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 (config.c_disable_newu)
 215         {
 216                 cprintf("%d this system does not support openid.\n",
 217                         ERROR + CMD_NOT_SUPPORTED);
 218                 return;
 219         }
 220         if (CtdlAccessCheck(ac_logged_in)) return;
 221
 222         cdb_rewind(CDB_OPENID);
 223         cprintf("%d Associated OpenIDs:\n", LISTING_FOLLOWS);
 224
 225         while (cdboi = cdb_next_item(CDB_OPENID), cdboi != NULL) {
 226                 if (cdboi->len > sizeof(long)) {
 227                         memcpy(&usernum, cdboi->ptr, sizeof(long));
 228                         if (usernum == CC->user.usernum) {
 229                                 cprintf("%s\n", cdboi->ptr + sizeof(long));
 230                         }
 231                 }
 232                 cdb_free(cdboi);
 233         }
 234         cprintf("000\n");
 235 }
 236
 237
 238 /*
 239  * List ALL OpenIDs in the database
 240  */
 241 void cmd_oida(char *argbuf) {
 242         struct cdbdata *cdboi;
 243         long usernum;
 244         struct ctdluser usbuf;
 245
 246         if (config.c_disable_newu)
 247         {
 248                 cprintf("%d this system does not support openid.\n",
 249                         ERROR + CMD_NOT_SUPPORTED);
 250                 return;
 251         }
 252         if (CtdlAccessCheck(ac_aide)) return;
 253         cdb_rewind(CDB_OPENID);
 254         cprintf("%d List of all OpenIDs in the database:\n", LISTING_FOLLOWS);
 255
 256         while (cdboi = cdb_next_item(CDB_OPENID), cdboi != NULL) {
 257                 if (cdboi->len > sizeof(long)) {
 258                         memcpy(&usernum, cdboi->ptr, sizeof(long));
 259                         if (CtdlGetUserByNumber(&usbuf, usernum) != 0) {
 260                                 usbuf.fullname[0] = 0;
 261                         }
 262                         cprintf("%s|%ld|%s\n",
 263                                 cdboi->ptr + sizeof(long),
 264                                 usernum,
 265                                 usbuf.fullname
 266                         );
 267                 }
 268                 cdb_free(cdboi);
 269         }
 270         cprintf("000\n");
 271 }
 272
 273
 274 /*
 275  * Create a new user account, manually specifying the name, after successfully
 276  * verifying an OpenID (which will of course be attached to the account)
 277  */
 278 void cmd_oidc(char *argbuf) {
 279         ctdl_openid *oiddata = (ctdl_openid *) CC->openid_data;
 280
 281         if (config.c_disable_newu)
 282         {
 283                 cprintf("%d this system does not support openid.\n",
 284                         ERROR + CMD_NOT_SUPPORTED);
 285                 return;
 286         }
 287         if ( (!oiddata) || (!oiddata->verified) ) {
 288                 cprintf("%d You have not verified an OpenID yet.\n", ERROR);
 289                 return;
 290         }
 291
 292         /* We can make the semantics of OIDC exactly the same as NEWU, simply
 293          * by _calling_ cmd_newu() and letting it run.  Very clever!
 294          */
 295         cmd_newu(argbuf);
 296
 297         /* Now, if this logged us in, we have to attach the OpenID */
 298         if (CC->logged_in) {
 299                 attach_openid(&CC->user, oiddata->claimed_id);
 300         }
 301
 302 }
 303
 304
 305 /*
 306  * Detach an OpenID from the currently logged in account
 307  */
 308 void cmd_oidd(char *argbuf) {
 309         struct cdbdata *cdboi;
 310         char id_to_detach[1024];
 311         int this_is_mine = 0;
 312         long usernum = 0L;
 313
 314         if (config.c_disable_newu)
 315         {
 316                 cprintf("%d this system does not support openid.\n",
 317                         ERROR + CMD_NOT_SUPPORTED);
 318                 return;
 319         }
 320         if (CtdlAccessCheck(ac_logged_in)) return;
 321         extract_token(id_to_detach, argbuf, 0, '|', sizeof id_to_detach);
 322         if (IsEmptyStr(id_to_detach)) {
 323                 cprintf("%d An empty OpenID URL is not allowed.\n", ERROR + ILLEGAL_VALUE);
 324         }
 325
 326         cdb_rewind(CDB_OPENID);
 327         while (cdboi = cdb_next_item(CDB_OPENID), cdboi != NULL) {
 328                 if (cdboi->len > sizeof(long)) {
 329                         memcpy(&usernum, cdboi->ptr, sizeof(long));
 330                         if (usernum == CC->user.usernum) {
 331                                 this_is_mine = 1;
 332                         }
 333                 }
 334                 cdb_free(cdboi);
 335         }
 336
 337         if (!this_is_mine) {
 338                 cprintf("%d That OpenID was not found or not associated with your account.\n",
 339                         ERROR + ILLEGAL_VALUE);
 340                 return;
 341         }
 342
 343         cdb_delete(CDB_OPENID, id_to_detach, strlen(id_to_detach));
 344         cprintf("%d %s detached from your account.\n", CIT_OK, id_to_detach);
 345 }
 346
 347
 348 /*
 349  * Attempt to auto-create a new Citadel account using the nickname from Attribute Exchange
 350  */
 351 int openid_create_user_via_ax(StrBuf *claimed_id, HashList *sreg_keys)
 352 {
 353         char *nickname = NULL;
 354         char *firstname = NULL;
 355         char *lastname = NULL;
 356         char new_password[32];
 357         long len;
 358         const char *Key;
 359         void *Value;
 360
 361         if (config.c_auth_mode != AUTHMODE_NATIVE) return(1);
 362         if (config.c_disable_newu) return(2);
 363         if (CC->logged_in) return(3);
 364
 365         HashPos *HashPos = GetNewHashPos(sreg_keys, 0);
 366         while (GetNextHashPos(sreg_keys, HashPos, &len, &Key, &Value) != 0) {
