Simon Cooksey
Pinned to some recent date
Diff: features/mbedtls/src/x509_csr.c
- Revision:
- 0:fb7af294d5d9
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/features/mbedtls/src/x509_csr.c Thu Nov 17 16:43:53 2016 +0000
@@ -0,0 +1,423 @@
+/*
+ * X.509 Certificate Signing Request (CSR) parsing
+ *
+ * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * This file is part of mbed TLS (https://tls.mbed.org)
+ */
+/*
+ * 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
+ */
+
+#if !defined(MBEDTLS_CONFIG_FILE)
+#include "mbedtls/config.h"
+#else
+#include MBEDTLS_CONFIG_FILE
+#endif
+
+#if defined(MBEDTLS_X509_CSR_PARSE_C)
+
+#include "mbedtls/x509_csr.h"
+#include "mbedtls/oid.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>
+#include <stdio.h>
+#define mbedtls_free free
+#define mbedtls_calloc calloc
+#define mbedtls_snprintf snprintf
+#endif
+
+#if defined(MBEDTLS_FS_IO) || defined(EFIX64) || defined(EFI32)
+#include <stdio.h>
+#endif
+
+/* Implementation that should never be optimized out by the compiler */
+static void mbedtls_zeroize( void *v, size_t n ) {
+ volatile unsigned char *p = v; while( n-- ) *p++ = 0;
+}
+
+/*
+ * Version ::= INTEGER { v1(0) }
+ */
+static int x509_csr_get_version( unsigned char **p,
+ const unsigned char *end,
+ int *ver )
+{
+ int ret;
+
+ if( ( ret = mbedtls_asn1_get_int( p, end, ver ) ) != 0 )
+ {
+ if( ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
+ {
+ *ver = 0;
+ return( 0 );
+ }
+
+ return( MBEDTLS_ERR_X509_INVALID_VERSION + ret );
+ }
+
+ return( 0 );
+}
+
+/*
+ * Parse a CSR in DER format
+ */
+int mbedtls_x509_csr_parse_der( mbedtls_x509_csr *csr,
+ const unsigned char *buf, size_t buflen )
+{
+ int ret;
+ size_t len;
+ unsigned char *p, *end;
+ mbedtls_x509_buf sig_params;
+
+ memset( &sig_params, 0, sizeof( mbedtls_x509_buf ) );
+
+ /*
+ * Check for valid input
+ */
+ if( csr == NULL || buf == NULL || buflen == 0 )
+ return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
+
+ mbedtls_x509_csr_init( csr );
+
+ /*
+ * first copy the raw DER data
+ */
+ p = mbedtls_calloc( 1, len = buflen );
+
+ if( p == NULL )
+ return( MBEDTLS_ERR_X509_ALLOC_FAILED );
+
+ memcpy( p, buf, buflen );
+
+ csr->raw.p = p;
+ csr->raw.len = len;
+ end = p + len;
+
+ /*
+ * CertificationRequest ::= SEQUENCE {
+ * certificationRequestInfo CertificationRequestInfo,
+ * signatureAlgorithm AlgorithmIdentifier,
+ * signature BIT STRING
+ * }
+ */
+ if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
+ MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
+ {
+ mbedtls_x509_csr_free( csr );
+ return( MBEDTLS_ERR_X509_INVALID_FORMAT );
+ }
+
+ if( len != (size_t) ( end - p ) )
+ {
+ mbedtls_x509_csr_free( csr );
+ return( MBEDTLS_ERR_X509_INVALID_FORMAT +
+ MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
+ }
+
+ /*
+ * CertificationRequestInfo ::= SEQUENCE {
+ */
+ csr->cri.p = p;
+
+ if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
+ MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
+ {
