Annotation of src/usr.bin/ssh/session.c, Revision 1.23
1.1 markus 1: /*
2: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
3: * All rights reserved
4: */
1.2 markus 5: /*
6: * SSH2 support by Markus Friedl.
7: * Copyright (c) 2000 Markus Friedl. All rights reserved.
8: */
1.1 markus 9:
10: #include "includes.h"
1.23 ! deraadt 11: RCSID("$OpenBSD: session.c,v 1.22 2000/07/05 20:18:07 deraadt Exp $");
1.1 markus 12:
13: #include "xmalloc.h"
14: #include "ssh.h"
15: #include "pty.h"
16: #include "packet.h"
17: #include "buffer.h"
18: #include "cipher.h"
19: #include "mpaux.h"
20: #include "servconf.h"
21: #include "uidswap.h"
22: #include "compat.h"
23: #include "channels.h"
24: #include "nchan.h"
25:
1.2 markus 26: #include "bufaux.h"
27: #include "ssh2.h"
28: #include "auth.h"
1.19 markus 29: #include "auth-options.h"
1.2 markus 30:
1.1 markus 31: /* types */
32:
33: #define TTYSZ 64
34: typedef struct Session Session;
35: struct Session {
36: int used;
37: int self;
1.7 markus 38: int extended;
1.1 markus 39: struct passwd *pw;
40: pid_t pid;
41: /* tty */
42: char *term;
43: int ptyfd, ttyfd, ptymaster;
44: int row, col, xpixel, ypixel;
45: char tty[TTYSZ];
46: /* X11 */
47: char *display;
48: int screen;
49: char *auth_proto;
50: char *auth_data;
1.7 markus 51: int single_connection;
1.1 markus 52: /* proto 2 */
53: int chanid;
54: };
55:
56: /* func */
57:
58: Session *session_new(void);
59: void session_set_fds(Session *s, int fdin, int fdout, int fderr);
60: void session_pty_cleanup(Session *s);
1.9 markus 61: void session_proctitle(Session *s);
1.1 markus 62: void do_exec_pty(Session *s, const char *command, struct passwd * pw);
63: void do_exec_no_pty(Session *s, const char *command, struct passwd * pw);
64:
65: void
66: do_child(const char *command, struct passwd * pw, const char *term,
67: const char *display, const char *auth_proto,
68: const char *auth_data, const char *ttyname);
69:
70: /* import */
71: extern ServerOptions options;
72: extern char *__progname;
73: extern int log_stderr;
74: extern int debug_flag;
75:
1.21 markus 76: extern int startup_pipe;
77:
1.1 markus 78: /* Local Xauthority file. */
79: static char *xauthfile;
80:
81: /* data */
82: #define MAX_SESSIONS 10
83: Session sessions[MAX_SESSIONS];
84:
85: /*
86: * Remove local Xauthority file.
87: */
88: void
89: xauthfile_cleanup_proc(void *ignore)
90: {
91: debug("xauthfile_cleanup_proc called");
92:
93: if (xauthfile != NULL) {
94: char *p;
95: unlink(xauthfile);
96: p = strrchr(xauthfile, '/');
97: if (p != NULL) {
98: *p = '\0';
99: rmdir(xauthfile);
100: }
101: xfree(xauthfile);
102: xauthfile = NULL;
103: }
104: }
105:
106: /*
107: * Function to perform cleanup if we get aborted abnormally (e.g., due to a
108: * dropped connection).
109: */
1.4 markus 110: void
1.1 markus 111: pty_cleanup_proc(void *session)
112: {
113: Session *s=session;
114: if (s == NULL)
115: fatal("pty_cleanup_proc: no session");
116: debug("pty_cleanup_proc: %s", s->tty);
117:
118: if (s->pid != 0) {
119: /* Record that the user has logged out. */
120: record_logout(s->pid, s->tty);
121: }
122:
123: /* Release the pseudo-tty. */
124: pty_release(s->tty);
125: }
126:
127: /*
128: * Prepares for an interactive session. This is called after the user has
129: * been successfully authenticated. During this message exchange, pseudo
130: * terminals are allocated, X11, TCP/IP, and authentication agent forwardings
131: * are requested, etc.
132: */
1.4 markus 133: void
1.1 markus 134: do_authenticated(struct passwd * pw)
135: {
136: Session *s;
137: int type;
138: int compression_level = 0, enable_compression_after_reply = 0;
139: int have_pty = 0;
140: char *command;
141: int n_bytes;
142: int plen;
143: unsigned int proto_len, data_len, dlen;
144:
145: /*
146: * Cancel the alarm we set to limit the time taken for
147: * authentication.
148: */
149: alarm(0);
1.23 ! deraadt 150: if (startup_pipe != -1) {
! 151: close(startup_pipe);
! 152: startup_pipe = -1;
! 153: }
1.1 markus 154:
155: /*
156: * Inform the channel mechanism that we are the server side and that
157: * the client may request to connect to any port at all. (The user
158: * could do it anyway, and we wouldn\'t know what is permitted except
159: * by the client telling us, so we can equally well trust the client
160: * not to request anything bogus.)
161: */
162: if (!no_port_forwarding_flag)
163: channel_permit_all_opens();
164:
165: s = session_new();
1.7 markus 166: s->pw = pw;
1.1 markus 167:
168: /*
169: * We stay in this loop until the client requests to execute a shell
170: * or a command.
