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=ae173991da2ca11cbb18102ea5fdd7650d3d690f;hb=0f05c387597a93fa74cdf7d351fd255aca56026d;hpb=091a364c802e34a58f3260c9cb5db9b75c62215c diff --git a/src/resolve/resolved-manager.c b/src/resolve/resolved-manager.c index ae173991d..319baf788 100644 --- a/src/resolve/resolved-manager.c +++ b/src/resolve/resolved-manager.c @@ -21,18 +21,289 @@ #include #include -#include +#include +#include +#include +#include -#include "resolved.h" +#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 "mkdir.h" +#include "socket-util.h" +#include "af-list.h" +#include "resolved.h" + +#define SEND_TIMEOUT_USEC (200 * USEC_PER_MSEC) + +static int manager_process_link(sd_rtnl *rtnl, sd_rtnl_message *mm, void *userdata) { + Manager *m = userdata; + uint16_t type; + Link *l; + int ifindex, r; + + assert(rtnl); + assert(m); + assert(mm); + + r = sd_rtnl_message_get_type(mm, &type); + if (r < 0) + goto fail; + + r = sd_rtnl_message_link_get_ifindex(mm, &ifindex); + if (r < 0) + goto fail; + + l = hashmap_get(m->links, INT_TO_PTR(ifindex)); + + switch (type) { + + case RTM_NEWLINK:{ + bool is_new = !l; + + if (!l) { + r = link_new(m, &l, ifindex); + if (r < 0) + goto fail; + } + + r = link_update_rtnl(l, mm); + 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/%s", l->ifindex, l->name); + link_free(l); + } + + break; + } + + return 0; + +fail: + log_warning("Failed to process RTNL link message: %s", strerror(-r)); + return 0; +} + +static int manager_process_address(sd_rtnl *rtnl, sd_rtnl_message *mm, void *userdata) { + Manager *m = userdata; + union in_addr_union address; + uint16_t type; + int r, ifindex, family; + LinkAddress *a; + Link *l; + + assert(rtnl); + assert(mm); + assert(m); + + r = sd_rtnl_message_get_type(mm, &type); + if (r < 0) + goto fail; + + r = sd_rtnl_message_addr_get_ifindex(mm, &ifindex); + if (r < 0) + goto fail; + + l = hashmap_get(m->links, INT_TO_PTR(ifindex)); + if (!l) + return 0; + + r = sd_rtnl_message_addr_get_family(mm, &family); + if (r < 0) + goto fail; + + switch (family) { + + case AF_INET: + r = sd_rtnl_message_read_in_addr(mm, IFA_LOCAL, &address.in); + if (r < 0) { + r = sd_rtnl_message_read_in_addr(mm, IFA_ADDRESS, &address.in); + if (r < 0) + goto fail; + } + + break; + + case AF_INET6: + r = sd_rtnl_message_read_in6_addr(mm, IFA_LOCAL, &address.in6); + if (r < 0) { + r = sd_rtnl_message_read_in6_addr(mm, IFA_ADDRESS, &address.in6); + if (r < 0) + goto fail; + } + + break; + + default: + return 0; + } + + a = link_find_address(l, family, &address); + + switch (type) { + + case RTM_NEWADDR: + + if (!a) { + r = link_address_new(l, &a, family, &address); + if (r < 0) + return r; + } + + r = link_address_update_rtnl(a, mm); + if (r < 0) + return r; + + break; + + case RTM_DELADDR: + if (a) + link_address_free(a); + break; + } + + return 0; + +fail: + log_warning("Failed to process RTNL address message: %s", strerror(-r)); + return 0; +} + + +static int manager_rtnl_listen(Manager *m) { + _cleanup_rtnl_message_unref_ sd_rtnl_message *req = NULL, *reply = NULL; + sd_rtnl_message *i; + int r; + + assert(m); + + /* First, subscibe to interfaces coming and going */ + r = sd_rtnl_open(&m->rtnl, 3, RTNLGRP_LINK, RTNLGRP_IPV4_IFADDR, RTNLGRP_IPV6_IFADDR); + if (r < 0) + return r; + + r = sd_rtnl_attach_event(m->rtnl, m->event, 0); + if (r < 0) + return r; + + r = sd_rtnl_add_match(m->rtnl, RTM_NEWLINK, manager_process_link, m); + if (r < 0) + return r; + + r = sd_rtnl_add_match(m->rtnl, RTM_DELLINK, manager_process_link, m); + if (r < 0) + return r; + + r = sd_rtnl_add_match(m->rtnl, RTM_NEWADDR, manager_process_address, m); + if (r < 0) + return r; + + r = sd_rtnl_add_match(m->rtnl, RTM_DELADDR, manager_process_address, m); + if (r < 0) + return r; + + /* Then, enumerate all links */ + r = sd_rtnl_message_new_link(m->rtnl, &req, RTM_GETLINK, 0); + if (r < 0) + return r; + + r = sd_rtnl_message_request_dump(req, true); + if (r < 0) + return r; + + r = sd_rtnl_call(m->rtnl, req, 0, &reply); + if (r < 0) + return r; + + for (i = reply; i; i = sd_rtnl_message_next(i)) { + r = manager_process_link(m->rtnl, i, m); + if (r < 0) + return r; + } + + req = sd_rtnl_message_unref(req); + reply = sd_rtnl_message_unref(reply); + + /* Finally, enumerate all addresses, too */ + r = sd_rtnl_message_new_addr(m->rtnl, &req, RTM_GETADDR, 0, AF_UNSPEC); + if (r < 0) + return r; + + r = sd_rtnl_message_request_dump(req, true); + if (r < 0) + return r; + + r = sd_rtnl_call(m->rtnl, req, 0, &reply); + if (r < 0) + return r; + + for (i = reply; i; i = sd_rtnl_message_next(i)) { + r = manager_process_address(m->rtnl, i, m); + if (r < 0) + return r; + } + + return r; +} + +static int on_network_event(sd_event_source *s, int fd, uint32_t revents, void *userdata) { + Manager *m = userdata; + Iterator i; + Link *l; + int r; + + assert(m); + + sd_network_monitor_flush(m->network_monitor); + + HASHMAP_FOREACH(l, m->links, i) { + r = link_update_monitor(l); + if (r < 0) + log_warning("Failed to update monitor information for %i: %s", l->ifindex, strerror(-r)); + } + + r = manager_write_resolv_conf(m); + if (r < 0) + log_warning("Could not update resolv.conf: %s", strerror(-r)); + + return 0; +} -static int set_fallback_dns(Manager *m, const char *string) { +static int manager_network_monitor_listen(Manager *m) { + int r, fd, events; + + assert(m); + + r = sd_network_monitor_new(&m->network_monitor, NULL); + if (r < 0) + return r; + + fd = sd_network_monitor_get_fd(m->network_monitor); + if (fd < 0) + return fd; + + events = sd_network_monitor_get_events(m->network_monitor); + if (events < 0) + return events; + + r = sd_event_add_io(m->event, &m->network_event_source, fd, events, &on_network_event, m); + if (r < 0) + return r; + + return 0; +} + +static int parse_dns_server_string(Manager *m, const char *string) { char *word, *state; size_t length; int r; @@ -41,27 +312,26 @@ static int set_fallback_dns(Manager *m, const char *string) { assert(string); FOREACH_WORD_QUOTED(word, length, string, state) { - _cleanup_free_ Address *address = NULL; - Address *tail; - _cleanup_free_ char *addrstr = NULL; - - address = new0(Address, 1); - if (!address) - return -ENOMEM; + char buffer[length+1]; + int family; + union in_addr_union addr; - addrstr = strndup(word, length); - if (!addrstr) - return -ENOMEM; + memcpy(buffer, word, length); + buffer[length] = 0; - r = net_parse_inaddr(addrstr, &address->family, &address->in_addr); + r = in_addr_from_string_auto(buffer, &family, &addr); if (r < 0) { - log_debug("Ignoring invalid DNS address '%s'", addrstr); + log_warning("Ignoring invalid DNS address '%s'", buffer); continue; } - LIST_FIND_TAIL(addresses, m->fallback_dns, tail); - LIST_INSERT_AFTER(addresses, m->fallback_dns, tail, address); - address = NULL; + /* filter out duplicates */ + if (manager_find_dns_server(m, family, &addr)) + continue; + + r = dns_server_new(m, NULL, NULL, family, &addr); + if (r < 0) + return r; } return 0; @@ -80,63 +350,63 @@ int config_parse_dnsv( void *userdata) { Manager *m = userdata; - Address *address; + int r; assert(filename); assert(lvalue); assert(rvalue); assert(m); - while ((address = m->fallback_dns)) { - LIST_REMOVE(addresses, m->fallback_dns, address); - free(address); + /* Empty assignment means clear the list */ + if (isempty(rvalue)) { + while (m->dns_servers) + dns_server_free(m->dns_servers); + + return 0; } - set_fallback_dns(m, rvalue); + r = parse_dns_server_string(m, rvalue); + if (r < 0) { + log_error("Failed to parse DNS server string"); + return r; + } return 0; } -static int manager_parse_config_file(Manager *m) { - static const char fn[] = "/etc/systemd/resolved.conf"; - _cleanup_fclose_ FILE *f = NULL; - int r; - +int manager_parse_config_file(Manager *m) { assert(m); - f = fopen(fn, "re"); - if (!f) { - if (errno == ENOENT) - return 0; - - log_warning("Failed to open configuration file %s: %m", fn); - return -errno; - } - - r = config_parse(NULL, fn, f, "Resolve\0", config_item_perf_lookup, - (void*) resolved_gperf_lookup, false, false, m); - if (r < 0) - log_warning("Failed to parse configuration file: %s", strerror(-r)); - - return r; + return config_parse(NULL, "/etc/systemd/resolved.conf", NULL, + "Resolve\0", + config_item_perf_lookup, resolved_gperf_lookup, + false, false, true, m); } int manager_new(Manager **ret) { - _cleanup_manager_free_ Manager *m = NULL; + _cleanup_(manager_freep) Manager *m = NULL; int r; + assert(ret); + m = new0(Manager, 1); if (!m) return -ENOMEM; - r = set_fallback_dns(m, DNS_SERVERS); - if (r < 0) - return r; + 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 = manager_parse_config_file(m); + 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; @@ -146,62 +416,126 @@ int manager_new(Manager **ret) { sd_event_set_watchdog(m->event, true); + r = dns_scope_new(m, &m->unicast_scope, NULL, DNS_PROTOCOL_DNS, AF_UNSPEC); + if (r < 0) + return r; + + r = manager_network_monitor_listen(m); + if (r < 0) + return r; + + r = manager_rtnl_listen(m); + if (r < 0) + return r; + + r = manager_connect_bus(m); + 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; return 0; } -void manager_free(Manager *m) { - Address *address; +Manager *manager_free(Manager *m) { + Link *l; if (!m) - return; + return NULL; - sd_event_unref(m->event); + while (m->dns_queries) + dns_query_free(m->dns_queries); - while ((address = m->fallback_dns)) { - LIST_REMOVE(addresses, m->fallback_dns, address); - free(address); - } + hashmap_free(m->dns_query_transactions); + + while ((l = hashmap_first(m->links))) + link_free(l); + hashmap_free(m->links); + + dns_scope_free(m->unicast_scope); + + while (m->dns_servers) + dns_server_free(m->dns_servers); + + sd_event_source_unref(m->network_event_source); + sd_network_monitor_unref(m->network_monitor); + + 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; } -static void append_dns(FILE *f, void *dns, unsigned char family, unsigned *count) { - char buf[INET6_ADDRSTRLEN]; - const char *address; +static void write_resolve_conf_server(DnsServer *s, FILE *f, unsigned *count) { + _cleanup_free_ char *t = NULL; + int r; + assert(s); assert(f); - assert(dns); assert(count); - address = inet_ntop(family, dns, buf, INET6_ADDRSTRLEN); - if (!address) { + r = in_addr_to_string(s->family, &s->address, &t); + if (r < 0) { log_warning("Invalid DNS address. Ignoring."); return; } if (*count == MAXNS) - fputs("# Too many DNS servers configured, the following entries " - "may be ignored\n", f); - - fprintf(f, "nameserver %s\n", address); + fputs("# Too many DNS servers configured, the following entries may be ignored\n", f); + fprintf(f, "nameserver %s\n", t); (*count) ++; } -int manager_update_resolv_conf(Manager *m) { +int manager_write_resolv_conf(Manager *m) { + const char *path = "/run/systemd/resolve/resolv.conf"; _cleanup_free_ char *temp_path = NULL; _cleanup_fclose_ FILE *f = NULL; - _cleanup_free_ unsigned *indices = NULL; - Address *address; unsigned count = 0; - int n, r, i; + DnsServer *s; + Iterator i; + Link *l; + int r; assert(m); - r = fopen_temporary("/run/systemd/network/resolv.conf", &f, &temp_path); + r = fopen_temporary(path, &f, &temp_path); if (r < 0) return r; @@ -213,108 +547,863 @@ int manager_update_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); - n = sd_network_get_ifindices(&indices); - if (n < 0) - n = 0; - - for (i = 0; i < n; i++) { - _cleanup_dhcp_lease_unref_ sd_dhcp_lease *lease = NULL; - struct in_addr *nameservers; - struct in6_addr *nameservers6; - size_t nameservers_size; - - r = sd_network_dhcp_use_dns(indices[i]); - if (r > 0) { - r = sd_network_get_dhcp_lease(indices[i], &lease); - if (r >= 0) { - r = sd_dhcp_lease_get_dns(lease, &nameservers, &nameservers_size); - if (r >= 