[thirdparty/openssl.git] / ssl / s3_enc.c

/* ssl/s3_enc.c */
/* 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 const 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 const 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;

#ifdef CHARSET_EBCDIC
        c = os_toascii[c]; /*'A' in ASCII */
#endif
        k=0;
        EVP_MD_CTX_init(&m5);
        EVP_MD_CTX_set_flags(&m5, EVP_MD_CTX_FLAG_NON_FIPS_ALLOW);
        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++;
                EVP_DigestInit_ex(&s1,EVP_sha1(), NULL);
                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);

                EVP_DigestInit_ex(&m5,EVP_md5(), NULL);
                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)
        {
        unsigned char *p,*mac_secret;
        unsigned char exp_key[EVP_MAX_KEY_LENGTH];
        unsigned char exp_iv[EVP_MAX_IV_LENGTH];
        unsigned char *ms,*key,*iv,*er1,*er2;
        EVP_CIPHER_CTX *dd;
        const EVP_CIPHER *c;
#ifndef OPENSSL_NO_COMP
        COMP_METHOD *comp;
#endif
        const EVP_MD *m;
        EVP_MD_CTX md;
        int is_exp,n,i,j,k,cl;
        int reuse_dd = 0;

        is_exp=SSL_C_IS_EXPORT(s->s3->tmp.new_cipher);
        c=s->s3->tmp.new_sym_enc;
        m=s->s3->tmp.new_hash;
        /* m == NULL will lead to a crash later */
        OPENSSL_assert(m);
#ifndef OPENSSL_NO_COMP
        if (s->s3->tmp.new_compression == NULL)
                comp=NULL;
        else
                comp=s->s3->tmp.new_compression->method;
#endif

        if (which & SSL3_CC_READ)
                {
                if (s->enc_read_ctx != NULL)
                        reuse_dd = 1;
                else if ((s->enc_read_ctx=OPENSSL_malloc(sizeof(EVP_CIPHER_CTX))) == NULL)
                        goto err;
                else
                        /* make sure it's intialized in case we exit later with an error */
                        EVP_CIPHER_CTX_init(s->enc_read_ctx);
                dd= s->enc_read_ctx;

                ssl_replace_hash(&s->read_hash,m);
#ifndef OPENSSL_NO_COMP
                /* COMPRESS */
                if (s->expand != NULL)
                        {
                        COMP_CTX_free(s->expand);
                        s->expand=NULL;
                        }
                if (comp != NULL)
                        {
                        s->expand=COMP_CTX_new(comp);
                        if (s->expand == NULL)
                                {
                                SSLerr(SSL_F_SSL3_CHANGE_CIPHER_STATE,SSL_R_COMPRESSION_LIBRARY_ERROR);
                                goto err2;
                                }
                        if (s->s3->rrec.comp == NULL)
                                s->s3->rrec.comp=(unsigned char *)
                                        OPENSSL_malloc(SSL3_RT_MAX_PLAIN_LENGTH);
                        if (s->s3->rrec.comp == NULL)
                                goto err;
                        }
#endif
                memset(&(s->s3->read_sequence[0]),0,8);
                mac_secret= &(s->s3->read_mac_secret[0]);
                }
        else
                {
                if (s->enc_write_ctx != NULL)
                        reuse_dd = 1;
                else if ((s->enc_write_ctx=OPENSSL_malloc(sizeof(EVP_CIPHER_CTX))) == NULL)
                        goto err;
                else
                        /* make sure it's intialized in case we exit later with an error */
                        EVP_CIPHER_CTX_init(s->enc_write_ctx);
                dd= s->enc_write_ctx;
                ssl_replace_hash(&s->write_hash,m);
#ifndef OPENSSL_NO_COMP
                /* COMPRESS */
                if (s->compress != NULL)
                        {
                        COMP_CTX_free(s->compress);
                        s->compress=NULL;
                        }
                if (comp != NULL)
                        {
                        s->compress=COMP_CTX_new(comp);
                        if (s->compress == NULL)
                                {
                                SSLerr(SSL_F_SSL3_CHANGE_CIPHER_STATE,SSL_R_COMPRESSION_LIBRARY_ERROR);
                                goto err2;
                                }
                        }
#endif
                memset(&(s->s3->write_sequence[0]),0,8);
                mac_secret= &(s->s3->write_mac_secret[0]);
                }

        if (reuse_dd)
                EVP_CIPHER_CTX_cleanup(dd);

