Merge pull request #2029 from teg/network-fixes

Network fixes

11 files changed, 206 insertions, 149 deletions

diff --git a/src/libsystemd-network/dhcp-internal.h b/src/libsystemd-network/dhcp-internal.h
index a5daaa543a..7038212bcf 100644
--- a/src/libsystemd-network/dhcp-internal.h
+++ b/src/libsystemd-network/dhcp-internal.h
@@ -47,8 +47,7 @@ int dhcp_option_append(DHCPMessage *message, size_t size, size_t *offset, uint8_
 typedef int (*dhcp_option_cb_t)(uint8_t code, uint8_t len,
                                 const void *option, void *userdata);
 
-int dhcp_option_parse(DHCPMessage *message, size_t len,
-                      dhcp_option_cb_t cb, void *userdata);
+int dhcp_option_parse(DHCPMessage *message, size_t len, dhcp_option_cb_t cb, void *userdata, char **error_message);
 
 int dhcp_message_init(DHCPMessage *message, uint8_t op, uint32_t xid,
                       uint8_t type, uint16_t arp_type, size_t optlen,
diff --git a/src/libsystemd-network/dhcp-option.c b/src/libsystemd-network/dhcp-option.c
index a6c410ba91..1de7f3639c 100644
--- a/src/libsystemd-network/dhcp-option.c
+++ b/src/libsystemd-network/dhcp-option.c
@@ -24,6 +24,9 @@
 #include <stdio.h>
 #include <string.h>
 
+#include "alloc-util.h"
+#include "utf8.h"
+
 #include "dhcp-internal.h"
 
 static int option_append(uint8_t options[], size_t size, size_t *offset,
@@ -139,72 +142,84 @@ int dhcp_option_append(DHCPMessage *message, size_t size, size_t *offset,
 }
 
 static int parse_options(const uint8_t options[], size_t buflen, uint8_t *overload,
-                         uint8_t *message_type, dhcp_option_cb_t cb,
+                         uint8_t *message_type, char **error_message, dhcp_option_cb_t cb,
                          void *userdata) {
         uint8_t code, len;
+        const uint8_t *option;
         size_t offset = 0;
 
         while (offset < buflen) {
-                switch (options[offset]) {
-                case DHCP_OPTION_PAD:
-                        offset++;
+                code = options[offset ++];
 
-                        break;
+                switch (code) {
+                case DHCP_OPTION_PAD:
+                        continue;
 
                 case DHCP_OPTION_END:
                         return 0;
+                }
 
-                case DHCP_OPTION_MESSAGE_TYPE:
-                        if (buflen < offset + 3)
-                                return -ENOBUFS;
+                if (buflen < offset + 1)
+                        return -ENOBUFS;
+
+                len = options[offset ++];
 
-                        len = options[++offset];
+                if (buflen < offset + len)
+                        return -EINVAL;
+
+                option = &options[offset];
+
+                switch (code) {
+                case DHCP_OPTION_MESSAGE_TYPE:
                         if (len != 1)
                                 return -EINVAL;
 
                         if (message_type)
-                                *message_type = options[++offset];
-                        else
-                                offset++;
-
-                        offset++;
+                                *message_type = *option;
 
                         break;
 
-                case DHCP_OPTION_OVERLOAD:
-                        if (buflen < offset + 3)
-                                return -ENOBUFS;
-
-                        len = options[++offset];
-                        if (len != 1)
+                case DHCP_OPTION_ERROR_MESSAGE:
+                        if (len == 0)
                                 return -EINVAL;
 
-                        if (overload)
-                                *overload = options[++offset];
-                        else
-                                offset++;
+                        if (error_message) {
+                                _cleanup_free_ char *string = NULL;
 
-                        offset++;
+                                /* Accept a trailing NUL byte */
+                                if (memchr(option, 0, len - 1))
+                                        return -EINVAL;
 
-                        break;
+                                string = strndup((const char *) option, len);
+                                if (!string)
+                                        return -ENOMEM;
 
-                default:
-                        if (buflen < offset + 3)
-                                return -ENOBUFS;
+                                if (!ascii_is_valid(string))
+                                        return -EINVAL;
 
