/* * dhcpcd - DHCP client daemon * Copyright (c) 2006-2014 Roy Marples * All rights reserved * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ const char dhcpcd_copyright[] = "Copyright (c) 2006-2014 Roy Marples"; #define _WITH_DPRINTF /* Stop FreeBSD bitching */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "config.h" #include "arp.h" #include "common.h" #include "control.h" #include "dev.h" #include "dhcpcd.h" #include "dhcp6.h" #include "duid.h" #include "eloop.h" #include "if-options.h" #include "if-pref.h" #include "ipv4.h" #include "ipv6.h" #include "ipv6nd.h" #include "net.h" #include "platform.h" #include "script.h" #ifdef USE_SIGNALS const int handle_sigs[] = { SIGALRM, SIGHUP, SIGINT, SIGPIPE, SIGTERM, SIGUSR1, 0 }; /* Handling signals needs *some* context */ static struct dhcpcd_ctx *dhcpcd_ctx; #endif #if defined(USE_SIGNALS) || !defined(THERE_IS_NO_FORK) static pid_t read_pid(const char *pidfile) { FILE *fp; pid_t pid; if ((fp = fopen(pidfile, "r")) == NULL) { errno = ENOENT; return 0; } if (fscanf(fp, "%d", &pid) != 1) pid = 0; fclose(fp); return pid; } static inline int write_pid(int fd, pid_t pid) { if (ftruncate(fd, (off_t)0) == -1) return -1; lseek(fd, (off_t)0, SEEK_SET); return dprintf(fd, "%d\n", (int)pid); } #endif static void usage(void) { printf("usage: "PACKAGE"\t[-46ABbDdEGgHJKkLnpqTVw]\n" "\t\t[-C, --nohook hook] [-c, --script script]\n" "\t\t[-e, --env value] [-F, --fqdn FQDN] [-f, --config file]\n" "\t\t[-h, --hostname hostname] [-I, --clientid clientid]\n" "\t\t[-i, --vendorclassid vendorclassid] [-l, --leasetime seconds]\n" "\t\t[-m, --metric metric] [-O, --nooption option]\n" "\t\t[-o, --option option] [-Q, --require option]\n" "\t\t[-r, --request address] [-S, --static value]\n" "\t\t[-s, --inform address[/cidr]] [-t, --timeout seconds]\n" "\t\t[-u, --userclass class] [-v, --vendor code, value]\n" "\t\t[-W, --whitelist address[/cidr]] [-y, --reboot seconds]\n" "\t\t[-X, --blacklist address[/cidr]] [-Z, --denyinterfaces pattern]\n" "\t\t[-z, --allowinterfaces pattern] [interface] [...]\n" " "PACKAGE"\t-k, --release [interface]\n" " "PACKAGE"\t-U, --dumplease interface\n" " "PACKAGE"\t--version\n" " "PACKAGE"\t-x, --exit [interface]\n"); } static void free_globals(struct dhcpcd_ctx *ctx) { struct dhcp_opt *opt; if (ctx->ifac) { for (ctx->ifac--; ctx->ifac >= 0; ctx->ifac--) free(ctx->ifav[ctx->ifac]); free(ctx->ifav); ctx->ifav = NULL; } if (ctx->ifdc) { for (ctx->ifdc--; ctx->ifdc >= 0; ctx->ifdc--) free(ctx->ifdv[ctx->ifdc]); free(ctx->ifdv); ctx->ifdv = NULL; } #ifdef INET if (ctx->dhcp_opts) { for (opt = ctx->dhcp_opts; ctx->dhcp_opts_len > 0; opt++, ctx->dhcp_opts_len--) free_dhcp_opt_embenc(opt); free(ctx->dhcp_opts); ctx->dhcp_opts = NULL; } #endif #ifdef INET6 if (ctx->dhcp6_opts) { for (opt = ctx->dhcp6_opts; ctx->dhcp6_opts_len > 0; opt++, ctx->dhcp6_opts_len--) free_dhcp_opt_embenc(opt); free(ctx->dhcp6_opts); ctx->dhcp6_opts = NULL; } #endif if (ctx->vivso) { for (opt = ctx->vivso; ctx->vivso_len > 0; opt++, ctx->vivso_len--) free_dhcp_opt_embenc(opt); free(ctx->vivso); ctx->vivso = NULL; } } static void handle_exit_timeout(void *arg) { struct dhcpcd_ctx *ctx; int timeout; ctx = arg; syslog(LOG_ERR, "timed out"); if (!(ctx->options & DHCPCD_IPV4) || !(ctx->options & DHCPCD_TIMEOUT_IPV4LL)) { if (ctx->options & DHCPCD_MASTER) { /* We've timed out, so remove the waitip requirements. * If the user doesn't like this they can always set * an infinite timeout. */ ctx->options &= ~(DHCPCD_WAITIP | DHCPCD_WAITIP4 | DHCPCD_WAITIP6); daemonise(ctx); } else eloop_exit(ctx->eloop, EXIT_FAILURE); return; } ctx->options &= ~DHCPCD_TIMEOUT_IPV4LL; timeout = (PROBE_NUM * PROBE_MAX) + (PROBE_WAIT * 2); syslog(LOG_WARNING, "allowing %d seconds for IPv4LL timeout", timeout); eloop_timeout_add_sec(ctx->eloop, timeout, handle_exit_timeout, ctx); } /* Returns the pid of the child, otherwise 0. */ pid_t daemonise(struct dhcpcd_ctx *ctx) { #ifdef THERE_IS_NO_FORK eloop_timeout_delete(ctx->eloop, handle_exit_timeout, ctx); errno = ENOSYS; return 0; #else pid_t pid; char buf = '\0'; int sidpipe[2], fd; if (ctx->options & DHCPCD_DAEMONISE && !