substitute exclude -> filter, as appropriate.
[rsync-patches.git] / openssl-support.diff
1 After applying this patch, run these commands for a successful build:
2
3     autoconf
4     autoheader
5     ./configure
6     make proto
7     make
8
9 Casey Marshall writes:
10
11 I've been hacking together a way to use rsync with OpenSSL, and have
12 attached my current patch against a recent CVS tree. The details of
13 this implementation are:
14
15   1. The SSL code is added as a "layer" that is forked into its own
16      process.
17
18   2. An SSL connection is established by the client issuing the
19      command:
20
21        #starttls
22
23      And, if the server allows SSL, it replies with
24
25        @RSYNCD: starttls
26
27      At which point both sides begin negotiating the SSL connection.
28      Servers that can't or don't want to use SSL just treat it as a
29      normal unknown command.
30
31   3. The SSL code is meant to be unobtrusive, and when this patch is
32      applied the program may still be built with no SSL code.
33
34   4. There are a number of details not implemented.
35
36 All warnings apply; I don't do C programming all that often, so I
37 can't say if I've left any cleanup/compatibility errors in the code.
38
39
40 --- orig/Makefile.in    2004-11-03 11:56:03
41 +++ Makefile.in 2004-10-08 20:17:06
42 @@ -39,7 +39,7 @@ OBJS3=progress.o pipe.o
43  DAEMON_OBJ = params.o loadparm.o clientserver.o access.o connection.o authenticate.o
44  popt_OBJS=popt/findme.o  popt/popt.o  popt/poptconfig.o \
45         popt/popthelp.o popt/poptparse.o
46 -OBJS=$(OBJS1) $(OBJS2) $(OBJS3) $(DAEMON_OBJ) $(LIBOBJ) $(ZLIBOBJ) @BUILD_POPT@
47 +OBJS=$(OBJS1) $(OBJS2) $(OBJS3) $(DAEMON_OBJ) $(LIBOBJ) $(ZLIBOBJ) @BUILD_POPT@ @SSL_OBJS@
48  
49  TLS_OBJ = tls.o syscall.o lib/compat.o lib/snprintf.o lib/permstring.o
50  
51 --- orig/cleanup.c      2005-01-10 09:46:11
52 +++ cleanup.c   2005-01-10 10:43:22
53 @@ -22,6 +22,9 @@
54  #include "rsync.h"
55  
56  extern int io_error;
57 +#ifdef HAVE_OPENSSL
58 +extern int use_ssl;
59 +#endif
60  extern int keep_partial;
61  extern int log_got_error;
62  extern char *partial_dir;
63 @@ -98,6 +101,11 @@ void _exit_cleanup(int code, const char 
64         signal(SIGUSR1, SIG_IGN);
65         signal(SIGUSR2, SIG_IGN);
66  
67 +#ifdef HAVE_OPENSSL
68 +       if (use_ssl)
69 +               end_tls();
70 +#endif
71 +
72         if (verbose > 3) {
73                 rprintf(FINFO,"_exit_cleanup(code=%d, file=%s, line=%d): entered\n",
74                         code, file, line);
75 --- orig/clientserver.c 2005-01-25 00:53:58
76 +++ clientserver.c      2004-10-08 20:44:59
77 @@ -47,6 +47,9 @@ extern int select_timeout;
78  extern int orig_umask;
79  extern int no_detach;
80  extern int default_af_hint;
81 +#ifdef HAVE_OPENSSL
82 +extern int use_ssl;
83 +#endif
84  extern char *bind_address;
85  extern struct filter_list_struct server_filter_list;
86  extern char *config_file;
87 @@ -100,8 +103,18 @@ int start_socket_client(char *host, char
88                 exit_cleanup(RERR_SOCKETIO);
89  
90         ret = start_inband_exchange(user, path, fd, fd, argc);
91 +       if (ret < 0)
92 +               return ret;
93 +
94 +#ifdef HAVE_OPENSSL
95 +       if (use_ssl) {
96 +               int f_in = get_tls_rfd();
97 +               int f_out = get_tls_wfd();
98 +               return client_run(f_in, f_out, -1, argc, argv);
99 +       }
100 +#endif
101  
102 -       return ret < 0? ret : client_run(fd, fd, -1, argc, argv);
103 +       return client_run(fd, fd, -1, argc, argv);
104  }
105  
106  int start_inband_exchange(char *user, char *path, int f_in, int f_out, 
107 @@ -162,6 +175,33 @@ int start_inband_exchange(char *user, ch
108         if (verbose > 1)
109                 print_child_argv(sargs);
110  
111 +#ifdef HAVE_OPENSSL
112 +       if (use_ssl) {
113 +               io_printf(f_out, "#starttls\n");
114 +               while (1) {
115 +                       if (!read_line(f_in, line, sizeof(line)-1)) {
