[Skiboot] [PATCH v6 17/20] crypto: add out-of-tree mbedtls pkcs7 parser
Eric Richter
erichte at linux.ibm.com
Thu Sep 17 02:21:28 AEST 2020
From: Nayna Jain <nayna at linux.ibm.com>
This patch adds a pkcs7 parser for mbedtls that hasn't yet
gone upstream. Once/if that implementation is accepted,
this patch can be removed.
Signed-off-by: Nayna Jain <nayna at linux.ibm.com>
Signed-off-by: Eric Richter <erichte at linux.ibm.com>
---
V6:
- allow parsing bare SignedData blobs
- mbedtls_pkcs7_parse_der now returns the data type instead of 0 on
success
- adjusted for feedback based on ongoing pull request
- now errors if it detects multiple signers (only single is supported
for now)
libstb/crypto/Makefile.inc | 4 +-
libstb/crypto/mbedtls-config.h | 1 +
libstb/crypto/mbedtls/include/mbedtls/oid.h | 11 +
libstb/crypto/pkcs7/Makefile.inc | 12 +
libstb/crypto/pkcs7/pkcs7.c | 596 ++++++++++++++++++++
libstb/crypto/pkcs7/pkcs7.h | 225 ++++++++
6 files changed, 848 insertions(+), 1 deletion(-)
create mode 100644 libstb/crypto/pkcs7/Makefile.inc
create mode 100644 libstb/crypto/pkcs7/pkcs7.c
create mode 100644 libstb/crypto/pkcs7/pkcs7.h
diff --git a/libstb/crypto/Makefile.inc b/libstb/crypto/Makefile.inc
index 42b5d8b9..ed2387e3 100644
--- a/libstb/crypto/Makefile.inc
+++ b/libstb/crypto/Makefile.inc
@@ -42,6 +42,8 @@ MBEDTLS_SRCS = $(addprefix mbedtls/library/,$(MBED_CRYPTO_SRCS) $(MBED_X509_SRCS
MBEDTLS_OBJS = $(MBEDTLS_SRCS:%.c=%.o)
+include $(CRYPTO_DIR)/pkcs7/Makefile.inc
+
CRYPTO = $(CRYPTO_DIR)/built-in.a
-$(CRYPTO): $(MBEDTLS_OBJS:%=$(CRYPTO_DIR)/%)
+$(CRYPTO): $(MBEDTLS_OBJS:%=$(CRYPTO_DIR)/%) $(PKCS7)
diff --git a/libstb/crypto/mbedtls-config.h b/libstb/crypto/mbedtls-config.h
index 414bbfd8..9560993b 100644
--- a/libstb/crypto/mbedtls-config.h
+++ b/libstb/crypto/mbedtls-config.h
@@ -72,6 +72,7 @@
//#define MBEDTLS_PEM_PARSE_C
#define MBEDTLS_PK_C
#define MBEDTLS_PK_PARSE_C
+#define MBEDTLS_PKCS7_C
//#define MBEDTLS_PK_WRITE_C
#define MBEDTLS_PLATFORM_C
#define MBEDTLS_RSA_C
diff --git a/libstb/crypto/mbedtls/include/mbedtls/oid.h b/libstb/crypto/mbedtls/include/mbedtls/oid.h
index 6fbd018a..a879d7df 100644
--- a/libstb/crypto/mbedtls/include/mbedtls/oid.h
+++ b/libstb/crypto/mbedtls/include/mbedtls/oid.h
@@ -190,6 +190,7 @@
#define MBEDTLS_OID_PKCS MBEDTLS_OID_RSA_COMPANY "\x01" /**< pkcs OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840) rsadsi(113549) 1 } */
#define MBEDTLS_OID_PKCS1 MBEDTLS_OID_PKCS "\x01" /**< pkcs-1 OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) 1 } */
#define MBEDTLS_OID_PKCS5 MBEDTLS_OID_PKCS "\x05" /**< pkcs-5 OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) 5 } */
+#define MBEDTLS_OID_PKCS7 MBEDTLS_OID_PKCS "\x07" /**< pkcs-7 OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) 7 } */
#define MBEDTLS_OID_PKCS9 MBEDTLS_OID_PKCS "\x09" /**< pkcs-9 OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) 9 } */
#define MBEDTLS_OID_PKCS12 MBEDTLS_OID_PKCS "\x0c" /**< pkcs-12 OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) 12 } */