 367                 syslog(LOG_DEBUG, "%s = %s", Key, (char *)Value);
 368
 369                 if (cbmstrcasestr(Key, "value.nickname") != NULL) {
 370                         nickname = (char *)Value;
 371                 }
 372                 else if ( (nickname == NULL) && (cbmstrcasestr(Key, "value.nickname") != NULL)) {
 373                         nickname = (char *)Value;
 374                 }
 375                 else if (cbmstrcasestr(Key, "value.firstname") != NULL) {
 376                         firstname = (char *)Value;
 377                 }
 378                 else if (cbmstrcasestr(Key, "value.lastname") != NULL) {
 379                         lastname = (char *)Value;
 380                 }
 381
 382         }
 383         DeleteHashPos(&HashPos);
 384
 385         if (nickname == NULL) {
 386                 if ((firstname != NULL) || (lastname != NULL)) {
 387                         char fullname[1024] = "";
 388                         if (firstname) strcpy(fullname, firstname);
 389                         if (firstname && lastname) strcat(fullname, " ");
 390                         if (lastname) strcat(fullname, lastname);
 391                         nickname = fullname;
 392                 }
 393         }
 394
 395         if (nickname == NULL) {
 396                 return(4);
 397         }
 398         syslog(LOG_DEBUG, "The desired account name is <%s>", nickname);
 399
 400         len = cutuserkey(nickname);
 401         if (!CtdlGetUser(&CC->user, nickname)) {
 402                 syslog(LOG_DEBUG, "<%s> is already taken by another user.", nickname);
 403                 memset(&CC->user, 0, sizeof(struct ctdluser));
 404                 return(5);
 405         }
 406
 407         /* The desired account name is available.  Create the account and log it in! */
 408         if (create_user(nickname, len, 1)) return(6);
 409
 410         /* Generate a random password.
 411          * The user doesn't care what the password is since he is using OpenID.
 412          */
 413         snprintf(new_password, sizeof new_password, "%08lx%08lx", random(), random());
 414         CtdlSetPassword(new_password);
 415
 416         /* Now attach the verified OpenID to this account. */
 417         attach_openid(&CC->user, claimed_id);
 418
 419         return(0);
 420 }
 421
 422
 423 /*
 424  * If a user account exists which is associated with the Claimed ID, log it in and return zero.
 425  * Otherwise it returns nonzero.
 426  */
 427 int login_via_openid(StrBuf *claimed_id)
 428 {
 429         struct cdbdata *cdboi;
 430         long usernum = 0;
 431
 432         cdboi = cdb_fetch(CDB_OPENID, ChrPtr(claimed_id), StrLength(claimed_id));
 433         if (cdboi == NULL) {
 434                 return(-1);
 435         }
 436
 437         memcpy(&usernum, cdboi->ptr, sizeof(long));
 438         cdb_free(cdboi);
 439
 440         if (!CtdlGetUserByNumber(&CC->user, usernum)) {
 441                 /* Now become the user we just created */
 442                 safestrncpy(CC->curr_user, CC->user.fullname, sizeof CC->curr_user);
 443                 do_login();
 444                 return(0);
 445         }
 446         else {
 447                 memset(&CC->user, 0, sizeof(struct ctdluser));
 448                 return(-1);
 449         }
 450 }
 451
 452
 453
 454
 455 /**************************************************************************/
 456 /*                                                                        */
 457 /* Functions in this section handle OpenID protocol                       */
 458 /*                                                                        */
 459 /**************************************************************************/
 460
 461
 462 /*
 463  * Locate a <link> tag and, given its 'rel=' parameter, return its 'href' parameter
 464  */
 465 void extract_link(StrBuf *target_buf, const char *rel, long repllen, StrBuf *source_buf)
 466 {
 467         int i;
 468         const char *ptr;
 469         const char *href_start = NULL;
 470         const char *href_end = NULL;
 471         const char *link_tag_start = NULL;
 472         const char *link_tag_end = NULL;
 473         const char *rel_start = NULL;
 474         const char *rel_end = NULL;
 475
 476         if (!target_buf) return;
 477         if (!rel) return;
 478         if (!source_buf) return;
 479
 480         ptr = ChrPtr(source_buf);
 481
 482         FlushStrBuf(target_buf);
 483         while (ptr = cbmstrcasestr(ptr, "<link"), ptr != NULL) {
 484
 485                 link_tag_start = ptr;
 486                 link_tag_end = strchr(ptr, '>');
 487                 if (link_tag_end == NULL)
 488                         break;
 489                 for (i=0; i < 1; i++ ){
 490                         rel_start = cbmstrcasestr(link_tag_start, "rel=");
 491                         if ((rel_start == NULL) ||
 492                             (rel_start > link_tag_end))
 493                                 continue;
 494
 495                         rel_start = strchr(rel_start, '\"');
 496                         if ((rel_start == NULL) ||
 497                             (rel_start > link_tag_end))
 498                                 continue;
 499                         ++rel_start;
 500                         rel_end = strchr(rel_start, '\"');
 501                         if ((rel_end == NULL) ||
 502                             (rel_end == rel_start) ||
 503                             (rel_end >= link_tag_end) )
 504                                 continue;
 505                         if (strncasecmp(rel, rel_start, repllen)!= 0)
 506                                 continue; /* didn't match? never mind... */
 507
