2.59
utils.c
1/* snac - A simple, minimalistic ActivityPub instance */
2/* copyright (c) 2022 - 2024 grunfink et al. / MIT license */
3
4#include "xs.h"
5#include "xs_io.h"
6#include "xs_json.h"
7#include "xs_time.h"
8#include "xs_openssl.h"
9#include "xs_random.h"
10#include "xs_glob.h"
11#include "xs_curl.h"
12#include "xs_regex.h"
13
14#include "snac.h"
15
16#include <sys/stat.h>
17#include <stdlib.h>
18
19static const char *default_srv_config = "{"
20 "\"host\": \"\","
21 "\"prefix\": \"\","
22 "\"address\": \"127.0.0.1\","
23 "\"port\": 8001,"
24 "\"layout\": 0.0,"
25 "\"dbglevel\": 0,"
26 "\"queue_retry_minutes\": 2,"
27 "\"queue_retry_max\": 10,"
28 "\"queue_timeout\": 6,"
29 "\"queue_timeout_2\": 8,"
30 "\"cssurls\": [\"\"],"
31 "\"max_timeline_entries\": 50,"
32 "\"timeline_purge_days\": 120,"
33 "\"local_purge_days\": 0,"
34 "\"min_account_age\": 0,"
35 "\"admin_email\": \"\","
36 "\"admin_account\": \"\","
37 "\"title\": \"\","
38 "\"short_description\": \"\","
39 "\"protocol\": \"https\","
40 "\"fastcgi\": false"
41 "}";
42
43static const char *default_css =
44 "body { max-width: 48em; margin: auto; line-height: 1.5; padding: 0.8em; word-wrap: break-word; }\n"
45 "pre { overflow-x: scroll; }\n"
46 ".snac-embedded-video, img { max-width: 100% }\n"
47 ".snac-origin { font-size: 85% }\n"
48 ".snac-score { float: right; font-size: 85% }\n"
49 ".snac-top-user { text-align: center; padding-bottom: 2em }\n"
50 ".snac-top-user-name { font-size: 200% }\n"
51 ".snac-top-user-id { font-size: 150% }\n"
52 ".snac-announcement { border: black 1px solid; padding: 0.5em }\n"
53 ".snac-avatar { float: left; height: 2.5em; width: 2.5em; padding: 0.25em }\n"
54 ".snac-author { font-size: 90%; text-decoration: none }\n"
55 ".snac-author-tag { font-size: 80% }\n"
56 ".snac-pubdate { color: #a0a0a0; font-size: 90% }\n"
57 ".snac-top-controls { padding-bottom: 1.5em }\n"
58 ".snac-post { border-top: 1px solid #a0a0a0; padding-top: 0.5em; padding-bottom: 0.5em; }\n"
59 ".snac-children { padding-left: 1em; border-left: 1px solid #a0a0a0; }\n"
60 ".snac-textarea { font-family: inherit; width: 100% }\n"
61 ".snac-history { border: 1px solid #606060; border-radius: 3px; margin: 2.5em 0; padding: 0 2em }\n"
62 ".snac-btn-mute { float: right; margin-left: 0.5em }\n"
63 ".snac-btn-unmute { float: right; margin-left: 0.5em }\n"
64 ".snac-btn-follow { float: right; margin-left: 0.5em }\n"
65 ".snac-btn-unfollow { float: right; margin-left: 0.5em }\n"
66 ".snac-btn-hide { float: right; margin-left: 0.5em }\n"
67 ".snac-btn-delete { float: right; margin-left: 0.5em }\n"
68 ".snac-btn-limit { float: right; margin-left: 0.5em }\n"
69 ".snac-btn-unlimit { float: right; margin-left: 0.5em }\n"
70 ".snac-footer { margin-top: 2em; font-size: 75% }\n"
71 ".snac-poll-result { margin-left: auto; margin-right: auto; }\n"
72 ".snac-list-of-lists { padding-left: 0; }\n"
73 ".snac-list-of-lists li { display: inline; border: 1px solid #a0a0a0; border-radius: 25px;\n"
74 " margin-right: 0.5em; padding-left: 0.5em; padding-right: 0.5em; }\n"