171: */
172: for (;;) {
173: int success = 0;
174:
175: /* Get a packet from the client. */
176: type = packet_read(&plen);
177:
178: /* Process the packet. */
179: switch (type) {
180: case SSH_CMSG_REQUEST_COMPRESSION:
181: packet_integrity_check(plen, 4, type);
182: compression_level = packet_get_int();
183: if (compression_level < 1 || compression_level > 9) {
184: packet_send_debug("Received illegal compression level %d.",
185: compression_level);
186: break;
187: }
188: /* Enable compression after we have responded with SUCCESS. */
189: enable_compression_after_reply = 1;
190: success = 1;
191: break;
192:
193: case SSH_CMSG_REQUEST_PTY:
194: if (no_pty_flag) {
195: debug("Allocating a pty not permitted for this authentication.");
196: break;
197: }
198: if (have_pty)
199: packet_disconnect("Protocol error: you already have a pty.");
200:
201: debug("Allocating pty.");
202:
203: /* Allocate a pty and open it. */
204: if (!pty_allocate(&s->ptyfd, &s->ttyfd, s->tty,
205: sizeof(s->tty))) {
206: error("Failed to allocate pty.");
207: break;
208: }
209: fatal_add_cleanup(pty_cleanup_proc, (void *)s);
210: pty_setowner(pw, s->tty);
211:
212: /* Get TERM from the packet. Note that the value may be of arbitrary length. */
213: s->term = packet_get_string(&dlen);
214: packet_integrity_check(dlen, strlen(s->term), type);
215: /* packet_integrity_check(plen, 4 + dlen + 4*4 + n_bytes, type); */
216: /* Remaining bytes */
217: n_bytes = plen - (4 + dlen + 4 * 4);
218:
219: if (strcmp(s->term, "") == 0) {
220: xfree(s->term);
221: s->term = NULL;
222: }
223: /* Get window size from the packet. */
224: s->row = packet_get_int();
225: s->col = packet_get_int();
226: s->xpixel = packet_get_int();
227: s->ypixel = packet_get_int();
228: pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
229:
230: /* Get tty modes from the packet. */
231: tty_parse_modes(s->ttyfd, &n_bytes);
232: packet_integrity_check(plen, 4 + dlen + 4 * 4 + n_bytes, type);
1.10 markus 233:
234: session_proctitle(s);
1.1 markus 235:
236: /* Indicate that we now have a pty. */
237: success = 1;
238: have_pty = 1;
239: break;
240:
241: case SSH_CMSG_X11_REQUEST_FORWARDING:
242: if (!options.x11_forwarding) {
243: packet_send_debug("X11 forwarding disabled in server configuration file.");
244: break;
245: }
1.16 markus 246: if (!options.xauth_location) {
247: packet_send_debug("No xauth program; cannot forward with spoofing.");
248: break;
249: }
1.1 markus 250: if (no_x11_forwarding_flag) {
251: packet_send_debug("X11 forwarding not permitted for this authentication.");
252: break;
253: }
254: debug("Received request for X11 forwarding with auth spoofing.");
255: if (s->display != NULL)
256: packet_disconnect("Protocol error: X11 display already set.");
257:
258: s->auth_proto = packet_get_string(&proto_len);
259: s->auth_data = packet_get_string(&data_len);
260: packet_integrity_check(plen, 4 + proto_len + 4 + data_len + 4, type);
261:
262: if (packet_get_protocol_flags() & SSH_PROTOFLAG_SCREEN_NUMBER)
263: s->screen = packet_get_int();
264: else
265: s->screen = 0;
266: s->display = x11_create_display_inet(s->screen, options.x11_display_offset);
267:
268: if (s->display == NULL)
269: break;
270:
271: /* Setup to always have a local .Xauthority. */
272: xauthfile = xmalloc(MAXPATHLEN);
273: strlcpy(xauthfile, "/tmp/ssh-XXXXXXXX", MAXPATHLEN);
274: temporarily_use_uid(pw->pw_uid);
275: if (mkdtemp(xauthfile) == NULL) {
276: restore_uid();
277: error("private X11 dir: mkdtemp %s failed: %s",
278: xauthfile, strerror(errno));
279: xfree(xauthfile);
280: xauthfile = NULL;
1.7 markus 281: /* XXXX remove listening channels */
1.1 markus 282: break;
283: }
284: strlcat(xauthfile, "/cookies", MAXPATHLEN);
285: open(xauthfile, O_RDWR|O_CREAT|O_EXCL, 0600);
286: restore_uid();
287: fatal_add_cleanup(xauthfile_cleanup_proc, NULL);
288: success = 1;
289: break;
290:
291: case SSH_CMSG_AGENT_REQUEST_FORWARDING:
292: if (no_agent_forwarding_flag || compat13) {
293: debug("Authentication agent forwarding not permitted for this authentication.");
294: break;
295: }
296: debug("Received authentication agent forwarding request.");
1.15 markus 297: success = auth_input_request_forwarding(pw);
1.1 markus 298: break;
299:
300: case SSH_CMSG_PORT_FORWARD_REQUEST:
301: if (no_port_forwarding_flag) {
302: debug("Port forwarding not permitted for this authentication.");
303: break;
304: }
305: debug("Received TCP/IP port forwarding request.");
1.12 markus 306: channel_input_port_forward_request(pw->pw_uid == 0, options.gateway_ports);
1.1 markus 307: success = 1;
308: break;
309:
310: case SSH_CMSG_MAX_PACKET_SIZE:
311: if (packet_set_maxsize(packet_get_int()) > 0)
312: success = 1;
313: break;
314:
315: case SSH_CMSG_EXEC_SHELL:
316: case SSH_CMSG_EXEC_CMD:
317: /* Set interactive/non-interactive mode. */
318: packet_set_interactive(have_pty || s->display != NULL,
319: options.keepalives);
320:
321: if (type == SSH_CMSG_EXEC_CMD) {
322: command = packet_get_string(&dlen);
323: debug("Exec command '%.500s'", command);
324: packet_integrity_check(plen, 4 + dlen, type);
325: } else {
326: command = NULL;
327: packet_integrity_check(plen, 0, type);
328: }
329: if (forced_command != NULL) {
330: command = forced_command;
331: debug("Forced command '%.500s'", forced_command);
332: }
333: if (have_pty)
334: do_exec_pty(s, command, pw);
335: else
336: do_exec_no_pty(s, command, pw);
337:
338: if (command != NULL)
339: xfree(command);
340: /* Cleanup user's local Xauthority file. */
341: if (xauthfile)
342: xauthfile_cleanup_proc(NULL);
343: return;
344:
345: default:
346: /*
347: * Any unknown messages in this phase are ignored,
348: * and a failure message is returned.
349: */
350: log("Unknown packet type received after authentication: %d", type);
351: }
352: packet_start(success ? SSH_SMSG_SUCCESS : SSH_SMSG_FAILURE);
353: packet_send();
354: packet_write_wait();
355:
356: /* Enable compression now that we have replied if appropriate. */
357: if (enable_compression_after_reply) {
358: enable_compression_after_reply = 0;
359: packet_start_compression(compression_level);
360: }
361: }
362: }
363:
364: /*
365: * This is called to fork and execute a command when we have no tty. This
366: * will call do_child from the child, and server_loop from the parent after
367: * setting up file descriptors and such.
368: */
1.4 markus 369: void
1.1 markus 370: do_exec_no_pty(Session *s, const char *command, struct passwd * pw)
371: {
372: int pid;
373:
374: #ifdef USE_PIPES
375: int pin[2], pout[2], perr[2];
376: /* Allocate pipes for communicating with the program. */
377: if (pipe(pin) < 0 || pipe(pout) < 0 || pipe(perr) < 0)
378: packet_disconnect("Could not create pipes: %.100s",
379: strerror(errno));
380: #else /* USE_PIPES */
381: int inout[2], err[2];
382: /* Uses socket pairs to communicate with the program. */
383: if (socketpair(AF_UNIX, SOCK_STREAM, 0, inout) < 0 ||
384: socketpair(AF_UNIX, SOCK_STREAM, 0, err) < 0)
385: packet_disconnect("Could not create socket pairs: %.100s",
386: strerror(errno));
387: #endif /* USE_PIPES */
388: if (s == NULL)
389: fatal("do_exec_no_pty: no session");
390:
1.9 markus 391: session_proctitle(s);
1.1 markus 392:
393: /* Fork the child. */
394: if ((pid = fork()) == 0) {
395: /* Child. Reinitialize the log since the pid has changed. */
396: log_init(__progname, options.log_level, options.log_facility, log_stderr);
397:
398: /*
399: * Create a new session and process group since the 4.4BSD
400: * setlogin() affects the entire process group.
