/* Initialize the packet with the proper defaults */
static void init_packet(struct dhcp_packet *packet, char type)
{
+ /* Fill in: op, htype, hlen, cookie fields; message type option: */
udhcp_init_header(packet, type);
+
+ packet->xid = random_xid();
+
memcpy(packet->chaddr, client_config.client_mac, 6);
if (client_config.clientid)
udhcp_add_binary_option(packet, client_config.clientid);
+}
+
+static void add_client_options(struct dhcp_packet *packet)
+{
+ uint8_t c;
+ int i, end, len;
+
+ udhcp_add_simple_option(packet, DHCP_MAX_SIZE, htons(IP_UDP_DHCP_SIZE));
if (client_config.hostname)
udhcp_add_binary_option(packet, client_config.hostname);
if (client_config.fqdn)
udhcp_add_binary_option(packet, client_config.fqdn);
- if (type != DHCPDECLINE
- && type != DHCPRELEASE
- && client_config.vendorclass
- ) {
+ if (client_config.vendorclass)
udhcp_add_binary_option(packet, client_config.vendorclass);
- }
-}
-static void add_client_options(struct dhcp_packet *packet)
-{
/* Add a "param req" option with the list of options we'd like to have
* from stubborn DHCP servers. Pull the data from the struct in common.c.
* No bounds checking because it goes towards the head of the packet. */
- uint8_t c;
- int end = udhcp_end_option(packet->options);
- int i, len = 0;
-
+ end = udhcp_end_option(packet->options);
+ len = 0;
for (i = 0; (c = dhcp_optflags[i].code) != 0; i++) {
if (( (dhcp_optflags[i].flags & OPTION_REQ)
&& !client_config.no_default_options
{
struct dhcp_packet packet;
+ /* Fill in: op, htype, hlen, cookie, chaddr fields,
+ * random xid field (we override it below),
+ * client-id option (unless -C), message type option:
+ */
init_packet(&packet, DHCPDISCOVER);
+
packet.xid = xid;
if (requested)
udhcp_add_simple_option(&packet, DHCP_REQUESTED_IP, requested);
- /* Explicitly saying that we want RFC-compliant packets helps
- * some buggy DHCP servers to NOT send bigger packets */
- udhcp_add_simple_option(&packet, DHCP_MAX_SIZE, htons(576));
+
+ /* Add options: maxsize,
+ * optionally: hostname, fqdn, vendorclass,
+ * "param req" option according to -O, options specified with -x
+ */
add_client_options(&packet);
bb_info_msg("Sending discover...");
struct dhcp_packet packet;
struct in_addr addr;
+/*
+ * RFC 2131 4.3.2 DHCPREQUEST message
+ * ...
+ * If the DHCPREQUEST message contains a 'server identifier'
+ * option, the message is in response to a DHCPOFFER message.
+ * Otherwise, the message is a request to verify or extend an
+ * existing lease. If the client uses a 'client identifier'
+ * in a DHCPREQUEST message, it MUST use that same 'client identifier'
+ * in all subsequent messages. If the client included a list
+ * of requested parameters in a DHCPDISCOVER message, it MUST
+ * include that list in all subsequent messages.
+ */
+ /* Fill in: op, htype, hlen, cookie, chaddr fields,
+ * random xid field (we override it below),
+ * client-id option (unless -C), message type option:
+ */
init_packet(&packet, DHCPREQUEST);
+
packet.xid = xid;
udhcp_add_simple_option(&packet, DHCP_REQUESTED_IP, requested);
+
udhcp_add_simple_option(&packet, DHCP_SERVER_ID, server);
+
+ /* Add options: maxsize,
+ * optionally: hostname, fqdn, vendorclass,
+ * "param req" option according to -O, and options specified with -x
+ */
add_client_options(&packet);
addr.s_addr = requested;
{
struct dhcp_packet packet;
+/*
+ * RFC 2131 4.3.2 DHCPREQUEST message
+ * ...