-                        code = options[offset];
-                        len = options[++offset];
+                                free(*error_message);
+                                *error_message = string;
+                                string = NULL;
+                        }
 
-                        if (buflen < ++offset + len)
+                        break;
+                case DHCP_OPTION_OVERLOAD:
+                        if (len != 1)
                                 return -EINVAL;
 
-                        if (cb)
-                                cb(code, len, &options[offset], userdata);
+                        if (overload)
+                                *overload = *option;
 
-                        offset += len;
+                        break;
+
+                default:
+                        if (cb)
+                                cb(code, len, option, userdata);
 
                         break;
                 }
+
+                offset += len;
         }
 
         if (offset < buflen)
@@ -213,8 +228,8 @@ static int parse_options(const uint8_t options[], size_t buflen, uint8_t *overlo
         return 0;
 }
 
-int dhcp_option_parse(DHCPMessage *message, size_t len,
-                      dhcp_option_cb_t cb, void *userdata) {
+int dhcp_option_parse(DHCPMessage *message, size_t len, dhcp_option_cb_t cb, void *userdata, char **_error_message) {
+        _cleanup_free_ char *error_message = NULL;
         uint8_t overload = 0;
         uint8_t message_type = 0;
         int r;
@@ -227,27 +242,29 @@ int dhcp_option_parse(DHCPMessage *message, size_t len,
 
         len -= sizeof(DHCPMessage);
 
-        r = parse_options(message->options, len, &overload, &message_type,
-                          cb, userdata);
+        r = parse_options(message->options, len, &overload, &message_type, &error_message, cb, userdata);
         if (r < 0)
                 return r;
 
         if (overload & DHCP_OVERLOAD_FILE) {
-                r = parse_options(message->file, sizeof(message->file),
-                                NULL, &message_type, cb, userdata);
+                r = parse_options(message->file, sizeof(message->file), NULL, &message_type, &error_message, cb, userdata);
                 if (r < 0)
                         return r;
         }
 
         if (overload & DHCP_OVERLOAD_SNAME) {
-                r = parse_options(message->sname, sizeof(message->sname),
-                                NULL, &message_type, cb, userdata);
+                r = parse_options(message->sname, sizeof(message->sname), NULL, &message_type, &error_message, cb, userdata);
                 if (r < 0)
                         return r;
         }
 
-        if (message_type)
-                return message_type;
+        if (message_type == 0)
+                return -ENOMSG;
+
+        if (_error_message && IN_SET(message_type, DHCP_NAK, DHCP_DECLINE)) {
+                *_error_message = error_message;
+                error_message = NULL;
+        }
 
-        return -ENOMSG;
+        return message_type;
 }
diff --git a/src/libsystemd-network/dhcp-protocol.h b/src/libsystemd-network/dhcp-protocol.h
index 05bb5ae493..f65529a00e 100644
--- a/src/libsystemd-network/dhcp-protocol.h
+++ b/src/libsystemd-network/dhcp-protocol.h
@@ -132,6 +132,7 @@ enum {
         DHCP_OPTION_MESSAGE_TYPE                = 53,
         DHCP_OPTION_SERVER_IDENTIFIER           = 54,
         DHCP_OPTION_PARAMETER_REQUEST_LIST      = 55,
+        DHCP_OPTION_ERROR_MESSAGE               = 56,
         DHCP_OPTION_MAXIMUM_MESSAGE_SIZE        = 57,
         DHCP_OPTION_RENEWAL_T1_TIME             = 58,
         DHCP_OPTION_REBINDING_T2_TIME           = 59,
diff --git a/src/libsystemd-network/icmp6-util.c b/src/libsystemd-network/icmp6-util.c
index 91308bf6c3..acad9d7d6a 100644
--- a/src/libsystemd-network/icmp6-util.c
+++ b/src/libsystemd-network/icmp6-util.c
@@ -47,17 +47,15 @@ int icmp6_bind_router_solicitation(int index) {
                 .ipv6mr_interface = index,
         };
         _cleanup_close_ int s = -1;
-        int r, zero = 0, hops = 255;
+        int r, zero = 0, one = 1, hops = 255;
 
