+/* vi: set sw=4 ts=4: */
/* dhcpc.c
*
* udhcp DHCP client
*
* Russ Dill <Russ.Dill@asu.edu> July 2001
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
*/
-
-#include <sys/time.h>
-#include <sys/file.h>
-#include <unistd.h>
+
#include <getopt.h>
-#include <stdlib.h>
-#include <sys/socket.h>
-#include <netinet/in.h>
-#include <arpa/inet.h>
-#include <signal.h>
-#include <time.h>
-#include <string.h>
-#include <sys/ioctl.h>
-#include <net/if.h>
-#include <errno.h>
+#include "common.h"
#include "dhcpd.h"
#include "dhcpc.h"
#include "options.h"
-#include "clientpacket.h"
-#include "script.h"
-#include "socket.h"
-#include "common.h"
+
static int state;
+/* Something is definitely wrong here. IPv4 addresses
+ * in variables of type long?? BTW, we use inet_ntoa()
+ * in the code. Manpage says that struct in_addr has a member of type long (!)
+ * which holds IPv4 address, and the struct is passed by value (!!)
+ */
static unsigned long requested_ip; /* = 0 */
static unsigned long server_addr;
static unsigned long timeout;
#define LISTEN_RAW 2
static int listen_mode;
-#ifdef CONFIG_INSTALL_NO_USR
-#define DEFAULT_SCRIPT "/share/udhcpc/default.script"
-#else
-#define DEFAULT_SCRIPT "/usr/share/udhcpc/default.script"
-#endif
+struct client_config_t client_config;
-struct client_config_t client_config = {
- /* Default options. */
- abort_if_no_lease: 0,
- foreground: 0,
- quit_after_lease: 0,
- background_if_no_lease: 0,
- interface: "eth0",
- pidfile: NULL,
- script: DEFAULT_SCRIPT,
- clientid: NULL,
- hostname: NULL,
- ifindex: 0,
- arp: "\0\0\0\0\0\0", /* appease gcc-3.0 */
-};
/* just a little helper */
static void change_mode(int new_mode)
{
- DEBUG(LOG_INFO, "entering %s listen mode",
+ DEBUG("entering %s listen mode",
new_mode ? (new_mode == 1 ? "kernel" : "raw") : "none");
if (fd >= 0) close(fd);
fd = -1;
/* perform a renew */
static void perform_renew(void)
{
- LOG(LOG_INFO, "Performing a DHCP renew");
+ bb_info_msg("Performing a DHCP renew");
switch (state) {
case BOUND:
change_mode(LISTEN_KERNEL);
state = RENEW_REQUESTED;
break;
case RENEW_REQUESTED: /* impatient are we? fine, square 1 */
- run_script(NULL, "deconfig");
+ udhcp_run_script(NULL, "deconfig");
case REQUESTING:
case RELEASED:
change_mode(LISTEN_RAW);
temp_addr.s_addr = server_addr;
sprintf(buffer, "%s", inet_ntoa(temp_addr));
temp_addr.s_addr = requested_ip;
- LOG(LOG_INFO, "Unicasting a release of %s to %s",
+ bb_info_msg("Unicasting a release of %s to %s",
inet_ntoa(temp_addr), buffer);
send_release(server_addr, requested_ip); /* unicast */
- run_script(NULL, "deconfig");
+ udhcp_run_script(NULL, "deconfig");
}
- LOG(LOG_INFO, "Entering released state");
+ bb_info_msg("Entering released state");
change_mode(LISTEN_NONE);
state = RELEASED;
static void client_background(void)
{
- background(client_config.pidfile);
+ udhcp_background(client_config.pidfile);
client_config.foreground = 1; /* Do not fork again. */
client_config.background_if_no_lease = 0;
}
+static uint8_t* alloc_dhcp_option(int code, const char *str, int extra)
+{
+ uint8_t *storage;
+ int len = strlen(str);
+ if (len > 255) len = 255;
+ storage = xzalloc(len + extra + OPT_DATA);
+ storage[OPT_CODE] = code;
+ storage[OPT_LEN] = len + extra;
+ memcpy(storage + extra + OPT_DATA, str, len);
+ return storage;
+}
+
+
int udhcpc_main(int argc, char *argv[])
{
- unsigned char *temp, *message;
+ uint8_t *temp, *message;
+ char *str_c, *str_V, *str_h, *str_F, *str_r, *str_T, *str_t;
