/*
* X.509 certificate and private key decoding
*
* Based on XySSL: Copyright (C) 2006-2008 Christophe Devine
*
* Copyright (C) 2009 Paul Bakker <polarssl_maintainer at polarssl dot org>
*
* 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 certificat format for PKI.
*
* http://www.ietf.org/rfc/rfc2459.txt
* http://www.ietf.org/rfc/rfc3279.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_PARSE_C)
#include "polarssl/x509.h"
#include "polarssl/base64.h"
#include "polarssl/des.h"
#include "polarssl/md2.h"
#include "polarssl/md4.h"
#include "polarssl/md5.h"
#include "polarssl/sha1.h"
#include "polarssl/sha2.h"
#include "polarssl/sha4.h"
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include <time.h>
/*
* ASN.1 DER decoding routines
*/
static int asn1_get_len( unsigned char **p,
unsigned char *end,
int *len )
{
if( ( end - *p ) < 1 )
return( POLARSSL_ERR_ASN1_OUT_OF_DATA );
if( ( **p & 0x80 ) == 0 )
*len = *(*p)++;
else
{
switch( **p & 0x7F )
{
case 1:
if( ( end - *p ) < 2 )
return( POLARSSL_ERR_ASN1_OUT_OF_DATA );
*len = (*p)[1];
(*p) += 2;
break;
case 2:
if( ( end - *p ) < 3 )
return( POLARSSL_ERR_ASN1_OUT_OF_DATA );
*len = ( (*p)[1] << 8 ) | (*p)[2];
(*p) += 3;
break;
default:
return( POLARSSL_ERR_ASN1_INVALID_LENGTH );
break;
}
}
if( *len > (int) ( end - *p ) )
return( POLARSSL_ERR_ASN1_OUT_OF_DATA );
return( 0 );
}
static int asn1_get_tag( unsigned char **p,
unsigned char *end,
int *len, int tag )
{
if( ( end - *p ) < 1 )
return( POLARSSL_ERR_ASN1_OUT_OF_DATA );
if( **p != tag )
return( POLARSSL_ERR_ASN1_UNEXPECTED_TAG );
(*p)++;
return( asn1_get_len( p, end, len ) );
}
static int asn1_get_bool( unsigned char **p,
unsigned char *end,
int *val )
{
int ret, len;
if( ( ret = asn1_get_tag( p, end, &len, ASN1_BOOLEAN ) ) != 0 )
return( ret );
if( len != 1 )
return( POLARSSL_ERR_ASN1_INVALID_LENGTH );
*val = ( **p != 0 ) ? 1 : 0;
(*p)++;
return( 0 );
}
static int asn1_get_int( unsigned char **p,
unsigned char *end,
int *val )
{
int ret, len;
if( ( ret = asn1_get_tag( p, end, &len, ASN1_INTEGER ) ) != 0 )
return( ret );
if( len > (int) sizeof( int ) || ( **p & 0x80 ) != 0 )
return( POLARSSL_ERR_ASN1_INVALID_LENGTH );
*val = 0;
while( len-- > 0 )
{
*val = ( *val << 8 ) | **p;
(*p)++;
}
return( 0 );
}
static int asn1_get_mpi( unsigned char **p,
unsigned char *end,
mpi *X )
{
int ret, len;
if( ( ret = asn1_get_tag( p, end, &len, ASN1_INTEGER ) ) != 0 )
return( ret );
ret = mpi_read_binary( X, *p, len );
*p += len;
return( ret );
}
/*
* Version ::= INTEGER { v1(0), v2(1), v3(2) }
*/
static int x509_get_version( unsigned char **p,
unsigned char *end,
int *ver )
{
int ret, len;
if( ( ret = asn1_get_tag( p, end, &len,
ASN1_CONTEXT_SPECIFIC | ASN1_CONSTRUCTED | 0 ) ) != 0 )
{
if( ret == POLARSSL_ERR_ASN1_UNEXPECTED_TAG )
return( *ver = 0 );
return( ret );
}
end = *p + len;
if( ( ret = asn1_get_int( p, end, ver ) ) != 0 )
return( POLARSSL_ERR_X509_CERT_INVALID_VERSION | ret );
if( *p != end )
return( POLARSSL_ERR_X509_CERT_INVALID_VERSION |
POLARSSL_ERR_ASN1_LENGTH_MISMATCH );
return( 0 );
}
/*
* CertificateSerialNumber ::= INTEGER
*/
static int x509_get_serial( unsigned char **p,
unsigned char *end,
x509_buf *serial )
{
int ret;
if( ( end - *p ) < 1 )
return( POLARSSL_ERR_X509_CERT_INVALID_SERIAL |
POLARSSL_ERR_ASN1_OUT_OF_DATA );
if( **p != ( ASN1_CONTEXT_SPECIFIC | ASN1_PRIMITIVE | 2 ) &&
**p != ASN1_INTEGER )
return( POLARSSL_ERR_X509_CERT_INVALID_SERIAL |
POLARSSL_ERR_ASN1_UNEXPECTED_TAG );
serial->tag = *(*p)++;
if( ( ret = asn1_get_len( p, end, &serial->len ) ) != 0 )
return( POLARSSL_ERR_X509_CERT_INVALID_SERIAL | ret );
serial->p = *p;
*p += serial->len;
return( 0 );
}
/*
* AlgorithmIdentifier ::= SEQUENCE {
* algorithm OBJECT IDENTIFIER,
* parameters ANY DEFINED BY algorithm OPTIONAL }
*/
static int x509_get_alg( unsigned char **p,
unsigned char *end,
x509_buf *alg )
{
int ret, len;
if( ( ret = asn1_get_tag( p, end, &len,
ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 )
return( POLARSSL_ERR_X509_CERT_INVALID_ALG | ret );
end = *p + len;
alg->tag = **p;
if( ( ret = asn1_get_tag( p, end, &alg->len, ASN1_OID ) ) != 0 )
return( POLARSSL_ERR_X509_CERT_INVALID_ALG | ret );
alg->p = *p;
*p += alg->len;
if( *p == end )
return( 0 );
/*
* assume the algorithm parameters must be NULL
*/
if( ( ret = asn1_get_tag( p, end, &len, ASN1_NULL ) ) != 0 )
return( POLARSSL_ERR_X509_CERT_INVALID_ALG | ret );
if( *p != end )
return( POLARSSL_ERR_X509_CERT_INVALID_ALG |
POLARSSL_ERR_ASN1_LENGTH_MISMATCH );
return( 0 );
}
/*
* RelativeDistinguishedName ::=
* SET OF AttributeTypeAndValue
*
* AttributeTypeAndValue ::= SEQUENCE {
* type AttributeType,
* value AttributeValue }
*
* AttributeType ::= OBJECT IDENTIFIER
*
* AttributeValue ::= ANY DEFINED BY AttributeType
*/
static int x509_get_name( unsigned char **p,
unsigned char *end,
x509_name *cur )
{
int ret, len;
unsigned char *end2;
x509_buf *oid;
x509_buf *val;
if( ( ret = asn1_get_tag( p, end, &len,
ASN1_CONSTRUCTED | ASN1_SET ) ) != 0 )
return( POLARSSL_ERR_X509_CERT_INVALID_NAME | ret );
end2 = end;
end = *p + len;
if( ( ret = asn1_get_tag( p, end, &len,
ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 )
return( POLARSSL_ERR_X509_CERT_INVALID_NAME | ret );
if( *p + len != end )
return( POLARSSL_ERR_X509_CERT_INVALID_NAME |
POLARSSL_ERR_ASN1_LENGTH_MISMATCH );
oid = &cur->oid;
oid->tag = **p;
if( ( ret = asn1_get_tag( p, end, &oid->len, ASN1_OID ) ) != 0 )
return( POLARSSL_ERR_X509_CERT_INVALID_NAME | ret );
oid->p = *p;
*p += oid->len;
if( ( end - *p ) < 1 )
return( POLARSSL_ERR_X509_CERT_INVALID_NAME |
POLARSSL_ERR_ASN1_OUT_OF_DATA );
if( **p != ASN1_BMP_STRING && **p != ASN1_UTF8_STRING &&
**p != ASN1_T61_STRING && **p != ASN1_PRINTABLE_STRING &&
**p != ASN1_IA5_STRING && **p != ASN1_UNIVERSAL_STRING )
return( POLARSSL_ERR_X509_CERT_INVALID_NAME |
POLARSSL_ERR_ASN1_UNEXPECTED_TAG );
val = &cur->val;
val->tag = *(*p)++;
if( ( ret = asn1_get_len( p, end, &val->len ) ) != 0 )
return( POLARSSL_ERR_X509_CERT_INVALID_NAME | ret );
val->p = *p;
*p += val->len;
cur->next = NULL;
if( *p != end )
return( POLARSSL_ERR_X509_CERT_INVALID_NAME |
POLARSSL_ERR_ASN1_LENGTH_MISMATCH );
/*
* recurse until end of SEQUENCE is reached
*/
if( *p == end2 )
return( 0 );
cur->next = (x509_name *) malloc(
sizeof( x509_name ) );
if( cur->next == NULL )
return( 1 );
return( x509_get_name( p, end2, cur->next ) );
}
/*
* Time ::= CHOICE {
* utcTime UTCTime,
* generalTime GeneralizedTime }
*/
static int x509_get_UTCTime( unsigned char **p,
unsigned char *end,
x509_time *time )
{
int ret, len;
char date[64];
if( ( ret = asn1_get_tag( p, end, &len, ASN1_UTC_TIME ) ) != 0 )
return( POLARSSL_ERR_X509_CERT_INVALID_DATE | ret );
memset( date, 0, sizeof( date ) );
memcpy( date, *p, ( len < (int) sizeof( date ) - 1 ) ?
