citadel/modules/openid/serv_openid_rp.c

   1 /*
   2  * This is an implementation of OpenID 2.0 relying party support in stateless mode.
   3  *
   4  * Copyright (c) 2007-2012 by the citadel.org team
   5  *
   6  * This program is open source software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 3 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include "sysdep.h"
  21 #include <stdlib.h>
  22 #include <unistd.h>
  23 #include <stdio.h>
  24 #include <fcntl.h>
  25 #include <signal.h>
  26 #include <pwd.h>
  27 #include <errno.h>
  28 #include <sys/types.h>
  29
  30 #if TIME_WITH_SYS_TIME
  31 # include <sys/time.h>
  32 # include <time.h>
  33 #else
  34 # if HAVE_SYS_TIME_H
  35 #  include <sys/time.h>
  36 # else
  37 #  include <time.h>
  38 # endif
  39 #endif
  40
  41 #include <sys/wait.h>
  42 #include <string.h>
  43 #include <limits.h>
  44 #include <curl/curl.h>
  45 #include <expat.h>
  46 #include "ctdl_module.h"
  47 #include "config.h"
  48 #include "citserver.h"
  49 #include "user_ops.h"
  50
  51 typedef struct _ctdl_openid {
  52         StrBuf *op_url;                 /* OpenID Provider Endpoint URL */
  53         StrBuf *claimed_id;             /* Claimed Identifier */
  54         int verified;
  55         HashList *sreg_keys;
  56 } ctdl_openid;
  57
  58 enum {
  59         openid_disco_none,
  60         openid_disco_xrds,
  61         openid_disco_html
  62 };
  63
  64
  65 void Free_ctdl_openid(ctdl_openid **FreeMe)
  66 {
  67         if (*FreeMe == NULL) {
  68                 return;
  69         }
  70         FreeStrBuf(&(*FreeMe)->op_url);
  71         FreeStrBuf(&(*FreeMe)->claimed_id);
  72         DeleteHash(&(*FreeMe)->sreg_keys);
  73         free(*FreeMe);
  74         *FreeMe = NULL;
  75 }
  76
  77
  78 /*
  79  * This cleanup function blows away the temporary memory used by this module.
  80  */
  81 void openid_cleanup_function(void) {
  82         struct CitContext *CCC = CC;    /* CachedCitContext - performance boost */
  83
  84         if (CCC->openid_data != NULL) {
  85                 syslog(LOG_DEBUG, "Clearing OpenID session state");
  86                 Free_ctdl_openid((ctdl_openid **) &CCC->openid_data);
  87         }
  88 }
  89
  90
  91 /**************************************************************************/
  92 /*                                                                        */
  93 /* Functions in this section handle Citadel internal OpenID mapping stuff */
  94 /*                                                                        */
  95 /**************************************************************************/
  96
  97
  98 /*
  99  * The structure of an openid record *key* is:
 100  *
 101  * |--------------claimed_id-------------|
 102  *     (actual length of claimed id)
 103  *
 104  *
 105  * The structure of an openid record *value* is:
 106  *
 107  * |-----user_number----|------------claimed_id---------------|
 108  *    (sizeof long)          (actual length of claimed id)
 109  *
 110  */
 111
 112
 113
 114 /*
 115  * Attach an OpenID to a Citadel account
 116  */
 117 int attach_openid(struct ctdluser *who, StrBuf *claimed_id)
 118 {
 119         struct cdbdata *cdboi;
 120         long fetched_usernum;
 121         char *data;
 122         int data_len;
 123         char buf[2048];
 124
 125         if (!who) return(1);
 126         if (StrLength(claimed_id)==0) return(1);
 127
 128         /* Check to see if this OpenID is already in the database */
 129
 130         cdboi = cdb_fetch(CDB_OPENID, ChrPtr(claimed_id), StrLength(claimed_id));
 131         if (cdboi != NULL) {
 132                 memcpy(&fetched_usernum, cdboi->ptr, sizeof(long));
 133                 cdb_free(cdboi);
 134
 135                 if (fetched_usernum == who->usernum) {
 136                         syslog(LOG_INFO, "%s already associated; no action is taken", ChrPtr(claimed_id));
 137                         return(0);
 138                 }
 139                 else {
 140                         syslog(LOG_INFO, "%s already belongs to another user", ChrPtr(claimed_id));
 141                         return(3);
 142                 }
 143         }
 144
 145         /* Not already in the database, so attach it now */
 146
 147         data_len = sizeof(long) + StrLength(claimed_id) + 1;
 148         data = malloc(data_len);
 149
 150         memcpy(data, &who->usernum, sizeof(long));
 151         memcpy(&data[sizeof(long)], ChrPtr(claimed_id), StrLength(claimed_id) + 1);
 152
 153         cdb_store(CDB_OPENID, ChrPtr(claimed_id), StrLength(claimed_id), data, data_len);
 154         free(data);
 155
 156         snprintf(buf, sizeof buf, "User <%s> (#%ld) has claimed the OpenID URL %s\n",
 157                  who->fullname, who->usernum, ChrPtr(claimed_id));
 158         CtdlAideMessage(buf, "OpenID claim");
 159         syslog(LOG_INFO, "%s", buf);
 160         return(0);
 161 }
 162
 163
 164
 165 /*
 166  * When a user is being deleted, we have to delete any OpenID associations
 167  */
 168 void openid_purge(struct ctdluser *usbuf) {
 169         struct cdbdata *cdboi;
 170         HashList *keys = NULL;
 171         HashPos *HashPos;
 172         char *deleteme = NULL;
 173         long len;
 174         void *Value;
 175         const char *Key;
 176         long usernum = 0L;
 177
 178         keys = NewHash(1, NULL);
 179         if (!keys) return;
 180
 181         cdb_rewind(CDB_OPENID);
 182         while (cdboi = cdb_next_item(CDB_OPENID), cdboi != NULL) {
 183                 if (cdboi->len > sizeof(long)) {
 184                         memcpy(&usernum, cdboi->ptr, sizeof(long));
 185                         if (usernum == usbuf->usernum) {
 186                                 deleteme = strdup(cdboi->ptr + sizeof(long)),
 187                                 Put(keys, deleteme, strlen(deleteme), deleteme, NULL);
 188                         }
 189                 }
 190                 cdb_free(cdboi);
 191         }
 192
 193         /* Go through the hash list, deleting keys we stored in it */
 194
 195         HashPos = GetNewHashPos(keys, 0);