75 "@media (prefers-color-scheme: dark) { \n"
76 " body, input, textarea { background-color: #000; color: #fff; }\n"
77 " a { color: #7799dd }\n"
78 " a:visited { color: #aa99dd }\n"
79 "}\n"
80;
81
82const char *snac_blurb =
83 "<p><b>%host%</b> is a <a href=\"https:/"
84 "/en.wikipedia.org/wiki/Fediverse\">Fediverse</a> "
85 "instance that uses the <a href=\"https:/"
86 "/en.wikipedia.org/wiki/ActivityPub\">ActivityPub</a> "
87 "protocol. In other words, users at this host can communicate with people "
88 "that use software like Mastodon, Pleroma, Friendica, etc. "
89 "all around the world.</p>\n"
90 "<p>This server runs the "
91 "<a href=\"" WHAT_IS_SNAC_URL "\">snac</a> software and there is no "
92 "automatic sign-up process.</p>\n"
93;
94
95static const char *greeting_html =
96 "<!DOCTYPE html>\n"
97 "<html><head>\n"
98 "<meta name=\"viewport\" content=\"width=device-width, initial-scale=1\"/>\n"
99 "<link rel=\"icon\" type=\"image/x-icon\" href=\"https://%host%/favicon.ico\"/>\n"
100 "<title>Welcome to %host%</title>\n"
101 "<body style=\"margin: auto; max-width: 50em\">\n"
102 "%blurb%"
103 "<p>The following users are part of this community:</p>\n"
104 "\n"
105 "%userlist%\n"
106 "\n"
107 "<p>This site is powered by <abbr title=\"Social Networks Are Crap\">snac</abbr>.</p>\n"
108 "</body></html>\n";
109
110
111int write_default_css(void)
112{
113 FILE *f;
114
115 xs *sfn = xs_fmt("%s/style.css", srv_basedir);
116 if ((f = fopen(sfn, "w")) == NULL)
117 return 1;
118
119 fwrite(default_css, strlen(default_css), 1, f);
120 fclose(f);
121
122 return 0;
123}
124
125
126int snac_init(const char *basedir)
127{
128 FILE *f;
129
130 if (basedir == NULL) {
131 printf("Base directory: "); fflush(stdout);
132 srv_basedir = xs_strip_i(xs_readline(stdin));
133 }
134 else
135 srv_basedir = xs_str_new(basedir);
136
137 if (srv_basedir == NULL || *srv_basedir == '\0')
138 return 1;
139
140 if (xs_endswith(srv_basedir, "/"))
141 srv_basedir = xs_crop_i(srv_basedir, 0, -1);
142
143 if (mtime(srv_basedir) != 0.0) {
144 printf("ERROR: directory '%s' must not exist.\n", srv_basedir);
145 return 1;
146 }
147
148 srv_config = xs_json_loads(default_srv_config);
149
150 xs *layout = xs_number_new(disk_layout);
151 srv_config = xs_dict_set(srv_config, "layout", layout);
152
153 int is_unix_socket = 0;
154
155 printf("Network address or full path to unix socket [%s]: ", xs_dict_get(srv_config, "address")); fflush(stdout);
156 {
157 xs *i = xs_strip_i(xs_readline(stdin));
158 if (*i) {
159 srv_config = xs_dict_set(srv_config, "address", i);
160
161 if (*i == '/')
162 is_unix_socket = 1;
163 }
164 }
165
166 if (!is_unix_socket) {
167 printf("Network port [%d]: ", (int)xs_number_get(xs_dict_get(srv_config, "port"))); fflush(stdout);
168 {
169 xs *i = xs_strip_i(xs_readline(stdin));
170 if (*i) {
171 xs *n = xs_number_new(atoi(i));
172 srv_config = xs_dict_set(srv_config, "port", n);
173 }
174 }
175 }
176 else {
177 xs *n = xs_number_new(0);
178 srv_config = xs_dict_set(srv_config, "port", n);
