--- /dev/null
+/*
+ * X.509 certificate parsing and verification
+ *
+ * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
+ * SPDX-License-Identifier: GPL-2.0
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * This file is part of mbed TLS (https://tls.mbed.org)
+ */
+/*
+ * The ITU-T X.509 standard defines a certificate format for PKI.
+ *
+ * http://www.ietf.org/rfc/rfc5280.txt (Certificates and CRLs)
+ * http://www.ietf.org/rfc/rfc3279.txt (Alg IDs for CRLs)
+ * http://www.ietf.org/rfc/rfc2986.txt (CSRs, aka PKCS#10)
+ *
+ * http://www.itu.int/ITU-T/studygroups/com17/languages/X.680-0207.pdf
+ * http://www.itu.int/ITU-T/studygroups/com17/languages/X.690-0207.pdf
+ *
+ * [SIRO] https://cabforum.org/wp-content/uploads/Chunghwatelecom201503cabforumV4.pdf
+ */
+
+#if !defined(MBEDTLS_CONFIG_FILE)
+#include "mbedtls/config.h"
+#else
+#include MBEDTLS_CONFIG_FILE
+#endif
+
+#if defined(MBEDTLS_X509_CRT_PARSE_C)
+
+#include "mbedtls/x509_crt.h"
+#include "mbedtls/oid.h"
+#include "mbedtls/platform_util.h"
+
+#include <stdio.h>
+#include <string.h>
+
+#if defined(MBEDTLS_PEM_PARSE_C)
+#include "mbedtls/pem.h"
+#endif
+
+#if defined(MBEDTLS_PLATFORM_C)
+#include "mbedtls/platform.h"
+#else
+#include <stdlib.h>
+#define mbedtls_free free
+#define mbedtls_calloc calloc
+#define mbedtls_snprintf snprintf
+#endif
+
+#if defined(MBEDTLS_THREADING_C)
+#include "mbedtls/threading.h"
+#endif
+
+#if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32)
+#include <windows.h>
+#else
+#include <time.h>
+#endif
+
+#if defined(MBEDTLS_FS_IO)
+#include <stdio.h>
+#if !defined(_WIN32) || defined(EFIX64) || defined(EFI32)
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <dirent.h>
+#endif /* !_WIN32 || EFIX64 || EFI32 */
+#endif
+
+/*
+ * Item in a verification chain: cert and flags for it
+ */
+typedef struct {
+ mbedtls_x509_crt *crt;
+ uint32_t flags;
+} x509_crt_verify_chain_item;
+
+/*
+ * Max size of verification chain: end-entity + intermediates + trusted root
+ */
+#define X509_MAX_VERIFY_CHAIN_SIZE ( MBEDTLS_X509_MAX_INTERMEDIATE_CA + 2 )
+
+/*
+ * Default profile
+ */
+const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_default =
+{
+#if defined(MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_CERTIFICATES)
+ /* Allow SHA-1 (weak, but still safe in controlled environments) */
+ MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA1 ) |
+#endif
+ /* Only SHA-2 hashes */
+ MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA224 ) |
+ MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA256 ) |
+ MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA384 ) |
+ MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA512 ),
+ 0xFFFFFFF, /* Any PK alg */
+ 0xFFFFFFF, /* Any curve */
+ 2048,
+};
+
+/*
+ * Next-default profile
+ */
+const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_next =
+{
+ /* Hashes from SHA-256 and above */
+ MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA256 ) |
+ MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA384 ) |
+ MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA512 ),
+ 0xFFFFFFF, /* Any PK alg */
+#if defined(MBEDTLS_ECP_C)
+ /* Curves at or above 128-bit security level */
+ MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP256R1 ) |
+ MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP384R1 ) |
+ MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP521R1 ) |
+ MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_BP256R1 ) |
+ MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_BP384R1 ) |
+ MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_BP512R1 ) |
+ MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP256K1 ),
+#else
+ 0,
+#endif
+ 2048,
+};
+
+/*
+ * NSA Suite B Profile
+ */
+const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_suiteb =
+{
+ /* Only SHA-256 and 384 */
+ MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA256 ) |
+ MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA384 ),
+ /* Only ECDSA */
+ MBEDTLS_X509_ID_FLAG( MBEDTLS_PK_ECDSA ) |
+ MBEDTLS_X509_ID_FLAG( MBEDTLS_PK_ECKEY ),
+#if defined(MBEDTLS_ECP_C)
+ /* Only NIST P-256 and P-384 */
+ MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP256R1 ) |
+ MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP384R1 ),
+#else
+ 0,
+#endif
+ 0,
+};
+
+/*
+ * Check md_alg against profile
+ * Return 0 if md_alg is acceptable for this profile, -1 otherwise
+ */
+static int x509_profile_check_md_alg( const mbedtls_x509_crt_profile *profile,
+ mbedtls_md_type_t md_alg )
+{
+ if( md_alg == MBEDTLS_MD_NONE )
+ return( -1 );
+
+ if( ( profile->allowed_mds & MBEDTLS_X509_ID_FLAG( md_alg ) ) != 0 )
+ return( 0 );
+
+ return( -1 );
+}
+
+/*
+ * Check pk_alg against profile
+ * Return 0 if pk_alg is acceptable for this profile, -1 otherwise
+ */
+static int x509_profile_check_pk_alg( const mbedtls_x509_crt_profile *profile,
+ mbedtls_pk_type_t pk_alg )
+{
+ if( pk_alg == MBEDTLS_PK_NONE )
+ return( -1 );
+
+ if( ( profile->allowed_pks & MBEDTLS_X509_ID_FLAG( pk_alg ) ) != 0 )
+ return( 0 );
+
+ return( -1 );
+}
+
+/*
+ * Check key against profile
+ * Return 0 if pk is acceptable for this profile, -1 otherwise
+ */
+static int x509_profile_check_key( const mbedtls_x509_crt_profile *profile,
+ const mbedtls_pk_context *pk )
+{
+ const mbedtls_pk_type_t pk_alg = mbedtls_pk_get_type( pk );
+
+#if defined(MBEDTLS_RSA_C)
+ if( pk_alg == MBEDTLS_PK_RSA || pk_alg == MBEDTLS_PK_RSASSA_PSS )
+ {
+ if( mbedtls_pk_get_bitlen( pk ) >= profile->rsa_min_bitlen )
+ return( 0 );
+
+ return( -1 );
+ }
+#endif
+
+#if defined(MBEDTLS_ECP_C)
+ if( pk_alg == MBEDTLS_PK_ECDSA ||
+ pk_alg == MBEDTLS_PK_ECKEY ||
+ pk_alg == MBEDTLS_PK_ECKEY_DH )
+ {
+ const mbedtls_ecp_group_id gid = mbedtls_pk_ec( *pk )->grp.id;
+
+ if( gid == MBEDTLS_ECP_DP_NONE )
+ return( -1 );
+
+ if( ( profile->allowed_curves & MBEDTLS_X509_ID_FLAG( gid ) ) != 0 )
+ return( 0 );
+
+ return( -1 );
+ }
+#endif
+
+ return( -1 );
+}
+
+/*
+ * Version ::= INTEGER { v1(0), v2(1), v3(2) }
+ */
+static int x509_get_version( unsigned char **p,
+ const unsigned char *end,
+ int *ver )
+{
+ int ret;
+ size_t len;
+
+ if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
+ MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | 0 ) ) != 0 )
+ {
+ if( ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
+ {
+ *ver = 0;
+ return( 0 );
+ }
+
+ return( ret );
+ }
+
+ end = *p + len;
+
+ if( ( ret = mbedtls_asn1_get_int( p, end, ver ) ) != 0 )
+ return( MBEDTLS_ERR_X509_INVALID_VERSION + ret );
+
+ if( *p != end )
+ return( MBEDTLS_ERR_X509_INVALID_VERSION +
+ MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
+
+ return( 0 );
+}
+
+/*
+ * Validity ::= SEQUENCE {
+ * notBefore Time,
+ * notAfter Time }
+ */
+static int x509_get_dates( unsigned char **p,
+ const unsigned char *end,
+ mbedtls_x509_time *from,
+ mbedtls_x509_time *to )
+{
+ int ret;
+ size_t len;
+
+ if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
+ MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
+ return( MBEDTLS_ERR_X509_INVALID_DATE + ret );
+
+ end = *p + len;
+
+ if( ( ret = mbedtls_x509_get_time( p, end, from ) ) != 0 )
+ return( ret );
+
+ if( ( ret = mbedtls_x509_get_time( p, end, to ) ) != 0 )
+ return( ret );
+
+ if( *p != end )
+ return( MBEDTLS_ERR_X509_INVALID_DATE +
+ MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
+
+ return( 0 );
+}
+
+/*
+ * X.509 v2/v3 unique identifier (not parsed)
+ */
+static int x509_get_uid( unsigned char **p,
+ const unsigned char *end,
+ mbedtls_x509_buf *uid, int n )
+{
+ int ret;
+
+ if( *p == end )
+ return( 0 );
+
+ uid->tag = **p;
+
+ if( ( ret = mbedtls_asn1_get_tag( p, end, &uid->len,
+ MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | n ) ) != 0 )
+ {
+ if( ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
+ return( 0 );
+
+ return( ret );
+ }
+
+ uid->p = *p;
+ *p += uid->len;
+
+ return( 0 );
+}
+
+static int x509_get_basic_constraints( unsigned char **p,
+ const unsigned char *end,
+ int *ca_istrue,
+ int *max_pathlen )
+{
+ int ret;
+ size_t len;
+
+ /*
+ * BasicConstraints ::= SEQUENCE {
+ * cA BOOLEAN DEFAULT FALSE,
+ * pathLenConstraint INTEGER (0..MAX) OPTIONAL }
+ */
+ *ca_istrue = 0; /* DEFAULT FALSE */
+ *max_pathlen = 0; /* endless */