116 +                               rprintf(FERROR, "rsync: did not receive reply to #starttls\n");
117 +                               return -1;
118 +                       }
119 +                       if (strncmp(line, "@ERROR", 6) == 0) {
120 +                               rprintf(FERROR, "%s\n", line);
121 +                               return -1;
122 +                       }
123 +                       if (strcmp(line, "@RSYNCD: starttls") == 0) {
124 +                               break;
125 +                       }
126 +                       rprintf(FINFO, "%s\n", line);
127 +               }
128 +               if (start_tls(f_in, f_out)) {
129 +                       rprintf(FERROR, "rsync: error during SSL handshake: %s\n",
130 +                               get_ssl_error());
131 +                       return -1;
132 +               }
133 +               f_in = get_tls_rfd();
134 +               f_out = get_tls_wfd();
135 +       }
136 +#endif
137 +
138         p = strchr(path,'/');
139         if (p) *p = 0;
140         io_printf(f_out, "%s\n", path);
141 @@ -190,6 +230,10 @@ int start_inband_exchange(char *user, ch
142                          * server to terminate the listing of modules.
143                          * We don't want to go on and transfer
144                          * anything; just exit. */
145 +#ifdef HAVE_OPENSSL
146 +                       if (use_ssl)
147 +                               end_tls();
148 +#endif
149                         exit(0);
150                 }
151  
152 @@ -197,6 +241,10 @@ int start_inband_exchange(char *user, ch
153                         rprintf(FERROR, "%s\n", line);
154                         /* This is always fatal; the server will now
155                          * close the socket. */
156 +#ifdef HAVE_OPENSSL
157 +                       if (use_ssl)
158 +                               end_tls();
159 +#endif
160                         return RERR_STARTCLIENT;
161                 } else {
162                         rprintf(FINFO,"%s\n", line);
163 @@ -519,6 +567,7 @@ static void send_listing(int fd)
164                 io_printf(fd,"@RSYNCD: EXIT\n");
165  }
166  
167 +
168  /* this is called when a connection is established to a client
169     and we want to start talking. The setup of the system is done from
170     here */
171 @@ -568,6 +617,9 @@ int start_daemon(int f_in, int f_out)
172         if (protocol_version > remote_protocol)
173                 protocol_version = remote_protocol;
174  
175 +#if HAVE_OPENSSL
176 +retry:
177 +#endif
178         line[0] = 0;
179         if (!read_line(f_in, line, sizeof line - 1))
180                 return -1;
181 @@ -577,6 +629,20 @@ int start_daemon(int f_in, int f_out)
182                 return -1;
183         }
184  
185 +#if HAVE_OPENSSL
186 +       if (use_ssl && strcmp(line, "#starttls") == 0) {
187 +               io_printf(f_out, "@RSYNCD: starttls\n");
188 +               if (start_tls(f_in, f_out)) {
189 +                       rprintf(FLOG, "SSL connection failed: %s\n",
190 +                               get_ssl_error());
191 +                       return -1;
192 +               }
193 +               f_in = get_tls_rfd();
194 +               f_out = get_tls_wfd();
195 +               goto retry;
196 +       }
197 +#endif
198 +
199         if (*line == '#') {
200                 /* it's some sort of command that I don't understand */
201                 io_printf(f_out, "@ERROR: Unknown command '%s'\n", line);
202 --- orig/configure.in   2005-01-10 00:21:12
203 +++ configure.in        2004-07-03 20:22:28
204 @@ -271,6 +271,21 @@ yes
205         AC_SEARCH_LIBS(getaddrinfo, inet6)
206  fi
207  
208 +AC_ARG_ENABLE(openssl,
209 +              AC_HELP_STRING([--enable-openssl], [compile SSL support with OpenSSL.]))
210 +
211 +if test "x$enable_openssl" != xno
212 +then
213 +       have_ssl=yes
214 +       AC_CHECK_LIB(ssl, SSL_library_init, , [have_ssl=no])
215 +       if test "x$have_ssl" = xyes
216 +       then
217 +               AC_DEFINE(HAVE_OPENSSL, 1, [true if you want to use SSL.])
