Allow some pre-/post-xfer exec shell restrictions.
[rsync.git] / main.c
1 /*
2  * The startup routines, including main(), for rsync.
3  *
4  * Copyright (C) 1996-2001 Andrew Tridgell <tridge@samba.org>
5  * Copyright (C) 1996 Paul Mackerras
6  * Copyright (C) 2001, 2002 Martin Pool <mbp@samba.org>
7  * Copyright (C) 2003-2018 Wayne Davison
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 3 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License along
20  * with this program; if not, visit the http://fsf.org website.
21  */
22
23 #include "rsync.h"
24 #include "inums.h"
25 #include "io.h"
26 #if defined CONFIG_LOCALE && defined HAVE_LOCALE_H
27 #include <locale.h>
28 #endif
29
30 extern int dry_run;
31 extern int list_only;
32 extern int io_timeout;
33 extern int am_root;
34 extern int am_server;
35 extern int am_sender;
36 extern int am_daemon;
37 extern int inc_recurse;
38 extern int blocking_io;
39 extern int always_checksum;
40 extern int remove_source_files;
41 extern int output_needs_newline;
42 extern int need_messages_from_generator;
43 extern int kluge_around_eof;
44 extern int got_xfer_error;
45 extern int msgs2stderr;
46 extern int module_id;
47 extern int read_only;
48 extern int copy_links;
49 extern int copy_dirlinks;
50 extern int copy_unsafe_links;
51 extern int keep_dirlinks;
52 extern int preserve_hard_links;
53 extern int protocol_version;
54 extern int file_total;
55 extern int recurse;
56 extern int xfer_dirs;
57 extern int protect_args;
58 extern int relative_paths;
59 extern int sanitize_paths;
60 extern int curr_dir_depth;
61 extern int curr_dir_len;
62 extern int module_id;
63 extern int rsync_port;
64 extern int whole_file;
65 extern int read_batch;
66 extern int write_batch;
67 extern int batch_fd;
68 extern int sock_f_in;
69 extern int sock_f_out;
70 extern int filesfrom_fd;
71 extern int connect_timeout;
72 extern int send_msgs_to_gen;
73 extern dev_t filesystem_dev;
74 extern pid_t cleanup_child_pid;
75 extern size_t bwlimit_writemax;
76 extern unsigned int module_dirlen;
77 extern BOOL flist_receiving_enabled;
78 extern BOOL shutting_down;
79 extern int backup_dir_len;
80 extern int basis_dir_cnt;
81 extern struct stats stats;
82 extern char *stdout_format;
83 extern char *logfile_format;
84 extern char *filesfrom_host;
85 extern char *partial_dir;
86 extern char *dest_option;
87 extern char *rsync_path;
88 extern char *shell_cmd;
89 extern char *batch_name;
90 extern char *password_file;
91 extern char *backup_dir;
92 extern char curr_dir[MAXPATHLEN];
93 extern char backup_dir_buf[MAXPATHLEN];
94 extern char *basis_dir[MAX_BASIS_DIRS+1];
95 extern struct file_list *first_flist;
96 extern filter_rule_list daemon_filter_list;
97
98 uid_t our_uid;
99 gid_t our_gid;
100 int am_receiver = 0;  /* Only set to 1 after the receiver/generator fork. */
101 int am_generator = 0; /* Only set to 1 after the receiver/generator fork. */
102 int local_server = 0;
103 int daemon_over_rsh = 0;
104 mode_t orig_umask = 0;
105 int batch_gen_fd = -1;
106 int sender_keeps_checksum = 0;
107
108 /* There's probably never more than at most 2 outstanding child processes,
109  * but set it higher, just in case. */
110 #define MAXCHILDPROCS 7
111
112 #ifdef HAVE_SIGACTION
113 # ifdef HAVE_SIGPROCMASK
114 #  define SIGACTMASK(n,h) SIGACTION(n,h), sigaddset(&sigmask,(n))
115 # else
116 #  define SIGACTMASK(n,h) SIGACTION(n,h)
117 # endif
118 static struct sigaction sigact;
119 #endif
120
121 struct pid_status {
122         pid_t pid;
123         int status;
124 } pid_stat_table[MAXCHILDPROCS];
125
126 static time_t starttime, endtime;
127 static int64 total_read, total_written;
128
129 static void show_malloc_stats(void);
130
131 /* Works like waitpid(), but if we already harvested the child pid in our
132  * remember_children(), we succeed instead of returning an error. */
133 pid_t wait_process(pid_t pid, int *status_ptr, int flags)
134 {
135         pid_t waited_pid;
136
137         do {
138                 waited_pid = waitpid(pid, status_ptr, flags);
139         } while (waited_pid == -1 && errno == EINTR);
140
141         if (waited_pid == -1 && errno == ECHILD) {
142                 /* Status of requested child no longer available:  check to
143                  * see if it was processed by remember_children(). */
144                 int cnt;
145                 for (cnt = 0; cnt < MAXCHILDPROCS; cnt++) {
146                         if (pid == pid_stat_table[cnt].pid) {
147                                 *status_ptr = pid_stat_table[cnt].status;
148                                 pid_stat_table[cnt].pid = 0;
149                                 return pid;
150                         }
151                 }
152         }
153
154         return waited_pid;
155 }
156
157 int shell_exec(const char *cmd)
158 {
159         char *shell = getenv("RSYNC_SHELL");
160         int status;
161         pid_t pid;
162
163         if (!shell)
164                 return system(cmd);
165
166         if ((pid = fork()) < 0)
167                 return -1;
168
169         if (pid == 0) {
170                 execlp(shell, shell, "-c", cmd, NULL);
171                 _exit(1);
172         }
173
174         int ret = wait_process(pid, &status, 0);
175         return ret < 0 ? -1 : status;
176 }
177
178 /* Wait for a process to exit, calling io_flush while waiting. */
179 static void wait_process_with_flush(pid_t pid, int *exit_code_ptr)
180 {
181         pid_t waited_pid;
182         int status;
183
184         while ((waited_pid = wait_process(pid, &status, WNOHANG)) == 0) {
185                 msleep(20);
186                 io_flush(FULL_FLUSH);
187         }
188
189         /* TODO: If the child exited on a signal, then log an
190          * appropriate error message.  Perhaps we should also accept a
191          * message describing the purpose of the child.  Also indicate
192          * this to the caller so that they know something went wrong. */
193         if (waited_pid < 0) {
194                 rsyserr(FERROR, errno, "waitpid");
195                 *exit_code_ptr = RERR_WAITCHILD;
196         } else if (!WIFEXITED(status)) {
197 #ifdef WCOREDUMP
198                 if (WCOREDUMP(status))
199                         *exit_code_ptr = RERR_CRASHED;
200                 else
201 #endif
202                 if (WIFSIGNALED(status))
203                         *exit_code_ptr = RERR_TERMINATED;
204                 else
205                         *exit_code_ptr = RERR_WAITCHILD;
206         } else
207                 *exit_code_ptr = WEXITSTATUS(status);
208 }
209
210 void write_del_stats(int f)
211 {
212         if (read_batch)
213                 write_int(f, NDX_DEL_STATS);
214         else
215                 write_ndx(f, NDX_DEL_STATS);
216         write_varint(f, stats.deleted_files - stats.deleted_dirs
217                       - stats.deleted_symlinks - stats.deleted_devices
218                       - stats.deleted_specials);
219         write_varint(f, stats.deleted_dirs);
220         write_varint(f, stats.deleted_symlinks);
221         write_varint(f, stats.deleted_devices);
222         write_varint(f, stats.deleted_specials);
223 }
224
225 void read_del_stats(int f)
226 {
227         stats.deleted_files = read_varint(f);
228         stats.deleted_files += stats.deleted_dirs = read_varint(f);
229         stats.deleted_files += stats.deleted_symlinks = read_varint(f);
230         stats.deleted_files += stats.deleted_devices = read_varint(f);
231         stats.deleted_files += stats.deleted_specials = read_varint(f);
232 }
233
234 /* This function gets called from all 3 processes.  We want the client side
235  * to actually output the text, but the sender is the only process that has
236  * all the stats we need.  So, if we're a client sender, we do the report.