401: */
402: if (setsid() < 0)
403: error("setsid failed: %.100s", strerror(errno));
404:
405: #ifdef USE_PIPES
406: /*
407: * Redirect stdin. We close the parent side of the socket
408: * pair, and make the child side the standard input.
409: */
410: close(pin[1]);
411: if (dup2(pin[0], 0) < 0)
412: perror("dup2 stdin");
413: close(pin[0]);
414:
415: /* Redirect stdout. */
416: close(pout[0]);
417: if (dup2(pout[1], 1) < 0)
418: perror("dup2 stdout");
419: close(pout[1]);
420:
421: /* Redirect stderr. */
422: close(perr[0]);
423: if (dup2(perr[1], 2) < 0)
424: perror("dup2 stderr");
425: close(perr[1]);
426: #else /* USE_PIPES */
427: /*
428: * Redirect stdin, stdout, and stderr. Stdin and stdout will
429: * use the same socket, as some programs (particularly rdist)
430: * seem to depend on it.
431: */
432: close(inout[1]);
433: close(err[1]);
434: if (dup2(inout[0], 0) < 0) /* stdin */
435: perror("dup2 stdin");
436: if (dup2(inout[0], 1) < 0) /* stdout. Note: same socket as stdin. */
437: perror("dup2 stdout");
438: if (dup2(err[0], 2) < 0) /* stderr */
439: perror("dup2 stderr");
440: #endif /* USE_PIPES */
441:
442: /* Do processing for the child (exec command etc). */
443: do_child(command, pw, NULL, s->display, s->auth_proto, s->auth_data, NULL);
444: /* NOTREACHED */
445: }
446: if (pid < 0)
447: packet_disconnect("fork failed: %.100s", strerror(errno));
448: s->pid = pid;
449: #ifdef USE_PIPES
450: /* We are the parent. Close the child sides of the pipes. */
451: close(pin[0]);
452: close(pout[1]);
453: close(perr[1]);
454:
1.2 markus 455: if (compat20) {
1.7 markus 456: session_set_fds(s, pin[1], pout[0], s->extended ? perr[0] : -1);
1.2 markus 457: } else {
458: /* Enter the interactive session. */
459: server_loop(pid, pin[1], pout[0], perr[0]);
460: /* server_loop has closed pin[1], pout[1], and perr[1]. */
461: }
1.1 markus 462: #else /* USE_PIPES */
463: /* We are the parent. Close the child sides of the socket pairs. */
464: close(inout[0]);
465: close(err[0]);
466:
467: /*
468: * Enter the interactive session. Note: server_loop must be able to
469: * handle the case that fdin and fdout are the same.
470: */
1.2 markus 471: if (compat20) {
1.7 markus 472: session_set_fds(s, inout[1], inout[1], s->extended ? err[1] : -1);
1.2 markus 473: } else {
474: server_loop(pid, inout[1], inout[1], err[1]);
475: /* server_loop has closed inout[1] and err[1]. */
476: }
1.1 markus 477: #endif /* USE_PIPES */
478: }
479:
480: /*
481: * This is called to fork and execute a command when we have a tty. This
482: * will call do_child from the child, and server_loop from the parent after
483: * setting up file descriptors, controlling tty, updating wtmp, utmp,
484: * lastlog, and other such operations.
485: */
1.4 markus 486: void
1.1 markus 487: do_exec_pty(Session *s, const char *command, struct passwd * pw)
488: {
489: FILE *f;
490: char buf[100], *time_string;
491: char line[256];
492: const char *hostname;
493: int fdout, ptyfd, ttyfd, ptymaster;
494: int quiet_login;
495: pid_t pid;
496: socklen_t fromlen;
497: struct sockaddr_storage from;
498: struct stat st;
499: time_t last_login_time;
500:
501: if (s == NULL)
502: fatal("do_exec_pty: no session");
503: ptyfd = s->ptyfd;
504: ttyfd = s->ttyfd;
505:
506: /* Get remote host name. */
507: hostname = get_canonical_hostname();
508:
509: /*
510: * Get the time when the user last logged in. Buf will be set to
511: * contain the hostname the last login was from.
512: */
513: if (!options.use_login) {
514: last_login_time = get_last_login_time(pw->pw_uid, pw->pw_name,
515: buf, sizeof(buf));
516: }
517:
518: /* Fork the child. */
519: if ((pid = fork()) == 0) {
520: pid = getpid();
521:
522: /* Child. Reinitialize the log because the pid has
523: changed. */
524: log_init(__progname, options.log_level, options.log_facility, log_stderr);
525:
526: /* Close the master side of the pseudo tty. */
527: close(ptyfd);
528:
529: /* Make the pseudo tty our controlling tty. */
530: pty_make_controlling_tty(&ttyfd, s->tty);
531:
532: /* Redirect stdin from the pseudo tty. */
533: if (dup2(ttyfd, fileno(stdin)) < 0)
534: error("dup2 stdin failed: %.100s", strerror(errno));
535:
536: /* Redirect stdout to the pseudo tty. */
537: if (dup2(ttyfd, fileno(stdout)) < 0)
538: error("dup2 stdin failed: %.100s", strerror(errno));
539:
540: /* Redirect stderr to the pseudo tty. */
541: if (dup2(ttyfd, fileno(stderr)) < 0)
542: error("dup2 stdin failed: %.100s", strerror(errno));
543:
544: /* Close the extra descriptor for the pseudo tty. */
545: close(ttyfd);
546:
1.11 markus 547: /* XXXX ? move to do_child() ??*/
1.1 markus 548: /*
549: * Get IP address of client. This is needed because we want
550: * to record where the user logged in from. If the
551: * connection is not a socket, let the ip address be 0.0.0.0.
552: */
553: memset(&from, 0, sizeof(from));
554: if (packet_connection_is_on_socket()) {
555: fromlen = sizeof(from);
556: if (getpeername(packet_get_connection_in(),
557: (struct sockaddr *) & from, &fromlen) < 0) {
558: debug("getpeername: %.100s", strerror(errno));
559: fatal_cleanup();
560: }
561: }
562: /* Record that there was a login on that terminal. */
563: record_login(pid, s->tty, pw->pw_name, pw->pw_uid, hostname,
564: (struct sockaddr *)&from);
565:
566: /* Check if .hushlogin exists. */
567: snprintf(line, sizeof line, "%.200s/.hushlogin", pw->pw_dir);
568: quiet_login = stat(line, &st) >= 0;
569:
570: /*
571: * If the user has logged in before, display the time of last
572: * login. However, don't display anything extra if a command
573: * has been specified (so that ssh can be used to execute
574: * commands on a remote machine without users knowing they
575: * are going to another machine). Login(1) will do this for
576: * us as well, so check if login(1) is used
577: */
578: if (command == NULL && last_login_time != 0 && !quiet_login &&
579: !options.use_login) {
580: /* Convert the date to a string. */
581: time_string = ctime(&last_login_time);
582: /* Remove the trailing newline. */
583: if (strchr(time_string, '\n'))
584: *strchr(time_string, '\n') = 0;
585: /* Display the last login time. Host if displayed
586: if known. */
587: if (strcmp(buf, "") == 0)
588: printf("Last login: %s\r\n", time_string);
589: else
590: printf("Last login: %s from %s\r\n", time_string, buf);
591: }
592: /*
593: * Print /etc/motd unless a command was specified or printing
594: * it was disabled in server options or login(1) will be
595: * used. Note that some machines appear to print it in
596: * /etc/profile or similar.
