network.c

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/*
 * Copyright (C) 1998  Mark Baysinger ([e-mail])
 * Copyright (C) 1998,1999,2000  Ross Combs ([e-mail])
 *
 * 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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */
#include "common/setup_before.h"
#ifdef HAVE_STRING_H
# include <string.h>
#else
# ifdef HAVE_STRINGS_H
#  include <strings.h>
# endif
#endif
#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif
#include <errno.h>
#include "compat/strerror.h"
#ifdef HAVE_SYS_TYPES_H
# include <sys/types.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
# include <sys/socket.h>
#endif
#include "compat/socket.h"
#include "compat/recv.h"
#include "compat/send.h"
#ifdef HAVE_NETINET_IN_H
# include <netinet/in.h>
#endif
#include "compat/netinet_in.h"
#include "compat/psock.h"
#include "common/packet.h"
#include "common/eventlog.h"
#include "common/field_sizes.h"
#include "common/network.h"
#include "common/setup_after.h"


extern int net_recv(int sock, void *buff, int len)
{
    int res;

    res = psock_recv(sock, buff, len, 0);
    if (res > 0) return res;
    if (!res) return -1;	/* connection closed */

    if (
#ifdef PSOCK_EINTR
	psock_errno()==PSOCK_EINTR ||
#endif
#ifdef PSOCK_EAGAIN
	psock_errno()==PSOCK_EAGAIN ||
#endif
#ifdef PSOCK_EWOULDBLOCK
	psock_errno()==PSOCK_EWOULDBLOCK ||
#endif
#ifdef PSOCK_ENOMEM
	psock_errno()==PSOCK_ENOMEM ||
#endif
	0) /* try later */
        return 0;

    if (
#ifdef PSOCK_ENOTCONN
	psock_errno()==PSOCK_ENOTCONN ||
#endif
#ifdef PSOCK_ECONNRESET
	psock_errno()==PSOCK_ECONNRESET ||
#endif
	0) {
/*	    eventlog(eventlog_level_debug,__FUNCTION__,"[%d] remote host closed connection (psock_recv: %s)",sock,pstrerror(psock_errno())); */
	    return -1; /* common error: close connection, but no message */
    }

    eventlog(eventlog_level_debug,__FUNCTION__,"[%d] receive error (closing connection) (psock_recv: %s)",sock,pstrerror(psock_errno()));
    return -1;
}

extern int net_recv_packet(int sock, t_packet * packet, unsigned int * currsize)
{
    int          addlen;
    unsigned int header_size;
    void *       temp;
    
    if (!packet) {
	eventlog(eventlog_level_error,__FUNCTION__,"[%d] got NULL packet (closing connection)",sock);
	return -1;
    }

    if (!currsize) {
	eventlog(eventlog_level_error,__FUNCTION__,"[%d] got NULL currsize (closing connection)",sock);
	return -1;
    }
    
    if ((header_size = packet_get_header_size(packet))>=MAX_PACKET_SIZE) {
	eventlog(eventlog_level_error,__FUNCTION__,"[%d] could not determine header size (closing connection)",sock);
	return -1;
    }
    
    if (!(temp = packet_get_raw_data_build(packet,*currsize))) {
	eventlog(eventlog_level_error,__FUNCTION__,"[%d] could not obtain raw data pointer at offset %u (closing connection)",sock,*currsize);
	return -1;
    }
    
    if (*currsize<header_size)
	addlen = net_recv(sock, temp, header_size-*currsize);
    else {
	unsigned int total_size=packet_get_size(packet);

	if (total_size<header_size) {
	    eventlog(eventlog_level_warn,__FUNCTION__,"[%d] corrupted packet received (total_size=%u currsize=%u) (closing connection)",sock,total_size,*currsize);
	    return -1;
	}

	if (*currsize>=total_size) {
	    eventlog(eventlog_level_warn,__FUNCTION__,"[%d] more data requested for already complete packet (total_size=%u currsize=%u) (closing connection)",sock,total_size,*currsize);
	    return -1;
	}

	addlen = net_recv(sock, temp, total_size-*currsize);
    }

    if (addlen<=0) return addlen;

    *currsize += addlen;
    
    if (*currsize>=header_size && *currsize==packet_get_size(packet))
	return 1;
    
    return 0;
}

extern int net_send(int sock, const void *buff, int len)
{
    int res;

    res = psock_send(sock, buff, len, 0);

    if (res > 0) return res;
    if (!res) return -1;

    if (
#ifdef PSOCK_EINTR
	psock_errno()==PSOCK_EINTR ||
#endif
#ifdef PSOCK_EAGAIN
	psock_errno()==PSOCK_EAGAIN ||
#endif
#ifdef PSOCK_EWOULDBLOCK
	psock_errno()==PSOCK_EWOULDBLOCK ||
#endif
#ifdef PSOCK_ENOBUFS
	psock_errno()==PSOCK_ENOBUFS ||
#endif
#ifdef PSOCK_ENOMEM
	psock_errno()==PSOCK_ENOMEM ||
#endif
	0)
	return 0; /* try again later */

    if (
#ifdef PSOCK_EPIPE
	psock_errno()!=PSOCK_EPIPE &&
#endif
#ifdef PSOCK_ECONNRESET
	psock_errno()!=PSOCK_ECONNRESET &&
#endif
	1) eventlog(eventlog_level_debug,__FUNCTION__,"[%d] could not send data (closing connection) (psock_send: %s)",sock,pstrerror(psock_errno()));

    return -1;
}

extern int net_send_packet(int sock, t_packet const * packet, unsigned int * currsize)
{
    unsigned int size;
    int          addlen;

    if (!packet) {
	eventlog(eventlog_level_error,__FUNCTION__,"[%d] got NULL packet (closing connection)",sock);
	return -1;
    }

    if (!currsize) {
	eventlog(eventlog_level_error,__FUNCTION__,"[%d] got NULL currsize (closing connection)",sock);
	return -1;
    }

    if ((size = packet_get_size(packet))<1) {
	eventlog(eventlog_level_error,__FUNCTION__,"[%d] packet to send is empty (skipping it)",sock);
	*currsize = 0;
	return 1;
    }

    addlen = net_send(sock,packet_get_raw_data_const(packet,*currsize),size-*currsize);

    if (addlen <= 0) return addlen;

    *currsize += addlen;
    /* sent all data in this packet? */
    if (size==*currsize)
    {
	*currsize = 0;
	return 1;
    }

    return 0;
}