/* $OpenBSD: ssl_both.c,v 1.42 2022/02/05 14:54:10 jsing Exp $ */

/* 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).

 *

 */

/* ====================================================================

 * 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 <stdio.h>

#include <string.h>

#include <openssl/buffer.h>

#include <openssl/evp.h>

#include <openssl/objects.h>

#include <openssl/x509.h>

#include "bytestring.h"

#include "dtls_locl.h"

#include "ssl_locl.h"

/*

 * Send s->internal->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->internal->init_buf->data[s->internal->init_off],

      s->internal->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.

     */

    tls1_transcript_record(s,

        (unsigned char *)&s->internal->init_buf->data[s->internal->init_off], ret);

  if (ret == s->internal->init_num) {

    ssl_msg_callback(s, 1, type, s->internal->init_buf->data,

        (size_t)(s->internal->init_off + s->internal->init_num));

    return (1);

  }

  s->internal->init_off += ret;

  s->internal->init_num -= ret;

  return (0);

}

int

ssl3_send_finished(SSL *s, int state_a, int state_b)

{

  CBB cbb, finished;

  memset(&cbb, 0, sizeof(cbb));

  if (s->s3->hs.state == state_a) {

    if (!tls12_derive_finished(s))

      goto err;

    /* Copy finished so we can use it for renegotiation checks. */

    if (!s->server) {

      memcpy(s->s3->previous_client_finished,

          s->s3->hs.finished, s->s3->hs.finished_len);

      s->s3->previous_client_finished_len =

          s->s3->hs.finished_len;

    } else {

      memcpy(s->s3->previous_server_finished,

          s->s3->hs.finished, s->s3->hs.finished_len);

      s->s3->previous_server_finished_len =

          s->s3->hs.finished_len;

    }

    if (!ssl3_handshake_msg_start(s, &cbb, &finished,

        SSL3_MT_FINISHED))

                        goto err;

    if (!CBB_add_bytes(&finished, s->s3->hs.finished,

        s->s3->hs.finished_len))

      goto err;

    if (!ssl3_handshake_msg_finish(s, &cbb))

      goto err;

    s->s3->hs.state = state_b;

  }

  return (ssl3_handshake_write(s));

 err:

  CBB_cleanup(&cbb);

  return (-1);

}

int

ssl3_get_finished(SSL *s, int a, int b)

{

  int al, md_len, ret;

  CBS cbs;

  /* should actually be 36+4 :-) */

  if ((ret = ssl3_get_message(s, a, b, SSL3_MT_FINISHED, 64)) <= 0)

    return ret;

  /* If this occurs, we have missed a message */

  if (!s->s3->change_cipher_spec) {

    al = SSL_AD_UNEXPECTED_MESSAGE;

    SSLerror(s, SSL_R_GOT_A_FIN_BEFORE_A_CCS);

    goto fatal_err;

  }

  s->s3->change_cipher_spec = 0;

  md_len = TLS1_FINISH_MAC_LENGTH;

  if (s->internal->init_num < 0) {

    al = SSL_AD_DECODE_ERROR;

    SSLerror(s, SSL_R_BAD_DIGEST_LENGTH);

    goto fatal_err;

  }

  CBS_init(&cbs, s->internal->init_msg, s->internal->init_num);

  if (s->s3->hs.peer_finished_len != md_len ||

      CBS_len(&cbs) != md_len) {

    al = SSL_AD_DECODE_ERROR;

    SSLerror(s, SSL_R_BAD_DIGEST_LENGTH);

    goto fatal_err;

  }

  if (!CBS_mem_equal(&cbs, s->s3->hs.peer_finished, CBS_len(&cbs))) {

    al = SSL_AD_DECRYPT_ERROR;

    SSLerror(s, SSL_R_DIGEST_CHECK_FAILED);

    goto fatal_err;