0) { - unsigned j; - - for (j = 0; j < nameservers_size; j++) - append_dns(f, &nameservers[j], AF_INET, &count); - } - } - } + HASHMAP_FOREACH(l, m->links, i) + LIST_FOREACH(servers, s, l->dns_servers) + write_resolve_conf_server(s, f, &count); - r = sd_network_get_dns(indices[i], &nameservers, &nameservers_size); - if (r >= 0) { - unsigned j; + LIST_FOREACH(servers, s, m->dns_servers) + write_resolve_conf_server(s, f, &count); - for (j = 0; j < nameservers_size; j++) - append_dns(f, &nameservers[j], AF_INET, &count); + r = fflush_and_check(f); + if (r < 0) + goto fail; - free(nameservers); - } + if (rename(temp_path, path) < 0) { + r = -errno; + goto fail; + } - r = sd_network_get_dns6(indices[i], &nameservers6, &nameservers_size); - if (r >= 0) { - unsigned j; + return 0; - for (j = 0; j < nameservers_size; j++) - append_dns(f, &nameservers6[j], AF_INET6, &count); +fail: + unlink(path); + unlink(temp_path); + return r; +} - free(nameservers6); - } - } +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 = {}; + struct cmsghdr *cmsg; + struct iovec iov; + int ms = 0, r; + ssize_t l; - LIST_FOREACH(addresses, address, m->fallback_dns) - append_dns(f, &address->in_addr, address->family, &count); + assert(m); + assert(fd >= 0); + assert(ret); - fflush(f); + r = ioctl(fd, FIONREAD, &ms); + if (r < 0) + return -errno; + if (ms < 0) + return -EIO; - if (ferror(f) || rename(temp_path, "/run/systemd/network/resolv.conf") < 0) { - r = -errno; - unlink("/run/systemd/network/resolv.conf"); - unlink(temp_path); + 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) { + if (errno == EAGAIN || errno == EINTR) + return 0; + + return -errno; } - return 0; -} + if (l <= 0) + return -EIO; -static int manager_network_event_handler(sd_event_source *s, int fd, uint32_t revents, - void *userdata) { - Manager *m = userdata; - int r; + assert(!(mh.msg_flags & MSG_CTRUNC)); + assert(!(mh.msg_flags & MSG_TRUNC)); - assert(m); + p->size = (size_t) l; - r = manager_update_resolv_conf(m); - if (r < 0) - log_warning("Could not update resolv.conf: %s", strerror(-r)); + 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; - sd_network_monitor_flush(m->network_monitor); + for (cmsg = CMSG_FIRSTHDR(&mh); cmsg; cmsg = CMSG_NXTHDR(&mh, cmsg)) { - return 0; -} + if (cmsg->cmsg_level == IPPROTO_IPV6) { + assert(p->family == AF_INET6); -int manager_network_monitor_listen(Manager *m) { - _cleanup_event_source_unref_ sd_event_source *event_source = NULL; - _cleanup_network_monitor_unref_ sd_network_monitor *monitor = NULL; - int r, fd, events; + switch (cmsg->cmsg_type) { - r = sd_network_monitor_new(NULL, &monitor); - if (r < 0) - return r; + case IPV6_PKTINFO: { + struct in6_pktinfo *i = (struct in6_pktinfo*) CMSG_DATA(cmsg); - fd = sd_network_monitor_get_fd(monitor); - if (fd < 0) - return fd; + if (p->ifindex <= 0) + p->ifindex = i->ipi6_ifindex; - events = sd_network_monitor_get_events(monitor); - if (events < 0) - return events; + p->destination.in6 = i->ipi6_addr; + break; + } - r = sd_event_add_io(m->event, &event_source, fd, events, - &manager_network_event_handler, m); - if (r < 0) - return r; + case IPV6_HOPLIMIT: + p->ttl = *(int *) CMSG_DATA(cmsg); + break; + + } + } else if (cmsg->cmsg_level == IPPROTO_IP) { + assert(p->family == AF_INET); + + switch (cmsg->cmsg_type) { + + 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; + } + } + } + + /* 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; + + /* 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; + + return 1; +} + +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_recv(m, fd, DNS_PROTOCOL_DNS, &p); + if (r <= 0) + return 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; + + dns_query_transaction_process_reply(t, p); + + } else + log_debug("Invalid DNS packet."); + + return 0; +} + +int manager_dns_ipv4_fd(Manager *m) { + const int one = 1; + int r; + + assert(m); + + if (m->dns_ipv4_fd >= 