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 extern int am_server;
  25 extern int am_sender;
  26 extern int local_server;
  27 extern int inplace;
  28 extern int recurse;
  29 extern int use_qsort;
  30 extern int allow_inc_recurse;
  31 extern int preallocate_files;
  32 extern int append_mode;
  33 extern int fuzzy_basis;
  34 extern int read_batch;
  35 extern int write_batch;
  36 extern int delay_updates;
  37 extern int checksum_seed;
  38 extern int basis_dir_cnt;
  39 extern int prune_empty_dirs;
  40 extern int protocol_version;
  41 extern int protect_args;
  42 extern int preserve_uid;
  43 extern int preserve_gid;
  44 extern int preserve_atimes;
  45 extern int preserve_acls;
  46 extern int preserve_xattrs;
  47 extern int xfer_flags_as_varint;
  48 extern int need_messages_from_generator;
  49 extern int delete_mode, delete_before, delete_during, delete_after;
  50 extern int do_compression;
  51 extern int do_compression_level;
  52 extern char *shell_cmd;
  53 extern char *partial_dir;
  54 extern char *files_from;
  55 extern char *filesfrom_host;
  56 extern const char *checksum_choice;
  57 extern const char *compress_choice;
  58 extern filter_rule_list filter_list;
  59 extern int need_unsorted_flist;
  60 #ifdef ICONV_OPTION
  61 extern iconv_t ic_send, ic_recv;
  62 extern char *iconv_opt;
  63 #endif
  64 extern struct name_num_obj valid_checksums;
  65
  66 int remote_protocol = 0;
  67 int file_extra_cnt = 0; /* count of file-list extras that everyone gets */
  68 int inc_recurse = 0;
  69 int compat_flags = 0;
  70 int use_safe_inc_flist = 0;
  71 int want_xattr_optim = 0;
  72 int proper_seed_order = 0;
  73 int inplace_partial = 0;
  74 int do_negotiated_strings = 0;
  75
  76 /* These index values are for the file-list's extra-attribute array. */
  77 int pathname_ndx, depth_ndx, atimes_ndx, uid_ndx, gid_ndx, acls_ndx, xattrs_ndx, unsort_ndx;
  78
  79 int receiver_symlink_times = 0; /* receiver can set the time on a symlink */
  80 int sender_symlink_iconv = 0;   /* sender should convert symlink content */
  81
  82 #ifdef ICONV_OPTION
  83 int filesfrom_convert = 0;
  84 #endif
  85
  86 #define MAX_NSTR_STRLEN 256
  87
  88 struct name_num_obj valid_compressions = {
  89         "compress", NULL, NULL, 0, 0, {
  90 #ifdef SUPPORT_ZSTD
  91                 { CPRES_ZSTD, "zstd", NULL },
  92 #endif
  93 #ifdef SUPPORT_LZ4
  94                 { CPRES_LZ4, "lz4", NULL },
  95 #endif
  96                 { CPRES_ZLIBX, "zlibx", NULL },
  97                 { CPRES_ZLIB, "zlib", NULL },
  98                 { CPRES_NONE, "none", NULL },
  99                 { 0, NULL, NULL }
 100         }
 101 };
 102
 103 #define CF_INC_RECURSE   (1<<0)
 104 #define CF_SYMLINK_TIMES (1<<1)
 105 #define CF_SYMLINK_ICONV (1<<2)
 106 #define CF_SAFE_FLIST    (1<<3)
 107 #define CF_AVOID_XATTR_OPTIM (1<<4)
 108 #define CF_CHKSUM_SEED_FIX (1<<5)
 109 #define CF_INPLACE_PARTIAL_DIR (1<<6)
 110 #define CF_VARINT_FLIST_FLAGS (1<<7)
 111
 112 static const char *client_info;
 113
 114 /* The server makes sure that if either side only supports a pre-release
 115  * version of a protocol, that both sides must speak a compatible version
 116  * of that protocol for it to be advertised as available. */
 117 static void check_sub_protocol(void)
 118 {
 119         char *dot;
 120         int their_protocol, their_sub;
 121 #if SUBPROTOCOL_VERSION != 0
 122         int our_sub = protocol_version < PROTOCOL_VERSION ? 0 : SUBPROTOCOL_VERSION;
 123 #else
 124         int our_sub = 0;
 125 #endif
 126
 127         /* client_info starts with VER.SUB string if client is a pre-release. */
 128         if (!(their_protocol = atoi(client_info))
 129          || !(dot = strchr(client_info, '.'))
