Edit
IABSD.fr/src/sbin/dhcpleased/dhcpleased.c
dgl
- sbin/dhcpleased/dhcpleased.c
-
/* $OpenBSD: dhcpleased.c,v 1.43 2026/05/14 06:04:08 dgl Exp $ */ /* * Copyright (c) 2017, 2021 Florian Obser <florian@openbsd.org> * Copyright (c) 2005 Claudio Jeker <claudio@openbsd.org> * Copyright (c) 2004 Esben Norby <norby@openbsd.org> * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org> * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ #include <sys/types.h> #include <sys/ioctl.h> #include <sys/queue.h> #include <sys/socket.h> #include <sys/stat.h> #include <sys/syslog.h> #include <sys/sysctl.h> #include <sys/uio.h> #include <sys/wait.h> #include <net/if.h> #include <net/route.h> #include <net/if_dl.h> #include <netinet/in.h> #include <netinet/if_ether.h> #include <netinet/in_var.h> #include <arpa/inet.h> #include <err.h> #include <errno.h> #include <fcntl.h> #include <event.h> #include <ifaddrs.h> #include <imsg.h> #include <netdb.h> #include <pwd.h> #include <stddef.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <signal.h> #include <unistd.h> #include "bpf.h" #include "log.h" #include "dhcpleased.h" #include "frontend.h" #include "engine.h" #include "control.h" enum dhcpleased_process { PROC_MAIN, PROC_ENGINE, PROC_FRONTEND }; __dead void usage(void); __dead void main_shutdown(void); void main_sig_handler(int, short, void *); static pid_t start_child(enum dhcpleased_process, char *, int, int, int); void main_dispatch_frontend(int, short, void *); void main_dispatch_engine(int, short, void *); void open_bpfsock(uint32_t); void configure_interface(struct imsg_configure_interface *); void deconfigure_interface(struct imsg_configure_interface *); void propose_rdns(struct imsg_propose_rdns *); void configure_routes(uint8_t, struct imsg_configure_interface *); void configure_route(uint8_t, uint32_t, int, struct sockaddr_in *, struct sockaddr_in *, struct sockaddr_in *, struct sockaddr_in *, int); void read_lease_file(struct imsg_ifinfo *); static int main_imsg_send_ipc_sockets(struct imsgbuf *, struct imsgbuf *); int main_imsg_compose_frontend(int, int, void *, uint16_t); int main_imsg_compose_engine(int, int, void *, uint16_t); #ifndef SMALL int main_imsg_send_config(struct dhcpleased_conf *); #endif /* SMALL */ int main_reload(void); static struct imsgev *iev_frontend; static struct imsgev *iev_engine; #ifndef SMALL struct dhcpleased_conf *main_conf; #endif const char default_conffile[] = _PATH_CONF_FILE; const char *conffile = default_conffile; pid_t frontend_pid; pid_t engine_pid; int routesock, ioctl_sock, rtm_seq, no_lease_files; void main_sig_handler(int sig, short event, void *arg) { /* * Normal signal handler rules don't apply because libevent * decouples for us. */ switch (sig) { case SIGTERM: case SIGINT: main_shutdown(); case SIGHUP: #ifndef SMALL if (main_reload() == -1) log_warnx("configuration reload failed"); else log_debug("configuration reloaded"); #endif /* SMALL */ break; default: fatalx("unexpected signal"); } } __dead void usage(void) { extern char *__progname; fprintf(stderr, "usage: %s [-dnv] [-f file] [-s socket]\n", __progname); exit(1); } int main(int argc, char *argv[]) { struct event ev_sigint, ev_sigterm, ev_sighup; int ch; int debug = 0, engine_flag = 0, frontend_flag = 0; int verbose = 0, no_action = 0; char *saved_argv0; int pipe_main2frontend[2]; int pipe_main2engine[2]; int frontend_routesock, rtfilter, lockfd; int rtable_any = RTABLE_ANY; char *csock = _PATH_DHCPLEASED_SOCKET; #ifndef SMALL int control_fd; #endif /* SMALL */ log_init(1, LOG_DAEMON); /* Log to stderr until daemonized. */ log_setverbose(1); saved_argv0 = argv[0]; if (saved_argv0 == NULL) saved_argv0 = "dhcpleased"; while ((ch = getopt(argc, argv, "dEFf:ns:v")) != -1) { switch (ch) { case 'd': debug = 1; break; case 'E': engine_flag = 1; break; case 'F': frontend_flag = 1; break; case 'f': conffile = optarg; break; case 'n': no_action = 1; break; case 's': csock = optarg; break; case 'v': verbose++; break; default: usage(); } } argc -= optind; argv += optind; if (argc > 0 || (engine_flag && frontend_flag)) usage(); if (engine_flag) engine(debug, verbose); else