aft: Change return type of make_status_items() to void.
[paraslash.git] / client_common.c
1 /* Copyright (C) 1997 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
2
3 /** \file client_common.c Common functions of para_client and para_audiod. */
4
5 #include <netinet/in.h>
6 #include <sys/socket.h>
7 #include <regex.h>
8 #include <sys/types.h>
9 #include <arpa/inet.h>
10 #include <sys/un.h>
11 #include <netdb.h>
12 #include <lopsub.h>
13
14 #include "client.lsg.h"
15 #include "para.h"
16 #include "error.h"
17 #include "list.h"
18 #include "lsu.h"
19 #include "sched.h"
20 #include "crypt.h"
21 #include "net.h"
22 #include "fd.h"
23 #include "sideband.h"
24 #include "string.h"
25 #include "client.h"
26 #include "buffer_tree.h"
27 #include "version.h"
28
29 /** The size of the receiving buffer. */
30 #define CLIENT_BUFSIZE 4000
31
32 /**
33 * Close the connection to para_server and free all resources.
34 *
35 * \param ct Pointer to the client data.
36 *
37 * \sa \ref client_open().
38 */
39 void client_close(struct client_task *ct)
40 {
41 if (!ct)
42 return;
43 free(ct->user);
44 free(ct->key_file);
45 lls_free_parse_result(ct->lpr, CLIENT_CMD_PTR);
46 free(ct->challenge_hash);
47 sb_free(ct->sbc[0]);
48 sb_free(ct->sbc[1]);
49 free(ct);
50 }
51
52 /*
53 * The preselect hook for server commands.
54 *
55 * The task pointer must contain a pointer to the initialized client data
56 * structure as it is returned by client_open().
57 *
58 * This function checks the state of the connection and adds the file descriptor
59 * of the connection to the read or write fd set of s accordingly.
60 */
61 static void client_pre_select(struct sched *s, void *context)
62 {
63 int ret;
64 struct client_task *ct = context;
65
66 if (ct->scc.fd < 0)
67 return;
68 switch (ct->status) {
69 case CL_CONNECTED:
70 case CL_SENT_AUTH:
71 case CL_SENT_CH_RESPONSE:
72 para_fd_set(ct->scc.fd, &s->rfds, &s->max_fileno);
73 return;
74
75 case CL_RECEIVED_WELCOME:
76 case CL_RECEIVED_PROCEED:
77 case CL_RECEIVED_CHALLENGE:
78 para_fd_set(ct->scc.fd, &s->wfds, &s->max_fileno);
79 return;
80
81 case CL_SENDING:
82 if (ct->btrn[1]) {
83 ret = btr_node_status(ct->btrn[1], 0, BTR_NT_LEAF);
84 if (ret < 0)
85 sched_min_delay(s);
86 else if (ret > 0)
87 para_fd_set(ct->scc.fd, &s->wfds, &s->max_fileno);
88 }
89 /* fallthrough */
90 case CL_EXECUTING:
91 if (ct->btrn[0]) {
92 ret = btr_node_status(ct->btrn[0], 0, BTR_NT_ROOT);
93 if (ret < 0)
94 sched_min_delay(s);
95 else if (ret > 0)
96 para_fd_set(ct->scc.fd, &s->rfds, &s->max_fileno);
97 }
98 return;
99 }
100 }
101
102 static int send_sb(struct client_task *ct, int channel, void *buf, size_t numbytes,
103 enum sb_designator band, bool dont_free)
104 {
105 int ret, fd = ct->scc.fd;
106 struct iovec iov[2];
107
108 if (!ct->sbc[channel]) {
109 struct sb_buffer sbb;
110 sb_transformation trafo = ct->status < CL_RECEIVED_PROCEED?