237  * If we're a server sender, we write the stats on the supplied fd.  If
238  * we're the client receiver we read the stats from the supplied fd and do
239  * the report.  All processes might also generate a set of debug stats, if
240  * the verbose level is high enough (this is the only thing that the
241  * generator process and the server receiver ever do here). */
242 static void handle_stats(int f)
243 {
244         endtime = time(NULL);
245
246         /* Cache two stats because the read/write code can change it. */
247         total_read = stats.total_read;
248         total_written = stats.total_written;
249
250         if (INFO_GTE(STATS, 3)) {
251                 /* These come out from every process */
252                 show_malloc_stats();
253                 show_flist_stats();
254         }
255
256         if (am_generator)
257                 return;
258
259         if (am_daemon) {
260                 if (f == -1 || !am_sender)
261                         return;
262         }
263
264         if (am_server) {
265                 if (am_sender) {
266                         write_varlong30(f, total_read, 3);
267                         write_varlong30(f, total_written, 3);
268                         write_varlong30(f, stats.total_size, 3);
269                         if (protocol_version >= 29) {
270                                 write_varlong30(f, stats.flist_buildtime, 3);
271                                 write_varlong30(f, stats.flist_xfertime, 3);
272                         }
273                 }
274                 return;
275         }
276
277         /* this is the client */
278
279         if (f < 0 && !am_sender) /* e.g. when we got an empty file list. */
280                 ;
281         else if (!am_sender) {
282                 /* Read the first two in opposite order because the meaning of
283                  * read/write swaps when switching from sender to receiver. */
284                 total_written = read_varlong30(f, 3);
285                 total_read = read_varlong30(f, 3);
286                 stats.total_size = read_varlong30(f, 3);
287                 if (protocol_version >= 29) {
288                         stats.flist_buildtime = read_varlong30(f, 3);
289                         stats.flist_xfertime = read_varlong30(f, 3);
290                 }
291         } else if (write_batch) {
292                 /* The --read-batch process is going to be a client
293                  * receiver, so we need to give it the stats. */
294                 write_varlong30(batch_fd, total_read, 3);
295                 write_varlong30(batch_fd, total_written, 3);
296                 write_varlong30(batch_fd, stats.total_size, 3);
297                 if (protocol_version >= 29) {
298                         write_varlong30(batch_fd, stats.flist_buildtime, 3);
299                         write_varlong30(batch_fd, stats.flist_xfertime, 3);
300                 }
301         }
302 }
303
304 static void output_itemized_counts(const char *prefix, int *counts)
305 {
306         static char *labels[] = { "reg", "dir", "link", "dev", "special" };
307         char buf[1024], *pre = " (";
308         int j, len = 0;
309         int total = counts[0];
310         if (total) {
311                 counts[0] -= counts[1] + counts[2] + counts[3] + counts[4];
312                 for (j = 0; j < 5; j++) {
313                         if (counts[j]) {
314                                 len += snprintf(buf+len, sizeof buf - len - 2,
315                                         "%s%s: %s",
316                                         pre, labels[j], comma_num(counts[j]));
317                                 pre = ", ";
318                         }
319                 }
320                 buf[len++] = ')';
321         }
322         buf[len] = '\0';
323         rprintf(FINFO, "%s: %s%s\n", prefix, comma_num(total), buf);
324 }
325
326 static const char *bytes_per_sec_human_dnum(void)
327 {
328         if (starttime == (time_t)-1 || endtime == (time_t)-1)
329                 return "UNKNOWN";
330         return human_dnum((total_written + total_read) / (0.5 + (endtime - starttime)), 2);
331 }
332
333 static void output_summary(void)
334 {
335         if (INFO_GTE(STATS, 2)) {
336                 rprintf(FCLIENT, "\n");
337                 output_itemized_counts("Number of files", &stats.num_files);
338                 if (protocol_version >= 29)
339                         output_itemized_counts("Number of created files", &stats.created_files);
340                 if (protocol_version >= 31)
341                         output_itemized_counts("Number of deleted files", &stats.deleted_files);
342                 rprintf(FINFO,"Number of regular files transferred: %s\n",
343                         comma_num(stats.xferred_files));
344                 rprintf(FINFO,"Total file size: %s bytes\n",
345                         human_num(stats.total_size));
346                 rprintf(FINFO,"Total transferred file size: %s bytes\n",
347                         human_num(stats.total_transferred_size));
348                 rprintf(FINFO,"Literal data: %s bytes\n",
349                         human_num(stats.literal_data));
350                 rprintf(FINFO,"Matched data: %s bytes\n",
351                         human_num(stats.matched_data));
352                 rprintf(FINFO,"File list size: %s\n",
353                         human_num(stats.flist_size));
354                 if (stats.flist_buildtime) {
355                         rprintf(FINFO,
356                                 "File list generation time: %s seconds\n",
357                                 comma_dnum((double)stats.flist_buildtime / 1000, 3));
358                         rprintf(FINFO,
359                                 "File list transfer time: %s seconds\n",
360                                 comma_dnum((double)stats.flist_xfertime / 1000, 3));
361                 }
362                 rprintf(FINFO,"Total bytes sent: %s\n",
363                         human_num(total_written));
364                 rprintf(FINFO,"Total bytes received: %s\n",
365                         human_num(total_read));
366         }
367
368         if (INFO_GTE(STATS, 1)) {
369                 rprintf(FCLIENT, "\n");
370                 rprintf(FINFO,
371                         "sent %s bytes  received %s bytes  %s bytes/sec\n",
372                         human_num(total_written), human_num(total_read),
373                         bytes_per_sec_human_dnum());
374                 rprintf(FINFO, "total size is %s  speedup is %s%s\n",
375                         human_num(stats.total_size),
376                         comma_dnum((double)stats.total_size / (total_written+total_read), 2),
377                         write_batch < 0 ? " (BATCH ONLY)" : dry_run ? " (DRY RUN)" : "");
378         }
379
380         fflush(stdout);
381         fflush(stderr);
382 }
383
384
385 /**
386  * If our C library can get malloc statistics, then show them to FINFO
387  **/
388 static void show_malloc_stats(void)
389 {
390 #ifdef HAVE_MALLINFO
391         struct mallinfo mi;
392
393         mi = mallinfo();
394
395         rprintf(FCLIENT, "\n");
396         rprintf(FINFO, RSYNC_NAME "[%d] (%s%s%s) heap statistics:\n",
397                 (int)getpid(), am_server ? "server " : "",
398                 am_daemon ? "daemon " : "", who_am_i());
399         rprintf(FINFO, "  arena:     %10ld   (bytes from sbrk)\n",
400                 (long)mi.arena);
401         rprintf(FINFO, "  ordblks:   %10ld   (chunks not in use)\n",
402                 (long)mi.ordblks);
403         rprintf(FINFO, "  smblks:    %10ld\n",
404                 (long)mi.smblks);
405         rprintf(FINFO, "  hblks:     %10ld   (chunks from mmap)\n",
406                 (long)mi.hblks);
407         rprintf(FINFO, "  hblkhd:    %10ld   (bytes from mmap)\n",
408                 (long)mi.hblkhd);
409         rprintf(FINFO, "  allmem:    %10ld   (bytes from sbrk + mmap)\n",
