[1770] | 1 | /* vi: set sw=4 ts=4: */
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[821] | 2 | /* dhcpc.c
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| 3 | *
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| 4 | * udhcp DHCP client
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| 5 | *
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| 6 | * Russ Dill <Russ.Dill@asu.edu> July 2001
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| 7 | *
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| 8 | * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
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| 9 | */
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| 10 |
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| 11 | #include <getopt.h>
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[1770] | 12 | #include <syslog.h>
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[821] | 13 |
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[1770] | 14 | /* Override ENABLE_FEATURE_PIDFILE - ifupdown needs our pidfile to always exist */
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| 15 | #define WANT_PIDFILE 1
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[821] | 16 | #include "common.h"
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| 17 | #include "dhcpd.h"
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| 18 | #include "dhcpc.h"
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| 19 | #include "options.h"
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| 20 |
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[1770] | 21 |
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| 22 | /* Something is definitely wrong here. IPv4 addresses
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| 23 | * in variables of type long?? BTW, we use inet_ntoa()
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| 24 | * in the code. Manpage says that struct in_addr has a member of type long (!)
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| 25 | * which holds IPv4 address, and the struct is passed by value (!!)
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| 26 | */
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| 27 | static unsigned timeout;
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| 28 | static uint32_t requested_ip; /* = 0 */
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| 29 | static uint32_t server_addr;
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[821] | 30 | static int packet_num; /* = 0 */
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[1770] | 31 | static int sockfd = -1;
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[821] | 32 |
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| 33 | #define LISTEN_NONE 0
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| 34 | #define LISTEN_KERNEL 1
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| 35 | #define LISTEN_RAW 2
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[1770] | 36 | static smallint listen_mode;
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[821] | 37 |
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[1770] | 38 | static smallint state;
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[821] | 39 |
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[1770] | 40 | struct client_config_t client_config;
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| 41 |
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| 42 |
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[821] | 43 | /* just a little helper */
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| 44 | static void change_mode(int new_mode)
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| 45 | {
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[1770] | 46 | DEBUG("entering %s listen mode",
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[821] | 47 | new_mode ? (new_mode == 1 ? "kernel" : "raw") : "none");
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[1770] | 48 | if (sockfd >= 0) {
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| 49 | close(sockfd);
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| 50 | sockfd = -1;
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| 51 | }
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[821] | 52 | listen_mode = new_mode;
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| 53 | }
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| 54 |
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| 55 |
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| 56 | /* perform a renew */
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| 57 | static void perform_renew(void)
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| 58 | {
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[1770] | 59 | bb_info_msg("Performing a DHCP renew");
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[821] | 60 | switch (state) {
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| 61 | case BOUND:
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| 62 | change_mode(LISTEN_KERNEL);
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| 63 | case RENEWING:
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| 64 | case REBINDING:
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| 65 | state = RENEW_REQUESTED;
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| 66 | break;
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| 67 | case RENEW_REQUESTED: /* impatient are we? fine, square 1 */
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| 68 | udhcp_run_script(NULL, "deconfig");
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| 69 | case REQUESTING:
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| 70 | case RELEASED:
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| 71 | change_mode(LISTEN_RAW);
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| 72 | state = INIT_SELECTING;
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| 73 | break;
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| 74 | case INIT_SELECTING:
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| 75 | break;
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| 76 | }
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| 77 |
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| 78 | /* start things over */
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| 79 | packet_num = 0;
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| 80 |
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| 81 | /* Kill any timeouts because the user wants this to hurry along */
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| 82 | timeout = 0;
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| 83 | }
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| 84 |
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| 85 |
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| 86 | /* perform a release */
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| 87 | static void perform_release(void)
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| 88 | {
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[1770] | 89 | char buffer[sizeof("255.255.255.255")];
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[821] | 90 | struct in_addr temp_addr;
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| 91 |
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| 92 | /* send release packet */
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| 93 | if (state == BOUND || state == RENEWING || state == REBINDING) {
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| 94 | temp_addr.s_addr = server_addr;
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[1770] | 95 | strcpy(buffer, inet_ntoa(temp_addr));
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[821] | 96 | temp_addr.s_addr = requested_ip;
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[1770] | 97 | bb_info_msg("Unicasting a release of %s to %s",
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[821] | 98 | inet_ntoa(temp_addr), buffer);
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| 99 | send_release(server_addr, requested_ip); /* unicast */
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| 100 | udhcp_run_script(NULL, "deconfig");
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| 101 | }
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[1770] | 102 | bb_info_msg("Entering released state");
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[821] | 103 |
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| 104 | change_mode(LISTEN_NONE);
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| 105 | state = RELEASED;
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[1770] | 106 | timeout = INT_MAX;
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[821] | 107 | }
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| 108 |
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| 109 |
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| 110 | static void client_background(void)
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| 111 | {
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[1770] | 112 | #if !BB_MMU
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| 113 | bb_error_msg("cannot background in uclinux (yet)");
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| 114 | /* ... mainly because udhcpc calls client_background()
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| 115 | * in _the _middle _of _udhcpc _run_, not at the start!
