Annotation of src/usr.bin/ssh/session.c, Revision 1.24
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"
1.24 ! markus 11: RCSID("$OpenBSD: session.c,v 1.23 2000/07/11 08:11:33 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);
1.24 ! markus 64: void do_login(Session *s);
1.1 markus 65:
66: void
67: do_child(const char *command, struct passwd * pw, const char *term,
68: const char *display, const char *auth_proto,
69: const char *auth_data, const char *ttyname);
70:
71: /* import */
72: extern ServerOptions options;
73: extern char *__progname;
74: extern int log_stderr;
75: extern int debug_flag;
76:
1.21 markus 77: extern int startup_pipe;
78:
1.1 markus 79: /* Local Xauthority file. */
80: static char *xauthfile;
81:
82: /* data */
83: #define MAX_SESSIONS 10
84: Session sessions[MAX_SESSIONS];
85:
86: /*
87: * Remove local Xauthority file.
88: */
89: void
90: xauthfile_cleanup_proc(void *ignore)
91: {
92: debug("xauthfile_cleanup_proc called");
93:
94: if (xauthfile != NULL) {
95: char *p;
96: unlink(xauthfile);
97: p = strrchr(xauthfile, '/');
98: if (p != NULL) {
99: *p = '\0';
100: rmdir(xauthfile);
101: }
102: xfree(xauthfile);
103: xauthfile = NULL;
104: }
105: }
106:
107: /*
108: * Function to perform cleanup if we get aborted abnormally (e.g., due to a
109: * dropped connection).
110: */
1.4 markus 111: void
1.1 markus 112: pty_cleanup_proc(void *session)
113: {
114: Session *s=session;
115: if (s == NULL)
116: fatal("pty_cleanup_proc: no session");
117: debug("pty_cleanup_proc: %s", s->tty);
118:
119: if (s->pid != 0) {
120: /* Record that the user has logged out. */
121: record_logout(s->pid, s->tty);
122: }
123:
124: /* Release the pseudo-tty. */
125: pty_release(s->tty);
126: }
127:
128: /*
129: * Prepares for an interactive session. This is called after the user has
130: * been successfully authenticated. During this message exchange, pseudo
131: * terminals are allocated, X11, TCP/IP, and authentication agent forwardings
132: * are requested, etc.
133: */
1.4 markus 134: void
1.1 markus 135: do_authenticated(struct passwd * pw)
136: {
137: Session *s;
138: int type;
139: int compression_level = 0, enable_compression_after_reply = 0;
140: int have_pty = 0;
141: char *command;
142: int n_bytes;
143: int plen;
144: unsigned int proto_len, data_len, dlen;
145:
146: /*
147: * Cancel the alarm we set to limit the time taken for
148: * authentication.
149: */
150: alarm(0);
1.23 deraadt 151: if (startup_pipe != -1) {
152: close(startup_pipe);
153: startup_pipe = -1;
154: }
1.1 markus 155:
156: /*
157: * Inform the channel mechanism that we are the server side and that
158: * the client may request to connect to any port at all. (The user
159: * could do it anyway, and we wouldn\'t know what is permitted except
160: * by the client telling us, so we can equally well trust the client
161: * not to request anything bogus.)
162: */
163: if (!no_port_forwarding_flag)
164: channel_permit_all_opens();
165:
166: s = session_new();
1.7 markus 167: s->pw = pw;
1.1 markus 168:
169: /*
170: * We stay in this loop until the client requests to execute a shell
171: * or a command.
172: */
173: for (;;) {
174: int success = 0;
175:
176: /* Get a packet from the client. */
177: type = packet_read(&plen);
178:
179: /* Process the packet. */
180: switch (type) {
181: case SSH_CMSG_REQUEST_COMPRESSION:
182: packet_integrity_check(plen, 4, type);
183: compression_level = packet_get_int();
184: if (compression_level < 1 || compression_level > 9) {
185: packet_send_debug("Received illegal compression level %d.",
186: compression_level);
187: break;
188: }
189: /* Enable compression after we have responded with SUCCESS. */
190: enable_compression_after_reply = 1;
191: success = 1;
192: break;
193:
194: case SSH_CMSG_REQUEST_PTY:
195: if (no_pty_flag) {
196: debug("Allocating a pty not permitted for this authentication.");
197: break;
198: }
199: if (have_pty)
200: packet_disconnect("Protocol error: you already have a pty.");
201:
202: debug("Allocating pty.");
203:
204: /* Allocate a pty and open it. */
205: if (!pty_allocate(&s->ptyfd, &s->ttyfd, s->tty,
206: sizeof(s->tty))) {
207: error("Failed to allocate pty.");
208: break;
209: }
210: fatal_add_cleanup(pty_cleanup_proc, (void *)s);
211: pty_setowner(pw, s->tty);
212:
213: /* Get TERM from the packet. Note that the value may be of arbitrary length. */
214: s->term = packet_get_string(&dlen);
215: packet_integrity_check(dlen, strlen(s->term), type);
216: /* packet_integrity_check(plen, 4 + dlen + 4*4 + n_bytes, type); */
217: /* Remaining bytes */
218: n_bytes = plen - (4 + dlen + 4 * 4);
219:
220: if (strcmp(s->term, "") == 0) {
221: xfree(s->term);
222: s->term = NULL;
223: }
224: /* Get window size from the packet. */
225: s->row = packet_get_int();
226: s->col = packet_get_int();
227: s->xpixel = packet_get_int();
228: s->ypixel = packet_get_int();
229: pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
230:
231: /* Get tty modes from the packet. */
232: tty_parse_modes(s->ttyfd, &n_bytes);
233: packet_integrity_check(plen, 4 + dlen + 4 * 4 + n_bytes, type);
1.10 markus 234:
235: session_proctitle(s);
1.1 markus 236:
237: /* Indicate that we now have a pty. */
238: success = 1;
239: have_pty = 1;
240: break;
241:
242: case SSH_CMSG_X11_REQUEST_FORWARDING:
243: if (!options.x11_forwarding) {
244: packet_send_debug("X11 forwarding disabled in server configuration file.");
245: break;
246: }
1.16 markus 247: if (!options.xauth_location) {
248: packet_send_debug("No xauth program; cannot forward with spoofing.");
249: break;
250: }
1.1 markus 251: if (no_x11_forwarding_flag) {
252: packet_send_debug("X11 forwarding not permitted for this authentication.");
253: break;
254: }
