freebsd-nq/crypto/openssl/ssl/s2_clnt.c

/* ssl/s2_clnt.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) 1998-2001 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).
 *
 */

#include "ssl_locl.h"
#ifndef OPENSSL_NO_SSL2
# include <stdio.h>
# include <openssl/rand.h>
# include <openssl/buffer.h>
# include <openssl/objects.h>
# include <openssl/evp.h>

static const SSL_METHOD *ssl2_get_client_method(int ver);
static int get_server_finished(SSL *s);
static int get_server_verify(SSL *s);
static int get_server_hello(SSL *s);
static int client_hello(SSL *s);
static int client_master_key(SSL *s);
static int client_finished(SSL *s);
static int client_certificate(SSL *s);
static int ssl_rsa_public_encrypt(SESS_CERT *sc, int len, unsigned char *from,
                                  unsigned char *to, int padding);
# define BREAK   break

static const SSL_METHOD *ssl2_get_client_method(int ver)
{
    if (ver == SSL2_VERSION)
        return (SSLv2_client_method());
    else
        return (NULL);
}

IMPLEMENT_ssl2_meth_func(SSLv2_client_method,
                         ssl_undefined_function,
                         ssl2_connect, ssl2_get_client_method)

int ssl2_connect(SSL *s)
{
    unsigned long l = (unsigned long)time(NULL);
    BUF_MEM *buf = NULL;
    int ret = -1;
    void (*cb) (const SSL *ssl, int type, int val) = NULL;
    int new_state, state;

    RAND_add(&l, sizeof(l), 0);
    ERR_clear_error();
    clear_sys_error();

    if (s->info_callback != NULL)
        cb = s->info_callback;
    else if (s->ctx->info_callback != NULL)
        cb = s->ctx->info_callback;

    /* init things to blank */
    s->in_handshake++;
    if (!SSL_in_init(s) || SSL_in_before(s))
        SSL_clear(s);

    for (;;) {
        state = s->state;

        switch (s->state) {
        case SSL_ST_BEFORE:
        case SSL_ST_CONNECT:
        case SSL_ST_BEFORE | SSL_ST_CONNECT:
        case SSL_ST_OK | SSL_ST_CONNECT:

            s->server = 0;
            if (cb != NULL)
                cb(s, SSL_CB_HANDSHAKE_START, 1);

            s->version = SSL2_VERSION;
            s->type = SSL_ST_CONNECT;

            buf = s->init_buf;
            if ((buf == NULL) && ((buf = BUF_MEM_new()) == NULL)) {
                ret = -1;
                goto end;
            }
            if (!BUF_MEM_grow(buf, SSL2_MAX_RECORD_LENGTH_3_BYTE_HEADER)) {
                if (buf == s->init_buf)
                    buf = NULL;
                ret = -1;
                goto end;
            }
            s->init_buf = buf;
            buf = NULL;
            s->init_num = 0;
            s->state = SSL2_ST_SEND_CLIENT_HELLO_A;
            s->ctx->stats.sess_connect++;
            s->handshake_func = ssl2_connect;
            BREAK;

        case SSL2_ST_SEND_CLIENT_HELLO_A:
        case SSL2_ST_SEND_CLIENT_HELLO_B:
            s->shutdown = 0;
            ret = client_hello(s);
            if (ret <= 0)
                goto end;
            s->init_num = 0;
            s->state = SSL2_ST_GET_SERVER_HELLO_A;
            BREAK;

        case SSL2_ST_GET_SERVER_HELLO_A:
        case SSL2_ST_GET_SERVER_HELLO_B:
            ret = get_server_hello(s);
            if (ret <= 0)
                goto end;
            s->init_num = 0;
            if (!s->hit) {      /* new session */
                s->state = SSL2_ST_SEND_CLIENT_MASTER_KEY_A;
                BREAK;
            } else {
                s->state = SSL2_ST_CLIENT_START_ENCRYPTION;
                break;
            }

        case SSL2_ST_SEND_CLIENT_MASTER_KEY_A:
        case SSL2_ST_SEND_CLIENT_MASTER_KEY_B:
            ret = client_master_key(s);
            if (ret <= 0)
                goto end;
            s->init_num = 0;
            s->state = SSL2_ST_CLIENT_START_ENCRYPTION;
            break;

        case SSL2_ST_CLIENT_START_ENCRYPTION:
            /*
             * Ok, we now have all the stuff needed to start encrypting, so
             * lets fire it up :-)
             */
            if (!ssl2_enc_init(s, 1)) {
                ret = -1;
                goto end;
            }
            s->s2->clear_text = 0;
            s->state = SSL2_ST_SEND_CLIENT_FINISHED_A;
            break;