0) + return m->dns_ipv4_fd; + + m->dns_ipv4_fd = socket(AF_INET, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0); + if (m->dns_ipv4_fd < 0) + return -errno; + + 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) + 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); + + if (m->dns_ipv6_fd >= 0) + return m->dns_ipv6_fd; + + m->dns_ipv6_fd = socket(AF_INET6, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0); + if (m->dns_ipv6_fd < 0) + return -errno; + + 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) + 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) { + int r; + + assert(fd >= 0); + assert(mh); + + for (;;) { + if (sendmsg(fd, mh, flags) >= 0) + return 0; + + if (errno == EINTR) + continue; + + if (errno != EAGAIN) + return -errno; + + r = fd_wait_for_event(fd, POLLOUT, SEND_TIMEOUT_USEC); + if (r < 0) + return r; + if (r == 0) + return -ETIMEDOUT; + } +} + +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, + }; + union { + struct cmsghdr header; /* For alignment */ + uint8_t buffer[CMSG_SPACE(sizeof(struct in_pktinfo))]; + } control; + struct msghdr mh = {}; + struct iovec iov; + + assert(m); + assert(fd >= 0); + assert(addr); + assert(port > 0); + assert(p); + + iov.iov_base = DNS_PACKET_DATA(p); + iov.iov_len = p->size; + + sa.in.sin_addr = *addr; + sa.in.sin_port = htobe16(port), + + mh.msg_iov = &iov; + mh.msg_iovlen = 1; + mh.msg_name = &sa.sa; + mh.msg_namelen = sizeof(sa.in); + + if (ifindex > 0) { + struct cmsghdr *cmsg; + struct in_pktinfo *pi; + + zero(control); + + mh.msg_control = &control; + mh.msg_controllen = CMSG_LEN(sizeof(struct in_pktinfo)); + + cmsg = CMSG_FIRSTHDR(&mh); + cmsg->cmsg_len = mh.msg_controllen; + cmsg->cmsg_level = IPPROTO_IP; + cmsg->cmsg_type = IP_PKTINFO; + + pi = (struct in_pktinfo*) CMSG_DATA(cmsg); + pi->ipi_ifindex = ifindex; + } + + return sendmsg_loop(fd, &mh, 0); +} + +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, + }; + union { + struct cmsghdr header; /* For alignment */ + uint8_t buffer[CMSG_SPACE(sizeof(struct in6_pktinfo))]; + } control; + struct msghdr mh = {}; + struct iovec iov; + + assert(m); + assert(fd >= 0); + assert(addr); + assert(port > 0); + assert(p); + + iov.iov_base = DNS_PACKET_DATA(p); + iov.iov_len = p->size; + + sa.in6.sin6_addr = *addr; + sa.in6.sin6_port = htobe16(port), + sa.in6.sin6_scope_id = ifindex; + + mh.msg_iov = &iov; + mh.msg_iovlen = 1; + mh.msg_name = &sa.sa; + mh.msg_namelen = sizeof(sa.in6); + + if (ifindex > 0) { + struct cmsghdr *cmsg; + struct in6_pktinfo *pi; + + zero(control); + + mh.msg_control = &control; + mh.msg_controllen = CMSG_LEN(sizeof(struct in6_pktinfo)); + + cmsg = CMSG_FIRSTHDR(&mh); + cmsg->cmsg_len = mh.msg_controllen; + cmsg->cmsg_level = IPPROTO_IPV6; + cmsg->cmsg_type = IPV6_PKTINFO; + + pi = (struct in6_pktinfo*) CMSG_DATA(cmsg); + pi->ipi6_ifindex = ifindex; + } + + return sendmsg_loop(fd, &mh, 0); +} + +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); + assert(in_addr); + + LIST_FOREACH(servers, s, m->dns_servers) { + + if (s->family == family && + in_addr_equal(family, &s->address, in_addr)) + return s; + } + + return NULL; +} + +DnsServer *manager_get_dns_server(Manager *m) { + assert(m); + + if (!m->current_dns_server) + m->current_dns_server = m->dns_servers; + + return m->current_dns_server; +} + +void manager_next_dns_server(Manager *m) { + assert(m); + + if (!m->current_dns_server) { + m->current_dns_server = m->dns_servers; + return; + } + + if (!m->current_dns_server) + return; + + if (m->current_dns_server->servers_next) { + m->current_dns_server = m->current_dns_server->servers_next; + return; + } + + 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); - m->network_monitor = monitor; - m->network_event_source = event_source; - monitor = NULL; - event_source = NULL; + HASHMAP_FOREACH(l, m->links, i) + if (link_find_address(l, family, in_addr)) + return l->ifindex; return 0; }