treewide: rework code to get rid of fixed IPv6 address arrays

[project/odhcpd.git] / src / router.c

diff --git a/src/router.c b/src/router.c
index f08a7b0..85ca6b0 100644 (file)
--- a/src/router.c
+++ b/src/router.c
@@ -38,7 +38,7 @@ static void sigusr1_refresh(int signal);
 static struct odhcpd_event router_event = {.uloop = {.fd = -1}, .handle_dgram = handle_icmpv6, };
 
 static FILE *fp_route = NULL;
-#define RA_IOV_LEN 6
+#define RA_IOV_LEN 7
 
 #define TIME_LEFT(t1, now) ((t1) != UINT32_MAX ? (t1) - (now) : UINT32_MAX)
 
@@ -275,7 +275,6 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
                struct nd_router_advert h;
                struct icmpv6_opt lladdr;
                struct nd_opt_mtu mtu;
-               struct nd_opt_prefix_info prefix[sizeof(iface->ia_addr) / sizeof(*iface->ia_addr)];
        } adv = {
                .h = {{.icmp6_type = ND_ROUTER_ADVERT, .icmp6_code = 0}, 0, 0},
                .lladdr = {ND_OPT_SOURCE_LINKADDR, 1, {0}},
@@ -302,7 +301,7 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
        odhcpd_get_mac(iface, adv.lladdr.data);
 
        // If not currently shutting down
-       struct odhcpd_ipaddr addrs[RELAYD_MAX_ADDRS];
+       struct odhcpd_ipaddr *addrs = NULL;
        ssize_t ipcnt = 0;
        uint32_t minvalid = UINT32_MAX;
        bool default_route = false;
@@ -310,8 +309,11 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
 
        // If not shutdown
        if (iface->timer_rs.cb) {
+               size_t size = sizeof(*addrs) * iface->ia_addr_len;
+               addrs = alloca(size);
+               memcpy(addrs, iface->ia_addr, size);
+
                ipcnt = iface->ia_addr_len;
-               memcpy(addrs, iface->ia_addr, ipcnt * sizeof(*addrs));
 
                // Check default route
                if (iface->default_router) {
@@ -323,14 +325,16 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
                        default_route = true;
        }
 
-       // Construct Prefix Information options
-       size_t cnt = 0;
 
        struct in6_addr dns_pref, *dns_addr = &dns_pref;
        size_t dns_cnt = 1;
 
        odhcpd_get_interface_dns_addr(iface, &dns_pref);
 
+       // Construct Prefix Information options
+       size_t pfxs_cnt = 0;
+       struct nd_opt_prefix_info *pfxs = NULL;
+
        for (ssize_t i = 0; i < ipcnt; ++i) {
                struct odhcpd_ipaddr *addr = &addrs[i];
                uint32_t preferred = 0;
@@ -346,18 +350,25 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
                }
 
                struct nd_opt_prefix_info *p = NULL;
-               for (size_t i = 0; i < cnt; ++i) {
-                       if (addr->prefix == adv.prefix[i].nd_opt_pi_prefix_len &&
-                                       !odhcpd_bmemcmp(&adv.prefix[i].nd_opt_pi_prefix,
+               for (size_t i = 0; i < pfxs_cnt; ++i) {
+                       if (addr->prefix == pfxs[i].nd_opt_pi_prefix_len &&
+                                       !odhcpd_bmemcmp(&pfxs[i].nd_opt_pi_prefix,
                                        &addr->addr, addr->prefix))
-                               p = &adv.prefix[i];
+                               p = &pfxs[i];
                }
 
                if (!p) {
-                       if (cnt >= ARRAY_SIZE(adv.prefix))
-                               break;
+                       struct nd_opt_prefix_info *tmp;
 
-                       p = &adv.prefix[cnt++];
+                       tmp = realloc(pfxs, sizeof(*pfxs) * (pfxs_cnt + 1));
+                       if (!tmp) {
+                               syslog(LOG_ERR, "Realloc failed for RA prefix option on interface %s", iface->ifname);
+                               continue;
+                       }
+
+                       pfxs = tmp;
+                       p = &pfxs[pfxs_cnt++];
+                       memset(p, 0, sizeof(*p));
                }
 
                if (addr->preferred > (uint32_t)now) {
@@ -428,8 +439,6 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
                uint32_t lifetime;
        } dns = {ND_OPT_RECURSIVE_DNS, (1 + (2 * dns_cnt)), 0, 0, 0};
 
-
-
        // DNS Search options
        uint8_t search_buf[256], *search_domain = iface->search;
        size_t search_len = iface->search_len, search_padded = 0;
@@ -471,7 +480,7 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
                uint8_t flags;
                uint32_t lifetime;
                uint32_t addr[4];
-       } routes[RELAYD_MAX_PREFIXES];
+       } *tmp, *routes = NULL;
 
        for (ssize_t i = 0; i < ipcnt; ++i) {
                struct odhcpd_ipaddr *addr = &addrs[i];
@@ -485,6 +494,15 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
                        addr->addr.s6_addr32[1] = 0;
                }
 
+               tmp = realloc(routes, sizeof(*routes) * (routes_cnt + 1));
+               if (!tmp) {
+                       syslog(LOG_ERR, "Realloc failed for RA route option on interface %s", iface->ifname);
+                       continue;
+               }
+
+               routes = tmp;
+
+               memset(&routes[routes_cnt], 0, sizeof(*routes));
                routes[routes_cnt].type = ND_OPT_ROUTE_INFO;
                routes[routes_cnt].len = sizeof(*routes) / 8;
                routes[routes_cnt].prefix = addr->dprefix;
@@ -512,8 +530,9 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
        };
 
        struct iovec iov[RA_IOV_LEN] = {
-                       {&adv, (uint8_t*)&adv.prefix[cnt] - (uint8_t*)&adv},
-                       {&routes, routes_cnt * sizeof(*routes)},
+                       {&adv, sizeof(adv)},
+                       {pfxs, pfxs_cnt * sizeof(*pfxs)},
+                       {routes, routes_cnt * sizeof(*routes)},
                        {&dns, (dns_cnt) ? sizeof(dns) : 0},
                        {dns_addr, dns_cnt * sizeof(*dns_addr)},
                        {search, search->len * 8},
@@ -526,6 +545,9 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
        odhcpd_send(router_event.uloop.fd,
                        &dest, iov, ARRAY_SIZE(iov), iface);
 
+       free(pfxs);
+       free(routes);
+
        return msecs;
 }