255: debug("Received request for X11 forwarding with auth spoofing.");
256: if (s->display != NULL)
257: packet_disconnect("Protocol error: X11 display already set.");
258:
259: s->auth_proto = packet_get_string(&proto_len);
260: s->auth_data = packet_get_string(&data_len);
261: packet_integrity_check(plen, 4 + proto_len + 4 + data_len + 4, type);
262:
263: if (packet_get_protocol_flags() & SSH_PROTOFLAG_SCREEN_NUMBER)
264: s->screen = packet_get_int();
265: else
266: s->screen = 0;
267: s->display = x11_create_display_inet(s->screen, options.x11_display_offset);
268:
269: if (s->display == NULL)
270: break;
271:
272: /* Setup to always have a local .Xauthority. */
273: xauthfile = xmalloc(MAXPATHLEN);
274: strlcpy(xauthfile, "/tmp/ssh-XXXXXXXX", MAXPATHLEN);
275: temporarily_use_uid(pw->pw_uid);
276: if (mkdtemp(xauthfile) == NULL) {
277: restore_uid();
278: error("private X11 dir: mkdtemp %s failed: %s",
279: xauthfile, strerror(errno));
280: xfree(xauthfile);
281: xauthfile = NULL;
1.7 markus 282: /* XXXX remove listening channels */
1.1 markus 283: break;
284: }
285: strlcat(xauthfile, "/cookies", MAXPATHLEN);
286: open(xauthfile, O_RDWR|O_CREAT|O_EXCL, 0600);
287: restore_uid();
288: fatal_add_cleanup(xauthfile_cleanup_proc, NULL);
289: success = 1;
290: break;
291:
292: case SSH_CMSG_AGENT_REQUEST_FORWARDING:
293: if (no_agent_forwarding_flag || compat13) {
294: debug("Authentication agent forwarding not permitted for this authentication.");
295: break;
296: }
297: debug("Received authentication agent forwarding request.");
1.15 markus 298: success = auth_input_request_forwarding(pw);
1.1 markus 299: break;
300:
301: case SSH_CMSG_PORT_FORWARD_REQUEST:
302: if (no_port_forwarding_flag) {
303: debug("Port forwarding not permitted for this authentication.");
304: break;
305: }
306: debug("Received TCP/IP port forwarding request.");
1.12 markus 307: channel_input_port_forward_request(pw->pw_uid == 0, options.gateway_ports);
1.1 markus 308: success = 1;
309: break;
310:
311: case SSH_CMSG_MAX_PACKET_SIZE:
312: if (packet_set_maxsize(packet_get_int()) > 0)
313: success = 1;
314: break;
315:
316: case SSH_CMSG_EXEC_SHELL:
317: case SSH_CMSG_EXEC_CMD:
318: /* Set interactive/non-interactive mode. */
319: packet_set_interactive(have_pty || s->display != NULL,
320: options.keepalives);
321:
322: if (type == SSH_CMSG_EXEC_CMD) {
323: command = packet_get_string(&dlen);
324: debug("Exec command '%.500s'", command);
325: packet_integrity_check(plen, 4 + dlen, type);
326: } else {
327: command = NULL;
328: packet_integrity_check(plen, 0, type);
329: }
330: if (forced_command != NULL) {
331: command = forced_command;
332: debug("Forced command '%.500s'", forced_command);
333: }
334: if (have_pty)
335: do_exec_pty(s, command, pw);
336: else
337: do_exec_no_pty(s, command, pw);
338:
339: if (command != NULL)
340: xfree(command);
341: /* Cleanup user's local Xauthority file. */
342: if (xauthfile)
343: xauthfile_cleanup_proc(NULL);
344: return;
345:
346: default:
347: /*
348: * Any unknown messages in this phase are ignored,
349: * and a failure message is returned.
350: */
351: log("Unknown packet type received after authentication: %d", type);
352: }
353: packet_start(success ? SSH_SMSG_SUCCESS : SSH_SMSG_FAILURE);
354: packet_send();
355: packet_write_wait();
356:
357: /* Enable compression now that we have replied if appropriate. */
358: if (enable_compression_after_reply) {
359: enable_compression_after_reply = 0;
360: packet_start_compression(compression_level);
361: }
362: }
363: }
364:
365: /*
366: * This is called to fork and execute a command when we have no tty. This
367: * will call do_child from the child, and server_loop from the parent after
368: * setting up file descriptors and such.
369: */
1.4 markus 370: void
1.1 markus 371: do_exec_no_pty(Session *s, const char *command, struct passwd * pw)
372: {
373: int pid;
374:
375: #ifdef USE_PIPES
376: int pin[2], pout[2], perr[2];
377: /* Allocate pipes for communicating with the program. */
378: if (pipe(pin) < 0 || pipe(pout) < 0 || pipe(perr) < 0)
379: packet_disconnect("Could not create pipes: %.100s",
380: strerror(errno));
381: #else /* USE_PIPES */
382: int inout[2], err[2];
383: /* Uses socket pairs to communicate with the program. */
384: if (socketpair(AF_UNIX, SOCK_STREAM, 0, inout) < 0 ||
385: socketpair(AF_UNIX, SOCK_STREAM, 0, err) < 0)
386: packet_disconnect("Could not create socket pairs: %.100s",
387: strerror(errno));
388: #endif /* USE_PIPES */
389: if (s == NULL)
390: fatal("do_exec_no_pty: no session");
391:
1.9 markus 392: session_proctitle(s);
1.1 markus 393:
394: /* Fork the child. */
395: if ((pid = fork()) == 0) {
396: /* Child. Reinitialize the log since the pid has changed. */
397: log_init(__progname, options.log_level, options.log_facility, log_stderr);
398:
399: /*
400: * Create a new session and process group since the 4.4BSD
401: * setlogin() affects the entire process group.
402: */
403: if (setsid() < 0)
404: error("setsid failed: %.100s", strerror(errno));
405:
406: #ifdef USE_PIPES
407: /*
408: * Redirect stdin. We close the parent side of the socket
409: * pair, and make the child side the standard input.
410: */
411: close(pin[1]);
412: if (dup2(pin[0], 0) < 0)
413: perror("dup2 stdin");
414: close(pin[0]);
415:
416: /* Redirect stdout. */
417: close(pout[0]);
418: if (dup2(pout[1], 1) < 0)
419: perror("dup2 stdout");
420: close(pout[1]);
421:
422: /* Redirect stderr. */
423: close(perr[0]);
424: if (dup2(perr[1], 2) < 0)
425: perror("dup2 stderr");
426: close(perr[1]);
427: #else /* USE_PIPES */
428: /*
429: * Redirect stdin, stdout, and stderr. Stdin and stdout will
430: * use the same socket, as some programs (particularly rdist)
431: * seem to depend on it.