 508                         href_start = cbmstrcasestr(link_tag_start, "href=");
 509                         if ((href_start == NULL) ||
 510                             (href_start >= link_tag_end))
 511                                 continue;
 512                         href_start = strchr(href_start, '\"');
 513                         if ((href_start == NULL) |
 514                             (href_start >= link_tag_end))
 515                                 continue;
 516                         ++href_start;
 517                         href_end = strchr(href_start, '\"');
 518                         if ((href_end == NULL) ||
 519                             (href_end == href_start) ||
 520                             (href_start >= link_tag_end))
 521                                 continue;
 522                         StrBufPlain(target_buf, href_start, href_end - href_start);
 523                 }
 524                 ptr = link_tag_end;
 525         }
 526 }
 527
 528
 529 /*
 530  * Wrapper for curl_easy_init() that includes the options common to all calls
 531  * used in this module.
 532  */
 533 CURL *ctdl_openid_curl_easy_init(char *errmsg) {
 534         CURL *curl;
 535
 536         curl = curl_easy_init();
 537         if (!curl) {
 538                 return(curl);
 539         }
 540
 541         curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0);
 542         curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0);
 543
 544         if (errmsg) {
 545                 curl_easy_setopt(curl, CURLOPT_ERRORBUFFER, errmsg);
 546         }
 547         curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1);
 548 #ifdef CURLOPT_HTTP_CONTENT_DECODING
 549         curl_easy_setopt(curl, CURLOPT_HTTP_CONTENT_DECODING, 1);
 550         curl_easy_setopt(curl, CURLOPT_ENCODING, "");
 551 #endif
 552         curl_easy_setopt(curl, CURLOPT_USERAGENT, CITADEL);
 553         curl_easy_setopt(curl, CURLOPT_TIMEOUT, 30);            /* die after 30 seconds */
 554
 555         if (
 556                 (!IsEmptyStr(config.c_ip_addr))
 557                 && (strcmp(config.c_ip_addr, "*"))
 558                 && (strcmp(config.c_ip_addr, "::"))
 559                 && (strcmp(config.c_ip_addr, "0.0.0.0"))
 560         ) {
 561                 curl_easy_setopt(curl, CURLOPT_INTERFACE, config.c_ip_addr);
 562         }
 563
 564         return(curl);
 565 }
 566
 567
 568 struct xrds {
 569         StrBuf *CharData;
 570         int nesting_level;
 571         int in_xrd;
 572         int current_service_priority;
 573         int selected_service_priority;
 574         StrBuf *current_service_uri;
 575         StrBuf *selected_service_uri;
 576         int current_service_is_oid2auth;
 577 };
 578
 579
 580 void xrds_xml_start(void *data, const char *supplied_el, const char **attr) {
 581         struct xrds *xrds = (struct xrds *) data;
 582         int i;
 583
 584         ++xrds->nesting_level;
 585
 586         if (!strcasecmp(supplied_el, "XRD")) {
 587                 ++xrds->in_xrd;
 588         }
 589
 590         else if (!strcasecmp(supplied_el, "service")) {
 591                 xrds->current_service_priority = 0;
 592                 xrds->current_service_is_oid2auth = 0;
 593                 for (i=0; attr[i] != NULL; i+=2) {
 594                         if (!strcasecmp(attr[i], "priority")) {
 595                                 xrds->current_service_priority = atoi(attr[i+1]);
 596                         }
 597                 }
 598         }
 599
 600         FlushStrBuf(xrds->CharData);
 601 }
 602
 603
 604 void xrds_xml_end(void *data, const char *supplied_el) {
 605         struct xrds *xrds = (struct xrds *) data;
 606
 607         --xrds->nesting_level;
 608
 609         if (!strcasecmp(supplied_el, "XRD")) {
 610                 --xrds->in_xrd;
 611         }
 612
 613         else if (!strcasecmp(supplied_el, "type")) {
 614                 if (    (xrds->in_xrd)
 615                         && (!strcasecmp(ChrPtr(xrds->CharData), "http://specs.openid.net/auth/2.0/server"))
 616                 ) {
 617                         xrds->current_service_is_oid2auth = 1;
 618                 }
 619                 if (    (xrds->in_xrd)
 620                         && (!strcasecmp(ChrPtr(xrds->CharData), "http://specs.openid.net/auth/2.0/signon"))
 621                 ) {
 622                         xrds->current_service_is_oid2auth = 1;
 623                         /* FIXME in this case, the Claimed ID should be considered immutable */
 624                 }
 625         }
 626
 627         else if (!strcasecmp(supplied_el, "uri")) {
 628                 if (xrds->in_xrd) {
 629                         FlushStrBuf(xrds->current_service_uri);
 630                         StrBufAppendBuf(xrds->current_service_uri, xrds->CharData, 0);
 631                 }
 632         }
 633
 634         else if (!strcasecmp(supplied_el, "service")) {
 635                 if (    (xrds->in_xrd)
 636                         && (xrds->current_service_priority < xrds->selected_service_priority)
 637                         && (xrds->current_service_is_oid2auth)
 638                 ) {
 639                         xrds->selected_service_priority = xrds->current_service_priority;
 640                         FlushStrBuf(xrds->selected_service_uri);
 641                         StrBufAppendBuf(xrds->selected_service_uri, xrds->current_service_uri, 0);
 642                 }
 643
 644         }
 645
 646         FlushStrBuf(xrds->CharData);
 647 }
 648
 649
 650 void xrds_xml_chardata(void *data, const XML_Char *s, int len) {
 651         struct xrds *xrds = (struct xrds *) data;
 652
 653         StrBufAppendBufPlain (xrds->CharData, s, len, 0);
 654 }
 655
 656
 657 /*
 658  * Parse an XRDS document.
