will all return 1 on |
| 171 | success, 0 on failure. They will not make changes on failure. |
| 172 | |
| 173 | All of the setters will reset the validation status of the SCT to |
| 174 | SCT_VALIDATION_STATUS_NOT_SET (see L<SCT_validate(3)>). |
| 175 | |
| 176 | SCT_set_source() will call SCT_set_log_entry_type() if the type of |
| 177 | certificate the SCT was issued for can be inferred from where the SCT was found. |
| 178 | For example, an SCT found in an X.509 extension must have been issued for a pre- |
| 179 | certificate. |
| 180 | |
| 181 | SCT_set_source() will not refuse unknown values. |
| 182 | |
| 183 | =head1 RETURN VALUES |
| 184 | |
| 185 | SCT_set_version() returns 1 if the specified version is supported, 0 otherwise. |
| 186 | |
| 187 | SCT_set_log_entry_type() returns 1 if the specified log entry type is supported, 0 otherwise. |
| 188 | |
| 189 | SCT_set0_log_id() and B<SCT_set1_log_id> return 1 if the specified LogID is a |
| 190 | valid SHA-256 hash, 0 otherwise. Additionally, B<SCT_set1_log_id> returns 0 if |
| 191 | malloc fails. |
| 192 | |
| 193 | B<SCT_set_signature_nid> returns 1 if the specified NID is supported, 0 otherwise. |
| 194 | |
| 195 | B<SCT_set1_extensions> and B<SCT_set1_signature> return 1 if the supplied buffer |
| 196 | is copied successfully, 0 otherwise (i.e. if malloc fails). |
| 197 | |
| 198 | B<SCT_set_source> returns 1 on success, 0 otherwise. |
| 199 | |
| 200 | =head1 SEE ALSO |
| 201 | |
| 202 | L<ct(7)>, |
| 203 | L<SCT_validate(3)>, |
| 204 | L<OBJ_nid2obj(3)> |
| 205 | |
| 206 | =head1 HISTORY |
| 207 | |
| 208 | These functions were added in OpenSSL 1.1.0. |
| 209 | |
| 210 | =head1 COPYRIGHT |
| 211 | |
| 212 | Copyright 2016-2017 The OpenSSL Project Authors. All Rights Reserved. |
| 213 | |
| 214 | Licensed under the OpenSSL license (the "License"). You may not use |
| 215 | this file except in compliance with the License. You can obtain a copy |
| 216 | in the file LICENSE in the source distribution or at |
| 217 | L<https://www.openssl.org/source/license.html>. |
| 218 | |
| 219 | =cut |