If the X-XRDS-Location header is found, put it into a StrBuf instead of a char[]
[citadel.git] / citadel / modules / openid / serv_openid_rp.c
1 /*
2  * This is an implementation of OpenID 2.0 RELYING PARTY SUPPORT CURRENTLY B0RKEN AND BEING DEVEL0PZ0RED
3  *
4  * Copyright (c) 2007-2011 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 *claimed_id;
53         StrBuf *server;
54         int verified;
55         HashList *sreg_keys;
56 } ctdl_openid;
57
58 void Free_ctdl_openid(ctdl_openid **FreeMe)
59 {
60         if (*FreeMe == NULL)
61                 return;
62         FreeStrBuf(&(*FreeMe)->claimed_id);
63         FreeStrBuf(&(*FreeMe)->server);
64         DeleteHash(&(*FreeMe)->sreg_keys);
65         free(*FreeMe);
66         *FreeMe = NULL;
67 }
68
69
70 /*
71  * This cleanup function blows away the temporary memory used by this module.
72  */
73 void openid_cleanup_function(void) {
74         struct CitContext *CCC = CC;    /* CachedCitContext - performance boost */
75
76         if (CCC->openid_data != NULL) {
77                 syslog(LOG_DEBUG, "Clearing OpenID session state");
78                 Free_ctdl_openid((ctdl_openid **) &CCC->openid_data);
79         }
80 }
81
82
83 /**************************************************************************/
84 /*                                                                        */
85 /* Functions in this section handle Citadel internal OpenID mapping stuff */
86 /*                                                                        */
87 /**************************************************************************/
88
89
90 /*
91  * The structure of an openid record *key* is:
92  *
93  * |--------------claimed_id-------------|
94  *     (actual length of claimed id)
95  *
96  *
97  * The structure of an openid record *value* is:
98  *
99  * |-----user_number----|------------claimed_id---------------|
100  *    (sizeof long)          (actual length of claimed id)
101  *
102  */
103
104
105
106 /*
107  * Attach an OpenID to a Citadel account
108  */
109 int attach_openid(struct ctdluser *who, StrBuf *claimed_id)
110 {
111         struct cdbdata *cdboi;
112         long fetched_usernum;
113         char *data;
114         int data_len;
115         char buf[2048];
116
117         if (!who) return(1);
118         if (StrLength(claimed_id)==0) return(1);
119
120         /* Check to see if this OpenID is already in the database */
121
122         cdboi = cdb_fetch(CDB_OPENID, ChrPtr(claimed_id), StrLength(claimed_id));
123         if (cdboi != NULL) {
124                 memcpy(&fetched_usernum, cdboi->ptr, sizeof(long));
125                 cdb_free(cdboi);
126
127                 if (fetched_usernum == who->usernum) {
128                         syslog(LOG_INFO, "%s already associated; no action is taken", ChrPtr(claimed_id));
129                         return(0);
130                 }
131                 else {
132                         syslog(LOG_INFO, "%s already belongs to another user", ChrPtr(claimed_id));
133                         return(3);
134                 }
135         }
136
137         /* Not already in the database, so attach it now */
138
139         data_len = sizeof(long) + StrLength(claimed_id) + 1;
140         data = malloc(data_len);
141
142         memcpy(data, &who->usernum, sizeof(long));
143         memcpy(&data[sizeof(long)], ChrPtr(claimed_id), StrLength(claimed_id) + 1);
144
145         cdb_store(CDB_OPENID, ChrPtr(claimed_id), StrLength(claimed_id), data, data_len);
146         free(data);
147
148         snprintf(buf, sizeof buf, "User <%s> (#%ld) has claimed the OpenID URL %s\n",
149                  who->fullname, who->usernum, ChrPtr(claimed_id));
150         CtdlAideMessage(buf, "OpenID claim");
151         syslog(LOG_INFO, "%s", buf);
152         return(0);
153 }
154
155
156
157 /*
158  * When a user is being deleted, we have to delete any OpenID associations
159  */
160 void openid_purge(struct ctdluser *usbuf) {
161         struct cdbdata *cdboi;
162         HashList *keys = NULL;
163         HashPos *HashPos;
164         char *deleteme = NULL;
165         long len;
166         void *Value;
167         const char *Key;
168         long usernum = 0L;
169
170         keys = NewHash(1, NULL);
171         if (!keys) return;
172
173         cdb_rewind(CDB_OPENID);
174         while (cdboi = cdb_next_item(CDB_OPENID), cdboi != NULL) {
175                 if (cdboi->len > sizeof(long)) {
176                         memcpy(&usernum, cdboi->ptr, sizeof(long));
177                         if (usernum == usbuf->usernum) {
178                                 deleteme = strdup(cdboi->ptr + sizeof(long)),
179                                 Put(keys, deleteme, strlen(deleteme), deleteme, NULL);
180                         }
181                 }
182                 cdb_free(cdboi);
183         }
184
185         /* Go through the hash list, deleting keys we stored in it */
186
187         HashPos = GetNewHashPos(keys, 0);
188         while (GetNextHashPos(keys, HashPos, &len, &Key, &Value)!=0)
189         {
190                 syslog(LOG_DEBUG, "Deleting associated OpenID <%s>", (char*)Value);
191                 cdb_delete(CDB_OPENID, Value, strlen(Value));
192                 /* note: don't free(Value) -- deleting the hash list will handle this for us */
193         }
194         DeleteHashPos(&HashPos);
195         DeleteHash(&keys);
196 }
197
198
199 /*
200  * List the OpenIDs associated with the currently logged in account
