From 6a00f7ecdd12dca8126b6674bf7f9ab7f36d591e Mon Sep 17 00:00:00 2001 From: Holger Weiss Date: Tue, 8 Jan 2008 01:51:14 +0000 Subject: [PATCH] Fix the handling of ICMP packets which are not echo replies (such as destination unreachable messages) or which are not directed at us. git-svn-id: https://nagiosplug.svn.sourceforge.net/svnroot/nagiosplug/nagiosplug/trunk@1896 f882894a-f735-0410-b71e-b25c423dba1c --- plugins-root/check_icmp.c | 31 +++++++++++++++---------------- 1 file changed, 15 insertions(+), 16 deletions(-) diff --git a/plugins-root/check_icmp.c b/plugins-root/check_icmp.c index c0b29f2..a5e898a 100644 --- a/plugins-root/check_icmp.c +++ b/plugins-root/check_icmp.c @@ -192,7 +192,7 @@ static void run_checks(void); static void set_source_ip(char *); static int add_target(char *); static int add_target_ip(char *, struct in_addr *); -static int handle_random_icmp(struct icmp *, struct sockaddr_in *); +static int handle_random_icmp(char *, struct sockaddr_in *); static unsigned short icmp_checksum(unsigned short *, int); static void finish(int); static void crash(const char *, ...); @@ -299,19 +299,18 @@ get_icmp_error_msg(unsigned char icmp_type, unsigned char icmp_code) } static int -handle_random_icmp(struct icmp *p, struct sockaddr_in *addr) +handle_random_icmp(char *packet, struct sockaddr_in *addr) { - struct icmp sent_icmp; + struct icmp p, sent_icmp; struct rta_host *host = NULL; - unsigned char *ptr; - if(p->icmp_type == ICMP_ECHO && p->icmp_id == pid) { + memcpy(&p, packet, sizeof(p)); + if(p.icmp_type == ICMP_ECHO && p.icmp_id == pid) { /* echo request from us to us (pinging localhost) */ return 0; } - ptr = (unsigned char *)p; - if(debug) printf("handle_random_icmp(%p, %p)\n", (void *)p, (void *)addr); + if(debug) printf("handle_random_icmp(%p, %p)\n", (void *)&p, (void *)addr); /* only handle a few types, since others can't possibly be replies to * us in a sane network (if it is anyway, it will be counted as lost @@ -323,15 +322,15 @@ handle_random_icmp(struct icmp *p, struct sockaddr_in *addr) * TIMXCEED actually sends a proper icmp response we will have passed * too many hops to have a hope of reaching it later, in which case it * indicates overconfidence in the network, poor routing or both. */ - if(p->icmp_type != ICMP_UNREACH && p->icmp_type != ICMP_TIMXCEED && - p->icmp_type != ICMP_SOURCEQUENCH && p->icmp_type != ICMP_PARAMPROB) + if(p.icmp_type != ICMP_UNREACH && p.icmp_type != ICMP_TIMXCEED && + p.icmp_type != ICMP_SOURCEQUENCH && p.icmp_type != ICMP_PARAMPROB) { return 0; } /* might be for us. At least it holds the original package (according * to RFC 792). If it isn't, just ignore it */ - memcpy(&sent_icmp, ptr + 28, sizeof(sent_icmp)); + memcpy(&sent_icmp, packet + 28, sizeof(sent_icmp)); if(sent_icmp.icmp_type != ICMP_ECHO || sent_icmp.icmp_id != pid || sent_icmp.icmp_seq >= targets) { @@ -343,7 +342,7 @@ handle_random_icmp(struct icmp *p, struct sockaddr_in *addr) host = table[sent_icmp.icmp_seq]; if(debug) { printf("Received \"%s\" from %s for ICMP ECHO sent to %s.\n", - get_icmp_error_msg(p->icmp_type, p->icmp_code), + get_icmp_error_msg(p.icmp_type, p.icmp_code), inet_ntoa(addr->sin_addr), host->name); } @@ -354,7 +353,7 @@ handle_random_icmp(struct icmp *p, struct sockaddr_in *addr) /* source quench means we're sending too fast, so increase the * interval and mark this packet lost */ - if(p->icmp_type == ICMP_SOURCEQUENCH) { + if(p.icmp_type == ICMP_SOURCEQUENCH) { pkt_interval *= pkt_backoff_factor; target_interval *= target_backoff_factor; } @@ -362,8 +361,8 @@ handle_random_icmp(struct icmp *p, struct sockaddr_in *addr) targets_down++; host->flags |= FLAG_LOST_CAUSE; } - host->icmp_type = p->icmp_type; - host->icmp_code = p->icmp_code; + host->icmp_type = p.icmp_type; + host->icmp_code = p.icmp_code; host->error_addr.s_addr = addr->sin_addr.s_addr; return 0; @@ -758,13 +757,13 @@ wait_for_reply(int sock, u_int t) memcpy(&icp, buf + hlen, sizeof(icp)); if(icp.icmp_id != pid) { - handle_random_icmp(&icp, &resp_addr); + handle_random_icmp(buf + hlen, &resp_addr); continue; } if(icp.icmp_type != ICMP_ECHOREPLY || icp.icmp_seq >= targets) { if(debug > 2) printf("not a proper ICMP_ECHOREPLY\n"); - handle_random_icmp(&icp, &resp_addr); + handle_random_icmp(buf + hlen, &resp_addr); continue; } -- 2.30.2