410                 (long)mi.arena + mi.hblkhd);
411         rprintf(FINFO, "  usmblks:   %10ld\n",
412                 (long)mi.usmblks);
413         rprintf(FINFO, "  fsmblks:   %10ld\n",
414                 (long)mi.fsmblks);
415         rprintf(FINFO, "  uordblks:  %10ld   (bytes used)\n",
416                 (long)mi.uordblks);
417         rprintf(FINFO, "  fordblks:  %10ld   (bytes free)\n",
418                 (long)mi.fordblks);
419         rprintf(FINFO, "  keepcost:  %10ld   (bytes in releasable chunk)\n",
420                 (long)mi.keepcost);
421 #endif /* HAVE_MALLINFO */
422 }
423
424
425 /* Start the remote shell.   cmd may be NULL to use the default. */
426 static pid_t do_cmd(char *cmd, char *machine, char *user, char **remote_argv, int remote_argc,
427                     int *f_in_p, int *f_out_p)
428 {
429         int i, argc = 0;
430         char *args[MAX_ARGS], *need_to_free = NULL;
431         pid_t pid;
432         int dash_l_set = 0;
433
434         if (!read_batch && !local_server) {
435                 char *t, *f, in_quote = '\0';
436                 char *rsh_env = getenv(RSYNC_RSH_ENV);
437                 if (!cmd)
438                         cmd = rsh_env;
439                 if (!cmd)
440                         cmd = RSYNC_RSH;
441                 cmd = need_to_free = strdup(cmd);
442                 if (!cmd)
443                         goto oom;
444
445                 for (t = f = cmd; *f; f++) {
446                         if (*f == ' ')
447                                 continue;
448                         /* Comparison leaves rooms for server_options(). */
449                         if (argc >= MAX_ARGS - MAX_SERVER_ARGS)
450                                 goto arg_overflow;
451                         args[argc++] = t;
452                         while (*f != ' ' || in_quote) {
453                                 if (!*f) {
454                                         if (in_quote) {
455                                                 rprintf(FERROR,
456                                                     "Missing trailing-%c in remote-shell command.\n",
457                                                     in_quote);
458                                                 exit_cleanup(RERR_SYNTAX);
459                                         }
460                                         f--;
461                                         break;
462                                 }
463                                 if (*f == '\'' || *f == '"') {
464                                         if (!in_quote) {
465                                                 in_quote = *f++;
466                                                 continue;
467                                         }
468                                         if (*f == in_quote && *++f != in_quote) {
469                                                 in_quote = '\0';
470                                                 continue;
471                                         }
472                                 }
473                                 *t++ = *f++;
474                         }
475                         *t++ = '\0';
476                 }
477
478                 /* check to see if we've already been given '-l user' in
479                  * the remote-shell command */
480                 for (i = 0; i < argc-1; i++) {
481                         if (!strcmp(args[i], "-l") && args[i+1][0] != '-')
482                                 dash_l_set = 1;
483                 }
484
485 #ifdef HAVE_REMSH
486                 /* remsh (on HPUX) takes the arguments the other way around */
487                 args[argc++] = machine;
488                 if (user && !(daemon_over_rsh && dash_l_set)) {
489                         args[argc++] = "-l";
490                         args[argc++] = user;
491                 }
492 #else
493                 if (user && !(daemon_over_rsh && dash_l_set)) {
494                         args[argc++] = "-l";
495                         args[argc++] = user;
496                 }
497                 args[argc++] = machine;
498 #endif
499
500                 args[argc++] = rsync_path;
501
502                 if (blocking_io < 0) {
503                         char *cp;
504                         if ((cp = strrchr(cmd, '/')) != NULL)
505                                 cp++;
506                         else
507                                 cp = cmd;
508                         if (strcmp(cp, "rsh") == 0 || strcmp(cp, "remsh") == 0)
509                                 blocking_io = 1;
510                 }
511
512                 server_options(args,&argc);
513
514                 if (argc >= MAX_ARGS - 2)
515                         goto arg_overflow;
516         }
517
518         args[argc++] = ".";
519
520         if (!daemon_over_rsh) {
521                 while (remote_argc > 0) {
522                         if (argc >= MAX_ARGS - 1) {
523                           arg_overflow:
524                                 rprintf(FERROR, "internal: args[] overflowed in do_cmd()\n");
525                                 exit_cleanup(RERR_SYNTAX);
526                         }
527                         if (**remote_argv == '-') {
528                                 if (asprintf(args + argc++, "./%s", *remote_argv++) < 0)
529                                         out_of_memory("do_cmd");
530                         } else
531                                 args[argc++] = *remote_argv++;
532                         remote_argc--;
533                 }
534         }
535
536         args[argc] = NULL;
537
538         if (DEBUG_GTE(CMD, 2)) {
539                 for (i = 0; i < argc; i++)
540                         rprintf(FCLIENT, "cmd[%d]=%s ", i, args[i]);
541                 rprintf(FCLIENT, "\n");
542         }
543
544         if (read_batch) {
545                 int from_gen_pipe[2];
546                 set_allow_inc_recurse();
547                 if (fd_pair(from_gen_pipe) < 0) {
548                         rsyserr(FERROR, errno, "pipe");
549                         exit_cleanup(RERR_IPC);
550                 }
551                 batch_gen_fd = from_gen_pipe[0];
552                 *f_out_p = from_gen_pipe[1];
553                 *f_in_p = batch_fd;
554                 pid = (pid_t)-1; /* no child pid */
555 #ifdef ICONV_CONST
556                 setup_iconv();
557 #endif
558         } else if (local_server) {
559                 /* If the user didn't request --[no-]whole-file, force
560                  * it on, but only if we're not batch processing. */
561                 if (whole_file < 0 && !write_batch)
562                         whole_file = 1;
563                 set_allow_inc_recurse();
564                 pid = local_child(argc, args, f_in_p, f_out_p, child_main);
565 #ifdef ICONV_CONST
566                 setup_iconv();
567 #endif
568         } else {
569                 pid = piped_child(args, f_in_p, f_out_p);
570 #ifdef ICONV_CONST
571                 setup_iconv();
572 #endif
573                 if (protect_args && !daemon_over_rsh)
574                         send_protected_args(*f_out_p, args);
575         }
576
577         if (need_to_free)
578                 free(need_to_free);
579
580         return pid;
581
582   oom:
583         out_of_memory("do_cmd");
584         return 0; /* not reached */
585 }
586
587 /* The receiving side operates in one of two modes:
588  *
589  * 1. it receives any number of files into a destination directory,
590  * placing them according to their names in the file-list.
591  *
592  * 2. it receives a single file and saves it using the name in the
593  * destination path instead of its file-list name.  This requires a
594  * "local name" for writing out the destination file.
595  *
596  * So, our task is to figure out what mode/local-name we need.
597  * For mode 1, we change into the destination directory and return NULL.
