/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)

 * All rights reserved.

 *

 * This package is an SSL implementation written

 * by Eric Young (eay@cryptsoft.com).

 * The implementation was written so as to conform with Netscapes SSL.

 *

 * This library is free for commercial and non-commercial use as long as

 * the following conditions are aheared to.  The following conditions

 * apply to all code found in this distribution, be it the RC4, RSA,

 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation

 * included with this distribution is covered by the same copyright terms

 * except that the holder is Tim Hudson (tjh@cryptsoft.com).

 *

 * Copyright remains Eric Young's, and as such any Copyright notices in

 * the code are not to be removed.

 * If this package is used in a product, Eric Young should be given attribution

 * as the author of the parts of the library used.

 * This can be in the form of a textual message at program startup or

 * in documentation (online or textual) provided with the package.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 * 3. All advertising materials mentioning features or use of this software

 *    must display the following acknowledgement:

 *    "This product includes cryptographic software written by

 *     Eric Young (eay@cryptsoft.com)"

 *    The word 'cryptographic' can be left out if the rouines from the library

 *    being used are not cryptographic related :-).

 * 4. If you include any Windows specific code (or a derivative thereof) from

 *    the apps directory (application code) you must include an acknowledgement:

 *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"

 *

 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND

 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE

 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

 * SUCH DAMAGE.

 *

 * The licence and distribution terms for any publically available version or

 * derivative of this code cannot be changed.  i.e. this code cannot simply be

 * copied and put under another distribution licence

 * [including the GNU Public Licence.] */

#include <openssl/asn1.h>

#include <assert.h>

#include <string.h>

#include <openssl/asn1t.h>

#include <openssl/err.h>

#include <openssl/mem.h>

#include <openssl/obj.h>

#include <openssl/pool.h>

#include <openssl/thread.h>

#include "../internal.h"

#include "internal.h"

// Utility functions for manipulating fields and offsets

// Add 'offset' to 'addr'

#define offset2ptr(addr, offset) (void *)(((char *)(addr)) + (offset))

// Given an ASN1_ITEM CHOICE type return the selector value

int asn1_get_choice_selector(ASN1_VALUE **pval, const ASN1_ITEM *it) {

  int *sel = offset2ptr(*pval, it->utype);

  return *sel;

}

// Given an ASN1_ITEM CHOICE type set the selector value, return old value.

int asn1_set_choice_selector(ASN1_VALUE **pval, int value,

                             const ASN1_ITEM *it) {

  int *sel, ret;

  sel = offset2ptr(*pval, it->utype);

  ret = *sel;

  *sel = value;

  return ret;

}

static CRYPTO_refcount_t *asn1_get_references(ASN1_VALUE **pval,

                                              const ASN1_ITEM *it) {

  if (it->itype != ASN1_ITYPE_SEQUENCE) {

    return NULL;

  }

  const ASN1_AUX *aux = it->funcs;

  if (!aux || !(aux->flags & ASN1_AFLG_REFCOUNT)) {

    return NULL;

  }

  return offset2ptr(*pval, aux->ref_offset);

}

void asn1_refcount_set_one(ASN1_VALUE **pval, const ASN1_ITEM *it) {

  CRYPTO_refcount_t *references = asn1_get_references(pval, it);

  if (references != NULL) {

    *references = 1;

  }

}

int asn1_refcount_dec_and_test_zero(ASN1_VALUE **pval, const ASN1_ITEM *it) {

  CRYPTO_refcount_t *references = asn1_get_references(pval, it);

  if (references != NULL) {

    return CRYPTO_refcount_dec_and_test_zero(references);

  }

  return 1;

}

static ASN1_ENCODING *asn1_get_enc_ptr(ASN1_VALUE **pval, const ASN1_ITEM *it) {

  assert(it->itype == ASN1_ITYPE_SEQUENCE);

  const ASN1_AUX *aux;

  if (!pval || !*pval) {

    return NULL;

  }

  aux = it->funcs;

  if (!aux || !(aux->flags & ASN1_AFLG_ENCODING)) {

    return NULL;

  }

  return offset2ptr(*pval, aux->enc_offset);

}

void asn1_enc_init(ASN1_VALUE **pval, const ASN1_ITEM *it) {

  ASN1_ENCODING *enc = asn1_get_enc_ptr(pval, it);

  if (enc) {

    enc->enc = NULL;

    enc->len = 0;

    enc->buf = NULL;