@@ -274,6 +275,16 @@
#define MBEDTLS_OID_PKCS5_PBE_SHA1_DES_CBC MBEDTLS_OID_PKCS5 "\x0a" /**< pbeWithSHA1AndDES-CBC OBJECT IDENTIFIER ::= {pkcs-5 10} */
#define MBEDTLS_OID_PKCS5_PBE_SHA1_RC2_CBC MBEDTLS_OID_PKCS5 "\x0b" /**< pbeWithSHA1AndRC2-CBC OBJECT IDENTIFIER ::= {pkcs-5 11} */
+/*
+ * PKCS#7 OIDs
+ */
+#define MBEDTLS_OID_PKCS7_DATA MBEDTLS_OID_PKCS7 "\x01" /**< Content type is Data OBJECT IDENTIFIER ::= {pkcs-7 1} */
+#define MBEDTLS_OID_PKCS7_SIGNED_DATA MBEDTLS_OID_PKCS7 "\x02" /**< Content type is Signed Data OBJECT IDENTIFIER ::= {pkcs-7 1} */
+#define MBEDTLS_OID_PKCS7_ENVELOPED_DATA MBEDTLS_OID_PKCS7 "\x03" /**< Content type is Enveloped Data OBJECT IDENTIFIER ::= {pkcs-7 1} */
+#define MBEDTLS_OID_PKCS7_SIGNED_AND_ENVELOPED_DATA MBEDTLS_OID_PKCS7 "\x04" /**< Content type is Signed and Enveloped Data OBJECT IDENTIFIER ::= {pkcs-7 1} */
+#define MBEDTLS_OID_PKCS7_DIGESTED_DATA MBEDTLS_OID_PKCS7 "\x05" /**< Content type is Digested Data OBJECT IDENTIFIER ::= {pkcs-7 1} */
+#define MBEDTLS_OID_PKCS7_ENCRYPTED_DATA MBEDTLS_OID_PKCS7 "\x06" /**< Content type is Encrypted Data OBJECT IDENTIFIER ::= {pkcs-7 1} */
+
/*
* PKCS#8 OIDs
*/
diff --git a/libstb/crypto/pkcs7/Makefile.inc b/libstb/crypto/pkcs7/Makefile.inc
new file mode 100644
index 00000000..bef339b5
--- /dev/null
+++ b/libstb/crypto/pkcs7/Makefile.inc
@@ -0,0 +1,12 @@
+
+PKCS7_DIR = libstb/crypto/pkcs7
+
+SUBDIRS += $(PKCS7_DIR)
+
+PKCS7_SRCS = pkcs7.c
+PKCS7_OBJS = $(PKCS7_SRCS:%.c=%.o)
+PKCS7 = $(PKCS7_DIR)/built-in.a
+
+CFLAGS_$(PKCS7_DIR)/ = -I$(SRC)/$(LIBSTB_DIR)/crypto -DMBEDTLS_CONFIG_FILE='<mbedtls-config.h>'
+
+$(PKCS7): $(PKCS7_OBJS:%=$(PKCS7_DIR)/%)
diff --git a/libstb/crypto/pkcs7/pkcs7.c b/libstb/crypto/pkcs7/pkcs7.c
new file mode 100644
index 00000000..4407e201
--- /dev/null
+++ b/libstb/crypto/pkcs7/pkcs7.c
@@ -0,0 +1,596 @@
+/* Copyright 2019 IBM Corp.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+ * implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#if !defined(MBEDTLS_CONFIG_FILE)
+#include "mbedtls/config.h"
+#else
+#include MBEDTLS_CONFIG_FILE
+#endif
+#if defined(MBEDTLS_PKCS7_C)
+
+#include "mbedtls/x509.h"
+#include "mbedtls/asn1.h"
+#include "pkcs7.h"
+#include "mbedtls/x509_crt.h"
+#include "mbedtls/x509_crl.h"
+#include "mbedtls/oid.h"
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#if defined(MBEDTLS_FS_IO)
+#include <sys/types.h>
+#include <sys/stat.h>
+#endif
+#include <unistd.h>
+
+#if defined(MBEDTLS_PLATFORM_C)
+#include "mbedtls/platform.h"
+#include "mbedtls/platform_util.h"
+#else
+#include <stdio.h>
+#include <stdlib.h>
+#define mbedtls_free free
+#define mbedtls_calloc calloc
+#define mbedtls_printf printf
+#define mbedtls_snprintf snprintf
+#endif
+
+#if defined(MBEDTLS_HAVE_TIME)
+#include "mbedtls/platform_time.h"
+#endif
+#if defined(MBEDTLS_HAVE_TIME_DATE)
+#include <time.h>
+#endif
+
+#if defined(MBEDTLS_FS_IO)
+/*
+ * Load all data from a file into a given buffer.
+ *
+ * The file is expected to contain DER encoded data.
+ * A terminating null byte is always appended.