-        s = socket(AF_INET6, SOCK_RAW | SOCK_CLOEXEC | SOCK_NONBLOCK,
-                   IPPROTO_ICMPV6);
+        s = socket(AF_INET6, SOCK_RAW | SOCK_CLOEXEC | SOCK_NONBLOCK, IPPROTO_ICMPV6);
         if (s < 0)
                 return -errno;
 
         ICMP6_FILTER_SETBLOCKALL(&filter);
         ICMP6_FILTER_SETPASS(ND_ROUTER_ADVERT, &filter);
-        r = setsockopt(s, IPPROTO_ICMPV6, ICMP6_FILTER, &filter,
-                       sizeof(filter));
+        r = setsockopt(s, IPPROTO_ICMPV6, ICMP6_FILTER, &filter, sizeof(filter));
         if (r < 0)
                 return -errno;
 
@@ -65,23 +63,23 @@ int icmp6_bind_router_solicitation(int index) {
            IPV6_PKTINFO socket option also applies for ICMPv6 multicast.
            Empirical experiments indicates otherwise and therefore an
            IPV6_MULTICAST_IF socket option is used here instead */
-        r = setsockopt(s, IPPROTO_IPV6, IPV6_MULTICAST_IF, &index,
-                       sizeof(index));
+        r = setsockopt(s, IPPROTO_IPV6, IPV6_MULTICAST_IF, &index, sizeof(index));
         if (r < 0)
                 return -errno;
 
-        r = setsockopt(s, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &zero,
-                       sizeof(zero));
+        r = setsockopt(s, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &zero, sizeof(zero));
         if (r < 0)
                 return -errno;
 
-        r = setsockopt(s, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &hops,
-                       sizeof(hops));
+        r = setsockopt(s, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &hops, sizeof(hops));
         if (r < 0)
                 return -errno;
 
-        r = setsockopt(s, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &mreq,
-                       sizeof(mreq));
+        r = setsockopt(s, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &mreq, sizeof(mreq));
+        if (r < 0)
+                return -errno;
+
+        r = setsockopt(s, SOL_IPV6, IPV6_RECVHOPLIMIT, &one, sizeof(one));
         if (r < 0)
                 return -errno;
 
@@ -101,25 +99,25 @@ int icmp6_send_router_solicitation(int s, const struct ether_addr *ether_addr) {
                 struct ether_addr rs_opt_mac;
         } _packed_ rs = {
                 .rs.nd_rs_type = ND_ROUTER_SOLICIT,
+                .rs_opt.nd_opt_type = ND_OPT_SOURCE_LINKADDR,
+                .rs_opt.nd_opt_len = 1,
         };
-        struct iovec iov[1] = {
-                { &rs, },
+        struct iovec iov = {
+                .iov_base = &rs,
+                .iov_len = sizeof(rs),
         };
         struct msghdr msg = {
                 .msg_name = &dst,
                 .msg_namelen = sizeof(dst),
-                .msg_iov = iov,
+                .msg_iov = &iov,
                 .msg_iovlen = 1,
         };
         int r;
 
-        if (ether_addr) {
-                memcpy(&rs.rs_opt_mac, ether_addr, ETH_ALEN);
-                rs.rs_opt.nd_opt_type = ND_OPT_SOURCE_LINKADDR;
-                rs.rs_opt.nd_opt_len = 1;
-                iov[0].iov_len = sizeof(rs);
-        } else
-                iov[0].iov_len = sizeof(rs.rs);
+        assert(s >= 0);
+        assert(ether_addr);
+
+        rs.rs_opt_mac = *ether_addr;
 
         r = sendmsg(s, &msg, 0);
         if (r < 0)
diff --git a/src/libsystemd-network/sd-dhcp-client.c b/src/libsystemd-network/sd-dhcp-client.c
index f689c59a1a..7deb00af9c 100644
--- a/src/libsystemd-network/sd-dhcp-client.c
+++ b/src/libsystemd-network/sd-dhcp-client.c
@@ -1082,7 +1082,7 @@ static int client_handle_offer(sd_dhcp_client *client, DHCPMessage *offer,
                         return r;
         }
 
