openssl/ssl/record/ssl3_buffer.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) 1998-2002 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
 *    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"
#include "record_locl.h"

void SSL3_BUFFER_set_data(SSL3_BUFFER *b, const unsigned char *d, int n)
{
    if (d != NULL)
        memcpy(b->buf, d, n);
    b->left = n;
    b->offset = 0;
}

/*
 * Clear the contents of an SSL3_BUFFER but retain any memory allocated
 */
void SSL3_BUFFER_clear(SSL3_BUFFER *b)
{
    unsigned char *buf = b->buf;
    size_t len = b->len;

    memset(b, 0, sizeof(*b));
    b->buf = buf;
    b->len = len;
}

void SSL3_BUFFER_release(SSL3_BUFFER *b)
{
    OPENSSL_free(b->buf);
    b->buf = NULL;
}

int ssl3_setup_read_buffer(SSL *s)
{
    unsigned char *p;
    size_t len, align = 0, headerlen;
    SSL3_BUFFER *b;
    
    b = RECORD_LAYER_get_rbuf(&s->rlayer);

    if (SSL_IS_DTLS(s))
        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 (b->buf == NULL) {
        len = SSL3_RT_MAX_PLAIN_LENGTH
            + SSL3_RT_MAX_ENCRYPTED_OVERHEAD + headerlen + align;
#ifndef OPENSSL_NO_COMP
        if (ssl_allow_compression(s))
            len += SSL3_RT_MAX_COMPRESSED_OVERHEAD;
#endif
        if ((p = OPENSSL_malloc(len)) == NULL)
            goto err;
        b->buf = p;
        b->len = len;
    }

    RECORD_LAYER_set_packet(&s->rlayer, &(b->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;
    SSL3_BUFFER *wb;

    wb = RECORD_LAYER_get_wbuf(&s->rlayer);

    if (SSL_IS_DTLS(s))
        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 (wb->buf == NULL) {
        len = s->max_send_fragment
            + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD + headerlen + align;
#ifndef OPENSSL_NO_COMP
        if (ssl_allow_compression(s))
            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 = OPENSSL_malloc(len)) == NULL)
            goto err;
        wb->buf = p;
        wb->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)
{
    SSL3_BUFFER *wb;

    wb = RECORD_LAYER_get_wbuf(&s->rlayer);

    OPENSSL_free(wb->buf);
    wb->buf = NULL;
    return 1;
}

int ssl3_release_read_buffer(SSL *s)
{
    SSL3_BUFFER *b;

    b = RECORD_LAYER_get_rbuf(&s->rlayer);
    OPENSSL_free(b->buf);
    b->buf = NULL;
    return 1;
}