        case SSL2_ST_SEND_CLIENT_FINISHED_A:
        case SSL2_ST_SEND_CLIENT_FINISHED_B:
            ret = client_finished(s);
            if (ret <= 0)
                goto end;
            s->init_num = 0;
            s->state = SSL2_ST_GET_SERVER_VERIFY_A;
            break;

        case SSL2_ST_GET_SERVER_VERIFY_A:
        case SSL2_ST_GET_SERVER_VERIFY_B:
            ret = get_server_verify(s);
            if (ret <= 0)
                goto end;
            s->init_num = 0;
            s->state = SSL2_ST_GET_SERVER_FINISHED_A;
            break;

        case SSL2_ST_GET_SERVER_FINISHED_A:
        case SSL2_ST_GET_SERVER_FINISHED_B:
            ret = get_server_finished(s);
            if (ret <= 0)
                goto end;
            break;

        case SSL2_ST_SEND_CLIENT_CERTIFICATE_A:
        case SSL2_ST_SEND_CLIENT_CERTIFICATE_B:
        case SSL2_ST_SEND_CLIENT_CERTIFICATE_C:
        case SSL2_ST_SEND_CLIENT_CERTIFICATE_D:
        case SSL2_ST_X509_GET_CLIENT_CERTIFICATE:
            ret = client_certificate(s);
            if (ret <= 0)
                goto end;
            s->init_num = 0;
            s->state = SSL2_ST_GET_SERVER_FINISHED_A;
            break;

        case SSL_ST_OK:
            if (s->init_buf != NULL) {
                BUF_MEM_free(s->init_buf);
                s->init_buf = NULL;
            }
            s->init_num = 0;
            /*      ERR_clear_error(); */

            /*
             * If we want to cache session-ids in the client and we
             * successfully add the session-id to the cache, and there is a
             * callback, then pass it out. 26/11/96 - eay - only add if not a
             * re-used session.
             */

            ssl_update_cache(s, SSL_SESS_CACHE_CLIENT);
            if (s->hit)
                s->ctx->stats.sess_hit++;

            ret = 1;
            /* s->server=0; */
            s->ctx->stats.sess_connect_good++;

            if (cb != NULL)
                cb(s, SSL_CB_HANDSHAKE_DONE, 1);

            goto end;
            /* break; */
        default:
            SSLerr(SSL_F_SSL2_CONNECT, SSL_R_UNKNOWN_STATE);
            return (-1);
            /* break; */
        }

        if ((cb != NULL) && (s->state != state)) {
            new_state = s->state;
            s->state = state;
            cb(s, SSL_CB_CONNECT_LOOP, 1);
            s->state = new_state;
        }
    }
 end:
    s->in_handshake--;
    if (buf != NULL)
        BUF_MEM_free(buf);
    if (cb != NULL)
        cb(s, SSL_CB_CONNECT_EXIT, ret);
    return (ret);
}

static int get_server_hello(SSL *s)
{
    unsigned char *buf;
    unsigned char *p;
    int i, j;
    unsigned long len;
    STACK_OF(SSL_CIPHER) *sk = NULL, *cl, *prio, *allow;

    buf = (unsigned char *)s->init_buf->data;
    p = buf;
    if (s->state == SSL2_ST_GET_SERVER_HELLO_A) {
        i = ssl2_read(s, (char *)&(buf[s->init_num]), 11 - s->init_num);
        if (i < (11 - s->init_num))
            return (ssl2_part_read(s, SSL_F_GET_SERVER_HELLO, i));
        s->init_num = 11;

        if (*(p++) != SSL2_MT_SERVER_HELLO) {
            if (p[-1] != SSL2_MT_ERROR) {
                ssl2_return_error(s, SSL2_PE_UNDEFINED_ERROR);
                SSLerr(SSL_F_GET_SERVER_HELLO, SSL_R_READ_WRONG_PACKET_TYPE);
            } else
                SSLerr(SSL_F_GET_SERVER_HELLO, SSL_R_PEER_ERROR);
            return (-1);
        }
# if 0
        s->hit = (*(p++)) ? 1 : 0;
        /*
         * Some [PPC?] compilers fail to increment p in above statement, e.g.
         * one provided with Rhapsody 5.5, but most recent example XL C 11.1
         * for AIX, even without optimization flag...
         */
# else
        s->hit = (*p) ? 1 : 0;
        p++;
# endif
        s->s2->tmp.cert_type = *(p++);
        n2s(p, i);
        if (i < s->version)
            s->version = i;
        n2s(p, i);
        s->s2->tmp.cert_length = i;
        n2s(p, i);
        s->s2->tmp.csl = i;
        n2s(p, i);
        s->s2->tmp.conn_id_length = i;
        s->state = SSL2_ST_GET_SERVER_HELLO_B;
    }

