/* * dhcpcd - DHCP client daemon * Copyright (c) 2006-2010 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 copyright[] = "Copyright (c) 2006-2010 Roy Marples"; #include #include #include #include #include #include #include #include #ifdef __linux__ # include /* for systems with broken headers */ # include #endif #include #include #include #include #include #include #include #include #include #include #include #include #include "arp.h" #include "bind.h" #include "config.h" #include "common.h" #include "configure.h" #include "control.h" #include "dhcpcd.h" #include "duid.h" #include "eloop.h" #include "if-options.h" #include "if-pref.h" #include "ipv4ll.h" #include "net.h" #include "signals.h" #ifdef ANDROID #include #include #include #include #endif /* We should define a maximum for the NAK exponential backoff */ #define NAKOFF_MAX 60 /* Wait N nanoseconds between sending a RELEASE and dropping the address. * This gives the kernel enough time to actually send it. */ #define RELEASE_DELAY_S 0 #define RELEASE_DELAY_NS 10000000 int options = 0; int pidfd = -1; struct interface *ifaces = NULL; int ifac = 0; char **ifav = NULL; int ifdc = 0; char **ifdv = NULL; static char **margv; static int margc; static struct if_options *if_options; static char **ifv; static int ifc; static char *cffile; static char *pidfile; static int linkfd = -1; struct dhcp_op { uint8_t value; const char *name; }; static const struct dhcp_op dhcp_ops[] = { { DHCP_DISCOVER, "DISCOVER" }, { DHCP_OFFER, "OFFER" }, { DHCP_REQUEST, "REQUEST" }, { DHCP_DECLINE, "DECLINE" }, { DHCP_ACK, "ACK" }, { DHCP_NAK, "NAK" }, { DHCP_RELEASE, "RELEASE" }, { DHCP_INFORM, "INFORM" }, { 0, NULL } }; static void send_release(struct interface *); static const char * get_dhcp_op(uint8_t type) { const struct dhcp_op *d; for (d = dhcp_ops; d->name; d++) if (d->value == type) return d->name; return NULL; } static pid_t read_pid(void) { 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 void usage(void) { printf("usage: "PACKAGE" [-dgknpqwxyADEGHJKLOTV] [-c script] [-f file]" " [-e var=val]\n" " [-h hostname] [-i classID ] [-l leasetime]" " [-m metric] [-o option]\n" " [-r ipaddr] [-s ipaddr] [-t timeout]" " [-u userclass]\n" " [-F none|ptr|both] [-I clientID] [-C hookscript]" " [-Q option]\n" " [-X ipaddr] \n"); } static void cleanup(void) { #ifdef DEBUG_MEMORY struct interface *iface; int i; free_options(if_options); while (ifaces) { iface = ifaces; ifaces = iface->next; free_interface(iface); } for (i = 0; i < ifac; i++) free(ifav[i]); free(ifav); for (i = 0; i < ifdc; i++) free(ifdv[i]); free(ifdv); #endif if (linkfd != -1) close(linkfd); if (pidfd > -1) { if (options & DHCPCD_MASTER) { if (stop_control() == -1) syslog(LOG_ERR, "stop_control: %m"); } close(pidfd); unlink(pidfile); } #ifdef DEBUG_MEMORY free(pidfile); #endif } /* ARGSUSED */ void handle_exit_timeout(_unused void *arg) { int timeout; syslog(LOG_ERR, "timed out"); if (!(options & DHCPCD_TIMEOUT_IPV4LL)) { if (options & DHCPCD_MASTER) { daemonise(); return; } else exit(EXIT_FAILURE); } options &= ~DHCPCD_TIMEOUT_IPV4LL; timeout = (PROBE_NUM * PROBE_MAX) + PROBE_WAIT + 1; syslog(LOG_WARNING, "allowing %d seconds for IPv4LL timeout", timeout); add_timeout_sec(timeout, handle_exit_timeout, NULL); } void drop_config(struct interface *iface, const char *reason) { free(iface->state->old); iface->state->old = iface->state->new; iface->state->new = NULL; iface->state->reason = reason; configure(iface); free(iface->state->old); iface->state->old = NULL; iface->state->lease.addr.s_addr = 0; } struct interface * find_interface(const char *ifname) { struct interface *ifp; for (ifp = ifaces; ifp; ifp = ifp->next) if (strcmp(ifp->name, ifname) == 0) return ifp; return NULL; } static void stop_interface(struct interface *iface) { struct interface *ifp, *ifl = NULL; syslog(LOG_INFO, "%s: removing interface", iface->name); if (strcmp(iface->state->reason, "RELEASE") != 0) drop_config(iface, "STOP"); close_sockets(iface); delete_timeout(NULL, iface); for (ifp = ifaces; ifp; ifp = ifp->next) { if (ifp == iface) break; ifl = ifp; } if (ifl) ifl->next = ifp->next; else ifaces = ifp->next; free_interface(ifp); if (!(options & (DHCPCD_MASTER | DHCPCD_TEST))) exit(EXIT_FAILURE); } static uint32_t dhcp_xid(struct interface *iface) { uint32_t xid; if (iface->state->options->options & DHCPCD_XID_HWADDR && iface->hwlen >= sizeof(xid)) /* The lower bits are probably more unique on the network */ memcpy(&xid, (iface->hwaddr + iface->hwlen) - sizeof(xid), sizeof(xid)); else xid = arc4random(); return xid; } static void send_message(struct interface *iface, int type, void (*callback)(void *)) { struct if_state *state = iface->state; struct if_options *ifo = state->options; struct dhcp_message *dhcp; uint8_t *udp; ssize_t len, r; struct in_addr from, to; in_addr_t a = 0; struct timeval tv; if (!callback) syslog(LOG_DEBUG, "%s: sending %s with xid 0x%x", iface->name, get_dhcp_op(type), state->xid); else { if (state->interval == 0) state->interval = 4; else { state->interval *= 2; if (state->interval > 64) state->interval = 64; } tv.tv_sec = state->interval + DHCP_RAND_MIN; tv.tv_usec = arc4random() % (DHCP_RAND_MAX_U - DHCP_RAND_MIN_U); syslog(LOG_DEBUG, "%s: sending %s (xid 0x%x), next in %0.2f seconds", iface->name, get_dhcp_op(type), state->xid, timeval_to_double(&tv)); } /* Ensure sockets are open. */ open_sockets(iface); /* If we couldn't open a UDP port for our IP address * then we cannot renew. * This could happen if our IP was pulled out from underneath us. * Also, we should not unicast from a BOOTP lease. */ if (iface->udp_fd == -1 || (!