 196         while (GetNextHashPos(keys, HashPos, &len, &Key, &Value)!=0)
 197         {
 198                 syslog(LOG_DEBUG, "Deleting associated OpenID <%s>", (char*)Value);
 199                 cdb_delete(CDB_OPENID, Value, strlen(Value));
 200                 /* note: don't free(Value) -- deleting the hash list will handle this for us */
 201         }
 202         DeleteHashPos(&HashPos);
 203         DeleteHash(&keys);
 204 }
 205
 206
 207 /*
 208  * List the OpenIDs associated with the currently logged in account
 209  */
 210 void cmd_oidl(char *argbuf) {
 211         struct cdbdata *cdboi;
 212         long usernum = 0L;
 213
 214         if (CtdlAccessCheck(ac_logged_in)) return;
 215         cdb_rewind(CDB_OPENID);
 216         cprintf("%d Associated OpenIDs:\n", LISTING_FOLLOWS);
 217
 218         while (cdboi = cdb_next_item(CDB_OPENID), cdboi != NULL) {
 219                 if (cdboi->len > sizeof(long)) {
 220                         memcpy(&usernum, cdboi->ptr, sizeof(long));
 221                         if (usernum == CC->user.usernum) {
 222                                 cprintf("%s\n", cdboi->ptr + sizeof(long));
 223                         }
 224                 }
 225                 cdb_free(cdboi);
 226         }
 227         cprintf("000\n");
 228 }
 229
 230
 231 /*
 232  * List ALL OpenIDs in the database
 233  */
 234 void cmd_oida(char *argbuf) {
 235         struct cdbdata *cdboi;
 236         long usernum;
 237         struct ctdluser usbuf;
 238
 239         if (CtdlAccessCheck(ac_aide)) return;
 240         cdb_rewind(CDB_OPENID);
 241         cprintf("%d List of all OpenIDs in the database:\n", LISTING_FOLLOWS);
 242
 243         while (cdboi = cdb_next_item(CDB_OPENID), cdboi != NULL) {
 244                 if (cdboi->len > sizeof(long)) {
 245                         memcpy(&usernum, cdboi->ptr, sizeof(long));
 246                         if (CtdlGetUserByNumber(&usbuf, usernum) != 0) {
 247                                 usbuf.fullname[0] = 0;
 248                         }
 249                         cprintf("%s|%ld|%s\n",
 250                                 cdboi->ptr + sizeof(long),
 251                                 usernum,
 252                                 usbuf.fullname
 253                         );
 254                 }
 255                 cdb_free(cdboi);
 256         }
 257         cprintf("000\n");
 258 }
 259
 260
 261 /*
 262  * Create a new user account, manually specifying the name, after successfully
 263  * verifying an OpenID (which will of course be attached to the account)
 264  */
 265 void cmd_oidc(char *argbuf) {
 266         ctdl_openid *oiddata = (ctdl_openid *) CC->openid_data;
 267
 268         if ( (!oiddata) || (!oiddata->verified) ) {
 269                 cprintf("%d You have not verified an OpenID yet.\n", ERROR);
 270                 return;
 271         }
 272
 273         /* We can make the semantics of OIDC exactly the same as NEWU, simply
 274          * by _calling_ cmd_newu() and letting it run.  Very clever!
 275          */
 276         cmd_newu(argbuf);
 277
 278         /* Now, if this logged us in, we have to attach the OpenID */
 279         if (CC->logged_in) {
 280                 attach_openid(&CC->user, oiddata->claimed_id);
 281         }
 282
 283 }
 284
 285
 286 /*
 287  * Detach an OpenID from the currently logged in account
 288  */
 289 void cmd_oidd(char *argbuf) {
 290         struct cdbdata *cdboi;
 291         char id_to_detach[1024];
 292         int this_is_mine = 0;
 293         long usernum = 0L;
 294
 295         if (CtdlAccessCheck(ac_logged_in)) return;
 296         extract_token(id_to_detach, argbuf, 0, '|', sizeof id_to_detach);
 297         if (IsEmptyStr(id_to_detach)) {
 298                 cprintf("%d An empty OpenID URL is not allowed.\n", ERROR + ILLEGAL_VALUE);
 299         }
 300
 301         cdb_rewind(CDB_OPENID);
 302         while (cdboi = cdb_next_item(CDB_OPENID), cdboi != NULL) {
 303                 if (cdboi->len > sizeof(long)) {
 304                         memcpy(&usernum, cdboi->ptr, sizeof(long));
 305                         if (usernum == CC->user.usernum) {
 306                                 this_is_mine = 1;
 307                         }
 308                 }
 309                 cdb_free(cdboi);
 310         }
 311
 312         if (!this_is_mine) {
 313                 cprintf("%d That OpenID was not found or not associated with your account.\n",
 314                         ERROR + ILLEGAL_VALUE);
 315                 return;
 316         }
 317
 318         cdb_delete(CDB_OPENID, id_to_detach, strlen(id_to_detach));
 319         cprintf("%d %s detached from your account.\n", CIT_OK, id_to_detach);
 320 }
 321
 322
 323 /*
 324  * Attempt to auto-create a new Citadel account using the nickname from Attribute Exchange
 325  */
 326 int openid_create_user_via_ax(StrBuf *claimed_id, HashList *sreg_keys)
 327 {
 328         char *nickname = NULL;
 329         char *firstname = NULL;
 330         char *lastname = NULL;
 331         char new_password[32];
 332         long len;
 333         const char *Key;
 334         void *Value;
 335
 336         if (config.c_auth_mode != AUTHMODE_NATIVE) return(1);
 337         if (config.c_disable_newu) return(2);
 338         if (CC->logged_in) return(3);
 339
 340         HashPos *HashPos = GetNewHashPos(sreg_keys, 0);
 341         while (GetNextHashPos(sreg_keys, HashPos, &len, &Key, &Value) != 0) {
 342                 syslog(LOG_DEBUG, "%s = %s", Key, (char *)Value);
 343
 344                 if (cbmstrcasestr(Key, "value.nickname") != NULL) {
 345                         nickname = (char *)Value;
 346                 }
 347                 else if ( (nickname == NULL) && (cbmstrcasestr(Key, "value.nickname") != NULL)) {
 348                         nickname = (char *)Value;
 349                 }
 350                 else if (cbmstrcasestr(Key, "value.firstname") != NULL) {
 351                         firstname = (char *)Value;
 352                 }
 353                 else if (cbmstrcasestr(Key, "value.lastname") != NULL) {
 354                         lastname = (char *)Value;