218 +               SSL_OBJS=ssl.o
219 +               AC_SUBST(SSL_OBJS)
220 +       fi
221 +fi
222 +
223  AC_MSG_CHECKING([whether to call shutdown on all sockets])
224  case $host_os in
225         *cygwin* ) AC_MSG_RESULT(yes)
226 --- orig/main.c 2005-01-24 01:43:10
227 +++ main.c      2004-10-08 20:15:28
228 @@ -57,6 +57,9 @@ extern int write_batch;
229  extern int batch_fd;
230  extern int batch_gen_fd;
231  extern int filesfrom_fd;
232 +#ifdef HAVE_OPENSSL
233 +extern int use_ssl;
234 +#endif
235  extern pid_t cleanup_child_pid;
236  extern char *files_from;
237  extern char *remote_filesfrom_file;
238 @@ -808,33 +811,48 @@ static int start_client(int argc, char *
239         if ((rc = copy_argv(argv)))
240                 return rc;
241  
242 -       /* rsync:// always uses rsync server over direct socket connection */
243 -       if (strncasecmp(URL_PREFIX, argv[0], strlen(URL_PREFIX)) == 0
244 -           && !read_batch) {
245 -               char *host, *path;
246 +       if (!read_batch) { /* for read_batch, NO source is specified */
247 +               int url_prefix_len = sizeof URL_PREFIX - 1;
248  
249 -               host = argv[0] + strlen(URL_PREFIX);
250 -               p = strchr(host,'/');
251 -               if (p) {
252 -                       *p = '\0';
253 -                       path = p+1;
254 -               } else
255 -                       path = "";
256 -               if (*host == '[' && (p = strchr(host, ']')) != NULL) {
257 -                       host++;
258 -                       *p++ = '\0';
259 -                       if (*p != ':')
260 -                               p = NULL;
261 -               } else
262 -                       p = strchr(host, ':');
263 -               if (p) {
264 -                       rsync_port = atoi(p+1);
265 -                       *p = '\0';
266 +               /* rsync:// always uses rsync server over direct socket connection */
267 +               if (strncasecmp(URL_PREFIX, argv[0], url_prefix_len) != 0) {
268 +#ifdef HAVE_OPENSSL
269 +                       url_prefix_len = sizeof SSL_URL_PREFIX - 1;
270 +                       if (strncasecmp(SSL_URL_PREFIX, argv[0], url_prefix_len) != 0)
271 +                               url_prefix_len = 0;
272 +                       else {
273 +                               if (!use_ssl)
274 +                                       init_tls();
275 +                               use_ssl = 1;
276 +                       }
277 +#else
278 +                       url_prefix_len = 0;
279 +#endif
280 +               }
281 +               if (url_prefix_len) {
282 +                       char *host, *path;
283 +
284 +                       host = argv[0] + url_prefix_len;
285 +                       p = strchr(host,'/');
286 +                       if (p) {
287 +                               *p = '\0';
288 +                               path = p+1;
289 +                       } else
290 +                               path = "";
291 +                       if (*host == '[' && (p = strchr(host, ']')) != NULL) {
292 +                               host++;
293 +                               *p++ = '\0';
294 +                               if (*p != ':')
295 +                                       p = NULL;
296 +                       } else
297 +                               p = strchr(host, ':');
298 +                       if (p) {
299 +                               rsync_port = atoi(p+1);
300 +                               *p = '\0';
301 +                       }
302 +                       return start_socket_client(host, path, argc-1, argv+1);
303                 }
304 -               return start_socket_client(host, path, argc-1, argv+1);
305 -       }
306  
307 -       if (!read_batch) { /* for read_batch, NO source is specified */
308                 p = find_colon(argv[0]);
309                 if (p) { /* source is remote */
310                         if (remote_filesfrom_file
311 @@ -866,12 +884,26 @@ static int start_client(int argc, char *
312                         argv++;
313                 } else { /* source is local */
