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path: root/networking/udhcp/dhcpd.c
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2018-03-11udhcpd: clamp down huge auto_times to ~2M seconds, better EINTR poll handlingDenys Vlasenko
EINTR _should_ only happen on two signals we trap, and safe_poll _should_ work here just fine, but there were kernel bugs where spurious EINTRs happen (e.g. on ptrace attach). Be safe. function old new delta udhcpd_main 1437 1468 +31 Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2018-03-10udhcpd: fix "not dying on SIGTERM"Denys Vlasenko
Fixes: commit 52a515d18724bbb34e3ccbbb0218efcc4eccc0a8 "udhcp: use poll() instead of select()" Feb 16 2017 udhcp_sp_read() is meant to check whether signal pipe indeed has some data to read. In the above commit, it was changed as follows: - if (!FD_ISSET(signal_pipe.rd, rfds)) + if (!pfds[0].revents) return 0; The problem is, the check was working for select() purely by accident. Caught signal interrupts select()/poll() syscalls, they return with EINTR (regardless of SA_RESTART flag in sigaction). _Then_ signal handler is invoked. IOW: they can't see any changes to fd state caused by signal haldler (in our case, signal handler makes signal pipe ready to be read). For select(), it means that rfds[] bit array is unmodified, bit of signal pipe's read fd is still set, and the above check "works": it thinks select() says there is data to read. This accident does not work for poll(): .revents stays clear, and we do not try reading signal pipe as we should. In udhcpd, we fall through and block in socket read. Further SIGTERM signals simply cause socket read to be interrupted and then restarted (since SIGTERM handler has SA_RESTART=1). Fixing this as follows: remove the check altogether. Set signal pipe read fd to nonblocking mode. Always read it in udhcp_sp_read(). If read fails, assume it's EAGAIN and return 0 ("no signal seen"). udhcpd avoids reading signal pipe on every recvd packet by looping if EINTR (using safe_poll()) - thus ensuring we have correct .revents for all fds - and calling udhcp_sp_read() only if pfds[0].revents!=0. udhcpc performs much fewer reads (typically it sleeps >99.999% of the time), there is no need to optimize it: can call udhcp_sp_read() after each poll unconditionally. To robustify socket reads, unconditionally set pfds[1].revents=0 in udhcp_sp_fd_set() (which is before poll), and check it before reading network socket in udhcpd. TODO: This might still fail: if pfds[1].revents=POLLIN, socket read may still block. There are rare cases when select/poll indicates that data can be read, but then actual read still blocks (one such case is UDP packets with wrong checksum). General advise is, if you use a poll/select loop, keep all your fds nonblocking. Maybe we should also do that to our network sockets? function old new delta udhcp_sp_setup 55 65 +10 udhcp_sp_fd_set 54 60 +6 udhcp_sp_read 46 36 -10 udhcpd_main 1451 1437 -14 udhcpc_main 2723 2708 -15 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 2/3 up/down: 16/-39) Total: -23 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2018-02-07udhcp: do not setlinebuf(stdout), we don't print to stdout anymoreDenys Vlasenko
Since bb_info_msg() was eliminated type of buffering on stdout is not important function old new delta udhcpd_main 1463 1451 -12 udhcpc_main 2735 2723 -12 setlinebuf 19 - -19 ------------------------------------------------------------------------------ (add/remove: 0/2 grow/shrink: 0/2 up/down: 0/-43) Total: -43 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2018-02-01udhcpd: use ptr_to_globals for its lone global data (g_leases)Denys Vlasenko
function old new delta udhcpd_main 1461 1463 +2 add_lease 320 318 -2 g_leases 4 - -4 write_leases 223 214 -9 ------------------------------------------------------------------------------ (add/remove: 0/1 grow/shrink: 1/2 up/down: 2/-15) Total: -13 bytes text data bss dec hex filename 933232 481 6856 940569 e5a19 busybox_old 933223 481 6852 940556 e5a0c busybox_unstripped Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-09-29use %m printf specifier where appropriateDenys Vlasenko