432: */
433: close(inout[1]);
434: close(err[1]);
435: if (dup2(inout[0], 0) < 0) /* stdin */
436: perror("dup2 stdin");
437: if (dup2(inout[0], 1) < 0) /* stdout. Note: same socket as stdin. */
438: perror("dup2 stdout");
439: if (dup2(err[0], 2) < 0) /* stderr */
440: perror("dup2 stderr");
441: #endif /* USE_PIPES */
442:
443: /* Do processing for the child (exec command etc). */
444: do_child(command, pw, NULL, s->display, s->auth_proto, s->auth_data, NULL);
445: /* NOTREACHED */
446: }
447: if (pid < 0)
448: packet_disconnect("fork failed: %.100s", strerror(errno));
449: s->pid = pid;
450: #ifdef USE_PIPES
451: /* We are the parent. Close the child sides of the pipes. */
452: close(pin[0]);
453: close(pout[1]);
454: close(perr[1]);
455:
1.2 markus 456: if (compat20) {
1.7 markus 457: session_set_fds(s, pin[1], pout[0], s->extended ? perr[0] : -1);
1.2 markus 458: } else {
459: /* Enter the interactive session. */
460: server_loop(pid, pin[1], pout[0], perr[0]);
461: /* server_loop has closed pin[1], pout[1], and perr[1]. */
462: }
1.1 markus 463: #else /* USE_PIPES */
464: /* We are the parent. Close the child sides of the socket pairs. */
465: close(inout[0]);
466: close(err[0]);
467:
468: /*
469: * Enter the interactive session. Note: server_loop must be able to
470: * handle the case that fdin and fdout are the same.
471: */
1.2 markus 472: if (compat20) {
1.7 markus 473: session_set_fds(s, inout[1], inout[1], s->extended ? err[1] : -1);
1.2 markus 474: } else {
475: server_loop(pid, inout[1], inout[1], err[1]);
476: /* server_loop has closed inout[1] and err[1]. */
477: }
1.1 markus 478: #endif /* USE_PIPES */
479: }
480:
481: /*
482: * This is called to fork and execute a command when we have a tty. This
483: * will call do_child from the child, and server_loop from the parent after
484: * setting up file descriptors, controlling tty, updating wtmp, utmp,
485: * lastlog, and other such operations.
486: */
1.4 markus 487: void
1.1 markus 488: do_exec_pty(Session *s, const char *command, struct passwd * pw)
489: {
490: int fdout, ptyfd, ttyfd, ptymaster;
491: pid_t pid;
492:
493: if (s == NULL)
494: fatal("do_exec_pty: no session");
495: ptyfd = s->ptyfd;
496: ttyfd = s->ttyfd;
497:
498: /* Fork the child. */
499: if ((pid = fork()) == 0) {
1.24 ! markus 500: /* Child. Reinitialize the log because the pid has changed. */
1.1 markus 501: log_init(__progname, options.log_level, options.log_facility, log_stderr);
502:
503: /* Close the master side of the pseudo tty. */
504: close(ptyfd);
505:
506: /* Make the pseudo tty our controlling tty. */
507: pty_make_controlling_tty(&ttyfd, s->tty);
508:
509: /* Redirect stdin from the pseudo tty. */
510: if (dup2(ttyfd, fileno(stdin)) < 0)
511: error("dup2 stdin failed: %.100s", strerror(errno));
512:
513: /* Redirect stdout to the pseudo tty. */
514: if (dup2(ttyfd, fileno(stdout)) < 0)
515: error("dup2 stdin failed: %.100s", strerror(errno));
516:
517: /* Redirect stderr to the pseudo tty. */
518: if (dup2(ttyfd, fileno(stderr)) < 0)
519: error("dup2 stdin failed: %.100s", strerror(errno));
520:
521: /* Close the extra descriptor for the pseudo tty. */
522: close(ttyfd);
523:
1.24 ! markus 524: /* record login, etc. similar to login(1) */
! 525: if (command == NULL && !options.use_login)
! 526: do_login(s);
1.1 markus 527:
528: /* Do common processing for the child, such as execing the command. */
1.14 deraadt 529: do_child(command, pw, s->term, s->display, s->auth_proto,
530: s->auth_data, s->tty);
1.1 markus 531: /* NOTREACHED */
532: }
533: if (pid < 0)
534: packet_disconnect("fork failed: %.100s", strerror(errno));
535: s->pid = pid;
536:
537: /* Parent. Close the slave side of the pseudo tty. */
538: close(ttyfd);
539:
540: /*
541: * Create another descriptor of the pty master side for use as the
542: * standard input. We could use the original descriptor, but this
543: * simplifies code in server_loop. The descriptor is bidirectional.
544: */
545: fdout = dup(ptyfd);
546: if (fdout < 0)
547: packet_disconnect("dup #1 failed: %.100s", strerror(errno));
548:
549: /* we keep a reference to the pty master */
550: ptymaster = dup(ptyfd);
551: if (ptymaster < 0)
552: packet_disconnect("dup #2 failed: %.100s", strerror(errno));
553: s->ptymaster = ptymaster;
554:
555: /* Enter interactive session. */
1.2 markus 556: if (compat20) {
557: session_set_fds(s, ptyfd, fdout, -1);
558: } else {
559: server_loop(pid, ptyfd, fdout, -1);
560: /* server_loop _has_ closed ptyfd and fdout. */
561: session_pty_cleanup(s);
1.24 ! markus 562: }
! 563: }
! 564:
! 565: /* administrative, login(1)-like work */
! 566: void
! 567: do_login(Session *s)
! 568: {
! 569: FILE *f;
! 570: char *time_string;
! 571: char buf[256];
! 572: socklen_t fromlen;
! 573: struct sockaddr_storage from;
! 574: struct stat st;
! 575: time_t last_login_time;
! 576: struct passwd * pw = s->pw;
! 577: pid_t pid = getpid();
! 578:
! 579: /*
! 580: * Get IP address of client. If the connection is not a socket, let
! 581: * the address be 0.0.0.0.
! 582: */
! 583: memset(&from, 0, sizeof(from));
! 584: if (packet_connection_is_on_socket()) {
! 585: fromlen = sizeof(from);
! 586: if (getpeername(packet_get_connection_in(),
! 587: (struct sockaddr *) & from, &fromlen) < 0) {
! 588: debug("getpeername: %.100s", strerror(errno));
! 589: fatal_cleanup();
! 590: }
! 591: }
! 592: /* Record that there was a login on that tty from the remote host. */
! 593: record_login(pid, s->tty, pw->pw_name, pw->pw_uid,
! 594: get_canonical_hostname(),
! 595: (struct sockaddr *)&from);
! 596:
! 597: /* Done if .hushlogin exists. */
! 598: snprintf(buf, sizeof(buf), "%.200s/.hushlogin", pw->pw_dir);
! 599: if (stat(buf, &st) >= 0)
! 600: return;
! 601: /*
! 602: * Get the time when the user last logged in. 'buf' will be set
! 603: * to contain the hostname the last login was from.