 659  * If an OpenID Provider URL is discovered, op_url to that value and return nonzero.
 660  * If nothing useful happened, return 0.
 661  */
 662 int parse_xrds_document(StrBuf *ReplyBuf) {
 663         ctdl_openid *oiddata = (ctdl_openid *) CC->openid_data;
 664         struct xrds xrds;
 665         int return_value = 0;
 666
 667         memset(&xrds, 0, sizeof (struct xrds));
 668         xrds.selected_service_priority = INT_MAX;
 669         xrds.CharData = NewStrBuf();
 670         xrds.current_service_uri = NewStrBuf();
 671         xrds.selected_service_uri = NewStrBuf();
 672         XML_Parser xp = XML_ParserCreate(NULL);
 673         if (xp) {
 674                 XML_SetUserData(xp, &xrds);
 675                 XML_SetElementHandler(xp, xrds_xml_start, xrds_xml_end);
 676                 XML_SetCharacterDataHandler(xp, xrds_xml_chardata);
 677                 XML_Parse(xp, ChrPtr(ReplyBuf), StrLength(ReplyBuf), 0);
 678                 XML_Parse(xp, "", 0, 1);
 679                 XML_ParserFree(xp);
 680         }
 681         else {
 682                 syslog(LOG_ALERT, "Cannot create XML parser");
 683         }
 684
 685         if (xrds.selected_service_priority < INT_MAX) {
 686                 if (oiddata->op_url == NULL) {
 687                         oiddata->op_url = NewStrBuf();
 688                 }
 689                 FlushStrBuf(oiddata->op_url);
 690                 StrBufAppendBuf(oiddata->op_url, xrds.selected_service_uri, 0);
 691                 return_value = openid_disco_xrds;
 692         }
 693
 694         FreeStrBuf(&xrds.CharData);
 695         FreeStrBuf(&xrds.current_service_uri);
 696         FreeStrBuf(&xrds.selected_service_uri);
 697
 698         return(return_value);
 699 }
 700
 701
 702 /*
 703  * Callback function for perform_openid2_discovery()
 704  * We're interested in the X-XRDS-Location: header.
 705  */
 706 size_t yadis_headerfunction(void *ptr, size_t size, size_t nmemb, void *userdata) {
 707         char hdr[1024];
 708         StrBuf **x_xrds_location = (StrBuf **) userdata;
 709
 710         memcpy(hdr, ptr, (size*nmemb));
 711         hdr[size*nmemb] = 0;
 712
 713         if (!strncasecmp(hdr, "X-XRDS-Location:", 16)) {
 714                 *x_xrds_location = NewStrBufPlain(&hdr[16], ((size*nmemb)-16));
 715                 StrBufTrim(*x_xrds_location);
 716         }
 717
 718         return(size * nmemb);
 719 }
 720
 721
 722 /* Attempt to perform Yadis discovery as specified in Yadis 1.0 section 6.2.5.
 723  *
 724  * If Yadis fails, we then attempt HTML discovery using the same document.
 725  *
 726  * If successful, returns nonzero and calls parse_xrds_document() to act upon the received data.
 727  * If fails, returns 0 and does nothing else.
