*
* Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
*/
-
#include <syslog.h>
-
/* Override ENABLE_FEATURE_PIDFILE - ifupdown needs our pidfile to always exist */
#define WANT_PIDFILE 1
#include "common.h"
#include "options.h"
-static int timeout; /* = 0. Must be signed */
-static uint32_t requested_ip; /* = 0 */
-static uint32_t server_addr;
static int sockfd = -1;
-#define LISTEN_NONE 0
+#define LISTEN_NONE 0
#define LISTEN_KERNEL 1
-#define LISTEN_RAW 2
+#define LISTEN_RAW 2
static smallint listen_mode;
+/* initial state: (re)start DHCP negotiation */
+#define INIT_SELECTING 0
+/* discover was sent, DHCPOFFER reply received */
+#define REQUESTING 1
+/* select/renew was sent, DHCPACK reply received */
+#define BOUND 2
+/* half of lease passed, want to renew it by sending unicast renew requests */
+#define RENEWING 3
+/* renew requests were not answered, lease is almost over, send broadcast renew */
+#define REBINDING 4
+/* manually requested renew (SIGUSR1) */
+#define RENEW_REQUESTED 5
+/* release, possibly manually requested (SIGUSR2) */
+#define RELEASED 6
static smallint state;
/* struct client_config_t client_config is in bb_common_bufsiz1 */
/* just a little helper */
static void change_listen_mode(int new_mode)
{
- DEBUG("entering %s listen mode",
- new_mode ? (new_mode == 1 ? "kernel" : "raw") : "none");
+ log1("Entering listen mode: %s",
+ new_mode != LISTEN_NONE
+ ? (new_mode == LISTEN_KERNEL ? "kernel" : "raw")
+ : "none"
+ );
+
+ listen_mode = new_mode;
if (sockfd >= 0) {
close(sockfd);
sockfd = -1;
}
- listen_mode = new_mode;
+ if (new_mode == LISTEN_KERNEL)
+ sockfd = udhcp_listen_socket(/*INADDR_ANY,*/ CLIENT_PORT, client_config.interface);
+ else if (new_mode != LISTEN_NONE)
+ sockfd = udhcp_raw_socket(client_config.ifindex);
+ /* else LISTEN_NONE: sockfd stay closed */
}
/* perform a release */
-static void perform_release(void)
+static void perform_release(uint32_t requested_ip, uint32_t server_addr)
{
char buffer[sizeof("255.255.255.255")];
struct in_addr temp_addr;
change_listen_mode(LISTEN_NONE);
state = RELEASED;
- timeout = INT_MAX;
}
+#if BB_MMU
static void client_background(void)
{
-#if !BB_MMU
- bb_error_msg("cannot background in uclinux (yet)");
-/* ... mainly because udhcpc calls client_background()
- * in _the _middle _of _udhcpc _run_, not at the start!