(ctx->options & DHCPCD_DAEMONISED)) { if (ctx->options & DHCPCD_WAITIP4 && !ipv4_addrexists(ctx, NULL)) return 0; if (ctx->options & DHCPCD_WAITIP6 && !ipv6nd_addrexists(ctx, NULL) && !dhcp6_addrexists(ctx, NULL)) return 0; if ((ctx->options & (DHCPCD_WAITIP | DHCPCD_WAITIP4 | DHCPCD_WAITIP6)) == (DHCPCD_WAITIP | DHCPCD_WAITIP4 | DHCPCD_WAITIP6) && !ipv4_addrexists(ctx, NULL) && !ipv6nd_addrexists(ctx, NULL) && !dhcp6_addrexists(ctx, NULL)) return 0; } eloop_timeout_delete(ctx->eloop, handle_exit_timeout, ctx); if (ctx->options & DHCPCD_DAEMONISED || !(ctx->options & DHCPCD_DAEMONISE)) return 0; /* Setup a signal pipe so parent knows when to exit. */ if (pipe(sidpipe) == -1) { syslog(LOG_ERR, "pipe: %m"); return 0; } syslog(LOG_DEBUG, "forking to background"); switch (pid = fork()) { case -1: syslog(LOG_ERR, "fork: %m"); return 0; case 0: setsid(); /* Notify parent it's safe to exit as we've detached. */ close(sidpipe[0]); if (write(sidpipe[1], &buf, 1) == -1) syslog(LOG_ERR, "failed to notify parent: %m"); close(sidpipe[1]); if ((fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) { dup2(fd, STDIN_FILENO); dup2(fd, STDOUT_FILENO); dup2(fd, STDERR_FILENO); close(fd); } break; default: /* Wait for child to detach */ close(sidpipe[1]); if (read(sidpipe[0], &buf, 1) == -1) syslog(LOG_ERR, "failed to read child: %m"); close(sidpipe[0]); break; } /* Done with the fd now */ if (pid != 0) { syslog(LOG_INFO, "forked to background, child pid %d", pid); write_pid(ctx->pid_fd, pid); close(ctx->pid_fd); ctx->pid_fd = -1; ctx->options |= DHCPCD_FORKED; eloop_exit(ctx->eloop, EXIT_SUCCESS); return pid; } ctx->options |= DHCPCD_DAEMONISED; return pid; #endif } struct interface * find_interface(struct dhcpcd_ctx *ctx, const char *ifname) { struct interface *ifp; if (ctx != NULL && ctx->ifaces != NULL) { TAILQ_FOREACH(ifp, ctx->ifaces, next) { if (strcmp(ifp->name, ifname) == 0) return ifp; } } return NULL; } static void stop_interface(struct interface *ifp) { struct dhcpcd_ctx *ctx; ctx = ifp->ctx; syslog(LOG_INFO, "%s: removing interface", ifp->name); ifp->options->options |= DHCPCD_STOPPING; // Remove the interface from our list TAILQ_REMOVE(ifp->ctx->ifaces, ifp, next); dhcp6_drop(ifp, NULL); ipv6nd_drop(ifp); dhcp_drop(ifp, "STOP"); eloop_timeout_delete(ctx->eloop, NULL, ifp); if (ifp->options->options & DHCPCD_DEPARTED) script_runreason(ifp, "DEPARTED"); free_interface(ifp); if (!(ctx->options & (DHCPCD_MASTER | DHCPCD_TEST))) eloop_exit(ctx->eloop, EXIT_FAILURE); } static void configure_interface1(struct interface *ifp) { struct if_options *ifo = ifp->options; int ra_global, ra_iface; /* Do any platform specific configuration */ if_conf(ifp); /* If we want to release a lease, we can't really persist the * address either. */ if (ifo->options & DHCPCD_RELEASE) ifo->options &= ~DHCPCD_PERSISTENT; if (ifp->flags & IFF_POINTOPOINT && !(ifo->options & DHCPCD_INFORM)) ifo->options |= DHCPCD_STATIC; if (ifp->flags & IFF_NOARP || ifo->options & (DHCPCD_INFORM | DHCPCD_STATIC)) ifo->options &= ~(DHCPCD_ARP | DHCPCD_IPV4LL); if (!(ifp->flags & (IFF_POINTOPOINT | IFF_LOOPBACK | IFF_MULTICAST))) ifo->options &= ~DHCPCD_IPV6RS; if (ifo->options & DHCPCD_LINK && carrier_status(ifp) == LINK_UNKNOWN) ifo->options &= ~DHCPCD_LINK; if (ifo->metric != -1) ifp->metric = (unsigned int)ifo->metric; if (!(ifo->options & DHCPCD_IPV6)) ifo->options &= ~DHCPCD_IPV6RS; /* We want to disable kernel interface RA as early as possible. */ if (ifo->options & DHCPCD_IPV6RS) { ra_global = check_ipv6(ifp->ctx, NULL, ifp->ctx->options & DHCPCD_IPV6RA_OWN ? 1 : 0); ra_iface = check_ipv6(ifp->ctx, ifp->name, ifp->options->options & DHCPCD_IPV6RA_OWN ? 1 : 0); if (ra_global == -1 || ra_iface == -1) ifo->options &= ~DHCPCD_IPV6RS; else if (ra_iface == 0) ifo->options |= DHCPCD_IPV6RA_OWN; } /* If we haven't specified a ClientID and our hardware address * length is greater than DHCP_CHADDR_LEN then we enforce a ClientID * of the hardware address family and the hardware address. */ if (ifp->hwlen > DHCP_CHADDR_LEN) ifo->options |= DHCPCD_CLIENTID; /* Firewire and InfiniBand interfaces require ClientID and * the broadcast option being set. */ switch (ifp->family) { case ARPHRD_IEEE1394: /* FALLTHROUGH */ case ARPHRD_INFINIBAND: ifo->options |= DHCPCD_CLIENTID | DHCPCD_BROADCAST; break; } if (!