 130          || !(their_sub = atoi(dot+1))) {
 131 #if SUBPROTOCOL_VERSION != 0
 132                 if (our_sub)
 133                         protocol_version--;
 134 #endif
 135                 return;
 136         }
 137
 138         if (their_protocol < protocol_version) {
 139                 if (their_sub)
 140                         protocol_version = their_protocol - 1;
 141                 return;
 142         }
 143
 144         if (their_protocol > protocol_version)
 145                 their_sub = 0; /* 0 == final version of older protocol */
 146         if (their_sub != our_sub)
 147                 protocol_version--;
 148 }
 149
 150 void set_allow_inc_recurse(void)
 151 {
 152         client_info = shell_cmd ? shell_cmd : "";
 153
 154         if (!recurse || use_qsort)
 155                 allow_inc_recurse = 0;
 156         else if (!am_sender
 157          && (delete_before || delete_after
 158           || delay_updates || prune_empty_dirs))
 159                 allow_inc_recurse = 0;
 160         else if (am_server && !local_server
 161          && (strchr(client_info, 'i') == NULL))
 162                 allow_inc_recurse = 0;
 163 }
 164
 165 void parse_compress_choice(int final_call)
 166 {
 167         if (valid_compressions.negotiated_name)
 168                 do_compression = valid_compressions.negotiated_num;
 169         else if (compress_choice) {
 170                 struct name_num_item *nni = get_nni_by_name(&valid_compressions, compress_choice, -1);
 171                 if (!nni) {
 172                         rprintf(FERROR, "unknown compress name: %s\n", compress_choice);
 173                         exit_cleanup(RERR_UNSUPPORTED);
 174                 }
 175                 do_compression = nni->num;
 176                 if (am_server)
 177                         validate_choice_vs_env(do_compression, -1);
 178         } else if (do_compression)
 179                 do_compression = CPRES_ZLIB;
 180         else
 181                 do_compression = CPRES_NONE;
 182
 183         if (do_compression != CPRES_NONE && final_call)
 184                 init_compression_level(); /* There's a chance this might turn compression off! */
 185
 186         if (do_compression == CPRES_NONE)
 187                 compress_choice = NULL;
 188
 189         /* Snag the compression name for both write_batch's option output & the following debug output. */
 190         if (valid_compressions.negotiated_name)
 191                 compress_choice = valid_compressions.negotiated_name;
 192         else if (compress_choice == NULL) {
 193                 struct name_num_item *nni = get_nni_by_num(&valid_compressions, do_compression);
 194                 compress_choice = nni ? nni->name : "UNKNOWN";
 195         }
 196
 197         if (final_call && DEBUG_GTE(NSTR, am_server ? 3 : 1)
 198          && (do_compression != CPRES_NONE || do_compression_level != CLVL_NOT_SPECIFIED)) {
 199                 rprintf(FINFO, "%s%s compress: %s (level %d)\n",
 200                         am_server ? "Server" : "Client",
 201                         valid_compressions.negotiated_name ? " negotiated" : "",
 202                         compress_choice, do_compression_level);
 203         }
 204 }
 205
 206 struct name_num_item *get_nni_by_name(struct name_num_obj *nno, const char *name, int len)
 207 {
 208         struct name_num_item *nni;
 209
 210         if (len < 0)
 211                 len = strlen(name);
 212
 213         for (nni = nno->list; nni->name; nni++) {
 214                 if (strncasecmp(name, nni->name, len) == 0 && nni->name[len] == '\0')
 215                         return nni;