201  */
202 void cmd_oidl(char *argbuf) {
203         struct cdbdata *cdboi;
204         long usernum = 0L;
205
206         if (CtdlAccessCheck(ac_logged_in)) return;
207         cdb_rewind(CDB_OPENID);
208         cprintf("%d Associated OpenIDs:\n", LISTING_FOLLOWS);
209
210         while (cdboi = cdb_next_item(CDB_OPENID), cdboi != NULL) {
211                 if (cdboi->len > sizeof(long)) {
212                         memcpy(&usernum, cdboi->ptr, sizeof(long));
213                         if (usernum == CC->user.usernum) {
214                                 cprintf("%s\n", cdboi->ptr + sizeof(long));
215                         }
216                 }
217                 cdb_free(cdboi);
218         }
219         cprintf("000\n");
220 }
221
222
223 /*
224  * List ALL OpenIDs in the database
225  */
226 void cmd_oida(char *argbuf) {
227         struct cdbdata *cdboi;
228         long usernum;
229         struct ctdluser usbuf;
230
231         if (CtdlAccessCheck(ac_aide)) return;
232         cdb_rewind(CDB_OPENID);
233         cprintf("%d List of all OpenIDs in the database:\n", LISTING_FOLLOWS);
234
235         while (cdboi = cdb_next_item(CDB_OPENID), cdboi != NULL) {
236                 if (cdboi->len > sizeof(long)) {
237                         memcpy(&usernum, cdboi->ptr, sizeof(long));
238                         if (CtdlGetUserByNumber(&usbuf, usernum) != 0) {
239                                 usbuf.fullname[0] = 0;
240                         } 
241                         cprintf("%s|%ld|%s\n",
242                                 cdboi->ptr + sizeof(long),
243                                 usernum,
244                                 usbuf.fullname
245                         );
246                 }
247                 cdb_free(cdboi);
248         }
249         cprintf("000\n");
250 }
251
252
253 /*
254  * Attempt to register (populate the vCard) the currently-logged-in user
255  * using the data from Simple Registration Extension, if present.
256  */
257 void populate_vcard_from_sreg(HashList *sreg_keys) {
258
259         struct vCard *v;
260         int pop = 0;                    /* number of fields populated */
261         char *data = NULL;
262         char *postcode = NULL;
263         char *country = NULL;
264
265         if (!sreg_keys) return;
266         v = vcard_new();
267         if (!v) return;
268
269         if (GetHash(sreg_keys, "identity", 8, (void *) &data)) {
270                 vcard_add_prop(v, "url;type=openid", data);
271                 ++pop;
272         }
273
274         if (GetHash(sreg_keys, "sreg.email", 10, (void *) &data)) {
275                 vcard_add_prop(v, "email;internet", data);
276                 ++pop;
277         }
278
279         if (GetHash(sreg_keys, "sreg.nickname", 13, (void *) &data)) {
280                 vcard_add_prop(v, "nickname", data);
281                 ++pop;
282         }
283
284         if (GetHash(sreg_keys, "sreg.fullname", 13, (void *) &data)) {
285                 char n[256];
286                 vcard_add_prop(v, "fn", data);
287                 vcard_fn_to_n(n, data, sizeof n);
288                 vcard_add_prop(v, "n", n);
289                 ++pop;
290         }
291
292         if (!GetHash(sreg_keys, "sreg.postcode", 13, (void *) &postcode)) {
293                 postcode = NULL;
294         }
295
296         if (!GetHash(sreg_keys, "sreg.country", 12, (void *) &country)) {
297                 country = NULL;
298         }
299
300         if (postcode || country) {
301                 char adr[256];
302                 snprintf(adr, sizeof adr, ";;;;;%s;%s",
303                         (postcode ? postcode : ""),
304                         (country ? country : "")
305                 );
306                 vcard_add_prop(v, "adr", adr);
307                 ++pop;
308         }
309
310         if (GetHash(sreg_keys, "sreg.dob", 8, (void *) &data)) {
311                 vcard_add_prop(v, "bday", data);
312                 ++pop;
313         }
314
315         if (GetHash(sreg_keys, "sreg.gender", 11, (void *) &data)) {
316                 vcard_add_prop(v, "x-funambol-gender", data);
317                 ++pop;
318         }
319
320         /* Only save the vCard if there is some useful data in it */
321         if (pop > 0) {
322                 char *ser;
323                 ser = vcard_serialize(v);
324                 if (ser) {
325                         CtdlWriteObject(USERCONFIGROOM, "text/x-vcard",
326                                 ser, strlen(ser)+1, &CC->user, 0, 0, 0
327                         );
328                         free(ser);
329                 }
330         }
331         vcard_free(v);
332 }
333
334
335 /*
336  * Create a new user account, manually specifying the name, after successfully
337  * verifying an OpenID (which will of course be attached to the account)
338  */
339 void cmd_oidc(char *argbuf) {
340         ctdl_openid *oiddata = (ctdl_openid *) CC->openid_data;
341
342         if (!oiddata) {
343                 cprintf("%d You have not verified an OpenID yet.\n", ERROR);
344                 return;
345         }
346
347         if (!oiddata->verified) {
348                 cprintf("%d You have not verified an OpenID yet.\n", ERROR);
349                 return;
350         }
351
352         /* We can make the semantics of OIDC exactly the same as NEWU, simply
353          * by _calling_ cmd_newu() and letting it run.  Very clever!