+
+ if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
+ MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
+ return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
+
+ if( *p == end )
+ return( 0 );
+
+ if( ( ret = mbedtls_asn1_get_bool( p, end, ca_istrue ) ) != 0 )
+ {
+ if( ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
+ ret = mbedtls_asn1_get_int( p, end, ca_istrue );
+
+ if( ret != 0 )
+ return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
+
+ if( *ca_istrue != 0 )
+ *ca_istrue = 1;
+ }
+
+ if( *p == end )
+ return( 0 );
+
+ if( ( ret = mbedtls_asn1_get_int( p, end, max_pathlen ) ) != 0 )
+ return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
+
+ if( *p != end )
+ return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
+ MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
+
+ (*max_pathlen)++;
+
+ return( 0 );
+}
+
+static int x509_get_ns_cert_type( unsigned char **p,
+ const unsigned char *end,
+ unsigned char *ns_cert_type)
+{
+ int ret;
+ mbedtls_x509_bitstring bs = { 0, 0, NULL };
+
+ if( ( ret = mbedtls_asn1_get_bitstring( p, end, &bs ) ) != 0 )
+ return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
+
+ if( bs.len != 1 )
+ return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
+ MBEDTLS_ERR_ASN1_INVALID_LENGTH );
+
+ /* Get actual bitstring */
+ *ns_cert_type = *bs.p;
+ return( 0 );
+}
+
+static int x509_get_key_usage( unsigned char **p,
+ const unsigned char *end,
+ unsigned int *key_usage)
+{
+ int ret;
+ size_t i;
+ mbedtls_x509_bitstring bs = { 0, 0, NULL };
+
+ if( ( ret = mbedtls_asn1_get_bitstring( p, end, &bs ) ) != 0 )
+ return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
+
+ if( bs.len < 1 )
+ return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
+ MBEDTLS_ERR_ASN1_INVALID_LENGTH );
+
+ /* Get actual bitstring */
+ *key_usage = 0;
+ for( i = 0; i < bs.len && i < sizeof( unsigned int ); i++ )
+ {
+ *key_usage |= (unsigned int) bs.p[i] << (8*i);
+ }
+
+ return( 0 );
+}
+
+/*
+ * ExtKeyUsageSyntax ::= SEQUENCE SIZE (1..MAX) OF KeyPurposeId
+ *
+ * KeyPurposeId ::= OBJECT IDENTIFIER
+ */
+static int x509_get_ext_key_usage( unsigned char **p,
+ const unsigned char *end,
+ mbedtls_x509_sequence *ext_key_usage)
+{
+ int ret;
+
+ if( ( ret = mbedtls_asn1_get_sequence_of( p, end, ext_key_usage, MBEDTLS_ASN1_OID ) ) != 0 )
+ return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
+
+ /* Sequence length must be >= 1 */
+ if( ext_key_usage->buf.p == NULL )
+ return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
+ MBEDTLS_ERR_ASN1_INVALID_LENGTH );
+
+ return( 0 );
+}
+
+/*
+ * SubjectAltName ::= GeneralNames
+ *
+ * GeneralNames ::= SEQUENCE SIZE (1..MAX) OF GeneralName
+ *
+ * GeneralName ::= CHOICE {
+ * otherName [0] OtherName,
+ * rfc822Name [1] IA5String,
+ * dNSName [2] IA5String,
+ * x400Address [3] ORAddress,
+ * directoryName [4] Name,
+ * ediPartyName [5] EDIPartyName,
+ * uniformResourceIdentifier [6] IA5String,
+ * iPAddress [7] OCTET STRING,
+ * registeredID [8] OBJECT IDENTIFIER }
+ *
+ * OtherName ::= SEQUENCE {
+ * type-id OBJECT IDENTIFIER,
+ * value [0] EXPLICIT ANY DEFINED BY type-id }
+ *
+ * EDIPartyName ::= SEQUENCE {
+ * nameAssigner [0] DirectoryString OPTIONAL,
+ * partyName [1] DirectoryString }
+ *
+ * NOTE: we only parse and use dNSName at this point.
+ */
+static int x509_get_subject_alt_name( unsigned char **p,
+ const unsigned char *end,
+ mbedtls_x509_sequence *subject_alt_name )
+{
+ int ret;
+ size_t len, tag_len;
+ mbedtls_asn1_buf *buf;
+ unsigned char tag;
+ mbedtls_asn1_sequence *cur = subject_alt_name;
+
+ /* Get main sequence tag */
+ if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
+ MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
+ return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
+
+ if( *p + len != end )
+ return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
+ MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
+
+ while( *p < end )
+ {
+ if( ( end - *p ) < 1 )
+ return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
+ MBEDTLS_ERR_ASN1_OUT_OF_DATA );
+
+ tag = **p;
+ (*p)++;
+ if( ( ret = mbedtls_asn1_get_len( p, end, &tag_len ) ) != 0 )
+ return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
+
+ if( ( tag & MBEDTLS_ASN1_TAG_CLASS_MASK ) !=
+ MBEDTLS_ASN1_CONTEXT_SPECIFIC )
+ {
+ return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
+ MBEDTLS_ERR_ASN1_UNEXPECTED_TAG );
+ }
+
+ /* Skip everything but DNS name */
+ if( tag != ( MBEDTLS_ASN1_CONTEXT_SPECIFIC | 2 ) )
+ {
+ *p += tag_len;
+ continue;
+ }
+
+ /* Allocate and assign next pointer */
+ if( cur->buf.p != NULL )
+ {
+ if( cur->next != NULL )
+ return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS );
+
+ cur->next = mbedtls_calloc( 1, sizeof( mbedtls_asn1_sequence ) );
+
+ if( cur->next == NULL )
+ return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
+ MBEDTLS_ERR_ASN1_ALLOC_FAILED );
+
+ cur = cur->next;
+ }
+
+ buf = &(cur->buf);
+ buf->tag = tag;
+ buf->p = *p;
+ buf->len = tag_len;
+ *p += buf->len;
+ }
+
+ /* Set final sequence entry's next pointer to NULL */
+ cur->next = NULL;
+
+ if( *p != end )
+ return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
+ MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
+
+ return( 0 );
+}
+
+/*
+ * X.509 v3 extensions
+ *
+ */
+static int x509_get_crt_ext( unsigned char **p,
+ const unsigned char *end,
+ mbedtls_x509_crt *crt )
+{
+ int ret;
+ size_t len;
+ unsigned char *end_ext_data, *end_ext_octet;
+
+ if( ( ret = mbedtls_x509_get_ext( p, end, &crt->v3_ext, 3 ) ) != 0 )
+ {
+ if( ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
+ return( 0 );
+
+ return( ret );
+ }
+
+ while( *p < end )
+ {
+ /*
+ * Extension ::= SEQUENCE {
+ * extnID OBJECT IDENTIFIER,
+ * critical BOOLEAN DEFAULT FALSE,
+ * extnValue OCTET STRING }
+ */
+ mbedtls_x509_buf extn_oid = {0, 0, NULL};
+ int is_critical = 0; /* DEFAULT FALSE */
+ int ext_type = 0;
+
+ if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
+ MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
+ return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
+
+ end_ext_data = *p + len;
+
+ /* Get extension ID */
+ if( ( ret = mbedtls_asn1_get_tag( p, end_ext_data, &extn_oid.len,
+ MBEDTLS_ASN1_OID ) ) != 0 )
+ return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
+
+ extn_oid.tag = MBEDTLS_ASN1_OID;
+ extn_oid.p = *p;
+ *p += extn_oid.len;
+
+ /* Get optional critical */
+ if( ( ret = mbedtls_asn1_get_bool( p, end_ext_data, &is_critical ) ) != 0 &&
+ ( ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG ) )
+ return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
+
+ /* Data should be octet string type */
+ if( ( ret = mbedtls_asn1_get_tag( p, end_ext_data, &len,
+ MBEDTLS_ASN1_OCTET_STRING ) ) != 0 )
+ return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
+
+ end_ext_octet = *p + len;
+
+ if( end_ext_octet != end_ext_data )
+ return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
+ MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
+
+ /*
+ * Detect supported extensions
+ */
+ ret = mbedtls_oid_get_x509_ext_type( &extn_oid, &ext_type );
+
+ if( ret != 0 )
+ {
+ /* No parser found, skip extension */
+ *p = end_ext_octet;
+
+#if !defined(MBEDTLS_X509_ALLOW_UNSUPPORTED_CRITICAL_EXTENSION)
+ if( is_critical )
+ {
+ /* Data is marked as critical: fail */
+ return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
+ MBEDTLS_ERR_ASN1_UNEXPECTED_TAG );
+ }
+#endif
+ continue;
+ }
+
+ /* Forbid repeated extensions */
+ if( ( crt->ext_types & ext_type ) != 0 )
+ return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS );
+
+ crt->ext_types |= ext_type;
+
+ switch( ext_type )
+ {
+ case MBEDTLS_X509_EXT_BASIC_CONSTRAINTS:
+ /* Parse basic constraints */
+ if( ( ret = x509_get_basic_constraints( p, end_ext_octet,
+ &crt->ca_istrue, &crt->max_pathlen ) ) != 0 )
+ return( ret );
+ break;
+
+ case MBEDTLS_X509_EXT_KEY_USAGE:
+ /* Parse key usage */
+ if( ( ret = x509_get_key_usage( p, end_ext_octet,
+ &crt->key_usage ) ) != 0 )
+ return( ret );
+ break;
+
+ case MBEDTLS_X509_EXT_EXTENDED_KEY_USAGE:
+ /* Parse extended key usage */
+ if( ( ret = x509_get_ext_key_usage( p, end_ext_octet,
+ &crt->ext_key_usage ) ) != 0 )
