X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fresolve%2Fresolved-manager.c;h=319baf7887d84b0d210a621af005efb11b790d39;hp=ab504d0a758f73033255b106a22f4dbb4103a54c;hb=0f05c387597a93fa74cdf7d351fd255aca56026d;hpb=36f822c4bd077f9121757e24b6516e5c7ada63b5 diff --git a/src/resolve/resolved-manager.c b/src/resolve/resolved-manager.c index ab504d0a7..319baf788 100644 --- a/src/resolve/resolved-manager.c +++ b/src/resolve/resolved-manager.c @@ -21,7 +21,7 @@ #include #include -#include +#include #include #include #include @@ -29,11 +29,10 @@ #include "rtnl-util.h" #include "event-util.h" #include "network-util.h" -#include "sd-dhcp-lease.h" -#include "dhcp-lease-internal.h" #include "network-internal.h" #include "conf-parser.h" #include "socket-util.h" +#include "af-list.h" #include "resolved.h" #define SEND_TIMEOUT_USEC (200 * USEC_PER_MSEC) @@ -60,10 +59,10 @@ static int manager_process_link(sd_rtnl *rtnl, sd_rtnl_message *mm, void *userda switch (type) { - case RTM_NEWLINK: - if (!l) { - log_debug("Found link %i", ifindex); + case RTM_NEWLINK:{ + bool is_new = !l; + if (!l) { r = link_new(m, &l, ifindex); if (r < 0) goto fail; @@ -73,11 +72,15 @@ static int manager_process_link(sd_rtnl *rtnl, sd_rtnl_message *mm, void *userda if (r < 0) goto fail; + if (is_new) + log_debug("Found new link %i/%s", ifindex, l->name); + break; + } case RTM_DELLINK: if (l) { - log_debug("Removing link %i", l->ifindex); + log_debug("Removing link %i/%s", l->ifindex, l->name); link_free(l); } @@ -94,9 +97,8 @@ fail: static int manager_process_address(sd_rtnl *rtnl, sd_rtnl_message *mm, void *userdata) { Manager *m = userdata; union in_addr_union address; - unsigned char family; uint16_t type; - int r, ifindex; + int r, ifindex, family; LinkAddress *a; Link *l; @@ -282,7 +284,7 @@ static int manager_network_monitor_listen(Manager *m) { assert(m); - r = sd_network_monitor_new(NULL, &m->network_monitor); + r = sd_network_monitor_new(&m->network_monitor, NULL); if (r < 0) return r; @@ -311,7 +313,7 @@ static int parse_dns_server_string(Manager *m, const char *string) { FOREACH_WORD_QUOTED(word, length, string, state) { char buffer[length+1]; - unsigned family; + int family; union in_addr_union addr; memcpy(buffer, word, length); @@ -327,7 +329,7 @@ static int parse_dns_server_string(Manager *m, const char *string) { if (manager_find_dns_server(m, family, &addr)) continue; - r = dns_server_new(m, NULL, DNS_SERVER_SYSTEM, NULL, family, &addr); + r = dns_server_new(m, NULL, NULL, family, &addr); if (r < 0) return r; } @@ -392,11 +394,19 @@ int manager_new(Manager **ret) { return -ENOMEM; m->dns_ipv4_fd = m->dns_ipv6_fd = -1; + m->llmnr_ipv4_udp_fd = m->llmnr_ipv6_udp_fd = -1; + m->llmnr_ipv4_tcp_fd = m->llmnr_ipv6_tcp_fd = -1; - r = parse_dns_server_string(m, /* "172.31.0.125 2001:4860:4860::8888 2001:4860:4860::8889" */ DNS_SERVERS); + m->use_llmnr = true; + + r = parse_dns_server_string(m, DNS_SERVERS); if (r < 0) return r; + m->hostname = gethostname_malloc(); + if (!m->hostname) + return -ENOMEM; + r = sd_event_default(&m->event); if (r < 0) return r; @@ -406,7 +416,7 @@ int manager_new(Manager **ret) { sd_event_set_watchdog(m->event, true); - r = dns_scope_new(m, &m->unicast_scope, DNS_SCOPE_DNS); + r = dns_scope_new(m, &m->unicast_scope, NULL, DNS_PROTOCOL_DNS, AF_UNSPEC); if (r < 0) return r; @@ -422,6 +432,19 @@ int manager_new(Manager **ret) { if (r < 0) return r; + r = manager_llmnr_ipv4_udp_fd(m); + if (r < 0) + return r; + r = manager_llmnr_ipv6_udp_fd(m); + if (r < 0) + return r; + r = manager_llmnr_ipv4_tcp_fd(m); + if (r < 0) + return r; + r = manager_llmnr_ipv6_tcp_fd(m); + if (r < 0) + return r; + *ret = m; m = NULL; @@ -453,14 +476,27 @@ Manager *manager_free(Manager *m) { sd_event_source_unref(m->dns_ipv4_event_source); sd_event_source_unref(m->dns_ipv6_event_source); - safe_close(m->dns_ipv4_fd); safe_close(m->dns_ipv6_fd); + sd_event_source_unref(m->llmnr_ipv4_udp_event_source); + sd_event_source_unref(m->llmnr_ipv6_udp_event_source); + safe_close(m->llmnr_ipv4_udp_fd); + safe_close(m->llmnr_ipv6_udp_fd); + + sd_event_source_unref(m->llmnr_ipv4_tcp_event_source); + sd_event_source_unref(m->llmnr_ipv6_tcp_event_source); + safe_close(m->llmnr_ipv4_tcp_fd); + safe_close(m->llmnr_ipv6_tcp_fd); + sd_event_source_unref(m->bus_retry_event_source); sd_bus_unref(m->bus); sd_event_unref(m->event); + + dns_resource_key_unref(m->host_ipv4_key); + dns_resource_key_unref(m->host_ipv6_key); + free(m->hostname); free(m); return NULL; @@ -475,7 +511,7 @@ static void write_resolve_conf_server(DnsServer *s, FILE *f, unsigned *count) { assert(count); r = in_addr_to_string(s->family, &s->address, &t); - if (r < 0) { + if (r < 0) { log_warning("Invalid DNS address. Ignoring."); return; } @@ -511,13 +547,9 @@ int manager_write_resolv_conf(Manager *m) { "# resolv.conf(5) in a different way, replace the symlink by a\n" "# static file or a different symlink.\n\n", f); - HASHMAP_FOREACH(l, m->links, i) { - LIST_FOREACH(servers, s, l->link_dns_servers) - write_resolve_conf_server(s, f, &count); - - LIST_FOREACH(servers, s, l->dhcp_dns_servers) + HASHMAP_FOREACH(l, m->links, i) + LIST_FOREACH(servers, s, l->dns_servers) write_resolve_conf_server(s, f, &count); - } LIST_FOREACH(servers, s, m->dns_servers) write_resolve_conf_server(s, f, &count); @@ -539,35 +571,44 @@ fail: return r; } -int manager_dns_ipv4_recv(Manager *m, DnsPacket **ret) { +int manager_recv(Manager *m, int fd, DnsProtocol protocol, DnsPacket **ret) { _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL; + union { + struct cmsghdr header; /* For alignment */ + uint8_t buffer[CMSG_SPACE(MAX(sizeof(struct in_pktinfo), sizeof(struct in6_pktinfo))) + + CMSG_SPACE(int) /* ttl/hoplimit */ + + EXTRA_CMSG_SPACE /* kernel appears to require extra buffer space */]; + } control; + union sockaddr_union sa; struct msghdr mh = {}; - int fd, ms = 0, r; + struct cmsghdr *cmsg; struct iovec iov; + int ms = 0, r; ssize_t l; assert(m); + assert(fd >= 0); assert(ret); - fd = manager_dns_ipv4_fd(m); - if (fd < 0) - return fd; - r = ioctl(fd, FIONREAD, &ms); if (r < 0) return -errno; if (ms < 0) return -EIO; - r = dns_packet_new(&p, ms); + r = dns_packet_new(&p, protocol, ms); if (r < 0) return r; iov.iov_base = DNS_PACKET_DATA(p); iov.iov_len = p->allocated; + mh.msg_name = &sa.sa; + mh.msg_namelen = sizeof(sa); mh.msg_iov = &iov; mh.msg_iovlen = 1; + mh.msg_control = &control; + mh.msg_controllen = sizeof(control); l = recvmsg(fd, &mh, 0); if (l < 0) { @@ -580,56 +621,78 @@ int manager_dns_ipv4_recv(Manager *m, DnsPacket **ret) { if (l <= 0) return -EIO; + assert(!