diff options
| -rw-r--r-- | sbin/dhclient/dhclient.c | 206 |
1 files changed, 91 insertions, 115 deletions
diff --git a/sbin/dhclient/dhclient.c b/sbin/dhclient/dhclient.c index aca9a7d2e34..276f809cdd6 100644 --- a/sbin/dhclient/dhclient.c +++ b/sbin/dhclient/dhclient.c @@ -1,4 +1,4 @@ -/* $OpenBSD: dhclient.c,v 1.693 2021/02/15 19:33:21 krw Exp $ */ +/* $OpenBSD: dhclient.c,v 1.694 2021/02/19 13:46:59 krw Exp $ */ /* * Copyright 2004 Henning Brauer <henning@openbsd.org> @@ -138,6 +138,9 @@ void state_selecting(struct interface_info *); void state_bound(struct interface_info *); void state_panic(struct interface_info *); +void set_interval(struct interface_info *, time_t); +void set_secs(struct interface_info *, time_t); + void send_discover(struct interface_info *); void send_request(struct interface_info *); void send_decline(struct interface_info *); @@ -1416,6 +1419,58 @@ decline: return NULL; } +void +set_interval(struct interface_info *ifi, time_t cur_time) +{ + time_t interval = ifi->interval; + + if (interval == 0) { + if (ifi->state == S_REBOOTING) + interval = config->reboot_timeout; + else + interval = config->initial_interval; + } else { + interval += arc4random_uniform(2 * interval); + if (interval > config->backoff_cutoff) + interval = config->backoff_cutoff; + } + + switch (ifi->state) { + case S_REBOOTING: + case S_RENEWING: + if (cur_time + interval > ifi->expiry) + interval = ifi->expiry - cur_time; + break; + case S_REQUESTING: + if (cur_time + interval > ifi->first_sending + config->timeout) + interval = (ifi->first_sending + config->timeout) - cur_time; + break; + default: + break; + } + + if (cur_time < ifi->startup_time + config->link_timeout) + interval = 1; + + ifi->interval = interval ? interval : 1; +} + +void +set_secs(struct interface_info *ifi, time_t cur_time) +{ + time_t secs; + + if (ifi->state != S_REQUESTING) { + /* Update the number of seconds since we started sending. */ + secs = cur_time - ifi->first_sending; + if (secs > UINT16_MAX) + secs = UINT16_MAX; + ifi->secs = secs; + } + + ifi->sent_packet.secs = htons(ifi->secs); +} + /* * Send out a DHCPDISCOVER packet, and set a timeout to send out another * one after the right interval has expired. If we don't get an offer by @@ -1424,63 +1479,21 @@ decline: void send_discover(struct interface_info *ifi) { - struct dhcp_packet *packet = &ifi->sent_packet; - time_t cur_time, interval; + time_t cur_time; ssize_t rslt; time(&cur_time); - /* Figure out how long it's been since we started transmitting. */ - interval = cur_time - ifi->first_sending; - if (interval > config->timeout) { + if (log_getverbose()) + tick_msg("lease", TICK_WAIT); + + if (cur_time > ifi->first_sending + config->timeout) { state_panic(ifi); return; } - /* - * If we're supposed to increase the interval, do so. If it's - * currently zero (i.e., we haven't sent any packets yet), set - * it to initial_interval; otherwise, add to it a random - * number between zero and two times itself. On average, this - * means that it will double with every transmission. - */ - if (ifi->interval == 0) - ifi->interval = config->initial_interval; - else { - ifi->interval += arc4random_uniform(2 * ifi->interval); - } - - /* Don't backoff past cutoff. */ - if (ifi->interval > config->backoff_cutoff) - ifi->interval = config->backoff_cutoff; - - /* - * If the backoff would take us to the panic timeout, just use that - * as the interval. - */ - if (cur_time + ifi->interval > ifi->first_sending + config->timeout) - ifi->interval = (ifi->first_sending + - config->timeout) - cur_time + 1; - - /* - * If we are still starting up, backoff 1 second. If we are past - * link_timeout we just go daemon and finish things up in the - * background. - */ - if (cur_time < ifi->startup_time + config->link_timeout) { - if (log_getverbose() == 