if (frontend_flag) frontend(debug, verbose); #ifndef SMALL /* parse config file */ if ((main_conf = parse_config(conffile)) == NULL) exit(1); if (no_action) { if (verbose) print_config(main_conf); else fprintf(stderr, "configuration OK\n"); exit(0); } #endif /* SMALL */ /* Check for root privileges. */ if (geteuid()) errx(1, "need root privileges"); lockfd = open(_PATH_LOCKFILE, O_CREAT|O_RDWR|O_EXLOCK|O_NONBLOCK, 0600); if (lockfd == -1) { if (errno == EAGAIN) errx(1, "already running"); err(1, "%s", _PATH_LOCKFILE); } /* Check for assigned daemon user */ if (getpwnam(DHCPLEASED_USER) == NULL) errx(1, "unknown user %s", DHCPLEASED_USER); log_init(debug, LOG_DAEMON); log_setverbose(verbose); if (!debug) daemon(0, 0); if (socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC | SOCK_NONBLOCK, PF_UNSPEC, pipe_main2frontend) == -1) fatal("main2frontend socketpair"); if (socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC | SOCK_NONBLOCK, PF_UNSPEC, pipe_main2engine) == -1) fatal("main2engine socketpair"); /* Start children. */ engine_pid = start_child(PROC_ENGINE, saved_argv0, pipe_main2engine[1], debug, verbose); frontend_pid = start_child(PROC_FRONTEND, saved_argv0, pipe_main2frontend[1], debug, verbose); log_procinit("main"); if ((routesock = socket(AF_ROUTE, SOCK_RAW | SOCK_CLOEXEC | SOCK_NONBLOCK, AF_INET)) == -1) fatal("route socket"); shutdown(routesock, SHUT_RD); event_init(); /* Setup signal handler. */ signal_set(&ev_sigint, SIGINT, main_sig_handler, NULL); signal_set(&ev_sigterm, SIGTERM, main_sig_handler, NULL); signal_set(&ev_sighup, SIGHUP, main_sig_handler, NULL); signal_add(&ev_sigint, NULL); signal_add(&ev_sigterm, NULL); signal_add(&ev_sighup, NULL); signal(SIGPIPE, SIG_IGN); /* Setup pipes to children. */ if ((iev_frontend = malloc(sizeof(struct imsgev))) == NULL || (iev_engine = malloc(sizeof(struct imsgev))) == NULL) fatal(NULL); if (imsgbuf_init(&iev_frontend->ibuf, pipe_main2frontend[0]) == -1) fatal(NULL); imsgbuf_allow_fdpass(&iev_frontend->ibuf); iev_frontend->handler = main_dispatch_frontend; if (imsgbuf_init(&iev_engine->ibuf, pipe_main2engine[0]) == -1) fatal(NULL); imsgbuf_allow_fdpass(&iev_engine->ibuf); iev_engine->handler = main_dispatch_engine; /* Setup event handlers for pipes to engine & frontend. */ iev_frontend->events = EV_READ; event_set(&iev_frontend->ev, iev_frontend->ibuf.fd, iev_frontend->events, iev_frontend->handler, iev_frontend); event_add(&iev_frontend->ev, NULL); iev_engine->events = EV_READ; event_set(&iev_engine->ev, iev_engine->ibuf.fd, iev_engine->events, iev_engine->handler, iev_engine); event_add(&iev_engine->ev, NULL); if (main_imsg_send_ipc_sockets(&iev_frontend->ibuf, &iev_engine->ibuf)) fatal("could not establish imsg links"); if ((ioctl_sock = socket(AF_INET, SOCK_DGRAM | SOCK_CLOEXEC, 0)) == -1) fatal("socket"); if ((frontend_routesock = socket(AF_ROUTE, SOCK_RAW | SOCK_CLOEXEC, AF_INET)) == -1) fatal("route socket"); rtfilter = ROUTE_FILTER(RTM_IFINFO) | ROUTE_FILTER(RTM_PROPOSAL) | ROUTE_FILTER(RTM_IFANNOUNCE); if (setsockopt(frontend_routesock, AF_ROUTE, ROUTE_MSGFILTER, &rtfilter, sizeof(rtfilter)) == -1) fatal("setsockopt(ROUTE_MSGFILTER)"); if (setsockopt(frontend_routesock, AF_ROUTE, ROUTE_TABLEFILTER, &rtable_any, sizeof(rtable_any)) == -1) fatal("setsockopt(ROUTE_TABLEFILTER)"); #ifndef SMALL if ((control_fd = control_init(csock)) == -1) warnx("control socket setup failed"); #endif /* SMALL */ if (unveil(conffile, "r") == -1) fatal("unveil %s", conffile); if (unveil("/dev/bpf", "rw") == -1) fatal("unveil /dev/bpf"); if (unveil(_PATH_LEASE, "rwc") == -1) { no_lease_files = 1; log_warn("disabling lease files, unveil " _PATH_LEASE); } if (unveil(NULL, NULL) == -1) fatal("unveil"); #if notyet if (pledge("stdio inet rpath wpath sendfd wroute bpf", NULL) == -1) fatal("pledge"); #endif main_imsg_compose_frontend(IMSG_ROUTESOCK, frontend_routesock, NULL, 0); #ifndef SMALL if (control_fd != -1) main_imsg_compose_frontend(IMSG_CONTROLFD, control_fd, NULL, 0); main_imsg_send_config(main_conf); #endif /* SMALL */ main_imsg_compose_frontend(IMSG_STARTUP, -1, NULL, 