179 }
180
181 printf("Host name: "); fflush(stdout);
182 {
183 xs *i = xs_strip_i(xs_readline(stdin));
184 if (*i == '\0')
185 return 1;
186
187 srv_config = xs_dict_set(srv_config, "host", i);
188 }
189
190 printf("URL prefix: "); fflush(stdout);
191 {
192 xs *i = xs_strip_i(xs_readline(stdin));
193
194 if (*i) {
195 if (xs_endswith(i, "/"))
196 i = xs_crop_i(i, 0, -1);
197
198 srv_config = xs_dict_set(srv_config, "prefix", i);
199 }
200 }
201
202 printf("Admin email address (optional): "); fflush(stdout);
203 {
204 xs *i = xs_strip_i(xs_readline(stdin));
205
206 srv_config = xs_dict_set(srv_config, "admin_email", i);
207 }
208
209 if (mkdirx(srv_basedir) == -1) {
210 printf("ERROR: cannot create directory '%s'\n", srv_basedir);
211 return 1;
212 }
213
214 xs *udir = xs_fmt("%s/user", srv_basedir);
215 mkdirx(udir);
216
217 xs *odir = xs_fmt("%s/object", srv_basedir);
218 mkdirx(odir);
219
220 xs *qdir = xs_fmt("%s/queue", srv_basedir);
221 mkdirx(qdir);
222
223 xs *ibdir = xs_fmt("%s/inbox", srv_basedir);
224 mkdirx(ibdir);
225
226 xs *gfn = xs_fmt("%s/greeting.html", srv_basedir);
227 if ((f = fopen(gfn, "w")) == NULL) {
228 printf("ERROR: cannot create '%s'\n", gfn);
229 return 1;
230 }
231
232 xs *gh = xs_replace(greeting_html, "%blurb%", snac_blurb);
233 fwrite(gh, strlen(gh), 1, f);
234 fclose(f);
235
236 if (write_default_css()) {
237 printf("ERROR: cannot create style.css\n");
238 return 1;
239 }
240
241 xs *cfn = xs_fmt("%s/server.json", srv_basedir);
242 if ((f = fopen(cfn, "w")) == NULL) {
243 printf("ERROR: cannot create '%s'\n", cfn);
244 return 1;
245 }
246
247 xs_json_dump(srv_config, 4, f);
248 fclose(f);
249
250 printf("Done.\n");
251 return 0;
252}
253
254
255void new_password(const char *uid, xs_str **clear_pwd, xs_str **hashed_pwd)
256/* creates a random password */
257{
258 int rndbuf[3];
259
260 xs_rnd_buf(rndbuf, sizeof(rndbuf));
261
262 *clear_pwd = xs_base64_enc((char *)rndbuf, sizeof(rndbuf));
263 *hashed_pwd = hash_password(uid, *clear_pwd, NULL);
264}
265
266
267int adduser(const char *uid)
268/* creates a new user */
269{
270 snac snac;
271 xs *config = xs_dict_new();
272 xs *date = xs_str_utctime(0, ISO_DATE_SPEC);
273 xs *pwd = NULL;
274 xs *pwd_f = NULL;
275 xs *key = NULL;
276 FILE *f;
277
278 if (uid == NULL) {
279 printf("Username: "); fflush(stdout);
280 uid = xs_strip_i(xs_readline(stdin));
281 }
282
283 if (!validate_uid(uid)) {
284 printf("ERROR: only alphanumeric characters and _ are allowed in user ids.\n");
285 return 1;
286 }
287
288 if (user_open(&snac, uid)) {
289 printf("ERROR: user '%s' already exists\n", snac.uid);
290 return 1;
291 }
292
293 new_password(uid, &pwd, &pwd_f);
294
295 config = xs_dict_append(config, "uid", uid);
296 config = xs_dict_append(config, "name", uid);
297 config = xs_dict_append(config, "avatar", "");
298 config = xs_dict_append(config, "bio", "");
299 config = xs_dict_append(config, "cw", "");
300 config = xs_dict_append(config, "published", date);
301 config = xs_dict_append(config, "passwd", pwd_f);