-        r = dhcp_option_parse(offer, len, dhcp_lease_parse_options, lease);
+        r = dhcp_option_parse(offer, len, dhcp_lease_parse_options, lease, NULL);
         if (r != DHCP_OFFER) {
                 log_dhcp_client(client, "received message was not an OFFER, ignoring");
                 return -ENOMSG;
@@ -1121,7 +1121,7 @@ static int client_handle_forcerenew(sd_dhcp_client *client, DHCPMessage *force,
                                     size_t len) {
         int r;
 
-        r = dhcp_option_parse(force, len, NULL, NULL);
+        r = dhcp_option_parse(force, len, NULL, NULL, NULL);
         if (r != DHCP_FORCERENEW)
                 return -ENOMSG;
 
@@ -1133,6 +1133,7 @@ static int client_handle_forcerenew(sd_dhcp_client *client, DHCPMessage *force,
 static int client_handle_ack(sd_dhcp_client *client, DHCPMessage *ack,
                              size_t len) {
         _cleanup_dhcp_lease_unref_ sd_dhcp_lease *lease = NULL;
+        _cleanup_free_ char *error_message = NULL;
         int r;
 
         r = dhcp_lease_new(&lease);
@@ -1147,9 +1148,9 @@ static int client_handle_ack(sd_dhcp_client *client, DHCPMessage *ack,
                         return r;
         }
 
-        r = dhcp_option_parse(ack, len, dhcp_lease_parse_options, lease);
+        r = dhcp_option_parse(ack, len, dhcp_lease_parse_options, lease, &error_message);
         if (r == DHCP_NAK) {
-                log_dhcp_client(client, "NAK");
+                log_dhcp_client(client, "NAK: %s", strna(error_message));
                 return -EADDRNOTAVAIL;
         }
 
@@ -1513,9 +1514,8 @@ static int client_receive_message_udp(sd_event_source *s, int fd,
 
         r = ioctl(fd, FIONREAD, &buflen);
         if (r < 0)
-                return r;
-
-        if (buflen < 0)
+                return -errno;
+        else if (buflen < 0)
                 /* this can't be right */
                 return -EIO;
 
@@ -1525,26 +1525,28 @@ static int client_receive_message_udp(sd_event_source *s, int fd,
 
         len = read(fd, message, buflen);
         if (len < 0) {
-                log_dhcp_client(client, "could not receive message from UDP "
-                                "socket: %m");
-                return 0;
+                if (errno == EAGAIN || errno == EINTR)
+                        return 0;
+
+                log_dhcp_client(client, "Could not receive message from UDP socket: %m");
+                return -errno;
         } else if ((size_t)len < sizeof(DHCPMessage)) {
-                log_dhcp_client(client, "too small to be a DHCP message: ignoring");
+                log_dhcp_client(client, "Too small to be a DHCP message: ignoring");
                 return 0;
         }
 
         if (be32toh(message->magic) != DHCP_MAGIC_COOKIE) {
-                log_dhcp_client(client, "not a DHCP message: ignoring");
+                log_dhcp_client(client, "Not a DHCP message: ignoring");
                 return 0;
         }
 
         if (message->op != BOOTREPLY) {
-                log_dhcp_client(client, "not a BOOTREPLY message: ignoring");
+                log_dhcp_client(client, "Not a BOOTREPLY message: ignoring");
                 return 0;
         }
 
         if (message->htype != client->arp_type) {
-                log_dhcp_client(client, "packet type does not match client type");
+                log_dhcp_client(client, "Packet type does not match client type");
                 return 0;
         }
 
@@ -1558,13 +1560,12 @@ static int client_receive_message_udp(sd_event_source *s, int fd,
         }
 
         if (message->hlen != expected_hlen) {
-                log_dhcp_client(client, "unexpected packet hlen %d", message->hlen);
+                log_dhcp_client(client, "Unexpected packet hlen %d", message->hlen);
                 return 0;
         }
 
         if (memcmp(&message->chaddr[0], expected_chaddr, ETH_ALEN)) {
-                log_dhcp_client(client, "received chaddr does not match "
-                                "expected: ignoring");
+                log_dhcp_client(client, "Received chaddr does not match expected: ignoring");
                 return 0;
         }
 
