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1c7253726

Denys Vlasenko
Denys Vlasenko
2021-06-03
SUCCESS Duration: 154s

Subject

udhcpc[6]: when renewing, send 1 packet (not 3), on failure go back to BOUND

Binary

No binary (build failed)

Architecture & Compiler Flags

Architecture: x86_64-linux-gnu Compiler: gcc (Ubuntu 11.4.0-1ubuntu1~22.04.3) 11.4.0

—

Build Log

(log yok)

Commit Diff GitHub →

networking/udhcp/d6_dhcpc.c +26 -17networking/udhcp/dhcpc.c +28 -27
networking/udhcp/d6_dhcpc.c+26 -17
@@ -1420,7 +1420,7 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv)
retval = 1;
goto ret;
}
- /* wait before trying again */
+ /* Wait before trying again */
timeout = tryagain_timeout;
packet_num = 0;
continue;
@@ -1442,14 +1442,14 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv)
/* 1/2 lease passed, enter renewing state */
client_data.state = RENEWING;
client_data.first_secs = 0; /* make secs field count from 0 */
- change_listen_mode(LISTEN_KERNEL);
+ got_SIGUSR1:
log1s("entering renew state");
+ change_listen_mode(LISTEN_KERNEL);
/* fall right through */
- case RENEW_REQUESTED: /* manual (SIGUSR1) renew */
- case_RENEW_REQUESTED:
+ case RENEW_REQUESTED: /* in manual (SIGUSR1) renew */
case RENEWING:
- if (packet_num < 3) {
- /* send an unicast renew request */
+ if (packet_num == 0) {
+ /* Send an unicast renew request */
/* Sometimes observed to fail (EADDRNOTAVAIL) to bind
* a new UDP socket for sending inside send_renew.
* I hazard to guess existing listening socket
@@ -1463,13 +1463,18 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv)
else
send_d6_renew(xid, &srv6_buf, requested_ipv6);
timeout = discover_timeout;
- /* ^^^ used to be = lease_remaining / 2 - WAY too long */
packet_num++;
continue;
+ } /* else: we had sent one packet, but got no reply */
+ log1s("no response to renew");
+ if (lease_remaining > 30) {
+ /* Some lease time remains, try to renew later */
+ change_listen_mode(LISTEN_NONE);
+ goto BOUND_for_half_lease;
}
- /* Timed out, enter rebinding state */
- log1s("entering rebinding state");
+ /* Enter rebinding state */
client_data.state = REBINDING;
+ log1s("entering rebinding state");
/* Switch to bcast receive */
change_listen_mode(LISTEN_RAW);
packet_num = 0;
@@ -1509,8 +1514,14 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv)
/* Is it a signal? */
switch (udhcp_sp_read()) {
case SIGUSR1:
+ if (client_data.state <= REQUESTING)
+ /* Initial negotiations in progress, do not disturb */
+ break;
+
+ if (lease_remaining > 30) /* if renew fails, do not go back to BOUND */
+ lease_remaining = 30;
client_data.first_secs = 0; /* make secs field count from 0 */
- bb_simple_info_msg("performing DHCP renew");
+ packet_num = 0;
switch (client_data.state) {
/* Try to renew/rebind */
@@ -1519,21 +1530,19 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv)
case REBINDING:
change_listen_mode(LISTEN_KERNEL);
client_data.state = RENEW_REQUESTED;
- goto case_RENEW_REQUESTED;
+ goto got_SIGUSR1;
- /* Start things over */
- case RENEW_REQUESTED: /* two or more SIGUSR1 received */
+ /* Two SIGUSR1 received, start things over */
+ case RENEW_REQUESTED:
change_listen_mode(LISTEN_NONE);
d6_run_script_no_option("deconfig");
+ /* Wake from SIGUSR2-induced deconfigured state */
default:
- /* case REQUESTING: */
/* case RELEASED: */
- /* case INIT_SELECTING: */
change_listen_mode(LISTEN_NONE);
}
client_data.state = INIT_SELECTING;
- packet_num = 0;
/* Kill any timeouts, user wants this to hurry along */
timeout = 0;
continue;
@@ -1830,7 +1839,7 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv)
}
#endif
-// BOUND_for_half_lease:
+ BOUND_for_half_lease:
timeout = (unsigned)lease_remaining / 2;
client_data.state = BOUND;
packet_num = 0;
networking/udhcp/dhcpc.c+28 -27
@@ -1480,7 +1480,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
retval = 1;
goto ret;
}
- /* wait before trying again */
+ /* Wait before trying again */
timeout = tryagain_timeout;
