configurable, ~+300 bytes when on.
"and * (run both after creating and before deleting). The commands run in\n" \
"the /dev directory, and use system() which calls /bin/sh.\n\n" \
) \
- "Config file parsing stops on the first matching line. If no config\n"\
- "entry is matched, devices are created with default 0:0 660. (Make\n"\
+ "Config file parsing stops on the first matching line. If no config\n" \
+ "entry is matched, devices are created with default 0:0 660. (Make\n" \
"the last line match .* to override this.)\n\n" \
)
" [-p pidfile] [-r IP] [-s script]"
#define udhcpc_full_usage \
USE_GETOPT_LONG( \
- " -V,--vendorclass=CLASSID Set vendor class identifier" \
- "\n -i,--interface=INTERFACE Interface to use (default: eth0)" \
+ " -V,--vendorclass=CLASSID Vendor class identifier" \
+ "\n -i,--interface=INTERFACE Interface to use (default eth0)" \
"\n -H,-h,--hostname=HOSTNAME Client hostname" \
- "\n -c,--clientid=CLIENTID Set client identifier" \
+ "\n -c,--clientid=CLIENTID Client identifier" \
"\n -C,--clientid-none Suppress default client identifier" \
- "\n -p,--pidfile=file Store process ID of daemon in file" \
+ "\n -p,--pidfile=file Create pidfile" \
"\n -r,--request=IP IP address to request" \
"\n -s,--script=file Run file at dhcp events (default: /usr/share/udhcpc/default.script)" \
- "\n -t,--retries=N Send up to N request packets"\
- "\n -T,--timeout=N Try to get a lease for N seconds (default: 3)"\
- "\n -A,--tryagain=N Wait N seconds (default: 60) after failure"\
+ "\n -t,--retries=N Send up to N request packets" \
+ "\n -T,--timeout=N Try to get a lease for N seconds (default 3)" \
+ "\n -A,--tryagain=N Wait N seconds (default 60) after failure" \
"\n -f,--foreground Run in foreground" \
- "\n -b,--background Background if lease cannot be immediately negotiated" \
+ "\n -b,--background Background if lease is not immediately obtained" \
"\n -S,--syslog Log to syslog too" \
- "\n -n,--now Exit with failure if lease cannot be immediately negotiated" \
+ "\n -n,--now Exit with failure if lease is not immediately obtained" \
"\n -q,--quit Quit after obtaining lease" \
"\n -R,--release Release IP on quit" \
- "\n -v,--version Display version" \
+ USE_FEATURE_UDHCPC_ARPING( \
+ "\n -a,--arping Use arping to validate offered address" \
+ "\n -W,--wait=N Wait N seconds after declining (default 10)" \
+ ) \
) \
SKIP_GETOPT_LONG( \
- " -V CLASSID Set vendor class identifier" \
+ " -V CLASSID Vendor class identifier" \
"\n -i INTERFACE Interface to use (default: eth0)" \
"\n -H,-h HOSTNAME Client hostname" \
- "\n -c CLIENTID Set client identifier" \
+ "\n -c CLIENTID Client identifier" \
"\n -C Suppress default client identifier" \
- "\n -p file Store process ID of daemon in file" \
+ "\n -p file Create pidfile" \
"\n -r IP IP address to request" \
"\n -s file Run file at dhcp events (default: /usr/share/udhcpc/default.script)" \
- "\n -t N Send up to N request packets"\
- "\n -T N Try to get a lease for N seconds (default: 3)"\
- "\n -A N Wait N seconds (default: 60) after failure"\
+ "\n -t N Send up to N request packets" \
+ "\n -T N Try to get a lease for N seconds (default 3)" \
+ "\n -A N Wait N seconds (default 60) after failure" \
"\n -f Run in foreground" \
- "\n -b Background if lease cannot be immediately negotiated" \
+ "\n -b Background if lease is not immediately obtained" \
"\n -S Log to syslog too" \
- "\n -n Exit with failure if lease cannot be immediately negotiated" \
+ "\n -n Exit with failure if lease is not immediately obtained" \
"\n -q Quit after obtaining lease" \
"\n -R Release IP on quit" \
- "\n -v Display version" \
+ USE_FEATURE_UDHCPC_ARPING( \
+ "\n -a Use arping to validate offered address" \
+ "\n -W N Wait N seconds after declining (default 10)" \
+ ) \
)
#define udhcpd_trivial_usage \
See http://udhcp.busybox.net for further details.
+config FEATURE_UDHCPC_ARPING
+ bool "Ask udhcpc to verify that the offered address is free, using arpping"
+ default y
+ depends on APP_UDHCPC
+ help
+ If selected, udhcpc will use arpping to make sure the offered address
+ is really available. The client will DHCPDECLINE the offer if the
+ address is in use, and restart the discover process.
