- djm@cvs.openbsd.org 2008/05/09 14:18:44
[clientloop.c clientloop.h ssh.c mux.c]
tidy up session multiplexing code, moving it into its own file and
making the function names more consistent - making ssh.c and
clientloop.c a fair bit more readable.
ok markus@
diff --git a/ssh.c b/ssh.c
index cfefade..c944d0a 100644
--- a/ssh.c
+++ b/ssh.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh.c,v 1.311 2008/05/08 13:06:11 djm Exp $ */
+/* $OpenBSD: ssh.c,v 1.312 2008/05/09 14:18:44 djm Exp $ */
/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -49,7 +49,6 @@
#include <sys/resource.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
-#include <sys/un.h>
#include <ctype.h>
#include <errno.h>
@@ -99,7 +98,6 @@
#include "sshpty.h"
#include "match.h"
#include "msg.h"
-#include "monitor_fdpass.h"
#include "uidswap.h"
#include "version.h"
@@ -171,15 +169,9 @@
/* pid of proxycommand child process */
pid_t proxy_command_pid = 0;
-/* fd to control socket */
-int control_fd = -1;
-
-/* Multiplexing control command */
-static u_int mux_command = 0;
-
-/* Only used in control client mode */
-volatile sig_atomic_t control_client_terminate = 0;
-u_int control_server_pid = 0;
+/* mux.c */
+extern int muxserver_sock;
+extern u_int muxclient_command;
/* Prints a help message to the user. This function never returns. */
@@ -200,7 +192,10 @@
static int ssh_session(void);
static int ssh_session2(void);
static void load_public_identity_files(void);
-static void control_client(const char *path);
+
+/* from muxclient.c */
+void muxclient(const char *);
+void muxserver_listen(void);
/*
* Main program for the ssh client.
@@ -310,9 +305,9 @@
break;
case 'O':
if (strcmp(optarg, "check") == 0)
- mux_command = SSHMUX_COMMAND_ALIVE_CHECK;
+ muxclient_command = SSHMUX_COMMAND_ALIVE_CHECK;
else if (strcmp(optarg, "exit") == 0)
- mux_command = SSHMUX_COMMAND_TERMINATE;
+ muxclient_command = SSHMUX_COMMAND_TERMINATE;
else
fatal("Invalid multiplex command.");
break;
@@ -683,10 +678,10 @@
"r", options.user, "l", thishost, (char *)NULL);
xfree(cp);
}
- if (mux_command != 0 && options.control_path == NULL)
+ if (muxclient_command != 0 && options.control_path == NULL)
fatal("No ControlPath specified for \"-O\" command");
if (options.control_path != NULL)
- control_client(options.control_path);
+ muxclient(options.control_path);
timeout_ms = options.connection_timeout * 1000;
@@ -809,7 +804,7 @@
exit_status = compat20 ? ssh_session2() : ssh_session();
packet_close();
- if (options.control_path != NULL && control_fd != -1)
+ if (options.control_path != NULL && muxserver_sock != -1)
unlink(options.control_path);
/*
@@ -1064,48 +1059,6 @@
}
}
-static void
-ssh_control_listener(void)
-{
- struct sockaddr_un addr;
- mode_t old_umask;
- int addr_len;
-
- if (options.control_path == NULL ||
- options.control_master == SSHCTL_MASTER_NO)
- return;
-
- debug("setting up multiplex master socket");
-
- memset(&addr, '\0', sizeof(addr));
- addr.sun_family = AF_UNIX;
- addr_len = offsetof(struct sockaddr_un, sun_path) +
- strlen(options.control_path) + 1;
-
- if (strlcpy(addr.sun_path, options.control_path,
- sizeof(addr.sun_path)) >= sizeof(addr.sun_path))
- fatal("ControlPath too long");
-
- if ((control_fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0)
- fatal("%s socket(): %s", __func__, strerror(errno));
-
- old_umask = umask(0177);
- if (bind(control_fd, (struct sockaddr *)&addr, addr_len) == -1) {