0); event_dispatch(); main_shutdown(); return (0); } __dead void main_shutdown(void) { pid_t pid; int status; /* Close pipes. */ imsgbuf_clear(&iev_frontend->ibuf); close(iev_frontend->ibuf.fd); imsgbuf_clear(&iev_engine->ibuf); close(iev_engine->ibuf.fd); #ifndef SMALL config_clear(main_conf); #endif /* SMALL */ log_debug("waiting for children to terminate"); do { pid = wait(&status); if (pid == -1) { if (errno != EINTR && errno != ECHILD) fatal("wait"); } else if (WIFSIGNALED(status)) log_warnx("%s terminated; signal %d", (pid == engine_pid) ? "engine" : "frontend", WTERMSIG(status)); } while (pid != -1 || (pid == -1 && errno == EINTR)); free(iev_frontend); free(iev_engine); log_info("terminating"); exit(0); } static pid_t start_child(enum dhcpleased_process p, char *argv0, int fd, int debug, int verbose) { char *argv[7]; int argc = 0; pid_t pid; switch (pid = fork()) { case -1: fatal("cannot fork"); case 0: break; default: close(fd); return (pid); } if (fd != 3) { if (dup2(fd, 3) == -1) fatal("cannot setup imsg fd"); } else if (fcntl(fd, F_SETFD, 0) == -1) fatal("cannot setup imsg fd"); argv[argc++] = argv0; switch (p) { case PROC_MAIN: fatalx("Can not start main process"); case PROC_ENGINE: argv[argc++] = "-E"; break; case PROC_FRONTEND: argv[argc++] = "-F"; break; } if (debug) argv[argc++] = "-d"; if (verbose) argv[argc++] = "-v"; if (verbose > 1) argv[argc++] = "-v"; argv[argc++] = NULL; execvp(argv0, argv); fatal("execvp"); } void main_dispatch_frontend(int fd, short event, void *bula) { struct imsgev *iev = bula; struct imsgbuf *ibuf; struct imsg imsg; struct imsg_ifinfo imsg_ifinfo; ssize_t n; int shut = 0; uint32_t if_index, type; #ifndef SMALL int verbose; #endif /* SMALL */ ibuf = &iev->ibuf; if (event & EV_READ) { if ((n = imsgbuf_read(ibuf)) == -1) fatal("imsgbuf_read error"); if (n == 0) /* Connection closed. */ shut = 1; } if (event & EV_WRITE) { if (imsgbuf_write(ibuf) == -1) { if (errno == EPIPE) /* Connection closed. */ shut = 1; else fatal("imsgbuf_write"); } } for (;;) { if ((n = imsg_get(ibuf, &imsg)) == -1) fatal("imsg_get"); if (n == 0) /* No more messages. */ break; type = imsg_get_type(&imsg); switch (type) { case IMSG_OPEN_BPFSOCK: if (imsg_get_data(&imsg, &if_index, sizeof(if_index)) == -1) fatalx("%s: invalid %s", __func__, i2s(type)); open_bpfsock(if_index); break; #ifndef SMALL case IMSG_CTL_RELOAD: if (main_reload() == -1) log_warnx("configuration reload failed"); else log_warnx("configuration reloaded"); break; case IMSG_CTL_LOG_VERBOSE: if (imsg_get_data(&imsg, &verbose, sizeof(verbose)) == -1) fatalx("%s: invalid %s", __func__, i2s(type)); log_setverbose(verbose); break; #endif /* SMALL */ case IMSG_UPDATE_IF: if (imsg_get_data(&imsg, &imsg_ifinfo, sizeof(imsg_ifinfo)) == -1) fatalx("%s: invalid %s", __func__, i2s(type)); read_lease_file(&imsg_ifinfo); main_imsg_compose_engine(IMSG_UPDATE_IF, -1, &imsg_ifinfo, sizeof(imsg_ifinfo)); break; default: log_debug("%s: error handling imsg %d", __func__, type); break; } imsg_free(&imsg); } if (!shut) imsg_event_add(iev); else { /* This pipe is dead. Remove its event handler */ event_del(&iev->ev); event_loopexit(NULL); } } void main_dispatch_engine(int fd, short event, void *bula) { struct imsgev *iev = bula; struct imsgbuf *ibuf; struct imsg imsg; ssize_t n; uint32_t type; int shut = 0; ibuf = &iev->ibuf; if (event & EV_READ) { if ((n = imsgbuf_read(ibuf)) == -1) fatal("imsgbuf_read error"); if (n == 0) /* Connection closed. */ shut = 1; } if (event & EV_WRITE) { if (imsgbuf_write(ibuf) == -1) { if (errno == EPIPE) /* Connection closed. */ shut = 1; else fatal("imsgbuf_write"); } } for (;;) { if ((n = imsg_get(ibuf, &imsg)) == -1) fatal("imsg_get"); if (n == 0) /* No more messages. */ break; type = imsg_get_type(&imsg); switch (type) { case IMSG_CONFIGURE_INTERFACE: { struct imsg_configure_interface imsg_interface; if (imsg_get_data(&imsg, &imsg_interface, sizeof(imsg_interface)) == -1) fatalx("%s: invalid %s", __func__, i2s(type)); if (imsg_interface.file[ sizeof(imsg_interface.file) - 1] != '\0') fatalx("%s: invalid %s", __func__, i2s(type)); if (imsg_interface.domainname[ sizeof(imsg_interface.domainname) - 1] != '\0') fatalx("%s: invalid %s", __func__, i2s(type)); if (imsg_interface.hostname[ sizeof(imsg_interface.hostname) - 1] != '\0') fatalx("%s: invalid %s", __func__, i2s(type)); if (imsg_interface.routes_len >= MAX_DHCP_ROUTES) fatalx("%s: too many routes in imsg", __func__); configure_interface(&imsg_interface); break; } case IMSG_DECONFIGURE_INTERFACE: { struct imsg_configure_interface imsg_interface; if (imsg_get_data(&imsg, &imsg_interface, sizeof(imsg_interface)) == -1) fatalx("%s: invalid %s", __func__, i2s(type)); if (imsg_interface.file[ sizeof(imsg_interface.file) - 1] != '\0') fatalx("%s: invalid %s", __func__, i2s(type)); if (imsg_interface.domainname[ sizeof(imsg_interface.domainname) - 1] != '\0') fatalx("%s: invalid %s", __func__, i2s(type)); if (imsg_interface.hostname[ sizeof(imsg_interface.hostname) - 1] != '\0') fatalx("%s: invalid %s", __func__, i2s(type)); if (imsg_interface.routes_len >= MAX_DHCP_ROUTES) fatalx("%s: too many routes in imsg", __func__); deconfigure_interface(&imsg_interface); main_imsg_compose_frontend(IMSG_CLOSE_UDPSOCK, -1, &imsg_interface.if_index, sizeof(imsg_interface.if_index)); break; } case IMSG_WITHDRAW_ROUTES: { struct imsg_configure_interface imsg_interface; if (imsg_get_data(&imsg, &imsg_interface, sizeof(imsg_interface)) == -1) fatalx("%s: invalid %s", __func__, i2s(type)); if (imsg_interface.file[ sizeof(imsg_interface.file) - 1] != '\0') fatalx("%s: invalid %s", __func__, i2s(type)); if (imsg_interface.domainname[ sizeof(imsg_interface.domainname) - 1] != '\0') fatalx("%s: invalid %s", __func__, i2s(type)); if (imsg_interface.hostname[ sizeof(imsg_interface.hostname) - 1] != '\0') fatalx("%s: invalid %s", __func__, i2s(type)); if (imsg_interface.routes_len >= MAX_DHCP_ROUTES) fatalx("%s: too many routes in imsg", __func__); if (imsg_interface.routes_len > 0) configure_routes(RTM_DELETE, &imsg_interface); break; } case IMSG_PROPOSE_RDNS: { struct imsg_propose_rdns rdns; if (imsg_get_data(&imsg, &rdns, sizeof(rdns)) == -1) fatalx("%s: invalid %s", __func__, i2s(type)); if ((2 + rdns.rdns_count * sizeof(struct in_addr)) > sizeof(struct sockaddr_rtdns)) fatalx("%s: rdns_count too big: %zu", __func__, rdns.rdns_count); if (rdns.rdns_count > MAX_RDNS_COUNT) fatalx("%s: rdns_count too big: %zu", __func__, rdns.rdns_count); propose_rdns(&rdns); break; } case IMSG_WITHDRAW_RDNS: { struct imsg_propose_rdns rdns; if (imsg_get_data(&imsg, &rdns, sizeof(rdns)) == -1) fatalx("%s: invalid %s", __func__, i2s(type)); if (rdns.rdns_count != 0) fatalx("%s: expected rdns_count == 0: %zu", __func__, rdns.rdns_count); propose_rdns(&rdns); break; } default: log_debug("%s: error handling imsg %d", __func__, type); break; } imsg_free(&imsg); } if (!shut) imsg_event_add(iev); else { /* This pipe is dead. Remove its event handler. */ event_del(&iev->ev); event_loopexit(NULL); } } int main_imsg_compose_frontend(int type, int fd, void *data, uint16_t datalen) { if (iev_frontend) return (imsg_compose_event(iev_frontend, type, 0, 0, fd, data, datalen)); else return (-1); } int main_imsg_compose_engine(int type, int fd, void *data, uint16_t datalen) { if (iev_engine) return(imsg_compose_event(iev_engine, type, 0, 0, fd, data, datalen)); else return (-1); } void imsg_event_add(struct imsgev *iev) { iev->events = EV_READ; if (imsgbuf_queuelen(&iev->ibuf) > 0) iev->events |= EV_WRITE; event_del(&iev->ev); event_set(&iev->ev, iev->ibuf.fd, iev->events, iev->handler, iev); event_add(&iev->ev, NULL); } int imsg_compose_event(struct imsgev *iev, uint16_t type, uint32_t peerid, pid_t pid, int fd, void *data, uint16_t datalen) { int ret; if ((ret = imsg_compose(&iev->ibuf, type, peerid, pid, fd, data, datalen)) != -1) imsg_event_add(iev); return (ret); } int imsg_forward_event(struct imsgev *iev, struct imsg *imsg) { int ret; if ((ret = imsg_forward(&iev->ibuf, imsg)) != -1) imsg_event_add(iev); return (ret); } static int main_imsg_send_ipc_sockets(struct imsgbuf *frontend_buf, struct imsgbuf *engine_buf) { int pipe_frontend2engine[2]; if (socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC | SOCK_NONBLOCK, PF_UNSPEC, pipe_frontend2engine) == -1) return (-1); if (imsg_compose(frontend_buf, IMSG_SOCKET_IPC, 0, 0, pipe_frontend2engine[0], NULL, 0) == -1) return (-1); imsgbuf_flush(frontend_buf); if (imsg_compose(engine_buf, IMSG_SOCKET_IPC, 0, 0, pipe_frontend2engine[1], NULL, 0) == -1) return (-1); imsgbuf_flush(engine_buf); return (0); } #ifndef SMALL int main_reload(void) { struct dhcpleased_conf *xconf; if ((xconf = parse_config(conffile)) == NULL) return (-1); if (main_imsg_send_config(xconf) == -1) return (-1); merge_config(main_conf, xconf); return (0); } int main_imsg_send_config(struct dhcpleased_conf *xconf) { struct iface_conf *iface_conf; struct imsg_iface_conf imsg_iface_conf; main_imsg_compose_frontend(IMSG_RECONF_CONF, -1, NULL, 0); main_imsg_compose_engine(IMSG_RECONF_CONF, -1, NULL, 0); /* Send the interface list to the frontend & engine. */ SIMPLEQ_FOREACH(iface_conf, &xconf->iface_list, entry) { memset(&imsg_iface_conf, 0, sizeof(imsg_iface_conf)); memcpy(imsg_iface_conf.name, iface_conf->name, sizeof(imsg_iface_conf.name)); imsg_iface_conf.ignore = iface_conf->ignore; memcpy(imsg_iface_conf.ignore_servers, iface_conf->ignore_servers, sizeof(imsg_iface_conf.ignore_servers)); imsg_iface_conf.ignore_servers_len = iface_conf->ignore_servers_len; imsg_iface_conf.prefer_ipv6 = iface_conf->prefer_ipv6; main_imsg_compose_frontend(IMSG_RECONF_IFACE, -1, &imsg_iface_conf, sizeof(imsg_iface_conf)); main_imsg_compose_engine(IMSG_RECONF_IFACE, -1, &imsg_iface_conf, sizeof(imsg_iface_conf)); if (iface_conf->vc_id_len) { main_imsg_compose_frontend(IMSG_RECONF_VC_ID, -1, iface_conf->vc_id, iface_conf->vc_id_len); main_imsg_compose_engine(IMSG_RECONF_VC_ID, -1, iface_conf->vc_id, iface_conf->vc_id_len); } if (iface_conf->c_id_len) { main_imsg_compose_frontend(IMSG_RECONF_C_ID, -1, iface_conf->c_id, iface_conf->c_id_len); main_imsg_compose_engine(IMSG_RECONF_C_ID, -1, iface_conf->c_id, iface_conf->c_id_len); } if (iface_conf->h_name != NULL) main_imsg_compose_frontend(IMSG_RECONF_H_NAME, -1, iface_conf->h_name, strlen(iface_conf->h_name) + 1); } /* Config is now complete. */ main_imsg_compose_frontend(IMSG_RECONF_END, -1, NULL, 0); main_imsg_compose_engine(IMSG_RECONF_END, -1, NULL, 0); return (0); } #endif /* SMALL */ void configure_interface(struct imsg_configure_interface *imsg) { struct ifaliasreq ifaliasreq; struct ifaddrs *ifap, *ifa; struct sockaddr_in *req_sin_addr, *req_sin_mask; int found = 0, udpsock, opt = 1, len, fd = -1; char *if_name; char ip_ntop_buf[INET_ADDRSTRLEN]; char nextserver_ntop_buf[INET_ADDRSTRLEN]; char lease_buf[LEASE_SIZE]; char lease_file_buf[sizeof(_PATH_LEASE) + IF_NAMESIZE]; char tmpl[] = _PATH_LEASE"XXXXXXXXXX"; memset(&ifaliasreq, 0, sizeof(ifaliasreq)); if_name = if_indextoname(imsg->if_index, ifaliasreq.ifra_name); if (if_name == NULL) { log_warnx("%s: cannot find interface %d", __func__, imsg->if_index); return; } log_debug("%s %s", __func__, if_name); if (getifaddrs(&ifap) != 0) fatal("getifaddrs"); req_sin_addr = (struct sockaddr_in *)&ifaliasreq.ifra_addr; req_sin_addr->sin_family = AF_INET; req_sin_addr->sin_len = sizeof(*req_sin_addr); for (ifa = ifap; ifa != NULL; ifa = ifa->ifa_next) { struct in_addr addr, mask; if (strcmp(if_name, ifa->ifa_name) != 0) continue; if (ifa->ifa_addr == NULL) continue; if (ifa->ifa_addr->sa_family != AF_INET) continue; addr = ((struct sockaddr_in *)ifa->ifa_addr)->sin_addr; mask = ((struct sockaddr_in *)ifa->ifa_netmask)->sin_addr; if (imsg->addr.s_addr == addr.s_addr) { if (imsg->mask.s_addr == mask.s_addr) found = 1; else { req_sin_addr->sin_addr = addr; if (ioctl(ioctl_sock, SIOCDIFADDR, &ifaliasreq) == -1) { if (errno != EADDRNOTAVAIL) log_warn("SIOCDIFADDR"); } } break; } } freeifaddrs(ifap); req_sin_addr->sin_addr = imsg->addr; if (!found) { req_sin_mask = (struct sockaddr_in *)&ifaliasreq.ifra_mask; req_sin_mask->sin_family = AF_INET; req_sin_mask->sin_len = sizeof(*req_sin_mask); req_sin_mask->sin_addr = imsg->mask; if (ioctl(ioctl_sock, SIOCAIFADDR, &ifaliasreq) == -1) log_warn("SIOCAIFADDR"); } if (imsg->routes_len > 