/* $OpenBSD: s3_enc.c,v 1.60 2015/06/17 14:27:56 jsing Exp $ */
/* 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.]
 */
/* ====================================================================
 * Copyright (c) 1998-2007 The OpenSSL Project.  All rights reserved.
 *
 * 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 above 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 acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
 *
 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
 *    endorse or promote products derived from this software without
 *    prior written permission. For written permission, please contact
 *    openssl-core@openssl.org.
 *
 * 5. Products derived from this software may not be called "OpenSSL"
 *    nor may "OpenSSL" appear in their names without prior written
 *    permission of the OpenSSL Project.
 *
 * 6. Redistributions of any form whatsoever must retain the following
 *    acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
 *
 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
 * EXPRESSED 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 OpenSSL PROJECT OR
 * ITS 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.
 * ====================================================================
 *
 * This product includes cryptographic software written by Eric Young
 * (eay@cryptsoft.com).  This product includes software written by Tim
 * Hudson (tjh@cryptsoft.com).
 *
 */
/* ====================================================================
 * Copyright 2005 Nokia. All rights reserved.
 *
 * The portions of the attached software ("Contribution") is developed by
 * Nokia Corporation and is licensed pursuant to the OpenSSL open source
 * license.
 *
 * The Contribution, originally written by Mika Kousa and Pasi Eronen of
 * Nokia Corporation, consists of the "PSK" (Pre-Shared Key) ciphersuites
 * support (see RFC 4279) to OpenSSL.
 *
 * No patent licenses or other rights except those expressly stated in
 * the OpenSSL open source license shall be deemed granted or received
 * expressly, by implication, estoppel, or otherwise.
 *
 * No assurances are provided by Nokia that the Contribution does not
 * infringe the patent or other intellectual property rights of any third
 * party or that the license provides you with all the necessary rights
 * to make use of the Contribution.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. IN
 * ADDITION TO THE DISCLAIMERS INCLUDED IN THE LICENSE, NOKIA
 * SPECIFICALLY DISCLAIMS ANY LIABILITY FOR CLAIMS BROUGHT BY YOU OR ANY
 * OTHER ENTITY BASED ON INFRINGEMENT OF INTELLECTUAL PROPERTY RIGHTS OR
 * OTHERWISE.
 */

#include <stdio.h>

#include "ssl_locl.h"

#include <openssl/evp.h>
#include <openssl/md5.h>

static unsigned char ssl3_pad_1[48] = {
	0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36,
	0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36,
	0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36,
	0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36,
	0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36,
	0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36
};

static unsigned char ssl3_pad_2[48] = {
	0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c,
	0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c,
	0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c,
	0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c,
	0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c,
	0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c
};

static int ssl3_handshake_mac(SSL *s, int md_nid, const char *sender,
    int len, unsigned char *p);

static int
ssl3_generate_key_block(SSL *s, unsigned char *km, int num)
{
	EVP_MD_CTX m5;
	EVP_MD_CTX s1;
	unsigned char buf[16], smd[SHA_DIGEST_LENGTH];
	unsigned char c = 'A';
	unsigned int i, j, k;

	k = 0;
	EVP_MD_CTX_init(&m5);
	EVP_MD_CTX_init(&s1);
	for (i = 0; (int)i < num; i += MD5_DIGEST_LENGTH) {
		k++;
		if (k > sizeof buf) {
			/* bug: 'buf' is too small for this ciphersuite */
			SSLerr(SSL_F_SSL3_GENERATE_KEY_BLOCK,
			    ERR_R_INTERNAL_ERROR);
			return 0;
		}

		for (j = 0; j < k; j++)
			buf[j] = c;
		c++;
		if (!EVP_DigestInit_ex(&s1, EVP_sha1(), NULL))
			return 0;
		EVP_DigestUpdate(&s1, buf, k);
		EVP_DigestUpdate(&s1, s->session->master_key,
		    s->session->master_key_length);
		EVP_DigestUpdate(&s1, s->s3->server_random, SSL3_RANDOM_SIZE);
		EVP_DigestUpdate(&s1, s->s3->client_random, SSL3_RANDOM_SIZE);
		EVP_DigestFinal_ex(&s1, smd, NULL);

