s3_both.c

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/* ssl/s3_both.c */
/* Copyright (C) 1995-1998 Eric Young ([email protected])
 * All rights reserved.
 *
 * This package is an SSL implementation written
 * by Eric Young ([email protected]).
 * 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 ([email protected]).
 * 
 * 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 ([email protected])"
 *    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 ([email protected])"
 * 
 * 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) 1998-2002 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
 *    [email protected].
 *
 * 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
 * ([email protected]).  This product includes software written by Tim
 * Hudson ([email protected]).
 *
 */
/* ====================================================================
 * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
 * ECC cipher suite support in OpenSSL originally developed by 
 * SUN MICROSYSTEMS, INC., and contributed to the OpenSSL project.
 */

#include <limits.h>
#include <string.h>
#include <stdio.h>
#include "ssl_locl.h"
#include <openssl/buffer.h>
#include <openssl/rand.h>
#include <openssl/objects.h>
#include <openssl/evp.h>
#include <openssl/x509.h>

/* send s->init_buf in records of type 'type' (SSL3_RT_HANDSHAKE or SSL3_RT_CHANGE_CIPHER_SPEC) */
int ssl3_do_write(SSL *s, int type)
    {
    int ret;

    ret=ssl3_write_bytes(s,type,&s->init_buf->data[s->init_off],
                         s->init_num);
    if (ret < 0) return(-1);
    if (type == SSL3_RT_HANDSHAKE)
        /* should not be done for 'Hello Request's, but in that case
         * we'll ignore the result anyway */
        ssl3_finish_mac(s,(unsigned char *)&s->init_buf->data[s->init_off],ret);
    
    if (ret == s->init_num)
        {
        if (s->msg_callback)
            s->msg_callback(1, s->version, type, s->init_buf->data, (size_t)(s->init_off + s->init_num), s, s->msg_callback_arg);
        return(1);
        }
    s->init_off+=ret;
    s->init_num-=ret;
    return(0);
    }

int ssl3_send_finished(SSL *s, int a, int b, const char *sender, int slen)
    {
    unsigned char *p,*d;
    int i;
    unsigned long l;

    if (s->state == a)
        {
        d=(unsigned char *)s->init_buf->data;
        p= &(d[4]);

        i=s->method->ssl3_enc->final_finish_mac(s,
            sender,slen,s->s3->tmp.finish_md);
        s->s3->tmp.finish_md_len = i;
        memcpy(p, s->s3->tmp.finish_md, i);
        p+=i;
        l=i;

                /* Copy the finished so we can use it for
                   renegotiation checks */
                if(s->type == SSL_ST_CONNECT)
                        {
                         OPENSSL_assert(i <= EVP_MAX_MD_SIZE);
                         memcpy(s->s3->previous_client_finished, 
                             s->s3->tmp.finish_md, i);
                         s->s3->previous_client_finished_len=i;
                        }
                else
                        {
                        OPENSSL_assert(i <= EVP_MAX_MD_SIZE);
                        memcpy(s->s3->previous_server_finished, 
                            s->s3->tmp.finish_md, i);
                        s->s3->previous_server_finished_len=i;
                        }

#ifdef OPENSSL_SYS_WIN16
        /* MSVC 1.5 does not clear the top bytes of the word unless
         * I do this.
         */
        l&=0xffff;
#endif

        *(d++)=SSL3_MT_FINISHED;
        l2n3(l,d);
        s->init_num=(int)l+4;
        s->init_off=0;

        s->state=b;
        }

    /* SSL3_ST_SEND_xxxxxx_HELLO_B */
    return(ssl3_do_write(s,SSL3_RT_HANDSHAKE));
    }

#ifndef OPENSSL_NO_NEXTPROTONEG
/* ssl3_take_mac calculates the Finished MAC for the handshakes messages seen to far. */
static void ssl3_take_mac(SSL *s) {
    const char *sender;
    int slen;

    if (s->state & SSL_ST_CONNECT)
        {
        sender=s->method->ssl3_enc->server_finished_label;
        slen=s->method->ssl3_enc->server_finished_label_len;
        }
    else
        {
        sender=s->method->ssl3_enc->client_finished_label;
        slen=s->method->ssl3_enc->client_finished_label_len;
        }

    s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
        sender,slen,s->s3->tmp.peer_finish_md);
}
#endif

int ssl3_get_finished(SSL *s, int a, int b)
    {
    int al,i,ok;
    long n;
    unsigned char *p;