function old new delta out 85 75 -10 udhcpd_main 1472 1461 -11 open_stdio_to_tty 98 85 -13 init_exec 245 232 -13 udhcpc_main 2763 2749 -14 do_cmd 4771 4755 -16 status_line_bold_errno 32 14 -18 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 0/7 up/down: 0/-95) Total: -95 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-09-29udhcpc: paranoia when using kernel UDP mode for sending renew: server ID may ↵Denys Vlasenko
be bogus With new code, we request that target IP (server ID) must be directly reachable. If it's not, this happens: udhcpc: waiting 2000 seconds udhcpc: entering listen mode: kernel udhcpc: opening listen socket on *:68 wlan0 udhcpc: entering renew state udhcpc: sending renew to 1.1.1.1 udhcpc: send: Network is unreachable ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 1.1.1.1 needs routing, this is fishy! udhcpc: entering rebinding state udhcpc: entering listen mode: raw udhcpc: created raw socket udhcpc: sending renew to 0.0.0.0 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ going to use broadcast which is the desired behavior. Before the patch, packet to 1.1.1.1 was routed over eth0 (!) and maybe even into Internet (!!!). function old new delta udhcpc_main 2752 2763 +11 udhcp_send_kernel_packet 295 301 +6 send_renew 82 84 +2 send_packet 166 168 +2 bcast_or_ucast 23 25 +2 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 5/0 up/down: 23/0) Total: 23 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-08-08getopt32: remove opt_complementaryDenys Vlasenko
function old new delta vgetopt32 1318 1392 +74 runsvdir_main 703 713 +10 bb_make_directory 423 425 +2 collect_cpu 546 545 -1 opt_chars 3 - -3 opt_complementary 4 - -4 tftpd_main 567 562 -5 ntp_init 476 471 -5 zcip_main 1266 1256 -10 xxd_main 428 418 -10 whois_main 140 130 -10 who_main 463 453 -10 which_main 212 202 -10 wget_main 2535 2525 -10 watchdog_main 291 281 -10 watch_main 222 212 -10 vlock_main 399 389 -10 uuencode_main 332 322 -10 uudecode_main 316 306 -10 unlink_main 45 35 -10 udhcpd_main 1482 1472 -10 udhcpc_main 2762 2752 -10 tune2fs_main 290 280 -10 tunctl_main 366 356 -10 truncate_main 218 208 -10 tr_main 518 508 -10 time_main 1134 1124 -10 tftp_main 286 276 -10 telnetd_main 1873 1863 -10 tcpudpsvd_main 1785 1775 -10 taskset_main 521 511 -10 tar_main 1009 999 -10 tail_main 1644 1634 -10 syslogd_main 1967 1957 -10 switch_root_main 368 358 -10 svlogd_main 1454 1444 -10 sv 1296 1286 -10 stat_main 104 94 -10 start_stop_daemon_main 1028 1018 -10 split_main 542 532 -10 sort_main 796 786 -10 slattach_main 624 614 -10 shuf_main 504 494 -10 setsid_main 96 86 -10 setserial_main 1132 1122 -10 setfont_main 388 378 -10 setconsole_main 78 68 -10 sendmail_main 1209 1199 -10 sed_main 677 667 -10 script_main 1077 1067 -10 run_parts_main 325 315 -10 rtcwake_main 454 444 -10 rm_main 175 165 -10 reformime_main 119 109 -10 readlink_main 123 113 -10 rdate_main 246 236 -10 pwdx_main 189 179 -10 pstree_main 317 307 -10 pscan_main 663 653 -10 popmaildir_main 818 808 -10 pmap_main 80 70 -10 nc_main 1042 1032 -10 mv_main 558 548 -10 mountpoint_main 477 467 -10 mount_main 1264 1254 -10 modprobe_main 768 758 -10 modinfo_main 333 323 -10 mktemp_main 200 190 -10 mkswap_main 324 314 -10 mkfs_vfat_main 1489 1479 -10 microcom_main 715 705 -10 md5_sha1_sum_main 521 511 -10 man_main 867 857 -10 makedevs_main 1052 1042 -10 ls_main 563 553 -10 losetup_main 432 422 -10 loadfont_main 89 79 -10 ln_main 524 514 -10 link_main 75 65 -10 ipcalc_main 544 534 -10 iostat_main 2397 2387 -10 install_main 768 758 -10 id_main 480 470 -10 i2cset_main 1239 1229 -10 i2cget_main 380 370 -10 i2cdump_main 1482 1472 -10 i2cdetect_main 682 672 -10 hwclock_main 406 396 -10 httpd_main 741 731 -10 grep_main 837 827 -10 getty_main 1559 1549 -10 fuser_main 297 287 -10 ftpgetput_main 345 335 -10 ftpd_main 2232 2222 -10 fstrim_main 251 241 -10 fsfreeze_main 77 67 -10 fsck_minix_main 