citadel/server/internet_addressing.c

   1 // This file contains functions which handle the mapping of Internet addresses
   2 // to users on the Citadel system.
   3 //
   4 // Copyright (c) 1987-2022 by the citadel.org team
   5 //
   6 // This program is open source software.  Use, duplication, or disclosure
   7 // is subject to the terms of the GNU General Public License, version 3.
   8
   9 #include "sysdep.h"
  10 #include <stdlib.h>
  11 #include <unistd.h>
  12 #include <stdio.h>
  13 #include <fcntl.h>
  14 #include <ctype.h>
  15 #include <signal.h>
  16 #include <pwd.h>
  17 #include <errno.h>
  18 #include <sys/types.h>
  19 #include <time.h>
  20 #include <sys/wait.h>
  21 #include <string.h>
  22 #include <limits.h>
  23 #include <libcitadel.h>
  24 #include "citadel.h"
  25 #include "server.h"
  26 #include "sysdep_decls.h"
  27 #include "citserver.h"
  28 #include "support.h"
  29 #include "config.h"
  30 #include "msgbase.h"
  31 #include "internet_addressing.h"
  32 #include "user_ops.h"
  33 #include "room_ops.h"
  34 #include "parsedate.h"
  35 #include "database.h"
  36 #include "ctdl_module.h"
  37
  38
  39
  40 char *inetcfg = NULL;
  41
  42 // Return nonzero if the supplied name is an alias for this host.
  43 int CtdlHostAlias(char *fqdn) {
  44         int config_lines;
  45         int i;
  46         char buf[256];
  47         char host[256], type[256];
  48         int found = 0;
  49
  50         if (fqdn == NULL)                                       return(hostalias_nomatch);
  51         if (IsEmptyStr(fqdn))                                   return(hostalias_nomatch);
  52         if (!strcasecmp(fqdn, "localhost"))                     return(hostalias_localhost);
  53         if (!strcasecmp(fqdn, CtdlGetConfigStr("c_fqdn")))      return(hostalias_localhost);
  54         if (!strcasecmp(fqdn, CtdlGetConfigStr("c_nodename")))  return(hostalias_localhost);
  55         if (inetcfg == NULL)                                    return(hostalias_nomatch);
  56
  57         config_lines = num_tokens(inetcfg, '\n');
  58         for (i=0; i<config_lines; ++i) {
  59                 extract_token(buf, inetcfg, i, '\n', sizeof buf);
  60                 extract_token(host, buf, 0, '|', sizeof host);
  61                 extract_token(type, buf, 1, '|', sizeof type);
  62
  63                 found = 0;
  64
  65                 // Process these in a specific order, in case there are multiple matches.
  66                 // We want localhost to override masq, for example.
  67
  68                 if ( (!strcasecmp(type, "masqdomain")) && (!strcasecmp(fqdn, host))) {
  69                         found = hostalias_masq;
  70                 }
  71
  72                 if ( (!strcasecmp(type, "localhost")) && (!strcasecmp(fqdn, host))) {
  73                         found = hostalias_localhost;
  74                 }
  75
  76                 // "directory" used to be a distributed version of "localhost" but they're both the same now
  77                 if ( (!strcasecmp(type, "directory")) && (!strcasecmp(fqdn, host))) {
  78                         found = hostalias_localhost;
  79                 }
  80
  81                 if (found) return(found);
  82         }
  83         return(hostalias_nomatch);
  84 }
  85
  86
  87 // Determine whether a given Internet address belongs to the current user
  88 int CtdlIsMe(char *addr, int addr_buf_len) {
  89         struct recptypes *recp;
  90         int i;
  91
  92         recp = validate_recipients(addr, NULL, 0);
  93         if (recp == NULL) return(0);
  94
  95         if (recp->num_local == 0) {
  96                 free_recipients(recp);
  97                 return(0);
  98         }
  99
 100         for (i=0; i<recp->num_local; ++i) {
 101                 extract_token(addr, recp->recp_local, i, '|', addr_buf_len);
 102                 if (!strcasecmp(addr, CC->user.fullname)) {
 103                         free_recipients(recp);
 104                         return(1);
 105                 }
 106         }
 107
 108         free_recipients(recp);
 109         return(0);
 110 }
 111
 112
 113 // If the last item in a list of recipients was truncated to a partial address,
 114 // remove it completely in order to avoid choking library functions.
 115 void sanitize_truncated_recipient(char *str) {
 116         if (!str) return;
 117         if (num_tokens(str, ',') < 2) return;
 118
 119         int len = strlen(str);
 120         if (len < 900) return;
 121         if (len > 998) str[998] = 0;
 122
 123         char *cptr = strrchr(str, ',');
 124         if (!cptr) return;
 125
 126         char *lptr = strchr(cptr, '<');
 127         char *rptr = strchr(cptr, '>');
 128
 129         if ( (lptr) && (rptr) && (rptr > lptr) ) return;
 130
 131         *cptr = 0;
 132 }
 133
 134
 135 // This function is self explanatory.
 136 // (What can I say, I'm in a weird mood today...)
 137 void remove_any_whitespace_to_the_left_or_right_of_at_symbol(char *name) {
 138         char *ptr;
 139         if (!name) return;
 140
 141         for (ptr=name; *ptr; ++ptr) {
 142                 while ( (isspace(*ptr)) && (*(ptr+1)=='@') ) {
 143                         strcpy(ptr, ptr+1);
 144                         if (ptr > name) --ptr;
 145                 }
 146                 while ( (*ptr=='@') && (*(ptr+1)!=0) && (isspace(*(ptr+1))) ) {
 147                         strcpy(ptr+1, ptr+2);
 148                 }
 149         }
 150 }
 151
 152
 153 // values that can be returned by expand_aliases()
 154 enum {
 155         EA_ERROR,               // Can't send message due to bad address
 156         EA_MULTIPLE,            // Alias expanded into multiple recipients -- run me again!
 157         EA_LOCAL,               // Local message, do no network processing
 158         EA_INTERNET,            // Convert msg and send as Internet mail
 159         EA_SKIP                 // This recipient has been invalidated -- skip it!
 160 };
 161
 162
 163 // Process alias and routing info for email addresses
 164 int expand_aliases(char *name, char *aliases) {
 165         int a;
 166         char aaa[SIZ];
 167         int at = 0;
 168
 169         if (aliases) {
 170                 int num_aliases = num_tokens(aliases, '\n');
 171                 for (a=0; a<num_aliases; ++a) {
 172                         extract_token(aaa, aliases, a, '\n', sizeof aaa);
 173                         char *bar = strchr(aaa, '|');
 174                         if (bar) {
 175                                 bar[0] = 0;
 176                                 ++bar;
 177                                 striplt(aaa);
 178                                 striplt(bar);
 179                                 if ( (!IsEmptyStr(aaa)) && (!strcasecmp(name, aaa)) ) {
 180                                         syslog(LOG_DEBUG, "internet_addressing: global alias <%s> to <%s>", name, bar);
 181                                         strcpy(name, bar);
 182                                 }
 183                         }
 184                 }
 185                 if (strchr(name, ',')) {
 186                         return(EA_MULTIPLE);
 187                 }
 188         }
 189
 190         char original_name[256];                                // Now go for the regular aliases
 191         safestrncpy(original_name, name, sizeof original_name);
 192
 193         // should these checks still be here, or maybe move them to split_recps() ?