354          */
355         cmd_newu(argbuf);
356
357         /* Now, if this logged us in, we have to attach the OpenID */
358         if (CC->logged_in) {
359                 attach_openid(&CC->user, oiddata->claimed_id);
360                 if (oiddata->sreg_keys != NULL) {
361                         populate_vcard_from_sreg(oiddata->sreg_keys);
362                 }
363         }
364
365 }
366
367
368 /*
369  * Detach an OpenID from the currently logged in account
370  */
371 void cmd_oidd(char *argbuf) {
372         struct cdbdata *cdboi;
373         char id_to_detach[1024];
374         int this_is_mine = 0;
375         long usernum = 0L;
376
377         if (CtdlAccessCheck(ac_logged_in)) return;
378         extract_token(id_to_detach, argbuf, 0, '|', sizeof id_to_detach);
379         if (IsEmptyStr(id_to_detach)) {
380                 cprintf("%d An empty OpenID URL is not allowed.\n", ERROR + ILLEGAL_VALUE);
381         }
382
383         cdb_rewind(CDB_OPENID);
384         while (cdboi = cdb_next_item(CDB_OPENID), cdboi != NULL) {
385                 if (cdboi->len > sizeof(long)) {
386                         memcpy(&usernum, cdboi->ptr, sizeof(long));
387                         if (usernum == CC->user.usernum) {
388                                 this_is_mine = 1;
389                         }
390                 }
391                 cdb_free(cdboi);
392         }
393
394         if (!this_is_mine) {
395                 cprintf("%d That OpenID was not found or not associated with your account.\n",
396                         ERROR + ILLEGAL_VALUE);
397                 return;
398         }
399
400         cdb_delete(CDB_OPENID, id_to_detach, strlen(id_to_detach));
401         cprintf("%d %s detached from your account.\n", CIT_OK, id_to_detach);
402 }
403
404
405
406 /*
407  * Attempt to auto-create a new Citadel account using the nickname from Simple Registration Extension
408  */
409 int openid_create_user_via_sreg(StrBuf *claimed_id, HashList *sreg_keys)
410 {
411         char *desired_name = NULL;
412         char new_password[32];
413         long len;
414
415         if (config.c_auth_mode != AUTHMODE_NATIVE) return(1);
416         if (config.c_disable_newu) return(2);
417         if (CC->logged_in) return(3);
418         if (!GetHash(sreg_keys, "sreg.nickname", 13, (void *) &desired_name)) return(4);
419
420         syslog(LOG_DEBUG, "The desired account name is <%s>", desired_name);
421
422         len = cutuserkey(desired_name);
423         if (!CtdlGetUser(&CC->user, desired_name)) {
424                 syslog(LOG_DEBUG, "<%s> is already taken by another user.", desired_name);
425                 memset(&CC->user, 0, sizeof(struct ctdluser));
426                 return(5);
427         }
428
429         /* The desired account name is available.  Create the account and log it in! */
430         if (create_user(desired_name, len, 1)) return(6);
431
432         snprintf(new_password, sizeof new_password, "%08lx%08lx", random(), random());
433         CtdlSetPassword(new_password);
434         attach_openid(&CC->user, claimed_id);
435         populate_vcard_from_sreg(sreg_keys);
436         return(0);
437 }
438
439
440 /*
441  * If a user account exists which is associated with the Claimed ID, log it in and return zero.
442  * Otherwise it returns nonzero.
443  */
444 int login_via_openid(StrBuf *claimed_id)
445 {
446         struct cdbdata *cdboi;
447         long usernum = 0;
448
449         cdboi = cdb_fetch(CDB_OPENID, ChrPtr(claimed_id), StrLength(claimed_id));
450         if (cdboi == NULL) {
451                 return(-1);
452         }
453
454         memcpy(&usernum, cdboi->ptr, sizeof(long));
455         cdb_free(cdboi);
456
457         if (!CtdlGetUserByNumber(&CC->user, usernum)) {
458                 /* Now become the user we just created */
459                 safestrncpy(CC->curr_user, CC->user.fullname, sizeof CC->curr_user);
460                 do_login();
461                 return(0);
462         }
463         else {
464                 memset(&CC->user, 0, sizeof(struct ctdluser));
465                 return(-1);
466         }
467 }
468
469
470
471
472 /**************************************************************************/
473 /*                                                                        */
474 /* Functions in this section handle OpenID protocol                       */
475 /*                                                                        */
476 /**************************************************************************/
477
478
479 /* 
480  * Locate a <link> tag and, given its 'rel=' parameter, return its 'href' parameter
481  */
482 void extract_link(StrBuf *target_buf, const char *rel, long repllen, StrBuf *source_buf)
483 {
484         int i;
485         const char *ptr;
486         const char *href_start = NULL;
487         const char *href_end = NULL;
488         const char *link_tag_start = NULL;
489         const char *link_tag_end = NULL;
490         const char *rel_start = NULL;
491         const char *rel_end = NULL;
492
493         if (!target_buf) return;
494         if (!rel) return;
495         if (!source_buf) return;
496
497         ptr = ChrPtr(source_buf);
498
499         FlushStrBuf(target_buf);
500         while (ptr = cbmstrcasestr(ptr, "<link"), ptr != NULL) {
501
502                 link_tag_start = ptr;
503                 link_tag_end = strchr(ptr, '>');
504                 if (link_tag_end == NULL)
505                         break;
506                 for (i=0; i < 1; i++ ){
507                         rel_start = cbmstrcasestr(link_tag_start, "rel=");
508                         if ((rel_start == NULL) ||
509                             (rel_start > link_tag_end)) 
510                                 continue;
511
512                         rel_start = strchr(rel_start, '\"');
513                         if ((rel_start == NULL) ||
514                             (rel_start > link_tag_end)) 