 355                 }
 356
 357         }
 358         DeleteHashPos(&HashPos);
 359
 360         if (nickname == NULL) {
 361                 if ((firstname != NULL) || (lastname != NULL)) {
 362                         char fullname[1024] = "";
 363                         if (firstname) strcpy(fullname, firstname);
 364                         if (firstname && lastname) strcat(fullname, " ");
 365                         if (lastname) strcat(fullname, lastname);
 366                         nickname = fullname;
 367                 }
 368         }
 369
 370         if (nickname == NULL) {
 371                 return(4);
 372         }
 373         syslog(LOG_DEBUG, "The desired account name is <%s>", nickname);
 374
 375         len = cutuserkey(nickname);
 376         if (!CtdlGetUser(&CC->user, nickname)) {
 377                 syslog(LOG_DEBUG, "<%s> is already taken by another user.", nickname);
 378                 memset(&CC->user, 0, sizeof(struct ctdluser));
 379                 return(5);
 380         }
 381
 382         /* The desired account name is available.  Create the account and log it in! */
 383         if (create_user(nickname, len, 1)) return(6);
 384
 385         /* Generate a random password.
 386          * The user doesn't care what the password is since he is using OpenID.
 387          */
 388         snprintf(new_password, sizeof new_password, "%08lx%08lx", random(), random());
 389         CtdlSetPassword(new_password);
 390
 391         /* Now attach the verified OpenID to this account. */
 392         attach_openid(&CC->user, claimed_id);
 393
 394         return(0);
 395 }
 396
 397
 398 /*
 399  * If a user account exists which is associated with the Claimed ID, log it in and return zero.
 400  * Otherwise it returns nonzero.
 401  */
 402 int login_via_openid(StrBuf *claimed_id)
 403 {
 404         struct cdbdata *cdboi;
 405         long usernum = 0;
 406
 407         cdboi = cdb_fetch(CDB_OPENID, ChrPtr(claimed_id), StrLength(claimed_id));
 408         if (cdboi == NULL) {
 409                 return(-1);
 410         }
 411
 412         memcpy(&usernum, cdboi->ptr, sizeof(long));
 413         cdb_free(cdboi);
 414
 415         if (!CtdlGetUserByNumber(&CC->user, usernum)) {
 416                 /* Now become the user we just created */
 417                 safestrncpy(CC->curr_user, CC->user.fullname, sizeof CC->curr_user);
 418                 do_login();
 419                 return(0);
 420         }
 421         else {
 422                 memset(&CC->user, 0, sizeof(struct ctdluser));
 423                 return(-1);
 424         }
 425 }
 426
 427
 428
 429
 430 /**************************************************************************/
 431 /*                                                                        */
 432 /* Functions in this section handle OpenID protocol                       */
 433 /*                                                                        */
 434 /**************************************************************************/
 435
 436
 437 /*
 438  * Locate a <link> tag and, given its 'rel=' parameter, return its 'href' parameter
 439  */
 440 void extract_link(StrBuf *target_buf, const char *rel, long repllen, StrBuf *source_buf)
 441 {
 442         int i;
 443         const char *ptr;
 444         const char *href_start = NULL;
 445         const char *href_end = NULL;
 446         const char *link_tag_start = NULL;
 447         const char *link_tag_end = NULL;
 448         const char *rel_start = NULL;
 449         const char *rel_end = NULL;
 450
 451         if (!target_buf) return;
 452         if (!rel) return;
 453         if (!source_buf) return;
 454
 455         ptr = ChrPtr(source_buf);
 456
 457         FlushStrBuf(target_buf);
 458         while (ptr = cbmstrcasestr(ptr, "<link"), ptr != NULL) {
 459
 460                 link_tag_start = ptr;
 461                 link_tag_end = strchr(ptr, '>');
 462                 if (link_tag_end == NULL)
 463                         break;
 464                 for (i=0; i < 1; i++ ){
 465                         rel_start = cbmstrcasestr(link_tag_start, "rel=");
 466                         if ((rel_start == NULL) ||
 467                             (rel_start > link_tag_end))
 468                                 continue;
 469
 470                         rel_start = strchr(rel_start, '\"');
 471                         if ((rel_start == NULL) ||
 472                             (rel_start > link_tag_end))
 473                                 continue;
 474                         ++rel_start;
 475                         rel_end = strchr(rel_start, '\"');
 476                         if ((rel_end == NULL) ||
 477                             (rel_end == rel_start) ||
 478                             (rel_end >= link_tag_end) )
 479                                 continue;
 480                         if (strncasecmp(rel, rel_start, repllen)!= 0)
 481                                 continue; /* didn't match? never mind... */
 482
 483                         href_start = cbmstrcasestr(link_tag_start, "href=");
 484                         if ((href_start == NULL) ||
 485                             (href_start >= link_tag_end))
 486                                 continue;
 487                         href_start = strchr(href_start, '\"');
 488                         if ((href_start == NULL) |
 489                             (href_start >= link_tag_end))
 490                                 continue;
 491                         ++href_start;
 492                         href_end = strchr(href_start, '\"');
 493                         if ((href_end == NULL) ||
 494                             (href_end == href_start) ||
 495                             (href_start >= link_tag_end))
 496                                 continue;
 497                         StrBufPlain(target_buf, href_start, href_end - href_start);
 498                 }
 499                 ptr = link_tag_end;
 500         }
 501 }
 502
 503
 504 /*
 505  * Wrapper for curl_easy_init() that includes the options common to all calls
 506  * used in this module.