(mh.msg_flags & MSG_CTRUNC)); + assert(!(mh.msg_flags & MSG_TRUNC)); + p->size = (size_t) l; - *ret = p; - p = NULL; + p->family = sa.sa.sa_family; + p->ipproto = IPPROTO_UDP; + if (p->family == AF_INET) { + p->sender.in = sa.in.sin_addr; + p->sender_port = be16toh(sa.in.sin_port); + } else if (p->family == AF_INET6) { + p->sender.in6 = sa.in6.sin6_addr; + p->sender_port = be16toh(sa.in6.sin6_port); + p->ifindex = sa.in6.sin6_scope_id; + } else + return -EAFNOSUPPORT; - return 1; -} + for (cmsg = CMSG_FIRSTHDR(&mh); cmsg; cmsg = CMSG_NXTHDR(&mh, cmsg)) { -int manager_dns_ipv6_recv(Manager *m, DnsPacket **ret) { - _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL; - struct msghdr mh = {}; - struct iovec iov; - int fd, ms = 0, r; - ssize_t l; + if (cmsg->cmsg_level == IPPROTO_IPV6) { + assert(p->family == AF_INET6); - assert(m); - assert(ret); + switch (cmsg->cmsg_type) { - fd = manager_dns_ipv6_fd(m); - if (fd < 0) - return fd; + case IPV6_PKTINFO: { + struct in6_pktinfo *i = (struct in6_pktinfo*) CMSG_DATA(cmsg); - r = ioctl(fd, FIONREAD, &ms); - if (r < 0) - return -errno; - if (ms < 0) - return -EIO; + if (p->ifindex <= 0) + p->ifindex = i->ipi6_ifindex; - r = dns_packet_new(&p, ms); - if (r < 0) - return r; + p->destination.in6 = i->ipi6_addr; + break; + } - iov.iov_base = DNS_PACKET_DATA(p); - iov.iov_len = p->allocated; + case IPV6_HOPLIMIT: + p->ttl = *(int *) CMSG_DATA(cmsg); + break; - mh.msg_iov = &iov; - mh.msg_iovlen = 1; + } + } else if (cmsg->cmsg_level == IPPROTO_IP) { + assert(p->family == AF_INET); - l = recvmsg(fd, &mh, 0); - if (l < 0) { - if (errno == EAGAIN || errno == EINTR) - return 0; + switch (cmsg->cmsg_type) { - return -errno; + case IP_PKTINFO: { + struct in_pktinfo *i = (struct in_pktinfo*) CMSG_DATA(cmsg); + + if (p->ifindex <= 0) + p->ifindex = i->ipi_ifindex; + + p->destination.in = i->ipi_addr; + break; + } + + case IP_TTL: + p->ttl = *(int *) CMSG_DATA(cmsg); + break; + } + } } - if (l <= 0) - return -EIO; + /* The Linux kernel sets the interface index to the loopback + * device if the packet came from the local host since it + * avoids the routing table in such a case. Let's unset the + * interface index in such a case. */ + if (p->ifindex > 0 && manager_ifindex_is_loopback(m, p->ifindex) != 0) + p->ifindex = 0; - p->size = (size_t) l; + /* If we don't know the interface index still, we look for the + * first local interface with a matching address. Yuck! */ + if (p->ifindex <= 0) + p->ifindex = manager_find_ifindex(m, p->family, &p->destination); *ret = p; p = NULL; @@ -637,43 +700,31 @@ int manager_dns_ipv6_recv(Manager *m, DnsPacket **ret) { return 1; } -static int on_dns_ipv4_packet(sd_event_source *s, int fd, uint32_t revents, void *userdata) { +static int on_dns_packet(sd_event_source *s, int fd, uint32_t revents, void *userdata) { _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL; DnsQueryTransaction *t = NULL; Manager *m = userdata; int