unsigned long t1 = 0, t2 = 0, xid = 0;
- unsigned long start = 0, lease;
- fd_set rfds;
+ unsigned long start = 0, lease = 0;
+ long now;
+ unsigned opt;
+ int max_fd;
+ int sig;
int retval;
+ int len;
+ int no_clientid = 0;
+ fd_set rfds;
struct timeval tv;
- int c, len;
struct dhcpMessage packet;
struct in_addr temp_addr;
- time_t now;
- int max_fd;
- int sig;
+ enum {
+ OPT_c = 1 << 0,
+ OPT_C = 1 << 1,
+ OPT_V = 1 << 2,
+ OPT_f = 1 << 3,
+ OPT_b = 1 << 4,
+ OPT_H = 1 << 5,
+ OPT_h = 1 << 6,
+ OPT_F = 1 << 7,
+ OPT_i = 1 << 8,
+ OPT_n = 1 << 9,
+ OPT_p = 1 << 10,
+ OPT_q = 1 << 11,
+ OPT_R = 1 << 12,
+ OPT_r = 1 << 13,
+ OPT_s = 1 << 14,
+ OPT_T = 1 << 15,
+ OPT_t = 1 << 16,
+ OPT_v = 1 << 17,
+ };
+#if ENABLE_GETOPT_LONG
static const struct option arg_options[] = {
- {"clientid", required_argument, 0, 'c'},
- {"foreground", no_argument, 0, 'f'},
- {"background", no_argument, 0, 'b'},
- {"hostname", required_argument, 0, 'H'},
- {"hostname", required_argument, 0, 'h'},
- {"interface", required_argument, 0, 'i'},
- {"now", no_argument, 0, 'n'},
- {"pidfile", required_argument, 0, 'p'},
- {"quit", no_argument, 0, 'q'},
- {"request", required_argument, 0, 'r'},
- {"script", required_argument, 0, 's'},
- {"version", no_argument, 0, 'v'},
- {0, 0, 0, 0}
+ { "clientid", required_argument, 0, 'c' },
+ { "clientid-none", no_argument, 0, 'C' },
+ { "vendorclass", required_argument, 0, 'V' },
+ { "foreground", no_argument, 0, 'f' },
+ { "background", no_argument, 0, 'b' },
+ { "hostname", required_argument, 0, 'H' },
+ { "hostname", required_argument, 0, 'h' },
+ { "fqdn", required_argument, 0, 'F' },
+ { "interface", required_argument, 0, 'i' },
+ { "now", no_argument, 0, 'n' },
+ { "pidfile", required_argument, 0, 'p' },
+ { "quit", no_argument, 0, 'q' },
+ { "release", no_argument, 0, 'R' },
+ { "request", required_argument, 0, 'r' },
+ { "script", required_argument, 0, 's' },
+ { "timeout", required_argument, 0, 'T' },
+ { "version", no_argument, 0, 'v' },
+ { "retries", required_argument, 0, 't' },
+ { 0, 0, 0, 0 }
};
+#endif
+ /* Default options. */
+ client_config.interface = "eth0";
+ client_config.script = DEFAULT_SCRIPT;
+ client_config.retries = 3;
+ client_config.timeout = 3;
- /* get options */
- while (1) {
- int option_index = 0;
- c = getopt_long(argc, argv, "c:fbH:h:i:np:qr:s:v", arg_options, &option_index);
- if (c == -1) break;
-
- switch (c) {
- case 'c':
- len = strlen(optarg) > 255 ? 255 : strlen(optarg);
- if (client_config.clientid) free(client_config.clientid);
- client_config.clientid = xmalloc(len + 2);
- client_config.clientid[OPT_CODE] = DHCP_CLIENT_ID;
- client_config.clientid[OPT_LEN] = len;
- client_config.clientid[OPT_DATA] = '\0';
- strncpy(client_config.clientid + OPT_DATA, optarg, len);
- break;
- case 'f':
- client_config.foreground = 1;
- break;
- case 'b':
- client_config.background_if_no_lease = 1;
- break;
- case 'h':
- case 'H':
- len = strlen(optarg) > 255 ? 255 : strlen(optarg);
- if (client_config.hostname) free(client_config.hostname);
- client_config.hostname = xmalloc(len + 2);
- client_config.hostname[OPT_CODE] = DHCP_HOST_NAME;
- client_config.hostname[OPT_LEN] = len;
- strncpy(client_config.hostname + 2, optarg, len);
- break;
- case 'i':
- client_config.interface = optarg;
- break;
- case 'n':
- client_config.abort_if_no_lease = 1;
- break;
- case 'p':
- client_config.pidfile = optarg;
- break;
- case 'q':
- client_config.quit_after_lease = 1;
- break;
- case 'r':
