luckfox-pico-sdk/media/security/librkcrypto/test/c_mode/asn1parse.c

/*
 *  Generic ASN.1 parsing
 *
 *  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_PARSE_C)

#include "asn1.h"

#include <string.h>

#if defined(MBEDTLS_BIGNUM_C)
#include "bignum.h"
#endif

#if defined(MBEDTLS_PLATFORM_C)
#include "mbedtls/platform.h"
#else
#include <stdlib.h>
#define mbedtls_calloc calloc
#define mbedtls_free free
#endif

/* Implementation that should never be optimized out by the compiler */
static void mbedtls_zeroize(void *v, size_t n) {
  volatile unsigned char *p = (unsigned char *)v;
  while (n--)
    *p++ = 0;
}

/*
 * ASN.1 DER decoding routines
 */
int mbedtls_asn1_get_len(unsigned char **p, const unsigned char *end,
                         size_t *len) {
  if ((end - *p) < 1)
    return (MBEDTLS_ERR_ASN1_OUT_OF_DATA);

  if ((**p & 0x80) == 0)
    *len = *(*p)++;
  else {
    switch (**p & 0x7F) {
    case 1:
      if ((end - *p) < 2)
        return (MBEDTLS_ERR_ASN1_OUT_OF_DATA);

      *len = (*p)[1];
      (*p) += 2;
      break;

    case 2:
      if ((end - *p) < 3)
        return (MBEDTLS_ERR_ASN1_OUT_OF_DATA);

      *len = ((size_t)(*p)[1] << 8) | (*p)[2];
      (*p) += 3;
      break;

    case 3:
      if ((end - *p) < 4)
        return (MBEDTLS_ERR_ASN1_OUT_OF_DATA);

      *len = ((size_t)(*p)[1] << 16) | ((size_t)(*p)[2] << 8) | (*p)[3];
      (*p) += 4;
      break;

    case 4:
      if ((end - *p) < 5)
        return (MBEDTLS_ERR_ASN1_OUT_OF_DATA);

      *len = ((size_t)(*p)[1] << 24) | ((size_t)(*p)[2] << 16) |
             ((size_t)(*p)[3] << 8) | (*p)[4];
      (*p) += 5;
      break;

    default:
      return (MBEDTLS_ERR_ASN1_INVALID_LENGTH);
    }
  }

  if (*len > (size_t)(end - *p))
    return (MBEDTLS_ERR_ASN1_OUT_OF_DATA);

  return (0);
}

int mbedtls_asn1_get_tag(unsigned char **p, const unsigned char *end,
                         size_t *len, int tag) {
  if ((end - *p) < 1)
    return (MBEDTLS_ERR_ASN1_OUT_OF_DATA);

  if (**p != tag)
    return (MBEDTLS_ERR_ASN1_UNEXPECTED_TAG);

  (*p)++;

  return (mbedtls_asn1_get_len(p, end, len));
}

int mbedtls_asn1_get_bool(unsigned char **p, const unsigned char *end,
                          int *val) {
  int ret;
  size_t len;

  if ((ret = mbedtls_asn1_get_tag(p, end, &len, MBEDTLS_ASN1_BOOLEAN)) != 0)
    return (ret);

  if (len != 1)
    return (MBEDTLS_ERR_ASN1_INVALID_LENGTH);

  *val = (**p != 0) ? 1 : 0;
  (*p)++;

  return (0);
}

int mbedtls_asn1_get_int(unsigned char **p, const unsigned char *end,
                         int *val) {
  int ret;
  size_t len;

  if ((ret = mbedtls_asn1_get_tag(p, end, &len, MBEDTLS_ASN1_INTEGER)) != 0)
    return (ret);

  if (len == 0 || len > sizeof(int) || (**p & 0x80) != 0)
    return (MBEDTLS_ERR_ASN1_INVALID_LENGTH);

  *val = 0;

  while (len-- > 0) {
    *val = (*val << 8) | **p;
    (*p)++;
  }

  return (0);
}

#if defined(MBEDTLS_BIGNUM_C)
int mbedtls_asn1_get_mpi(unsigned char **p, const unsigned char *end,
                         mbedtls_mpi *X) {
  int ret;
  size_t len;

  if ((ret = mbedtls_asn1_get_tag(p, end, &len, MBEDTLS_ASN1_INTEGER)) != 0)
    return (ret);

  ret = mbedtls_mpi_read_binary(X, *p, len);

  *p += len;

  return (ret);
}
#endif /* MBEDTLS_BIGNUM_C */

int mbedtls_asn1_get_bitstring(unsigned char **p, const unsigned char *end,
                               mbedtls_asn1_bitstring *bs) {
  int ret;

  /* Certificate type is a single byte bitstring */
  if ((ret = mbedtls_asn1_get_tag(p, end, &bs->len, MBEDTLS_ASN1_BIT_STRING)) !=
      0)
    return (ret);