+ */
+int mbedtls_pkcs7_load_file( const char *path, unsigned char **buf, size_t *n )
+{
+ FILE *file;
+
+ if( ( file = fopen( path, "rb" ) ) == NULL )
+ return( MBEDTLS_ERR_PKCS7_FILE_IO_ERROR );
+
+ fseek( file, 0, SEEK_END );
+ *n = (size_t) ftell( file );
+ fseek( file, 0, SEEK_SET );
+
+ *buf = mbedtls_calloc( 1, *n + 1 );
+ if( *buf == NULL )
+ return( MBEDTLS_ERR_PKCS7_ALLOC_FAILED );
+
+ if( fread( *buf, 1, *n, file ) != *n )
+ {
+ fclose( file );
+
+ mbedtls_platform_zeroize( *buf, *n + 1 );
+ mbedtls_free( *buf );
+
+ return( MBEDTLS_ERR_PKCS7_FILE_IO_ERROR );
+ }
+
+ fclose( file );
+
+ (*buf)[*n] = '\0';
+
+ return( 0 );
+}
+#endif
+
+/**
+ * Initializes the pkcs7 structure.
+ */
+void mbedtls_pkcs7_init( mbedtls_pkcs7 *pkcs7 )
+{
+ memset( pkcs7, 0, sizeof( mbedtls_pkcs7 ) );
+}
+
+static int pkcs7_get_next_content_len( unsigned char **p, unsigned char *end,
+ size_t *len )
+{
+ int ret;
+
+ if( ( ret = mbedtls_asn1_get_tag( p, end, len, MBEDTLS_ASN1_CONSTRUCTED
+ | MBEDTLS_ASN1_CONTEXT_SPECIFIC ) ) != 0 )
+ {
+ return( MBEDTLS_ERR_PKCS7_INVALID_FORMAT + ret );
+ }
+
+ return( 0 );
+}
+
+/**
+ * version Version
+ * Version ::= INTEGER
+ **/
+static int pkcs7_get_version( unsigned char **p, unsigned char *end, int *ver )
+{
+ int ret;
+
+ if( ( ret = mbedtls_asn1_get_int( p, end, ver ) ) != 0 )
+ return( MBEDTLS_ERR_PKCS7_INVALID_FORMAT + ret );
+
+ /* If version != 1, return invalid version */
+ if( *ver != MBEDTLS_PKCS7_SUPPORTED_VERSION )
+ return( MBEDTLS_ERR_PKCS7_INVALID_VERSION );
+
+ return( 0 );
+}
+
+/**
+ * ContentInfo ::= SEQUENCE {
+ * contentType ContentType,
+ * content
+ * [0] EXPLICIT ANY DEFINED BY contentType OPTIONAL }
+ **/
+static int pkcs7_get_content_info_type( unsigned char **p, unsigned char *end,
+ mbedtls_pkcs7_buf *pkcs7 )
+{
+ size_t len = 0;
+ int ret;
+ unsigned char *start = *p;
+
+ ret = mbedtls_asn1_get_tag( p, end, &len, MBEDTLS_ASN1_CONSTRUCTED
+ | MBEDTLS_ASN1_SEQUENCE );
+ if( ret != 0 )
+ return( MBEDTLS_ERR_PKCS7_INVALID_CONTENT_INFO + ret );
+
+ ret = mbedtls_asn1_get_tag( p, end, &len, MBEDTLS_ASN1_OID );
+ if( ret != 0 ) {
+ *p = start;
+ return( MBEDTLS_ERR_PKCS7_INVALID_CONTENT_INFO + ret );
+ }
+
+ pkcs7->tag = MBEDTLS_ASN1_OID;
+ pkcs7->len = len;
+ pkcs7->p = *p;
+
+ return( ret );
+}
+
+/**
+ * DigestAlgorithmIdentifier ::= AlgorithmIdentifier
+ *
+ * This is from x509.h
+ **/
+static int pkcs7_get_digest_algorithm( unsigned char **p, unsigned char *end,
+ mbedtls_x509_buf *alg )
+{
+ int ret;
+
+ if( ( ret = mbedtls_asn1_get_alg_null( p, end, alg ) ) != 0 )
+ return( MBEDTLS_ERR_PKCS7_INVALID_ALG + ret );
+
+ return( 0 );
+}
+
+/**
+ * DigestAlgorithmIdentifiers :: SET of DigestAlgorithmIdentifier
+ **/
+static int pkcs7_get_digest_algorithm_set( unsigned char **p,
+ unsigned char *end,
+ mbedtls_x509_buf *alg )
+{
+ size_t len = 0;
+ int ret;
+
+ ret = mbedtls_asn1_get_tag( p, end, &len, MBEDTLS_ASN1_CONSTRUCTED
+ | MBEDTLS_ASN1_SET );
+ if( ret != 0 )
+ return( MBEDTLS_ERR_PKCS7_INVALID_ALG + ret );
+
+ end = *p + len;
+