#ifdef OPENSSL_NO_NEXTPROTONEG
    /* the mac has already been generated when we received the change
     * cipher spec message and is in s->s3->tmp.peer_finish_md. */
#endif

    n=s->method->ssl_get_message(s,
        a,
        b,
        SSL3_MT_FINISHED,
        64, /* should actually be 36+4 :-) */
        &ok);

    if (!ok) return((int)n);

    /* If this occurs, we have missed a message */
    if (!s->s3->change_cipher_spec)
        {
        al=SSL_AD_UNEXPECTED_MESSAGE;
        SSLerr(SSL_F_SSL3_GET_FINISHED,SSL_R_GOT_A_FIN_BEFORE_A_CCS);
        goto f_err;
        }
    s->s3->change_cipher_spec=0;

    p = (unsigned char *)s->init_msg;
    i = s->s3->tmp.peer_finish_md_len;

    if (i != n)
        {
        al=SSL_AD_DECODE_ERROR;
        SSLerr(SSL_F_SSL3_GET_FINISHED,SSL_R_BAD_DIGEST_LENGTH);
        goto f_err;
        }

    if (memcmp(p, s->s3->tmp.peer_finish_md, i) != 0)
        {
        al=SSL_AD_DECRYPT_ERROR;
        SSLerr(SSL_F_SSL3_GET_FINISHED,SSL_R_DIGEST_CHECK_FAILED);
        goto f_err;
        }

        /* Copy the finished so we can use it for
           renegotiation checks */
        if(s->type == SSL_ST_ACCEPT)
                {
                OPENSSL_assert(i <= EVP_MAX_MD_SIZE);
                memcpy(s->s3->previous_client_finished, 
                    s->s3->tmp.peer_finish_md, i);
                s->s3->previous_client_finished_len=i;
                }
        else
                {
                OPENSSL_assert(i <= EVP_MAX_MD_SIZE);
                memcpy(s->s3->previous_server_finished, 
                    s->s3->tmp.peer_finish_md, i);
                s->s3->previous_server_finished_len=i;
                }

    return(1);
f_err:
    ssl3_send_alert(s,SSL3_AL_FATAL,al);
    return(0);
    }

/* for these 2 messages, we need to
 * ssl->enc_read_ctx            re-init
 * ssl->s3->read_sequence       zero
 * ssl->s3->read_mac_secret     re-init
 * ssl->session->read_sym_enc       assign
 * ssl->session->read_compression   assign
 * ssl->session->read_hash      assign
 */
int ssl3_send_change_cipher_spec(SSL *s, int a, int b)
    { 
    unsigned char *p;

    if (s->state == a)
        {
        p=(unsigned char *)s->init_buf->data;
        *p=SSL3_MT_CCS;
        s->init_num=1;
        s->init_off=0;

        s->state=b;
        }

    /* SSL3_ST_CW_CHANGE_B */
    return(ssl3_do_write(s,SSL3_RT_CHANGE_CIPHER_SPEC));
    }

static int ssl3_add_cert_to_buf(BUF_MEM *buf, unsigned long *l, X509 *x)
    {
    int n;
    unsigned char *p;

    n=i2d_X509(x,NULL);
    if (!BUF_MEM_grow_clean(buf,(int)(n+(*l)+3)))
        {
        SSLerr(SSL_F_SSL3_ADD_CERT_TO_BUF,ERR_R_BUF_LIB);
        return(-1);
        }
    p=(unsigned char *)&(buf->data[*l]);
    l2n3(n,p);
    i2d_X509(x,&p);
    *l+=n+3;

    return(0);
    }

unsigned long ssl3_output_cert_chain(SSL *s, X509 *x)
    {
    unsigned char *p;
    int i;
    unsigned long l=7;
    BUF_MEM *buf;
    int no_chain;

    if ((s->mode & SSL_MODE_NO_AUTO_CHAIN) || s->ctx->extra_certs)
        no_chain = 1;
    else
        no_chain = 0;