+ * DHCPREQUEST generated during RENEWING state:
+ *
+ * 'server identifier' MUST NOT be filled in, 'requested IP address'
+ * option MUST NOT be filled in, 'ciaddr' MUST be filled in with
+ * client's IP address. In this situation, the client is completely
+ * configured, and is trying to extend its lease. This message will
+ * be unicast, so no relay agents will be involved in its
+ * transmission. Because 'giaddr' is therefore not filled in, the
+ * DHCP server will trust the value in 'ciaddr', and use it when
+ * replying to the client.
+ */
+ /* Fill in: op, htype, hlen, cookie, chaddr fields,
+ * random xid field (we override it below),
+ * client-id option (unless -C), message type option:
+ */
init_packet(&packet, DHCPREQUEST);
+
packet.xid = xid;
packet.ciaddr = ciaddr;
+
+ /* Add options: maxsize,
+ * optionally: hostname, fqdn, vendorclass,
+ * "param req" option according to -O, and options specified with -x
+ */
add_client_options(&packet);
bb_info_msg("Sending renew...");
{
struct dhcp_packet packet;
+ /* Fill in: op, htype, hlen, cookie, chaddr, random xid fields,
+ * client-id option (unless -C), message type option:
+ */
init_packet(&packet, DHCPDECLINE);
+
+ /* RFC 2131 says DHCPDECLINE's xid is randomly selected by client,
+ * but in case the server is buggy and wants DHCPDECLINE's xid
+ * to match the xid which started entire handshake,
+ * we use the same xid we used in initial DHCPDISCOVER:
+ */
packet.xid = xid;
+ /* DHCPDECLINE uses "requested ip", not ciaddr, to store offered IP */
udhcp_add_simple_option(&packet, DHCP_REQUESTED_IP, requested);
+
udhcp_add_simple_option(&packet, DHCP_SERVER_ID, server);
bb_info_msg("Sending decline...");
{
struct dhcp_packet packet;
+ /* Fill in: op, htype, hlen, cookie, chaddr, random xid fields,
+ * client-id option (unless -C), message type option:
+ */
init_packet(&packet, DHCPRELEASE);
- packet.xid = random_xid();
+
+ /* DHCPRELEASE uses ciaddr, not "requested ip", to store IP being released */
packet.ciaddr = ciaddr;
udhcp_add_simple_option(&packet, DHCP_SERVER_ID, server);
//usage:#endif
//usage:#define udhcpc_trivial_usage
//usage: "[-fbnq"IF_UDHCP_VERBOSE("v")"oCR] [-i IFACE] [-r IP] [-s PROG] [-p PIDFILE]\n"
-//usage: " [-H HOSTNAME] [-c CID] [-V VENDOR] [-O DHCP_OPT]..." IF_FEATURE_UDHCP_PORT(" [-P N]")
+//usage: " [-H HOSTNAME] [-V VENDOR] [-x OPT:VAL]... [-O OPT]..." IF_FEATURE_UDHCP_PORT(" [-P N]")
//usage:#define udhcpc_full_usage "\n"
//usage: IF_LONG_OPTS(
//usage: "\n -i,--interface IFACE Interface to use (default eth0)"
//usage: "\n -p,--pidfile FILE Create pidfile"
-//usage: "\n -r,--request IP IP address to request"
//usage: "\n -s,--script PROG Run PROG at DHCP events (default "CONFIG_UDHCPC_DEFAULT_SCRIPT")"
//usage: "\n -t,--retries N Send up to N discover packets"
//usage: "\n -T,--timeout N Pause between packets (default 3 seconds)"
//usage: USE_FOR_MMU(
//usage: "\n -b,--background Background if lease is not obtained"
//usage: )
-//usage: "\n -S,--syslog Log to syslog too"
//usage: "\n -n,--now Exit if lease is not obtained"
//usage: "\n -q,--quit Exit after obtaining lease"
//usage: "\n -R,--release Release IP on exit"
+//usage: "\n -S,--syslog Log to syslog too"
//usage: IF_FEATURE_UDHCP_PORT(
//usage: "\n -P,--client-port N Use port N (default 68)"
