1 /** 2 * \file pkcs7.h 3 * 4 * \brief PKCS7 generic defines and structures 5 * https://tools.ietf.org/html/rfc2315 6 */ 7 /* 8 * Copyright The Mbed TLS Contributors 9 * SPDX-License-Identifier: Apache-2.0 10 * 11 * Licensed under the Apache License, Version 2.0 (the "License"); you may 12 * not use this file except in compliance with the License. 13 * You may obtain a copy of the License at 14 * 15 * http://www.apache.org/licenses/LICENSE-2.0 16 * 17 * Unless required by applicable law or agreed to in writing, software 18 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT 19 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 20 * See the License for the specific language governing permissions and 21 * limitations under the License. 22 */ 23 24 /** 25 * This feature is a work in progress and not ready for production. The API may 26 * change. Furthermore, please note that the implementation has only been 27 * validated with well-formed inputs, not yet with untrusted inputs (which is 28 * almost always the case in practice). 29 * 30 * Note: For the time being, this implementation of the PKCS7 cryptographic 31 * message syntax is a partial implementation of RFC 2315. 32 * Differences include: 33 * - The RFC specifies 6 different content types. The only type currently 34 * supported in Mbed TLS is the signed data content type. 35 * - The only supported PKCS7 Signed Data syntax version is version 1 36 * - The RFC specifies support for BER. This implementation is limited to 37 * DER only. 38 * - The RFC specifies that multiple digest algorithms can be specified 39 * in the Signed Data type. Only one digest algorithm is supported in Mbed TLS. 40 * - The RFC specifies the Signed Data type can contain multiple X509 or PKCS6 41 * certificates. In Mbed TLS, this list can only contain 0 or 1 certificates 42 * and they must be in X509 format. 43 * - The RFC specifies the Signed Data type can contain 44 * certificate-revocation lists (crls). This implementation has no support 45 * for crls so it is assumed to be an empty list. 46 * - The RFC allows for SignerInfo structure to optionally contain 47 * unauthenticatedAttributes and authenticatedAttributes. In Mbed TLS it is 48 * assumed these fields are empty. 49 */ 50 51 #ifndef MBEDTLS_PKCS7_H 52 #define MBEDTLS_PKCS7_H 53 54 #include "mbedtls/private_access.h" 55 56 #include "mbedtls/build_info.h" 57 58 #include "mbedtls/asn1.h" 59 #include "mbedtls/x509.h" 60 #include "mbedtls/x509_crt.h" 61 62 /** 63 * \name PKCS7 Module Error codes 64 * \{ 65 */ 66 #define MBEDTLS_ERR_PKCS7_INVALID_FORMAT -0x5300 /**< The format is invalid, e.g. different type expected. */ 67 #define MBEDTLS_ERR_PKCS7_FEATURE_UNAVAILABLE -0x5380 /**< Unavailable feature, e.g. anything other than signed data. */ 68 #define MBEDTLS_ERR_PKCS7_INVALID_VERSION -0x5400 /**< The PKCS7 version element is invalid or cannot be parsed. */ 69 #define MBEDTLS_ERR_PKCS7_INVALID_CONTENT_INFO -0x5480 /**< The PKCS7 content info invalid or cannot be parsed. */ 70 #define MBEDTLS_ERR_PKCS7_INVALID_ALG -0x5500 /**< The algorithm tag or value is invalid or cannot be parsed. */ 71 #define MBEDTLS_ERR_PKCS7_INVALID_CERT -0x5580 /**< The certificate tag or value is invalid or cannot be parsed. */ 72 #define MBEDTLS_ERR_PKCS7_INVALID_SIGNATURE -0x5600 /**< Error parsing the signature */ 73 #define MBEDTLS_ERR_PKCS7_INVALID_SIGNER_INFO -0x5680 /**< Error parsing the signer's info */ 74 #define MBEDTLS_ERR_PKCS7_BAD_INPUT_DATA -0x5700 /**< Input invalid. */ 75 #define MBEDTLS_ERR_PKCS7_ALLOC_FAILED -0x5780 /**< Allocation of memory failed. */ 76 #define MBEDTLS_ERR_PKCS7_VERIFY_FAIL -0x5800 /**< Verification Failed */ 77 #define MBEDTLS_ERR_PKCS7_CERT_DATE_INVALID -0x5880 /**< The PKCS7 date issued/expired dates are invalid */ 78 /* \} name */ 79 80 /** 81 * \name PKCS7 Supported Version 82 * \{ 83 */ 84 #define MBEDTLS_PKCS7_SUPPORTED_VERSION 0x01 85 /* \} name */ 86 87 #ifdef __cplusplus 88 extern "C" { 89 #endif 90 91 /** 92 * Type-length-value structure that allows for ASN1 using DER. 93 */ 94 typedef mbedtls_asn1_buf mbedtls_pkcs7_buf; 95 96 /** 97 * Container for ASN1 named information objects. 98 * It allows for Relative Distinguished Names (e.g. cn=localhost,ou=code,etc.). 99 */ 100 typedef mbedtls_asn1_named_data mbedtls_pkcs7_name; 101 102 /** 103 * Container for a sequence of ASN.1 items 104 */ 105 typedef mbedtls_asn1_sequence mbedtls_pkcs7_sequence; 106 107 /** 108 * PKCS7 types 109 */ 110 typedef enum { 111 MBEDTLS_PKCS7_NONE=0, 112 MBEDTLS_PKCS7_DATA, 113 MBEDTLS_PKCS7_SIGNED_DATA, 114 MBEDTLS_PKCS7_ENVELOPED_DATA, 115 MBEDTLS_PKCS7_SIGNED_AND_ENVELOPED_DATA, 116 MBEDTLS_PKCS7_DIGESTED_DATA, 117 MBEDTLS_PKCS7_ENCRYPTED_DATA, 118 } 119 mbedtls_pkcs7_type; 120 121 /** 122 * Structure holding PKCS7 signer info 123 */ 124 typedef struct mbedtls_pkcs7_signer_info 125 { 126 int MBEDTLS_PRIVATE(version); 127 mbedtls_x509_buf MBEDTLS_PRIVATE(serial); 128 mbedtls_x509_name MBEDTLS_PRIVATE(issuer); 129 mbedtls_x509_buf MBEDTLS_PRIVATE(issuer_raw); 130 mbedtls_x509_buf MBEDTLS_PRIVATE(alg_identifier); 131 mbedtls_x509_buf MBEDTLS_PRIVATE(sig_alg_identifier); 132 mbedtls_x509_buf MBEDTLS_PRIVATE(sig); 133 struct mbedtls_pkcs7_signer_info *MBEDTLS_PRIVATE(next); 134 } 135 mbedtls_pkcs7_signer_info; 136 137 /** 138 * Structure holding attached data as part of PKCS7 signed data format 139 */ 140 typedef struct mbedtls_pkcs7_data 141 { 142 mbedtls_pkcs7_buf MBEDTLS_PRIVATE(oid); 143 mbedtls_pkcs7_buf MBEDTLS_PRIVATE(data); 144 } 145 mbedtls_pkcs7_data; 146 147 /** 148 * Structure holding the signed data section 149 */ 150 typedef struct mbedtls_pkcs7_signed_data 151 { 152 int MBEDTLS_PRIVATE(version); 153 mbedtls_pkcs7_buf MBEDTLS_PRIVATE(digest_alg_identifiers); 154 struct mbedtls_pkcs7_data MBEDTLS_PRIVATE(content); 155 int MBEDTLS_PRIVATE(no_of_certs); 156 mbedtls_x509_crt MBEDTLS_PRIVATE(certs); 157 int MBEDTLS_PRIVATE(no_of_crls); 158 mbedtls_x509_crl MBEDTLS_PRIVATE(crl); 159 int MBEDTLS_PRIVATE(no_of_signers); 160 mbedtls_pkcs7_signer_info MBEDTLS_PRIVATE(signers); 161 } 162 mbedtls_pkcs7_signed_data; 163 164 /** 165 * Structure holding PKCS7 structure, only signed data for now 166 */ 167 typedef struct mbedtls_pkcs7 168 { 169 mbedtls_pkcs7_buf MBEDTLS_PRIVATE(raw); 170 mbedtls_pkcs7_buf MBEDTLS_PRIVATE(content_type_oid); 171 mbedtls_pkcs7_signed_data MBEDTLS_PRIVATE(signed_data); 172 } 173 mbedtls_pkcs7; 174 175 /** 176 * \brief Initialize pkcs7 structure. 177 * 178 * \param pkcs7 pkcs7 structure. 179 */ 180 void mbedtls_pkcs7_init( mbedtls_pkcs7 *pkcs7 ); 181 182 /** 183 * \brief Parse a single DER formatted pkcs7 content. 