314                         am_sender = 1;
315 -
316 +                       url_prefix_len = sizeof URL_PREFIX - 1;
317                         /* rsync:// destination uses rsync server over direct socket */
318 -                       if (strncasecmp(URL_PREFIX, argv[argc-1], strlen(URL_PREFIX)) == 0) {
319 +                       if (strncasecmp(URL_PREFIX, argv[argc-1], url_prefix_len) != 0) {
320 +#ifdef HAVE_OPENSSL
321 +                               url_prefix_len = sizeof SSL_URL_PREFIX - 1;
322 +                               if (strncasecmp(SSL_URL_PREFIX, argv[argc-1], url_prefix_len) != 0)
323 +                                       url_prefix_len = 0;
324 +                               else {
325 +                                       if (!use_ssl)
326 +                                               init_tls();
327 +                                       use_ssl = 1;
328 +                               }
329 +#else
330 +                               url_prefix_len = 0;
331 +#endif
332 +                       }
333 +                       if (url_prefix_len) {
334                                 char *host, *path;
335  
336 -                               host = argv[argc-1] + strlen(URL_PREFIX);
337 +                               host = argv[argc-1] + url_prefix_len;
338                                 p = strchr(host,'/');
339                                 if (p) {
340                                         *p = '\0';
341 --- orig/options.c      2005-01-25 03:26:51
342 +++ options.c   2004-11-27 18:31:46
343 @@ -144,6 +144,14 @@ int quiet = 0;
344  int always_checksum = 0;
345  int list_only = 0;
346  
347 +#ifdef HAVE_OPENSSL
348 +int use_ssl = 0;
349 +char *ssl_cert_path = NULL;
350 +char *ssl_key_path = NULL;
351 +char *ssl_key_passwd = NULL;
352 +char *ssl_ca_path = NULL;
353 +#endif
354 +
355  #define MAX_BATCH_NAME_LEN 256 /* Must be less than MAXPATHLEN-13 */
356  char *batch_name = NULL;
357  
358 @@ -166,6 +174,7 @@ static void print_rsync_version(enum log
359         char const *hardlinks = "no ";
360         char const *links = "no ";
361         char const *ipv6 = "no ";
362 +       char const *ssl = "no ";
363         STRUCT_STAT *dumstat;
364  
365  #ifdef HAVE_SOCKETPAIR
366 @@ -188,6 +197,10 @@ static void print_rsync_version(enum log
367         ipv6 = "";
368  #endif
369  
370 +#ifdef HAVE_OPENSSL
371 +       ssl = "";
372 +#endif
373 +
374         rprintf(f, "%s  version %s  protocol version %d\n",
375                 RSYNC_NAME, RSYNC_VERSION, PROTOCOL_VERSION);
376         rprintf(f,
377 @@ -201,10 +214,10 @@ static void print_rsync_version(enum log
378         /* Note that this field may not have type ino_t.  It depends
379          * on the complicated interaction between largefile feature
380          * macros. */
381 -       rprintf(f, "              %sinplace, %sIPv6, %d-bit system inums, %d-bit internal inums\n",
382 +       rprintf(f, "              %sinplace, %sIPv6, %d-bit system inums, %d-bit internal inums, %sssl\n",
383                 have_inplace, ipv6,
384                 (int) (sizeof dumstat->st_ino * 8),
385 -               (int) (sizeof (int64) * 8));
386 +               (int) (sizeof (int64) * 8), ssl);
387  #ifdef MAINTAINER_MODE
388         rprintf(f, "              panic action: \"%s\"\n",
389                 get_panic_action());
390 @@ -325,6 +338,13 @@ void usage(enum logcode F)
391    rprintf(F," -4, --ipv4                  prefer IPv4\n");
392    rprintf(F," -6, --ipv6                  prefer IPv6\n");
393  #endif
394 +#ifdef HAVE_OPENSSL
395 +  rprintf(F,"     --ssl                   allow socket connections to use SSL\n");
396 +  rprintf(F,"     --ssl-cert=FILE         path to server's SSL certificate\n");
397 +  rprintf(F,"     --ssl-key=FILE          path to server's SSL private key\n");
398 +  rprintf(F,"     --ssl-key-passwd=PASS   password for PEM-encoded private key\n");
399 +  rprintf(F,"     --ssl-ca-certs=FILE     path to trusted CA certificates\n");
400 +#endif
401    rprintf(F," -h, --help                  show this help screen\n");
402  