+ /** For now, it assumes there is only one digest algorithm specified **/
+ ret = mbedtls_asn1_get_alg_null( p, end, alg );
+ if( ret != 0 )
+ return( MBEDTLS_ERR_PKCS7_INVALID_ALG + ret );
+
+ if (*p != end)
+ return ( MBEDTLS_ERR_PKCS7_INVALID_FORMAT );
+
+ return( 0 );
+}
+
+/**
+ * certificates :: SET OF ExtendedCertificateOrCertificate,
+ * ExtendedCertificateOrCertificate ::= CHOICE {
+ * certificate Certificate -- x509,
+ * extendedCertificate[0] IMPLICIT ExtendedCertificate }
+ **/
+static int pkcs7_get_certificates( unsigned char **p, unsigned char *end,
+ mbedtls_x509_crt *certs )
+{
+ int ret;
+ size_t len1 = 0;
+ size_t len2 = 0;
+ unsigned char *end_set, *end_cert;
+ unsigned char *start = *p;
+
+ if( ( ret = mbedtls_asn1_get_tag( p, end, &len1, MBEDTLS_ASN1_CONSTRUCTED
+ | MBEDTLS_ASN1_CONTEXT_SPECIFIC ) ) != 0 )
+ {
+ if( ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
+ return( 0 );
+
+ return( MBEDTLS_ERR_PKCS7_INVALID_FORMAT + ret );
+ }
+ start = *p;
+ end_set = *p + len1;
+
+ /* This is to verify that there is only signer certificate, it can
+ have its chain though. */
+ ret = mbedtls_asn1_get_tag( p, end_set, &len2, MBEDTLS_ASN1_CONSTRUCTED
+ | MBEDTLS_ASN1_SEQUENCE );
+ if( ret != 0 )
+ return( MBEDTLS_ERR_PKCS7_INVALID_FORMAT + ret );
+
+ end_cert = *p + len2;
+
+ if (end_cert != end_set)
+ return (MBEDTLS_ERR_PKCS7_INVALID_FORMAT);
+
+ /* Since it satisfies the condition of single signer, continue parsing */
+ *p = start;
+ if( ( ret = mbedtls_x509_crt_parse( certs, *p, len1 ) ) < 0 )
+ return( ret );
+
+ *p = *p + len1;
+
+ /**
+ * Currently we do not check for certificate chain, so we are not handling
+ * "> 0" case. Return if atleast one certificate in the chain is correctly
+ * parsed.
+ **/
+
+ return( 0 );
+}
+
+/**
+ * EncryptedDigest ::= OCTET STRING
+ **/
+static int pkcs7_get_signature( unsigned char **p, unsigned char *end,
+ mbedtls_pkcs7_buf *signature )
+{
+ int ret;
+ size_t len = 0;
+
+ ret = mbedtls_asn1_get_tag( p, end, &len, MBEDTLS_ASN1_OCTET_STRING );
+ if( ret != 0 )
+ return( MBEDTLS_ERR_PKCS7_INVALID_SIGNATURE + ret );
+
+ signature->tag = MBEDTLS_ASN1_OCTET_STRING;
+ signature->len = len;
+ signature->p = *p;
+
+ *p = *p + len;
+
+ return( 0 );
+}
+
+/**
+ * SignerInfos ::= SET of SignerInfo
+ * SignerInfo ::= SEQUENCE {
+ * version Version;
+ * issuerAndSerialNumber IssuerAndSerialNumber,
+ * digestAlgorithm DigestAlgorithmIdentifier,
+ * authenticatedAttributes
+ * [0] IMPLICIT Attributes OPTIONAL,
+ * digestEncryptionAlgorithm DigestEncryptionAlgorithmIdentifier,
+ * encryptedDigest EncryptedDigest,
+ * unauthenticatedAttributes
+ * [1] IMPLICIT Attributes OPTIONAL,
+ **/
+static int pkcs7_get_signers_info_set( unsigned char **p, unsigned char *end,
+ mbedtls_pkcs7_signer_info *signers_set )
+{
+ unsigned char *end_set;
+ int ret;
+ size_t len = 0;
+
+ ret = mbedtls_asn1_get_tag( p, end, &len, MBEDTLS_ASN1_CONSTRUCTED
+ | MBEDTLS_ASN1_SET );
+ if( ret != 0 )
+ return( MBEDTLS_ERR_PKCS7_INVALID_SIGNER_INFO + ret );
+
+ end_set = *p + len;
+
+ ret = mbedtls_asn1_get_tag( p, end_set, &len, MBEDTLS_ASN1_CONSTRUCTED