598  * For mode 2, we change into the directory containing the destination
599  * file (if we aren't already there) and return the local-name. */
600 static char *get_local_name(struct file_list *flist, char *dest_path)
601 {
602         STRUCT_STAT st;
603         int statret;
604         char *cp;
605
606         if (DEBUG_GTE(RECV, 1)) {
607                 rprintf(FINFO, "get_local_name count=%d %s\n",
608                         file_total, NS(dest_path));
609         }
610
611         if (!dest_path || list_only)
612                 return NULL;
613
614         /* Treat an empty string as a copy into the current directory. */
615         if (!*dest_path)
616             dest_path = ".";
617
618         if (daemon_filter_list.head) {
619                 char *slash = strrchr(dest_path, '/');
620                 if (slash && (slash[1] == '\0' || (slash[1] == '.' && slash[2] == '\0')))
621                         *slash = '\0';
622                 else
623                         slash = NULL;
624                 if ((*dest_path != '.' || dest_path[1] != '\0')
625                  && (check_filter(&daemon_filter_list, FLOG, dest_path, 0) < 0
626                   || check_filter(&daemon_filter_list, FLOG, dest_path, 1) < 0)) {
627                         rprintf(FERROR, "ERROR: daemon has excluded destination \"%s\"\n",
628                                 dest_path);
629                         exit_cleanup(RERR_FILESELECT);
630                 }
631                 if (slash)
632                         *slash = '/';
633         }
634
635         /* See what currently exists at the destination. */
636         if ((statret = do_stat(dest_path, &st)) == 0) {
637                 /* If the destination is a dir, enter it and use mode 1. */
638                 if (S_ISDIR(st.st_mode)) {
639                         if (!change_dir(dest_path, CD_NORMAL)) {
640                                 rsyserr(FERROR, errno, "change_dir#1 %s failed",
641                                         full_fname(dest_path));
642                                 exit_cleanup(RERR_FILESELECT);
643                         }
644                         filesystem_dev = st.st_dev; /* ensures --force works right w/-x */
645                         return NULL;
646                 }
647                 if (file_total > 1) {
648                         rprintf(FERROR,
649                                 "ERROR: destination must be a directory when"
650                                 " copying more than 1 file\n");
651                         exit_cleanup(RERR_FILESELECT);
652                 }
653                 if (file_total == 1 && S_ISDIR(flist->files[0]->mode)) {
654                         rprintf(FERROR,
655                                 "ERROR: cannot overwrite non-directory"
656                                 " with a directory\n");
657                         exit_cleanup(RERR_FILESELECT);
658                 }
659         } else if (errno != ENOENT) {
660                 /* If we don't know what's at the destination, fail. */
661                 rsyserr(FERROR, errno, "ERROR: cannot stat destination %s",
662                         full_fname(dest_path));
663                 exit_cleanup(RERR_FILESELECT);
664         }
665
666         cp = strrchr(dest_path, '/');
667
668         /* If we need a destination directory because the transfer is not
669          * of a single non-directory or the user has requested one via a
670          * destination path ending in a slash, create one and use mode 1. */
671         if (file_total > 1 || (cp && !cp[1])) {
672                 /* Lop off the final slash (if any). */
673                 if (cp && !cp[1])
674                         *cp = '\0';
675
676                 if (statret == 0) {
677                         rprintf(FERROR,
678                             "ERROR: destination path is not a directory\n");
679                         exit_cleanup(RERR_SYNTAX);
680                 }
681
682                 if (do_mkdir(dest_path, ACCESSPERMS) != 0) {
683                         rsyserr(FERROR, errno, "mkdir %s failed",
684                                 full_fname(dest_path));
685                         exit_cleanup(RERR_FILEIO);
686                 }
687
688                 if (flist->high >= flist->low
689                  && strcmp(flist->files[flist->low]->basename, ".") == 0)
690                         flist->files[0]->flags |= FLAG_DIR_CREATED;
691
692                 if (INFO_GTE(NAME, 1))
693                         rprintf(FINFO, "created directory %s\n", dest_path);
694
695                 if (dry_run) {
696                         /* Indicate that dest dir doesn't really exist. */
697                         dry_run++;
698                 }
699
700                 if (!change_dir(dest_path, dry_run > 1 ? CD_SKIP_CHDIR : CD_NORMAL)) {
701                         rsyserr(FERROR, errno, "change_dir#2 %s failed",
702                                 full_fname(dest_path));
703                         exit_cleanup(RERR_FILESELECT);
704                 }
705
706                 return NULL;
707         }
708
709         /* Otherwise, we are writing a single file, possibly on top of an
710          * existing non-directory.  Change to the item's parent directory
711          * (if it has a path component), return the basename of the
712          * destination file as the local name, and use mode 2. */
713         if (!cp)
714                 return dest_path;
715
716         if (cp == dest_path)
717                 dest_path = "/";
718
719         *cp = '\0';
720         if (!change_dir(dest_path, CD_NORMAL)) {
721                 rsyserr(FERROR, errno, "change_dir#3 %s failed",
722                         full_fname(dest_path));
723                 exit_cleanup(RERR_FILESELECT);
724         }
725         *cp = '/';
726
727         return cp + 1;
728 }
729
730 /* This function checks on our alternate-basis directories.  If we're in
731  * dry-run mode and the destination dir does not yet exist, we'll try to
732  * tweak any dest-relative paths to make them work for a dry-run (the
733  * destination dir must be in curr_dir[] when this function is called).
734  * We also warn about any arg that is non-existent or not a directory. */
735 static void check_alt_basis_dirs(void)
736 {
737         STRUCT_STAT st;
738         char *slash = strrchr(curr_dir, '/');
739         int j;
740
741         for (j = 0; j < basis_dir_cnt; j++) {
742                 char *bdir = basis_dir[j];
743                 int bd_len = strlen(bdir);
744                 if (bd_len > 1 && bdir[bd_len-1] == '/')
745                         bdir[--bd_len] = '\0';
746                 if (dry_run > 1 && *bdir != '/') {
747                         int len = curr_dir_len + 1 + bd_len + 1;
748                         char *new = new_array(char, len);
749                         if (!new)
750                                 out_of_memory("check_alt_basis_dirs");
751                         if (slash && strncmp(bdir, "../", 3) == 0) {
752                             /* We want to remove only one leading "../" prefix for
753                              * the directory we couldn't create in dry-run mode:
754                              * this ensures that any other ".." references get
755                              * evaluated the same as they would for a live copy. */
756                             *slash = '\0';
757                             pathjoin(new, len, curr_dir, bdir + 3);
758                             *slash = '/';
759                         } else
760                             pathjoin(new, len, curr_dir, bdir);
761                         basis_dir[j] = bdir = new;
762                 }
763                 if (do_stat(bdir, &st) < 0)
764                         rprintf(FWARNING, "%s arg does not exist: %s\n", dest_option, bdir);
765                 else if (!S_ISDIR(st.st_mode))
766                         rprintf(FWARNING, "%s arg is not a dir: %s\n", dest_option, bdir);
767         }
768 }
769
770 /* This is only called by the sender. */
771 static void read_final_goodbye(int f_in, int f_out)
772 {
773         int i, iflags, xlen;
774         uchar fnamecmp_type;
775         char xname[MAXPATHLEN];
776
777         shutting_down = True;
778
779         if (protocol_version < 29)
780                 i = read_int(f_in);
781         else {
782                 i = read_ndx_and_attrs(f_in, f_out, &iflags, &fnamecmp_type, xname, &xlen);
783                 if (protocol_version >= 31 && i == NDX_DONE) {
784                         if (am_sender)
785                                 write_ndx(f_out, NDX_DONE);
786                         else {
787                                 if (batch_gen_fd >= 0) {
788                                         while (read_int(batch_gen_fd) != NDX_DEL_STATS) {}
789                                         read_del_stats(batch_gen_fd);
790                                 }
791                                 write_int(f_out, NDX_DONE);
792                         }
793                         i = read_ndx_and_attrs(f_in, f_out, &iflags, &fnamecmp_type, xname, &xlen);
794                 }
795         }
796
797         if (i != NDX_DONE) {
798                 rprintf(FERROR, "Invalid packet at end of run (%d) [%s]\n",
799                         i, who_am_i());
800                 exit_cleanup(RERR_PROTOCOL);
801         }
