compat.c

   1 /*
   2  * Compatibility routines for older rsync protocol versions.
   3  *
   4  * Copyright (C) Andrew Tridgell 1996
   5  * Copyright (C) Paul Mackerras 1996
   6  * Copyright (C) 2004-2020 Wayne Davison
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 3 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License along
  19  * with this program; if not, visit the http://fsf.org website.
  20  */
  21
  22 #include "rsync.h"
  23
  24 int remote_protocol = 0;
  25 int file_extra_cnt = 0; /* count of file-list extras that everyone gets */
  26 int inc_recurse = 0;
  27 int compat_flags = 0;
  28 int use_safe_inc_flist = 0;
  29 int want_xattr_optim = 0;
  30 int proper_seed_order = 0;
  31 int inplace_partial = 0;
  32
  33 extern int am_server;
  34 extern int am_sender;
  35 extern int local_server;
  36 extern int inplace;
  37 extern int recurse;
  38 extern int use_qsort;
  39 extern int allow_inc_recurse;
  40 extern int preallocate_files;
  41 extern int append_mode;
  42 extern int fuzzy_basis;
  43 extern int read_batch;
  44 extern int delay_updates;
  45 extern int checksum_seed;
  46 extern int basis_dir_cnt;
  47 extern int prune_empty_dirs;
  48 extern int protocol_version;
  49 extern int protect_args;
  50 extern int preserve_uid;
  51 extern int preserve_gid;
  52 extern int preserve_atimes;
  53 extern int preserve_acls;
  54 extern int preserve_xattrs;
  55 extern int need_messages_from_generator;
  56 extern int delete_mode, delete_before, delete_during, delete_after;
  57 extern char *shell_cmd;
  58 extern char *partial_dir;
  59 extern char *dest_option;
  60 extern char *files_from;
  61 extern char *filesfrom_host;
  62 extern filter_rule_list filter_list;
  63 extern int need_unsorted_flist;
  64 #ifdef ICONV_OPTION
  65 extern iconv_t ic_send, ic_recv;
  66 extern char *iconv_opt;
  67 #endif
  68
  69 /* These index values are for the file-list's extra-attribute array. */
  70 int pathname_ndx, depth_ndx, atimes_ndx, uid_ndx, gid_ndx, acls_ndx, xattrs_ndx, unsort_ndx;
  71
  72 int receiver_symlink_times = 0; /* receiver can set the time on a symlink */
  73 int sender_symlink_iconv = 0;   /* sender should convert symlink content */
  74
  75 #ifdef ICONV_OPTION
  76 int filesfrom_convert = 0;
  77 #endif
  78
  79 #define CF_INC_RECURSE   (1<<0)
  80 #define CF_SYMLINK_TIMES (1<<1)
  81 #define CF_SYMLINK_ICONV (1<<2)
  82 #define CF_SAFE_FLIST    (1<<3)
  83 #define CF_AVOID_XATTR_OPTIM (1<<4)
  84 #define CF_CHKSUM_SEED_FIX (1<<5)
  85 #define CF_INPLACE_PARTIAL_DIR (1<<6)
  86
  87 static const char *client_info;
  88
  89 /* The server makes sure that if either side only supports a pre-release
  90  * version of a protocol, that both sides must speak a compatible version
  91  * of that protocol for it to be advertised as available. */
  92 static void check_sub_protocol(void)
  93 {
  94         char *dot;
  95         int their_protocol, their_sub;
  96 #if SUBPROTOCOL_VERSION != 0
  97         int our_sub = protocol_version < PROTOCOL_VERSION ? 0 : SUBPROTOCOL_VERSION;
  98 #else
  99         int our_sub = 0;
 100 #endif
 101
 102         /* client_info starts with VER.SUB string if client is a pre-release. */
 103         if (!(their_protocol = atoi(client_info))
 104          || !(dot = strchr(client_info, '.'))