 507  */
 508 CURL *ctdl_openid_curl_easy_init(char *errmsg) {
 509         CURL *curl;
 510
 511         curl = curl_easy_init();
 512         if (!curl) {
 513                 return(curl);
 514         }
 515
 516         curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0);
 517         curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0);
 518
 519         if (errmsg) {
 520                 curl_easy_setopt(curl, CURLOPT_ERRORBUFFER, errmsg);
 521         }
 522         curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1);
 523 #ifdef CURLOPT_HTTP_CONTENT_DECODING
 524         curl_easy_setopt(curl, CURLOPT_HTTP_CONTENT_DECODING, 1);
 525         curl_easy_setopt(curl, CURLOPT_ENCODING, "");
 526 #endif
 527         curl_easy_setopt(curl, CURLOPT_USERAGENT, CITADEL);
 528         curl_easy_setopt(curl, CURLOPT_TIMEOUT, 30);            /* die after 30 seconds */
 529
 530         if (
 531                 (!IsEmptyStr(config.c_ip_addr))
 532                 && (strcmp(config.c_ip_addr, "*"))
 533                 && (strcmp(config.c_ip_addr, "::"))
 534                 && (strcmp(config.c_ip_addr, "0.0.0.0"))
 535         ) {
 536                 curl_easy_setopt(curl, CURLOPT_INTERFACE, config.c_ip_addr);
 537         }
 538
 539         return(curl);
 540 }
 541
 542
 543 struct xrds {
 544         StrBuf *CharData;
 545         int nesting_level;
 546         int in_xrd;
 547         int current_service_priority;
 548         int selected_service_priority;
 549         StrBuf *current_service_uri;
 550         StrBuf *selected_service_uri;
 551         int current_service_is_oid2auth;
 552 };
 553
 554
 555 void xrds_xml_start(void *data, const char *supplied_el, const char **attr) {
 556         struct xrds *xrds = (struct xrds *) data;
 557         int i;
 558
 559         ++xrds->nesting_level;
 560
 561         if (!strcasecmp(supplied_el, "XRD")) {
 562                 ++xrds->in_xrd;
 563         }
 564
 565         else if (!strcasecmp(supplied_el, "service")) {
 566                 xrds->current_service_priority = 0;
 567                 xrds->current_service_is_oid2auth = 0;
 568                 for (i=0; attr[i] != NULL; i+=2) {
 569                         if (!strcasecmp(attr[i], "priority")) {
 570                                 xrds->current_service_priority = atoi(attr[i+1]);
 571                         }
 572                 }
 573         }
 574
 575         FlushStrBuf(xrds->CharData);
 576 }
 577
 578
 579 void xrds_xml_end(void *data, const char *supplied_el) {
 580         struct xrds *xrds = (struct xrds *) data;
 581
 582         --xrds->nesting_level;
 583
 584         if (!strcasecmp(supplied_el, "XRD")) {
 585                 --xrds->in_xrd;
 586         }
 587
 588         else if (!strcasecmp(supplied_el, "type")) {
 589                 if (    (xrds->in_xrd)
 590                         && (!strcasecmp(ChrPtr(xrds->CharData), "http://specs.openid.net/auth/2.0/server"))
 591                 ) {
 592                         xrds->current_service_is_oid2auth = 1;
 593                 }
 594                 if (    (xrds->in_xrd)
 595                         && (!strcasecmp(ChrPtr(xrds->CharData), "http://specs.openid.net/auth/2.0/signon"))
 596                 ) {
 597                         xrds->current_service_is_oid2auth = 1;
 598                         /* FIXME in this case, the Claimed ID should be considered immutable */
 599                 }
 600         }
 601
 602         else if (!strcasecmp(supplied_el, "uri")) {
 603                 if (xrds->in_xrd) {
 604                         FlushStrBuf(xrds->current_service_uri);
 605                         StrBufAppendBuf(xrds->current_service_uri, xrds->CharData, 0);
 606                 }
 607         }
 608
 609         else if (!strcasecmp(supplied_el, "service")) {
 610                 if (    (xrds->in_xrd)
 611                         && (xrds->current_service_priority < xrds->selected_service_priority)
 612                         && (xrds->current_service_is_oid2auth)
 613                 ) {
 614                         xrds->selected_service_priority = xrds->current_service_priority;
 615                         FlushStrBuf(xrds->selected_service_uri);
 616                         StrBufAppendBuf(xrds->selected_service_uri, xrds->current_service_uri, 0);
 617                 }
 618
 619         }
 620
 621         FlushStrBuf(xrds->CharData);
 622 }
 623
 624
 625 void xrds_xml_chardata(void *data, const XML_Char *s, int len) {
 626         struct xrds *xrds = (struct xrds *) data;
 627
 628         StrBufAppendBufPlain (xrds->CharData, s, len, 0);
 629 }
 630
 631
 632 /*
 633  * Parse an XRDS document.
 634  * If an OpenID Provider URL is discovered, op_url to that value and return nonzero.
 635  * If nothing useful happened, return 0.