 194         striplt(name);
 195         remove_any_whitespace_to_the_left_or_right_of_at_symbol(name);
 196         stripallbut(name, '<', '>');
 197
 198         // Hit the email address directory
 199         if (CtdlDirectoryLookup(aaa, name, sizeof aaa) == 0) {
 200                 strcpy(name, aaa);
 201         }
 202
 203         if (strcasecmp(original_name, name)) {
 204                 syslog(LOG_INFO, "internet_addressing: directory alias <%s> to <%s>", original_name, name);
 205         }
 206
 207         // Change "user @ xxx" to "user" if xxx is an alias for this host
 208         for (a=0; name[a] != '\0'; ++a) {
 209                 if (name[a] == '@') {
 210                         if (CtdlHostAlias(&name[a+1]) == hostalias_localhost) {
 211                                 name[a] = 0;
 212                                 syslog(LOG_DEBUG, "internet_addressing: host is local, recipient is <%s>", name);
 213                                 break;
 214                         }
 215                 }
 216         }
 217
 218         // Is this a local or remote recipient?
 219         at = haschar(name, '@');
 220         if (at == 0) {
 221                 return(EA_LOCAL);                       // no @'s = local address
 222         }
 223         else if (at == 1) {
 224                 return(EA_INTERNET);                    // one @ = internet address
 225         }
 226         else {
 227                 return(EA_ERROR);                       // more than one @ = badly formed address
 228         }
 229 }
 230
 231
 232 // Return a supplied list of email addresses as an array, removing superfluous information and syntax.
 233 // If an existing Array is supplied as "append_to" it will do so; otherwise a new Array is allocated.
 234 Array *split_recps(char *addresses, Array *append_to) {
 235
 236         if (IsEmptyStr(addresses)) {            // nothing supplied, nothing returned
 237                 return(NULL);
 238         }
 239
 240         // Copy the supplied address list into our own memory space, because we are going to modify it.
 241         char *a = strdup(addresses);
 242         if (a == NULL) {
 243                 syslog(LOG_ERR, "internet_addressing: malloc() failed: %m");
 244                 return(NULL);
 245         }
 246
 247         // Strip out anything in double quotes
 248         char *l = NULL;
 249         char *r = NULL;
 250         do {
 251                 l = strchr(a, '\"');
 252                 r = strrchr(a, '\"');
 253                 if (r > l) {
 254                         strcpy(l, r+1);
 255                 }
 256         } while (r > l);
 257
 258         // Transform all qualifying delimiters to commas
 259         char *t;
 260         for (t=a; t[0]; ++t) {
 261                 if ((t[0]==';') || (t[0]=='|')) {
 262                         t[0]=',';
 263                 }
 264         }
 265
 266         // Tokenize the recipients into an array.  No single recipient should be larger than 256 bytes.
 267         Array *recipients_array = NULL;
 268         if (append_to) {
 269                 recipients_array = append_to;                   // Append to an existing array of recipients
 270         }
 271         else {
 272                 recipients_array = array_new(256);              // This is a new array of recipients
 273         }
 274
 275         int num_addresses = num_tokens(a, ',');
 276         int i;
 277         for (i=0; i<num_addresses; ++i) {
 278                 char this_address[256];
 279                 extract_token(this_address, a, i, ',', sizeof this_address);
 280                 striplt(this_address);                          // strip leading and trailing whitespace
 281                 stripout(this_address, '(', ')');               // remove any portion in parentheses
 282                 stripallbut(this_address, '<', '>');            // if angle brackets are present, keep only what is inside them
 283                 if (!IsEmptyStr(this_address)) {
 284                         array_append(recipients_array, this_address);
 285                 }
 286         }
 287
 288         free(a);                                                // We don't need this buffer anymore.
 289         return(recipients_array);                               // Return the completed array to the caller.
 290 }
 291
 292
 293 // Validate recipients, count delivery types and errors, and handle aliasing
 294 //
 295 // Returns 0 if all addresses are ok, ret->num_error = -1 if no addresses
 296 // were specified, or the number of addresses found invalid.
 297 //
 298 // Caller needs to free the result using free_recipients()
 299 //
 300 struct recptypes *validate_recipients(char *supplied_recipients, const char *RemoteIdentifier, int Flags) {
 301         struct recptypes *ret;
 302         char *recipients = NULL;
 303         char append[SIZ];
 304         long len;
 305         int mailtype;
 306         int invalid;
 307         struct ctdluser tempUS;
 308         struct ctdlroom original_room;
 309         int err = 0;
 310         char errmsg[SIZ];
 311         char *org_recp;
 312         char this_recp[256];
 313
 314         ret = (struct recptypes *) malloc(sizeof(struct recptypes));                    // Initialize
 315         if (ret == NULL) return(NULL);
 316         memset(ret, 0, sizeof(struct recptypes));                                       // set all values to null/zero
 317
 318         if (supplied_recipients == NULL) {
 319                 recipients = strdup("");
 320         }
 321         else {
 322                 recipients = strdup(supplied_recipients);
 323         }
 324
 325         len = strlen(recipients) + 1024;                                                // allocate memory
 326         ret->errormsg = malloc(len);
 327         ret->recp_local = malloc(len);
 328         ret->recp_internet = malloc(len);
 329         ret->recp_room = malloc(len);
 330         ret->display_recp = malloc(len);
 331         ret->recp_orgroom = malloc(len);
 332
 333         ret->errormsg[0] = 0;
 334         ret->recp_local[0] = 0;
 335         ret->recp_internet[0] = 0;
 336         ret->recp_room[0] = 0;
 337         ret->recp_orgroom[0] = 0;
 338         ret->display_recp[0] = 0;
 339         ret->recptypes_magic = RECPTYPES_MAGIC;
 340
 341         Array *recp_array = split_recps(supplied_recipients, NULL);
 342
 343         char *aliases = CtdlGetSysConfig(GLOBAL_ALIASES);                               // First hit the Global Alias Table
 344
 345         int r;
 346         for (r=0; (recp_array && r<array_len(recp_array)); ++r) {
 347                 org_recp = (char *)array_get_element_at(recp_array, r);
 348                 strncpy(this_recp, org_recp, sizeof this_recp);
 349
 350                 int i;
 351                 for (i=0; i<3; ++i) {                                           // pass three times through the aliaser
 352                         mailtype = expand_aliases(this_recp, aliases);
 353
 354                         // If an alias expanded to multiple recipients, strip off those recipients and append them
 355                         // to the end of the array.  This loop will hit those again when it gets there.
 356                         if (mailtype == EA_MULTIPLE) {
 357                                 recp_array = split_recps(this_recp, recp_array);
 358                         }
 359                 }
 360
 361                 // This loop searches for duplicate recipients in the final list and marks them to be skipped.
 362                 int j;
 363                 for (j=0; j<r; ++j) {
 364                         if (!strcasecmp(this_recp, (char *)array_get_element_at(recp_array, j) )) {
 365                                 mailtype = EA_SKIP;
 366                         }
 367                 }
 368
 369                 syslog(LOG_DEBUG, "Recipient #%d of type %d is <%s>", r, mailtype, this_recp);
 370                 invalid = 0;
 371                 errmsg[0] = 0;
 372                 switch(mailtype) {
 373                 case EA_LOCAL:                                  // There are several types of "local" recipients.
