Merge branch 'collectd-4.10' into collectd-5.0

[collectd.git] / src / utils_dns.c

diff --git a/src/utils_dns.c b/src/utils_dns.c
index 2899bd4..80a2ee5 100644 (file)
--- a/src/utils_dns.c
+++ b/src/utils_dns.c
@@ -45,6 +45,12 @@
 #if HAVE_NETINET_IN_H
 # include <netinet/in.h>
 #endif
+#if HAVE_NETINET_IP6_H
+# include <netinet/ip6.h>
+#endif
+#if HAVE_NETINET_IP_COMPAT_H
+# include <netinet/ip_compat.h>
+#endif
 #if HAVE_ARPA_INET_H
 # include <arpa/inet.h>
 #endif
@@ -291,13 +297,18 @@ rfc1035NameUnpack(const char *buf, size_t sz, off_t * off, char *name, size_t ns
     off_t no = 0;
     unsigned char c;
     size_t len;
-    assert(ns > 0);
+    static int loop_detect = 0;
+    if (loop_detect > 2)
+       return 4;               /* compression loop */
+    if (ns <= 0)
+       return 4;               /* probably compression loop */
     do {
        if ((*off) >= sz)
            break;
        c = *(buf + (*off));
        if (c > 191) {
            /* blasted compression */
+           int rc;
            unsigned short s;
            off_t ptr;
            memcpy(&s, buf + (*off), sizeof(s));
@@ -305,18 +316,23 @@ rfc1035NameUnpack(const char *buf, size_t sz, off_t * off, char *name, size_t ns
            (*off) += sizeof(s);
            /* Sanity check */
            if ((*off) >= sz)
-               return 1;
+               return 1;       /* message too short */
            ptr = s & 0x3FFF;
            /* Make sure the pointer is inside this message */
            if (ptr >= sz)
-               return 2;
-           return rfc1035NameUnpack(buf, sz, &ptr, name + no, ns - no);
+               return 2;       /* bad compression ptr */
+           if (ptr < DNS_MSG_HDR_SZ)
+               return 2;       /* bad compression ptr */
+           loop_detect++;
+           rc = rfc1035NameUnpack(buf, sz, &ptr, name + no, ns - no);
+           loop_detect--;
+           return rc;
        } else if (c > RFC1035_MAXLABELSZ) {
            /*
             * "(The 10 and 01 combinations are reserved for future use.)"
             */
+           return 3;           /* reserved label/compression flags */
            break;
-           return 3;
        } else {
            (*off)++;
            len = (size_t) c;
@@ -324,15 +340,18 @@ rfc1035NameUnpack(const char *buf, size_t sz, off_t * off, char *name, size_t ns
                break;
            if (len > (ns - 1))
                len = ns - 1;
-           if ((*off) + len > sz)      /* message is too short */
-               return 4;
+           if ((*off) + len > sz)
+               return 4;       /* message is too short */
+           if (no + len + 1 > ns)
+               return 5;       /* qname would overflow name buffer */
            memcpy(name + no, buf + (*off), len);
            (*off) += len;
            no += len;
            *(name + (no++)) = '.';
        }
     } while (c > 0);
-    *(name + no - 1) = '\0';
+    if (no > 0)
+       *(name + no - 1) = '\0';
     /* make sure we didn't allow someone to overflow the name buffer */
     assert(no <= ns);
     return 0;
@@ -345,10 +364,10 @@ handle_dns(const char *buf, int len)
     uint16_t us;
     off_t offset;
     char *t;
-    int x;
+    int status;
 
     /* The DNS header is 12 bytes long */
-    if (len < 12)
+    if (len < DNS_MSG_HDR_SZ)
        return 0;
 
     memcpy(&us, buf + 0, 2);
@@ -379,11 +398,15 @@ handle_dns(const char *buf, int len)
     memcpy(&us, buf + 10, 2);
     qh.arcount = ntohs(us);
 