		if (!EVP_DigestInit_ex(&m5, EVP_md5(), NULL))
			return 0;
		EVP_DigestUpdate(&m5, s->session->master_key,
		    s->session->master_key_length);
		EVP_DigestUpdate(&m5, smd, SHA_DIGEST_LENGTH);
		if ((int)(i + MD5_DIGEST_LENGTH) > num) {
			EVP_DigestFinal_ex(&m5, smd, NULL);
			memcpy(km, smd, (num - i));
		} else
			EVP_DigestFinal_ex(&m5, km, NULL);

		km += MD5_DIGEST_LENGTH;
	}
	OPENSSL_cleanse(smd, SHA_DIGEST_LENGTH);
	EVP_MD_CTX_cleanup(&m5);
	EVP_MD_CTX_cleanup(&s1);
	return 1;
}

int
ssl3_change_cipher_state(SSL *s, int which)
{
	const unsigned char *client_write_mac_secret, *server_write_mac_secret;
	const unsigned char *client_write_key, *server_write_key;
	const unsigned char *client_write_iv, *server_write_iv;
	const unsigned char *mac_secret, *key, *iv;
	unsigned char *key_block;
	int mac_len, key_len, iv_len;
	char is_read, use_client_keys;
	EVP_CIPHER_CTX *cipher_ctx;
	const EVP_CIPHER *cipher;
	const EVP_MD *mac;


	cipher = s->s3->tmp.new_sym_enc;
	mac = s->s3->tmp.new_hash;

	/* mac == NULL will lead to a crash later */
	OPENSSL_assert(mac);

	/*
	 * is_read is true if we have just read a ChangeCipherSpec message,
	 * that is we need to update the read cipherspec. Otherwise we have
	 * just written one.
	 */
	is_read = (which & SSL3_CC_READ) != 0;

	/*
	 * use_client_keys is true if we wish to use the keys for the "client
	 * write" direction. This is the case if we're a client sending a
	 * ChangeCipherSpec, or a server reading a client's ChangeCipherSpec.
	 */
	use_client_keys = ((which == SSL3_CHANGE_CIPHER_CLIENT_WRITE) ||
	    (which == SSL3_CHANGE_CIPHER_SERVER_READ));


	if (is_read) {
		EVP_CIPHER_CTX_free(s->enc_read_ctx);
		s->enc_read_ctx = NULL;
		if ((cipher_ctx = EVP_CIPHER_CTX_new()) == NULL)
			goto err;
		s->enc_read_ctx = cipher_ctx;

		if (ssl_replace_hash(&s->read_hash, mac) == NULL)
			goto err;
	} else {
		EVP_CIPHER_CTX_free(s->enc_write_ctx);
		s->enc_write_ctx = NULL;
		if ((cipher_ctx = EVP_CIPHER_CTX_new()) == NULL)
			goto err;
		s->enc_write_ctx = cipher_ctx;

		if (ssl_replace_hash(&s->write_hash, mac) == NULL)
			goto err;
	}

	memset(is_read ? s->s3->read_sequence : s->s3->write_sequence,
	    0, SSL3_SEQUENCE_SIZE);

	mac_len = EVP_MD_size(mac);
	key_len = EVP_CIPHER_key_length(cipher);
	iv_len = EVP_CIPHER_iv_length(cipher);

	if (mac_len < 0)
		goto err2;

	key_block = s->s3->tmp.key_block;
	client_write_mac_secret = key_block;
	key_block += mac_len;
	server_write_mac_secret = key_block;
	key_block += mac_len;
	client_write_key = key_block;
	key_block += key_len;
	server_write_key = key_block;
	key_block += key_len;
	client_write_iv = key_block;
	key_block += iv_len;
	server_write_iv = key_block;
	key_block += iv_len;

	if (use_client_keys) {
		mac_secret = client_write_mac_secret;
		key = client_write_key;
		iv = client_write_iv;
	} else {
		mac_secret = server_write_mac_secret;
		key = server_write_key;
		iv = server_write_iv;
	}

	if (key_block - s->s3->tmp.key_block != s->s3->tmp.key_block_length) {
		SSLerr(SSL_F_SSL3_CHANGE_CIPHER_STATE, ERR_R_INTERNAL_ERROR);
		goto err2;
	}

	memcpy(is_read ? s->s3->read_mac_secret : s->s3->write_mac_secret,
	    mac_secret, mac_len);