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| 116 | * If that will be properly disabled for NOMMU, client_background()
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| 117 | * will work on NOMMU too */
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| 118 | #else
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| 119 | bb_daemonize(0);
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| 120 | logmode &= ~LOGMODE_STDIO;
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| 121 | /* rewrite pidfile, as our pid is different now */
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| 122 | write_pidfile(client_config.pidfile);
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| 123 | #endif
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| 124 | /* Do not fork again. */
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| 125 | client_config.foreground = 1;
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[821] | 126 | client_config.background_if_no_lease = 0;
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| 127 | }
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| 128 |
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| 129 |
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[1770] | 130 | static uint8_t* alloc_dhcp_option(int code, const char *str, int extra)
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[821] | 131 | {
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[1770] | 132 | uint8_t *storage;
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| 133 | int len = strlen(str);
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| 134 | if (len > 255) len = 255;
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| 135 | storage = xzalloc(len + extra + OPT_DATA);
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| 136 | storage[OPT_CODE] = code;
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| 137 | storage[OPT_LEN] = len + extra;
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| 138 | memcpy(storage + extra + OPT_DATA, str, len);
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| 139 | return storage;
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| 140 | }
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| 141 |
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| 142 |
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| 143 | int udhcpc_main(int argc, char **argv);
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| 144 | int udhcpc_main(int argc, char **argv)
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| 145 | {
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[821] | 146 | uint8_t *temp, *message;
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[1770] | 147 | char *str_c, *str_V, *str_h, *str_F, *str_r, *str_T, *str_t;
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| 148 | uint32_t xid = 0;
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| 149 | uint32_t lease = 0; /* can be given as 32-bit quantity */
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| 150 | unsigned t1 = 0, t2 = 0; /* what a wonderful names */
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| 151 | unsigned start = 0;
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| 152 | unsigned now;
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| 153 | unsigned opt;
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| 154 | int max_fd;
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[821] | 155 | int retval;
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[1770] | 156 | int len;
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[821] | 157 | struct timeval tv;
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[1770] | 158 | struct in_addr temp_addr;
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[821] | 159 | struct dhcpMessage packet;
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[1770] | 160 | fd_set rfds;
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[821] | 161 |
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[1770] | 162 | enum {
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| 163 | OPT_c = 1 << 0,
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| 164 | OPT_C = 1 << 1,
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| 165 | OPT_V = 1 << 2,
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| 166 | OPT_f = 1 << 3,
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| 167 | OPT_b = 1 << 4,
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| 168 | OPT_H = 1 << 5,
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| 169 | OPT_h = 1 << 6,
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| 170 | OPT_F = 1 << 7,
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| 171 | OPT_i = 1 << 8,
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| 172 | OPT_n = 1 << 9,
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| 173 | OPT_p = 1 << 10,
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| 174 | OPT_q = 1 << 11,
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| 175 | OPT_R = 1 << 12,
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| 176 | OPT_r = 1 << 13,
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| 177 | OPT_s = 1 << 14,
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| 178 | OPT_T = 1 << 15,
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| 179 | OPT_t = 1 << 16,
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| 180 | OPT_v = 1 << 17,
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| 181 | OPT_S = 1 << 18,
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[821] | 182 | };
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[1770] | 183 | #if ENABLE_GETOPT_LONG
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| 184 | static const char udhcpc_longopts[] ALIGN1 =
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| 185 | "clientid\0" Required_argument "c"