    /* TLSv1 sends a chain with nothing in it, instead of an alert */
    buf=s->init_buf;
    if (!BUF_MEM_grow_clean(buf,10))
        {
        SSLerr(SSL_F_SSL3_OUTPUT_CERT_CHAIN,ERR_R_BUF_LIB);
        return(0);
        }
    if (x != NULL)
        {
        if (no_chain)
            {
            if (ssl3_add_cert_to_buf(buf, &l, x))
                return(0);
            }
        else
            {
            X509_STORE_CTX xs_ctx;

            if (!X509_STORE_CTX_init(&xs_ctx,s->ctx->cert_store,x,NULL))
                {
                SSLerr(SSL_F_SSL3_OUTPUT_CERT_CHAIN,ERR_R_X509_LIB);
                return(0);
                }
            X509_verify_cert(&xs_ctx);
            /* Don't leave errors in the queue */
            ERR_clear_error();
            for (i=0; i < sk_X509_num(xs_ctx.chain); i++)
                {
                x = sk_X509_value(xs_ctx.chain, i);

                if (ssl3_add_cert_to_buf(buf, &l, x))
                    {
                    X509_STORE_CTX_cleanup(&xs_ctx);
                    return 0;
                    }
                }
            X509_STORE_CTX_cleanup(&xs_ctx);
            }
        }
    /* Thawte special :-) */
    for (i=0; i<sk_X509_num(s->ctx->extra_certs); i++)
        {
        x=sk_X509_value(s->ctx->extra_certs,i);
        if (ssl3_add_cert_to_buf(buf, &l, x))
            return(0);
        }

    l-=7;
    p=(unsigned char *)&(buf->data[4]);
    l2n3(l,p);
    l+=3;
    p=(unsigned char *)&(buf->data[0]);
    *(p++)=SSL3_MT_CERTIFICATE;
    l2n3(l,p);
    l+=4;
    return(l);
    }

/* Obtain handshake message of message type 'mt' (any if mt == -1),
 * maximum acceptable body length 'max'.
 * The first four bytes (msg_type and length) are read in state 'st1',
 * the body is read in state 'stn'.
 */
long ssl3_get_message(SSL *s, int st1, int stn, int mt, long max, int *ok)
    {
    unsigned char *p;
    unsigned long l;
    long n;
    int i,al;

    if (s->s3->tmp.reuse_message)
        {
        s->s3->tmp.reuse_message=0;
        if ((mt >= 0) && (s->s3->tmp.message_type != mt))
            {
            al=SSL_AD_UNEXPECTED_MESSAGE;
            SSLerr(SSL_F_SSL3_GET_MESSAGE,SSL_R_UNEXPECTED_MESSAGE);
            goto f_err;
            }
        *ok=1;
        s->init_msg = s->init_buf->data + 4;
        s->init_num = (int)s->s3->tmp.message_size;
        return s->init_num;
        }

    p=(unsigned char *)s->init_buf->data;

    if (s->state == st1) /* s->init_num < 4 */
        {
        int skip_message;

        do
            {
            while (s->init_num < 4)
                {
                i=s->method->ssl_read_bytes(s,SSL3_RT_HANDSHAKE,
                    &p[s->init_num],4 - s->init_num, 0);
                if (i <= 0)
                    {
                    s->rwstate=SSL_READING;
                    *ok = 0;
                    return i;
                    }
                s->init_num+=i;
                }
            
            skip_message = 0;
            if (!s->server)
                if (p[0] == SSL3_MT_HELLO_REQUEST)
                    /* The server may always send 'Hello Request' messages --
                     * we are doing a handshake anyway now, so ignore them
                     * if their format is correct. Does not count for
                     * 'Finished' MAC. */
                    if (p[1] == 0 && p[2] == 0 &&p[3] == 0)
                        {
                        s->init_num = 0;
                        skip_message = 1;

                        if (s->msg_callback)
                            s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, p, 4, s, s->msg_callback_arg);
                        }
            }
        while (skip_message);