 216         }
 217
 218         return NULL;
 219 }
 220
 221 struct name_num_item *get_nni_by_num(struct name_num_obj *nno, int num)
 222 {
 223         struct name_num_item *nni;
 224
 225         for (nni = nno->list; nni->name; nni++) {
 226                 if (num == nni->num)
 227                         return nni;
 228         }
 229
 230         return NULL;
 231 }
 232
 233 static void init_nno_saw(struct name_num_obj *nno, int val)
 234 {
 235         struct name_num_item *nni;
 236         int cnt;
 237
 238         if (!nno->saw_len) {
 239                 for (nni = nno->list; nni->name; nni++) {
 240                         if (nni->num >= nno->saw_len)
 241                                 nno->saw_len = nni->num + 1;
 242                 }
 243         }
 244
 245         if (!nno->saw) {
 246                 nno->saw = new_array0(uchar, nno->saw_len);
 247
 248                 /* We'll take this opportunity to make sure that the main_name values are set right. */
 249                 for (cnt = 1, nni = nno->list; nni->name; nni++, cnt++) {
 250                         if (nno->saw[nni->num])
 251                                 nni->main_name = nno->list[nno->saw[nni->num]-1].name;
 252                         else
 253                                 nno->saw[nni->num] = cnt;
 254                 }
 255         }
 256
 257         memset(nno->saw, val, nno->saw_len);
 258 }
 259
 260 /* Simplify the user-provided string so that it contains valid names without any duplicates.
 261  * It also sets the "saw" flags to a 1-relative count of which name was seen first. */
 262 static int parse_nni_str(struct name_num_obj *nno, const char *from, char *tobuf, int tobuf_len)
 263 {
 264         char *to = tobuf, *tok = NULL;
 265         int cnt = 0;
 266
 267         while (1) {
 268                 if (*from == ' ' || !*from) {
 269                         if (tok) {
 270                                 struct name_num_item *nni = get_nni_by_name(nno, tok, to - tok);
 271                                 if (nni && !nno->saw[nni->num]) {
 272                                         nno->saw[nni->num] = ++cnt;
 273                                         if (nni->main_name) {
 274                                                 to = tok + strlcpy(tok, nni->main_name, tobuf_len - (tok - tobuf));
 275                                                 if (to - tobuf >= tobuf_len) {
 276                                                         to = tok - 1;
 277                                                         break;
 278                                                 }
 279                                         }
 280                                 } else
 281                                         to = tok - (tok != tobuf);
 282                                 tok = NULL;
 283                         }
 284                         if (!*from++)
 285                                 break;
 286                         continue;
 287                 }
 288                 if (!tok) {
 289                         if (to != tobuf)
 290                                 *to++ = ' ';
 291                         tok = to;
 292                 }
 293                 if (to - tobuf >= tobuf_len - 1) {
 294                         to = tok - (tok != tobuf);
 295                         break;
 296                 }
 297                 *to++ = *from++;
 298         }
 299         *to = '\0';
 300
 301         return to - tobuf;
 302 }
 303
 304 static void recv_negotiate_str(int f_in, struct name_num_obj *nno, char *tmpbuf, int len)
 305 {
 306         struct name_num_item *ret = NULL;
 307
 308         if (len < 0)