- * If that will be properly disabled for NOMMU, client_background()
- * will work on NOMMU too */
-#else
bb_daemonize(0);
logmode &= ~LOGMODE_STDIO;
/* rewrite pidfile, as our pid is different now */
write_pidfile(client_config.pidfile);
-#endif
- /* Do not fork again. */
- client_config.foreground = 1;
- client_config.background_if_no_lease = 0;
}
+#endif
static uint8_t* alloc_dhcp_option(int code, const char *str, int extra)
int udhcpc_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
-int udhcpc_main(int argc ATTRIBUTE_UNUSED, char **argv)
+int udhcpc_main(int argc UNUSED_PARAM, char **argv)
{
uint8_t *temp, *message;
char *str_c, *str_V, *str_h, *str_F, *str_r;
- USE_FEATURE_UDHCP_PORT(char *str_P;)
+ IF_FEATURE_UDHCP_PORT(char *str_P;)
llist_t *list_O = NULL;
-#if ENABLE_FEATURE_UDHCPC_ARPING
- char *str_W;
-#endif
int tryagain_timeout = 20;
int discover_timeout = 3;
int discover_retries = 3;
+ uint32_t server_addr = server_addr; /* for compiler */
+ uint32_t requested_ip = 0;
uint32_t xid = 0;
uint32_t lease_seconds = 0; /* can be given as 32-bit quantity */
int packet_num;
- /* t1, t2... what a wonderful names... */
- unsigned t1 = t1; /* for gcc */
- unsigned t2 = t2;
- unsigned timestamp_got_lease = timestamp_got_lease;
+ int timeout; /* must be signed */
+ unsigned already_waited_sec;
unsigned opt;
int max_fd;
int retval;
- int len;
struct timeval tv;
- struct in_addr temp_addr;
- struct dhcpMessage packet;
+ struct dhcp_packet packet;
fd_set rfds;
- 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,
- OPT_S = 1 << 18,
- OPT_A = 1 << 19,
-#if ENABLE_FEATURE_UDHCPC_ARPING
- OPT_a = 1 << 20,
- OPT_W = 1 << 21,
-#endif
- OPT_P = 1 << 22,
- };
-#if ENABLE_GETOPT_LONG
+#if ENABLE_LONG_OPTS
static const char udhcpc_longopts[] ALIGN1 =
"clientid\0" Required_argument "c"
"clientid-none\0" No_argument "C"
"vendorclass\0" Required_argument "V"
- "foreground\0" No_argument "f"
- "background\0" No_argument "b"
"hostname\0" Required_argument "H"
"fqdn\0" Required_argument "F"
"interface\0" Required_argument "i"
"retries\0" Required_argument "t"
"tryagain\0" Required_argument "A"
"syslog\0" No_argument "S"
-#if ENABLE_FEATURE_UDHCPC_ARPING
- "arping\0" No_argument "a"
-#endif
"request-option\0" Required_argument "O"
-#if ENABLE_FEATURE_UDHCP_PORT
- "client-port\0" Required_argument "P"
-#endif
+ "no-default-options\0" No_argument "o"
+ "foreground\0" No_argument "f"
+ "background\0" No_argument "b"
+ IF_FEATURE_UDHCPC_ARPING("arping\0" No_argument "a")
+ IF_FEATURE_UDHCP_PORT("client-port\0" Required_argument "P")
;
#endif
+ enum {
+ OPT_c = 1 << 0,
+ OPT_C = 1 << 1,
+ OPT_V = 1 << 2,
+ OPT_H = 1 << 3,
+ OPT_h = 1 << 4,
+ OPT_F = 1 << 5,
+ OPT_i = 1 << 6,
+ OPT_n = 1 << 7,
+ OPT_p = 1 << 8,
+ OPT_q = 1 << 9,
+ OPT_R = 1 << 10,
+ OPT_r = 1 << 11,
+ OPT_s = 1 << 12,
+ OPT_T = 1 << 13,
+ OPT_t = 1 << 14,
+ OPT_S = 1 << 15,
+ OPT_A = 1 << 16,
+ OPT_O = 1 << 17,
+ OPT_o = 1 << 18,
+ OPT_f = 1 << 19,
+/* The rest has variable bit positions, need to be clever */
+ OPTBIT_f = 19,