515                                 continue;
516                         ++rel_start;
517                         rel_end = strchr(rel_start, '\"');
518                         if ((rel_end == NULL) ||
519                             (rel_end == rel_start) ||
520                             (rel_end >= link_tag_end) ) 
521                                 continue;
522                         if (strncasecmp(rel, rel_start, repllen)!= 0)
523                                 continue; /* didn't match? never mind... */
524                         
525                         href_start = cbmstrcasestr(link_tag_start, "href=");
526                         if ((href_start == NULL) || 
527                             (href_start >= link_tag_end)) 
528                                 continue;
529                         href_start = strchr(href_start, '\"');
530                         if ((href_start == NULL) |
531                             (href_start >= link_tag_end)) 
532                                 continue;
533                         ++href_start;
534                         href_end = strchr(href_start, '\"');
535                         if ((href_end == NULL) || 
536                             (href_end == href_start) ||
537                             (href_start >= link_tag_end)) 
538                                 continue;
539                         StrBufPlain(target_buf, href_start, href_end - href_start);
540                 }
541                 ptr = link_tag_end;     
542         }
543 }
544
545
546 /*
547  * Wrapper for curl_easy_init() that includes the options common to all calls
548  * used in this module. 
549  */
550 CURL *ctdl_openid_curl_easy_init(char *errmsg) {
551         CURL *curl;
552
553         curl = curl_easy_init();
554         if (!curl) {
555                 return(curl);
556         }
557
558         curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0);
559         curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0);
560
561         if (errmsg) {
562                 curl_easy_setopt(curl, CURLOPT_ERRORBUFFER, errmsg);
563         }
564         curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1);
565 #ifdef CURLOPT_HTTP_CONTENT_DECODING
566         curl_easy_setopt(curl, CURLOPT_HTTP_CONTENT_DECODING, 1);
567         curl_easy_setopt(curl, CURLOPT_ENCODING, "");
568 #endif
569         curl_easy_setopt(curl, CURLOPT_USERAGENT, CITADEL);
570         curl_easy_setopt(curl, CURLOPT_TIMEOUT, 30);            /* die after 30 seconds */
571
572         if (
573                 (!IsEmptyStr(config.c_ip_addr))
574                 && (strcmp(config.c_ip_addr, "*"))
575                 && (strcmp(config.c_ip_addr, "::"))
576                 && (strcmp(config.c_ip_addr, "0.0.0.0"))
577         ) {
578                 curl_easy_setopt(curl, CURLOPT_INTERFACE, config.c_ip_addr);
579         }
580
581         return(curl);
582 }
583
584
585 /*
586  * Begin an HTTP fetch (returns number of bytes actually fetched, or -1 for error) using libcurl.
587  */
588 int fetch_http(StrBuf *url, StrBuf **target_buf)
589 {
590         StrBuf *ReplyBuf;
591         CURL *curl;
592         CURLcode result;
593         char *effective_url = NULL;
594         char errmsg[1024] = "";
595
596         if (StrLength(url) <=0 ) return(-1);
597         ReplyBuf = *target_buf = NewStrBuf ();
598         if (ReplyBuf == 0) return(-1);
599
600         curl = ctdl_openid_curl_easy_init(errmsg);
601         if (!curl) return(-1);
602
603         curl_easy_setopt(curl, CURLOPT_URL, ChrPtr(url));
604         curl_easy_setopt(curl, CURLOPT_WRITEDATA, ReplyBuf);
605         curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, CurlFillStrBuf_callback);
606
607         result = curl_easy_perform(curl);
608         if (result) {
609                 syslog(LOG_DEBUG, "libcurl error %d: %s", result, errmsg);
610         }
611         curl_easy_getinfo(curl, CURLINFO_EFFECTIVE_URL, &effective_url);
612         StrBufPlain(url, effective_url, -1);
613         
614         curl_easy_cleanup(curl);
615         return StrLength(ReplyBuf);
616 }
617
618
619
620 struct xrds {
621         int nesting_level;
622         int in_xrd;
623         int current_service_priority;
624         int selected_service_priority;  /* more here later */
625 };
626
627
628 void xrds_xml_start(void *data, const char *supplied_el, const char **attr) {
629         struct xrds *xrds = (struct xrds *) data;
630         int i;
631
632         ++xrds->nesting_level;
633
634         if (!strcasecmp(supplied_el, "XRD")) {
635                 ++xrds->in_xrd;
636                 syslog(LOG_DEBUG, "*** XRD CONTAINER BEGIN ***");
637         }
638
639         else if (!strcasecmp(supplied_el, "service")) {
640                 xrds->current_service_priority = 0;
641                 for (i=0; attr[i] != NULL; i+=2) {
642                         if (!strcasecmp(attr[i], "priority")) {
643                                 xrds->current_service_priority = atoi(attr[i+1]);
644                         }
645                 }
646         }
647 }
648
649
650 void xrds_xml_end(void *data, const char *supplied_el) {
651         struct xrds *xrds = (struct xrds *) data;
652
653         --xrds->nesting_level;
654
655         if (!strcasecmp(supplied_el, "XRD")) {
656                 --xrds->in_xrd;
657                 syslog(LOG_DEBUG, "*** XRD CONTAINER END ***");
658         }
659
660         else if (!strcasecmp(supplied_el, "service")) {
661                 /* this is where we should evaluate the service and do stuff */
662                 xrds->current_service_priority = 0;
663         }
664 }
665
666
667 void xrds_xml_chardata(void *data, const XML_Char *s, int len) {
668         struct xrds *xrds = (struct xrds *) data;
669
670         if (xrds) ;     /* this is only here to silence the warning for now */
671         
672         /* StrBufAppendBufPlain (xrds->CData, s, len, 0); */
673 }
674
675
676 /*
677  * Parse an XRDS document.