+ return( ret );
+ break;
+
+ case MBEDTLS_X509_EXT_SUBJECT_ALT_NAME:
+ /* Parse subject alt name */
+ if( ( ret = x509_get_subject_alt_name( p, end_ext_octet,
+ &crt->subject_alt_names ) ) != 0 )
+ return( ret );
+ break;
+
+ case MBEDTLS_X509_EXT_NS_CERT_TYPE:
+ /* Parse netscape certificate type */
+ if( ( ret = x509_get_ns_cert_type( p, end_ext_octet,
+ &crt->ns_cert_type ) ) != 0 )
+ return( ret );
+ break;
+
+ default:
+ return( MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE );
+ }
+ }
+
+ if( *p != end )
+ return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
+ MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
+
+ return( 0 );
+}
+
+/*
+ * Parse and fill a single X.509 certificate in DER format
+ */
+static int x509_crt_parse_der_core( mbedtls_x509_crt *crt, const unsigned char *buf,
+ size_t buflen )
+{
+ int ret;
+ size_t len;
+ unsigned char *p, *end, *crt_end;
+ mbedtls_x509_buf sig_params1, sig_params2, sig_oid2;
+
+ memset( &sig_params1, 0, sizeof( mbedtls_x509_buf ) );
+ memset( &sig_params2, 0, sizeof( mbedtls_x509_buf ) );
+ memset( &sig_oid2, 0, sizeof( mbedtls_x509_buf ) );
+
+ /*
+ * Check for valid input
+ */
+ if( crt == NULL || buf == NULL )
+ return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
+
+ // Use the original buffer until we figure out actual length
+ p = (unsigned char*) buf;
+ len = buflen;
+ end = p + len;
+
+ /*
+ * Certificate ::= SEQUENCE {
+ * tbsCertificate TBSCertificate,
+ * signatureAlgorithm AlgorithmIdentifier,
+ * signatureValue BIT STRING }
+ */
+ if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
+ MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
+ {
+ mbedtls_x509_crt_free( crt );
+ return( MBEDTLS_ERR_X509_INVALID_FORMAT );
+ }
+
+ if( len > (size_t) ( end - p ) )
+ {
+ mbedtls_x509_crt_free( crt );
+ return( MBEDTLS_ERR_X509_INVALID_FORMAT +
+ MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
+ }
+ crt_end = p + len;
+
+ // Create and populate a new buffer for the raw field
+ crt->raw.len = crt_end - buf;
+ crt->raw.p = p = mbedtls_calloc( 1, crt->raw.len );
+ if( p == NULL )
+ return( MBEDTLS_ERR_X509_ALLOC_FAILED );
+
+ memcpy( p, buf, crt->raw.len );
+
+ // Direct pointers to the new buffer
+ p += crt->raw.len - len;
+ end = crt_end = p + len;
+
+ /*
+ * TBSCertificate ::= SEQUENCE {
+ */
+ crt->tbs.p = p;
+
+ if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
+ MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
+ {
+ mbedtls_x509_crt_free( crt );
+ return( MBEDTLS_ERR_X509_INVALID_FORMAT + ret );
+ }
+
+ end = p + len;
+ crt->tbs.len = end - crt->tbs.p;
+
+ /*
+ * Version ::= INTEGER { v1(0), v2(1), v3(2) }
+ *
+ * CertificateSerialNumber ::= INTEGER
+ *
+ * signature AlgorithmIdentifier
+ */
+ if( ( ret = x509_get_version( &p, end, &crt->version ) ) != 0 ||
+ ( ret = mbedtls_x509_get_serial( &p, end, &crt->serial ) ) != 0 ||
+ ( ret = mbedtls_x509_get_alg( &p, end, &crt->sig_oid,
+ &sig_params1 ) ) != 0 )
+ {
+ mbedtls_x509_crt_free( crt );
+ return( ret );
+ }
+
+ if( crt->version < 0 || crt->version > 2 )
+ {
+ mbedtls_x509_crt_free( crt );
+ return( MBEDTLS_ERR_X509_UNKNOWN_VERSION );
+ }
+
+ crt->version++;
+
+ if( ( ret = mbedtls_x509_get_sig_alg( &crt->sig_oid, &sig_params1,
+ &crt->sig_md, &crt->sig_pk,
+ &crt->sig_opts ) ) != 0 )
+ {
+ mbedtls_x509_crt_free( crt );
+ return( ret );
+ }
+
+ /*
+ * issuer Name
+ */
+ crt->issuer_raw.p = p;
+
+ if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
+ MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
+ {
+ mbedtls_x509_crt_free( crt );
+ return( MBEDTLS_ERR_X509_INVALID_FORMAT + ret );
+ }
+
+ if( ( ret = mbedtls_x509_get_name( &p, p + len, &crt->issuer ) ) != 0 )
+ {
+ mbedtls_x509_crt_free( crt );
+ return( ret );
+ }
+
+ crt->issuer_raw.len = p - crt->issuer_raw.p;
+
+ /*
+ * Validity ::= SEQUENCE {
+ * notBefore Time,
+ * notAfter Time }
+ *
+ */
+ if( ( ret = x509_get_dates( &p, end, &crt->valid_from,
+ &crt->valid_to ) ) != 0 )
+ {
+ mbedtls_x509_crt_free( crt );
+ return( ret );
+ }
+
+ /*
+ * subject Name
+ */
+ crt->subject_raw.p = p;
+
+ if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
+ MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
+ {
+ mbedtls_x509_crt_free( crt );
+ return( MBEDTLS_ERR_X509_INVALID_FORMAT + ret );
+ }
+
+ if( len && ( ret = mbedtls_x509_get_name( &p, p + len, &crt->subject ) ) != 0 )
+ {
+ mbedtls_x509_crt_free( crt );
+ return( ret );
+ }
+
+ crt->subject_raw.len = p - crt->subject_raw.p;
+
+ /*
+ * SubjectPublicKeyInfo
+ */
+ if( ( ret = mbedtls_pk_parse_subpubkey( &p, end, &crt->pk ) ) != 0 )
+ {
+ mbedtls_x509_crt_free( crt );
+ return( ret );
+ }
+
+ /*
+ * issuerUniqueID [1] IMPLICIT UniqueIdentifier OPTIONAL,
+ * -- If present, version shall be v2 or v3
+ * subjectUniqueID [2] IMPLICIT UniqueIdentifier OPTIONAL,
+ * -- If present, version shall be v2 or v3
+ * extensions [3] EXPLICIT Extensions OPTIONAL
+ * -- If present, version shall be v3
+ */
+ if( crt->version == 2 || crt->version == 3 )
+ {
+ ret = x509_get_uid( &p, end, &crt->issuer_id, 1 );
+ if( ret != 0 )
+ {
+ mbedtls_x509_crt_free( crt );
+ return( ret );
+ }
+ }
+
+ if( crt->version == 2 || crt->version == 3 )
+ {
+ ret = x509_get_uid( &p, end, &crt->subject_id, 2 );
+ if( ret != 0 )
+ {
+ mbedtls_x509_crt_free( crt );
+ return( ret );
+ }
+ }
+
+#if !defined(MBEDTLS_X509_ALLOW_EXTENSIONS_NON_V3)
+ if( crt->version == 3 )
+#endif
+ {
+ ret = x509_get_crt_ext( &p, end, crt );
+ if( ret != 0 )
+ {
+ mbedtls_x509_crt_free( crt );
+ return( ret );
+ }
+ }
+
+ if( p != end )
+ {
+ mbedtls_x509_crt_free( crt );
+ return( MBEDTLS_ERR_X509_INVALID_FORMAT +
+ MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
+ }
+
+ end = crt_end;
+
+ /*
+ * }
+ * -- end of TBSCertificate
+ *
+ * signatureAlgorithm AlgorithmIdentifier,
+ * signatureValue BIT STRING
+ */
+ if( ( ret = mbedtls_x509_get_alg( &p, end, &sig_oid2, &sig_params2 ) ) != 0 )
+ {
+ mbedtls_x509_crt_free( crt );
+ return( ret );
+ }
+
+ if( crt->sig_oid.len != sig_oid2.len ||
+ memcmp( crt->sig_oid.p, sig_oid2.p, crt->sig_oid.len ) != 0 ||
+ sig_params1.len != sig_params2.len ||
+ ( sig_params1.len != 0 &&
+ memcmp( sig_params1.p, sig_params2.p, sig_params1.len ) != 0 ) )
+ {
+ mbedtls_x509_crt_free( crt );
+ return( MBEDTLS_ERR_X509_SIG_MISMATCH );
+ }
+
+ if( ( ret = mbedtls_x509_get_sig( &p, end, &crt->sig ) ) != 0 )
+ {
+ mbedtls_x509_crt_free( crt );
+ return( ret );
+ }
+
+ if( p != end )
+ {
+ mbedtls_x509_crt_free( crt );
+ return( MBEDTLS_ERR_X509_INVALID_FORMAT +
+ MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
+ }
+
+ return( 0 );
+}
+
+/*
+ * Parse one X.509 certificate in DER format from a buffer and add them to a
+ * chained list
+ */
+int mbedtls_x509_crt_parse_der( mbedtls_x509_crt *chain, const unsigned char *buf,
+ size_t buflen )
+{
+ int ret;
+ mbedtls_x509_crt *crt = chain, *prev = NULL;
+
+ /*
+ * Check for valid input
+ */
+ if( crt == NULL || buf == NULL )
+ return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
+
+ while( crt->version != 0 && crt->next != NULL )
+ {
+ prev = crt;
+ crt = crt->next;
+ }
+
+ /*
+ * Add new certificate on the end of the chain if needed.
+ */
+ if( crt->version != 0 && crt->next == NULL )
+ {
+ crt->next = mbedtls_calloc( 1, sizeof( mbedtls_x509_crt ) );
+
+ if( crt->next == NULL )
+ return( MBEDTLS_ERR_X509_ALLOC_FAILED );
+
+ prev = crt;
+ mbedtls_x509_crt_init( crt->next );
+ crt = crt->next;
+ }
+
+ if( ( ret = x509_crt_parse_der_core( crt, buf, buflen ) ) != 0 )
+ {
+ if( prev )
+ prev->next = NULL;
+
+ if( crt != chain )
+ mbedtls_free( crt );
+
+ return( ret );
+ }
+
+ return( 0 );
+}
+
+/*
+ * Parse one or more PEM certificates from a buffer and add them to the chained
+ * list
+ */
+int mbedtls_x509_crt_parse( mbedtls_x509_crt *chain, const unsigned char *buf, size_t buflen )
+{
+#if defined(MBEDTLS_PEM_PARSE_C)
+ int success = 0, first_error = 0, total_failed = 0;
+ int buf_format = MBEDTLS_X509_FORMAT_DER;
+#endif
+
+ /*
+ * Check for valid input
+ */
+ if( chain == NULL || buf == NULL )
+ return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
+
+ /*
+ * Determine buffer content. Buffer contains either one DER certificate or
+ * one or more PEM certificates.
