/* 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/digest.h>

#include <string.h>

#include <openssl/blake2.h>

#include <openssl/bytestring.h>

#include <openssl/obj.h>

#include <openssl/md4.h>

#include <openssl/md5.h>

#include <openssl/nid.h>

#include "../asn1/internal.h"

#include "../internal.h"

#include "../fipsmodule/digest/internal.h"

struct nid_to_digest {

  int nid;

  const EVP_MD* (*md_func)(void);

  const char *short_name;

  const char *long_name;

};

static const struct nid_to_digest nid_to_digest_mapping[] = {

    {NID_md4, EVP_md4, SN_md4, LN_md4},

    {NID_md5, EVP_md5, SN_md5, LN_md5},

    {NID_sha1, EVP_sha1, SN_sha1, LN_sha1},

    {NID_sha224, EVP_sha224, SN_sha224, LN_sha224},

    {NID_sha256, EVP_sha256, SN_sha256, LN_sha256},

    {NID_sha384, EVP_sha384, SN_sha384, LN_sha384},

    {NID_sha512, EVP_sha512, SN_sha512, LN_sha512},

    {NID_sha512_256, EVP_sha512_256, SN_sha512_256, LN_sha512_256},

    {NID_md5_sha1, EVP_md5_sha1, SN_md5_sha1, LN_md5_sha1},

    // As a remnant of signing |EVP_MD|s, OpenSSL returned the corresponding

    // hash function when given a signature OID. To avoid unintended lax parsing

    // of hash OIDs, this is no longer supported for lookup by OID or NID.

    // Node.js, however, exposes |EVP_get_digestbyname|'s full behavior to

    // consumers so we retain it there.

    {NID_undef, EVP_sha1, SN_dsaWithSHA, LN_dsaWithSHA},

    {NID_undef, EVP_sha1, SN_dsaWithSHA1, LN_dsaWithSHA1},

    {NID_undef, EVP_sha1, SN_ecdsa_with_SHA1, NULL},

    {NID_undef, EVP_md5, SN_md5WithRSAEncryption, LN_md5WithRSAEncryption},

    {NID_undef, EVP_sha1, SN_sha1WithRSAEncryption, LN_sha1WithRSAEncryption},

    {NID_undef, EVP_sha224, SN_sha224WithRSAEncryption,

     LN_sha224WithRSAEncryption},

    {NID_undef, EVP_sha256, SN_sha256WithRSAEncryption,

     LN_sha256WithRSAEncryption},

    {NID_undef, EVP_sha384, SN_sha384WithRSAEncryption,

     LN_sha384WithRSAEncryption},

    {NID_undef, EVP_sha512, SN_sha512WithRSAEncryption,

     LN_sha512WithRSAEncryption},

};

const EVP_MD* EVP_get_digestbynid(int nid) {

  if (nid == NID_undef) {

    // Skip the |NID_undef| entries in |nid_to_digest_mapping|.

    return NULL;

  }

  for (unsigned i = 0; i < OPENSSL_ARRAY_SIZE(nid_to_digest_mapping); i++) {

    if (nid_to_digest_mapping[i].nid == nid) {

      return nid_to_digest_mapping[i].md_func();

    }

  }

  return NULL;

}

static const struct {

  uint8_t oid[9];

  uint8_t oid_len;

  int nid;

} kMDOIDs[] = {

  // 1.2.840.113549.2.4

  { {0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x02, 0x04}, 8, NID_md4 },

  // 1.2.840.113549.2.5

  { {0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x02, 0x05}, 8, NID_md5 },

