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- /* 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) 1998-2006 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 <assert.h>
- #include <stdio.h>
-
- #include <openssl/buf.h>
- #include <openssl/err.h>
- #include <openssl/evp.h>
- #include <openssl/mem.h>
- #include <openssl/obj.h>
- #include <openssl/rand.h>
-
- #include "ssl_locl.h"
-
- static int ssl23_get_client_hello(SSL *s);
- static int ssl23_get_v2_client_hello(SSL *s);
-
- static const SSL_METHOD *ssl23_get_server_method(int ver)
- {
- if (ver == SSL3_VERSION)
- return(SSLv3_server_method());
- else if (ver == TLS1_VERSION)
- return(TLSv1_server_method());
- else if (ver == TLS1_1_VERSION)
- return(TLSv1_1_server_method());
- else if (ver == TLS1_2_VERSION)
- return(TLSv1_2_server_method());
- else
- return(NULL);
- }
-
- IMPLEMENT_ssl23_meth_func(SSLv23_server_method,
- ssl23_accept,
- ssl_undefined_function)
-
- int ssl23_accept(SSL *s)
- {
- BUF_MEM *buf;
- void (*cb)(const SSL *ssl,int type,int val)=NULL;
- int ret= -1;
- int new_state,state;
-
- ERR_clear_error();
- ERR_clear_system_error();
-
- if (s->info_callback != NULL)
- cb=s->info_callback;
- else if (s->ctx->info_callback != NULL)
- cb=s->ctx->info_callback;
-
- 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_ACCEPT:
- case SSL_ST_BEFORE|SSL_ST_ACCEPT:
- case SSL_ST_OK|SSL_ST_ACCEPT:
-
- s->server=1;
- if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_START,1);
-
- /* s->version=SSL3_VERSION; */
- s->type=SSL_ST_ACCEPT;
-
- if (s->init_buf == NULL)
- {
- if ((buf=BUF_MEM_new()) == NULL)
- {
- ret= -1;
- goto end;
- }
- if (!BUF_MEM_grow(buf,SSL3_RT_MAX_PLAIN_LENGTH))
- {
- ret= -1;
- goto end;
- }
- s->init_buf=buf;
- }
-
- if (!ssl3_init_finished_mac(s))
- {
- OPENSSL_PUT_ERROR(SSL, ssl23_accept, ERR_R_INTERNAL_ERROR);
- ret = -1;
- goto end;
- }
-
- s->state=SSL23_ST_SR_CLNT_HELLO;
- s->ctx->stats.sess_accept++;
- s->init_num=0;
- break;
-
- case SSL23_ST_SR_CLNT_HELLO:
- s->shutdown = 0;
- ret = ssl23_get_client_hello(s);
- if (ret <= 0) goto end;
- break;
-
- case SSL23_ST_SR_V2_CLNT_HELLO:
- ret = ssl23_get_v2_client_hello(s);
- if (ret <= 0) goto end;
- break;
-
- case SSL23_ST_SR_SWITCH_VERSION:
- if (!ssl_init_wbio_buffer(s, 1))
- {
- ret = -1;
- goto end;
- }
-
- s->state = SSL3_ST_SR_CLNT_HELLO_A;
- s->method = ssl23_get_server_method(s->version);
- assert(s->method != NULL);
- s->handshake_func = s->method->ssl_accept;
- s->init_num = 0;
-
- /* NULL the callback; SSL_accept will call it instead. */
- cb = NULL;
- ret = SSL_accept(s);
- goto end;
- /* break; */
-
- default:
- OPENSSL_PUT_ERROR(SSL, ssl23_accept, SSL_R_UNKNOWN_STATE);
- ret= -1;
- goto end;
- /* break; */
- }
-
- if ((cb != NULL) && (s->state != state))
- {
- new_state=s->state;
- s->state=state;
- cb(s,SSL_CB_ACCEPT_LOOP,1);
