381 lines
10 KiB
C
381 lines
10 KiB
C
/*
|
|
* 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 "config.h"
|
|
#else
|
|
#include MBEDTLS_CONFIG_FILE
|
|
#endif
|
|
|
|
#if defined(MBEDTLS_ASN1_WRITE_C)
|
|
|
|
#include "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 */
|