(ifo->options & DHCPCD_INFORM) && is_bootp(iface->state->new))) { a = iface->addr.s_addr; iface->addr.s_addr = 0; } len = make_message(&dhcp, iface, type); if (a) iface->addr.s_addr = a; from.s_addr = dhcp->ciaddr; if (from.s_addr) to.s_addr = state->lease.server.s_addr; else to.s_addr = 0; if (to.s_addr && to.s_addr != INADDR_BROADCAST) { r = send_packet(iface, to, (uint8_t *)dhcp, len); if (r == -1) { syslog(LOG_ERR, "%s: send_packet: %m", iface->name); close_sockets(iface); } } else { len = make_udp_packet(&udp, (uint8_t *)dhcp, len, from, to); r = send_raw_packet(iface, ETHERTYPE_IP, udp, len); free(udp); /* If we failed to send a raw packet this normally means * we don't have the ability to work beneath the IP layer * for this interface. * As such we remove it from consideration without actually * stopping the interface. */ if (r == -1) { syslog(LOG_ERR, "%s: send_raw_packet: %m", iface->name); if (!(options & DHCPCD_TEST)) drop_config(iface, "FAIL"); close_sockets(iface); delete_timeout(NULL, iface); callback = NULL; } } free(dhcp); /* Even if we fail to send a packet we should continue as we are * as our failure timeouts will change out codepath when needed. */ if (callback) add_timeout_tv(&tv, callback, iface); } static void send_inform(void *arg) { send_message((struct interface *)arg, DHCP_INFORM, send_inform); } static void send_discover(void *arg) { send_message((struct interface *)arg, DHCP_DISCOVER, send_discover); } static void send_request(void *arg) { send_message((struct interface *)arg, DHCP_REQUEST, send_request); } static void send_renew(void *arg) { send_message((struct interface *)arg, DHCP_REQUEST, send_renew); } static void send_rebind(void *arg) { send_message((struct interface *)arg, DHCP_REQUEST, send_rebind); } void start_expire(void *arg) { struct interface *iface = arg; iface->state->interval = 0; if (iface->addr.s_addr == 0) { /* We failed to reboot, so enter discovery. */ iface->state->lease.addr.s_addr = 0; start_discover(iface); return; } syslog(LOG_ERR, "%s: lease expired", iface->name); delete_timeout(NULL, iface); drop_config(iface, "EXPIRE"); unlink(iface->leasefile); if (iface->carrier != LINK_DOWN) start_interface(iface); } static void log_dhcp(int lvl, const char *msg, const struct interface *iface, const struct dhcp_message *dhcp, const struct in_addr *from) { const char *tfrom; char *a; struct in_addr addr; int r; if (strcmp(msg, "NAK:") == 0) a = get_option_string(dhcp, DHO_MESSAGE); else if (dhcp->yiaddr != 0) { addr.s_addr = dhcp->yiaddr; a = xstrdup(inet_ntoa(addr)); } else a = NULL; tfrom = "from"; r = get_option_addr(&addr, dhcp, DHO_SERVERID); if (dhcp->servername[0] && r == 0) syslog(lvl, "%s: %s %s %s %s `%s'", iface->name, msg, a, tfrom, inet_ntoa(addr), dhcp->servername); else { if (r != 0) { tfrom = "via"; addr = *from; } if (a == NULL) syslog(lvl, "%s: %s %s %s", iface->name, msg, tfrom, inet_ntoa(addr)); else syslog(lvl, "%s: %s %s %s %s", iface->name, msg, a, tfrom, inet_ntoa(addr)); } free(a); } static int blacklisted_ip(const struct if_options *ifo, in_addr_t addr) { size_t i; for (i = 0; i < ifo->blacklist_len; i += 2) if (ifo->blacklist[i] == (addr & ifo->blacklist[i + 1])) return 1; return 0; } static int whitelisted_ip(const struct if_options *ifo, in_addr_t addr) { size_t i; if (ifo->whitelist_len == 0) return -1; for (i = 0; i < ifo->whitelist_len; i += 2) if (ifo->whitelist[i] == (addr & ifo->whitelist[i + 1])) return 1; return 0; } static void handle_dhcp(struct interface *iface, struct dhcp_message **dhcpp, const struct in_addr *from) { struct if_state *state = iface->state; struct if_options *ifo = state->options; struct dhcp_message *dhcp = *dhcpp; struct dhcp_lease *lease = &state->lease; uint8_t type, tmp; struct in_addr addr; size_t i; /* reset the message counter */ state->interval = 0; /* We may have found a BOOTP server */ if (get_option_uint8(&type, dhcp, DHO_MESSAGETYPE) == -1) type = 0; if (type == DHCP_NAK) { /* For NAK, only check if we require the ServerID */ if (has_option_mask(ifo->requiremask, DHO_SERVERID) && get_option_addr(&addr, dhcp, DHO_SERVERID) == -1) { log_dhcp(LOG_WARNING, "reject NAK", iface, dhcp, from); return; } /* We should restart on a NAK */ log_dhcp(LOG_WARNING, "NAK:", iface, dhcp, from); if (!(options & DHCPCD_TEST)) { drop_config(iface, "NAK"); unlink(iface->leasefile); } close_sockets(iface); /* If we constantly get NAKS then we should slowly back off */ add_timeout_sec(state->nakoff, start_interface, iface); state->nakoff *= 2; if (state->nakoff > NAKOFF_MAX) state->nakoff = NAKOFF_MAX; return; } /* Ensure that all required options are present */ for (i = 1; i < 255; i++) { if (has_option_mask(ifo->requiremask, i) && get_option_uint8(&tmp, dhcp, i) != 0) { /* If we are bootp, then ignore the need for serverid. * To ignore bootp, require dhcp_message_type instead. */ if (type == 0 && i == DHO_SERVERID) continue; log_dhcp(LOG_WARNING, "reject DHCP", iface, dhcp, from); return; } } /* No NAK, so reset the backoff */ state->nakoff = 1; if ((type == 0 || type == DHCP_OFFER) && state->state == DHS_DISCOVER) { lease->frominfo = 0; lease->addr.s_addr = dhcp->yiaddr; lease->cookie = dhcp->cookie; if (type == 0 || get_option_addr(&lease->server, dhcp, DHO_SERVERID) != 0) lease->server.s_addr = INADDR_ANY; log_dhcp(LOG_INFO, "offered", iface, dhcp, from); free(state->offer); state->offer = dhcp; *dhcpp = NULL; if (options & DHCPCD_TEST) { free(state->old); state->old = state->new; state->new = state->offer; state->offer = NULL; state->reason = "TEST"; run_script(iface); exit(EXIT_SUCCESS); } delete_timeout(send_discover, iface); /* We don't request BOOTP addresses */ if (type) { /* We used to ARP check here, but that seems to be in * violation of RFC2131 where it only describes * DECLINE after REQUEST. * It also seems that some MS DHCP servers actually * ignore DECLINE if no REQUEST, ie we decline a * DISCOVER. */ start_request(iface); return; } } if (type) { if (type == DHCP_OFFER) { log_dhcp(LOG_INFO, "ignoring offer of", iface, dhcp, from); return; } /* We should only be dealing with acks */ if (type != DHCP_ACK) { log_dhcp(LOG_ERR, "not ACK or OFFER", iface, dhcp, from); return; } if (!