- s->state=new_state;
- }
- }
- end:
- s->in_handshake--;
- if (cb != NULL)
- cb(s,SSL_CB_ACCEPT_EXIT,ret);
- return(ret);
- }
-
- /* ssl23_get_mutual_version determines the highest supported version for a
- * client which reports a highest version of |client_version|. On success, it
- * returns 1 and sets |*out_version| to the negotiated version. Otherwise, it
- * returns 0. */
- static int ssl23_get_mutual_version(SSL *s, int *out_version, uint16_t client_version)
- {
- if (client_version >= TLS1_2_VERSION && !(s->options & SSL_OP_NO_TLSv1_2))
- {
- *out_version = TLS1_2_VERSION;
- return 1;
- }
- if (client_version >= TLS1_1_VERSION && !(s->options & SSL_OP_NO_TLSv1_1))
- {
- *out_version = TLS1_1_VERSION;
- return 1;
- }
- if (client_version >= TLS1_VERSION && !(s->options & SSL_OP_NO_TLSv1))
- {
- *out_version = TLS1_VERSION;
- return 1;
- }
- if (client_version >= SSL3_VERSION && !(s->options & SSL_OP_NO_SSLv3))
- {
- *out_version = SSL3_VERSION;
- return 1;
- }
- return 0;
- }
-
- static int ssl23_get_client_hello(SSL *s)
- {
- uint8_t *p;
- int n = 0;
-
- /* Sniff enough of the input to determine ClientHello type and the
- * client version. */
- if (!ssl3_setup_buffers(s)) goto err;
-
- /* Read the initial 11 bytes of the input. This is sufficient to
- * determine the client version for a ClientHello or a
- * V2ClientHello.
- *
- * ClientHello (assuming client_version is unfragmented):
- * Byte Content
- * 0 type \
- * 1-2 version > record header
- * 3-4 length /
- * 5 msg_type \
- * 6-8 length > Client Hello message
- * 9-10 client_version /
- *
- * V2ClientHello:
- * Byte Content
- * 0-1 msg_length
- * 2 msg_type
- * 3-4 version
- * 5-6 cipher_spec_length
- * 7-8 session_id_length
- * 9-10 challenge_length
- */
- n = ssl23_read_bytes(s, 11);
- if (n <= 0)
- return n;
- assert(n == 11);
-
- p = s->packet;
-
- /* Some dedicated error codes for protocol mixups should the application
- * wish to interpret them differently. (These do not overlap with
- * ClientHello or V2ClientHello.) */
- if ((strncmp("GET ", (char *)p, 4) == 0) ||
- (strncmp("POST ",(char *)p, 5) == 0) ||
- (strncmp("HEAD ",(char *)p, 5) == 0) ||
- (strncmp("PUT ", (char *)p, 4) == 0))
- {
- OPENSSL_PUT_ERROR(SSL, ssl23_get_client_hello, SSL_R_HTTP_REQUEST);
- goto err;
- }
- if (strncmp("CONNECT",(char *)p, 7) == 0)
- {
- OPENSSL_PUT_ERROR(SSL, ssl23_get_client_hello, SSL_R_HTTPS_PROXY_REQUEST);
- goto err;
- }
-
- /* Determine if this is a ClientHello or V2ClientHello. */
- if ((p[0] & 0x80) && (p[2] == SSL2_MT_CLIENT_HELLO))
- {
- /* This is a V2ClientHello. Determine the version to
- * use. */
- uint16_t client_version = (p[3] << 8) | p[4];
- if (!ssl23_get_mutual_version(s, &s->version, client_version))
- {
- OPENSSL_PUT_ERROR(SSL, ssl23_get_client_hello, SSL_R_UNSUPPORTED_PROTOCOL);
- goto err;
- }