+ | MBEDTLS_ASN1_SEQUENCE );
+ if( ret != 0 )
+ return( MBEDTLS_ERR_PKCS7_INVALID_SIGNER_INFO + ret );
+
+ end_set = *p + len;
+
+ ret = mbedtls_asn1_get_int( p, end_set, &signers_set->version );
+ if( ret != 0 )
+ return( MBEDTLS_ERR_PKCS7_INVALID_SIGNER_INFO + ret );
+
+ ret = mbedtls_asn1_get_tag( p, end_set, &len, MBEDTLS_ASN1_CONSTRUCTED
+ | MBEDTLS_ASN1_SEQUENCE );
+ if( ret != 0 )
+ return( MBEDTLS_ERR_PKCS7_INVALID_SIGNER_INFO + ret );
+
+ /* Parsing IssuerAndSerialNumber */
+ signers_set->issuer_raw.p = *p;
+
+ ret = mbedtls_asn1_get_tag( p, end_set, &len, MBEDTLS_ASN1_CONSTRUCTED
+ | MBEDTLS_ASN1_SEQUENCE );
+ if( ret != 0 )
+ return( MBEDTLS_ERR_PKCS7_INVALID_SIGNER_INFO + ret );
+
+ ret = mbedtls_x509_get_name( p, *p + len, &signers_set->issuer );
+ if( ret != 0 )
+ return( ret );
+
+ signers_set->issuer_raw.len = *p - signers_set->issuer_raw.p;
+
+ ret = mbedtls_x509_get_serial( p, end_set, &signers_set->serial );
+ if( ret != 0 )
+ return( ret );
+
+ ret = pkcs7_get_digest_algorithm( p, end_set,
+ &signers_set->alg_identifier );
+ if( ret != 0 )
+ return( ret );
+
+ ret = pkcs7_get_digest_algorithm( p, end_set,
+ &signers_set->sig_alg_identifier );
+ if( ret != 0 )
+ return( ret );
+
+ ret = pkcs7_get_signature( p, end_set, &signers_set->sig );
+ if( ret != 0 )
+ return( ret );
+
+ signers_set->next = NULL;
+
+ if (*p != end_set)
+ return ( MBEDTLS_ERR_PKCS7_INVALID_SIGNER_INFO );
+
+ return( 0 );
+}
+
+/**
+ * SignedData ::= SEQUENCE {
+ * version Version,
+ * digestAlgorithms DigestAlgorithmIdentifiers,
+ * contentInfo ContentInfo,
+ * certificates
+ * [0] IMPLICIT ExtendedCertificatesAndCertificates
+ * OPTIONAL,
+ * crls
+ * [0] IMPLICIT CertificateRevocationLists OPTIONAL,
+ * signerInfos SignerInfos }
+ */
+static int pkcs7_get_signed_data( unsigned char *buf, size_t buflen,
+ mbedtls_pkcs7_signed_data *signed_data )
+{
+ unsigned char *p = buf;
+ unsigned char *end = buf + buflen;
+ unsigned char *end_set;
+ size_t len = 0;
+ int ret;
+ mbedtls_md_type_t md_alg;
+
+ ret = mbedtls_asn1_get_tag( &p, end, &len, MBEDTLS_ASN1_CONSTRUCTED
+ | MBEDTLS_ASN1_SEQUENCE );
+ if( ret != 0 )
+ return( MBEDTLS_ERR_PKCS7_INVALID_FORMAT + ret );
+
+ end_set = p + len;
+
+ /* Get version of signed data */
+ ret = pkcs7_get_version( &p, end_set, &signed_data->version );
+ if( ret != 0 )
+ return( ret );
+
+ /* Get digest algorithm */
+ ret = pkcs7_get_digest_algorithm_set( &p, end_set,
+ &signed_data->digest_alg_identifiers );
+ if( ret != 0 )
+ return( ret );
+
+ ret = mbedtls_oid_get_md_alg( &signed_data->digest_alg_identifiers, &md_alg );
+ if( ret != 0 )
+ return( MBEDTLS_ERR_PKCS7_INVALID_ALG + ret );
+
+ /* Do not expect any content */
+ ret = pkcs7_get_content_info_type( &p, end_set, &signed_data->content.oid );
+ if( ret != 0 )
+ return( ret );
+
+ if( MBEDTLS_OID_CMP( MBEDTLS_OID_PKCS7_DATA, &signed_data->content.oid ) )
+ {
+ return( MBEDTLS_ERR_PKCS7_INVALID_CONTENT_INFO ) ;
+ }
+
+ p = p + signed_data->content.oid.len;
+
+ /* Look for certificates, there may or may not be any */