  }

  /* Copy finished so we can use it for renegotiation checks. */

  OPENSSL_assert(md_len <= EVP_MAX_MD_SIZE);

  if (s->server) {

    memcpy(s->s3->previous_client_finished,

        s->s3->hs.peer_finished, md_len);

    s->s3->previous_client_finished_len = md_len;

  } else {

    memcpy(s->s3->previous_server_finished,

        s->s3->hs.peer_finished, md_len);

    s->s3->previous_server_finished_len = md_len;

  }

  return (1);

 fatal_err:

  ssl3_send_alert(s, SSL3_AL_FATAL, al);

  return (0);

}

int

ssl3_send_change_cipher_spec(SSL *s, int a, int b)

{

  size_t outlen;

  CBB cbb;

  memset(&cbb, 0, sizeof(cbb));

  if (s->s3->hs.state == a) {

    if (!CBB_init_fixed(&cbb, s->internal->init_buf->data,

        s->internal->init_buf->length))

      goto err;

    if (!CBB_add_u8(&cbb, SSL3_MT_CCS))

      goto err;

    if (!CBB_finish(&cbb, NULL, &outlen))

      goto err;

    if (outlen > INT_MAX)

      goto err;

    s->internal->init_num = (int)outlen;

    s->internal->init_off = 0;

    if (SSL_is_dtls(s)) {

      s->d1->handshake_write_seq =

          s->d1->next_handshake_write_seq;

      dtls1_set_message_header_int(s, SSL3_MT_CCS, 0,

          s->d1->handshake_write_seq, 0, 0);

      dtls1_buffer_message(s, 1);

    }

    s->s3->hs.state = b;

  }

  /* SSL3_ST_CW_CHANGE_B */

  return ssl3_record_write(s, SSL3_RT_CHANGE_CIPHER_SPEC);

 err:

  CBB_cleanup(&cbb);

  return -1;

}

static int

ssl3_add_cert(CBB *cbb, X509 *x)

{

  unsigned char *data;

  int cert_len;

  int ret = 0;

  CBB cert;

  if ((cert_len = i2d_X509(x, NULL)) < 0)

    goto err;

  if (!CBB_add_u24_length_prefixed(cbb, &cert))

    goto err;

  if (!CBB_add_space(&cert, &data, cert_len))

    goto err;

  if (i2d_X509(x, &data) < 0)

    goto err;

  if (!CBB_flush(cbb))

    goto err;

  ret = 1;

 err:

  return (ret);

}

int

ssl3_output_cert_chain(SSL *s, CBB *cbb, SSL_CERT_PKEY *cpk)

{

  X509_STORE_CTX *xs_ctx = NULL;

  STACK_OF(X509) *chain;

  CBB cert_list;

  X509 *x;

  int ret = 0;

  int i;

  if (!CBB_add_u24_length_prefixed(cbb, &cert_list))

    goto err;

  /* Send an empty certificate list when no certificate is available. */

  if (cpk == NULL)

    goto done;

  if ((chain = cpk->chain) == NULL)

    chain = s->ctx->extra_certs;

  if (chain != NULL || (s->internal->mode & SSL_MODE_NO_AUTO_CHAIN)) {

    if (!ssl3_add_cert(&cert_list, cpk->x509))

      goto err;

  } else {

    if ((xs_ctx = X509_STORE_CTX_new()) == NULL)

      goto err;

    if (!X509_STORE_CTX_init(xs_ctx, s->ctx->cert_store,

        cpk->x509, NULL)) {

      SSLerror(s, ERR_R_X509_LIB);

      goto err;

    }

    X509_VERIFY_PARAM_set_flags(X509_STORE_CTX_get0_param(xs_ctx),

        X509_V_FLAG_LEGACY_VERIFY);

    X509_verify_cert(xs_ctx);

    ERR_clear_error();

    chain = X509_STORE_CTX_get0_chain(xs_ctx);

  }

  for (i = 0; i < sk_X509_num(chain); i++) {

    x = sk_X509_value(chain, i);

    if (!ssl3_add_cert(&cert_list, x))

      goto err;

  }

 done:

  if (!CBB_flush(cbb))

    goto err;

  ret = 1;

 err:

  X509_STORE_CTX_free(xs_ctx);

  return (ret);

}

/*

 * 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'.

