/* $OpenBSD: msg.c,v 1.22 2026/02/14 00:18:34 jsg Exp $ */

/*

 * Copyright (c) 2002 Markus Friedl.  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.

 *

 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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.

 */

#include "includes.h"

#include <sys/types.h>

#include <errno.h>

#include <string.h>

#include <unistd.h>

#include <stdarg.h>

#include "sshbuf.h"

#include "log.h"

#include "atomicio.h"

#include "msg.h"

#include "misc.h"

int

ssh_msg_send(int fd, u_char type, struct sshbuf *m)

{

  u_char buf[5];

  u_int mlen = sshbuf_len(m);

  debug3_f("type %u len %zu", (unsigned int)type & 0xff, sshbuf_len(m));

  put_u32(buf, mlen + 1);

  buf[4] = type;    /* 1st byte of payload is mesg-type */

  if (atomicio(vwrite, fd, buf, sizeof(buf)) != sizeof(buf)) {

    error_f("write: %s", strerror(errno));

    return (-1);

  }

  if (atomicio(vwrite, fd, sshbuf_mutable_ptr(m), mlen) != mlen) {

    error_f("write: %s", strerror(errno));

    return (-1);

  }

  debug3_f("done");

  return (0);

}

int

ssh_msg_recv(int fd, struct sshbuf *m)

{

  u_char buf[4], *p;

  u_int msg_len;

  int r;

  debug3("ssh_msg_recv entering");

  if (atomicio(read, fd, buf, sizeof(buf)) != sizeof(buf)) {

    if (errno != EPIPE)

      error_f("read header: %s", strerror(errno));

    return (-1);

  }

  msg_len = get_u32(buf);

  if (msg_len > sshbuf_max_size(m)) {

    error_f("read: bad msg_len %u", msg_len);

    return (-1);

  }

  sshbuf_reset(m);

  if ((r = sshbuf_reserve(m, msg_len, &p)) != 0) {

    error_fr(r, "reserve");

    return -1;

  }

  if (atomicio(read, fd, p, msg_len) != msg_len) {

    error_f("read: %s", strerror(errno));

    return (-1);

  }

  return (0);

}