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Diffstat (limited to 'i/pc104/initrd/conf/busybox/networking/udhcp/dhcpc.c')
-rw-r--r--i/pc104/initrd/conf/busybox/networking/udhcp/dhcpc.c509
1 files changed, 509 insertions, 0 deletions
diff --git a/i/pc104/initrd/conf/busybox/networking/udhcp/dhcpc.c b/i/pc104/initrd/conf/busybox/networking/udhcp/dhcpc.c
new file mode 100644
index 0000000..a59c5db
--- /dev/null
+++ b/i/pc104/initrd/conf/busybox/networking/udhcp/dhcpc.c
@@ -0,0 +1,509 @@
+/* vi: set sw=4 ts=4: */
+/* dhcpc.c
+ *
+ * udhcp DHCP client
+ *
+ * Russ Dill <Russ.Dill@asu.edu> July 2001
+ *
+ * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
+ */
+
+#include <getopt.h>
+
+#include "common.h"
+#include "dhcpd.h"
+#include "dhcpc.h"
+#include "options.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 uint32_t server_addr;
+static unsigned long timeout;
+static int packet_num; /* = 0 */
+static int fd = -1;
+
+#define LISTEN_NONE 0
+#define LISTEN_KERNEL 1
+#define LISTEN_RAW 2
+static int listen_mode;
+
+struct client_config_t client_config;
+
+
+/* just a little helper */
+static void change_mode(int new_mode)
+{
+ DEBUG("entering %s listen mode",
+ new_mode ? (new_mode == 1 ? "kernel" : "raw") : "none");
+ if (fd >= 0) close(fd);
+ fd = -1;
+ listen_mode = new_mode;
+}
+
+
+/* perform a renew */
+static void perform_renew(void)
+{
+ bb_info_msg("Performing a DHCP renew");
+ switch (state) {
+ case BOUND:
+ change_mode(LISTEN_KERNEL);
+ case RENEWING:
+ case REBINDING:
+ state = RENEW_REQUESTED;
+ break;
+ case RENEW_REQUESTED: /* impatient are we? fine, square 1 */
+ udhcp_run_script(NULL, "deconfig");
+ case REQUESTING:
+ case RELEASED:
+ change_mode(LISTEN_RAW);
+ state = INIT_SELECTING;
+ break;
+ case INIT_SELECTING:
+ break;
+ }
+
+ /* start things over */
+ packet_num = 0;
+
+ /* Kill any timeouts because the user wants this to hurry along */
+ timeout = 0;
+}
+
+
+/* perform a release */
+static void perform_release(void)
+{
+ char buffer[16];
+ struct in_addr temp_addr;
+
+ /* send release packet */
+ if (state == BOUND || state == RENEWING || state == REBINDING) {
+ temp_addr.s_addr = server_addr;
+ sprintf(buffer, "%s", inet_ntoa(temp_addr));
+ temp_addr.s_addr = requested_ip;
+ bb_info_msg("Unicasting a release of %s to %s",
+ inet_ntoa(temp_addr), buffer);
+ send_release(server_addr, requested_ip); /* unicast */
+ udhcp_run_script(NULL, "deconfig");
+ }
+ bb_info_msg("Entering released state");
+
+ change_mode(LISTEN_NONE);
+ state = RELEASED;
+ timeout = 0x7fffffff;
+}
+
+
+static void client_background(void)
+{
+ 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[]);
+int udhcpc_main(int argc, char *argv[])
+{
+ 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 = 0;
+ long now;
+ unsigned opt;
+ int max_fd;
+ int sig;
+ int retval;
+ int len;
+ int no_clientid = 0;
+ fd_set rfds;
+ struct timeval tv;
+ struct dhcpMessage packet;
+ struct in_addr temp_addr;
+
+ 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' },
+ { "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;
+
+ /* 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);
+
+ if (read_interface(client_config.interface, &client_config.ifindex,
+ NULL, client_config.arp) < 0)
+ 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 + OPT_DATA+1, client_config.arp, 6);
+ }
+
+ 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;
+ udhcp_run_script(NULL, "deconfig");
+ change_mode(LISTEN_RAW);
+
+ for (;;) {
+ tv.tv_sec = timeout - uptime();
+ tv.tv_usec = 0;
+
+ 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);
+ }
+ max_fd = udhcp_sp_fd_set(&rfds, fd);
+
+ if (tv.tv_sec > 0) {
+ DEBUG("Waiting on select...");
+ retval = select(max_fd + 1, &rfds, NULL, NULL, &tv);
+ } else retval = 0; /* If we already timed out, fall through */
+
+ now = uptime();
+ if (retval == 0) {
+ /* timeout dropped to zero */
+ switch (state) {
+ case INIT_SELECTING:
+ if (packet_num < client_config.retries) {
