Annotation of src/usr.bin/ssh/session.c, Revision 1.22
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"
1.22 ! deraadt 11: RCSID("$OpenBSD: session.c,v 1.21 2000/06/26 21:59:18 markus 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);
1.21 markus 150: close(startup_pipe);
1.1 markus 151:
152: /*
153: * Inform the channel mechanism that we are the server side and that
154: * the client may request to connect to any port at all. (The user
155: * could do it anyway, and we wouldn\'t know what is permitted except
156: * by the client telling us, so we can equally well trust the client
157: * not to request anything bogus.)
158: */
159: if (!no_port_forwarding_flag)
160: channel_permit_all_opens();
161:
162: s = session_new();
1.7 markus 163: s->pw = pw;
1.1 markus 164:
165: /*
166: * We stay in this loop until the client requests to execute a shell
167: * or a command.
168: */
169: for (;;) {
170: int success = 0;
171:
172: /* Get a packet from the client. */
173: type = packet_read(&plen);
174:
175: /* Process the packet. */
176: switch (type) {
177: case SSH_CMSG_REQUEST_COMPRESSION:
178: packet_integrity_check(plen, 4, type);
179: compression_level = packet_get_int();
180: if (compression_level < 1 || compression_level > 9) {
181: packet_send_debug("Received illegal compression level %d.",
182: compression_level);
183: break;
184: }
185: /* Enable compression after we have responded with SUCCESS. */
186: enable_compression_after_reply = 1;
187: success = 1;
188: break;
189:
190: case SSH_CMSG_REQUEST_PTY:
191: if (no_pty_flag) {
192: debug("Allocating a pty not permitted for this authentication.");
193: break;
194: }
195: if (have_pty)
196: packet_disconnect("Protocol error: you already have a pty.");
197:
198: debug("Allocating pty.");
199:
200: /* Allocate a pty and open it. */
201: if (!pty_allocate(&s->ptyfd, &s->ttyfd, s->tty,
202: sizeof(s->tty))) {
203: error("Failed to allocate pty.");
204: break;
205: }
206: fatal_add_cleanup(pty_cleanup_proc, (void *)s);
207: pty_setowner(pw, s->tty);
208:
209: /* Get TERM from the packet. Note that the value may be of arbitrary length. */
210: s->term = packet_get_string(&dlen);
211: packet_integrity_check(dlen, strlen(s->term), type);
212: /* packet_integrity_check(plen, 4 + dlen + 4*4 + n_bytes, type); */
213: /* Remaining bytes */
214: n_bytes = plen - (4 + dlen + 4 * 4);
215:
216: if (strcmp(s->term, "") == 0) {
217: xfree(s->term);
218: s->term = NULL;
219: }
220: /* Get window size from the packet. */
221: s->row = packet_get_int();
222: s->col = packet_get_int();
223: s->xpixel = packet_get_int();
224: s->ypixel = packet_get_int();
225: pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
226:
227: /* Get tty modes from the packet. */
228: tty_parse_modes(s->ttyfd, &n_bytes);
229: packet_integrity_check(plen, 4 + dlen + 4 * 4 + n_bytes, type);
1.10 markus 230:
231: session_proctitle(s);
1.1 markus 232:
233: /* Indicate that we now have a pty. */
234: success = 1;
235: have_pty = 1;
236: break;
237:
238: case SSH_CMSG_X11_REQUEST_FORWARDING:
239: if (!options.x11_forwarding) {
240: packet_send_debug("X11 forwarding disabled in server configuration file.");
241: break;
242: }
1.16 markus 243: if (!options.xauth_location) {
244: packet_send_debug("No xauth program; cannot forward with spoofing.");
245: break;
246: }
1.1 markus 247: if (no_x11_forwarding_flag) {
248: packet_send_debug("X11 forwarding not permitted for this authentication.");
249: break;
250: }
251: debug("Received request for X11 forwarding with auth spoofing.");
252: if (s->display != NULL)
253: packet_disconnect("Protocol error: X11 display already set.");
254:
255: s->auth_proto = packet_get_string(&proto_len);
256: s->auth_data = packet_get_string(&data_len);
257: packet_integrity_check(plen, 4 + proto_len + 4 + data_len + 4, type);
258:
259: if (packet_get_protocol_flags() & SSH_PROTOFLAG_SCREEN_NUMBER)
260: s->screen = packet_get_int();
261: else
262: s->screen = 0;
263: s->display = x11_create_display_inet(s->screen, options.x11_display_offset);
264:
265: if (s->display == NULL)
266: break;
267:
268: /* Setup to always have a local .Xauthority. */
269: xauthfile = xmalloc(MAXPATHLEN);
270: strlcpy(xauthfile, "/tmp/ssh-XXXXXXXX", MAXPATHLEN);
271: temporarily_use_uid(pw->pw_uid);
272: if (mkdtemp(xauthfile) == NULL) {
273: restore_uid();
274: error("private X11 dir: mkdtemp %s failed: %s",
275: xauthfile, strerror(errno));
276: xfree(xauthfile);
277: xauthfile = NULL;
1.7 markus 278: /* XXXX remove listening channels */
1.1 markus 279: break;
280: }
281: strlcat(xauthfile, "/cookies", MAXPATHLEN);
282: open(xauthfile, O_RDWR|O_CREAT|O_EXCL, 0600);
283: restore_uid();
284: fatal_add_cleanup(xauthfile_cleanup_proc, NULL);
285: success = 1;
286: break;
287:
288: case SSH_CMSG_AGENT_REQUEST_FORWARDING:
289: if (no_agent_forwarding_flag || compat13) {
290: debug("Authentication agent forwarding not permitted for this authentication.");
291: break;
292: }
293: debug("Received authentication agent forwarding request.");
1.15 markus 294: success = auth_input_request_forwarding(pw);
1.1 markus 295: break;
296:
297: case SSH_CMSG_PORT_FORWARD_REQUEST:
298: if (no_port_forwarding_flag) {
299: debug("Port forwarding not permitted for this authentication.");
300: break;
301: }
302: debug("Received TCP/IP port forwarding request.");
1.12 markus 303: channel_input_port_forward_request(pw->pw_uid == 0, options.gateway_ports);
1.1 markus 304: success = 1;
305: break;
306:
307: case SSH_CMSG_MAX_PACKET_SIZE:
308: if (packet_set_maxsize(packet_get_int()) > 0)
309: success = 1;
310: break;
311:
312: case SSH_CMSG_EXEC_SHELL:
313: case SSH_CMSG_EXEC_CMD:
314: /* Set interactive/non-interactive mode. */
315: packet_set_interactive(have_pty || s->display != NULL,
316: options.keepalives);
317:
318: if (type == SSH_CMSG_EXEC_CMD) {
319: command = packet_get_string(&dlen);
320: debug("Exec command '%.500s'", command);
321: packet_integrity_check(plen, 4 + dlen, type);
322: } else {
323: command = NULL;
324: packet_integrity_check(plen, 0, type);
325: }
326: if (forced_command != NULL) {
327: command = forced_command;
328: debug("Forced command '%.500s'", forced_command);
329: }
330: if (have_pty)
331: do_exec_pty(s, command, pw);
332: else
333: do_exec_no_pty(s, command, pw);
334:
335: if (command != NULL)
336: xfree(command);
337: /* Cleanup user's local Xauthority file. */
338: if (xauthfile)
339: xauthfile_cleanup_proc(NULL);
340: return;
341:
342: default:
343: /*
344: * Any unknown messages in this phase are ignored,
345: * and a failure message is returned.