678  * If OpenID stuff is discovered, populate FIXME something and return nonzero
679  * If nothing useful happened, return 0.
680  */
681 int parse_xrds_document(StrBuf *ReplyBuf) {
682         struct xrds xrds;
683
684         memset(&xrds, 0, sizeof (struct xrds));
685         XML_Parser xp = XML_ParserCreate(NULL);
686         if (xp) {
687                 XML_SetUserData(xp, &xrds);
688                 XML_SetElementHandler(xp, xrds_xml_start, xrds_xml_end);
689                 XML_SetCharacterDataHandler(xp, xrds_xml_chardata);
690                 XML_Parse(xp, ChrPtr(ReplyBuf), StrLength(ReplyBuf), 0);
691                 XML_Parse(xp, "", 0, 1);
692                 XML_ParserFree(xp);
693         }
694         else {
695                 syslog(LOG_ALERT, "Cannot create XML parser");
696         }
697
698         return(0);      /* FIXME return nonzero if something wonderful happened */
699 }
700
701
702
703 /*
704  * Callback function for perform_yadis_discovery()
705  * We're interested in HTTP headers returned from the server.
706  */
707 size_t yadis_headerfunction(void *ptr, size_t size, size_t nmemb, void *userdata) {
708         char hdr[1024];
709         StrBuf **x_xrds_location = (StrBuf **) userdata;
710
711         memcpy(hdr, ptr, (size*nmemb));
712         hdr[size*nmemb] = 0;
713
714         /* We are looking for a header like this:
715          * X-XRDS-Location: https://api.screenname.aol.com/auth/openid/xrds
716          */
717         if (!strncasecmp(hdr, "X-XRDS-Location:", 16)) {
718                 *x_xrds_location = NewStrBufPlain(&hdr[16], ((size*nmemb)-16));
719                 StrBufTrim(*x_xrds_location);
720         }
721
722         return(size * nmemb);
723 }
724
725
726
727 /* Attempt to perform Yadis discovery as specified in Yadis 1.0 section 6.2.5.
728  * If successful, returns nonzero and calls parse_xrds_document() to act upon the received data.
729  * If Yadis fails, returns 0 and does nothing else.
730  */
731 int perform_yadis_discovery(StrBuf *YadisURL) {
732         int docbytes = (-1);
733         StrBuf *ReplyBuf = NULL;
734         int r;
735         CURL *curl;
736         CURLcode result;
737         char errmsg[1024] = "";
738         struct curl_slist *my_headers = NULL;
739         StrBuf *x_xrds_location = NULL;
740
741         if (YadisURL == NULL) return(0);
742         if (StrLength(YadisURL) == 0) return(0);
743
744         ReplyBuf = NewStrBuf ();
745         if (ReplyBuf == 0) 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(YadisURL));
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         /* FIXME handle this somehow */
776
777         /*
778          * Option 2: HTTP response-headers that include an X-XRDS-Location response-header,
779          *           together with a document.
780          * Option 3: HTTP response-headers only, which MAY include an X-XRDS-Location response-header,
781          *           a contenttype response-header specifying MIME media type,
782          *           application/xrds+xml, or both.
783          *
784          * If the X-XRDS-Location header was delivered, we know about it at this point...
785          */
786         if (x_xrds_location) {
787                 syslog(LOG_DEBUG, "\033[31m FIXME \033[32m'%s'\033[0m", ChrPtr(x_xrds_location));
788                 FreeStrBuf(&x_xrds_location);
789         }
790
791         /*
792          * Option 4: the returned web page may *be* an XRDS document.  Try to parse it.