        /* s->init_num == 4 */

        if ((mt >= 0) && (*p != mt))
            {
            al=SSL_AD_UNEXPECTED_MESSAGE;
            SSLerr(SSL_F_SSL3_GET_MESSAGE,SSL_R_UNEXPECTED_MESSAGE);
            goto f_err;
            }
        if ((mt < 0) && (*p == SSL3_MT_CLIENT_HELLO) &&
                    (st1 == SSL3_ST_SR_CERT_A) &&
                    (stn == SSL3_ST_SR_CERT_B))
            {
            /* At this point we have got an MS SGC second client
             * hello (maybe we should always allow the client to
             * start a new handshake?). We need to restart the mac.
             * Don't increment {num,total}_renegotiations because
             * we have not completed the handshake. */
            ssl3_init_finished_mac(s);
            }

        s->s3->tmp.message_type= *(p++);

        n2l3(p,l);
        if (l > (unsigned long)max)
            {
            al=SSL_AD_ILLEGAL_PARAMETER;
            SSLerr(SSL_F_SSL3_GET_MESSAGE,SSL_R_EXCESSIVE_MESSAGE_SIZE);
            goto f_err;
            }
        if (l > (INT_MAX-4)) /* BUF_MEM_grow takes an 'int' parameter */
            {
            al=SSL_AD_ILLEGAL_PARAMETER;
            SSLerr(SSL_F_SSL3_GET_MESSAGE,SSL_R_EXCESSIVE_MESSAGE_SIZE);
            goto f_err;
            }
        if (l && !BUF_MEM_grow_clean(s->init_buf,(int)l+4))
            {
            SSLerr(SSL_F_SSL3_GET_MESSAGE,ERR_R_BUF_LIB);
            goto err;
            }
        s->s3->tmp.message_size=l;
        s->state=stn;

        s->init_msg = s->init_buf->data + 4;
        s->init_num = 0;
        }

    /* next state (stn) */
    p = s->init_msg;
    n = s->s3->tmp.message_size - s->init_num;
    while (n > 0)
        {
        i=s->method->ssl_read_bytes(s,SSL3_RT_HANDSHAKE,&p[s->init_num],n,0);
        if (i <= 0)
            {
            s->rwstate=SSL_READING;
            *ok = 0;
            return i;
            }
        s->init_num += i;
        n -= i;
        }
#ifndef OPENSSL_NO_NEXTPROTONEG
    /* If receiving Finished, record MAC of prior handshake messages for
     * Finished verification. */
    if (*s->init_buf->data == SSL3_MT_FINISHED)
        ssl3_take_mac(s);
#endif
    /* Feed this message into MAC computation. */
    ssl3_finish_mac(s, (unsigned char *)s->init_buf->data, s->init_num + 4);
    if (s->msg_callback)
        s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->init_buf->data, (size_t)s->init_num + 4, s, s->msg_callback_arg);
    *ok=1;
    return s->init_num;
f_err:
    ssl3_send_alert(s,SSL3_AL_FATAL,al);
err:
    *ok=0;
    return(-1);
    }

int ssl_cert_type(X509 *x, EVP_PKEY *pkey)
    {
    EVP_PKEY *pk;
    int ret= -1,i;

    if (pkey == NULL)
        pk=X509_get_pubkey(x);
    else
        pk=pkey;
    if (pk == NULL) goto err;

    i=pk->type;
    if (i == EVP_PKEY_RSA)
        {
        ret=SSL_PKEY_RSA_ENC;
        }
    else if (i == EVP_PKEY_DSA)
        {
        ret=SSL_PKEY_DSA_SIGN;
        }
#ifndef OPENSSL_NO_EC
    else if (i == EVP_PKEY_EC)
        {
        ret = SSL_PKEY_ECC;
        }   
#endif
    else if (i == NID_id_GostR3410_94 || i == NID_id_GostR3410_94_cc) 
        {
        ret = SSL_PKEY_GOST94;
        }
    else if (i == NID_id_GostR3410_2001 || i == NID_id_GostR3410_2001_cc) 
        {
        ret = SSL_PKEY_GOST01;
        }
err:
    if(!pkey) EVP_PKEY_free(pk);
    return(ret);
    }

int ssl_verify_alarm_type(long type)
    {
    int al;