  /* Check length, subtract one for actual bit string length */
  if (bs->len < 1)
    return (MBEDTLS_ERR_ASN1_OUT_OF_DATA);
  bs->len -= 1;

  /* Get number of unused bits, ensure unused bits <= 7 */
  bs->unused_bits = **p;
  if (bs->unused_bits > 7)
    return (MBEDTLS_ERR_ASN1_INVALID_LENGTH);
  (*p)++;

  /* Get actual bitstring */
  bs->p = *p;
  *p += bs->len;

  if (*p != end)
    return (MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);

  return (0);
}

/*
 * Get a bit string without unused bits
 */
int mbedtls_asn1_get_bitstring_null(unsigned char **p, const unsigned char *end,
                                    size_t *len) {
  int ret;

  if ((ret = mbedtls_asn1_get_tag(p, end, len, MBEDTLS_ASN1_BIT_STRING)) != 0)
    return (ret);

  if ((*len)-- < 2 || *(*p)++ != 0)
    return (MBEDTLS_ERR_ASN1_INVALID_DATA);

  return (0);
}

/*
 *  Parses and splits an ASN.1 "SEQUENCE OF <tag>"
 */
int mbedtls_asn1_get_sequence_of(unsigned char **p, const unsigned char *end,
                                 mbedtls_asn1_sequence *cur, int tag) {
  int ret;
  size_t len;
  mbedtls_asn1_buf *buf;

  /* Get main sequence tag */
  if ((ret = mbedtls_asn1_get_tag(
           p, end, &len, MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) !=
      0)
    return (ret);

  if (*p + len != end)
    return (MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);

  while (*p < end) {
    buf = &(cur->buf);
    buf->tag = **p;

    if ((ret = mbedtls_asn1_get_tag(p, end, &buf->len, tag)) != 0)
      return (ret);

    buf->p = *p;
    *p += buf->len;

    /* Allocate and assign next pointer */
    if (*p < end) {
      cur->next = (mbedtls_asn1_sequence *)mbedtls_calloc(
          1, sizeof(mbedtls_asn1_sequence));

      if (cur->next == NULL)
        return (MBEDTLS_ERR_ASN1_ALLOC_FAILED);

      cur = cur->next;
    }
  }

  /* Set final sequence entry's next pointer to NULL */
  cur->next = NULL;

  if (*p != end)
    return (MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);

  return (0);
}

int mbedtls_asn1_get_alg(unsigned char **p, const unsigned char *end,
                         mbedtls_asn1_buf *alg, mbedtls_asn1_buf *params) {
  int ret;
  size_t len;

  if ((ret = mbedtls_asn1_get_tag(
           p, end, &len, MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) !=
      0)
    return (ret);

  if ((end - *p) < 1)
    return (MBEDTLS_ERR_ASN1_OUT_OF_DATA);

  alg->tag = **p;
  end = *p + len;

  if ((ret = mbedtls_asn1_get_tag(p, end, &alg->len, MBEDTLS_ASN1_OID)) != 0)
    return (ret);

  alg->p = *p;
  *p += alg->len;

  if (*p == end) {
    mbedtls_zeroize(params, sizeof(mbedtls_asn1_buf));
    return (0);
  }

  params->tag = **p;
  (*p)++;

  if ((ret = mbedtls_asn1_get_len(p, end, &params->len)) != 0)
    return (ret);

  params->p = *p;
  *p += params->len;

  if (*p != end)
    return (MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);

  return (0);
}

int mbedtls_asn1_get_alg_null(unsigned char **p, const unsigned char *end,
                              mbedtls_asn1_buf *alg) {
  int ret;
  mbedtls_asn1_buf params;

  memset(&params, 0, sizeof(mbedtls_asn1_buf));

  if ((ret = mbedtls_asn1_get_alg(p, end, alg, &params)) != 0)
    return (ret);

  if ((params.tag != MBEDTLS_ASN1_NULL && params.tag != 0) || params.len != 0)
    return (MBEDTLS_ERR_ASN1_INVALID_DATA);

  return (0);
}

void mbedtls_asn1_free_named_data(mbedtls_asn1_named_data *cur) {
  if (cur == NULL)
    return;

  mbedtls_free(cur->oid.p);
  mbedtls_free(cur->val.p);

  mbedtls_zeroize(cur, sizeof(mbedtls_asn1_named_data));
}

void mbedtls_asn1_free_named_data_list(mbedtls_asn1_named_data **head) {
  mbedtls_asn1_named_data *cur;

  while ((cur = *head) != NULL) {
    *head = cur->next;
    mbedtls_asn1_free_named_data(cur);
    mbedtls_free(cur);
  }
}

mbedtls_asn1_named_data *
mbedtls_asn1_find_named_data(mbedtls_asn1_named_data *list, const char *oid,
                             size_t len) {
  while (list != NULL) {
    if (list->oid.len == len && memcmp(list->oid.p, oid, len) == 0) {
      break;
    }

    list = list->next;
  }

  return (list);
}

#endif /* MBEDTLS_ASN1_PARSE_C */