    /* SSL2_ST_GET_SERVER_HELLO_B */
    len =
        11 + (unsigned long)s->s2->tmp.cert_length +
        (unsigned long)s->s2->tmp.csl +
        (unsigned long)s->s2->tmp.conn_id_length;
    if (len > SSL2_MAX_RECORD_LENGTH_3_BYTE_HEADER) {
        SSLerr(SSL_F_GET_SERVER_HELLO, SSL_R_MESSAGE_TOO_LONG);
        return -1;
    }
    j = (int)len - s->init_num;
    i = ssl2_read(s, (char *)&(buf[s->init_num]), j);
    if (i != j)
        return (ssl2_part_read(s, SSL_F_GET_SERVER_HELLO, i));
    if (s->msg_callback) {
        /* SERVER-HELLO */
        s->msg_callback(0, s->version, 0, buf, (size_t)len, s,
                        s->msg_callback_arg);
    }

    /* things are looking good */

    p = buf + 11;
    if (s->hit) {
        if (s->s2->tmp.cert_length != 0) {
            SSLerr(SSL_F_GET_SERVER_HELLO, SSL_R_REUSE_CERT_LENGTH_NOT_ZERO);
            return (-1);
        }
        if (s->s2->tmp.cert_type != 0) {
            if (!(s->options & SSL_OP_SSLREF2_REUSE_CERT_TYPE_BUG)) {
                SSLerr(SSL_F_GET_SERVER_HELLO,
                       SSL_R_REUSE_CERT_TYPE_NOT_ZERO);
                return (-1);
            }
        }
        if (s->s2->tmp.csl != 0) {
            SSLerr(SSL_F_GET_SERVER_HELLO, SSL_R_REUSE_CIPHER_LIST_NOT_ZERO);
            return (-1);
        }
    } else {
# if 0
        /* very bad */
        memset(s->session->session_id, 0,
               SSL_MAX_SSL_SESSION_ID_LENGTH_IN_BYTES);
        s->session->session_id_length = 0;
# endif

        /*
         * we need to do this in case we were trying to reuse a client
         * session but others are already reusing it. If this was a new
         * 'blank' session ID, the session-id length will still be 0
         */
        if (s->session->session_id_length > 0) {
            if (!ssl_get_new_session(s, 0)) {
                ssl2_return_error(s, SSL2_PE_UNDEFINED_ERROR);
                return (-1);
            }
        }

        if (ssl2_set_certificate(s, s->s2->tmp.cert_type,
                                 s->s2->tmp.cert_length, p) <= 0) {
            ssl2_return_error(s, SSL2_PE_BAD_CERTIFICATE);
            return (-1);
        }
        p += s->s2->tmp.cert_length;

        if (s->s2->tmp.csl == 0) {
            ssl2_return_error(s, SSL2_PE_NO_CIPHER);
            SSLerr(SSL_F_GET_SERVER_HELLO, SSL_R_NO_CIPHER_LIST);
            return (-1);
        }

        /*
         * We have just received a list of ciphers back from the server.  We
         * need to get the ones that match, then select the one we want the
         * most :-).
         */

        /* load the ciphers */
        sk = ssl_bytes_to_cipher_list(s, p, s->s2->tmp.csl,
                                      &s->session->ciphers);
        p += s->s2->tmp.csl;
        if (sk == NULL) {
            ssl2_return_error(s, SSL2_PE_UNDEFINED_ERROR);
            SSLerr(SSL_F_GET_SERVER_HELLO, ERR_R_MALLOC_FAILURE);
            return (-1);
        }

        (void)sk_SSL_CIPHER_set_cmp_func(sk, ssl_cipher_ptr_id_cmp);

        /* get the array of ciphers we will accept */
        cl = SSL_get_ciphers(s);
        (void)sk_SSL_CIPHER_set_cmp_func(cl, ssl_cipher_ptr_id_cmp);

        /*
         * If server preference flag set, choose the first
         * (highest priority) cipher the server sends, otherwise
         * client preference has priority.
         */
        if (s->options & SSL_OP_CIPHER_SERVER_PREFERENCE) {
            prio = sk;
            allow = cl;
        } else {
            prio = cl;
            allow = sk;
        }
        /*
         * In theory we could have ciphers sent back that we don't want to
         * use but that does not matter since we will check against the list
         * we originally sent and for performance reasons we should not
         * bother to match the two lists up just to check.
         */
        for (i = 0; i < sk_SSL_CIPHER_num(prio); i++) {
            if (sk_SSL_CIPHER_find(allow, sk_SSL_CIPHER_value(prio, i)) >= 0)
                break;
        }

        if (i >= sk_SSL_CIPHER_num(prio)) {
            ssl2_return_error(s, SSL2_PE_NO_CIPHER);
            SSLerr(SSL_F_GET_SERVER_HELLO, SSL_R_NO_CIPHER_MATCH);
            return (-1);
        }
        s->session->cipher = sk_SSL_CIPHER_value(prio, i);