 309                 len = read_vstring(f_in, tmpbuf, MAX_NSTR_STRLEN);
 310
 311         if (DEBUG_GTE(NSTR, am_server ? 3 : 2)) {
 312                 if (am_server)
 313                         rprintf(FINFO, "Client %s list (on server): %s\n", nno->type, tmpbuf);
 314                 else
 315                         rprintf(FINFO, "Server %s list (on client): %s\n", nno->type, tmpbuf);
 316         }
 317
 318         if (len > 0) {
 319                 int best = nno->saw_len; /* We want best == 1 from the client list, so start with a big number. */
 320                 char *tok;
 321                 if (am_server) {
 322                         int j;
 323                         /* Since we're parsing client names, anything in our list that we parse first is #1. */
 324                         for (j = 0; j < nno->saw_len; j++) {
 325                                 if (nno->saw[j])
 326                                         nno->saw[j] = 1;
 327                         }
 328                 }
 329                 for (tok = strtok(tmpbuf, " \t"); tok; tok = strtok(NULL, " \t")) {
 330                         struct name_num_item *nni = get_nni_by_name(nno, tok, -1);
 331                         if (!nni || !nno->saw[nni->num] || best <= nno->saw[nni->num])
 332                                 continue;
 333                         ret = nni;
 334                         best = nno->saw[nni->num];
 335                         if (best == 1)
 336                                 break;
 337                 }
 338                 if (ret) {
 339                         free(nno->saw);
 340                         nno->saw = NULL;
 341                         nno->negotiated_name = ret->main_name ? ret->main_name : ret->name;
 342                         nno->negotiated_num = ret->num;
 343                         return;
 344                 }
 345         }
 346
 347         if (!am_server || !do_negotiated_strings)
 348                 rprintf(FERROR, "Failed to negotiate a %s choice.\n", nno->type);
 349         exit_cleanup(RERR_UNSUPPORTED);
 350 }
 351
 352 /* If num2 < 0 then the caller is checking compress values, otherwise checksum values. */
 353 void validate_choice_vs_env(int num1, int num2)
 354 {
 355         struct name_num_obj *nno = num2 < 0 ? &valid_compressions : &valid_checksums;
 356         const char *list_str = getenv(num2 < 0 ? "RSYNC_COMPRESS_LIST" : "RSYNC_CHECKSUM_LIST");
 357         char tmpbuf[MAX_NSTR_STRLEN];
 358
 359         if (!list_str || !*list_str)
 360                 return;
 361
 362         init_nno_saw(nno, 0);
 363         parse_nni_str(nno, list_str, tmpbuf, MAX_NSTR_STRLEN);
 364
 365         if (num2 >= 0) /* If "md4" is in the env list, all the old MD4 choices are OK too. */
 366                 nno->saw[CSUM_MD4_ARCHAIC] = nno->saw[CSUM_MD4_BUSTED] = nno->saw[CSUM_MD4_OLD] = nno->saw[CSUM_MD4];
 367
 368         if (!nno->saw[num1] || (num2 >= 0 && !nno->saw[num2])) {
 369                 rprintf(FERROR, "Your --%s-choice value (%s) was refused by the server.\n",
 370                         num2 < 0 ? "compress" : "checksum", num2 < 0 ? compress_choice : checksum_choice);
 371                 exit_cleanup(RERR_UNSUPPORTED);
 372         }
 373
 374         free(nno->saw);
 375         nno->saw = NULL;
 376 }
 377
 378 /* The saw buffer is initialized and used to store ordinal values from 1 to N
 379  * for the order of the args in the array.  If dup_markup == '\0', duplicates
 380  * are removed otherwise the char is prefixed to the duplicate term and, if it
 381  * is an opening paren/bracket/brace, the matching closing char is suffixed.