802 }
803
804 static void do_server_sender(int f_in, int f_out, int argc, char *argv[])
805 {
806         struct file_list *flist;
807         char *dir;
808
809         if (DEBUG_GTE(SEND, 1))
810                 rprintf(FINFO, "server_sender starting pid=%d\n", (int)getpid());
811
812         if (am_daemon && lp_write_only(module_id)) {
813                 rprintf(FERROR, "ERROR: module is write only\n");
814                 exit_cleanup(RERR_SYNTAX);
815         }
816         if (am_daemon && read_only && remove_source_files) {
817                 rprintf(FERROR,
818                         "ERROR: --remove-%s-files cannot be used with a read-only module\n",
819                         remove_source_files == 1 ? "source" : "sent");
820                 exit_cleanup(RERR_SYNTAX);
821         }
822         if (argc < 1) {
823                 rprintf(FERROR, "ERROR: do_server_sender called without args\n");
824                 exit_cleanup(RERR_SYNTAX);
825         }
826
827         dir = argv[0];
828         if (!relative_paths) {
829                 if (!change_dir(dir, CD_NORMAL)) {
830                         rsyserr(FERROR, errno, "change_dir#3 %s failed",
831                                 full_fname(dir));
832                         exit_cleanup(RERR_FILESELECT);
833                 }
834         }
835         argc--;
836         argv++;
837
838         if (argc == 0 && (recurse || xfer_dirs || list_only)) {
839                 argc = 1;
840                 argv--;
841                 argv[0] = ".";
842         }
843
844         flist = send_file_list(f_out,argc,argv);
845         if (!flist || flist->used == 0) {
846                 /* Make sure input buffering is off so we can't hang in noop_io_until_death(). */
847                 io_end_buffering_in(0);
848                 /* TODO:  we should really exit in a more controlled manner. */
849                 exit_cleanup(0);
850         }
851
852         io_start_buffering_in(f_in);
853
854         send_files(f_in, f_out);
855         io_flush(FULL_FLUSH);
856         handle_stats(f_out);
857         if (protocol_version >= 24)
858                 read_final_goodbye(f_in, f_out);
859         io_flush(FULL_FLUSH);
860         exit_cleanup(0);
861 }
862
863
864 static int do_recv(int f_in, int f_out, char *local_name)
865 {
866         int pid;
867         int exit_code = 0;
868         int error_pipe[2];
869
870         /* The receiving side mustn't obey this, or an existing symlink that
871          * points to an identical file won't be replaced by the referent. */
872         copy_links = copy_dirlinks = copy_unsafe_links = 0;
873
874 #ifdef SUPPORT_HARD_LINKS
875         if (preserve_hard_links && !inc_recurse)
876                 match_hard_links(first_flist);
877 #endif
878
879         if (fd_pair(error_pipe) < 0) {
880                 rsyserr(FERROR, errno, "pipe failed in do_recv");
881                 exit_cleanup(RERR_IPC);
882         }
883
884         if (backup_dir) {
885                 STRUCT_STAT st;
886                 int ret;
887                 if (backup_dir_len > 1)
888                         backup_dir_buf[backup_dir_len-1] = '\0';
889                 ret = do_stat(backup_dir_buf, &st);
890                 if (ret != 0 || !S_ISDIR(st.st_mode)) {
891                         if (ret == 0) {
892                                 rprintf(FERROR, "The backup-dir is not a directory: %s\n", backup_dir_buf);
893                                 exit_cleanup(RERR_SYNTAX);
894                         }
895                         if (errno != ENOENT) {
896                                 rprintf(FERROR, "Failed to stat %s: %s\n", backup_dir_buf, strerror(errno));
897                                 exit_cleanup(RERR_FILEIO);
898                         }
899                         if (INFO_GTE(BACKUP, 1))
900                                 rprintf(FINFO, "(new) backup_dir is %s\n", backup_dir_buf);
901                 } else if (INFO_GTE(BACKUP, 1))
902                         rprintf(FINFO, "backup_dir is %s\n", backup_dir_buf);
903                 if (backup_dir_len > 1)
904                         backup_dir_buf[backup_dir_len-1] = '/';
905         }
906
907         io_flush(FULL_FLUSH);
908
909         if ((pid = do_fork()) == -1) {
910                 rsyserr(FERROR, errno, "fork failed in do_recv");
911                 exit_cleanup(RERR_IPC);
912         }
913
914         if (pid == 0) {
915                 am_receiver = 1;
916                 send_msgs_to_gen = am_server;
917
918                 close(error_pipe[0]);
919
920                 /* We can't let two processes write to the socket at one time. */
921                 io_end_multiplex_out(MPLX_SWITCHING);
922                 if (f_in != f_out)
923                         close(f_out);
924                 sock_f_out = -1;
925                 f_out = error_pipe[1];
926
927                 bwlimit_writemax = 0; /* receiver doesn't need to do this */
928
929                 if (read_batch)
930                         io_start_buffering_in(f_in);
931                 io_start_multiplex_out(f_out);
932
933                 recv_files(f_in, f_out, local_name);
934                 io_flush(FULL_FLUSH);
935                 handle_stats(f_in);
936
937                 if (output_needs_newline) {
938                         fputc('\n', stdout);
939                         output_needs_newline = 0;
940                 }
941
942                 write_int(f_out, NDX_DONE);
943                 send_msg(MSG_STATS, (char*)&stats.total_read, sizeof stats.total_read, 0);
944                 io_flush(FULL_FLUSH);
945
946                 /* Handle any keep-alive packets from the post-processing work
947                  * that the generator does. */
948                 if (protocol_version >= 29) {
949                         kluge_around_eof = -1;
950
951                         /* This should only get stopped via a USR2 signal. */
952                         read_final_goodbye(f_in, f_out);
953
954                         rprintf(FERROR, "Invalid packet at end of run [%s]\n",
955                                 who_am_i());
956                         exit_cleanup(RERR_PROTOCOL);
957                 }
958
959                 /* Finally, we go to sleep until our parent kills us with a
960                  * USR2 signal.  We sleep for a short time, as on some OSes
961                  * a signal won't interrupt a sleep! */
962                 while (1)
963                         msleep(20);
964         }
965
966         am_generator = 1;
967         flist_receiving_enabled = True;
968
969         io_end_multiplex_in(MPLX_SWITCHING);
970         if (write_batch && !am_server)
971                 stop_write_batch();
972
973         close(error_pipe[1]);
974         if (f_in != f_out)
975                 close(f_in);
976         sock_f_in = -1;
977         f_in = error_pipe[0];
978
979         io_start_buffering_out(f_out);
980         io_start_multiplex_in(f_in);
981
982 #ifdef SUPPORT_HARD_LINKS
983         if (preserve_hard_links && inc_recurse) {
984                 struct file_list *flist;
985                 for (flist = first_flist; flist; flist = flist->next)
986                         match_hard_links(flist);
987         }
988 #endif
989
990         generate_files(f_out, local_name);
991
992         handle_stats(-1);
993         io_flush(FULL_FLUSH);
994         shutting_down = True;
995         if (protocol_version >= 24) {
996                 /* send a final goodbye message */
997                 write_ndx(f_out, NDX_DONE);
998         }
999         io_flush(FULL_FLUSH);
1000
1001         kill(pid, SIGUSR2);
1002         wait_process_with_flush(pid, &exit_code);
1003         return exit_code;
1004 }
1005
1006 static void do_server_recv(int f_in, int f_out, int argc, char *argv[])
1007 {
1008         int exit_code;
1009         struct file_list *flist;
1010         char *local_name = NULL;
1011         int negated_levels;
1012
1013         if (filesfrom_fd >= 0 && !msgs2stderr && protocol_version < 31) {
1014                 /* We can't mix messages with files-from data on the socket,
1015                  * so temporarily turn off info/debug messages. */
1016                 negate_output_levels();
1017                 negated_levels = 1;
1018         } else
1019                 negated_levels = 0;
1020
1021         if (DEBUG_GTE(RECV, 1))
1022                 rprintf(FINFO, "server_recv(%d) starting pid=%d\n", argc, (int)getpid());
1023
1024         if (am_daemon && read_only) {
1025                 rprintf(FERROR,"ERROR: module is read only\n");
1026                 exit_cleanup(RERR_SYNTAX);
1027                 return;
1028         }
1029
1030         if (argc > 0) {
1031                 char *dir = argv[0];
1032                 argc--;
1033                 argv++;
1034                 if (!am_daemon && !change_dir(dir, CD_NORMAL)) {
1035                         rsyserr(FERROR, errno, "change_dir#4 %s failed",
1036                                 full_fname(dir));
1037                         exit_cleanup(RERR_FILESELECT);
1038                 }
1039         }
1040
1041         if (protocol_version >= 30)
1042                 io_start_multiplex_in(f_in);
1043         else
1044                 io_start_buffering_in(f_in);
1045         recv_filter_list(f_in);
1046
1047         if (filesfrom_fd >= 0) {
