yuzu/mbedtls
1
0
Fork 0
mirror of https://github.com/yuzu-emu/mbedtls.git synced 2024-12-25 19:15:35 +00:00
Code Issues Packages Projects Releases Wiki Activity
mbedtls/library/asn1write.c
Paul Bakker c7d6bd4b5f Add mbedtls_asn1_write_len() support for 3 and 4 byte lengths 
As a consequence also adds coverage for reading 3 and 4 byte lengths
(which were not covered before)
2016-08-25 15:42:27 +01:00

391 lines
11 KiB
C
Raw Blame History

/*
* ASN.1 buffer writing functionality
*
* 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)
*/
#if !defined(MBEDTLS_CONFIG_FILE)
#include "mbedtls/config.h"
#else
#include MBEDTLS_CONFIG_FILE
#endif
#if defined(MBEDTLS_ASN1_WRITE_C)
#include "mbedtls/asn1write.h"
#include <string.h>
#if defined(MBEDTLS_PLATFORM_C)
#include "mbedtls/platform.h"
#else
#include <stdlib.h>
#define mbedtls_calloc calloc
#define mbedtls_free free
#endif
int mbedtls_asn1_write_len( unsigned char **p, unsigned char *start, size_t len )
{
if( len < 0x80 )
{
if( *p - start < 1 )
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL );
*--(*p) = (unsigned char) len;
return( 1 );
}
if( len <= 0xFF )
{
if( *p - start < 2 )
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL );
*--(*p) = (unsigned char) len;
*--(*p) = 0x81;
return( 2 );
}
if( len <= 0xFFFF )
{
if( *p - start < 3 )
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL );
*--(*p) = ( len ) & 0xFF;
*--(*p) = ( len >> 8 ) & 0xFF;
*--(*p) = 0x82;
return( 3 );
}
if( len <= 0xFFFFFF )
{
if( *p - start < 4 )
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL );
*--(*p) = ( len ) & 0xFF;
*--(*p) = ( len >> 8 ) & 0xFF;
*--(*p) = ( len >> 16 ) & 0xFF;
*--(*p) = 0x83;
return( 4 );
}
if( len <= 0xFFFFFFFF )
{
if( *p - start < 5 )
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL );
*--(*p) = ( len ) & 0xFF;
*--(*p) = ( len >> 8 ) & 0xFF;
*--(*p) = ( len >> 16 ) & 0xFF;
*--(*p) = ( len >> 24 ) & 0xFF;
*--(*p) = 0x84;
return( 5 );
}
return( MBEDTLS_ERR_ASN1_INVALID_LENGTH );
}
int mbedtls_asn1_write_tag( unsigned char **p, unsigned char *start, unsigned char tag )
{
if( *p - start < 1 )
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL );
*--(*p) = tag;
return( 1 );
}
int mbedtls_asn1_write_raw_buffer( unsigned char **p, unsigned char *start,
const unsigned char *buf, size_t size )
{
size_t len = 0;
if( *p < start || (size_t)( *p - start ) < size )
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL );
len = size;
(*p) -= len;
memcpy( *p, buf, len );
return( (int) len );
}
#if defined(MBEDTLS_BIGNUM_C)
int mbedtls_asn1_write_mpi( unsigned char **p, unsigned char *start, const mbedtls_mpi *X )
{
int ret;
size_t len = 0;
// Write the MPI
//
len = mbedtls_mpi_size( X );
if( *p < start || (size_t)( *p - start ) < len )
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL );
(*p) -= len;
MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( X, *p, len ) );
// DER format assumes 2s complement for numbers, so the leftmost bit
// should be 0 for positive numbers and 1 for negative numbers.
//
if( X->s ==1 && **p & 0x80 )
{
if( *p - start < 1 )
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL );
*--(*p) = 0x00;
len += 1;
}
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, len ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start, MBEDTLS_ASN1_INTEGER ) );
ret = (int) len;
cleanup:
return( ret );
}
#endif /* MBEDTLS_BIGNUM_C */
int mbedtls_asn1_write_null( unsigned char **p, unsigned char *start )
{
int ret;
size_t len = 0;
// Write NULL
//
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, 0) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start, MBEDTLS_ASN1_NULL ) );
return( (int) len );
}
int mbedtls_asn1_write_oid( unsigned char **p, unsigned char *start,
const char *oid, size_t oid_len )
{
int ret;
size_t len = 0;
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_raw_buffer( p, start,
(const unsigned char *) oid, oid_len ) );
MBEDTLS_ASN1_CHK_ADD( len , mbedtls_asn1_write_len( p, start, len ) );
MBEDTLS_ASN1_CHK_ADD( len , mbedtls_asn1_write_tag( p, start, MBEDTLS_ASN1_OID ) );
return( (int) len );
}
int mbedtls_asn1_write_algorithm_identifier( unsigned char **p, unsigned char *start,
const char *oid, size_t oid_len,
size_t par_len )
{
int ret;
size_t len = 0;
if( par_len == 0 )
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_null( p, start ) );
else
len += par_len;
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_oid( p, start, oid, oid_len ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, len ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start,
MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) );
return( (int) len );
}
int mbedtls_asn1_write_bool( unsigned char **p, unsigned char *start, int boolean )
{
int ret;
size_t len = 0;
if( *p - start < 1 )
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL );
*--(*p) = (boolean) ? 255 : 0;
len++;
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, len ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start, MBEDTLS_ASN1_BOOLEAN ) );
return( (int) len );
}
int mbedtls_asn1_write_int( unsigned char **p, unsigned char *start, int val )
{
int ret;
size_t len = 0;
// TODO negative values and values larger than 128
// DER format assumes 2s complement for numbers, so the leftmost bit
// should be 0 for positive numbers and 1 for negative numbers.
