/** * \file pkcs7.h * * \brief PKCS #7 generic defines and structures * https://tools.ietf.org/html/rfc2315 */ /* * Copyright The Mbed TLS Contributors * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later */ /** * Note: For the time being, this implementation of the PKCS #7 cryptographic * message syntax is a partial implementation of RFC 2315. * Differences include: * - The RFC specifies 6 different content types. The only type currently * supported in Mbed TLS is the signed-data content type. * - The only supported PKCS #7 Signed Data syntax version is version 1 * - The RFC specifies support for BER. This implementation is limited to * DER only. * - The RFC specifies that multiple digest algorithms can be specified * in the Signed Data type. Only one digest algorithm is supported in Mbed TLS. * - The RFC specifies the Signed Data type can contain multiple X.509 or PKCS #6 extended * certificates. In Mbed TLS, this list can only contain 0 or 1 certificates * and they must be in X.509 format. * - The RFC specifies the Signed Data type can contain * certificate-revocation lists (CRLs). This implementation has no support * for CRLs so it is assumed to be an empty list. * - The RFC allows for SignerInfo structure to optionally contain * unauthenticatedAttributes and authenticatedAttributes. In Mbed TLS it is * assumed these fields are empty. * - The RFC allows for the signed Data type to contain contentInfo. This * implementation assumes the type is DATA and the content is empty. */ #ifndef MBEDTLS_PKCS7_H #define MBEDTLS_PKCS7_H #include "mbedtls/private_access.h" #include "mbedtls/build_info.h" #include "mbedtls/asn1.h" #include "mbedtls/x509.h" #include "mbedtls/x509_crt.h" /** * \name PKCS #7 Module Error codes * \{ */ #define MBEDTLS_ERR_PKCS7_INVALID_FORMAT -0x5300 /**< The format is invalid, e.g. different type expected. */ #define MBEDTLS_ERR_PKCS7_FEATURE_UNAVAILABLE -0x5380 /**< Unavailable feature, e.g. anything other than signed data. */ #define MBEDTLS_ERR_PKCS7_INVALID_VERSION -0x5400 /**< The PKCS #7 version element is invalid or cannot be parsed. */ #define MBEDTLS_ERR_PKCS7_INVALID_CONTENT_INFO -0x5480 /**< The PKCS #7 content info is invalid or cannot be parsed. */ #define MBEDTLS_ERR_PKCS7_INVALID_ALG -0x5500 /**< The algorithm tag or value is invalid or cannot be parsed. */ #define MBEDTLS_ERR_PKCS7_INVALID_CERT -0x5580 /**< The certificate tag or value is invalid or cannot be parsed. */ #define MBEDTLS_ERR_PKCS7_INVALID_SIGNATURE -0x5600 /**< Error parsing the signature */ #define MBEDTLS_ERR_PKCS7_INVALID_SIGNER_INFO -0x5680 /**< Error parsing the signer's info */ #define MBEDTLS_ERR_PKCS7_BAD_INPUT_DATA -0x5700 /**< Input invalid. */ #define MBEDTLS_ERR_PKCS7_ALLOC_FAILED -0x5780 /**< Allocation of memory failed. */ #define MBEDTLS_ERR_PKCS7_VERIFY_FAIL -0x5800 /**< Verification Failed */ #define MBEDTLS_ERR_PKCS7_CERT_DATE_INVALID -0x5880 /**< The PKCS #7 date issued/expired dates are invalid */ /* \} name */ /** * \name PKCS #7 Supported Version * \{ */ #define MBEDTLS_PKCS7_SUPPORTED_VERSION 0x01 /* \} name */ #ifdef __cplusplus extern "C" { #endif /** * Type-length-value structure that allows for ASN.1 using DER. */ typedef mbedtls_asn1_buf mbedtls_pkcs7_buf; /** * Container for ASN.1 named information objects. * It allows for Relative Distinguished Names (e.g. cn=localhost,ou=code,etc.). */ typedef mbedtls_asn1_named_data mbedtls_pkcs7_name; /** * Container for a sequence of ASN.1 items */ typedef mbedtls_asn1_sequence mbedtls_pkcs7_sequence; /** * PKCS #7 types */ typedef enum { MBEDTLS_PKCS7_NONE=0, MBEDTLS_PKCS7_DATA, MBEDTLS_PKCS7_SIGNED_DATA, MBEDTLS_PKCS7_ENVELOPED_DATA, MBEDTLS_PKCS7_SIGNED_AND_ENVELOPED_DATA, MBEDTLS_PKCS7_DIGESTED_DATA, MBEDTLS_PKCS7_ENCRYPTED_DATA, } mbedtls_pkcs7_type; /** * Structure holding PKCS #7 signer info */ typedef struct mbedtls_pkcs7_signer_info { int MBEDTLS_PRIVATE(version); mbedtls_x509_buf MBEDTLS_PRIVATE(serial); mbedtls_x509_name MBEDTLS_PRIVATE(issuer); mbedtls_x509_buf MBEDTLS_PRIVATE(issuer_raw); mbedtls_x509_buf MBEDTLS_PRIVATE(alg_identifier); mbedtls_x509_buf MBEDTLS_PRIVATE(sig_alg_identifier); mbedtls_x509_buf