  // 1.3.14.3.2.26

  { {0x2b, 0x0e, 0x03, 0x02, 0x1a}, 5, NID_sha1 },

  // 2.16.840.1.101.3.4.2.1

  { {0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01}, 9, NID_sha256 },

  // 2.16.840.1.101.3.4.2.2

  { {0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x02}, 9, NID_sha384 },

  // 2.16.840.1.101.3.4.2.3

  { {0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03}, 9, NID_sha512 },

  // 2.16.840.1.101.3.4.2.4

  { {0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x04}, 9, NID_sha224 },

};

static const EVP_MD *cbs_to_md(const CBS *cbs) {

  for (size_t i = 0; i < OPENSSL_ARRAY_SIZE(kMDOIDs); i++) {

    if (CBS_len(cbs) == kMDOIDs[i].oid_len &&

        OPENSSL_memcmp(CBS_data(cbs), kMDOIDs[i].oid, kMDOIDs[i].oid_len) ==

            0) {

      return EVP_get_digestbynid(kMDOIDs[i].nid);

    }

  }

  return NULL;

}

const EVP_MD *EVP_get_digestbyobj(const ASN1_OBJECT *obj) {

  // Handle objects with no corresponding OID. Note we don't use |OBJ_obj2nid|

  // here to avoid pulling in the OID table.

  if (obj->nid != NID_undef) {

    return EVP_get_digestbynid(obj->nid);

  }

  CBS cbs;

  CBS_init(&cbs, OBJ_get0_data(obj), OBJ_length(obj));

  return cbs_to_md(&cbs);

}

const EVP_MD *EVP_parse_digest_algorithm(CBS *cbs) {

  CBS algorithm, oid;

  if (!CBS_get_asn1(cbs, &algorithm, CBS_ASN1_SEQUENCE) ||

      !CBS_get_asn1(&algorithm, &oid, CBS_ASN1_OBJECT)) {

    OPENSSL_PUT_ERROR(DIGEST, DIGEST_R_DECODE_ERROR);

    return NULL;

  }

  const EVP_MD *ret = cbs_to_md(&oid);

  if (ret == NULL) {

    OPENSSL_PUT_ERROR(DIGEST, DIGEST_R_UNKNOWN_HASH);

    return NULL;

  }

  // The parameters, if present, must be NULL. Historically, whether the NULL

  // was included or omitted was not well-specified. When parsing an

  // AlgorithmIdentifier, we allow both. (Note this code is not used when

  // verifying RSASSA-PKCS1-v1_5 signatures.)

  if (CBS_len(&algorithm) > 0) {

    CBS param;

    if (!CBS_get_asn1(&algorithm, &param, CBS_ASN1_NULL) ||

        CBS_len(&param) != 0 ||

        CBS_len(&algorithm) != 0) {

      OPENSSL_PUT_ERROR(DIGEST, DIGEST_R_DECODE_ERROR);

      return NULL;

    }

  }

  return ret;

}

int EVP_marshal_digest_algorithm(CBB *cbb, const EVP_MD *md) {

  CBB algorithm, oid, null;

  if (!CBB_add_asn1(cbb, &algorithm, CBS_ASN1_SEQUENCE) ||

      !CBB_add_asn1(&algorithm, &oid, CBS_ASN1_OBJECT)) {

    return 0;

  }

  int found = 0;

  int nid = EVP_MD_type(md);

  for (size_t i = 0; i < OPENSSL_ARRAY_SIZE(kMDOIDs); i++) {

    if (nid == kMDOIDs[i].nid) {

      if (!CBB_add_bytes(&oid, kMDOIDs[i].oid, kMDOIDs[i].oid_len)) {

        return 0;

      }

      found = 1;

      break;

    }

  }

  if (!found) {

    OPENSSL_PUT_ERROR(DIGEST, DIGEST_R_UNKNOWN_HASH);

    return 0;

  }

  // TODO(crbug.com/boringssl/710): Is this correct? See RFC 4055, section 2.1.

  if (!CBB_add_asn1(&algorithm, &null, CBS_ASN1_NULL) ||

      !CBB_flush(cbb)) {

    return 0;

  }

  return 1;

}

const EVP_MD *EVP_get_digestbyname(const char *name) {

  for (unsigned i = 0; i < OPENSSL_ARRAY_SIZE(nid_to_digest_mapping); i++) {

    const char *short_name = nid_to_digest_mapping[i].short_name;

    const char *long_name = nid_to_digest_mapping[i].long_name;

    if ((short_name && strcmp(short_name, name) == 0) ||

        (long_name && strcmp(long_name, name) == 0)) {

      return nid_to_digest_mapping[i].md_func();