! 604: */
! 605: last_login_time = get_last_login_time(pw->pw_uid, pw->pw_name,
! 606: buf, sizeof(buf));
! 607: if (last_login_time != 0) {
! 608: time_string = ctime(&last_login_time);
! 609: if (strchr(time_string, '\n'))
! 610: *strchr(time_string, '\n') = 0;
! 611: if (strcmp(buf, "") == 0)
! 612: printf("Last login: %s\r\n", time_string);
! 613: else
! 614: printf("Last login: %s from %s\r\n", time_string, buf);
! 615: }
! 616: if (options.print_motd) {
! 617: f = fopen("/etc/motd", "r");
! 618: if (f) {
! 619: while (fgets(buf, sizeof(buf), f))
! 620: fputs(buf, stdout);
! 621: fclose(f);
! 622: }
1.2 markus 623: }
1.1 markus 624: }
625:
626: /*
627: * Sets the value of the given variable in the environment. If the variable
628: * already exists, its value is overriden.
629: */
1.4 markus 630: void
1.1 markus 631: child_set_env(char ***envp, unsigned int *envsizep, const char *name,
632: const char *value)
633: {
634: unsigned int i, namelen;
635: char **env;
636:
637: /*
638: * Find the slot where the value should be stored. If the variable
639: * already exists, we reuse the slot; otherwise we append a new slot
640: * at the end of the array, expanding if necessary.
641: */
642: env = *envp;
643: namelen = strlen(name);
644: for (i = 0; env[i]; i++)
645: if (strncmp(env[i], name, namelen) == 0 && env[i][namelen] == '=')
646: break;
647: if (env[i]) {
648: /* Reuse the slot. */
649: xfree(env[i]);
650: } else {
651: /* New variable. Expand if necessary. */
652: if (i >= (*envsizep) - 1) {
653: (*envsizep) += 50;
654: env = (*envp) = xrealloc(env, (*envsizep) * sizeof(char *));
655: }
656: /* Need to set the NULL pointer at end of array beyond the new slot. */
657: env[i + 1] = NULL;
658: }
659:
660: /* Allocate space and format the variable in the appropriate slot. */
661: env[i] = xmalloc(strlen(name) + 1 + strlen(value) + 1);
662: snprintf(env[i], strlen(name) + 1 + strlen(value) + 1, "%s=%s", name, value);
663: }
664:
665: /*
666: * Reads environment variables from the given file and adds/overrides them
667: * into the environment. If the file does not exist, this does nothing.
668: * Otherwise, it must consist of empty lines, comments (line starts with '#')
669: * and assignments of the form name=value. No other forms are allowed.
670: */
1.4 markus 671: void
1.1 markus 672: read_environment_file(char ***env, unsigned int *envsize,
673: const char *filename)
674: {
675: FILE *f;
676: char buf[4096];
677: char *cp, *value;
678:
679: f = fopen(filename, "r");
680: if (!f)
681: return;
682:
683: while (fgets(buf, sizeof(buf), f)) {
684: for (cp = buf; *cp == ' ' || *cp == '\t'; cp++)
685: ;
686: if (!*cp || *cp == '#' || *cp == '\n')
687: continue;
688: if (strchr(cp, '\n'))
689: *strchr(cp, '\n') = '\0';
690: value = strchr(cp, '=');
691: if (value == NULL) {
692: fprintf(stderr, "Bad line in %.100s: %.200s\n", filename, buf);
693: continue;
694: }
1.14 deraadt 695: /*
696: * Replace the equals sign by nul, and advance value to
697: * the value string.
698: */
1.1 markus 699: *value = '\0';
700: value++;
701: child_set_env(env, envsize, cp, value);
702: }
703: fclose(f);
704: }
705:
706: /*
707: * Performs common processing for the child, such as setting up the
708: * environment, closing extra file descriptors, setting the user and group
709: * ids, and executing the command or shell.
710: */
1.4 markus 711: void
1.1 markus 712: do_child(const char *command, struct passwd * pw, const char *term,
713: const char *display, const char *auth_proto,
714: const char *auth_data, const char *ttyname)
715: {
716: const char *shell, *cp = NULL;
717: char buf[256];
1.16 markus 718: char cmd[1024];
1.1 markus 719: FILE *f;
720: unsigned int envsize, i;
721: char **env;
722: extern char **environ;
723: struct stat st;
724: char *argv[10];
1.17 markus 725:
726: /* login(1) is only called if we execute the login shell */
727: if (options.use_login && command != NULL)
728: options.use_login = 0;
1.1 markus 729:
730: f = fopen("/etc/nologin", "r");
731: if (f) {
732: /* /etc/nologin exists. Print its contents and exit. */
733: while (fgets(buf, sizeof(buf), f))
734: fputs(buf, stderr);
735: fclose(f);
736: if (pw->pw_uid != 0)
737: exit(254);
738: }
739: /* Set login name in the kernel. */
740: if (setlogin(pw->pw_name) < 0)
741: error("setlogin failed: %s", strerror(errno));
742:
743: /* Set uid, gid, and groups. */
744: /* Login(1) does this as well, and it needs uid 0 for the "-h"
745: switch, so we let login(1) to this for us. */
746: if (!options.use_login) {
747: if (getuid() == 0 || geteuid() == 0) {
748: if (setgid(pw->pw_gid) < 0) {
749: perror("setgid");
750: exit(1);
751: }
752: /* Initialize the group list. */
753: if (initgroups(pw->pw_name, pw->pw_gid) < 0) {
754: perror("initgroups");
755: exit(1);
756: }
757: endgrent();
758:
759: /* Permanently switch to the desired uid. */
760: permanently_set_uid(pw->pw_uid);
761: }
762: if (getuid() != pw->pw_uid || geteuid() != pw->pw_uid)
763: fatal("Failed to set uids to %d.", (int) pw->pw_uid);
764: }
765: /*
766: * Get the shell from the password data. An empty shell field is
767: * legal, and means /bin/sh.