len : (int) sizeof( date ) - 1 );
if( sscanf( date, "%2d%2d%2d%2d%2d%2d",
&time->year, &time->mon, &time->day,
&time->hour, &time->min, &time->sec ) < 5 )
return( POLARSSL_ERR_X509_CERT_INVALID_DATE );
time->year += 100 * ( time->year < 90 );
time->year += 1900;
*p += len;
return( 0 );
}
/*
* Validity ::= SEQUENCE {
* notBefore Time,
* notAfter Time }
*/
static int x509_get_dates( unsigned char **p,
unsigned char *end,
x509_time *from,
x509_time *to )
{
int ret, len;
if( ( ret = asn1_get_tag( p, end, &len,
ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 )
return( POLARSSL_ERR_X509_CERT_INVALID_DATE | ret );
end = *p + len;
/*
* TODO: also handle GeneralizedTime
*/
if( ( ret = x509_get_UTCTime( p, end, from ) ) != 0 )
return( ret );
if( ( ret = x509_get_UTCTime( p, end, to ) ) != 0 )
return( ret );
if( *p != end )
return( POLARSSL_ERR_X509_CERT_INVALID_DATE |
POLARSSL_ERR_ASN1_LENGTH_MISMATCH );
return( 0 );
}
/*
* SubjectPublicKeyInfo ::= SEQUENCE {
* algorithm AlgorithmIdentifier,
* subjectPublicKey BIT STRING }
*/
static int x509_get_pubkey( unsigned char **p,
unsigned char *end,
x509_buf *pk_alg_oid,
mpi *N, mpi *E )
{
int ret, len;
unsigned char *end2;
if( ( ret = x509_get_alg( p, end, pk_alg_oid ) ) != 0 )
return( ret );
/*
* only RSA public keys handled at this time
*/
if( pk_alg_oid->len != 9 ||
memcmp( pk_alg_oid->p, OID_PKCS1_RSA, 9 ) != 0 )
return( POLARSSL_ERR_X509_CERT_UNKNOWN_PK_ALG );
if( ( ret = asn1_get_tag( p, end, &len, ASN1_BIT_STRING ) ) != 0 )
return( POLARSSL_ERR_X509_CERT_INVALID_PUBKEY | ret );
if( ( end - *p ) < 1 )
return( POLARSSL_ERR_X509_CERT_INVALID_PUBKEY |
POLARSSL_ERR_ASN1_OUT_OF_DATA );
end2 = *p + len;
if( *(*p)++ != 0 )
return( POLARSSL_ERR_X509_CERT_INVALID_PUBKEY );
/*
* RSAPublicKey ::= SEQUENCE {
* modulus INTEGER, -- n
* publicExponent INTEGER -- e
* }
*/
if( ( ret = asn1_get_tag( p, end2, &len,
ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 )
return( POLARSSL_ERR_X509_CERT_INVALID_PUBKEY | ret );
if( *p + len != end2 )
return( POLARSSL_ERR_X509_CERT_INVALID_PUBKEY |
POLARSSL_ERR_ASN1_LENGTH_MISMATCH );
if( ( ret = asn1_get_mpi( p, end2, N ) ) != 0 ||
( ret = asn1_get_mpi( p, end2, E ) ) != 0 )
return( POLARSSL_ERR_X509_CERT_INVALID_PUBKEY | ret );
if( *p != end )
return( POLARSSL_ERR_X509_CERT_INVALID_PUBKEY |
POLARSSL_ERR_ASN1_LENGTH_MISMATCH );
return( 0 );
}
static int x509_get_sig( unsigned char **p,
unsigned char *end,
x509_buf *sig )
{
int ret, len;
sig->tag = **p;
if( ( ret = asn1_get_tag( p, end, &len, ASN1_BIT_STRING ) ) != 0 )
return( POLARSSL_ERR_X509_CERT_INVALID_SIGNATURE | ret );
if( --len < 1 || *(*p)++ != 0 )
return( POLARSSL_ERR_X509_CERT_INVALID_SIGNATURE );
sig->len = len;
sig->p = *p;
*p += len;
return( 0 );
}
/*
* X.509 v2/v3 unique identifier (not parsed)
*/
static int x509_get_uid( unsigned char **p,
unsigned char *end,
x509_buf *uid, int n )
{
int ret;
if( *p == end )
return( 0 );
uid->tag = **p;
if( ( ret = asn1_get_tag( p, end, &uid->len,
ASN1_CONTEXT_SPECIFIC | ASN1_CONSTRUCTED | n ) ) != 0 )
{
if( ret == POLARSSL_ERR_ASN1_UNEXPECTED_TAG )
return( 0 );
return( ret );
}
uid->p = *p;
*p += uid->len;
return( 0 );
}
/*
* X.509 Extensions (No parsing of extensions, pointer should
* be either manually updated or extensions should be parsed!
*/
static int x509_get_ext( unsigned char **p,
unsigned char *end,
x509_buf *ext )
{
int ret, len;
if( *p == end )
return( 0 );
ext->tag = **p;
if( ( ret = asn1_get_tag( p, end, &ext->len,
ASN1_CONTEXT_SPECIFIC | ASN1_CONSTRUCTED | 3 ) ) != 0 )
return( ret );
ext->p = *p;
end = *p + ext->len;
/*
* Extensions ::= SEQUENCE SIZE (1..MAX) OF Extension
*
* Extension ::= SEQUENCE {
* extnID OBJECT IDENTIFIER,
* critical BOOLEAN DEFAULT FALSE,
* extnValue OCTET STRING }
*/
if( ( ret = asn1_get_tag( p, end, &len,
ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 )
return( POLARSSL_ERR_X509_CERT_INVALID_EXTENSIONS | ret );
if( end != *p + len )
return( POLARSSL_ERR_X509_CERT_INVALID_EXTENSIONS |
POLARSSL_ERR_ASN1_LENGTH_MISMATCH );
return( 0 );
}
/*
* X.509 CRL v2 extensions (no extensions parsed yet.)