1048                 /* We need to send the files-from names to the sender at the
1049                  * same time that we receive the file-list from them, so we
1050                  * need the IO routines to automatically write out the names
1051                  * onto our f_out socket as we read the file-list.  This
1052                  * avoids both deadlock and extra delays/buffers. */
1053                 start_filesfrom_forwarding(filesfrom_fd);
1054                 filesfrom_fd = -1;
1055         }
1056
1057         flist = recv_file_list(f_in, -1);
1058         if (!flist) {
1059                 rprintf(FERROR,"server_recv: recv_file_list error\n");
1060                 exit_cleanup(RERR_FILESELECT);
1061         }
1062         if (inc_recurse && file_total == 1)
1063                 recv_additional_file_list(f_in);
1064
1065         if (negated_levels)
1066                 negate_output_levels();
1067
1068         if (argc > 0)
1069                 local_name = get_local_name(flist,argv[0]);
1070
1071         /* Now that we know what our destination directory turned out to be,
1072          * we can sanitize the --link-/copy-/compare-dest args correctly. */
1073         if (sanitize_paths) {
1074                 char **dir_p;
1075                 for (dir_p = basis_dir; *dir_p; dir_p++)
1076                         *dir_p = sanitize_path(NULL, *dir_p, NULL, curr_dir_depth, SP_DEFAULT);
1077                 if (partial_dir)
1078                         partial_dir = sanitize_path(NULL, partial_dir, NULL, curr_dir_depth, SP_DEFAULT);
1079         }
1080         check_alt_basis_dirs();
1081
1082         if (daemon_filter_list.head) {
1083                 char **dir_p;
1084                 filter_rule_list *elp = &daemon_filter_list;
1085
1086                 for (dir_p = basis_dir; *dir_p; dir_p++) {
1087                         char *dir = *dir_p;
1088                         if (*dir == '/')
1089                                 dir += module_dirlen;
1090                         if (check_filter(elp, FLOG, dir, 1) < 0)
1091                                 goto options_rejected;
1092                 }
1093                 if (partial_dir && *partial_dir == '/'
1094                  && check_filter(elp, FLOG, partial_dir + module_dirlen, 1) < 0) {
1095                     options_rejected:
1096                         rprintf(FERROR,
1097                                 "Your options have been rejected by the server.\n");
1098                         exit_cleanup(RERR_SYNTAX);
1099                 }
1100         }
1101
1102         exit_code = do_recv(f_in, f_out, local_name);
1103         exit_cleanup(exit_code);
1104 }
1105
1106
1107 int child_main(int argc, char *argv[])
1108 {
1109         start_server(STDIN_FILENO, STDOUT_FILENO, argc, argv);
1110         return 0;
1111 }
1112
1113
1114 void start_server(int f_in, int f_out, int argc, char *argv[])
1115 {
1116         set_nonblocking(f_in);
1117         set_nonblocking(f_out);
1118
1119         io_set_sock_fds(f_in, f_out);
1120         setup_protocol(f_out, f_in);
1121
1122         if (protocol_version >= 23)
1123                 io_start_multiplex_out(f_out);
1124         if (am_daemon && io_timeout && protocol_version >= 31)
1125                 send_msg_int(MSG_IO_TIMEOUT, io_timeout);
1126
1127         if (am_sender) {
1128                 keep_dirlinks = 0; /* Must be disabled on the sender. */
1129                 if (need_messages_from_generator)
1130                         io_start_multiplex_in(f_in);
1131                 else
1132                         io_start_buffering_in(f_in);
1133                 recv_filter_list(f_in);
1134                 do_server_sender(f_in, f_out, argc, argv);
1135         } else
1136                 do_server_recv(f_in, f_out, argc, argv);
1137         exit_cleanup(0);
1138 }
1139
1140 /* This is called once the connection has been negotiated.  It is used
1141  * for rsyncd, remote-shell, and local connections. */
1142 int client_run(int f_in, int f_out, pid_t pid, int argc, char *argv[])
1143 {
1144         struct file_list *flist = NULL;
1145         int exit_code = 0, exit_code2 = 0;
1146         char *local_name = NULL;
1147
1148         cleanup_child_pid = pid;
1149         if (!read_batch) {
1150                 set_nonblocking(f_in);
1151                 set_nonblocking(f_out);
1152         }
1153
1154         io_set_sock_fds(f_in, f_out);
1155         setup_protocol(f_out,f_in);
1156
1157         /* We set our stderr file handle to blocking because ssh might have
1158          * set it to non-blocking.  This can be particularly troublesome if
1159          * stderr is a clone of stdout, because ssh would have set our stdout
1160          * to non-blocking at the same time (which can easily cause us to lose
1161          * output from our print statements).  This kluge shouldn't cause ssh
1162          * any problems for how we use it.  Note also that we delayed setting
1163          * this until after the above protocol setup so that we know for sure
1164          * that ssh is done twiddling its file descriptors.  */
1165         set_blocking(STDERR_FILENO);
1166
1167         if (am_sender) {
1168                 keep_dirlinks = 0; /* Must be disabled on the sender. */
1169
1170                 if (always_checksum
1171                  && (log_format_has(stdout_format, 'C')
1172                   || log_format_has(logfile_format, 'C')))
1173                         sender_keeps_checksum = 1;
1174
1175                 if (protocol_version >= 30)
1176                         io_start_multiplex_out(f_out);
1177                 else
1178                         io_start_buffering_out(f_out);
1179                 if (protocol_version >= 31 || (!filesfrom_host && protocol_version >= 23))
1180                         io_start_multiplex_in(f_in);
1181                 else
1182                         io_start_buffering_in(f_in);
1183                 send_filter_list(f_out);
1184                 if (filesfrom_host)
1185                         filesfrom_fd = f_in;
1186
1187                 if (write_batch && !am_server)
1188                         start_write_batch(f_out);
1189                 flist = send_file_list(f_out, argc, argv);
1190                 if (DEBUG_GTE(FLIST, 3))
1191                         rprintf(FINFO,"file list sent\n");
1192
1193                 if (protocol_version < 31 && filesfrom_host && protocol_version >= 23)
1194                         io_start_multiplex_in(f_in);
1195
1196                 io_flush(NORMAL_FLUSH);
1197                 send_files(f_in, f_out);
1198                 io_flush(FULL_FLUSH);
1199                 handle_stats(-1);
1200                 if (protocol_version >= 24)
1201                         read_final_goodbye(f_in, f_out);
1202                 if (pid != -1) {
1203                         if (DEBUG_GTE(EXIT, 2))
1204                                 rprintf(FINFO,"client_run waiting on %d\n", (int) pid);
1205                         io_flush(FULL_FLUSH);
1206                         wait_process_with_flush(pid, &exit_code);
1207                 }
1208                 output_summary();
1209                 io_flush(FULL_FLUSH);
1210                 exit_cleanup(exit_code);
1211         }
1212
1213         if (!read_batch) {
1214                 if (protocol_version >= 23)
1215                         io_start_multiplex_in(f_in);
1216                 if (need_messages_from_generator)
1217                         io_start_multiplex_out(f_out);
1218                 else
1219                         io_start_buffering_out(f_out);
1220         }
1221
1222         send_filter_list(read_batch ? -1 : f_out);
1223
1224         if (filesfrom_fd >= 0) {
1225                 start_filesfrom_forwarding(filesfrom_fd);
1226                 filesfrom_fd = -1;
1227         }
1228
1229         if (write_batch && !am_server)
1230                 start_write_batch(f_in);
1231         flist = recv_file_list(f_in, -1);
1232         if (inc_recurse && file_total == 1)
1233                 recv_additional_file_list(f_in);
1234
1235         if (flist && flist->used > 0) {
1236                 local_name = get_local_name(flist, argv[0]);
1237
1238                 check_alt_basis_dirs();
1239
1240                 exit_code2 = do_recv(f_in, f_out, local_name);
1241         } else {
1242                 handle_stats(-1);
1243                 output_summary();
1244         }
1245
1246         if (pid != -1) {
1247                 if (DEBUG_GTE(RECV, 1))
1248                         rprintf(FINFO,"client_run2 waiting on %d\n", (int) pid);
1249                 io_flush(FULL_FLUSH);
1250                 wait_process_with_flush(pid, &exit_code);
1251         }
1252
1253         return MAX(exit_code, exit_code2);
1254 }
1255
1256 static int copy_argv(char *argv[])
1257 {
1258         int i;
1259
1260         for (i = 0; argv[i]; i++) {
1261                 if (!(argv[i] = strdup(argv[i]))) {
1262                         rprintf (FERROR, "out of memory at %s(%d)\n",
1263                                  __FILE__, __LINE__);
1264                         return RERR_MALLOC;
1265                 }
1266         }
1267
1268         return 0;
1269 }
1270
1271
1272 /* Start a client for either type of remote connection.  Work out
1273  * whether the arguments request a remote shell or rsyncd connection,
1274  * and call the appropriate connection function, then run_client.