(ifo->options & DHCPCD_IAID)) { /* * An IAID is for identifying a unqiue interface within * the client. It is 4 bytes long. Working out a default * value is problematic. * * Interface name and number are not stable * between different OS's. Some OS's also cannot make * up their mind what the interface should be called * (yes, udev, I'm looking at you). * Also, the name could be longer than 4 bytes. * Also, with pluggable interfaces the name and index * could easily get swapped per actual interface. * * The MAC address is 6 bytes long, the final 3 * being unique to the manufacturer and the initial 3 * being unique to the organisation which makes it. * We could use the last 4 bytes of the MAC address * as the IAID as it's the most stable part given the * above, but equally it's not guaranteed to be * unique. * * Given the above, and our need to reliably work * between reboots without persitent storage, * generating the IAID from the MAC address is the only * logical default. * * dhclient uses the last 4 bytes of the MAC address. * dibbler uses an increamenting counter. * wide-dhcpv6 uses 0 or a configured value. * odhcp6c uses 1. * Windows 7 uses the first 3 bytes of the MAC address * and an unknown byte. * dhcpcd-6.1.0 and earlier used the interface name, * falling back to interface index if name > 4. */ memcpy(ifo->iaid, ifp->hwaddr + ifp->hwlen - sizeof(ifo->iaid), sizeof(ifo->iaid)); #if 0 len = strlen(ifp->name); if (len <= sizeof(ifo->iaid)) { memcpy(ifo->iaid, ifp->name, len); memset(ifo->iaid + len, 0, sizeof(ifo->iaid) - len); } else { /* IAID is the same size as a uint32_t */ len = htonl(ifp->index); memcpy(ifo->iaid, &len, sizeof(len)); } #endif ifo->options |= DHCPCD_IAID; } #ifdef INET6 if (ifo->ia == NULL && ifo->options & DHCPCD_IPV6) { ifo->ia = malloc(sizeof(*ifo->ia)); if (ifo->ia == NULL) syslog(LOG_ERR, "%s: %m", __func__); else { if (ifo->ia_type == 0) ifo->ia_type = D6_OPTION_IA_NA; memcpy(ifo->ia->iaid, ifo->iaid, sizeof(ifo->iaid)); ifo->ia_len = 1; ifo->ia->sla = NULL; ifo->ia->sla_len = 0; } } #endif /* If we are not sending an authentication option, don't require it */ if (!(ifo->auth.options & DHCPCD_AUTH_SEND)) ifo->auth.options &= ~DHCPCD_AUTH_REQUIRE; } int select_profile(struct interface *ifp, const char *profile) { struct if_options *ifo; ifo = read_config(ifp->ctx, ifp->name, ifp->ssid, profile); if (ifo == NULL) { syslog(LOG_DEBUG, "%s: no profile %s", ifp->name, profile); return -1; } if (profile != NULL) { strlcpy(ifp->profile, profile, sizeof(ifp->profile)); syslog(LOG_INFO, "%s: selected profile %s", ifp->name, profile); } else *ifp->profile = '\0'; free_options(ifp->options); ifp->options = ifo; if (profile) configure_interface1(ifp); return 1; } static void configure_interface(struct interface *ifp, int argc, char **argv) { select_profile(ifp, NULL); add_options(ifp->ctx, ifp->name, ifp->options, argc, argv); configure_interface1(ifp); } void handle_carrier(struct dhcpcd_ctx *ctx, int carrier, unsigned int flags, const char *ifname) { struct interface *ifp; ifp = find_interface(ctx, ifname); if (ifp == NULL || !(ifp->options->options & DHCPCD_LINK)) return; if (carrier == LINK_UNKNOWN) carrier = carrier_status(ifp); /* will set ifp->flags */ else ifp->flags = flags; if (carrier == LINK_UNKNOWN) syslog(LOG_ERR, "%s: carrier_status: %m", ifname); /* IFF_RUNNING is checked, if needed, earlier and is OS dependant */ else if (carrier == LINK_DOWN || (ifp->flags & IFF_UP) == 0) { if (ifp->carrier != LINK_DOWN) { if (ifp->carrier == LINK_UP) syslog(LOG_INFO, "%s: carrier lost", ifp->name); ifp->carrier = LINK_DOWN; dhcp6_drop(ifp, "EXPIRE6"); ipv6nd_drop(ifp); /* Don't blindly delete our knowledge of LL addresses. * We need to listen to what the kernel does with * them as some OS's will remove, mark tentative or * do nothing. */ ipv6_free_ll_callbacks(ifp); dhcp_drop(ifp, "EXPIRE"); script_runreason(ifp, "NOCARRIER"); } } else if (carrier == LINK_UP && ifp->flags & IFF_UP) { if (ifp->carrier != LINK_UP) { syslog(LOG_INFO, "%s: carrier acquired", ifp->name); ifp->carrier = LINK_UP; #if !defined(__linux__) && !defined(__NetBSD__) /* BSD does not emit RTM_NEWADDR or RTM_CHGADDR when the * hardware address changes so we have to go * through the disovery process to work it out. */ handle_interface(ctx, 0, ifp->name); #endif if (ifp->wireless) getifssid(ifp->name, ifp->ssid); configure_interface(ifp, ctx->argc, ctx->argv); script_runreason(ifp, "CARRIER"); start_interface(ifp); } } } static void warn_iaid_conflict(struct interface *ifp, uint8_t *iaid) { struct interface *ifn; size_t i; TAILQ_FOREACH(ifn, ifp->ctx->ifaces, next) { if (ifn == ifp) continue; if (memcmp(ifn->options->iaid, iaid, sizeof(ifn->options->iaid)) == 0) break; for (i = 0; i < ifn->options->ia_len; i++) { if (memcmp(&ifn->options->ia[i].iaid, iaid, sizeof(ifn->options->ia[i].iaid)) == 0) break; } } /* This is only a problem if the interfaces are on the same network. */ if (ifn) syslog(LOG_ERR, "%s: IAID conflicts with one assigned to %s", ifp->name, ifn->name); } void start_interface(void *arg) { struct interface *ifp = arg; struct if_options *ifo = ifp->options; size_t i; char buf[DUID_LEN * 3]; if (ifp->carrier == LINK_UNKNOWN) handle_carrier(ifp->ctx, LINK_UNKNOWN, 0, ifp->name); if (ifp->carrier == LINK_DOWN) { syslog(LOG_INFO, "%s: waiting for carrier", ifp->name); return; } if (ifo->options & (DHCPCD_DUID | DHCPCD_IPV6)) { /* Report client DUID */ if (ifp->ctx->duid == NULL) { if (duid_init(ifp) == 0) return; syslog(LOG_INFO, "DUID %s", hwaddr_ntoa(ifp->ctx->duid, ifp->ctx->duid_len, buf, sizeof(buf))); } /* Report IAIDs */ syslog(LOG_INFO, "%s: IAID %s", ifp->name, hwaddr_ntoa(ifo->iaid, sizeof(ifo->iaid), buf, sizeof(buf))); warn_iaid_conflict(ifp, ifo->iaid); for (i = 0; i < ifo->ia_len; i++) { if (memcmp(ifo->iaid, ifo->ia[i].iaid, sizeof(ifo->iaid))) { syslog(LOG_INFO, "%s: IAID %s", ifp->name, hwaddr_ntoa(ifo->ia[i].iaid, sizeof(ifo->ia[i].iaid), buf, sizeof(buf))); warn_iaid_conflict(ifp, ifo->ia[i].iaid); } } } if (ifo->options & DHCPCD_IPV6) { if (ifo->options & DHCPCD_IPV6RS && !(ifo->options & DHCPCD_INFORM)) ipv6nd_startrs(ifp); if (!(ifo->options & DHCPCD_IPV6RS)) { ssize_t nolease; if (ifo->options & DHCPCD_IA_FORCED) nolease = dhcp6_start(ifp, DH6S_INIT); else { dhcp6_find_delegates(ifp); nolease = 0; /* Enabling the below doesn't really make * sense as there is currently no standard * to push routes via DHCPv6. * (There is an expired working draft, * maybe abandoned?) * You can also get it to work by forcing * an IA as shown above. */ #if 0 /* With no RS or delegates we might * as well try and solicit a DHCPv6 address */ if (nolease == 0) nolease = dhcp6_start(ifp, DH6S_INIT); #endif } if (nolease == -1) syslog(LOG_ERR, "%s: dhcp6_start: %m", ifp->name); } } if (ifo->options & DHCPCD_IPV4) dhcp_start(ifp); } static void handle_link(void *arg) { struct dhcpcd_ctx *ctx; ctx = arg; if (manage_link(ctx) == -1 && errno != ENXIO && errno != ENODEV) syslog(LOG_ERR, "manage_link: %m"); } static void init_state(struct interface *ifp, int argc, char **argv) { struct if_options *ifo; const char *reason; configure_interface(ifp, argc, argv); ifo = ifp->options; if (ifo->options & DHCPCD_IPV4 && ipv4_init(ifp->ctx) == -1) { syslog(LOG_ERR, "ipv4_init: %m"); ifo->options &= ~DHCPCD_IPV4; } if (ifo->options & DHCPCD_IPV6 && ipv6_init(ifp->ctx) == NULL) { syslog(LOG_ERR, "ipv6_init: %m"); ifo->options &= ~DHCPCD_IPV6RS; } reason = NULL; /* appease gcc */ if (ifo->options & DHCPCD_LINK) { switch (carrier_status(ifp)) { case LINK_DOWN: ifp->carrier = LINK_DOWN; reason = "NOCARRIER"; break; case LINK_UP: ifp->carrier = LINK_UP; reason = "CARRIER"; break; default: ifp->carrier = LINK_UNKNOWN; return; } } else ifp->carrier = LINK_UNKNOWN; if (!(ifp->ctx->options & DHCPCD_TEST)) script_runreason(ifp, "PREINIT"); if (ifp->carrier != LINK_UNKNOWN && !(ifp->ctx->options & DHCPCD_TEST)) script_runreason(ifp, reason); } void handle_interface(void *arg, int action, const char *ifname) { struct dhcpcd_ctx *ctx; struct if_head *ifs; struct interface *ifp, *ifn, *ifl = NULL; const char * const argv[] = { ifname }; int i; ctx = arg; if (action == -1) { ifp = find_interface(ctx, ifname); if (ifp != NULL) { ifp->options->options |= DHCPCD_DEPARTED; stop_interface(ifp); } return; } /* If running off an interface list, check it's in it. */ if (ctx->ifc) { for (i = 0; i < ctx->ifc; i++) if (strcmp(ctx->ifv[i], ifname) == 0) break; if (i >= ctx->ifc) return; } ifs = discover_interfaces(ctx, -1, UNCONST(argv)); TAILQ_FOREACH_SAFE(ifp, ifs, next, ifn) { if (strcmp(ifp->name, ifname) != 0) continue; /* Check if we already have the interface */ ifl = find_interface(ctx, ifp->name); if (ifl) { /* The flags and hwaddr could have changed */ ifl->flags = ifp->flags; ifl->hwlen = ifp->hwlen; if (ifp->hwlen != 0) memcpy(ifl->hwaddr, ifp->hwaddr, ifl->hwlen); } else { TAILQ_REMOVE(ifs, ifp, next); TAILQ_INSERT_TAIL(ctx->ifaces, ifp, next); } if (action == 