@@ -1572,8 +1573,7 @@ static int client_receive_message_udp(sd_event_source *s, int fd,
             be32toh(message->xid) != client->xid) {
                 /* in BOUND state, we may receive FORCERENEW with xid set by server,
                    so ignore the xid in this case */
-                log_dhcp_client(client, "received xid (%u) does not match "
-                                "expected (%u): ignoring",
+                log_dhcp_client(client, "Received xid (%u) does not match expected (%u): ignoring",
                                 be32toh(message->xid), client->xid);
                 return 0;
         }
@@ -1602,9 +1602,8 @@ static int client_receive_message_raw(sd_event_source *s, int fd,
 
         r = ioctl(fd, FIONREAD, &buflen);
         if (r < 0)
-                return r;
-
-        if (buflen < 0)
+                return -errno;
+        else if (buflen < 0)
                 /* this can't be right */
                 return -EIO;
 
@@ -1617,9 +1616,12 @@ static int client_receive_message_raw(sd_event_source *s, int fd,
 
         len = recvmsg(fd, &msg, 0);
         if (len < 0) {
-                log_dhcp_client(client, "could not receive message from raw "
-                                "socket: %m");
-                return 0;
+                if (errno == EAGAIN || errno == EINTR)
+                        return 0;
+
+                log_dhcp_client(client, "Could not receive message from raw socket: %m");
+
+                return -errno;
         } else if ((size_t)len < sizeof(DHCPPacket))
                 return 0;
 
diff --git a/src/libsystemd-network/sd-dhcp-lease.c b/src/libsystemd-network/sd-dhcp-lease.c
index 8befedc500..fccdc01bc3 100644
--- a/src/libsystemd-network/sd-dhcp-lease.c
+++ b/src/libsystemd-network/sd-dhcp-lease.c
@@ -661,7 +661,7 @@ int dhcp_lease_parse_options(uint8_t code, uint8_t len, const void *option, void
                 break;
 
         default:
-                log_debug("Ignoring option DHCP option %i while parsing.", code);
+                log_debug("Ignoring option DHCP option %"PRIu8" while parsing.", code);
                 break;
         }
 
diff --git a/src/libsystemd-network/sd-dhcp-server.c b/src/libsystemd-network/sd-dhcp-server.c
index 277c88e2b9..587ff936ba 100644
--- a/src/libsystemd-network/sd-dhcp-server.c
+++ b/src/libsystemd-network/sd-dhcp-server.c
@@ -699,6 +699,7 @@ static int get_pool_offset(sd_dhcp_server *server, be32_t requested_ip) {
 int dhcp_server_handle_message(sd_dhcp_server *server, DHCPMessage *message,
                                size_t length) {
         _cleanup_dhcp_request_free_ DHCPRequest *req = NULL;
+        _cleanup_free_ char *error_message = NULL;
         DHCPLease *existing_lease;
         int type, r;
 
@@ -714,7 +715,7 @@ int dhcp_server_handle_message(sd_dhcp_server *server, DHCPMessage *message,
         if (!req)
                 return -ENOMEM;
 
-        type = dhcp_option_parse(message, length, parse_request, req);
+        type = dhcp_option_parse(message, length, parse_request, req, &error_message);
         if (type < 0)
                 return 0;
 
@@ -784,8 +785,7 @@ int dhcp_server_handle_message(sd_dhcp_server *server, DHCPMessage *message,
                 break;
         }
         case DHCP_DECLINE:
-                log_dhcp_server(server, "DECLINE (0x%x)",
-                                be32toh(req->message->xid));
+                log_dhcp_server(server, "DECLINE (0x%x): %s", be32toh(req->message->xid), strna(error_message));
 
                 /* TODO: make sure we don't offer this address again */
 
@@ -963,10 +963,10 @@ static int server_receive_message(sd_event_source *s, int fd,
 
         if (ioctl(fd, FIONREAD, &buflen) < 0)
                 return -errno;
-        if (buflen < 0)
+        else if (buflen < 0)
                 return -EIO;
 
-        message = malloc0(buflen);
+        message = malloc(buflen);
         if (!message)
                 return -ENOMEM;
 