 728  */
 729 int perform_openid2_discovery(StrBuf *SuppliedURL) {
 730         ctdl_openid *oiddata = (ctdl_openid *) CC->openid_data;
 731         int docbytes = (-1);
 732         StrBuf *ReplyBuf = NULL;
 733         int return_value = 0;
 734         CURL *curl;
 735         CURLcode result;
 736         char errmsg[1024] = "";
 737         struct curl_slist *my_headers = NULL;
 738         StrBuf *x_xrds_location = NULL;
 739
 740         if (!SuppliedURL) return(0);
 741         syslog(LOG_DEBUG, "perform_openid2_discovery(%s)", ChrPtr(SuppliedURL));
 742         if (StrLength(SuppliedURL) == 0) return(0);
 743
 744         ReplyBuf = NewStrBuf();
 745         if (!ReplyBuf) return(0);
 746
 747         curl = ctdl_openid_curl_easy_init(errmsg);
 748         if (!curl) return(0);
 749
 750         curl_easy_setopt(curl, CURLOPT_URL, ChrPtr(SuppliedURL));
 751         curl_easy_setopt(curl, CURLOPT_WRITEDATA, ReplyBuf);
 752         curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, CurlFillStrBuf_callback);
 753
 754         my_headers = curl_slist_append(my_headers, "Accept:");  /* disable the default Accept: header */
 755         my_headers = curl_slist_append(my_headers, "Accept: application/xrds+xml");
 756         curl_easy_setopt(curl, CURLOPT_HTTPHEADER, my_headers);
 757
 758         curl_easy_setopt(curl, CURLOPT_WRITEHEADER, &x_xrds_location);
 759         curl_easy_setopt(curl, CURLOPT_HEADERFUNCTION, yadis_headerfunction);
 760
 761         result = curl_easy_perform(curl);
 762         if (result) {
 763                 syslog(LOG_DEBUG, "libcurl error %d: %s", result, errmsg);
 764         }
 765         curl_slist_free_all(my_headers);
 766         curl_easy_cleanup(curl);
 767         docbytes = StrLength(ReplyBuf);
 768
 769         /*
 770          * The response from the server will be one of:
 771          *
 772          * Option 1: An HTML document with a <head> element that includes a <meta> element with http-equiv
 773          * attribute, X-XRDS-Location,
 774          *
 775          * Does any provider actually do this?  If so then we will implement it in the future.
 776          */
 777
 778         /*
 779          * Option 2: HTTP response-headers that include an X-XRDS-Location response-header,
 780          *           together with a document.
 781          * Option 3: HTTP response-headers only, which MAY include an X-XRDS-Location response-header,
 782          *           a contenttype response-header specifying MIME media type,
 783          *           application/xrds+xml, or both.
 784          *
 785          * If the X-XRDS-Location header was delivered, we know about it at this point...
 786          */
 787         if (    (x_xrds_location)
 788                 && (strcmp(ChrPtr(x_xrds_location), ChrPtr(SuppliedURL)))
 789         ) {
 790                 syslog(LOG_DEBUG, "X-XRDS-Location: %s ... recursing!", ChrPtr(x_xrds_location));
 791                 return_value = perform_openid2_discovery(x_xrds_location);
 792                 FreeStrBuf(&x_xrds_location);
 793         }
 794
 795         /*
 796          * Option 4: the returned web page may *be* an XRDS document.  Try to parse it.
 797          */
 798         if ( (return_value == 0) && (docbytes >= 0)) {
 799                 return_value = parse_xrds_document(ReplyBuf);
 800         }
 801
 802         /*
 803          * Option 5: if all else fails, attempt HTML based discovery.
 804          */
 805         if ( (return_value == 0) && (docbytes >= 0)) {
 806                 if (oiddata->op_url == NULL) {
 807                         oiddata->op_url = NewStrBuf();
 808                 }
 809                 extract_link(oiddata->op_url, HKEY("openid2.provider"), ReplyBuf);
 810                 if (StrLength(oiddata->op_url) > 0) {
 811                         return_value = openid_disco_html;
 812                 }
 813         }
 814
 815         if (ReplyBuf != NULL) {
 816                 FreeStrBuf(&ReplyBuf);
 817         }
 818         return(return_value);
 819 }
 820
 821
 822 /*
 823  * Setup an OpenID authentication
 824  */
 825 void cmd_oids(char *argbuf) {
 826         struct CitContext *CCC = CC;    /* CachedCitContext - performance boost */
 827         const char *Pos = NULL;
 828         StrBuf *ArgBuf = NULL;
 829         StrBuf *ReplyBuf = NULL;
 830         StrBuf *return_to = NULL;
 831         StrBuf *RedirectUrl = NULL;
 832         ctdl_openid *oiddata;
 833         int discovery_succeeded = 0;
 834
 835         if (config.c_disable_newu)
 836         {
 837                 cprintf("%d this system does not support openid.\n",
 838                         ERROR + CMD_NOT_SUPPORTED);
 839                 return;
 840         }
 841         Free_ctdl_openid ((ctdl_openid**)&CCC->openid_data);
 842
 843         CCC->openid_data = oiddata = malloc(sizeof(ctdl_openid));
 844         if (oiddata == NULL) {
 845                 syslog(LOG_ALERT, "malloc() failed: %s", strerror(errno));
 846                 cprintf("%d malloc failed\n", ERROR + INTERNAL_ERROR);
 847                 return;
 848         }
 849         memset(oiddata, 0, sizeof(ctdl_openid));
 850
 851         ArgBuf = NewStrBufPlain(argbuf, -1);
 852
 853         oiddata->verified = 0;
 854         oiddata->claimed_id = NewStrBufPlain(NULL, StrLength(ArgBuf));
 855         return_to = NewStrBufPlain(NULL, StrLength(ArgBuf));
 856
 857         StrBufExtract_NextToken(oiddata->claimed_id, ArgBuf, &Pos, '|');
 858         StrBufExtract_NextToken(return_to, ArgBuf, &Pos, '|');
 859
 860         syslog(LOG_DEBUG, "User-Supplied Identifier is: %s", ChrPtr(oiddata->claimed_id));
 861
 862         /********** OpenID 2.0 section 7.3 - Discovery **********/
 863
 864         /* Section 7.3.1 says we have to attempt XRI based discovery.