+ mbedtls_x509_crt_init( &signed_data->certs );
+ ret = pkcs7_get_certificates( &p, end_set, &signed_data->certs );
+ if( ret != 0 )
+ return( ret ) ;
+
+ /* TODO: optional CRLs go here, currently no CRLs are expected */
+
+ /* Get signers info */
+ ret = pkcs7_get_signers_info_set( &p, end_set, &signed_data->signers );
+ if( ret != 0 )
+ return( ret );
+
+ if ( p != end )
+ ret = MBEDTLS_ERR_PKCS7_INVALID_FORMAT;
+
+ return( ret );
+}
+
+int mbedtls_pkcs7_parse_der( const unsigned char *buf, const int buflen,
+ mbedtls_pkcs7 *pkcs7 )
+{
+ unsigned char *start;
+ unsigned char *end;
+ size_t len = 0;
+ int ret;
+ int isoidset = 0;
+
+ /* use internal buffer for parsing */
+ start = (unsigned char *)buf;
+ end = start + buflen;
+
+ if( !pkcs7 )
+ return( MBEDTLS_ERR_PKCS7_BAD_INPUT_DATA );
+
+ ret = pkcs7_get_content_info_type( &start, end, &pkcs7->content_type_oid );
+ if( ret != 0 )
+ {
+ len = buflen;
+ goto try_data;
+ }
+
+ if( ! MBEDTLS_OID_CMP( MBEDTLS_OID_PKCS7_DATA, &pkcs7->content_type_oid )
+ || ! MBEDTLS_OID_CMP( MBEDTLS_OID_PKCS7_ENCRYPTED_DATA, &pkcs7->content_type_oid )
+ || ! MBEDTLS_OID_CMP( MBEDTLS_OID_PKCS7_ENVELOPED_DATA, &pkcs7->content_type_oid )
+ || ! MBEDTLS_OID_CMP( MBEDTLS_OID_PKCS7_SIGNED_AND_ENVELOPED_DATA, &pkcs7->content_type_oid )
+ || ! MBEDTLS_OID_CMP( MBEDTLS_OID_PKCS7_DIGESTED_DATA, &pkcs7->content_type_oid )
+ || ! MBEDTLS_OID_CMP( MBEDTLS_OID_PKCS7_ENCRYPTED_DATA, &pkcs7->content_type_oid ) )
+ {
+ ret = MBEDTLS_ERR_PKCS7_FEATURE_UNAVAILABLE;
+ goto out;
+ }
+
+ if( MBEDTLS_OID_CMP( MBEDTLS_OID_PKCS7_SIGNED_DATA, &pkcs7->content_type_oid ) )
+ {
+ ret = MBEDTLS_ERR_PKCS7_BAD_INPUT_DATA;
+ goto out;
+ }
+
+ isoidset = 1;
+ start = start + pkcs7->content_type_oid.len;
+
+ ret = pkcs7_get_next_content_len( &start, end, &len );
+ if( ret != 0 )
+ goto out;
+
+try_data:
+ ret = pkcs7_get_signed_data( start, len, &pkcs7->signed_data );
+ if (ret != 0)
+ goto out;
+
+ if (!isoidset)
+ {
+ pkcs7->content_type_oid.tag = MBEDTLS_ASN1_OID;
+ pkcs7->content_type_oid.len = MBEDTLS_OID_SIZE(MBEDTLS_OID_PKCS7_SIGNED_DATA);
+ pkcs7->content_type_oid.p = (unsigned char *)MBEDTLS_OID_PKCS7_SIGNED_DATA;
+ }
+
+ ret = MBEDTLS_PKCS7_SIGNED_DATA;
+
+out:
+ if ( ret < 0 )
+ mbedtls_pkcs7_free( pkcs7 );
+
+ return( ret );
+}
+
+int mbedtls_pkcs7_signed_data_verify( mbedtls_pkcs7 *pkcs7,
+ mbedtls_x509_crt *cert,
+ const unsigned char *data,
+ size_t datalen )
+{
+
+ int ret;
+ unsigned char *hash;
+ mbedtls_pk_context pk_cxt = cert->pk;
+ const mbedtls_md_info_t *md_info;
+ mbedtls_md_type_t md_alg;
+
+ ret = mbedtls_oid_get_md_alg( &pkcs7->signed_data.digest_alg_identifiers, &md_alg );
+ if( ret != 0 )
+ return( MBEDTLS_ERR_PKCS7_INVALID_ALG + ret );
+
+ md_info = mbedtls_md_info_from_type( md_alg );
+
+ hash = mbedtls_calloc( mbedtls_md_get_size( md_info ), 1 );
+ if( hash == NULL ) {
+ return( MBEDTLS_ERR_PKCS7_ALLOC_FAILED );
+ }
+
+ mbedtls_md( md_info, data, datalen, hash );
+
+ ret = mbedtls_pk_verify( &pk_cxt, md_alg, hash, sizeof(hash),
+ pkcs7->signed_data.signers.sig.p,