793          */
794         r = 0;
795         if (docbytes >= 0) {
796                 r = parse_xrds_document(ReplyBuf);
797                 FreeStrBuf(&ReplyBuf);
798         }
799
800         return(r);
801 }
802
803
804 /*
805  * Setup an OpenID authentication
806  */
807 void cmd_oids(char *argbuf) {
808         const char *Pos = NULL;
809         StrBuf *ArgBuf = NULL;
810         StrBuf *ReplyBuf = NULL;
811         StrBuf *return_to = NULL;
812         StrBuf *trust_root = NULL;
813         StrBuf *openid_delegate = NULL;
814         StrBuf *RedirectUrl = NULL;
815         struct CitContext *CCC = CC;    /* CachedCitContext - performance boost */
816         ctdl_openid *oiddata;
817
818         Free_ctdl_openid ((ctdl_openid**)&CCC->openid_data);
819
820         CCC->openid_data = oiddata = malloc(sizeof(ctdl_openid));
821         if (oiddata == NULL) {
822                 cprintf("%d malloc failed\n", ERROR + INTERNAL_ERROR);
823                 return;
824         }
825         memset(oiddata, 0, sizeof(ctdl_openid));
826         CCC->openid_data = (void *) oiddata;
827
828         ArgBuf = NewStrBufPlain(argbuf, -1);
829
830         oiddata->verified = 0;
831         oiddata->claimed_id = NewStrBufPlain(NULL, StrLength(ArgBuf));
832         trust_root = NewStrBufPlain(NULL, StrLength(ArgBuf));
833         return_to = NewStrBufPlain(NULL, StrLength(ArgBuf));
834
835         StrBufExtract_NextToken(oiddata->claimed_id, ArgBuf, &Pos, '|');
836         StrBufExtract_NextToken(return_to, ArgBuf, &Pos, '|');
837         StrBufExtract_NextToken(trust_root, ArgBuf, &Pos, '|');
838
839         syslog(LOG_DEBUG, "User-Supplied Identifier is: %s", ChrPtr(oiddata->claimed_id));
840
841
842         /********** OpenID 2.0 section 7.3 - Discovery **********/
843
844         /* First we're supposed to attempt XRI based resolution.
845          * No one is using this, no one is asking for it, no one wants it.
846          * So we're not even going to bother attempting this mode.
847          */
848
849         /* Second we attempt Yadis.
850          * Google uses this so we'd better do our best to implement it.
851          */
852         int yadis_succeeded = perform_yadis_discovery(oiddata->claimed_id);
853
854         /* Third we attempt HTML-based discovery.  Here we go! */
855         if (    (yadis_succeeded == 0)
856                 && (fetch_http(oiddata->claimed_id, &ReplyBuf) > 0)
857                 && (StrLength(ReplyBuf) > 0)
858         ) {
859                 openid_delegate = NewStrBuf();
860                 oiddata->server = NewStrBuf();
861                 extract_link(oiddata->server, HKEY("openid.server"), ReplyBuf);
862                 extract_link(openid_delegate, HKEY("openid.delegate"), ReplyBuf);
863
864                 if (StrLength(oiddata->server) == 0) {
865                         cprintf("%d There is no OpenID identity provider at this URL.\n", ERROR);
866                         FreeStrBuf(&ArgBuf);
867                         FreeStrBuf(&ReplyBuf);
868                         FreeStrBuf(&return_to);
869                         FreeStrBuf(&trust_root);
870                         FreeStrBuf(&openid_delegate);
871                         FreeStrBuf(&RedirectUrl);
872                         return;
873                 }
874
875                 /* Empty delegate is legal; we just use the openid_url instead */
876                 if (StrLength(openid_delegate) == 0) {
877                         StrBufPlain(openid_delegate, SKEY(oiddata->claimed_id));
878                 }
879
880                 /* Assemble a URL to which the user-agent will be redirected. */
881
882                 RedirectUrl = NewStrBufDup(oiddata->server);
883
884                 StrBufAppendBufPlain(RedirectUrl, HKEY("?openid.mode=checkid_setup"
885                                                        "&openid.identity="), 0);
886                 StrBufUrlescAppend(RedirectUrl, openid_delegate, NULL);
887
888                 StrBufAppendBufPlain(RedirectUrl, HKEY("&openid.return_to="), 0);
889                 StrBufUrlescAppend(RedirectUrl, return_to, NULL);
890
891                 StrBufAppendBufPlain(RedirectUrl, HKEY("&openid.trust_root="), 0);
892                 StrBufUrlescAppend(RedirectUrl, trust_root, NULL);
893
894                 StrBufAppendBufPlain(RedirectUrl, HKEY("&openid.sreg.optional="), 0);
895                 StrBufUrlescAppend(RedirectUrl, NULL, "nickname,email,fullname,postcode,country,dob,gender");
896
897                 cprintf("%d %s\n", CIT_OK, ChrPtr(RedirectUrl));
898                 
899                 FreeStrBuf(&ArgBuf);
900                 FreeStrBuf(&ReplyBuf);
901                 FreeStrBuf(&return_to);
902                 FreeStrBuf(&trust_root);
903                 FreeStrBuf(&openid_delegate);
904                 FreeStrBuf(&RedirectUrl);
905
906                 return;
907         }
908
909         FreeStrBuf(&ArgBuf);
910         FreeStrBuf(&ReplyBuf);
911         FreeStrBuf(&return_to);
912         FreeStrBuf(&trust_root);
913         FreeStrBuf(&openid_delegate);
914         FreeStrBuf(&RedirectUrl);
915
916         cprintf("%d Unable to fetch OpenID URL\n", ERROR);
917 }
918
919
920
921
922
923 /*
924  * Finalize an OpenID authentication
925  */
926 void cmd_oidf(char *argbuf) {
927         long len;
928         char buf[2048];
929         char thiskey[1024];
930         char thisdata[1024];
931         HashList *keys = NULL;
932         ctdl_openid *oiddata = (ctdl_openid *) CC->openid_data;
933
934         if (oiddata == NULL) {
935                 cprintf("%d run OIDS first.\n", ERROR + INTERNAL_ERROR);
936                 return;
937         }
938         if (StrLength(oiddata->server) == 0){
939                 cprintf("%d need a remote server to authenticate against\n", ERROR + ILLEGAL_VALUE);
940                 return;
941         }
942         keys = NewHash(1, NULL);
943         if (!keys) {
944                 cprintf("%d NewHash() failed\n", ERROR + INTERNAL_ERROR);