 865          * No one is using this, no one is asking for it, no one wants it.
 866          * So we're not even going to bother attempting this mode.
 867          */
 868
 869         /* Attempt section 7.3.2 (Yadis discovery) and section 7.3.3 (HTML discovery);
 870          */
 871         discovery_succeeded = perform_openid2_discovery(oiddata->claimed_id);
 872
 873         if (discovery_succeeded == 0) {
 874                 cprintf("%d There is no OpenID identity provider at this location.\n", ERROR);
 875         }
 876
 877         else {
 878                 /*
 879                  * If we get to this point we are in possession of a valid OpenID Provider URL.
 880                  */
 881                 syslog(LOG_DEBUG, "OP URI '%s' discovered using method %d",
 882                         ChrPtr(oiddata->op_url),
 883                         discovery_succeeded
 884                 );
 885
 886                 /* We have to "normalize" our Claimed ID otherwise it will cause some OP's to barf */
 887                 if (cbmstrcasestr(ChrPtr(oiddata->claimed_id), "://") == NULL) {
 888                         StrBuf *cid = oiddata->claimed_id;
 889                         oiddata->claimed_id = NewStrBufPlain(HKEY("http://"));
 890                         StrBufAppendBuf(oiddata->claimed_id, cid, 0);
 891                         FreeStrBuf(&cid);
 892                 }
 893
 894                 /*
 895                  * OpenID 2.0 section 9: request authentication
 896                  * Assemble a URL to which the user-agent will be redirected.
 897                  */
 898
 899                 RedirectUrl = NewStrBufDup(oiddata->op_url);
 900
 901                 StrBufAppendBufPlain(RedirectUrl, HKEY("?openid.ns="), 0);
 902                 StrBufUrlescAppend(RedirectUrl, NULL, "http://specs.openid.net/auth/2.0");
 903
 904                 StrBufAppendBufPlain(RedirectUrl, HKEY("&openid.mode=checkid_setup"), 0);
 905
 906                 StrBufAppendBufPlain(RedirectUrl, HKEY("&openid.claimed_id="), 0);
 907                 StrBufUrlescAppend(RedirectUrl, oiddata->claimed_id, NULL);
 908
 909                 StrBufAppendBufPlain(RedirectUrl, HKEY("&openid.identity="), 0);
 910                 StrBufUrlescAppend(RedirectUrl, oiddata->claimed_id, NULL);
 911
 912                 /* return_to tells the provider how to complete the round trip back to our site */
 913                 StrBufAppendBufPlain(RedirectUrl, HKEY("&openid.return_to="), 0);
 914                 StrBufUrlescAppend(RedirectUrl, return_to, NULL);
 915
 916                 /* Attribute Exchange
 917                  * See:
 918                  *      http://openid.net/specs/openid-attribute-exchange-1_0.html
 919                  *      http://code.google.com/apis/accounts/docs/OpenID.html#endpoint
 920                  *      http://test-id.net/OP/AXFetch.aspx
 921                  */
 922
 923                 StrBufAppendBufPlain(RedirectUrl, HKEY("&openid.ns.ax="), 0);
 924                 StrBufUrlescAppend(RedirectUrl, NULL, "http://openid.net/srv/ax/1.0");
 925
 926                 StrBufAppendBufPlain(RedirectUrl, HKEY("&openid.ax.mode=fetch_request"), 0);
 927
 928                 StrBufAppendBufPlain(RedirectUrl, HKEY("&openid.ax.required=firstname,lastname,friendly,nickname"), 0);
 929
 930                 StrBufAppendBufPlain(RedirectUrl, HKEY("&openid.ax.type.firstname="), 0);
 931                 StrBufUrlescAppend(RedirectUrl, NULL, "http://axschema.org/namePerson/first");
 932
 933                 StrBufAppendBufPlain(RedirectUrl, HKEY("&openid.ax.type.lastname="), 0);
 934                 StrBufUrlescAppend(RedirectUrl, NULL, "http://axschema.org/namePerson/last");
 935
 936                 StrBufAppendBufPlain(RedirectUrl, HKEY("&openid.ax.type.friendly="), 0);
 937                 StrBufUrlescAppend(RedirectUrl, NULL, "http://axschema.org/namePerson/friendly");
 938
 939                 StrBufAppendBufPlain(RedirectUrl, HKEY("&openid.ax.type.nickname="), 0);
 940                 StrBufUrlescAppend(RedirectUrl, NULL, "http://axschema.org/namePerson/nickname");
 941
 942                 syslog(LOG_DEBUG, "OpenID: redirecting client to %s", ChrPtr(RedirectUrl));
 943                 cprintf("%d %s\n", CIT_OK, ChrPtr(RedirectUrl));
 944         }
 945
 946         FreeStrBuf(&ArgBuf);
 947         FreeStrBuf(&ReplyBuf);
 948         FreeStrBuf(&return_to);
 949         FreeStrBuf(&RedirectUrl);
 950 }
 951
 952
 953 /*
 954  * Finalize an OpenID authentication
 955  */
 956 void cmd_oidf(char *argbuf) {
 957         long len;
 958         char buf[2048];
 959         char thiskey[1024];
 960         char thisdata[1024];
 961         HashList *keys = NULL;
 962         const char *Key;
 963         void *Value;
 964         ctdl_openid *oiddata = (ctdl_openid *) CC->openid_data;
 965
 966         if (config.c_disable_newu)
 967         {
 968                 cprintf("%d this system does not support openid.\n",
 969                         ERROR + CMD_NOT_SUPPORTED);
 970                 return;
 971         }
 972         if (oiddata == NULL) {
 973                 cprintf("%d run OIDS first.\n", ERROR + INTERNAL_ERROR);
 974                 return;
 975         }
 976         if (StrLength(oiddata->op_url) == 0){