+ USE_FOR_MMU( OPTBIT_b,)
+ IF_FEATURE_UDHCPC_ARPING(OPTBIT_a,)
+ IF_FEATURE_UDHCP_PORT( OPTBIT_P,)
+ USE_FOR_MMU( OPT_b = 1 << OPTBIT_b,)
+ IF_FEATURE_UDHCPC_ARPING(OPT_a = 1 << OPTBIT_a,)
+ IF_FEATURE_UDHCP_PORT( OPT_P = 1 << OPTBIT_P,)
+ };
+
/* Default options. */
-#if ENABLE_FEATURE_UDHCP_PORT
- SERVER_PORT = 67;
- CLIENT_PORT = 68;
-#endif
+ IF_FEATURE_UDHCP_PORT(SERVER_PORT = 67;)
+ IF_FEATURE_UDHCP_PORT(CLIENT_PORT = 68;)
client_config.interface = "eth0";
client_config.script = DEFAULT_SCRIPT;
/* Parse command line */
/* Cc: mutually exclusive; O: list; -T,-t,-A take numeric param */
- opt_complementary = "c--C:C--c:O::T+:t+:A+";
-#if ENABLE_GETOPT_LONG
- applet_long_options = udhcpc_longopts;
+ opt_complementary = "c--C:C--c:O::T+:t+:A+"
+#if defined CONFIG_UDHCP_DEBUG && CONFIG_UDHCP_DEBUG >= 1
+ ":vv"
#endif
- opt = getopt32(argv, "c:CV:fbH:h:F:i:np:qRr:s:T:t:vSA:"
- USE_FEATURE_UDHCPC_ARPING("aW:")
- USE_FEATURE_UDHCP_PORT("P:")
- "O:"
+ ;
+ IF_LONG_OPTS(applet_long_options = udhcpc_longopts;)
+ opt = getopt32(argv, "c:CV:H:h:F:i:np:qRr:s:T:t:SA:O:of"
+ USE_FOR_MMU("b")
+ IF_FEATURE_UDHCPC_ARPING("a")
+ IF_FEATURE_UDHCP_PORT("P:")
+ "v"
, &str_c, &str_V, &str_h, &str_h, &str_F
- , &client_config.interface, &client_config.pidfile, &str_r
- , &client_config.script
- , &discover_timeout, &discover_retries, &tryagain_timeout
- USE_FEATURE_UDHCPC_ARPING(, &str_W)
- USE_FEATURE_UDHCP_PORT(, &str_P)
+ , &client_config.interface, &client_config.pidfile, &str_r /* i,p */
+ , &client_config.script /* s */
+ , &discover_timeout, &discover_retries, &tryagain_timeout /* T,t,A */
, &list_O
+ IF_FEATURE_UDHCP_PORT(, &str_P)
+#if defined CONFIG_UDHCP_DEBUG && CONFIG_UDHCP_DEBUG >= 1
+ , &dhcp_verbose
+#endif
);
-
if (opt & OPT_c)
client_config.clientid = alloc_dhcp_option(DHCP_CLIENT_ID, str_c, 0);
- //if (opt & OPT_C)
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|OPT_H))
client_config.hostname = alloc_dhcp_option(DHCP_HOST_NAME, str_h, 0);
if (opt & OPT_F) {
/* 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"
+ E: 1 => Name data is DNS format, i.e. <4>host<6>domain<3>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) discover_timeout = xatoi_u(str_T);
- // if (opt & OPT_t) discover_retries = xatoi_u(str_t);
- // if (opt & OPT_A) tryagain_timeout = xatoi_u(str_A);
- if (opt & OPT_v) {
- puts("version "BB_VER);
- return 0;
- }
- if (opt & OPT_S) {
- openlog(applet_name, LOG_PID, LOG_LOCAL0);
- logmode |= LOGMODE_SYSLOG;
- }
#if ENABLE_FEATURE_UDHCP_PORT
if (opt & OPT_P) {
CLIENT_PORT = xatou16(str_P);
SERVER_PORT = CLIENT_PORT - 1;
}
#endif
+ if (opt & OPT_o)
+ client_config.no_default_options = 1;
while (list_O) {
- int n = index_in_strings(dhcp_option_strings, list_O->data);
+ char *optstr = llist_pop(&list_O);
+ int n = index_in_strings(dhcp_option_strings, optstr);
if (n < 0)
- bb_error_msg_and_die("unknown option '%s'", list_O->data);
+ bb_error_msg_and_die("unknown option '%s'", optstr);
n = dhcp_options[n].code;
client_config.opt_mask[n >> 3] |= 1 << (n & 7);
