From 2812dc92859ab0dc095d38494d651bd83f3c1dc5 Mon Sep 17 00:00:00 2001 From: Darren Tucker Date: Wed, 21 Mar 2007 20:45:06 +1100 Subject: - dtucker@cvs.openbsd.org 2007/03/19 12:16:42 [ssh-agent.c] Remove the signal handler that checks if the agent's parent process has gone away, instead check when the select loop returns. Record when the next key will expire when scanning for expired keys. Set the select timeout to whichever of these two things happens next. With djm@, with & ok deraadt@ markus@ --- ChangeLog | 9 ++++++++- ssh-agent.c | 66 ++++++++++++++++++++++++++++++++++++++----------------------- 2 files changed, 49 insertions(+), 26 deletions(-) diff --git a/ChangeLog b/ChangeLog index fe50bc568..baa58bc8a 100644 --- a/ChangeLog +++ b/ChangeLog @@ -12,6 +12,13 @@ a configuration override. In the future, we will change the server's default itself so users who need the legacy protocol will need to turn it on explicitly + - dtucker@cvs.openbsd.org 2007/03/19 12:16:42 + [ssh-agent.c] + Remove the signal handler that checks if the agent's parent process + has gone away, instead check when the select loop returns. Record when + the next key will expire when scanning for expired keys. Set the select + timeout to whichever of these two things happens next. With djm@, with & + ok deraadt@ markus@ 20070313 - (dtucker) [entropy.c scard-opensc.c ssh-rand-helper.c] Bug #1294: include @@ -2841,4 +2848,4 @@ OpenServer 6 and add osr5bigcrypt support so when someone migrates passwords between UnixWare and OpenServer they will still work. OK dtucker@ -$Id: ChangeLog,v 1.4642 2007/03/21 09:42:24 dtucker Exp $ +$Id: ChangeLog,v 1.4643 2007/03/21 09:45:06 dtucker Exp $ diff --git a/ssh-agent.c b/ssh-agent.c index a3a867c33..c3d5e5a75 100644 --- a/ssh-agent.c +++ b/ssh-agent.c @@ -1,4 +1,4 @@ -/* $OpenBSD: ssh-agent.c,v 1.154 2007/02/28 00:55:30 dtucker Exp $ */ +/* $OpenBSD: ssh-agent.c,v 1.155 2007/03/19 12:16:42 dtucker Exp $ */ /* * Author: Tatu Ylonen * Copyright (c) 1995 Tatu Ylonen , Espoo, Finland @@ -120,6 +120,7 @@ int max_fd = 0; /* pid of shell == parent of agent */ pid_t parent_pid = -1; +u_int parent_alive_interval = 0; /* pathname and directory for AUTH_SOCKET */ char socket_name[MAXPATHLEN]; @@ -421,10 +422,11 @@ process_remove_all_identities(SocketEntry *e, int version) buffer_put_char(&e->output, SSH_AGENT_SUCCESS); } -static void +/* removes expired keys and returns number of seconds until the next expiry */ +static u_int reaper(void) { - u_int now = time(NULL); + u_int deadline = 0, now = time(NULL); Identity *id, *nxt; int version; Idtab *tab; @@ -433,14 +435,22 @@ reaper(void) tab = idtab_lookup(version); for (id = TAILQ_FIRST(&tab->idlist); id; id = nxt) { nxt = TAILQ_NEXT(id, next); - if (id->death != 0 && now >= id->death) { + if (id->death == 0) + continue; + if (now >= id->death) { debug("expiring key '%s'", id->comment); TAILQ_REMOVE(&tab->idlist, id, next); free_identity(id); tab->nentries--; - } + } else + deadline = (deadline == 0) ? id->death : + MIN(deadline, id->death); } } + if (deadline == 0 || deadline <= now) + return 0; + else + return (deadline - now); } static void @@ -826,10 +836,12 @@ new_socket(sock_type type, int fd) } static int -prepare_select(fd_set **fdrp, fd_set **fdwp, int *fdl, u_int *nallocp) +prepare_select(fd_set **fdrp, fd_set **fdwp, int *fdl, u_int *nallocp, + struct timeval **tvpp) { - u_int i, sz; + u_int i, sz, deadline; int n = 0; + static struct timeval tv; for (i = 0; i < sockets_alloc; i++) { switch (sockets[i].type) { @@ -873,6 +885,17 @@ prepare_select(fd_set **fdrp, fd_set **fdwp, int *fdl, u_int *nallocp) break; } } + deadline = reaper(); + if (parent_alive_interval != 0) + deadline = (deadline == 0) ? parent_alive_interval : + MIN(deadline, parent_alive_interval); + if (deadline == 0) { + *tvpp = NULL; + } else { + tv.tv_sec = deadline; + tv.tv_usec = 0; + *tvpp = &tv; + } return (1); } @@ -980,19 +1003,14 @@ cleanup_handler(int sig) _exit(2); } -/*ARGSUSED*/ static void -check_parent_exists(int sig) +check_parent_exists(void) { - int save_errno = errno; - if (parent_pid != -1 && kill(parent_pid, 0) < 0) { /* printf("Parent has died - Authentication agent exiting.\n"); */ - cleanup_handler(sig); /* safe */ + cleanup_socket(); + _exit(2); } - mysignal(SIGALRM, check_parent_exists); - alarm(10); - errno = save_errno; } static void @@ -1027,7 +1045,7 @@ main(int ac, char **av) extern char *optarg; pid_t pid; char pidstrbuf[1 + 3 * sizeof pid]; - struct timeval tv; + struct timeval *tvp = NULL; /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ sanitise_stdfd(); @@ -1228,10 +1246,8 @@ main(int ac, char **av) skip: new_socket(AUTH_SOCKET, sock); - if (ac > 0) { - mysignal(SIGALRM, check_parent_exists); - alarm(10); - } + if (ac > 0) + parent_alive_interval = 10; idtab_init(); if (!d_flag) signal(SIGINT, SIG_IGN); @@ -1241,12 +1257,12 @@ skip: nalloc = 0; while (1) { - tv.tv_sec = 10; - tv.tv_usec = 0; - prepare_select(&readsetp, &writesetp, &max_fd, &nalloc); - result = select(max_fd + 1, readsetp, writesetp, NULL, &tv); + prepare_select(&readsetp, &writesetp, &max_fd, &nalloc, &tvp); + result = select(max_fd + 1, readsetp, writesetp, NULL, tvp); saved_errno = errno; - reaper(); /* remove expired keys */ + if (parent_alive_interval != 0) + check_parent_exists(); + (void) reaper(); /* remove expired keys */ if (result < 0) { if (saved_errno == EINTR) continue; -- cgit v1.2.3