403    rprintf(F,"\nUse \"rsync --daemon --help\" to see the daemon-mode command-line options.\n");
404 @@ -335,7 +355,7 @@ void usage(enum logcode F)
405  enum {OPT_VERSION = 1000, OPT_DAEMON, OPT_SENDER, OPT_EXCLUDE, OPT_EXCLUDE_FROM,
406        OPT_FILTER, OPT_COMPARE_DEST, OPT_COPY_DEST, OPT_LINK_DEST,
407        OPT_INCLUDE, OPT_INCLUDE_FROM, OPT_MODIFY_WINDOW,
408 -      OPT_READ_BATCH, OPT_WRITE_BATCH, OPT_TIMEOUT, OPT_MAX_SIZE,
409 +      OPT_READ_BATCH, OPT_WRITE_BATCH, OPT_TIMEOUT, OPT_MAX_SIZE, OPT_USE_SSL,
410        OPT_REFUSED_BASE = 9000};
411  
412  static struct poptOption long_options[] = {
413 @@ -428,6 +448,13 @@ static struct poptOption long_options[] 
414    {"ipv4",            '4', POPT_ARG_VAL,    &default_af_hint, AF_INET, 0, 0 },
415    {"ipv6",            '6', POPT_ARG_VAL,    &default_af_hint, AF_INET6, 0, 0 },
416  #endif
417 +#ifdef HAVE_OPENSSL
418 +  {"ssl",              0,  POPT_ARG_NONE,   0, OPT_USE_SSL, 0, 0},
419 +  {"ssl-cert",         0,  POPT_ARG_STRING, &ssl_cert_path, OPT_USE_SSL, 0, 0},
420 +  {"ssl-key",          0,  POPT_ARG_STRING, &ssl_key_path, OPT_USE_SSL, 0, 0},
421 +  {"ssl-key-passwd",   0,  POPT_ARG_STRING, &ssl_key_passwd, OPT_USE_SSL, 0, 0},
422 +  {"ssl-ca-certs",     0,  POPT_ARG_STRING, &ssl_ca_path, OPT_USE_SSL, 0, 0},
423 +#endif
424    /* All these options switch us into daemon-mode option-parsing. */
425    {"address",          0,  POPT_ARG_STRING, 0, OPT_DAEMON, 0, 0 },
426    {"config",           0,  POPT_ARG_STRING, 0, OPT_DAEMON, 0, 0 },
427 @@ -788,6 +815,12 @@ int parse_arguments(int *argc, const cha
428                         basis_dir[basis_dir_cnt++] = (char *)arg;
429                         break;
430  
431 +               case OPT_USE_SSL:
432 +#ifdef HAVE_OPENSSL
433 +                       use_ssl = 1;
434 +#endif
435 +                       break;
436 +
437                 default:
438                         /* A large opt value means that set_refuse_options()
439                          * turned this option off (opt-BASE is its index). */
440 @@ -995,6 +1028,17 @@ int parse_arguments(int *argc, const cha
441                         bwlimit_writemax = 512;
442         }
443  
444 +#ifdef HAVE_OPENSSL
445 +       if (use_ssl) {
446 +               if (init_tls()) {
447 +                       snprintf(err_buf, sizeof(err_buf),
448 +                                "Openssl error: %s\n",
449 +                                get_ssl_error());
450 +                       return 0;
451 +               }
452 +       }
453 +#endif
454 +
455         if (inplace) {
456  #if HAVE_FTRUNCATE
457                 if (partial_dir) {
458 --- orig/rsync.h        2005-01-25 00:53:58
459 +++ rsync.h     2004-10-08 21:01:33
460 @@ -32,6 +32,7 @@
461  
462  #define DEFAULT_LOCK_FILE "/var/run/rsyncd.lock"
463  #define URL_PREFIX "rsync://"
464 +#define SSL_URL_PREFIX "rsyncs://"
465  
466  #define BACKUP_SUFFIX "~"
467  
468 @@ -339,6 +340,11 @@ enum msgcode {
469  #define INT64_IS_OFF_T
470  #endif
471  
472 +#if HAVE_OPENSSL
473 +#include <openssl/ssl.h>
474 +#include <openssl/err.h>
475 +#endif
476 +
477  /* Starting from protocol version 26, we always use 64-bit
478   * ino_t and dev_t internally, even if this platform does not
479   * allow files to have 64-bit inums.  That's because the
480 --- orig/ssl.c  2004-10-08 19:37:22
481 +++ ssl.c       2004-10-08 19:37:22
482 @@ -0,0 +1,366 @@
483 +/* -*- c-file-style: "linux" -*-
484 + * ssl.c: operations for negotiating SSL rsync connections. 
485 + *
486 + * Copyright (C) 2003  Casey Marshall <rsdio@metastatic.org>
487 + *
488 + * This program is free software; you can redistribute it and/or modify
489 + * it under the terms of the GNU General Public License as published by
490 + * the Free Software Foundation; either version 2 of the License, or
491 + * (at your option) any later version.
492 + * 
493 + * This program is distributed in the hope that it will be useful,
494 + * but WITHOUT ANY WARRANTY; without even the implied warranty of
495 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
496 + * GNU General Public License for more details.