+ if (packet_num == 0)
+ xid = random_xid();
+
+ /* send discover packet */
+ send_discover(xid, requested_ip); /* broadcast */
+
+ timeout = now + client_config.timeout;
+ packet_num++;
+ } else {
+ udhcp_run_script(NULL, "leasefail");
+ if (client_config.background_if_no_lease) {
+ bb_info_msg("No lease, forking to background");
+ client_background();
+ } else if (client_config.abort_if_no_lease) {
+ 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 < 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) udhcp_run_script(NULL, "deconfig");
+ state = INIT_SELECTING;
+ timeout = now;
+ packet_num = 0;
+ change_mode(LISTEN_RAW);
+ }
+ break;
+ case BOUND:
+ /* Lease is starting to run out, time to enter renewing state */
+ state = RENEWING;
+ change_mode(LISTEN_KERNEL);
+ DEBUG("Entering renew state");
+ /* fall right through */
+ case RENEWING:
+ /* Either set a new T1, or enter REBINDING state */
+ if ((t2 - t1) <= (lease / 14400 + 1)) {
+ /* timed out, enter rebinding state */
+ state = REBINDING;
+ timeout = now + (t2 - t1);
+ 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;
+ }
+ break;
+ case REBINDING:
+ /* Either set a new T2, or enter INIT state */
+ if ((lease - t2) <= (lease / 14400 + 1)) {
+ /* timed out, enter init state */
+ state = INIT_SELECTING;
+ bb_info_msg("Lease lost, entering init state");
+ udhcp_run_script(NULL, "deconfig");
+ timeout = now;
+ packet_num = 0;
+ change_mode(LISTEN_RAW);
+ } else {
+ /* send a request packet */
+ send_renew(xid, 0, requested_ip); /* broadcast */
+
+ t2 = (lease - t2) / 2 + t2;
+ timeout = t2 + start;
+ }
+ break;
+ case RELEASED:
+ /* yah, I know, *you* say it would never happen */
+ timeout = 0x7fffffff;
+ break;
+ }
+ } else if (retval > 0 && listen_mode != LISTEN_NONE && FD_ISSET(fd, &rfds)) {
+ /* a packet is ready, read it */
+
+ if (listen_mode == LISTEN_KERNEL)
+ len = udhcp_get_packet(&packet, fd);
+ else len = get_raw_packet(&packet, fd);
+
+ if (len == -1 && errno != EINTR) {
+ 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("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) {
+ 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) {
+ temp = get_option(&packet, DHCP_SERVER_ID);
+ if (temp) {
+ /* can be misaligned, thus memcpy */
+ memcpy(&server_addr, temp, 4);
+ xid = packet.xid;
+ requested_ip = packet.yiaddr;
+
+ /* enter requesting state */
+ state = REQUESTING;
+ timeout = now;
+ packet_num = 0;
+ } else {
+ bb_error_msg("no server ID in message");
+ }
+ }
+ break;
+ case RENEW_REQUESTED:
+ case REQUESTING:
+ case RENEWING:
+ case REBINDING:
+ if (*message == DHCPACK) {
+ 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 {
+ /* can be misaligned, thus memcpy */
+ memcpy(&lease, temp, 4);
+ lease = ntohl(lease);
+ }
+
+ /* enter bound state */
+ t1 = lease / 2;
+
+ /* little fixed point for n * .875 */
+ t2 = (lease * 0x7) >> 3;
+ temp_addr.s_addr = packet.yiaddr;
+ bb_info_msg("Lease of %s obtained, lease time %ld",
+ inet_ntoa(temp_addr), lease);
+ start = now;
+ timeout = t1 + start;
+ requested_ip = packet.yiaddr;
+ udhcp_run_script(&packet,
+ ((state == RENEWING || state == REBINDING) ? "renew" : "bound"));
+
+ state = BOUND;
+ change_mode(LISTEN_NONE);
+ 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 */
+ bb_info_msg("Received DHCP NAK");
+ udhcp_run_script(&packet, "nak");
+ if (state != REQUESTING)
+ udhcp_run_script(NULL, "deconfig");
+ state = INIT_SELECTING;
+ timeout = now;
+ requested_ip = 0;
+ packet_num = 0;
+ change_mode(LISTEN_RAW);
+ sleep(3); /* avoid excessive network traffic */
+ }
+ break;
+ /* case BOUND, RELEASED: - ignore all packets */
+ }
+ } else if (retval > 0 && (sig = udhcp_sp_read(&rfds))) {
+ switch (sig) {
+ case SIGUSR1:
+ perform_renew();
+ break;
+ case SIGUSR2:
+ perform_release();
+ break;
+ case SIGTERM:
+ 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 */
+ } else {
+ /* An error occured */
+ bb_perror_msg("select");
+ }
+
+ }
+ return 0;
+}