945                 return;
946         }
947         cprintf("%d Transmit OpenID data now\n", START_CHAT_MODE);
948
949         while (client_getln(buf, sizeof buf), strcmp(buf, "000")) {
950                 len = extract_token(thiskey, buf, 0, '|', sizeof thiskey);
951                 if (len < 0)
952                         len = sizeof(thiskey) - 1;
953                 extract_token(thisdata, buf, 1, '|', sizeof thisdata);
954                 syslog(LOG_DEBUG, "%s: ["SIZE_T_FMT"] %s", thiskey, strlen(thisdata), thisdata);
955                 Put(keys, thiskey, len, strdup(thisdata), NULL);
956         }
957
958
959         /* Now that we have all of the parameters, we have to validate the signature against the server */
960         syslog(LOG_DEBUG, "About to validate the signature...");
961
962         CURL *curl;
963         CURLcode res;
964         struct curl_httppost *formpost = NULL;
965         struct curl_httppost *lastptr = NULL;
966         char errmsg[1024] = "";
967         char *o_assoc_handle = NULL;
968         char *o_sig = NULL;
969         char *o_signed = NULL;
970         int num_signed_values;
971         int i;
972         char k_keyname[128];
973         char k_o_keyname[128];
974         char *k_value = NULL;
975         StrBuf *ReplyBuf;
976
977         curl_formadd(&formpost, &lastptr,
978                 CURLFORM_COPYNAME,      "openid.mode",
979                 CURLFORM_COPYCONTENTS,  "check_authentication",
980                 CURLFORM_END);
981         syslog(LOG_DEBUG, "%25s : %s", "openid.mode", "check_authentication");
982
983         if (GetHash(keys, "assoc_handle", 12, (void *) &o_assoc_handle)) {
984                 curl_formadd(&formpost, &lastptr,
985                         CURLFORM_COPYNAME,      "openid.assoc_handle",
986                         CURLFORM_COPYCONTENTS,  o_assoc_handle,
987                         CURLFORM_END);
988                 syslog(LOG_DEBUG, "%25s : %s", "openid.assoc_handle", o_assoc_handle);
989         }
990
991         if (GetHash(keys, "sig", 3, (void *) &o_sig)) {
992                 curl_formadd(&formpost, &lastptr,
993                         CURLFORM_COPYNAME,      "openid.sig",
994                         CURLFORM_COPYCONTENTS,  o_sig,
995                         CURLFORM_END);
996                         syslog(LOG_DEBUG, "%25s : %s", "openid.sig", o_sig);
997         }
998
999         if (GetHash(keys, "signed", 6, (void *) &o_signed)) {
1000                 curl_formadd(&formpost, &lastptr,
1001                         CURLFORM_COPYNAME,      "openid.signed",
1002                         CURLFORM_COPYCONTENTS,  o_signed,
1003                         CURLFORM_END);
1004                 syslog(LOG_DEBUG, "%25s : %s", "openid.signed", o_signed);
1005
1006                 num_signed_values = num_tokens(o_signed, ',');
1007                 for (i=0; i<num_signed_values; ++i) {
1008                         extract_token(k_keyname, o_signed, i, ',', sizeof k_keyname);
1009                         if (strcasecmp(k_keyname, "mode")) {    // work around phpMyID bug
1010                                 if (GetHash(keys, k_keyname, strlen(k_keyname), (void *) &k_value)) {
1011                                         snprintf(k_o_keyname, sizeof k_o_keyname, "openid.%s", k_keyname);
1012                                         curl_formadd(&formpost, &lastptr,
1013                                                 CURLFORM_COPYNAME,      k_o_keyname,
1014                                                 CURLFORM_COPYCONTENTS,  k_value,
1015                                                 CURLFORM_END);
1016                                         syslog(LOG_DEBUG, "%25s : %s", k_o_keyname, k_value);
1017                                 }
1018                                 else {
1019                                         syslog(LOG_INFO, "OpenID: signed field '%s' is missing",
1020                                                 k_keyname);
1021                                 }
1022                         }
1023                 }
1024         }
1025         
1026         ReplyBuf = NewStrBuf();
1027
1028         curl = ctdl_openid_curl_easy_init(errmsg);
1029         curl_easy_setopt(curl, CURLOPT_URL, ChrPtr(oiddata->server));
1030         curl_easy_setopt(curl, CURLOPT_WRITEDATA, ReplyBuf);
1031         curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, CurlFillStrBuf_callback);
1032         curl_easy_setopt(curl, CURLOPT_HTTPPOST, formpost);
1033
1034         res = curl_easy_perform(curl);
1035         if (res) {
1036                 syslog(LOG_DEBUG, "cmd_oidf() libcurl error %d: %s", res, errmsg);
1037         }
1038         curl_easy_cleanup(curl);
1039         curl_formfree(formpost);
1040
1041         if (cbmstrcasestr(ChrPtr(ReplyBuf), "is_valid:true")) {
1042                 oiddata->verified = 1;
1043         }
1044         FreeStrBuf(&ReplyBuf);
1045
1046         syslog(LOG_DEBUG, "Authentication %s.", (oiddata->verified ? "succeeded" : "failed") );
1047
1048         /* Respond to the client */
1049
1050         if (oiddata->verified) {
1051
1052                 /* If we were already logged in, attach the OpenID to the user's account */
1053                 if (CC->logged_in) {
1054                         if (attach_openid(&CC->user, oiddata->claimed_id) == 0) {
1055                                 cprintf("attach\n");
1056                                 syslog(LOG_DEBUG, "OpenID attach succeeded");
1057                         }
1058                         else {
1059                                 cprintf("fail\n");
1060                                 syslog(LOG_DEBUG, "OpenID attach failed");
1061                         }
1062                 }
1063
1064                 /* Otherwise, a user is attempting to log in using the verified OpenID */       
1065                 else {
1066                         /*
1067                          * Existing user who has claimed this OpenID?
