dhcpv6-ia: fix dereference after freeing assignment
[project/odhcpd.git] / src / dhcpv6-ia.c
index df69759..4c077db 100644 (file)
 #include <arpa/inet.h>
 #include <sys/timerfd.h>
 
+#define ADDR_ENTRY_VALID_IA_ADDR(iface, i, m, addrs) \
+    ((iface)->managed == RELAYD_MANAGED_NO_AFLAG || (i) == (m) || \
+     (addrs)[(i)].prefix > 64)
+
 static void free_dhcpv6_assignment(struct dhcpv6_assignment *c);
 static void reconf_timer(struct uloop_timeout *event);
 static struct uloop_timeout reconf_event = {.cb = reconf_timer};
@@ -50,6 +54,7 @@ int setup_dhcpv6_ia_interface(struct interface *iface, bool enable)
 {
        if (!enable && iface->ia_assignments.next) {
                struct dhcpv6_assignment *c;
+
                while (!list_empty(&iface->ia_assignments)) {
                        c = list_first_entry(&iface->ia_assignments, struct dhcpv6_assignment, head);
                        free_dhcpv6_assignment(c);
@@ -103,7 +108,7 @@ int setup_dhcpv6_ia_interface(struct interface *iface, bool enable)
                        /* Infinite valid */
                        a->valid_until = 0;
 
-                       // Assign to all interfaces
+                       /* Assign to all interfaces */
                        struct dhcpv6_assignment *c;
                        list_for_each_entry(c, &iface->ia_assignments, head) {
                                if (c->length != 128 || c->assigned > a->assigned) {
@@ -259,7 +264,7 @@ void dhcpv6_write_statefile(void)
                                        char duidbuf[264];
                                        odhcpd_hexlify(duidbuf, c->clid_data, c->clid_len);
 
-                                       // iface DUID iaid hostname lifetime assigned length [addrs...]
+                                       /* iface DUID iaid hostname lifetime assigned length [addrs...] */
                                        int l = snprintf(leasebuf, sizeof(leasebuf), "# %s %s %x %s %ld %x %u ",
                                                        iface->ifname, duidbuf, ntohl(c->iaid),
                                                        (c->hostname ? c->hostname : "-"),
@@ -274,9 +279,9 @@ void dhcpv6_write_statefile(void)
                                        size_t m = elect_addr(addrs, addrlen);
 
                                        for (size_t i = 0; i < addrlen; ++i) {
-                                               if (!valid_addr(&addrs[i], now) || (!INFINITE_VALID(c->valid_until) && c->valid_until <= now) ||
-                                                               (iface->managed < RELAYD_MANAGED_NO_AFLAG && i != m &&
-                                                                               addrs[i].prefix <= 64))
+                                               if (!valid_addr(&addrs[i], now) ||
+                                                           (!INFINITE_VALID(c->valid_until) && c->valid_until <= now) ||
+                                                           !ADDR_ENTRY_VALID_IA_ADDR(iface, i, m, addrs))
                                                        continue;
 
                                                addr = addrs[i].addr;
@@ -319,7 +324,7 @@ void dhcpv6_write_statefile(void)
                                        char duidbuf[16];
                                        odhcpd_hexlify(duidbuf, c->hwaddr, sizeof(c->hwaddr));
 
-                                       // iface DUID iaid hostname lifetime assigned length [addrs...]
+                                       /* iface DUID iaid hostname lifetime assigned length [addrs...] */
                                        int l = snprintf(leasebuf, sizeof(leasebuf), "# %s %s ipv4 %s %ld %x 32 ",
                                                        iface->ifname, duidbuf,
                                                        (c->hostname ? c->hostname : "-"),
@@ -384,7 +389,7 @@ static void apply_lease(struct interface *iface, struct dhcpv6_assignment *a, bo
        }
 }
 
-// More data was received from TCP connection
+/* More data was received from TCP connection */
 static void managed_handle_pd_data(struct ustream *s, _unused int bytes_new)
 {
        struct dhcpv6_assignment *c = container_of(s, struct dhcpv6_assignment, managed_sock);
@@ -450,7 +455,7 @@ static void managed_handle_pd_data(struct ustream *s, _unused int bytes_new)
 
        if (first && c->managed_size == 0)
                free_dhcpv6_assignment(c);
-       else if (first)
+       else if (first && !(c->flags & OAF_STATIC))
                c->valid_until = now + 150;
 }
 
@@ -460,7 +465,9 @@ static void managed_handle_pd_done(struct ustream *s)
 {
        struct dhcpv6_assignment *c = container_of(s, struct dhcpv6_assignment, managed_sock);
 