	EVP_CipherInit_ex(cipher_ctx, cipher, NULL, key, iv, !is_read);

	return (1);
err:
	SSLerr(SSL_F_SSL3_CHANGE_CIPHER_STATE, ERR_R_MALLOC_FAILURE);
err2:
	return (0);
}

int
ssl3_setup_key_block(SSL *s)
{
	int key_block_len, mac_len, key_len, iv_len;
	unsigned char *key_block;
	const EVP_CIPHER *cipher;
	const EVP_MD *mac;
	int ret = 0;

	if (s->s3->tmp.key_block_length != 0)
		return (1);

	if (!ssl_cipher_get_evp(s->session, &cipher, &mac, NULL, NULL)) {
		SSLerr(SSL_F_SSL3_SETUP_KEY_BLOCK,
		    SSL_R_CIPHER_OR_HASH_UNAVAILABLE);
		return (0);
	}

	s->s3->tmp.new_sym_enc = cipher;
	s->s3->tmp.new_hash = mac;

	mac_len = EVP_MD_size(mac);
	key_len = EVP_CIPHER_key_length(cipher);
	iv_len = EVP_CIPHER_iv_length(cipher);

	if (mac_len < 0)
		return 0;

	ssl3_cleanup_key_block(s);

	if ((key_block = reallocarray(NULL, mac_len + key_len + iv_len, 2))
	    == NULL)
		goto err;
	key_block_len = (mac_len + key_len + iv_len) * 2;

	s->s3->tmp.key_block_length = key_block_len;
	s->s3->tmp.key_block = key_block;

	ret = ssl3_generate_key_block(s, key_block, key_block_len);

	if (!(s->options & SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS)) {
		/*
		 * Enable vulnerability countermeasure for CBC ciphers with
		 * known-IV problem (http://www.openssl.org/~bodo/tls-cbc.txt)
		 */
		s->s3->need_empty_fragments = 1;

		if (s->session->cipher != NULL) {
			if (s->session->cipher->algorithm_enc == SSL_eNULL)
				s->s3->need_empty_fragments = 0;

#ifndef OPENSSL_NO_RC4
			if (s->session->cipher->algorithm_enc == SSL_RC4)
				s->s3->need_empty_fragments = 0;
#endif
		}
	}

	return ret;

err:
	SSLerr(SSL_F_SSL3_SETUP_KEY_BLOCK, ERR_R_MALLOC_FAILURE);
	return (0);
}

void
ssl3_cleanup_key_block(SSL *s)
{
	if (s->s3->tmp.key_block != NULL) {
		OPENSSL_cleanse(s->s3->tmp.key_block,
		    s->s3->tmp.key_block_length);
		free(s->s3->tmp.key_block);
		s->s3->tmp.key_block = NULL;
	}
	s->s3->tmp.key_block_length = 0;
}

/* ssl3_enc encrypts/decrypts the record in |s->wrec| / |s->rrec|, respectively.
 *
 * Returns:
 *   0: (in non-constant time) if the record is publically invalid (i.e. too
 *       short etc).
 *   1: if the record's padding is valid / the encryption was successful.
 *   -1: if the record's padding is invalid or, if sending, an internal error
 *       occured.
 */
int
ssl3_enc(SSL *s, int send)
{
	SSL3_RECORD *rec;
	EVP_CIPHER_CTX *ds;
	unsigned long l;
	int bs, i, mac_size = 0;
	const EVP_CIPHER *enc;

	if (send) {
		ds = s->enc_write_ctx;
		rec = &(s->s3->wrec);
		if (s->enc_write_ctx == NULL)
			enc = NULL;
		else
			enc = EVP_CIPHER_CTX_cipher(s->enc_write_ctx);
	} else {
		ds = s->enc_read_ctx;
		rec = &(s->s3->rrec);
		if (s->enc_read_ctx == NULL)
			enc = NULL;
		else
			enc = EVP_CIPHER_CTX_cipher(s->enc_read_ctx);
	}

	if ((s->session == NULL) || (ds == NULL) || (enc == NULL)) {
		memmove(rec->data, rec->input, rec->length);
		rec->input = rec->data;
	} else {
		l = rec->length;
		bs = EVP_CIPHER_block_size(ds->cipher);