- requested_ip = inet_addr(optarg);
- break;
- case 's':
- client_config.script = optarg;
- break;
- case 'v':
- bb_error_msg("version %s\n", VERSION);
- return(0);
- break;
- default:
- bb_show_usage();
- }
+ /* Parse command line */
+ opt_complementary = "?:c--C:C--c" // mutually exclusive
+ ":hH:Hh"; // -h and -H are the same
+#if ENABLE_GETOPT_LONG
+ applet_long_options = arg_options;
+#endif
+ opt = getopt32(argc, argv, "c:CV:fbH:h:F:i:np:qRr:s:T:t:v",
+ &str_c, &str_V, &str_h, &str_h, &str_F,
+ &client_config.interface, &client_config.pidfile, &str_r,
+ &client_config.script, &str_T, &str_t
+ );
+
+ if (opt & OPT_c)
+ client_config.clientid = alloc_dhcp_option(DHCP_CLIENT_ID, str_c, 0);
+ if (opt & OPT_C)
+ no_clientid = 1;
+ if (opt & OPT_V)
+ client_config.vendorclass = alloc_dhcp_option(DHCP_VENDOR, str_V, 0);
+ if (opt & OPT_f)
+ client_config.foreground = 1;
+ if (opt & OPT_b)
+ client_config.background_if_no_lease = 1;
+ if (opt & OPT_h)
+ client_config.hostname = alloc_dhcp_option(DHCP_HOST_NAME, str_h, 0);
+ if (opt & OPT_F) {
+ client_config.fqdn = alloc_dhcp_option(DHCP_FQDN, str_F, 3);
+ /* Flags: 0000NEOS
+ S: 1 => Client requests Server to update A RR in DNS as well as PTR
+ O: 1 => Server indicates to client that DNS has been updated regardless
+ E: 1 => Name data is DNS format, i.e. <4>host<6>domain<4>com<0> not "host.domain.com"
+ N: 1 => Client requests Server to not update DNS
+ */
+ client_config.fqdn[OPT_DATA + 0] = 0x1;
+ /* client_config.fqdn[OPT_DATA + 1] = 0; - redundant */
+ /* client_config.fqdn[OPT_DATA + 2] = 0; - redundant */
}
+ // if (opt & OPT_i) client_config.interface = ...
+ if (opt & OPT_n)
+ client_config.abort_if_no_lease = 1;
+ // if (opt & OPT_p) client_config.pidfile = ...
+ if (opt & OPT_q)
+ client_config.quit_after_lease = 1;
+ if (opt & OPT_R)
+ client_config.release_on_quit = 1;
+ if (opt & OPT_r)
+ requested_ip = inet_addr(str_r);
+ // if (opt & OPT_s) client_config.script = ...
+ if (opt & OPT_T)
+ client_config.timeout = xatoi_u(str_T);
+ if (opt & OPT_t)
+ client_config.retries = xatoi_u(str_t);
+ if (opt & OPT_v) {
+ printf("version %s\n\n", BB_VER);
+ return 0;
+ }
+
+ /* Start the log, sanitize fd's, and write a pid file */
+ udhcp_start_log_and_pid(client_config.pidfile);
- start_log("client");
- if (read_interface(client_config.interface, &client_config.ifindex,
+ if (read_interface(client_config.interface, &client_config.ifindex,
NULL, client_config.arp) < 0)
- return(1);
-
- if (!client_config.clientid) {
- client_config.clientid = xmalloc(6 + 3);
- client_config.clientid[OPT_CODE] = DHCP_CLIENT_ID;
- client_config.clientid[OPT_LEN] = 7;
+ return 1;
+
+ /* if not set, and not suppressed, setup the default client ID */
+ if (!client_config.clientid && !no_clientid) {
+ client_config.clientid = alloc_dhcp_option(DHCP_CLIENT_ID, "", 7);
client_config.clientid[OPT_DATA] = 1;
- memcpy(client_config.clientid + 3, client_config.arp, 6);
+ memcpy(client_config.clientid + OPT_DATA+1, client_config.arp, 6);
}
- /* setup signal handlers */
- udhcp_set_signal_pipe(SIGUSR2);
-
+ if (!client_config.vendorclass)
+ client_config.vendorclass = alloc_dhcp_option(DHCP_VENDOR, "udhcp "BB_VER, 0);
+
+ /* setup the signal pipe */
+ udhcp_sp_setup();
+
state = INIT_SELECTING;
- run_script(NULL, "deconfig");
+ udhcp_run_script(NULL, "deconfig");
change_mode(LISTEN_RAW);
for (;;) {
-
- tv.tv_sec = timeout - time(0);
+ tv.tv_sec = timeout - uptime();
tv.tv_usec = 0;
- FD_ZERO(&rfds);