 105          || !(their_sub = atoi(dot+1))) {
 106 #if SUBPROTOCOL_VERSION != 0
 107                 if (our_sub)
 108                         protocol_version--;
 109 #endif
 110                 return;
 111         }
 112
 113         if (their_protocol < protocol_version) {
 114                 if (their_sub)
 115                         protocol_version = their_protocol - 1;
 116                 return;
 117         }
 118
 119         if (their_protocol > protocol_version)
 120                 their_sub = 0; /* 0 == final version of older protocol */
 121         if (their_sub != our_sub)
 122                 protocol_version--;
 123 }
 124
 125 void set_allow_inc_recurse(void)
 126 {
 127         client_info = shell_cmd ? shell_cmd : "";
 128
 129         if (!recurse || use_qsort)
 130                 allow_inc_recurse = 0;
 131         else if (!am_sender
 132          && (delete_before || delete_after
 133           || delay_updates || prune_empty_dirs))
 134                 allow_inc_recurse = 0;
 135         else if (am_server && !local_server
 136          && (strchr(client_info, 'i') == NULL))
 137                 allow_inc_recurse = 0;
 138 }
 139
 140 void setup_protocol(int f_out,int f_in)
 141 {
 142         assert(file_extra_cnt == 0);
 143         assert(EXTRA64_CNT == 2 || EXTRA64_CNT == 1);
 144
 145         /* All int64 values must be set first so that they are guaranteed to be
 146          * aligned for direct int64-pointer memory access. */
 147         if (preserve_atimes)
 148                 atimes_ndx = (file_extra_cnt += EXTRA64_CNT);
 149         if (am_sender) /* This is most likely in the in64 union as well. */
 150                 pathname_ndx = (file_extra_cnt += PTR_EXTRA_CNT);
 151         else
 152                 depth_ndx = ++file_extra_cnt;
 153         if (preserve_uid)
 154                 uid_ndx = ++file_extra_cnt;
 155         if (preserve_gid)
 156                 gid_ndx = ++file_extra_cnt;
 157         if (preserve_acls && !am_sender)
 158                 acls_ndx = ++file_extra_cnt;
 159         if (preserve_xattrs)
 160                 xattrs_ndx = ++file_extra_cnt;
 161
 162         if (am_server)
 163                 set_allow_inc_recurse();
 164
 165         if (remote_protocol == 0) {
 166                 if (am_server && !local_server)
 167                         check_sub_protocol();
 168                 if (!read_batch)
 169                         write_int(f_out, protocol_version);
 170                 remote_protocol = read_int(f_in);
 171                 if (protocol_version > remote_protocol)
 172                         protocol_version = remote_protocol;
 173         }
 174         if (read_batch && remote_protocol > protocol_version) {
 175                 rprintf(FERROR, "The protocol version in the batch file is too new (%d > %d).\n",
 176                         remote_protocol, protocol_version);
 177                 exit_cleanup(RERR_PROTOCOL);
 178         }
 179
 180         if (DEBUG_GTE(PROTO, 1)) {
 181                 rprintf(FINFO, "(%s) Protocol versions: remote=%d, negotiated=%d\n",
 182                         am_server? "Server" : "Client", remote_protocol, protocol_version);
 183         }
 184         if (remote_protocol < MIN_PROTOCOL_VERSION
 185          || remote_protocol > MAX_PROTOCOL_VERSION) {
 186                 rprintf(FERROR,"protocol version mismatch -- is your shell clean?\n");
 187                 rprintf(FERROR,"(see the rsync man page for an explanation)\n");
 188                 exit_cleanup(RERR_PROTOCOL);
 189         }
 190         if (remote_protocol < OLD_PROTOCOL_VERSION) {
 191                 rprintf(FINFO,"%s is very old version of rsync, upgrade recommended.\n",
 192                         am_server? "Client" : "Server");
 193         }
 194         if (protocol_version < MIN_PROTOCOL_VERSION) {
 195                 rprintf(FERROR, "--protocol must be at least %d on the %s.\n",
 196                         MIN_PROTOCOL_VERSION, am_server? "Server" : "Client");
 197                 exit_cleanup(RERR_PROTOCOL);
 198         }
 199         if (protocol_version > PROTOCOL_VERSION) {
 200                 rprintf(FERROR, "--protocol must be no more than %d on the %s.\n",
 201                         PROTOCOL_VERSION, am_server? "Server" : "Client");
 202                 exit_cleanup(RERR_PROTOCOL);
 203         }
 204         if (read_batch)
 205                 check_batch_flags();
 206
 207 #ifndef SUPPORT_PREALLOCATION
 208         if (preallocate_files && !am_sender) {
 209                 rprintf(FERROR, "preallocation is not supported on this %s\n",
 210                         am_server ? "Server" : "Client");
 211                 exit_cleanup(RERR_SYNTAX);
 212         }
 213 #endif
 214
 215         if (protocol_version < 30) {
 216                 if (append_mode == 1)
 217                         append_mode = 2;
 218                 if (preserve_acls && !local_server) {
 219                         rprintf(FERROR,
 220                             "--acls requires protocol 30 or higher"
 221                             " (negotiated %d).\n",
 222                             protocol_version);
 223                         exit_cleanup(RERR_PROTOCOL);
 224                 }
 225                 if (preserve_xattrs && !local_server) {
 226                         rprintf(FERROR,
 227                             "--xattrs requires protocol 30 or higher"
 228                             " (negotiated %d).\n",
 229                             protocol_version);
 230                         exit_cleanup(RERR_PROTOCOL);
 231                 }
 232         }
 233
 234         if (delete_mode && !(delete_before+delete_during+delete_after)) {
 235                 if (protocol_version < 30)
 236                         delete_before = 1;