 636  */
 637 int parse_xrds_document(StrBuf *ReplyBuf) {
 638         ctdl_openid *oiddata = (ctdl_openid *) CC->openid_data;
 639         struct xrds xrds;
 640         int return_value = 0;
 641
 642         memset(&xrds, 0, sizeof (struct xrds));
 643         xrds.selected_service_priority = INT_MAX;
 644         xrds.CharData = NewStrBuf();
 645         xrds.current_service_uri = NewStrBuf();
 646         xrds.selected_service_uri = NewStrBuf();
 647         XML_Parser xp = XML_ParserCreate(NULL);
 648         if (xp) {
 649                 XML_SetUserData(xp, &xrds);
 650                 XML_SetElementHandler(xp, xrds_xml_start, xrds_xml_end);
 651                 XML_SetCharacterDataHandler(xp, xrds_xml_chardata);
 652                 XML_Parse(xp, ChrPtr(ReplyBuf), StrLength(ReplyBuf), 0);
 653                 XML_Parse(xp, "", 0, 1);
 654                 XML_ParserFree(xp);
 655         }
 656         else {
 657                 syslog(LOG_ALERT, "Cannot create XML parser");
 658         }
 659
 660         if (xrds.selected_service_priority < INT_MAX) {
 661                 if (oiddata->op_url == NULL) {
 662                         oiddata->op_url = NewStrBuf();
 663                 }
 664                 FlushStrBuf(oiddata->op_url);
 665                 StrBufAppendBuf(oiddata->op_url, xrds.selected_service_uri, 0);
 666                 return_value = openid_disco_xrds;
 667         }
 668
 669         FreeStrBuf(&xrds.CharData);
 670         FreeStrBuf(&xrds.current_service_uri);
 671         FreeStrBuf(&xrds.selected_service_uri);
 672
 673         return(return_value);
 674 }
 675
 676
 677 /*
 678  * Callback function for perform_openid2_discovery()
 679  * We're interested in the X-XRDS-Location: header.
 680  */
 681 size_t yadis_headerfunction(void *ptr, size_t size, size_t nmemb, void *userdata) {
 682         char hdr[1024];
 683         StrBuf **x_xrds_location = (StrBuf **) userdata;
 684
 685         memcpy(hdr, ptr, (size*nmemb));
 686         hdr[size*nmemb] = 0;
 687
 688         if (!strncasecmp(hdr, "X-XRDS-Location:", 16)) {
 689                 *x_xrds_location = NewStrBufPlain(&hdr[16], ((size*nmemb)-16));
 690                 StrBufTrim(*x_xrds_location);
 691         }
 692
 693         return(size * nmemb);
 694 }
 695
 696
 697 /* Attempt to perform Yadis discovery as specified in Yadis 1.0 section 6.2.5.
 698  *
 699  * If Yadis fails, we then attempt HTML discovery using the same document.
 700  *
 701  * If successful, returns nonzero and calls parse_xrds_document() to act upon the received data.
 702  * If fails, returns 0 and does nothing else.
 703  */
 704 int perform_openid2_discovery(StrBuf *SuppliedURL) {
 705         ctdl_openid *oiddata = (ctdl_openid *) CC->openid_data;
 706         int docbytes = (-1);
 707         StrBuf *ReplyBuf = NULL;
 708         int return_value = 0;
 709         CURL *curl;
 710         CURLcode result;
 711         char errmsg[1024] = "";
 712         struct curl_slist *my_headers = NULL;
 713         StrBuf *x_xrds_location = NULL;
 714
 715         if (!SuppliedURL) return(0);
 716         syslog(LOG_DEBUG, "perform_openid2_discovery(%s)", ChrPtr(SuppliedURL));
 717         if (StrLength(SuppliedURL) == 0) return(0);
 718
 719         ReplyBuf = NewStrBuf();
 720         if (!ReplyBuf) return(0);
 721
 722         curl = ctdl_openid_curl_easy_init(errmsg);
 723         if (!curl) return(0);
 724
 725         curl_easy_setopt(curl, CURLOPT_URL, ChrPtr(SuppliedURL));
 726         curl_easy_setopt(curl, CURLOPT_WRITEDATA, ReplyBuf);
 727         curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, CurlFillStrBuf_callback);
 728
 729         my_headers = curl_slist_append(my_headers, "Accept:");  /* disable the default Accept: header */
 730         my_headers = curl_slist_append(my_headers, "Accept: application/xrds+xml");
 731         curl_easy_setopt(curl, CURLOPT_HTTPHEADER, my_headers);
 732
 733         curl_easy_setopt(curl, CURLOPT_WRITEHEADER, &x_xrds_location);
 734         curl_easy_setopt(curl, CURLOPT_HEADERFUNCTION, yadis_headerfunction);
 735
 736         result = curl_easy_perform(curl);
 737         if (result) {
 738                 syslog(LOG_DEBUG, "libcurl error %d: %s", result, errmsg);
 739         }
 740         curl_slist_free_all(my_headers);
 741         curl_easy_cleanup(curl);
 742         docbytes = StrLength(ReplyBuf);
 743
 744         /*
 745          * The response from the server will be one of:
 746          *
 747          * Option 1: An HTML document with a <head> element that includes a <meta> element with http-equiv
 748          * attribute, X-XRDS-Location,
 749          *
 750          * Does any provider actually do this?  If so then we will implement it in the future.
 751          */
 752
 753         /*
 754          * Option 2: HTTP response-headers that include an X-XRDS-Location response-header,
 755          *           together with a document.
 756          * Option 3: HTTP response-headers only, which MAY include an X-XRDS-Location response-header,
 757          *           a contenttype response-header specifying MIME media type,
 758          *           application/xrds+xml, or both.
 759          *
 760          * If the X-XRDS-Location header was delivered, we know about it at this point...
 761          */
 762         if (    (x_xrds_location)
 763                 && (strcmp(ChrPtr(x_xrds_location), ChrPtr(SuppliedURL)))
 764         ) {
 765                 syslog(LOG_DEBUG, "X-XRDS-Location: %s ... recursing!", ChrPtr(x_xrds_location));
 766                 return_value = perform_openid2_discovery(x_xrds_location);
 767                 FreeStrBuf(&x_xrds_location);
 768         }
 769
 770         /*
 771          * Option 4: the returned web page may *be* an XRDS document.  Try to parse it.