(ifo->options & DHCPCD_INFORM)) log_dhcp(LOG_INFO, "acknowledged", iface, dhcp, from); } /* BOOTP could have already assigned this above, so check we still * have a pointer. */ if (*dhcpp) { free(state->offer); state->offer = dhcp; *dhcpp = NULL; } lease->frominfo = 0; delete_timeout(NULL, iface); /* We now have an offer, so close the DHCP sockets. * This allows us to safely ARP when broken DHCP servers send an ACK * follows by an invalid NAK. */ close_sockets(iface); if (ifo->options & DHCPCD_ARP && iface->addr.s_addr != state->offer->yiaddr) { /* If the interface already has the address configured * then we can't ARP for duplicate detection. */ addr.s_addr = state->offer->yiaddr; if (has_address(iface->name, &addr, NULL) != 1) { state->claims = 0; state->probes = 0; state->conflicts = 0; state->state = DHS_PROBE; send_arp_probe(iface); return; } } bind_interface(iface); } static void handle_dhcp_packet(void *arg) { struct interface *iface = arg; uint8_t *packet; struct dhcp_message *dhcp = NULL; const uint8_t *pp; ssize_t bytes; struct in_addr from; int i; /* We loop through until our buffer is empty. * The benefit is that if we get >1 DHCP packet in our buffer and * the first one fails for any reason, we can use the next. */ packet = xmalloc(udp_dhcp_len); for(;;) { bytes = get_raw_packet(iface, ETHERTYPE_IP, packet, udp_dhcp_len); if (bytes == 0 || bytes == -1) break; if (valid_udp_packet(packet, bytes, &from) == -1) { syslog(LOG_ERR, "%s: invalid UDP packet from %s", iface->name, inet_ntoa(from)); continue; } i = whitelisted_ip(iface->state->options, from.s_addr); if (i == 0) { syslog(LOG_WARNING, "%s: non whitelisted DHCP packet from %s", iface->name, inet_ntoa(from)); continue; } else if (i != 1 && blacklisted_ip(iface->state->options, from.s_addr) == 1) { syslog(LOG_WARNING, "%s: blacklisted DHCP packet from %s", iface->name, inet_ntoa(from)); continue; } if (iface->flags & IFF_POINTOPOINT && iface->dst.s_addr != from.s_addr) { syslog(LOG_WARNING, "%s: server %s is not destination", iface->name, inet_ntoa(from)); } bytes = get_udp_data(&pp, packet); if ((size_t)bytes > sizeof(*dhcp)) { syslog(LOG_ERR, "%s: packet greater than DHCP size from %s", iface->name, inet_ntoa(from)); continue; } if (!dhcp) dhcp = xzalloc(sizeof(*dhcp)); memcpy(dhcp, pp, bytes); if (dhcp->cookie != htonl(MAGIC_COOKIE)) { syslog(LOG_DEBUG, "%s: bogus cookie from %s", iface->name, inet_ntoa(from)); continue; } /* Ensure it's the right transaction */ if (iface->state->xid != dhcp->xid) { syslog(LOG_DEBUG, "%s: wrong xid 0x%x (expecting 0x%x) from %s", iface->name, dhcp->xid, iface->state->xid, inet_ntoa(from)); continue; } /* Ensure packet is for us */ if (iface->hwlen <= sizeof(dhcp->chaddr) && memcmp(dhcp->chaddr, iface->hwaddr, iface->hwlen)) { syslog(LOG_DEBUG, "%s: xid 0x%x is not for hwaddr %s", iface->name, dhcp->xid, hwaddr_ntoa(dhcp->chaddr, sizeof(dhcp->chaddr))); continue; } handle_dhcp(iface, &dhcp, &from); if (iface->raw_fd == -1) break; } free(packet); free(dhcp); } static void send_release(struct interface *iface) { struct timespec ts; if (iface->state->new != NULL && iface->state->new->cookie == htonl(MAGIC_COOKIE)) { syslog(LOG_INFO, "%s: releasing lease of %s", iface->name, inet_ntoa(iface->state->lease.addr)); iface->state->xid = dhcp_xid(iface); send_message(iface, DHCP_RELEASE, NULL); /* Give the packet a chance to go before dropping the ip */ ts.tv_sec = RELEASE_DELAY_S; ts.tv_nsec = RELEASE_DELAY_NS; nanosleep(&ts, NULL); drop_config(iface, "RELEASE"); } unlink(iface->leasefile); } void send_decline(struct interface *iface) { send_message(iface, DHCP_DECLINE, NULL); } static void configure_interface1(struct interface *iface) { struct if_state *ifs = iface->state; struct if_options *ifo = ifs->options; uint8_t *duid; size_t len = 0, ifl; /* Do any platform specific configuration */ if_conf(iface); if (iface->flags & IFF_POINTOPOINT && !(ifo->options & DHCPCD_INFORM)) ifo->options |= DHCPCD_STATIC; if (iface->flags & IFF_NOARP || ifo->options & (DHCPCD_INFORM | DHCPCD_STATIC)) ifo->options &= ~(DHCPCD_ARP | DHCPCD_IPV4LL); if (ifo->options & DHCPCD_LINK && carrier_status(iface) == -1) ifo->options &= ~DHCPCD_LINK; if (ifo->metric != -1) iface->metric = ifo->metric; /* 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 (iface->hwlen > DHCP_CHADDR_LEN) ifo->options |= DHCPCD_CLIENTID; /* Firewire and InfiniBand interfaces require ClientID and * the broadcast option being set. */ switch (iface->family) { case ARPHRD_IEEE1394: /* FALLTHROUGH */ case ARPHRD_INFINIBAND: ifo->options |= DHCPCD_CLIENTID | DHCPCD_BROADCAST; break; } free(iface->clientid); iface->clientid = NULL; if (*ifo->clientid) { iface->clientid = xmalloc(ifo->clientid[0] + 1); memcpy(iface->clientid, ifo->clientid, ifo->clientid[0] + 1); } else if (ifo->options & DHCPCD_CLIENTID) { if (ifo->options & DHCPCD_DUID) { duid = xmalloc(DUID_LEN); if ((len = get_duid(duid, iface)) == 0) syslog(LOG_ERR, "get_duid: %m"); } if (len > 0) { iface->clientid = xmalloc(len + 6); iface->clientid[0] = len + 5; iface->clientid[1] = 255; /* RFC 4361 */ ifl = strlen(iface->name); if (ifl < 5) { memcpy(iface->clientid + 2, iface->name, ifl); if (ifl < 4) memset(iface->clientid + 2 + ifl, 0, 4 - ifl); } else { ifl = htonl(if_nametoindex(iface->name)); memcpy(iface->clientid + 2, &ifl, 4); } } else if (len == 0) { len = iface->hwlen + 1; iface->clientid = xmalloc(len + 1); iface->clientid[0] = len; iface->clientid[1] = iface->family; memcpy(iface->clientid + 2, iface->hwaddr, iface->hwlen); } } if (ifo->options & DHCPCD_CLIENTID) syslog(LOG_DEBUG, "%s: using ClientID %s", iface->name, hwaddr_ntoa(iface->clientid + 1, *iface->clientid)); else syslog(LOG_DEBUG, "%s: using hwaddr %s", iface->name, hwaddr_ntoa(iface->hwaddr, iface->hwlen)); } int select_profile(struct interface *iface, const char *profile) { struct if_options *ifo; int ret; ret = 0; ifo = read_config(cffile, iface->name, iface->ssid, profile); if (ifo == NULL) { syslog(LOG_DEBUG, "%s: no profile %s", iface->name, profile); ret = -1; goto exit; } if (profile != NULL) { strlcpy(iface->state->profile, profile, sizeof(iface->state->profile)); syslog(LOG_INFO, "%s: selected profile %s", iface->name, profile); } else *iface->state->profile = '\0'; free_options(iface->state->options); iface->state->options = ifo; exit: if (profile) configure_interface1(iface); return ret; } static void start_fallback(void *arg) { struct interface *iface; iface = (struct interface *)arg; select_profile(iface, iface->state->options->fallback); start_interface(iface); } static void configure_interface(struct interface *iface, int argc, char **argv) { select_profile(iface, NULL); add_options(iface->state->options, argc, argv); configure_interface1(iface); } static void handle_carrier(const char *ifname) { struct interface *iface; int carrier; if (!(options & DHCPCD_LINK)) return; for (iface = ifaces; iface; iface = iface->next) if (strcmp(iface->name, ifname) == 0) break; if (!iface || !(iface->state->options->options & DHCPCD_LINK)) return; carrier = carrier_status(iface); if (carrier == -1) syslog(LOG_ERR, "%s: carrier_status: %m", ifname); else if (carrier == 0 || !(iface->flags & IFF_RUNNING)) { if (iface->carrier != LINK_DOWN) { iface->carrier = LINK_DOWN; syslog(LOG_INFO, "%s: carrier lost", iface->name); close_sockets(iface); delete_timeouts(iface, start_expire, NULL); drop_config(iface, "NOCARRIER"); } } else if (carrier == 1 && (iface->flags & IFF_RUNNING)) { if (iface->carrier != LINK_UP) { iface->carrier = LINK_UP; syslog(LOG_INFO, "%s: carrier acquired", iface->name); if (iface->wireless) getifssid(iface->name, iface->ssid); configure_interface(iface, margc, margv); iface->state->interval = 0; iface->state->reason = "CARRIER"; run_script(iface); start_interface(iface); } } } void start_discover(void *arg) { struct interface *iface = arg; struct if_options *ifo = iface->state->options; iface->state->state = DHS_DISCOVER; iface->state->xid = dhcp_xid(iface); delete_timeout(NULL, iface); if (ifo->fallback) add_timeout_sec(ifo->timeout, start_fallback, iface); else if (ifo->options & DHCPCD_IPV4LL && !IN_LINKLOCAL(htonl(iface->addr.s_addr))) { if (IN_LINKLOCAL(htonl(iface->state->fail.s_addr))) add_timeout_sec(RATE_LIMIT_INTERVAL, start_ipv4ll, iface); else add_timeout_sec(ifo->timeout, start_ipv4ll, iface); } syslog(LOG_INFO, "%s: broadcasting for a lease", iface->name); send_discover(iface); } void start_request(void *arg) { struct interface *iface = arg; iface->state->state = DHS_REQUEST; send_request(iface); } void start_renew(void *arg) { struct interface *iface = arg; syslog(LOG_INFO, "%s: renewing lease of %s", iface->name, inet_ntoa(iface->state->lease.addr)); iface->state->state = DHS_RENEW; iface->state->xid = dhcp_xid(iface); send_renew(iface); } void start_rebind(void *arg) { struct interface *iface = arg; syslog(LOG_ERR, "%s: failed to renew, attempting to rebind", iface->name); iface->state->state = DHS_REBIND; delete_timeout(send_renew, iface); iface->state->lease.server.s_addr = 0; send_rebind(iface); } static void start_timeout(void *arg) { struct interface *iface = arg; bind_interface(iface); iface->state->interval = 0; start_discover(iface); } static struct dhcp_message * dhcp_message_new(struct in_addr *addr, struct in_addr *mask) { struct dhcp_message *dhcp; uint8_t *p; dhcp = xzalloc(sizeof(*dhcp)); dhcp->yiaddr = addr->s_addr; p = dhcp->options; if (mask && mask->s_addr != INADDR_ANY) { *p++ = DHO_SUBNETMASK; *p++ = sizeof(mask->s_addr); memcpy(p, &mask->s_addr, sizeof(mask->s_addr)); p+= sizeof(mask->s_addr); } *p++ = DHO_END; return dhcp; } static int handle_3rdparty(struct interface *iface) { struct if_options *ifo; struct in_addr addr, net, dst; ifo = iface->state->options; if (ifo->req_addr.s_addr != INADDR_ANY) return 0; if (get_address(iface->name, &addr, &net, &dst) == 1) handle_ifa(RTM_NEWADDR, iface->name, &addr, &net, &dst); else { syslog(LOG_INFO, "%s: waiting for 3rd party to configure IP address", iface->name); iface->state->reason = "3RDPARTY"; run_script(iface); } return 1; } static void start_static(struct interface *iface) { struct if_options *ifo; if (handle_3rdparty(iface)) return; ifo = iface->state->options; iface->state->offer = dhcp_message_new(&ifo->req_addr, &ifo->req_mask); delete_timeout(NULL, iface); bind_interface(iface); } static void start_inform(struct interface *iface) { if (handle_3rdparty(iface)) return; if (options & DHCPCD_TEST) { iface->addr.s_addr = iface->state->options->req_addr.s_addr; iface->net.s_addr = iface->state->options->req_mask.s_addr; } else { iface->state->options->options |= DHCPCD_STATIC; start_static(iface); } iface->state->state = DHS_INFORM; iface->state->xid = dhcp_xid(iface); send_inform(iface); } void start_reboot(struct interface *iface) { struct if_options *ifo = iface->state->options; if (ifo->options & DHCPCD_LINK && iface->carrier == LINK_DOWN) { syslog(LOG_INFO, "%s: waiting for carrier", iface->name); return; } if (ifo->options & DHCPCD_STATIC) { start_static(iface); return; } if (ifo->reboot == 0 || iface->state->offer == NULL) { start_discover(iface); return; } if (ifo->options & DHCPCD_INFORM) { syslog(LOG_INFO, "%s: informing address of %s", iface->name, inet_ntoa(iface->state->lease.addr)); } else if (iface->state->offer->cookie == 0) { if (ifo->options & DHCPCD_IPV4LL) { iface->state->claims = 0; send_arp_announce(iface); } else start_discover(iface); return; } else { syslog(LOG_INFO, "%s: rebinding lease of %s", iface->name, inet_ntoa(iface->state->lease.addr)); } iface->state->state = DHS_REBOOT; iface->state->xid = dhcp_xid(iface); iface->state->lease.server.s_addr = 0; delete_timeout(NULL, iface); if (ifo->fallback) add_timeout_sec(ifo->reboot, start_fallback, iface); else if (ifo->options & DHCPCD_LASTLEASE && iface->state->lease.frominfo) add_timeout_sec(ifo->reboot, start_timeout, iface); else if (!(ifo->options & DHCPCD_INFORM && options & (DHCPCD_MASTER | DHCPCD_DAEMONISED))) add_timeout_sec(ifo->reboot, start_expire, iface); /* Don't bother ARP checking as the server could NAK us first. */ if (ifo->options & DHCPCD_INFORM) send_inform(iface); else send_request(iface); } void start_interface(void *arg) { struct interface *iface = arg; struct if_options *ifo = iface->state->options; struct stat st; struct timeval now; uint32_t l; int nolease; handle_carrier(iface->name); if (iface->carrier == LINK_DOWN) { syslog(LOG_INFO, "%s: waiting for carrier", iface->name); return; } iface->start_uptime = uptime(); free(iface->state->offer); iface->state->offer = NULL; if (iface->state->arping_index < ifo->arping_len) { start_arping(iface); return; } if (ifo->options & DHCPCD_STATIC) { start_static(iface); return; } if (ifo->options & DHCPCD_INFORM) { start_inform(iface); return; } if (iface->hwlen == 0 && ifo->clientid[0] == '\0') { syslog(LOG_WARNING, "%s: needs a clientid to configure", iface->name); drop_config(iface, "FAIL"); close_sockets(iface); delete_timeout(NULL, iface); return; } /* We don't want to read the old lease if we NAK an old test */ nolease = iface->state->offer && options & DHCPCD_TEST; if (!nolease) iface->state->offer = read_lease(iface); if (iface->state->offer) { get_lease(&iface->state->lease, iface->state->offer); iface->state->lease.frominfo = 1; if (iface->state->offer->cookie == 0) { if (iface->state->offer->yiaddr == iface->addr.s_addr) { free(iface->state->offer); iface->state->offer = NULL; } } else if (iface->state->lease.leasetime != ~0U && stat(iface->leasefile, &st) == 0) { /* Offset lease times and check expiry */ gettimeofday(&now, NULL); if ((time_t)iface->state->lease.leasetime < (time_t)(now.tv_sec - st.st_mtime)) { syslog(LOG_DEBUG, "%s: discarding expired lease", iface->name); free(iface->state->offer); iface->state->offer = NULL; iface->state->lease.addr.s_addr = 0; } else { l = now.tv_sec - st.st_mtime; iface->state->lease.leasetime -= l; iface->state->lease.renewaltime -= l; iface->state->lease.rebindtime -= l; } } } if (iface->state->offer == NULL) start_discover(iface); else if (iface->state->offer->cookie == 0 && iface->state->options->options & DHCPCD_IPV4LL) start_ipv4ll(iface); else start_reboot(iface); } static void init_state(struct interface *iface, int argc, char **argv) { struct if_state *ifs; if (iface->state) ifs = iface->state; else ifs = iface->state = xzalloc(sizeof(*ifs)); ifs->state = DHS_INIT; ifs->reason = "PREINIT"; ifs->nakoff = 1; configure_interface(iface, argc, argv); if (!(options & DHCPCD_TEST)) run_script(iface); /* We need to drop the leasefile so that start_interface * doesn't load it. */ if (ifs->options->options & DHCPCD_REQUEST) unlink(iface->leasefile); if (ifs->options->options & DHCPCD_LINK) { switch (carrier_status(iface)) { case 0: iface->carrier = LINK_DOWN; ifs->reason = "NOCARRIER"; break; case 1: iface->carrier = LINK_UP; ifs->reason = "CARRIER"; break; default: iface->carrier = LINK_UNKNOWN; return; } if (!(options & DHCPCD_TEST)) run_script(iface); } else iface->carrier = LINK_UNKNOWN; } void handle_interface(int action, const char *ifname) { struct interface *ifs, *ifp, *ifn, *ifl = NULL; const char * const argv[] = { ifname }; int i; if (action == -1) { ifp = find_interface(ifname); if (ifp != NULL) stop_interface(ifp); return; } else if (action == 0) { handle_carrier(ifname); return; } /* If running off an interface list, check it's in it. */ if (ifc) { for (i = 0; i < ifc; i++) if (strcmp(ifv[i], ifname) == 0) break; if (i >= ifc) return; } ifs = discover_interfaces(-1, UNCONST(argv)); for (ifp = ifs; ifp; ifp = ifp->next) { if (strcmp(ifp->name, ifname) != 0) continue; /* Check if we already have the interface */ for (ifn = ifaces; ifn; ifn = ifn->next) { if (strcmp(ifn->name, ifp->name) == 0) break; ifl = ifn; } if (ifn) { /* The flags and hwaddr could have changed */ ifn->flags = ifp->flags; ifn->hwlen = ifp->hwlen; if (ifp->hwlen != 0) memcpy(ifn->hwaddr, ifp->hwaddr, ifn->hwlen); } else { if (ifl) ifl->next = ifp; else ifaces = ifp; } init_state(ifp, 0, NULL); start_interface(ifp); } } #ifdef RTM_CHGADDR void handle_hwaddr(const char *ifname, unsigned char *hwaddr, size_t hwlen) { struct interface *ifp; struct if_options *ifo; for (ifp = ifaces; ifp; ifp = ifp->next) if (strcmp(ifp->name, ifname) == 0 && ifp->hwlen <= hwlen) { ifo = ifp->state->options; if (!