		/* COMPRESS */

		if ((bs != 1) && send) {
			i = bs - ((int)l % bs);

			/* we need to add 'i-1' padding bytes */
			l += i;
			/* the last of these zero bytes will be overwritten
			 * with the padding length. */
			memset(&rec->input[rec->length], 0, i);
			rec->length += i;
			rec->input[l - 1] = (i - 1);
		}

		if (!send) {
			if (l == 0 || l % bs != 0)
				return 0;
			/* otherwise, rec->length >= bs */
		}

		EVP_Cipher(ds, rec->data, rec->input, l);

		if (EVP_MD_CTX_md(s->read_hash) != NULL)
			mac_size = EVP_MD_CTX_size(s->read_hash);
		if ((bs != 1) && !send)
			return ssl3_cbc_remove_padding(s, rec, bs, mac_size);
	}
	return (1);
}

int
ssl3_init_finished_mac(SSL *s)
{
	BIO_free(s->s3->handshake_buffer);
	ssl3_free_digest_list(s);

	s->s3->handshake_buffer = BIO_new(BIO_s_mem());
	if (s->s3->handshake_buffer == NULL)
		return (0);

	(void)BIO_set_close(s->s3->handshake_buffer, BIO_CLOSE);

	return (1);
}

void
ssl3_free_digest_list(SSL *s)
{
	int i;

	if (s == NULL)
		return;

	if (s->s3->handshake_dgst == NULL)
		return;
	for (i = 0; i < SSL_MAX_DIGEST; i++) {
		if (s->s3->handshake_dgst[i])
			EVP_MD_CTX_destroy(s->s3->handshake_dgst[i]);
	}
	free(s->s3->handshake_dgst);
	s->s3->handshake_dgst = NULL;
}

void
ssl3_finish_mac(SSL *s, const unsigned char *buf, int len)
{
	if (s->s3->handshake_buffer &&
	    !(s->s3->flags & TLS1_FLAGS_KEEP_HANDSHAKE)) {
		BIO_write(s->s3->handshake_buffer, (void *)buf, len);
	} else {
		int i;
		for (i = 0; i < SSL_MAX_DIGEST; i++) {
			if (s->s3->handshake_dgst[i]!= NULL)
				EVP_DigestUpdate(s->s3->handshake_dgst[i], buf, len);
		}
	}
}

int
ssl3_digest_cached_records(SSL *s)
{
	int i;
	long mask;
	const EVP_MD *md;
	long hdatalen;
	void *hdata;

	ssl3_free_digest_list(s);

	s->s3->handshake_dgst = calloc(SSL_MAX_DIGEST, sizeof(EVP_MD_CTX *));
	if (s->s3->handshake_dgst == NULL) {
		SSLerr(SSL_F_SSL3_DIGEST_CACHED_RECORDS, ERR_R_MALLOC_FAILURE);
		return 0;
	}
	hdatalen = BIO_get_mem_data(s->s3->handshake_buffer, &hdata);
	if (hdatalen <= 0) {
		SSLerr(SSL_F_SSL3_DIGEST_CACHED_RECORDS,
		    SSL_R_BAD_HANDSHAKE_LENGTH);
		return 0;
	}

	/* Loop through bits of the algorithm2 field and create MD contexts. */
	for (i = 0; ssl_get_handshake_digest(i, &mask, &md); i++) {
		if ((mask & ssl_get_algorithm2(s)) && md) {
			s->s3->handshake_dgst[i] = EVP_MD_CTX_create();
			if (s->s3->handshake_dgst[i] == NULL) {
				SSLerr(SSL_F_SSL3_DIGEST_CACHED_RECORDS,
				    ERR_R_MALLOC_FAILURE);
				return 0;
			}
			if (!EVP_DigestInit_ex(s->s3->handshake_dgst[i],
			    md, NULL)) {
				EVP_MD_CTX_destroy(s->s3->handshake_dgst[i]);
				return 0;
			}
			if (!EVP_DigestUpdate(s->s3->handshake_dgst[i], hdata,
			    hdatalen))
				return 0;
		}
	}