597: */
598: if (command == NULL && options.print_motd && !quiet_login &&
599: !options.use_login) {
600: /* Print /etc/motd if it exists. */
601: f = fopen("/etc/motd", "r");
602: if (f) {
603: while (fgets(line, sizeof(line), f))
604: fputs(line, stdout);
605: fclose(f);
606: }
607: }
608: /* Do common processing for the child, such as execing the command. */
1.14 deraadt 609: do_child(command, pw, s->term, s->display, s->auth_proto,
610: s->auth_data, s->tty);
1.1 markus 611: /* NOTREACHED */
612: }
613: if (pid < 0)
614: packet_disconnect("fork failed: %.100s", strerror(errno));
615: s->pid = pid;
616:
617: /* Parent. Close the slave side of the pseudo tty. */
618: close(ttyfd);
619:
620: /*
621: * Create another descriptor of the pty master side for use as the
622: * standard input. We could use the original descriptor, but this
623: * simplifies code in server_loop. The descriptor is bidirectional.
624: */
625: fdout = dup(ptyfd);
626: if (fdout < 0)
627: packet_disconnect("dup #1 failed: %.100s", strerror(errno));
628:
629: /* we keep a reference to the pty master */
630: ptymaster = dup(ptyfd);
631: if (ptymaster < 0)
632: packet_disconnect("dup #2 failed: %.100s", strerror(errno));
633: s->ptymaster = ptymaster;
634:
635: /* Enter interactive session. */
1.2 markus 636: if (compat20) {
637: session_set_fds(s, ptyfd, fdout, -1);
638: } else {
639: server_loop(pid, ptyfd, fdout, -1);
640: /* server_loop _has_ closed ptyfd and fdout. */
641: session_pty_cleanup(s);
642: }
1.1 markus 643: }
644:
645: /*
646: * Sets the value of the given variable in the environment. If the variable
647: * already exists, its value is overriden.
648: */
1.4 markus 649: void
1.1 markus 650: child_set_env(char ***envp, unsigned int *envsizep, const char *name,
651: const char *value)
652: {
653: unsigned int i, namelen;
654: char **env;
655:
656: /*
657: * Find the slot where the value should be stored. If the variable
658: * already exists, we reuse the slot; otherwise we append a new slot
659: * at the end of the array, expanding if necessary.
660: */
661: env = *envp;
662: namelen = strlen(name);
663: for (i = 0; env[i]; i++)
664: if (strncmp(env[i], name, namelen) == 0 && env[i][namelen] == '=')
665: break;
666: if (env[i]) {
667: /* Reuse the slot. */
668: xfree(env[i]);
669: } else {
670: /* New variable. Expand if necessary. */
671: if (i >= (*envsizep) - 1) {
672: (*envsizep) += 50;
673: env = (*envp) = xrealloc(env, (*envsizep) * sizeof(char *));
674: }
675: /* Need to set the NULL pointer at end of array beyond the new slot. */
676: env[i + 1] = NULL;
677: }
678:
679: /* Allocate space and format the variable in the appropriate slot. */
680: env[i] = xmalloc(strlen(name) + 1 + strlen(value) + 1);
681: snprintf(env[i], strlen(name) + 1 + strlen(value) + 1, "%s=%s", name, value);
682: }
683:
684: /*
685: * Reads environment variables from the given file and adds/overrides them
686: * into the environment. If the file does not exist, this does nothing.
687: * Otherwise, it must consist of empty lines, comments (line starts with '#')
688: * and assignments of the form name=value. No other forms are allowed.
689: */
1.4 markus 690: void
1.1 markus 691: read_environment_file(char ***env, unsigned int *envsize,
692: const char *filename)
693: {
694: FILE *f;
695: char buf[4096];
696: char *cp, *value;
697:
698: f = fopen(filename, "r");
699: if (!f)
700: return;
701:
702: while (fgets(buf, sizeof(buf), f)) {
703: for (cp = buf; *cp == ' ' || *cp == '\t'; cp++)
704: ;
705: if (!*cp || *cp == '#' || *cp == '\n')
706: continue;
707: if (strchr(cp, '\n'))
708: *strchr(cp, '\n') = '\0';
709: value = strchr(cp, '=');
710: if (value == NULL) {
711: fprintf(stderr, "Bad line in %.100s: %.200s\n", filename, buf);
712: continue;
713: }
1.14 deraadt 714: /*
715: * Replace the equals sign by nul, and advance value to
716: * the value string.
717: */
1.1 markus 718: *value = '\0';
719: value++;
720: child_set_env(env, envsize, cp, value);
721: }
722: fclose(f);
723: }
724:
725: /*
726: * Performs common processing for the child, such as setting up the
727: * environment, closing extra file descriptors, setting the user and group
728: * ids, and executing the command or shell.
729: */
1.4 markus 730: void
1.1 markus 731: do_child(const char *command, struct passwd * pw, const char *term,
732: const char *display, const char *auth_proto,
733: const char *auth_data, const char *ttyname)
734: {
735: const char *shell, *cp = NULL;
736: char buf[256];
1.16 markus 737: char cmd[1024];
1.1 markus 738: FILE *f;
739: unsigned int envsize, i;
740: char **env;
741: extern char **environ;
742: struct stat st;
743: char *argv[10];
1.17 markus 744:
745: /* login(1) is only called if we execute the login shell */
746: if (options.use_login && command != NULL)
747: options.use_login = 0;
1.1 markus 748:
749: f = fopen("/etc/nologin", "r");
750: if (f) {
751: /* /etc/nologin exists. Print its contents and exit. */
752: while (fgets(buf, sizeof(buf), f))
753: fputs(buf, stderr);
754: fclose(f);
755: if (pw->pw_uid != 0)
756: exit(254);
757: }
758: /* Set login name in the kernel. */
759: if (setlogin(pw->pw_name) < 0)
760: error("setlogin failed: %s", strerror(errno));
761:
762: /* Set uid, gid, and groups. */
763: /* Login(1) does this as well, and it needs uid 0 for the "-h"
764: switch, so we let login(1) to this for us. */
765: if (!options.use_login) {
766: if (getuid() == 0 || geteuid() == 0) {
767: if (setgid(pw->pw_gid) < 0) {
768: perror("setgid");
769: exit(1);
770: }
771: /* Initialize the group list. */
772: if (initgroups(pw->pw_name, pw->pw_gid) < 0) {
773: perror("initgroups");
774: exit(1);
775: }
776: endgrent();
777:
778: /* Permanently switch to the desired uid. */
779: permanently_set_uid(pw->pw_uid);
780: }
781: if (getuid() != pw->pw_uid || geteuid() != pw->pw_uid)
782: fatal("Failed to set uids to %d.", (int) pw->pw_uid);
783: }
784: /*
785: * Get the shell from the password data. An empty shell field is
786: * legal, and means /bin/sh.