*/
static int x509_get_crl_ext( unsigned char **p,
unsigned char *end,
x509_buf *ext )
{
int ret, len;
if( ( ret = x509_get_ext( p, end, ext ) ) != 0 )
{
if( ret == POLARSSL_ERR_ASN1_UNEXPECTED_TAG )
return( 0 );
return( ret );
}
while( *p < end )
{
if( ( ret = asn1_get_tag( p, end, &len,
ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 )
return( POLARSSL_ERR_X509_CERT_INVALID_EXTENSIONS | ret );
*p += len;
}
if( *p != end )
return( POLARSSL_ERR_X509_CERT_INVALID_EXTENSIONS |
POLARSSL_ERR_ASN1_LENGTH_MISMATCH );
return( 0 );
}
/*
* X.509 v3 extensions (only BasicConstraints are parsed)
*/
static int x509_get_crt_ext( unsigned char **p,
unsigned char *end,
x509_buf *ext,
int *ca_istrue,
int *max_pathlen )
{
int ret, len;
int is_critical = 1;
int is_cacert = 0;
unsigned char *end2;
if( ( ret = x509_get_ext( p, end, ext ) ) != 0 )
{
if( ret == POLARSSL_ERR_ASN1_UNEXPECTED_TAG )
return( 0 );
return( ret );
}
while( *p < end )
{
if( ( ret = asn1_get_tag( p, end, &len,
ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 )
return( POLARSSL_ERR_X509_CERT_INVALID_EXTENSIONS | ret );
if( memcmp( *p, "\x06\x03\x55\x1D\x13", 5 ) != 0 )
{
*p += len;
continue;
}
*p += 5;
if( ( ret = asn1_get_bool( p, end, &is_critical ) ) != 0 &&
( ret != POLARSSL_ERR_ASN1_UNEXPECTED_TAG ) )
return( POLARSSL_ERR_X509_CERT_INVALID_EXTENSIONS | ret );
if( ( ret = asn1_get_tag( p, end, &len,
ASN1_OCTET_STRING ) ) != 0 )
return( POLARSSL_ERR_X509_CERT_INVALID_EXTENSIONS | ret );
/*
* BasicConstraints ::= SEQUENCE {
* cA BOOLEAN DEFAULT FALSE,
* pathLenConstraint INTEGER (0..MAX) OPTIONAL }
*/
end2 = *p + len;
if( ( ret = asn1_get_tag( p, end2, &len,
ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 )
return( POLARSSL_ERR_X509_CERT_INVALID_EXTENSIONS | ret );
if( *p == end2 )
continue;
if( ( ret = asn1_get_bool( p, end2, &is_cacert ) ) != 0 )
{
if( ret == POLARSSL_ERR_ASN1_UNEXPECTED_TAG )
ret = asn1_get_int( p, end2, &is_cacert );
if( ret != 0 )
return( POLARSSL_ERR_X509_CERT_INVALID_EXTENSIONS | ret );
if( is_cacert != 0 )
is_cacert = 1;
}
if( *p == end2 )
continue;
if( ( ret = asn1_get_int( p, end2, max_pathlen ) ) != 0 )
return( POLARSSL_ERR_X509_CERT_INVALID_EXTENSIONS | ret );
if( *p != end2 )
return( POLARSSL_ERR_X509_CERT_INVALID_EXTENSIONS |
POLARSSL_ERR_ASN1_LENGTH_MISMATCH );
max_pathlen++;
}
if( *p != end )
return( POLARSSL_ERR_X509_CERT_INVALID_EXTENSIONS |
POLARSSL_ERR_ASN1_LENGTH_MISMATCH );
*ca_istrue = is_critical & is_cacert;
return( 0 );
}
/*
* X.509 CRL Entries
*/
static int x509_get_entries( unsigned char **p,
unsigned char *end,
x509_crl_entry *entry )
{
int ret;
x509_crl_entry *cur_entry = entry;
if( *p == end )
return( 0 );
entry->raw.tag = **p;
if( ( ret = asn1_get_tag( p, end, &entry->raw.len,
ASN1_SEQUENCE | ASN1_CONSTRUCTED ) ) != 0 )
{
if( ret == POLARSSL_ERR_ASN1_UNEXPECTED_TAG )
return( 0 );
return( ret );
}
entry->raw.p = *p;
end = *p + entry->raw.len;
while( *p < end )
{
int len2;
if( ( ret = asn1_get_tag( p, end, &len2,
ASN1_SEQUENCE | ASN1_CONSTRUCTED ) ) != 0 )
{
if( ret == POLARSSL_ERR_ASN1_UNEXPECTED_TAG )
return( 0 );
return( ret );
}
if( ( ret = x509_get_serial( p, end, &cur_entry->serial ) ) != 0 )
return( ret );
if( ( ret = x509_get_UTCTime( p, end, &cur_entry->revocation_date ) ) != 0 )
return( ret );
if( ( ret = x509_get_crl_ext( p, end, &cur_entry->entry_ext ) ) != 0 )
return( ret );
if ( *p < end ) {
cur_entry->next = malloc( sizeof( x509_crl_entry ) );
cur_entry = cur_entry->next;
memset( cur_entry, 0, sizeof( x509_crl_entry ) );
}
}
return( 0 );
}
/*
* Parse one or more certificates and add them to the chained list
*/
int x509parse_crt( x509_cert *chain, unsigned char *buf, int buflen )
{
int ret, len;
unsigned char *s1, *s2;
unsigned char *p, *end;
x509_cert *crt;
crt = chain;
/*
* Check for valid input
*/
if( crt == NULL || buf == NULL )
return( 1 );
while( crt->version != 0 && crt->next != NULL )
crt = crt->next;
/*
* Add new certificate on the end of the chain if needed.
*/
if ( crt->version != 0 && crt->next == NULL)
{
crt->next = (x509_cert *) malloc( sizeof( x509_cert ) );
if( crt->next == NULL )
{
x509_free( crt );
return( 1 );
}
crt = crt->next;
memset( crt, 0, sizeof( x509_cert ) );
}
/*
* check if the certificate is encoded in base64
*/
s1 = (unsigned char *) strstr( (char *) buf,
"-----BEGIN CERTIFICATE-----" );
if( s1 != NULL )
{
s2 = (unsigned char *) strstr( (char *) buf,
"-----END CERTIFICATE-----" );
if( s2 == NULL || s2 <= s1 )
return( POLARSSL_ERR_X509_CERT_INVALID_PEM );
s1 += 27;
if( *s1 == '\r' ) s1++;
if( *s1 == '\n' ) s1++;
else return( POLARSSL_ERR_X509_CERT_INVALID_PEM );
/*
* get the DER data length and decode the buffer
*/
len = 0;
ret = base64_decode( NULL, &len, s1, s2 - s1 );
if( ret == POLARSSL_ERR_BASE64_INVALID_CHARACTER )
return( POLARSSL_ERR_X509_CERT_INVALID_PEM | ret );
if( ( p = (unsigned char *) malloc( len ) ) == NULL )
return( 1 );
if( ( ret = base64_decode( p, &len, s1, s2 - s1 ) ) != 0 )
{
free( p );
return( POLARSSL_ERR_X509_CERT_INVALID_PEM | ret );
}
/*
* update the buffer size and offset
*/
s2 += 25;
if( *s2 == '\r' ) s2++;
if( *s2 == '\n' ) s2++;
else
{
free( p );
return( POLARSSL_ERR_X509_CERT_INVALID_PEM );
}
buflen -= s2 - buf;
buf = s2;
}
else
{
/*
* nope, copy the raw DER data
*/
p = (unsigned char *) malloc( len = buflen );
if( p == NULL )
return( 1 );
memcpy( p, buf, buflen );
buflen = 0;
}
crt->raw.p = p;
crt->raw.len = len;
end = p + len;
/*
* Certificate ::= SEQUENCE {
* tbsCertificate TBSCertificate,
* signatureAlgorithm AlgorithmIdentifier,
* signatureValue BIT STRING }
*/
if( ( ret = asn1_get_tag( &p, end, &len,
ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 )
{
x509_free( crt );
return( POLARSSL_ERR_X509_CERT_INVALID_FORMAT );
}
if( len != (int) ( end - p ) )
{
x509_free( crt );
return( POLARSSL_ERR_X509_CERT_INVALID_FORMAT |