@@ -974,9 +974,12 @@ static int server_receive_message(sd_event_source *s, int fd,
         iov.iov_len = buflen;
 
         len = recvmsg(fd, &msg, 0);
-        if (len < buflen)
-                return 0;
-        else if ((size_t)len < sizeof(DHCPMessage))
+        if (len < 0) {
+                if (errno == EAGAIN || errno == EINTR)
+                        return 0;
+
+                return -errno;
+        } else if ((size_t)len < sizeof(DHCPMessage))
                 return 0;
 
         CMSG_FOREACH(cmsg, &msg) {
diff --git a/src/libsystemd-network/sd-dhcp6-client.c b/src/libsystemd-network/sd-dhcp6-client.c
index 801331d270..36d909a4c5 100644
--- a/src/libsystemd-network/sd-dhcp6-client.c
+++ b/src/libsystemd-network/sd-dhcp6-client.c
@@ -895,7 +895,7 @@ static int client_receive_advertise(sd_dhcp6_client *client, DHCP6Message *adver
 static int client_receive_message(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
         sd_dhcp6_client *client = userdata;
         DHCP6_CLIENT_DONT_DESTROY(client);
-        _cleanup_free_ DHCP6Message *message;
+        _cleanup_free_ DHCP6Message *message = NULL;
         int r, buflen, len;
 
         assert(s);
@@ -903,18 +903,26 @@ static int client_receive_message(sd_event_source *s, int fd, uint32_t revents,
         assert(client->event);
 
         r = ioctl(fd, FIONREAD, &buflen);
-        if (r < 0 || buflen <= 0)
-                buflen = DHCP6_MIN_OPTIONS_SIZE;
+        if (r < 0)
+                return -errno;
+        else if (buflen < 0)
+                /* This really should not happen */
+                return -EIO;
 
-        message = malloc0(buflen);
+        message = malloc(buflen);
         if (!message)
                 return -ENOMEM;
 
         len = read(fd, message, buflen);
-        if ((size_t)len < sizeof(DHCP6Message)) {
-                log_dhcp6_client(client, "could not receive message from UDP socket: %m");
+        if (len < 0) {
+                if (errno == EAGAIN || errno == EINTR)
+                        return 0;
+
+                log_dhcp6_client(client, "Could not receive message from UDP socket: %m");
+
+                return -errno;
+        } else if ((size_t)len < sizeof(DHCP6Message))
                 return 0;
-        }
 
         switch(message->type) {
         case DHCP6_SOLICIT:
diff --git a/src/libsystemd-network/sd-ndisc.c b/src/libsystemd-network/sd-ndisc.c
index 713438f212..f2bce3b99f 100644
--- a/src/libsystemd-network/sd-ndisc.c
+++ b/src/libsystemd-network/sd-ndisc.c
@@ -418,8 +418,7 @@ static int ndisc_prefix_update(sd_ndisc *nd, ssize_t len,
         return 0;
 }
 
-static int ndisc_ra_parse(sd_ndisc *nd, struct nd_router_advert *ra,
-                          ssize_t len) {
+static int ndisc_ra_parse(sd_ndisc *nd, struct nd_router_advert *ra, ssize_t len) {
         void *opt;
         struct nd_opt_hdr *opt_hdr;
 
@@ -482,36 +481,79 @@ static int ndisc_ra_parse(sd_ndisc *nd, struct nd_router_advert *ra,
 static int ndisc_router_advertisment_recv(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
         _cleanup_free_ struct nd_router_advert *ra = NULL;
         sd_ndisc *nd = userdata;
-        int r, buflen = 0, pref, stateful;
-        union sockaddr_union router = {};
-        socklen_t router_len = sizeof(router);
+        union {
+                struct cmsghdr cmsghdr;
+                uint8_t buf[CMSG_LEN(sizeof(int))];
+        } control = {};
+        struct iovec iov = {};
+        union sockaddr_union sa = {};
+        struct msghdr msg = {
+                .msg_name = &sa.sa,
+                .msg_namelen = sizeof(sa),
+                .msg_iov = &iov,
+                .msg_iovlen = 1,
+                .msg_control = &control,
+                .msg_controllen = sizeof(control),
+        };
+        struct cmsghdr *cmsg;
         struct in6_addr *gw;
         unsigned lifetime;
         ssize_t len;
+        int r, pref, stateful, buflen = 0;
 
         assert(s);
         assert(nd);
         assert(nd->event);
 
         r = ioctl(fd, FIONREAD, &buflen);
-        if (r < 0 || buflen <= 0)
-                buflen = ICMP6_RECV_SIZE;
+        if (r < 0)
+                return -errno;
+        else if (buflen < 0)
+                /* This really should not happen */
+                return -EIO;
+
+        iov.iov_len = buflen;
 