 382  * "none" is removed on the client side unless dup_markup != '\0'. */
 383 int get_default_nno_list(struct name_num_obj *nno, char *to_buf, int to_buf_len, char dup_markup)
 384 {
 385         struct name_num_item *nni;
 386         int len = 0, cnt = 0;
 387         char delim = '\0', post_delim;
 388
 389         switch (dup_markup) {
 390         case '(': post_delim = ')'; break;
 391         case '[': post_delim = ']'; break;
 392         case '{': post_delim = '}'; break;
 393         default: post_delim = '\0'; break;
 394         }
 395
 396         init_nno_saw(nno, 0);
 397
 398         for (nni = nno->list, len = 0; nni->name; nni++) {
 399                 if (nni->main_name) {
 400                         if (!dup_markup)
 401                                 continue;
 402                         delim = dup_markup;
 403                 }
 404                 if (nni->num == 0 && !am_server && !dup_markup)
 405                         continue;
 406                 if (len)
 407                         to_buf[len++]= ' ';
 408                 if (delim) {
 409                         to_buf[len++]= delim;
 410                         delim = post_delim;
 411                 }
 412                 len += strlcpy(to_buf+len, nni->name, to_buf_len - len);
 413                 if (len >= to_buf_len - 3)
 414                         exit_cleanup(RERR_UNSUPPORTED); /* IMPOSSIBLE... */
 415                 if (delim) {
 416                         to_buf[len++]= delim;
 417                         delim = '\0';
 418                 }
 419                 nno->saw[nni->num] = ++cnt;
 420         }
 421
 422         return len;
 423 }
 424
 425 static void send_negotiate_str(int f_out, struct name_num_obj *nno, const char *env_name)
 426 {
 427         char tmpbuf[MAX_NSTR_STRLEN];
 428         const char *list_str = getenv(env_name);
 429         int len;
 430
 431         if (list_str && *list_str) {
 432                 init_nno_saw(nno, 0);
 433                 len = parse_nni_str(nno, list_str, tmpbuf, MAX_NSTR_STRLEN);
 434                 if (!len)
 435                         len = strlcpy(tmpbuf, "FAIL", MAX_NSTR_STRLEN);
 436                 list_str = tmpbuf;
 437         } else
 438                 list_str = NULL;
 439
 440         if (!list_str || !*list_str)
 441                 len = get_default_nno_list(nno, tmpbuf, MAX_NSTR_STRLEN, '\0');
 442
 443         if (DEBUG_GTE(NSTR, am_server ? 3 : 2)) {
 444                 if (am_server)
 445                         rprintf(FINFO, "Server %s list (on server): %s\n", nno->type, tmpbuf);
 446                 else
 447                         rprintf(FINFO, "Client %s list (on client): %s\n", nno->type, tmpbuf);
 448         }
 449
 450         if (local_server) {
 451                 /* A local server doesn't bother to send/recv the strings, it just constructs
 452                  * and parses the same string on both sides. */
 453                 recv_negotiate_str(-1, nno, tmpbuf, len);
 454         } else if (do_negotiated_strings) {
 455                 /* Each side sends their list of valid names to the other side and then both sides
 456                  * pick the first name in the client's list that is also in the server's list. */
 457                 write_vstring(f_out, tmpbuf, len);
 458         }
 459 }
 460
 461 static void negotiate_the_strings(int f_in, int f_out)
 462 {
 463         /* We send all the negotiation strings before we start to read them to help avoid a slow startup. */
 464
 465         if (!checksum_choice)
 466                 send_negotiate_str(f_out, &valid_checksums, "RSYNC_CHECKSUM_LIST");
 467
 468         if (do_compression && !compress_choice)
 469                 send_negotiate_str(f_out, &valid_compressions, "RSYNC_COMPRESS_LIST");
 470
 471         if (valid_checksums.saw) {
 472                 char tmpbuf[MAX_NSTR_STRLEN];
 473                 int len;
 474                 if (do_negotiated_strings)
 475                         len = -1;
 476                 else
 477                         len = strlcpy(tmpbuf, protocol_version >= 30 ? "md5" : "md4", MAX_NSTR_STRLEN);
 478                 recv_negotiate_str(f_in, &valid_checksums, tmpbuf, len);
 479         }