1) { init_state(ifp, ctx->argc, ctx->argv); start_interface(ifp); } } /* Free our discovered list */ while ((ifp = TAILQ_FIRST(ifs))) { TAILQ_REMOVE(ifs, ifp, next); free_interface(ifp); } free(ifs); } void handle_hwaddr(struct dhcpcd_ctx *ctx, const char *ifname, const uint8_t *hwaddr, uint8_t hwlen) { struct interface *ifp; char buf[sizeof(ifp->hwaddr) * 3]; ifp = find_interface(ctx, ifname); if (ifp == NULL) return; if (hwlen > sizeof(ifp->hwaddr)) { errno = ENOBUFS; syslog(LOG_ERR, "%s: %s: %m", ifp->name, __func__); return; } if (ifp->hwlen == hwlen && memcmp(ifp->hwaddr, hwaddr, hwlen) == 0) return; syslog(LOG_INFO, "%s: new hardware address: %s", ifp->name, hwaddr_ntoa(hwaddr, hwlen, buf, sizeof(buf))); ifp->hwlen = hwlen; memcpy(ifp->hwaddr, hwaddr, hwlen); } static void if_reboot(struct interface *ifp, int argc, char **argv) { unsigned long long oldopts; oldopts = ifp->options->options; script_runreason(ifp, "RECONFIGURE"); configure_interface(ifp, argc, argv); dhcp_reboot_newopts(ifp, oldopts); dhcp6_reboot(ifp); start_interface(ifp); } static void reconf_reboot(struct dhcpcd_ctx *ctx, int action, int argc, char **argv, int oi) { struct if_head *ifs; struct interface *ifn, *ifp; ifs = discover_interfaces(ctx, argc - oi, argv + oi); if (ifs == NULL) return; while ((ifp = TAILQ_FIRST(ifs))) { TAILQ_REMOVE(ifs, ifp, next); ifn = find_interface(ctx, ifp->name); if (ifn) { if (action) if_reboot(ifn, argc, argv); else ipv4_applyaddr(ifn); free_interface(ifp); } else { init_state(ifp, argc, argv); TAILQ_INSERT_TAIL(ctx->ifaces, ifp, next); start_interface(ifp); } } free(ifs); sort_interfaces(ctx); } static void stop_all_interfaces(struct dhcpcd_ctx *ctx, int do_release) { struct interface *ifp; /* drop_dhcp could change the order, so we do it like this. */ for (;;) { /* Be sane and drop the last config first */ ifp = TAILQ_LAST(ctx->ifaces, if_head); if (ifp == NULL) break; if (do_release) { ifp->options->options |= DHCPCD_RELEASE; ifp->options->options &= ~DHCPCD_PERSISTENT; } ifp->options->options |= DHCPCD_EXITING; stop_interface(ifp); } } #ifdef USE_SIGNALS struct dhcpcd_siginfo { int signo; pid_t pid; } dhcpcd_siginfo; #define sigmsg "received signal %s from PID %d, %s" static void handle_signal1(void *arg) { struct dhcpcd_ctx *ctx; struct dhcpcd_siginfo *si; struct interface *ifp; struct if_options *ifo; int do_release; ctx = dhcpcd_ctx; si = arg; do_release = 0; switch (si->signo) { case SIGINT: syslog(LOG_INFO, sigmsg, "INT", (int)si->pid, "stopping"); break; case SIGTERM: syslog(LOG_INFO, sigmsg, "TERM", (int)si->pid, "stopping"); break; case SIGALRM: syslog(LOG_INFO, sigmsg, "ALRM", (int)si->pid, "releasing"); do_release = 1; break; case SIGHUP: syslog(LOG_INFO, sigmsg, "HUP", (int)si->pid, "rebinding"); free_globals(ctx); ifo = read_config(ctx, NULL, NULL, NULL); add_options(ctx, NULL, ifo, ctx->argc, ctx->argv); /* We need to preserve these two options. */ if (ctx->options & DHCPCD_MASTER) ifo->options |= DHCPCD_MASTER; if (ctx->options & DHCPCD_DAEMONISED) ifo->options |= DHCPCD_DAEMONISED; ctx->options = ifo->options; free_options(ifo); /* Preserve any options passed on the commandline * when we were started. */ reconf_reboot(ctx, 1, ctx->argc, ctx->argv, ctx->argc - ctx->ifc); return; case SIGUSR1: syslog(LOG_INFO, sigmsg, "USR1", (int)si->pid, "reconfiguring"); TAILQ_FOREACH(ifp, ctx->ifaces, next) { ipv4_applyaddr(ifp); } return; case SIGPIPE: syslog(LOG_WARNING, "received signal PIPE"); return; default: syslog(LOG_ERR, "received signal %d from PID %d, " "but don't know what to do with it", si->signo, (int)si->pid); return; } if (!(ctx->options & DHCPCD_TEST)) stop_all_interfaces(ctx, do_release); eloop_exit(ctx->eloop, EXIT_FAILURE); } static void handle_signal(int sig, siginfo_t *siginfo, __unused void *context) { /* So that we can operate safely under a signal we instruct * eloop to pass a copy of the siginfo structure to handle_signal1 * as the very first thing to do. */ dhcpcd_siginfo.signo = sig; dhcpcd_siginfo.pid = siginfo ? siginfo->si_pid : 0; eloop_timeout_add_now(dhcpcd_ctx->eloop, handle_signal1, &dhcpcd_siginfo); } static int signal_init(void (*func)(int, siginfo_t *, void *), sigset_t *oldset) { unsigned int i; struct sigaction sa; sigset_t newset; sigfillset(&newset); if (sigprocmask(SIG_SETMASK, &newset, oldset) == -1) return -1; memset(&sa, 0, sizeof(sa)); sa.sa_sigaction = func; sa.sa_flags = SA_SIGINFO; sigemptyset(&sa.sa_mask); for (i = 0; handle_sigs[i]; i++) { if (sigaction(handle_sigs[i], &sa, NULL) == -1) return -1; } return 0; } #endif int handle_args(struct dhcpcd_ctx *ctx, struct fd_list *fd, int argc, char **argv) { struct interface *ifp; int do_exit = 0, do_release = 0, do_reboot = 0; int opt, oi = 0; size_t len, l; struct iovec iov[2]; char *tmp, *p; if (fd != NULL) { /* Special commands for our control socket */ if (strcmp(*argv, "--version") == 0) { len = strlen(VERSION) + 1; iov[0].iov_base = &len; iov[0].iov_len = sizeof(ssize_t); iov[1].iov_base = UNCONST(VERSION); iov[1].iov_len = len; if (writev(fd->fd, iov, 2) == -1) { syslog(LOG_ERR, "writev: %m"); return -1; } return 0; } else if (strcmp(*argv, "--getconfigfile") == 0) { len = strlen(ctx->cffile) + 1; iov[0].iov_base = &len; iov[0].iov_len = sizeof(ssize_t); iov[1].iov_base = UNCONST(ctx->cffile); iov[1].iov_len = len; if (writev(fd->fd, iov, 2) == -1) { syslog(LOG_ERR, "writev: %m"); return -1; } return 0; } else if (strcmp(*argv, "--getinterfaces") == 0) { len = 0; if (argc == 1) { TAILQ_FOREACH(ifp, ctx->ifaces, next) { len++; if (D6_STATE_RUNNING(ifp)) len++; if (ipv6nd_has_ra(ifp)) len++; } if (write(fd->fd, &len, sizeof(len) != sizeof(len))) return -1; TAILQ_FOREACH(ifp, ctx->ifaces, next) { send_interface(fd->fd, ifp); } return 0; } opt = 0; while (argv[++opt] != NULL) { TAILQ_FOREACH(ifp, ctx->ifaces, next) { if (strcmp(argv[opt], ifp->name) == 0) { len++; if (D6_STATE_RUNNING(ifp)) len++; if (ipv6nd_has_ra(ifp)) len++; } } } if (write(fd->fd, &len, sizeof(len)) != sizeof(len)) return -1; opt = 0; while (argv[++opt] != NULL) { TAILQ_FOREACH(ifp, ctx->ifaces, next) { if (strcmp(argv[opt], ifp->name) == 0) send_interface(fd->fd, ifp); } } return 0; } else if (strcmp(*argv, "--listen") == 0) { fd->listener = 1; return 0; } } /* Log the command */ len = 1; for (opt = 0; opt < argc; opt++) len += strlen(argv[opt]) + 1; tmp = malloc(len); if (tmp == NULL) { syslog(LOG_ERR, "%s: %m", __func__); return -1; } p = tmp; for (opt = 0; opt < argc; opt++) { l = strlen(argv[opt]); strlcpy(p, argv[opt], len); len -= l + 1; p += l; *p++ = ' '; } *--p = '\0'; syslog(LOG_INFO, "control command: %s", tmp); free(tmp); optind = 0; while ((opt = getopt_long(argc, argv, IF_OPTS, cf_options, &oi)) != -1) { switch (opt) { case 'g': /* Assumed if below not set */ break; case 'k': do_release = 1; break; case 'n': do_reboot = 1; break; case 'x': do_exit = 1; break; } } if (do_release || do_exit) { if (optind == argc) { stop_all_interfaces(ctx, do_release); eloop_exit(ctx->eloop, EXIT_SUCCESS); return 0; } for (oi = optind; oi < argc; oi++) { if ((ifp = find_interface(ctx, argv[oi])) == NULL) continue; if (do_release) { ifp->options->options |= DHCPCD_RELEASE; ifp->options->options &= ~DHCPCD_PERSISTENT; } ifp->options->options |= DHCPCD_EXITING; stop_interface(ifp); } return 0; } /* XXX: Respect initial commandline options? */ reconf_reboot(ctx, do_reboot, argc, argv, optind); return 0; } int main(int argc, char **argv) { struct dhcpcd_ctx ctx; char pidfile[sizeof(PIDFILE) + IF_NAMESIZE]; struct if_options *ifo; struct interface *ifp; uint16_t family = 0; int opt, oi = 0, i; time_t t; ssize_t len; #if defined(USE_SIGNALS) || !defined(THERE_IS_NO_FORK) pid_t pid; #endif #ifdef USE_SIGNALS int sig; const char *siga; #endif struct timespec ts; memset(&ctx, 0, sizeof(ctx)); #ifdef USE_SIGNALS dhcpcd_ctx = &ctx; sig = 0; siga = NULL; #endif closefrom(3); openlog(PACKAGE, LOG_PERROR | LOG_PID, LOG_DAEMON); setlogmask(LOG_UPTO(LOG_INFO)); /* Test for --help and --version */ if (argc > 1) { if (strcmp(argv[1], "--help") == 0) { usage(); return EXIT_SUCCESS; } else if (strcmp(argv[1], "--version") == 0) { printf(""PACKAGE" "VERSION"\n%s\n", dhcpcd_copyright); return EXIT_SUCCESS; } } ifo = NULL; ctx.cffile = CONFIG; ctx.pid_fd = ctx.control_fd = ctx.link_fd = -1; #ifdef PLUGIN_DEV ctx.dev_fd = -1; #endif #ifdef INET ctx.udp_fd = -1; #endif i = 0; while ((opt = getopt_long(argc, argv, IF_OPTS, cf_options, &oi)) != -1) { switch (opt) { case '4': family = AF_INET; break; case '6': family = AF_INET6; break; case 'f': ctx.cffile = optarg; break; #ifdef USE_SIGNALS case 'g': sig = SIGUSR1; siga = "USR1"; break; case 'k': sig = SIGALRM; siga = "ARLM"; break; case 'n': sig = SIGHUP; siga = "HUP"; break; case 'x': sig = SIGTERM; siga = "TERM";; break; #endif