- /* Parse the entire V2ClientHello. */
- s->state = SSL23_ST_SR_V2_CLNT_HELLO;
- }
- else if ((p[0] == SSL3_RT_HANDSHAKE) &&
- (p[1] >= SSL3_VERSION_MAJOR) &&
- (p[5] == SSL3_MT_CLIENT_HELLO))
- {
- /* This is a fragment of a ClientHello. We look at the
- * client_hello to negotiate the version. However, this
- * is difficult if we have only a pathologically small
- * fragment. No known client fragments ClientHello like
- * this, so we simply reject such connections to avoid
- * protocol version downgrade attacks. */
- uint16_t record_length = (p[3] << 8) | p[4];
- uint16_t client_version;
- if (record_length < 6)
- {
- OPENSSL_PUT_ERROR(SSL, ssl23_get_client_hello, SSL_R_RECORD_TOO_SMALL);
- goto err;
- }
-
- client_version = (p[9] << 8) | p[10];
- if (!ssl23_get_mutual_version(s, &s->version, client_version))
- {
- OPENSSL_PUT_ERROR(SSL, ssl23_get_client_hello, SSL_R_UNSUPPORTED_PROTOCOL);
- goto err;
- }
-
- /* Reset the record-layer state for SSL3. */
- assert(s->rstate == SSL_ST_READ_HEADER);
- s->s3->rbuf.left = s->packet_length;
- s->s3->rbuf.offset = 0;
- s->packet_length = 0;
-
- /* Ready to switch versions. */
- s->state = SSL23_ST_SR_SWITCH_VERSION;
- }
-
- return 1;
- err:
- return -1;
- }
-
- static int ssl23_get_v2_client_hello(SSL *s)
- {
- uint8_t *p;
- size_t i;
- int n = 0;
-
- CBS v2_client_hello, cipher_specs, session_id, challenge;
- size_t msg_length, len;
- uint8_t msg_type;
- uint16_t version, cipher_spec_length, session_id_length, challenge_length;
- CBB client_hello, hello_body, cipher_suites;
- uint8_t random[SSL3_RANDOM_SIZE];
-
- /* Read the remainder of the V2ClientHello. We have previously read 11
- * bytes in ssl23_get_client_hello. */
- p = s->packet;
- msg_length = ((p[0] & 0x7f) << 8) | p[1];
- if (msg_length > (1024 * 4))
- {
- OPENSSL_PUT_ERROR(SSL, ssl23_get_v2_client_hello, SSL_R_RECORD_TOO_LARGE);
- goto err;
- }
- if (msg_length < 11 - 2)
- {
- /* Reject lengths that are too short early. We have already read
- * 11 bytes, so we should not attempt to process an (invalid)
- * V2ClientHello which would be shorter than that. */
- OPENSSL_PUT_ERROR(SSL, ssl23_get_v2_client_hello, SSL_R_RECORD_LENGTH_MISMATCH);
- goto err;
- }
- n = ssl23_read_bytes(s, msg_length + 2);
- if (n <= 0)
- return n;
- assert(n == s->packet_length);
-
- /* The V2ClientHello without the length is incorporated into the
- * Finished hash. */
- ssl3_finish_mac(s, s->packet + 2, s->packet_length - 2);
- if (s->msg_callback)
- s->msg_callback(0, SSL2_VERSION, 0, s->packet+2, s->packet_length-2, s, s->msg_callback_arg); /* CLIENT-HELLO */
-
- CBS_init(&v2_client_hello, s->packet + 2, s->packet_length - 2);
- if (!CBS_get_u8(&v2_client_hello, &msg_type) ||
- !CBS_get_u16(&v2_client_hello, &version) ||
- !CBS_get_u16(&v2_client_hello, &cipher_spec_length) ||