  }

}

void asn1_enc_free(ASN1_VALUE **pval, const ASN1_ITEM *it) {

  ASN1_ENCODING *enc = asn1_get_enc_ptr(pval, it);

  if (enc) {

    asn1_encoding_clear(enc);

  }

}

int asn1_enc_save(ASN1_VALUE **pval, const uint8_t *in, size_t in_len,

                  const ASN1_ITEM *it, CRYPTO_BUFFER *buf) {

  ASN1_ENCODING *enc;

  enc = asn1_get_enc_ptr(pval, it);

  if (!enc) {

    return 1;

  }

  asn1_encoding_clear(enc);

  if (buf != NULL) {

    assert(CRYPTO_BUFFER_data(buf) <= in &&

           in + in_len <= CRYPTO_BUFFER_data(buf) + CRYPTO_BUFFER_len(buf));

    CRYPTO_BUFFER_up_ref(buf);

    enc->buf = buf;

    enc->enc = (uint8_t *)in;

  } else {

    enc->enc = OPENSSL_memdup(in, in_len);

    if (!enc->enc) {

      return 0;

    }

  }

  enc->len = in_len;

  return 1;

}

void asn1_encoding_clear(ASN1_ENCODING *enc) {

  if (enc->buf != NULL) {

    CRYPTO_BUFFER_free(enc->buf);

  } else {

    OPENSSL_free(enc->enc);

  }

  enc->enc = NULL;

  enc->len = 0;

  enc->buf = NULL;

}

int asn1_enc_restore(int *len, unsigned char **out, ASN1_VALUE **pval,

                     const ASN1_ITEM *it) {

  ASN1_ENCODING *enc = asn1_get_enc_ptr(pval, it);

  if (!enc || enc->len == 0) {

    return 0;

  }

  if (out) {

    OPENSSL_memcpy(*out, enc->enc, enc->len);

    *out += enc->len;

  }

  if (len) {

    *len = enc->len;

  }

  return 1;

}

// Given an ASN1_TEMPLATE get a pointer to a field

ASN1_VALUE **asn1_get_field_ptr(ASN1_VALUE **pval, const ASN1_TEMPLATE *tt) {

  ASN1_VALUE **pvaltmp = offset2ptr(*pval, tt->offset);

  // NOTE for BOOLEAN types the field is just a plain int so we can't return

  // int **, so settle for (int *).

  return pvaltmp;

}

// Handle ANY DEFINED BY template, find the selector, look up the relevant

// ASN1_TEMPLATE in the table and return it.

const ASN1_TEMPLATE *asn1_do_adb(ASN1_VALUE **pval, const ASN1_TEMPLATE *tt,

                                 int nullerr) {

  const ASN1_ADB *adb;

  const ASN1_ADB_TABLE *atbl;

  ASN1_VALUE **sfld;

  int i;

  if (!(tt->flags & ASN1_TFLG_ADB_MASK)) {

    return tt;

  }

  // Else ANY DEFINED BY ... get the table

  adb = ASN1_ADB_ptr(tt->item);

  // Get the selector field

  sfld = offset2ptr(*pval, adb->offset);

  // Check if NULL

  if (*sfld == NULL) {

    if (!adb->null_tt) {

      goto err;

    }

    return adb->null_tt;

  }

  // Convert type to a NID:

  // NB: don't check for NID_undef here because it

  // might be a legitimate value in the table

  assert(tt->flags & ASN1_TFLG_ADB_OID);

  int selector = OBJ_obj2nid((ASN1_OBJECT *)*sfld);

  // Try to find matching entry in table Maybe should check application types

  // first to allow application override? Might also be useful to have a flag

  // which indicates table is sorted and we can do a binary search. For now

  // stick to a linear search.

  for (atbl = adb->tbl, i = 0; i < adb->tblcount; i++, atbl++) {

    if (atbl->value == selector) {

      return &atbl->tt;

    }

  }

  // FIXME: need to search application table too

  // No match, return default type

  if (!adb->default_tt) {

    goto err;

  }

  return adb->default_tt;

err:

  // FIXME: should log the value or OID of unsupported type

  if (nullerr) {

    OPENSSL_PUT_ERROR(ASN1, ASN1_R_UNSUPPORTED_ANY_DEFINED_BY_TYPE);

  }

  return NULL;

}