dhcpv6: rework option passthrough logic

[project/odhcp6c.git] / src / ra.c

diff --git a/src/ra.c b/src/ra.c
index 89dc58b960b557b3e3a6d651b11b1a6a5fa49c7c..299762e57bcb0247fe88bf1baa6f755c84f37962 100644 (file)
--- a/src/ra.c
+++ b/src/ra.c
@@ -1,5 +1,6 @@
 /**
  * Copyright (C) 2012-2014 Steven Barth <steven@midlink.org>
+ * Copyright (C) 2017-2018 Hans Dedecker <dedeckeh@gmail.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License v2 as published by
@@ -47,7 +48,6 @@
 #include "odhcp6c.h"
 #include "ra.h"
 
-
 static bool nocarrier = false;
 
 static int sock = -1, rtnl = -1;
@@ -55,6 +55,8 @@ static int if_index = 0;
 static char if_name[IF_NAMESIZE] = {0};
 static volatile int rs_attempt = 0;
 static struct in6_addr lladdr = IN6ADDR_ANY_INIT;
+static unsigned int ra_options = 0;
+static unsigned int ra_holdoff_interval = 0;
 
 struct {
        struct icmp6_hdr hdr;
@@ -64,11 +66,14 @@ struct {
        .lladdr = {ND_OPT_SOURCE_LINKADDR, 1, {0}},
 };
 
-
 static void ra_send_rs(int signal __attribute__((unused)));
 
-int ra_init(const char *ifname, const struct in6_addr *ifid)
+int ra_init(const char *ifname, const struct in6_addr *ifid,
+               unsigned int options, unsigned int holdoff_interval)
 {
+       ra_options = options;
+       ra_holdoff_interval = holdoff_interval;
+
        const pid_t ourpid = getpid();
        sock = socket(AF_INET6, SOCK_RAW | SOCK_CLOEXEC, IPPROTO_ICMPV6);
        if (sock < 0)
@@ -140,7 +145,6 @@ int ra_init(const char *ifname, const struct in6_addr *ifid)
        return 0;
 }
 
-
 static void ra_send_rs(int signal __attribute__((unused)))
 {
        const struct sockaddr_in6 dest = {AF_INET6, 0, 0, ALL_IPV6_ROUTERS, if_index};
@@ -158,15 +162,14 @@ static void ra_send_rs(int signal __attribute__((unused)))
                alarm(4);
 }
 
-
 static int16_t pref_to_priority(uint8_t flags)
 {
        flags = (flags >> 3) & 0x03;
+
        return (flags == 0x0) ? 512 : (flags == 0x1) ? 384 :
                        (flags == 0x3) ? 640 : -1;
 }
 
-
 bool ra_link_up(void)
 {
        static bool firstcall = true;
@@ -175,12 +178,12 @@ bool ra_link_up(void)
                struct ifinfomsg msg;
                uint8_t pad[4000];
        } resp;
-
        bool ret = false;
        ssize_t read;
 
        do {
                read = recv(rtnl, &resp, sizeof(resp), MSG_DONTWAIT);
+
                if (read < 0 || !NLMSG_OK(&resp.hdr, (size_t)read) ||
                                resp.hdr.nlmsg_type != RTM_NEWLINK ||
                                resp.msg.ifi_index != if_index)
@@ -241,32 +244,40 @@ static bool ra_icmpv6_valid(struct sockaddr_in6 *source, int hlim, uint8_t *data
 int ra_conf_hoplimit(int newvalue)
 {
        static int value = 0;
+
        if (newvalue > 0)
                value = newvalue;
+
        return value;
 }
 
 int ra_conf_mtu(int newvalue)
 {
        static int value = 0;
+
        if (newvalue >= 1280 && newvalue <= 65535)
                value = newvalue;
+
        return value;
 }
 
 int ra_conf_reachable(int newvalue)
 {
        static int value = 0;
+
        if (newvalue > 0 && newvalue <= 3600000)
                value = newvalue;
+
        return value;
 }
 
 int ra_conf_retransmit(int newvalue)
 {
        static int value = 0;
+
        if (newvalue > 0 && newvalue <= 60000)
                value = newvalue;
+
        return value;
 }
 
@@ -346,9 +357,11 @@ bool ra_process(void)
                entry->priority = pref_to_priority(adv->nd_ra_flags_reserved);
                if (entry->priority < 0)
                        entry->priority = pref_to_priority(0);
+
                entry->valid = router_valid;
                entry->preferred = entry->valid;
-               changed |= odhcp6c_update_entry(STATE_RA_ROUTE, entry, 0, true);
+               changed |= odhcp6c_update_entry(STATE_RA_ROUTE, entry,
+                                               0, ra_holdoff_interval);
 