1275  *
1276  * Calls either start_socket_client (for sockets) or do_cmd and
1277  * client_run (for ssh). */
1278 static int start_client(int argc, char *argv[])
1279 {
1280         char *p, *shell_machine = NULL, *shell_user = NULL;
1281         char **remote_argv;
1282         int remote_argc;
1283         int f_in, f_out;
1284         int ret;
1285         pid_t pid;
1286
1287         /* Don't clobber argv[] so that ps(1) can still show the right
1288          * command line. */
1289         if ((ret = copy_argv(argv)) != 0)
1290                 return ret;
1291
1292         if (!read_batch) { /* for read_batch, NO source is specified */
1293                 char *path = check_for_hostspec(argv[0], &shell_machine, &rsync_port);
1294                 if (path) { /* source is remote */
1295                         char *dummy_host;
1296                         int dummy_port = 0;
1297                         *argv = path;
1298                         remote_argv = argv;
1299                         remote_argc = argc;
1300                         argv += argc - 1;
1301                         if (argc == 1 || **argv == ':')
1302                                 argc = 0; /* no dest arg */
1303                         else if (check_for_hostspec(*argv, &dummy_host, &dummy_port)) {
1304                                 rprintf(FERROR,
1305                                         "The source and destination cannot both be remote.\n");
1306                                 exit_cleanup(RERR_SYNTAX);
1307                         } else {
1308                                 remote_argc--; /* don't count dest */
1309                                 argc = 1;
1310                         }
1311                         if (filesfrom_host && *filesfrom_host
1312                             && strcmp(filesfrom_host, shell_machine) != 0) {
1313                                 rprintf(FERROR,
1314                                         "--files-from hostname is not the same as the transfer hostname\n");
1315                                 exit_cleanup(RERR_SYNTAX);
1316                         }
1317                         am_sender = 0;
1318                         if (rsync_port)
1319                                 daemon_over_rsh = shell_cmd ? 1 : -1;
1320                 } else { /* source is local, check dest arg */
1321                         am_sender = 1;
1322
1323                         if (argc > 1) {
1324                                 p = argv[--argc];
1325                                 remote_argv = argv + argc;
1326                         } else {
1327                                 static char *dotarg[1] = { "." };
1328                                 p = dotarg[0];
1329                                 remote_argv = dotarg;
1330                         }
1331                         remote_argc = 1;
1332
1333                         path = check_for_hostspec(p, &shell_machine, &rsync_port);
1334                         if (path && filesfrom_host && *filesfrom_host
1335                             && strcmp(filesfrom_host, shell_machine) != 0) {
1336                                 rprintf(FERROR,
1337                                         "--files-from hostname is not the same as the transfer hostname\n");
1338                                 exit_cleanup(RERR_SYNTAX);
1339                         }
1340                         if (!path) { /* no hostspec found, so src & dest are local */
1341                                 local_server = 1;
1342                                 if (filesfrom_host) {
1343                                         rprintf(FERROR,
1344                                                 "--files-from cannot be remote when the transfer is local\n");
1345                                         exit_cleanup(RERR_SYNTAX);
1346                                 }
1347                                 shell_machine = NULL;
1348                         } else { /* hostspec was found, so dest is remote */
1349                                 argv[argc] = path;
1350                                 if (rsync_port)
1351                                         daemon_over_rsh = shell_cmd ? 1 : -1;
1352                         }
1353                 }
1354         } else {  /* read_batch */
1355                 local_server = 1;
1356                 if (check_for_hostspec(argv[argc-1], &shell_machine, &rsync_port)) {
1357                         rprintf(FERROR, "remote destination is not allowed with --read-batch\n");
1358                         exit_cleanup(RERR_SYNTAX);
1359                 }
1360                 remote_argv = argv += argc - 1;
1361                 remote_argc = argc = 1;
1362         }
1363
1364         if (!rsync_port && remote_argc && !**remote_argv) /* Turn an empty arg into a dot dir. */
1365                 *remote_argv = ".";
1366
1367         if (am_sender) {
1368                 char *dummy_host;
1369                 int dummy_port = rsync_port;
1370                 int i;
1371                 /* For local source, extra source args must not have hostspec. */
1372                 for (i = 1; i < argc; i++) {
1373                         if (check_for_hostspec(argv[i], &dummy_host, &dummy_port)) {
1374                                 rprintf(FERROR, "Unexpected remote arg: %s\n", argv[i]);
1375                                 exit_cleanup(RERR_SYNTAX);
1376                         }
1377                 }
1378         } else {
1379                 char *dummy_host;
1380                 int dummy_port = rsync_port;
1381                 int i;
1382                 /* For remote source, any extra source args must have either
1383                  * the same hostname or an empty hostname. */
1384                 for (i = 1; i < remote_argc; i++) {
1385                         char *arg = check_for_hostspec(remote_argv[i], &dummy_host, &dummy_port);
1386                         if (!arg) {
1387                                 rprintf(FERROR, "Unexpected local arg: %s\n", remote_argv[i]);
1388                                 rprintf(FERROR, "If arg is a remote file/dir, prefix it with a colon (:).\n");
1389                                 exit_cleanup(RERR_SYNTAX);
1390                         }
1391                         if (*dummy_host && strcmp(dummy_host, shell_machine) != 0) {
1392                                 rprintf(FERROR, "All source args must come from the same machine.\n");
1393                                 exit_cleanup(RERR_SYNTAX);
1394                         }
1395                         if (rsync_port != dummy_port) {
1396                                 if (!rsync_port || !dummy_port)
1397                                         rprintf(FERROR, "All source args must use the same hostspec format.\n");
1398                                 else
1399                                         rprintf(FERROR, "All source args must use the same port number.\n");
1400                                 exit_cleanup(RERR_SYNTAX);
1401                         }
1402                         if (!rsync_port && !*arg) /* Turn an empty arg into a dot dir. */
1403                                 arg = ".";
1404                         remote_argv[i] = arg;
1405                 }
1406         }
1407
1408         if (daemon_over_rsh < 0)
1409                 return start_socket_client(shell_machine, remote_argc, remote_argv, argc, argv);
1410
1411         if (password_file && !daemon_over_rsh) {
1412                 rprintf(FERROR, "The --password-file option may only be "
1413                                 "used when accessing an rsync daemon.\n");
1414                 exit_cleanup(RERR_SYNTAX);
1415         }
1416
1417         if (connect_timeout) {
1418                 rprintf(FERROR, "The --contimeout option may only be "
1419                                 "used when connecting to an rsync daemon.\n");
1420                 exit_cleanup(RERR_SYNTAX);
1421         }
1422
1423         if (shell_machine) {
1424                 p = strrchr(shell_machine,'@');
1425                 if (p) {
1426                         *p = 0;
1427                         shell_user = shell_machine;
1428                         shell_machine = p+1;
1429                 }
1430         }
1431
1432         if (DEBUG_GTE(CMD, 2)) {
1433                 rprintf(FINFO,"cmd=%s machine=%s user=%s path=%s\n",
1434                         NS(shell_cmd), NS(shell_machine), NS(shell_user),
1435                         NS(remote_argv[0]));
1436         }
1437
1438         pid = do_cmd(shell_cmd, shell_machine, shell_user, remote_argv, remote_argc,
1439                      &f_in, &f_out);
1440
1441         /* if we're running an rsync server on the remote host over a
1442          * remote shell command, we need to do the RSYNCD protocol first */
1443         if (daemon_over_rsh) {
1444                 int tmpret;
1445                 tmpret = start_inband_exchange(f_in, f_out, shell_user, remote_argc, remote_argv);
1446                 if (tmpret < 0)
1447                         return tmpret;
1448         }
1449
1450         ret = client_run(f_in, f_out, pid, argc, argv);
1451
1452         fflush(stdout);
1453         fflush(stderr);
1454
1455         return ret;
1456 }
1457
1458
1459 static void sigusr1_handler(UNUSED(int val))
1460 {
1461         exit_cleanup(RERR_SIGNAL1);
1462 }
1463
1464 static void sigusr2_handler(UNUSED(int val))
1465 {
1466         if (!am_server)
1467                 output_summary();
1468         close_all();
1469         if (got_xfer_error)
1470                 _exit(RERR_PARTIAL);
1471         _exit(0);
1472 }
1473
1474 void remember_children(UNUSED(int val))
1475 {
1476 #ifdef WNOHANG
1477         int cnt, status;
1478         pid_t pid;
1479         /* An empty waitpid() loop was put here by Tridge and we could never
1480          * get him to explain why he put it in, so rather than taking it
1481          * out we're instead saving the child exit statuses for later use.