        p=s->s3->tmp.key_block;
        i=EVP_MD_size(m);
        if (i < 0)
                goto err2;
        cl=EVP_CIPHER_key_length(c);
        j=is_exp ? (cl < SSL_C_EXPORT_KEYLENGTH(s->s3->tmp.new_cipher) ?
                 cl : SSL_C_EXPORT_KEYLENGTH(s->s3->tmp.new_cipher)) : cl;
        /* Was j=(is_exp)?5:EVP_CIPHER_key_length(c); */
        k=EVP_CIPHER_iv_length(c);
        if (    (which == SSL3_CHANGE_CIPHER_CLIENT_WRITE) ||
                (which == SSL3_CHANGE_CIPHER_SERVER_READ))
                {
                ms=  &(p[ 0]); n=i+i;
                key= &(p[ n]); n+=j+j;
                iv=  &(p[ n]); n+=k+k;
                er1= &(s->s3->client_random[0]);
                er2= &(s->s3->server_random[0]);
                }
        else
                {
                n=i;
                ms=  &(p[ n]); n+=i+j;
                key= &(p[ n]); n+=j+k;
                iv=  &(p[ n]); n+=k;
                er1= &(s->s3->server_random[0]);
                er2= &(s->s3->client_random[0]);
                }

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

        EVP_MD_CTX_init(&md);
        memcpy(mac_secret,ms,i);
        if (is_exp)
                {
                /* In here I set both the read and write key/iv to the
                 * same value since only the correct one will be used :-).
                 */
                EVP_DigestInit_ex(&md,EVP_md5(), NULL);
                EVP_DigestUpdate(&md,key,j);
                EVP_DigestUpdate(&md,er1,SSL3_RANDOM_SIZE);
                EVP_DigestUpdate(&md,er2,SSL3_RANDOM_SIZE);
                EVP_DigestFinal_ex(&md,&(exp_key[0]),NULL);
                key= &(exp_key[0]);

                if (k > 0)
                        {
                        EVP_DigestInit_ex(&md,EVP_md5(), NULL);
                        EVP_DigestUpdate(&md,er1,SSL3_RANDOM_SIZE);
                        EVP_DigestUpdate(&md,er2,SSL3_RANDOM_SIZE);
                        EVP_DigestFinal_ex(&md,&(exp_iv[0]),NULL);
                        iv= &(exp_iv[0]);
                        }
                }

        s->session->key_arg_length=0;

        EVP_CipherInit_ex(dd,c,NULL,key,iv,(which & SSL3_CC_WRITE));

#ifdef OPENSSL_SSL_TRACE_CRYPTO
        if (s->msg_callback)
                {
 
                int wh = which & SSL3_CC_WRITE ?
                                TLS1_RT_CRYPTO_WRITE : TLS1_RT_CRYPTO_READ;
                s->msg_callback(2, s->version, wh | TLS1_RT_CRYPTO_MAC,
                                                mac_secret, EVP_MD_size(m),
                                                s, s->msg_callback_arg);
                if (c->key_len)
                        s->msg_callback(2, s->version, wh | TLS1_RT_CRYPTO_KEY,
                                                key, c->key_len,
                                                s, s->msg_callback_arg);
                if (k)
                        {
                        s->msg_callback(2, s->version, wh | TLS1_RT_CRYPTO_IV,
                                                iv, k, s, s->msg_callback_arg);
                        }
                }
#endif

        OPENSSL_cleanse(&(exp_key[0]),sizeof(exp_key));
        OPENSSL_cleanse(&(exp_iv[0]),sizeof(exp_iv));
        EVP_MD_CTX_cleanup(&md);
        return(1);
err:
        SSLerr(SSL_F_SSL3_CHANGE_CIPHER_STATE,ERR_R_MALLOC_FAILURE);
err2:
        return(0);
        }

int ssl3_setup_key_block(SSL *s)
        {
        unsigned char *p;
        const EVP_CIPHER *c;
        const EVP_MD *hash;
        int num;
        int ret = 0;
        SSL_COMP *comp;

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

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

        s->s3->tmp.new_sym_enc=c;
        s->s3->tmp.new_hash=hash;
#ifdef OPENSSL_NO_COMP
        s->s3->tmp.new_compression=NULL;
#else
        s->s3->tmp.new_compression=comp;
#endif

        num=EVP_MD_size(hash);
        if (num < 0)
                return 0;

        num=EVP_CIPHER_key_length(c)+num+EVP_CIPHER_iv_length(c);
        num*=2;

        ssl3_cleanup_key_block(s);

        if ((p=OPENSSL_malloc(num)) == NULL)
                goto err;

        s->s3->tmp.key_block_length=num;
        s->s3->tmp.key_block=p;

        ret = ssl3_generate_key_block(s,p,num);

        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);
                OPENSSL_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
 *       occurred.
 */
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 */
                        }
                
                if(EVP_Cipher(ds,rec->data,rec->input,l) < 1)
                        return -1;