302
303 xs *basedir = xs_fmt("%s/user/%s", srv_basedir, uid);
304
305 if (mkdirx(basedir) == -1) {
306 printf("ERROR: cannot create directory '%s'\n", basedir);
307 return 0;
308 }
309
310 const char *dirs[] = {
311 "followers", "following", "muted", "hidden",
312 "public", "private", "queue", "history",
313 "static", NULL };
314 int n;
315
316 for (n = 0; dirs[n]; n++) {
317 xs *d = xs_fmt("%s/%s", basedir, dirs[n]);
318 mkdirx(d);
319 }
320
321 xs *cfn = xs_fmt("%s/user.json", basedir);
322
323 if ((f = fopen(cfn, "w")) == NULL) {
324 printf("ERROR: cannot create '%s'\n", cfn);
325 return 1;
326 }
327 else {
328 xs_json_dump(config, 4, f);
329 fclose(f);
330 }
331
332 printf("\nCreating RSA key...\n");
333 key = xs_evp_genkey(4096);
334 printf("Done.\n");
335
336 xs *kfn = xs_fmt("%s/key.json", basedir);
337
338 if ((f = fopen(kfn, "w")) == NULL) {
339 printf("ERROR: cannot create '%s'\n", kfn);
340 return 1;
341 }
342 else {
343 xs_json_dump(key, 4, f);
344 fclose(f);
345 }
346
347 printf("\nUser password is %s\n", pwd);
348
349 printf("\nGo to %s/%s and continue configuring your user there.\n", srv_baseurl, uid);
350
351 return 0;
352}
353
354
355int resetpwd(snac *snac)
356/* creates a new password for the user */
357{
358 xs *clear_pwd = NULL;
359 xs *hashed_pwd = NULL;
360 xs *fn = xs_fmt("%s/user.json", snac->basedir);
361 FILE *f;
362 int ret = 0;
363
364 new_password(snac->uid, &clear_pwd, &hashed_pwd);
365
366 snac->config = xs_dict_set(snac->config, "passwd", hashed_pwd);
367
368 if ((f = fopen(fn, "w")) != NULL) {
369 xs_json_dump(snac->config, 4, f);
370 fclose(f);
371
372 printf("New password for user %s is %s\n", snac->uid, clear_pwd);
373 }
374 else {
375 printf("ERROR: cannot write to %s\n", fn);
376 ret = 1;
377 }
378
379 return ret;
380}
381
382
383void rm_rf(const char *dir)
384/* does an rm -rf (yes, I'm also scared) */
385{
386 xs *d = xs_str_cat(xs_dup(dir), "/" "*");
387 xs *l = xs_glob(d, 0, 0);
388 xs_list *p = l;
389 const xs_str *v;
390
391 if (dbglevel >= 1)
392 printf("Deleting directory %s\n", dir);
393
394 while (xs_list_iter(&p, &v)) {
395 struct stat st;
396
397 if (stat(v, &st) != -1) {
398 if (st.st_mode & S_IFDIR) {
399 rm_rf(v);
400 }
401 else {
402 if (dbglevel >= 1)
403 printf("Deleting file %s\n", v);
404
405 if (unlink(v) == -1)
406 printf("ERROR: cannot delete file %s\n", v);
407 }
408 }
409 else
410 printf("ERROR: stat() fail for %s\n", v);
411 }
412
413 if (rmdir(dir) == -1)
414 printf("ERROR: cannot delete directory %s\n", dir);
415}
416
417
418int deluser(snac *user)
419/* deletes a user */
420{
421 int ret = 0;
422 xs *fwers = following_list(user);
423 xs_list *p = fwers;
424 const xs_str *v;
425
426 while (xs_list_iter(&p, &v)) {
427 xs *object = NULL;
428
429 if (valid_status(following_get(user, v, &object))) {
430 xs *msg = msg_undo(user, xs_dict_get(object, "object"));
431
432 following_del(user, v);
433
434 enqueue_output_by_actor(user, msg, v, 0);
435
436 printf("Unfollowing actor %s\n", v);
437 }
438 }
439