+ */
+#if defined(MBEDTLS_PEM_PARSE_C)
+ if( buflen != 0 && buf[buflen - 1] == '\0' &&
+ strstr( (const char *) buf, "-----BEGIN CERTIFICATE-----" ) != NULL )
+ {
+ buf_format = MBEDTLS_X509_FORMAT_PEM;
+ }
+
+ if( buf_format == MBEDTLS_X509_FORMAT_DER )
+ return mbedtls_x509_crt_parse_der( chain, buf, buflen );
+#else
+ return mbedtls_x509_crt_parse_der( chain, buf, buflen );
+#endif
+
+#if defined(MBEDTLS_PEM_PARSE_C)
+ if( buf_format == MBEDTLS_X509_FORMAT_PEM )
+ {
+ int ret;
+ mbedtls_pem_context pem;
+
+ /* 1 rather than 0 since the terminating NULL byte is counted in */
+ while( buflen > 1 )
+ {
+ size_t use_len;
+ mbedtls_pem_init( &pem );
+
+ /* If we get there, we know the string is null-terminated */
+ ret = mbedtls_pem_read_buffer( &pem,
+ "-----BEGIN CERTIFICATE-----",
+ "-----END CERTIFICATE-----",
+ buf, NULL, 0, &use_len );
+
+ if( ret == 0 )
+ {
+ /*
+ * Was PEM encoded
+ */
+ buflen -= use_len;
+ buf += use_len;
+ }
+ else if( ret == MBEDTLS_ERR_PEM_BAD_INPUT_DATA )
+ {
+ return( ret );
+ }
+ else if( ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT )
+ {
+ mbedtls_pem_free( &pem );
+
+ /*
+ * PEM header and footer were found
+ */
+ buflen -= use_len;
+ buf += use_len;
+
+ if( first_error == 0 )
+ first_error = ret;
+
+ total_failed++;
+ continue;
+ }
+ else
+ break;
+
+ ret = mbedtls_x509_crt_parse_der( chain, pem.buf, pem.buflen );
+
+ mbedtls_pem_free( &pem );
+
+ if( ret != 0 )
+ {
+ /*
+ * Quit parsing on a memory error
+ */
+ if( ret == MBEDTLS_ERR_X509_ALLOC_FAILED )
+ return( ret );
+
+ if( first_error == 0 )
+ first_error = ret;
+
+ total_failed++;
+ continue;
+ }
+
+ success = 1;
+ }
+ }
+
+ if( success )
+ return( total_failed );
+ else if( first_error )
+ return( first_error );
+ else
+ return( MBEDTLS_ERR_X509_CERT_UNKNOWN_FORMAT );
+#endif /* MBEDTLS_PEM_PARSE_C */
+}
+
+#if defined(MBEDTLS_FS_IO)
+/*
+ * Load one or more certificates and add them to the chained list
+ */
+int mbedtls_x509_crt_parse_file( mbedtls_x509_crt *chain, const char *path )
+{
+ int ret;
+ size_t n;
+ unsigned char *buf;
+
+ if( ( ret = mbedtls_pk_load_file( path, &buf, &n ) ) != 0 )
+ return( ret );
+
+ ret = mbedtls_x509_crt_parse( chain, buf, n );
+
+ mbedtls_platform_zeroize( buf, n );
+ mbedtls_free( buf );
+
+ return( ret );
+}
+
+int mbedtls_x509_crt_parse_path( mbedtls_x509_crt *chain, const char *path )
+{
+ int ret = 0;
+#if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32)
+ int w_ret;
+ WCHAR szDir[MAX_PATH];
+ char filename[MAX_PATH];
+ char *p;
+ size_t len = strlen( path );
+
+ WIN32_FIND_DATAW file_data;
+ HANDLE hFind;
+
+ if( len > MAX_PATH - 3 )
+ return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
+
+ memset( szDir, 0, sizeof(szDir) );
+ memset( filename, 0, MAX_PATH );
+ memcpy( filename, path, len );
+ filename[len++] = '\\';
+ p = filename + len;
+ filename[len++] = '*';
+
+ w_ret = MultiByteToWideChar( CP_ACP, 0, filename, (int)len, szDir,
+ MAX_PATH - 3 );
+ if( w_ret == 0 )
+ return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
+
+ hFind = FindFirstFileW( szDir, &file_data );
+ if( hFind == INVALID_HANDLE_VALUE )
+ return( MBEDTLS_ERR_X509_FILE_IO_ERROR );
+
+ len = MAX_PATH - len;
+ do
+ {
+ memset( p, 0, len );
+
+ if( file_data.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY )
+ continue;
+
+ w_ret = WideCharToMultiByte( CP_ACP, 0, file_data.cFileName,
+ lstrlenW( file_data.cFileName ),
+ p, (int) len - 1,
+ NULL, NULL );
+ if( w_ret == 0 )
+ {
+ ret = MBEDTLS_ERR_X509_FILE_IO_ERROR;
+ goto cleanup;
+ }
+
+ w_ret = mbedtls_x509_crt_parse_file( chain, filename );
+ if( w_ret < 0 )
+ ret++;
+ else
+ ret += w_ret;
+ }
+ while( FindNextFileW( hFind, &file_data ) != 0 );
+
+ if( GetLastError() != ERROR_NO_MORE_FILES )
+ ret = MBEDTLS_ERR_X509_FILE_IO_ERROR;
+
+cleanup:
+ FindClose( hFind );
+#else /* _WIN32 */
+ int t_ret;
+ int snp_ret;
+ struct stat sb;
+ struct dirent *entry;
+ char entry_name[MBEDTLS_X509_MAX_FILE_PATH_LEN];
+ DIR *dir = opendir( path );
+
+ if( dir == NULL )
+ return( MBEDTLS_ERR_X509_FILE_IO_ERROR );
+
+#if defined(MBEDTLS_THREADING_C)
+ if( ( ret = mbedtls_mutex_lock( &mbedtls_threading_readdir_mutex ) ) != 0 )
+ {
+ closedir( dir );
+ return( ret );
+ }
+#endif /* MBEDTLS_THREADING_C */
+
+ while( ( entry = readdir( dir ) ) != NULL )
+ {
+ snp_ret = mbedtls_snprintf( entry_name, sizeof entry_name,
+ "%s/%s", path, entry->d_name );
+
+ if( snp_ret < 0 || (size_t)snp_ret >= sizeof entry_name )
+ {
+ ret = MBEDTLS_ERR_X509_BUFFER_TOO_SMALL;
+ goto cleanup;
+ }
+ else if( stat( entry_name, &sb ) == -1 )
+ {
+ ret = MBEDTLS_ERR_X509_FILE_IO_ERROR;
+ goto cleanup;
+ }
+
+ if( !S_ISREG( sb.st_mode ) )
+ continue;
+
+ // Ignore parse errors
+ //
+ t_ret = mbedtls_x509_crt_parse_file( chain, entry_name );
+ if( t_ret < 0 )
+ ret++;
+ else
+ ret += t_ret;
+ }
+
+cleanup:
+ closedir( dir );
+
+#if defined(MBEDTLS_THREADING_C)
+ if( mbedtls_mutex_unlock( &mbedtls_threading_readdir_mutex ) != 0 )
+ ret = MBEDTLS_ERR_THREADING_MUTEX_ERROR;
+#endif /* MBEDTLS_THREADING_C */
+
+#endif /* _WIN32 */
+
+ return( ret );
+}
+#endif /* MBEDTLS_FS_IO */
+
+static int x509_info_subject_alt_name( char **buf, size_t *size,
+ const mbedtls_x509_sequence *subject_alt_name )
+{
+ size_t i;
+ size_t n = *size;
+ char *p = *buf;
+ const mbedtls_x509_sequence *cur = subject_alt_name;
+ const char *sep = "";
+ size_t sep_len = 0;
+
+ while( cur != NULL )
+ {
+ if( cur->buf.len + sep_len >= n )
+ {
+ *p = '\0';
+ return( MBEDTLS_ERR_X509_BUFFER_TOO_SMALL );
+ }
+
+ n -= cur->buf.len + sep_len;
+ for( i = 0; i < sep_len; i++ )
+ *p++ = sep[i];
+ for( i = 0; i < cur->buf.len; i++ )
+ *p++ = cur->buf.p[i];
+
+ sep = ", ";
+ sep_len = 2;
+
+ cur = cur->next;
+ }
+
+ *p = '\0';
+
+ *size = n;
+ *buf = p;
+
+ return( 0 );
+}
+
+#define PRINT_ITEM(i) \
+ { \
+ ret = mbedtls_snprintf( p, n, "%s" i, sep ); \
+ MBEDTLS_X509_SAFE_SNPRINTF; \
+ sep = ", "; \
+ }
+
+#define CERT_TYPE(type,name) \
+ if( ns_cert_type & type ) \
+ PRINT_ITEM( name );
+
+static int x509_info_cert_type( char **buf, size_t *size,
+ unsigned char ns_cert_type )
+{
+ int ret;
+ size_t n = *size;
+ char *p = *buf;
+ const char *sep = "";
+
+ CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_SSL_CLIENT, "SSL Client" );
+ CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_SSL_SERVER, "SSL Server" );
+ CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_EMAIL, "Email" );
+ CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_OBJECT_SIGNING, "Object Signing" );
+ CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_RESERVED, "Reserved" );
+ CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_SSL_CA, "SSL CA" );
+ CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_EMAIL_CA, "Email CA" );
+ CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_OBJECT_SIGNING_CA, "Object Signing CA" );
+
+ *size = n;
+ *buf = p;
+
+ return( 0 );
+}
+
+#define KEY_USAGE(code,name) \
+ if( key_usage & code ) \
+ PRINT_ITEM( name );
+
+static int x509_info_key_usage( char **buf, size_t *size,
+ unsigned int key_usage )
+{
+ int ret;
+ size_t n = *size;
+ char *p = *buf;
+ const char *sep = "";
+
+ KEY_USAGE( MBEDTLS_X509_KU_DIGITAL_SIGNATURE, "Digital Signature" );
+ KEY_USAGE( MBEDTLS_X509_KU_NON_REPUDIATION, "Non Repudiation" );
+ KEY_USAGE( MBEDTLS_X509_KU_KEY_ENCIPHERMENT, "Key Encipherment" );
+ KEY_USAGE( MBEDTLS_X509_KU_DATA_ENCIPHERMENT, "Data Encipherment" );
+ KEY_USAGE( MBEDTLS_X509_KU_KEY_AGREEMENT, "Key Agreement" );
+ KEY_USAGE( MBEDTLS_X509_KU_KEY_CERT_SIGN, "Key Cert Sign" );
+ KEY_USAGE( MBEDTLS_X509_KU_CRL_SIGN, "CRL Sign" );
+ KEY_USAGE( MBEDTLS_X509_KU_ENCIPHER_ONLY, "Encipher Only" );
+ KEY_USAGE( MBEDTLS_X509_KU_DECIPHER_ONLY, "Decipher Only" );
+
+ *size = n;
+ *buf = p;
+
+ return( 0 );
+}
+
+static int x509_info_ext_key_usage( char **buf, size_t *size,
+ const mbedtls_x509_sequence *extended_key_usage )
+{
+ int ret;
+ const char *desc;
+ size_t n = *size;
+ char *p = *buf;
+ const mbedtls_x509_sequence *cur = extended_key_usage;
+ const char *sep = "";
+
+ while( cur != NULL )
+ {
+ if( mbedtls_oid_get_extended_key_usage( &cur->buf, &desc ) != 0 )
+ desc = "???";
+
+ ret = mbedtls_snprintf( p, n, "%s%s", sep, desc );
+ MBEDTLS_X509_SAFE_SNPRINTF;
+
+ sep = ", ";
+
+ cur = cur->next;
+ }
+
+ *size = n;
+ *buf = p;
+
+ return( 0 );
+}
+
+/*
+ * Return an informational string about the certificate.