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| 186 | "clientid-none\0" No_argument "C"
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| 187 | "vendorclass\0" Required_argument "V"
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| 188 | "foreground\0" No_argument "f"
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| 189 | "background\0" No_argument "b"
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| 190 | "hostname\0" Required_argument "H"
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| 191 | "hostname\0" Required_argument "h"
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| 192 | "fqdn\0" Required_argument "F"
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| 193 | "interface\0" Required_argument "i"
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| 194 | "now\0" No_argument "n"
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| 195 | "pidfile\0" Required_argument "p"
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| 196 | "quit\0" No_argument "q"
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| 197 | "release\0" No_argument "R"
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| 198 | "request\0" Required_argument "r"
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| 199 | "script\0" Required_argument "s"
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| 200 | "timeout\0" Required_argument "T"
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| 201 | "version\0" No_argument "v"
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| 202 | "retries\0" Required_argument "t"
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| 203 | "syslog\0" No_argument "S"
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| 204 | ;
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| 205 | #endif
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| 206 | /* Default options. */
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| 207 | client_config.interface = "eth0";
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| 208 | client_config.script = DEFAULT_SCRIPT;
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| 209 | client_config.retries = 3;
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| 210 | client_config.timeout = 3;
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[821] | 211 |
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[1770] | 212 | /* Parse command line */
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| 213 | opt_complementary = "c--C:C--c" // mutually exclusive
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| 214 | ":hH:Hh"; // -h and -H are the same
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| 215 | #if ENABLE_GETOPT_LONG
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| 216 | applet_long_options = udhcpc_longopts;
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| 217 | #endif
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| 218 | opt = getopt32(argv, "c:CV:fbH:h:F:i:np:qRr:s:T:t:vS",
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| 219 | &str_c, &str_V, &str_h, &str_h, &str_F,
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| 220 | &client_config.interface, &client_config.pidfile, &str_r,
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| 221 | &client_config.script, &str_T, &str_t
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| 222 | );
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[821] | 223 |
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[1770] | 224 | if (opt & OPT_c)
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| 225 | client_config.clientid = alloc_dhcp_option(DHCP_CLIENT_ID, str_c, 0);
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| 226 | //if (opt & OPT_C)
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| 227 | if (opt & OPT_V)
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| 228 | client_config.vendorclass = alloc_dhcp_option(DHCP_VENDOR, str_V, 0);
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| 229 | if (opt & OPT_f)
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| 230 | client_config.foreground = 1;
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| 231 | if (opt & OPT_b)
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| 232 | client_config.background_if_no_lease = 1;
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| 233 | if (opt & OPT_h)
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| 234 | client_config.hostname = alloc_dhcp_option(DHCP_HOST_NAME, str_h, 0);
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| 235 | if (opt & OPT_F) {
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| 236 | client_config.fqdn = alloc_dhcp_option(DHCP_FQDN, str_F, 3);
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| 237 | /* Flags: 0000NEOS
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| 238 | S: 1 => Client requests Server to update A RR in DNS as well as PTR
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| 239 | O: 1 => Server indicates to client that DNS has been updated regardless
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| 240 | E: 1 => Name data is DNS format, i.e. <4>host<6>domain<4>com<0> not "host.domain.com"
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| 241 | N: 1 => Client requests Server to not update DNS
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| 242 | */
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| 243 | client_config.fqdn[OPT_DATA + 0] = 0x1;
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| 244 | /* client_config.fqdn[OPT_DATA + 1] = 0; - redundant */
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| 245 | /* client_config.fqdn[OPT_DATA + 2] = 0; - redundant */
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[821] | 246 | }
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[1770] | 247 | // if (opt & OPT_i) client_config.interface = ...