440 rm_rf(user->basedir);
441
442 return ret;
443}
444
445
446void verify_links(snac *user)
447/* verifies a user's links */
448{
449 const xs_dict *p = xs_dict_get(user->config, "metadata");
450 const char *k, *v;
451 int changed = 0;
452
453 xs *headers = xs_dict_new();
454 headers = xs_dict_append(headers, "accept", "text/html");
455 headers = xs_dict_append(headers, "user-agent", USER_AGENT " (link verify)");
456
457 int c = 0;
458 while (p && xs_dict_next(p, &k, &v, &c)) {
459 /* not an https link? skip */
460 if (!xs_startswith(v, "https:/" "/"))
461 continue;
462
463 int status;
464 xs *req = NULL;
465 xs *payload = NULL;
466 int p_size = 0;
467
468 req = xs_http_request("GET", v, headers, NULL, 0, &status,
469 &payload, &p_size, 0);
470
471 if (!valid_status(status)) {
472 snac_log(user, xs_fmt("link %s verify error %d", v, status));
473 continue;
474 }
475
476 /* extract the links */
477 xs *ls = xs_regex_select(payload, "< *(a|link) +[^>]+>");
478
479 xs_list *lp = ls;
480 const char *ll;
481 int vfied = 0;
482
483 while (!vfied && xs_list_iter(&lp, &ll)) {
484 /* extract href and rel */
485 xs *r = xs_regex_select(ll, "(href|rel) *= *(\"[^\"]*\"|'[^']*')");
486
487 /* must have both attributes */
488 if (xs_list_len(r) != 2)
489 continue;
490
491 xs *href = NULL;
492 int is_rel_me = 0;
493 xs_list *pr = r;
494 const char *ar;
495
496 while (xs_list_iter(&pr, &ar)) {
497 xs *nq = xs_dup(ar);
498
499 nq = xs_replace_i(nq, "\"", "");
500 nq = xs_replace_i(nq, "'", "");
501
502 xs *r2 = xs_split_n(nq, "=", 1);
503 if (xs_list_len(r2) != 2)
504 continue;
505
506 xs *ak = xs_strip_i(xs_dup(xs_list_get(r2, 0)));
507 xs *av = xs_strip_i(xs_dup(xs_list_get(r2, 1)));
508
509 if (strcmp(ak, "href") == 0)
510 href = xs_dup(av);
511 else
512 if (strcmp(ak, "rel") == 0) {
513 /* split the value by spaces */
514 xs *vbs = xs_split(av, " ");
515
516 /* is any of it "me"? */
517 if (xs_list_in(vbs, "me") != -1)
518 is_rel_me = 1;
519 }
520 }
521
522 /* after all this acrobatics, do we have an href and a rel="me"? */
523 if (href != NULL && is_rel_me) {
524 /* is it the same as the actor? */
525 if (strcmp(href, user->actor) == 0) {
526 /* got it! */
527 xs *verified_time = xs_number_new((double)time(NULL));
528
529 if (user->links == NULL)
530 user->links = xs_dict_new();
531
532 user->links = xs_dict_set(user->links, v, verified_time);
533
534 vfied = 1;
535 }
536 else
537 snac_debug(user, 1,
538 xs_fmt("verify link %s rel='me' found but not related (%s)", v, href));
539 }
540 }
541
542 if (vfied) {
543 changed++;
544 snac_log(user, xs_fmt("link %s verified", v));
545 }
546 else {
547 snac_log(user, xs_fmt("link %s not verified (rel='me' not found)", v));
548 }
549 }
550
551 if (changed) {
552 FILE *f;
553
554 /* update the links.json file */
555 xs *fn = xs_fmt("%s/links.json", user->basedir);
556 xs *bfn = xs_fmt("%s.bak", fn);
557
558 rename(fn, bfn);
559
560 if ((f = fopen(fn, "w")) != NULL) {
561 xs_json_dump(user->links, 4, f);
562 fclose(f);
563 }
564 else
565 rename(bfn, fn);
566 }
567}