POLARSSL_ERR_ASN1_LENGTH_MISMATCH );
}
/*
* TBSCertificate ::= SEQUENCE {
*/
crt->tbs.p = p;
if( ( ret = asn1_get_tag( &p, end, &len,
ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 )
{
x509_free( crt );
return( POLARSSL_ERR_X509_CERT_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 = x509_get_serial( &p, end, &crt->serial ) ) != 0 ||
( ret = x509_get_alg( &p, end, &crt->sig_oid1 ) ) != 0 )
{
x509_free( crt );
return( ret );
}
crt->version++;
if( crt->version > 3 )
{
x509_free( crt );
return( POLARSSL_ERR_X509_CERT_UNKNOWN_VERSION );
}
if( crt->sig_oid1.len != 9 ||
memcmp( crt->sig_oid1.p, OID_PKCS1, 8 ) != 0 )
{
x509_free( crt );
return( POLARSSL_ERR_X509_CERT_UNKNOWN_SIG_ALG );
}
if( crt->sig_oid1.p[8] < 2 ||
( crt->sig_oid1.p[8] > 5 && crt->sig_oid1.p[8] < 11 ) ||
crt->sig_oid1.p[8] > 14 )
{
x509_free( crt );
return( POLARSSL_ERR_X509_CERT_UNKNOWN_SIG_ALG );
}
/*
* issuer Name
*/
crt->issuer_raw.p = p;
if( ( ret = asn1_get_tag( &p, end, &len,
ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 )
{
x509_free( crt );
return( POLARSSL_ERR_X509_CERT_INVALID_FORMAT | ret );
}
if( ( ret = x509_get_name( &p, p + len, &crt->issuer ) ) != 0 )
{
x509_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 )
{
x509_free( crt );
return( ret );
}
/*
* subject Name
*/
crt->subject_raw.p = p;
if( ( ret = asn1_get_tag( &p, end, &len,
ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 )
{
x509_free( crt );
return( POLARSSL_ERR_X509_CERT_INVALID_FORMAT | ret );
}
if( ( ret = x509_get_name( &p, p + len, &crt->subject ) ) != 0 )
{
x509_free( crt );
return( ret );
}
crt->subject_raw.len = p - crt->subject_raw.p;
/*
* SubjectPublicKeyInfo ::= SEQUENCE
* algorithm AlgorithmIdentifier,
* subjectPublicKey BIT STRING }
*/
if( ( ret = asn1_get_tag( &p, end, &len,
ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 )
{
x509_free( crt );
return( POLARSSL_ERR_X509_CERT_INVALID_FORMAT | ret );
}
if( ( ret = x509_get_pubkey( &p, p + len, &crt->pk_oid,
&crt->rsa.N, &crt->rsa.E ) ) != 0 )
{
x509_free( crt );
return( ret );
}
if( ( ret = rsa_check_pubkey( &crt->rsa ) ) != 0 )
{
x509_free( crt );
return( ret );
}
crt->rsa.len = mpi_size( &crt->rsa.N );
/*
* 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 )
{
x509_free( crt );
return( ret );
}
}
if( crt->version == 2 || crt->version == 3 )
{
ret = x509_get_uid( &p, end, &crt->subject_id, 2 );
if( ret != 0 )
{
x509_free( crt );
return( ret );
}
}
if( crt->version == 3 )
{
ret = x509_get_crt_ext( &p, end, &crt->v3_ext,
&crt->ca_istrue, &crt->max_pathlen );
if( ret != 0 )
{
x509_free( crt );
return( ret );
}
}
if( p != end )
{
x509_free( crt );
return( POLARSSL_ERR_X509_CERT_INVALID_FORMAT |
POLARSSL_ERR_ASN1_LENGTH_MISMATCH );
}
end = crt->raw.p + crt->raw.len;
/*
* signatureAlgorithm AlgorithmIdentifier,
* signatureValue BIT STRING
*/
if( ( ret = x509_get_alg( &p, end, &crt->sig_oid2 ) ) != 0 )
{
x509_free( crt );
return( ret );
}
if( memcmp( crt->sig_oid1.p, crt->sig_oid2.p, crt->sig_oid1.len ) != 0 )
{
x509_free( crt );
return( POLARSSL_ERR_X509_CERT_SIG_MISMATCH );
}
if( ( ret = x509_get_sig( &p, end, &crt->sig ) ) != 0 )
{
x509_free( crt );
return( ret );
}
if( p != end )
{
x509_free( crt );
return( POLARSSL_ERR_X509_CERT_INVALID_FORMAT |
POLARSSL_ERR_ASN1_LENGTH_MISMATCH );
}
if( buflen > 0 )
{
crt->next = (x509_cert *) malloc( sizeof( x509_cert ) );
if( crt->next == NULL )
{
x509_free( crt );
return( 1 );
}
crt = crt->next;
memset( crt, 0, sizeof( x509_cert ) );
return( x509parse_crt( crt, buf, buflen ) );
}
return( 0 );
}
/*
* Parse one or more CRLs and add them to the chained list
*/
int x509parse_crl( x509_crl *chain, unsigned char *buf, int buflen )
{
int ret, len;
unsigned char *s1, *s2;
unsigned char *p, *end;
x509_crl *crl;
crl = chain;
/*
* Check for valid input
*/
if( crl == NULL || buf == NULL )
return( 1 );
while( crl->version != 0 && crl->next != NULL )
crl = crl->next;
/*
* Add new CRL on the end of the chain if needed.
*/
if ( crl->version != 0 && crl->next == NULL)
{
crl->next = (x509_crl *) malloc( sizeof( x509_crl ) );
if( crl->next == NULL )
{
x509_crl_free( crl );
return( 1 );
}
crl = crl->next;
memset( crl, 0, sizeof( x509_crl ) );
}
/*
* check if the CRL is encoded in base64
*/
s1 = (unsigned char *) strstr( (char *) buf,
"-----BEGIN X509 CRL-----" );
if( s1 != NULL )
{
s2 = (unsigned char *) strstr( (char *) buf,
"-----END X509 CRL-----" );
if( s2 == NULL || s2 <= s1 )
return( POLARSSL_ERR_X509_CERT_INVALID_PEM );
s1 += 24;
if( *s1 == '\r' ) s1++;
if( *s1 == '\n' ) s1++;
else return( POLARSSL_ERR_X509_CERT_INVALID_PEM );
/*
* get the DER data length and decode the buffer
*/
len = 0;
ret = base64_decode( NULL, &len, s1, s2 - s1 );
if( ret == POLARSSL_ERR_BASE64_INVALID_CHARACTER )
return( POLARSSL_ERR_X509_CERT_INVALID_PEM | ret );
if( ( p = (unsigned char *) malloc( len ) ) == NULL )
return( 1 );
if( ( ret = base64_decode( p, &len, s1, s2 - s1 ) ) != 0 )
{
free( p );
return( POLARSSL_ERR_X509_CERT_INVALID_PEM | ret );
}
/*
* update the buffer size and offset
*/
s2 += 22;
if( *s2 == '\r' ) s2++;
if( *s2 == '\n' ) s2++;
else
{
free( p );
return( POLARSSL_ERR_X509_CERT_INVALID_PEM );
}
buflen -= s2 - buf;
buf = s2;
}
else
{
/*
* nope, copy the raw DER data
*/
p = (unsigned char *) malloc( len = buflen );
if( p == NULL )
return( 1 );
memcpy( p, buf, buflen );
buflen = 0;
}
crl->raw.p = p;
crl->raw.len = len;
end = p + len;
/*
* CertificateList ::= SEQUENCE {
* tbsCertList TBSCertList,
* signatureAlgorithm AlgorithmIdentifier,
* signatureValue BIT STRING }
*/
if( ( ret = asn1_get_tag( &p, end, &len,
ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 )
{
x509_crl_free( crl );
return( POLARSSL_ERR_X509_CERT_INVALID_FORMAT );
}
if( len != (int) ( end - p ) )
{
x509_crl_free( crl );
return( POLARSSL_ERR_X509_CERT_INVALID_FORMAT |
POLARSSL_ERR_ASN1_LENGTH_MISMATCH );
}
/*