- list_O = list_O->link;
}
- if (read_interface(client_config.interface, &client_config.ifindex,
- NULL, client_config.arp))
+ if (udhcp_read_interface(client_config.interface,
+ &client_config.ifindex,
+ NULL,
+ client_config.client_mac)
+ ) {
return 1;
+ }
+
+#if !BB_MMU
+ /* on NOMMU reexec (i.e., background) early */
+ if (!(opt & OPT_f)) {
+ bb_daemonize_or_rexec(0 /* flags */, argv);
+ logmode = LOGMODE_NONE;
+ }
+#endif
+ if (opt & OPT_S) {
+ openlog(applet_name, LOG_PID, LOG_DAEMON);
+ logmode |= LOGMODE_SYSLOG;
+ }
/* Make sure fd 0,1,2 are open */
bb_sanitize_stdio();
/* Create pidfile */
write_pidfile(client_config.pidfile);
- /* if (!..) bb_perror_msg("cannot create pidfile %s", pidfile); */
- /* Goes to stdout and possibly syslog */
+ /* Goes to stdout (unless NOMMU) and possibly syslog */
bb_info_msg("%s (v"BB_VER") started", applet_name);
- /* if not set, and not suppressed, setup the default client ID */
+ /* If not set, and not suppressed, set up the default client ID */
if (!client_config.clientid && !(opt & OPT_C)) {
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);
+ memcpy(client_config.clientid + OPT_DATA+1, client_config.client_mac, 6);
}
if (!client_config.vendorclass)
client_config.vendorclass = alloc_dhcp_option(DHCP_VENDOR, "udhcp "BB_VER, 0);
- /* setup the signal pipe */
+ /* Set up the signal pipe */
udhcp_sp_setup();
state = INIT_SELECTING;
udhcp_run_script(NULL, "deconfig");
change_listen_mode(LISTEN_RAW);
packet_num = 0;
+ timeout = 0;
+ already_waited_sec = 0;
/* Main event loop. select() waits on signal pipe and possibly
* on sockfd.
* "continue" statements in code below jump to the top of the loop.
*/
for (;;) {
- tv.tv_sec = timeout;
- tv.tv_usec = 0;
+ /* silence "uninitialized!" warning */
+ unsigned timestamp_before_wait = timestamp_before_wait;
+
+ //bb_error_msg("sockfd:%d, listen_mode:%d", sockfd, listen_mode);
+
+ /* Was opening raw or udp socket here
+ * if (listen_mode != LISTEN_NONE && sockfd < 0),
+ * but on fast network renew responses return faster
+ * than we open sockets. Thus this code is moved
+ * to change_listen_mode(). Thus we open listen socket
+ * BEFORE we send renew request (see "case BOUND:"). */
- if (listen_mode != LISTEN_NONE && sockfd < 0) {
- if (listen_mode == LISTEN_KERNEL)
- sockfd = listen_socket(/*INADDR_ANY,*/ CLIENT_PORT, client_config.interface);
- else
- sockfd = raw_socket(client_config.ifindex);
- }
max_fd = udhcp_sp_fd_set(&rfds, sockfd);
+ tv.tv_sec = timeout - already_waited_sec;
+ tv.tv_usec = 0;
retval = 0; /* If we already timed out, fall through, else... */
- if (tv.tv_sec > 0) {
- DEBUG("Waiting on select...");
+ if ((int)tv.tv_sec > 0) {
+ timestamp_before_wait = (unsigned)monotonic_sec();
+ log1("Waiting on select...");
retval = select(max_fd + 1, &rfds, NULL, NULL, &tv);
- }
-
- if (retval < 0) {
- /* EINTR? signal was caught, don't panic */
- if (errno != EINTR) {
+ if (retval < 0) {
+ /* EINTR? A signal was caught, don't panic */
+ if (errno == EINTR) {