-    offset = 12;
+    offset = DNS_MSG_HDR_SZ;
     memset(qh.qname, '\0', MAX_QNAME_SZ);
-    x = rfc1035NameUnpack(buf, len, &offset, qh.qname, MAX_QNAME_SZ);
-    if (0 != x)
+    status = rfc1035NameUnpack(buf, len, &offset, qh.qname, MAX_QNAME_SZ);
+    if (status != 0)
+    {
+       INFO ("utils_dns: handle_dns: rfc1035NameUnpack failed "
+               "with status %i.", status);
        return 0;
+    }
     if ('\0' == qh.qname[0])
        sstrncpy (qh.qname, ".", sizeof (qh.qname));
     while ((t = strchr(qh.qname, '\n')))
@@ -424,6 +447,7 @@ handle_udp(const struct udphdr *udp, int len)
     return 1;
 }
 
+#if HAVE_NETINET_IP6_H
 static int
 handle_ipv6 (struct ip6_hdr *ipv6, int len)
 {
@@ -492,6 +516,16 @@ handle_ipv6 (struct ip6_hdr *ipv6, int len)
 
     return (1); /* Success */
 } /* int handle_ipv6 */
+/* #endif HAVE_NETINET_IP6_H */
+
+#else /* if !HAVE_NETINET_IP6_H */
+static int
+handle_ipv6 (__attribute__((unused)) void *pkg,
+       __attribute__((unused)) int len)
+{
+    return (0);
+}
+#endif /* !HAVE_NETINET_IP6_H */
 
 static int
 handle_ip(const struct ip *ip, int len)
@@ -502,7 +536,7 @@ handle_ip(const struct ip *ip, int len)
     struct in6_addr c_dst_addr;
 
     if (ip->ip_v == 6)
-       return (handle_ipv6 ((struct ip6_hdr *) ip, len));
+       return (handle_ipv6 ((void *) ip, len));
 
     in6_addr_from_buffer (&c_src_addr, &ip->ip_src.s_addr, sizeof (ip->ip_src.s_addr), AF_INET);
     in6_addr_from_buffer (&c_dst_addr, &ip->ip_dst.s_addr, sizeof (ip->ip_dst.s_addr), AF_INET);
@@ -600,7 +634,7 @@ handle_ether(const u_char * pkt, int len)
        return 0;
     memcpy(buf, pkt, len);
     if (ETHERTYPE_IPV6 == etype)
-       return (handle_ipv6 ((struct ip6_hdr *) buf, len));
+       return (handle_ipv6 ((void *) buf, len));
     else
        return handle_ip((struct ip *) buf, len);
 }
@@ -633,7 +667,7 @@ handle_linux_sll (const u_char *pkt, int len)
        return 0;
 
     if (ETHERTYPE_IPV6 == etype)
-       return (handle_ipv6 ((struct ip6_hdr *) pkt, len));
+       return (handle_ipv6 ((void *) pkt, len));
     else
        return handle_ip((struct ip *) pkt, len);
 }
@@ -644,10 +678,6 @@ void handle_pcap(u_char *udata, const struct pcap_pkthdr *hdr, const u_char *pkt
 {
     int status;
 
-    DEBUG ("handle_pcap (udata = %p, hdr = %p, pkt = %p): hdr->caplen = %i\n",
-                   (void *) udata, (void *) hdr, (void *) pkt,
-                   hdr->caplen);
-
     if (hdr->caplen < ETHER_HDR_LEN)
        return;
 
@@ -681,7 +711,7 @@ void handle_pcap(u_char *udata, const struct pcap_pkthdr *hdr, const u_char *pkt
            break;
 
        default:
-           ERROR ("handle_pcap: unsupported data link type %d\n",
+           ERROR ("handle_pcap: unsupported data link type %d",
                    pcap_datalink(pcap_obj));
            status = 0;
            break;