787: */
788: shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell;
789:
790: #ifdef AFS
791: /* Try to get AFS tokens for the local cell. */
792: if (k_hasafs()) {
793: char cell[64];
794:
795: if (k_afs_cell_of_file(pw->pw_dir, cell, sizeof(cell)) == 0)
796: krb_afslog(cell, 0);
797:
798: krb_afslog(0, 0);
799: }
800: #endif /* AFS */
801:
802: /* Initialize the environment. */
803: envsize = 100;
804: env = xmalloc(envsize * sizeof(char *));
805: env[0] = NULL;
806:
807: if (!options.use_login) {
808: /* Set basic environment. */
809: child_set_env(&env, &envsize, "USER", pw->pw_name);
810: child_set_env(&env, &envsize, "LOGNAME", pw->pw_name);
811: child_set_env(&env, &envsize, "HOME", pw->pw_dir);
812: child_set_env(&env, &envsize, "PATH", _PATH_STDPATH);
813:
814: snprintf(buf, sizeof buf, "%.200s/%.50s",
815: _PATH_MAILDIR, pw->pw_name);
816: child_set_env(&env, &envsize, "MAIL", buf);
817:
818: /* Normal systems set SHELL by default. */
819: child_set_env(&env, &envsize, "SHELL", shell);
820: }
821: if (getenv("TZ"))
822: child_set_env(&env, &envsize, "TZ", getenv("TZ"));
823:
824: /* Set custom environment options from RSA authentication. */
825: while (custom_environment) {
826: struct envstring *ce = custom_environment;
827: char *s = ce->s;
828: int i;
829: for (i = 0; s[i] != '=' && s[i]; i++);
830: if (s[i] == '=') {
831: s[i] = 0;
832: child_set_env(&env, &envsize, s, s + i + 1);
833: }
834: custom_environment = ce->next;
835: xfree(ce->s);
836: xfree(ce);
837: }
838:
839: snprintf(buf, sizeof buf, "%.50s %d %d",
840: get_remote_ipaddr(), get_remote_port(), get_local_port());
841: child_set_env(&env, &envsize, "SSH_CLIENT", buf);
842:
843: if (ttyname)
844: child_set_env(&env, &envsize, "SSH_TTY", ttyname);
845: if (term)
846: child_set_env(&env, &envsize, "TERM", term);
847: if (display)
848: child_set_env(&env, &envsize, "DISPLAY", display);
849:
850: #ifdef KRB4
851: {
852: extern char *ticket;
853:
854: if (ticket)
855: child_set_env(&env, &envsize, "KRBTKFILE", ticket);
856: }
857: #endif /* KRB4 */
858:
859: if (xauthfile)
860: child_set_env(&env, &envsize, "XAUTHORITY", xauthfile);
861: if (auth_get_socket_name() != NULL)
862: child_set_env(&env, &envsize, SSH_AUTHSOCKET_ENV_NAME,
863: auth_get_socket_name());
864:
865: /* read $HOME/.ssh/environment. */
866: if (!options.use_login) {
1.14 deraadt 867: snprintf(buf, sizeof buf, "%.200s/.ssh/environment",
868: pw->pw_dir);
1.1 markus 869: read_environment_file(&env, &envsize, buf);
870: }
871: if (debug_flag) {
872: /* dump the environment */
873: fprintf(stderr, "Environment:\n");
874: for (i = 0; env[i]; i++)
875: fprintf(stderr, " %.200s\n", env[i]);
876: }
877: /*
878: * Close the connection descriptors; note that this is the child, and
879: * the server will still have the socket open, and it is important
880: * that we do not shutdown it. Note that the descriptors cannot be
881: * closed before building the environment, as we call
882: * get_remote_ipaddr there.
883: */
884: if (packet_get_connection_in() == packet_get_connection_out())
885: close(packet_get_connection_in());
886: else {
887: close(packet_get_connection_in());
888: close(packet_get_connection_out());
889: }
890: /*
891: * Close all descriptors related to channels. They will still remain
892: * open in the parent.
893: */
894: /* XXX better use close-on-exec? -markus */
895: channel_close_all();
896:
897: /*
898: * Close any extra file descriptors. Note that there may still be
899: * descriptors left by system functions. They will be closed later.
900: */
901: endpwent();
902:
903: /*
904: * Close any extra open file descriptors so that we don\'t have them
905: * hanging around in clients. Note that we want to do this after
906: * initgroups, because at least on Solaris 2.3 it leaves file
907: * descriptors open.
908: */
909: for (i = 3; i < 64; i++)
910: close(i);
911:
912: /* Change current directory to the user\'s home directory. */
913: if (chdir(pw->pw_dir) < 0)
914: fprintf(stderr, "Could not chdir to home directory %s: %s\n",
915: pw->pw_dir, strerror(errno));
916:
917: /*
918: * Must take new environment into use so that .ssh/rc, /etc/sshrc and
919: * xauth are run in the proper environment.
920: */
921: environ = env;
922:
923: /*
924: * Run $HOME/.ssh/rc, /etc/sshrc, or xauth (whichever is found first
925: * in this order).
926: */
927: if (!options.use_login) {
928: if (stat(SSH_USER_RC, &st) >= 0) {
929: if (debug_flag)
930: fprintf(stderr, "Running /bin/sh %s\n", SSH_USER_RC);
931:
932: f = popen("/bin/sh " SSH_USER_RC, "w");
933: if (f) {
934: if (auth_proto != NULL && auth_data != NULL)
935: fprintf(f, "%s %s\n", auth_proto, auth_data);
936: pclose(f);
937: } else
938: fprintf(stderr, "Could not run %s\n", SSH_USER_RC);
939: } else if (stat(SSH_SYSTEM_RC, &st) >= 0) {
940: if (debug_flag)
941: fprintf(stderr, "Running /bin/sh %s\n", SSH_SYSTEM_RC);
942:
943: f = popen("/bin/sh " SSH_SYSTEM_RC, "w");
944: if (f) {
945: if (auth_proto != NULL && auth_data != NULL)
946: fprintf(f, "%s %s\n", auth_proto, auth_data);
947: pclose(f);
948: } else
949: fprintf(stderr, "Could not run %s\n", SSH_SYSTEM_RC);
1.16 markus 950: } else if (options.xauth_location != NULL) {
1.1 markus 951: /* Add authority data to .Xauthority if appropriate. */
952: if (auth_proto != NULL && auth_data != NULL) {
1.13 markus 953: char *screen = strchr(display, ':');
954: if (debug_flag) {
1.14 deraadt 955: fprintf(stderr,
956: "Running %.100s add %.100s %.100s %.100s\n",
1.16 markus 957: options.xauth_location, display,
958: auth_proto, auth_data);
1.13 markus 959: if (screen != NULL)
1.14 deraadt 960: fprintf(stderr,
961: "Adding %.*s/unix%s %s %s\n",
962: screen-display, display,
963: screen, auth_proto, auth_data);
1.13 markus 964: }
1.16 markus 965: snprintf(cmd, sizeof cmd, "%s -q -",
966: options.xauth_location);
967: f = popen(cmd, "w");
1.1 markus 968: if (f) {
1.14 deraadt 969: fprintf(f, "add %s %s %s\n", display,
970: auth_proto, auth_data);
1.13 markus 971: if (screen != NULL)
972: fprintf(f, "add %.*s/unix%s %s %s\n",
1.14 deraadt 973: screen-display, display,
974: screen, auth_proto, auth_data);
1.1 markus 975: pclose(f);
1.16 markus 976: } else {
977: fprintf(stderr, "Could not run %s\n",
978: cmd);
979: }
1.1 markus 980: }
981: }
982: /* Get the last component of the shell name. */
983: cp = strrchr(shell, '/');
984: if (cp)
985: cp++;
986: else
987: cp = shell;
988: }
989: /*
990: * If we have no command, execute the shell. In this case, the shell
991: * name to be passed in argv[0] is preceded by '-' to indicate that
992: * this is a login shell.