-       c->valid_until = odhcpd_time() + 15;
+       if (!(c->flags & OAF_STATIC))
+               c->valid_until = odhcpd_time() + 15;
+
        c->managed_size = 0;
 
        if (c->accept_reconf)
@@ -484,7 +491,10 @@ static bool assign_pd(struct interface *iface, struct dhcpv6_assignment *assign)
                                        iaidbuf, assign->iaid, assign->length);
                        ustream_write_pending(&assign->managed_sock.stream);
                        assign->managed_size = -1;
-                       assign->valid_until = odhcpd_time() + 15;
+
+                       if (!(assign->flags & OAF_STATIC))
+                               assign->valid_until = odhcpd_time() + 15;
+
                        list_add(&assign->head, &iface->ia_assignments);
 
                        /* Wait initial period of up to 250ms for immediate assignment */
@@ -752,11 +762,9 @@ static size_t append_reply(uint8_t *buf, size_t buflen, uint16_t status,
                                        n.addr.s6_addr32[3] = htonl(a->assigned);
                                        size_t entrlen = sizeof(n) - 4;
 
-                                       if (iface->managed < RELAYD_MANAGED_NO_AFLAG && i != m &&
-                                                       addrs[i].prefix <= 64)
-                                               continue;
-
-                                       if (datalen + entrlen + 4 > buflen || a->assigned == 0)
+                                       if (!ADDR_ENTRY_VALID_IA_ADDR(iface, i, m, addrs) ||
+                                                       a->assigned == 0 ||
+                                                       datalen + entrlen + 4 > buflen)
                                                continue;
 
                                        memcpy(buf + datalen, &n, sizeof(n));
@@ -920,6 +928,7 @@ static void dhcpv6_log(uint8_t msgtype, struct interface *iface, time_t now,
                struct odhcpd_ipaddr *addrs = (a->managed) ? a->managed : iface->ia_addr;
                size_t addrlen = (a->managed) ? (size_t)a->managed_size : iface->ia_addr_len;
                size_t lbsize = 0;
+               size_t m = elect_addr(addrs, addrlen);
                char addrbuf[INET6_ADDRSTRLEN];
 
                for (size_t i = 0; i < addrlen; ++i) {
@@ -928,8 +937,13 @@ static void dhcpv6_log(uint8_t msgtype, struct interface *iface, time_t now,
 
                        struct in6_addr addr = addrs[i].addr;
                        int prefix = a->managed ? addrs[i].prefix : a->length;
-                       if (prefix == 128)
+                       if (prefix == 128) {
+                               if (!ADDR_ENTRY_VALID_IA_ADDR(iface, i, m, addrs) ||
+                                               a->assigned == 0)
+                                       continue;
+
                                addr.s6_addr32[3] = htonl(a->assigned);
+                       }
                        else
                                addr.s6_addr32[1] |= htonl(a->assigned);
 
@@ -1032,12 +1046,12 @@ ssize_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
                list_for_each_entry(c, &iface->ia_assignments, head) {
                        if (((c->clid_len == clid_len && !memcmp(c->clid_data, clid_data, clid_len)) ||
                                        (c->clid_len >= clid_len && !c->clid_data[0] && !c->clid_data[1]
-                                               && !memcmp(c->mac, mac, sizeof(mac)))) &&
+                                               && !memcmp(c->mac, mac, sizeof(mac)))) &&
                                        (c->iaid == ia->iaid || INFINITE_VALID(c->valid_until) || now < c->valid_until) &&
                                        ((is_pd && c->length <= 64) || (is_na && c->length == 128))) {
                                a = c;
 
-                               // Reset state
+                               /* Reset state */
                                apply_lease(iface, a, false);
                                memcpy(a->clid_data, clid_data, clid_len);
                                a->clid_len = clid_len;
@@ -1137,10 +1151,11 @@ ssize_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
                                a->accept_reconf = accept_reconf;
                                a->flags |= OAF_BOUND;
                                apply_lease(iface, a, true);
-                       } else if (!assigned && a && a->managed_size == 0)
+                       } else if (!assigned && a && a->managed_size == 0) {
                                /* Cleanup failed assignment */
                                free_dhcpv6_assignment(a);
-
+                               a = NULL;
+                       }
                } else if (hdr->msg_type == DHCPV6_MSG_RENEW ||
                                hdr->msg_type == DHCPV6_MSG_RELEASE ||
                                hdr->msg_type == DHCPV6_MSG_REBIND ||