497 + * 
498 + * You should have received a copy of the GNU General Public License
499 + * along with this program; if not, write to the Free Software
500 + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
501 + */
502 +
503 +#include "rsync.h"
504 +
505 +#ifdef HAVE_SYS_SELECT_H
506 +#include <sys/select.h>
507 +#else
508 +#include <sys/time.h>
509 +#include <sys/types.h>
510 +#include <unistd.h>
511 +#endif
512 +#include <string.h>
513 +
514 +#define BUF_SIZE 1024
515 +
516 +extern int verbose;
517 +extern int am_daemon;
518 +extern int am_server;
519 +
520 +extern char *ssl_cert_path;
521 +extern char *ssl_key_path;
522 +extern char *ssl_key_passwd;
523 +extern char *ssl_ca_path;
524 +
525 +static SSL_CTX *ssl_ctx;
526 +static SSL *ssl;
527 +static int tls_read[2] = { -1, -1 };
528 +static int tls_write[2] = { -1, -1 };
529 +static int ssl_running;
530 +static int ssl_pid = -1;
531 +
532 +/**
533 + * A non-interactive callback to be passed to SSL_CTX_set_default_password_cb,
534 + * which merely copies the value of ssl_key_passwd into buf. This is
535 + * used for when the private key password is supplied via an option.
536 + */
537 +static int default_password_cb(char *buf, int n, UNUSED(int f), UNUSED(void *u))
538 +{
539 +       if (ssl_key_passwd == NULL || n < (int)strlen(ssl_key_passwd))
540 +               return 0;
541 +       strncpy(buf, ssl_key_passwd, n-1);
542 +       return strlen(ssl_key_passwd);
543 +}
544 +
545 +/**
546 + * If verbose, this method traces the status of the SSL handshake.
547 + */
548 +static void info_callback(const SSL *ssl, int cb, int val)
549 +{
550 +       char buf[128];
551 +       char *cbs;
552 +
553 +       switch (cb) {
554 +       case SSL_CB_LOOP:
555 +               cbs = "SSL_CB_LOOP";
556 +               break;
557 +       case SSL_CB_EXIT:
558 +               cbs = "SSL_CB_EXIT";
559 +               break;
560 +       case SSL_CB_READ:
561 +               cbs = "SSL_CB_READ";
562 +               break;
563 +       case SSL_CB_WRITE:
564 +               cbs = "SSL_CB_WRITE";
565 +               break;
566 +       case SSL_CB_ALERT:
567 +               cbs = "SSL_CB_ALERT";
568 +               break;
569 +       case SSL_CB_READ_ALERT:
570 +               cbs = "SSL_CB_READ_ALERT";
571 +               break;
572 +       case SSL_CB_WRITE_ALERT:
573 +               cbs = "SSL_CB_WRITE_ALERT";
574 +               break;
575 +       case SSL_CB_ACCEPT_LOOP:
576 +               cbs = "SSL_CB_ACCEPT_LOOP";
577 +               break;
578 +       case SSL_CB_ACCEPT_EXIT:
579 +               cbs = "SSL_CB_ACCEPT_EXIT";
580 +               break;
581 +       case SSL_CB_CONNECT_LOOP:
582 +               cbs = "SSL_CB_CONNECT_LOOP";
583 +               break;
584 +       case SSL_CB_CONNECT_EXIT:
585 +               cbs = "SSL_CB_CONNECT_EXIT";
586 +               break;
587 +       case SSL_CB_HANDSHAKE_START:
588 +               cbs = "SSL_CB_HANDSHAKE_START";
589 +               break;
590 +       case SSL_CB_HANDSHAKE_DONE:
591 +               cbs = "SSL_CB_HANDSHAKE_DONE";
592 +               break;
593 +       default:
594 +               snprintf(buf, sizeof buf, "??? (%d)", cb);
595 +               cbs = buf;
596 +               break;
597 +       }
598 +       if (verbose > 2) {
599 +               rprintf(FLOG, "SSL: info_callback(%p,%s,%d)\n", ssl, cbs, val);
600 +               if (cb == SSL_CB_HANDSHAKE_DONE) {
601 +                       SSL_CIPHER_description(SSL_get_current_cipher((SSL*)ssl),
602 +                                              buf, sizeof buf);
603 +                       rprintf(FLOG, "SSL: cipher: %s", buf);
604 +               }
605 +       }
606 +}
607 +
608 +/**
609 + * Initializes the SSL context for TLSv1 connections; returns zero on
610 + * success.