(ifo->options & (DHCPCD_INFORM | DHCPCD_STATIC | DHCPCD_CLIENTID)) && ifp->state->new != NULL && ifp->state->new->cookie == htonl(MAGIC_COOKIE)) { syslog(LOG_INFO, "%s: expiring for new hardware address", ifp->name); drop_config(ifp, "EXPIRE"); } memcpy(ifp->hwaddr, hwaddr, hwlen); ifp->hwlen = hwlen; if (!(ifo->options & (DHCPCD_INFORM | DHCPCD_STATIC | DHCPCD_CLIENTID))) { syslog(LOG_DEBUG, "%s: using hwaddr %s", ifp->name, hwaddr_ntoa(ifp->hwaddr, ifp->hwlen)); ifp->state->interval = 0; ifp->state->nakoff = 1; start_interface(ifp); } } free(hwaddr); } #endif void handle_ifa(int type, const char *ifname, struct in_addr *addr, struct in_addr *net, struct in_addr *dst) { struct interface *ifp; struct if_options *ifo; int i; if (addr->s_addr == INADDR_ANY) return; for (ifp = ifaces; ifp; ifp = ifp->next) if (strcmp(ifp->name, ifname) == 0) break; if (ifp == NULL) return; ifo = ifp->state->options; if ((ifo->options & (DHCPCD_INFORM | DHCPCD_STATIC)) == 0 || ifo->req_addr.s_addr != INADDR_ANY) return; switch (type) { case RTM_DELADDR: if (ifp->state->new && ifp->state->new->yiaddr == addr->s_addr) drop_config(ifp, "EXPIRE"); break; case RTM_NEWADDR: free(ifp->state->old); ifp->state->old = ifp->state->new; ifp->state->new = dhcp_message_new(addr, net); ifp->dst.s_addr = dst ? dst->s_addr : INADDR_ANY; if (dst) { for (i = 1; i < 255; i++) if (i != DHO_ROUTER && has_option_mask(ifo->dstmask, i)) dhcp_message_add_addr( ifp->state->new, i, *dst); } ifp->state->reason = "STATIC"; build_routes(); run_script(ifp); if (ifo->options & DHCPCD_INFORM) { ifp->state->state = DHS_INFORM; ifp->state->xid = dhcp_xid(ifp); ifp->state->lease.server.s_addr = dst ? dst->s_addr : INADDR_ANY; ifp->addr = *addr; ifp->net = *net; send_inform(ifp); } break; } } /* ARGSUSED */ static void handle_link(_unused void *arg) { if (manage_link(linkfd) == -1) syslog(LOG_ERR, "manage_link: %m"); } static void if_reboot(struct interface *iface, int argc, char **argv) { const struct if_options *ifo; int opt; ifo = iface->state->options; opt = ifo->options; configure_interface(iface, argc, argv); ifo = iface->state->options; iface->state->interval = 0; if ((ifo->options & (DHCPCD_INFORM | DHCPCD_STATIC) && iface->addr.s_addr != ifo->req_addr.s_addr) || (opt & (DHCPCD_INFORM | DHCPCD_STATIC) && !(ifo->options & (DHCPCD_INFORM | DHCPCD_STATIC)))) { drop_config(iface, "EXPIRE"); } else { free(iface->state->offer); iface->state->offer = NULL; } start_interface(iface); } static void reconf_reboot(int action, int argc, char **argv, int oi) { struct interface *ifl, *ifn, *ifp, *ifs, *ift; ifs = discover_interfaces(argc - oi, argv + oi); if (ifs == NULL) return; /* Remove any old interfaces */ if (ifaces) { for (ifl = NULL; ifl != ifaces;) { /* Work our way backwards */ for (ifp = ifaces; ifp; ifp = ifp->next) if (ifp->next == ifl) { ifl = ifp; break; } for (ifn = ifs; ifn; ifn = ifn->next) if (strcmp(ifn->name, ifp->name) == 0) break; if (ifn == NULL) { ifl = ifp->next; stop_interface(ifp); } } } for (ifp = ifs; ifp && (ift = ifp->next, 1); ifp = ift) { ifl = NULL; for (ifn = ifaces; ifn; ifn = ifn->next) { if (strcmp(ifn->name, ifp->name) == 0) break; ifl = ifn; } if (ifn) { if (action) if_reboot(ifn, argc, argv); else if (ifn->state->new) configure(ifn); free_interface(ifp); } else { ifp->next = NULL; init_state(ifp, argc, argv); start_interface(ifp); if (ifl) ifl->next = ifp; else ifaces = ifp; } } sort_interfaces(); } /* ARGSUSED */ static void handle_signal(_unused void *arg) { struct interface *ifp, *ifl; struct if_options *ifo; int sig = signal_read(); int do_release, do_rebind, i; do_rebind = do_release = 0; switch (sig) { case SIGINT: syslog(LOG_INFO, "received SIGINT, stopping"); break; case SIGTERM: syslog(LOG_INFO, "received SIGTERM, stopping"); break; case SIGALRM: #ifdef ANDROID syslog(LOG_INFO, "received SIGALRM, renewing"); for (ifp = ifaces; ifp; ifp = ifp->next) { start_renew(ifp); } #else syslog(LOG_INFO, "received SIGALRM, rebinding"); for (i = 0; i < ifac; i++) free(ifav[i]); free(ifav); ifav = NULL; ifac = 0; for (i = 0; i < ifdc; i++) free(ifdv[i]); free(ifdv); ifdc = 0; ifdv = NULL; ifo = read_config(cffile, NULL, NULL, NULL); add_options(ifo, margc, margv); /* We need to preserve these two options. */ if (options & DHCPCD_MASTER) ifo->options |= DHCPCD_MASTER; if (options & DHCPCD_DAEMONISED) ifo->options |= DHCPCD_DAEMONISED; options = ifo->options; free_options(ifo); reconf_reboot(1, 0, NULL, 0); #endif return; case SIGHUP: syslog(LOG_INFO, "received SIGHUP, releasing"); do_release = 1; break; case SIGUSR1: syslog(LOG_INFO, "received SIGUSR, reconfiguring"); for (ifp = ifaces; ifp; ifp = ifp->next) if (ifp->state->new) configure(ifp); return; case SIGPIPE: syslog(LOG_WARNING, "received SIGPIPE"); return; default: syslog(LOG_ERR, "received signal %d, but don't know what to do with it", sig); return; } if (options & DHCPCD_TEST) exit(EXIT_FAILURE); /* As drop_config could re-arrange the order, we do it like this. */ for (;;) { /* Be sane and drop the last config first */ ifl = NULL; for (ifp = ifaces; ifp; ifp = ifp->next) { if (ifp->next == NULL) break; ifl = ifp; } if (ifp == NULL) break; if (ifp->carrier != LINK_DOWN && (do_release || ifp->state->options->options & DHCPCD_RELEASE)) send_release(ifp); stop_interface(ifp); } exit(EXIT_FAILURE); } int