 */

int

ssl3_get_message(SSL *s, int st1, int stn, int mt, long max)

{

  unsigned char *p;

  uint32_t l;

  long n;

  int i, al;

  CBS cbs;

  uint8_t u8;

  if (SSL_is_dtls(s))

    return dtls1_get_message(s, st1, stn, mt, max);

  if (s->s3->hs.tls12.reuse_message) {

    s->s3->hs.tls12.reuse_message = 0;

    if ((mt >= 0) && (s->s3->hs.tls12.message_type != mt)) {

      al = SSL_AD_UNEXPECTED_MESSAGE;

      SSLerror(s, SSL_R_UNEXPECTED_MESSAGE);

      goto fatal_err;

    }

    s->internal->init_msg = s->internal->init_buf->data +

        SSL3_HM_HEADER_LENGTH;

    s->internal->init_num = (int)s->s3->hs.tls12.message_size;

    return 1;

  }

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

  if (s->s3->hs.state == st1) {

    int skip_message;

    do {

      while (s->internal->init_num < SSL3_HM_HEADER_LENGTH) {

        i = s->method->ssl_read_bytes(s,

            SSL3_RT_HANDSHAKE, &p[s->internal->init_num],

            SSL3_HM_HEADER_LENGTH - s->internal->init_num, 0);

        if (i <= 0) {

          s->internal->rwstate = SSL_READING;

          return i;

        }

        s->internal->init_num += i;

      }

      skip_message = 0;

      if (!s->server && 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->internal->init_num = 0;

          skip_message = 1;

          ssl_msg_callback(s, 0,

              SSL3_RT_HANDSHAKE, p,

              SSL3_HM_HEADER_LENGTH);

        }

      }

    } while (skip_message);

    if ((mt >= 0) && (*p != mt)) {

      al = SSL_AD_UNEXPECTED_MESSAGE;

      SSLerror(s, SSL_R_UNEXPECTED_MESSAGE);

      goto fatal_err;

    }

    CBS_init(&cbs, p, SSL3_HM_HEADER_LENGTH);

    if (!CBS_get_u8(&cbs, &u8) ||

        !CBS_get_u24(&cbs, &l)) {

      SSLerror(s, ERR_R_BUF_LIB);

      goto err;

    }

    s->s3->hs.tls12.message_type = u8;

    if (l > (unsigned long)max) {

      al = SSL_AD_ILLEGAL_PARAMETER;

      SSLerror(s, SSL_R_EXCESSIVE_MESSAGE_SIZE);

      goto fatal_err;

    }

    if (l && !BUF_MEM_grow_clean(s->internal->init_buf,

        l + SSL3_HM_HEADER_LENGTH)) {

      SSLerror(s, ERR_R_BUF_LIB);

      goto err;

    }

    s->s3->hs.tls12.message_size = l;

    s->s3->hs.state = stn;

    s->internal->init_msg = s->internal->init_buf->data +

        SSL3_HM_HEADER_LENGTH;

    s->internal->init_num = 0;

  }

  /* next state (stn) */

  p = s->internal->init_msg;

  n = s->s3->hs.tls12.message_size - s->internal->init_num;

  while (n > 0) {

    i = s->method->ssl_read_bytes(s, SSL3_RT_HANDSHAKE,

        &p[s->internal->init_num], n, 0);

    if (i <= 0) {

      s->internal->rwstate = SSL_READING;

      return i;

    }

    s->internal->init_num += i;

    n -= i;