packet_num = 0;
continue;
@@ -1502,14 +1502,14 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
/* 1/2 lease passed, enter renewing state */
client_data.state = RENEWING;
client_data.first_secs = 0; /* make secs field count from 0 */
- change_listen_mode(LISTEN_KERNEL);
+ got_SIGUSR1:
log1s("entering renew state");
+ change_listen_mode(LISTEN_KERNEL);
/* fall right through */
- case RENEW_REQUESTED: /* manual (SIGUSR1) renew */
- case_RENEW_REQUESTED:
+ case RENEW_REQUESTED: /* in manual (SIGUSR1) renew */
case RENEWING:
- if (packet_num < 3) {
- /* send an unicast renew request */
+ if (packet_num == 0) {
+ /* Send an unicast renew request */
/* Sometimes observed to fail (EADDRNOTAVAIL) to bind
* a new UDP socket for sending inside send_renew.
* I hazard to guess existing listening socket
@@ -1520,7 +1520,6 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
*/
if (send_renew(xid, server_addr, requested_ip) >= 0) {
timeout = discover_timeout;
- /* ^^^ used to be = lease_remaining / 2 - WAY too long */
packet_num++;
continue;
}
@@ -1529,15 +1528,16 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
* which gave us bogus server ID 1.1.1.1
* which wasn't reachable (and probably did not exist).
*/
+ } /* else: we had sent one packet, but got no reply */
+ log1s("no response to renew");
+ if (lease_remaining > 30) {
+ /* Some lease time remains, try to renew later */
+ change_listen_mode(LISTEN_NONE);
+ goto BOUND_for_half_lease;
}
-//TODO: if 3 renew's failed (no reply) but remaining lease is large enough,
-//it might make sense to go back to BOUND and try later? a-la
-// if (lease_remaining > 30) change_listen_mode(LISTEN_NONE) + goto BOUND_for_half_lease;
-//If we do that, "packet_num < 3" test below might be superfluous
-//(lease_remaining will run out anyway)
- /* Timed out or error, enter rebinding state */
- log1s("entering rebinding state");
+ /* Enter rebinding state */
client_data.state = REBINDING;
+ log1s("entering rebinding state");
/* Switch to bcast receive */
change_listen_mode(LISTEN_RAW);
packet_num = 0;
@@ -1575,31 +1575,34 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
/* Is it a signal? */
switch (udhcp_sp_read()) {
case SIGUSR1:
+ if (client_data.state <= REQUESTING)
+ /* Initial negotiations in progress, do not disturb */
+ break;
+
+ if (lease_remaining > 30) /* if renew fails, do not go back to BOUND */
+ lease_remaining = 30;
client_data.first_secs = 0; /* make secs field count from 0 */
- bb_simple_info_msg("performing DHCP renew");
+ packet_num = 0;
switch (client_data.state) {
/* Try to renew/rebind */
case BOUND:
case RENEWING:
case REBINDING:
- change_listen_mode(LISTEN_KERNEL);
client_data.state = RENEW_REQUESTED;
- goto case_RENEW_REQUESTED;
+ goto got_SIGUSR1;
- /* Start things over */
- case RENEW_REQUESTED: /* two or more SIGUSR1 received */
+ /* Two SIGUSR1 received, start things over */
+ case RENEW_REQUESTED:
change_listen_mode(LISTEN_NONE);
udhcp_run_script(NULL, "deconfig");
+ /* Wake from SIGUSR2-induced deconfigured state */
default:
- /* case REQUESTING: */
/* case RELEASED: */
- /* case INIT_SELECTING: */
change_listen_mode(LISTEN_NONE);
}
client_data.state = INIT_SELECTING;
- packet_num = 0;
/* Kill any timeouts, user wants this to hurry along */
timeout = 0;
continue;
@@ -1723,10 +1726,9 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
strcpy(server_str, inet_ntoa(temp_addr));
temp_addr.s_addr = packet.yiaddr;
+ lease_remaining = 60 * 60;
temp = udhcp_get_option32(&packet, DHCP_LEASE_TIME);
- if (!temp) {
- lease_remaining = 60 * 60;
- } else {
+ if (temp) {
uint32_t lease;
/* it IS unaligned sometimes, don't "optimize" */
move_from_unaligned32(lease, temp);
@@ -1798,8 +1800,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
opt = ((opt & ~OPT_b) | OPT_f);
}
#endif
-
-// BOUND_for_half_lease:
+ BOUND_for_half_lease:
timeout = (unsigned)lease_remaining / 2;
client_data.state = BOUND;
/* make future renew packets use different xid */