 374
 375                         // Old BBS conventions require mail to "sysop" to go somewhere.  Send it to the admin room.
 376                         if (!strcasecmp(this_recp, "sysop")) {
 377                                 ++ret->num_room;
 378                                 strcpy(this_recp, CtdlGetConfigStr("c_aideroom"));
 379                                 if (!IsEmptyStr(ret->recp_room)) {
 380                                         strcat(ret->recp_room, "|");
 381                                 }
 382                                 strcat(ret->recp_room, this_recp);
 383                         }
 384
 385                         // This handles rooms which can receive posts via email.
 386                         else if (!strncasecmp(this_recp, "room_", 5)) {
 387                                 original_room = CC->room;                               // Remember where we parked
 388
 389                                 char mail_to_room[ROOMNAMELEN];
 390                                 char *m;
 391                                 strncpy(mail_to_room, &this_recp[5], sizeof mail_to_room);
 392                                 for (m = mail_to_room; *m; ++m) {
 393                                         if (m[0] == '_') m[0]=' ';
 394                                 }
 395                                 if (!CtdlGetRoom(&CC->room, mail_to_room)) {            // Find the room they asked for
 396
 397                                         err = CtdlDoIHavePermissionToPostInThisRoom(    // check for write permissions to room
 398                                                 errmsg,
 399                                                 sizeof errmsg,
 400                                                 Flags,
 401                                                 0                                       // 0 means "this is not a reply"
 402                                         );
 403                                         if (err) {
 404                                                 ++ret->num_error;
 405                                                 invalid = 1;
 406                                         }
 407                                         else {
 408                                                 ++ret->num_room;
 409                                                 if (!IsEmptyStr(ret->recp_room)) {
 410                                                         strcat(ret->recp_room, "|");
 411                                                 }
 412                                                 strcat(ret->recp_room, CC->room.QRname);
 413
 414                                                 if (!IsEmptyStr(ret->recp_orgroom)) {
 415                                                         strcat(ret->recp_orgroom, "|");
 416                                                 }
 417                                                 strcat(ret->recp_orgroom, this_recp);
 418
 419                                         }
 420                                 }
 421                                 else {                                                  // no such room exists
 422                                         ++ret->num_error;
 423                                         invalid = 1;
 424                                 }
 425
 426                                 // Restore this session's original room location.
 427                                 CC->room = original_room;
 428
 429                         }
 430
 431                         // This handles the most common case, which is mail to a user's inbox.
 432                         else if (CtdlGetUser(&tempUS, this_recp) == 0) {
 433                                 ++ret->num_local;
 434                                 strcpy(this_recp, tempUS.fullname);
 435                                 if (!IsEmptyStr(ret->recp_local)) {
 436                                         strcat(ret->recp_local, "|");
 437                                 }
 438                                 strcat(ret->recp_local, this_recp);
 439                         }
 440
 441                         // No match for this recipient
 442                         else {
 443                                 ++ret->num_error;
 444                                 invalid = 1;
 445                         }
 446                         break;
 447                 case EA_INTERNET:
 448                         // Yes, you're reading this correctly: if the target domain points back to the local system,
 449                         // the address is invalid.  That's because if the address were valid, we would have
 450                         // already translated it to a local address by now.
 451                         if (IsDirectory(this_recp, 0)) {
 452                                 ++ret->num_error;
 453                                 invalid = 1;
 454                         }
 455                         else {
 456                                 ++ret->num_internet;
 457                                 if (!IsEmptyStr(ret->recp_internet)) {
 458                                         strcat(ret->recp_internet, "|");
 459                                 }
 460                                 strcat(ret->recp_internet, this_recp);
 461                         }
 462                         break;
 463                 case EA_MULTIPLE:
 464                 case EA_SKIP:
 465                         // no action required, anything in this slot has already been processed elsewhere
 466                         break;
 467                 case EA_ERROR:
 468                         ++ret->num_error;
 469                         invalid = 1;
 470                         break;
 471                 }
 472                 if (invalid) {
 473                         if (IsEmptyStr(errmsg)) {
 474                                 snprintf(append, sizeof append, "Invalid recipient: %s", this_recp);
 475                         }
 476                         else {
 477                                 snprintf(append, sizeof append, "%s", errmsg);
 478                         }
 479                         if ( (strlen(ret->errormsg) + strlen(append) + 3) < SIZ) {
 480                                 if (!IsEmptyStr(ret->errormsg)) {
 481                                         strcat(ret->errormsg, "; ");
 482                                 }
 483                                 strcat(ret->errormsg, append);
 484                         }
 485                 }
 486                 else {
 487                         if (IsEmptyStr(ret->display_recp)) {
 488                                 strcpy(append, this_recp);
 489                         }
 490                         else {
 491                                 snprintf(append, sizeof append, ", %s", this_recp);
 492                         }
 493                         if ( (strlen(ret->display_recp)+strlen(append)) < SIZ) {
 494                                 strcat(ret->display_recp, append);
 495                         }
 496                 }
 497         }
 498
 499         if (aliases != NULL) {          // ok, we're done with the global alias list now
 500                 free(aliases);
 501         }
 502
 503         if ( (ret->num_local + ret->num_internet + ret->num_room + ret->num_error) == 0) {
 504                 ret->num_error = (-1);
 505                 strcpy(ret->errormsg, "No recipients specified.");
 506         }
 507
 508         syslog(LOG_DEBUG, "internet_addressing: validate_recipients() = %d local, %d room, %d SMTP, %d error",
 509                 ret->num_local, ret->num_room, ret->num_internet, ret->num_error
 510         );
 511
 512         free(recipients);
 513         if (recp_array) {
 514                 array_free(recp_array);
 515         }
 516
 517         return(ret);
 518 }
 519
 520
 521 // Destructor for recptypes
 522 void free_recipients(struct recptypes *valid) {
 523
 524         if (valid == NULL) {
 525                 return;
 526         }
 527
 528         if (valid->recptypes_magic != RECPTYPES_MAGIC) {
 529                 syslog(LOG_ERR, "internet_addressing: attempt to call free_recipients() on some other data type!");
 530                 abort();
 531         }
 532
 533         if (valid->errormsg != NULL)            free(valid->errormsg);
 534         if (valid->recp_local != NULL)          free(valid->recp_local);