 977                 cprintf("%d No OpenID Endpoint URL has been obtained.\n", ERROR + ILLEGAL_VALUE);
 978                 return;
 979         }
 980         keys = NewHash(1, NULL);
 981         if (!keys) {
 982                 cprintf("%d NewHash() failed\n", ERROR + INTERNAL_ERROR);
 983                 return;
 984         }
 985         cprintf("%d Transmit OpenID data now\n", START_CHAT_MODE);
 986
 987         while (client_getln(buf, sizeof buf), strcmp(buf, "000")) {
 988                 len = extract_token(thiskey, buf, 0, '|', sizeof thiskey);
 989                 if (len < 0) {
 990                         len = sizeof(thiskey) - 1;
 991                 }
 992                 extract_token(thisdata, buf, 1, '|', sizeof thisdata);
 993                 Put(keys, thiskey, len, strdup(thisdata), NULL);
 994         }
 995
 996         /* Check to see if this is a correct response.
 997          * Start with verified=1 but then set it to 0 if anything looks wrong.
 998          */
 999         oiddata->verified = 1;
1000
1001         char *openid_ns = NULL;
1002         if (    (!GetHash(keys, "ns", 2, (void *) &openid_ns))
1003                 || (strcasecmp(openid_ns, "http://specs.openid.net/auth/2.0"))
1004         ) {
1005                 syslog(LOG_DEBUG, "This is not an an OpenID assertion");
1006                 oiddata->verified = 0;
1007         }
1008
1009         char *openid_mode = NULL;
1010         if (    (!GetHash(keys, "mode", 4, (void *) &openid_mode))
1011                 || (strcasecmp(openid_mode, "id_res"))
1012         ) {
1013                 oiddata->verified = 0;
1014         }
1015
1016         char *openid_claimed_id = NULL;
1017         if (GetHash(keys, "claimed_id", 10, (void *) &openid_claimed_id)) {
1018                 FreeStrBuf(&oiddata->claimed_id);
1019                 oiddata->claimed_id = NewStrBufPlain(openid_claimed_id, -1);
1020                 syslog(LOG_DEBUG, "Provider is asserting the Claimed ID '%s'", ChrPtr(oiddata->claimed_id));
1021         }
1022
1023         /* Validate the assertion against the server */
1024         syslog(LOG_DEBUG, "Validating...");
1025
1026         CURL *curl;
1027         CURLcode res;
1028         struct curl_httppost *formpost = NULL;
1029         struct curl_httppost *lastptr = NULL;
1030         char errmsg[1024] = "";
1031         StrBuf *ReplyBuf = NewStrBuf();
1032
1033         curl_formadd(&formpost, &lastptr,
1034                 CURLFORM_COPYNAME,      "openid.mode",
1035                 CURLFORM_COPYCONTENTS,  "check_authentication",
1036                 CURLFORM_END
1037         );
1038
1039         HashPos *HashPos = GetNewHashPos(keys, 0);
1040         while (GetNextHashPos(keys, HashPos, &len, &Key, &Value) != 0) {
1041                 if (strcasecmp(Key, "mode")) {
1042                         char k_o_keyname[1024];
1043                         snprintf(k_o_keyname, sizeof k_o_keyname, "openid.%s", (const char *)Key);
1044                         curl_formadd(&formpost, &lastptr,
1045                                 CURLFORM_COPYNAME,      k_o_keyname,
1046                                 CURLFORM_COPYCONTENTS,  (char *)Value,
1047                                 CURLFORM_END
1048                         );
1049                 }
1050         }
1051         DeleteHashPos(&HashPos);
1052
1053         curl = ctdl_openid_curl_easy_init(errmsg);
1054         curl_easy_setopt(curl, CURLOPT_URL, ChrPtr(oiddata->op_url));
1055         curl_easy_setopt(curl, CURLOPT_WRITEDATA, ReplyBuf);
1056         curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, CurlFillStrBuf_callback);
1057         curl_easy_setopt(curl, CURLOPT_HTTPPOST, formpost);
1058
1059         res = curl_easy_perform(curl);
1060         if (res) {
1061                 syslog(LOG_DEBUG, "cmd_oidf() libcurl error %d: %s", res, errmsg);
1062                 oiddata->verified = 0;
1063         }
1064         curl_easy_cleanup(curl);
1065         curl_formfree(formpost);
1066
1067         /* syslog(LOG_DEBUG, "Validation reply: \n%s", ChrPtr(ReplyBuf)); */
1068         if (cbmstrcasestr(ChrPtr(ReplyBuf), "is_valid:true") == NULL) {
1069                 oiddata->verified = 0;
1070         }
1071         FreeStrBuf(&ReplyBuf);
1072
1073         syslog(LOG_DEBUG, "OpenID authentication %s", (oiddata->verified ? "succeeded" : "failed") );
1074
1075         /* Respond to the client */
1076
1077         if (oiddata->verified) {
1078
1079                 /* If we were already logged in, attach the OpenID to the user's account */
1080                 if (CC->logged_in) {
1081                         if (attach_openid(&CC->user, oiddata->claimed_id) == 0) {
1082                                 cprintf("attach\n");
1083                                 syslog(LOG_DEBUG, "OpenID attach succeeded");
1084                         }
1085                         else {
1086                                 cprintf("fail\n");
1087                                 syslog(LOG_DEBUG, "OpenID attach failed");
1088                         }
1089                 }
1090
1091                 /* Otherwise, a user is attempting to log in using the verified OpenID */
1092                 else {
1093                         /*
1094                          * Existing user who has claimed this OpenID?
