Correcting tag name to be like previous ones1_3_0

1 files changed, 509 insertions, 0 deletions

diff --git a/networking/udhcp/dhcpc.c b/networking/udhcp/dhcpc.c
new file mode 100644
index 0000000..71315ff
--- /dev/null
+++ b/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 unsigned long 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[])
+{
+	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);
+			if (fd < 0) {
+				bb_perror_msg("FATAL: cannot listen on socket");
+				return 0;
+			}
+		}
+		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) {
+						server_addr = *(uint32_t*)temp;
+						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 {
+						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;
+					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;
+}