X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/39cc1c879e3d75b3cafd79e4e139a7f6673dd349..700d8687944db0a48535f818b59b6c9859952c61:/common/mbedtls/x509_crt.c diff --git a/common/mbedtls/x509_crt.c b/common/mbedtls/x509_crt.c new file mode 100644 index 00000000..925bddf1 --- /dev/null +++ b/common/mbedtls/x509_crt.c @@ -0,0 +1,2488 @@ +/* + * 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 +#include + +#if defined(MBEDTLS_PEM_PARSE_C) +#include "mbedtls/pem.h" +#endif + +#if defined(MBEDTLS_PLATFORM_C) +#include "mbedtls/platform.h" +#else +#include +#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 +#else +#include +#endif + +#if defined(MBEDTLS_FS_IO) +#include +#if !defined(_WIN32) || defined(EFIX64) || defined(EFI32) +#include +#include +#include +#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 */