search for: ssh_msg_ignore

...echanism. */ channel_prepare_select(readsetp, writesetp, maxfdp, rekeying); @@ -356,13 +359,29 @@ /* * Wait for something to happen. This will suspend the process until * some selected descriptor can be read, written, or has some other - * event pending. Note: if you want to implement SSH_MSG_IGNORE - * messages to fool traffic analysis, this might be the place to do - * it: just have a random timeout for the select, and send a random - * SSH_MSG_IGNORE packet when the timeout expires. + * event pending. + * Set a random timeout for the select, and send a random SSH_MSG_IGNORE + * packet...

Heya, Most of the windows ssh clients (putty, securecrt) have anti-idle features. They offer either a null packet or protocol no-op or user defined string to be sent over every x seconds. Is this possible or planned with the OpenSSH client? Our draconian firewall admins have started timing out ssh sessions. Yes I'm aware I could hack up a port forwarding dumb traffic process, but was

...ritesetp, int *maxfdp) { + struct timeval tv = {0}; + tv.tv_sec = options.noop_msg_frequency; + /* Send a noop message at this frequency as a keepalive. */ + /* Add any selections by the channel mechanism. */ channel_prepare_select(readsetp, writesetp, maxfdp); @@ -403,7 +407,8 @@ * SSH_MSG_IGNORE packet when the timeout expires. */ - if (select((*maxfdp)+1, *readsetp, *writesetp, NULL, NULL) < 0) { + switch (select((*maxfdp)+1, *readsetp, *writesetp, NULL, ((tv.tv_sec)?(&tv):NULL))) { + case -1: { char buf[100]; /* @@ -420,7 +425,21 @@ snprintf(buf, sizeof...

http://bugzilla.mindrot.org/show_bug.cgi?id=1307 Summary: client disconnects if ServerAlive enabled but not implemented Product: Portable OpenSSH Version: 4.3p2 Platform: Other OS/Version: Linux Status: NEW Severity: normal Priority: P2 Component: ssh AssignedTo: bitbucket at

...itialize select masks. */ FD_ZERO(readset); @@ -436,15 +438,32 @@ max_fd = channel_max_fd(); /* - * Wait for something to happen. This will suspend the process until - * some selected descriptor can be read, written, or has some other - * event pending. Note: if you want to implement SSH_MSG_IGNORE - * messages to fool traffic analysis, this might be the place to do - * it: just have a random timeout for the select, and send a random - * SSH_MSG_IGNORE packet when the timeout expires. + * Wait for something to happen. This will suspend the process + * until some selected descriptor can...

Hi, protocolkeepalives sends ssh_msg_ignore, which the ssh2 server handles incorrectly (i.e. it produces some output to syslog, instead of ignoring the packet): Jul 9 11:58:07 ren sshd[16580]: error: Hm, dispatch protocol error: type 32 plen 4 This patch implements a highly advanced function to ignore these packets ;) Matthew -----------...

...the fact that the HTTP proxy server closes the connection after 60 seconds of inactivity. Attached below is a patch that implements a new configuration option called "Idle" that lets you specify the maximum idle time of a connection in seconds. When this limit is reached, a dummy packet (SSH_MSG_IGNORE) is sent, to fake activity, and to prevent the timeout. This option might be usefull for others, so I'm posting it here. -- Dick Streefland //// De Bilt dick.streefland at xs4all.nl (@ @) The Netherlands ------------------------------oOO--(_)--OO...

...is today. Still, I feel bad about letting the patch sit only in Debian forever, so I feel obliged to send this up here! The attached patch adds partial support for ServerAliveInterval in SSH1. ServerAliveCountMax doesn't work (and is documented as such) because we don't get a response to SSH_MSG_IGNORE, but I think this is as good as it's possible to get. -- Configure bugmail: https://bugzilla.mindrot.org/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are watching the assignee of the bug.

Dear Developers, I've released a patch against openssh-2.5.2p2. The patch adds heartbeat (keepalive) function to ssh(1), and watchdog timeout function to sshd(8). The watchdog timeout is intended to terminate user's processes as soon as possible after the link has been lost. http://www.ecip.tohoku.ac.jp/~hgot/sources/openssh-watchdog.html The combination of the heartbeat and the

Hello, Hideaki Goto has written a patch for OpenSSH that adds heartbeat and watchdog functions to OpenSSH: http://www.sc.isc.tohoku.ac.jp/~hgot/sources/openssh-watchdog.html The heartbeat function sends an SSH_MSG_IGNORE packet every <n> seconds to the server, and the watchdog function checks incoming packets only to see if the connection has been interrupted. Where I work, all Internet connections go through an HTTPS proxy. Without this patch, I wouldn't be able to stay connected to any outside servers...