+ */
+#define BEFORE_COLON 18
+#define BC "18"
+int mbedtls_x509_crt_info( char *buf, size_t size, const char *prefix,
+ const mbedtls_x509_crt *crt )
+{
+ int ret;
+ size_t n;
+ char *p;
+ char key_size_str[BEFORE_COLON];
+
+ p = buf;
+ n = size;
+
+ if( NULL == crt )
+ {
+ ret = mbedtls_snprintf( p, n, "\nCertificate is uninitialised!\n" );
+ MBEDTLS_X509_SAFE_SNPRINTF;
+
+ return( (int) ( size - n ) );
+ }
+
+ ret = mbedtls_snprintf( p, n, "%scert. version : %d\n",
+ prefix, crt->version );
+ MBEDTLS_X509_SAFE_SNPRINTF;
+ ret = mbedtls_snprintf( p, n, "%sserial number : ",
+ prefix );
+ MBEDTLS_X509_SAFE_SNPRINTF;
+
+ ret = mbedtls_x509_serial_gets( p, n, &crt->serial );
+ MBEDTLS_X509_SAFE_SNPRINTF;
+
+ ret = mbedtls_snprintf( p, n, "\n%sissuer name : ", prefix );
+ MBEDTLS_X509_SAFE_SNPRINTF;
+ ret = mbedtls_x509_dn_gets( p, n, &crt->issuer );
+ MBEDTLS_X509_SAFE_SNPRINTF;
+
+ ret = mbedtls_snprintf( p, n, "\n%ssubject name : ", prefix );
+ MBEDTLS_X509_SAFE_SNPRINTF;
+ ret = mbedtls_x509_dn_gets( p, n, &crt->subject );
+ MBEDTLS_X509_SAFE_SNPRINTF;
+
+ ret = mbedtls_snprintf( p, n, "\n%sissued on : " \
+ "%04d-%02d-%02d %02d:%02d:%02d", prefix,
+ crt->valid_from.year, crt->valid_from.mon,
+ crt->valid_from.day, crt->valid_from.hour,
+ crt->valid_from.min, crt->valid_from.sec );
+ MBEDTLS_X509_SAFE_SNPRINTF;
+
+ ret = mbedtls_snprintf( p, n, "\n%sexpires on : " \
+ "%04d-%02d-%02d %02d:%02d:%02d", prefix,
+ crt->valid_to.year, crt->valid_to.mon,
+ crt->valid_to.day, crt->valid_to.hour,
+ crt->valid_to.min, crt->valid_to.sec );
+ MBEDTLS_X509_SAFE_SNPRINTF;
+
+ ret = mbedtls_snprintf( p, n, "\n%ssigned using : ", prefix );
+ MBEDTLS_X509_SAFE_SNPRINTF;
+
+ ret = mbedtls_x509_sig_alg_gets( p, n, &crt->sig_oid, crt->sig_pk,
+ crt->sig_md, crt->sig_opts );
+ MBEDTLS_X509_SAFE_SNPRINTF;
+
+ /* Key size */
+ if( ( ret = mbedtls_x509_key_size_helper( key_size_str, BEFORE_COLON,
+ mbedtls_pk_get_name( &crt->pk ) ) ) != 0 )
+ {
+ return( ret );
+ }
+
+ ret = mbedtls_snprintf( p, n, "\n%s%-" BC "s: %d bits", prefix, key_size_str,
+ (int) mbedtls_pk_get_bitlen( &crt->pk ) );
+ MBEDTLS_X509_SAFE_SNPRINTF;
+
+ /*
+ * Optional extensions
+ */
+
+ if( crt->ext_types & MBEDTLS_X509_EXT_BASIC_CONSTRAINTS )
+ {
+ ret = mbedtls_snprintf( p, n, "\n%sbasic constraints : CA=%s", prefix,
+ crt->ca_istrue ? "true" : "false" );
+ MBEDTLS_X509_SAFE_SNPRINTF;
+
+ if( crt->max_pathlen > 0 )
+ {
+ ret = mbedtls_snprintf( p, n, ", max_pathlen=%d", crt->max_pathlen - 1 );
+ MBEDTLS_X509_SAFE_SNPRINTF;
+ }
+ }
+
+ if( crt->ext_types & MBEDTLS_X509_EXT_SUBJECT_ALT_NAME )
+ {
+ ret = mbedtls_snprintf( p, n, "\n%ssubject alt name : ", prefix );
+ MBEDTLS_X509_SAFE_SNPRINTF;
+
+ if( ( ret = x509_info_subject_alt_name( &p, &n,
+ &crt->subject_alt_names ) ) != 0 )
+ return( ret );
+ }
+
+ if( crt->ext_types & MBEDTLS_X509_EXT_NS_CERT_TYPE )
+ {
+ ret = mbedtls_snprintf( p, n, "\n%scert. type : ", prefix );
+ MBEDTLS_X509_SAFE_SNPRINTF;
+
+ if( ( ret = x509_info_cert_type( &p, &n, crt->ns_cert_type ) ) != 0 )
+ return( ret );
+ }
+
+ if( crt->ext_types & MBEDTLS_X509_EXT_KEY_USAGE )
+ {
+ ret = mbedtls_snprintf( p, n, "\n%skey usage : ", prefix );
+ MBEDTLS_X509_SAFE_SNPRINTF;
+
+ if( ( ret = x509_info_key_usage( &p, &n, crt->key_usage ) ) != 0 )
+ return( ret );
+ }
+
+ if( crt->ext_types & MBEDTLS_X509_EXT_EXTENDED_KEY_USAGE )
+ {
+ ret = mbedtls_snprintf( p, n, "\n%sext key usage : ", prefix );
+ MBEDTLS_X509_SAFE_SNPRINTF;
+
+ if( ( ret = x509_info_ext_key_usage( &p, &n,
+ &crt->ext_key_usage ) ) != 0 )
+ return( ret );
+ }
+
+ ret = mbedtls_snprintf( p, n, "\n" );
+ MBEDTLS_X509_SAFE_SNPRINTF;
+
+ return( (int) ( size - n ) );
+}
+
+struct x509_crt_verify_string {
+ int code;
+ const char *string;
+};
+
+static const struct x509_crt_verify_string x509_crt_verify_strings[] = {
+ { MBEDTLS_X509_BADCERT_EXPIRED, "The certificate validity has expired" },
+ { MBEDTLS_X509_BADCERT_REVOKED, "The certificate has been revoked (is on a CRL)" },
+ { MBEDTLS_X509_BADCERT_CN_MISMATCH, "The certificate Common Name (CN) does not match with the expected CN" },
+ { MBEDTLS_X509_BADCERT_NOT_TRUSTED, "The certificate is not correctly signed by the trusted CA" },
+ { MBEDTLS_X509_BADCRL_NOT_TRUSTED, "The CRL is not correctly signed by the trusted CA" },
+ { MBEDTLS_X509_BADCRL_EXPIRED, "The CRL is expired" },
+ { MBEDTLS_X509_BADCERT_MISSING, "Certificate was missing" },
+ { MBEDTLS_X509_BADCERT_SKIP_VERIFY, "Certificate verification was skipped" },
+ { MBEDTLS_X509_BADCERT_OTHER, "Other reason (can be used by verify callback)" },
+ { MBEDTLS_X509_BADCERT_FUTURE, "The certificate validity starts in the future" },
+ { MBEDTLS_X509_BADCRL_FUTURE, "The CRL is from the future" },
+ { MBEDTLS_X509_BADCERT_KEY_USAGE, "Usage does not match the keyUsage extension" },
+ { MBEDTLS_X509_BADCERT_EXT_KEY_USAGE, "Usage does not match the extendedKeyUsage extension" },
+ { MBEDTLS_X509_BADCERT_NS_CERT_TYPE, "Usage does not match the nsCertType extension" },
+ { MBEDTLS_X509_BADCERT_BAD_MD, "The certificate is signed with an unacceptable hash." },
+ { MBEDTLS_X509_BADCERT_BAD_PK, "The certificate is signed with an unacceptable PK alg (eg RSA vs ECDSA)." },
+ { MBEDTLS_X509_BADCERT_BAD_KEY, "The certificate is signed with an unacceptable key (eg bad curve, RSA too short)." },
+ { MBEDTLS_X509_BADCRL_BAD_MD, "The CRL is signed with an unacceptable hash." },
+ { MBEDTLS_X509_BADCRL_BAD_PK, "The CRL is signed with an unacceptable PK alg (eg RSA vs ECDSA)." },
+ { MBEDTLS_X509_BADCRL_BAD_KEY, "The CRL is signed with an unacceptable key (eg bad curve, RSA too short)." },
+ { 0, NULL }
+};
+
+int mbedtls_x509_crt_verify_info( char *buf, size_t size, const char *prefix,
+ uint32_t flags )
+{
+ int ret;
+ const struct x509_crt_verify_string *cur;
+ char *p = buf;
+ size_t n = size;
+
+ for( cur = x509_crt_verify_strings; cur->string != NULL ; cur++ )
+ {
+ if( ( flags & cur->code ) == 0 )
+ continue;
+
+ ret = mbedtls_snprintf( p, n, "%s%s\n", prefix, cur->string );
+ MBEDTLS_X509_SAFE_SNPRINTF;
+ flags ^= cur->code;
+ }
+
+ if( flags != 0 )
+ {
+ ret = mbedtls_snprintf( p, n, "%sUnknown reason "
+ "(this should not happen)\n", prefix );
+ MBEDTLS_X509_SAFE_SNPRINTF;
+ }
+
+ return( (int) ( size - n ) );
+}
+
+#if defined(MBEDTLS_X509_CHECK_KEY_USAGE)
+int mbedtls_x509_crt_check_key_usage( const mbedtls_x509_crt *crt,
+ unsigned int usage )
+{
+ unsigned int usage_must, usage_may;
+ unsigned int may_mask = MBEDTLS_X509_KU_ENCIPHER_ONLY
+ | MBEDTLS_X509_KU_DECIPHER_ONLY;
+
+ if( ( crt->ext_types & MBEDTLS_X509_EXT_KEY_USAGE ) == 0 )
+ return( 0 );
+
+ usage_must = usage & ~may_mask;
+
+ if( ( ( crt->key_usage & ~may_mask ) & usage_must ) != usage_must )
+ return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
+
+ usage_may = usage & may_mask;
+
+ if( ( ( crt->key_usage & may_mask ) | usage_may ) != usage_may )
+ return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
+
+ return( 0 );
+}
+#endif
+
+#if defined(MBEDTLS_X509_CHECK_EXTENDED_KEY_USAGE)
+int mbedtls_x509_crt_check_extended_key_usage( const mbedtls_x509_crt *crt,
+ const char *usage_oid,
+ size_t usage_len )
+{
+ const mbedtls_x509_sequence *cur;
+
+ /* Extension is not mandatory, absent means no restriction */
+ if( ( crt->ext_types & MBEDTLS_X509_EXT_EXTENDED_KEY_USAGE ) == 0 )
+ return( 0 );
+
+ /*
+ * Look for the requested usage (or wildcard ANY) in our list
+ */
+ for( cur = &crt->ext_key_usage; cur != NULL; cur = cur->next )
+ {
+ const mbedtls_x509_buf *cur_oid = &cur->buf;
+
+ if( cur_oid->len == usage_len &&
+ memcmp( cur_oid->p, usage_oid, usage_len ) == 0 )
+ {
+ return( 0 );
+ }
+
+ if( MBEDTLS_OID_CMP( MBEDTLS_OID_ANY_EXTENDED_KEY_USAGE, cur_oid ) == 0 )
+ return( 0 );
+ }
+
+ return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
+}
+#endif /* MBEDTLS_X509_CHECK_EXTENDED_KEY_USAGE */
+
+#if defined(MBEDTLS_X509_CRL_PARSE_C)
+/*
+ * Return 1 if the certificate is revoked, or 0 otherwise.