 237                 else
 238                         delete_during = 1;
 239         }
 240
 241         if (protocol_version < 29) {
 242                 if (fuzzy_basis) {
 243                         rprintf(FERROR,
 244                             "--fuzzy requires protocol 29 or higher"
 245                             " (negotiated %d).\n",
 246                             protocol_version);
 247                         exit_cleanup(RERR_PROTOCOL);
 248                 }
 249
 250                 if (basis_dir_cnt && inplace) {
 251                         rprintf(FERROR,
 252                             "%s with --inplace requires protocol 29 or higher"
 253                             " (negotiated %d).\n",
 254                             dest_option, protocol_version);
 255                         exit_cleanup(RERR_PROTOCOL);
 256                 }
 257
 258                 if (basis_dir_cnt > 1) {
 259                         rprintf(FERROR,
 260                             "Using more than one %s option requires protocol"
 261                             " 29 or higher (negotiated %d).\n",
 262                             dest_option, protocol_version);
 263                         exit_cleanup(RERR_PROTOCOL);
 264                 }
 265
 266                 if (prune_empty_dirs) {
 267                         rprintf(FERROR,
 268                             "--prune-empty-dirs requires protocol 29 or higher"
 269                             " (negotiated %d).\n",
 270                             protocol_version);
 271                         exit_cleanup(RERR_PROTOCOL);
 272                 }
 273         } else if (protocol_version >= 30) {
 274                 if (am_server) {
 275                         compat_flags = allow_inc_recurse ? CF_INC_RECURSE : 0;
 276 #ifdef CAN_SET_SYMLINK_TIMES
 277                         compat_flags |= CF_SYMLINK_TIMES;
 278 #endif
 279 #ifdef ICONV_OPTION
 280                         compat_flags |= CF_SYMLINK_ICONV;
 281 #endif
 282                         if (local_server || strchr(client_info, 'f') != NULL)
 283                                 compat_flags |= CF_SAFE_FLIST;
 284                         if (local_server || strchr(client_info, 'x') != NULL)
 285                                 compat_flags |= CF_AVOID_XATTR_OPTIM;
 286                         if (local_server || strchr(client_info, 'C') != NULL)
 287                                 compat_flags |= CF_CHKSUM_SEED_FIX;
 288                         if (local_server || strchr(client_info, 'I') != NULL)
 289                                 compat_flags |= CF_INPLACE_PARTIAL_DIR;
 290                         write_byte(f_out, compat_flags);
 291                 } else
 292                         compat_flags = read_byte(f_in);
 293                 /* The inc_recurse var MUST be set to 0 or 1. */
 294                 inc_recurse = compat_flags & CF_INC_RECURSE ? 1 : 0;
 295                 want_xattr_optim = protocol_version >= 31 && !(compat_flags & CF_AVOID_XATTR_OPTIM);
 296                 proper_seed_order = compat_flags & CF_CHKSUM_SEED_FIX ? 1 : 0;
 297                 if (am_sender) {
 298                         receiver_symlink_times = am_server
 299                             ? strchr(client_info, 'L') != NULL
 300                             : !!(compat_flags & CF_SYMLINK_TIMES);
 301                 }
 302 #ifdef CAN_SET_SYMLINK_TIMES
 303                 else
 304                         receiver_symlink_times = 1;
 305 #endif
 306 #ifdef ICONV_OPTION
 307                 sender_symlink_iconv = iconv_opt && (am_server
 308                     ? local_server || strchr(client_info, 's') != NULL
 309                     : !!(compat_flags & CF_SYMLINK_ICONV));
 310 #endif
 311                 if (inc_recurse && !allow_inc_recurse) {
 312                         /* This should only be able to happen in a batch. */
 313                         fprintf(stderr,
 314                             "Incompatible options specified for inc-recursive %s.\n",
 315                             read_batch ? "batch file" : "connection");
 316                         exit_cleanup(RERR_SYNTAX);
 317                 }
 318                 use_safe_inc_flist = (compat_flags & CF_SAFE_FLIST) || protocol_version >= 31;
 319                 need_messages_from_generator = 1;
 320                 if (compat_flags & CF_INPLACE_PARTIAL_DIR)
 321                         inplace_partial = 1;
 322 #ifdef CAN_SET_SYMLINK_TIMES
 323         } else if (!am_sender) {
 324                 receiver_symlink_times = 1;
 325 #endif
 326         }
 327
 328         if (need_unsorted_flist && (!am_sender || inc_recurse))
 329                 unsort_ndx = ++file_extra_cnt;
 330
 331         if (partial_dir && *partial_dir != '/' && (!am_server || local_server)) {
 332                 int rflags = FILTRULE_NO_PREFIXES | FILTRULE_DIRECTORY;
 333                 if (!am_sender || protocol_version >= 30)
 334                         rflags |= FILTRULE_PERISHABLE;
 335                 parse_filter_str(&filter_list, partial_dir, rule_template(rflags), 0);
 336         }
 337
 338
 339 #ifdef ICONV_OPTION
 340         if (protect_args && files_from) {
 341                 if (am_sender)
 342                         filesfrom_convert = filesfrom_host && ic_send != (iconv_t)-1;
 343                 else
 344                         filesfrom_convert = !filesfrom_host && ic_recv != (iconv_t)-1;
 345         }
 346 #endif
 347
 348         if (am_server) {
 349                 if (!checksum_seed)
 350                         checksum_seed = time(NULL) ^ (getpid() << 6);
 351                 write_int(f_out, checksum_seed);
 352         } else {
 353                 checksum_seed = read_int(f_in);
 354         }
 355
 356         init_flist();
 357 }