case 'T': i = 1; break; case 'U': i = 2; break; case 'V': i = 3; break; case '?': usage(); goto exit_failure; } } ctx.argv = argv; ctx.argc = argc; ctx.ifc = argc - optind; ctx.ifv = argv + optind; ifo = read_config(&ctx, NULL, NULL, NULL); opt = add_options(&ctx, NULL, ifo, argc, argv); if (opt != 1) { if (opt == 0) usage(); goto exit_failure; } if (i == 3) { printf("Interface options:\n"); if_printoptions(); #ifdef INET if (family == 0 || family == AF_INET) { printf("\nDHCPv4 options:\n"); dhcp_printoptions(&ctx); } #endif #ifdef INET6 if (family == 0 || family == AF_INET6) { printf("\nDHCPv6 options:\n"); dhcp6_printoptions(&ctx); } #endif goto exit_success; } ctx.options = ifo->options; if (i != 0) { if (i == 1) ctx.options |= DHCPCD_TEST; else ctx.options |= DHCPCD_DUMPLEASE; ctx.options |= DHCPCD_PERSISTENT; ctx.options &= ~DHCPCD_DAEMONISE; } #ifdef THERE_IS_NO_FORK ctx.options &= ~DHCPCD_DAEMONISE; #endif if (ctx.options & DHCPCD_DEBUG) setlogmask(LOG_UPTO(LOG_DEBUG)); if (ctx.options & DHCPCD_QUIET) { i = open(_PATH_DEVNULL, O_RDWR); if (i == -1) syslog(LOG_ERR, "%s: open: %m", __func__); else { dup2(i, STDERR_FILENO); close(i); } } if (!(ctx.options & (DHCPCD_TEST | DHCPCD_DUMPLEASE))) { /* If we have any other args, we should run as a single dhcpcd * instance for that interface. */ if (optind == argc - 1 && !(ctx.options & DHCPCD_MASTER)) { if (strlen(argv[optind]) > IF_NAMESIZE) { syslog(LOG_ERR, "%s: interface name too long", argv[optind]); goto exit_failure; } snprintf(pidfile, sizeof(pidfile), PIDFILE, "-", argv[optind]); } else { snprintf(pidfile, sizeof(pidfile), PIDFILE, "", ""); ctx.options |= DHCPCD_MASTER; } } if (chdir("/") == -1) syslog(LOG_ERR, "chdir `/': %m"); if (ctx.options & DHCPCD_DUMPLEASE) { if (optind != argc - 1) { syslog(LOG_ERR, "dumplease requires an interface"); goto exit_failure; } if (dhcp_dump(&ctx, argv[optind]) == -1) goto exit_failure; goto exit_success; } #ifdef USE_SIGNALS if (!(ctx.options & DHCPCD_TEST) && (sig == 0 || ctx.ifc != 0)) { #endif if (ctx.options & DHCPCD_MASTER) i = -1; else i = control_open(&ctx, argv[optind]); if (i == -1) i = control_open(&ctx, NULL); if (i != -1) { syslog(LOG_INFO, "sending commands to master dhcpcd process"); len = control_send(&ctx, argc, argv); control_close(&ctx); if (len > 0) { syslog(LOG_DEBUG, "send OK"); goto exit_success; } else { syslog(LOG_ERR, "failed to send commands"); goto exit_failure; } } else { if (errno != ENOENT) syslog(LOG_ERR, "control_open: %m"); } #ifdef USE_SIGNALS } #endif if (geteuid()) syslog(LOG_WARNING, PACKAGE " will not work correctly unless run as root"); ctx.eloop = eloop_init(); if (ctx.eloop == NULL) { syslog(LOG_ERR, "%s: %m", __func__); goto exit_failure; } #ifdef USE_SIGNALS if (sig != 0) { pid = read_pid(pidfile); if (pid != 0) syslog(LOG_INFO, "sending signal %s to pid %d", siga, pid); if (pid == 0 || kill(pid, sig) != 0) { if (sig != SIGHUP && errno != EPERM) syslog(LOG_ERR, ""PACKAGE" not running"); if (pid != 0 && errno != ESRCH) { syslog(LOG_ERR, "kill: %m"); goto exit_failure; } unlink(pidfile); if (sig != SIGHUP) goto exit_failure; } else { if (sig == SIGHUP || sig == SIGUSR1) goto exit_success; /* Spin until it exits */ syslog(LOG_INFO, "waiting for pid %d to exit", pid); ts.tv_sec = 0; ts.tv_nsec = 100000000; /* 10th of a second */ for(i = 0; i < 100; i++) { nanosleep(&ts, NULL); if (read_pid(pidfile) == 0) goto exit_success; } syslog(LOG_ERR, "pid %d failed to exit", pid); goto exit_failure; } } if (!(ctx.options & DHCPCD_TEST)) { if ((pid = read_pid(pidfile)) > 0 && kill(pid, 0) == 0) { syslog(LOG_ERR, ""PACKAGE " already running on pid %d (%s)", pid, pidfile); goto exit_failure; } /* Ensure we have the needed directories */ if (mkdir(RUNDIR, 0755) == -1 && errno != EEXIST) syslog(LOG_ERR, "mkdir `%s': %m", RUNDIR); if (mkdir(DBDIR, 0755) == -1 && errno != EEXIST) syslog(LOG_ERR, "mkdir `%s': %m", DBDIR); opt = O_WRONLY | O_CREAT | O_NONBLOCK; #ifdef O_CLOEXEC opt |= O_CLOEXEC; #endif ctx.pid_fd = open(pidfile, opt, 0664); if (ctx.pid_fd == -1) syslog(LOG_ERR, "open `%s': %m", pidfile); else { /* Lock the file so that only one instance of dhcpcd * runs on an interface */ if (flock(ctx.pid_fd, LOCK_EX | LOCK_NB) == -1) { syslog(LOG_ERR, "flock `%s': %m", pidfile); close(ctx.pid_fd); ctx.pid_fd = -1; goto exit_failure; } #ifndef O_CLOEXEC if (fcntl(ctx.pid_fd, F_GETFD, &opt) == -1 || fcntl(ctx.pid_fd, F_SETFD, opt | FD_CLOEXEC) == -1) { syslog(LOG_ERR, "fcntl: %m"); close(ctx.pid_fd); ctx.pid_fd = -1; goto exit_failure; } #endif write_pid(ctx.pid_fd, getpid()); } } if (ctx.options & DHCPCD_MASTER) { if (control_start(&ctx, NULL) == -1) syslog(LOG_ERR, "control_start: %m"); } #else if (control_start(&ctx, ctx.options & DHCPCD_MASTER ? NULL : argv[optind]) == -1) { syslog(LOG_ERR, "control_start: %m"); goto exit_failure; } #endif syslog(LOG_INFO, "version " VERSION " starting"); ctx.options |= DHCPCD_STARTED; #ifdef USE_SIGNALS /* Save signal mask, block and redirect signals to our handler */ if (signal_init(handle_signal, &ctx.sigset) == -1) { syslog(LOG_ERR, "signal_setup: %m"); goto exit_failure; } #endif #ifdef __FreeBSD__ syslog(LOG_WARNING, "FreeBSD errors that are worked around:"); syslog(LOG_WARNING, "IPv4 subnet routes cannot be deleted"); #endif /* When running dhcpcd against a single interface, we need to retain * the old behaviour of waiting for an IP address */ if (ctx.ifc == 1 && !(ctx.options & DHCPCD_BACKGROUND)) ctx.options |= DHCPCD_WAITIP; /* RTM_NEWADDR goes through the link socket as well which we * need for IPv6 DAD, so we check for DHCPCD_LINK in handle_carrier * instead. * We also need to open this before checking for interfaces below * so that we pickup any new addresses during the discover phase. */ ctx.link_fd = open_link_socket(); if (ctx.link_fd == -1) syslog(LOG_ERR, "open_link_socket: %m"); else eloop_event_add(ctx.eloop, ctx.link_fd, handle_link, &ctx); /* Start any dev listening plugin which may want to * change the interface name provided by the kernel */ if ((ctx.options & (DHCPCD_MASTER | DHCPCD_DEV)) == (DHCPCD_MASTER | DHCPCD_DEV)) dev_start(&ctx); ctx.ifaces = discover_interfaces(&ctx, ctx.ifc, ctx.ifv); for (i = 0; i < ctx.ifc; i++) { if (find_interface(&ctx, ctx.ifv[i]) == NULL) syslog(LOG_ERR, "%s: interface not found or invalid", ctx.ifv[i]); } if (ctx.ifaces == NULL || TAILQ_FIRST(ctx.ifaces) == NULL) { if (ctx.ifc == 0) syslog(LOG_ERR, "no valid interfaces found"); else goto exit_failure; if (!(ctx.options & DHCPCD_LINK)) { syslog(LOG_ERR, "aborting as link detection is disabled"); goto exit_failure; } } if (ctx.options & DHCPCD_BACKGROUND && daemonise(&ctx)) goto exit_success; opt = 0; TAILQ_FOREACH(ifp, ctx.ifaces, next) { init_state(ifp, argc, argv); if (ifp->carrier != LINK_DOWN) opt = 1; } if (!(ctx.options & DHCPCD_BACKGROUND)) { /* If we don't have a carrier, we may have to wait for a second * before one becomes available if we brought an interface up */ if (opt == 0 && ctx.options & DHCPCD_LINK && ctx.options & DHCPCD_WAITUP && !(ctx.options & DHCPCD_WAITIP)) { ts.tv_sec = 1; ts.tv_nsec = 0; nanosleep(&ts, NULL); TAILQ_FOREACH(ifp, ctx.ifaces, next) { handle_carrier(&ctx, LINK_UNKNOWN, 0, ifp->name); if (ifp->carrier != LINK_DOWN) { opt = 1; break; } } } if (ctx.options & DHCPCD_MASTER) t = ifo->timeout; else if ((ifp = TAILQ_FIRST(ctx.ifaces))) t = ifp->options->timeout; else t = 0; if (opt == 0 && ctx.options & DHCPCD_LINK && !(ctx.options & DHCPCD_WAITIP)) { syslog(LOG_WARNING, "no interfaces have a carrier"); if (daemonise(&ctx)) goto exit_success; } else if (t > 0) { if (ctx.options & DHCPCD_IPV4LL) ctx.options |= DHCPCD_TIMEOUT_IPV4LL; eloop_timeout_add_sec(ctx.eloop, t, handle_exit_timeout, &ctx); } } free_options(ifo); ifo = NULL; sort_interfaces(&ctx); TAILQ_FOREACH(ifp, ctx.ifaces, next) { eloop_timeout_add_sec(ctx.eloop, 0, start_interface, ifp); } i = eloop_start(&ctx); goto exit1; exit_success: i = EXIT_SUCCESS; goto exit1; exit_failure: i = EXIT_FAILURE; exit1: /* Free memory and close fd's */ if (ctx.ifaces) { while ((ifp = TAILQ_FIRST(ctx.ifaces))) { TAILQ_REMOVE(ctx.ifaces, ifp, next); free_interface(ifp); } free(ctx.ifaces); } free(ctx.duid); if (ctx.link_fd != -1) { eloop_event_delete(ctx.eloop, ctx.link_fd); close(ctx.link_fd); } free_options(ifo); free_globals(&ctx); restore_kernel_ra(&ctx); ipv4_ctxfree(&ctx); ipv6_ctxfree(&ctx); dev_stop(&ctx, !(ctx.options & DHCPCD_FORKED)); if (!(ctx.options & DHCPCD_FORKED) && control_stop(&ctx) == -1) syslog(LOG_ERR, "control_stop: %m:"); if (ctx.pid_fd != -1) { close(ctx.pid_fd); unlink(pidfile); } eloop_free(ctx.eloop); if (ctx.options & DHCPCD_STARTED && !(ctx.options & DHCPCD_FORKED)) syslog(LOG_INFO, "exited"); closelog(); return i; }