                // Parse hoplimit
                ra_conf_hoplimit(adv->nd_ra_curhoplimit);
@@ -378,7 +391,8 @@ bool ra_process(void)
                                        continue;
 
                                if (entry->priority > 0)
-                                       changed |= odhcp6c_update_entry(STATE_RA_ROUTE, entry, 0, true);
+                                       changed |= odhcp6c_update_entry(STATE_RA_ROUTE, entry,
+                                                                       0, ra_holdoff_interval);
                        } else if (opt->type == ND_OPT_PREFIX_INFORMATION && opt->len == 4) {
                                struct nd_opt_prefix_info *pinfo = (struct nd_opt_prefix_info*)opt;
                                entry->router = any;
@@ -395,7 +409,8 @@ bool ra_process(void)
                                        continue;
 
                                if (pinfo->nd_opt_pi_flags_reserved & ND_OPT_PI_FLAG_ONLINK)
-                                       changed |= odhcp6c_update_entry(STATE_RA_ROUTE, entry, 7200, true);
+                                       changed |= odhcp6c_update_entry(STATE_RA_ROUTE, entry,
+                                                                       7200, ra_holdoff_interval);
 
                                if (!(pinfo->nd_opt_pi_flags_reserved & ND_OPT_PI_FLAG_AUTO) ||
                                                pinfo->nd_opt_pi_prefix_len != 64)
@@ -404,7 +419,8 @@ bool ra_process(void)
                                entry->target.s6_addr32[2] = lladdr.s6_addr32[2];
                                entry->target.s6_addr32[3] = lladdr.s6_addr32[3];
 
-                               changed |= odhcp6c_update_entry(STATE_RA_PREFIX, entry, 7200, true);
+                               changed |= odhcp6c_update_entry(STATE_RA_PREFIX, entry,
+                                                               7200, ra_holdoff_interval);
                        } else if (opt->type == ND_OPT_RECURSIVE_DNS && opt->len > 2) {
                                entry->router = from.sin6_addr;
                                entry->priority = 0;
@@ -416,7 +432,8 @@ bool ra_process(void)
                                for (ssize_t i = 0; i < (opt->len - 1) / 2; ++i) {
                                        memcpy(&entry->target, &opt->data[6 + i * sizeof(entry->target)],
                                                        sizeof(entry->target));
-                                       changed |= odhcp6c_update_entry(STATE_RA_DNS, entry, 0, true);
+                                       changed |= odhcp6c_update_entry(STATE_RA_DNS, entry,
+                                                                       0, ra_holdoff_interval);
                                }
                        } else if (opt->type == ND_OPT_DNSSL && opt->len > 1) {
                                uint32_t *valid = (uint32_t*)&opt->data[2];
@@ -437,23 +454,29 @@ bool ra_process(void)
                                        if (entry->auxlen == 0)
                                                continue;
 
-                                       changed |= odhcp6c_update_entry(STATE_RA_SEARCH, entry, 0, true);
+                                       changed |= odhcp6c_update_entry(STATE_RA_SEARCH, entry,
+                                                                       0, ra_holdoff_interval);
                                        entry->auxlen = 0;
                                }
                        }
                }
 
-               int states[2] = {STATE_RA_DNS, STATE_RA_SEARCH};
-               for (size_t i = 0; i < 2; ++i) {
-                       size_t ra_dns_len;
-                       uint8_t *start = odhcp6c_get_state(states[i], &ra_dns_len);
-                       for (struct odhcp6c_entry *c = (struct odhcp6c_entry*)start;
-                                               (uint8_t*)c < &start[ra_dns_len] &&
-                                               (uint8_t*)odhcp6c_next_entry(c) <= &start[ra_dns_len];
-                                               c = odhcp6c_next_entry(c))
-                               if (IN6_ARE_ADDR_EQUAL(&c->router, &from.sin6_addr) &&
-                                               c->valid > router_valid)
-                                       c->valid = router_valid;
+               if (ra_options & RA_RDNSS_DEFAULT_LIFETIME) {
+                       int states[2] = {STATE_RA_DNS, STATE_RA_SEARCH};
+
+                       for (size_t i = 0; i < 2; ++i) {
+                               size_t ra_dns_len;
+                               uint8_t *start = odhcp6c_get_state(states[i], &ra_dns_len);
+
+                               for (struct odhcp6c_entry *c = (struct odhcp6c_entry*)start;
+                                                       (uint8_t*)c < &start[ra_dns_len] &&
+                                                       (uint8_t*)odhcp6c_next_entry(c) <= &start[ra_dns_len];
+                                                       c = odhcp6c_next_entry(c)) {
+                                       if (IN6_ARE_ADDR_EQUAL(&c->router, &from.sin6_addr) &&
+                                                       c->valid > router_valid)
+                                               c->valid = router_valid;
+                               }
+                       }
                }
        }