From 47fac6f603c236d7b149e0ec593269322572b352 Mon Sep 17 00:00:00 2001
From: Steven Barth <steven@midlink.org>
Date: Sun, 30 Mar 2014 19:51:56 +0200
Subject: [PATCH] Add initial support for CER-ID

---
 CMakeLists.txt |  4 ++++
 README         |  2 ++
 src/dhcpv6.c   | 13 ++++++++++++-
 src/odhcp6c.h  | 14 ++++++++++++++
 src/script.c   |  4 +++-
 5 files changed, 35 insertions(+), 2 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 47537e9..aedeebf 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -11,6 +11,10 @@ if(${EXT_PREFIX_CLASS})
 	add_definitions(-DEXT_PREFIX_CLASS=${EXT_PREFIX_CLASS})
 endif(${EXT_PREFIX_CLASS})
 
+if(${EXT_CER_ID})
+	add_definitions(-DEXT_CER_ID=${EXT_CER_ID})
+endif(${EXT_CER_ID})
+
 if(${EXT_BFD_PING})
 	add_definitions(-DEXT_BFD_PING)
 	set(BFD_SOURCE src/bfd.c)
diff --git a/README b/README
index 0b4cf9a..6f5c62c 100644
--- a/README
+++ b/README
@@ -28,6 +28,8 @@ especially routers. It compiles to only about 30 KB (-Os -s).
 	g) Information-Refresh Options
 	h) Configurable SOL_MAX_RT
 	i) DS-Lite AFTR-Name Option
+	j) Prefix Class (experimental)
+	k) CER-ID (experimental)
 
 4. Support for requesting and parsing Router Advertisements
 	a) parsing of prefixes, routes, MTU and RDNSS options
diff --git a/src/dhcpv6.c b/src/dhcpv6.c
index c87d289..afea77f 100644
--- a/src/dhcpv6.c
+++ b/src/dhcpv6.c
@@ -175,6 +175,9 @@ int init_dhcpv6(const char *ifname, unsigned int options, int sol_timeout)
 			htons(DHCPV6_OPT_INF_MAX_RT),
 #ifdef EXT_PREFIX_CLASS
 			htons(DHCPV6_OPT_PREFIX_CLASS),
+#endif
+#ifdef EXT_CER_ID
+			htons(DHCPV6_OPT_CER_ID),
 #endif
 		};
 		odhcp6c_add_state(STATE_ORO, oro, sizeof(oro));
@@ -1010,7 +1013,15 @@ static int dhcpv6_handle_reply(enum dhcpv6_msg orig, _unused const int rc,
 			if (inf_max_rt >= DHCPV6_INF_MAX_RT_MIN &&
 					inf_max_rt <= DHCPV6_INF_MAX_RT_MAX)
 				dhcpv6_retx[DHCPV6_MSG_INFO_REQ].max_timeo = inf_max_rt;
-		}else if (otype != DHCPV6_OPT_CLIENTID &&
+#ifdef EXT_CER_ID
+		} else if (otype == DHCPV6_OPT_CER_ID && olen == -4 +
+				sizeof(struct dhcpv6_cer_id)) {
+			struct dhcpv6_cer_id *cer_id = (void*)&odata[-4];
+			struct in6_addr any = IN6ADDR_ANY_INIT;
+			if (memcmp(&cer_id->addr, &any, sizeof(any)))
+				odhcp6c_add_state(STATE_CER, &cer_id->addr, sizeof(any));
+#endif
+		} else if (otype != DHCPV6_OPT_CLIENTID &&
 				otype != DHCPV6_OPT_SERVERID) {
 			odhcp6c_add_state(STATE_CUSTOM_OPTS,
 					&odata[-4], olen + 4);
diff --git a/src/odhcp6c.h b/src/odhcp6c.h
index f9a3fec..2bc289b 100644
--- a/src/odhcp6c.h
+++ b/src/odhcp6c.h
@@ -67,6 +67,10 @@ enum dhcvp6_opt {
 	/* draft-bhandari-dhc-class-based-prefix, not yet standardized */
 	DHCPV6_OPT_PREFIX_CLASS = EXT_PREFIX_CLASS,
 #endif
+#ifdef EXT_CER_ID
+	/* draft-donley-dhc-cer-id-option-03 */
+	DHCPV6_OPT_CER_ID = EXT_CER_ID,
+#endif
 };
 
 enum dhcpv6_opt_npt {
@@ -170,6 +174,15 @@ struct dhcpv6_auth_reconfigure {
 	uint8_t key[16];
 } _packed;
 
+struct dhcpv6_cer_id {
+	uint16_t type;
+	uint16_t len;
+	uint16_t reserved;
+	uint16_t auth_type;
+	uint8_t auth[16];
+	struct in6_addr addr;
+} _packed;
+
 
 #define dhcpv6_for_each_option(start, end, otype, olen, odata)\
 	for (uint8_t *_o = (uint8_t*)(start); _o + 4 <= (uint8_t*)(end) &&\
@@ -215,6 +228,7 @@ enum odhcp6c_state {
 	STATE_AFTR_NAME,
 	STATE_VENDORCLASS,
 	STATE_USERCLASS,
+	STATE_CER,
 	_STATE_MAX
 };
 
diff --git a/src/script.c b/src/script.c
index 61bab67..9089409 100644
--- a/src/script.c
+++ b/src/script.c
@@ -232,7 +232,7 @@ void script_delay_call(const char *status, int timeout)
 void script_call(const char *status)
 {
 	size_t dns_len, search_len, custom_len, sntp_ip_len, ntp_ip_len, ntp_dns_len;
-	size_t sip_ip_len, sip_fqdn_len, aftr_name_len;
+	size_t sip_ip_len, sip_fqdn_len, aftr_name_len, cer_len;
 
 	odhcp6c_expire();
 	if (delayed_call) {
@@ -249,6 +249,7 @@ void script_call(const char *status)
 	struct in6_addr *sip = odhcp6c_get_state(STATE_SIP_IP, &sip_ip_len);
 	uint8_t *sip_fqdn = odhcp6c_get_state(STATE_SIP_FQDN, &sip_fqdn_len);
 	uint8_t *aftr_name = odhcp6c_get_state(STATE_AFTR_NAME, &aftr_name_len);
+	struct in6_addr *cer = odhcp6c_get_state(STATE_CER, &cer_len);
 
 	size_t prefix_len, address_len, ra_pref_len, ra_route_len, ra_dns_len;
 	uint8_t *prefix = odhcp6c_get_state(STATE_IA_PD, &prefix_len);
@@ -268,6 +269,7 @@ void script_call(const char *status)
 		fqdn_to_env("SIP_DOMAIN", sip_fqdn, sip_fqdn_len);
 		fqdn_to_env("AFTR", aftr_name, aftr_name_len);
 		fqdn_to_ip_env("AFTR_IP", aftr_name, aftr_name_len);
+		ipv6_to_env("CER", cer, cer_len / sizeof(*cer));
 		bin_to_env(custom, custom_len);
 		entry_to_env("PREFIXES", prefix, prefix_len, ENTRY_PREFIX);
 		entry_to_env("ADDRESSES", address, address_len, ENTRY_ADDRESS);
-- 
2.39.5