* TBSCertList ::= SEQUENCE {
*/
crl->tbs.p = p;
if( ( ret = asn1_get_tag( &p, end, &len,
ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 )
{
x509_crl_free( crl );
return( POLARSSL_ERR_X509_CERT_INVALID_FORMAT | ret );
}
end = p + len;
crl->tbs.len = end - crl->tbs.p;
/*
* Version ::= INTEGER OPTIONAL { v1(0), v2(1) }
* -- if present, MUST be v2
*
* signature AlgorithmIdentifier
*/
if( ( ret = x509_get_version( &p, end, &crl->version ) ) != 0 ||
( ret = x509_get_alg( &p, end, &crl->sig_oid1 ) ) != 0 )
{
x509_crl_free( crl );
return( ret );
}
crl->version++;
if( crl->version > 2 )
{
x509_crl_free( crl );
return( POLARSSL_ERR_X509_CERT_UNKNOWN_VERSION );
}
if( crl->sig_oid1.len != 9 ||
memcmp( crl->sig_oid1.p, OID_PKCS1, 8 ) != 0 )
{
x509_crl_free( crl );
return( POLARSSL_ERR_X509_CERT_UNKNOWN_SIG_ALG );
}
if( crl->sig_oid1.p[8] < 2 ||
( crl->sig_oid1.p[8] > 5 && crl->sig_oid1.p[8] < 11 ) ||
crl->sig_oid1.p[8] > 14 )
{
x509_crl_free( crl );
return( POLARSSL_ERR_X509_CERT_UNKNOWN_SIG_ALG );
}
/*
* issuer Name
*/
crl->issuer_raw.p = p;
if( ( ret = asn1_get_tag( &p, end, &len,
ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 )
{
x509_crl_free( crl );
return( POLARSSL_ERR_X509_CERT_INVALID_FORMAT | ret );
}
if( ( ret = x509_get_name( &p, p + len, &crl->issuer ) ) != 0 )
{
x509_crl_free( crl );
return( ret );
}
crl->issuer_raw.len = p - crl->issuer_raw.p;
/*
* thisUpdate Time
* nextUpdate Time OPTIONAL
*/
if( ( ret = x509_get_UTCTime( &p, end, &crl->this_update ) ) != 0 )
{
x509_crl_free( crl );
return( ret );
}
if( ( ret = x509_get_UTCTime( &p, end, &crl->next_update ) ) != 0 )
{
if ( ret != POLARSSL_ERR_ASN1_UNEXPECTED_TAG ) {
x509_crl_free( crl );
return( ret );
}
}
/*
* revokedCertificates SEQUENCE OF SEQUENCE {
* userCertificate CertificateSerialNumber,
* revocationDate Time,
* crlEntryExtensions Extensions OPTIONAL
* -- if present, MUST be v2
* } OPTIONAL
*/
if( ( ret = x509_get_entries( &p, end, &crl->entry ) ) != 0 )
{
x509_crl_free( crl );
return( ret );
}
/*
* crlExtensions EXPLICIT Extensions OPTIONAL
* -- if present, MUST be v2
*/
if( crl->version == 2 )
{
ret = x509_get_crl_ext( &p, end, &crl->crl_ext );
if( ret != 0 )
{
x509_crl_free( crl );
return( ret );
}
}
if( p != end )
{
x509_crl_free( crl );
return( POLARSSL_ERR_X509_CERT_INVALID_FORMAT |
POLARSSL_ERR_ASN1_LENGTH_MISMATCH );
}
end = crl->raw.p + crl->raw.len;
/*
* signatureAlgorithm AlgorithmIdentifier,
* signatureValue BIT STRING
*/
if( ( ret = x509_get_alg( &p, end, &crl->sig_oid2 ) ) != 0 )
{
x509_crl_free( crl );
return( ret );
}
if( memcmp( crl->sig_oid1.p, crl->sig_oid2.p, crl->sig_oid1.len ) != 0 )
{
x509_crl_free( crl );
return( POLARSSL_ERR_X509_CERT_SIG_MISMATCH );
}
if( ( ret = x509_get_sig( &p, end, &crl->sig ) ) != 0 )
{
x509_crl_free( crl );
return( ret );
}
if( p != end )
{
x509_crl_free( crl );
return( POLARSSL_ERR_X509_CERT_INVALID_FORMAT |
POLARSSL_ERR_ASN1_LENGTH_MISMATCH );
}
if( buflen > 0 )
{
crl->next = (x509_crl *) malloc( sizeof( x509_crl ) );
if( crl->next == NULL )
{
x509_crl_free( crl );
return( 1 );
}
crl = crl->next;
memset( crl, 0, sizeof( x509_crl ) );
return( x509parse_crl( crl, buf, buflen ) );
}
return( 0 );
}
/*
* Load all data from a file into a given buffer.
*/
int load_file( char *path, unsigned char **buf, size_t *n )
{
FILE *f;
if( ( f = fopen( path, "rb" ) ) == NULL )
return( 1 );
fseek( f, 0, SEEK_END );
*n = (size_t) ftell( f );
fseek( f, 0, SEEK_SET );
if( ( *buf = (unsigned char *) malloc( *n + 1 ) ) == NULL )
return( 1 );
if( fread( *buf, 1, *n, f ) != *n )
{
fclose( f );
free( *buf );
return( 1 );
}
fclose( f );
(*buf)[*n] = '\0';
return( 0 );
}
/*
* Load one or more certificates and add them to the chained list
*/
int x509parse_crtfile( x509_cert *chain, char *path )
{
int ret;
size_t n;
unsigned char *buf;
if ( load_file( path, &buf, &n ) )
return( 1 );
ret = x509parse_crt( chain, buf, (int) n );
memset( buf, 0, n + 1 );
free( buf );
return( ret );
}
/*
* Load one or more CRLs and add them to the chained list
*/
int x509parse_crlfile( x509_crl *chain, char *path )
{
int ret;
size_t n;
unsigned char *buf;
if ( load_file( path, &buf, &n ) )
return( 1 );
ret = x509parse_crl( chain, buf, (int) n );
memset( buf, 0, n + 1 );
free( buf );
return( ret );
}
#if defined(POLARSSL_DES_C)
/*
* Read a 16-byte hex string and convert it to binary
*/
static int x509_get_iv( unsigned char *s, unsigned char iv[8] )
{
int i, j, k;
memset( iv, 0, 8 );
for( i = 0; i < 16; i++, s++ )
{
if( *s >= '0' && *s <= '9' ) j = *s - '0'; else
if( *s >= 'A' && *s <= 'F' ) j = *s - '7'; else
if( *s >= 'a' && *s <= 'f' ) j = *s - 'W'; else
return( POLARSSL_ERR_X509_KEY_INVALID_ENC_IV );
k = ( ( i & 1 ) != 0 ) ? j : j << 4;
iv[i >> 1] = (unsigned char)( iv[i >> 1] | k );
}
return( 0 );
}
/*
* Decrypt with 3DES-CBC, using PBKDF1 for key derivation
*/
static void x509_des3_decrypt( unsigned char des3_iv[8],
unsigned char *buf, int buflen,
unsigned char *pwd, int pwdlen )
{
md5_context md5_ctx;
des3_context des3_ctx;
unsigned char md5sum[16];
unsigned char des3_key[24];
/*
* 3DES key[ 0..15] = MD5(pwd || IV)
* key[16..23] = MD5(pwd || IV || 3DES key[ 0..15])
*/
md5_starts( &md5_ctx );
md5_update( &md5_ctx, pwd, pwdlen );
md5_update( &md5_ctx, des3_iv, 8 );
md5_finish( &md5_ctx, md5sum );
memcpy( des3_key, md5sum, 16 );
md5_starts( &md5_ctx );
md5_update( &md5_ctx, md5sum, 16 );
md5_update( &md5_ctx, pwd, pwdlen );
md5_update( &md5_ctx, des3_iv, 8 );
md5_finish( &md5_ctx, md5sum );
memcpy( des3_key + 16, md5sum, 8 );
des3_set3key_dec( &des3_ctx, des3_key );
des3_crypt_cbc( &des3_ctx, DES_DECRYPT, buflen,
des3_iv, buf, buf );
memset( &md5_ctx, 0, sizeof( md5_ctx ) );
memset( &des3_ctx, 0, sizeof( des3_ctx ) );
memset( md5sum, 0, 16 );
memset( des3_key, 0, 24 );
}
#endif
/*
* Parse a private RSA key
*/
int x509parse_key( rsa_context *rsa, unsigned char *buf, int buflen,