- control_fd = -1;
- if (errno == EINVAL || errno == EADDRINUSE)
- fatal("ControlSocket %s already exists",
- options.control_path);
- else
- fatal("%s bind(): %s", __func__, strerror(errno));
- }
- umask(old_umask);
-
- if (listen(control_fd, 64) == -1)
- fatal("%s listen(): %s", __func__, strerror(errno));
-
- set_nonblock(control_fd);
-}
-
/* request pty/x11/agent/tcpfwd/shell for channel */
static void
ssh_session2_setup(int id, void *arg)
@@ -1204,7 +1157,7 @@
ssh_local_cmd(options.local_command);
/* Start listening for multiplex clients */
- ssh_control_listener();
+ muxserver_listen();
/* If requested, let ssh continue in the background. */
if (fork_after_authentication_flag)
@@ -1272,237 +1225,3 @@
bzero(pwdir, strlen(pwdir));
xfree(pwdir);
}
-
-static void
-control_client_sighandler(int signo)
-{
- control_client_terminate = signo;
-}
-
-static void
-control_client_sigrelay(int signo)
-{
- int save_errno = errno;
-
- if (control_server_pid > 1)
- kill(control_server_pid, signo);
-
- errno = save_errno;
-}
-
-static int
-env_permitted(char *env)
-{
- int i, ret;
- char name[1024], *cp;
-
- if ((cp = strchr(env, '=')) == NULL || cp == env)
- return (0);
- ret = snprintf(name, sizeof(name), "%.*s", (int)(cp - env), env);
- if (ret <= 0 || (size_t)ret >= sizeof(name))
- fatal("env_permitted: name '%.100s...' too long", env);
-
- for (i = 0; i < options.num_send_env; i++)
- if (match_pattern(name, options.send_env[i]))
- return (1);
-
- return (0);
-}
-
-static void
-control_client(const char *path)
-{
- struct sockaddr_un addr;
- int i, r, fd, sock, exitval[2], num_env, addr_len;
- Buffer m;
- char *term;
- extern char **environ;
- u_int flags;
-
- if (mux_command == 0)
- mux_command = SSHMUX_COMMAND_OPEN;
-
- switch (options.control_master) {
- case SSHCTL_MASTER_AUTO:
- case SSHCTL_MASTER_AUTO_ASK:
- debug("auto-mux: Trying existing master");
- /* FALLTHROUGH */
- case SSHCTL_MASTER_NO:
- break;
- default:
- return;
- }
-
- memset(&addr, '\0', sizeof(addr));
- addr.sun_family = AF_UNIX;
- addr_len = offsetof(struct sockaddr_un, sun_path) +
- strlen(path) + 1;
-
- if (strlcpy(addr.sun_path, path,
- sizeof(addr.sun_path)) >= sizeof(addr.sun_path))
- fatal("ControlPath too long");
-
- if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) < 0)
- fatal("%s socket(): %s", __func__, strerror(errno));
-
- if (connect(sock, (struct sockaddr *)&addr, addr_len) == -1) {
- if (mux_command != SSHMUX_COMMAND_OPEN) {
- fatal("Control socket connect(%.100s): %s", path,
- strerror(errno));
- }
- if (errno == ENOENT)
- debug("Control socket \"%.100s\" does not exist", path);
- else {
- error("Control socket connect(%.100s): %s", path,
- strerror(errno));
- }
- close(sock);
- return;
- }
-
- if (stdin_null_flag) {
- if ((fd = open(_PATH_DEVNULL, O_RDONLY)) == -1)
- fatal("open(/dev/null): %s", strerror(errno));
- if (dup2(fd, STDIN_FILENO) == -1)
- fatal("dup2: %s", strerror(errno));
- if (fd > STDERR_FILENO)
- close(fd);
- }
-
- term = getenv("TERM");
-
- flags = 0;
- if (tty_flag)
- flags |= SSHMUX_FLAG_TTY;
- if (subsystem_flag)
- flags |= SSHMUX_FLAG_SUBSYS;
- if (options.forward_x11)
- flags |= SSHMUX_FLAG_X11_FWD;
- if (options.forward_agent)
- flags |= SSHMUX_FLAG_AGENT_FWD;
-
- signal(SIGPIPE, SIG_IGN);
-
- buffer_init(&m);
-
- /* Send our command to server */
- buffer_put_int(&m, mux_command);