 535         if (valid->recp_internet != NULL)       free(valid->recp_internet);
 536         if (valid->recp_room != NULL)           free(valid->recp_room);
 537         if (valid->recp_orgroom != NULL)        free(valid->recp_orgroom);
 538         if (valid->display_recp != NULL)        free(valid->display_recp);
 539         if (valid->bounce_to != NULL)           free(valid->bounce_to);
 540         if (valid->envelope_from != NULL)       free(valid->envelope_from);
 541         if (valid->sending_room != NULL)        free(valid->sending_room);
 542         free(valid);
 543 }
 544
 545
 546 char *qp_encode_email_addrs(char *source) {
 547         char *user, *node, *name;
 548         const char headerStr[] = "=?UTF-8?Q?";
 549         char *Encoded;
 550         char *EncodedName;
 551         char *nPtr;
 552         int need_to_encode = 0;
 553         long SourceLen;
 554         long EncodedMaxLen;
 555         long nColons = 0;
 556         long *AddrPtr;
 557         long *AddrUtf8;
 558         long nAddrPtrMax = 50;
 559         long nmax;
 560         int InQuotes = 0;
 561         int i, n;
 562
 563         if (source == NULL) return source;
 564         if (IsEmptyStr(source)) return source;
 565         syslog(LOG_DEBUG, "internet_addressing: qp_encode_email_addrs <%s>", source);
 566
 567         AddrPtr = malloc (sizeof (long) * nAddrPtrMax);
 568         AddrUtf8 = malloc (sizeof (long) * nAddrPtrMax);
 569         memset(AddrUtf8, 0, sizeof (long) * nAddrPtrMax);
 570         *AddrPtr = 0;
 571         i = 0;
 572         while (!IsEmptyStr (&source[i])) {
 573                 if (nColons >= nAddrPtrMax){
 574                         long *ptr;
 575
 576                         ptr = (long *) malloc(sizeof (long) * nAddrPtrMax * 2);
 577                         memcpy (ptr, AddrPtr, sizeof (long) * nAddrPtrMax);
 578                         free (AddrPtr), AddrPtr = ptr;
 579
 580                         ptr = (long *) malloc(sizeof (long) * nAddrPtrMax * 2);
 581                         memset(&ptr[nAddrPtrMax], 0, sizeof (long) * nAddrPtrMax);
 582
 583                         memcpy (ptr, AddrUtf8, sizeof (long) * nAddrPtrMax);
 584                         free (AddrUtf8), AddrUtf8 = ptr;
 585                         nAddrPtrMax *= 2;
 586                 }
 587                 if (((unsigned char) source[i] < 32) || ((unsigned char) source[i] > 126)) {
 588                         need_to_encode = 1;
 589                         AddrUtf8[nColons] = 1;
 590                 }
 591                 if (source[i] == '"') {
 592                         InQuotes = !InQuotes;
 593                 }
 594                 if (!InQuotes && source[i] == ',') {
 595                         AddrPtr[nColons] = i;
 596                         nColons++;
 597                 }
 598                 i++;
 599         }
 600         if (need_to_encode == 0) {
 601                 free(AddrPtr);
 602                 free(AddrUtf8);
 603                 return source;
 604         }
 605
 606         SourceLen = i;
 607         EncodedMaxLen = nColons * (sizeof(headerStr) + 3) + SourceLen * 3;
 608         Encoded = (char*) malloc (EncodedMaxLen);
 609
 610         for (i = 0; i < nColons; i++) {
 611                 source[AddrPtr[i]++] = '\0';
 612         }
 613         // TODO: if libidn, this might get larger
 614         user = malloc(SourceLen + 1);
 615         node = malloc(SourceLen + 1);
 616         name = malloc(SourceLen + 1);
 617
 618         nPtr = Encoded;
 619         *nPtr = '\0';
 620         for (i = 0; i < nColons && nPtr != NULL; i++) {
 621                 nmax = EncodedMaxLen - (nPtr - Encoded);
 622                 if (AddrUtf8[i]) {
 623                         process_rfc822_addr(&source[AddrPtr[i]], user, node, name);
 624                         // TODO: libIDN here !
 625                         if (IsEmptyStr(name)) {
 626                                 n = snprintf(nPtr, nmax, (i==0)?"%s@%s" : ",%s@%s", user, node);
 627                         }
 628                         else {
 629                                 EncodedName = rfc2047encode(name, strlen(name));
 630                                 n = snprintf(nPtr, nmax, (i==0)?"%s <%s@%s>" : ",%s <%s@%s>", EncodedName, user, node);
 631                                 free(EncodedName);
 632                         }
 633                 }
 634                 else {
 635                         n = snprintf(nPtr, nmax, (i==0)?"%s" : ",%s", &source[AddrPtr[i]]);
 636                 }
 637                 if (n > 0 )
 638                         nPtr += n;
 639                 else {
 640                         char *ptr, *nnPtr;
 641                         ptr = (char*) malloc(EncodedMaxLen * 2);
 642                         memcpy(ptr, Encoded, EncodedMaxLen);
 643                         nnPtr = ptr + (nPtr - Encoded), nPtr = nnPtr;
 644                         free(Encoded), Encoded = ptr;
 645                         EncodedMaxLen *= 2;
 646                         i--; // do it once more with properly lengthened buffer
 647                 }
 648         }
 649         for (i = 0; i < nColons; i++)
 650                 source[--AddrPtr[i]] = ',';
 651
 652         free(user);
 653         free(node);
 654         free(name);
 655         free(AddrUtf8);
 656         free(AddrPtr);
 657         return Encoded;
 658 }
 659
 660
 661 // Unfold a multi-line field into a single line, removing multi-whitespaces
 662 void unfold_rfc822_field(char **field, char **FieldEnd)
 663 {
 664         int quote = 0;
 665         char *pField = *field;
 666         char *sField;
 667         char *pFieldEnd = *FieldEnd;
 668
 669         while (isspace(*pField))
 670                 pField++;
 671         // remove leading/trailing whitespace
 672         ;
 673
 674         while (isspace(*pFieldEnd))
 675                 pFieldEnd --;
 676
 677         *FieldEnd = pFieldEnd;
 678         // convert non-space whitespace to spaces, and remove double blanks
 679         for (sField = *field = pField;
 680              sField < pFieldEnd;
 681              pField++, sField++)
 682         {
 683                 if ((*sField=='\r') || (*sField=='\n'))
 684                 {
 685                         int offset = 1;
 686                         while ( ( (*(sField + offset) == '\r') || (*(sField + offset) == '\n' )) && (sField + offset < pFieldEnd) ) {
 687                                 offset ++;
 688                         }
 689                         sField += offset;
 690                         *pField = *sField;
 691                 }
 692                 else {
 693                         if (*sField=='\"') quote = 1 - quote;
 694                         if (!quote) {
 695                                 if (isspace(*sField)) {
 696                                         *pField = ' ';
 697                                         pField++;
 698                                         sField++;
 699
 700                                         while ((sField < pFieldEnd) &&
 701                                                isspace(*sField))
 702                                                 sField++;
 703                                         *pField = *sField;
 704                                 }
 705                                 else *pField = *sField;
 706                         }
 707                         else *pField = *sField;
 708                 }
 709         }
 710         *pField = '\0';
 711         *FieldEnd = pField - 1;
 712 }
 713
 714
 715 // Split an RFC822-style address into userid, host, and full name
 716 void process_rfc822_addr(const char *rfc822, char *user, char *node, char *name) {
 717         int a;
 718
 719         strcpy(user, "");
 720         strcpy(node, CtdlGetConfigStr("c_fqdn"));
 721         strcpy(name, "");
 722
 723         if (rfc822 == NULL) return;
 724
 725         // extract full name - first, it's From minus <userid>
 726         strcpy(name, rfc822);
 727         stripout(name, '<', '>');
 728
 729         // and anything to the right of a @
 730         for (a = 0; name[a] != '\0'; ++a) {
 731                 if (name[a] == '@') {
 732                         name[a] = 0;
 733                         break;
 734                 }
 735         }
 736
 737         // but if there are parentheses, that changes the rules...