346: */
347: log("Unknown packet type received after authentication: %d", type);
348: }
349: packet_start(success ? SSH_SMSG_SUCCESS : SSH_SMSG_FAILURE);
350: packet_send();
351: packet_write_wait();
352:
353: /* Enable compression now that we have replied if appropriate. */
354: if (enable_compression_after_reply) {
355: enable_compression_after_reply = 0;
356: packet_start_compression(compression_level);
357: }
358: }
359: }
360:
361: /*
362: * This is called to fork and execute a command when we have no tty. This
363: * will call do_child from the child, and server_loop from the parent after
364: * setting up file descriptors and such.
365: */
1.4 markus 366: void
1.1 markus 367: do_exec_no_pty(Session *s, const char *command, struct passwd * pw)
368: {
369: int pid;
370:
371: #ifdef USE_PIPES
372: int pin[2], pout[2], perr[2];
373: /* Allocate pipes for communicating with the program. */
374: if (pipe(pin) < 0 || pipe(pout) < 0 || pipe(perr) < 0)
375: packet_disconnect("Could not create pipes: %.100s",
376: strerror(errno));
377: #else /* USE_PIPES */
378: int inout[2], err[2];
379: /* Uses socket pairs to communicate with the program. */
380: if (socketpair(AF_UNIX, SOCK_STREAM, 0, inout) < 0 ||
381: socketpair(AF_UNIX, SOCK_STREAM, 0, err) < 0)
382: packet_disconnect("Could not create socket pairs: %.100s",
383: strerror(errno));
384: #endif /* USE_PIPES */
385: if (s == NULL)
386: fatal("do_exec_no_pty: no session");
387:
1.9 markus 388: session_proctitle(s);
1.1 markus 389:
390: /* Fork the child. */
391: if ((pid = fork()) == 0) {
392: /* Child. Reinitialize the log since the pid has changed. */
393: log_init(__progname, options.log_level, options.log_facility, log_stderr);
394:
395: /*
396: * Create a new session and process group since the 4.4BSD
397: * setlogin() affects the entire process group.
398: */
399: if (setsid() < 0)
400: error("setsid failed: %.100s", strerror(errno));
401:
402: #ifdef USE_PIPES
403: /*
404: * Redirect stdin. We close the parent side of the socket
405: * pair, and make the child side the standard input.
406: */
407: close(pin[1]);
408: if (dup2(pin[0], 0) < 0)
409: perror("dup2 stdin");
410: close(pin[0]);
411:
412: /* Redirect stdout. */
413: close(pout[0]);
414: if (dup2(pout[1], 1) < 0)
415: perror("dup2 stdout");
416: close(pout[1]);
417:
418: /* Redirect stderr. */
419: close(perr[0]);
420: if (dup2(perr[1], 2) < 0)
421: perror("dup2 stderr");
422: close(perr[1]);
423: #else /* USE_PIPES */
424: /*
425: * Redirect stdin, stdout, and stderr. Stdin and stdout will
426: * use the same socket, as some programs (particularly rdist)
427: * seem to depend on it.
428: */
429: close(inout[1]);
430: close(err[1]);
431: if (dup2(inout[0], 0) < 0) /* stdin */
432: perror("dup2 stdin");
433: if (dup2(inout[0], 1) < 0) /* stdout. Note: same socket as stdin. */
434: perror("dup2 stdout");
435: if (dup2(err[0], 2) < 0) /* stderr */
436: perror("dup2 stderr");
437: #endif /* USE_PIPES */
438:
439: /* Do processing for the child (exec command etc). */
440: do_child(command, pw, NULL, s->display, s->auth_proto, s->auth_data, NULL);
441: /* NOTREACHED */
442: }
443: if (pid < 0)
444: packet_disconnect("fork failed: %.100s", strerror(errno));
445: s->pid = pid;
446: #ifdef USE_PIPES
447: /* We are the parent. Close the child sides of the pipes. */
448: close(pin[0]);
449: close(pout[1]);
450: close(perr[1]);
451:
1.2 markus 452: if (compat20) {
1.7 markus 453: session_set_fds(s, pin[1], pout[0], s->extended ? perr[0] : -1);
1.2 markus 454: } else {
455: /* Enter the interactive session. */
456: server_loop(pid, pin[1], pout[0], perr[0]);
457: /* server_loop has closed pin[1], pout[1], and perr[1]. */
458: }
1.1 markus 459: #else /* USE_PIPES */
460: /* We are the parent. Close the child sides of the socket pairs. */
461: close(inout[0]);
462: close(err[0]);
463:
464: /*
465: * Enter the interactive session. Note: server_loop must be able to
466: * handle the case that fdin and fdout are the same.
467: */
1.2 markus 468: if (compat20) {
1.7 markus 469: session_set_fds(s, inout[1], inout[1], s->extended ? err[1] : -1);
1.2 markus 470: } else {
471: server_loop(pid, inout[1], inout[1], err[1]);
472: /* server_loop has closed inout[1] and err[1]. */
473: }
1.1 markus 474: #endif /* USE_PIPES */
475: }
476:
477: /*
478: * This is called to fork and execute a command when we have a tty. This
479: * will call do_child from the child, and server_loop from the parent after
480: * setting up file descriptors, controlling tty, updating wtmp, utmp,
481: * lastlog, and other such operations.