993: */
994: if (!command) {
995: if (!options.use_login) {
996: char buf[256];
997:
998: /*
999: * Check for mail if we have a tty and it was enabled
1000: * in server options.
1001: */
1002: if (ttyname && options.check_mail) {
1003: char *mailbox;
1004: struct stat mailstat;
1005: mailbox = getenv("MAIL");
1006: if (mailbox != NULL) {
1.14 deraadt 1007: if (stat(mailbox, &mailstat) != 0 ||
1008: mailstat.st_size == 0)
1.1 markus 1009: printf("No mail.\n");
1010: else if (mailstat.st_mtime < mailstat.st_atime)
1011: printf("You have mail.\n");
1012: else
1013: printf("You have new mail.\n");
1014: }
1015: }
1016: /* Start the shell. Set initial character to '-'. */
1017: buf[0] = '-';
1018: strncpy(buf + 1, cp, sizeof(buf) - 1);
1019: buf[sizeof(buf) - 1] = 0;
1020:
1021: /* Execute the shell. */
1022: argv[0] = buf;
1023: argv[1] = NULL;
1024: execve(shell, argv, env);
1025:
1026: /* Executing the shell failed. */
1027: perror(shell);
1028: exit(1);
1029:
1030: } else {
1031: /* Launch login(1). */
1032:
1033: execl("/usr/bin/login", "login", "-h", get_remote_ipaddr(),
1034: "-p", "-f", "--", pw->pw_name, NULL);
1035:
1036: /* Login couldn't be executed, die. */
1037:
1038: perror("login");
1039: exit(1);
1040: }
1041: }
1042: /*
1043: * Execute the command using the user's shell. This uses the -c
1044: * option to execute the command.
1045: */
1046: argv[0] = (char *) cp;
1047: argv[1] = "-c";
1048: argv[2] = (char *) command;
1049: argv[3] = NULL;
1050: execve(shell, argv, env);
1051: perror(shell);
1052: exit(1);
1053: }
1054:
1055: Session *
1056: session_new(void)
1057: {
1058: int i;
1059: static int did_init = 0;
1060: if (!did_init) {
1061: debug("session_new: init");
1062: for(i = 0; i < MAX_SESSIONS; i++) {
1063: sessions[i].used = 0;
1064: sessions[i].self = i;
1065: }
1066: did_init = 1;
1067: }
1068: for(i = 0; i < MAX_SESSIONS; i++) {
1069: Session *s = &sessions[i];
1070: if (! s->used) {
1071: s->pid = 0;
1.7 markus 1072: s->extended = 0;
1.1 markus 1073: s->chanid = -1;
1074: s->ptyfd = -1;
1075: s->ttyfd = -1;
1076: s->term = NULL;
1077: s->pw = NULL;
1078: s->display = NULL;
1079: s->screen = 0;
1080: s->auth_data = NULL;
1081: s->auth_proto = NULL;
1082: s->used = 1;
1.7 markus 1083: s->pw = NULL;
1.1 markus 1084: debug("session_new: session %d", i);
1085: return s;
1086: }
1087: }
1088: return NULL;
1089: }
1090:
1091: void
1092: session_dump(void)
1093: {
1094: int i;
1095: for(i = 0; i < MAX_SESSIONS; i++) {
1096: Session *s = &sessions[i];
1097: debug("dump: used %d session %d %p channel %d pid %d",
1098: s->used,
1099: s->self,
1100: s,
1101: s->chanid,
1102: s->pid);
1103: }
1104: }
1105:
1.2 markus 1106: int
1107: session_open(int chanid)
1108: {
1109: Session *s = session_new();
1110: debug("session_open: channel %d", chanid);
1111: if (s == NULL) {
1112: error("no more sessions");
1113: return 0;
1114: }
1.7 markus 1115: s->pw = auth_get_user();
1116: if (s->pw == NULL)
1117: fatal("no user for session %i", s->self);
1.2 markus 1118: debug("session_open: session %d: link with channel %d", s->self, chanid);
1119: s->chanid = chanid;
1120: return 1;
1121: }
1122:
1123: Session *
1124: session_by_channel(int id)
1125: {
1126: int i;
1127: for(i = 0; i < MAX_SESSIONS; i++) {
1128: Session *s = &sessions[i];
1129: if (s->used && s->chanid == id) {
1130: debug("session_by_channel: session %d channel %d", i, id);
1131: return s;
1132: }
1133: }
1134: debug("session_by_channel: unknown channel %d", id);
1135: session_dump();
1136: return NULL;
1137: }
1138:
1139: Session *
1140: session_by_pid(pid_t pid)
1141: {
1142: int i;
1143: debug("session_by_pid: pid %d", pid);
1144: for(i = 0; i < MAX_SESSIONS; i++) {
1145: Session *s = &sessions[i];
1146: if (s->used && s->pid == pid)
1147: return s;
1148: }
1149: error("session_by_pid: unknown pid %d", pid);
1150: session_dump();
1151: return NULL;
1152: }
1153:
1154: int
1155: session_window_change_req(Session *s)
1156: {
1157: s->col = packet_get_int();
1158: s->row = packet_get_int();
1159: s->xpixel = packet_get_int();
1160: s->ypixel = packet_get_int();
1.3 markus 1161: packet_done();
1.2 markus 1162: pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
1163: return 1;
1164: }
1165:
1166: int
1167: session_pty_req(Session *s)
1168: {
1169: unsigned int len;
1.3 markus 1170: char *term_modes; /* encoded terminal modes */
1.2 markus 1171:
1.19 markus 1172: if (no_pty_flag)
1173: return 0;
1.2 markus 1174: if (s->ttyfd != -1)
1.3 markus 1175: return 0;
1.2 markus 1176: s->term = packet_get_string(&len);
1177: s->col = packet_get_int();
1178: s->row = packet_get_int();
1179: s->xpixel = packet_get_int();
1180: s->ypixel = packet_get_int();
1.3 markus 1181: term_modes = packet_get_string(&len);
1182: packet_done();
1.2 markus 1183:
1184: if (strcmp(s->term, "") == 0) {
1185: xfree(s->term);
1186: s->term = NULL;
1187: }
1188: /* Allocate a pty and open it. */
1189: if (!pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty))) {
1190: xfree(s->term);
1191: s->term = NULL;
1192: s->ptyfd = -1;
1193: s->ttyfd = -1;
1194: error("session_pty_req: session %d alloc failed", s->self);
1.3 markus 1195: xfree(term_modes);
1196: return 0;
1.2 markus 1197: }
1198: debug("session_pty_req: session %d alloc %s", s->self, s->tty);
1199: /*
1200: * Add a cleanup function to clear the utmp entry and record logout
1201: * time in case we call fatal() (e.g., the connection gets closed).