//usage: )
//usage: IF_FEATURE_UDHCPC_ARPING(
//usage: "\n -a,--arping Use arping to validate offered address"
//usage: )
-//usage: "\n -O,--request-option OPT Request DHCP option OPT (cumulative)"
+//usage: "\n -O,--request-option OPT Request option OPT from server (cumulative)"
//usage: "\n -o,--no-default-options Don't request any options (unless -O is given)"
+//usage: "\n -r,--request IP Request this IP address"
//usage: "\n -x OPT:VAL Include option OPT in sent packets (cumulative)"
+//usage: "\n Examples of string, numeric, and hex byte opts:"
+//usage: "\n -x hostname:bbox - option 12"
+//usage: "\n -x lease:3600 - option 51 (lease time)"
+//usage: "\n -x 0x3d:0100BEEFC0FFEE - option 61 (client id)"
//usage: "\n -F,--fqdn NAME Ask server to update DNS mapping for NAME"
//usage: "\n -H,-h,--hostname NAME Send NAME as client hostname (default none)"
//usage: "\n -V,--vendorclass VENDOR Vendor identifier (default 'udhcp VERSION')"
-//usage: "\n -c,--clientid CLIENTID Client identifier (default own MAC)"
-//usage: "\n -C,--clientid-none Don't send client identifier"
+//usage: "\n -C,--clientid-none Don't send MAC as client identifier"
//usage: IF_UDHCP_VERBOSE(
//usage: "\n -v Verbose"
//usage: )
//usage: IF_NOT_LONG_OPTS(
//usage: "\n -i IFACE Interface to use (default eth0)"
//usage: "\n -p FILE Create pidfile"
-//usage: "\n -r IP IP address to request"
//usage: "\n -s PROG Run PROG at DHCP events (default "CONFIG_UDHCPC_DEFAULT_SCRIPT")"
//usage: "\n -t N Send up to N discover packets"
//usage: "\n -T N Pause between packets (default 3 seconds)"
//usage: "\n -A N Wait N seconds (default 20) after failure"
-//usage: "\n -x OPT:VAL Include option OPT in sent packets"
-//usage: "\n -O OPT Request DHCP option OPT (cumulative)"
-//usage: "\n -o Don't request any options (unless -O is given)"
//usage: "\n -f Run in foreground"
//usage: USE_FOR_MMU(
//usage: "\n -b Background if lease is not obtained"
//usage: )
-//usage: "\n -S Log to syslog too"
//usage: "\n -n Exit if lease is not obtained"
//usage: "\n -q Exit after obtaining lease"
//usage: "\n -R Release IP on exit"
+//usage: "\n -S Log to syslog too"
//usage: IF_FEATURE_UDHCP_PORT(
//usage: "\n -P N Use port N (default 68)"
//usage: )
//usage: IF_FEATURE_UDHCPC_ARPING(
//usage: "\n -a Use arping to validate offered address"
//usage: )
+//usage: "\n -O OPT Request option OPT from server (cumulative)"
+//usage: "\n -o Don't request any options (unless -O is given)"
+//usage: "\n -r IP Request this IP address"
+//usage: "\n -x OPT:VAL Include option OPT in sent packets (cumulative)"
+//usage: "\n Examples of string, numeric, and hex byte opts:"
+//usage: "\n -x hostname:bbox - option 12"
+//usage: "\n -x lease:3600 - option 51 (lease time)"
+//usage: "\n -x 0x3d:0100BEEFC0FFEE - option 61 (client id)"
//usage: "\n -F NAME Ask server to update DNS mapping for NAME"
//usage: "\n -H,-h NAME Send NAME as client hostname (default none)"
//usage: "\n -V VENDOR Vendor identifier (default 'udhcp VERSION')"
-//usage: "\n -c CLIENTID Client identifier (default own MAC)"
-//usage: "\n -C Don't send client identifier"
+//usage: "\n -C Don't send MAC as client identifier"
//usage: IF_UDHCP_VERBOSE(
//usage: "\n -v Verbose"
//usage: )