        if (s->session->peer != NULL) { /* can't happen */
            ssl2_return_error(s, SSL2_PE_UNDEFINED_ERROR);
            SSLerr(SSL_F_GET_SERVER_HELLO, ERR_R_INTERNAL_ERROR);
            return (-1);
        }

        s->session->peer = s->session->sess_cert->peer_key->x509;
        /* peer_key->x509 has been set by ssl2_set_certificate. */
        CRYPTO_add(&s->session->peer->references, 1, CRYPTO_LOCK_X509);
    }

    if (s->session->sess_cert == NULL
        || s->session->peer != s->session->sess_cert->peer_key->x509)
        /* can't happen */
    {
        ssl2_return_error(s, SSL2_PE_UNDEFINED_ERROR);
        SSLerr(SSL_F_GET_SERVER_HELLO, ERR_R_INTERNAL_ERROR);
        return (-1);
    }

    s->s2->conn_id_length = s->s2->tmp.conn_id_length;
    if (s->s2->conn_id_length > sizeof s->s2->conn_id) {
        ssl2_return_error(s, SSL2_PE_UNDEFINED_ERROR);
        SSLerr(SSL_F_GET_SERVER_HELLO, SSL_R_SSL2_CONNECTION_ID_TOO_LONG);
        return -1;
    }
    memcpy(s->s2->conn_id, p, s->s2->tmp.conn_id_length);
    return (1);
}

static int client_hello(SSL *s)
{
    unsigned char *buf;
    unsigned char *p, *d;
/*      CIPHER **cipher;*/
    int i, n, j;

    buf = (unsigned char *)s->init_buf->data;
    if (s->state == SSL2_ST_SEND_CLIENT_HELLO_A) {
        if ((s->session == NULL) || (s->session->ssl_version != s->version)) {
            if (!ssl_get_new_session(s, 0)) {
                ssl2_return_error(s, SSL2_PE_UNDEFINED_ERROR);
                return (-1);
            }
        }
        /* else use the pre-loaded session */

        p = buf;                /* header */
        d = p + 9;              /* data section */
        *(p++) = SSL2_MT_CLIENT_HELLO; /* type */
        s2n(SSL2_VERSION, p);   /* version */
        n = j = 0;

        n = ssl_cipher_list_to_bytes(s, SSL_get_ciphers(s), d, 0);
        d += n;

        if (n == 0) {
            SSLerr(SSL_F_CLIENT_HELLO, SSL_R_NO_CIPHERS_AVAILABLE);
            return (-1);
        }

        s2n(n, p);              /* cipher spec num bytes */

        if ((s->session->session_id_length > 0) &&
            (s->session->session_id_length <=
             SSL2_MAX_SSL_SESSION_ID_LENGTH)) {
            i = s->session->session_id_length;
            s2n(i, p);          /* session id length */
            memcpy(d, s->session->session_id, (unsigned int)i);
            d += i;
        } else {
            s2n(0, p);
        }

        s->s2->challenge_length = SSL2_CHALLENGE_LENGTH;
        s2n(SSL2_CHALLENGE_LENGTH, p); /* challenge length */
        /*
         * challenge id data
         */
        if (RAND_pseudo_bytes(s->s2->challenge, SSL2_CHALLENGE_LENGTH) <= 0)
            return -1;
        memcpy(d, s->s2->challenge, SSL2_CHALLENGE_LENGTH);
        d += SSL2_CHALLENGE_LENGTH;

        s->state = SSL2_ST_SEND_CLIENT_HELLO_B;
        s->init_num = d - buf;
        s->init_off = 0;
    }
    /* SSL2_ST_SEND_CLIENT_HELLO_B */
    return (ssl2_do_write(s));
}

static int client_master_key(SSL *s)
{
    unsigned char *buf;
    unsigned char *p, *d;
    int clear, enc, karg, i;
    SSL_SESSION *sess;
    const EVP_CIPHER *c;
    const EVP_MD *md;

    buf = (unsigned char *)s->init_buf->data;
    if (s->state == SSL2_ST_SEND_CLIENT_MASTER_KEY_A) {

        if (!ssl_cipher_get_evp(s->session, &c, &md, NULL, NULL, NULL)) {
            ssl2_return_error(s, SSL2_PE_NO_CIPHER);
            SSLerr(SSL_F_CLIENT_MASTER_KEY,
                   SSL_R_PROBLEMS_MAPPING_CIPHER_FUNCTIONS);
            return (-1);
        }
        sess = s->session;
        p = buf;
        d = p + 10;
        *(p++) = SSL2_MT_CLIENT_MASTER_KEY; /* type */

        i = ssl_put_cipher_by_char(s, sess->cipher, p);
        p += i;

