| /* |
| * X.509 Certificate Signing Request (CSR) parsing |
| * |
| * Copyright (C) 2006-2013, Brainspark B.V. |
| * |
| * This file is part of PolarSSL (http://www.polarssl.org) |
| * Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org> |
| * |
| * All rights reserved. |
| * |
| * 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. |
| */ |
| /* |
| * The ITU-T X.509 standard defines a certificate format for PKI. |
| * |
| * http://www.ietf.org/rfc/rfc3279.txt |
| * http://www.ietf.org/rfc/rfc3280.txt |
| * |
| * ftp://ftp.rsasecurity.com/pub/pkcs/ascii/pkcs-1v2.asc |
| * |
| * 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 "polarssl/config.h" |
| |
| #if defined(POLARSSL_X509_CSR_PARSE_C) |
| |
| #include "polarssl/x509_csr.h" |
| #include "polarssl/oid.h" |
| #if defined(POLARSSL_PEM_PARSE_C) |
| #include "polarssl/pem.h" |
| #endif |
| |
| #if defined(POLARSSL_MEMORY_C) |
| #include "polarssl/memory.h" |
| #else |
| #define polarssl_malloc malloc |
| #define polarssl_free free |
| #endif |
| |
| #include <string.h> |
| #include <stdlib.h> |
| |
| #if defined(POLARSSL_FS_IO) |
| #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; |
| |
| if( ( ret = asn1_get_int( p, end, ver ) ) != 0 ) |
| { |
| if( ret == POLARSSL_ERR_ASN1_UNEXPECTED_TAG ) |
| { |
| *ver = 0; |
| return( 0 ); |
| } |
| |
| return( POLARSSL_ERR_X509_INVALID_VERSION + ret ); |
| } |
| |
| return( 0 ); |
| } |
| |
| /* |
| * Parse a CSR |
| */ |
| int x509_csr_parse( x509_csr *csr, const unsigned char *buf, size_t buflen ) |
| { |
| int ret; |
| size_t len; |
| unsigned char *p, *end; |
| #if defined(POLARSSL_PEM_PARSE_C) |
| size_t use_len; |
| pem_context pem; |
| #endif |
| |
| /* |
| * Check for valid input |
| */ |
| if( csr == NULL || buf == NULL ) |
| return( POLARSSL_ERR_X509_BAD_INPUT_DATA ); |
| |
| x509_csr_init( csr ); |
| |
| #if defined(POLARSSL_PEM_PARSE_C) |
| pem_init( &pem ); |
| ret = pem_read_buffer( &pem, |
| "-----BEGIN CERTIFICATE REQUEST-----", |
| "-----END CERTIFICATE REQUEST-----", |
| buf, NULL, 0, &use_len ); |
| |
| if( ret == 0 ) |
| { |
| /* |
| * Was PEM encoded |
| */ |
| buflen -= use_len; |
| buf += use_len; |
| |
| /* |
| * Steal PEM buffer |
| */ |
| p = pem.buf; |
| pem.buf = NULL; |
| len = pem.buflen; |
| pem_free( &pem ); |
| } |
| else if( ret != POLARSSL_ERR_PEM_NO_HEADER_FOOTER_PRESENT ) |
| { |
| pem_free( &pem ); |
| return( ret ); |
| } |
| else |
| #endif |
| { |
| /* |
| * nope, copy the raw DER data |
| */ |
| p = (unsigned char *) polarssl_malloc( len = buflen ); |
| |
| if( p == NULL ) |
| return( POLARSSL_ERR_X509_MALLOC_FAILED ); |
| |
| memcpy( p, buf, buflen ); |
| |
| buflen = 0; |
| } |
| |
| csr->raw.p = p; |
| csr->raw.len = len; |
| end = p + len; |
| |
| /* |
| * CertificationRequest ::= SEQUENCE { |
| * certificationRequestInfo CertificationRequestInfo, |
| * signatureAlgorithm AlgorithmIdentifier, |
| * signature BIT STRING |
| * } |
| */ |
| if( ( ret = asn1_get_tag( &p, end, &len, |
| ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 ) |