611 + */
612 +int init_tls(void)
613 +{
614 +       if (ssl_ctx)
615 +               return 0;
616 +       SSL_library_init();
617 +       SSL_load_error_strings();
618 +       ssl_ctx = SSL_CTX_new(TLSv1_method());
619 +       if (!ssl_ctx)
620 +               return 1;
621 +       SSL_CTX_set_info_callback(ssl_ctx, info_callback);
622 +
623 +       /* Sets the certificate sent to the other party. */
624 +       if (ssl_cert_path != NULL
625 +           && SSL_CTX_use_certificate_file(ssl_ctx, ssl_cert_path,
626 +                                           SSL_FILETYPE_PEM) != 1)
627 +               return 1;
628 +       /* Set up the simple non-interactive callback if the password
629 +        * was supplied on the command line. */
630 +       if (ssl_key_passwd != NULL)
631 +               SSL_CTX_set_default_passwd_cb(ssl_ctx, default_password_cb);
632 +       /* Sets the private key that matches the public certificate. */
633 +       if (ssl_key_path != NULL) {
634 +               if (SSL_CTX_use_PrivateKey_file(ssl_ctx, ssl_key_path,
635 +                                               SSL_FILETYPE_PEM) != 1)
636 +                       return 1;
637 +               if (SSL_CTX_check_private_key(ssl_ctx) != 1)
638 +                       return 1;
639 +       }
640 +       if (ssl_ca_path != NULL
641 +           && !SSL_CTX_load_verify_locations(ssl_ctx, ssl_ca_path, NULL))
642 +               return 1;
643 +
644 +       return 0;
645 +}
646 +
647 +/**
648 + * Returns the error string for the current SSL error, if any.
649 + */
650 +char *get_ssl_error(void)
651 +{
652 +       return ERR_error_string(ERR_get_error(), NULL);
653 +}
654 +
655 +/**
656 + * Returns the input file descriptor for the SSL connection.
657 + */
658 +int get_tls_rfd(void)
659 +{
660 +       return tls_read[0];
661 +}
662 +
663 +/**
664 + * Returns the output file descriptor for the SSL connection.
665 + */
666 +int get_tls_wfd(void)
667 +{
668 +       return tls_write[1];
669 +}
670 +
671 +/**
672 + * Signal handler that ends the SSL connection.
673 + */
674 +static RETSIGTYPE tls_sigusr1(int UNUSED(val))
675 +{
676 +       if (ssl) {
677 +               SSL_shutdown(ssl);
678 +               SSL_free(ssl);
679 +               ssl = NULL;
680 +       }
681 +       ssl_running = 0;
682 +}
683 +
684 +/**
685 + * Negotiates the TLS connection, creates a socket pair for communicating
686 + * with the rsync process, then forks into a new process that will handle
687 + * the communication.
688 + *
689 + * 0 is returned on success.
690 + */
691 +int start_tls(int f_in, int f_out)
692 +{
693 +       int tls_fd;
694 +       int n = 0, r;
695 +       unsigned char buf1[BUF_SIZE], buf2[BUF_SIZE];
696 +       int avail1 = 0, avail2 = 0, write1 = 0, write2 = 0;
697 +       fd_set rd, wd;
698 +
699 +       if (fd_pair(tls_read))
700 +               return 1;
701 +       if (fd_pair(tls_write))
702 +               return 1;
703 +
704 +       set_blocking(tls_read[0]);
705 +       set_blocking(tls_read[1]);
706 +       set_blocking(tls_write[0]);
707 +       set_blocking(tls_write[1]);
708 +       set_blocking(f_in);
709 +       set_blocking(f_out);
710 +
711 +       ssl_pid = do_fork();
712 +       if (ssl_pid < 0)
713 +               return -1;
714 +       if (ssl_pid != 0) {
715 +               close(tls_write[0]);
716 +               close(tls_read[1]);
717 +               return 0;
718 +       }
719 +
720 +       signal(SIGUSR1, tls_sigusr1);
721 +       ssl = SSL_new(ssl_ctx);
722 +       if (!ssl)
723 +               goto closed;
724 +       if (am_daemon || am_server)
725 +               SSL_set_accept_state(ssl);
726 +       else
727 +               SSL_set_connect_state(ssl);
728 +       SSL_set_rfd(ssl, f_in);
729 +       SSL_set_wfd(ssl, f_out);
730 +
731 +       tls_fd = SSL_get_fd(ssl);
732 +       n = tls_write[0];
733 +       n = MAX(tls_read[1], n);
734 +       n = MAX(tls_fd, n) + 1;
735 +
736 +       ssl_running = 1;
737 +       while (ssl_running) {
738 +               FD_ZERO(&rd);
739 +               FD_ZERO(&wd);
740 +               FD_SET(tls_write[0], &rd);
741 +               FD_SET(tls_read[1], &wd);
742 +               FD_SET(tls_fd, &rd);
743 +               FD_SET(tls_fd, &wd);
744 +
745 +               r = select(n, &rd, &wd, NULL, NULL);
746 +
747 +               if (r == -1 && errno == EINTR)
748 +                       continue;
749 +               if (FD_ISSET(tls_write[0], &rd)) {
750 +                       r = read(tls_write[0], buf1+avail1, BUF_SIZE-avail1);
751 +                       if (r >= 0)
752 +                               avail1 += r;
753 +                       else {