                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);
        }

void ssl3_init_finished_mac(SSL *s)
        {
        if (s->s3->handshake_buffer) BIO_free(s->s3->handshake_buffer);
        if (s->s3->handshake_dgst) ssl3_free_digest_list(s);
    s->s3->handshake_buffer=BIO_new(BIO_s_mem());       
        (void)BIO_set_close(s->s3->handshake_buffer,BIO_CLOSE);
        }

void ssl3_free_digest_list(SSL *s) 
        {
        int i;
        if (!s->s3->handshake_dgst) return;
        for (i=0;i<SSL_MAX_DIGEST;i++) 
                {
                if (s->s3->handshake_dgst[i])
                        EVP_MD_CTX_destroy(s->s3->handshake_dgst[i]);
                }
        OPENSSL_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;

        /* Allocate handshake_dgst array */
        ssl3_free_digest_list(s);
        s->s3->handshake_dgst = OPENSSL_malloc(SSL_MAX_DIGEST * sizeof(EVP_MD_CTX *));
        memset(s->s3->handshake_dgst,0,SSL_MAX_DIGEST *sizeof(EVP_MD_CTX *));
        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 bitso of algorithm2 field and create MD_CTX-es */
        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();
#ifdef OPENSSL_FIPS
                        if (EVP_MD_nid(md) == NID_md5)
                                {
                                EVP_MD_CTX_set_flags(s->s3->handshake_dgst[i],
                                                EVP_MD_CTX_FLAG_NON_FIPS_ALLOW);
                                }
#endif
                        EVP_DigestInit_ex(s->s3->handshake_dgst[i],md,NULL);
                        EVP_DigestUpdate(s->s3->handshake_dgst[i],hdata,hdatalen);
                        } 
                else 
                        {       
                        s->s3->handshake_dgst[i]=NULL;
                        }
                }
        if (!(s->s3->flags & TLS1_FLAGS_KEEP_HANDSHAKE))
                {
                /* Free handshake_buffer BIO */
                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, sha1len;
        ret=ssl3_handshake_mac(s,NID_md5,sender,len,p);
        if(ret == 0)
                return 0;

        p+=ret;

        sha1len=ssl3_handshake_mac(s,NID_sha1,sender,len,p);
        if(sha1len == 0)
                return 0;

        ret+=sha1len;
        return(ret);
        }
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);
        EVP_MD_CTX_set_flags(&ctx, EVP_MD_CTX_FLAG_NON_FIPS_ALLOW);
        EVP_MD_CTX_copy_ex(&ctx,d);
        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);

        EVP_DigestInit_ex(&ctx,EVP_MD_CTX_md(&ctx), NULL);
        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;
        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;

        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;

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

                EVP_MD_CTX_copy_ex( &md_ctx,hash);
                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);

                EVP_MD_CTX_copy_ex( &md_ctx,hash);
                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_update(seq);
        return(md_size);
        }

void ssl3_record_sequence_update(unsigned char *seq)
        {
        int i;

        for (i=7; i>=0; i--)
                {
                ++seq[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]={
#ifndef CHARSET_EBCDIC
                (const unsigned char *)"A",
                (const unsigned char *)"BB",
                (const unsigned char *)"CCC",
#else
                (const unsigned char *)"\x41",
                (const unsigned char *)"\x42\x42",
                (const unsigned char *)"\x43\x43\x43",
#endif
                };
        unsigned char buf[EVP_MAX_MD_SIZE];
        EVP_MD_CTX ctx;
        int i,ret=0;
        unsigned int n;
#ifdef OPENSSL_SSL_TRACE_CRYPTO
        unsigned char *tmpout = out;
#endif

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

                EVP_DigestInit_ex(&ctx,s->ctx->md5, NULL);
                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);

#ifdef OPENSSL_SSL_TRACE_CRYPTO
        if (s->msg_callback)
                {
                s->msg_callback(2, s->version, TLS1_RT_CRYPTO_PREMASTER,
                                                p, len, s, s->msg_callback_arg);
                s->msg_callback(2, s->version, TLS1_RT_CRYPTO_CLIENT_RANDOM,
                                        s->s3->client_random, SSL3_RANDOM_SIZE,
                                                s, s->msg_callback_arg);
                s->msg_callback(2, s->version, TLS1_RT_CRYPTO_SERVER_RANDOM,
                                        s->s3->server_random, SSL3_RANDOM_SIZE,
                                        s, s->msg_callback_arg);
                s->msg_callback(2, s->version, TLS1_RT_CRYPTO_MASTER,
                                        tmpout, SSL3_MASTER_SECRET_SIZE,
                                        s, s->msg_callback_arg);
                }
#endif
        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_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);
        case SSL_AD_INAPPROPRIATE_FALLBACK:return(TLS1_AD_INAPPROPRIATE_FALLBACK);
        default:                        return(-1);
                }
        }