+ pkcs7->signed_data.signers.sig.len );
+
+ mbedtls_free( hash );
+
+ return( ret );
+}
+
+int mbedtls_pkcs7_signed_hash_verify( mbedtls_pkcs7 *pkcs7,
+ mbedtls_x509_crt *cert,
+ const unsigned char *hash, int hashlen)
+{
+ int ret;
+ mbedtls_md_type_t md_alg;
+ mbedtls_pk_context pk_cxt;
+
+ ret = mbedtls_oid_get_md_alg( &pkcs7->signed_data.digest_alg_identifiers, &md_alg );
+ if( ret != 0 )
+ return( MBEDTLS_ERR_PKCS7_INVALID_ALG + ret );
+
+ pk_cxt = cert->pk;
+ ret = mbedtls_pk_verify( &pk_cxt, md_alg, hash, hashlen,
+ pkcs7->signed_data.signers.sig.p,
+ pkcs7->signed_data.signers.sig.len );
+
+ return ( ret );
+}
+
+/*
+ * Unallocate all pkcs7 data
+ */
+void mbedtls_pkcs7_free( mbedtls_pkcs7 *pkcs7 )
+{
+ mbedtls_x509_name *name_cur;
+ mbedtls_x509_name *name_prv;
+
+ if( pkcs7 == NULL )
+ return;
+
+ mbedtls_x509_crt_free( &pkcs7->signed_data.certs );
+ mbedtls_x509_crl_free( &pkcs7->signed_data.crl );
+
+ name_cur = pkcs7->signed_data.signers.issuer.next;
+ while( name_cur != NULL )
+ {
+ name_prv = name_cur;
+ name_cur = name_cur->next;
+ mbedtls_platform_zeroize( name_prv, sizeof( mbedtls_x509_name ) );
+ mbedtls_free( name_prv );
+ }
+
+ mbedtls_platform_zeroize( pkcs7, sizeof( mbedtls_pkcs7 ) );
+}
+
+#endif
diff --git a/libstb/crypto/pkcs7/pkcs7.h b/libstb/crypto/pkcs7/pkcs7.h
new file mode 100644
index 00000000..df898a61
--- /dev/null
+++ b/libstb/crypto/pkcs7/pkcs7.h
@@ -0,0 +1,225 @@
+/**
+ * \file pkcs7.h
+ *
+ * \brief PKCS7 generic defines and structures
+ */
+/*
+ * Copyright (C) 2019, IBM Corp, All Rights Reserved
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * This file is part of mbed TLS (https://tls.mbed.org)
+ */
+#ifndef MBEDTLS_PKCS7_H
+#define MBEDTLS_PKCS7_H
+
+#if !defined(MBEDTLS_CONFIG_FILE)
+#include "config.h"
+#else
+#include MBEDTLS_CONFIG_FILE
+#endif
+
+#include "mbedtls/asn1.h"
+#include "mbedtls/x509.h"
+#include "mbedtls/x509_crt.h"
+
+/**
+ * \name PKCS7 Error codes
+ * \{
+ */
+#define MBEDTLS_ERR_PKCS7_FEATURE_UNAVAILABLE -0x5300 /**< Unavailable feature, e.g. anything other than signed data. */
+#define MBEDTLS_ERR_PKCS7_INVALID_FORMAT -0x53F0 /**< The CRT/CRL format is invalid, e.g. different type expected. */
+#define MBEDTLS_ERR_PKCS7_INVALID_VERSION -0x5400 /**< The PKCS7 version element is invalid or cannot be parsed. */
+#define MBEDTLS_ERR_PKCS7_INVALID_CONTENT_INFO -0x54F0 /**< The PKCS7 content info 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_SIGNATURE -0x55F0 /**< Error parsing the signature */
+#define MBEDTLS_ERR_PKCS7_INVALID_SIGNER_INFO -0x5600 /**< Error parsing the signer's info */
+#define MBEDTLS_ERR_PKCS7_BAD_INPUT_DATA -0x56F0 /**< Input invalid. */
+#define MBEDTLS_ERR_PKCS7_ALLOC_FAILED -0x5700 /**< Allocation of memory failed. */
+#define MBEDTLS_ERR_PKCS7_FILE_IO_ERROR -0x57F0 /**< File Read/Write Error */
+/* \} name */
+
+/**
+ * \name PKCS7 Supported Version
+ * \{
+ */
+#define MBEDTLS_PKCS7_SUPPORTED_VERSION 0x01
+/* \} name */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * Type-length-value structure that allows for ASN1 using DER.
