/*

 *  This program is free software; you can redistribute it and/or modify

 *  it under the terms of the GNU General Public License as published by

 *  the Free Software Foundation; either version 2 of the License, or

 *  (at your option) any later version.

 *

 *  This program is distributed in the hope that it will be useful,

 *  but WITHOUT ANY WARRANTY; without even the implied warranty of

 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 *  GNU General Public License for more details.

 *

 *  You should have received a copy of the GNU General Public License

 *  along with this program; if not, write to the Free Software

 *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA

 */

/**

 * $Id: c8ca250f513459c54fa7978f6e18c21d3b328173 $

 *

 * @file protocols/radius/packet.c

 * @brief TCP-specific functions.

 *

 * @copyright (C) 2009 Dante http://dante.net

 */

RCSID("$Id: c8ca250f513459c54fa7978f6e18c21d3b328173 $")

#include <freeradius-devel/radius/radius.h>

#include <freeradius-devel/util/syserror.h>

#include "tcp.h"

fr_packet_t *fr_tcp_recv(int sockfd, int flags)

{

  fr_packet_t *packet = fr_packet_alloc(NULL, false);

  if (!packet) return NULL;

  packet->socket.fd = sockfd;

  if (fr_tcp_read_packet(packet, RADIUS_MAX_ATTRIBUTES, flags) != 1) {

    fr_packet_free(&packet);

    return NULL;

  }

  return packet;

}

/*

 *  Receives a packet, assuming that the fr_packet_t structure

 *  has been filled out already.

 *

 *  This ASSUMES that the packet is allocated && fields

 *  initialized.

 *

 *  This ASSUMES that the socket is marked as O_NONBLOCK, which

 *  the function above does set, if your system supports it.

 *

 *  Calling this function MAY change sockfd,

 *  if src_ipaddr.af == AF_UNSPEC.

 */

int fr_tcp_read_packet(fr_packet_t *packet, uint32_t max_attributes, bool require_message_authenticator)

{

  ssize_t len;

  /*

   *  No data allocated.  Read the 4-byte header into

   *  a temporary buffer.

   */

  if (!packet->data) {

    int packet_len;

    len = recv(packet->socket.fd, packet->vector + packet->data_len,

         4 - packet->data_len, 0);

    if (len == 0) return -2; /* clean close */

#ifdef ECONNRESET

    if ((len < 0) && (errno == ECONNRESET)) { /* forced */

      return -2;

    }

#endif

    if (len < 0) {

      fr_strerror_printf("Error receiving packet: %s", fr_syserror(errno));

      return -1;

    }

    packet->data_len += len;

    if (packet->data_len < 4) { /* want more data */

      return 0;

    }

    packet_len = fr_nbo_to_uint16(packet->vector + 2);

    if (packet_len < RADIUS_HEADER_LENGTH) {

      fr_strerror_const("Discarding packet: Smaller than RFC minimum of 20 bytes");

      return -1;

    }

    /*

     *  If the packet is too big, then the socket is bad.

     */

    if (packet_len > MAX_PACKET_LEN) {

      fr_strerror_const("Discarding packet: Larger than RFC limitation of 4096 bytes");

      return -1;

    }

    packet->data = talloc_array(packet, uint8_t, packet_len);

    if (!packet->data) {

      fr_strerror_const("Out of memory");

      return -1;

    }

    packet->data_len = packet_len;

    packet->partial = 4;

    memcpy(packet->data, packet->vector, 4);  //-V512

  }

  /*

   *  Try to read more data.

   */

  len = recv(packet->socket.fd, packet->data + packet->partial,

       packet->data_len - packet->partial, 0);

  if (len == 0) return -2; /* clean close */

#ifdef ECONNRESET

  if ((len < 0) && (errno == ECONNRESET)) { /* forced */

    return -2;

  }

#endif

  if (len < 0) {

    fr_strerror_printf("Error receiving packet: %s", fr_syserror(errno));

    return -1;

  }

  packet->partial += len;

  if (packet->partial < packet->data_len) {

    return 0;

  }

  /*

   *  See if it's a well-formed RADIUS packet.

   */

  if (!fr_packet_ok(packet, max_attributes, require_message_authenticator, NULL)) {

    return -1;

  }

  if (fr_debug_lvl) {

    char ip_buf[INET6_ADDRSTRLEN], buffer[256];

    if (packet->socket.inet.src_ipaddr.af != AF_UNSPEC) {

      inet_ntop(packet->socket.inet.src_ipaddr.af, &packet->socket.inet.src_ipaddr.addr, ip_buf, sizeof(ip_buf));

      snprintf(buffer, sizeof(buffer), "host %s port %d", ip_buf, packet->socket.inet.src_port);

    } else {

      snprintf(buffer, sizeof(buffer), "socket %d", packet->socket.fd);

    }

  }

  packet->timestamp = fr_time();

  return 1;   /* done reading the packet */

}