Merge pull request #7252 from daverodgman/enable_pkcs7

Enable PKCS 7

ChangeLog.d/pkcs7-parser.txt

@@ -0,0 +1,15 @@
+Features
+   * Added partial support for parsing the PKCS #7 Cryptographic Message
+     Syntax, as defined in RFC 2315. Currently, support is limited to the
+     following:
+     - Only the signed-data content type, version 1 is supported.
+     - Only DER encoding is supported.
+     - Only a single digest algorithm per message is supported.
+     - Certificates must be in X.509 format. A message must have either 0
+       or 1 certificates.
+     - There is no support for certificate revocation lists.
+     - The authenticated and unauthenticated attribute fields of SignerInfo
+       must be empty.
+     Many thanks to Daniel Axtens, Nayna Jain, and Nick Child from IBM for
+     contributing this feature, and to Demi-Marie Obenour for contributing
+     various improvements, tests and bug fixes.

include/mbedtls/mbedtls_config.h

@@ -2862,11 +2862,7 @@
 /**
  * \def MBEDTLS_PKCS7_C
  *
- * This feature is a work in progress and not ready for production. Testing and
+ * Enable PKCS #7 core for using PKCS #7-formatted signatures.
- * validation is incomplete, and handling of malformed inputs may not be robust.
- * The API may change.
- *
- * Enable PKCS7 core for using PKCS7 formatted signatures.
  * RFC Link - https://tools.ietf.org/html/rfc2315
  *
  * Module:  library/pkcs7.c
@@ -2875,9 +2871,9 @@
  *           MBEDTLS_X509_CRT_PARSE_C MBEDTLS_X509_CRL_PARSE_C,
  *           MBEDTLS_BIGNUM_C, MBEDTLS_MD_C
  *
- * This module is required for the PKCS7 parsing modules.
+ * This module is required for the PKCS #7 parsing modules.
  */
-//#define MBEDTLS_PKCS7_C
+#define MBEDTLS_PKCS7_C
 
 /**
  * \def MBEDTLS_PKCS12_C

include/mbedtls/pkcs7.h

@@ -1,7 +1,7 @@
 /**
  * \file pkcs7.h
  *
- * \brief PKCS7 generic defines and structures
+ * \brief PKCS #7 generic defines and structures
  *  https://tools.ietf.org/html/rfc2315
  */
 /*
@@ -22,27 +22,22 @@
  */
 
 /**
- * This feature is a work in progress and not ready for production. The API may
+ * Note: For the time being, this implementation of the PKCS #7 cryptographic
- * change. Furthermore, please note that the implementation has only been
- * validated with well-formed inputs, not yet with untrusted inputs (which is
- * almost always the case in practice).
- *
- * Note: For the time being, this implementation of the PKCS7 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.
+ *    supported in Mbed TLS is the signed-data content type.
- *  - The only supported PKCS7 Signed Data syntax version is version 1
+ *  - 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 X509 or PKCS6
+ *  - 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 X509 format.
+ *    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
+ *    certificate-revocation lists (CRLs). This implementation has no support
- *    for crls so it is assumed to be an empty list.
+ *    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.
@@ -62,13 +57,13 @@
 #include "mbedtls/x509_crt.h"
 
 /**
- * \name PKCS7 Module Error codes
+ * \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 PKCS7 version element is invalid or cannot be parsed. */
+#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 PKCS7 content info 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 */
@@ -76,11 +71,11 @@
 #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 PKCS7 date issued/expired dates are invalid */
+#define MBEDTLS_ERR_PKCS7_CERT_DATE_INVALID                -0x5880  /**< The PKCS #7 date issued/expired dates are invalid */
 /* \} name */
 
 /**
- * \name PKCS7 Supported Version
+ * \name PKCS #7 Supported Version
  * \{
  */
 #define MBEDTLS_PKCS7_SUPPORTED_VERSION                           0x01
@@ -91,12 +86,12 @@ extern "C" {
 #endif
 
 /**
- * Type-length-value structure that allows for ASN1 using DER.
+ * Type-length-value structure that allows for ASN.1 using DER.
  */
 typedef mbedtls_asn1_buf mbedtls_pkcs7_buf;
 
 /**
- * Container for ASN1 named information objects.
+ * 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;
@@ -107,7 +102,7 @@ typedef mbedtls_asn1_named_data mbedtls_pkcs7_name;
 typedef mbedtls_asn1_sequence mbedtls_pkcs7_sequence;
 