- !CBS_get_u16(&v2_client_hello, &session_id_length) ||
- !CBS_get_u16(&v2_client_hello, &challenge_length) ||
- !CBS_get_bytes(&v2_client_hello, &cipher_specs, cipher_spec_length) ||
- !CBS_get_bytes(&v2_client_hello, &session_id, session_id_length) ||
- !CBS_get_bytes(&v2_client_hello, &challenge, challenge_length) ||
- CBS_len(&v2_client_hello) != 0)
- {
- OPENSSL_PUT_ERROR(SSL, ssl23_get_v2_client_hello, SSL_R_DECODE_ERROR);
- goto err;
- }
-
- /* msg_type has already been checked. */
- assert(msg_type == SSL2_MT_CLIENT_HELLO);
-
- /* The client_random is the V2ClientHello challenge. Truncate or
- * left-pad with zeros as needed. */
- memset(random, 0, SSL3_RANDOM_SIZE);
- i = (CBS_len(&challenge) > SSL3_RANDOM_SIZE) ? SSL3_RANDOM_SIZE : CBS_len(&challenge);
- memcpy(random, CBS_data(&challenge), i);
-
- /* Write out an equivalent SSLv3 ClientHello. */
- if (!CBB_init_fixed(&client_hello, (uint8_t *)s->init_buf->data, s->init_buf->max))
- {
- OPENSSL_PUT_ERROR(SSL, ssl23_get_v2_client_hello, ERR_R_MALLOC_FAILURE);
- goto err;
- }
- if (!CBB_add_u8(&client_hello, SSL3_MT_CLIENT_HELLO) ||
- !CBB_add_u24_length_prefixed(&client_hello, &hello_body) ||
- !CBB_add_u16(&hello_body, version) ||
- !CBB_add_bytes(&hello_body, random, SSL3_RANDOM_SIZE) ||
- /* No session id. */
- !CBB_add_u8(&hello_body, 0) ||
- !CBB_add_u16_length_prefixed(&hello_body, &cipher_suites))
- {
- CBB_cleanup(&client_hello);
- OPENSSL_PUT_ERROR(SSL, ssl23_get_v2_client_hello, ERR_R_INTERNAL_ERROR);
- goto err;
- }
-
- /* Copy the cipher suites. */
- while (CBS_len(&cipher_specs) > 0)
- {
- uint32_t cipher_spec;
- if (!CBS_get_u24(&cipher_specs, &cipher_spec))
- {
- CBB_cleanup(&client_hello);
- OPENSSL_PUT_ERROR(SSL, ssl23_get_v2_client_hello, SSL_R_DECODE_ERROR);
- goto err;
- }
-
- /* Skip SSLv2 ciphers. */
- if ((cipher_spec & 0xff0000) != 0)
- continue;
- if (!CBB_add_u16(&cipher_suites, cipher_spec))
- {
- CBB_cleanup(&client_hello);
- OPENSSL_PUT_ERROR(SSL, ssl23_get_v2_client_hello, ERR_R_INTERNAL_ERROR);
- goto err;
- }
- }
-
- /* Add the null compression scheme and finish. */
- if (!CBB_add_u8(&hello_body, 1) ||
- !CBB_add_u8(&hello_body, 0) ||
- !CBB_finish(&client_hello, NULL, &len))
- {
- CBB_cleanup(&client_hello);
- OPENSSL_PUT_ERROR(SSL, ssl23_get_v2_client_hello, ERR_R_INTERNAL_ERROR);
- goto err;
- }
-
- /* Mark the message for "re"-use by the version-specific
- * method. */
- s->s3->tmp.reuse_message = 1;
- s->s3->tmp.message_type = SSL3_MT_CLIENT_HELLO;
- /* The handshake message header is 4 bytes. */
- s->s3->tmp.message_size = len - 4;
-
- /* Reset the record layer for SSL3. */
- assert(s->rstate == SSL_ST_READ_HEADER);
- s->packet_length = 0;
- s->s3->rbuf.left = 0;
- s->s3->rbuf.offset = 0;
-
- s->state = SSL23_ST_SR_SWITCH_VERSION;
- return 1;
- err:
- return -1;
- }
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