754 +                               rprintf(FERROR, "pipe read error: %s\n",
755 +                                       strerror(errno));
756 +                               break;
757 +                       }
758 +               }
759 +               if (FD_ISSET(tls_fd, &rd)) {
760 +                       r = SSL_read(ssl, buf2+avail2, BUF_SIZE-avail2);
761 +                       if (r > 0)
762 +                               avail2 += r;
763 +                       else {
764 +                               switch (SSL_get_error(ssl, r)) {
765 +                               case SSL_ERROR_ZERO_RETURN:
766 +                                       goto closed;
767 +                               case SSL_ERROR_WANT_READ:
768 +                               case SSL_ERROR_WANT_WRITE:
769 +                                       break;
770 +                               case SSL_ERROR_SYSCALL:
771 +                                       if (r == 0)
772 +                                               rprintf(FERROR, "SSL spurious EOF\n");
773 +                                       else
774 +                                               rprintf(FERROR, "SSL I/O error: %s\n",
775 +                                                       strerror(errno));
776 +                                       goto closed;
777 +                               case SSL_ERROR_SSL:
778 +                                       rprintf(FERROR, "SSL: %s\n",
779 +                                               ERR_error_string(ERR_get_error(), NULL));
780 +                                       goto closed;
781 +                               default:
782 +                                       rprintf(FERROR, "unexpected ssl error %d\n", r);
783 +                                       goto closed;
784 +                               }
785 +                       }
786 +               }
787 +               if (FD_ISSET(tls_read[1], &wd) && write2 < avail2) {
788 +                       r = write(tls_read[1], buf2+write2, avail2-write2);
789 +                       if (r >= 0)
790 +                               write2 += r;
791 +                       else {
792 +                               rprintf(FERROR, "pipe write error: %s\n",
793 +                                       strerror(errno));
794 +                               break;
795 +                       }
796 +               }
797 +               if (FD_ISSET(tls_fd, &wd) && write1 < avail1) {
798 +                       r = SSL_write(ssl, buf1+write1, avail1-write1);
799 +                       if (r > 0)
800 +                               write1 += r;
801 +                       else {
802 +                               switch (SSL_get_error(ssl, r)) {
803 +                               case SSL_ERROR_ZERO_RETURN:
804 +                                       goto closed;
805 +                               case SSL_ERROR_WANT_READ:
806 +                               case SSL_ERROR_WANT_WRITE:
807 +                                       break;
808 +                               case SSL_ERROR_SYSCALL:
809 +                                       if (r == 0)
810 +                                               rprintf(FERROR, "SSL: spurious EOF\n");
811 +                                       else
812 +                                               rprintf(FERROR, "SSL: I/O error: %s\n",
813 +                                                       strerror(errno));
814 +                                       goto closed;
815 +                               case SSL_ERROR_SSL:
816 +                                       rprintf(FERROR, "SSL: %s\n",
817 +                                               ERR_error_string(ERR_get_error(), NULL));
818 +                                       goto closed;
819 +                               default:
820 +                                       rprintf(FERROR, "unexpected ssl error %d\n", r);
821 +                                       goto closed;
822 +                               }
823 +                       }
824 +               }
825 +               if (avail1 == write1)
826 +                       avail1 = write1 = 0;
827 +               if (avail2 == write2)
828 +                       avail2 = write2 = 0;
829 +       }
830 +
831 +       /* XXX I'm pretty sure that there is a lot that I am not considering
832 +          here. Bugs? Yes, probably. */
833 +
834 +       /* We're finished. */
835 +    closed:
836 +       close(tls_read[1]);
837 +       close(tls_write[0]);
838 +       exit(0);
839 +}
840 +
841 +/**
842 + * Ends the TLS connection.
843 + */
844 +void end_tls(void)
845 +{
846 +       if (ssl_pid > 0)
847 +               kill(ssl_pid, SIGUSR1);
848 +}