 /**
- * PKCS7 types
+ * PKCS #7 types
  */
 typedef enum {
     MBEDTLS_PKCS7_NONE=0,
@@ -121,7 +116,7 @@ typedef enum {
 mbedtls_pkcs7_type;
 
 /**
- * Structure holding PKCS7 signer info
+ * Structure holding PKCS #7 signer info
  */
 typedef struct mbedtls_pkcs7_signer_info {
     int MBEDTLS_PRIVATE(version);
@@ -151,7 +146,7 @@ typedef struct mbedtls_pkcs7_signed_data {
 mbedtls_pkcs7_signed_data;
 
 /**
- * Structure holding PKCS7 structure, only signed data for now
+ * Structure holding PKCS #7 structure, only signed data for now
  */
 typedef struct mbedtls_pkcs7 {
     mbedtls_pkcs7_buf MBEDTLS_PRIVATE(raw);
@@ -160,21 +155,21 @@ typedef struct mbedtls_pkcs7 {
 mbedtls_pkcs7;
 
 /**
- * \brief          Initialize pkcs7 structure.
+ * \brief          Initialize mbedtls_pkcs7 structure.
  *
- * \param pkcs7    pkcs7 structure.
+ * \param pkcs7    mbedtls_pkcs7 structure.
  */
 void mbedtls_pkcs7_init(mbedtls_pkcs7 *pkcs7);
 
 /**
- * \brief          Parse a single DER formatted pkcs7 detached signature.
+ * \brief          Parse a single DER formatted PKCS #7 detached signature.
  *
- * \param pkcs7    The pkcs7 structure to be filled by parser for the output.
+ * \param pkcs7    The mbedtls_pkcs7 structure to be filled by the parser.
- * \param buf      The buffer holding only the DER encoded pkcs7.
+ * \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 pkcs7.
+ *                 length of the DER encoded PKCS #7 content.
  *
- * \note           This function makes an internal copy of the PKCS7 buffer
+ * \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.
@@ -186,7 +181,7 @@ int mbedtls_pkcs7_parse_der(mbedtls_pkcs7 *pkcs7, const unsigned char *buf,
                             const size_t buflen);
 
 /**
- * \brief          Verification of PKCS7 signature against a caller-supplied
+ * \brief          Verification of PKCS #7 signature against a caller-supplied
  *                 certificate.
  *
  *                 For each signer in the PKCS structure, this function computes
@@ -197,10 +192,10 @@ int mbedtls_pkcs7_parse_der(mbedtls_pkcs7 *pkcs7, const unsigned char *buf,
  *                 matches.
  *
  *                 This function does not use the certificates held within the
- *                 PKCS7 structure itself, and does not check that the
+ *                 PKCS #7 structure itself, and does not check that the
  *                 certificate is signed by a trusted certification authority.
  *
- * \param pkcs7    PKCS7 structure containing signature.
+ * \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.
@@ -216,7 +211,7 @@ int mbedtls_pkcs7_signed_data_verify(mbedtls_pkcs7 *pkcs7,
                                      size_t datalen);
 
 /**
- * \brief          Verification of PKCS7 signature against a caller-supplied
+ * \brief          Verification of PKCS #7 signature against a caller-supplied
  *                 certificate.
  *
  *                 For each signer in the PKCS structure, this function
@@ -226,10 +221,10 @@ int mbedtls_pkcs7_signed_data_verify(mbedtls_pkcs7 *pkcs7,
  *                 signature is good.
  *
  *                 This function does not use the certificates held within the
- *                 PKCS7 structure itself, and does not check that the
+ *                 PKCS #7 structure itself, and does not check that the
  *                 certificate is signed by a trusted certification authority.
  *
- * \param pkcs7    PKCS7 structure containing signature.
+ * \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.
@@ -244,10 +239,10 @@ int mbedtls_pkcs7_signed_hash_verify(mbedtls_pkcs7 *pkcs7,
                                      const unsigned char *hash, size_t hashlen);
 