768: */
769: shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell;
770:
771: #ifdef AFS
772: /* Try to get AFS tokens for the local cell. */
773: if (k_hasafs()) {
774: char cell[64];
775:
776: if (k_afs_cell_of_file(pw->pw_dir, cell, sizeof(cell)) == 0)
777: krb_afslog(cell, 0);
778:
779: krb_afslog(0, 0);
780: }
781: #endif /* AFS */
782:
783: /* Initialize the environment. */
784: envsize = 100;
785: env = xmalloc(envsize * sizeof(char *));
786: env[0] = NULL;
787:
788: if (!options.use_login) {
789: /* Set basic environment. */
790: child_set_env(&env, &envsize, "USER", pw->pw_name);
791: child_set_env(&env, &envsize, "LOGNAME", pw->pw_name);
792: child_set_env(&env, &envsize, "HOME", pw->pw_dir);
793: child_set_env(&env, &envsize, "PATH", _PATH_STDPATH);
794:
795: snprintf(buf, sizeof buf, "%.200s/%.50s",
796: _PATH_MAILDIR, pw->pw_name);
797: child_set_env(&env, &envsize, "MAIL", buf);
798:
799: /* Normal systems set SHELL by default. */
800: child_set_env(&env, &envsize, "SHELL", shell);
801: }
802: if (getenv("TZ"))
803: child_set_env(&env, &envsize, "TZ", getenv("TZ"));
804:
805: /* Set custom environment options from RSA authentication. */
806: while (custom_environment) {
807: struct envstring *ce = custom_environment;
808: char *s = ce->s;
809: int i;
810: for (i = 0; s[i] != '=' && s[i]; i++);
811: if (s[i] == '=') {
812: s[i] = 0;
813: child_set_env(&env, &envsize, s, s + i + 1);
814: }
815: custom_environment = ce->next;
816: xfree(ce->s);
817: xfree(ce);
818: }
819:
820: snprintf(buf, sizeof buf, "%.50s %d %d",
821: get_remote_ipaddr(), get_remote_port(), get_local_port());
822: child_set_env(&env, &envsize, "SSH_CLIENT", buf);
823:
824: if (ttyname)
825: child_set_env(&env, &envsize, "SSH_TTY", ttyname);
826: if (term)
827: child_set_env(&env, &envsize, "TERM", term);
828: if (display)
829: child_set_env(&env, &envsize, "DISPLAY", display);
830:
831: #ifdef KRB4
832: {
833: extern char *ticket;
834:
835: if (ticket)
836: child_set_env(&env, &envsize, "KRBTKFILE", ticket);
837: }
838: #endif /* KRB4 */
839:
840: if (xauthfile)
841: child_set_env(&env, &envsize, "XAUTHORITY", xauthfile);
842: if (auth_get_socket_name() != NULL)
843: child_set_env(&env, &envsize, SSH_AUTHSOCKET_ENV_NAME,
844: auth_get_socket_name());
845:
846: /* read $HOME/.ssh/environment. */
847: if (!options.use_login) {
1.14 deraadt 848: snprintf(buf, sizeof buf, "%.200s/.ssh/environment",
849: pw->pw_dir);
1.1 markus 850: read_environment_file(&env, &envsize, buf);
851: }
852: if (debug_flag) {
853: /* dump the environment */
854: fprintf(stderr, "Environment:\n");
855: for (i = 0; env[i]; i++)
856: fprintf(stderr, " %.200s\n", env[i]);
857: }
858: /*
859: * Close the connection descriptors; note that this is the child, and
860: * the server will still have the socket open, and it is important
861: * that we do not shutdown it. Note that the descriptors cannot be
862: * closed before building the environment, as we call
863: * get_remote_ipaddr there.
864: */
865: if (packet_get_connection_in() == packet_get_connection_out())
866: close(packet_get_connection_in());
867: else {
868: close(packet_get_connection_in());
869: close(packet_get_connection_out());
870: }
871: /*
872: * Close all descriptors related to channels. They will still remain
873: * open in the parent.
874: */
875: /* XXX better use close-on-exec? -markus */
876: channel_close_all();
877:
878: /*
879: * Close any extra file descriptors. Note that there may still be
880: * descriptors left by system functions. They will be closed later.
881: */
882: endpwent();
883:
884: /*
885: * Close any extra open file descriptors so that we don\'t have them
886: * hanging around in clients. Note that we want to do this after
887: * initgroups, because at least on Solaris 2.3 it leaves file
888: * descriptors open.
889: */
890: for (i = 3; i < 64; i++)
891: close(i);
892:
893: /* Change current directory to the user\'s home directory. */
894: if (chdir(pw->pw_dir) < 0)
895: fprintf(stderr, "Could not chdir to home directory %s: %s\n",
896: pw->pw_dir, strerror(errno));
897:
898: /*
899: * Must take new environment into use so that .ssh/rc, /etc/sshrc and
900: * xauth are run in the proper environment.
901: */
902: environ = env;
903:
904: /*
905: * Run $HOME/.ssh/rc, /etc/sshrc, or xauth (whichever is found first
906: * in this order).
907: */
908: if (!options.use_login) {
909: if (stat(SSH_USER_RC, &st) >= 0) {
910: if (debug_flag)
911: fprintf(stderr, "Running /bin/sh %s\n", SSH_USER_RC);
912:
913: f = popen("/bin/sh " SSH_USER_RC, "w");
914: if (f) {
915: if (auth_proto != NULL && auth_data != NULL)
916: fprintf(f, "%s %s\n", auth_proto, auth_data);
917: pclose(f);
918: } else
919: fprintf(stderr, "Could not run %s\n", SSH_USER_RC);
920: } else if (stat(SSH_SYSTEM_RC, &st) >= 0) {
921: if (debug_flag)
922: fprintf(stderr, "Running /bin/sh %s\n", SSH_SYSTEM_RC);
923:
924: f = popen("/bin/sh " SSH_SYSTEM_RC, "w");
925: if (f) {
926: if (auth_proto != NULL && auth_data != NULL)
927: fprintf(f, "%s %s\n", auth_proto, auth_data);
928: pclose(f);
929: } else
930: fprintf(stderr, "Could not run %s\n", SSH_SYSTEM_RC);
1.16 markus 931: } else if (options.xauth_location != NULL) {
1.1 markus 932: /* Add authority data to .Xauthority if appropriate. */
933: if (auth_proto != NULL && auth_data != NULL) {
1.13 markus 934: char *screen = strchr(display, ':');
935: if (debug_flag) {
1.14 deraadt 936: fprintf(stderr,
937: "Running %.100s add %.100s %.100s %.100s\n",
1.16 markus 938: options.xauth_location, display,
939: auth_proto, auth_data);
1.13 markus 940: if (screen != NULL)
1.14 deraadt 941: fprintf(stderr,
942: "Adding %.*s/unix%s %s %s\n",
943: screen-display, display,
944: screen, auth_proto, auth_data);
1.13 markus 945: }
1.16 markus 946: snprintf(cmd, sizeof cmd, "%s -q -",
947: options.xauth_location);
948: f = popen(cmd, "w");
1.1 markus 949: if (f) {
1.14 deraadt 950: fprintf(f, "add %s %s %s\n", display,
951: auth_proto, auth_data);
1.13 markus 952: if (screen != NULL)
953: fprintf(f, "add %.*s/unix%s %s %s\n",
1.14 deraadt 954: screen-display, display,
955: screen, auth_proto, auth_data);
1.1 markus 956: pclose(f);
1.16 markus 957: } else {
958: fprintf(stderr, "Could not run %s\n",
959: cmd);
960: }
1.1 markus 961: }
962: }
963: /* Get the last component of the shell name. */
964: cp = strrchr(shell, '/');
965: if (cp)
966: cp++;
967: else
968: cp = shell;
969: }
970: /*
971: * If we have no command, execute the shell. In this case, the shell
972: * name to be passed in argv[0] is preceded by '-' to indicate that
973: * this is a login shell.