482: */
1.4 markus 483: void
1.1 markus 484: do_exec_pty(Session *s, const char *command, struct passwd * pw)
485: {
486: FILE *f;
487: char buf[100], *time_string;
488: char line[256];
489: const char *hostname;
490: int fdout, ptyfd, ttyfd, ptymaster;
491: int quiet_login;
492: pid_t pid;
493: socklen_t fromlen;
494: struct sockaddr_storage from;
495: struct stat st;
496: time_t last_login_time;
497:
498: if (s == NULL)
499: fatal("do_exec_pty: no session");
500: ptyfd = s->ptyfd;
501: ttyfd = s->ttyfd;
502:
503: /* Get remote host name. */
504: hostname = get_canonical_hostname();
505:
506: /*
507: * Get the time when the user last logged in. Buf will be set to
508: * contain the hostname the last login was from.
509: */
510: if (!options.use_login) {
511: last_login_time = get_last_login_time(pw->pw_uid, pw->pw_name,
512: buf, sizeof(buf));
513: }
514:
515: /* Fork the child. */
516: if ((pid = fork()) == 0) {
517: pid = getpid();
518:
519: /* Child. Reinitialize the log because the pid has
520: changed. */
521: log_init(__progname, options.log_level, options.log_facility, log_stderr);
522:
523: /* Close the master side of the pseudo tty. */
524: close(ptyfd);
525:
526: /* Make the pseudo tty our controlling tty. */
527: pty_make_controlling_tty(&ttyfd, s->tty);
528:
529: /* Redirect stdin from the pseudo tty. */
530: if (dup2(ttyfd, fileno(stdin)) < 0)
531: error("dup2 stdin failed: %.100s", strerror(errno));
532:
533: /* Redirect stdout to the pseudo tty. */
534: if (dup2(ttyfd, fileno(stdout)) < 0)
535: error("dup2 stdin failed: %.100s", strerror(errno));
536:
537: /* Redirect stderr to the pseudo tty. */
538: if (dup2(ttyfd, fileno(stderr)) < 0)
539: error("dup2 stdin failed: %.100s", strerror(errno));
540:
541: /* Close the extra descriptor for the pseudo tty. */
542: close(ttyfd);
543:
1.11 markus 544: /* XXXX ? move to do_child() ??*/
1.1 markus 545: /*
546: * Get IP address of client. This is needed because we want
547: * to record where the user logged in from. If the
548: * connection is not a socket, let the ip address be 0.0.0.0.
549: */
550: memset(&from, 0, sizeof(from));
551: if (packet_connection_is_on_socket()) {
552: fromlen = sizeof(from);
553: if (getpeername(packet_get_connection_in(),
554: (struct sockaddr *) & from, &fromlen) < 0) {
555: debug("getpeername: %.100s", strerror(errno));
556: fatal_cleanup();
557: }
558: }
559: /* Record that there was a login on that terminal. */
560: record_login(pid, s->tty, pw->pw_name, pw->pw_uid, hostname,
561: (struct sockaddr *)&from);
562:
563: /* Check if .hushlogin exists. */
564: snprintf(line, sizeof line, "%.200s/.hushlogin", pw->pw_dir);
565: quiet_login = stat(line, &st) >= 0;
566:
567: /*
568: * If the user has logged in before, display the time of last
569: * login. However, don't display anything extra if a command
570: * has been specified (so that ssh can be used to execute
571: * commands on a remote machine without users knowing they
572: * are going to another machine). Login(1) will do this for
573: * us as well, so check if login(1) is used
574: */
575: if (command == NULL && last_login_time != 0 && !quiet_login &&
576: !options.use_login) {
577: /* Convert the date to a string. */
578: time_string = ctime(&last_login_time);
579: /* Remove the trailing newline. */
580: if (strchr(time_string, '\n'))
581: *strchr(time_string, '\n') = 0;
582: /* Display the last login time. Host if displayed
583: if known. */
584: if (strcmp(buf, "") == 0)
585: printf("Last login: %s\r\n", time_string);
586: else
587: printf("Last login: %s from %s\r\n", time_string, buf);
588: }
589: /*
590: * Print /etc/motd unless a command was specified or printing
591: * it was disabled in server options or login(1) will be
592: * used. Note that some machines appear to print it in
593: * /etc/profile or similar.
594: */
595: if (command == NULL && options.print_motd && !quiet_login &&
596: !options.use_login) {
597: /* Print /etc/motd if it exists. */
598: f = fopen("/etc/motd", "r");
599: if (f) {
600: while (fgets(line, sizeof(line), f))
601: fputs(line, stdout);
602: fclose(f);
603: }
604: }
605: /* Do common processing for the child, such as execing the command. */
1.14 deraadt 606: do_child(command, pw, s->term, s->display, s->auth_proto,
607: s->auth_data, s->tty);
1.1 markus 608: /* NOTREACHED */
609: }
610: if (pid < 0)
611: packet_disconnect("fork failed: %.100s", strerror(errno));
612: s->pid = pid;
613:
614: /* Parent. Close the slave side of the pseudo tty. */
615: close(ttyfd);
616:
617: /*
618: * Create another descriptor of the pty master side for use as the
619: * standard input. We could use the original descriptor, but this
620: * simplifies code in server_loop. The descriptor is bidirectional.
621: */
622: fdout = dup(ptyfd);
623: if (fdout < 0)
624: packet_disconnect("dup #1 failed: %.100s", strerror(errno));
625:
626: /* we keep a reference to the pty master */
627: ptymaster = dup(ptyfd);
628: if (ptymaster < 0)
629: packet_disconnect("dup #2 failed: %.100s", strerror(errno));
630: s->ptymaster = ptymaster;
631:
632: /* Enter interactive session. */
1.2 markus 633: if (compat20) {
634: session_set_fds(s, ptyfd, fdout, -1);
635: } else {
636: server_loop(pid, ptyfd, fdout, -1);
637: /* server_loop _has_ closed ptyfd and fdout. */
638: session_pty_cleanup(s);
639: }
1.1 markus 640: }
641:
642: /*
643: * Sets the value of the given variable in the environment. If the variable
644: * already exists, its value is overriden.
645: */
1.4 markus 646: void
1.1 markus 647: child_set_env(char ***envp, unsigned int *envsizep, const char *name,
648: const char *value)
649: {
650: unsigned int i, namelen;
651: char **env;
652:
653: /*
654: * Find the slot where the value should be stored. If the variable
655: * already exists, we reuse the slot; otherwise we append a new slot
656: * at the end of the array, expanding if necessary.