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| 248 | if (opt & OPT_n)
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| 249 | client_config.abort_if_no_lease = 1;
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| 250 | // if (opt & OPT_p) client_config.pidfile = ...
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| 251 | if (opt & OPT_q)
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| 252 | client_config.quit_after_lease = 1;
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| 253 | if (opt & OPT_R)
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| 254 | client_config.release_on_quit = 1;
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| 255 | if (opt & OPT_r)
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| 256 | requested_ip = inet_addr(str_r);
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| 257 | // if (opt & OPT_s) client_config.script = ...
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| 258 | if (opt & OPT_T)
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| 259 | client_config.timeout = xatoi_u(str_T);
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| 260 | if (opt & OPT_t)
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| 261 | client_config.retries = xatoi_u(str_t);
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| 262 | if (opt & OPT_v) {
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| 263 | printf("version %s\n", BB_VER);
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| 264 | return 0;
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| 265 | }
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[821] | 266 |
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[1770] | 267 | if (opt & OPT_S) {
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| 268 | openlog(applet_name, LOG_PID, LOG_LOCAL0);
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| 269 | logmode |= LOGMODE_SYSLOG;
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| 270 | }
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[821] | 271 |
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| 272 | if (read_interface(client_config.interface, &client_config.ifindex,
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[1770] | 273 | NULL, client_config.arp))
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[821] | 274 | return 1;
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| 275 |
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[1770] | 276 | /* Make sure fd 0,1,2 are open */
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| 277 | bb_sanitize_stdio();
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| 278 | /* Equivalent of doing a fflush after every \n */
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| 279 | setlinebuf(stdout);
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| 280 |
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| 281 | /* Create pidfile */
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| 282 | write_pidfile(client_config.pidfile);
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| 283 | /* if (!..) bb_perror_msg("cannot create pidfile %s", pidfile); */
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| 284 |
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| 285 | /* Goes to stdout and possibly syslog */
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| 286 | bb_info_msg("%s (v%s) started", applet_name, BB_VER);
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| 287 |
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[821] | 288 | /* if not set, and not suppressed, setup the default client ID */
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[1770] | 289 | if (!client_config.clientid && !(opt & OPT_C)) {
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| 290 | client_config.clientid = alloc_dhcp_option(DHCP_CLIENT_ID, "", 7);
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[821] | 291 | client_config.clientid[OPT_DATA] = 1;
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[1770] | 292 | memcpy(client_config.clientid + OPT_DATA+1, client_config.arp, 6);
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[821] | 293 | }
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| 294 |
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[1770] | 295 | if (!client_config.vendorclass)
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| 296 | client_config.vendorclass = alloc_dhcp_option(DHCP_VENDOR, "udhcp "BB_VER, 0);
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[821] | 297 |
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| 298 | /* setup the signal pipe */
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| 299 | udhcp_sp_setup();
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| 300 |
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| 301 | state = INIT_SELECTING;