//
if( *p - start < 1 )
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL );
len += 1;
*--(*p) = val;
if( val > 0 && **p & 0x80 )
{
if( *p - start < 1 )
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL );
*--(*p) = 0x00;
len += 1;
}
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, len ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start, MBEDTLS_ASN1_INTEGER ) );
return( (int) len );
}
int mbedtls_asn1_write_printable_string( unsigned char **p, unsigned char *start,
const char *text, size_t text_len )
{
int ret;
size_t len = 0;
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_raw_buffer( p, start,
(const unsigned char *) text, text_len ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, len ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start, MBEDTLS_ASN1_PRINTABLE_STRING ) );
return( (int) len );
}
int mbedtls_asn1_write_ia5_string( unsigned char **p, unsigned char *start,
const char *text, size_t text_len )
{
int ret;
size_t len = 0;
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_raw_buffer( p, start,
(const unsigned char *) text, text_len ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, len ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start, MBEDTLS_ASN1_IA5_STRING ) );
return( (int) len );
}
int mbedtls_asn1_write_bitstring( unsigned char **p, unsigned char *start,
const unsigned char *buf, size_t bits )
{
int ret;
size_t len = 0, size;
size = ( bits / 8 ) + ( ( bits % 8 ) ? 1 : 0 );
// Calculate byte length
//
if( *p < start || (size_t)( *p - start ) < size + 1 )
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL );
len = size + 1;
(*p) -= size;
memcpy( *p, buf, size );
// Write unused bits
//
*--(*p) = (unsigned char) (size * 8 - bits);
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, len ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start, MBEDTLS_ASN1_BIT_STRING ) );
return( (int) len );
}
int mbedtls_asn1_write_octet_string( unsigned char **p, unsigned char *start,
const unsigned char *buf, size_t size )
{
int ret;
size_t len = 0;
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_raw_buffer( p, start, buf, size ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, len ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start, MBEDTLS_ASN1_OCTET_STRING ) );
return( (int) len );
}
mbedtls_asn1_named_data *mbedtls_asn1_store_named_data( mbedtls_asn1_named_data **head,
const char *oid, size_t oid_len,
const unsigned char *val,
size_t val_len )
{
mbedtls_asn1_named_data *cur;
if( ( cur = mbedtls_asn1_find_named_data( *head, oid, oid_len ) ) == NULL )
{
// Add new entry if not present yet based on OID
//
cur = (mbedtls_asn1_named_data*)mbedtls_calloc( 1,
sizeof(mbedtls_asn1_named_data) );
if( cur == NULL )
return( NULL );
cur->oid.len = oid_len;
cur->oid.p = mbedtls_calloc( 1, oid_len );
if( cur->oid.p == NULL )
{
mbedtls_free( cur );
return( NULL );
}
memcpy( cur->oid.p, oid, oid_len );
cur->val.len = val_len;
cur->val.p = mbedtls_calloc( 1, val_len );
if( cur->val.p == NULL )
{
mbedtls_free( cur->oid.p );
mbedtls_free( cur );
return( NULL );
}
cur->next = *head;
*head = cur;
}
else if( cur->val.len < val_len )
{
/*
* Enlarge existing value buffer if needed
* Preserve old data until the allocation succeeded, to leave list in
* a consistent state in case allocation fails.
*/
void *p = mbedtls_calloc( 1, val_len );
if( p == NULL )
return( NULL );
mbedtls_free( cur->val.p );
cur->val.p = p;
cur->val.len = val_len;
}
if( val != NULL )
memcpy( cur->val.p, val, val_len );
return( cur );
}
#endif /* MBEDTLS_ASN1_WRITE_C */
Reference in a new issue View git blame Copy permalink