 480
 481         if (valid_compressions.saw) {
 482                 char tmpbuf[MAX_NSTR_STRLEN];
 483                 int len;
 484                 if (do_negotiated_strings)
 485                         len = -1;
 486                 else
 487                         len = strlcpy(tmpbuf, "zlib", MAX_NSTR_STRLEN);
 488                 recv_negotiate_str(f_in, &valid_compressions, tmpbuf, len);
 489         }
 490
 491         /* If the other side is too old to negotiate, the above steps just made sure that
 492          * the env didn't disallow the old algorithm. Mark things as non-negotiated. */
 493         if (!do_negotiated_strings)
 494                 valid_checksums.negotiated_name = valid_compressions.negotiated_name = NULL;
 495 }
 496
 497 void setup_protocol(int f_out,int f_in)
 498 {
 499         assert(file_extra_cnt == 0);
 500         assert(EXTRA64_CNT == 2 || EXTRA64_CNT == 1);
 501
 502         /* All int64 values must be set first so that they are guaranteed to be
 503          * aligned for direct int64-pointer memory access. */
 504         if (preserve_atimes)
 505                 atimes_ndx = (file_extra_cnt += EXTRA64_CNT);
 506         if (am_sender) /* This is most likely in the in64 union as well. */
 507                 pathname_ndx = (file_extra_cnt += PTR_EXTRA_CNT);
 508         else
 509                 depth_ndx = ++file_extra_cnt;
 510         if (preserve_uid)
 511                 uid_ndx = ++file_extra_cnt;
 512         if (preserve_gid)
 513                 gid_ndx = ++file_extra_cnt;
 514         if (preserve_acls && !am_sender)
 515                 acls_ndx = ++file_extra_cnt;
 516         if (preserve_xattrs)
 517                 xattrs_ndx = ++file_extra_cnt;
 518
 519         if (am_server)
 520                 set_allow_inc_recurse();
 521
 522         if (remote_protocol == 0) {
 523                 if (am_server && !local_server)
 524                         check_sub_protocol();
 525                 if (!read_batch)
 526                         write_int(f_out, protocol_version);
 527                 remote_protocol = read_int(f_in);
 528                 if (protocol_version > remote_protocol)
 529                         protocol_version = remote_protocol;
 530         }
 531         if (read_batch && remote_protocol > protocol_version) {
 532                 rprintf(FERROR, "The protocol version in the batch file is too new (%d > %d).\n",
 533                         remote_protocol, protocol_version);
 534                 exit_cleanup(RERR_PROTOCOL);
 535         }
 536
 537         if (DEBUG_GTE(PROTO, 1)) {
 538                 rprintf(FINFO, "(%s) Protocol versions: remote=%d, negotiated=%d\n",
 539                         am_server? "Server" : "Client", remote_protocol, protocol_version);
 540         }
 541         if (remote_protocol < MIN_PROTOCOL_VERSION
 542          || remote_protocol > MAX_PROTOCOL_VERSION) {
 543                 rprintf(FERROR,"protocol version mismatch -- is your shell clean?\n");
 544                 rprintf(FERROR,"(see the rsync man page for an explanation)\n");
 545                 exit_cleanup(RERR_PROTOCOL);
 546         }
 547         if (remote_protocol < OLD_PROTOCOL_VERSION) {
 548                 rprintf(FINFO,"%s is very old version of rsync, upgrade recommended.\n",
 549                         am_server? "Client" : "Server");
 550         }
 551         if (protocol_version < MIN_PROTOCOL_VERSION) {
 552                 rprintf(FERROR, "--protocol must be at least %d on the %s.\n",
 553                         MIN_PROTOCOL_VERSION, am_server? "Server" : "Client");
 554                 exit_cleanup(RERR_PROTOCOL);
 555         }
 556         if (protocol_version > PROTOCOL_VERSION) {
 557                 rprintf(FERROR, "--protocol must be no more than %d on the %s.\n",
 558                         PROTOCOL_VERSION, am_server? "Server" : "Client");
 559                 exit_cleanup(RERR_PROTOCOL);
 560         }
 561         if (read_batch)
 562                 check_batch_flags();
 563
 564 #ifndef SUPPORT_PREALLOCATION
 565         if (preallocate_files && !am_sender) {
 566                 rprintf(FERROR, "preallocation is not supported on this %s\n",