 738         if ((haschar(rfc822, '(') == 1) && (haschar(rfc822, ')') == 1)) {
 739                 strcpy(name, rfc822);
 740                 stripallbut(name, '(', ')');
 741         }
 742
 743         // but if there are a set of quotes, that supersedes everything
 744         if (haschar(rfc822, 34) == 2) {
 745                 strcpy(name, rfc822);
 746                 while ((!IsEmptyStr(name)) && (name[0] != 34)) {
 747                         strcpy(&name[0], &name[1]);
 748                 }
 749                 strcpy(&name[0], &name[1]);
 750                 for (a = 0; name[a] != '\0'; ++a)
 751                         if (name[a] == 34) {
 752                                 name[a] = 0;
 753                                 break;
 754                         }
 755         }
 756         // extract user id
 757         strcpy(user, rfc822);
 758
 759         // first get rid of anything in parens
 760         stripout(user, '(', ')');
 761
 762         // if there's a set of angle brackets, strip it down to that
 763         if ((haschar(user, '<') == 1) && (haschar(user, '>') == 1)) {
 764                 stripallbut(user, '<', '>');
 765         }
 766
 767         // and anything to the right of a @
 768         for (a = 0; user[a] != '\0'; ++a) {
 769                 if (user[a] == '@') {
 770                         user[a] = 0;
 771                         break;
 772                 }
 773         }
 774
 775         // extract node name
 776         strcpy(node, rfc822);
 777
 778         // first get rid of anything in parens
 779         stripout(node, '(', ')');
 780
 781         // if there's a set of angle brackets, strip it down to that
 782         if ((haschar(node, '<') == 1) && (haschar(node, '>') == 1)) {
 783                 stripallbut(node, '<', '>');
 784         }
 785
 786         // If no node specified, tack ours on instead
 787         if (haschar(node, '@') == 0) {
 788                 strcpy(node, CtdlGetConfigStr("c_nodename"));
 789         }
 790         else {
 791                 // strip anything to the left of a @
 792                 while ((!IsEmptyStr(node)) && (haschar(node, '@') > 0)) {
 793                         strcpy(node, &node[1]);
 794                 }
 795         }
 796
 797         // strip leading and trailing spaces in all strings
 798         striplt(user);
 799         striplt(node);
 800         striplt(name);
 801
 802         // If we processed a string that had the address in angle brackets
 803         // but no name outside the brackets, we now have an empty name.  In
 804         // this case, use the user portion of the address as the name.
 805         if ((IsEmptyStr(name)) && (!IsEmptyStr(user))) {
 806                 strcpy(name, user);
 807         }
 808 }
 809
 810
 811 // convert_field() is a helper function for convert_internet_message().
 812 // Given start/end positions for an rfc822 field, it converts it to a Citadel
 813 // field if it wants to, and unfolds it if necessary.
 814 //
 815 // Returns 1 if the field was converted and inserted into the Citadel message
 816 // structure, implying that the source field should be removed from the
 817 // message text.
 818 int convert_field(struct CtdlMessage *msg, const char *beg, const char *end) {
 819         char *key, *value, *valueend;
 820         long len;
 821         const char *pos;
 822         int i;
 823         const char *colonpos = NULL;
 824         int processed = 0;
 825         char user[1024];
 826         char node[1024];
 827         char name[1024];
 828         char addr[1024];
 829         time_t parsed_date;
 830         long valuelen;
 831
 832         for (pos = end; pos >= beg; pos--) {
 833                 if (*pos == ':') colonpos = pos;
 834         }
 835
 836         if (colonpos == NULL) return(0);        /* no colon? not a valid header line */
 837
 838         len = end - beg;
 839         key = malloc(len + 2);
 840         memcpy(key, beg, len + 1);
 841         key[len] = '\0';
 842         valueend = key + len;
 843         * ( key + (colonpos - beg) ) = '\0';
 844         value = &key[(colonpos - beg) + 1];
 845         // printf("Header: [%s]\nValue: [%s]\n", key, value);
 846         unfold_rfc822_field(&value, &valueend);
 847         valuelen = valueend - value + 1;
 848         // printf("UnfoldedValue: [%s]\n", value);
 849
 850         // Here's the big rfc822-to-citadel loop.
 851
 852         // Date/time is converted into a unix timestamp.  If the conversion
 853         // fails, we replace it with the time the message arrived locally.
 854         if (!strcasecmp(key, "Date")) {
 855                 parsed_date = parsedate(value);
 856                 if (parsed_date < 0L) parsed_date = time(NULL);
 857
 858                 if (CM_IsEmpty(msg, eTimestamp))
 859                         CM_SetFieldLONG(msg, eTimestamp, parsed_date);
 860                 processed = 1;
 861         }
 862
 863         else if (!strcasecmp(key, "From")) {
 864                 process_rfc822_addr(value, user, node, name);
 865                 syslog(LOG_DEBUG, "internet_addressing: converted to <%s@%s> (%s)", user, node, name);
 866                 snprintf(addr, sizeof(addr), "%s@%s", user, node);
 867                 if (CM_IsEmpty(msg, eAuthor) && !IsEmptyStr(name)) {
 868                         CM_SetField(msg, eAuthor, name, -1);
 869                 }
 870                 if (CM_IsEmpty(msg, erFc822Addr) && !IsEmptyStr(addr)) {
 871                         CM_SetField(msg, erFc822Addr, addr, -1);
 872                 }
 873                 processed = 1;
 874         }
 875
 876         else if (!strcasecmp(key, "Subject")) {
 877                 if (CM_IsEmpty(msg, eMsgSubject))
 878                         CM_SetField(msg, eMsgSubject, value, valuelen);
 879                 processed = 1;
 880         }
 881
 882         else if (!strcasecmp(key, "List-ID")) {
 883                 if (CM_IsEmpty(msg, eListID))
 884                         CM_SetField(msg, eListID, value, valuelen);
 885                 processed = 1;
 886         }
 887
 888         else if (!strcasecmp(key, "To")) {
 889                 if (CM_IsEmpty(msg, eRecipient))
 890                         CM_SetField(msg, eRecipient, value, valuelen);
 891                 processed = 1;
 892         }
 893
 894         else if (!strcasecmp(key, "CC")) {
 895                 if (CM_IsEmpty(msg, eCarbonCopY))
 896                         CM_SetField(msg, eCarbonCopY, value, valuelen);
 897                 processed = 1;
 898         }
 899
 900         else if (!strcasecmp(key, "Message-ID")) {
 901                 if (!CM_IsEmpty(msg, emessageId)) {
 902                         syslog(LOG_WARNING, "internet_addressing: duplicate message id");
 903                 }
 904                 else {
 905                         char *pValue;
 906                         long pValueLen;
 907
 908                         pValue = value;
 909                         pValueLen = valuelen;
 910                         // Strip angle brackets
 911                         while (haschar(pValue, '<') > 0) {
 912                                 pValue ++;
 913                                 pValueLen --;
 914                         }
 915
 916                         for (i = 0; i <= pValueLen; ++i)
 917                                 if (pValue[i] == '>') {
 918                                         pValueLen = i;
 919                                         break;
 920                                 }
 921
 922                         CM_SetField(msg, emessageId, pValue, pValueLen);
 923                 }
 924
 925                 processed = 1;
 926         }
 927
 928         else if (!strcasecmp(key, "Return-Path")) {
 929                 if (CM_IsEmpty(msg, eMessagePath))
 930                         CM_SetField(msg, eMessagePath, value, valuelen);
 931                 processed = 1;
 932         }
 933
 934         else if (!strcasecmp(key, "Envelope-To")) {
 935                 if (CM_IsEmpty(msg, eenVelopeTo))
 936                         CM_SetField(msg, eenVelopeTo, value, valuelen);
 937                 processed = 1;
 938         }
 939
 940         else if (!strcasecmp(key, "References")) {
 941                 CM_SetField(msg, eWeferences, value, valuelen);
 942                 processed = 1;
 943         }
 944
 945         else if (!strcasecmp(key, "Reply-To")) {
 946                 CM_SetField(msg, eReplyTo, value, valuelen);
 947                 processed = 1;
 948         }
 949
 950         else if (!strcasecmp(key, "In-reply-to")) {
 951                 if (CM_IsEmpty(msg, eWeferences)) // References: supersedes In-reply-to:
 952                         CM_SetField(msg, eWeferences, value, valuelen);
 953                 processed = 1;
 954         }
 955
 956
 957
 958         // Clean up and move on.