unsigned char *pwd, int pwdlen )
{
int ret, len, enc;
unsigned char *s1, *s2;
unsigned char *p, *end;
unsigned char des3_iv[8];
s1 = (unsigned char *) strstr( (char *) buf,
"-----BEGIN RSA PRIVATE KEY-----" );
if( s1 != NULL )
{
s2 = (unsigned char *) strstr( (char *) buf,
"-----END RSA PRIVATE KEY-----" );
if( s2 == NULL || s2 <= s1 )
return( POLARSSL_ERR_X509_KEY_INVALID_PEM );
s1 += 31;
if( *s1 == '\r' ) s1++;
if( *s1 == '\n' ) s1++;
else return( POLARSSL_ERR_X509_KEY_INVALID_PEM );
enc = 0;
if( memcmp( s1, "Proc-Type: 4,ENCRYPTED", 22 ) == 0 )
{
#if defined(POLARSSL_DES_C)
enc++;
s1 += 22;
if( *s1 == '\r' ) s1++;
if( *s1 == '\n' ) s1++;
else return( POLARSSL_ERR_X509_KEY_INVALID_PEM );
if( memcmp( s1, "DEK-Info: DES-EDE3-CBC,", 23 ) != 0 )
return( POLARSSL_ERR_X509_KEY_UNKNOWN_ENC_ALG );
s1 += 23;
if( x509_get_iv( s1, des3_iv ) != 0 )
return( POLARSSL_ERR_X509_KEY_INVALID_ENC_IV );
s1 += 16;
if( *s1 == '\r' ) s1++;
if( *s1 == '\n' ) s1++;
else return( POLARSSL_ERR_X509_KEY_INVALID_PEM );
#else
return( POLARSSL_ERR_X509_FEATURE_UNAVAILABLE );
#endif
}
len = 0;
ret = base64_decode( NULL, &len, s1, s2 - s1 );
if( ret == POLARSSL_ERR_BASE64_INVALID_CHARACTER )
return( ret | POLARSSL_ERR_X509_KEY_INVALID_PEM );
if( ( buf = (unsigned char *) malloc( len ) ) == NULL )
return( 1 );
if( ( ret = base64_decode( buf, &len, s1, s2 - s1 ) ) != 0 )
{
free( buf );
return( ret | POLARSSL_ERR_X509_KEY_INVALID_PEM );
}
buflen = len;
if( enc != 0 )
{
#if defined(POLARSSL_DES_C)
if( pwd == NULL )
{
free( buf );
return( POLARSSL_ERR_X509_KEY_PASSWORD_REQUIRED );
}
x509_des3_decrypt( des3_iv, buf, buflen, pwd, pwdlen );
if( buf[0] != 0x30 || buf[1] != 0x82 ||
buf[4] != 0x02 || buf[5] != 0x01 )
{
free( buf );
return( POLARSSL_ERR_X509_KEY_PASSWORD_MISMATCH );
}
#else
return( POLARSSL_ERR_X509_FEATURE_UNAVAILABLE );
#endif
}
}
memset( rsa, 0, sizeof( rsa_context ) );
p = buf;
end = buf + buflen;
/*
* RSAPrivateKey ::= SEQUENCE {
* version Version,
* modulus INTEGER, -- n
* publicExponent INTEGER, -- e
* privateExponent INTEGER, -- d
* prime1 INTEGER, -- p
* prime2 INTEGER, -- q
* exponent1 INTEGER, -- d mod (p-1)
* exponent2 INTEGER, -- d mod (q-1)
* coefficient INTEGER, -- (inverse of q) mod p
* otherPrimeInfos OtherPrimeInfos OPTIONAL
* }
*/
if( ( ret = asn1_get_tag( &p, end, &len,
ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 )
{
if( s1 != NULL )
free( buf );
rsa_free( rsa );
return( POLARSSL_ERR_X509_KEY_INVALID_FORMAT | ret );
}
end = p + len;
if( ( ret = asn1_get_int( &p, end, &rsa->ver ) ) != 0 )
{
if( s1 != NULL )
free( buf );
rsa_free( rsa );
return( POLARSSL_ERR_X509_KEY_INVALID_FORMAT | ret );
}
if( rsa->ver != 0 )
{
if( s1 != NULL )
free( buf );
rsa_free( rsa );
return( ret | POLARSSL_ERR_X509_KEY_INVALID_VERSION );
}
if( ( ret = asn1_get_mpi( &p, end, &rsa->N ) ) != 0 ||
( ret = asn1_get_mpi( &p, end, &rsa->E ) ) != 0 ||
( ret = asn1_get_mpi( &p, end, &rsa->D ) ) != 0 ||
( ret = asn1_get_mpi( &p, end, &rsa->P ) ) != 0 ||
( ret = asn1_get_mpi( &p, end, &rsa->Q ) ) != 0 ||
( ret = asn1_get_mpi( &p, end, &rsa->DP ) ) != 0 ||
( ret = asn1_get_mpi( &p, end, &rsa->DQ ) ) != 0 ||
( ret = asn1_get_mpi( &p, end, &rsa->QP ) ) != 0 )
{
if( s1 != NULL )
free( buf );
rsa_free( rsa );
return( ret | POLARSSL_ERR_X509_KEY_INVALID_FORMAT );
}
rsa->len = mpi_size( &rsa->N );
if( p != end )
{
if( s1 != NULL )
free( buf );
rsa_free( rsa );
return( POLARSSL_ERR_X509_KEY_INVALID_FORMAT |
POLARSSL_ERR_ASN1_LENGTH_MISMATCH );
}
if( ( ret = rsa_check_privkey( rsa ) ) != 0 )
{
if( s1 != NULL )
free( buf );
rsa_free( rsa );
return( ret );
}
if( s1 != NULL )
free( buf );
return( 0 );
}
/*
* Load and parse a private RSA key
*/
int x509parse_keyfile( rsa_context *rsa, char *path, char *pwd )
{
int ret;
size_t n;
unsigned char *buf;
if ( load_file( path, &buf, &n ) )
return( 1 );
if( pwd == NULL )
ret = x509parse_key( rsa, buf, (int) n, NULL, 0 );
else
ret = x509parse_key( rsa, buf, (int) n,
(unsigned char *) pwd, strlen( pwd ) );
memset( buf, 0, n + 1 );
free( buf );
return( ret );
}
#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.
*/
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( 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 ( ret > n ) { \
p[n - 1] = '\0'; \
return POLARSSL_ERR_DEBUG_BUF_TOO_SMALL;\
} \
\
n -= ret; \
p += ret; \
}
/*
* Store the name in printable form into buf; no more
* than size characters will be written
*/
int x509parse_dn_gets( char *buf, size_t size, x509_name *dn )
{
int i, ret, n;
unsigned char c;
x509_name *name;
char s[128], *p;
memset( s, 0, sizeof( s ) );
name = dn;
p = buf;
n = size;
while( name != NULL )
{
if( name != dn ) {
ret = snprintf( p, n, ", " );
SAFE_SNPRINTF();
}
if( memcmp( name->oid.p, OID_X520, 2 ) == 0 )
{
switch( name->oid.p[2] )
{
case X520_COMMON_NAME:
ret = snprintf( p, n, "CN=" ); break;
case X520_COUNTRY:
ret = snprintf( p, n, "C=" ); break;
case X520_LOCALITY:
ret = snprintf( p, n, "L=" ); break;
case X520_STATE:
ret = snprintf( p, n, "ST=" ); break;
case X520_ORGANIZATION:
ret = snprintf( p, n, "O=" ); break;
case X520_ORG_UNIT:
ret = snprintf( p, n, "OU=" ); break;
default:
ret = snprintf( p, n, "0x%02X=",
name->oid.p[2] );
break;
}
SAFE_SNPRINTF();
}
else if( memcmp( name->oid.p, OID_PKCS9, 8 ) == 0 )
{
switch( name->oid.p[8] )
{
case PKCS9_EMAIL:
ret = snprintf( p, n, "emailAddress=" ); break;
default:
ret = snprintf( p, n, "0x%02X=",
name->oid.p[8] );
break;
}
SAFE_SNPRINTF();
}
else
{
ret = snprintf( p, n, "\?\?=" );
SAFE_SNPRINTF();
}
for( i = 0; i < name->val.len; i++ )
{
if( i >= (int) sizeof( s ) - 1 )
break;
c = name->val.p[i];
if( c < 32 || c == 127 || ( c > 128 && c < 160 ) )
s[i] = '?';
else s[i] = c;
}
s[i] = '\0';
ret = snprintf( p, n, "%s", s );
SAFE_SNPRINTF();
name = name->next;
}
return( size - n );
}
/*
* Return an informational string about the certificate.