657: */
658: env = *envp;
659: namelen = strlen(name);
660: for (i = 0; env[i]; i++)
661: if (strncmp(env[i], name, namelen) == 0 && env[i][namelen] == '=')
662: break;
663: if (env[i]) {
664: /* Reuse the slot. */
665: xfree(env[i]);
666: } else {
667: /* New variable. Expand if necessary. */
668: if (i >= (*envsizep) - 1) {
669: (*envsizep) += 50;
670: env = (*envp) = xrealloc(env, (*envsizep) * sizeof(char *));
671: }
672: /* Need to set the NULL pointer at end of array beyond the new slot. */
673: env[i + 1] = NULL;
674: }
675:
676: /* Allocate space and format the variable in the appropriate slot. */
677: env[i] = xmalloc(strlen(name) + 1 + strlen(value) + 1);
678: snprintf(env[i], strlen(name) + 1 + strlen(value) + 1, "%s=%s", name, value);
679: }
680:
681: /*
682: * Reads environment variables from the given file and adds/overrides them
683: * into the environment. If the file does not exist, this does nothing.
684: * Otherwise, it must consist of empty lines, comments (line starts with '#')
685: * and assignments of the form name=value. No other forms are allowed.
686: */
1.4 markus 687: void
1.1 markus 688: read_environment_file(char ***env, unsigned int *envsize,
689: const char *filename)
690: {
691: FILE *f;
692: char buf[4096];
693: char *cp, *value;
694:
695: f = fopen(filename, "r");
696: if (!f)
697: return;
698:
699: while (fgets(buf, sizeof(buf), f)) {
700: for (cp = buf; *cp == ' ' || *cp == '\t'; cp++)
701: ;
702: if (!*cp || *cp == '#' || *cp == '\n')
703: continue;
704: if (strchr(cp, '\n'))
705: *strchr(cp, '\n') = '\0';
706: value = strchr(cp, '=');
707: if (value == NULL) {
708: fprintf(stderr, "Bad line in %.100s: %.200s\n", filename, buf);
709: continue;
710: }
1.14 deraadt 711: /*
712: * Replace the equals sign by nul, and advance value to
713: * the value string.
714: */
1.1 markus 715: *value = '\0';
716: value++;
717: child_set_env(env, envsize, cp, value);
718: }
719: fclose(f);
720: }
721:
722: /*
723: * Performs common processing for the child, such as setting up the
724: * environment, closing extra file descriptors, setting the user and group
725: * ids, and executing the command or shell.
726: */
1.4 markus 727: void
1.1 markus 728: do_child(const char *command, struct passwd * pw, const char *term,
729: const char *display, const char *auth_proto,
730: const char *auth_data, const char *ttyname)
731: {
732: const char *shell, *cp = NULL;
733: char buf[256];
1.16 markus 734: char cmd[1024];
1.1 markus 735: FILE *f;
736: unsigned int envsize, i;
737: char **env;
738: extern char **environ;
739: struct stat st;
740: char *argv[10];
1.17 markus 741:
742: /* login(1) is only called if we execute the login shell */
743: if (options.use_login && command != NULL)
744: options.use_login = 0;
1.1 markus 745:
746: f = fopen("/etc/nologin", "r");
747: if (f) {
748: /* /etc/nologin exists. Print its contents and exit. */
749: while (fgets(buf, sizeof(buf), f))
750: fputs(buf, stderr);
751: fclose(f);
752: if (pw->pw_uid != 0)
753: exit(254);
754: }
755: /* Set login name in the kernel. */
756: if (setlogin(pw->pw_name) < 0)
757: error("setlogin failed: %s", strerror(errno));
758:
759: /* Set uid, gid, and groups. */
760: /* Login(1) does this as well, and it needs uid 0 for the "-h"
761: switch, so we let login(1) to this for us. */
762: if (!options.use_login) {
763: if (getuid() == 0 || geteuid() == 0) {
764: if (setgid(pw->pw_gid) < 0) {
765: perror("setgid");
766: exit(1);
767: }
768: /* Initialize the group list. */
769: if (initgroups(pw->pw_name, pw->pw_gid) < 0) {
770: perror("initgroups");
771: exit(1);
772: }
773: endgrent();
774:
775: /* Permanently switch to the desired uid. */
776: permanently_set_uid(pw->pw_uid);
777: }
778: if (getuid() != pw->pw_uid || geteuid() != pw->pw_uid)
779: fatal("Failed to set uids to %d.", (int) pw->pw_uid);
780: }
781: /*
782: * Get the shell from the password data. An empty shell field is
783: * legal, and means /bin/sh.
784: */
785: shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell;
786:
787: #ifdef AFS
788: /* Try to get AFS tokens for the local cell. */
789: if (k_hasafs()) {
790: char cell[64];
791:
792: if (k_afs_cell_of_file(pw->pw_dir, cell, sizeof(cell)) == 0)
793: krb_afslog(cell, 0);
794:
795: krb_afslog(0, 0);
796: }
797: #endif /* AFS */
798:
799: /* Initialize the environment. */
800: envsize = 100;
801: env = xmalloc(envsize * sizeof(char *));
802: env[0] = NULL;
803:
804: if (!options.use_login) {
805: /* Set basic environment. */
806: child_set_env(&env, &envsize, "USER", pw->pw_name);
807: child_set_env(&env, &envsize, "LOGNAME", pw->pw_name);
808: child_set_env(&env, &envsize, "HOME", pw->pw_dir);
809: child_set_env(&env, &envsize, "PATH", _PATH_STDPATH);
810:
811: snprintf(buf, sizeof buf, "%.200s/%.50s",
812: _PATH_MAILDIR, pw->pw_name);
813: child_set_env(&env, &envsize, "MAIL", buf);
814:
815: /* Normal systems set SHELL by default. */
816: child_set_env(&env, &envsize, "SHELL", shell);
817: }
818: if (getenv("TZ"))
819: child_set_env(&env, &envsize, "TZ", getenv("TZ"));
820:
821: /* Set custom environment options from RSA authentication. */
822: while (custom_environment) {
823: struct envstring *ce = custom_environment;
824: char *s = ce->s;
825: int i;
826: for (i = 0; s[i] != '=' && s[i]; i++);
827: if (s[i] == '=') {
828: s[i] = 0;
829: child_set_env(&env, &envsize, s, s + i + 1);
830: }
831: custom_environment = ce->next;
832: xfree(ce->s);
833: xfree(ce);
834: }
835:
836: snprintf(buf, sizeof buf, "%.50s %d %d",
837: get_remote_ipaddr(), get_remote_port(), get_local_port());
838: child_set_env(&env, &envsize, "SSH_CLIENT", buf);
839:
840: if (ttyname)
841: child_set_env(&env, &envsize, "SSH_TTY", ttyname);
842: if (term)
843: child_set_env(&env, &envsize, "TERM", term);
844: if (display)
845: child_set_env(&env, &envsize, "DISPLAY", display);
846:
847: #ifdef KRB4
848: {
849: extern char *ticket;
850:
851: if (ticket)
852: child_set_env(&env, &envsize, "KRBTKFILE", ticket);
853: }
854: #endif /* KRB4 */
855:
856: if (xauthfile)
857: child_set_env(&env, &envsize, "XAUTHORITY", xauthfile);
858: if (auth_get_socket_name() != NULL)
859: child_set_env(&env, &envsize, SSH_AUTHSOCKET_ENV_NAME,
860: auth_get_socket_name());
861:
862: /* read $HOME/.ssh/environment. */
863: if (!options.use_login) {
1.14 deraadt 864: snprintf(buf, sizeof buf, "%.200s/.ssh/environment",
865: pw->pw_dir);
1.1 markus 866: read_environment_file(&env, &envsize, buf);
867: }
868: if (debug_flag) {
869: /* dump the environment */
870: fprintf(stderr, "Environment:\n");
871: for (i = 0; env[i]; i++)
872: fprintf(stderr, " %.200s\n", env[i]);
873: }
874: /*
875: * Close the connection descriptors; note that this is the child, and
876: * the server will still have the socket open, and it is important
877: * that we do not shutdown it. Note that the descriptors cannot be
878: * closed before building the environment, as we call
879: * get_remote_ipaddr there.