+ */
+int mbedtls_x509_crt_is_revoked( const mbedtls_x509_crt *crt, const mbedtls_x509_crl *crl )
+{
+ const mbedtls_x509_crl_entry *cur = &crl->entry;
+
+ while( cur != NULL && cur->serial.len != 0 )
+ {
+ if( crt->serial.len == cur->serial.len &&
+ memcmp( crt->serial.p, cur->serial.p, crt->serial.len ) == 0 )
+ {
+ if( mbedtls_x509_time_is_past( &cur->revocation_date ) )
+ return( 1 );
+ }
+
+ cur = cur->next;
+ }
+
+ return( 0 );
+}
+
+/*
+ * Check that the given certificate is not revoked according to the CRL.
+ * Skip validation if no CRL for the given CA is present.
+ */
+static int x509_crt_verifycrl( mbedtls_x509_crt *crt, mbedtls_x509_crt *ca,
+ mbedtls_x509_crl *crl_list,
+ const mbedtls_x509_crt_profile *profile )
+{
+ int flags = 0;
+ unsigned char hash[MBEDTLS_MD_MAX_SIZE];
+ const mbedtls_md_info_t *md_info;
+
+ if( ca == NULL )
+ return( flags );
+
+ while( crl_list != NULL )
+ {
+ if( crl_list->version == 0 ||
+ crl_list->issuer_raw.len != ca->subject_raw.len ||
+ memcmp( crl_list->issuer_raw.p, ca->subject_raw.p,
+ crl_list->issuer_raw.len ) != 0 )
+ {
+ crl_list = crl_list->next;
+ continue;
+ }
+
+ /*
+ * Check if the CA is configured to sign CRLs
+ */
+#if defined(MBEDTLS_X509_CHECK_KEY_USAGE)
+ if( mbedtls_x509_crt_check_key_usage( ca, MBEDTLS_X509_KU_CRL_SIGN ) != 0 )
+ {
+ flags |= MBEDTLS_X509_BADCRL_NOT_TRUSTED;
+ break;
+ }
+#endif
+
+ /*
+ * Check if CRL is correctly signed by the trusted CA
+ */
+ if( x509_profile_check_md_alg( profile, crl_list->sig_md ) != 0 )
+ flags |= MBEDTLS_X509_BADCRL_BAD_MD;
+
+ if( x509_profile_check_pk_alg( profile, crl_list->sig_pk ) != 0 )
+ flags |= MBEDTLS_X509_BADCRL_BAD_PK;
+
+ md_info = mbedtls_md_info_from_type( crl_list->sig_md );
+ if( mbedtls_md( md_info, crl_list->tbs.p, crl_list->tbs.len, hash ) != 0 )
+ {
+ /* Note: this can't happen except after an internal error */
+ flags |= MBEDTLS_X509_BADCRL_NOT_TRUSTED;
+ break;
+ }
+
+ if( x509_profile_check_key( profile, &ca->pk ) != 0 )
+ flags |= MBEDTLS_X509_BADCERT_BAD_KEY;
+
+ if( mbedtls_pk_verify_ext( crl_list->sig_pk, crl_list->sig_opts, &ca->pk,
+ crl_list->sig_md, hash, mbedtls_md_get_size( md_info ),
+ crl_list->sig.p, crl_list->sig.len ) != 0 )
+ {
+ flags |= MBEDTLS_X509_BADCRL_NOT_TRUSTED;
+ break;
+ }
+
+ /*
+ * Check for validity of CRL (Do not drop out)
+ */
+ if( mbedtls_x509_time_is_past( &crl_list->next_update ) )
+ flags |= MBEDTLS_X509_BADCRL_EXPIRED;
+
+ if( mbedtls_x509_time_is_future( &crl_list->this_update ) )
+ flags |= MBEDTLS_X509_BADCRL_FUTURE;
+
+ /*
+ * Check if certificate is revoked
+ */
+ if( mbedtls_x509_crt_is_revoked( crt, crl_list ) )
+ {
+ flags |= MBEDTLS_X509_BADCERT_REVOKED;
+ break;
+ }
+
+ crl_list = crl_list->next;
+ }
+
+ return( flags );
+}
+#endif /* MBEDTLS_X509_CRL_PARSE_C */
+
+/*
+ * Like memcmp, but case-insensitive and always returns -1 if different
+ */
+static int x509_memcasecmp( const void *s1, const void *s2, size_t len )
+{
+ size_t i;
+ unsigned char diff;
+ const unsigned char *n1 = s1, *n2 = s2;
+
+ for( i = 0; i < len; i++ )
+ {
+ diff = n1[i] ^ n2[i];
+
+ if( diff == 0 )
+ continue;
+
+ if( diff == 32 &&
+ ( ( n1[i] >= 'a' && n1[i] <= 'z' ) ||
+ ( n1[i] >= 'A' && n1[i] <= 'Z' ) ) )
+ {
+ continue;
+ }
+
+ return( -1 );
+ }
+
+ return( 0 );
+}
+
+/*
+ * Return 0 if name matches wildcard, -1 otherwise
+ */
+static int x509_check_wildcard( const char *cn, const mbedtls_x509_buf *name )
+{
+ size_t i;
+ size_t cn_idx = 0, cn_len = strlen( cn );
+
+ /* We can't have a match if there is no wildcard to match */
+ if( name->len < 3 || name->p[0] != '*' || name->p[1] != '.' )
+ return( -1 );
+
+ for( i = 0; i < cn_len; ++i )
+ {
+ if( cn[i] == '.' )
+ {
+ cn_idx = i;
+ break;
+ }
+ }
+
+ if( cn_idx == 0 )
+ return( -1 );
+
+ if( cn_len - cn_idx == name->len - 1 &&
+ x509_memcasecmp( name->p + 1, cn + cn_idx, name->len - 1 ) == 0 )
+ {
+ return( 0 );
+ }
+
+ return( -1 );
+}
+
+/*
+ * Compare two X.509 strings, case-insensitive, and allowing for some encoding
+ * variations (but not all).
+ *
+ * Return 0 if equal, -1 otherwise.
+ */
+static int x509_string_cmp( const mbedtls_x509_buf *a, const mbedtls_x509_buf *b )
+{
+ if( a->tag == b->tag &&
+ a->len == b->len &&
+ memcmp( a->p, b->p, b->len ) == 0 )
+ {
+ return( 0 );
+ }
+
+ if( ( a->tag == MBEDTLS_ASN1_UTF8_STRING || a->tag == MBEDTLS_ASN1_PRINTABLE_STRING ) &&
+ ( b->tag == MBEDTLS_ASN1_UTF8_STRING || b->tag == MBEDTLS_ASN1_PRINTABLE_STRING ) &&
+ a->len == b->len &&
+ x509_memcasecmp( a->p, b->p, b->len ) == 0 )
+ {
+ return( 0 );
+ }
+
+ return( -1 );
+}
+
+/*
+ * Compare two X.509 Names (aka rdnSequence).
+ *
+ * See RFC 5280 section 7.1, though we don't implement the whole algorithm:
+ * we sometimes return unequal when the full algorithm would return equal,
+ * but never the other way. (In particular, we don't do Unicode normalisation
+ * or space folding.)
+ *
+ * Return 0 if equal, -1 otherwise.
+ */
+static int x509_name_cmp( const mbedtls_x509_name *a, const mbedtls_x509_name *b )
+{
+ /* Avoid recursion, it might not be optimised by the compiler */
+ while( a != NULL || b != NULL )
+ {
+ if( a == NULL || b == NULL )
+ return( -1 );
+
+ /* type */
+ if( a->oid.tag != b->oid.tag ||
+ a->oid.len != b->oid.len ||
+ memcmp( a->oid.p, b->oid.p, b->oid.len ) != 0 )
+ {
+ return( -1 );
+ }
+
+ /* value */
+ if( x509_string_cmp( &a->val, &b->val ) != 0 )
+ return( -1 );
+
+ /* structure of the list of sets */
+ if( a->next_merged != b->next_merged )
+ return( -1 );
+
+ a = a->next;
+ b = b->next;
+ }
+
+ /* a == NULL == b */
+ return( 0 );
+}
+
+/*
+ * Check the signature of a certificate by its parent
+ */
+static int x509_crt_check_signature( const mbedtls_x509_crt *child,
+ mbedtls_x509_crt *parent )
+{
+ const mbedtls_md_info_t *md_info;
+ unsigned char hash[MBEDTLS_MD_MAX_SIZE];
+
+ md_info = mbedtls_md_info_from_type( child->sig_md );
+ if( mbedtls_md( md_info, child->tbs.p, child->tbs.len, hash ) != 0 )
+ {
+ /* Note: this can't happen except after an internal error */
+ return( -1 );
+ }
+
+ if( mbedtls_pk_verify_ext( child->sig_pk, child->sig_opts, &parent->pk,
+ child->sig_md, hash, mbedtls_md_get_size( md_info ),
+ child->sig.p, child->sig.len ) != 0 )
+ {
+ return( -1 );
+ }
+
+ return( 0 );
+}
+
+/*
+ * Check if 'parent' is a suitable parent (signing CA) for 'child'.