 772          */
 773         if ( (return_value == 0) && (docbytes >= 0)) {
 774                 return_value = parse_xrds_document(ReplyBuf);
 775         }
 776
 777         /*
 778          * Option 5: if all else fails, attempt HTML based discovery.
 779          */
 780         if ( (return_value == 0) && (docbytes >= 0)) {
 781                 if (oiddata->op_url == NULL) {
 782                         oiddata->op_url = NewStrBuf();
 783                 }
 784                 extract_link(oiddata->op_url, HKEY("openid2.provider"), ReplyBuf);
 785                 if (StrLength(oiddata->op_url) > 0) {
 786                         return_value = openid_disco_html;
 787                 }
 788         }
 789
 790         if (ReplyBuf != NULL) {
 791                 FreeStrBuf(&ReplyBuf);
 792         }
 793         return(return_value);
 794 }
 795
 796
 797 /*
 798  * Setup an OpenID authentication
 799  */
 800 void cmd_oids(char *argbuf) {
 801         struct CitContext *CCC = CC;    /* CachedCitContext - performance boost */
 802         const char *Pos = NULL;
 803         StrBuf *ArgBuf = NULL;
 804         StrBuf *ReplyBuf = NULL;
 805         StrBuf *return_to = NULL;
 806         StrBuf *RedirectUrl = NULL;
 807         ctdl_openid *oiddata;
 808         int discovery_succeeded = 0;
 809
 810         Free_ctdl_openid ((ctdl_openid**)&CCC->openid_data);
 811
 812         CCC->openid_data = oiddata = malloc(sizeof(ctdl_openid));
 813         if (oiddata == NULL) {
 814                 syslog(LOG_ALERT, "malloc() failed: %s", strerror(errno));
 815                 cprintf("%d malloc failed\n", ERROR + INTERNAL_ERROR);
 816                 return;
 817         }
 818         memset(oiddata, 0, sizeof(ctdl_openid));
 819
 820         ArgBuf = NewStrBufPlain(argbuf, -1);
 821
 822         oiddata->verified = 0;
 823         oiddata->claimed_id = NewStrBufPlain(NULL, StrLength(ArgBuf));
 824         return_to = NewStrBufPlain(NULL, StrLength(ArgBuf));
 825
 826         StrBufExtract_NextToken(oiddata->claimed_id, ArgBuf, &Pos, '|');
 827         StrBufExtract_NextToken(return_to, ArgBuf, &Pos, '|');
 828
 829         syslog(LOG_DEBUG, "User-Supplied Identifier is: %s", ChrPtr(oiddata->claimed_id));
 830
 831         /********** OpenID 2.0 section 7.3 - Discovery **********/
 832
 833         /* Section 7.3.1 says we have to attempt XRI based discovery.
 834          * No one is using this, no one is asking for it, no one wants it.
 835          * So we're not even going to bother attempting this mode.
 836          */
 837
 838         /* Attempt section 7.3.2 (Yadis discovery) and section 7.3.3 (HTML discovery);
 839          */
 840         discovery_succeeded = perform_openid2_discovery(oiddata->claimed_id);
 841
 842         if (discovery_succeeded == 0) {
 843                 cprintf("%d There is no OpenID identity provider at this location.\n", ERROR);
 844         }
 845
 846         else {
 847                 /*
 848                  * If we get to this point we are in possession of a valid OpenID Provider URL.
 849                  */
 850                 syslog(LOG_DEBUG, "OP URI '%s' discovered using method %d",
 851                         ChrPtr(oiddata->op_url),
 852                         discovery_succeeded
 853                 );
 854
 855                 /* We have to "normalize" our Claimed ID otherwise it will cause some OP's to barf */
 856                 if (cbmstrcasestr(ChrPtr(oiddata->claimed_id), "://") == NULL) {
 857                         StrBuf *cid = oiddata->claimed_id;
 858                         oiddata->claimed_id = NewStrBufPlain(HKEY("http://"));
 859                         StrBufAppendBuf(oiddata->claimed_id, cid, 0);
 860                         FreeStrBuf(&cid);
 861                 }
 862
 863                 /*
 864                  * OpenID 2.0 section 9: request authentication
 865                  * Assemble a URL to which the user-agent will be redirected.
 866                  */
 867
 868                 RedirectUrl = NewStrBufDup(oiddata->op_url);
 869
 870                 StrBufAppendBufPlain(RedirectUrl, HKEY("?openid.ns="), 0);
 871                 StrBufUrlescAppend(RedirectUrl, NULL, "http://specs.openid.net/auth/2.0");
 872
 873                 StrBufAppendBufPlain(RedirectUrl, HKEY("&openid.mode=checkid_setup"), 0);
 874
 875                 StrBufAppendBufPlain(RedirectUrl, HKEY("&openid.claimed_id="), 0);
 876                 StrBufUrlescAppend(RedirectUrl, oiddata->claimed_id, NULL);
 877
 878                 StrBufAppendBufPlain(RedirectUrl, HKEY("&openid.identity="), 0);
 879                 StrBufUrlescAppend(RedirectUrl, oiddata->claimed_id, NULL);
 880
 881                 /* return_to tells the provider how to complete the round trip back to our site */
 882                 StrBufAppendBufPlain(RedirectUrl, HKEY("&openid.return_to="), 0);
 883                 StrBufUrlescAppend(RedirectUrl, return_to, NULL);
 884
 885                 /* Attribute Exchange
 886                  * See:
 887                  *      http://openid.net/specs/openid-attribute-exchange-1_0.html
 888                  *      http://code.google.com/apis/accounts/docs/OpenID.html#endpoint
 889                  *      http://test-id.net/OP/AXFetch.aspx
 890                  */
 891
 892                 StrBufAppendBufPlain(RedirectUrl, HKEY("&openid.ns.ax="), 0);
 893                 StrBufUrlescAppend(RedirectUrl, NULL, "http://openid.net/srv/ax/1.0");
 894
 895                 StrBufAppendBufPlain(RedirectUrl, HKEY("&openid.ax.mode=fetch_request"), 0);
 896
 897                 StrBufAppendBufPlain(RedirectUrl, HKEY("&openid.ax.required=firstname,lastname,friendly,nickname"), 0);
 898
 899                 StrBufAppendBufPlain(RedirectUrl, HKEY("&openid.ax.type.firstname="), 0);
 900                 StrBufUrlescAppend(RedirectUrl, NULL, "http://axschema.org/namePerson/first");
 901