+
+
config FEATURE_UDHCP_DEBUG
bool "Compile udhcp with noisy debugging messages"
default n
signalpipe.o socket.o
lib-$(CONFIG_APP_UDHCPD) += common.o options.o packet.o \
signalpipe.o socket.o
+
lib-$(CONFIG_APP_UDHCPC) += dhcpc.o clientpacket.o clientsocket.o \
script.o
+
+UDHCPC_NEEDS_ARPING-$(CONFIG_FEATURE_UDHCPC_ARPING) = y
+lib-$(UDHCPC_NEEDS_ARPING) += arpping.o
+
lib-$(CONFIG_APP_UDHCPD) += dhcpd.o arpping.o files.o leases.o \
serverpacket.o static_leases.o
+
lib-$(CONFIG_APP_DUMPLEASES) += dumpleases.o
lib-$(CONFIG_APP_DHCPRELAY) += dhcprelay.o
lib-$(CONFIG_FEATURE_RFC3397) += domain_codec.o
uint8_t pad[18]; /* 2a pad for min. ethernet payload (60 bytes) */
} ATTRIBUTE_PACKED;
+enum {
+ ARP_MSG_SIZE = 0x2a
+};
+
/* Returns 1 if no reply received */
int arpping(uint32_t test_ip, uint32_t from_ip, uint8_t *from_mac, const char *interface)
{
- int timeout_ms = 2000;
+ int timeout_ms;
struct pollfd pfd[1];
#define s (pfd[0].fd) /* socket */
int rv = 1; /* "no reply received" yet */
}
if (setsockopt_broadcast(s) == -1) {
- bb_perror_msg("cannot setsocketopt on raw socket");
+ bb_perror_msg("cannot enable bcast on raw socket");
goto ret;
}
arp.operation = htons(ARPOP_REQUEST); /* ARP op code */
memcpy(arp.sHaddr, from_mac, 6); /* source hardware address */
memcpy(arp.sInaddr, &from_ip, sizeof(from_ip)); /* source IP address */
- /* tHaddr */ /* target hardware address */
+ /* tHaddr is zero-fiiled */ /* target hardware address */
memcpy(arp.tInaddr, &test_ip, sizeof(test_ip)); /* target IP address */
memset(&addr, 0, sizeof(addr));
safe_strncpy(addr.sa_data, interface, sizeof(addr.sa_data));
- if (sendto(s, &arp, sizeof(arp), 0, &addr, sizeof(addr)) < 0)
+ if (sendto(s, &arp, sizeof(arp), 0, &addr, sizeof(addr)) < 0) {
+ // TODO: error message? caller didn't expect us to fail,
+ // just returning 1 "no reply received" misleads it.
goto ret;
+ }
/* wait for arp reply, and check it */
+ timeout_ms = 2000;
do {
int r;
unsigned prevTime = monotonic_us();
pfd[0].events = POLLIN;
r = safe_poll(pfd, 1, timeout_ms);
- if (r < 0) {
+ if (r < 0)
break;
- } else if (r) {
- if (read(s, &arp, sizeof(arp)) < 0)
+ if (r) {
+ r = read(s, &arp, sizeof(arp));
+ if (r < 0)
break;
- if (arp.operation == htons(ARPOP_REPLY)
- && memcmp(arp.tHaddr, from_mac, 6) == 0
+ if (r >= ARP_MSG_SIZE
+ && arp.operation == htons(ARPOP_REPLY)
+ /* don't check it: Linux doesn't return proper tHaddr (fixed in 2.6.24?) */
+ /* && memcmp(arp.tHaddr, from_mac, 6) == 0 */
&& *((uint32_t *) arp.sInaddr) == test_ip
) {
rv = 0;
}
+#if ENABLE_FEATURE_UDHCPC_ARPING
+/* Unicast a DHCP decline message */
+int send_decline(uint32_t xid, uint32_t server)
+{
+ struct dhcpMessage packet;
+
+ init_packet(&packet, DHCPDECLINE);
+ packet.xid = xid;
+ add_requests(&packet);
+
+ bb_info_msg("Sending decline...");
+
+ return udhcp_raw_packet(&packet, INADDR_ANY, CLIENT_PORT, INADDR_BROADCAST,
+ SERVER_PORT, MAC_BCAST_ADDR, client_config.ifindex);
+}
+#endif
/* Broadcast a DHCP discover packet to the network, with an optionally requested IP */
int send_discover(uint32_t xid, uint32_t requested)
void udhcp_sp_setup(void);
int udhcp_sp_fd_set(fd_set *rfds, int extra_fd);
-int udhcp_sp_read(fd_set *rfds);
+int udhcp_sp_read(const fd_set *rfds);
int raw_socket(int ifindex);
int read_interface(const char *interface, int *ifindex, uint32_t *addr, uint8_t *arp);
int listen_socket(/*uint32_t ip,*/ int port, const char *inf);
{
uint8_t *temp, *message;
char *str_c, *str_V, *str_h, *str_F, *str_r, *str_T, *str_A, *str_t;
+ int tryagain_timeout = 60;
+ int discover_timeout = 3;
+ int discover_retries = 3;
+#if ENABLE_FEATURE_UDHCPC_ARPING
+ int decline_wait = 10;
+ char *str_W;
+#endif
uint32_t xid = 0;
uint32_t lease = 0; /* can be given as 32-bit quantity */
unsigned t1 = 0, t2 = 0; /* what a wonderful names */
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
};
#if ENABLE_GETOPT_LONG
static const char udhcpc_longopts[] ALIGN1 =
"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"
+ "wait\0" Required_argument "W"
+#endif
;
#endif
/* Default options. */
client_config.interface = "eth0";
client_config.script = DEFAULT_SCRIPT;
- client_config.retries = 3;
- client_config.timeout = 3;
- client_config.tryagain = 60;
/* Parse command line */
opt_complementary = "c--C:C--c" // mutually exclusive
#if ENABLE_GETOPT_LONG
applet_long_options = udhcpc_longopts;
#endif
- opt = getopt32(argv, "c:CV:fbH:h:F:i:np:qRr:s:T:t:vSA:",
- &str_c, &str_V, &str_h, &str_h, &str_F,
+ opt = getopt32(argv, "c:CV:fbH:h:F:i:np:qRr:s:T:t:vSA:"
+ USE_FEATURE_UDHCPC_ARPING("aW:")
+ , &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, &str_A
+ USE_FEATURE_UDHCPC_ARPING(, &str_W)
);
if (opt & OPT_c)
requested_ip = inet_addr(str_r);
// if (opt & OPT_s) client_config.script = ...