+ already_waited_sec += (unsigned)monotonic_sec() - timestamp_before_wait;
+ continue;
+ }
/* Else: an error occured, panic! */
bb_perror_msg_and_die("select");
}
- continue;
}
/* If timeout dropped to zero, time to become active:
* resend discover/renew/whatever
*/
if (retval == 0) {
+ /* We will restart the wait in any case */
+ already_waited_sec = 0;
+
switch (state) {
case INIT_SELECTING:
if (packet_num < discover_retries) {
if (packet_num == 0)
xid = random_xid();
-
- /* send discover packet */
- send_discover(xid, requested_ip); /* broadcast */
-
+ /* broadcast */
+ send_discover(xid, requested_ip);
timeout = discover_timeout;
packet_num++;
continue;
}
+ leasefail:
udhcp_run_script(NULL, "leasefail");
- if (client_config.background_if_no_lease) {
+#if BB_MMU /* -b is not supported on NOMMU */
+ if (opt & OPT_b) { /* background if no lease */
bb_info_msg("No lease, forking to background");
client_background();
- } else if (client_config.abort_if_no_lease) {
+ /* do not background again! */
+ opt = ((opt & ~OPT_b) | OPT_f);
+ } else
+#endif
+ if (opt & OPT_n) { /* abort if no lease */
bb_info_msg("No lease, failing");
retval = 1;
goto ret;
}
- /* wait to try again */
+ /* wait before trying again */
timeout = tryagain_timeout;
packet_num = 0;
continue;
- case RENEW_REQUESTED:
case REQUESTING:
if (packet_num < discover_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 = ((packet_num == 2) ? 10 : 2);
+ /* send broadcast select packet */
+ send_select(xid, server_addr, requested_ip);
+ timeout = discover_timeout;
packet_num++;
continue;
}
- /* timed out, go back to init state */
- if (state == RENEW_REQUESTED)
- udhcp_run_script(NULL, "deconfig");
+ /* Timed out, go back to init state.
+ * "discover...select...discover..." loops
+ * were seen in the wild. Treat them similarly
+ * to "no response to discover" case */
change_listen_mode(LISTEN_RAW);
state = INIT_SELECTING;
- timeout = 0;
- packet_num = 0;
- continue;
+ goto leasefail;
case BOUND:
- /* Lease is starting to run out, time to enter renewing state */
- change_listen_mode(LISTEN_KERNEL);
- DEBUG("Entering renew state");
+ /* 1/2 lease passed, enter renewing state */
state = RENEWING;
+ change_listen_mode(LISTEN_KERNEL);
+ log1("Entering renew state");
/* fall right through */
+ case RENEW_REQUESTED: /* manual (SIGUSR1) renew */
+ case_RENEW_REQUESTED:
case RENEWING:
- /* Either set a new T1, or enter REBINDING state */
- if ((t2 - t1) > (lease_seconds / (4*60*60) + 1)) {
- /* send a request packet */
- send_renew(xid, server_addr, requested_ip); /* unicast */
- t1 += (t2 - t1) / 2;
- timeout = t1 - ((int)monotonic_sec() - timestamp_got_lease);
+ if (timeout > 60) {
+ /* send an unicast renew request */
+ /* Sometimes observed to fail (EADDRNOTAVAIL) to bind
+ * a new UDP socket for sending inside send_renew.
+ * I hazard to guess existing listening socket
+ * is somehow conflicting with it, but why is it
+ * not deterministic then?! Strange.
+ * Anyway, it does recover by eventually failing through
+ * into INIT_SELECTING state.