	if (!(s->s3->flags & TLS1_FLAGS_KEEP_HANDSHAKE)) {
		BIO_free(s->s3->handshake_buffer);
		s->s3->handshake_buffer = NULL;
	}

	return 1;
}

int
ssl3_cert_verify_mac(SSL *s, int md_nid, unsigned char *p)
{
	return (ssl3_handshake_mac(s, md_nid, NULL, 0, p));
}

int
ssl3_final_finish_mac(SSL *s, const char *sender, int len, unsigned char *p)
{
	int ret_md5, ret_sha1;

	ret_md5 = ssl3_handshake_mac(s, NID_md5, sender, len, p);
	if (ret_md5 == 0)
		return 0;
	p += ret_md5;
	ret_sha1 = ssl3_handshake_mac(s, NID_sha1, sender, len, p);
	if (ret_sha1 == 0)
		return 0;
	return (ret_md5 + ret_sha1);
}

static int
ssl3_handshake_mac(SSL *s, int md_nid, const char *sender, int len,
    unsigned char *p)
{
	unsigned int ret;
	int npad, n;
	unsigned int i;
	unsigned char md_buf[EVP_MAX_MD_SIZE];
	EVP_MD_CTX ctx, *d = NULL;

	if (s->s3->handshake_buffer)
		if (!ssl3_digest_cached_records(s))
			return 0;

	/* Search for digest of specified type in the handshake_dgst array. */
	for (i = 0; i < SSL_MAX_DIGEST; i++) {
		if (s->s3->handshake_dgst[i] &&
		    EVP_MD_CTX_type(s->s3->handshake_dgst[i]) == md_nid) {
			d = s->s3->handshake_dgst[i];
			break;
		}
	}
	if (!d) {
		SSLerr(SSL_F_SSL3_HANDSHAKE_MAC, SSL_R_NO_REQUIRED_DIGEST);
		return 0;
	}
	EVP_MD_CTX_init(&ctx);
	if (!EVP_MD_CTX_copy_ex(&ctx, d))
		return 0;
	n = EVP_MD_CTX_size(&ctx);
	if (n < 0)
		return 0;

	npad = (48 / n) * n;
	if (sender != NULL)
		EVP_DigestUpdate(&ctx, sender, len);
	EVP_DigestUpdate(&ctx, s->session->master_key,
	    s->session->master_key_length);
	EVP_DigestUpdate(&ctx, ssl3_pad_1, npad);
	EVP_DigestFinal_ex(&ctx, md_buf, &i);

	if (!EVP_DigestInit_ex(&ctx, EVP_MD_CTX_md(&ctx), NULL))
		return 0;
	EVP_DigestUpdate(&ctx, s->session->master_key,
	    s->session->master_key_length);
	EVP_DigestUpdate(&ctx, ssl3_pad_2, npad);
	EVP_DigestUpdate(&ctx, md_buf, i);
	EVP_DigestFinal_ex(&ctx, p, &ret);

	EVP_MD_CTX_cleanup(&ctx);

	return ((int)ret);
}

int
n_ssl3_mac(SSL *ssl, unsigned char *md, int send)
{
	SSL3_RECORD *rec;
	unsigned char *mac_sec, *seq;
	EVP_MD_CTX md_ctx;
	const EVP_MD_CTX *hash;
	unsigned char *p, rec_char;
	size_t md_size, orig_len;
	int npad;
	int t;

	if (send) {
		rec = &(ssl->s3->wrec);
		mac_sec = &(ssl->s3->write_mac_secret[0]);
		seq = &(ssl->s3->write_sequence[0]);
		hash = ssl->write_hash;
	} else {
		rec = &(ssl->s3->rrec);
		mac_sec = &(ssl->s3->read_mac_secret[0]);
		seq = &(ssl->s3->read_sequence[0]);
		hash = ssl->read_hash;
	}

	t = EVP_MD_CTX_size(hash);
	if (t < 0)
		return -1;
	md_size = t;
	npad = (48 / md_size) * md_size;