if (opt & OPT_T)
- client_config.timeout = xatoi_u(str_T);
+ discover_timeout = xatoi_u(str_T);
if (opt & OPT_t)
- client_config.retries = xatoi_u(str_t);
+ discover_retries = xatoi_u(str_t);
if (opt & OPT_A)
- client_config.tryagain = xatoi_u(str_A);
+ tryagain_timeout = xatoi_u(str_A);
if (opt & OPT_v) {
puts("version "BB_VER);
return 0;
logmode |= LOGMODE_SYSLOG;
}
+#if ENABLE_FEATURE_UDHCPC_ARPING
+ if (opt & OPT_W)
+ decline_wait = xatou_range(str_W, 10, INT_MAX);
+#endif
+
if (read_interface(client_config.interface, &client_config.ifindex,
NULL, client_config.arp))
return 1;
/* timeout dropped to zero */
switch (state) {
case INIT_SELECTING:
- if (packet_num < client_config.retries) {
+ if (packet_num < discover_retries) {
if (packet_num == 0)
xid = random_xid();
/* send discover packet */
send_discover(xid, requested_ip); /* broadcast */
- timeout = now + client_config.timeout;
+ timeout = now + discover_timeout;
packet_num++;
} else {
udhcp_run_script(NULL, "leasefail");
}
/* wait to try again */
packet_num = 0;
- timeout = now + client_config.tryagain;
+ timeout = now + tryagain_timeout;
}
break;
case RENEW_REQUESTED:
case REQUESTING:
- if (packet_num < client_config.retries) {
+ if (packet_num < discover_retries) {
/* send request packet */
if (state == RENEW_REQUESTED)
send_renew(xid, server_addr, requested_ip); /* unicast */
lease = ntohl(lease);
}
+#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,"
+ " declining");
+ send_decline(xid, server_addr);
+
+ if (state != REQUESTING)
+ udhcp_run_script(NULL, "deconfig");
+ state = INIT_SELECTING;
+ requested_ip = 0;
+ packet_num = 0;
+ change_mode(LISTEN_RAW);
+ timeout = now + decline_wait;
+ break;
+ }
+ }
+#endif
/* enter bound state */
t1 = lease / 2;
/* vi: set sw=4 ts=4: */
/* dhcpc.h */
+
#ifndef _DHCPC_H
#define _DHCPC_H
uint8_t *hostname; /* Optional hostname to use */
uint8_t *fqdn; /* Optional fully qualified domain name to use */
int ifindex; /* Index number of the interface to use */
- int retries; /* Max number of request packets */
- int timeout; /* Number of seconds to try to get a lease */
- int tryagain; /* Number of seconds to try to get a lease */
uint8_t arp[6]; /* Our arp address */
};
uint32_t random_xid(void);
int send_discover(uint32_t xid, uint32_t requested);
int send_selecting(uint32_t xid, uint32_t server, uint32_t requested);
+#if ENABLE_FEATURE_UDHCPC_ARPING
+int send_decline(uint32_t xid, uint32_t server);
+#endif
int send_renew(uint32_t xid, uint32_t server, uint32_t ciaddr);
int send_renew(uint32_t xid, uint32_t server, uint32_t ciaddr);
int send_release(uint32_t server, uint32_t ciaddr);
/* Read a signal from the signal pipe. Returns 0 if there is
* no signal, -1 on error (and sets errno appropriately), and
* your signal on success */
-int udhcp_sp_read(fd_set *rfds)
+int udhcp_sp_read(const fd_set *rfds)
{
unsigned char sig;
projects / oweals / busybox.git / commitdiff