+ * Return 0 if yes, -1 if not.
+ *
+ * top means parent is a locally-trusted certificate
+ */
+static int x509_crt_check_parent( const mbedtls_x509_crt *child,
+ const mbedtls_x509_crt *parent,
+ int top )
+{
+ int need_ca_bit;
+
+ /* Parent must be the issuer */
+ if( x509_name_cmp( &child->issuer, &parent->subject ) != 0 )
+ return( -1 );
+
+ /* Parent must have the basicConstraints CA bit set as a general rule */
+ need_ca_bit = 1;
+
+ /* Exception: v1/v2 certificates that are locally trusted. */
+ if( top && parent->version < 3 )
+ need_ca_bit = 0;
+
+ if( need_ca_bit && ! parent->ca_istrue )
+ return( -1 );
+
+#if defined(MBEDTLS_X509_CHECK_KEY_USAGE)
+ if( need_ca_bit &&
+ mbedtls_x509_crt_check_key_usage( parent, MBEDTLS_X509_KU_KEY_CERT_SIGN ) != 0 )
+ {
+ return( -1 );
+ }
+#endif
+
+ return( 0 );
+}
+
+/*
+ * Find a suitable parent for child in candidates, or return NULL.
+ *
+ * Here suitable is defined as:
+ * 1. subject name matches child's issuer
+ * 2. if necessary, the CA bit is set and key usage allows signing certs
+ * 3. for trusted roots, the signature is correct
+ * 4. pathlen constraints are satisfied
+ *
+ * If there's a suitable candidate which is also time-valid, return the first
+ * such. Otherwise, return the first suitable candidate (or NULL if there is
+ * none).
+ *
+ * The rationale for this rule is that someone could have a list of trusted
+ * roots with two versions on the same root with different validity periods.
+ * (At least one user reported having such a list and wanted it to just work.)
+ * The reason we don't just require time-validity is that generally there is
+ * only one version, and if it's expired we want the flags to state that
+ * rather than NOT_TRUSTED, as would be the case if we required it here.
+ *
+ * The rationale for rule 3 (signature for trusted roots) is that users might
+ * have two versions of the same CA with different keys in their list, and the
+ * way we select the correct one is by checking the signature (as we don't
+ * rely on key identifier extensions). (This is one way users might choose to
+ * handle key rollover, another relies on self-issued certs, see [SIRO].)
+ *
+ * Arguments:
+ * - [in] child: certificate for which we're looking for a parent
+ * - [in] candidates: chained list of potential parents
+ * - [in] top: 1 if candidates consists of trusted roots, ie we're at the top
+ * of the chain, 0 otherwise
+ * - [in] path_cnt: number of intermediates seen so far
+ * - [in] self_cnt: number of self-signed intermediates seen so far
+ * (will never be greater than path_cnt)
+ *
+ * Return value:
+ * - the first suitable parent found (see above regarding time-validity)
+ * - NULL if no suitable parent was found
+ */
+static mbedtls_x509_crt *x509_crt_find_parent_in( mbedtls_x509_crt *child,
+ mbedtls_x509_crt *candidates,
+ int top,
+ size_t path_cnt,
+ size_t self_cnt )
+{
+ mbedtls_x509_crt *parent, *badtime_parent = NULL;
+
+ for( parent = candidates; parent != NULL; parent = parent->next )
+ {
+ /* basic parenting skills (name, CA bit, key usage) */
+ if( x509_crt_check_parent( child, parent, top ) != 0 )
+ continue;
+
+ /* +1 because stored max_pathlen is 1 higher that the actual value */
+ if( parent->max_pathlen > 0 &&
+ (size_t) parent->max_pathlen < 1 + path_cnt - self_cnt )
+ {
+ continue;
+ }
+
+ /* Signature */
+ if( top && x509_crt_check_signature( child, parent ) != 0 )
+ {
+ continue;
+ }
+
+ /* optional time check */
+ if( mbedtls_x509_time_is_past( &parent->valid_to ) ||
+ mbedtls_x509_time_is_future( &parent->valid_from ) )
+ {
+ if( badtime_parent == NULL )
+ badtime_parent = parent;
+
+ continue;
+ }
+
+ break;
+ }
+
+ if( parent == NULL )
+ parent = badtime_parent;
+
+ return( parent );
+}
+
+/*
+ * Find a parent in trusted CAs or the provided chain, or return NULL.
+ *
+ * Searches in trusted CAs first, and return the first suitable parent found
+ * (see find_parent_in() for definition of suitable).
+ *
+ * Arguments:
+ * - [in] child: certificate for which we're looking for a parent, followed
+ * by a chain of possible intermediates
+ * - [in] trust_ca: locally trusted CAs
+ * - [out] 1 if parent was found in trust_ca, 0 if found in provided chain
+ * - [in] path_cnt: number of intermediates seen so far
+ * - [in] self_cnt: number of self-signed intermediates seen so far
+ * (will always be no greater than path_cnt)
+ *
+ * Return value:
+ * - the first suitable parent found (see find_parent_in() for "suitable")
+ * - NULL if no suitable parent was found
+ */
+static mbedtls_x509_crt *x509_crt_find_parent( mbedtls_x509_crt *child,
+ mbedtls_x509_crt *trust_ca,
+ int *parent_is_trusted,
+ size_t path_cnt,
+ size_t self_cnt )
+{
+ mbedtls_x509_crt *parent;
+
+ /* Look for a parent in trusted CAs */
+ *parent_is_trusted = 1;
+ parent = x509_crt_find_parent_in( child, trust_ca, 1, path_cnt, self_cnt );
+
+ if( parent != NULL )
+ return( parent );
+
+ /* Look for a parent upwards the chain */
+ *parent_is_trusted = 0;
+ return( x509_crt_find_parent_in( child, child->next, 0, path_cnt, self_cnt ) );
+}
+
+/*
+ * Check if an end-entity certificate is locally trusted
+ *
+ * Currently we require such certificates to be self-signed (actually only
+ * check for self-issued as self-signatures are not checked)
+ */
+static int x509_crt_check_ee_locally_trusted(
+ mbedtls_x509_crt *crt,
+ mbedtls_x509_crt *trust_ca )
+{
+ mbedtls_x509_crt *cur;
+
+ /* must be self-issued */
+ if( x509_name_cmp( &crt->issuer, &crt->subject ) != 0 )
+ return( -1 );
+
+ /* look for an exact match with trusted cert */
+ for( cur = trust_ca; cur != NULL; cur = cur->next )
+ {
+ if( crt->raw.len == cur->raw.len &&
+ memcmp( crt->raw.p, cur->raw.p, crt->raw.len ) == 0 )
+ {
+ return( 0 );
+ }
+ }
+
+ /* too bad */
+ return( -1 );
+}
+
+/*
+ * Build and verify a certificate chain
+ *
+ * Given a peer-provided list of certificates EE, C1, ..., Cn and
+ * a list of trusted certs R1, ... Rp, try to build and verify a chain
+ * EE, Ci1, ... Ciq [, Rj]
+ * such that every cert in the chain is a child of the next one,
+ * jumping to a trusted root as early as possible.
+ *
+ * Verify that chain and return it with flags for all issues found.
+ *
+ * Special cases:
+ * - EE == Rj -> return a one-element list containing it
+ * - EE, Ci1, ..., Ciq cannot be continued with a trusted root
+ * -> return that chain with NOT_TRUSTED set on Ciq
+ *
+ * Arguments:
+ * - [in] crt: the cert list EE, C1, ..., Cn
+ * - [in] trust_ca: the trusted list R1, ..., Rp
+ * - [in] ca_crl, profile: as in verify_with_profile()
+ * - [out] ver_chain, chain_len: the built and verified chain
+ *
+ * Return value:
+ * - non-zero if the chain could not be fully built and examined
+ * - 0 is the chain was successfully built and examined,
+ * even if it was found to be invalid
+ */
+static int x509_crt_verify_chain(
+ mbedtls_x509_crt *crt,
+ mbedtls_x509_crt *trust_ca,
+ mbedtls_x509_crl *ca_crl,
+ const mbedtls_x509_crt_profile *profile,
+ x509_crt_verify_chain_item ver_chain[X509_MAX_VERIFY_CHAIN_SIZE],
+ size_t *chain_len )
+{
+ uint32_t *flags;
+ mbedtls_x509_crt *child;
+ mbedtls_x509_crt *parent;
+ int parent_is_trusted = 0;
+ int child_is_trusted = 0;
+ size_t self_cnt = 0;
+
+ child = crt;
+ *chain_len = 0;
+
+ while( 1 ) {
+ /* Add certificate to the verification chain */
+ ver_chain[*chain_len].crt = child;
+ flags = &ver_chain[*chain_len].flags;
+ ++*chain_len;
+
+ /* Check time-validity (all certificates) */
+ if( mbedtls_x509_time_is_past( &child->valid_to ) )
+ *flags |= MBEDTLS_X509_BADCERT_EXPIRED;
+
+ if( mbedtls_x509_time_is_future( &child->valid_from ) )
+ *flags |= MBEDTLS_X509_BADCERT_FUTURE;
+
+ /* Stop here for trusted roots (but not for trusted EE certs) */
+ if( child_is_trusted )
+ return( 0 );
+
+ /* Check signature algorithm: MD & PK algs */
+ if( x509_profile_check_md_alg( profile, child->sig_md ) != 0 )
+ *flags |= MBEDTLS_X509_BADCERT_BAD_MD;
+
+ if( x509_profile_check_pk_alg( profile, child->sig_pk ) != 0 )
+ *flags |= MBEDTLS_X509_BADCERT_BAD_PK;
+
+ /* Special case: EE certs that are locally trusted */
+ if( *chain_len == 1 &&
+ x509_crt_check_ee_locally_trusted( child, trust_ca ) == 0 )
+ {
+ return( 0 );
+ }
+
+ /* Look for a parent in trusted CAs or up the chain */
+ parent = x509_crt_find_parent( child, trust_ca, &parent_is_trusted,
+ *chain_len - 1, self_cnt );
+
+ /* No parent? We're done here */
+ if( parent == NULL )
+ {
+ *flags |= MBEDTLS_X509_BADCERT_NOT_TRUSTED;
+ return( 0 );
+ }
+
+ /* Count intermediate self-issued (not necessarily self-signed) certs.
