check_icmp: buffer offerflow (#1733)

* Fix different overflows

* Less includes

* Add testcases

* Remove unused variable

* Remove unused and commented includes

2 files changed, 43 insertions, 30 deletions

diff --git a/plugins-root/check_icmp.c b/plugins-root/check_icmp.c
index f97b0ed..6119823 100644
--- a/plugins-root/check_icmp.c
+++ b/plugins-root/check_icmp.c
@@ -50,19 +50,11 @@ const char *email = "devel@monitoring-plugins.org";
 #if HAVE_SYS_SOCKIO_H
 #include <sys/sockio.h>
 #endif
-#include <sys/ioctl.h>
+
 #include <sys/time.h>
-#include <sys/types.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <stdarg.h>
-#include <unistd.h>
-#include <stddef.h>
 #include <errno.h>
-#include <string.h>
+#include <signal.h>
 #include <ctype.h>
-#include <netdb.h>
-#include <sys/socket.h>
 #include <net/if.h>
 #include <netinet/in_systm.h>
 #include <netinet/in.h>
@@ -71,8 +63,6 @@ const char *email = "devel@monitoring-plugins.org";
 #include <netinet/ip_icmp.h>
 #include <netinet/icmp6.h>
 #include <arpa/inet.h>
-#include <signal.h>
-#include <float.h>
 
 
 /** sometimes undefined system macros (quite a few, actually) **/
@@ -207,7 +197,7 @@ static int add_target(char *);
 static int add_target_ip(char *, struct sockaddr_storage *);
 static int handle_random_icmp(unsigned char *, struct sockaddr_storage *);
 static void parse_address(struct sockaddr_storage *, char *, int);
-static unsigned short icmp_checksum(unsigned short *, int);
+static unsigned short icmp_checksum(uint16_t *, size_t);
 static void finish(int);
 static void crash(const char *, ...);
 
@@ -465,7 +455,6 @@ main(int argc, char **argv)
         /* Parse protocol arguments first */
         for(i = 1; i < argc; i++) {
                 while((arg = getopt(argc, argv, opts_str)) != EOF) {
-                        unsigned short size;
                         switch(arg) {
                         case '4':
                                 if (address_family != -1)
@@ -488,10 +477,10 @@ main(int argc, char **argv)
         /* Reset argument scanning */
         optind = 1;
 
+        unsigned short size;
         /* parse the arguments */
         for(i = 1; i < argc; i++) {
                 while((arg = getopt(argc, argv, opts_str)) != EOF) {
-                        unsigned short size;
                         switch(arg) {
                         case 'v':
                                 debug++;
@@ -720,7 +709,7 @@ main(int argc, char **argv)
 static void
 run_checks()
 {
-        u_int i, t, result;
+        u_int i, t;
         u_int final_wait, time_passed;
 
         /* this loop might actually violate the pkt_interval or target_interval
@@ -738,9 +727,9 @@ run_checks()
 
                         /* we're still in the game, so send next packet */
                         (void)send_icmp_ping(icmp_sock, table[t]);
-                        result = wait_for_reply(icmp_sock, target_interval);
+                        wait_for_reply(icmp_sock, target_interval);
                 }
-                result = wait_for_reply(icmp_sock, pkt_interval * targets);
+                wait_for_reply(icmp_sock, pkt_interval * targets);
         }
 
         if(icmp_pkts_en_route && targets_alive) {
@@ -760,7 +749,7 @@ run_checks()
                  * haven't yet */
                 if(debug) printf("Waiting for %u micro-seconds (%0.3f msecs)\n",
                                                  final_wait, (float)final_wait / 1000);
-                result = wait_for_reply(icmp_sock, final_wait);
+                wait_for_reply(icmp_sock, final_wait);
         }
 }
 