 959         free(key);      // Don't free 'value', it's actually the same buffer
 960         return processed;
 961 }
 962
 963
 964 // Convert RFC822 references format (References) to Citadel references format (Weferences)
 965 void convert_references_to_wefewences(char *str) {
 966         int bracket_nesting = 0;
 967         char *ptr = str;
 968         char *moveptr = NULL;
 969         char ch;
 970
 971         while(*ptr) {
 972                 ch = *ptr;
 973                 if (ch == '>') {
 974                         --bracket_nesting;
 975                         if (bracket_nesting < 0) bracket_nesting = 0;
 976                 }
 977                 if ((ch == '>') && (bracket_nesting == 0) && (*(ptr+1)) && (ptr>str) ) {
 978                         *ptr = '|';
 979                         ++ptr;
 980                 }
 981                 else if (bracket_nesting > 0) {
 982                         ++ptr;
 983                 }
 984                 else {
 985                         moveptr = ptr;
 986                         while (*moveptr) {
 987                                 *moveptr = *(moveptr+1);
 988                                 ++moveptr;
 989                         }
 990                 }
 991                 if (ch == '<') ++bracket_nesting;
 992         }
 993
 994 }
 995
 996
 997 // Convert an RFC822 message (headers + body) to a CtdlMessage structure.
 998 // NOTE: the supplied buffer becomes part of the CtdlMessage structure, and
 999 // will be deallocated when CM_Free() is called.  Therefore, the
1000 // supplied buffer should be DEREFERENCED.  It should not be freed or used
1001 // again.
1002 struct CtdlMessage *convert_internet_message(char *rfc822) {
1003         StrBuf *RFCBuf = NewStrBufPlain(rfc822, -1);
1004         free (rfc822);
1005         return convert_internet_message_buf(&RFCBuf);
1006 }
1007
1008
1009 struct CtdlMessage *convert_internet_message_buf(StrBuf **rfc822)
1010 {
1011         struct CtdlMessage *msg;
1012         const char *pos, *beg, *end, *totalend;
1013         int done, alldone = 0;
1014         int converted;
1015         StrBuf *OtherHeaders;
1016
1017         msg = malloc(sizeof(struct CtdlMessage));
1018         if (msg == NULL) return msg;
1019
1020         memset(msg, 0, sizeof(struct CtdlMessage));
1021         msg->cm_magic = CTDLMESSAGE_MAGIC;      // self check
1022         msg->cm_anon_type = 0;                  // never anonymous
1023         msg->cm_format_type = FMT_RFC822;       // internet message
1024
1025         pos = ChrPtr(*rfc822);
1026         totalend = pos + StrLength(*rfc822);
1027         done = 0;
1028         OtherHeaders = NewStrBufPlain(NULL, StrLength(*rfc822));
1029
1030         while (!alldone) {
1031
1032                 /* Locate beginning and end of field, keeping in mind that
1033                  * some fields might be multiline
1034                  */
1035                 end = beg = pos;
1036
1037                 while ((end < totalend) &&
1038                        (end == beg) &&
1039                        (done == 0) )
1040                 {
1041
1042                         if ( (*pos=='\n') && ((*(pos+1))!=0x20) && ((*(pos+1))!=0x09) )
1043                         {
1044                                 end = pos;
1045                         }
1046
1047                         /* done with headers? */
1048                         if ((*pos=='\n') &&
1049                             ( (*(pos+1)=='\n') ||
1050                               (*(pos+1)=='\r')) )
1051                         {
1052                                 alldone = 1;
1053                         }
1054
1055                         if (pos >= (totalend - 1) )
1056                         {
1057                                 end = pos;
1058                                 done = 1;
1059                         }
1060
1061                         ++pos;
1062
1063                 }
1064
1065                 /* At this point we have a field.  Are we interested in it? */
1066                 converted = convert_field(msg, beg, end);
1067
1068                 /* Strip the field out of the RFC822 header if we used it */
1069                 if (!converted) {
1070                         StrBufAppendBufPlain(OtherHeaders, beg, end - beg, 0);
1071                         StrBufAppendBufPlain(OtherHeaders, HKEY("\n"), 0);
1072                 }
1073
1074                 /* If we've hit the end of the message, bail out */
1075                 if (pos >= totalend)
1076                         alldone = 1;
1077         }
1078         StrBufAppendBufPlain(OtherHeaders, HKEY("\n"), 0);
1079         if (pos < totalend)
1080                 StrBufAppendBufPlain(OtherHeaders, pos, totalend - pos, 0);
1081         FreeStrBuf(rfc822);
1082         CM_SetAsFieldSB(msg, eMesageText, &OtherHeaders);
1083
1084         /* Follow-up sanity checks... */
1085
1086         /* If there's no timestamp on this message, set it to now. */
1087         if (CM_IsEmpty(msg, eTimestamp)) {
1088                 CM_SetFieldLONG(msg, eTimestamp, time(NULL));
1089         }
1090
1091         /* If a W (references, or rather, Wefewences) field is present, we
1092          * have to convert it from RFC822 format to Citadel format.
1093          */
1094         if (!CM_IsEmpty(msg, eWeferences)) {
1095                 /// todo: API!
1096                 convert_references_to_wefewences(msg->cm_fields[eWeferences]);
1097         }
1098
1099         return msg;
1100 }
1101
1102
1103 /*
1104  * Look for a particular header field in an RFC822 message text.  If the
1105  * requested field is found, it is unfolded (if necessary) and returned to
1106  * the caller.  The field name is stripped out, leaving only its contents.
1107  * The caller is responsible for freeing the returned buffer.  If the requested
1108  * field is not present, or anything else goes wrong, it returns NULL.