 902                 StrBufAppendBufPlain(RedirectUrl, HKEY("&openid.ax.type.lastname="), 0);
 903                 StrBufUrlescAppend(RedirectUrl, NULL, "http://axschema.org/namePerson/last");
 904
 905                 StrBufAppendBufPlain(RedirectUrl, HKEY("&openid.ax.type.friendly="), 0);
 906                 StrBufUrlescAppend(RedirectUrl, NULL, "http://axschema.org/namePerson/friendly");
 907
 908                 StrBufAppendBufPlain(RedirectUrl, HKEY("&openid.ax.type.nickname="), 0);
 909                 StrBufUrlescAppend(RedirectUrl, NULL, "http://axschema.org/namePerson/nickname");
 910
 911                 syslog(LOG_DEBUG, "OpenID: redirecting client to %s", ChrPtr(RedirectUrl));
 912                 cprintf("%d %s\n", CIT_OK, ChrPtr(RedirectUrl));
 913         }
 914
 915         FreeStrBuf(&ArgBuf);
 916         FreeStrBuf(&ReplyBuf);
 917         FreeStrBuf(&return_to);
 918         FreeStrBuf(&RedirectUrl);
 919 }
 920
 921
 922 /*
 923  * Finalize an OpenID authentication
 924  */
 925 void cmd_oidf(char *argbuf) {
 926         long len;
 927         char buf[2048];
 928         char thiskey[1024];
 929         char thisdata[1024];
 930         HashList *keys = NULL;
 931         const char *Key;
 932         void *Value;
 933         ctdl_openid *oiddata = (ctdl_openid *) CC->openid_data;
 934
 935         if (oiddata == NULL) {
 936                 cprintf("%d run OIDS first.\n", ERROR + INTERNAL_ERROR);
 937                 return;
 938         }
 939         if (StrLength(oiddata->op_url) == 0){
 940                 cprintf("%d No OpenID Endpoint URL has been obtained.\n", ERROR + ILLEGAL_VALUE);
 941                 return;
 942         }
 943         keys = NewHash(1, NULL);
 944         if (!keys) {
 945                 cprintf("%d NewHash() failed\n", ERROR + INTERNAL_ERROR);
 946                 return;
 947         }
 948         cprintf("%d Transmit OpenID data now\n", START_CHAT_MODE);
 949
 950         while (client_getln(buf, sizeof buf), strcmp(buf, "000")) {
 951                 len = extract_token(thiskey, buf, 0, '|', sizeof thiskey);
 952                 if (len < 0) {
 953                         len = sizeof(thiskey) - 1;
 954                 }
 955                 extract_token(thisdata, buf, 1, '|', sizeof thisdata);
 956                 Put(keys, thiskey, len, strdup(thisdata), NULL);
 957         }
 958
 959         /* Check to see if this is a correct response.
 960          * Start with verified=1 but then set it to 0 if anything looks wrong.
 961          */
 962         oiddata->verified = 1;
 963
 964         char *openid_ns = NULL;
 965         if (    (!GetHash(keys, "ns", 2, (void *) &openid_ns))
 966                 || (strcasecmp(openid_ns, "http://specs.openid.net/auth/2.0"))
 967         ) {
 968                 syslog(LOG_DEBUG, "This is not an an OpenID assertion");
 969                 oiddata->verified = 0;
 970         }
 971
 972         char *openid_mode = NULL;
 973         if (    (!GetHash(keys, "mode", 4, (void *) &openid_mode))
 974                 || (strcasecmp(openid_mode, "id_res"))
 975         ) {
 976                 oiddata->verified = 0;
 977         }
 978
 979         char *openid_claimed_id = NULL;
 980         if (GetHash(keys, "claimed_id", 10, (void *) &openid_claimed_id)) {
 981                 FreeStrBuf(&oiddata->claimed_id);
 982                 oiddata->claimed_id = NewStrBufPlain(openid_claimed_id, -1);
 983                 syslog(LOG_DEBUG, "Provider is asserting the Claimed ID '%s'", ChrPtr(oiddata->claimed_id));
 984         }
 985
 986         /* Validate the assertion against the server */
 987         syslog(LOG_DEBUG, "Validating...");
 988
 989         CURL *curl;
 990         CURLcode res;
 991         struct curl_httppost *formpost = NULL;
 992         struct curl_httppost *lastptr = NULL;
 993         char errmsg[1024] = "";
 994         StrBuf *ReplyBuf = NewStrBuf();
 995
 996         curl_formadd(&formpost, &lastptr,
 997                 CURLFORM_COPYNAME,      "openid.mode",
 998                 CURLFORM_COPYCONTENTS,  "check_authentication",
 999                 CURLFORM_END
1000         );
1001
1002         HashPos *HashPos = GetNewHashPos(keys, 0);
1003         while (GetNextHashPos(keys, HashPos, &len, &Key, &Value) != 0) {
1004                 if (strcasecmp(Key, "mode")) {
1005                         char k_o_keyname[1024];
1006                         snprintf(k_o_keyname, sizeof k_o_keyname, "openid.%s", (const char *)Key);
1007                         curl_formadd(&formpost, &lastptr,
1008                                 CURLFORM_COPYNAME,      k_o_keyname,
1009                                 CURLFORM_COPYCONTENTS,  (char *)Value,
1010                                 CURLFORM_END
1011                         );
1012                 }
1013         }
1014         DeleteHashPos(&HashPos);
1015
1016         curl = ctdl_openid_curl_easy_init(errmsg);
1017         curl_easy_setopt(curl, CURLOPT_URL, ChrPtr(oiddata->op_url));
1018         curl_easy_setopt(curl, CURLOPT_WRITEDATA, ReplyBuf);
1019         curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, CurlFillStrBuf_callback);
1020         curl_easy_setopt(curl, CURLOPT_HTTPPOST, formpost);
1021
1022         res = curl_easy_perform(curl);
1023         if (res) {
1024                 syslog(LOG_DEBUG, "cmd_oidf() libcurl error %d: %s", res, errmsg);
1025                 oiddata->verified = 0;
1026         }
1027         curl_easy_cleanup(curl);
1028         curl_formfree(formpost);
1029
1030         /* syslog(LOG_DEBUG, "Validation reply: \n%s", ChrPtr(ReplyBuf)); */
1031         if (cbmstrcasestr(ChrPtr(ReplyBuf), "is_valid:true") == NULL) {
1032                 oiddata->verified = 0;
1033         }
1034         FreeStrBuf(&ReplyBuf);
1035
1036         syslog(LOG_DEBUG, "OpenID authentication %s", (oiddata->verified ? "succeeded" : "failed") );
1037
1038         /* Respond to the client */
1039
1040         if (oiddata->verified) {
1041
