| /* |
| * X.509 Certificate Signing Request (CSR) parsing |
| * |
| * Copyright The Mbed TLS Contributors |
| * 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. |
| */ |
| /* |
| * 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 |
| */ |
| |
| #include "common.h" |
| |
| #if defined(MBEDTLS_X509_CSR_PARSE_C) |
| |
| #include "mbedtls/x509_csr.h" |
| #include "mbedtls/error.h" |
| #include "mbedtls/oid.h" |
| #include "mbedtls/platform_util.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 |
| |
| /* |
| * Version ::= INTEGER { v1(0) } |
| */ |
| static int x509_csr_get_version( unsigned char **p, |
| const unsigned char *end, |
| int *ver ) |
| { |
| int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; |
| |
| if( ( ret = mbedtls_asn1_get_int( p, end, ver ) ) != 0 ) |
| { |
| if( ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG ) |
| { |
| *ver = 0; |
| return( 0 ); |
| } |
| |
| return( MBEDTLS_ERROR_ADD( 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 = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; |
| 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_ERROR_ADD( 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_ERROR_ADD( 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 ); |
| } |
| |
| if( csr->version != 0 ) |
| { |
| mbedtls_x509_csr_free( csr ); |
| return( MBEDTLS_ERR_X509_UNKNOWN_VERSION ); |
| } |
| |
| csr->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_ERROR_ADD( 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_ERROR_ADD( 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_ERROR_ADD( 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 ) |
| { |
| #if defined(MBEDTLS_PEM_PARSE_C) |
| int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; |
| 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) |
| /* Avoid calling mbedtls_pem_read_buffer() on non-null-terminated string */ |
| if( buf[buflen - 1] == '\0' ) |
| { |
| mbedtls_pem_init( &pem ); |
| ret = mbedtls_pem_read_buffer( &pem, |
| "-----BEGIN CERTIFICATE REQUEST-----", |
| "-----END CERTIFICATE REQUEST-----", |
| buf, NULL, 0, &use_len ); |
| if( ret == MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT ) |
| { |
| ret = mbedtls_pem_read_buffer( &pem, |
| "-----BEGIN NEW CERTIFICATE REQUEST-----", |
| "-----END NEW CERTIFICATE REQUEST-----", |
| buf, NULL, 0, &use_len ); |
| } |
| |
| if( ret == 0 ) |
| { |
| /* |
| * Was PEM encoded, parse the result |
| */ |
| ret = mbedtls_x509_csr_parse_der( csr, pem.buf, pem.buflen ); |
| } |
| |
| mbedtls_pem_free( &pem ); |
| if( ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT ) |
| return( ret ); |
| } |
| #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 = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; |
| 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_platform_zeroize( buf, n ); |
| mbedtls_free( buf ); |
| |
| return( ret ); |
| } |
| #endif /* MBEDTLS_FS_IO */ |
| |
| #if !defined(MBEDTLS_X509_REMOVE_INFO) |
| #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 = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; |
| 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 ) ); |
| } |
| #endif /* MBEDTLS_X509_REMOVE_INFO */ |
| |
| /* |
| * 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_platform_zeroize( name_prv, sizeof( mbedtls_x509_name ) ); |
| mbedtls_free( name_prv ); |
| } |
| |
| if( csr->raw.p != NULL ) |
| { |
| mbedtls_platform_zeroize( csr->raw.p, csr->raw.len ); |
| mbedtls_free( csr->raw.p ); |
| } |
| |
| mbedtls_platform_zeroize( csr, sizeof( mbedtls_x509_csr ) ); |
| } |
| |
| #endif /* MBEDTLS_X509_CSR_PARSE_C */ |