if (listen_mode != LISTEN_NONE && fd < 0) {
if (listen_mode == LISTEN_KERNEL)
fd = listen_socket(INADDR_ANY, CLIENT_PORT, client_config.interface);
else
fd = raw_socket(client_config.ifindex);
- if (fd < 0) {
- LOG(LOG_ERR, "FATAL: couldn't listen on socket, %m");
- return(0);
- }
}
- if (fd >= 0) FD_SET(fd, &rfds);
- FD_SET(udhcp_signal_pipe[0], &rfds);
+ max_fd = udhcp_sp_fd_set(&rfds, fd);
if (tv.tv_sec > 0) {
- DEBUG(LOG_INFO, "Waiting on select...\n");
- max_fd = udhcp_signal_pipe[0] > fd ? udhcp_signal_pipe[0] : fd;
+ DEBUG("Waiting on select...");
retval = select(max_fd + 1, &rfds, NULL, NULL, &tv);
} else retval = 0; /* If we already timed out, fall through */
- now = time(0);
+ now = uptime();
if (retval == 0) {
/* timeout dropped to zero */
switch (state) {
case INIT_SELECTING:
- if (packet_num < 3) {
+ if (packet_num < client_config.retries) {
if (packet_num == 0)
xid = random_xid();
/* send discover packet */
send_discover(xid, requested_ip); /* broadcast */
-
- timeout = now + ((packet_num == 2) ? 4 : 2);
+
+ timeout = now + client_config.timeout;
packet_num++;
} else {
+ udhcp_run_script(NULL, "leasefail");
if (client_config.background_if_no_lease) {
- LOG(LOG_INFO, "No lease, forking to background.");
+ bb_info_msg("No lease, forking to background");
client_background();
} else if (client_config.abort_if_no_lease) {
- LOG(LOG_INFO, "No lease, failing.");
- return(1);
- }
+ bb_info_msg("No lease, failing");
+ return 1;
+ }
/* wait to try again */
packet_num = 0;
timeout = now + 60;
break;
case RENEW_REQUESTED:
case REQUESTING:
- if (packet_num < 3) {
+ if (packet_num < client_config.retries) {
/* send request packet */
if (state == RENEW_REQUESTED)
send_renew(xid, server_addr, requested_ip); /* unicast */
else send_selecting(xid, server_addr, requested_ip); /* broadcast */
-
+
timeout = now + ((packet_num == 2) ? 10 : 2);
packet_num++;
} else {
/* timed out, go back to init state */
- if (state == RENEW_REQUESTED) run_script(NULL, "deconfig");
+ if (state == RENEW_REQUESTED) udhcp_run_script(NULL, "deconfig");
state = INIT_SELECTING;
timeout = now;
packet_num = 0;
/* Lease is starting to run out, time to enter renewing state */
state = RENEWING;
change_mode(LISTEN_KERNEL);
- DEBUG(LOG_INFO, "Entering renew state");
+ DEBUG("Entering renew state");
/* fall right through */
case RENEWING:
/* Either set a new T1, or enter REBINDING state */
/* timed out, enter rebinding state */
state = REBINDING;
timeout = now + (t2 - t1);
- DEBUG(LOG_INFO, "Entering rebinding state");
+ DEBUG("Entering rebinding state");
} else {
/* send a request packet */
send_renew(xid, server_addr, requested_ip); /* unicast */
-
+
t1 = (t2 - t1) / 2 + t1;
timeout = t1 + start;
}
if ((lease - t2) <= (lease / 14400 + 1)) {
/* timed out, enter init state */
state = INIT_SELECTING;
- LOG(LOG_INFO, "Lease lost, entering init state");
- run_script(NULL, "deconfig");
+ bb_info_msg("Lease lost, entering init state");
+ udhcp_run_script(NULL, "deconfig");
timeout = now;
packet_num = 0;
change_mode(LISTEN_RAW);
}
} else if (retval > 0 && listen_mode != LISTEN_NONE && FD_ISSET(fd, &rfds)) {
/* a packet is ready, read it */
-
+
if (listen_mode == LISTEN_KERNEL)
- len = get_packet(&packet, fd);
+ len = udhcp_get_packet(&packet, fd);
else len = get_raw_packet(&packet, fd);
-
+
if (len == -1 && errno != EINTR) {
- DEBUG(LOG_INFO, "error on read, %m, reopening socket");
+ DEBUG("error on read, %s, reopening socket", strerror(errno));