| { |
| x509_csr_free( csr ); |
| return( POLARSSL_ERR_X509_INVALID_FORMAT ); |
| } |
| |
| if( len != (size_t) ( end - p ) ) |
| { |
| x509_csr_free( csr ); |
| return( POLARSSL_ERR_X509_INVALID_FORMAT + |
| POLARSSL_ERR_ASN1_LENGTH_MISMATCH ); |
| } |
| |
| /* |
| * CertificationRequestInfo ::= SEQUENCE { |
| */ |
| csr->cri.p = p; |
| |
| if( ( ret = asn1_get_tag( &p, end, &len, |
| ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 ) |
| { |
| x509_csr_free( csr ); |
| return( POLARSSL_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 ) |
| { |
| x509_csr_free( csr ); |
| return( ret ); |
| } |
| |
| csr->version++; |
| |
| if( csr->version != 1 ) |
| { |
| x509_csr_free( csr ); |
| return( POLARSSL_ERR_X509_UNKNOWN_VERSION ); |
| } |
| |
| /* |
| * subject Name |
| */ |
| csr->subject_raw.p = p; |
| |
| if( ( ret = asn1_get_tag( &p, end, &len, |
| ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 ) |
| { |
| x509_csr_free( csr ); |
| return( POLARSSL_ERR_X509_INVALID_FORMAT + ret ); |
| } |
| |
| if( ( ret = x509_get_name( &p, p + len, &csr->subject ) ) != 0 ) |
| { |
| x509_csr_free( csr ); |
| return( ret ); |
| } |
| |
| csr->subject_raw.len = p - csr->subject_raw.p; |
| |
| /* |
| * subjectPKInfo SubjectPublicKeyInfo |
| */ |
| if( ( ret = pk_parse_subpubkey( &p, end, &csr->pk ) ) != 0 ) |
| { |
| x509_csr_free( csr ); |
| return( ret ); |
| } |
| |
| /* |
| * attributes [0] Attributes |
| */ |
| if( ( ret = asn1_get_tag( &p, end, &len, |
| ASN1_CONSTRUCTED | ASN1_CONTEXT_SPECIFIC ) ) != 0 ) |
| { |
| x509_csr_free( csr ); |
| return( POLARSSL_ERR_X509_INVALID_FORMAT + ret ); |
| } |
| // TODO Parse Attributes / extension requests |
| |
| p += len; |
| |
| end = csr->raw.p + csr->raw.len; |
| |
| /* |
| * signatureAlgorithm AlgorithmIdentifier, |
| * signature BIT STRING |
| */ |
| if( ( ret = x509_get_alg_null( &p, end, &csr->sig_oid ) ) != 0 ) |
| { |
| x509_csr_free( csr ); |
| return( ret ); |
| } |
| |
| if( ( ret = x509_get_sig_alg( &csr->sig_oid, &csr->sig_md, |
| &csr->sig_pk ) ) != 0 ) |
| { |
| x509_csr_free( csr ); |
| return( POLARSSL_ERR_X509_UNKNOWN_SIG_ALG ); |
| } |
| |
| if( ( ret = x509_get_sig( &p, end, &csr->sig ) ) != 0 ) |
| { |
| x509_csr_free( csr ); |
| return( ret ); |
| } |
| |
| if( p != end ) |
| { |
| x509_csr_free( csr ); |
| return( POLARSSL_ERR_X509_INVALID_FORMAT + |
| POLARSSL_ERR_ASN1_LENGTH_MISMATCH ); |
| } |
| |
| return( 0 ); |
| } |
| |
| #if defined(POLARSSL_FS_IO) |
| /* |
| * Load a CSR into the structure |
| */ |
| int x509_csr_parse_file( x509_csr *csr, const char *path ) |
| { |
| int ret; |
| size_t n; |
| unsigned char *buf; |
| |
| if ( ( ret = x509_load_file( path, &buf, &n ) ) != 0 ) |
| return( ret ); |
| |
| ret = x509_csr_parse( csr, buf, n ); |
| |
| memset( buf, 0, n + 1 ); |
| polarssl_free( buf ); |
| |
| return( ret ); |
| } |
| #endif /* POLARSSL_FS_IO */ |
| |
| #if defined _MSC_VER && !defined snprintf |
| #include <stdarg.h> |
| |
| #if !defined vsnprintf |
