From c99deca40eecb33ffe93e2290337833afb9493aa Mon Sep 17 00:00:00 2001 From: ben Date: Thu, 2 Aug 2012 22:18:18 +0000 Subject: [PATCH] Reduce the number of round-trips involved in opening an SSH-2 session by sending most of the initial SSH_MSG_CHANNEL_REQUEST messages before waiting for any replies. The initial version of this code was a clever thing with a two-pass loop, but that got hairy so I went for the simpler approach of separating the request and reply code and having flags to keep track of which requests have been sent. git-svn-id: svn://svn.tartarus.org/sgt/putty@9599 cda61777-01e9-0310-a592-d414129be87e --- ssh.c | 185 +++++++++++++++++++++++++++++++++++++----------------------------- 1 file changed, 105 insertions(+), 80 deletions(-) diff --git a/ssh.c b/ssh.c index 351003fd..f39894ae 100644 --- a/ssh.c +++ b/ssh.c @@ -7512,6 +7512,9 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int siglen, retlen, len; char *q, *agentreq, *ret; int try_send; + int requested_x11; + int requested_agent; + int requested_tty; int num_env, env_left, env_ok; struct Packet *pktout; Filename *keyfile; @@ -8999,6 +9002,17 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, } /* + * Enable port forwardings. + */ + ssh_setup_portfwd(ssh, ssh->conf); + + /* + * Send the CHANNEL_REQUESTS for the main channel. We send them all + * and then start looking for responses, so it's important that the + * sending and receiving code below it is kept in sync. + */ + + /* * Potentially enable X11 forwarding. */ if (ssh->mainchan && !ssh->ncmode && conf_get_int(ssh->conf, CONF_x11_forward) && @@ -9023,26 +9037,9 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, end_log_omission(ssh, s->pktout); ssh2_pkt_adduint32(s->pktout, ssh->x11disp->screennum); ssh2_pkt_send(ssh, s->pktout); - - crWaitUntilV(pktin); - - if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) { - if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) { - bombout(("Unexpected response to X11 forwarding request:" - " packet type %d", pktin->type)); - crStopV; - } - logevent("X11 forwarding refused"); - } else { - logevent("X11 forwarding enabled"); - ssh->X11_fwd_enabled = TRUE; - } - } - - /* - * Enable port forwardings. - */ - ssh_setup_portfwd(ssh, ssh->conf); + s->requested_x11 = TRUE; + } else + s->requested_x11 = FALSE; /* * Potentially enable agent forwarding. @@ -9054,21 +9051,9 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, ssh2_pkt_addstring(s->pktout, "auth-agent-req@openssh.com"); ssh2_pkt_addbool(s->pktout, 1); /* want reply */ ssh2_pkt_send(ssh, s->pktout); - - crWaitUntilV(pktin); - - if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) { - if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) { - bombout(("Unexpected response to agent forwarding request:" - " packet type %d", pktin->type)); - crStopV; - } - logevent("Agent forwarding refused"); - } else { - logevent("Agent forwarding enabled"); - ssh->agentfwd_enabled = TRUE; - } - } + s->requested_agent = TRUE; + } else + s->requested_agent = FALSE; /* * Now allocate a pty for the session. @@ -9097,25 +9082,9 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, ssh2_pkt_addstring_data(s->pktout, "\0", 1); /* TTY_OP_END */ ssh2_pkt_send(ssh, s->pktout); ssh->state = SSH_STATE_INTERMED; - - crWaitUntilV(pktin); - - if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) { - if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) { - bombout(("Unexpected response to pty request:" - " packet type %d", pktin->type)); - crStopV; - } - c_write_str(ssh, "Server refused to allocate pty\r\n"); - ssh->editing = ssh->echoing = 1; - } else { - logeventf(ssh, "Allocated pty (ospeed %dbps, ispeed %dbps)", - ssh->ospeed, ssh->ispeed); - ssh->got_pty = TRUE; - } - } else { - ssh->editing = ssh->echoing = 1; - } + s->requested_tty = TRUE; + } else + s->requested_tty = FALSE; /* * Send environment variables. @@ -9123,11 +9092,10 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, * Simplest thing here is to send all the requests at once, and * then wait for a whole bunch of successes or failures. */ + s->num_env = 0; if (ssh->mainchan && !ssh->ncmode) { char *key, *val; - s->num_env = 0; - for (val = conf_get_str_strs(ssh->conf, CONF_environmt, NULL, &key); val != NULL; val = conf_get_str_strs(ssh->conf, CONF_environmt, key, &key)) { @@ -9141,39 +9109,96 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, s->num_env++; } - - if (s->num_env) { + if (s->num_env) logeventf(ssh, "Sent %d environment variables", s->num_env); + } - s->env_ok = 0; - s->env_left = s->num_env; + /* + * All CHANNEL_REQUESTs sent. Now collect up the replies. These + * must be in precisely the same order as the requests. + */ - while (s->env_left > 0) { - crWaitUntilV(pktin); + if (s->requested_x11) { + crWaitUntilV(pktin); - if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) { - if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) { - bombout(("Unexpected response to environment request:" - " packet type %d", pktin->type)); - crStopV; - } - } else { - s->env_ok++; - } + if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) { + if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) { + bombout(("Unexpected response to X11 forwarding request:" + " packet type %d", pktin->type)); + crStopV; + } + logevent("X11 forwarding refused"); + } else { + logevent("X11 forwarding enabled"); + ssh->X11_fwd_enabled = TRUE; + } + } + + if (s->requested_agent) { + crWaitUntilV(pktin); + + if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) { + if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) { + bombout(("Unexpected response to agent forwarding request:" + " packet type %d", pktin->type)); + crStopV; + } + logevent("Agent forwarding refused"); + } else { + logevent("Agent forwarding enabled"); + ssh->agentfwd_enabled = TRUE; + } + } + + if (s->requested_tty) { + crWaitUntilV(pktin); - s->env_left--; + if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) { + if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) { + bombout(("Unexpected response to pty request:" + " packet type %d", pktin->type)); + crStopV; } + c_write_str(ssh, "Server refused to allocate pty\r\n"); + ssh->editing = ssh->echoing = 1; + } else { + logeventf(ssh, "Allocated pty (ospeed %dbps, ispeed %dbps)", + ssh->ospeed, ssh->ispeed); + ssh->got_pty = TRUE; + } + } else { + ssh->editing = ssh->echoing = 1; + } - if (s->env_ok == s->num_env) { - logevent("All environment variables successfully set"); - } else if (s->env_ok == 0) { - logevent("All environment variables refused"); - c_write_str(ssh, "Server refused to set environment variables\r\n"); + if (s->num_env) { + s->env_ok = 0; + s->env_left = s->num_env; + + while (s->env_left > 0) { + crWaitUntilV(pktin); + + if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) { + if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) { + bombout(("Unexpected response to environment request:" + " packet type %d", pktin->type)); + crStopV; + } } else { - logeventf(ssh, "%d environment variables refused", - s->num_env - s->env_ok); - c_write_str(ssh, "Server refused to set all environment variables\r\n"); + s->env_ok++; } + + s->env_left--; + } + + if (s->env_ok == s->num_env) { + logevent("All environment variables successfully set"); + } else if (s->env_ok == 0) { + logevent("All environment variables refused"); + c_write_str(ssh, "Server refused to set environment variables\r\n"); + } else { + logeventf(ssh, "%d environment variables refused", + s->num_env - s->env_ok); + c_write_str(ssh, "Server refused to set all environment variables\r\n"); } } -- 2.11.0