[ After looking over the openssh.com website, this seems to be the list to use, including for OpenBSD users? I've subscribed. ] I'm using OpenSSH_2.5.0 as currently found in OpenBSD's OPENBSD_2_8 CVS branch. I'm now finding a strange error when I try to su, _within_ the connection. The client side is _not_ OpenSSH. Every single time that I type "su -", and local

...if ((session_status == SessionClose) + && !channel_still_open()) { + if (!packet_have_data_to_write()) { + return; + } + } else { + FD_SET(connection_in, *readsetp); + } } /* Select server connection if have data to write to the server. */ @@ -362,7 +374,16 @@ * SSH_MSG_IGNORE packet when the timeout expires. */ - if (select((*maxfdp)+1, *readsetp, *writesetp, NULL, NULL) < 0) { + if(session_status == SessionWait && options.sleep > 0) { + timer.tv_sec=options.sleep; + timer.tv_usec=0; + timerp=&timer; + } else { + timerp=NULL; + } + + rc=selec...

...if (session_closed && !channel_still_open() && + if (session_status == SessionClose && !channel_still_open() && !packet_have_data_to_write()) { /* clear mask since we did not call select() */ memset(*readsetp, 0, *nallocp); @@ -367,7 +373,16 @@ * SSH_MSG_IGNORE packet when the timeout expires. */ - if (select((*maxfdp)+1, *readsetp, *writesetp, NULL, NULL) < 0) { + if(session_status == SessionWait && options.sleep > 0) { + timer.tv_sec=options.sleep > 0 ? options.sleep : 0; + timer.tv_usec=0; + timerp=&timer; + } else { + tim...

...d && !channel_still_open()) { + if ((session_status == SessionClose) + && !channel_still_open()) { if (!packet_have_data_to_write()) return; } else { - FD_SET(connection_in, *readsetp); + FD_SET(connection_in, *readsetp); } } @@ -364,7 +371,17 @@ * SSH_MSG_IGNORE packet when the timeout expires. */ - if (select((*maxfdp)+1, *readsetp, *writesetp, NULL, NULL) < 0) { + if((session_status == SessionWait && options.sleep > 0) || + (no_tty_flag && options.sleep == -1)) { + timer.tv_sec=options.sleep > 0 ? options.sleep : 0; +...

In the changelog, there is an entry: 20001129 - (djm) Back out all the serverloop.c hacks. sshd will now hang again if there are background children with open fds. Does this mean that this is regarded as expected (and correct) behavior, that should not change in the future, or does it mean that this behavior is a known problem that someone will eventually fix? --Adam -- Adam McKenna

...- if (session_closed && !channel_still_open() && + if (session_status == SessionClose && !channel_still_open() && !packet_have_data_to_write()) { /* clear mask since we did not call select() */ memset(*readsetp, 0, *maxfdp); @@ -367,7 +373,17 @@ * SSH_MSG_IGNORE packet when the timeout expires. */ - if (select((*maxfdp)+1, *readsetp, *writesetp, NULL, NULL) < 0) { + if((session_status == SessionWait && options.sleep > 0) || + (no_tty_flag && options.sleep == -1)) { + timer.tv_sec=options.sleep > 0 ? options.sleep : 0; +...

Dear all, For my thesis, I've been working on automatic inference of state machines for SSH servers. I ran into a couple of particularities regarding OpenSSH's inferred state machine, and was hoping some of you might be interested. Maybe you can even shed some light on it. Setup: I'm using LearnLib's (Java) version of the L* learning algorithm [1] to come up with sequences of

I'm reading this fine article on O'Reilly: http://linux.oreillynet.com/lpt/a//linux/2001/11/08/ssh_keystroke.html <quote> The paper concludes that the keystroke timing data observable from today's SSH implementations reveals a dangerously significant amount of information about user terminal sessions--enough to locate typed passwords in the session data stream and reduce the

...FD_SET(connection_in, *readsetp); - } + FD_SET(connection_in, *readsetp); } /* Select server connection if have data to write to the server. */ @@ -363,9 +393,34 @@ * it: just have a random timeout for the select, and send a random * SSH_MSG_IGNORE packet when the timeout expires. */ + + /* + * Begin SD Mod: + * Enforce wait send packets every 50 ms. To do this add timer to + * select loop. Buffer input as it comes and force the timer to decrement + * if select call does not do so. +...

Hello, In response to the timing analysis attacks presented by Dawn Song et. al. in her paper http://paris.cs.berkeley.edu/~dawnsong/ssh-timing.html we at Silicon Defense developed a patch for openssh to avoid such measures. Timing Analysis Evasion changes were developed by C. Jason Coit and Roel Jonkman of Silicon Defense. These changes cause SSH to send packets unless request not to,