+ */
+ send_renew(xid, server_addr, requested_ip);
+ timeout >>= 1;
continue;
}
/* Timed out, enter rebinding state */
- DEBUG("Entering rebinding state");
+ log1("Entering rebinding state");
state = REBINDING;
- timeout = (t2 - t1);
- continue;
+ /* fall right through */
case REBINDING:
+ /* Switch to bcast receive */
+ change_listen_mode(LISTEN_RAW);
/* Lease is *really* about to run out,
* try to find DHCP server using broadcast */
- if ((lease_seconds - t2) > (lease_seconds / (4*60*60) + 1)) {
- /* send a request packet */
- send_renew(xid, 0, requested_ip); /* broadcast */
- t2 += (lease_seconds - t2) / 2;
- timeout = t2 - ((int)monotonic_sec() - timestamp_got_lease);
+ if (timeout > 0) {
+ /* send a broadcast renew request */
+ send_renew(xid, 0 /*INADDR_ANY*/, requested_ip);
+ timeout >>= 1;
continue;
}
/* Timed out, enter init state */
bb_info_msg("Lease lost, entering init state");
udhcp_run_script(NULL, "deconfig");
- change_listen_mode(LISTEN_RAW);
state = INIT_SELECTING;
- timeout = 0;
+ /*timeout = 0; - already is */
packet_num = 0;
continue;
/* case RELEASED: */
/* yah, I know, *you* say it would never happen */
timeout = INT_MAX;
continue; /* back to main loop */
+ } /* if select timed out */
+
+ /* select() didn't timeout, something happened */
+
+ /* Is it a signal? */
+ /* note: udhcp_sp_read checks FD_ISSET before reading */
+ switch (udhcp_sp_read(&rfds)) {
+ case SIGUSR1:
+ perform_renew();
+ if (state == RENEW_REQUESTED)
+ goto case_RENEW_REQUESTED;
+ /* Start things over */
+ packet_num = 0;
+ /* Kill any timeouts, user wants this to hurry along */
+ timeout = 0;
+ continue;
+ case SIGUSR2:
+ perform_release(requested_ip, server_addr);
+ timeout = INT_MAX;
+ continue;
+ case SIGTERM:
+ bb_info_msg("Received SIGTERM");
+ if (opt & OPT_R) /* release on quit */
+ perform_release(requested_ip, server_addr);
+ goto ret0;
}
- /* select() didn't timeout, something did happen. */
- /* Is is a packet? */
- if (listen_mode != LISTEN_NONE && FD_ISSET(sockfd, &rfds)) {
- /* A packet is ready, read it */
+ /* Is it a packet? */
+ if (listen_mode == LISTEN_NONE || !FD_ISSET(sockfd, &rfds))
+ continue; /* no */
+
+ {
+ int len;
+ /* A packet is ready, read it */
if (listen_mode == LISTEN_KERNEL)
- len = udhcp_recv_packet(&packet, sockfd);
+ len = udhcp_recv_kernel_packet(&packet, sockfd);
else
- len = get_raw_packet(&packet, sockfd);
-
- if (len == -1) { /* error is severe, reopen socket */
- DEBUG("error on read, %s, reopening socket", strerror(errno));
+ len = udhcp_recv_raw_packet(&packet, sockfd);
+ if (len == -1) {
+ /* Error is severe, reopen socket */
+ bb_info_msg("Read error: %s, reopening socket", strerror(errno));
+ sleep(discover_timeout); /* 3 seconds by default */
change_listen_mode(listen_mode); /* just close and reopen */
}
- if (len < 0) continue;
-
- if (packet.xid != xid) {
- DEBUG("Ignoring XID %x (our xid is %x)",
- (unsigned)packet.xid, (unsigned)xid);
+ /* If this packet will turn out to be unrelated/bogus,
+ * we will go back and wait for next one.
+ * Be sure timeout is properly decreased. */
+ already_waited_sec += (unsigned)monotonic_sec() - timestamp_before_wait;
+ if (len < 0)
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 (packet.xid != xid) {
+ log1("xid %x (our is %x), ignoring packet",
+ (unsigned)packet.xid, (unsigned)xid);
+ continue;
+ }
- message = get_option(&packet, DHCP_MESSAGE_TYPE);
- if (message == NULL) {
- bb_error_msg("cannot get message type from packet - ignoring");
- continue;
- }
+ /* Ignore packets that aren't for us */
+ if (packet.hlen != 6
+ || memcmp(packet.chaddr, client_config.client_mac, 6)
+ ) {
+//FIXME: need to also check that last 10 bytes are zero
+ log1("chaddr does not match, ignoring packet"); // log2?