880: */
881: if (packet_get_connection_in() == packet_get_connection_out())
882: close(packet_get_connection_in());
883: else {
884: close(packet_get_connection_in());
885: close(packet_get_connection_out());
886: }
887: /*
888: * Close all descriptors related to channels. They will still remain
889: * open in the parent.
890: */
891: /* XXX better use close-on-exec? -markus */
892: channel_close_all();
893:
894: /*
895: * Close any extra file descriptors. Note that there may still be
896: * descriptors left by system functions. They will be closed later.
897: */
898: endpwent();
899:
900: /*
901: * Close any extra open file descriptors so that we don\'t have them
902: * hanging around in clients. Note that we want to do this after
903: * initgroups, because at least on Solaris 2.3 it leaves file
904: * descriptors open.
905: */
906: for (i = 3; i < 64; i++)
907: close(i);
908:
909: /* Change current directory to the user\'s home directory. */
910: if (chdir(pw->pw_dir) < 0)
911: fprintf(stderr, "Could not chdir to home directory %s: %s\n",
912: pw->pw_dir, strerror(errno));
913:
914: /*
915: * Must take new environment into use so that .ssh/rc, /etc/sshrc and
916: * xauth are run in the proper environment.
917: */
918: environ = env;
919:
920: /*
921: * Run $HOME/.ssh/rc, /etc/sshrc, or xauth (whichever is found first
922: * in this order).
923: */
924: if (!options.use_login) {
925: if (stat(SSH_USER_RC, &st) >= 0) {
926: if (debug_flag)
927: fprintf(stderr, "Running /bin/sh %s\n", SSH_USER_RC);
928:
929: f = popen("/bin/sh " SSH_USER_RC, "w");
930: if (f) {
931: if (auth_proto != NULL && auth_data != NULL)
932: fprintf(f, "%s %s\n", auth_proto, auth_data);
933: pclose(f);
934: } else
935: fprintf(stderr, "Could not run %s\n", SSH_USER_RC);
936: } else if (stat(SSH_SYSTEM_RC, &st) >= 0) {
937: if (debug_flag)
938: fprintf(stderr, "Running /bin/sh %s\n", SSH_SYSTEM_RC);
939:
940: f = popen("/bin/sh " SSH_SYSTEM_RC, "w");
941: if (f) {
942: if (auth_proto != NULL && auth_data != NULL)
943: fprintf(f, "%s %s\n", auth_proto, auth_data);
944: pclose(f);
945: } else
946: fprintf(stderr, "Could not run %s\n", SSH_SYSTEM_RC);
1.16 markus 947: } else if (options.xauth_location != NULL) {
1.1 markus 948: /* Add authority data to .Xauthority if appropriate. */
949: if (auth_proto != NULL && auth_data != NULL) {
1.13 markus 950: char *screen = strchr(display, ':');
951: if (debug_flag) {
1.14 deraadt 952: fprintf(stderr,
953: "Running %.100s add %.100s %.100s %.100s\n",
1.16 markus 954: options.xauth_location, display,
955: auth_proto, auth_data);
1.13 markus 956: if (screen != NULL)
1.14 deraadt 957: fprintf(stderr,
958: "Adding %.*s/unix%s %s %s\n",
959: screen-display, display,
960: screen, auth_proto, auth_data);
1.13 markus 961: }
1.16 markus 962: snprintf(cmd, sizeof cmd, "%s -q -",
963: options.xauth_location);
964: f = popen(cmd, "w");
1.1 markus 965: if (f) {
1.14 deraadt 966: fprintf(f, "add %s %s %s\n", display,
967: auth_proto, auth_data);
1.13 markus 968: if (screen != NULL)
969: fprintf(f, "add %.*s/unix%s %s %s\n",
1.14 deraadt 970: screen-display, display,
971: screen, auth_proto, auth_data);
1.1 markus 972: pclose(f);
1.16 markus 973: } else {
974: fprintf(stderr, "Could not run %s\n",
975: cmd);
976: }
1.1 markus 977: }
978: }
979: /* Get the last component of the shell name. */
980: cp = strrchr(shell, '/');
981: if (cp)
982: cp++;
983: else
984: cp = shell;
985: }
986: /*
987: * If we have no command, execute the shell. In this case, the shell
988: * name to be passed in argv[0] is preceded by '-' to indicate that
989: * this is a login shell.
990: */
991: if (!command) {
992: if (!options.use_login) {
993: char buf[256];
994:
995: /*
996: * Check for mail if we have a tty and it was enabled
997: * in server options.