1109  */
1110 char *rfc822_fetch_field(const char *rfc822, const char *fieldname) {
1111         char *fieldbuf = NULL;
1112         const char *end_of_headers;
1113         const char *field_start;
1114         const char *ptr;
1115         char *cont;
1116         char fieldhdr[SIZ];
1117
1118         /* Should never happen, but sometimes we get stupid */
1119         if (rfc822 == NULL) return(NULL);
1120         if (fieldname == NULL) return(NULL);
1121
1122         snprintf(fieldhdr, sizeof fieldhdr, "%s:", fieldname);
1123
1124         /* Locate the end of the headers, so we don't run past that point */
1125         end_of_headers = cbmstrcasestr(rfc822, "\n\r\n");
1126         if (end_of_headers == NULL) {
1127                 end_of_headers = cbmstrcasestr(rfc822, "\n\n");
1128         }
1129         if (end_of_headers == NULL) return (NULL);
1130
1131         field_start = cbmstrcasestr(rfc822, fieldhdr);
1132         if (field_start == NULL) return(NULL);
1133         if (field_start > end_of_headers) return(NULL);
1134
1135         fieldbuf = malloc(SIZ);
1136         strcpy(fieldbuf, "");
1137
1138         ptr = field_start;
1139         ptr = cmemreadline(ptr, fieldbuf, SIZ-strlen(fieldbuf) );
1140         while ( (isspace(ptr[0])) && (ptr < end_of_headers) ) {
1141                 strcat(fieldbuf, " ");
1142                 cont = &fieldbuf[strlen(fieldbuf)];
1143                 ptr = cmemreadline(ptr, cont, SIZ-strlen(fieldbuf) );
1144                 striplt(cont);
1145         }
1146
1147         strcpy(fieldbuf, &fieldbuf[strlen(fieldhdr)]);
1148         striplt(fieldbuf);
1149
1150         return(fieldbuf);
1151 }
1152
1153
1154 /*****************************************************************************
1155  *                      DIRECTORY MANAGEMENT FUNCTIONS                       *
1156  *****************************************************************************/
1157
1158 /*
1159  * Generate the index key for an Internet e-mail address to be looked up
1160  * in the database.
1161  */
1162 void directory_key(char *key, char *addr) {
1163         int i;
1164         int keylen = 0;
1165
1166         for (i=0; !IsEmptyStr(&addr[i]); ++i) {
1167                 if (!isspace(addr[i])) {
1168                         key[keylen++] = tolower(addr[i]);
1169                 }
1170         }
1171         key[keylen++] = 0;
1172
1173         syslog(LOG_DEBUG, "internet_addressing: directory key is <%s>", key);
1174 }
1175
1176
1177 /*
1178  * Return nonzero if the supplied address is in one of "our" domains
1179  */
1180 int IsDirectory(char *addr, int allow_masq_domains) {
1181         char domain[256];
1182         int h;
1183
1184         extract_token(domain, addr, 1, '@', sizeof domain);
1185         striplt(domain);
1186
1187         h = CtdlHostAlias(domain);
1188
1189         if ( (h == hostalias_masq) && allow_masq_domains)
1190                 return(1);
1191
1192         if (h == hostalias_localhost) {
1193                 return(1);
1194         }
1195         else {
1196                 return(0);
1197         }
1198 }
1199
1200
1201 /*
1202  * Add an Internet e-mail address to the directory for a user
1203  */
1204 int CtdlDirectoryAddUser(char *internet_addr, char *citadel_addr) {
1205         char key[SIZ];
1206
1207         if (IsDirectory(internet_addr, 0) == 0) {
1208                 return 0;
1209         }
1210         syslog(LOG_DEBUG, "internet_addressing: create directory entry: %s --> %s", internet_addr, citadel_addr);
1211         directory_key(key, internet_addr);
1212         cdb_store(CDB_DIRECTORY, key, strlen(key), citadel_addr, strlen(citadel_addr)+1 );
1213         return 1;
1214 }
1215
1216
1217 /*
1218  * Delete an Internet e-mail address from the directory.
1219  *
1220  * (NOTE: we don't actually use or need the citadel_addr variable; it's merely
1221  * here because the callback API expects to be able to send it.)
1222  */
1223 int CtdlDirectoryDelUser(char *internet_addr, char *citadel_addr) {
1224         char key[SIZ];
1225
1226         syslog(LOG_DEBUG, "internet_addressing: delete directory entry: %s --> %s", internet_addr, citadel_addr);
1227         directory_key(key, internet_addr);
1228         return cdb_delete(CDB_DIRECTORY, key, strlen(key) ) == 0;
1229 }
1230
1231
1232 /*
1233  * Look up an Internet e-mail address in the directory.
1234  * On success: returns 0, and Citadel address stored in 'target'
1235  * On failure: returns nonzero
1236  */
1237 int CtdlDirectoryLookup(char *target, char *internet_addr, size_t targbuflen) {
1238         struct cdbdata *cdbrec;
1239         char key[SIZ];
1240
1241         /* Dump it in there unchanged, just for kicks */
1242         if (target != NULL) {
1243                 safestrncpy(target, internet_addr, targbuflen);
1244         }
1245
1246         /* Only do lookups for addresses with hostnames in them */
1247         if (num_tokens(internet_addr, '@') != 2) return(-1);
1248
1249         /* Only do lookups for domains in the directory */
1250         if (IsDirectory(internet_addr, 0) == 0) return(-1);
1251
1252         directory_key(key, internet_addr);
1253         cdbrec = cdb_fetch(CDB_DIRECTORY, key, strlen(key) );
1254         if (cdbrec != NULL) {
1255                 if (target != NULL) {
1256                         safestrncpy(target, cdbrec->ptr, targbuflen);
1257                 }
1258                 cdb_free(cdbrec);
1259                 return(0);
1260         }
1261
1262         return(-1);
1263 }
1264
1265
1266 /*
1267  * Harvest any email addresses that someone might want to have in their
1268  * "collected addresses" book.