111 NULL : sc_trafo;
112 sbb = (typeof(sbb))SBB_INIT(band, buf, numbytes);
113 ct->sbc[channel] = sb_new_send(&sbb, dont_free, trafo, ct->scc.send);
114 }
115 ret = sb_get_send_buffers(ct->sbc[channel], iov);
116 ret = xwritev(fd, iov, ret);
117 if (ret < 0) {
118 sb_free(ct->sbc[channel]);
119 ct->sbc[channel] = NULL;
120 return ret;
121 }
122 if (sb_sent(ct->sbc[channel], ret)) {
123 ct->sbc[channel] = NULL;
124 return 1;
125 }
126 return 0;
127 }
128
129 static int recv_sb(struct client_task *ct, fd_set *rfds,
130 struct sb_buffer *result)
131 {
132 int ret;
133 size_t n;
134 sb_transformation trafo;
135 void *trafo_context;
136 struct iovec iov;
137
138 if (!FD_ISSET(ct->scc.fd, rfds))
139 return 0;
140 if (ct->status < CL_SENT_CH_RESPONSE)
141 trafo = trafo_context = NULL;
142 else {
143 trafo = sc_trafo;
144 trafo_context = ct->scc.recv;
145 }
146 if (!ct->sbc[0])
147 ct->sbc[0] = sb_new_recv(0, trafo, trafo_context);
148 again:
149 sb_get_recv_buffer(ct->sbc[0], &iov);
150 ret = read_nonblock(ct->scc.fd, iov.iov_base, iov.iov_len, rfds, &n);
151 if (ret < 0) {
152 sb_free(ct->sbc[0]);
153 ct->sbc[0] = NULL;
154 return ret;
155 }
156 if (n == 0)
157 return 0;
158 ret = sb_received(ct->sbc[0], n, result);
159 if (ret < 0)
160 return ret;
161 if (ret == 0)
162 goto again;
163 ct->sbc[0] = NULL;
164 return 1;
165 }
166
167
168 static char **parse_features(char *buf)
169 {
170 int i;
171 const char id[] = "\nFeatures: ";
172 char *p, *q, **features;
173
174 p = strstr(buf, id);
175 if (!p)
176 return NULL;
177 p += strlen(id);
178 q = strchr(p, '\n');
179 if (!q)
180 return NULL;
181 *q = '\0';
182 create_argv(p, ",", &features);
183 for (i = 0; features[i]; i++)
184 PARA_INFO_LOG("server feature: %s\n", features[i]);
185 return features;
186 }
187
188 static int dispatch_sbb(struct client_task *ct, struct sb_buffer *sbb)
189 {
190 int ret;
191 const char *designator[] = {SB_DESIGNATORS_ARRAY};
192
193 if (!sbb)
194 return 0;
195 if (sbb->band < NUM_SB_DESIGNATORS)
196 PARA_DEBUG_LOG("band: %s\n", designator[sbb->band]);
197
198 switch (sbb->band) {
199 case SBD_AWAITING_DATA:
200 ct->status = CL_SENDING;
201 ret = 1;
202 goto out;
203 case SBD_OUTPUT:
204 if (iov_valid(&sbb->iov))
205 btr_add_output(sbb->iov.iov_base, sbb->iov.iov_len,
206 ct->btrn[0]);
207 ret = 1;
208 goto out;
209 case SBD_DEBUG_LOG:
210 case SBD_INFO_LOG:
211 case SBD_NOTICE_LOG:
212 case SBD_WARNING_LOG:
213 case SBD_ERROR_LOG:
214 case SBD_CRIT_LOG:
215 case SBD_EMERG_LOG:
216 if (iov_valid(&sbb->iov)) {
217 int ll = sbb->band - SBD_DEBUG_LOG;
218 para_log(ll, "remote: %s", (char *)sbb->iov.iov_base);
219 }
220 ret = 1;
221 goto deallocate;
222 case SBD_EXIT__SUCCESS:
223 ret = -E_SERVER_CMD_SUCCESS;
224 goto deallocate;
225 case SBD_EXIT__FAILURE:
226 ret = -E_SERVER_CMD_FAILURE;
227 goto deallocate;
228 default:
229 PARA_ERROR_LOG("invalid band %d\n", sbb->band);
230 ret = -E_BAD_BAND;
231 goto deallocate;
232 }
233 deallocate:
234 free(sbb->iov.iov_base);
235 out:
236 sbb->iov.iov_base = NULL;
237 return ret;
238 }
239
240 static int send_sb_command(struct client_task *ct)
241 {
242 int i;
243 char *command, *p;
244 size_t len = 0;
245 unsigned num_inputs = lls_num_inputs(ct->lpr);
246
247 if (ct->sbc[1])
248 return send_sb(ct, 0, NULL, 0, 0, false);
249
250 for (i = 0; i < num_inputs; i++)
251 len += strlen(lls_input(i, ct->lpr)) + 1;
252 p = command = para_malloc(len);
253 for (i = 0; i < num_inputs; i++) {
254 const char *str = lls_input(i, ct->lpr);
255 strcpy(p, str);
256 p += strlen(str) + 1;
257 }
258 PARA_DEBUG_LOG("--> %s\n", command);
259 return send_sb(ct, 0, command, len, SBD_COMMAND, false);
260 }
261
262 /*
263 * The post select hook for client commands.
264 *
265 * Depending on the current state of the connection and the status of the read
266 * and write fd sets of s, this function performs the necessary steps to
267 * authenticate the connection, to send the command given by t->private_data
268 * and to receive para_server's output, if any.