        /* make key_arg data */
        i = EVP_CIPHER_iv_length(c);
        sess->key_arg_length = i;
        if (i > SSL_MAX_KEY_ARG_LENGTH) {
            ssl2_return_error(s, SSL2_PE_UNDEFINED_ERROR);
            SSLerr(SSL_F_CLIENT_MASTER_KEY, ERR_R_INTERNAL_ERROR);
            return -1;
        }
        if (i > 0)
            if (RAND_pseudo_bytes(sess->key_arg, i) <= 0)
                return -1;

        /* make a master key */
        i = EVP_CIPHER_key_length(c);
        sess->master_key_length = i;
        if (i > 0) {
            if (i > (int)sizeof(sess->master_key)) {
                ssl2_return_error(s, SSL2_PE_UNDEFINED_ERROR);
                SSLerr(SSL_F_CLIENT_MASTER_KEY, ERR_R_INTERNAL_ERROR);
                return -1;
            }
            if (RAND_bytes(sess->master_key, i) <= 0) {
                ssl2_return_error(s, SSL2_PE_UNDEFINED_ERROR);
                return (-1);
            }
        }

        if (sess->cipher->algorithm2 & SSL2_CF_8_BYTE_ENC)
            enc = 8;
        else if (SSL_C_IS_EXPORT(sess->cipher))
            enc = 5;
        else
            enc = i;

        if ((int)i < enc) {
            ssl2_return_error(s, SSL2_PE_UNDEFINED_ERROR);
            SSLerr(SSL_F_CLIENT_MASTER_KEY, SSL_R_CIPHER_TABLE_SRC_ERROR);
            return (-1);
        }
        clear = i - enc;
        s2n(clear, p);
        memcpy(d, sess->master_key, (unsigned int)clear);
        d += clear;

        enc = ssl_rsa_public_encrypt(sess->sess_cert, enc,
                                     &(sess->master_key[clear]), d,
                                     (s->
                                      s2->ssl2_rollback) ? RSA_SSLV23_PADDING
                                     : RSA_PKCS1_PADDING);
        if (enc <= 0) {
            ssl2_return_error(s, SSL2_PE_UNDEFINED_ERROR);
            SSLerr(SSL_F_CLIENT_MASTER_KEY, SSL_R_PUBLIC_KEY_ENCRYPT_ERROR);
            return (-1);
        }
# ifdef PKCS1_CHECK
        if (s->options & SSL_OP_PKCS1_CHECK_1)
            d[1]++;
        if (s->options & SSL_OP_PKCS1_CHECK_2)
            sess->master_key[clear]++;
# endif
        s2n(enc, p);
        d += enc;
        karg = sess->key_arg_length;
        s2n(karg, p);           /* key arg size */
        if (karg > (int)sizeof(sess->key_arg)) {
            ssl2_return_error(s, SSL2_PE_UNDEFINED_ERROR);
            SSLerr(SSL_F_CLIENT_MASTER_KEY, ERR_R_INTERNAL_ERROR);
            return -1;
        }
        memcpy(d, sess->key_arg, (unsigned int)karg);
        d += karg;

        s->state = SSL2_ST_SEND_CLIENT_MASTER_KEY_B;
        s->init_num = d - buf;
        s->init_off = 0;
    }

    /* SSL2_ST_SEND_CLIENT_MASTER_KEY_B */
    return (ssl2_do_write(s));
}

static int client_finished(SSL *s)
{
    unsigned char *p;

    if (s->state == SSL2_ST_SEND_CLIENT_FINISHED_A) {
        p = (unsigned char *)s->init_buf->data;
        *(p++) = SSL2_MT_CLIENT_FINISHED;
        if (s->s2->conn_id_length > sizeof s->s2->conn_id) {
            SSLerr(SSL_F_CLIENT_FINISHED, ERR_R_INTERNAL_ERROR);
            return -1;
        }
        memcpy(p, s->s2->conn_id, (unsigned int)s->s2->conn_id_length);

        s->state = SSL2_ST_SEND_CLIENT_FINISHED_B;
        s->init_num = s->s2->conn_id_length + 1;
        s->init_off = 0;
    }
    return (ssl2_do_write(s));
}

/* read the data and then respond */
static int client_certificate(SSL *s)
{
    unsigned char *buf;
    unsigned char *p, *d;
    int i;
    unsigned int n;
    int cert_ch_len;
    unsigned char *cert_ch;