change_mode(listen_mode); /* just close and reopen */
}
if (len < 0) continue;
-
+
if (packet.xid != xid) {
- DEBUG(LOG_INFO, "Ignoring XID %lx (our xid is %lx)",
+ DEBUG("Ignoring XID %lx (our xid is %lx)",
(unsigned long) packet.xid, xid);
continue;
}
-
+
+ /* Ignore packets that aren't for us */
+ if (memcmp(packet.chaddr, client_config.arp, 6)) {
+ DEBUG("Packet does not have our chaddr - ignoring");
+ continue;
+ }
+
if ((message = get_option(&packet, DHCP_MESSAGE_TYPE)) == NULL) {
- DEBUG(LOG_ERR, "couldnt get option from packet -- ignoring");
+ bb_error_msg("cannot get option from packet - ignoring");
continue;
}
-
+
switch (state) {
case INIT_SELECTING:
/* Must be a DHCPOFFER to one of our xid's */
if (*message == DHCPOFFER) {
- if ((temp = get_option(&packet, DHCP_SERVER_ID))) {
- memcpy(&server_addr, temp, 4);
+ temp = get_option(&packet, DHCP_SERVER_ID);
+ if (temp) {
+ server_addr = *(uint32_t*)temp;
xid = packet.xid;
requested_ip = packet.yiaddr;
-
+
/* enter requesting state */
state = REQUESTING;
timeout = now;
packet_num = 0;
} else {
- DEBUG(LOG_ERR, "No server ID in message");
+ bb_error_msg("no server ID in message");
}
}
break;
case RENEWING:
case REBINDING:
if (*message == DHCPACK) {
- if (!(temp = get_option(&packet, DHCP_LEASE_TIME))) {
- LOG(LOG_ERR, "No lease time with ACK, using 1 hour lease");
+ temp = get_option(&packet, DHCP_LEASE_TIME);
+ if (!temp) {
+ bb_error_msg("no lease time with ACK, using 1 hour lease");
lease = 60 * 60;
} else {
- memcpy(&lease, temp, 4);
- lease = ntohl(lease);
+ lease = ntohl(*(uint32_t*)temp);
}
-
+
/* enter bound state */
t1 = lease / 2;
-
+
/* little fixed point for n * .875 */
t2 = (lease * 0x7) >> 3;
temp_addr.s_addr = packet.yiaddr;
- LOG(LOG_INFO, "Lease of %s obtained, lease time %ld",
+ bb_info_msg("Lease of %s obtained, lease time %ld",
inet_ntoa(temp_addr), lease);
start = now;
timeout = t1 + start;
requested_ip = packet.yiaddr;
- run_script(&packet,
+ udhcp_run_script(&packet,
((state == RENEWING || state == REBINDING) ? "renew" : "bound"));
state = BOUND;
change_mode(LISTEN_NONE);
- if (client_config.quit_after_lease)
- return(0);
+ if (client_config.quit_after_lease) {
+ if (client_config.release_on_quit)
+ perform_release();
+ return 0;
+ }
if (!client_config.foreground)
client_background();
} else if (*message == DHCPNAK) {
/* return to init state */
- LOG(LOG_INFO, "Received DHCP NAK");
- run_script(&packet, "nak");
+ bb_info_msg("Received DHCP NAK");
+ udhcp_run_script(&packet, "nak");
if (state != REQUESTING)
- run_script(NULL, "deconfig");
+ udhcp_run_script(NULL, "deconfig");
state = INIT_SELECTING;
timeout = now;
requested_ip = 0;
}
break;
/* case BOUND, RELEASED: - ignore all packets */
- }
- } else if (retval > 0 && FD_ISSET(udhcp_signal_pipe[0], &rfds)) {
- if (read(udhcp_signal_pipe[0], &sig, sizeof(sig)) < 0) {
- DEBUG(LOG_ERR, "Could not read signal: %m");
- continue; /* probably just EINTR */
}
+ } else if (retval > 0 && (sig = udhcp_sp_read(&rfds))) {
switch (sig) {
- case SIGUSR1:
+ case SIGUSR1:
perform_renew();
break;
case SIGUSR2:
perform_release();
break;
case SIGTERM:
- LOG(LOG_INFO, "Received SIGTERM");
- return(0);
+ bb_info_msg("Received SIGTERM");
+ if (client_config.release_on_quit)
+ perform_release();
+ return 0;
}
} else if (retval == -1 && errno == EINTR) {
- /* a signal was caught */
+ /* a signal was caught */
} else {
/* An error occured */
- DEBUG(LOG_ERR, "Error on select");
+ bb_perror_msg("select");
}
-
+
}
return 0;
}