1068                          *
1069                          * Note: if you think that sending the password back over the wire is insecure,
1070                          * check your assumptions.  If someone has successfully asserted an OpenID that
1071                          * is associated with the account, they already have password equivalency and can
1072                          * login, so they could just as easily change the password, etc.
1073                          */
1074                         if (login_via_openid(oiddata->claimed_id) == 0) {
1075                                 cprintf("authenticate\n%s\n%s\n", CC->user.fullname, CC->user.password);
1076                                 logged_in_response();
1077                                 syslog(LOG_DEBUG, "Logged in using previously claimed OpenID");
1078                         }
1079
1080                         /*
1081                          * If this system does not allow self-service new user registration, the
1082                          * remaining modes do not apply, so fail here and now.
1083                          */
1084                         else if (config.c_disable_newu) {
1085                                 cprintf("fail\n");
1086                                 syslog(LOG_DEBUG, "Creating user failed due to local policy");
1087                         }
1088
1089                         /*
1090                          * New user whose OpenID is verified and Simple Registration Extension is in use?
1091                          */
1092                         else if (openid_create_user_via_sreg(oiddata->claimed_id, keys) == 0) {
1093                                 cprintf("authenticate\n%s\n%s\n", CC->user.fullname, CC->user.password);
1094                                 logged_in_response();
1095                                 syslog(LOG_DEBUG, "Successfully auto-created new user");
1096                         }
1097
1098                         /*
1099                          * OpenID is verified, but the desired username either was not specified or
1100                          * conflicts with an existing user.  Manual account creation is required.
1101                          */
1102                         else {
1103                                 char *desired_name = NULL;
1104                                 cprintf("verify_only\n");
1105                                 cprintf("%s\n", ChrPtr(oiddata->claimed_id));
1106                                 if (GetHash(keys, "sreg.nickname", 13, (void *) &desired_name)) {
1107                                         cprintf("%s\n", desired_name);
1108                                 }
1109                                 else {
1110                                         cprintf("\n");
1111                                 }
1112                                 syslog(LOG_DEBUG, "The desired Simple Registration name is already taken.");
1113                         }
1114                 }
1115         }
1116         else {
1117                 cprintf("fail\n");
1118         }
1119         cprintf("000\n");
1120
1121         if (oiddata->sreg_keys != NULL) {
1122                 DeleteHash(&oiddata->sreg_keys);
1123                 oiddata->sreg_keys = NULL;
1124         }
1125         oiddata->sreg_keys = keys;
1126 }
1127
1128
1129
1130 /**************************************************************************/
1131 /*                                                                        */
1132 /* Functions in this section handle module initialization and shutdown    */
1133 /*                                                                        */
1134 /**************************************************************************/
1135
1136
1137
1138
1139 CTDL_MODULE_INIT(openid_rp)
1140 {
1141         if (!threading) {
1142                 curl_global_init(CURL_GLOBAL_ALL);
1143
1144                 /* Only enable the OpenID command set when native mode authentication is in use. */
1145                 if (config.c_auth_mode == AUTHMODE_NATIVE) {
1146                         CtdlRegisterProtoHook(cmd_oids, "OIDS", "Setup OpenID authentication");
1147                         CtdlRegisterProtoHook(cmd_oidf, "OIDF", "Finalize OpenID authentication");
1148                         CtdlRegisterProtoHook(cmd_oidl, "OIDL", "List OpenIDs associated with an account");
1149                         CtdlRegisterProtoHook(cmd_oidd, "OIDD", "Detach an OpenID from an account");
1150                         CtdlRegisterProtoHook(cmd_oidc, "OIDC", "Create new user after validating OpenID");
1151                         CtdlRegisterProtoHook(cmd_oida, "OIDA", "List all OpenIDs in the database");
1152                 }
1153                 CtdlRegisterSessionHook(openid_cleanup_function, EVT_LOGOUT);
1154                 CtdlRegisterUserHook(openid_purge, EVT_PURGEUSER);
1155                 openid_level_supported = 1;     /* This module supports OpenID 1.0 only */
1156         }
1157
1158         /* return our module name for the log */
1159         return "openid_rp";
1160 }