 567                         am_server ? "Server" : "Client");
 568                 exit_cleanup(RERR_SYNTAX);
 569         }
 570 #endif
 571
 572         if (protocol_version < 30) {
 573                 if (append_mode == 1)
 574                         append_mode = 2;
 575                 if (preserve_acls && !local_server) {
 576                         rprintf(FERROR,
 577                                 "--acls requires protocol 30 or higher"
 578                                 " (negotiated %d).\n",
 579                                 protocol_version);
 580                         exit_cleanup(RERR_PROTOCOL);
 581                 }
 582                 if (preserve_xattrs && !local_server) {
 583                         rprintf(FERROR,
 584                                 "--xattrs requires protocol 30 or higher"
 585                                 " (negotiated %d).\n",
 586                                 protocol_version);
 587                         exit_cleanup(RERR_PROTOCOL);
 588                 }
 589         }
 590
 591         if (delete_mode && !(delete_before+delete_during+delete_after)) {
 592                 if (protocol_version < 30)
 593                         delete_before = 1;
 594                 else
 595                         delete_during = 1;
 596         }
 597
 598         if (protocol_version < 29) {
 599                 if (fuzzy_basis) {
 600                         rprintf(FERROR,
 601                                 "--fuzzy requires protocol 29 or higher"
 602                                 " (negotiated %d).\n",
 603                                 protocol_version);
 604                         exit_cleanup(RERR_PROTOCOL);
 605                 }
 606
 607                 if (basis_dir_cnt && inplace) {
 608                         rprintf(FERROR,
 609                                 "%s with --inplace requires protocol 29 or higher"
 610                                 " (negotiated %d).\n",
 611                                 alt_dest_opt(0), protocol_version);
 612                         exit_cleanup(RERR_PROTOCOL);
 613                 }
 614
 615                 if (basis_dir_cnt > 1) {
 616                         rprintf(FERROR,
 617                                 "Using more than one %s option requires protocol"
 618                                 " 29 or higher (negotiated %d).\n",
 619                                 alt_dest_opt(0), protocol_version);
 620                         exit_cleanup(RERR_PROTOCOL);
 621                 }
 622
 623                 if (prune_empty_dirs) {
 624                         rprintf(FERROR,
 625                                 "--prune-empty-dirs requires protocol 29 or higher"
 626                                 " (negotiated %d).\n",
 627                                 protocol_version);
 628                         exit_cleanup(RERR_PROTOCOL);
 629                 }
 630         } else if (protocol_version >= 30) {
 631                 if (am_server) {
 632                         compat_flags = allow_inc_recurse ? CF_INC_RECURSE : 0;
 633 #ifdef CAN_SET_SYMLINK_TIMES
 634                         compat_flags |= CF_SYMLINK_TIMES;
 635 #endif
 636 #ifdef ICONV_OPTION
 637                         compat_flags |= CF_SYMLINK_ICONV;
 638 #endif
 639                         if (local_server || strchr(client_info, 'f') != NULL)
 640                                 compat_flags |= CF_SAFE_FLIST;
 641                         if (local_server || strchr(client_info, 'x') != NULL)
 642                                 compat_flags |= CF_AVOID_XATTR_OPTIM;
 643                         if (local_server || strchr(client_info, 'C') != NULL)
 644                                 compat_flags |= CF_CHKSUM_SEED_FIX;
 645                         if (local_server || strchr(client_info, 'I') != NULL)
 646                                 compat_flags |= CF_INPLACE_PARTIAL_DIR;
 647                         if (local_server || strchr(client_info, 'v') != NULL) {
 648                                 if (!write_batch || protocol_version >= 30) {
 649                                         do_negotiated_strings = 1;
 650                                         compat_flags |= CF_VARINT_FLIST_FLAGS;
 651                                 }