*/
int x509parse_cert_info( char *buf, size_t size, char *prefix, x509_cert *crt )
{
int i, n, nr, ret;
char *p;
p = buf;
n = size;
ret = snprintf( p, n, "%scert. version : %d\n",
prefix, crt->version );
SAFE_SNPRINTF();
ret = snprintf( p, n, "%sserial number : ",
prefix );
SAFE_SNPRINTF();
nr = ( crt->serial.len <= 32 )
? crt->serial.len : 32;
for( i = 0; i < nr; i++ )
{
ret = snprintf( p, n, "%02X%s",
crt->serial.p[i], ( i < nr - 1 ) ? ":" : "" );
SAFE_SNPRINTF();
}
ret = snprintf( p, n, "\n%sissuer name : ", prefix );
SAFE_SNPRINTF();
ret = x509parse_dn_gets( p, n, &crt->issuer );
SAFE_SNPRINTF();
ret = snprintf( p, n, "\n%ssubject name : ", prefix );
SAFE_SNPRINTF();
ret = x509parse_dn_gets( p, n, &crt->subject );
SAFE_SNPRINTF();
ret = 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 );
SAFE_SNPRINTF();
ret = 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 );
SAFE_SNPRINTF();
ret = snprintf( p, n, "\n%ssigned using : RSA+", prefix );
SAFE_SNPRINTF();
switch( crt->sig_oid1.p[8] )
{
case SIG_RSA_MD2 : ret = snprintf( p, n, "MD2" ); break;
case SIG_RSA_MD4 : ret = snprintf( p, n, "MD4" ); break;
case SIG_RSA_MD5 : ret = snprintf( p, n, "MD5" ); break;
case SIG_RSA_SHA1 : ret = snprintf( p, n, "SHA1" ); break;
case SIG_RSA_SHA224 : ret = snprintf( p, n, "SHA224" ); break;
case SIG_RSA_SHA256 : ret = snprintf( p, n, "SHA256" ); break;
case SIG_RSA_SHA384 : ret = snprintf( p, n, "SHA384" ); break;
case SIG_RSA_SHA512 : ret = snprintf( p, n, "SHA512" ); break;
default: ret = snprintf( p, n, "???" ); break;
}
SAFE_SNPRINTF();
ret = snprintf( p, n, "\n%sRSA key size : %d bits\n", prefix,
crt->rsa.N.n * (int) sizeof( unsigned long ) * 8 );
SAFE_SNPRINTF();
return( size - n );
}
/*
* Return an informational string about the CRL.
*/
int x509parse_crl_info( char *buf, size_t size, char *prefix, x509_crl *crl )
{
int i, n, nr, ret;
char *p;
x509_crl_entry *entry;
p = buf;
n = size;
ret = snprintf( p, n, "%sCRL version : %d",
prefix, crl->version );
SAFE_SNPRINTF();
ret = snprintf( p, n, "\n%sissuer name : ", prefix );
SAFE_SNPRINTF();
ret = x509parse_dn_gets( p, n, &crl->issuer );
SAFE_SNPRINTF();
ret = snprintf( p, n, "\n%sthis update : " \
"%04d-%02d-%02d %02d:%02d:%02d", prefix,
crl->this_update.year, crl->this_update.mon,
crl->this_update.day, crl->this_update.hour,
crl->this_update.min, crl->this_update.sec );
SAFE_SNPRINTF();
ret = snprintf( p, n, "\n%snext update : " \
"%04d-%02d-%02d %02d:%02d:%02d", prefix,
crl->next_update.year, crl->next_update.mon,
crl->next_update.day, crl->next_update.hour,
crl->next_update.min, crl->next_update.sec );
SAFE_SNPRINTF();
entry = &crl->entry;
ret = snprintf( p, n, "\n%sRevoked certificates:",
prefix );
SAFE_SNPRINTF();
while( entry != NULL )
{
ret = snprintf( p, n, "\n%sserial number: ",
prefix );
SAFE_SNPRINTF();
nr = ( entry->serial.len <= 32 )
? entry->serial.len : 32;
for( i = 0; i < nr; i++ ) {
ret = snprintf( p, n, "%02X%s",
entry->serial.p[i], ( i < nr - 1 ) ? ":" : "" );
SAFE_SNPRINTF();
}
ret = snprintf( p, n, " revocation date: " \
"%04d-%02d-%02d %02d:%02d:%02d",
entry->revocation_date.year, entry->revocation_date.mon,
entry->revocation_date.day, entry->revocation_date.hour,
entry->revocation_date.min, entry->revocation_date.sec );
SAFE_SNPRINTF();
entry = entry->next;
}
ret = snprintf( p, n, "\n%ssigned using : RSA+", prefix );
SAFE_SNPRINTF();
switch( crl->sig_oid1.p[8] )
{
case SIG_RSA_MD2 : ret = snprintf( p, n, "MD2" ); break;
case SIG_RSA_MD4 : ret = snprintf( p, n, "MD4" ); break;
case SIG_RSA_MD5 : ret = snprintf( p, n, "MD5" ); break;
case SIG_RSA_SHA1 : ret = snprintf( p, n, "SHA1" ); break;
case SIG_RSA_SHA224 : ret = snprintf( p, n, "SHA224" ); break;
case SIG_RSA_SHA256 : ret = snprintf( p, n, "SHA256" ); break;
case SIG_RSA_SHA384 : ret = snprintf( p, n, "SHA384" ); break;
case SIG_RSA_SHA512 : ret = snprintf( p, n, "SHA512" ); break;
default: ret = snprintf( p, n, "???" ); break;
}
SAFE_SNPRINTF();
ret = snprintf( p, n, "\n" );
SAFE_SNPRINTF();
return( size - n );
}
/*
* Return 0 if the x509_time is still valid, or 1 otherwise.
*/
int x509parse_time_expired( x509_time *to )
{
struct tm *lt;
time_t tt;
tt = time( NULL );
lt = localtime( &tt );
if( lt->tm_year > to->year - 1900 )
return( 1 );
if( lt->tm_year == to->year - 1900 &&
lt->tm_mon > to->mon - 1 )
return( 1 );
if( lt->tm_year == to->year - 1900 &&
lt->tm_mon == to->mon - 1 &&
lt->tm_mday > to->day )
return( 1 );
return( 0 );
}
/*
* Return 1 if the certificate is revoked, or 0 otherwise.
*/
int x509parse_revoked( x509_cert *crt, x509_crl *crl )
{
x509_crl_entry *cur = &crl->entry;
while( cur != NULL && cur->serial.len != 0 )
{
if( memcmp( crt->serial.p, cur->serial.p, crt->serial.len ) == 0 )
{
if( x509parse_time_expired( &cur->revocation_date ) )
return( 1 );
}
cur = cur->next;
}
return( 0 );
}
static void x509_hash( unsigned char *in, int len, int alg,
unsigned char *out )
{
switch( alg )
{
#if defined(POLARSSL_MD2_C)
case SIG_RSA_MD2 : md2( in, len, out ); break;
#endif
#if defined(POLARSSL_MD4_C)
case SIG_RSA_MD4 : md4( in, len, out ); break;
#endif
case SIG_RSA_MD5 : md5( in, len, out ); break;
case SIG_RSA_SHA1 : sha1( in, len, out ); break;
#if defined(POLARSSL_SHA2_C)
case SIG_RSA_SHA224 : sha2( in, len, out, 1 ); break;
case SIG_RSA_SHA256 : sha2( in, len, out, 0 ); break;
#endif
#if defined(POLARSSL_SHA2_C)
case SIG_RSA_SHA384 : sha4( in, len, out, 1 ); break;
case SIG_RSA_SHA512 : sha4( in, len, out, 0 ); break;
#endif
default:
memset( out, '\xFF', len );
break;
}
}
/*
* Verify the certificate validity
*/
int x509parse_verify( x509_cert *crt,
x509_cert *trust_ca,
x509_crl *ca_crl,
char *cn, int *flags )
{
int cn_len;
int hash_id;
int pathlen;
x509_cert *cur;
x509_name *name;
unsigned char hash[64];
*flags = 0;
if( x509parse_time_expired( &crt->valid_to ) )
*flags = BADCERT_EXPIRED;
if( cn != NULL )
{
name = &crt->subject;
cn_len = strlen( cn );
while( name != NULL )
{
if( memcmp( name->oid.p, OID_CN, 3 ) == 0 &&
memcmp( name->val.p, cn, cn_len ) == 0 &&
name->val.len == cn_len )
break;
name = name->next;
}
if( name == NULL )
*flags |= BADCERT_CN_MISMATCH;
}
*flags |= BADCERT_NOT_TRUSTED;
/*
* Iterate upwards in the given cert chain,
* ignoring any upper cert with CA != TRUE.