1202: */
1203: fatal_add_cleanup(pty_cleanup_proc, (void *)s);
1204: pty_setowner(s->pw, s->tty);
1205: /* Get window size from the packet. */
1206: pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
1207:
1.9 markus 1208: session_proctitle(s);
1209:
1.3 markus 1210: /* XXX parse and set terminal modes */
1211: xfree(term_modes);
1.2 markus 1212: return 1;
1213: }
1214:
1.7 markus 1215: int
1216: session_subsystem_req(Session *s)
1217: {
1218: unsigned int len;
1219: int success = 0;
1220: char *subsys = packet_get_string(&len);
1.18 jakob 1221: int i;
1.7 markus 1222:
1223: packet_done();
1224: log("subsystem request for %s", subsys);
1.18 jakob 1225:
1226: for (i = 0; i < options.num_subsystems; i++) {
1227: if(strcmp(subsys, options.subsystem_name[i]) == 0) {
1228: debug("subsystem: exec() %s", options.subsystem_command[i]);
1229: do_exec_no_pty(s, options.subsystem_command[i], s->pw);
1230: success = 1;
1231: }
1232: }
1233:
1234: if (!success)
1235: log("subsystem request for %s failed, subsystem not found", subsys);
1.7 markus 1236:
1237: xfree(subsys);
1238: return success;
1239: }
1240:
1241: int
1242: session_x11_req(Session *s)
1243: {
1.22 deraadt 1244: if (no_x11_forwarding_flag) {
1.19 markus 1245: debug("X11 forwarding disabled in user configuration file.");
1246: return 0;
1247: }
1.7 markus 1248: if (!options.x11_forwarding) {
1249: debug("X11 forwarding disabled in server configuration file.");
1250: return 0;
1251: }
1252: if (xauthfile != NULL) {
1253: debug("X11 fwd already started.");
1254: return 0;
1255: }
1256:
1257: debug("Received request for X11 forwarding with auth spoofing.");
1258: if (s->display != NULL)
1259: packet_disconnect("Protocol error: X11 display already set.");
1260:
1261: s->single_connection = packet_get_char();
1262: s->auth_proto = packet_get_string(NULL);
1263: s->auth_data = packet_get_string(NULL);
1264: s->screen = packet_get_int();
1265: packet_done();
1266:
1267: s->display = x11_create_display_inet(s->screen, options.x11_display_offset);
1268: if (s->display == NULL) {
1269: xfree(s->auth_proto);
1270: xfree(s->auth_data);
1271: return 0;
1272: }
1273: xauthfile = xmalloc(MAXPATHLEN);
1274: strlcpy(xauthfile, "/tmp/ssh-XXXXXXXX", MAXPATHLEN);
1275: temporarily_use_uid(s->pw->pw_uid);
1276: if (mkdtemp(xauthfile) == NULL) {
1277: restore_uid();
1278: error("private X11 dir: mkdtemp %s failed: %s",
1279: xauthfile, strerror(errno));
1280: xfree(xauthfile);
1281: xauthfile = NULL;
1282: xfree(s->auth_proto);
1283: xfree(s->auth_data);
1284: /* XXXX remove listening channels */
1285: return 0;
1286: }
1287: strlcat(xauthfile, "/cookies", MAXPATHLEN);
1288: open(xauthfile, O_RDWR|O_CREAT|O_EXCL, 0600);
1289: restore_uid();
1290: fatal_add_cleanup(xauthfile_cleanup_proc, s);
1291: return 1;
1292: }
1293:
1.19 markus 1294: int
1295: session_shell_req(Session *s)
1296: {
1297: /* if forced_command == NULL, the shell is execed */
1298: char *shell = forced_command;
1299: packet_done();
1300: s->extended = 1;
1301: if (s->ttyfd == -1)
1302: do_exec_no_pty(s, shell, s->pw);
1303: else
1304: do_exec_pty(s, shell, s->pw);
1305: return 1;
1306: }
1307:
1308: int
1309: session_exec_req(Session *s)
1310: {
1.20 markus 1311: unsigned int len;
1.19 markus 1312: char *command = packet_get_string(&len);
1313: packet_done();
1314: if (forced_command) {
1315: xfree(command);
1316: command = forced_command;
1317: debug("Forced command '%.500s'", forced_command);
1318: }
1319: s->extended = 1;
1320: if (s->ttyfd == -1)
1321: do_exec_no_pty(s, command, s->pw);
1322: else
1323: do_exec_pty(s, command, s->pw);
1324: if (forced_command == NULL)
1325: xfree(command);
1326: return 1;
1327: }
1328:
1.2 markus 1329: void
1330: session_input_channel_req(int id, void *arg)
1331: {
1332: unsigned int len;
1333: int reply;
1334: int success = 0;
1335: char *rtype;
1336: Session *s;
1337: Channel *c;
1338:
1339: rtype = packet_get_string(&len);
1340: reply = packet_get_char();
1341:
1342: s = session_by_channel(id);
1343: if (s == NULL)
1344: fatal("session_input_channel_req: channel %d: no session", id);
1345: c = channel_lookup(id);
1346: if (c == NULL)
1347: fatal("session_input_channel_req: channel %d: bad channel", id);
1348:
1349: debug("session_input_channel_req: session %d channel %d request %s reply %d",
1350: s->self, id, rtype, reply);
1351:
1352: /*
1353: * a session is in LARVAL state until a shell
1354: * or programm is executed
1355: */
1356: if (c->type == SSH_CHANNEL_LARVAL) {
1357: if (strcmp(rtype, "shell") == 0) {
1.19 markus 1358: success = session_shell_req(s);
1.2 markus 1359: } else if (strcmp(rtype, "exec") == 0) {
1.19 markus 1360: success = session_exec_req(s);
1.2 markus 1361: } else if (strcmp(rtype, "pty-req") == 0) {
1.3 markus 1362: success = session_pty_req(s);
1.7 markus 1363: } else if (strcmp(rtype, "x11-req") == 0) {
1364: success = session_x11_req(s);
1365: } else if (strcmp(rtype, "subsystem") == 0) {
1366: success = session_subsystem_req(s);
1.2 markus 1367: }
1368: }
1369: if (strcmp(rtype, "window-change") == 0) {
1370: success = session_window_change_req(s);
1371: }
1372:
1373: if (reply) {
1374: packet_start(success ?