998: */
999: if (ttyname && options.check_mail) {
1000: char *mailbox;
1001: struct stat mailstat;
1002: mailbox = getenv("MAIL");
1003: if (mailbox != NULL) {
1.14 deraadt 1004: if (stat(mailbox, &mailstat) != 0 ||
1005: mailstat.st_size == 0)
1.1 markus 1006: printf("No mail.\n");
1007: else if (mailstat.st_mtime < mailstat.st_atime)
1008: printf("You have mail.\n");
1009: else
1010: printf("You have new mail.\n");
1011: }
1012: }
1013: /* Start the shell. Set initial character to '-'. */
1014: buf[0] = '-';
1015: strncpy(buf + 1, cp, sizeof(buf) - 1);
1016: buf[sizeof(buf) - 1] = 0;
1017:
1018: /* Execute the shell. */
1019: argv[0] = buf;
1020: argv[1] = NULL;
1021: execve(shell, argv, env);
1022:
1023: /* Executing the shell failed. */
1024: perror(shell);
1025: exit(1);
1026:
1027: } else {
1028: /* Launch login(1). */
1029:
1030: execl("/usr/bin/login", "login", "-h", get_remote_ipaddr(),
1031: "-p", "-f", "--", pw->pw_name, NULL);
1032:
1033: /* Login couldn't be executed, die. */
1034:
1035: perror("login");
1036: exit(1);
1037: }
1038: }
1039: /*
1040: * Execute the command using the user's shell. This uses the -c
1041: * option to execute the command.
1042: */
1043: argv[0] = (char *) cp;
1044: argv[1] = "-c";
1045: argv[2] = (char *) command;
1046: argv[3] = NULL;
1047: execve(shell, argv, env);
1048: perror(shell);
1049: exit(1);
1050: }
1051:
1052: Session *
1053: session_new(void)
1054: {
1055: int i;
1056: static int did_init = 0;
1057: if (!did_init) {
1058: debug("session_new: init");
1059: for(i = 0; i < MAX_SESSIONS; i++) {
1060: sessions[i].used = 0;
1061: sessions[i].self = i;
1062: }
1063: did_init = 1;
1064: }
1065: for(i = 0; i < MAX_SESSIONS; i++) {
1066: Session *s = &sessions[i];
1067: if (! s->used) {
1068: s->pid = 0;
1.7 markus 1069: s->extended = 0;
1.1 markus 1070: s->chanid = -1;
1071: s->ptyfd = -1;
1072: s->ttyfd = -1;
1073: s->term = NULL;
1074: s->pw = NULL;
1075: s->display = NULL;
1076: s->screen = 0;
1077: s->auth_data = NULL;
1078: s->auth_proto = NULL;
1079: s->used = 1;
1.7 markus 1080: s->pw = NULL;
1.1 markus 1081: debug("session_new: session %d", i);
1082: return s;
1083: }
1084: }
1085: return NULL;
1086: }
1087:
1088: void
1089: session_dump(void)
1090: {
1091: int i;
1092: for(i = 0; i < MAX_SESSIONS; i++) {
1093: Session *s = &sessions[i];
1094: debug("dump: used %d session %d %p channel %d pid %d",
1095: s->used,
1096: s->self,
1097: s,
1098: s->chanid,
1099: s->pid);
1100: }
1101: }
1102:
1.2 markus 1103: int
1104: session_open(int chanid)
1105: {
1106: Session *s = session_new();
1107: debug("session_open: channel %d", chanid);
1108: if (s == NULL) {
1109: error("no more sessions");
1110: return 0;
1111: }
1.7 markus 1112: s->pw = auth_get_user();
1113: if (s->pw == NULL)
1114: fatal("no user for session %i", s->self);
1.2 markus 1115: debug("session_open: session %d: link with channel %d", s->self, chanid);
1116: s->chanid = chanid;
1117: return 1;
1118: }
1119:
1120: Session *
1121: session_by_channel(int id)
1122: {
1123: int i;
1124: for(i = 0; i < MAX_SESSIONS; i++) {
1125: Session *s = &sessions[i];
1126: if (s->used && s->chanid == id) {
1127: debug("session_by_channel: session %d channel %d", i, id);
1128: return s;
1129: }
1130: }
1131: debug("session_by_channel: unknown channel %d", id);
1132: session_dump();
1133: return NULL;
1134: }
1135:
1136: Session *
1137: session_by_pid(pid_t pid)
1138: {
1139: int i;
1140: debug("session_by_pid: pid %d", pid);
1141: for(i = 0; i < MAX_SESSIONS; i++) {
1142: Session *s = &sessions[i];
1143: if (s->used && s->pid == pid)
1144: return s;
1145: }
1146: error("session_by_pid: unknown pid %d", pid);
1147: session_dump();
1148: return NULL;
1149: }
1150:
1151: int
1152: session_window_change_req(Session *s)
1153: {
1154: s->col = packet_get_int();
1155: s->row = packet_get_int();
1156: s->xpixel = packet_get_int();
1157: s->ypixel = packet_get_int();
1.3 markus 1158: packet_done();
1.2 markus 1159: pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
1160: return 1;
1161: }
1162:
1163: int
1164: session_pty_req(Session *s)
1165: {
1166: unsigned int len;
1.3 markus 1167: char *term_modes; /* encoded terminal modes */
1.2 markus 1168:
1.19 markus 1169: if (no_pty_flag)
1170: return 0;
1.2 markus 1171: if (s->ttyfd != -1)
1.3 markus 1172: return 0;
1.2 markus 1173: s->term = packet_get_string(&len);
1174: s->col = packet_get_int();
1175: s->row = packet_get_int();
1176: s->xpixel = packet_get_int();
1177: s->ypixel = packet_get_int();
1.3 markus 1178: term_modes = packet_get_string(&len);
1179: packet_done();
1.2 markus 1180:
1181: if (strcmp(s->term, "") == 0) {
1182: xfree(s->term);
1183: s->term = NULL;
1184: }
1185: /* Allocate a pty and open it. */
1186: if (!pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty))) {
1187: xfree(s->term);
1188: s->term = NULL;
1189: s->ptyfd = -1;
1190: s->ttyfd = -1;
1191: error("session_pty_req: session %d alloc failed", s->self);
1.3 markus 1192: xfree(term_modes);
1193: return 0;
1.2 markus 1194: }
1195: debug("session_pty_req: session %d alloc %s", s->self, s->tty);
1196: /*
1197: * Add a cleanup function to clear the utmp entry and record logout
1198: * time in case we call fatal() (e.g., the connection gets closed).