*/
cur = crt->next;
pathlen = 1;
while( cur != NULL && cur->version != 0 )
{
if( cur->ca_istrue == 0 ||
crt->issuer_raw.len != cur->subject_raw.len ||
memcmp( crt->issuer_raw.p, cur->subject_raw.p,
crt->issuer_raw.len ) != 0 )
{
cur = cur->next;
continue;
}
hash_id = crt->sig_oid1.p[8];
x509_hash( crt->tbs.p, crt->tbs.len, hash_id, hash );
if( rsa_pkcs1_verify( &cur->rsa, RSA_PUBLIC, hash_id,
0, hash, crt->sig.p ) != 0 )
return( POLARSSL_ERR_X509_CERT_VERIFY_FAILED );
pathlen++;
crt = cur;
cur = crt->next;
}
/*
* Atempt to validate topmost cert with our CA chain.
*/
while( trust_ca != NULL && trust_ca->version != 0 )
{
if( crt->issuer_raw.len != trust_ca->subject_raw.len ||
memcmp( crt->issuer_raw.p, trust_ca->subject_raw.p,
crt->issuer_raw.len ) != 0 )
{
trust_ca = trust_ca->next;
continue;
}
if( trust_ca->max_pathlen > 0 &&
trust_ca->max_pathlen < pathlen )
break;
hash_id = crt->sig_oid1.p[8];
x509_hash( crt->tbs.p, crt->tbs.len, hash_id, hash );
if( rsa_pkcs1_verify( &trust_ca->rsa, RSA_PUBLIC, hash_id,
0, hash, crt->sig.p ) == 0 )
{
/*
* cert. is signed by a trusted CA
*/
*flags &= ~BADCERT_NOT_TRUSTED;
break;
}
trust_ca = trust_ca->next;
}
/*
* TODO: What happens if no CRL is present?
* Suggestion: Revocation state should be unknown if no CRL is present.
* For backwards compatibility this is not yet implemented.
*/
/*
* Check if the topmost certificate is revoked if the trusted CA is
* determined.
*/
while( trust_ca != NULL && ca_crl != NULL && ca_crl->version != 0 )
{
if( ca_crl->issuer_raw.len != trust_ca->subject_raw.len ||
memcmp( ca_crl->issuer_raw.p, trust_ca->subject_raw.p,
ca_crl->issuer_raw.len ) != 0 )
{
ca_crl = ca_crl->next;
continue;
}
/*
* Check if CRL is correctry signed by the trusted CA
*/
hash_id = ca_crl->sig_oid1.p[8];
x509_hash( ca_crl->tbs.p, ca_crl->tbs.len, hash_id, hash );
if( !rsa_pkcs1_verify( &trust_ca->rsa, RSA_PUBLIC, hash_id,
0, hash, ca_crl->sig.p ) == 0 )
{
/*
* CRL is not trusted
*/
*flags |= BADCRL_NOT_TRUSTED;
break;
}
/*
* Check for validity of CRL (Do not drop out)
*/
if( x509parse_time_expired( &ca_crl->next_update ) )
*flags |= BADCRL_EXPIRED;
/*
* Check if certificate is revoked
*/
if( x509parse_revoked(crt, ca_crl) )
{
*flags |= BADCERT_REVOKED;
break;
}
ca_crl = ca_crl->next;
}
if( *flags != 0 )
return( POLARSSL_ERR_X509_CERT_VERIFY_FAILED );
return( 0 );
}
/*
* Unallocate all certificate data
*/
void x509_free( x509_cert *crt )
{
x509_cert *cert_cur = crt;
x509_cert *cert_prv;
x509_name *name_cur;
x509_name *name_prv;
if( crt == NULL )
return;
do
{
rsa_free( &cert_cur->rsa );
name_cur = cert_cur->issuer.next;
while( name_cur != NULL )
{
name_prv = name_cur;
name_cur = name_cur->next;
memset( name_prv, 0, sizeof( x509_name ) );
free( name_prv );
}
name_cur = cert_cur->subject.next;
while( name_cur != NULL )
{
name_prv = name_cur;
name_cur = name_cur->next;
memset( name_prv, 0, sizeof( x509_name ) );
free( name_prv );
}
if( cert_cur->raw.p != NULL )
{
memset( cert_cur->raw.p, 0, cert_cur->raw.len );
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;
memset( cert_prv, 0, sizeof( x509_cert ) );
if( cert_prv != crt )
free( cert_prv );
}
while( cert_cur != NULL );
}
/*
* Unallocate all CRL data
*/
void x509_crl_free( x509_crl *crl )
{
x509_crl *crl_cur = crl;
x509_crl *crl_prv;
x509_name *name_cur;
x509_name *name_prv;
x509_crl_entry *entry_cur;
x509_crl_entry *entry_prv;
if( crl == NULL )
return;
do
{
name_cur = crl_cur->issuer.next;
while( name_cur != NULL )
{
name_prv = name_cur;
name_cur = name_cur->next;
memset( name_prv, 0, sizeof( x509_name ) );
free( name_prv );
}
entry_cur = crl_cur->entry.next;
while( entry_cur != NULL )
{
entry_prv = entry_cur;
entry_cur = entry_cur->next;
memset( entry_prv, 0, sizeof( x509_crl_entry ) );
free( entry_prv );
}
if( crl_cur->raw.p != NULL )
{
memset( crl_cur->raw.p, 0, crl_cur->raw.len );
free( crl_cur->raw.p );
}
crl_cur = crl_cur->next;
}
while( crl_cur != NULL );
crl_cur = crl;
do
{
crl_prv = crl_cur;
crl_cur = crl_cur->next;
memset( crl_prv, 0, sizeof( x509_crl ) );
if( crl_prv != crl )
free( crl_prv );
}
while( crl_cur != NULL );
}
#if defined(POLARSSL_SELF_TEST)
#include "polarssl/certs.h"
/*
* Checkup routine
*/
int x509_self_test( int verbose )
{
int ret, i, j;
x509_cert cacert;
x509_cert clicert;
rsa_context rsa;
if( verbose != 0 )
printf( " X.509 certificate load: " );
memset( &clicert, 0, sizeof( x509_cert ) );
ret = x509parse_crt( &clicert, (unsigned char *) test_cli_crt,
strlen( test_cli_crt ) );
if( ret != 0 )
{
if( verbose != 0 )
printf( "failed\n" );
return( ret );
}
memset( &cacert, 0, sizeof( x509_cert ) );
ret = x509parse_crt( &cacert, (unsigned char *) test_ca_crt,
strlen( test_ca_crt ) );
if( ret != 0 )
{
if( verbose != 0 )
printf( "failed\n" );
return( ret );
}
if( verbose != 0 )
printf( "passed\n X.509 private key load: " );
i = strlen( test_ca_key );
j = strlen( test_ca_pwd );
if( ( ret = x509parse_key( &rsa,
(unsigned char *) test_ca_key, i,
(unsigned char *) test_ca_pwd, j ) ) != 0 )
{
if( verbose != 0 )
printf( "failed\n" );
return( ret );
}
if( verbose != 0 )
printf( "passed\n X.509 signature verify: ");
ret = x509parse_verify( &clicert, &cacert, NULL, "PolarSSL Client 2", &i );
if( ret != 0 )
{
if( verbose != 0 )
printf( "failed\n" );
return( ret );
}
if( verbose != 0 )
printf( "passed\n\n" );
x509_free( &cacert );
x509_free( &clicert );
rsa_free( &rsa );
return( 0 );
}
#endif
#endif