0) configure_routes(RTM_ADD, imsg); req_sin_addr->sin_port = ntohs(CLIENT_PORT); if ((udpsock = socket(AF_INET, SOCK_DGRAM, 0)) == -1) { log_warn("socket"); return; } if (setsockopt(udpsock, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt)) == -1) log_warn("setting SO_REUSEADDR on socket"); if (setsockopt(udpsock, SOL_SOCKET, SO_RTABLE, &imsg->rdomain, sizeof(imsg->rdomain)) == -1) { /* we might race against removal of the rdomain */ log_warn("setsockopt SO_RTABLE"); close(udpsock); return; } if (bind(udpsock, (struct sockaddr *)req_sin_addr, sizeof(*req_sin_addr)) == -1) { close(udpsock); return; } shutdown(udpsock, SHUT_RD); main_imsg_compose_frontend(IMSG_UDPSOCK, udpsock, &imsg->if_index, sizeof(imsg->if_index)); if (no_lease_files) return; if (inet_ntop(AF_INET, &imsg->addr, ip_ntop_buf, sizeof(ip_ntop_buf)) == NULL) { log_warn("%s: inet_ntop", __func__); return; } if (imsg->siaddr.s_addr == INADDR_ANY) nextserver_ntop_buf[0] = '\0'; else { if (inet_ntop(AF_INET, &imsg->siaddr, nextserver_ntop_buf, sizeof(nextserver_ntop_buf)) == NULL) { log_warn("%s: inet_ntop", __func__); return; } } len = snprintf(lease_file_buf, sizeof(lease_file_buf), "%s%s", _PATH_LEASE, if_name); if ( len == -1 || (size_t) len >= sizeof(lease_file_buf)) { log_warnx("%s: failed to encode lease path for %s", __func__, if_name); return; } len = snprintf(lease_buf, sizeof(lease_buf), "%s\n%s%s\n%s%s\n%s%s\n%s%s\n%s%s\n", LEASE_VERSION, LEASE_IP_PREFIX, ip_ntop_buf, LEASE_NEXTSERVER_PREFIX, nextserver_ntop_buf, LEASE_BOOTFILE_PREFIX, imsg->file, LEASE_HOSTNAME_PREFIX, imsg->hostname, LEASE_DOMAIN_PREFIX, imsg->domainname); if ( len == -1 || (size_t) len >= sizeof(lease_buf)) { log_warnx("%s: failed to encode lease for %s", __func__, ip_ntop_buf); return; } if ((fd = mkstemp(tmpl)) == -1) { log_warn("%s: mkstemp", __func__); return; } if (write(fd, lease_buf, len) < len) goto err; if (fchmod(fd, 0644) == -1) goto err; if (close(fd) == -1) goto err; fd = -1; if (rename(tmpl, lease_file_buf) == -1) goto err; return; err: log_warn("%s", __func__); if (fd != -1) close(fd); unlink(tmpl); } void deconfigure_interface(struct imsg_configure_interface *imsg) { struct ifaliasreq ifaliasreq; struct sockaddr_in *req_sin_addr; memset(&ifaliasreq, 0, sizeof(ifaliasreq)); #if 0 /* * When two default routes have the same gateway the kernel always * deletes the first which might be the wrong one. When we then * deconfigure the IP address from the interface the kernel deletes * all routes pointing out that interface and we end up with no * default. * This can happen with a wired & wireless interface on the same * layer 2 network and the user issues ifconfig $WIFI inet -autoconf. * Work around this issue by not deleting the default route and let * the kernel handle it when we remove the IP address a few lines * down. */ if (imsg->routes_len > 0) configure_routes(RTM_DELETE, imsg); #endif if (if_indextoname(imsg->if_index, ifaliasreq.ifra_name) == NULL) { log_warnx("%s: cannot find interface %d", __func__, imsg->if_index); return; } log_debug("%s %s", __func__, ifaliasreq.ifra_name); req_sin_addr = (struct sockaddr_in *)&ifaliasreq.ifra_addr; req_sin_addr->sin_family = AF_INET; req_sin_addr->sin_len = sizeof(*req_sin_addr); req_sin_addr->sin_addr = imsg->addr; if (ioctl(ioctl_sock, SIOCDIFADDR, &ifaliasreq) == -1) { if (errno != EADDRNOTAVAIL) log_warn("SIOCDIFADDR"); } } void configure_routes(uint8_t rtm_type, struct imsg_configure_interface *imsg) { struct sockaddr_in dst, mask, gw, ifa; in_addr_t addrnet, gwnet; int i; memset(&ifa, 0, sizeof(ifa)); ifa.sin_family = AF_INET; ifa.sin_len = sizeof(ifa); ifa.sin_addr = imsg->addr; memset(&dst, 0, sizeof(dst)); dst.sin_family = AF_INET; dst.sin_len = sizeof(dst); memset(&mask, 0, sizeof(mask)); mask.sin_family = AF_INET; mask.sin_len = sizeof(mask); memset(&gw, 0, sizeof(gw)); gw.sin_family = AF_INET; gw.sin_len = sizeof(gw); addrnet = imsg->addr.s_addr & imsg->mask.s_addr; for (i = 0; i < imsg->routes_len; i++) { dst.sin_addr = imsg->routes[i].dst; mask.sin_addr = imsg->routes[i].mask; gw.sin_addr = imsg->routes[i].gw; if (gw.sin_addr.s_addr == INADDR_ANY) { /* direct