-        ra = malloc(buflen);
+        ra = malloc(iov.iov_len);
         if (!ra)
                 return -ENOMEM;
 
-        len = recvfrom(fd, ra, buflen, 0, &router.sa, &router_len);
+        iov.iov_base = ra;
+
+        len = recvmsg(fd, &msg, 0);
         if (len < 0) {
+                if (errno == EAGAIN || errno == EINTR)
+                        return 0;
+
                 log_ndisc(nd, "Could not receive message from ICMPv6 socket: %m");
+                return -errno;
+        } else if ((size_t)len < sizeof(struct nd_router_advert)) {
                 return 0;
-        } else if (router_len == 0)
+        } else if (msg.msg_namelen == 0)
                 gw = NULL; /* only happens when running the test-suite over a socketpair */
-        else if (router_len != sizeof(router.in6)) {
-                log_ndisc(nd, "Received invalid source address size from ICMPv6 socket: %zu bytes", (size_t)router_len);
+        else if (msg.msg_namelen != sizeof(sa.in6)) {
+                log_ndisc(nd, "Received invalid source address size from ICMPv6 socket: %zu bytes", (size_t)msg.msg_namelen);
                 return 0;
         } else
-                gw = &router.in6.sin6_addr;
+                gw = &sa.in6.sin6_addr;
+
+        assert(!(msg.msg_flags & MSG_CTRUNC));
+        assert(!(msg.msg_flags & MSG_TRUNC));
+
+        CMSG_FOREACH(cmsg, &msg) {
+                if (cmsg->cmsg_level == SOL_IPV6 &&
+                    cmsg->cmsg_type == IPV6_HOPLIMIT &&
+                    cmsg->cmsg_len == CMSG_LEN(sizeof(int))) {
+                        int hops = *(int*)CMSG_DATA(cmsg);
+
+                        if (hops != 255) {
+                                log_ndisc(nd, "Received RA with invalid hop limit %d. Ignoring.", hops);
+                                return 0;
+                        }
+
+                        break;
+                }
+        }
 
         if (gw && !in_addr_is_link_local(AF_INET6, (const union in_addr_union*) gw)) {
                 _cleanup_free_ char *addr = NULL;
@@ -566,8 +608,6 @@ static int ndisc_router_advertisment_recv(sd_event_source *s, int fd, uint32_t r
 static int ndisc_router_solicitation_timeout(sd_event_source *s, uint64_t usec, void *userdata) {
         sd_ndisc *nd = userdata;
         uint64_t time_now, next_timeout;
-        struct ether_addr unset = { };
-        struct ether_addr *addr = NULL;
         int r;
 
         assert(s);
@@ -581,10 +621,7 @@ static int ndisc_router_solicitation_timeout(sd_event_source *s, uint64_t usec,
                         nd->callback(nd, SD_NDISC_EVENT_TIMEOUT, nd->userdata);
                 nd->state = NDISC_STATE_ADVERTISMENT_LISTEN;
         } else {
-                if (memcmp(&nd->mac_addr, &unset, sizeof(struct ether_addr)))
-                        addr = &nd->mac_addr;
-
-                r = icmp6_send_router_solicitation(nd->fd, addr);
+                r = icmp6_send_router_solicitation(nd->fd, &nd->mac_addr);
                 if (r < 0)
                         log_ndisc(nd, "Error sending Router Solicitation");
                 else {
diff --git a/src/libsystemd-network/test-dhcp-client.c b/src/libsystemd-network/test-dhcp-client.c
index 1200a7c251..4478147a83 100644
--- a/src/libsystemd-network/test-dhcp-client.c
+++ b/src/libsystemd-network/test-dhcp-client.c
@@ -223,7 +223,7 @@ int dhcp_network_send_udp_socket(int s, be32_t address, uint16_t port, const voi
 static int test_discover_message_verify(size_t size, struct DHCPMessage *dhcp) {
         int res;
 