1042                 /* If we were already logged in, attach the OpenID to the user's account */
1043                 if (CC->logged_in) {
1044                         if (attach_openid(&CC->user, oiddata->claimed_id) == 0) {
1045                                 cprintf("attach\n");
1046                                 syslog(LOG_DEBUG, "OpenID attach succeeded");
1047                         }
1048                         else {
1049                                 cprintf("fail\n");
1050                                 syslog(LOG_DEBUG, "OpenID attach failed");
1051                         }
1052                 }
1053
1054                 /* Otherwise, a user is attempting to log in using the verified OpenID */
1055                 else {
1056                         /*
1057                          * Existing user who has claimed this OpenID?
1058                          *
1059                          * Note: if you think that sending the password back over the wire is insecure,
1060                          * check your assumptions.  If someone has successfully asserted an OpenID that
1061                          * is associated with the account, they already have password equivalency and can
1062                          * login, so they could just as easily change the password, etc.
1063                          */
1064                         if (login_via_openid(oiddata->claimed_id) == 0) {
1065                                 cprintf("authenticate\n%s\n%s\n", CC->user.fullname, CC->user.password);
1066                                 logged_in_response();
1067                                 syslog(LOG_DEBUG, "Logged in using previously claimed OpenID");
1068                         }
1069
1070                         /*
1071                          * If this system does not allow self-service new user registration, the
1072                          * remaining modes do not apply, so fail here and now.
1073                          */
1074                         else if (config.c_disable_newu) {
1075                                 cprintf("fail\n");
1076                                 syslog(LOG_DEBUG, "Creating user failed due to local policy");
1077                         }
1078
1079                         /*
1080                          * New user whose OpenID is verified and Attribute Exchange gave us a name?
1081                          */
1082                         else if (openid_create_user_via_ax(oiddata->claimed_id, keys) == 0) {
1083                                 cprintf("authenticate\n%s\n%s\n", CC->user.fullname, CC->user.password);
1084                                 logged_in_response();
1085                                 syslog(LOG_DEBUG, "Successfully auto-created new user");
1086                         }
1087
1088                         /*
1089                          * OpenID is verified, but the desired username either was not specified or
1090                          * conflicts with an existing user.  Manual account creation is required.
1091                          */
1092                         else {
1093                                 char *desired_name = NULL;
1094                                 cprintf("verify_only\n");
1095                                 cprintf("%s\n", ChrPtr(oiddata->claimed_id));
1096                                 if (GetHash(keys, "sreg.nickname", 13, (void *) &desired_name)) {
1097                                         cprintf("%s\n", desired_name);
1098                                 }
1099                                 else {
1100                                         cprintf("\n");
1101                                 }
1102                                 syslog(LOG_DEBUG, "The desired display name is already taken.");
1103                         }
1104                 }
1105         }
1106         else {
1107                 cprintf("fail\n");
1108         }
1109         cprintf("000\n");
1110
1111         if (oiddata->sreg_keys != NULL) {
1112                 DeleteHash(&oiddata->sreg_keys);
1113                 oiddata->sreg_keys = NULL;
1114         }
1115         oiddata->sreg_keys = keys;
1116 }
1117
1118
1119
1120 /**************************************************************************/
1121 /*                                                                        */
1122 /* Functions in this section handle module initialization and shutdown    */
1123 /*                                                                        */
1124 /**************************************************************************/
1125
1126
1127
1128
1129 CTDL_MODULE_INIT(openid_rp)
1130 {
1131         if (!threading) {
1132 // evcurl call this for us. curl_global_init(CURL_GLOBAL_ALL);
1133
1134                 /* Only enable the OpenID command set when native mode authentication is in use. */
1135                 if (config.c_auth_mode == AUTHMODE_NATIVE) {
1136                         CtdlRegisterProtoHook(cmd_oids, "OIDS", "Setup OpenID authentication");
1137                         CtdlRegisterProtoHook(cmd_oidf, "OIDF", "Finalize OpenID authentication");
1138                         CtdlRegisterProtoHook(cmd_oidl, "OIDL", "List OpenIDs associated with an account");
1139                         CtdlRegisterProtoHook(cmd_oidd, "OIDD", "Detach an OpenID from an account");
1140                         CtdlRegisterProtoHook(cmd_oidc, "OIDC", "Create new user after validating OpenID");
1141                         CtdlRegisterProtoHook(cmd_oida, "OIDA", "List all OpenIDs in the database");
1142                 }
1143                 CtdlRegisterSessionHook(openid_cleanup_function, EVT_LOGOUT, PRIO_LOGOUT + 10);
1144                 CtdlRegisterUserHook(openid_purge, EVT_PURGEUSER);
1145                 openid_level_supported = 1;     /* This module supports OpenID 1.0 only */
1146         }
1147
1148         /* return our module name for the log */
1149         return "openid_rp";
1150 }