	/* kludge: ssl3_cbc_remove_padding passes padding length in rec->type */
	orig_len = rec->length + md_size + ((unsigned int)rec->type >> 8);
	rec->type &= 0xff;

	if (!send &&
	    EVP_CIPHER_CTX_mode(ssl->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
	    ssl3_cbc_record_digest_supported(hash)) {
		/* This is a CBC-encrypted record. We must avoid leaking any
		 * timing-side channel information about how many blocks of
		 * data we are hashing because that gives an attacker a
		 * timing-oracle. */

		/* npad is, at most, 48 bytes and that's with MD5:
		 *   16 + 48 + 8 (sequence bytes) + 1 + 2 = 75.
		 *
		 * With SHA-1 (the largest hash speced for SSLv3) the hash size
		 * goes up 4, but npad goes down by 8, resulting in a smaller
		 * total size. */
		unsigned char header[75];
		unsigned j = 0;
		memcpy(header + j, mac_sec, md_size);
		j += md_size;
		memcpy(header + j, ssl3_pad_1, npad);
		j += npad;
		memcpy(header + j, seq, 8);
		j += 8;
		header[j++] = rec->type;
		header[j++] = rec->length >> 8;
		header[j++] = rec->length & 0xff;

		if (!ssl3_cbc_digest_record(hash, md, &md_size, header,
		    rec->input, rec->length + md_size, orig_len, mac_sec,
		    md_size, 1 /* is SSLv3 */))
			return (-1);
	} else {
		unsigned int md_size_u;
		/* Chop the digest off the end :-) */
		EVP_MD_CTX_init(&md_ctx);

		if (!EVP_MD_CTX_copy_ex(&md_ctx, hash))
			return (-1);
		EVP_DigestUpdate(&md_ctx, mac_sec, md_size);
		EVP_DigestUpdate(&md_ctx, ssl3_pad_1, npad);
		EVP_DigestUpdate(&md_ctx, seq, 8);
		rec_char = rec->type;
		EVP_DigestUpdate(&md_ctx, &rec_char, 1);
		p = md;
		s2n(rec->length, p);
		EVP_DigestUpdate(&md_ctx, md, 2);
		EVP_DigestUpdate(&md_ctx, rec->input, rec->length);
		EVP_DigestFinal_ex(&md_ctx, md, NULL);

		if (!EVP_MD_CTX_copy_ex(&md_ctx, hash))
			return (-1);
		EVP_DigestUpdate(&md_ctx, mac_sec, md_size);
		EVP_DigestUpdate(&md_ctx, ssl3_pad_2, npad);
		EVP_DigestUpdate(&md_ctx, md, md_size);
		EVP_DigestFinal_ex(&md_ctx, md, &md_size_u);
		md_size = md_size_u;

		EVP_MD_CTX_cleanup(&md_ctx);
	}

	ssl3_record_sequence_increment(seq);

	return (md_size);
}

void
ssl3_record_sequence_increment(unsigned char *seq)
{
	int i;

	for (i = SSL3_SEQUENCE_SIZE - 1; i >= 0; i--) {
		if (++seq[i] != 0)
			break;
	}
}

int
ssl3_generate_master_secret(SSL *s, unsigned char *out, unsigned char *p,
    int len)
{
	static const unsigned char *salt[3] = { "A", "BB", "CCC", };
	unsigned char buf[EVP_MAX_MD_SIZE];
	EVP_MD_CTX ctx;
	int i, ret = 0;
	unsigned int n;

	EVP_MD_CTX_init(&ctx);
	for (i = 0; i < 3; i++) {
		if (!EVP_DigestInit_ex(&ctx, s->ctx->sha1, NULL))
			return 0;
		EVP_DigestUpdate(&ctx, salt[i], strlen((const char *)salt[i]));
		EVP_DigestUpdate(&ctx, p, len);
		EVP_DigestUpdate(&ctx, s->s3->client_random, SSL3_RANDOM_SIZE);
		EVP_DigestUpdate(&ctx, s->s3->server_random, SSL3_RANDOM_SIZE);
		EVP_DigestFinal_ex(&ctx, buf, &n);

		if (!EVP_DigestInit_ex(&ctx, s->ctx->md5, NULL))
			return 0;
		EVP_DigestUpdate(&ctx, p, len);
		EVP_DigestUpdate(&ctx, buf, n);
		EVP_DigestFinal_ex(&ctx, out, &n);
		out += n;
		ret += n;
	}
	EVP_MD_CTX_cleanup(&ctx);
	return (ret);
}