+ mbedtls_x509_csr_free( csr );
+ return( MBEDTLS_ERR_X509_INVALID_FORMAT + ret );
+ }
+
+ end = p + len;
+ csr->cri.len = end - csr->cri.p;
+
+ /*
+ * Version ::= INTEGER { v1(0) }
+ */
+ if( ( ret = x509_csr_get_version( &p, end, &csr->version ) ) != 0 )
+ {
+ mbedtls_x509_csr_free( csr );
+ return( ret );
+ }
+
+ csr->version++;
+
+ if( csr->version != 1 )
+ {
+ mbedtls_x509_csr_free( csr );
+ return( MBEDTLS_ERR_X509_UNKNOWN_VERSION );
+ }
+
+ /*
+ * subject Name
+ */
+ csr->subject_raw.p = p;
+
+ if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
+ MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
+ {
+ mbedtls_x509_csr_free( csr );
+ return( MBEDTLS_ERR_X509_INVALID_FORMAT + ret );
+ }
+
+ if( ( ret = mbedtls_x509_get_name( &p, p + len, &csr->subject ) ) != 0 )
+ {
+ mbedtls_x509_csr_free( csr );
+ return( ret );
+ }
+
+ csr->subject_raw.len = p - csr->subject_raw.p;
+
+ /*
+ * subjectPKInfo SubjectPublicKeyInfo
+ */
+ if( ( ret = mbedtls_pk_parse_subpubkey( &p, end, &csr->pk ) ) != 0 )
+ {
+ mbedtls_x509_csr_free( csr );
+ return( ret );
+ }
+
+ /*
+ * attributes [0] Attributes
+ *
+ * The list of possible attributes is open-ended, though RFC 2985
+ * (PKCS#9) defines a few in section 5.4. We currently don't support any,
+ * so we just ignore them. This is a safe thing to do as the worst thing
+ * that could happen is that we issue a certificate that does not match
+ * the requester's expectations - this cannot cause a violation of our
+ * signature policies.
+ */
+ if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
+ MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_CONTEXT_SPECIFIC ) ) != 0 )
+ {
+ mbedtls_x509_csr_free( csr );
+ return( MBEDTLS_ERR_X509_INVALID_FORMAT + ret );
+ }
+
+ p += len;
+
+ end = csr->raw.p + csr->raw.len;
+
+ /*
+ * signatureAlgorithm AlgorithmIdentifier,
+ * signature BIT STRING
+ */
+ if( ( ret = mbedtls_x509_get_alg( &p, end, &csr->sig_oid, &sig_params ) ) != 0 )
+ {
+ mbedtls_x509_csr_free( csr );
+ return( ret );
+ }
+
+ if( ( ret = mbedtls_x509_get_sig_alg( &csr->sig_oid, &sig_params,
+ &csr->sig_md, &csr->sig_pk,
+ &csr->sig_opts ) ) != 0 )
+ {
+ mbedtls_x509_csr_free( csr );
+ return( MBEDTLS_ERR_X509_UNKNOWN_SIG_ALG );
+ }
+
+ if( ( ret = mbedtls_x509_get_sig( &p, end, &csr->sig ) ) != 0 )
+ {
+ mbedtls_x509_csr_free( csr );
+ return( ret );
+ }
+
+ if( p != end )
+ {
+ mbedtls_x509_csr_free( csr );
+ return( MBEDTLS_ERR_X509_INVALID_FORMAT +
+ MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
+ }
+
+ return( 0 );
+}
+
+/*
+ * Parse a CSR, allowing for PEM or raw DER encoding
+ */
+int mbedtls_x509_csr_parse( mbedtls_x509_csr *csr, const unsigned char *buf, size_t buflen )
+{
+ int ret;
+#if defined(MBEDTLS_PEM_PARSE_C)
+ size_t use_len;
+ mbedtls_pem_context pem;
+#endif
+
+ /*
+ * Check for valid input
+ */
+ if( csr == NULL || buf == NULL || buflen == 0 )
+ return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
+
+#if defined(MBEDTLS_PEM_PARSE_C)
+ mbedtls_pem_init( &pem );
+