  }

  /* Feed this message into MAC computation. */

  if (s->internal->mac_packet) {

    tls1_transcript_record(s, (unsigned char *)s->internal->init_buf->data,

        s->internal->init_num + SSL3_HM_HEADER_LENGTH);

    ssl_msg_callback(s, 0, SSL3_RT_HANDSHAKE,

        s->internal->init_buf->data,

        (size_t)s->internal->init_num + SSL3_HM_HEADER_LENGTH);

  }

  return 1;

 fatal_err:

  ssl3_send_alert(s, SSL3_AL_FATAL, al);

 err:

  return -1;

}

int

ssl_cert_type(EVP_PKEY *pkey)

{

  if (pkey == NULL)

    return -1;

  switch (EVP_PKEY_id(pkey)) {

  case EVP_PKEY_EC:

    return SSL_PKEY_ECC;

  case NID_id_GostR3410_2001:

  case NID_id_GostR3410_2001_cc:

    return SSL_PKEY_GOST01;

  case EVP_PKEY_RSA:

    return SSL_PKEY_RSA;

  }

  return -1;

}

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);

}

int

ssl3_setup_init_buffer(SSL *s)

{

  BUF_MEM *buf = NULL;

  if (s->internal->init_buf != NULL)

    return (1);

  if ((buf = BUF_MEM_new()) == NULL)

    goto err;

  if (!BUF_MEM_grow(buf, SSL3_RT_MAX_PLAIN_LENGTH))

    goto err;

  s->internal->init_buf = buf;

  return (1);

 err:

  BUF_MEM_free(buf);

  return (0);

}

void

ssl3_release_init_buffer(SSL *s)

{

  BUF_MEM_free(s->internal->init_buf);

  s->internal->init_buf = NULL;

  s->internal->init_msg = NULL;

  s->internal->init_num = 0;

  s->internal->init_off = 0;

}

int

ssl3_setup_read_buffer(SSL *s)

{

  unsigned char *p;

  size_t len, align, headerlen;

  if (SSL_is_dtls(s))

    headerlen = DTLS1_RT_HEADER_LENGTH;

  else

    headerlen = SSL3_RT_HEADER_LENGTH;

  align = (-SSL3_RT_HEADER_LENGTH) & (SSL3_ALIGN_PAYLOAD - 1);

  if (s->s3->rbuf.buf == NULL) {

    len = SSL3_RT_MAX_PLAIN_LENGTH +

        SSL3_RT_MAX_ENCRYPTED_OVERHEAD + headerlen + align;

    if ((p = calloc(1, len)) == NULL)

      goto err;

    s->s3->rbuf.buf = p;

    s->s3->rbuf.len = len;

  }

  s->internal->packet = s->s3->rbuf.buf;

  return 1;

 err:

  SSLerror(s, ERR_R_MALLOC_FAILURE);

  return 0;

}

int

ssl3_setup_write_buffer(SSL *s)

{

  unsigned char *p;

  size_t len, align, headerlen;

  if (SSL_is_dtls(s))

    headerlen = DTLS1_RT_HEADER_LENGTH + 1;

  else

    headerlen = SSL3_RT_HEADER_LENGTH;

  align = (-SSL3_RT_HEADER_LENGTH) & (SSL3_ALIGN_PAYLOAD - 1);

  if (s->s3->wbuf.buf == NULL) {

    len = s->max_send_fragment +

        SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD + headerlen + align;

    if (!(s->internal->options & SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS))

      len += headerlen + align +

          SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD;

    if ((p = calloc(1, len)) == NULL)

      goto err;

    s->s3->wbuf.buf = p;

    s->s3->wbuf.len = len;

  }

  return 1;

 err:

  SSLerror(s, 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;

}

void

ssl3_release_buffer(SSL3_BUFFER_INTERNAL *b)

{

  freezero(b->buf, b->len);

  b->buf = NULL;

  b->len = 0;

}

void

ssl3_release_read_buffer(SSL *s)

{

  ssl3_release_buffer(&s->s3->rbuf);

}

void

ssl3_release_write_buffer(SSL *s)

{

  ssl3_release_buffer(&s->s3->wbuf);

}