269 */
270 static int client_post_select(struct sched *s, void *context)
271 {
272 struct client_task *ct = context;
273 int ret = 0;
274 size_t n;
275 char buf[CLIENT_BUFSIZE];
276
277 ret = task_get_notification(ct->task);
278 if (ret < 0)
279 goto out;
280 if (ct->scc.fd < 0)
281 return 0;
282 switch (ct->status) {
283 case CL_CONNECTED: /* receive welcome message */
284 ret = read_nonblock(ct->scc.fd, buf, sizeof(buf), &s->rfds, &n);
285 if (ret < 0 || n == 0)
286 goto out;
287 ct->features = parse_features(buf);
288 ct->status = CL_RECEIVED_WELCOME;
289 return 0;
290 case CL_RECEIVED_WELCOME: /* send auth command */
291 if (!FD_ISSET(ct->scc.fd, &s->wfds))
292 return 0;
293 sprintf(buf, AUTH_REQUEST_MSG "%s sideband,aes_ctr128",
294 ct->user);
295 PARA_INFO_LOG("--> %s\n", buf);
296 ret = write_buffer(ct->scc.fd, buf);
297 if (ret < 0)
298 goto out;
299 ct->status = CL_SENT_AUTH;
300 return 0;
301 case CL_SENT_AUTH:
302 /*
303 * Receive challenge and session keys, decrypt the challenge and
304 * send back the hash of the decrypted challenge.
305 */
306 {
307 /* decrypted challenge/session key buffer */
308 unsigned char crypt_buf[1024];
309 struct sb_buffer sbb;
310
311 ret = recv_sb(ct, &s->rfds, &sbb);
312 if (ret <= 0)
313 goto out;
314 if (sbb.band != SBD_CHALLENGE) {
315 ret = -E_BAD_BAND;
316 free(sbb.iov.iov_base);
317 goto out;
318 }
319 n = sbb.iov.iov_len;
320 PARA_INFO_LOG("<-- [challenge] (%zu bytes)\n", n);
321 ret = apc_priv_decrypt(ct->key_file, crypt_buf,
322 sbb.iov.iov_base, n);
323 free(sbb.iov.iov_base);
324 if (ret < 0)
325 goto out;
326 ct->challenge_hash = para_malloc(HASH_SIZE);
327 hash_function((char *)crypt_buf, APC_CHALLENGE_SIZE, ct->challenge_hash);
328 ct->scc.send = sc_new(crypt_buf + APC_CHALLENGE_SIZE, SESSION_KEY_LEN);
329 ct->scc.recv = sc_new(crypt_buf + APC_CHALLENGE_SIZE + SESSION_KEY_LEN,
330 SESSION_KEY_LEN);
331 hash_to_asc(ct->challenge_hash, buf);
332 PARA_INFO_LOG("--> %s\n", buf);
333 ct->status = CL_RECEIVED_CHALLENGE;
334 return 0;
335 }
336 case CL_RECEIVED_CHALLENGE:
337 ret = send_sb(ct, 0, ct->challenge_hash, HASH_SIZE,
338 SBD_CHALLENGE_RESPONSE, false);
339 if (ret != 0)
340 ct->challenge_hash = NULL;
341 if (ret <= 0)
342 goto out;
343 ct->status = CL_SENT_CH_RESPONSE;
344 goto out;
345 case CL_SENT_CH_RESPONSE: /* read server response */
346 {
347 struct sb_buffer sbb;
348 ret = recv_sb(ct, &s->rfds, &sbb);
349 if (ret <= 0)
350 goto out;
351 free(sbb.iov.iov_base);
352 if (sbb.band != SBD_PROCEED)
353 ret = -E_BAD_BAND;
354 else
355 ct->status = CL_RECEIVED_PROCEED;
356 goto out;
357 }
358 case CL_RECEIVED_PROCEED: /* concat args and send command */
359 {
360 if (!FD_ISSET(ct->scc.fd, &s->wfds))
361 return 0;
362 ret = send_sb_command(ct);
363 if (ret <= 0)
364 goto out;
365 ct->status = CL_EXECUTING;
366 return 0;
367 }
368 case CL_SENDING:
369 if (ct->btrn[1]) {
370 char *buf2;
371 size_t sz;
372 ret = btr_node_status(ct->btrn[1], 0, BTR_NT_LEAF);
373 if (ret == -E_BTR_EOF) {
374 /* empty blob data packet indicates EOF */
375 PARA_INFO_LOG("blob sent\n");
376 ret = send_sb(ct, 1, NULL, 0, SBD_BLOB_DATA, true);
377 if (ret >= 0)
378 ret = -E_BTR_EOF;
379 }
380 if (ret < 0)
381 goto close1;
382 if (ret > 0 && FD_ISSET(ct->scc.fd, &s->wfds)) {
383 sz = btr_next_buffer(ct->btrn[1], &buf2);
384 assert(sz);
385 ret = send_sb(ct, 1, buf2, sz, SBD_BLOB_DATA, true);