974: */
975: if (!command) {
976: if (!options.use_login) {
977: char buf[256];
978:
979: /*
980: * Check for mail if we have a tty and it was enabled
981: * in server options.
982: */
983: if (ttyname && options.check_mail) {
984: char *mailbox;
985: struct stat mailstat;
986: mailbox = getenv("MAIL");
987: if (mailbox != NULL) {
1.14 deraadt 988: if (stat(mailbox, &mailstat) != 0 ||
989: mailstat.st_size == 0)
1.1 markus 990: printf("No mail.\n");
991: else if (mailstat.st_mtime < mailstat.st_atime)
992: printf("You have mail.\n");
993: else
994: printf("You have new mail.\n");
995: }
996: }
997: /* Start the shell. Set initial character to '-'. */
998: buf[0] = '-';
999: strncpy(buf + 1, cp, sizeof(buf) - 1);
1000: buf[sizeof(buf) - 1] = 0;
1001:
1002: /* Execute the shell. */
1003: argv[0] = buf;
1004: argv[1] = NULL;
1005: execve(shell, argv, env);
1006:
1007: /* Executing the shell failed. */
1008: perror(shell);
1009: exit(1);
1010:
1011: } else {
1012: /* Launch login(1). */
1013:
1014: execl("/usr/bin/login", "login", "-h", get_remote_ipaddr(),
1015: "-p", "-f", "--", pw->pw_name, NULL);
1016:
1017: /* Login couldn't be executed, die. */
1018:
1019: perror("login");
1020: exit(1);
1021: }
1022: }
1023: /*
1024: * Execute the command using the user's shell. This uses the -c
1025: * option to execute the command.
1026: */
1027: argv[0] = (char *) cp;
1028: argv[1] = "-c";
1029: argv[2] = (char *) command;
1030: argv[3] = NULL;
1031: execve(shell, argv, env);
1032: perror(shell);
1033: exit(1);
1034: }
1035:
1036: Session *
1037: session_new(void)
1038: {
1039: int i;
1040: static int did_init = 0;
1041: if (!did_init) {
1042: debug("session_new: init");
1043: for(i = 0; i < MAX_SESSIONS; i++) {
1044: sessions[i].used = 0;
1045: sessions[i].self = i;
1046: }
1047: did_init = 1;
1048: }
1049: for(i = 0; i < MAX_SESSIONS; i++) {
1050: Session *s = &sessions[i];
1051: if (! s->used) {
1052: s->pid = 0;
1.7 markus 1053: s->extended = 0;
1.1 markus 1054: s->chanid = -1;
1055: s->ptyfd = -1;
1056: s->ttyfd = -1;
1057: s->term = NULL;
1058: s->pw = NULL;
1059: s->display = NULL;
1060: s->screen = 0;
1061: s->auth_data = NULL;
1062: s->auth_proto = NULL;
1063: s->used = 1;
1.7 markus 1064: s->pw = NULL;
1.1 markus 1065: debug("session_new: session %d", i);
1066: return s;
1067: }
1068: }
1069: return NULL;
1070: }
1071:
1072: void
1073: session_dump(void)
1074: {
1075: int i;
1076: for(i = 0; i < MAX_SESSIONS; i++) {
1077: Session *s = &sessions[i];
1078: debug("dump: used %d session %d %p channel %d pid %d",
1079: s->used,
1080: s->self,
1081: s,
1082: s->chanid,
1083: s->pid);
1084: }
1085: }
1086:
1.2 markus 1087: int
1088: session_open(int chanid)
1089: {
1090: Session *s = session_new();
1091: debug("session_open: channel %d", chanid);
1092: if (s == NULL) {
1093: error("no more sessions");
1094: return 0;
1095: }
1.7 markus 1096: s->pw = auth_get_user();
1097: if (s->pw == NULL)
1098: fatal("no user for session %i", s->self);
1.2 markus 1099: debug("session_open: session %d: link with channel %d", s->self, chanid);
1100: s->chanid = chanid;
1101: return 1;
1102: }
1103:
1104: Session *
1105: session_by_channel(int id)
1106: {
1107: int i;
1108: for(i = 0; i < MAX_SESSIONS; i++) {
1109: Session *s = &sessions[i];
1110: if (s->used && s->chanid == id) {
1111: debug("session_by_channel: session %d channel %d", i, id);
1112: return s;
1113: }
1114: }
1115: debug("session_by_channel: unknown channel %d", id);
1116: session_dump();
1117: return NULL;
1118: }
1119:
1120: Session *
1121: session_by_pid(pid_t pid)
1122: {
1123: int i;
1124: debug("session_by_pid: pid %d", pid);
1125: for(i = 0; i < MAX_SESSIONS; i++) {
1126: Session *s = &sessions[i];
1127: if (s->used && s->pid == pid)
1128: return s;
1129: }
1130: error("session_by_pid: unknown pid %d", pid);
1131: session_dump();
1132: return NULL;
1133: }
1134:
1135: int
1136: session_window_change_req(Session *s)
1137: {
1138: s->col = packet_get_int();
1139: s->row = packet_get_int();
1140: s->xpixel = packet_get_int();
1141: s->ypixel = packet_get_int();
1.3 markus 1142: packet_done();
1.2 markus 1143: pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
1144: return 1;
1145: }
1146:
1147: int
1148: session_pty_req(Session *s)
1149: {
1150: unsigned int len;
1.3 markus 1151: char *term_modes; /* encoded terminal modes */
1.2 markus 1152:
1.19 markus 1153: if (no_pty_flag)
1154: return 0;
1.2 markus 1155: if (s->ttyfd != -1)
1.3 markus 1156: return 0;
1.2 markus 1157: s->term = packet_get_string(&len);
1158: s->col = packet_get_int();
1159: s->row = packet_get_int();
1160: s->xpixel = packet_get_int();
1161: s->ypixel = packet_get_int();
1.3 markus 1162: term_modes = packet_get_string(&len);
1163: packet_done();
1.2 markus 1164:
1165: if (strcmp(s->term, "") == 0) {
1166: xfree(s->term);
1167: s->term = NULL;
1168: }
1169: /* Allocate a pty and open it. */
1170: if (!pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty))) {
1171: xfree(s->term);
1172: s->term = NULL;
1173: s->ptyfd = -1;
1174: s->ttyfd = -1;
1175: error("session_pty_req: session %d alloc failed", s->self);
1.3 markus 1176: xfree(term_modes);
1177: return 0;
1.2 markus 1178: }
1179: debug("session_pty_req: session %d alloc %s", s->self, s->tty);
1180: /*
1181: * Add a cleanup function to clear the utmp entry and record logout
1182: * time in case we call fatal() (e.g., the connection gets closed).