@@ -779,7 +768,7 @@ static int
 wait_for_reply(int sock, u_int t)
 {
         int n, hlen;
-        static unsigned char buf[4096];
+        static unsigned char buf[65536];
         struct sockaddr_storage resp_addr;
         union ip_hdr *ip;
         union icmp_packet packet;
@@ -916,9 +905,27 @@ wait_for_reply(int sock, u_int t)
                 if(debug) {
                         char address[INET6_ADDRSTRLEN];
                         parse_address(&resp_addr, address, sizeof(address));
-                        printf("%0.3f ms rtt from %s, outgoing ttl: %u, incoming ttl: %u, max: %0.3f, min: %0.3f\n",
-                                (float)tdiff / 1000, address,
-                                ttl, ip->ip.ip_ttl, (float)host->rtmax / 1000, (float)host->rtmin / 1000);
+
+                        switch(address_family) {
+                                case AF_INET: {
+                                        printf("%0.3f ms rtt from %s, outgoing ttl: %u, incoming ttl: %u, max: %0.3f, min: %0.3f\n",
+                                                (float)tdiff / 1000,
+                                                address,
+                                                ttl,
+                                                ip->ip.ip_ttl,
+                                                (float)host->rtmax / 1000,
+                                                (float)host->rtmin / 1000);
+                                        break;
+                                          };
+                                case AF_INET6: {
+                                        printf("%0.3f ms rtt from %s, outgoing ttl: %u, max: %0.3f, min: %0.3f\n",
+                                                (float)tdiff / 1000,
+                                                address,
+                                                ttl,
+                                                (float)host->rtmax / 1000,
+                                                (float)host->rtmin / 1000);
+                                          };
+                           }
                 }
 
                 /* if we're in hostcheck mode, exit with limited printouts */
@@ -980,7 +987,7 @@ send_icmp_ping(int sock, struct rta_host *host)
                 icp->icmp_cksum = 0;
                 icp->icmp_id = htons(pid);
                 icp->icmp_seq = htons(host->id++);
-                icp->icmp_cksum = icmp_checksum((unsigned short*)buf, icmp_pkt_size);
+                icp->icmp_cksum = icmp_checksum((uint16_t*)buf, (size_t)icmp_pkt_size);
 
                 if (debug > 2)
                         printf("Sending ICMP echo-request of len %lu, id %u, seq %u, cksum 0x%X to host %s\n",
@@ -1517,18 +1524,19 @@ get_threshold(char *str, threshold *th)
 }
 
 unsigned short
-icmp_checksum(unsigned short *p, int n)
+icmp_checksum(uint16_t *p, size_t n)
 {
         unsigned short cksum;
         long sum = 0;
 
-        while(n > 2) {
-                sum += *p++;
-                n -= sizeof(unsigned short);
+        /* sizeof(uint16_t) == 2 */
+        while(n >= 2) {
+                sum += *(p++);
+                n -= 2;
         }
 
         /* mop up the occasional odd byte */
-        if(n == 1) sum += (unsigned char)*p;
+        if(n == 1) sum += *((uint8_t *)p -1);
 
         sum = (sum >> 16) + (sum & 0xffff);     /* add hi 16 to low 16 */
         sum += (sum >> 16);                     /* add carry */
diff --git a/plugins-root/t/check_icmp.t b/plugins-root/t/check_icmp.t
index 55edc31..f6aa681 100644
--- a/plugins-root/t/check_icmp.t
+++ b/plugins-root/t/check_icmp.t
@@ -12,7 +12,7 @@ my $allow_sudo = getTestParameter( "NP_ALLOW_SUDO",
         "no" );
 
 if ($allow_sudo eq "yes" or $> == 0) {
-        plan tests => 18;
+        plan tests => 20;
 } else {
         plan skip_all => "Need sudo to test check_icmp";
 }
@@ -89,3 +89,8 @@ $res = NPTest->testCmd(
 is( $res->return_code, 0, "IPv4 source_ip accepted" );
 like( $res->output, $successOutput, "Output OK" );
 
+$res = NPTest->testCmd(
+        "$sudo ./check_icmp -H $host_responsive -b 65507"
+        );
+is( $res->return_code, 0, "Try max paket size" );
+like( $res->output, $successOutput, "Output OK - Didn't overflow" );