+ continue;
+ }
- switch (state) {
- case INIT_SELECTING:
- /* Must be a DHCPOFFER to one of our xid's */
- if (*message == DHCPOFFER) {
- /* TODO: why we don't just fetch server's IP from IP header? */
- temp = get_option(&packet, DHCP_SERVER_ID);
- if (!temp) {
- bb_error_msg("no server ID in message");
- continue;
- /* still selecting - this server looks bad */
- }
- /* can be misaligned, thus memcpy */
- memcpy(&server_addr, temp, 4);
- xid = packet.xid;
- requested_ip = packet.yiaddr;
-
- /* enter requesting state */
- state = REQUESTING;
- timeout = 0;
- packet_num = 0;
+ message = get_option(&packet, DHCP_MESSAGE_TYPE);
+ if (message == NULL) {
+ bb_error_msg("no message type option, ignoring packet");
+ continue;
+ }
+
+ switch (state) {
+ case INIT_SELECTING:
+ /* Must be a DHCPOFFER to one of our xid's */
+ if (*message == DHCPOFFER) {
+ /* TODO: why we don't just fetch server's IP from IP header? */
+ temp = get_option(&packet, DHCP_SERVER_ID);
+ if (!temp) {
+ bb_error_msg("no server ID in message");
+ continue;
+ /* still selecting - this server looks bad */
+ }
+ /* it IS unaligned sometimes, don't "optimize" */
+ move_from_unaligned32(server_addr, temp);
+ xid = packet.xid;
+ requested_ip = packet.yiaddr;
+
+ /* enter requesting state */
+ state = REQUESTING;
+ timeout = 0;
+ packet_num = 0;
+ already_waited_sec = 0;
+ }
+ continue;
+ case REQUESTING:
+ case RENEWING:
+ case RENEW_REQUESTED:
+ 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_seconds = 60 * 60;
+ } else {
+ /* it IS unaligned sometimes, don't "optimize" */
+ move_from_unaligned32(lease_seconds, temp);
+ lease_seconds = ntohl(lease_seconds);
+ lease_seconds &= 0x0fffffff; /* paranoia: must not be prone to overflows */
+ if (lease_seconds < 10) /* and not too small */
+ lease_seconds = 10;
}
- continue;
- 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_seconds = 60 * 60;
- } else {
- /* can be misaligned, thus memcpy */
- memcpy(&lease_seconds, temp, 4);
- lease_seconds = ntohl(lease_seconds);
- }
#if ENABLE_FEATURE_UDHCPC_ARPING
- if (opt & OPT_a) {
- if (!arpping(packet.yiaddr,
- (uint32_t) 0,
- client_config.arp,
- client_config.interface)
- ) {
- bb_info_msg("offered address is in use "
- "(got ARP reply), declining");
- send_decline(xid, server_addr, packet.yiaddr);
-
- if (state != REQUESTING)
- udhcp_run_script(NULL, "deconfig");
- change_listen_mode(LISTEN_RAW);
- state = INIT_SELECTING;
- requested_ip = 0;
- timeout = tryagain_timeout;
- packet_num = 0;
- continue; /* back to main loop */
- }
+ if (opt & OPT_a) {
+/* RFC 2131 3.1 paragraph 5:
+ * "The client receives the DHCPACK message with configuration
+ * parameters. The client SHOULD perform a final check on the
+ * parameters (e.g., ARP for allocated network address), and notes
+ * the duration of the lease specified in the DHCPACK message. At this
+ * point, the client is configured. If the client detects that the
+ * address is already in use (e.g., through the use of ARP),
+ * the client MUST send a DHCPDECLINE message to the server and restarts
+ * the configuration process..." */
+ if (!arpping(packet.yiaddr,
+ NULL,
+ (uint32_t) 0,
+ client_config.client_mac,
+ client_config.interface)
+ ) {
+ bb_info_msg("Offered address is in use "