1183: */
1184: fatal_add_cleanup(pty_cleanup_proc, (void *)s);
1185: pty_setowner(s->pw, s->tty);
1186: /* Get window size from the packet. */
1187: pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
1188:
1.9 markus 1189: session_proctitle(s);
1190:
1.3 markus 1191: /* XXX parse and set terminal modes */
1192: xfree(term_modes);
1.2 markus 1193: return 1;
1194: }
1195:
1.7 markus 1196: int
1197: session_subsystem_req(Session *s)
1198: {
1199: unsigned int len;
1200: int success = 0;
1201: char *subsys = packet_get_string(&len);
1.18 jakob 1202: int i;
1.7 markus 1203:
1204: packet_done();
1205: log("subsystem request for %s", subsys);
1.18 jakob 1206:
1207: for (i = 0; i < options.num_subsystems; i++) {
1208: if(strcmp(subsys, options.subsystem_name[i]) == 0) {
1209: debug("subsystem: exec() %s", options.subsystem_command[i]);
1210: do_exec_no_pty(s, options.subsystem_command[i], s->pw);
1211: success = 1;
1212: }
1213: }
1214:
1215: if (!success)
1216: log("subsystem request for %s failed, subsystem not found", subsys);
1.7 markus 1217:
1218: xfree(subsys);
1219: return success;
1220: }
1221:
1222: int
1223: session_x11_req(Session *s)
1224: {
1.22 deraadt 1225: if (no_x11_forwarding_flag) {
1.19 markus 1226: debug("X11 forwarding disabled in user configuration file.");
1227: return 0;
1228: }
1.7 markus 1229: if (!options.x11_forwarding) {
1230: debug("X11 forwarding disabled in server configuration file.");
1231: return 0;
1232: }
1233: if (xauthfile != NULL) {
1234: debug("X11 fwd already started.");
1235: return 0;
1236: }
1237:
1238: debug("Received request for X11 forwarding with auth spoofing.");
1239: if (s->display != NULL)
1240: packet_disconnect("Protocol error: X11 display already set.");
1241:
1242: s->single_connection = packet_get_char();
1243: s->auth_proto = packet_get_string(NULL);
1244: s->auth_data = packet_get_string(NULL);
1245: s->screen = packet_get_int();
1246: packet_done();
1247:
1248: s->display = x11_create_display_inet(s->screen, options.x11_display_offset);
1249: if (s->display == NULL) {
1250: xfree(s->auth_proto);
1251: xfree(s->auth_data);
1252: return 0;
1253: }
1254: xauthfile = xmalloc(MAXPATHLEN);
1255: strlcpy(xauthfile, "/tmp/ssh-XXXXXXXX", MAXPATHLEN);
1256: temporarily_use_uid(s->pw->pw_uid);
1257: if (mkdtemp(xauthfile) == NULL) {
1258: restore_uid();
1259: error("private X11 dir: mkdtemp %s failed: %s",
1260: xauthfile, strerror(errno));
1261: xfree(xauthfile);
1262: xauthfile = NULL;
1263: xfree(s->auth_proto);
1264: xfree(s->auth_data);
1265: /* XXXX remove listening channels */
1266: return 0;
1267: }
1268: strlcat(xauthfile, "/cookies", MAXPATHLEN);
1269: open(xauthfile, O_RDWR|O_CREAT|O_EXCL, 0600);
1270: restore_uid();
1271: fatal_add_cleanup(xauthfile_cleanup_proc, s);
1272: return 1;
1273: }
1274:
1.19 markus 1275: int
1276: session_shell_req(Session *s)
1277: {
1278: /* if forced_command == NULL, the shell is execed */
1279: char *shell = forced_command;
1280: packet_done();
1281: s->extended = 1;
1282: if (s->ttyfd == -1)
1283: do_exec_no_pty(s, shell, s->pw);
1284: else
1285: do_exec_pty(s, shell, s->pw);
1286: return 1;
1287: }
1288:
1289: int
1290: session_exec_req(Session *s)
1291: {
1.20 markus 1292: unsigned int len;
1.19 markus 1293: char *command = packet_get_string(&len);
1294: packet_done();
1295: if (forced_command) {
1296: xfree(command);
1297: command = forced_command;
1298: debug("Forced command '%.500s'", forced_command);
1299: }
1300: s->extended = 1;
1301: if (s->ttyfd == -1)
1302: do_exec_no_pty(s, command, s->pw);
1303: else
1304: do_exec_pty(s, command, s->pw);
1305: if (forced_command == NULL)
1306: xfree(command);
1307: return 1;
1308: }
1309:
1.2 markus 1310: void
1311: session_input_channel_req(int id, void *arg)
1312: {
1313: unsigned int len;
1314: int reply;
1315: int success = 0;
1316: char *rtype;
1317: Session *s;
1318: Channel *c;
1319:
1320: rtype = packet_get_string(&len);
1321: reply = packet_get_char();
1322:
1323: s = session_by_channel(id);
1324: if (s == NULL)
1325: fatal("session_input_channel_req: channel %d: no session", id);
1326: c = channel_lookup(id);
1327: if (c == NULL)
1328: fatal("session_input_channel_req: channel %d: bad channel", id);
1329:
1330: debug("session_input_channel_req: session %d channel %d request %s reply %d",
1331: s->self, id, rtype, reply);
1332:
1333: /*
1334: * a session is in LARVAL state until a shell
1335: * or programm is executed
1336: */
1337: if (c->type == SSH_CHANNEL_LARVAL) {
1338: if (strcmp(rtype, "shell") == 0) {
1.19 markus 1339: success = session_shell_req(s);
1.2 markus 1340: } else if (strcmp(rtype, "exec") == 0) {
1.19 markus 1341: success = session_exec_req(s);
1.2 markus 1342: } else if (strcmp(rtype, "pty-req") == 0) {
1.3 markus 1343: success = session_pty_req(s);
1.7 markus 1344: } else if (strcmp(rtype, "x11-req") == 0) {
1345: success = session_x11_req(s);
1346: } else if (strcmp(rtype, "subsystem") == 0) {
1347: success = session_subsystem_req(s);
1.2 markus 1348: }
1349: }
1350: if (strcmp(rtype, "window-change") == 0) {
1351: success = session_window_change_req(s);
1352: }
1353:
1354: if (reply) {
1355: packet_start(success ?