int
ssl3_alert_code(int code)
{
	switch (code) {
	case SSL_AD_CLOSE_NOTIFY:
		return (SSL3_AD_CLOSE_NOTIFY);
	case SSL_AD_UNEXPECTED_MESSAGE:
		return (SSL3_AD_UNEXPECTED_MESSAGE);
	case SSL_AD_BAD_RECORD_MAC:
		return (SSL3_AD_BAD_RECORD_MAC);
	case SSL_AD_DECRYPTION_FAILED:
		return (SSL3_AD_BAD_RECORD_MAC);
	case SSL_AD_RECORD_OVERFLOW:
		return (SSL3_AD_BAD_RECORD_MAC);
	case SSL_AD_DECOMPRESSION_FAILURE:
		return (SSL3_AD_DECOMPRESSION_FAILURE);
	case SSL_AD_HANDSHAKE_FAILURE:
		return (SSL3_AD_HANDSHAKE_FAILURE);
	case SSL_AD_NO_CERTIFICATE:
		return (SSL3_AD_NO_CERTIFICATE);
	case SSL_AD_BAD_CERTIFICATE:
		return (SSL3_AD_BAD_CERTIFICATE);
	case SSL_AD_UNSUPPORTED_CERTIFICATE:
		return (SSL3_AD_UNSUPPORTED_CERTIFICATE);
	case SSL_AD_CERTIFICATE_REVOKED:
		return (SSL3_AD_CERTIFICATE_REVOKED);
	case SSL_AD_CERTIFICATE_EXPIRED:
		return (SSL3_AD_CERTIFICATE_EXPIRED);
	case SSL_AD_CERTIFICATE_UNKNOWN:
		return (SSL3_AD_CERTIFICATE_UNKNOWN);
	case SSL_AD_ILLEGAL_PARAMETER:
		return (SSL3_AD_ILLEGAL_PARAMETER);
	case SSL_AD_UNKNOWN_CA:
		return (SSL3_AD_BAD_CERTIFICATE);
	case SSL_AD_ACCESS_DENIED:
		return (SSL3_AD_HANDSHAKE_FAILURE);
	case SSL_AD_DECODE_ERROR:
		return (SSL3_AD_HANDSHAKE_FAILURE);
	case SSL_AD_DECRYPT_ERROR:
		return (SSL3_AD_HANDSHAKE_FAILURE);
	case SSL_AD_EXPORT_RESTRICTION:
		return (SSL3_AD_HANDSHAKE_FAILURE);
	case SSL_AD_PROTOCOL_VERSION:
		return (SSL3_AD_HANDSHAKE_FAILURE);
	case SSL_AD_INSUFFICIENT_SECURITY:
		return (SSL3_AD_HANDSHAKE_FAILURE);
	case SSL_AD_INTERNAL_ERROR:
		return (SSL3_AD_HANDSHAKE_FAILURE);
	case SSL_AD_INAPPROPRIATE_FALLBACK:
		return (TLS1_AD_INAPPROPRIATE_FALLBACK);
	case SSL_AD_USER_CANCELLED:
		return (SSL3_AD_HANDSHAKE_FAILURE);
	case SSL_AD_NO_RENEGOTIATION:
		return(-1); /* Don't send it :-) */
	case SSL_AD_UNSUPPORTED_EXTENSION:
		return (SSL3_AD_HANDSHAKE_FAILURE);
	case SSL_AD_CERTIFICATE_UNOBTAINABLE:
		return (SSL3_AD_HANDSHAKE_FAILURE);
	case SSL_AD_UNRECOGNIZED_NAME:
		return (SSL3_AD_HANDSHAKE_FAILURE);
	case SSL_AD_BAD_CERTIFICATE_STATUS_RESPONSE:
		return (SSL3_AD_HANDSHAKE_FAILURE);
	case SSL_AD_BAD_CERTIFICATE_HASH_VALUE:
		return (SSL3_AD_HANDSHAKE_FAILURE);
	case SSL_AD_UNKNOWN_PSK_IDENTITY:
		return (TLS1_AD_UNKNOWN_PSK_IDENTITY);
	default:
		return (-1);
	}
}