    switch(type)
        {
    case X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT:
    case X509_V_ERR_UNABLE_TO_GET_CRL:
    case X509_V_ERR_UNABLE_TO_GET_CRL_ISSUER:
        al=SSL_AD_UNKNOWN_CA;
        break;
    case X509_V_ERR_UNABLE_TO_DECRYPT_CERT_SIGNATURE:
    case X509_V_ERR_UNABLE_TO_DECRYPT_CRL_SIGNATURE:
    case X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY:
    case X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD:
    case X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD:
    case X509_V_ERR_ERROR_IN_CRL_LAST_UPDATE_FIELD:
    case X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD:
    case X509_V_ERR_CERT_NOT_YET_VALID:
    case X509_V_ERR_CRL_NOT_YET_VALID:
    case X509_V_ERR_CERT_UNTRUSTED:
    case X509_V_ERR_CERT_REJECTED:
        al=SSL_AD_BAD_CERTIFICATE;
        break;
    case X509_V_ERR_CERT_SIGNATURE_FAILURE:
    case X509_V_ERR_CRL_SIGNATURE_FAILURE:
        al=SSL_AD_DECRYPT_ERROR;
        break;
    case X509_V_ERR_CERT_HAS_EXPIRED:
    case X509_V_ERR_CRL_HAS_EXPIRED:
        al=SSL_AD_CERTIFICATE_EXPIRED;
        break;
    case X509_V_ERR_CERT_REVOKED:
        al=SSL_AD_CERTIFICATE_REVOKED;
        break;
    case X509_V_ERR_OUT_OF_MEM:
        al=SSL_AD_INTERNAL_ERROR;
        break;
    case X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT:
    case X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN:
    case X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY:
    case X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE:
    case X509_V_ERR_CERT_CHAIN_TOO_LONG:
    case X509_V_ERR_PATH_LENGTH_EXCEEDED:
    case X509_V_ERR_INVALID_CA:
        al=SSL_AD_UNKNOWN_CA;
        break;
    case X509_V_ERR_APPLICATION_VERIFICATION:
        al=SSL_AD_HANDSHAKE_FAILURE;
        break;
    case X509_V_ERR_INVALID_PURPOSE:
        al=SSL_AD_UNSUPPORTED_CERTIFICATE;
        break;
    default:
        al=SSL_AD_CERTIFICATE_UNKNOWN;
        break;
        }
    return(al);
    }

#ifndef OPENSSL_NO_BUF_FREELISTS
/* On some platforms, malloc() performance is bad enough that you can't just
 * free() and malloc() buffers all the time, so we need to use freelists from
 * unused buffers.  Currently, each freelist holds memory chunks of only a
 * given size (list->chunklen); other sized chunks are freed and malloced.
 * This doesn't help much if you're using many different SSL option settings
 * with a given context.  (The options affecting buffer size are
 * max_send_fragment, read buffer vs write buffer,
 * SSL_OP_MICROSOFT_BIG_WRITE_BUFFER, SSL_OP_NO_COMPRESSION, and
 * SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS.)  Using a separate freelist for every
 * possible size is not an option, since max_send_fragment can take on many
 * different values.
 *
 * If you are on a platform with a slow malloc(), and you're using SSL
 * connections with many different settings for these options, and you need to
 * use the SSL_MOD_RELEASE_BUFFERS feature, you have a few options:
 *    - Link against a faster malloc implementation.
 *    - Use a separate SSL_CTX for each option set.
 *    - Improve this code.
 */
static void *
freelist_extract(SSL_CTX *ctx, int for_read, int sz)
    {
    SSL3_BUF_FREELIST *list;
    SSL3_BUF_FREELIST_ENTRY *ent = NULL;
    void *result = NULL;

    CRYPTO_w_lock(CRYPTO_LOCK_SSL_CTX);
    list = for_read ? ctx->rbuf_freelist : ctx->wbuf_freelist;
    if (list != NULL && sz == (int)list->chunklen)
        ent = list->head;
    if (ent != NULL)
        {
        list->head = ent->next;
        result = ent;
        if (--list->len == 0)
            list->chunklen = 0;
        }
    CRYPTO_w_unlock(CRYPTO_LOCK_SSL_CTX);
    if (!result)
        result = OPENSSL_malloc(sz);
    return result;
}

static void
freelist_insert(SSL_CTX *ctx, int for_read, size_t sz, void *mem)
    {
    SSL3_BUF_FREELIST *list;
    SSL3_BUF_FREELIST_ENTRY *ent;