1199: */
1200: fatal_add_cleanup(pty_cleanup_proc, (void *)s);
1201: pty_setowner(s->pw, s->tty);
1202: /* Get window size from the packet. */
1203: pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
1204:
1.9 markus 1205: session_proctitle(s);
1206:
1.3 markus 1207: /* XXX parse and set terminal modes */
1208: xfree(term_modes);
1.2 markus 1209: return 1;
1210: }
1211:
1.7 markus 1212: int
1213: session_subsystem_req(Session *s)
1214: {
1215: unsigned int len;
1216: int success = 0;
1217: char *subsys = packet_get_string(&len);
1.18 jakob 1218: int i;
1.7 markus 1219:
1220: packet_done();
1221: log("subsystem request for %s", subsys);
1.18 jakob 1222:
1223: for (i = 0; i < options.num_subsystems; i++) {
1224: if(strcmp(subsys, options.subsystem_name[i]) == 0) {
1225: debug("subsystem: exec() %s", options.subsystem_command[i]);
1226: do_exec_no_pty(s, options.subsystem_command[i], s->pw);
1227: success = 1;
1228: }
1229: }
1230:
1231: if (!success)
1232: log("subsystem request for %s failed, subsystem not found", subsys);
1.7 markus 1233:
1234: xfree(subsys);
1235: return success;
1236: }
1237:
1238: int
1239: session_x11_req(Session *s)
1240: {
1.22 ! deraadt 1241: if (no_x11_forwarding_flag) {
1.19 markus 1242: debug("X11 forwarding disabled in user configuration file.");
1243: return 0;
1244: }
1.7 markus 1245: if (!options.x11_forwarding) {
1246: debug("X11 forwarding disabled in server configuration file.");
1247: return 0;
1248: }
1249: if (xauthfile != NULL) {
1250: debug("X11 fwd already started.");
1251: return 0;
1252: }
1253:
1254: debug("Received request for X11 forwarding with auth spoofing.");
1255: if (s->display != NULL)
1256: packet_disconnect("Protocol error: X11 display already set.");
1257:
1258: s->single_connection = packet_get_char();
1259: s->auth_proto = packet_get_string(NULL);
1260: s->auth_data = packet_get_string(NULL);
1261: s->screen = packet_get_int();
1262: packet_done();
1263:
1264: s->display = x11_create_display_inet(s->screen, options.x11_display_offset);
1265: if (s->display == NULL) {
1266: xfree(s->auth_proto);
1267: xfree(s->auth_data);
1268: return 0;
1269: }
1270: xauthfile = xmalloc(MAXPATHLEN);
1271: strlcpy(xauthfile, "/tmp/ssh-XXXXXXXX", MAXPATHLEN);
1272: temporarily_use_uid(s->pw->pw_uid);
1273: if (mkdtemp(xauthfile) == NULL) {
1274: restore_uid();
1275: error("private X11 dir: mkdtemp %s failed: %s",
1276: xauthfile, strerror(errno));
1277: xfree(xauthfile);
1278: xauthfile = NULL;
1279: xfree(s->auth_proto);
1280: xfree(s->auth_data);
1281: /* XXXX remove listening channels */
1282: return 0;
1283: }
1284: strlcat(xauthfile, "/cookies", MAXPATHLEN);
1285: open(xauthfile, O_RDWR|O_CREAT|O_EXCL, 0600);
1286: restore_uid();
1287: fatal_add_cleanup(xauthfile_cleanup_proc, s);
1288: return 1;
1289: }
1290:
1.19 markus 1291: int
1292: session_shell_req(Session *s)
1293: {
1294: /* if forced_command == NULL, the shell is execed */
1295: char *shell = forced_command;
1296: packet_done();
1297: s->extended = 1;
1298: if (s->ttyfd == -1)
1299: do_exec_no_pty(s, shell, s->pw);
1300: else
1301: do_exec_pty(s, shell, s->pw);
1302: return 1;
1303: }
1304:
1305: int
1306: session_exec_req(Session *s)
1307: {
1.20 markus 1308: unsigned int len;
1.19 markus 1309: char *command = packet_get_string(&len);
1310: packet_done();
1311: if (forced_command) {
1312: xfree(command);
1313: command = forced_command;
1314: debug("Forced command '%.500s'", forced_command);
1315: }
1316: s->extended = 1;
1317: if (s->ttyfd == -1)
1318: do_exec_no_pty(s, command, s->pw);
1319: else
1320: do_exec_pty(s, command, s->pw);
1321: if (forced_command == NULL)
1322: xfree(command);
1323: return 1;
1324: }
1325:
1.2 markus 1326: void
1327: session_input_channel_req(int id, void *arg)
1328: {
1329: unsigned int len;
1330: int reply;
1331: int success = 0;
1332: char *rtype;
1333: Session *s;
1334: Channel *c;
1335:
1336: rtype = packet_get_string(&len);
1337: reply = packet_get_char();
1338:
1339: s = session_by_channel(id);
1340: if (s == NULL)
1341: fatal("session_input_channel_req: channel %d: no session", id);
1342: c = channel_lookup(id);
1343: if (c == NULL)
1344: fatal("session_input_channel_req: channel %d: bad channel", id);
1345:
1346: debug("session_input_channel_req: session %d channel %d request %s reply %d",
1347: s->self, id, rtype, reply);
1348:
1349: /*
1350: * a session is in LARVAL state until a shell
1351: * or programm is executed
1352: */
1353: if (c->type == SSH_CHANNEL_LARVAL) {
1354: if (strcmp(rtype, "shell") == 0) {
1.19 markus 1355: success = session_shell_req(s);
1.2 markus 1356: } else if (strcmp(rtype, "exec") == 0) {
1.19 markus 1357: success = session_exec_req(s);
1.2 markus 1358: } else if (strcmp(rtype, "pty-req") == 0) {
1.3 markus 1359: success = session_pty_req(s);
1.7 markus 1360: } else if (strcmp(rtype, "x11-req") == 0) {
1361: success = session_x11_req(s);
1362: } else if (strcmp(rtype, "subsystem") == 0) {
1363: success = session_subsystem_req(s);
1.2 markus 1364: }
1365: }
1366: if (strcmp(rtype, "window-change") == 0) {
1367: success = session_window_change_req(s);
1368: }
1369:
1370: if (reply) {
1371: packet_start(success ?