+ /* Avoid calling mbedtls_pem_read_buffer() on non-null-terminated string */
+ if( buf[buflen - 1] != '\0' )
+ ret = MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT;
+ else
+ ret = mbedtls_pem_read_buffer( &pem,
+ "-----BEGIN CERTIFICATE REQUEST-----",
+ "-----END CERTIFICATE REQUEST-----",
+ buf, NULL, 0, &use_len );
+
+ if( ret == 0 )
+ {
+ /*
+ * Was PEM encoded, parse the result
+ */
+ if( ( ret = mbedtls_x509_csr_parse_der( csr, pem.buf, pem.buflen ) ) != 0 )
+ return( ret );
+
+ mbedtls_pem_free( &pem );
+ return( 0 );
+ }
+ else if( ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT )
+ {
+ mbedtls_pem_free( &pem );
+ return( ret );
+ }
+ else
+#endif /* MBEDTLS_PEM_PARSE_C */
+ return( mbedtls_x509_csr_parse_der( csr, buf, buflen ) );
+}
+
+#if defined(MBEDTLS_FS_IO)
+/*
+ * Load a CSR into the structure
+ */
+int mbedtls_x509_csr_parse_file( mbedtls_x509_csr *csr, 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_csr_parse( csr, buf, n );
+
+ mbedtls_zeroize( buf, n );
+ mbedtls_free( buf );
+
+ return( ret );
+}
+#endif /* MBEDTLS_FS_IO */
+
+#define BEFORE_COLON 14
+#define BC "14"
+/*
+ * Return an informational string about the CSR.
+ */
+int mbedtls_x509_csr_info( char *buf, size_t size, const char *prefix,
+ const mbedtls_x509_csr *csr )
+{
+ int ret;
+ size_t n;
+ char *p;
+ char key_size_str[BEFORE_COLON];
+
+ p = buf;
+ n = size;
+
+ ret = mbedtls_snprintf( p, n, "%sCSR version : %d",
+ prefix, csr->version );
+ MBEDTLS_X509_SAFE_SNPRINTF;
+
+ ret = mbedtls_snprintf( p, n, "\n%ssubject name : ", prefix );
+ MBEDTLS_X509_SAFE_SNPRINTF;
+ ret = mbedtls_x509_dn_gets( p, n, &csr->subject );
+ 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, &csr->sig_oid, csr->sig_pk, csr->sig_md,
+ csr->sig_opts );
+ MBEDTLS_X509_SAFE_SNPRINTF;
+
+ if( ( ret = mbedtls_x509_key_size_helper( key_size_str, BEFORE_COLON,
+ mbedtls_pk_get_name( &csr->pk ) ) ) != 0 )
+ {
+ return( ret );
+ }
+
+ ret = mbedtls_snprintf( p, n, "\n%s%-" BC "s: %d bits\n", prefix, key_size_str,
+ (int) mbedtls_pk_get_bitlen( &csr->pk ) );
+ MBEDTLS_X509_SAFE_SNPRINTF;
+
+ return( (int) ( size - n ) );
+}
+
+/*
+ * Initialize a CSR
+ */
+void mbedtls_x509_csr_init( mbedtls_x509_csr *csr )
+{
+ memset( csr, 0, sizeof(mbedtls_x509_csr) );
+}
+
+/*
+ * Unallocate all CSR data
+ */
+void mbedtls_x509_csr_free( mbedtls_x509_csr *csr )
+{
+ mbedtls_x509_name *name_cur;
+ mbedtls_x509_name *name_prv;
+
+ if( csr == NULL )
+ return;
+
+ mbedtls_pk_free( &csr->pk );
+
+#if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
+ mbedtls_free( csr->sig_opts );
+#endif
+
+ name_cur = csr->subject.next;
+ while( name_cur != NULL )
+ {
+ name_prv = name_cur;
+ name_cur = name_cur->next;
+ mbedtls_zeroize( name_prv, sizeof( mbedtls_x509_name ) );
+ mbedtls_free( name_prv );
+ }
+
+ if( csr->raw.p != NULL )
+ {
+ mbedtls_zeroize( csr->raw.p, csr->raw.len );
+ mbedtls_free( csr->raw.p );
+ }
+
+ mbedtls_zeroize( csr, sizeof( mbedtls_x509_csr ) );
+}
+
+#endif /* MBEDTLS_X509_CSR_PARSE_C */