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| 302 | udhcp_run_script(NULL, "deconfig");
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| 303 | change_mode(LISTEN_RAW);
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[1770] | 304 | tv.tv_sec = 0;
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| 305 | goto jump_in;
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[821] | 306 |
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| 307 | for (;;) {
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[1770] | 308 | tv.tv_sec = timeout - monotonic_sec();
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| 309 | jump_in:
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[821] | 310 | tv.tv_usec = 0;
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| 311 |
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[1770] | 312 | if (listen_mode != LISTEN_NONE && sockfd < 0) {
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[821] | 313 | if (listen_mode == LISTEN_KERNEL)
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[1770] | 314 | sockfd = listen_socket(/*INADDR_ANY,*/ CLIENT_PORT, client_config.interface);
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[821] | 315 | else
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[1770] | 316 | sockfd = raw_socket(client_config.ifindex);
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[821] | 317 | }
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[1770] | 318 | max_fd = udhcp_sp_fd_set(&rfds, sockfd);
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[821] | 319 |
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[1770] | 320 | retval = 0; /* If we already timed out, fall through, else... */
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[821] | 321 | if (tv.tv_sec > 0) {
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[1770] | 322 | DEBUG("Waiting on select...");
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[821] | 323 | retval = select(max_fd + 1, &rfds, NULL, NULL, &tv);
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[1770] | 324 | }
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[821] | 325 |
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[1770] | 326 | now = monotonic_sec();
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| 327 | if (retval < 0) {
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| 328 | /* EINTR? signal was caught, don't panic */
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| 329 | if (errno != EINTR) {
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| 330 | /* Else: an error occured, panic! */
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| 331 | bb_perror_msg_and_die("select");
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| 332 | }
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| 333 | } else if (retval == 0) {
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[821] | 334 | /* timeout dropped to zero */
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| 335 | switch (state) {
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| 336 | case INIT_SELECTING:
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| 337 | if (packet_num < client_config.retries) {
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| 338 | if (packet_num == 0)
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| 339 | xid = random_xid();
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| 340 |
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| 341 | /* send discover packet */
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| 342 | send_discover(xid, requested_ip); /* broadcast */
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| 343 |
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| 344 | timeout = now + client_config.timeout;
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| 345 | packet_num++;
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| 346 | } else {
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| 347 | udhcp_run_script(NULL, "leasefail");
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| 348 | if (client_config.background_if_no_lease) {
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[1770] | 349 | bb_info_msg("No lease, forking to background");
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[821] | 350 | client_background();
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| 351 | } else if (client_config.abort_if_no_lease) {
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[1770] | 352 | bb_info_msg("No lease, failing");
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| 353 | retval = 1;
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| 354 | goto ret;
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[821] | 355 | }
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| 356 | /* wait to try again */