route */ configure_route(rtm_type, imsg->if_index, imsg->rdomain, &dst, &mask, &ifa, NULL, RTF_CLONING); } else if (mask.sin_addr.s_addr == INADDR_ANY) { /* default route */ gwnet = gw.sin_addr.s_addr & imsg->mask.s_addr; if (addrnet != gwnet) { /* * The gateway for the default route is outside * the configured prefix. Install a direct * cloning route for the gateway to make the * default route reachable. */ mask.sin_addr.s_addr = 0xffffffff; configure_route(rtm_type, imsg->if_index, imsg->rdomain, &gw, &mask, &ifa, NULL, RTF_CLONING); mask.sin_addr = imsg->routes[i].mask; } if (gw.sin_addr.s_addr == ifa.sin_addr.s_addr) { /* directly connected default */ configure_route(rtm_type, imsg->if_index, imsg->rdomain, &dst, &mask, &gw, NULL, 0); } else { /* default route via gateway */ configure_route(rtm_type, imsg->if_index, imsg->rdomain, &dst, &mask, &gw, &ifa, RTF_GATEWAY); } } else { /* non-default via gateway */ configure_route(rtm_type, imsg->if_index, imsg->rdomain, &dst, &mask, &gw, NULL, RTF_GATEWAY); } } } #define ROUNDUP(a) \ (((a) & (sizeof(long) - 1)) ? (1 + ((a) | (sizeof(long) - 1))) : (a)) void configure_route(uint8_t rtm_type, uint32_t if_index, int rdomain, struct sockaddr_in *dst, struct sockaddr_in *mask, struct sockaddr_in *gw, struct sockaddr_in *ifa, int rtm_flags) { struct rt_msghdr rtm; struct sockaddr_dl ifp; struct sockaddr_rtlabel rl; struct iovec iov[14]; long pad = 0; int iovcnt = 0, padlen; memset(&rtm, 0, sizeof(rtm)); rtm.rtm_version = RTM_VERSION; rtm.rtm_type = rtm_type; rtm.rtm_msglen = sizeof(rtm); rtm.rtm_index = if_index; rtm.rtm_tableid = rdomain; rtm.rtm_seq = ++rtm_seq; rtm.rtm_priority = RTP_NONE; rtm.rtm_addrs = RTA_DST | RTA_GATEWAY | RTA_NETMASK | RTA_IFP | RTA_LABEL; rtm.rtm_flags = RTF_UP | RTF_STATIC | RTF_MPATH | rtm_flags; if (ifa) rtm.rtm_addrs |= RTA_IFA; iov[iovcnt].iov_base = &rtm; iov[iovcnt++].iov_len = sizeof(rtm); iov[iovcnt].iov_base = dst; iov[iovcnt++].iov_len = dst->sin_len; rtm.rtm_msglen += dst->sin_len; padlen = ROUNDUP(dst->sin_len) - dst->sin_len; if (padlen > 0) { iov[iovcnt].iov_base = &pad; iov[iovcnt++].iov_len = padlen; rtm.rtm_msglen += padlen; } iov[iovcnt].iov_base = gw; iov[iovcnt++].iov_len = gw->sin_len; rtm.rtm_msglen += gw->sin_len; padlen = ROUNDUP(gw->sin_len) - gw->sin_len; if (padlen > 0) { iov[iovcnt].iov_base = &pad; iov[iovcnt++].iov_len = padlen; rtm.rtm_msglen += padlen; } iov[iovcnt].iov_base = mask; iov[iovcnt++].iov_len = mask->sin_len; rtm.rtm_msglen += mask->sin_len; padlen = ROUNDUP(mask->sin_len) - mask->sin_len; if (padlen > 0) { iov[iovcnt].iov_base = &pad; iov[iovcnt++].iov_len = padlen; rtm.rtm_msglen += padlen; } memset(&ifp, 0, sizeof(ifp)); ifp.sdl_len = sizeof(struct sockaddr_dl); ifp.sdl_family = AF_LINK; ifp.sdl_index = if_index; iov[iovcnt].iov_base = &ifp; iov[iovcnt++].iov_len = sizeof(ifp); rtm.rtm_msglen += sizeof(ifp); padlen = ROUNDUP(sizeof(ifp)) - sizeof(ifp); if (padlen > 0) { iov[iovcnt].iov_base = &pad; iov[iovcnt++].iov_len = padlen; rtm.rtm_msglen += padlen; } if (ifa) { iov[iovcnt].iov_base = ifa; iov[iovcnt++].iov_len = ifa->sin_len; rtm.rtm_msglen += ifa->sin_len; padlen = ROUNDUP(ifa->sin_len) - ifa->sin_len; if (padlen > 0) { iov[iovcnt].iov_base = &pad; iov[iovcnt++].iov_len = padlen; rtm.rtm_msglen += padlen; } } memset(&rl, 0, sizeof(rl)); rl.sr_len = sizeof(rl); rl.sr_family = AF_UNSPEC; (void)snprintf(rl.sr_label, sizeof(rl.sr_label), "%s", DHCPLEASED_RTA_LABEL); iov[iovcnt].iov_base = &rl; iov[iovcnt++].iov_len = sizeof(rl); rtm.rtm_msglen += sizeof(rl); padlen = ROUNDUP(sizeof(rl)) - sizeof(rl); if (padlen > 0) { iov[iovcnt].iov_base = &pad; iov[iovcnt++].iov_len = padlen; rtm.rtm_msglen += padlen; } if (writev(routesock, iov, iovcnt) == -1) { if (errno != EEXIST) log_warn("failed to send route message"); } } #ifndef SMALL const char* sin_to_str(struct sockaddr_in *sin) { static char hbuf[NI_MAXHOST]; int error; error = getnameinfo((struct sockaddr *)sin, sin->sin_len, hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST | NI_NUMERICSERV); if (error) { log_warnx("%s", gai_strerror(error)); strlcpy(hbuf, "unknown", sizeof(hbuf)); } return