    }

  }

  return NULL;

}

static void blake2b256_init(EVP_MD_CTX *ctx) { BLAKE2B256_Init(ctx->md_data); }

static void blake2b256_update(EVP_MD_CTX *ctx, const void *data, size_t len) {

  BLAKE2B256_Update(ctx->md_data, data, len);

}

static void blake2b256_final(EVP_MD_CTX *ctx, uint8_t *md) {

  BLAKE2B256_Final(md, ctx->md_data);

}

static const EVP_MD evp_md_blake2b256 = {

  NID_undef,

  BLAKE2B256_DIGEST_LENGTH,

  0,

  blake2b256_init,

  blake2b256_update,

  blake2b256_final,

  BLAKE2B_CBLOCK,

  sizeof(BLAKE2B_CTX),

};

const EVP_MD *EVP_blake2b256(void) { return &evp_md_blake2b256; }

static void md4_init(EVP_MD_CTX *ctx) {

  BSSL_CHECK(MD4_Init(ctx->md_data));

}

static void md4_update(EVP_MD_CTX *ctx, const void *data, size_t count) {

  BSSL_CHECK(MD4_Update(ctx->md_data, data, count));

}

static void md4_final(EVP_MD_CTX *ctx, uint8_t *out) {

  BSSL_CHECK(MD4_Final(out, ctx->md_data));

}

static const EVP_MD evp_md_md4 = {

  NID_md4,

  MD4_DIGEST_LENGTH,

  0,

  md4_init,

  md4_update,

  md4_final,

  64,

  sizeof(MD4_CTX),

};

const EVP_MD *EVP_md4(void) { return &evp_md_md4; }

static void md5_init(EVP_MD_CTX *ctx) {

  BSSL_CHECK(MD5_Init(ctx->md_data));

}

static void md5_update(EVP_MD_CTX *ctx, const void *data, size_t count) {

  BSSL_CHECK(MD5_Update(ctx->md_data, data, count));

}

static void md5_final(EVP_MD_CTX *ctx, uint8_t *out) {

  BSSL_CHECK(MD5_Final(out, ctx->md_data));

}

static const EVP_MD evp_md_md5 = {

  NID_md5,

  MD5_DIGEST_LENGTH,

  0,

  md5_init,

  md5_update,

  md5_final,

  64,

  sizeof(MD5_CTX),

};

const EVP_MD *EVP_md5(void) { return &evp_md_md5; }

typedef struct {

  MD5_CTX md5;

  SHA_CTX sha1;

} MD5_SHA1_CTX;

static void md5_sha1_init(EVP_MD_CTX *md_ctx) {

  MD5_SHA1_CTX *ctx = md_ctx->md_data;

  BSSL_CHECK(MD5_Init(&ctx->md5) && SHA1_Init(&ctx->sha1));

}

static void md5_sha1_update(EVP_MD_CTX *md_ctx, const void *data,

                            size_t count) {

  MD5_SHA1_CTX *ctx = md_ctx->md_data;

  BSSL_CHECK(MD5_Update(&ctx->md5, data, count) &&

        SHA1_Update(&ctx->sha1, data, count));

}

static void md5_sha1_final(EVP_MD_CTX *md_ctx, uint8_t *out) {

  MD5_SHA1_CTX *ctx = md_ctx->md_data;

  BSSL_CHECK(MD5_Final(out, &ctx->md5) &&

        SHA1_Final(out + MD5_DIGEST_LENGTH, &ctx->sha1));

}

const EVP_MD evp_md_md5_sha1 = {

  NID_md5_sha1,

  MD5_DIGEST_LENGTH + SHA_DIGEST_LENGTH,

  0,

  md5_sha1_init,

  md5_sha1_update,

  md5_sha1_final,

  64,

  sizeof(MD5_SHA1_CTX),

};

const EVP_MD *EVP_md5_sha1(void) { return &evp_md_md5_sha1; }