| #define vsnprintf _vsnprintf |
| #endif // vsnprintf |
| |
| /* |
| * Windows _snprintf and _vsnprintf are not compatible to linux versions. |
| * Result value is not size of buffer needed, but -1 if no fit is possible. |
| * |
| * This fuction tries to 'fix' this by at least suggesting enlarging the |
| * size by 20. |
| */ |
| static int compat_snprintf(char *str, size_t size, const char *format, ...) |
| { |
| va_list ap; |
| int res = -1; |
| |
| va_start( ap, format ); |
| |
| res = vsnprintf( str, size, format, ap ); |
| |
| va_end( ap ); |
| |
| // No quick fix possible |
| if ( res < 0 ) |
| return( (int) size + 20 ); |
| |
| return res; |
| } |
| |
| #define snprintf compat_snprintf |
| #endif |
| |
| #define POLARSSL_ERR_DEBUG_BUF_TOO_SMALL -2 |
| |
| #define SAFE_SNPRINTF() \ |
| { \ |
| if( ret == -1 ) \ |
| return( -1 ); \ |
| \ |
| if ( (unsigned int) ret > n ) { \ |
| p[n - 1] = '\0'; \ |
| return POLARSSL_ERR_DEBUG_BUF_TOO_SMALL;\ |
| } \ |
| \ |
| n -= (unsigned int) ret; \ |
| p += (unsigned int) ret; \ |
| } |
| |
| #define BEFORE_COLON 14 |
| #define BC "14" |
| /* |
| * Return an informational string about the CSR. |
| */ |
| int x509_csr_info( char *buf, size_t size, const char *prefix, |
| const x509_csr *csr ) |
| { |
| int ret; |
| size_t n; |
| char *p; |
| const char *desc; |
| char key_size_str[BEFORE_COLON]; |
| |
| p = buf; |
| n = size; |
| |
| ret = snprintf( p, n, "%sCSR version : %d", |
| prefix, csr->version ); |
| SAFE_SNPRINTF(); |
| |
| ret = snprintf( p, n, "\n%ssubject name : ", prefix ); |
| SAFE_SNPRINTF(); |
| ret = x509_dn_gets( p, n, &csr->subject ); |
| SAFE_SNPRINTF(); |
| |
| ret = snprintf( p, n, "\n%ssigned using : ", prefix ); |
| SAFE_SNPRINTF(); |
| |
| ret = oid_get_sig_alg_desc( &csr->sig_oid, &desc ); |
| if( ret != 0 ) |
| ret = snprintf( p, n, "???" ); |
| else |
| ret = snprintf( p, n, "%s", desc ); |
| SAFE_SNPRINTF(); |
| |
| if( ( ret = x509_key_size_helper( key_size_str, BEFORE_COLON, |
| pk_get_name( &csr->pk ) ) ) != 0 ) |
| { |
| return( ret ); |
| } |
| |
| ret = snprintf( p, n, "\n%s%-" BC "s: %d bits\n", prefix, key_size_str, |
| (int) pk_get_size( &csr->pk ) ); |
| SAFE_SNPRINTF(); |
| |
| return( (int) ( size - n ) ); |
| } |
| |
| /* |
| * Initialize a CSR |
| */ |
| void x509_csr_init( x509_csr *csr ) |
| { |
| memset( csr, 0, sizeof(x509_csr) ); |
| } |
| |
| /* |
| * Unallocate all CSR data |
| */ |
| void x509_csr_free( x509_csr *csr ) |
| { |
| x509_name *name_cur; |
| x509_name *name_prv; |
| |
| if( csr == NULL ) |
| return; |
| |
| pk_free( &csr->pk ); |
| |
| name_cur = csr->subject.next; |
| while( name_cur != NULL ) |
| { |
| name_prv = name_cur; |
| name_cur = name_cur->next; |
| memset( name_prv, 0, sizeof( x509_name ) ); |
| polarssl_free( name_prv ); |
| } |
| |
| if( csr->raw.p != NULL ) |
| { |
| memset( csr->raw.p, 0, csr->raw.len ); |
| polarssl_free( csr->raw.p ); |
| } |
| |
| memset( csr, 0, sizeof( x509_csr ) ); |
| } |
| |
| #endif /* POLARSSL_X509_CSR_PARSE_C */ |