0) - tick_msg("lease", TICK_WAIT); - ifi->interval = 1; - } else { - tick_msg("lease", TICK_SLEEP); - } - - /* Record the number of seconds since we started sending. */ - if (interval < UINT16_MAX) - packet->secs = htons(interval); - else - packet->secs = htons(UINT16_MAX); - ifi->secs = packet->secs; + set_interval(ifi, cur_time); + set_secs(ifi, cur_time); rslt = send_packet(ifi, inaddr_any, inaddr_broadcast, "DHCPDISCOVER"); if (rslt != -1) @@ -1526,11 +1539,13 @@ send_request(struct interface_info *ifi) { struct sockaddr_in destination; struct in_addr from; - struct dhcp_packet *packet = &ifi->sent_packet; ssize_t rslt; time_t cur_time, interval; + cancel_timeout(ifi); time(&cur_time); + if (log_getverbose()) + tick_msg("lease", TICK_WAIT); /* Figure out how long it's been since we started transmitting. */ interval = cur_time - ifi->first_sending; @@ -1539,88 +1554,49 @@ send_request(struct interface_info *ifi) case S_REBOOTING: if (interval > config->reboot_timeout) ifi->state = S_INIT; + else { + destination.sin_addr.s_addr = INADDR_BROADCAST; + if (ifi->active == NULL) + from.s_addr = INADDR_ANY; + else + from.s_addr = ifi->active->address.s_addr; + } break; case S_RENEWING: if (cur_time > ifi->expiry) ifi->state = S_INIT; + else { + if (cur_time > ifi->rebind) + destination.sin_addr.s_addr = INADDR_BROADCAST; + else + destination.sin_addr.s_addr = ifi->destination.s_addr; + if (ifi->active == NULL) + from.s_addr = INADDR_ANY; + else + from.s_addr = ifi->active->address.s_addr; + } break; case S_REQUESTING: if (interval > config->timeout) ifi->state = S_INIT; + else { + destination.sin_addr.s_addr = INADDR_BROADCAST; + from.s_addr = INADDR_ANY; + } break; default: - /* Something has gone wrong. Start over. */ ifi->state = S_INIT; break; } + if (ifi->state == S_INIT) { - cancel_timeout(ifi); + /* Something has gone wrong. Start over. */ state_init(ifi); return; } - /* Do the exponential backoff. */ - if (ifi->interval == 0) { - if (ifi->state == S_REBOOTING) - ifi->interval = config->reboot_timeout; - else - ifi->interval = config->initial_interval; - } else - ifi->interval += arc4random_uniform(2 * ifi->interval); - - /* Don't backoff past cutoff. */ - if (ifi->interval > config->backoff_cutoff) - ifi->interval = config->backoff_cutoff; - - /* - * If the backoff would take us to the expiry time, just set the - * timeout to the expiry time. - */ - if (ifi->state != S_REQUESTING && cur_time + ifi->interval > - ifi->expiry) - ifi->interval = ifi->expiry - cur_time + 1; - - /* - * If we are still starting up, backoff 1 second. If we are past - * link_timeout we just go daemon and finish things up in the - * background. - */ - if (cur_time < ifi->startup_time + config->link_timeout) { - if (log_getverbose() == 0) - tick_msg("lease", TICK_SLEEP); - ifi->interval = 1; - } else { - tick_msg("lease", TICK_WAIT); - } - - /* - * If the reboot timeout has expired, or the lease rebind time has - * elapsed, or if we're not yet bound, broadcast the DHCPREQUEST rather - * than unicasting. - */ - memset(&destination, 0, sizeof(destination)); - if (ifi->state == S_REQUESTING || - ifi->state == S_REBOOTING || - cur_time > ifi->rebind || - interval > config->reboot_timeout) - destination.sin_addr.s_addr = INADDR_BROADCAST; - else - destination.sin_addr.s_addr = ifi->destination.s_addr; - - if (ifi->state != S_REQUESTING && ifi->active != NULL) - from.s_addr = ifi->active->address.s_addr; - else - from.s_addr = INADDR_ANY; - - /* Record the number of seconds since we started sending. */ - if (ifi->state == S_REQUESTING) - packet->secs = ifi->secs; - else { - if (interval < UINT16_MAX) - packet->secs = htons(interval); - else - packet->secs = htons(UINT16_MAX); - } + set_interval(ifi, cur_time); + set_secs(ifi, cur_time); rslt = send_packet(ifi, from, destination.sin_addr, "DHCPREQUEST"); if (rslt != -1) |