1372: SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
1373: packet_put_int(c->remote_id);
1374: packet_send();
1375: }
1376: xfree(rtype);
1377: }
1378:
1379: void
1380: session_set_fds(Session *s, int fdin, int fdout, int fderr)
1381: {
1382: if (!compat20)
1383: fatal("session_set_fds: called for proto != 2.0");
1384: /*
1385: * now that have a child and a pipe to the child,
1386: * we can activate our channel and register the fd's
1387: */
1388: if (s->chanid == -1)
1389: fatal("no channel for session %d", s->self);
1390: channel_set_fds(s->chanid,
1391: fdout, fdin, fderr,
1392: fderr == -1 ? CHAN_EXTENDED_IGNORE : CHAN_EXTENDED_READ);
1393: }
1394:
1.1 markus 1395: void
1396: session_pty_cleanup(Session *s)
1397: {
1398: if (s == NULL || s->ttyfd == -1)
1399: return;
1400:
1401: debug("session_pty_cleanup: session %i release %s", s->self, s->tty);
1402:
1403: /* Cancel the cleanup function. */
1404: fatal_remove_cleanup(pty_cleanup_proc, (void *)s);
1405:
1406: /* Record that the user has logged out. */
1407: record_logout(s->pid, s->tty);
1408:
1409: /* Release the pseudo-tty. */
1410: pty_release(s->tty);
1411:
1412: /*
1413: * Close the server side of the socket pairs. We must do this after
1414: * the pty cleanup, so that another process doesn't get this pty
1415: * while we're still cleaning up.
1416: */
1417: if (close(s->ptymaster) < 0)
1418: error("close(s->ptymaster): %s", strerror(errno));
1.2 markus 1419: }
1420:
1421: void
1422: session_exit_message(Session *s, int status)
1423: {
1424: Channel *c;
1425: if (s == NULL)
1426: fatal("session_close: no session");
1427: c = channel_lookup(s->chanid);
1428: if (c == NULL)
1429: fatal("session_close: session %d: no channel %d",
1430: s->self, s->chanid);
1431: debug("session_exit_message: session %d channel %d pid %d",
1432: s->self, s->chanid, s->pid);
1433:
1434: if (WIFEXITED(status)) {
1435: channel_request_start(s->chanid,
1436: "exit-status", 0);
1437: packet_put_int(WEXITSTATUS(status));
1438: packet_send();
1439: } else if (WIFSIGNALED(status)) {
1440: channel_request_start(s->chanid,
1441: "exit-signal", 0);
1442: packet_put_int(WTERMSIG(status));
1443: packet_put_char(WCOREDUMP(status));
1444: packet_put_cstring("");
1445: packet_put_cstring("");
1446: packet_send();
1447: } else {
1448: /* Some weird exit cause. Just exit. */
1449: packet_disconnect("wait returned status %04x.", status);
1450: }
1451:
1452: /* disconnect channel */
1453: debug("session_exit_message: release channel %d", s->chanid);
1454: channel_cancel_cleanup(s->chanid);
1.5 markus 1455: /*
1456: * emulate a write failure with 'chan_write_failed', nobody will be
1457: * interested in data we write.
1458: * Note that we must not call 'chan_read_failed', since there could
1459: * be some more data waiting in the pipe.
1460: */
1.8 markus 1461: if (c->ostate != CHAN_OUTPUT_CLOSED)
1462: chan_write_failed(c);
1.2 markus 1463: s->chanid = -1;
1464: }
1465:
1466: void
1467: session_free(Session *s)
1468: {
1469: debug("session_free: session %d pid %d", s->self, s->pid);
1470: if (s->term)
1471: xfree(s->term);
1472: if (s->display)
1473: xfree(s->display);
1474: if (s->auth_data)
1475: xfree(s->auth_data);
1476: if (s->auth_proto)
1477: xfree(s->auth_proto);
1478: s->used = 0;
1479: }
1480:
1481: void
1482: session_close(Session *s)
1483: {
1484: session_pty_cleanup(s);
1485: session_free(s);
1.9 markus 1486: session_proctitle(s);
1.2 markus 1487: }
1488:
1489: void
1490: session_close_by_pid(pid_t pid, int status)
1491: {
1492: Session *s = session_by_pid(pid);
1493: if (s == NULL) {
1494: debug("session_close_by_pid: no session for pid %d", s->pid);
1495: return;
1496: }
1497: if (s->chanid != -1)
1498: session_exit_message(s, status);
1499: session_close(s);
1500: }
1501:
1502: /*
1503: * this is called when a channel dies before
1504: * the session 'child' itself dies
1505: */
1506: void
1507: session_close_by_channel(int id, void *arg)
1508: {
1509: Session *s = session_by_channel(id);
1510: if (s == NULL) {
1511: debug("session_close_by_channel: no session for channel %d", id);
1512: return;
1513: }
1514: /* disconnect channel */
1515: channel_cancel_cleanup(s->chanid);
1516: s->chanid = -1;
1517:
1518: debug("session_close_by_channel: channel %d kill %d", id, s->pid);
1519: if (s->pid == 0) {
1520: /* close session immediately */
1521: session_close(s);
1522: } else {
1523: /* notify child, delay session cleanup */
1524: if (kill(s->pid, (s->ttyfd == -1) ? SIGTERM : SIGHUP) < 0)
1525: error("session_close_by_channel: kill %d: %s",
1526: s->pid, strerror(errno));
1527: }
1.9 markus 1528: }
1529:
1530: char *
1531: session_tty_list(void)
1532: {
1533: static char buf[1024];
1534: int i;
1535: buf[0] = '\0';
1536: for(i = 0; i < MAX_SESSIONS; i++) {
1537: Session *s = &sessions[i];
1538: if (s->used && s->ttyfd != -1) {
1539: if (buf[0] != '\0')
1540: strlcat(buf, ",", sizeof buf);
1541: strlcat(buf, strrchr(s->tty, '/') + 1, sizeof buf);
1542: }
1543: }
1544: if (buf[0] == '\0')
1545: strlcpy(buf, "notty", sizeof buf);
1546: return buf;
1547: }
1548:
1549: void
1550: session_proctitle(Session *s)
1551: {
1552: if (s->pw == NULL)
1553: error("no user for session %d", s->self);
1554: else
1555: setproctitle("%s@%s", s->pw->pw_name, session_tty_list());
1.2 markus 1556: }
1557:
1558: void
1559: do_authenticated2(void)
1560: {
1561: /*
1562: * Cancel the alarm we set to limit the time taken for
1563: * authentication.
1564: */
1565: alarm(0);
1.21 markus 1566: close(startup_pipe);
1.2 markus 1567: server_loop2();
1.7 markus 1568: if (xauthfile)
1569: xauthfile_cleanup_proc(NULL);
1.1 markus 1570: }
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