+ "(got ARP reply), declining");
+ send_decline(xid, server_addr, packet.yiaddr);
+
+ if (state != REQUESTING)
+ udhcp_run_script(NULL, "deconfig");
+ change_listen_mode(LISTEN_RAW);
+ state = INIT_SELECTING;
+ requested_ip = 0;
+ timeout = tryagain_timeout;
+ packet_num = 0;
+ already_waited_sec = 0;
+ continue; /* back to main loop */
}
+ }
#endif
- /* enter bound state */
- t1 = lease_seconds / 2;
-
- /* little fixed point for n * .875 */
- t2 = (lease_seconds * 7) >> 3;
+ /* enter bound state */
+ timeout = lease_seconds / 2;
+ {
+ struct in_addr temp_addr;
temp_addr.s_addr = packet.yiaddr;
bb_info_msg("Lease of %s obtained, lease time %u",
inet_ntoa(temp_addr), (unsigned)lease_seconds);
- timestamp_got_lease = monotonic_sec();
- timeout = t1;
- requested_ip = packet.yiaddr;
- udhcp_run_script(&packet,
- ((state == RENEWING || state == REBINDING) ? "renew" : "bound"));
-
- state = BOUND;
- change_listen_mode(LISTEN_NONE);
- if (client_config.quit_after_lease) {
- if (client_config.release_on_quit)
- perform_release();
- goto ret0;
- }
- if (!client_config.foreground)
- client_background();
-
- continue; /* back to main loop */
}
- 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");
- change_listen_mode(LISTEN_RAW);
- sleep(3); /* avoid excessive network traffic */
- state = INIT_SELECTING;
- requested_ip = 0;
- timeout = 0;
- packet_num = 0;
+ requested_ip = packet.yiaddr;
+ udhcp_run_script(&packet, state == REQUESTING ? "bound" : "renew");
+
+ state = BOUND;
+ change_listen_mode(LISTEN_NONE);
+ if (opt & OPT_q) { /* quit after lease */
+ if (opt & OPT_R) /* release on quit */
+ perform_release(requested_ip, server_addr);
+ goto ret0;
}
- continue;
- /* case BOUND, RELEASED: - ignore all packets */
+ /* future renew failures should not exit (JM) */
+ opt &= ~OPT_n;
+#if BB_MMU /* NOMMU case backgrounded earlier */
+ if (!(opt & OPT_f)) {
+ client_background();
+ /* do not background again! */
+ opt = ((opt & ~OPT_b) | OPT_f);
+ }
+#endif
+ already_waited_sec = 0;
+ continue; /* back to main loop */
}
- continue; /* back to main loop */
- }
-
- /* select() didn't timeout, something did happen.
- * But it wasn't a packet. It's a signal pipe then. */
- {
- int signo = udhcp_sp_read(&rfds);
- switch (signo) {
- case SIGUSR1:
- perform_renew();
- /* start things over */
- packet_num = 0;
- /* Kill any timeouts because the user wants this to hurry along */
+ 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");
+ change_listen_mode(LISTEN_RAW);
+ sleep(3); /* avoid excessive network traffic */
+ state = INIT_SELECTING;
+ requested_ip = 0;
timeout = 0;
- break;
- case SIGUSR2:
- perform_release();
- break;
- case SIGTERM:
- bb_info_msg("Received SIGTERM");
- if (client_config.release_on_quit)
- perform_release();
- goto ret0;
+ packet_num = 0;
+ already_waited_sec = 0;
}
+ continue;
+ /* case BOUND: - ignore all packets */
+ /* case RELEASED: - ignore all packets */
}
+ /* back to main loop */
} /* for (;;) - main loop ends */
ret0:
retval = 0;
ret:
- /*if (client_config.pidfile) - remove_pidfile has it's own check */
+ /*if (client_config.pidfile) - remove_pidfile has its own check */
remove_pidfile(client_config.pidfile);
return retval;
}
projects / oweals / busybox.git / blobdiff