+ */
+typedef mbedtls_asn1_buf mbedtls_pkcs7_buf;
+
+/**
+ * Container for ASN1 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;
+
+/**
+ * PKCS7 types
+ */
+typedef enum {
+ MBEDTLS_PKCS7_NONE=0,
+ MBEDTLS_PKCS7_DATA,
+ MBEDTLS_PKCS7_SIGNED_DATA,
+ MBEDTLS_PKCS7_ENVELOPED_DATA,
+ MBEDTLS_PKCS7_SIGNED_AND_ENVELOPED_DAYA,
+ MBEDTLS_PKCS7_DIGESTED_DATA,
+ MBEDTLS_PKCS7_ENCRYPTED_DATA,
+}
+mbedtls_pkcs7_type;
+
+/**
+ * Structure holding PKCS7 signer info
+ */
+typedef struct mbedtls_pkcs7_signer_info
+{
+ int version;
+ mbedtls_x509_buf serial;
+ mbedtls_x509_name issuer;
+ mbedtls_x509_buf issuer_raw;
+ mbedtls_x509_buf alg_identifier;
+ mbedtls_x509_buf sig_alg_identifier;
+ mbedtls_x509_buf sig;
+ struct mbedtls_pkcs7_signer_info *next;
+}
+mbedtls_pkcs7_signer_info;
+
+/**
+ * Structure holding attached data as part of PKCS7 signed data format
+ */
+typedef struct mbedtls_pkcs7_data
+{
+ mbedtls_pkcs7_buf oid;
+ mbedtls_pkcs7_buf data;
+}
+mbedtls_pkcs7_data;
+
+/**
+ * Structure holding the signed data section
+ */
+typedef struct mbedtls_pkcs7_signed_data
+{
+ int version;
+ mbedtls_pkcs7_buf digest_alg_identifiers;
+ struct mbedtls_pkcs7_data content;
+ mbedtls_x509_crt certs;
+ mbedtls_x509_crl crl;
+ struct mbedtls_pkcs7_signer_info signers;
+}
+mbedtls_pkcs7_signed_data;
+
+/**
+ * Structure holding PKCS7 structure, only signed data for now
+ */
+typedef struct mbedtls_pkcs7
+{
+ mbedtls_pkcs7_buf content_type_oid;
+ struct mbedtls_pkcs7_signed_data signed_data;
+}
+mbedtls_pkcs7;
+
+/**
+ * \brief Initialize pkcs7 structure.
+ *
+ * \param pkcs7 pkcs7 structure.
+ */
+void mbedtls_pkcs7_init( mbedtls_pkcs7 *pkcs7 );
+
+/**
+ * \brief Parse a single DER formatted pkcs7 content.
+ *
+ * \param buf The buffer holding the DER encoded pkcs7.
+ * \param buflen The size in Bytes of \p buf.
+ *
+ * \note This function makes an internal copy of the PKCS7 buffer
+ * \p buf. In particular, \p buf may be destroyed or reused
+ * after this call returns.
+ *
+ * \return \c 0, if successful.
+ * \return A negative error code on failure.
+ */
+int mbedtls_pkcs7_parse_der( const unsigned char *buf, const int buflen,
+ mbedtls_pkcs7 *pkcs7 );
+
+/**
+ * \brief Verification of PKCS7 signature.
+ *
+ * \param pkcs7 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 A negative error code on failure.
+ */
+int mbedtls_pkcs7_signed_data_verify( mbedtls_pkcs7 *pkcs7,
+ mbedtls_x509_crt *cert,
+ const unsigned char *data,
+ size_t datalen );
+
+/**
+ * \brief Verification of PKCS7 signature.
+ *
+ * \param pkcs7 PKCS7 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 a way that it directly recieves the hash of the data.
+ *
+ * \return A negative error code on failure.
+ */
+int mbedtls_pkcs7_signed_hash_verify( mbedtls_pkcs7 *pkcs7,
+ mbedtls_x509_crt *cert,
+ const unsigned char *hash, int hashlen);
+
+/**
+ * \brief Reads the PKCS7 data from the file in a buffer.
+ *
+ * \param path Path of the file.
+ * \param buf Buffer to store the PKCS7 contents from the file.
+ * \param n Size of the buffer (the contents read from the file).
+ *
+ * \return A negative error code on failure.
+ */
+int mbedtls_pkcs7_load_file( const char *path, unsigned char **buf, size_t *n );
+
+/**
+ * \brief Unallocate all PKCS7 data and zeroize the memory.
+ * It doesn't free pkcs7 itself. It should be done by the caller.
+ *
+ * \param pkcs7 PKCS7 structure to free.
+ */
+void mbedtls_pkcs7_free( mbedtls_pkcs7 *pkcs7 );
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* pkcs7.h */
--
2.21.1
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