 652                         }
 653                         if (strchr(client_info, 'V') != NULL) { /* Support a pre-release 'V' that got superseded */
 654                                 if (!write_batch)
 655                                         compat_flags |= CF_VARINT_FLIST_FLAGS;
 656                                 write_byte(f_out, compat_flags);
 657                         } else
 658                                 write_varint(f_out, compat_flags);
 659                 } else { /* read_varint() is compatible with the older write_byte() when the 0x80 bit isn't on. */
 660                         compat_flags = read_varint(f_in);
 661                         if  (compat_flags & CF_VARINT_FLIST_FLAGS)
 662                                 do_negotiated_strings = 1;
 663                 }
 664                 /* The inc_recurse var MUST be set to 0 or 1. */
 665                 inc_recurse = compat_flags & CF_INC_RECURSE ? 1 : 0;
 666                 want_xattr_optim = protocol_version >= 31 && !(compat_flags & CF_AVOID_XATTR_OPTIM);
 667                 proper_seed_order = compat_flags & CF_CHKSUM_SEED_FIX ? 1 : 0;
 668                 xfer_flags_as_varint = compat_flags & CF_VARINT_FLIST_FLAGS ? 1 : 0;
 669                 if (am_sender) {
 670                         receiver_symlink_times = am_server
 671                             ? strchr(client_info, 'L') != NULL
 672                             : !!(compat_flags & CF_SYMLINK_TIMES);
 673                 }
 674 #ifdef CAN_SET_SYMLINK_TIMES
 675                 else
 676                         receiver_symlink_times = 1;
 677 #endif
 678 #ifdef ICONV_OPTION
 679                 sender_symlink_iconv = iconv_opt && (am_server
 680                     ? local_server || strchr(client_info, 's') != NULL
 681                     : !!(compat_flags & CF_SYMLINK_ICONV));
 682 #endif
 683                 if (inc_recurse && !allow_inc_recurse) {
 684                         /* This should only be able to happen in a batch. */
 685                         fprintf(stderr,
 686                                 "Incompatible options specified for inc-recursive %s.\n",
 687                                 read_batch ? "batch file" : "connection");
 688                         exit_cleanup(RERR_SYNTAX);
 689                 }
 690                 use_safe_inc_flist = (compat_flags & CF_SAFE_FLIST) || protocol_version >= 31;
 691                 need_messages_from_generator = 1;
 692                 if (compat_flags & CF_INPLACE_PARTIAL_DIR)
 693                         inplace_partial = 1;
 694 #ifdef CAN_SET_SYMLINK_TIMES
 695         } else if (!am_sender) {
 696                 receiver_symlink_times = 1;
 697 #endif
 698         }
 699
 700         if (need_unsorted_flist && (!am_sender || inc_recurse))
 701                 unsort_ndx = ++file_extra_cnt;
 702
 703         if (partial_dir && *partial_dir != '/' && (!am_server || local_server)) {
 704                 int rflags = FILTRULE_NO_PREFIXES | FILTRULE_DIRECTORY;
 705                 if (!am_sender || protocol_version >= 30)
 706                         rflags |= FILTRULE_PERISHABLE;
 707                 parse_filter_str(&filter_list, partial_dir, rule_template(rflags), 0);
 708         }
 709
 710
 711 #ifdef ICONV_OPTION
 712         if (protect_args && files_from) {
 713                 if (am_sender)
 714                         filesfrom_convert = filesfrom_host && ic_send != (iconv_t)-1;
 715                 else
 716                         filesfrom_convert = !filesfrom_host && ic_recv != (iconv_t)-1;
 717         }
 718 #endif
 719
 720         negotiate_the_strings(f_in, f_out);
 721
 722         if (am_server) {
 723                 if (!checksum_seed)
 724                         checksum_seed = time(NULL) ^ (getpid() << 6);
 725                 write_int(f_out, checksum_seed);
 726         } else {
 727                 checksum_seed = read_int(f_in);
 728         }
 729
 730         parse_checksum_choice(1); /* Sets checksum_type & xfersum_type */
 731         parse_compress_choice(1); /* Sets do_compression */
 732
 733         if (write_batch && !am_server)
 734                 write_batch_shell_file();
 735
 736         init_flist();
 737 }