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| 357 | packet_num = 0;
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| 358 | timeout = now + 60;
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| 359 | }
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| 360 | break;
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| 361 | case RENEW_REQUESTED:
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| 362 | case REQUESTING:
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| 363 | if (packet_num < client_config.retries) {
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| 364 | /* send request packet */
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| 365 | if (state == RENEW_REQUESTED)
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| 366 | send_renew(xid, server_addr, requested_ip); /* unicast */
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| 367 | else send_selecting(xid, server_addr, requested_ip); /* broadcast */
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| 368 |
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| 369 | timeout = now + ((packet_num == 2) ? 10 : 2);
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| 370 | packet_num++;
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| 371 | } else {
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| 372 | /* timed out, go back to init state */
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[1770] | 373 | if (state == RENEW_REQUESTED)
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| 374 | udhcp_run_script(NULL, "deconfig");
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[821] | 375 | state = INIT_SELECTING;
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| 376 | timeout = now;
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| 377 | packet_num = 0;
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| 378 | change_mode(LISTEN_RAW);
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| 379 | }
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| 380 | break;
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| 381 | case BOUND:
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| 382 | /* Lease is starting to run out, time to enter renewing state */
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| 383 | state = RENEWING;
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| 384 | change_mode(LISTEN_KERNEL);
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[1770] | 385 | DEBUG("Entering renew state");
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[821] | 386 | /* fall right through */
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| 387 | case RENEWING:
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| 388 | /* Either set a new T1, or enter REBINDING state */
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| 389 | if ((t2 - t1) <= (lease / 14400 + 1)) {
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| 390 | /* timed out, enter rebinding state */
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| 391 | state = REBINDING;
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| 392 | timeout = now + (t2 - t1);
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[1770] | 393 | DEBUG("Entering rebinding state");
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[821] | 394 | } else {
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| 395 | /* send a request packet */
|
---|
| 396 | send_renew(xid, server_addr, requested_ip); /* unicast */
|
---|
| 397 | t1 = (t2 - t1) / 2 + t1;
|
---|
[1770] | 398 | timeout = start + t1;
|
---|
[821] | 399 | }
|
---|
| 400 | break;
|
---|
| 401 | case REBINDING:
|
---|
| 402 | /* Either set a new T2, or enter INIT state */
|
---|
| 403 | if ((lease - t2) <= (lease / 14400 + 1)) {
|
---|
| 404 | /* timed out, enter init state */
|
---|
| 405 | state = INIT_SELECTING;
|
---|
[1770] | 406 | bb_info_msg("Lease lost, entering init state");
|
---|
[821] | 407 | udhcp_run_script(NULL, "deconfig");
|
---|
| 408 | timeout = now;
|
---|
| 409 | packet_num = 0;
|
---|
| 410 | change_mode(LISTEN_RAW);
|
---|
| 411 | } else {
|
---|
| 412 | /* send a request packet */
|
---|
| 413 | send_renew(xid, 0, requested_ip); /* broadcast */
|
---|
| 414 | t2 = (lease - t2) / 2 + t2;
|
---|
[1770] | 415 | timeout = start + t2;
|
---|
[821] | 416 | }
|
---|
| 417 | break;
|
---|
| 418 | case RELEASED:
|
---|
| 419 | /* yah, I know, *you* say it would never happen */
|
---|
[1770] | 420 | timeout = INT_MAX;
|
---|
[821] | 421 | break;
|
---|
| 422 | }
|
---|
[1770] | 423 | } else if (listen_mode != LISTEN_NONE && FD_ISSET(sockfd, &rfds)) {
|
---|
[821] | 424 | /* a packet is ready, read it */
|
---|
| 425 |
|
---|
| 426 | if (listen_mode == LISTEN_KERNEL)
|
---|
[1770] | 427 | len = udhcp_get_packet(&packet, sockfd);
|
---|
