From: Hans Dedecker <dedeckeh@gmail.com>
Date: Wed, 16 Jan 2019 10:03:14 +0000 (+0100)
Subject: dhcpv6-ia: fix onlink IA check (FS#2060)
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=1893905f6a9b699ae0f1813670e93bf4ec3402e9;p=oweals%2Fodhcpd.git

dhcpv6-ia: fix onlink IA check (FS#2060)

Some DHCPv6 clients start sending SOLICIT messages without including either
an IA_NA or IA_PD and only start including an IA_NA or IA_PD in the REQUEST
message without including an IA_PREFIX or IA_ADDR as suboption. As a result
the check to verify if an IA_ADDR and/or IA_PREFIX is onlink fails.
Fix this by returning notonlink if an IA_PREFIX or IA_ADDR suboption is
present having an address/prefix not matching any of the addresses

Signed-off-by: Hans Dedecker <dedeckeh@gmail.com>
---

diff --git a/src/dhcpv6-ia.c b/src/dhcpv6-ia.c
index 415ec2a..c72c4b4 100644
--- a/src/dhcpv6-ia.c
+++ b/src/dhcpv6-ia.c
@@ -1104,7 +1104,7 @@ static bool dhcpv6_ia_on_link(const struct dhcpv6_ia_hdr *ia, struct dhcpv6_assi
 	time_t now = odhcpd_time();
 	uint8_t *odata, *end = ((uint8_t*)ia) + htons(ia->len) + 4;
 	uint16_t otype, olen;
-	bool onlink = false;
+	bool onlink = true;
 
 	dhcpv6_for_each_option((uint8_t*)&ia[1], end, otype, olen, odata) {
 		struct dhcpv6_ia_prefix *p = (struct dhcpv6_ia_prefix*)&odata[-4];
@@ -1114,7 +1114,7 @@ static bool dhcpv6_ia_on_link(const struct dhcpv6_ia_hdr *ia, struct dhcpv6_assi
 				(otype != DHCPV6_OPT_IA_ADDR || olen < sizeof(*n) - 4))
 			continue;
 
-		for (size_t i = 0; i < addrlen; ++i) {
+		for (size_t i = 0, onlink = false; i < addrlen; ++i) {
 			struct in6_addr addr = addrs[i].addr.in6;
 
 			if (!valid_addr(&addrs[i], now))