2921 2911 -10 flock_main 314 304 -10 flashcp_main 740 730 -10 flash_eraseall_main 833 823 -10 fdformat_main 532 522 -10 expand_main 680 670 -10 eject_main 335 325 -10 dumpleases_main 630 620 -10 du_main 314 304 -10 dos2unix_main 441 431 -10 diff_main 1350 1340 -10 df_main 1064 1054 -10 date_main 1095 1085 -10 cut_main 961 951 -10 cryptpw_main 228 218 -10 crontab_main 575 565 -10 crond_main 1149 1139 -10 cp_main 370 360 -10 common_traceroute_main 3834 3824 -10 common_ping_main 1767 1757 -10 comm_main 239 229 -10 cmp_main 655 645 -10 chrt_main 379 369 -10 chpst_main 704 694 -10 chpasswd_main 308 298 -10 chown_main 171 161 -10 chmod_main 158 148 -10 cat_main 428 418 -10 bzip2_main 120 110 -10 blkdiscard_main 264 254 -10 base64_main 221 211 -10 arping_main 1665 1655 -10 ar_main 556 546 -10 adjtimex_main 406 396 -10 adduser_main 882 872 -10 addgroup_main 411 401 -10 acpid_main 1198 1188 -10 optstring 11 - -11 opt_string 18 - -18 OPT_STR 25 - -25 ubi_tools_main 1288 1258 -30 ls_options 31 - -31 ------------------------------------------------------------------------------ (add/remove: 0/6 grow/shrink: 3/129 up/down: 86/-1383) Total: -1297 bytes text data bss dec hex filename 915428 485 6876 922789 e14a5 busybox_old 914629 485 6872 921986 e1182 busybox_unstripped Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-06-28udhcpc6: make -O OPT workDenys Vlasenko
Patch is based on work by tiggerswelt.net. Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-02-16udhcp: use poll() instead of select()Denys Vlasenko
function old new delta udhcp_sp_read 65 46 -19 udhcp_sp_fd_set 79 54 -25 udhcpd_main 1530 1482 -48 udhcpc_main 2780 2730 -50 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 0/4 up/down: 0/-142) Total: -142 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2016-11-23Convert all udhcp applets to "new style" applet definitionsDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2016-10-04dhcp: merge leases.c and static_leases.c into dhcpd.cDenys Vlasenko
function old new delta send_offer 292 461 +169 udhcpd_main 1531 1588 +57 read_leases 330 332 +2 add_lease 314 312 -2 find_lease_by_mac 68 - -68 find_free_or_expired_nip 174 - -174 ------------------------------------------------------------------------------ (add/remove: 0/4 grow/shrink: 3/1 up/down: 228/-244) Total: -16 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2016-10-04dhcp: merge most of static_leases.c into dhcpd.cDenys Vlasenko
function old new delta read_staticlease 121 222 +101 add_static_lease 48 - -48 log_static_leases 68 - -68 ------------------------------------------------------------------------------ (add/remove: 0/2 grow/shrink: 1/0 up/down: 101/-116) Total: -15 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2016-10-04dhcp: merge files.c into dhcpd.cDenys Vlasenko
Added NOINLINE to two function, since my version of gcc would actualy increase code size otherwise. I see no size changes. Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2016-04-21udhcp: add setup_common_bufsiz() as neededDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2016-03-30dhcpd: string reuseDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2016-03-30udhcp: get rid of bb_info_msg()Denys Vlasenko
function old new delta udhcpd_main 1501 1531 +30 d6_recv_raw_packet 251 264 +13 perform_d6_release 188 198 +10 udhcpc6_main 2443 2449 +6 udhcp_recv_raw_packet 582 588 +6 udhcp_recv_kernel_packet 132 138 +6 send_d6_renew 140 146 +6 d6_recv_kernel_packet 118 124 +6 send_renew 77 82 +5 send_discover 85 90 +5 send_decline 84 89 +5 send_d6_select 97 102 +5 send_d6_discover 174 179 +5 perform_release 167 172 +5 count_lines 72 74 +2 udhcpc_main 2836 2837 +1 bb_info_msg 125 - -125 ------------------------------------------------------------------------------ (add/remove: 0/2 grow/shrink: 17/4 up/down: 117/-180) Total: -63 bytes text data bss dec hex filename 924935 906 17160 943001 e6399 busybox_old 924736 906 17160 942802 e62d2 busybox_unstripped Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2015-01-27dhcpd: fix an improper widening conversionDenys Vlasenko