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

    /*
     * We have a cert associated with the SSL, so attach it to the session if
     * it does not have one
     */

    if (s->state == SSL2_ST_SEND_CLIENT_CERTIFICATE_A) {
        i = ssl2_read(s, (char *)&(buf[s->init_num]),
                      SSL2_MAX_CERT_CHALLENGE_LENGTH + 2 - s->init_num);
        if (i < (SSL2_MIN_CERT_CHALLENGE_LENGTH + 2 - s->init_num))
            return (ssl2_part_read(s, SSL_F_CLIENT_CERTIFICATE, i));
        s->init_num += i;
        if (s->msg_callback) {
            /* REQUEST-CERTIFICATE */
            s->msg_callback(0, s->version, 0, buf, (size_t)s->init_num, s,
                            s->msg_callback_arg);
        }

        /* type=buf[0]; */
        /* type eq x509 */
        if (buf[1] != SSL2_AT_MD5_WITH_RSA_ENCRYPTION) {
            ssl2_return_error(s, SSL2_PE_UNSUPPORTED_CERTIFICATE_TYPE);
            SSLerr(SSL_F_CLIENT_CERTIFICATE, SSL_R_BAD_AUTHENTICATION_TYPE);
            return (-1);
        }

        if ((s->cert == NULL) ||
            (s->cert->key->x509 == NULL) ||
            (s->cert->key->privatekey == NULL)) {
            s->state = SSL2_ST_X509_GET_CLIENT_CERTIFICATE;
        } else
            s->state = SSL2_ST_SEND_CLIENT_CERTIFICATE_C;
    }

    cert_ch = buf + 2;
    cert_ch_len = s->init_num - 2;

    if (s->state == SSL2_ST_X509_GET_CLIENT_CERTIFICATE) {
        X509 *x509 = NULL;
        EVP_PKEY *pkey = NULL;

        /*
         * If we get an error we need to ssl->rwstate=SSL_X509_LOOKUP;
         * return(error); We should then be retried when things are ok and we
         * can get a cert or not
         */

        i = 0;
        if (s->ctx->client_cert_cb != NULL) {
            i = s->ctx->client_cert_cb(s, &(x509), &(pkey));
        }

        if (i < 0) {
            s->rwstate = SSL_X509_LOOKUP;
            return (-1);
        }
        s->rwstate = SSL_NOTHING;

        if ((i == 1) && (pkey != NULL) && (x509 != NULL)) {
            s->state = SSL2_ST_SEND_CLIENT_CERTIFICATE_C;
            if (!SSL_use_certificate(s, x509) || !SSL_use_PrivateKey(s, pkey)) {
                i = 0;
            }
            X509_free(x509);
            EVP_PKEY_free(pkey);
        } else if (i == 1) {
            if (x509 != NULL)
                X509_free(x509);
            if (pkey != NULL)
                EVP_PKEY_free(pkey);
            SSLerr(SSL_F_CLIENT_CERTIFICATE,
                   SSL_R_BAD_DATA_RETURNED_BY_CALLBACK);
            i = 0;
        }

        if (i == 0) {
            /*
             * We have no client certificate to respond with so send the
             * correct error message back
             */
            s->state = SSL2_ST_SEND_CLIENT_CERTIFICATE_B;
            p = buf;
            *(p++) = SSL2_MT_ERROR;
            s2n(SSL2_PE_NO_CERTIFICATE, p);
            s->init_off = 0;
            s->init_num = 3;
            /* Write is done at the end */
        }
    }

    if (s->state == SSL2_ST_SEND_CLIENT_CERTIFICATE_B) {
        return (ssl2_do_write(s));
    }

    if (s->state == SSL2_ST_SEND_CLIENT_CERTIFICATE_C) {
        EVP_MD_CTX ctx;

        /*
         * ok, now we calculate the checksum do it first so we can reuse buf
         * :-)
         */
        p = buf;
        EVP_MD_CTX_init(&ctx);
        EVP_SignInit_ex(&ctx, s->ctx->rsa_md5, NULL);
        EVP_SignUpdate(&ctx, s->s2->key_material, s->s2->key_material_length);
        EVP_SignUpdate(&ctx, cert_ch, (unsigned int)cert_ch_len);
        i = i2d_X509(s->session->sess_cert->peer_key->x509, &p);
        /*
         * Don't update the signature if it fails - FIXME: probably should
         * handle this better
         */
        if (i > 0)
            EVP_SignUpdate(&ctx, buf, (unsigned int)i);

        p = buf;
        d = p + 6;
        *(p++) = SSL2_MT_CLIENT_CERTIFICATE;
        *(p++) = SSL2_CT_X509_CERTIFICATE;
        n = i2d_X509(s->cert->key->x509, &d);
        s2n(n, p);

        if (!EVP_SignFinal(&ctx, d, &n, s->cert->key->privatekey)) {
            /*
             * this is not good.  If things have failed it means there so
             * something wrong with the key. We will continue with a 0 length
             * signature
             */
        }
        EVP_MD_CTX_cleanup(&ctx);
        s2n(n, p);
        d += n;