| 428 | else len = get_raw_packet(&packet, sockfd);
|
---|
[821] | 429 |
|
---|
| 430 | if (len == -1 && errno != EINTR) {
|
---|
[1770] | 431 | DEBUG("error on read, %s, reopening socket", strerror(errno));
|
---|
[821] | 432 | change_mode(listen_mode); /* just close and reopen */
|
---|
| 433 | }
|
---|
| 434 | if (len < 0) continue;
|
---|
| 435 |
|
---|
| 436 | if (packet.xid != xid) {
|
---|
[1770] | 437 | DEBUG("Ignoring XID %x (our xid is %x)",
|
---|
| 438 | (unsigned)packet.xid, (unsigned)xid);
|
---|
[821] | 439 | continue;
|
---|
| 440 | }
|
---|
| 441 |
|
---|
| 442 | /* Ignore packets that aren't for us */
|
---|
| 443 | if (memcmp(packet.chaddr, client_config.arp, 6)) {
|
---|
[1770] | 444 | DEBUG("Packet does not have our chaddr - ignoring");
|
---|
[821] | 445 | continue;
|
---|
| 446 | }
|
---|
| 447 |
|
---|
[1770] | 448 | message = get_option(&packet, DHCP_MESSAGE_TYPE);
|
---|
| 449 | if (message == NULL) {
|
---|
| 450 | bb_error_msg("cannot get option from packet - ignoring");
|
---|
[821] | 451 | continue;
|
---|
| 452 | }
|
---|
| 453 |
|
---|
| 454 | switch (state) {
|
---|
| 455 | case INIT_SELECTING:
|
---|
| 456 | /* Must be a DHCPOFFER to one of our xid's */
|
---|
| 457 | if (*message == DHCPOFFER) {
|
---|
[1770] | 458 | temp = get_option(&packet, DHCP_SERVER_ID);
|
---|
| 459 | if (temp) {
|
---|
| 460 | /* can be misaligned, thus memcpy */
|
---|
[821] | 461 | memcpy(&server_addr, temp, 4);
|
---|
| 462 | xid = packet.xid;
|
---|
| 463 | requested_ip = packet.yiaddr;
|
---|
| 464 |
|
---|
| 465 | /* enter requesting state */
|
---|
| 466 | state = REQUESTING;
|
---|
| 467 | timeout = now;
|
---|
| 468 | packet_num = 0;
|
---|
| 469 | } else {
|
---|
[1770] | 470 | bb_error_msg("no server ID in message");
|
---|
[821] | 471 | }
|
---|
| 472 | }
|
---|
| 473 | break;
|
---|
| 474 | case RENEW_REQUESTED:
|
---|
| 475 | case REQUESTING:
|
---|
| 476 | case RENEWING:
|
---|
| 477 | case REBINDING:
|
---|
| 478 | if (*message == DHCPACK) {
|
---|
[1770] | 479 | temp = get_option(&packet, DHCP_LEASE_TIME);
|
---|
| 480 | if (!temp) {
|
---|
| 481 | bb_error_msg("no lease time with ACK, using 1 hour lease");
|
---|
[821] | 482 | lease = 60 * 60;
|
---|
| 483 | } else {
|
---|
[1770] | 484 | /* can be misaligned, thus memcpy */
|
---|
[821] | 485 | memcpy(&lease, temp, 4);
|
---|
| 486 | lease = ntohl(lease);
|
---|
| 487 | }
|
---|
| 488 |
|
---|
| 489 | /* enter bound state */
|
---|
| 490 | t1 = lease / 2;
|
---|
| 491 |
|
---|
| 492 | /* little fixed point for n * .875 */
|
---|
[1770] | 493 | t2 = (lease * 7) >> 3;
|
---|
[821] | 494 | temp_addr.s_addr = packet.yiaddr;
|
---|
[1770] | 495 | bb_info_msg("Lease of %s obtained, lease time %u",
|
---|
| 496 | inet_ntoa(temp_addr), (unsigned)lease);
|
---|
[821] | 497 | start = now;
|
---|
[1770] | 498 | timeout = start + t1;
|
---|
[821] | 499 | requested_ip = packet.yiaddr;
|
---|
| 500 | udhcp_run_script(&packet,
|
---|
| 501 | ((state == RENEWING || state == REBINDING) ? "renew" : "bound"));
|
---|
| 502 |
|
---|
| 503 | state = BOUND;
|
---|
| 504 | change_mode(LISTEN_NONE);
|
---|
[1770] | 505 | if (client_config.quit_after_lease) {
|
---|
| 506 | if (client_config.release_on_quit)
|
---|
| 507 | perform_release();
|
---|
| 508 | goto ret0;
|
---|
| 509 | }
|
---|
[821] | 510 | if (!client_config.foreground)
|
---|
| 511 | client_background();
|
---|
| 512 |
|
---|
| 513 | } else if (*message == DHCPNAK) {
|
---|
| 514 | /* return to init state */
|
---|
[1770] | 515 | bb_info_msg("Received DHCP NAK");
|
---|
[821] | 516 | udhcp_run_script(&packet, "nak");
|
---|
| 517 | if (state != REQUESTING)
|
---|
| 518 | udhcp_run_script(NULL, "deconfig");
|
---|
| 519 | state = INIT_SELECTING;
|
---|
| 520 | timeout = now;
|
---|
| 521 | requested_ip = 0;
|
---|
| 522 | packet_num = 0;
|
---|
| 523 | change_mode(LISTEN_RAW);
|
---|
| 524 | sleep(3); /* avoid excessive network traffic */
|
---|
| 525 | }
|
---|
| 526 | break;
|
---|
| 527 | /* case BOUND, RELEASED: - ignore all packets */
|
---|
| 528 | }
|
---|
[1770] | 529 | } else {
|
---|
| 530 | int signo = udhcp_sp_read(&rfds);
|
---|
| 531 | switch (signo) {
|
---|
[821] | 532 | case SIGUSR1:
|
---|
| 533 | perform_renew();
|
---|
| 534 | break;
|
---|
| 535 | case SIGUSR2:
|
---|
| 536 | perform_release();
|
---|
| 537 | break;
|
---|
| 538 | case SIGTERM:
|
---|
[1770] | 539 | bb_info_msg("Received SIGTERM");
|
---|
| 540 | if (client_config.release_on_quit)
|
---|
| 541 | perform_release();
|
---|
| 542 | goto ret0;
|
---|
[821] | 543 | }
|
---|
| 544 | }
|
---|
[1770] | 545 | } /* for (;;) */
|
---|
| 546 | ret0:
|
---|
| 547 | retval = 0;
|
---|
| 548 | ret:
|
---|
| 549 | /*if (client_config.pidfile) - remove_pidfile has it's own check */
|
---|
| 550 | remove_pidfile(client_config.pidfile);
|
---|
| 551 | return retval;
|
---|
[821] | 552 | }
|
---|