- buffer_put_int(&m, flags);
- if (ssh_msg_send(sock, SSHMUX_VER, &m) == -1)
- fatal("%s: msg_send", __func__);
- buffer_clear(&m);
-
- /* Get authorisation status and PID of controlee */
- if (ssh_msg_recv(sock, &m) == -1)
- fatal("%s: msg_recv", __func__);
- if (buffer_get_char(&m) != SSHMUX_VER)
- fatal("%s: wrong version", __func__);
- if (buffer_get_int(&m) != 1)
- fatal("Connection to master denied");
- control_server_pid = buffer_get_int(&m);
-
- buffer_clear(&m);
-
- switch (mux_command) {
- case SSHMUX_COMMAND_ALIVE_CHECK:
- fprintf(stderr, "Master running (pid=%d)\r\n",
- control_server_pid);
- exit(0);
- case SSHMUX_COMMAND_TERMINATE:
- fprintf(stderr, "Exit request sent.\r\n");
- exit(0);
- case SSHMUX_COMMAND_OPEN:
- /* continue below */
- break;
- default:
- fatal("silly mux_command %d", mux_command);
- }
-
- /* SSHMUX_COMMAND_OPEN */
- buffer_put_cstring(&m, term ? term : "");
- buffer_append(&command, "\0", 1);
- buffer_put_cstring(&m, buffer_ptr(&command));
-
- if (options.num_send_env == 0 || environ == NULL) {
- buffer_put_int(&m, 0);
- } else {
- /* Pass environment */
- num_env = 0;
- for (i = 0; environ[i] != NULL; i++)
- if (env_permitted(environ[i]))
- num_env++; /* Count */
-
- buffer_put_int(&m, num_env);
-
- for (i = 0; environ[i] != NULL && num_env >= 0; i++)
- if (env_permitted(environ[i])) {
- num_env--;
- buffer_put_cstring(&m, environ[i]);
- }
- }
-
- if (ssh_msg_send(sock, SSHMUX_VER, &m) == -1)
- fatal("%s: msg_send", __func__);
-
- if (mm_send_fd(sock, STDIN_FILENO) == -1 ||
- mm_send_fd(sock, STDOUT_FILENO) == -1 ||
- mm_send_fd(sock, STDERR_FILENO) == -1)
- fatal("%s: send fds failed", __func__);
-
- /* Wait for reply, so master has a chance to gather ttymodes */
- buffer_clear(&m);
- if (ssh_msg_recv(sock, &m) == -1)
- fatal("%s: msg_recv", __func__);
- if (buffer_get_char(&m) != SSHMUX_VER)
- fatal("%s: wrong version", __func__);
- buffer_free(&m);
-
- signal(SIGHUP, control_client_sighandler);
- signal(SIGINT, control_client_sighandler);
- signal(SIGTERM, control_client_sighandler);
- signal(SIGWINCH, control_client_sigrelay);
-
- if (tty_flag)
- enter_raw_mode();
-
- /*
- * Stick around until the controlee closes the client_fd.
- * Before it does, it is expected to write this process' exit
- * value (one int). This process must read the value and wait for
- * the closure of the client_fd; if this one closes early, the
- * multiplex master will terminate early too (possibly losing data).
- */
- exitval[0] = 0;
- for (i = 0; !control_client_terminate && i < (int)sizeof(exitval);) {
- r = read(sock, (char *)exitval + i, sizeof(exitval) - i);
- if (r == 0) {
- debug2("Received EOF from master");
- break;
- }
- if (r == -1) {
- if (errno == EINTR)
- continue;
- fatal("%s: read %s", __func__, strerror(errno));
- }
- i += r;
- }
-
- close(sock);
- leave_raw_mode();
- if (i > (int)sizeof(int))
- fatal("%s: master returned too much data (%d > %lu)",
- __func__, i, sizeof(int));
- if (control_client_terminate) {
- debug2("Exiting on signal %d", control_client_terminate);
- exitval[0] = 255;
- } else if (i < (int)sizeof(int)) {
- debug2("Control master terminated unexpectedly");
- exitval[0] = 255;
- } else
- debug2("Received exit status from master %d", exitval[0]);
-
- if (tty_flag && options.log_level != SYSLOG_LEVEL_QUIET)
- fprintf(stderr, "Shared connection to %s closed.\r\n", host);
-
- exit(exitval[0]);
-}