 /**
- * \brief          Unallocate all PKCS7 data and zeroize the memory.
+ * \brief          Unallocate all PKCS #7 data and zeroize the memory.
- *                 It doesn't free pkcs7 itself. It should be done by the caller.
+ *                 It doesn't free \p pkcs7 itself. This should be done by the caller.
  *
- * \param pkcs7    PKCS7 structure to free.
+ * \param pkcs7    mbedtls_pkcs7 structure to free.
  */
 void mbedtls_pkcs7_free(mbedtls_pkcs7 *pkcs7);
 

library/pkcs7.c

@@ -42,7 +42,7 @@
 #endif
 
 /**
- * Initializes the pkcs7 structure.
+ * Initializes the mbedtls_pkcs7 structure.
  */
 void mbedtls_pkcs7_init(mbedtls_pkcs7 *pkcs7)
 {

tests/suites/test_suite_pkcs7.data

@@ -23,13 +23,17 @@ depends_on:MBEDTLS_SHA256_C:MBEDTLS_RSA_C
 pkcs7_parse:"data_files/pkcs7_data_signed_badcert.der":MBEDTLS_ERR_PKCS7_INVALID_CERT
 
 PKCS7 Signed Data Parse Fail with disabled alg #5.1
-depends_on:MBEDTLS_RSA_C:!MBEDTLS_SHA512_C
+depends_on:MBEDTLS_RSA_C:!MBEDTLS_HAS_ALG_SHA_512_VIA_LOWLEVEL_OR_PSA
 pkcs7_parse:"data_files/pkcs7_data_cert_signed_sha512.der":MBEDTLS_ERR_PKCS7_INVALID_ALG
 
 PKCS7 Parse Fail with Inlined Content Info #5.2
 depends_on:MBEDTLS_SHA256_C:MBEDTLS_RSA_C
 pkcs7_parse:"data_files/pkcs7_data_with_signature.der":MBEDTLS_ERR_PKCS7_FEATURE_UNAVAILABLE
 
+PKCS7 Signed Data Parse Fail with no RSA #5.3
+depends_on:MBEDTLS_SHA256_C:!MBEDTLS_RSA_C
+pkcs7_parse:"data_files/pkcs7_data_cert_signed_sha256.der":MBEDTLS_ERR_PKCS7_INVALID_CERT
+
 PKCS7 Signed Data Parse Fail with corrupted signer info #6
 depends_on:MBEDTLS_SHA256_C:MBEDTLS_RSA_C
 pkcs7_parse:"data_files/pkcs7_data_signed_badsigner.der":MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS7_INVALID_SIGNER_INFO,MBEDTLS_ERR_ASN1_UNEXPECTED_TAG)
@@ -71,7 +75,7 @@ depends_on:MBEDTLS_SHA1_C:MBEDTLS_SHA256_C
 pkcs7_verify:"data_files/pkcs7_zerolendata_detached.der":"data_files/pkcs7-rsa-sha256-1.der":"data_files/pkcs7_zerolendata.bin":0:0
 
 PKCS7 Signed Data Verification Fail zero-len data
-depends_on:MBEDTLS_SHA1_C:MBEDTLS_SHA256_C
+depends_on:MBEDTLS_SHA1_C:MBEDTLS_SHA256_C:MBEDTLS_RSA_C
 pkcs7_verify:"data_files/pkcs7_zerolendata_detached.der":"data_files/pkcs7-rsa-sha256-2.der":"data_files/pkcs7_zerolendata.bin":0:MBEDTLS_ERR_RSA_VERIFY_FAILED
 
 PKCS7 Signed Data Verification Pass SHA256 #9
@@ -91,19 +95,19 @@ depends_on:MBEDTLS_SHA512_C:MBEDTLS_SHA256_C
 pkcs7_verify:"data_files/pkcs7_data_cert_signed_sha512.der":"data_files/pkcs7-rsa-sha256-1.der":"data_files/pkcs7_data.bin":0:0
 
 PKCS7 Signed Data Verification Fail because of different certificate #12
-depends_on:MBEDTLS_SHA256_C
+depends_on:MBEDTLS_SHA256_C:MBEDTLS_RSA_C
 pkcs7_verify:"data_files/pkcs7_data_cert_signed_sha256.der":"data_files/pkcs7-rsa-sha256-2.der":"data_files/pkcs7_data.bin":0:MBEDTLS_ERR_RSA_VERIFY_FAILED
 
 PKCS7 Signed Data Verification Fail because of different data hash #13
-depends_on:MBEDTLS_SHA256_C
+depends_on:MBEDTLS_SHA256_C:MBEDTLS_RSA_C
 pkcs7_verify:"data_files/pkcs7_data_cert_signed_sha256.der":"data_files/pkcs7-rsa-sha256-1.der":"data_files/pkcs7_data_1.bin":0:MBEDTLS_ERR_RSA_VERIFY_FAILED
 