1482          * The waitpid() loop presumably eliminates all possibility of leaving
1483          * zombie children, maybe that's why he did it. */
1484         while ((pid = waitpid(-1, &status, WNOHANG)) > 0) {
1485                 /* save the child's exit status */
1486                 for (cnt = 0; cnt < MAXCHILDPROCS; cnt++) {
1487                         if (pid_stat_table[cnt].pid == 0) {
1488                                 pid_stat_table[cnt].pid = pid;
1489                                 pid_stat_table[cnt].status = status;
1490                                 break;
1491                         }
1492                 }
1493         }
1494 #endif
1495 #ifndef HAVE_SIGACTION
1496         signal(SIGCHLD, remember_children);
1497 #endif
1498 }
1499
1500
1501 /**
1502  * This routine catches signals and tries to send them to gdb.
1503  *
1504  * Because it's called from inside a signal handler it ought not to
1505  * use too many library routines.
1506  *
1507  * @todo Perhaps use "screen -X" instead/as well, to help people
1508  * debugging without easy access to X.  Perhaps use an environment
1509  * variable, or just call a script?
1510  *
1511  * @todo The /proc/ magic probably only works on Linux (and
1512  * Solaris?)  Can we be more portable?
1513  **/
1514 #ifdef MAINTAINER_MODE
1515 const char *get_panic_action(void)
1516 {
1517         const char *cmd_fmt = getenv("RSYNC_PANIC_ACTION");
1518
1519         if (cmd_fmt)
1520                 return cmd_fmt;
1521         return "xterm -display :0 -T Panic -n Panic -e gdb /proc/%d/exe %d";
1522 }
1523
1524
1525 /**
1526  * Handle a fatal signal by launching a debugger, controlled by $RSYNC_PANIC_ACTION.
1527  *
1528  * This signal handler is only installed if we were configured with
1529  * --enable-maintainer-mode.  Perhaps it should always be on and we
1530  * should just look at the environment variable, but I'm a bit leery
1531  * of a signal sending us into a busy loop.
1532  **/
1533 static void rsync_panic_handler(UNUSED(int whatsig))
1534 {
1535         char cmd_buf[300];
1536         int ret, pid_int = getpid();
1537
1538         snprintf(cmd_buf, sizeof cmd_buf, get_panic_action(), pid_int, pid_int);
1539
1540         /* Unless we failed to execute gdb, we allow the process to
1541          * continue.  I'm not sure if that's right. */
1542         ret = shell_exec(cmd_buf);
1543         if (ret)
1544                 _exit(ret);
1545 }
1546 #endif
1547
1548
1549 int main(int argc,char *argv[])
1550 {
1551         int ret;
1552         int orig_argc = argc;
1553         char **orig_argv = argv;
1554 #ifdef HAVE_SIGACTION
1555 # ifdef HAVE_SIGPROCMASK
1556         sigset_t sigmask;
1557
1558         sigemptyset(&sigmask);
1559 # endif
1560         sigact.sa_flags = SA_NOCLDSTOP;
1561 #endif
1562         SIGACTMASK(SIGUSR1, sigusr1_handler);
1563         SIGACTMASK(SIGUSR2, sigusr2_handler);
1564         SIGACTMASK(SIGCHLD, remember_children);
1565 #ifdef MAINTAINER_MODE
1566         SIGACTMASK(SIGSEGV, rsync_panic_handler);
1567         SIGACTMASK(SIGFPE, rsync_panic_handler);
1568         SIGACTMASK(SIGABRT, rsync_panic_handler);
1569         SIGACTMASK(SIGBUS, rsync_panic_handler);
1570 #endif
1571
1572         starttime = time(NULL);
1573         our_uid = MY_UID();
1574         our_gid = MY_GID();
1575         am_root = our_uid == 0;
1576
1577         memset(&stats, 0, sizeof(stats));
1578
1579         if (argc < 2) {
1580                 usage(FERROR);
1581                 exit_cleanup(RERR_SYNTAX);
1582         }
1583
1584         /* Get the umask for use in permission calculations.  We no longer set
1585          * it to zero; that is ugly and pointless now that all the callers that
1586          * relied on it have been reeducated to work with default ACLs. */
1587         umask(orig_umask = umask(0));
1588
1589 #if defined CONFIG_LOCALE && defined HAVE_SETLOCALE
1590         setlocale(LC_CTYPE, "");
1591 #endif
1592
1593         if (!parse_arguments(&argc, (const char ***) &argv)) {
1594                 /* FIXME: We ought to call the same error-handling
1595                  * code here, rather than relying on getopt. */
1596                 option_error();
1597                 exit_cleanup(RERR_SYNTAX);
1598         }
1599
1600         SIGACTMASK(SIGINT, sig_int);
1601         SIGACTMASK(SIGHUP, sig_int);
1602         SIGACTMASK(SIGTERM, sig_int);
1603 #if defined HAVE_SIGACTION && HAVE_SIGPROCMASK
1604         sigprocmask(SIG_UNBLOCK, &sigmask, NULL);
1605 #endif
1606
1607         /* Ignore SIGPIPE; we consistently check error codes and will
1608          * see the EPIPE. */
1609         SIGACTION(SIGPIPE, SIG_IGN);
1610 #ifdef SIGXFSZ
1611         SIGACTION(SIGXFSZ, SIG_IGN);
1612 #endif
1613
1614         /* Initialize change_dir() here because on some old systems getcwd
1615          * (implemented by forking "pwd" and reading its output) doesn't
1616          * work when there are other child processes.  Also, on all systems
1617          * that implement getcwd that way "pwd" can't be found after chroot. */
1618         change_dir(NULL, CD_NORMAL);
1619
1620         if ((write_batch || read_batch) && !am_server) {
1621                 if (write_batch)
1622                         write_batch_shell_file(orig_argc, orig_argv, argc);
1623
1624                 if (read_batch && strcmp(batch_name, "-") == 0)
1625                         batch_fd = STDIN_FILENO;
1626                 else {
1627                         batch_fd = do_open(batch_name,
1628                                    write_batch ? O_WRONLY | O_CREAT | O_TRUNC
1629                                    : O_RDONLY, S_IRUSR | S_IWUSR);
1630                 }
1631                 if (batch_fd < 0) {
1632                         rsyserr(FERROR, errno, "Batch file %s open error",
1633                                 full_fname(batch_name));
1634                         exit_cleanup(RERR_FILEIO);
1635                 }
1636                 if (read_batch)
1637                         read_stream_flags(batch_fd);
1638                 else
1639                         write_stream_flags(batch_fd);
1640         }
1641         if (write_batch < 0)
1642                 dry_run = 1;
1643
1644         if (am_server) {
1645 #ifdef ICONV_CONST
1646                 setup_iconv();
1647 #endif
1648         } else if (am_daemon)
1649                 return daemon_main();
1650
1651         if (am_server && protect_args) {
1652                 char buf[MAXPATHLEN];
1653                 protect_args = 2;
1654                 read_args(STDIN_FILENO, NULL, buf, sizeof buf, 1, &argv, &argc, NULL);
1655                 if (!parse_arguments(&argc, (const char ***) &argv)) {
1656                         option_error();
1657                         exit_cleanup(RERR_SYNTAX);
1658                 }
1659         }
1660
1661         if (argc < 1) {
1662                 usage(FERROR);
1663                 exit_cleanup(RERR_SYNTAX);
1664         }
1665
1666         if (am_server) {
1667                 set_nonblocking(STDIN_FILENO);
1668                 set_nonblocking(STDOUT_FILENO);
1669                 if (am_daemon)
1670                         return start_daemon(STDIN_FILENO, STDOUT_FILENO);
1671                 start_server(STDIN_FILENO, STDOUT_FILENO, argc, argv);
1672         }
1673
1674         ret = start_client(argc, argv);
1675         if (ret == -1)
1676                 exit_cleanup(RERR_STARTCLIENT);
1677         else
1678                 exit_cleanup(ret);
1679
1680         return ret;
1681 }