We wanted to detect when tv_sec = unsigned1 - unsigned2 underflows by looking at tv_sec's sign. But if tv_sec is long and it is wider than unsigned, we get unsigned -> long conversion which is in this case never negative. Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2014-10-30udhcpd: add option for tweaking arppingMichel Stam
Some clients have a very short timeout for sending the DHCP DISCOVER, shorter than the arpping timeout of 2000 milliseconds that udhcpd uses by default. This patch allows tweaking the timeout, or disabling of arpping altogether, at the risk of handing out addresses which are already in use. function old new delta udhcpd_main 1460 1501 +41 udhcpc_main 2814 2851 +37 packed_usage 29957 29974 +17 arpping 477 493 +16 find_free_or_expired_nip 161 174 +13 send_offer 285 292 +7 nobody_responds_to_arp 85 89 +4 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 7/0 up/down: 135/0) Total: 135 bytes Signed-off-by: Michel Stam <m.stam@fugro.nl> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2013-03-14udhcpd: also add -I ADDR to help textDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2013-03-13udhcpd: add -I LOCAL_ADDR optionDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2012-07-24dhcpd: write lease file on exitDenys Vlasenko
function old new delta udhcpd_main 1431 1403 -28 Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2011-10-18udhcp: IF_UDHCP_VERBOSE() macro - improve code readabilityLeonid Lisovskiy
Signed-off-by: Leonid Lisovskiy <lly.dev@gmail.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2011-04-11move remaining help text from include/usage.src.hPere Orga
Signed-off-by: Pere Orga <gotrunks@gmail.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2010-11-28dhcpd: reply with NAK to clients in INIT-REBOOT state w/o existing leaseDenys Vlasenko
We were not responding to them at all. Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2010-11-28dhcpd: smaller code: do not look for REQUESTED_IP twiceDenys Vlasenko
text data bss dec hex filename 883235 936 17192 901363 dc0f3 busybox_old 883219 936 17192 901347 dc0e3 busybox_unstripped Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2010-10-28*: whitespace fixesDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2010-10-21udhcpd: reduce stack usage by ~700 bytes. +28 bytes code sizeDenys Vlasenko
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
2010-06-04udhcpd: fix daemonize crash on nommu systemsMike Frysinger
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2010-04-04udhcpd: note missing sanity checks on INFORM message handlingDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2010-03-27udhcpd: fix -v/-P mixupDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2010-03-26udhcp: cosmetic cleanups; one case of s/full_read/xread/Denys Vlasenko
function old new delta dumpleases_main 632 623 -9 Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2010-03-26udhcp: pass pointer to whole packet to "add option" functionsDenys Vlasenko
This is needed for "overflow option" support function old new delta udhcp_find_option - 34 +34 udhcp_add_binary_option 94 106 +12 write_leases 227 223 -4 udhcp_init_header 86 82 -4 send_release 104 99 -5 init_packet 87 81 -6 add_client_options 160 154 -6 add_server_options 100 92 -8 udhcpd_main 1964 1954 -10 udhcpc_main 2859 2837 -22 find_option 34 - -34 ------------------------------------------------------------------------------ (add/remove: 1/1 grow/shrink: 1/8 up/down: 46/-99) Total: -53 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2010-03-26udhcp: move options.c to common.c; disable unused bool and s16 option codeDenys Vlasenko
function old new delta udhcp_add_binary_option - 94 +94 udhcp_str2nip - 42 +42 len_of_option_as_string 12 10 -2 dhcp_option_lengths 12 10 -2 udhcpc_main 2859 2851 -8 read_nip 42 - -42 xmalloc_optname_optval 590 536 -54 udhcp_str2optset 443 366 -77 udhcp_add_option_string 86 - -86 ------------------------------------------------------------------------------ (add/remove: 2/2 grow/shrink: 0/5 up/down: 136/-271) Total: -135 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2010-03-23*: merge some common stringsDenys Vlasenko