        s->state = SSL2_ST_SEND_CLIENT_CERTIFICATE_D;
        s->init_num = d - buf;
        s->init_off = 0;
    }
    /* if (s->state == SSL2_ST_SEND_CLIENT_CERTIFICATE_D) */
    return (ssl2_do_write(s));
}

static int get_server_verify(SSL *s)
{
    unsigned char *p;
    int i, n, len;

    p = (unsigned char *)s->init_buf->data;
    if (s->state == SSL2_ST_GET_SERVER_VERIFY_A) {
        i = ssl2_read(s, (char *)&(p[s->init_num]), 1 - s->init_num);
        if (i < (1 - s->init_num))
            return (ssl2_part_read(s, SSL_F_GET_SERVER_VERIFY, i));
        s->init_num += i;

        s->state = SSL2_ST_GET_SERVER_VERIFY_B;
        if (*p != SSL2_MT_SERVER_VERIFY) {
            if (p[0] != SSL2_MT_ERROR) {
                ssl2_return_error(s, SSL2_PE_UNDEFINED_ERROR);
                SSLerr(SSL_F_GET_SERVER_VERIFY, SSL_R_READ_WRONG_PACKET_TYPE);
            } else {
                SSLerr(SSL_F_GET_SERVER_VERIFY, SSL_R_PEER_ERROR);
                /* try to read the error message */
                i = ssl2_read(s, (char *)&(p[s->init_num]), 3 - s->init_num);
                return ssl2_part_read(s, SSL_F_GET_SERVER_VERIFY, i);
            }
            return (-1);
        }
    }

    p = (unsigned char *)s->init_buf->data;
    len = 1 + s->s2->challenge_length;
    n = len - s->init_num;
    i = ssl2_read(s, (char *)&(p[s->init_num]), n);
    if (i < n)
        return (ssl2_part_read(s, SSL_F_GET_SERVER_VERIFY, i));
    if (s->msg_callback) {
        /* SERVER-VERIFY */
        s->msg_callback(0, s->version, 0, p, len, s, s->msg_callback_arg);
    }
    p += 1;

    if (CRYPTO_memcmp(p, s->s2->challenge, s->s2->challenge_length) != 0) {
        ssl2_return_error(s, SSL2_PE_UNDEFINED_ERROR);
        SSLerr(SSL_F_GET_SERVER_VERIFY, SSL_R_CHALLENGE_IS_DIFFERENT);
        return (-1);
    }
    return (1);
}

static int get_server_finished(SSL *s)
{
    unsigned char *buf;
    unsigned char *p;
    int i, n, len;

    buf = (unsigned char *)s->init_buf->data;
    p = buf;
    if (s->state == SSL2_ST_GET_SERVER_FINISHED_A) {
        i = ssl2_read(s, (char *)&(buf[s->init_num]), 1 - s->init_num);
        if (i < (1 - s->init_num))
            return (ssl2_part_read(s, SSL_F_GET_SERVER_FINISHED, i));
        s->init_num += i;

        if (*p == SSL2_MT_REQUEST_CERTIFICATE) {
            s->state = SSL2_ST_SEND_CLIENT_CERTIFICATE_A;
            return (1);
        } else if (*p != SSL2_MT_SERVER_FINISHED) {
            if (p[0] != SSL2_MT_ERROR) {
                ssl2_return_error(s, SSL2_PE_UNDEFINED_ERROR);
                SSLerr(SSL_F_GET_SERVER_FINISHED,
                       SSL_R_READ_WRONG_PACKET_TYPE);
            } else {
                SSLerr(SSL_F_GET_SERVER_FINISHED, SSL_R_PEER_ERROR);
                /* try to read the error message */
                i = ssl2_read(s, (char *)&(p[s->init_num]), 3 - s->init_num);
                return ssl2_part_read(s, SSL_F_GET_SERVER_VERIFY, i);
            }
            return (-1);
        }
        s->state = SSL2_ST_GET_SERVER_FINISHED_B;
    }

    len = 1 + SSL2_SSL_SESSION_ID_LENGTH;
    n = len - s->init_num;
    i = ssl2_read(s, (char *)&(buf[s->init_num]), n);
    if (i < n) {
        /*
         * XXX could be shorter than SSL2_SSL_SESSION_ID_LENGTH,
         * that's the maximum
         */
        return (ssl2_part_read(s, SSL_F_GET_SERVER_FINISHED, i));
    }
    s->init_num += i;
    if (s->msg_callback) {
        /* SERVER-FINISHED */
        s->msg_callback(0, s->version, 0, buf, (size_t)s->init_num, s,
                        s->msg_callback_arg);
    }