1375: SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
1376: packet_put_int(c->remote_id);
1377: packet_send();
1378: }
1379: xfree(rtype);
1380: }
1381:
1382: void
1383: session_set_fds(Session *s, int fdin, int fdout, int fderr)
1384: {
1385: if (!compat20)
1386: fatal("session_set_fds: called for proto != 2.0");
1387: /*
1388: * now that have a child and a pipe to the child,
1389: * we can activate our channel and register the fd's
1390: */
1391: if (s->chanid == -1)
1392: fatal("no channel for session %d", s->self);
1393: channel_set_fds(s->chanid,
1394: fdout, fdin, fderr,
1395: fderr == -1 ? CHAN_EXTENDED_IGNORE : CHAN_EXTENDED_READ);
1396: }
1397:
1.1 markus 1398: void
1399: session_pty_cleanup(Session *s)
1400: {
1401: if (s == NULL || s->ttyfd == -1)
1402: return;
1403:
1404: debug("session_pty_cleanup: session %i release %s", s->self, s->tty);
1405:
1406: /* Cancel the cleanup function. */
1407: fatal_remove_cleanup(pty_cleanup_proc, (void *)s);
1408:
1409: /* Record that the user has logged out. */
1410: record_logout(s->pid, s->tty);
1411:
1412: /* Release the pseudo-tty. */
1413: pty_release(s->tty);
1414:
1415: /*
1416: * Close the server side of the socket pairs. We must do this after
1417: * the pty cleanup, so that another process doesn't get this pty
1418: * while we're still cleaning up.
1419: */
1420: if (close(s->ptymaster) < 0)
1421: error("close(s->ptymaster): %s", strerror(errno));
1.2 markus 1422: }
1423:
1424: void
1425: session_exit_message(Session *s, int status)
1426: {
1427: Channel *c;
1428: if (s == NULL)
1429: fatal("session_close: no session");
1430: c = channel_lookup(s->chanid);
1431: if (c == NULL)
1432: fatal("session_close: session %d: no channel %d",
1433: s->self, s->chanid);
1434: debug("session_exit_message: session %d channel %d pid %d",
1435: s->self, s->chanid, s->pid);
1436:
1437: if (WIFEXITED(status)) {
1438: channel_request_start(s->chanid,
1439: "exit-status", 0);
1440: packet_put_int(WEXITSTATUS(status));
1441: packet_send();
1442: } else if (WIFSIGNALED(status)) {
1443: channel_request_start(s->chanid,
1444: "exit-signal", 0);
1445: packet_put_int(WTERMSIG(status));
1446: packet_put_char(WCOREDUMP(status));
1447: packet_put_cstring("");
1448: packet_put_cstring("");
1449: packet_send();
1450: } else {
1451: /* Some weird exit cause. Just exit. */
1452: packet_disconnect("wait returned status %04x.", status);
1453: }
1454:
1455: /* disconnect channel */
1456: debug("session_exit_message: release channel %d", s->chanid);
1457: channel_cancel_cleanup(s->chanid);
1.5 markus 1458: /*
1459: * emulate a write failure with 'chan_write_failed', nobody will be
1460: * interested in data we write.
1461: * Note that we must not call 'chan_read_failed', since there could
1462: * be some more data waiting in the pipe.
1463: */
1.8 markus 1464: if (c->ostate != CHAN_OUTPUT_CLOSED)
1465: chan_write_failed(c);
1.2 markus 1466: s->chanid = -1;
1467: }
1468:
1469: void
1470: session_free(Session *s)
1471: {
1472: debug("session_free: session %d pid %d", s->self, s->pid);
1473: if (s->term)
1474: xfree(s->term);
1475: if (s->display)
1476: xfree(s->display);
1477: if (s->auth_data)
1478: xfree(s->auth_data);
1479: if (s->auth_proto)
1480: xfree(s->auth_proto);
1481: s->used = 0;
1482: }
1483:
1484: void
1485: session_close(Session *s)
1486: {
1487: session_pty_cleanup(s);
1488: session_free(s);
1.9 markus 1489: session_proctitle(s);
1.2 markus 1490: }
1491:
1492: void
1493: session_close_by_pid(pid_t pid, int status)
1494: {
1495: Session *s = session_by_pid(pid);
1496: if (s == NULL) {
1497: debug("session_close_by_pid: no session for pid %d", s->pid);
1498: return;
1499: }
1500: if (s->chanid != -1)
1501: session_exit_message(s, status);
1502: session_close(s);
1503: }
1504:
1505: /*
1506: * this is called when a channel dies before
1507: * the session 'child' itself dies
1508: */
1509: void
1510: session_close_by_channel(int id, void *arg)
1511: {
1512: Session *s = session_by_channel(id);
1513: if (s == NULL) {
1514: debug("session_close_by_channel: no session for channel %d", id);
1515: return;
1516: }
1517: /* disconnect channel */
1518: channel_cancel_cleanup(s->chanid);
1519: s->chanid = -1;
1520:
1521: debug("session_close_by_channel: channel %d kill %d", id, s->pid);
1522: if (s->pid == 0) {
1523: /* close session immediately */
1524: session_close(s);
1525: } else {
1526: /* notify child, delay session cleanup */
1527: if (kill(s->pid, (s->ttyfd == -1) ? SIGTERM : SIGHUP) < 0)
1528: error("session_close_by_channel: kill %d: %s",
1529: s->pid, strerror(errno));
1530: }
1.9 markus 1531: }
1532:
1533: char *
1534: session_tty_list(void)
1535: {
1536: static char buf[1024];
1537: int i;
1538: buf[0] = '\0';
1539: for(i = 0; i < MAX_SESSIONS; i++) {
1540: Session *s = &sessions[i];
1541: if (s->used && s->ttyfd != -1) {
1542: if (buf[0] != '\0')
1543: strlcat(buf, ",", sizeof buf);
1544: strlcat(buf, strrchr(s->tty, '/') + 1, sizeof buf);
1545: }
1546: }
1547: if (buf[0] == '\0')
1548: strlcpy(buf, "notty", sizeof buf);
1549: return buf;
1550: }
1551:
1552: void
1553: session_proctitle(Session *s)
1554: {
1555: if (s->pw == NULL)
1556: error("no user for session %d", s->self);
1557: else
1558: setproctitle("%s@%s", s->pw->pw_name, session_tty_list());
1.2 markus 1559: }
1560:
1561: void
1562: do_authenticated2(void)
1563: {
1564: /*
1565: * Cancel the alarm we set to limit the time taken for
1566: * authentication.
1567: */
1568: alarm(0);
1.23 ! deraadt 1569: if (startup_pipe != -1) {
! 1570: close(startup_pipe);
! 1571: startup_pipe = -1;
! 1572: }
1.2 markus 1573: server_loop2();
1.7 markus 1574: if (xauthfile)
1575: xauthfile_cleanup_proc(NULL);
1.1 markus 1576: }
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