MBEDTLS_PRIVATE(sig); struct mbedtls_pkcs7_signer_info *MBEDTLS_PRIVATE(next); } mbedtls_pkcs7_signer_info; /** * Structure holding the signed data section */ typedef struct mbedtls_pkcs7_signed_data { int MBEDTLS_PRIVATE(version); mbedtls_pkcs7_buf MBEDTLS_PRIVATE(digest_alg_identifiers); int MBEDTLS_PRIVATE(no_of_certs); mbedtls_x509_crt MBEDTLS_PRIVATE(certs); int MBEDTLS_PRIVATE(no_of_crls); mbedtls_x509_crl MBEDTLS_PRIVATE(crl); int MBEDTLS_PRIVATE(no_of_signers); mbedtls_pkcs7_signer_info MBEDTLS_PRIVATE(signers); } mbedtls_pkcs7_signed_data; /** * Structure holding PKCS #7 structure, only signed data for now */ typedef struct mbedtls_pkcs7 { mbedtls_pkcs7_buf MBEDTLS_PRIVATE(raw); mbedtls_pkcs7_signed_data MBEDTLS_PRIVATE(signed_data); } mbedtls_pkcs7; /** * \brief Initialize mbedtls_pkcs7 structure. * * \param pkcs7 mbedtls_pkcs7 structure. */ void mbedtls_pkcs7_init(mbedtls_pkcs7 *pkcs7); /** * \brief Parse a single DER formatted PKCS #7 detached signature. * * \param pkcs7 The mbedtls_pkcs7 structure to be filled by the parser. * \param buf The buffer holding only the DER encoded PKCS #7 content. * \param buflen The size in bytes of \p buf. The size must be exactly the * length of the DER encoded PKCS #7 content. * * \note This function makes an internal copy of the PKCS #7 buffer * \p buf. In particular, \p buf may be destroyed or reused * after this call returns. * \note Signatures with internal data are not supported. * * \return The \c mbedtls_pkcs7_type of \p buf, if successful. * \return A negative error code on failure. */ int mbedtls_pkcs7_parse_der(mbedtls_pkcs7 *pkcs7, const unsigned char *buf, const size_t buflen); /** * \brief Verification of PKCS #7 signature against a caller-supplied * certificate. * * For each signer in the PKCS structure, this function computes * a signature over the supplied data, using the supplied * certificate and the same digest algorithm as specified by the * signer. It then compares this signature against the * signer's signature; verification succeeds if any comparison * matches. * * This function does not use the certificates held within the * PKCS #7 structure itself, and does not check that the * certificate is signed by a trusted certification authority. * * \param pkcs7 mbedtls_pkcs7 structure containing signature. * \param cert Certificate containing key to verify signature. * \param data Plain data on which signature has to be verified. * \param datalen Length of the data. * * \note This function internally calculates the hash on the supplied * plain data for signature verification. * * \return 0 if the signature verifies, or a negative error code on failure. */ int mbedtls_pkcs7_signed_data_verify(mbedtls_pkcs7 *pkcs7, const mbedtls_x509_crt *cert, const unsigned char *data, size_t datalen); /** * \brief Verification of PKCS #7 signature against a caller-supplied * certificate. * * For each signer in the PKCS structure, this function * validates a signature over the supplied hash, using the * supplied certificate and the same digest algorithm as * specified by the signer. Verification succeeds if any * signature is good. * * This function does not use the certificates held within the * PKCS #7 structure itself, and does not check that the * certificate is signed by a trusted certification authority. * * \param pkcs7 PKCS #7 structure containing signature. * \param cert Certificate containing key to verify signature. * \param hash Hash of the plain data on which signature has to be verified. * \param hashlen Length of the hash. * * \note This function is different from mbedtls_pkcs7_signed_data_verify() * in that it is directly passed the hash of the data. * * \return 0 if the signature verifies, or a negative error code on failure. */ int mbedtls_pkcs7_signed_hash_verify(mbedtls_pkcs7 *pkcs7, const mbedtls_x509_crt *cert, const unsigned char *hash, size_t hashlen); /** * \brief Unallocate all PKCS #7 data and zeroize the memory. * It doesn't free \p pkcs7 itself. This should be done by the caller. * * \param pkcs7 mbedtls_pkcs7 structure to free. */ void mbedtls_pkcs7_free(mbedtls_pkcs7 *pkcs7); #ifdef __cplusplus } #endif #endif /* pkcs7.h */