r; - r = manager_dns_ipv4_recv(m, &p); + r = manager_recv(m, fd, DNS_PROTOCOL_DNS, &p); if (r <= 0) return r; - t = hashmap_get(m->dns_query_transactions, UINT_TO_PTR(DNS_PACKET_ID(p))); - if (!t) - return 0; - - dns_query_transaction_reply(t, p); - return 0; -} - -static int on_dns_ipv6_packet(sd_event_source *s, int fd, uint32_t revents, void *userdata) { - _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL; - DnsQueryTransaction *t = NULL; - Manager *m = userdata; - int r; + if (dns_packet_validate_reply(p) > 0) { + t = hashmap_get(m->dns_query_transactions, UINT_TO_PTR(DNS_PACKET_ID(p))); + if (!t) + return 0; - r = manager_dns_ipv6_recv(m, &p); - if (r <= 0) - return r; + dns_query_transaction_process_reply(t, p); - t = hashmap_get(m->dns_query_transactions, UINT_TO_PTR(DNS_PACKET_ID(p))); - if (!t) - return 0; + } else + log_debug("Invalid DNS packet."); - dns_query_transaction_reply(t, p); return 0; } int manager_dns_ipv4_fd(Manager *m) { + const int one = 1; int r; assert(m); @@ -685,14 +736,25 @@ int manager_dns_ipv4_fd(Manager *m) { if (m->dns_ipv4_fd < 0) return -errno; - r = sd_event_add_io(m->event, &m->dns_ipv4_event_source, m->dns_ipv4_fd, EPOLLIN, on_dns_ipv4_packet, m); + r = setsockopt(m->dns_ipv4_fd, IPPROTO_IP, IP_PKTINFO, &one, sizeof(one)); + if (r < 0) { + r = -errno; + goto fail; + } + + r = sd_event_add_io(m->event, &m->dns_ipv4_event_source, m->dns_ipv4_fd, EPOLLIN, on_dns_packet, m); if (r < 0) - return r; + goto fail; return m->dns_ipv4_fd; + +fail: + m->dns_ipv4_fd = safe_close(m->dns_ipv4_fd); + return r; } int manager_dns_ipv6_fd(Manager *m) { + const int one = 1; int r; assert(m); @@ -704,11 +766,21 @@ int manager_dns_ipv6_fd(Manager *m) { if (m->dns_ipv6_fd < 0) return -errno; - r = sd_event_add_io(m->event, &m->dns_ipv6_event_source, m->dns_ipv6_fd, EPOLLIN, on_dns_ipv6_packet, m); + r = setsockopt(m->dns_ipv6_fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &one, sizeof(one)); + if (r < 0) { + r = -errno; + goto fail; + } + + r = sd_event_add_io(m->event, &m->dns_ipv6_event_source, m->dns_ipv6_fd, EPOLLIN, on_dns_packet, m); if (r < 0) - return r; + goto fail; return m->dns_ipv6_fd; + +fail: + m->dns_ipv6_fd = safe_close(m->dns_ipv6_fd); + return r; } static int sendmsg_loop(int fd, struct msghdr *mh, int flags) { @@ -735,28 +807,28 @@ static int sendmsg_loop(int fd, struct msghdr *mh, int flags) { } } -int manager_dns_ipv4_send(Manager *m, DnsServer *srv, int ifindex, DnsPacket *p) { +static int manager_ipv4_send(Manager *m, int fd, int ifindex, const struct in_addr *addr, uint16_t port, DnsPacket *p) { union sockaddr_union sa = { .in.sin_family = AF_INET, - .in.sin_port = htobe16(53), }; + union { + struct cmsghdr header; /* For alignment */ + uint8_t buffer[CMSG_SPACE(sizeof(struct in_pktinfo))]; + } control; struct msghdr mh = {}; struct iovec iov; - uint8_t control[CMSG_SPACE(sizeof(struct in_pktinfo))]; - int fd; assert(m); - assert(srv); + assert(fd >= 0); + assert(addr); + assert(port > 0); assert(p); - fd = manager_dns_ipv4_fd(m); - if (fd < 0) - return fd; - iov.iov_base = DNS_PACKET_DATA(p); iov.iov_len = p->size; - sa.in.sin_addr = srv->address.in; + sa.in.sin_addr = *addr; + sa.in.sin_port = htobe16(port), mh.msg_iov = &iov; mh.msg_iovlen = 1; @@ -769,7 +841,7 @@ int manager_dns_ipv4_send(Manager *m, DnsServer *srv, int ifindex, DnsPacket *p) zero(control); - mh.msg_control = control; + mh.msg_control = &control; mh.msg_controllen = CMSG_LEN(sizeof(struct in_pktinfo)); cmsg = CMSG_FIRSTHDR(&mh); @@ -784,29 +856,28 @@ int manager_dns_ipv4_send(Manager *m, DnsServer *srv, int ifindex, DnsPacket *p) return sendmsg_loop(fd, &mh, 0); } -int manager_dns_ipv6_send(Manager *m, DnsServer *srv, int ifindex, DnsPacket *p) { +static int manager_ipv6_send(Manager *m, int fd, int ifindex, const struct in6_addr *addr, uint16_t port, DnsPacket *p) { union sockaddr_union sa = { .in6.sin6_family = AF_INET6, - .in6.sin6_port = htobe16(53), }; - + union { + struct cmsghdr header; /* For alignment */ + uint8_t buffer[CMSG_SPACE(sizeof(struct in6_pktinfo))]; + } control; struct msghdr mh = {}; struct iovec iov; - uint8_t control[CMSG_SPACE(sizeof(struct in6_pktinfo))]; - int fd; assert(m); - assert(srv); + assert(fd >= 0); + assert(addr); + assert(port > 0); assert(p); - fd = manager_dns_ipv6_fd(m); - if (fd < 0) - return fd; - iov.iov_base = DNS_PACKET_DATA(p); iov.iov_len = p->size; - sa.in6.sin6_addr = srv->address.in6; + sa.in6.sin6_addr = *addr; + sa.in6.sin6_port = htobe16(port), sa.in6.sin6_scope_id = ifindex; mh.msg_iov = &iov; @@ -820,7 +891,7 @@ int manager_dns_ipv6_send(Manager *m, DnsServer *srv, int ifindex, DnsPacket *p) zero(control); - mh.msg_control = control; + mh.msg_control = &control; mh.msg_controllen = CMSG_LEN(sizeof(struct in6_pktinfo)); cmsg = CMSG_FIRSTHDR(&mh); @@ -835,7 +906,24 @@ int manager_dns_ipv6_send(Manager *m, DnsServer *srv, int ifindex, DnsPacket *p) return sendmsg_loop(fd, &mh, 0); } -DnsServer* manager_find_dns_server(Manager *m, unsigned char family, union in_addr_union *in_addr) { +int manager_send(Manager *m, int fd, int ifindex, int family, const union in_addr_union *addr, uint16_t port, DnsPacket *p) { + assert(m); + assert(fd >= 0); + assert(addr); + assert(port > 0); + assert(p); + + log_debug("Sending %s packet with id %u on interface %i/%s", DNS_PACKET_QR(p) ? "response" : "query", DNS_PACKET_ID(p), ifindex, af_to_name(family)); + + if (family == AF_INET) + return manager_ipv4_send(m, fd, ifindex, &addr->in, port, p); + else if (family == AF_INET6) + return manager_ipv6_send(m, fd, ifindex, &addr->in6, port, p); + + return -EAFNOSUPPORT; +} + +DnsServer* manager_find_dns_server(Manager *m, int family, const union in_addr_union *in_addr) { DnsServer *s; assert(m); @@ -878,3 +966,444 @@ void manager_next_dns_server(Manager *m) { m->current_dns_server = m->dns_servers; } + +uint32_t manager_find_mtu(Manager *m) { + uint32_t mtu = 0; + Link *l; + Iterator i; + + /* If we don't know on which link a DNS packet would be + * delivered, let's find the largest MTU that works on all + * interfaces we know of */ + + HASHMAP_FOREACH(l, m->links, i) { + if (l->mtu <= 0) + continue; + + if (mtu <= 0 || l->mtu < mtu) + mtu = l->mtu; + } + + return mtu; +} + +static int on_llmnr_packet(sd_event_source *s, int fd, uint32_t revents, void *userdata) { + _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL; + DnsQueryTransaction *t = NULL; + Manager *m = userdata; + int r; + + r = manager_recv(m, fd, DNS_PROTOCOL_LLMNR, &p); + if (r <= 0) + return r; + + if (dns_packet_validate_reply(p) > 0) { + log_debug("Got reply packet for id %u", DNS_PACKET_ID(p)); + + t = hashmap_get(m->dns_query_transactions, UINT_TO_PTR(DNS_PACKET_ID(p))); + if (!t) + return 0; + + dns_query_transaction_process_reply(t, p); + + } else if (dns_packet_validate_query(p) > 0) { + Link *l; + + l = hashmap_get(m->links, INT_TO_PTR(p->ifindex)); + if (l) { + DnsScope *scope = NULL; + + if (p->family == AF_INET) + scope = l->llmnr_ipv4_scope; + else if (p->family == AF_INET6) + scope = l->llmnr_ipv6_scope; + + if (scope) + dns_scope_process_query(scope, NULL, p); + } + } else + log_debug("Invalid LLMNR packet."); + + return 0; +} + +int manager_llmnr_ipv4_udp_fd(Manager *m) { + union sockaddr_union sa = { + .in.sin_family = AF_INET, + .in.sin_port = htobe16(5355), + }; + static const int one = 1, pmtu = IP_PMTUDISC_DONT, ttl = 255; + int r; + + assert(m); + + if (m->llmnr_ipv4_udp_fd >= 0) + return m->llmnr_ipv4_udp_fd; + + m->llmnr_ipv4_udp_fd = socket(AF_INET, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0); + if (m->llmnr_ipv4_udp_fd < 0) + return -errno; + + /* RFC 4795, section 2.5 recommends setting the TTL of UDP packets to 255. */ + r = setsockopt(m->llmnr_ipv4_udp_fd, IPPROTO_IP, IP_TTL, &ttl, sizeof(ttl)); + if (r < 0) { + r = -errno; + goto fail; + } + + r = setsockopt(m->llmnr_ipv4_udp_fd, IPPROTO_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl)); + if (r < 0) { + r = -errno; + goto fail; + } + + r = setsockopt(m->llmnr_ipv4_udp_fd, IPPROTO_IP, IP_MULTICAST_LOOP, &one, sizeof(one)); + if (r < 0) { + r = -errno; + goto fail; + } + + r = setsockopt(m->llmnr_ipv4_udp_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)); + if (r < 0) { + r = -errno; + goto fail; + } + + r = setsockopt(m->llmnr_ipv4_udp_fd, IPPROTO_IP, IP_PKTINFO, &one, sizeof(one)); + if (r < 0) { + r = -errno; + goto fail; + } + + r = setsockopt(m->llmnr_ipv4_udp_fd, IPPROTO_IP, IP_RECVTTL, &one, sizeof(one)); + if (r < 0) { + r = -errno; + goto fail; + } + + /* Disable Don't-Fragment bit in the IP header */ + r = setsockopt(m->llmnr_ipv4_udp_fd, IPPROTO_IP, IP_MTU_DISCOVER, &pmtu, sizeof(pmtu)); + if (r < 0) { + r = -errno; + goto fail; + } + + r = bind(m->llmnr_ipv4_udp_fd, &sa.sa, sizeof(sa.in)); + if (r < 0) { + r = -errno; + goto fail; + } + + r = sd_event_add_io(m->event, &m->llmnr_ipv4_udp_event_source, m->llmnr_ipv4_udp_fd, EPOLLIN, on_llmnr_packet, m); + if (r < 0) + goto fail; + + return m->llmnr_ipv4_udp_fd; + +fail: + m->llmnr_ipv4_udp_fd = safe_close(m->llmnr_ipv4_udp_fd); + return r; +} + +int manager_llmnr_ipv6_udp_fd(Manager *m) { + union sockaddr_union sa = { + .in6.sin6_family = AF_INET6, + .in6.sin6_port = htobe16(5355), + }; + static const int one = 1, ttl = 255; + int r; + + assert(m); + + if (m->llmnr_ipv6_udp_fd >= 0) + return m->llmnr_ipv6_udp_fd; + + m->llmnr_ipv6_udp_fd = socket(AF_INET6, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0); + if (m->llmnr_ipv6_udp_fd < 0) + return -errno; + + r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_UNICAST_HOPS, &ttl, sizeof(ttl)); + if (r < 0) { + r = -errno; + goto fail; + } + + /* RFC 4795, section 2.5 recommends setting the TTL of UDP packets to 255. */ + r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &ttl, sizeof(ttl)); + if (r < 0) { + r = -errno; + goto fail; + } + + r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &one, sizeof(one)); + if (r < 0) { + r = -errno; + goto fail; + } + + r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_V6ONLY, &one, sizeof(one)); + if (r < 0) { + r = -errno; + goto fail; + } + + r = setsockopt(m->llmnr_ipv6_udp_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)); + if (r < 0) { + r = -errno; + goto fail; + } + + r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &one, sizeof(one)); + if (r < 0) { + r = -errno; + goto fail; + } + + r = setsockopt(m->llmnr_ipv6_udp_fd, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &one, sizeof(one)); + if (r < 0) { + r = -errno; + goto fail; + } + + r = bind(m->llmnr_ipv6_udp_fd, &sa.sa, sizeof(sa.in6)); + if (r < 0) { + r = -errno; + goto fail; + } + + r = sd_event_add_io(m->event, &m->llmnr_ipv6_udp_event_source, m->llmnr_ipv6_udp_fd, EPOLLIN, on_llmnr_packet, m); + if (r < 0) { + r = -errno; + goto fail; + } + + return m->llmnr_ipv6_udp_fd; + +fail: + m->llmnr_ipv6_udp_fd = safe_close(m->llmnr_ipv6_udp_fd); + return r; +} + +static int on_llmnr_stream_packet(DnsStream *s) { + assert(s); + + if (dns_packet_validate_query(s->read_packet) > 0) { + Link *l; + + l = hashmap_get(s->manager->links, INT_TO_PTR(s->read_packet->ifindex)); + if (l) { + DnsScope *scope = NULL; + + if (s->read_packet->family == AF_INET) + scope = l->llmnr_ipv4_scope; + else if (s->read_packet->family == AF_INET6) + scope = l->llmnr_ipv6_scope; + + if (scope) { + dns_scope_process_query(scope, s, s->read_packet); + + /* If no reply packet was set, we free the stream */ + if (s->write_packet) + return 0; + } + } + } + + dns_stream_free(s); + return 0; +} + +static int on_llmnr_stream(sd_event_source *s, int fd, uint32_t revents, void *userdata) { + DnsStream *stream; + Manager *m = userdata; + int cfd, r; + + cfd = accept4(fd, NULL, NULL, SOCK_NONBLOCK|SOCK_CLOEXEC); + if (cfd < 0) { + if (errno == EAGAIN || errno == EINTR) + return 0; + + return -errno; + } + + r = dns_stream_new(m, &stream, DNS_PROTOCOL_LLMNR, cfd); + if (r < 0) { + safe_close(cfd); + return r; + } + + stream->on_packet = on_llmnr_stream_packet; + return 0; +} + +int manager_llmnr_ipv4_tcp_fd(Manager *m) { + union sockaddr_union sa = { + .in.sin_family = AF_INET, + .in.sin_port = htobe16(5355), + }; + static const int one = 1, pmtu = IP_PMTUDISC_DONT; + int r; + + assert(m); + + if (m->llmnr_ipv4_tcp_fd >= 0) + return m->llmnr_ipv4_tcp_fd; + + m->llmnr_ipv4_tcp_fd = socket(AF_INET, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0); + if (m->llmnr_ipv4_tcp_fd < 0) + return -errno; + + /* RFC 4795, section 2.5. requires setting the TTL of TCP streams to 1 */ + r = setsockopt(m->llmnr_ipv4_tcp_fd, IPPROTO_IP, IP_TTL, &one, sizeof(one)); + if (r < 0) { + r = -errno; + goto fail; + } + + r = setsockopt(m->llmnr_ipv4_tcp_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)); + if (r < 0) { + r = -errno; + goto fail; + } + + r = setsockopt(m->llmnr_ipv4_tcp_fd, IPPROTO_IP, IP_PKTINFO, &one, sizeof(one)); + if (r < 0) { + r = -errno; + goto fail; + } + + r = setsockopt(m->llmnr_ipv4_tcp_fd, IPPROTO_IP, IP_RECVTTL, &one, sizeof(one)); + if (r < 0) { + r = -errno; + goto fail; + } + + /* Disable Don't-Fragment bit in the IP header */ + r = setsockopt(m->llmnr_ipv4_tcp_fd, IPPROTO_IP, IP_MTU_DISCOVER, &pmtu, sizeof(pmtu)); + if (r < 0) { + r = -errno; + goto fail; + } + + r = bind(m->llmnr_ipv4_tcp_fd, &sa.sa, sizeof(sa.in)); + if (r < 0) { + r = -errno; + goto fail; + } + + r = listen(m->llmnr_ipv4_tcp_fd, SOMAXCONN); + if (r < 0) { + r = -errno; + goto fail; + } + + r = sd_event_add_io(m->event, &m->llmnr_ipv4_tcp_event_source, m->llmnr_ipv4_tcp_fd, EPOLLIN, on_llmnr_stream, m); + if (r < 0) + goto fail; + + return m->llmnr_ipv4_tcp_fd; + +fail: + m->llmnr_ipv4_tcp_fd = safe_close(m->llmnr_ipv4_tcp_fd); + return r; +} + +int manager_llmnr_ipv6_tcp_fd(Manager *m) { + union sockaddr_union sa = { + .in6.sin6_family = AF_INET6, + .in6.sin6_port = htobe16(5355), + }; + static const int one = 1; + int r; + + assert(m); + + if (m->llmnr_ipv6_tcp_fd >= 0) + return m->llmnr_ipv6_tcp_fd; + + m->llmnr_ipv6_tcp_fd = socket(AF_INET6, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0); + if (m->llmnr_ipv6_tcp_fd < 0) + return -errno; + + /* RFC 4795, section 2.5. requires setting the TTL of TCP streams to 1 */ + r = setsockopt(m->llmnr_ipv6_tcp_fd, IPPROTO_IPV6, IPV6_UNICAST_HOPS, &one, sizeof(one)); + if (r < 0) { + r = -errno; + goto fail; + } + + r = setsockopt(m->llmnr_ipv6_tcp_fd, IPPROTO_IPV6, IPV6_V6ONLY, &one, sizeof(one)); + if (r < 0) { + r = -errno; + goto fail; + } + + r = setsockopt(m->llmnr_ipv6_tcp_fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)); + if (r < 0) { + r = -errno; + goto fail; + } + + r = setsockopt(m->llmnr_ipv6_tcp_fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &one, sizeof(one)); + if (r < 0) { + r = -errno; + goto fail; + } + + r = setsockopt(m->llmnr_ipv6_tcp_fd, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &one, sizeof(one)); + if (r < 0) { + r = -errno; + goto fail; + } + + r = bind(m->llmnr_ipv6_tcp_fd, &sa.sa, sizeof(sa.in6)); + if (r < 0) { + r = -errno; + goto fail; + } + + r = listen(m->llmnr_ipv6_tcp_fd, SOMAXCONN); + if (r < 0) { + r = -errno; + goto fail; + } + + r = sd_event_add_io(m->event, &m->llmnr_ipv6_tcp_event_source, m->llmnr_ipv6_tcp_fd, EPOLLIN, on_llmnr_stream, m); + if (r < 0) { + r = -errno; + goto fail; + } + + return m->llmnr_ipv6_tcp_fd; + +fail: + m->llmnr_ipv6_tcp_fd = safe_close(m->llmnr_ipv6_tcp_fd); + return r; +} + +int manager_ifindex_is_loopback(Manager *m, int ifindex) { + Link *l; + assert(m); + + if (ifindex <= 0) + return -EINVAL; + + l = hashmap_get(m->links, INT_TO_PTR(ifindex)); + if (l->flags & IFF_LOOPBACK) + return 1; + + return 0; +} + +int manager_find_ifindex(Manager *m, int family, const union in_addr_union *in_addr) { + Link *l; + Iterator i; + + assert(m); + + HASHMAP_FOREACH(l, m->links, i) + if (link_find_address(l, family, in_addr)) + return l->ifindex; + + return 0; +}