1269  */
1270 char *harvest_collected_addresses(struct CtdlMessage *msg) {
1271         char *coll = NULL;
1272         char addr[256];
1273         char user[256], node[256], name[256];
1274         int is_harvestable;
1275         int i, j, h;
1276         eMsgField field = 0;
1277
1278         if (msg == NULL) return(NULL);
1279
1280         is_harvestable = 1;
1281         strcpy(addr, "");
1282         if (!CM_IsEmpty(msg, eAuthor)) {
1283                 strcat(addr, msg->cm_fields[eAuthor]);
1284         }
1285         if (!CM_IsEmpty(msg, erFc822Addr)) {
1286                 strcat(addr, " <");
1287                 strcat(addr, msg->cm_fields[erFc822Addr]);
1288                 strcat(addr, ">");
1289                 if (IsDirectory(msg->cm_fields[erFc822Addr], 0)) {
1290                         is_harvestable = 0;
1291                 }
1292         }
1293
1294         if (is_harvestable) {
1295                 coll = strdup(addr);
1296         }
1297         else {
1298                 coll = strdup("");
1299         }
1300
1301         if (coll == NULL) return(NULL);
1302
1303         /* Scan both the R (To) and Y (CC) fields */
1304         for (i = 0; i < 2; ++i) {
1305                 if (i == 0) field = eRecipient;
1306                 if (i == 1) field = eCarbonCopY;
1307
1308                 if (!CM_IsEmpty(msg, field)) {
1309                         for (j=0; j<num_tokens(msg->cm_fields[field], ','); ++j) {
1310                                 extract_token(addr, msg->cm_fields[field], j, ',', sizeof addr);
1311                                 if (strstr(addr, "=?") != NULL) {
1312                                         utf8ify_rfc822_string(addr);
1313                                 }
1314                                 process_rfc822_addr(addr, user, node, name);
1315                                 h = CtdlHostAlias(node);
1316                                 if (h != hostalias_localhost) {
1317                                         coll = realloc(coll, strlen(coll) + strlen(addr) + 4);
1318                                         if (coll == NULL) return(NULL);
1319                                         if (!IsEmptyStr(coll)) {
1320                                                 strcat(coll, ",");
1321                                         }
1322                                         striplt(addr);
1323                                         strcat(coll, addr);
1324                                 }
1325                         }
1326                 }
1327         }
1328
1329         if (IsEmptyStr(coll)) {
1330                 free(coll);
1331                 return(NULL);
1332         }
1333         return(coll);
1334 }
1335
1336
1337 /*
1338  * Helper function for CtdlRebuildDirectoryIndex()
1339  */
1340 void CtdlRebuildDirectoryIndex_backend(char *username, void *data) {
1341
1342         int j = 0;
1343         struct ctdluser usbuf;
1344
1345         if (CtdlGetUser(&usbuf, username) != 0) {
1346                 return;
1347         }
1348
1349         if ( (!IsEmptyStr(usbuf.fullname)) && (!IsEmptyStr(usbuf.emailaddrs)) ) {
1350                 for (j=0; j<num_tokens(usbuf.emailaddrs, '|'); ++j) {
1351                         char one_email[512];
1352                         extract_token(one_email, usbuf.emailaddrs, j, '|', sizeof one_email);
1353                         CtdlDirectoryAddUser(one_email, usbuf.fullname);
1354                 }
1355         }
1356 }
1357
1358
1359 /*
1360  * Initialize the directory database (erasing anything already there)
1361  */
1362 void CtdlRebuildDirectoryIndex(void) {
1363         syslog(LOG_INFO, "internet_addressing: rebuilding email address directory index");
1364         cdb_trunc(CDB_DIRECTORY);
1365         ForEachUser(CtdlRebuildDirectoryIndex_backend, NULL);
1366 }
1367
1368
1369 // Configure Internet email addresses for a user account, updating the Directory Index in the process
1370 void CtdlSetEmailAddressesForUser(char *requested_user, char *new_emailaddrs) {
1371         struct ctdluser usbuf;
1372         int i;
1373         char buf[SIZ];
1374
1375         if (CtdlGetUserLock(&usbuf, requested_user) != 0) {     // We can lock because the DirectoryIndex functions don't lock.
1376                 return;                                         // Silently fail here if the specified user does not exist.
1377         }
1378
1379         syslog(LOG_DEBUG, "internet_addressing: setting email addresses for <%s> to <%s>", usbuf.fullname, new_emailaddrs);
1380
1381         // Delete all of the existing directory index records for the user (easier this way)
1382         for (i=0; i<num_tokens(usbuf.emailaddrs, '|'); ++i) {
1383                 extract_token(buf, usbuf.emailaddrs, i, '|', sizeof buf);
1384                 CtdlDirectoryDelUser(buf, requested_user);
1385         }
1386
1387         strcpy(usbuf.emailaddrs, new_emailaddrs);               // make it official.
1388
1389         // Index all of the new email addresses (they've already been sanitized)
1390         for (i=0; i<num_tokens(usbuf.emailaddrs, '|'); ++i) {
1391                 extract_token(buf, usbuf.emailaddrs, i, '|', sizeof buf);
1392                 CtdlDirectoryAddUser(buf, requested_user);
1393         }
1394
1395         CtdlPutUserLock(&usbuf);
1396 }
1397
1398
1399 /*
1400  * Auto-generate an Internet email address for a user account
1401  */
1402 void AutoGenerateEmailAddressForUser(struct ctdluser *user) {
1403         char synthetic_email_addr[1024];
1404         int i, j;
1405         int u = 0;
1406
1407         for (i=0; u==0; ++i) {
1408                 if (i == 0) {
1409                         // first try just converting the user name to lowercase and replacing spaces with underscores
1410                         snprintf(synthetic_email_addr, sizeof synthetic_email_addr, "%s@%s", user->fullname, CtdlGetConfigStr("c_fqdn"));
1411                         for (j=0; ((synthetic_email_addr[j] != '\0')&&(synthetic_email_addr[j] != '@')); j++) {
1412                                 synthetic_email_addr[j] = tolower(synthetic_email_addr[j]);
1413                                 if (!isalnum(synthetic_email_addr[j])) {
1414                                         synthetic_email_addr[j] = '_';
1415                                 }
1416                         }
1417                 }
1418                 else if (i == 1) {
1419                         // then try 'ctdl' followed by the user number
1420                         snprintf(synthetic_email_addr, sizeof synthetic_email_addr, "ctdl%08lx@%s", user->usernum, CtdlGetConfigStr("c_fqdn"));
1421                 }
1422                 else if (i > 1) {
1423                         // oof.  just keep trying other numbers until we find one
1424                         snprintf(synthetic_email_addr, sizeof synthetic_email_addr, "ctdl%08x@%s", i, CtdlGetConfigStr("c_fqdn"));
1425                 }
1426                 u = CtdlDirectoryLookup(NULL, synthetic_email_addr, 0);
1427                 syslog(LOG_DEBUG, "user_ops: address <%s> lookup returned <%d>", synthetic_email_addr, u);
1428         }
1429
1430         CtdlSetEmailAddressesForUser(user->fullname, synthetic_email_addr);
1431         strncpy(CC->user.emailaddrs, synthetic_email_addr, sizeof(user->emailaddrs));
1432         syslog(LOG_DEBUG, "user_ops: auto-generated email address <%s> for <%s>", synthetic_email_addr, user->fullname);
1433 }
1434
1435
1436 // Determine whether the supplied email address is subscribed to the supplied room's mailing list service.
1437 int is_email_subscribed_to_list(char *email, char *room_name) {
1438         struct ctdlroom room;
1439         long roomnum;
1440         char *roomnetconfig;
1441         int found_it = 0;
1442
1443         if (CtdlGetRoom(&room, room_name)) {
1444                 return(0);                                      // room not found, so definitely not subscribed
1445         }
1446
1447         // If this room has the QR2_SMTP_PUBLIC flag set, anyone may email a post to this room, even non-subscribers.
1448         if (room.QRflags2 & QR2_SMTP_PUBLIC) {
1449                 return(1);
1450         }
1451
1452         roomnum = room.QRnumber;
1453         roomnetconfig = LoadRoomNetConfigFile(roomnum);
1454         if (roomnetconfig == NULL) {
1455                 return(0);
1456         }
1457
1458         // We're going to do a very sloppy match here and simply search for the specified email address
1459         // anywhere in the room's netconfig.  If you don't like this, fix it yourself.
1460         if (bmstrcasestr(roomnetconfig, email)) {
1461                 found_it = 1;
1462         }
1463         else {
1464                 found_it = 0;
1465         }
1466
1467         free(roomnetconfig);
1468         return(found_it);
1469 }