386 if (ret < 0)
387 goto close1;
388 if (ret > 0)
389 btr_consume(ct->btrn[1], sz);
390 }
391 }
392 /* fall through */
393 case CL_EXECUTING:
394 if (ct->btrn[0]) {
395 ret = btr_node_status(ct->btrn[0], 0, BTR_NT_ROOT);
396 if (ret < 0)
397 goto close0;
398 if (ret > 0 && FD_ISSET(ct->scc.fd, &s->rfds)) {
399 struct sb_buffer sbb;
400 ret = recv_sb(ct, &s->rfds, &sbb);
401 if (ret < 0)
402 goto close0;
403 if (ret > 0) {
404 ret = dispatch_sbb(ct, &sbb);
405 if (ret < 0)
406 goto close0;
407 }
408 }
409 }
410 ret = 0;
411 goto out;
412 }
413 close1:
414 PARA_INFO_LOG("channel 1: %s\n", para_strerror(-ret));
415 btr_remove_node(&ct->btrn[1]);
416 if (ct->btrn[0])
417 return 0;
418 goto out;
419 close0:
420 PARA_INFO_LOG("channel 0: %s\n", para_strerror(-ret));
421 btr_remove_node(&ct->btrn[0]);
422 if (ct->btrn[1] && ct->status == CL_SENDING)
423 return 0;
424 out:
425 if (ret >= 0)
426 return 0;
427 btr_remove_node(&ct->btrn[0]);
428 btr_remove_node(&ct->btrn[1]);
429 if (ret != -E_SERVER_CMD_SUCCESS && ret != -E_SERVER_CMD_FAILURE)
430 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
431 if (ct->scc.fd >= 0) {
432 close(ct->scc.fd);
433 ct->scc.fd = -1;
434 }
435 free_argv(ct->features);
436 ct->features = NULL;
437 sc_free(ct->scc.recv);
438 ct->scc.recv = NULL;
439 sc_free(ct->scc.send);
440 ct->scc.send = NULL;
441 return ret;
442 }
443
444 /**
445 * Connect to para_server and register the client task.
446 *
447 * \param ct The initialized client task structure.
448 * \param s The scheduler instance to register the client task to.
449 * \param parent The parent node of the client btr node.
450 * \param child The child node of the client node.
451 *
452 * The client task structure given by \a ct must be allocated and initialized
453 * by \ref client_parse_config() before this function is called.
454 *
455 * \return Standard.
456 */
457 int client_connect(struct client_task *ct, struct sched *s,
458 struct btr_node *parent, struct btr_node *child)
459 {
460 int ret;
461 const char *host = CLIENT_OPT_STRING_VAL(HOSTNAME, ct->lpr);
462 uint32_t port = CLIENT_OPT_UINT32_VAL(SERVER_PORT, ct->lpr);
463
464 PARA_NOTICE_LOG("connecting %s:%u\n", host, port);
465 ct->scc.fd = -1;
466 ret = para_connect_simple(IPPROTO_TCP, host, port);
467 if (ret < 0)
468 return ret;
469 ct->scc.fd = ret;
470 ret = mark_fd_nonblocking(ct->scc.fd);
471 if (ret < 0)
472 goto err_out;
473 ct->status = CL_CONNECTED;
474 ct->btrn[0] = btr_new_node(&(struct btr_node_description)
475 EMBRACE(.name = "client recv", .parent = NULL, .child = child));
476 ct->btrn[1] = btr_new_node(&(struct btr_node_description)
477 EMBRACE(.name = "client send", .parent = parent, .child = NULL));
478
479 ct->task = task_register(&(struct task_info) {
480 .name = "client",
481 .pre_select = client_pre_select,
482 .post_select = client_post_select,
483 .context = ct,
484 }, s);
485 return 1;
486 err_out:
487 close(ct->scc.fd);
488 ct->scc.fd = -1;
489 return ret;
490 }
491
492 static void handle_help_flag(struct lls_parse_result *lpr)
493 {
494 char *help;
495
496 if (CLIENT_OPT_GIVEN(DETAILED_HELP, lpr))
497 help = lls_long_help(CLIENT_CMD_PTR);
498 else if (CLIENT_OPT_GIVEN(HELP, lpr))
499 help = lls_short_help(CLIENT_CMD_PTR);
500 else
501 return;
502 printf("%s\n", help);
503 free(help);
504 exit(EXIT_SUCCESS);
505 }
506
507 /**
508 * Parse a client configuration.
