diff options
Diffstat (limited to 'networking')
| -rw-r--r-- | networking/udhcp/dhcpc.c | 299 |
1 files changed, 151 insertions, 148 deletions
diff --git a/networking/udhcp/dhcpc.c b/networking/udhcp/dhcpc.c index fca5c2a..077098f 100644 --- a/networking/udhcp/dhcpc.c +++ b/networking/udhcp/dhcpc.c @@ -307,7 +307,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv) /* 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; @@ -317,7 +317,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv) 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; @@ -467,19 +467,45 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv) /* 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(); + /* Start things over */ + packet_num = 0; + /* Kill any timeouts because the 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 it a packet? */ - if (listen_mode != LISTEN_NONE && FD_ISSET(sockfd, &rfds)) { + if (listen_mode == LISTEN_NONE || !FD_ISSET(sockfd, &rfds)) + continue; /* no */ + + { int len; - /* A packet is ready, read it */ + /* A packet is ready, read it */ if (listen_mode == LISTEN_KERNEL) len = udhcp_recv_kernel_packet(&packet, sockfd); else len = udhcp_recv_raw_packet(&packet, sockfd); - if (len == -1) { /* error is severe, reopen socket */ + 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 */ @@ -490,70 +516,71 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv) already_waited_sec += (unsigned)monotonic_sec() - timestamp_before_wait; if (len < 0) continue; + } - if (packet.xid != xid) { - log1("xid %x (our is %x), ignoring packet", - (unsigned)packet.xid, (unsigned)xid); - continue; - } + if (packet.xid != xid) { + log1("xid %x (our is %x), ignoring packet", + (unsigned)packet.xid, (unsigned)xid); + continue; + } - /* Ignore packets that aren't for us */ - if (packet.hlen != 6 - || memcmp(packet.chaddr, client_config.client_mac, 6) - ) { + /* 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; - } + log1("chaddr does not match, ignoring packet"); // log2? + continue; + } - message = get_option(&packet, DHCP_MESSAGE_TYPE); - if (message == NULL) { - bb_error_msg("no message type option, ignoring packet"); - continue; - } + 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 */ - } + 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 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 { /* 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; + 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 { - /* 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; - } #if ENABLE_FEATURE_UDHCPC_ARPING - if (opt & OPT_a) { + 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 @@ -563,100 +590,76 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv) * 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 */ - 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); - } - requested_ip = packet.yiaddr; - udhcp_run_script(&packet, - ((state == RENEWING || state == REBINDING) ? "renew" : "bound")); - - 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; - } -#if BB_MMU /* NOMMU case backgrounded earlier */ - if (!(opt & OPT_f)) { - client_background(); - /* do not background again! */ - opt = ((opt & ~OPT_b) | OPT_f); + 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 - already_waited_sec = 0; - continue; /* back to main loop */ + /* 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); } - 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; - already_waited_sec = 0; + requested_ip = packet.yiaddr; + udhcp_run_script(&packet, + ((state == RENEWING || state == REBINDING) ? "renew" : "bound")); + + 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 */ +#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(requested_ip, server_addr); - timeout = INT_MAX; - break; - case SIGTERM: - bb_info_msg("Received SIGTERM"); - if (opt & OPT_R) /* release on quit */ - perform_release(requested_ip, server_addr); - 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: |