int udhcpc_main(int argc UNUSED_PARAM, char **argv)
{
uint8_t *temp, *message;
- const char *str_c, *str_V, *str_h, *str_F, *str_r;
+ const char *str_V, *str_h, *str_F, *str_r;
IF_FEATURE_UDHCP_PORT(char *str_P;)
llist_t *list_O = NULL;
llist_t *list_x = NULL;
#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"
"hostname\0" Required_argument "H"
;
#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_x = 1 << 19,
- OPT_f = 1 << 20,
+ OPT_C = 1 << 0,
+ OPT_V = 1 << 1,
+ OPT_H = 1 << 2,
+ OPT_h = 1 << 3,
+ OPT_F = 1 << 4,
+ OPT_i = 1 << 5,
+ OPT_n = 1 << 6,
+ OPT_p = 1 << 7,
+ OPT_q = 1 << 8,
+ OPT_R = 1 << 9,
+ OPT_r = 1 << 10,
+ OPT_s = 1 << 11,
+ OPT_T = 1 << 12,
+ OPT_t = 1 << 13,
+ OPT_S = 1 << 14,
+ OPT_A = 1 << 15,
+ OPT_O = 1 << 16,
+ OPT_o = 1 << 17,
+ OPT_x = 1 << 18,
+ OPT_f = 1 << 19,
/* The rest has variable bit positions, need to be clever */
- OPTBIT_f = 20,
+ OPTBIT_f = 19,
USE_FOR_MMU( OPTBIT_b,)
IF_FEATURE_UDHCPC_ARPING(OPTBIT_a,)
IF_FEATURE_UDHCP_PORT( OPTBIT_P,)
str_V = "udhcp "BB_VER;
/* Parse command line */
- /* Cc: mutually exclusive; O,x: list; -T,-t,-A take numeric param */
- opt_complementary = "c--C:C--c:O::x::T+:t+:A+"
+ /* O,x: list; -T,-t,-A take numeric param */
+ opt_complementary = "O::x::T+:t+:A+"
#if defined CONFIG_UDHCP_DEBUG && CONFIG_UDHCP_DEBUG >= 1
":vv"
#endif
;
IF_LONG_OPTS(applet_long_options = udhcpc_longopts;)
- opt = getopt32(argv, "c:CV:H:h:F:i:np:qRr:s:T:t:SA:O:ox:f"
+ opt = getopt32(argv, "CV:H:h:F:i:np:qRr:s:T:t:SA:O:ox:f"
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
+ , &str_V, &str_h, &str_h, &str_F
, &client_config.interface, &client_config.pidfile, &str_r /* i,p */
, &client_config.script /* s */
, &discover_timeout, &discover_retries, &tryagain_timeout /* T,t,A */
return 1;
}
- if (opt & OPT_c) {
- client_config.clientid = alloc_dhcp_option(DHCP_CLIENT_ID, str_c, 0);
- } else if (!(opt & OPT_C)) {
- /* not set and not suppressed, set the default client ID */
+ if (!(opt & OPT_C) && !udhcp_find_option(client_config.options, DHCP_CLIENT_ID)) {
+ /* not suppressed and not set, set the default client ID */
client_config.clientid = alloc_dhcp_option(DHCP_CLIENT_ID, "", 7);
client_config.clientid[OPT_DATA] = 1; /* type: ethernet */
memcpy(client_config.clientid + OPT_DATA+1, client_config.client_mac, 6);
* resend discover/renew/whatever
*/
if (retval == 0) {
+ /* When running on a bridge, the ifindex may have changed
+ * (e.g. if member interfaces were added/removed
+ * or if the status of the bridge changed).
+ * Refresh ifindex and client_mac:
+ */
+ udhcp_read_interface(client_config.interface,
+ &client_config.ifindex,
+ NULL,
+ client_config.client_mac);
+
/* We will restart the wait in any case */
already_waited_sec = 0;
/* Ignore packets that aren't for us */
if (packet.hlen != 6
- || memcmp(packet.chaddr, client_config.client_mac, 6)
+ || memcmp(packet.chaddr, client_config.client_mac, 6) != 0
) {
//FIXME: need to also check that last 10 bytes are zero
log1("chaddr does not match, ignoring packet"); // log2?
}
/* it IS unaligned sometimes, don't "optimize" */
move_from_unaligned32(server_addr, temp);
- xid = packet.xid;
+ /*xid = packet.xid; - already is */
requested_ip = packet.yiaddr;
/* enter requesting state */
projects / oweals / busybox.git / blobdiff