1095                          *
1096                          * Note: if you think that sending the password back over the wire is insecure,
1097                          * check your assumptions.  If someone has successfully asserted an OpenID that
1098                          * is associated with the account, they already have password equivalency and can
1099                          * login, so they could just as easily change the password, etc.
1100                          */
1101                         if (login_via_openid(oiddata->claimed_id) == 0) {
1102                                 cprintf("authenticate\n%s\n%s\n", CC->user.fullname, CC->user.password);
1103                                 logged_in_response();
1104                                 syslog(LOG_DEBUG, "Logged in using previously claimed OpenID");
1105                         }
1106
1107                         /*
1108                          * If this system does not allow self-service new user registration, the
1109                          * remaining modes do not apply, so fail here and now.
1110                          */
1111                         else if (config.c_disable_newu) {
1112                                 cprintf("fail\n");
1113                                 syslog(LOG_DEBUG, "Creating user failed due to local policy");
1114                         }
1115
1116                         /*
1117                          * New user whose OpenID is verified and Attribute Exchange gave us a name?
1118                          */
1119                         else if (openid_create_user_via_ax(oiddata->claimed_id, keys) == 0) {
1120                                 cprintf("authenticate\n%s\n%s\n", CC->user.fullname, CC->user.password);
1121                                 logged_in_response();
1122                                 syslog(LOG_DEBUG, "Successfully auto-created new user");
1123                         }
1124
1125                         /*
1126                          * OpenID is verified, but the desired username either was not specified or
1127                          * conflicts with an existing user.  Manual account creation is required.
1128                          */
1129                         else {
1130                                 char *desired_name = NULL;
1131                                 cprintf("verify_only\n");
1132                                 cprintf("%s\n", ChrPtr(oiddata->claimed_id));
1133                                 if (GetHash(keys, "sreg.nickname", 13, (void *) &desired_name)) {
1134                                         cprintf("%s\n", desired_name);
1135                                 }
1136                                 else {
1137                                         cprintf("\n");
1138                                 }
1139                                 syslog(LOG_DEBUG, "The desired display name is already taken.");
1140                         }
1141                 }
1142         }
1143         else {
1144                 cprintf("fail\n");
1145         }
1146         cprintf("000\n");
1147
1148         if (oiddata->sreg_keys != NULL) {
1149                 DeleteHash(&oiddata->sreg_keys);
1150                 oiddata->sreg_keys = NULL;
1151         }
1152         oiddata->sreg_keys = keys;
1153 }
1154
1155
1156
1157 /**************************************************************************/
1158 /*                                                                        */
1159 /* Functions in this section handle module initialization and shutdown    */
1160 /*                                                                        */
1161 /**************************************************************************/
1162
1163
1164
1165
1166 CTDL_MODULE_INIT(openid_rp)
1167 {
1168         if (!threading) {
1169 // evcurl call this for us. curl_global_init(CURL_GLOBAL_ALL);
1170
1171                 /* Only enable the OpenID command set when native mode authentication is in use. */
1172                 if (config.c_auth_mode == AUTHMODE_NATIVE) {
1173                         CtdlRegisterProtoHook(cmd_oids, "OIDS", "Setup OpenID authentication");
1174                         CtdlRegisterProtoHook(cmd_oidf, "OIDF", "Finalize OpenID authentication");
1175                         CtdlRegisterProtoHook(cmd_oidl, "OIDL", "List OpenIDs associated with an account");
1176                         CtdlRegisterProtoHook(cmd_oidd, "OIDD", "Detach an OpenID from an account");
1177                         CtdlRegisterProtoHook(cmd_oidc, "OIDC", "Create new user after validating OpenID");
1178                         CtdlRegisterProtoHook(cmd_oida, "OIDA", "List all OpenIDs in the database");
1179                 }
1180                 CtdlRegisterSessionHook(openid_cleanup_function, EVT_LOGOUT, PRIO_LOGOUT + 10);
1181                 CtdlRegisterUserHook(openid_purge, EVT_PURGEUSER);
1182                 openid_level_supported = 1;     /* This module supports OpenID 1.0 only */
1183         }
1184
1185         /* return our module name for the log */
1186         return "openid_rp";
1187 }