handle_args(struct fd_list *fd, int argc, char **argv) { struct interface *ifp; int do_exit = 0, do_release = 0, do_reboot = 0, do_reconf = 0; int opt, oi = 0; ssize_t len; size_t 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(cffile ? cffile : CONFIG) + 1; iov[0].iov_base = &len; iov[0].iov_len = sizeof(ssize_t); iov[1].iov_base = cffile ? cffile : UNCONST(CONFIG); 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) { for (ifp = ifaces; ifp; ifp = ifp->next) len++; len = write(fd->fd, &len, sizeof(len)); if (len != sizeof(len)) return -1; for (ifp = ifaces; ifp; ifp = ifp->next) send_interface(fd->fd, ifp); return 0; } opt = 0; while (argv[++opt] != NULL) { for (ifp = ifaces; ifp; ifp = ifp->next) if (strcmp(argv[opt], ifp->name) == 0) len++; } len = write(fd->fd, &len, sizeof(len)); if (len != sizeof(len)) return -1; opt = 0; while (argv[++opt] != NULL) { for (ifp = ifaces; ifp; ifp = ifp->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 = 0; for (opt = 0; opt < argc; opt++) len += strlen(argv[opt]) + 1; tmp = p = xmalloc(len + 1); for (opt = 0; opt < argc; opt++) { l = strlen(argv[opt]); strlcpy(p, argv[opt], 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': do_reconf = 1; break; case 'k': do_release = 1; break; case 'n': do_reboot = 1; break; case 'x': do_exit = 1; break; } } /* We need at least one interface */ if (optind == argc) { syslog(LOG_ERR, "handle_args: no interface"); return -1; } if (do_release || do_exit) { for (oi = optind; oi < argc; oi++) { for (ifp = ifaces; ifp; ifp = ifp->next) if (strcmp(ifp->name, argv[oi]) == 0) break; if (!ifp) continue; if (do_release) ifp->state->options->options |= DHCPCD_RELEASE; if (ifp->state->options->options & DHCPCD_RELEASE && ifp->carrier != LINK_DOWN) send_release(ifp); stop_interface(ifp); } return 0; } reconf_reboot(do_reboot, argc, argv, optind); return 0; } void open_sockets(struct interface *iface) { if (iface->raw_fd == -1) { if (open_socket(iface, ETHERTYPE_IP) == -1) syslog(LOG_ERR, "%s: open_socket: %m", iface->name); else add_event(iface->raw_fd, handle_dhcp_packet, iface); } if (iface->udp_fd == -1 && iface->addr.s_addr != 0 && iface->state->new != NULL && (iface->state->new->cookie == htonl(MAGIC_COOKIE) || iface->state->options->options & DHCPCD_INFORM)) { if (open_udp_socket(iface) == -1 && errno != EADDRINUSE) syslog(LOG_ERR, "%s: open_udp_socket: %m", iface->name); } } void close_sockets(struct interface *iface) { if (iface->arp_fd != -1) { delete_event(iface->arp_fd); close(iface->arp_fd); iface->arp_fd = -1; } if (iface->raw_fd != -1) { delete_event(iface->raw_fd); close(iface->raw_fd); iface->raw_fd = -1; } if (iface->udp_fd != -1) { /* we don't listen to events on the udp */ close(iface->udp_fd); iface->udp_fd = -1; } } #ifdef ANDROID void switchUser(void) { gid_t groups[] = { AID_INET, AID_SHELL }; struct __user_cap_header_struct header; struct __user_cap_data_struct cap; setgroups(sizeof(groups)/sizeof(groups[0]), groups); prctl(PR_SET_KEEPCAPS, 1, 0, 0, 0); setgid(AID_DHCP); setuid(AID_DHCP); header.version = _LINUX_CAPABILITY_VERSION; header.pid = 0; cap.effective = cap.permitted = (1 << CAP_NET_ADMIN) | (1 << CAP_NET_RAW) | (1 << CAP_NET_BROADCAST) | (1 << CAP_NET_BIND_SERVICE); cap.inheritable = 0; capset(&header, &cap); } #endif /* ANDROID */ int main(int argc, char **argv) { struct interface *iface; int opt, oi = 0, signal_fd, sig = 0, i, control_fd; size_t len; pid_t pid; struct timespec ts; #ifdef ANDROID switchUser(); #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(); exit(EXIT_SUCCESS); } else if (strcmp(argv[1], "--version") == 0) { printf(""PACKAGE" "VERSION"\n%s\n", copyright); exit(EXIT_SUCCESS); } } i = 0; while ((opt = getopt_long(argc, argv, IF_OPTS, cf_options, &oi)) != -1) { switch (opt) { case 'f': cffile = optarg; break; case 'g': sig = SIGUSR1; break; case 'k': sig = SIGHUP; break; case 'n': sig = SIGALRM; break; case 'x': sig = SIGTERM; break; case 'T': i = 1; break; case 'U': i = 2; break; case 'V': print_options(); exit(EXIT_SUCCESS); case '?': usage(); exit(EXIT_FAILURE); } } margv = argv; margc = argc; if_options = read_config(cffile, NULL, NULL, NULL); opt = add_options(if_options, argc, argv); if (opt != 1) { if (opt == 0) usage(); exit(EXIT_FAILURE); } options = if_options->options; if (i != 0) { if (i == 1) options |= DHCPCD_TEST; else options |= DHCPCD_DUMPLEASE; options |= DHCPCD_PERSISTENT; options &= ~DHCPCD_DAEMONISE; } #ifdef THERE_IS_NO_FORK options &= ~DHCPCD_DAEMONISE; #endif if (options & DHCPCD_DEBUG) setlogmask(LOG_UPTO(LOG_DEBUG)); if (options & DHCPCD_QUIET) close(STDERR_FILENO); if (!(options & (DHCPCD_TEST | DHCPCD_DUMPLEASE))) { /* If we have any other args, we should run as a single dhcpcd * instance for that interface. */ len = strlen(PIDFILE) + IF_NAMESIZE + 2; pidfile = xmalloc(len); if (optind == argc - 1) snprintf(pidfile, len, PIDFILE, "-", argv[optind]); else { snprintf(pidfile, len, PIDFILE, "", ""); options |= DHCPCD_MASTER; } } if (chdir("/") == -1) syslog(LOG_ERR, "chdir `/': %m"); atexit(cleanup); if (options & DHCPCD_DUMPLEASE) { if (optind != argc - 1) { syslog(LOG_ERR, "dumplease requires an interface"); exit(EXIT_FAILURE); } ifaces = iface = xzalloc(sizeof(*iface)); strlcpy(iface->name, argv[optind], sizeof(iface->name)); snprintf(iface->leasefile, sizeof(iface->leasefile), LEASEFILE, iface->name); iface->state = xzalloc(sizeof(*iface->state)); iface->state->options = xzalloc(sizeof(*iface->state->options)); strlcpy(iface->state->options->script, if_options->script, sizeof(iface->state->options->script)); iface->state->new = read_lease(iface); if (iface->state->new == NULL && errno == ENOENT) { strlcpy(iface->leasefile, argv[optind], sizeof(iface->leasefile)); iface->state->new = read_lease(iface); } if (iface->state->new == NULL) { if (errno == ENOENT) syslog(LOG_ERR, "%s: no lease to dump", iface->name); exit(EXIT_FAILURE); } iface->state->reason = "DUMP"; run_script(iface); exit(EXIT_SUCCESS); } if (!