    CRYPTO_w_lock(CRYPTO_LOCK_SSL_CTX);
    list = for_read ? ctx->rbuf_freelist : ctx->wbuf_freelist;
    if (list != NULL &&
        (sz == list->chunklen || list->chunklen == 0) &&
        list->len < ctx->freelist_max_len &&
        sz >= sizeof(*ent))
        {
        list->chunklen = sz;
        ent = mem;
        ent->next = list->head;
        list->head = ent;
        ++list->len;
        mem = NULL;
        }

    CRYPTO_w_unlock(CRYPTO_LOCK_SSL_CTX);
    if (mem)
        OPENSSL_free(mem);
    }
#else
#define freelist_extract(c,fr,sz) OPENSSL_malloc(sz)
#define freelist_insert(c,fr,sz,m) OPENSSL_free(m)
#endif

int ssl3_setup_read_buffer(SSL *s)
    {
    unsigned char *p;
    size_t len,align=0,headerlen;
    
    if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER)
        headerlen = DTLS1_RT_HEADER_LENGTH;
    else
        headerlen = SSL3_RT_HEADER_LENGTH;

#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
    align = (-SSL3_RT_HEADER_LENGTH)&(SSL3_ALIGN_PAYLOAD-1);
#endif

    if (s->s3->rbuf.buf == NULL)
        {
        len = SSL3_RT_MAX_PLAIN_LENGTH
            + SSL3_RT_MAX_ENCRYPTED_OVERHEAD
            + headerlen + align;
        if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
            {
            s->s3->init_extra = 1;
            len += SSL3_RT_MAX_EXTRA;
            }
#ifndef OPENSSL_NO_COMP
        if (!(s->options & SSL_OP_NO_COMPRESSION))
            len += SSL3_RT_MAX_COMPRESSED_OVERHEAD;
#endif
        if ((p=freelist_extract(s->ctx, 1, len)) == NULL)
            goto err;
        s->s3->rbuf.buf = p;
        s->s3->rbuf.len = len;
        }

    s->packet= &(s->s3->rbuf.buf[0]);
    return 1;

err:
    SSLerr(SSL_F_SSL3_SETUP_READ_BUFFER,ERR_R_MALLOC_FAILURE);
    return 0;
    }

int ssl3_setup_write_buffer(SSL *s)
    {
    unsigned char *p;
    size_t len,align=0,headerlen;

    if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER)
        headerlen = DTLS1_RT_HEADER_LENGTH + 1;
    else
        headerlen = SSL3_RT_HEADER_LENGTH;

#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
    align = (-SSL3_RT_HEADER_LENGTH)&(SSL3_ALIGN_PAYLOAD-1);
#endif

    if (s->s3->wbuf.buf == NULL)
        {
        len = s->max_send_fragment
            + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD
            + headerlen + align;
#ifndef OPENSSL_NO_COMP
        if (!(s->options & SSL_OP_NO_COMPRESSION))
            len += SSL3_RT_MAX_COMPRESSED_OVERHEAD;
#endif
        if (!(s->options & SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS))
            len += headerlen + align
                + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD;

        if ((p=freelist_extract(s->ctx, 0, len)) == NULL)
            goto err;
        s->s3->wbuf.buf = p;
        s->s3->wbuf.len = len;
        }

    return 1;

err:
    SSLerr(SSL_F_SSL3_SETUP_WRITE_BUFFER,ERR_R_MALLOC_FAILURE);
    return 0;
    }


int ssl3_setup_buffers(SSL *s)
    {
    if (!ssl3_setup_read_buffer(s))
        return 0;
    if (!ssl3_setup_write_buffer(s))
        return 0;
    return 1;
    }

int ssl3_release_write_buffer(SSL *s)
    {
    if (s->s3->wbuf.buf != NULL)
        {
        freelist_insert(s->ctx, 0, s->s3->wbuf.len, s->s3->wbuf.buf);
        s->s3->wbuf.buf = NULL;
        }
    return 1;
    }

int ssl3_release_read_buffer(SSL *s)
    {
    if (s->s3->rbuf.buf != NULL)
        {
        freelist_insert(s->ctx, 1, s->s3->rbuf.len, s->s3->rbuf.buf);
        s->s3->rbuf.buf = NULL;
        }
    return 1;
    }