1356: SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
1357: packet_put_int(c->remote_id);
1358: packet_send();
1359: }
1360: xfree(rtype);
1361: }
1362:
1363: void
1364: session_set_fds(Session *s, int fdin, int fdout, int fderr)
1365: {
1366: if (!compat20)
1367: fatal("session_set_fds: called for proto != 2.0");
1368: /*
1369: * now that have a child and a pipe to the child,
1370: * we can activate our channel and register the fd's
1371: */
1372: if (s->chanid == -1)
1373: fatal("no channel for session %d", s->self);
1374: channel_set_fds(s->chanid,
1375: fdout, fdin, fderr,
1376: fderr == -1 ? CHAN_EXTENDED_IGNORE : CHAN_EXTENDED_READ);
1377: }
1378:
1.1 markus 1379: void
1380: session_pty_cleanup(Session *s)
1381: {
1382: if (s == NULL || s->ttyfd == -1)
1383: return;
1384:
1385: debug("session_pty_cleanup: session %i release %s", s->self, s->tty);
1386:
1387: /* Cancel the cleanup function. */
1388: fatal_remove_cleanup(pty_cleanup_proc, (void *)s);
1389:
1390: /* Record that the user has logged out. */
1391: record_logout(s->pid, s->tty);
1392:
1393: /* Release the pseudo-tty. */
1394: pty_release(s->tty);
1395:
1396: /*
1397: * Close the server side of the socket pairs. We must do this after
1398: * the pty cleanup, so that another process doesn't get this pty
1399: * while we're still cleaning up.
1400: */
1401: if (close(s->ptymaster) < 0)
1402: error("close(s->ptymaster): %s", strerror(errno));
1.2 markus 1403: }
1404:
1405: void
1406: session_exit_message(Session *s, int status)
1407: {
1408: Channel *c;
1409: if (s == NULL)
1410: fatal("session_close: no session");
1411: c = channel_lookup(s->chanid);
1412: if (c == NULL)
1413: fatal("session_close: session %d: no channel %d",
1414: s->self, s->chanid);
1415: debug("session_exit_message: session %d channel %d pid %d",
1416: s->self, s->chanid, s->pid);
1417:
1418: if (WIFEXITED(status)) {
1419: channel_request_start(s->chanid,
1420: "exit-status", 0);
1421: packet_put_int(WEXITSTATUS(status));
1422: packet_send();
1423: } else if (WIFSIGNALED(status)) {
1424: channel_request_start(s->chanid,
1425: "exit-signal", 0);
1426: packet_put_int(WTERMSIG(status));
1427: packet_put_char(WCOREDUMP(status));
1428: packet_put_cstring("");
1429: packet_put_cstring("");
1430: packet_send();
1431: } else {
1432: /* Some weird exit cause. Just exit. */
1433: packet_disconnect("wait returned status %04x.", status);
1434: }
1435:
1436: /* disconnect channel */
1437: debug("session_exit_message: release channel %d", s->chanid);
1438: channel_cancel_cleanup(s->chanid);
1.5 markus 1439: /*
1440: * emulate a write failure with 'chan_write_failed', nobody will be
1441: * interested in data we write.
1442: * Note that we must not call 'chan_read_failed', since there could
1443: * be some more data waiting in the pipe.
1444: */
1.8 markus 1445: if (c->ostate != CHAN_OUTPUT_CLOSED)
1446: chan_write_failed(c);
1.2 markus 1447: s->chanid = -1;
1448: }
1449:
1450: void
1451: session_free(Session *s)
1452: {
1453: debug("session_free: session %d pid %d", s->self, s->pid);
1454: if (s->term)
1455: xfree(s->term);
1456: if (s->display)
1457: xfree(s->display);
1458: if (s->auth_data)
1459: xfree(s->auth_data);
1460: if (s->auth_proto)
1461: xfree(s->auth_proto);
1462: s->used = 0;
1463: }
1464:
1465: void
1466: session_close(Session *s)
1467: {
1468: session_pty_cleanup(s);
1469: session_free(s);
1.9 markus 1470: session_proctitle(s);
1.2 markus 1471: }
1472:
1473: void
1474: session_close_by_pid(pid_t pid, int status)
1475: {
1476: Session *s = session_by_pid(pid);
1477: if (s == NULL) {
1478: debug("session_close_by_pid: no session for pid %d", s->pid);
1479: return;
1480: }
1481: if (s->chanid != -1)
1482: session_exit_message(s, status);
1483: session_close(s);
1484: }
1485:
1486: /*
1487: * this is called when a channel dies before
1488: * the session 'child' itself dies
1489: */
1490: void
1491: session_close_by_channel(int id, void *arg)
1492: {
1493: Session *s = session_by_channel(id);
1494: if (s == NULL) {
1495: debug("session_close_by_channel: no session for channel %d", id);
1496: return;
1497: }
1498: /* disconnect channel */
1499: channel_cancel_cleanup(s->chanid);
1500: s->chanid = -1;
1501:
1502: debug("session_close_by_channel: channel %d kill %d", id, s->pid);
1503: if (s->pid == 0) {
1504: /* close session immediately */
1505: session_close(s);
1506: } else {
1507: /* notify child, delay session cleanup */
1508: if (kill(s->pid, (s->ttyfd == -1) ? SIGTERM : SIGHUP) < 0)
1509: error("session_close_by_channel: kill %d: %s",
1510: s->pid, strerror(errno));
1511: }
1.9 markus 1512: }
1513:
1514: char *
1515: session_tty_list(void)
1516: {
1517: static char buf[1024];
1518: int i;
1519: buf[0] = '\0';
1520: for(i = 0; i < MAX_SESSIONS; i++) {
1521: Session *s = &sessions[i];
1522: if (s->used && s->ttyfd != -1) {
1523: if (buf[0] != '\0')
1524: strlcat(buf, ",", sizeof buf);
1525: strlcat(buf, strrchr(s->tty, '/') + 1, sizeof buf);
1526: }
1527: }
1528: if (buf[0] == '\0')
1529: strlcpy(buf, "notty", sizeof buf);
1530: return buf;
1531: }
1532:
1533: void
1534: session_proctitle(Session *s)
1535: {
1536: if (s->pw == NULL)
1537: error("no user for session %d", s->self);
1538: else
1539: setproctitle("%s@%s", s->pw->pw_name, session_tty_list());
1.2 markus 1540: }
1541:
1542: void
1543: do_authenticated2(void)
1544: {
1545: /*
1546: * Cancel the alarm we set to limit the time taken for
1547: * authentication.
1548: */
1549: alarm(0);
1.23 deraadt 1550: if (startup_pipe != -1) {
1551: close(startup_pipe);
1552: startup_pipe = -1;
1553: }
1.2 markus 1554: server_loop2();
1.7 markus 1555: if (xauthfile)
1556: xauthfile_cleanup_proc(NULL);
1.1 markus 1557: }
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