+ * These can occur with some strategies for key rollover, see [SIRO],
+ * and should be excluded from max_pathlen checks. */
+ if( *chain_len != 1 &&
+ x509_name_cmp( &child->issuer, &child->subject ) == 0 )
+ {
+ self_cnt++;
+ }
+
+ /* path_cnt is 0 for the first intermediate CA,
+ * and if parent is trusted it's not an intermediate CA */
+ if( ! parent_is_trusted &&
+ *chain_len > MBEDTLS_X509_MAX_INTERMEDIATE_CA )
+ {
+ /* return immediately to avoid overflow the chain array */
+ return( MBEDTLS_ERR_X509_FATAL_ERROR );
+ }
+
+ /* if parent is trusted, the signature was checked by find_parent() */
+ if( ! parent_is_trusted && x509_crt_check_signature( child, parent ) != 0 )
+ *flags |= MBEDTLS_X509_BADCERT_NOT_TRUSTED;
+
+ /* check size of signing key */
+ if( x509_profile_check_key( profile, &parent->pk ) != 0 )
+ *flags |= MBEDTLS_X509_BADCERT_BAD_KEY;
+
+#if defined(MBEDTLS_X509_CRL_PARSE_C)
+ /* Check trusted CA's CRL for the given crt */
+ *flags |= x509_crt_verifycrl( child, parent, ca_crl, profile );
+#else
+ (void) ca_crl;
+#endif
+
+ /* prepare for next iteration */
+ child = parent;
+ parent = NULL;
+ child_is_trusted = parent_is_trusted;
+ }
+}
+
+/*
+ * Check for CN match
+ */
+static int x509_crt_check_cn( const mbedtls_x509_buf *name,
+ const char *cn, size_t cn_len )
+{
+ /* try exact match */
+ if( name->len == cn_len &&
+ x509_memcasecmp( cn, name->p, cn_len ) == 0 )
+ {
+ return( 0 );
+ }
+
+ /* try wildcard match */
+ if( x509_check_wildcard( cn, name ) == 0 )
+ {
+ return( 0 );
+ }
+
+ return( -1 );
+}
+
+/*
+ * Verify the requested CN - only call this if cn is not NULL!
+ */
+static void x509_crt_verify_name( const mbedtls_x509_crt *crt,
+ const char *cn,
+ uint32_t *flags )
+{
+ const mbedtls_x509_name *name;
+ const mbedtls_x509_sequence *cur;
+ size_t cn_len = strlen( cn );
+
+ if( crt->ext_types & MBEDTLS_X509_EXT_SUBJECT_ALT_NAME )
+ {
+ for( cur = &crt->subject_alt_names; cur != NULL; cur = cur->next )
+ {
+ if( x509_crt_check_cn( &cur->buf, cn, cn_len ) == 0 )
+ break;
+ }
+
+ if( cur == NULL )
+ *flags |= MBEDTLS_X509_BADCERT_CN_MISMATCH;
+ }
+ else
+ {
+ for( name = &crt->subject; name != NULL; name = name->next )
+ {
+ if( MBEDTLS_OID_CMP( MBEDTLS_OID_AT_CN, &name->oid ) == 0 &&
+ x509_crt_check_cn( &name->val, cn, cn_len ) == 0 )
+ {
+ break;
+ }
+ }
+
+ if( name == NULL )
+ *flags |= MBEDTLS_X509_BADCERT_CN_MISMATCH;
+ }
+}
+
+/*
+ * Merge the flags for all certs in the chain, after calling callback
+ */
+static int x509_crt_merge_flags_with_cb(
+ uint32_t *flags,
+ x509_crt_verify_chain_item ver_chain[X509_MAX_VERIFY_CHAIN_SIZE],
+ size_t chain_len,
+ int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
+ void *p_vrfy )
+{
+ int ret;
+ size_t i;
+ uint32_t cur_flags;
+
+ for( i = chain_len; i != 0; --i )
+ {
+ cur_flags = ver_chain[i-1].flags;
+
+ if( NULL != f_vrfy )
+ if( ( ret = f_vrfy( p_vrfy, ver_chain[i-1].crt, (int) i-1, &cur_flags ) ) != 0 )
+ return( ret );
+
+ *flags |= cur_flags;
+ }
+
+ return( 0 );
+}
+
+/*
+ * Verify the certificate validity
+ */
+int mbedtls_x509_crt_verify( mbedtls_x509_crt *crt,
+ mbedtls_x509_crt *trust_ca,
+ mbedtls_x509_crl *ca_crl,
+ const char *cn, uint32_t *flags,
+ int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
+ void *p_vrfy )
+{
+ return( mbedtls_x509_crt_verify_with_profile( crt, trust_ca, ca_crl,
+ &mbedtls_x509_crt_profile_default, cn, flags, f_vrfy, p_vrfy ) );
+}
+
+/*
+ * Verify the certificate validity, with profile
+ *
+ * This function:
+ * - checks the requested CN (if any)
+ * - checks the type and size of the EE cert's key,
+ * as that isn't done as part of chain building/verification currently
+ * - builds and verifies the chain
+ * - then calls the callback and merges the flags
+ */
+int mbedtls_x509_crt_verify_with_profile( mbedtls_x509_crt *crt,
+ mbedtls_x509_crt *trust_ca,
+ mbedtls_x509_crl *ca_crl,
+ const mbedtls_x509_crt_profile *profile,
+ const char *cn, uint32_t *flags,
+ int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
+ void *p_vrfy )
+{
+ int ret;
+ mbedtls_pk_type_t pk_type;
+ x509_crt_verify_chain_item ver_chain[X509_MAX_VERIFY_CHAIN_SIZE];
+ size_t chain_len;
+ uint32_t *ee_flags = &ver_chain[0].flags;
+
+ *flags = 0;
+ memset( ver_chain, 0, sizeof( ver_chain ) );
+ chain_len = 0;
+
+ if( profile == NULL )
+ {
+ ret = MBEDTLS_ERR_X509_BAD_INPUT_DATA;
+ goto exit;
+ }
+
+ /* check name if requested */
+ if( cn != NULL )
+ x509_crt_verify_name( crt, cn, ee_flags );
+
+ /* Check the type and size of the key */
+ pk_type = mbedtls_pk_get_type( &crt->pk );
+
+ if( x509_profile_check_pk_alg( profile, pk_type ) != 0 )
+ *ee_flags |= MBEDTLS_X509_BADCERT_BAD_PK;
+
+ if( x509_profile_check_key( profile, &crt->pk ) != 0 )
+ *ee_flags |= MBEDTLS_X509_BADCERT_BAD_KEY;
+
+ /* Check the chain */
+ ret = x509_crt_verify_chain( crt, trust_ca, ca_crl, profile,
+ ver_chain, &chain_len );
+ if( ret != 0 )
+ goto exit;
+
+ /* Build final flags, calling callback on the way if any */
+ ret = x509_crt_merge_flags_with_cb( flags,
+ ver_chain, chain_len, f_vrfy, p_vrfy );
+
+exit:
+ /* prevent misuse of the vrfy callback - VERIFY_FAILED would be ignored by
+ * the SSL module for authmode optional, but non-zero return from the
+ * callback means a fatal error so it shouldn't be ignored */
+ if( ret == MBEDTLS_ERR_X509_CERT_VERIFY_FAILED )
+ ret = MBEDTLS_ERR_X509_FATAL_ERROR;
+
+ if( ret != 0 )
+ {
+ *flags = (uint32_t) -1;
+ return( ret );
+ }
+
+ if( *flags != 0 )
+ return( MBEDTLS_ERR_X509_CERT_VERIFY_FAILED );
+
+ return( 0 );
+}
+
+/*
+ * Initialize a certificate chain
+ */
+void mbedtls_x509_crt_init( mbedtls_x509_crt *crt )
+{
+ memset( crt, 0, sizeof(mbedtls_x509_crt) );
+}
+
+/*
+ * Unallocate all certificate data
+ */
+void mbedtls_x509_crt_free( mbedtls_x509_crt *crt )
+{
+ mbedtls_x509_crt *cert_cur = crt;
+ mbedtls_x509_crt *cert_prv;
+ mbedtls_x509_name *name_cur;
+ mbedtls_x509_name *name_prv;
+ mbedtls_x509_sequence *seq_cur;
+ mbedtls_x509_sequence *seq_prv;
+
+ if( crt == NULL )
+ return;
+
+ do
+ {
+ mbedtls_pk_free( &cert_cur->pk );
+
+#if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
+ mbedtls_free( cert_cur->sig_opts );
+#endif
+
+ name_cur = cert_cur->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 );
+ }
+
+ name_cur = cert_cur->subject.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 );
+ }
+
+ seq_cur = cert_cur->ext_key_usage.next;
+ while( seq_cur != NULL )
+ {
+ seq_prv = seq_cur;
+ seq_cur = seq_cur->next;
+ mbedtls_platform_zeroize( seq_prv,
+ sizeof( mbedtls_x509_sequence ) );
+ mbedtls_free( seq_prv );
+ }
+
+ seq_cur = cert_cur->subject_alt_names.next;
+ while( seq_cur != NULL )
+ {
+ seq_prv = seq_cur;
+ seq_cur = seq_cur->next;
+ mbedtls_platform_zeroize( seq_prv,
+ sizeof( mbedtls_x509_sequence ) );
+ mbedtls_free( seq_prv );
+ }
+
+ if( cert_cur->raw.p != NULL )
+ {
+ mbedtls_platform_zeroize( cert_cur->raw.p, cert_cur->raw.len );
+ mbedtls_free( cert_cur->raw.p );
+ }
+
+ cert_cur = cert_cur->next;
+ }
+ while( cert_cur != NULL );
+
+ cert_cur = crt;
+ do
+ {
+ cert_prv = cert_cur;
+ cert_cur = cert_cur->next;
+
+ mbedtls_platform_zeroize( cert_prv, sizeof( mbedtls_x509_crt ) );
+ if( cert_prv != crt )
+ mbedtls_free( cert_prv );
+ }
+ while( cert_cur != NULL );
+}
+
+#endif /* MBEDTLS_X509_CRT_PARSE_C */
projects / proxmark3-svn / blobdiff