GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: usr.sbin/dhcpd/icmp.c Lines: 0 56 0.0 %
Date: 2017-11-13 Branches: 0 22 0.0 %

Line Branch Exec Source
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/*	$OpenBSD: icmp.c,v 1.18 2017/02/13 23:04:05 krw Exp $ */
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/*
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 * Copyright (c) 1997, 1998 The Internet Software Consortium.
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 * All rights reserved.
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 *
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 * Redistribution and use in source and binary forms, with or without
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 * modification, are permitted provided that the following conditions
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 * are met:
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 *
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 * 1. Redistributions of source code must retain the above copyright
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 *    notice, this list of conditions and the following disclaimer.
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 * 2. Redistributions in binary form must reproduce the above copyright
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 *    notice, this list of conditions and the following disclaimer in the
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 *    documentation and/or other materials provided with the distribution.
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 * 3. Neither the name of The Internet Software Consortium nor the names
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 *    of its contributors may be used to endorse or promote products derived
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 *    from this software without specific prior written permission.
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 *
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 * THIS SOFTWARE IS PROVIDED BY THE INTERNET SOFTWARE CONSORTIUM AND
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 * CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
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 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
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 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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 * DISCLAIMED.  IN NO EVENT SHALL THE INTERNET SOFTWARE CONSORTIUM OR
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 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
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 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
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 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
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 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
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 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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 * SUCH DAMAGE.
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 *
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 * This software has been written for the Internet Software Consortium
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 * by Ted Lemon <mellon@fugue.com> in cooperation with Vixie
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 * Enterprises.  To learn more about the Internet Software Consortium,
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 * see ``http://www.vix.com/isc''.  To learn more about Vixie
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 * Enterprises, see ``http://www.vix.com''.
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 */
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#include <sys/types.h>
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#include <sys/socket.h>
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#include <arpa/inet.h>
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#include <net/if.h>
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#include <netinet/ip.h>
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#include <netinet/ip_icmp.h>
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#include <netdb.h>
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#include <stdio.h>
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#include <string.h>
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#include <unistd.h>
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#include "dhcp.h"
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#include "tree.h"
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#include "dhcpd.h"
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#include "log.h"
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static int icmp_protocol_initialized;
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static int icmp_protocol_fd;
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/* Initialize the ICMP protocol. */
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void
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icmp_startup(int routep, void (*handler)(struct iaddr, u_int8_t *, int))
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{
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	struct protoent *proto;
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	int protocol = 1, state;
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	/* Only initialize icmp once. */
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	if (icmp_protocol_initialized)
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		fatalx("attempted to reinitialize icmp protocol");
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	icmp_protocol_initialized = 1;
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	/* Get the protocol number (should be 1). */
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	if ((proto = getprotobyname("icmp")) != NULL)
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		protocol = proto->p_proto;
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	/* Get a raw socket for the ICMP protocol. */
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	if ((icmp_protocol_fd = socket(AF_INET, SOCK_RAW, protocol)) == -1)
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		fatal("unable to create icmp socket");
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	/* Make sure it does routing... */
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	state = 0;
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	if (setsockopt(icmp_protocol_fd, SOL_SOCKET, SO_DONTROUTE,
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	    &state, sizeof(state)) == -1)
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		fatal("Unable to disable SO_DONTROUTE on ICMP socket");
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	add_protocol("icmp", icmp_protocol_fd, icmp_echoreply,
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	    (void *)handler);
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}
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int
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icmp_echorequest(struct iaddr *addr)
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{
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	struct sockaddr_in to;
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	struct icmp icmp;
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	int status;
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	if (!icmp_protocol_initialized)
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		fatalx("attempt to use ICMP protocol before initialization.");
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	memset(&to, 0, sizeof(to));
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	to.sin_len = sizeof to;
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	to.sin_family = AF_INET;
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	memcpy(&to.sin_addr, addr->iabuf, sizeof to.sin_addr);	/* XXX */
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	icmp.icmp_type = ICMP_ECHO;
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	icmp.icmp_code = 0;
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	icmp.icmp_cksum = 0;
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	icmp.icmp_seq = 0;
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	icmp.icmp_id = getpid() & 0xffff;
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	icmp.icmp_cksum = wrapsum(checksum((unsigned char *)&icmp,
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	    sizeof(icmp), 0));
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	/* Send the ICMP packet... */
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	status = sendto(icmp_protocol_fd, &icmp, sizeof(icmp), 0,
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	    (struct sockaddr *)&to, sizeof(to));
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	if (status == -1)
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		log_warn("icmp_echorequest %s", inet_ntoa(to.sin_addr));
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	if (status != sizeof icmp)
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		return 0;
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	return 1;
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}
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void
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icmp_echoreply(struct protocol *protocol)
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{
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	void (*handler)(struct iaddr, u_int8_t *, int);
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	struct sockaddr_in from;
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	u_int8_t icbuf[1500];
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	struct icmp *icfrom;
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	int status, len;
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	socklen_t salen;
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	struct iaddr ia;
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	salen = sizeof from;
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	status = recvfrom(protocol->fd, icbuf, sizeof(icbuf), 0,
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	    (struct sockaddr *)&from, &salen);
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	if (status == -1) {
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		log_warn("icmp_echoreply");
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		return;
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	}
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	/* Probably not for us. */
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	if (status < (sizeof(struct ip)) + (sizeof *icfrom))
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		return;
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	len = status - sizeof(struct ip);
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	icfrom = (struct icmp *)(icbuf + sizeof(struct ip));
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	/* Silently discard ICMP packets that aren't echoreplies. */
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	if (icfrom->icmp_type != ICMP_ECHOREPLY)
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		return;
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	/* If we were given a second-stage handler, call it. */
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	if (protocol->local) {
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		handler = ((void (*)(struct iaddr, u_int8_t *, int))
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		    protocol->local);
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		memcpy(ia.iabuf, &from.sin_addr, sizeof from.sin_addr);
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		ia.len = sizeof from.sin_addr;
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		(*handler)(ia, icbuf, len);
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	}
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}