184 * 185 * \param pkcs7 The pkcs7 structure to be filled by parser for the output. 186 * \param buf The buffer holding the DER encoded pkcs7. 187 * \param buflen The size in bytes of \p buf. 188 * 189 * \note This function makes an internal copy of the PKCS7 buffer 190 * \p buf. In particular, \p buf may be destroyed or reused 191 * after this call returns. 192 * 193 * \return The \c mbedtls_pkcs7_type of \p buf, if successful. 194 * \return A negative error code on failure. 195 */ 196 int mbedtls_pkcs7_parse_der( mbedtls_pkcs7 *pkcs7, const unsigned char *buf, 197 const size_t buflen ); 198 199 /** 200 * \brief Verification of PKCS7 signature against a caller-supplied 201 * certificate. 202 * 203 * For each signer in the PKCS structure, this function computes 204 * a signature over the supplied data, using the supplied 205 * certificate and the same digest algorithm as specified by the 206 * signer. It then compares this signature against the 207 * signer's signature; verification succeeds if any comparison 208 * matches. 209 * 210 * This function does not use the certificates held within the 211 * PKCS7 structure itself. 212 * 213 * \param pkcs7 PKCS7 structure containing signature. 214 * \param cert Certificate containing key to verify signature. 215 * \param data Plain data on which signature has to be verified. 216 * \param datalen Length of the data. 217 * 218 * \note This function internally calculates the hash on the supplied 219 * plain data for signature verification. 220 * 221 * \return 0 if the signature verifies, or a negative error code on failure. 222 */ 223 int mbedtls_pkcs7_signed_data_verify( mbedtls_pkcs7 *pkcs7, 224 const mbedtls_x509_crt *cert, 225 const unsigned char *data, 226 size_t datalen ); 227 228 /** 229 * \brief Verification of PKCS7 signature against a caller-supplied 230 * certificate. 231 * 232 * For each signer in the PKCS structure, this function computes 233 * a signature over the supplied hash, using the supplied 234 * certificate and the same digest algorithm as specified by the 235 * signer. It then compares this signature against the 236 * signer's signature; verification succeeds if any comparison 237 * matches. 238 * 239 * This function does not use the certificates held within the 240 * PKCS7 structure itself. 241 * 242 * \param pkcs7 PKCS7 structure containing signature. 243 * \param cert Certificate containing key to verify signature. 244 * \param hash Hash of the plain data on which signature has to be verified. 245 * \param hashlen Length of the hash. 246 * 247 * \note This function is different from mbedtls_pkcs7_signed_data_verify() 248 * in a way that it directly receives the hash of the data. 249 * 250 * \return 0 if the signature verifies, or a negative error code on failure. 251 */ 252 int mbedtls_pkcs7_signed_hash_verify( mbedtls_pkcs7 *pkcs7, 253 const mbedtls_x509_crt *cert, 254 const unsigned char *hash, size_t hashlen); 255 256 /** 257 * \brief Unallocate all PKCS7 data and zeroize the memory. 258 * It doesn't free pkcs7 itself. It should be done by the caller. 259 * 260 * \param pkcs7 PKCS7 structure to free. 261 */ 262 void mbedtls_pkcs7_free( mbedtls_pkcs7 *pkcs7 ); 263 264 #ifdef __cplusplus 265 } 266 #endif 267 268 #endif /* pkcs7.h */ 269