 PKCS7 Signed Data Parse Failure Corrupt signerInfo.issuer #15.1
-depends_on:MBEDTLS_SHA256_C
+depends_on:MBEDTLS_SHA256_C:MBEDTLS_RSA_C
 pkcs7_parse:"data_files/pkcs7_signerInfo_issuer_invalid_size.der":MBEDTLS_ERR_PKCS7_INVALID_SIGNER_INFO
 
 PKCS7 Signed Data Parse Failure Corrupt signerInfo.serial #15.2
-depends_on:MBEDTLS_SHA256_C
+depends_on:MBEDTLS_SHA256_C:MBEDTLS_RSA_C
 pkcs7_parse:"data_files/pkcs7_signerInfo_serial_invalid_size.der":MBEDTLS_ERR_PKCS7_INVALID_SIGNER_INFO
 
 PKCS7 Signed Data Parse Fail Corrupt signerInfos[2] (6213931373035520)
@@ -123,7 +127,7 @@ depends_on:MBEDTLS_SHA256_C
 pkcs7_verify:"data_files/pkcs7_data_multiple_signed.der":"data_files/pkcs7-rsa-sha256-1.crt data_files/pkcs7-rsa-sha256-2.crt":"data_files/pkcs7_data.bin":0:0
 
 PKCS7 Signed Data Verify with multiple(3) signers #16.1
-depends_on:MBEDTLS_SHA256_C
+depends_on:MBEDTLS_SHA256_C:!MBEDTLS_MEMORY_BUFFER_ALLOC_C
 pkcs7_verify:"data_files/pkcs7_data_3_signed.der":"data_files/pkcs7-rsa-sha256-1.crt data_files/pkcs7-rsa-sha256-2.crt data_files/pkcs7-rsa-sha256-3.crt":"data_files/pkcs7_data.bin":0:0
 
 PKCS7 Signed Data Hash Verify with multiple signers #17
@@ -143,11 +147,11 @@ depends_on:MBEDTLS_SHA256_C:MBEDTLS_HAVE_TIME_DATE
 pkcs7_verify:"data_files/pkcs7_data_cert_signed_sha256.der":"data_files/pkcs7-rsa-expired.crt":"data_files/pkcs7_data.bin":0:MBEDTLS_ERR_PKCS7_CERT_DATE_INVALID
 
 PKCS7 Signed Data Verify Fail Expired Cert #19 no DATE_TIME 1
-depends_on:MBEDTLS_SHA256_C:!MBEDTLS_HAVE_TIME_DATE
+depends_on:MBEDTLS_SHA256_C:!MBEDTLS_HAVE_TIME_DATE:MBEDTLS_RSA_C
 pkcs7_verify:"data_files/pkcs7_data_cert_signed_sha256.der":"data_files/pkcs7-rsa-expired.crt":"data_files/pkcs7_data.bin":0:MBEDTLS_ERR_RSA_VERIFY_FAILED
 
 PKCS7 Signed Data Verify Fail Expired Cert #19 no TIME_DATE 2
-depends_on:MBEDTLS_SHA256_C:!MBEDTLS_HAVE_TIME_DATE
+depends_on:MBEDTLS_SHA256_C:!MBEDTLS_HAVE_TIME_DATE:MBEDTLS_RSA_C
 pkcs7_verify:"data_files/pkcs7_data_rsa_expired.der":"data_files/pkcs7-rsa-expired.crt":"data_files/pkcs7_data_1.bin":0:MBEDTLS_ERR_RSA_VERIFY_FAILED
 
 PKCS7 Parse Failure Invalid ASN1: Add null byte to start #20.0

tests/suites/test_suite_pkcs7.function

@@ -7,10 +7,11 @@
 #include "mbedtls/oid.h"
 #include "sys/types.h"
 #include "sys/stat.h"
+#include "mbedtls/rsa.h"
 /* END_HEADER */
 
 /* BEGIN_DEPENDENCIES
- * depends_on:MBEDTLS_PKCS7_C:MBEDTLS_RSA_C
+ * depends_on:MBEDTLS_PKCS7_C
  * END_DEPENDENCIES
  */
 /* BEGIN_SUITE_HELPERS */