text data bss dec hexfilename 838650 8009 0 846659 ceb43busybox_old 838519 8009 0 846528 ceac0busybox_unstripped Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2010-03-22udhcp: merge options.h into common.h, script.c into dhcpc.cDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2010-03-21dhcpd: apparently, sometimes IP is in ciaddr, not requested_ip...Denys Vlasenko
also revert the part which appempted to "fix" that in client function old new delta udhcpd_main 1949 1964 +15 send_renew 142 105 -37 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 1/1 up/down: 15/-37) Total: -22 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2010-03-21udhcpd: untangle incredibly messy handling of DHCPREQUESTDenys Vlasenko
Also fixes attacks possible via DHCPDECLINE / DHCPRELEASE function old new delta udhcpd_main 1846 1949 +103 send_renew 105 142 +37 send_NAK 61 - -61 send_ACK 180 - -180 ------------------------------------------------------------------------------ (add/remove: 0/2 grow/shrink: 2/0 up/down: 140/-241) Total: -101 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2010-03-21udhcp: tweak udhcpd.conf example and comments. no code changesDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2010-03-21udhcp: code shrink; disable time and log server optionsDenys Vlasenko
function old new delta add_server_options - 100 +100 udhcp_add_simple_option 92 90 -2 nobody_responds_to_arp 88 85 -3 dhcp_options 66 62 -4 udhcp_add_option_string 104 94 -10 udhcp_run_script 665 654 -11 dhcp_option_strings 203 188 -15 static.blank_chaddr 16 - -16 send_ACK 211 180 -31 add_bootp_options 61 - -61 udhcpd_main 1925 1846 -79 ------------------------------------------------------------------------------ (add/remove: 1/2 grow/shrink: 0/8 up/down: 100/-232) Total: -132 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2010-03-20udhcpd: remove redundant code in send_offer()Denys Vlasenko
static_lease_nip and lease pointer are canculated in the caller, no need to calculate them again. lease_time_sec calculation is also redundant: it is assigned to later, w/o being used in between. function old new delta udhcpd_main 1956 1925 -31 Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2010-03-20udhcp: move serverpacket.c into dhcpd.c, no other changesDenys Vlasenko
function old new delta udhcpd_main 1480 1956 +476 send_inform 83 - -83 send_offer 376 - -376 ------------------------------------------------------------------------------ (add/remove: 0/3 grow/shrink: 1/0 up/down: 476/-459) Total: 17 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2009-11-13*: use "can't" instead of "cannot"Denys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2009-06-17udhcp: logging improvements, field and variable renamesDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2009-06-17udhcp: shorten mac len from 16 to 6 in lease fileDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2009-06-17udhcp: change UDHCP_DEBUG into int, make verbosity selectable with -vDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2009-06-16udhcp: rename server/client_config.arp to server_mac and client_macDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2009-06-16udhcp: cleanup of static lease handlingDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2009-06-16udhcp: rename giaddr to gateway_nip and server to server_nipDenys Vlasenko
"nip" stands for "IP in network order" Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2009-06-16udhcp: rename fields in struct dhcpOfferedAddrDenys Vlasenko
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2009-04-21*: mass renaming of USE_XXXX to IF_XXXXDenis Vlasenko
and SKIP_XXXX to IF_NOT_XXXX - the second one was especially badly named. It was not skipping anything!
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-22 04:00:11 +0000