suppress ipv4mapped errors from logs.

git-svn-id: file:///svn/unbound/trunk@1570 be551aaa-1e26-0410-a405-d3ace91eadb9

doc/Changelog

@@ -1,3 +1,9 @@
+1 April 2009: Wouter
+	- suppress errors when trying to contact authority servers that gave
+	  ipv6 AAAA records for their nameservers with ipv4 mapped contents.
+	  Still tries to do so, could work when deployed in intranet.
+	  Higher verbosity shows the error.
+
 30 March 2009: Wouter
 	- Fixup LDFLAGS from libevent sourcedir compile configure restore.
 	- Fixup so no non-absolute rpaths are added.

testcode/unitmain.c

@@ -238,6 +238,29 @@ net_test()
 				(struct sockaddr_storage*)&b6, i, l6) == i);
 		}
 	}
+	/* test addr_is_ip4mapped */
+	if(1) {
+		struct sockaddr_storage a;
+		socklen_t l = (socklen_t)sizeof(a);
+		unit_assert(ipstrtoaddr("12.13.14.15", 53, &a, &l));
+		unit_assert(!addr_is_ip4mapped(&a, l));
+		unit_assert(ipstrtoaddr("fe80::217:31ff:fe91:df", 53, &a, &l));
+		unit_assert(!addr_is_ip4mapped(&a, l));
+		unit_assert(ipstrtoaddr("ffff::217:31ff:fe91:df", 53, &a, &l));
+		unit_assert(!addr_is_ip4mapped(&a, l));
+		unit_assert(ipstrtoaddr("::ffff:31ff:fe91:df", 53, &a, &l));
+		unit_assert(!addr_is_ip4mapped(&a, l));
+		unit_assert(ipstrtoaddr("::fffe:fe91:df", 53, &a, &l));
+		unit_assert(!addr_is_ip4mapped(&a, l));
+		unit_assert(ipstrtoaddr("::ffff:127.0.0.1", 53, &a, &l));
+		unit_assert(addr_is_ip4mapped(&a, l));
+		unit_assert(ipstrtoaddr("::ffff:127.0.0.2", 53, &a, &l));
+		unit_assert(addr_is_ip4mapped(&a, l));
+		unit_assert(ipstrtoaddr("::ffff:192.168.0.2", 53, &a, &l));
+		unit_assert(addr_is_ip4mapped(&a, l));
+		unit_assert(ipstrtoaddr("2::ffff:192.168.0.2", 53, &a, &l));
+		unit_assert(!addr_is_ip4mapped(&a, l));
+	}
 }
 
 #include "util/config_file.h"

util/net_help.c

@@ -474,3 +474,17 @@ addr_to_str(struct sockaddr_storage* addr, socklen_t addrlen,
 		snprintf(buf, len, "(inet_ntop_error)");
 	}
 }
+
+int 
+addr_is_ip4mapped(struct sockaddr_storage* addr, socklen_t addrlen)
+{
+	/* prefix for ipv4 into ipv6 mapping is ::ffff:x.x.x.x */
+	const uint8_t map_prefix[16] = 
+		{0,0,0,0,  0,0,0,0, 0,0,0xff,0xff, 0,0,0,0};
+	uint8_t* s;
+	if(!addr_is_ip6(addr, addrlen))
+		return 0;
+	/* s is 16 octet ipv6 address string */
+	s = (uint8_t*)&((struct sockaddr_in6*)addr)->sin6_addr;
+	return (memcmp(s, map_prefix, 12) == 0);
+}

util/net_help.h

@@ -269,4 +269,12 @@ int addr_in_common(struct sockaddr_storage* addr1, int net1,
 void addr_to_str(struct sockaddr_storage* addr, socklen_t addrlen,
 	char* buf, size_t len);
 
+/**
+ * See if sockaddr is an ipv6 mapped ipv4 address, ::ffff:0.0.0.0
+ * @param addr: address
+ * @param addrlen: length of address
+ * @return true if so
+ */
+int addr_is_ip4mapped(struct sockaddr_storage* addr, socklen_t addrlen);
+
 #endif /* NET_HELP_H */

util/netevent.c

@@ -254,6 +254,12 @@ comm_point_send_udp_msg(struct comm_point *c, ldns_buffer* packet,
 		if(errno == ENETUNREACH && verbosity < VERB_ALGO)
 			return 0;
 #endif
+		/* squelch errors where people deploy AAAA ::ffff:bla for
+		 * authority servers, which we try for intranets. */
+		if(errno == EINVAL && addr_is_ip4mapped(
+			(struct sockaddr_storage*)addr, addrlen) &&
+			verbosity < VERB_DETAIL)
+			return 0;
 #ifndef USE_WINSOCK
 		verbose(VERB_OPS, "sendto failed: %s", strerror(errno));
 #else

util/random.c

@@ -81,7 +81,7 @@ struct ub_randstate {
 /** Number of bytes to reseed after */
 #define REKEY_BYTES	(1 << 24)
 
-/** (re)setup system seed */
+/* (re)setup system seed */
 void
 ub_systemseed(unsigned int seed)
 {