rsh vs net/ipcad - problems on 5.5
I encountered a strange problem when trying to communicate with net/ipcad: rsh localhost stats rsh: poll: Undefined error: 0 Same thing on 5.1: rsh localhost stats connect to address ::1: Connection refused Trying 127.0.0.1... Interface vlan123: received 585816944, 5 m average 313 bytes/sec, 4 pkts/sec, dropped 6078 Flow entries made: 583 Memory usage: 6% (65296 from 1048576) Free slots for rsh clients: 9 IPCAD uptime is 159 days 7:04 fw.example.com uptime is 159 days 7:04 According to sthen@ this also works fine on 5.4 and he suspects breakage due to time_t changes. He also provided simple sample config http://pbot.rmdir.de/iFGRSOehzxnZ1flTJqum5Q because he's awesome like that ;) kern.version=OpenBSD 5.5 (GENERIC.MP) #0: Fri Apr 25 13:03:34 CEST 2014 r...@stable-55-amd64.mtier.org:/binpatchng/work-binpatch55-amd64/src/sys/arch/amd64/compile/GENERIC.MP ipcad-3.7.3p1 -- viq
Re: rsh vs net/ipcad - problems on 5.5
On 2014/05/20 16:41, viq wrote:
I encountered a strange problem when trying to communicate with net/ipcad:
rsh localhost stats
rsh: poll: Undefined error: 0
Same thing on 5.1:
rsh localhost stats
connect to address ::1: Connection refused
Trying 127.0.0.1...
Interface vlan123: received 585816944, 5 m average 313 bytes/sec, 4
pkts/sec, dropped 6078
Flow entries made: 583
Memory usage: 6% (65296 from 1048576)
Free slots for rsh clients: 9
IPCAD uptime is 159 days 7:04
fw.example.com uptime is 159 days 7:04
According to sthen@ this also works fine on 5.4 and he suspects
breakage due to time_t changes. He also provided simple sample config
http://pbot.rmdir.de/iFGRSOehzxnZ1flTJqum5Q because he's awesome like
that ;)
kern.version=OpenBSD 5.5 (GENERIC.MP) #0: Fri Apr 25 13:03:34 CEST 2014
r...@stable-55-amd64.mtier.org:/binpatchng/work-binpatch55-amd64/src/sys/arch/amd64/compile/GENERIC.MP
ipcad-3.7.3p1
--
viq
Note that ipcad listens on port 514 and provides *its own* cisco-ish
rshell interface that you connect to, this isn't about openbsd rshd.
Sample config inline at the bottom of this mail. (the pastebin above
was just meant for when I was talking about this on irc - it will expire).
The error is coming from /usr/src/usr.bin/rsh/rsh.c:243 and since
nothing changed here in many years, I'm wondering if there's anything
up with poll(2). (If it's a direct bug with rsh, well, that's fixed
a different way in -current)..
230 sigprocmask(SIG_SETMASK, omask, NULL);
231 pfd[1].fd = rfd2;
232 pfd[1].events = POLLIN;
233 pfd[0].fd = rem;
234 pfd[0].events = POLLIN;
235 do {
236 if (poll(pfd, 2, INFTIM) 0) {
237 if (errno != EINTR)
238 err(1, poll);
239 continue;
240 }
241 if ((pfd[0].revents (POLLERR|POLLHUP|POLLNVAL)) ||
242 (pfd[1].revents (POLLERR|POLLHUP|POLLNVAL)))
243 err(1, poll);
244 if (pfd[1].revents POLLIN) {
245 errno = 0;
246 cc = read(rfd2, buf, sizeof buf);
247 if (cc = 0) {
248 if (errno != EWOULDBLOCK)
249 pfd[1].revents = 0;
250 } else
251 (void)write(STDERR_FILENO, buf, cc);
252 }
253 if (pfd[0].revents POLLIN) {
254 errno = 0;
255 cc = read(rem, buf, sizeof buf);
256 if (cc = 0) {
257 if (errno != EWOULDBLOCK)
258 pfd[0].revents = 0;
259 } else
260 (void)write(STDOUT_FILENO, buf, cc);
261 }
262 } while ((pfd[0].revents POLLIN) || (pfd[1].revents POLLIN));
===
capture-ports disable;
interface em0;
rsh enable at 127.0.0.1;
rsh root@127.0.0.1 admin;
rsh 127.0.0.1;
rsh ttl = 3;
rsh timeout = 30;
dumpfile = ipcad.dump;
chroot = /var/ipcad;
pidfile = ipcad.pid;
memory_limit = 1m;
Re: rsh vs net/ipcad - problems on 5.5
On Tue, May 20, 2014 at 8:29 AM, Stuart Henderson st...@openbsd.org wrote: On 2014/05/20 16:41, viq wrote: I encountered a strange problem when trying to communicate with net/ipcad: rsh localhost stats rsh: poll: Undefined error: 0 ... Note that ipcad listens on port 514 and provides *its own* cisco-ish rshell interface that you connect to, this isn't about openbsd rshd. The error is coming from /usr/src/usr.bin/rsh/rsh.c:243 and since nothing changed here in many years, I'm wondering if there's anything up with poll(2). (If it's a direct bug with rsh, well, that's fixed a different way in -current).. ... 241 if ((pfd[0].revents (POLLERR|POLLHUP|POLLNVAL)) || 242 (pfd[1].revents (POLLERR|POLLHUP|POLLNVAL))) 243 err(1, poll); It's reporting that the second fd, the stderr fd, has been closed by the other side (POLLHUP). Does ipcad implement the expected ordering in the rsh protocol? Philip Guenther
Re: rsh vs net/ipcad - problems on 5.5
On 2014/05/20 12:36, Philip Guenther wrote: On Tue, May 20, 2014 at 8:29 AM, Stuart Henderson st...@openbsd.org wrote: On 2014/05/20 16:41, viq wrote: I encountered a strange problem when trying to communicate with net/ipcad: rsh localhost stats rsh: poll: Undefined error: 0 ... Note that ipcad listens on port 514 and provides *its own* cisco-ish rshell interface that you connect to, this isn't about openbsd rshd. The error is coming from /usr/src/usr.bin/rsh/rsh.c:243 and since nothing changed here in many years, I'm wondering if there's anything up with poll(2). (If it's a direct bug with rsh, well, that's fixed a different way in -current).. ... 241 if ((pfd[0].revents (POLLERR|POLLHUP|POLLNVAL)) || 242 (pfd[1].revents (POLLERR|POLLHUP|POLLNVAL))) 243 err(1, poll); It's reporting that the second fd, the stderr fd, has been closed by the other side (POLLHUP). Does ipcad implement the expected ordering in the rsh protocol? Philip Guenther Thanks for the cluebat / lesson in rsh :) Seems it's actually racey, sometimes closing the stderr first, sometimes closing port 514 first. So no it doesn't ... And rshd works fine, reinforcing this i.e. seems like an ipcad bug. Still it seems odd that it stopped working in 5.5 (though not enough for me to spend longer looking!). rsh ipcad 54 55 ok 55 54 ok 55 55 fail Anyway Viq, since rsh has gone away in -current, I suggest looking for an alternative; there are various things which might be suitable depending on what you're actually using it for .. Now to remove my test rshd configs before I forget :-)