509 *
510 * \param argc Usual argument count.
511 * \param argv Usual argument vector.
512 * \param ct_ptr Filled in by this function.
513 * \param loglevel If not \p NULL, the number of the loglevel is stored here.
514 *
515 * This checks the command line options given by \a argc and \a argv, sets
516 * default values for the user name and the name of the rsa key file and reads
517 * further options from the config file.
518 *
519 * Upon successful return, \a ct_ptr points to a dynamically allocated and
520 * initialized client task struct.
521 *
522 * \return The number of non-option arguments in \a argc/argv on success,
523 * negative on errors.
524 */
525 int client_parse_config(int argc, char *argv[], struct client_task **ct_ptr,
526 int *loglevel)
527 {
528 const struct lls_command *cmd = CLIENT_CMD_PTR;
529 struct lls_parse_result *lpr;
530 int ret, ll;
531 struct client_task *ct;
532 char *kf = NULL, *user, *errctx, *home = para_homedir();
533
534 ret = lls(lls_parse(argc, argv, cmd, &lpr, &errctx));
535 if (ret < 0)
536 goto out;
537 version_handle_flag("client", CLIENT_OPT_GIVEN(VERSION, lpr));
538 handle_help_flag(lpr);
539
540 ret = lsu_merge_config_file_options(CLIENT_OPT_STRING_VAL(CONFIG_FILE, lpr),
541 "client.conf", &lpr, cmd, client_suite, 0U /* default flags */);
542 if (ret < 0)
543 goto out;
544 /* success */
545 ll = CLIENT_OPT_UINT32_VAL(LOGLEVEL, lpr);
546 if (loglevel)
547 *loglevel = ll;
548 user = CLIENT_OPT_GIVEN(USER, lpr)?
549 para_strdup(CLIENT_OPT_STRING_VAL(USER, lpr)) : para_logname();
550
551 if (CLIENT_OPT_GIVEN(KEY_FILE, lpr))
552 kf = para_strdup(CLIENT_OPT_STRING_VAL(KEY_FILE, lpr));
553 else {
554 kf = make_message("%s/.paraslash/key.%s", home, user);
555 if (!file_exists(kf)) {
556 free(kf);
557 kf = make_message("%s/.ssh/id_rsa", home);
558 }
559 }
560 PARA_INFO_LOG("user: %s\n", user);
561 PARA_INFO_LOG("key file: %s\n", kf);
562 PARA_INFO_LOG("loglevel: %d\n", ll);
563 ct = para_calloc(sizeof(*ct));
564 ct->scc.fd = -1;
565 ct->lpr = lpr;
566 ct->key_file = kf;
567 ct->user = user;
568 *ct_ptr = ct;
569 ret = lls_num_inputs(lpr);
570 out:
571 free(home);
572 if (ret < 0) {
573 if (errctx)
574 PARA_ERROR_LOG("%s\n", errctx);
575 free(errctx);
576 lls_free_parse_result(lpr, cmd);
577 free(kf);
578 *ct_ptr = NULL;
579 }
580 return ret;
581 }
582
583 /**
584 * Parse the client configuration and open a connection to para_server.
585 *
586 * \param argc See \ref client_parse_config.
587 * \param argv See \ref client_parse_config.
588 * \param ct_ptr See \ref client_parse_config.
589 * \param loglevel See \ref client_parse_config.
590 * \param parent See \ref client_connect().
591 * \param child See \ref client_connect().
592 * \param sched See \ref client_connect().
593 *
594 * This function combines client_parse_config() and client_connect(). It is
595 * considered a syntax error if no command was given, i.e. if the number
596 * of non-option arguments is zero.
597 *
598 * \return Standard.
599 */
600 int client_open(int argc, char *argv[], struct client_task **ct_ptr,
601 int *loglevel, struct btr_node *parent, struct btr_node *child,
602 struct sched *sched)
603 {
604 int ret = client_parse_config(argc, argv, ct_ptr, loglevel);
605
606 if (ret < 0)
607 return ret;
608 if (ret == 0) {
609 ret = -E_CLIENT_SYNTAX;
610 goto fail;
611 }
612 ret = client_connect(*ct_ptr, sched, parent, child);
613 if (ret < 0)
614 goto fail;
615 return 1;
616 fail:
617 client_close(*ct_ptr);
618 *ct_ptr = NULL;
619 return ret;
620 }