(options & (DHCPCD_MASTER | DHCPCD_TEST))) { control_fd = open_control(); if (control_fd != -1) { syslog(LOG_INFO, "sending commands to master dhcpcd process"); i = send_control(argc, argv); if (i > 0) { syslog(LOG_DEBUG, "send OK"); exit(EXIT_SUCCESS); } else { syslog(LOG_ERR, "failed to send commands"); exit(EXIT_FAILURE); } } else { if (errno != ENOENT) syslog(LOG_ERR, "open_control: %m"); } } #ifndef ANDROID /* android runs us as user "dhcp" */ if (geteuid()) syslog(LOG_WARNING, PACKAGE " will not work correctly unless run as root"); #endif if (sig != 0) { #ifdef ANDROID char pidpropname[PROPERTY_KEY_MAX]; char pidpropval[PROPERTY_VALUE_MAX]; if (optind != argc - 1) { syslog(LOG_ERR, "Android requires an interface"); exit(EXIT_FAILURE); } if (snprintf(pidpropname, sizeof(pidpropname), "dhcp.%s.pid", argv[optind]) >= PROPERTY_KEY_MAX) exit(EXIT_FAILURE); property_get(pidpropname, pidpropval, NULL); if (strlen(pidpropval) == 0) exit(EXIT_FAILURE); pid = atoi(pidpropval); #else pid = read_pid(); #endif if (pid != 0) syslog(LOG_INFO, "sending signal %d to pid %d", sig, pid); if (pid == 0 || kill(pid, sig) != 0) { if (sig != SIGALRM) syslog(LOG_ERR, ""PACKAGE" not running"); if (pid != 0 && errno != ESRCH) { syslog(LOG_ERR, "kill: %m"); exit(EXIT_FAILURE); } unlink(pidfile); if (sig != SIGALRM) exit(EXIT_FAILURE); } else { if (sig == SIGALRM) exit(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() == 0) exit(EXIT_SUCCESS); } syslog(LOG_ERR, "pid %d failed to exit", pid); exit(EXIT_FAILURE); } } if (!(options & DHCPCD_TEST)) { #ifdef ANDROID char pidpropname[PROPERTY_KEY_MAX]; char pidpropval[PROPERTY_VALUE_MAX]; #endif #ifndef ANDROID if ((pid = read_pid()) > 0 && kill(pid, 0) == 0) { syslog(LOG_ERR, ""PACKAGE " already running on pid %d (%s)", pid, pidfile); exit(EXIT_FAILURE); } /* Ensure we have the needed directories */ if (mkdir(RUNDIR, 0755) == -1 && errno != EEXIST) { syslog(LOG_ERR, "mkdir `%s': %m", RUNDIR); exit(EXIT_FAILURE); } if (mkdir(DBDIR, 0755) == -1 && errno != EEXIST) { syslog(LOG_ERR, "mkdir `%s': %m", DBDIR); exit(EXIT_FAILURE); } #endif pidfd = open(pidfile, O_WRONLY | O_CREAT | O_NONBLOCK, 0664); if (pidfd == -1) { syslog(LOG_ERR, "open `%s': %m", pidfile); exit(EXIT_FAILURE); } /* Lock the file so that only one instance of dhcpcd runs * on an interface */ if (flock(pidfd, LOCK_EX | LOCK_NB) == -1) { syslog(LOG_ERR, "flock `%s': %m", pidfile); exit(EXIT_FAILURE); } if (set_cloexec(pidfd) == -1) exit(EXIT_FAILURE); #ifdef ANDROID if (optind != argc - 1) { syslog(LOG_ERR, "Android requires an interface"); exit(EXIT_FAILURE); } if (snprintf(pidpropname, sizeof(pidpropname), "dhcp.%s.pid", argv[optind]) >= PROPERTY_KEY_MAX) exit(EXIT_FAILURE); if (snprintf(pidpropval, sizeof(pidpropval), "%d", getpid()) >= PROPERTY_VALUE_MAX) exit(EXIT_FAILURE); property_set(pidpropname, pidpropval); #else writepid(pidfd, getpid()); #endif } syslog(LOG_INFO, "version " VERSION " starting"); if ((signal_fd = signal_init()) == -1) exit(EXIT_FAILURE); if (signal_setup() == -1) exit(EXIT_FAILURE); add_event(signal_fd, handle_signal, NULL); if (options & DHCPCD_MASTER) { if (start_control() == -1) { syslog(LOG_ERR, "start_control: %m"); exit(EXIT_FAILURE); } } if (init_sockets() == -1) { syslog(LOG_ERR, "init_socket: %m"); exit(EXIT_FAILURE); } if (if_options->options & DHCPCD_LINK) { linkfd = open_link_socket(); if (linkfd == -1) syslog(LOG_ERR, "open_link_socket: %m"); else add_event(linkfd, handle_link, NULL); } ifc = argc - optind; ifv = argv + optind; /* When running dhcpcd against a single interface, we need to retain * the old behaviour of waiting for an IP address */ if (ifc == 1) options |= DHCPCD_WAITIP; ifaces = discover_interfaces(ifc, ifv); for (i = 0; i < ifc; i++) { for (iface = ifaces; iface; iface = iface->next) if (strcmp(iface->name, ifv[i]) == 0) break; if (!iface) syslog(LOG_ERR, "%s: interface not found or invalid", ifv[i]); } if (!ifaces) { if (ifc == 0) syslog(LOG_ERR, "no valid interfaces found"); else exit(EXIT_FAILURE); if (!(options & DHCPCD_LINK)) { syslog(LOG_ERR, "aborting as link detection is disabled"); exit(EXIT_FAILURE); } } if (options & DHCPCD_BACKGROUND) daemonise(); opt = 0; for (iface = ifaces; iface; iface = iface->next) { init_state(iface, argc, argv); if (iface->carrier != LINK_DOWN) opt = 1; } if (!(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 && options & DHCPCD_LINK && options & DHCPCD_WAITUP && !(options & DHCPCD_WAITIP)) { ts.tv_sec = 1; ts.tv_nsec = 0; nanosleep(&ts, NULL); for (iface = ifaces; iface; iface = iface->next) { handle_carrier(iface->name); if (iface->carrier != LINK_DOWN) { opt = 1; break; } } } if (opt == 0 && options & DHCPCD_LINK && !(options & DHCPCD_WAITIP)) { syslog(LOG_WARNING, "no interfaces have a carrier"); daemonise(); } else if (if_options->timeout > 0) { if (options & DHCPCD_IPV4LL) options |= DHCPCD_TIMEOUT_IPV4LL; add_timeout_sec(if_options->timeout, handle_exit_timeout, NULL); } } free_options(if_options); if_options = NULL; sort_interfaces(); for (iface = ifaces; iface; iface = iface->next) add_timeout_sec(0, start_interface, iface); start_eloop(); exit(EXIT_SUCCESS); }