    if (!s->hit) {              /* new session */
        /* new session-id */
        /*
         * Make sure we were not trying to re-use an old SSL_SESSION or bad
         * things can happen
         */
        /* ZZZZZZZZZZZZZ */
        s->session->session_id_length = SSL2_SSL_SESSION_ID_LENGTH;
        memcpy(s->session->session_id, p + 1, SSL2_SSL_SESSION_ID_LENGTH);
    } else {
        if (!(s->options & SSL_OP_MICROSOFT_SESS_ID_BUG)) {
            if ((s->session->session_id_length >
                 sizeof s->session->session_id)
                || (0 !=
                    memcmp(buf + 1, s->session->session_id,
                           (unsigned int)s->session->session_id_length))) {
                ssl2_return_error(s, SSL2_PE_UNDEFINED_ERROR);
                SSLerr(SSL_F_GET_SERVER_FINISHED,
                       SSL_R_SSL_SESSION_ID_IS_DIFFERENT);
                return (-1);
            }
        }
    }
    s->state = SSL_ST_OK;
    return (1);
}

/* loads in the certificate from the server */
int ssl2_set_certificate(SSL *s, int type, int len, const unsigned char *data)
{
    STACK_OF(X509) *sk = NULL;
    EVP_PKEY *pkey = NULL;
    SESS_CERT *sc = NULL;
    int i;
    X509 *x509 = NULL;
    int ret = 0;

    x509 = d2i_X509(NULL, &data, (long)len);
    if (x509 == NULL) {
        SSLerr(SSL_F_SSL2_SET_CERTIFICATE, ERR_R_X509_LIB);
        goto err;
    }

    if ((sk = sk_X509_new_null()) == NULL || !sk_X509_push(sk, x509)) {
        SSLerr(SSL_F_SSL2_SET_CERTIFICATE, ERR_R_MALLOC_FAILURE);
        goto err;
    }

    i = ssl_verify_cert_chain(s, sk);

    if ((s->verify_mode != SSL_VERIFY_NONE) && (i <= 0)) {
        SSLerr(SSL_F_SSL2_SET_CERTIFICATE, SSL_R_CERTIFICATE_VERIFY_FAILED);
        goto err;
    }
    ERR_clear_error();          /* but we keep s->verify_result */
    s->session->verify_result = s->verify_result;

    /* server's cert for this session */
    sc = ssl_sess_cert_new();
    if (sc == NULL) {
        ret = -1;
        goto err;
    }
    if (s->session->sess_cert)
        ssl_sess_cert_free(s->session->sess_cert);
    s->session->sess_cert = sc;

    sc->peer_pkeys[SSL_PKEY_RSA_ENC].x509 = x509;
    sc->peer_key = &(sc->peer_pkeys[SSL_PKEY_RSA_ENC]);

    pkey = X509_get_pubkey(x509);
    x509 = NULL;
    if (pkey == NULL) {
        SSLerr(SSL_F_SSL2_SET_CERTIFICATE,
               SSL_R_UNABLE_TO_EXTRACT_PUBLIC_KEY);
        goto err;
    }
    if (pkey->type != EVP_PKEY_RSA) {
        SSLerr(SSL_F_SSL2_SET_CERTIFICATE, SSL_R_PUBLIC_KEY_NOT_RSA);
        goto err;
    }

    if (!ssl_set_peer_cert_type(sc, SSL2_CT_X509_CERTIFICATE))
        goto err;
    ret = 1;
 err:
    sk_X509_free(sk);
    X509_free(x509);
    EVP_PKEY_free(pkey);
    return (ret);
}

static int ssl_rsa_public_encrypt(SESS_CERT *sc, int len, unsigned char *from,
                                  unsigned char *to, int padding)
{
    EVP_PKEY *pkey = NULL;
    int i = -1;

    if ((sc == NULL) || (sc->peer_key->x509 == NULL) ||
        ((pkey = X509_get_pubkey(sc->peer_key->x509)) == NULL)) {
        SSLerr(SSL_F_SSL_RSA_PUBLIC_ENCRYPT, SSL_R_NO_PUBLICKEY);
        return (-1);
    }
    if (pkey->type != EVP_PKEY_RSA) {
        SSLerr(SSL_F_SSL_RSA_PUBLIC_ENCRYPT, SSL_R_PUBLIC_KEY_IS_NOT_RSA);
        goto end;
    }

    /* we have the public key */
    i = RSA_public_encrypt(len, from, to, pkey->pkey.rsa, padding);
    if (i < 0)
        SSLerr(SSL_F_SSL_RSA_PUBLIC_ENCRYPT, ERR_R_RSA_LIB);
 end:
    EVP_PKEY_free(pkey);
    return (i);
}
#else                           /* !OPENSSL_NO_SSL2 */

# if PEDANTIC
static void *dummy = &dummy;
# endif

#endif