hbuf; } #endif /* SMALL */ void open_bpfsock(uint32_t if_index) { int bpfsock; char ifname[IF_NAMESIZE]; if (if_indextoname(if_index, ifname) == NULL) { log_warnx("%s: cannot find interface %d", __func__, if_index); return; } if ((bpfsock = get_bpf_sock(ifname)) == -1) return; main_imsg_compose_frontend(IMSG_BPFSOCK, bpfsock, &if_index, sizeof(if_index)); } void propose_rdns(struct imsg_propose_rdns *rdns) { struct rt_msghdr rtm; struct sockaddr_rtdns rtdns; struct iovec iov[3]; long pad = 0; int iovcnt = 0, padlen; memset(&rtm, 0, sizeof(rtm)); rtm.rtm_version = RTM_VERSION; rtm.rtm_type = RTM_PROPOSAL; rtm.rtm_msglen = sizeof(rtm); rtm.rtm_tableid = rdns->rdomain; rtm.rtm_index = rdns->if_index; rtm.rtm_seq = ++rtm_seq; rtm.rtm_priority = RTP_PROPOSAL_DHCLIENT; rtm.rtm_addrs = RTA_DNS; rtm.rtm_flags = RTF_UP; iov[iovcnt].iov_base = &rtm; iov[iovcnt++].iov_len = sizeof(rtm); memset(&rtdns, 0, sizeof(rtdns)); rtdns.sr_family = AF_INET; rtdns.sr_len = 2 + rdns->rdns_count * sizeof(struct in_addr); memcpy(rtdns.sr_dns, rdns->rdns, rtdns.sr_len - 2); iov[iovcnt].iov_base = &rtdns; iov[iovcnt++].iov_len = sizeof(rtdns); rtm.rtm_msglen += sizeof(rtdns); padlen = ROUNDUP(sizeof(rtdns)) - sizeof(rtdns); if (padlen > 0) { iov[iovcnt].iov_base = &pad; iov[iovcnt++].iov_len = padlen; rtm.rtm_msglen += padlen; } if (writev(routesock, iov, iovcnt) == -1) log_warn("failed to propose nameservers"); } void read_lease_file(struct imsg_ifinfo *imsg_ifinfo) { int len, fd; char if_name[IF_NAMESIZE]; char lease_file_buf[sizeof(_PATH_LEASE) + IF_NAMESIZE]; if (no_lease_files) return; memset(imsg_ifinfo->lease, 0, sizeof(imsg_ifinfo->lease)); if (if_indextoname(imsg_ifinfo->if_index, if_name) == NULL) { log_warnx("%s: cannot find interface %d", __func__, imsg_ifinfo->if_index); return; } len = snprintf(lease_file_buf, sizeof(lease_file_buf), "%s%s", _PATH_LEASE, if_name); if ( len == -1 || (size_t) len >= sizeof(lease_file_buf)) { log_warnx("%s: failed to encode lease path for %s", __func__, if_name); return; } if ((fd = open(lease_file_buf, O_RDONLY)) == -1) return; /* no need for error handling, we'll just do a DHCP discover */ read(fd, imsg_ifinfo->lease, sizeof(imsg_ifinfo->lease) - 1); close(fd); } #ifndef SMALL void merge_config(struct dhcpleased_conf *conf, struct dhcpleased_conf *xconf) { struct iface_conf *iface_conf; /* Remove & discard existing interfaces. */ while ((iface_conf = SIMPLEQ_FIRST(&conf->iface_list)) != NULL) { SIMPLEQ_REMOVE_HEAD(&conf->iface_list, entry); free(iface_conf->vc_id); free(iface_conf->c_id); free(iface_conf->h_name); free(iface_conf); } /* Add new interfaces. */ SIMPLEQ_CONCAT(&conf->iface_list, &xconf->iface_list); free(xconf); } struct dhcpleased_conf * config_new_empty(void) { struct dhcpleased_conf *xconf; xconf = calloc(1, sizeof(*xconf)); if (xconf == NULL) fatal(NULL); SIMPLEQ_INIT(&xconf->iface_list); return (xconf); } void config_clear(struct dhcpleased_conf *conf) { struct dhcpleased_conf *xconf; /* Merge current config with an empty config. */ xconf = config_new_empty(); merge_config(conf, xconf); free(conf); } #define I2S(x) case x: return #x const char* i2s(uint32_t type) { static char unknown[sizeof("IMSG_4294967295")]; switch (type) { I2S(IMSG_NONE); I2S(IMSG_CTL_LOG_VERBOSE); I2S(IMSG_CTL_SHOW_INTERFACE_INFO); I2S(IMSG_CTL_SEND_REQUEST); I2S(IMSG_CTL_RELOAD); I2S(IMSG_CTL_END); I2S(IMSG_RECONF_CONF); I2S(IMSG_RECONF_IFACE); I2S(IMSG_RECONF_VC_ID); I2S(IMSG_RECONF_C_ID); I2S(IMSG_RECONF_H_NAME); I2S(IMSG_RECONF_END); I2S(IMSG_SEND_DISCOVER); I2S(IMSG_SEND_REQUEST); I2S(IMSG_SOCKET_IPC); I2S(IMSG_OPEN_BPFSOCK); I2S(IMSG_BPFSOCK); I2S(IMSG_UDPSOCK); I2S(IMSG_CLOSE_UDPSOCK); I2S(IMSG_ROUTESOCK); I2S(IMSG_CONTROLFD); I2S(IMSG_STARTUP); I2S(IMSG_UPDATE_IF); I2S(IMSG_REMOVE_IF); I2S(IMSG_DHCP); I2S(IMSG_CONFIGURE_INTERFACE); I2S(IMSG_DECONFIGURE_INTERFACE); I2S(IMSG_PROPOSE_RDNS); I2S(IMSG_WITHDRAW_RDNS); I2S(IMSG_WITHDRAW_ROUTES); I2S(IMSG_REPROPOSE_RDNS); I2S(IMSG_REQUEST_REBOOT); default: snprintf(unknown, sizeof(unknown), "IMSG_%u", type); return unknown; } } #undef I2S #endif /* SMALL */