-        res = dhcp_option_parse(dhcp, size, check_options, NULL);
+        res = dhcp_option_parse(dhcp, size, check_options, NULL, NULL);
         assert_se(res == DHCP_DISCOVER);
 
         if (verbose)
@@ -390,7 +390,7 @@ static int test_addr_acq_recv_request(size_t size, DHCPMessage *request) {
         uint8_t *msg_bytes = (uint8_t *)request;
         int res;
 
-        res = dhcp_option_parse(request, size, check_options, NULL);
+        res = dhcp_option_parse(request, size, check_options, NULL, NULL);
         assert_se(res == DHCP_REQUEST);
         assert_se(xid == request->xid);
 
@@ -420,7 +420,7 @@ static int test_addr_acq_recv_discover(size_t size, DHCPMessage *discover) {
         uint8_t *msg_bytes = (uint8_t *)discover;
         int res;
 
-        res = dhcp_option_parse(discover, size, check_options, NULL);
+        res = dhcp_option_parse(discover, size, check_options, NULL, NULL);
         assert_se(res == DHCP_DISCOVER);
 
         assert_se(msg_bytes[size - 1] == DHCP_OPTION_END);
diff --git a/src/libsystemd-network/test-dhcp-option.c b/src/libsystemd-network/test-dhcp-option.c
index 3607df63af..75d22c4df3 100644
--- a/src/libsystemd-network/test-dhcp-option.c
+++ b/src/libsystemd-network/test-dhcp-option.c
@@ -75,9 +75,8 @@ static const char *dhcp_type(int type) {
 static void test_invalid_buffer_length(void) {
         DHCPMessage message;
 
-        assert_se(dhcp_option_parse(&message, 0, NULL, NULL) == -EINVAL);
-        assert_se(dhcp_option_parse(&message, sizeof(DHCPMessage) - 1, NULL, NULL)
-               == -EINVAL);
+        assert_se(dhcp_option_parse(&message, 0, NULL, NULL, NULL) == -EINVAL);
+        assert_se(dhcp_option_parse(&message, sizeof(DHCPMessage) - 1, NULL, NULL, NULL) == -EINVAL);
 }
 
 static void test_message_init(void) {
@@ -101,7 +100,7 @@ static void test_message_init(void) {
         assert_se(magic[2] == 83);
         assert_se(magic[3] == 99);
 
-        assert_se(dhcp_option_parse(message, len, NULL, NULL) >= 0);
+        assert_se(dhcp_option_parse(message, len, NULL, NULL, NULL) >= 0);
 }
 
 static DHCPMessage *create_message(uint8_t *options, uint16_t optlen,
@@ -264,19 +263,12 @@ static void test_options(struct option_desc *desc) {
         buflen = sizeof(DHCPMessage) + optlen;
 
         if (!desc) {
-                assert_se((res = dhcp_option_parse(message, buflen,
-                                                test_options_cb,
-                                                NULL)) == -ENOMSG);
+                assert_se((res = dhcp_option_parse(message, buflen, test_options_cb, NULL, NULL)) == -ENOMSG);
         } else if (desc->success) {
-                assert_se((res = dhcp_option_parse(message, buflen,
-                                                test_options_cb,
-                                                desc)) >= 0);
-                assert_se(desc->pos == -1 && desc->filepos == -1 &&
-                                desc->snamepos == -1);
+                assert_se((res = dhcp_option_parse(message, buflen, test_options_cb, desc, NULL)) >= 0);
+                assert_se(desc->pos == -1 && desc->filepos == -1 && desc->snamepos == -1);
         } else
-                assert_se((res = dhcp_option_parse(message, buflen,
-                                                test_options_cb,
-                                                desc)) < 0);
+                assert_se((res = dhcp_option_parse(message, buflen, test_options_cb, desc, NULL)) < 0);
 
         if (verbose)
                 printf("DHCP type %s\n", dhcp_type(res));