Welcome to %host%

/* snac - A simple, minimalistic ActivityPub instance */ /* copyright (c) 2022 - 2024 grunfink et al. / MIT license */ #include "xs.h" #include "xs_io.h" #include "xs_json.h" #include "xs_time.h" #include "xs_openssl.h" #include "xs_random.h" #include "xs_glob.h" #include "xs_curl.h" #include "xs_regex.h" #include "snac.h" #include #include static const char *default_srv_config = "{" "\"host\": \"\"," "\"prefix\": \"\"," "\"address\": \"127.0.0.1\"," "\"port\": 8001," "\"layout\": 0.0," "\"dbglevel\": 0," "\"queue_retry_minutes\": 2," "\"queue_retry_max\": 10," "\"cssurls\": [\"\"]," "\"max_timeline_entries\": 128," "\"timeline_purge_days\": 120," "\"local_purge_days\": 0," "\"admin_email\": \"\"," "\"admin_account\": \"\"," "\"title\": \"\"," "\"short_description\": \"\"," "\"fastcgi\": false" "}"; static const char *default_css = "body { max-width: 48em; margin: auto; line-height: 1.5; padding: 0.8em; word-wrap: break-word; }\n" "pre { overflow-x: scroll; }\n" ".snac-embedded-video, img { max-width: 100% }\n" ".snac-origin { font-size: 85% }\n" ".snac-score { float: right; font-size: 85% }\n" ".snac-top-user { text-align: center; padding-bottom: 2em }\n" ".snac-top-user-name { font-size: 200% }\n" ".snac-top-user-id { font-size: 150% }\n" ".snac-avatar { float: left; height: 2.5em; padding: 0.25em }\n" ".snac-author { font-size: 90%; text-decoration: none }\n" ".snac-author-tag { font-size: 80% }\n" ".snac-pubdate { color: #a0a0a0; font-size: 90% }\n" ".snac-top-controls { padding-bottom: 1.5em }\n" ".snac-post { border-top: 1px solid #a0a0a0; }\n" ".snac-children { padding-left: 2em; border-left: 1px solid #a0a0a0; }\n" ".snac-textarea { font-family: inherit; width: 100% }\n" ".snac-history { border: 1px solid #606060; border-radius: 3px; margin: 2.5em 0; padding: 0 2em }\n" ".snac-btn-mute { float: right; margin-left: 0.5em }\n" ".snac-btn-unmute { float: right; margin-left: 0.5em }\n" ".snac-btn-follow { float: right; margin-left: 0.5em }\n" ".snac-btn-unfollow { float: right; margin-left: 0.5em }\n" ".snac-btn-hide { float: right; margin-left: 0.5em }\n" ".snac-btn-delete { float: right; margin-left: 0.5em }\n" ".snac-btn-limit { float: right; margin-left: 0.5em }\n" ".snac-btn-unlimit { float: right; margin-left: 0.5em }\n" ".snac-footer { margin-top: 2em; font-size: 75% }\n" ".snac-poll-result { margin-left: auto; margin-right: auto; }\n" "@media (prefers-color-scheme: dark) { \n" " body { background-color: #000; color: #fff; }\n" " a { color: #7799dd }\n" " a:visited { color: #aa99dd }\n" "}\n" ; const char *snac_blurb = "

%host% is a Fediverse " "instance that uses the ActivityPub " "protocol. In other words, users at this host can communicate with people " "that use software like Mastodon, Pleroma, Friendica, etc. " "all around the world.

\n" "

This server runs the " "snac software and there is no " "automatic sign-up process.

\n" ; static const char *greeting_html = "\n" "\n" "\n" "\n" "Welcome to %host%\n" "\n" "%blurb%" "

The following users are part of this community:

\n" "\n" "%userlist%\n" "\n" "

This site is powered by snac.

\n" "\n"; int snac_init(const char *basedir) { FILE *f; if (basedir == NULL) { printf("Base directory: "); fflush(stdout); srv_basedir = xs_strip_i(xs_readline(stdin)); } else srv_basedir = xs_str_new(basedir); if (srv_basedir == NULL || *srv_basedir == '\0') return 1; if (xs_endswith(srv_basedir, "/")) srv_basedir = xs_crop_i(srv_basedir, 0, -1); if (mtime(srv_basedir) != 0.0) { printf("ERROR: directory '%s' must not exist.\n", srv_basedir); return 1; } srv_config = xs_json_loads(default_srv_config); xs *layout = xs_number_new(disk_layout); srv_config = xs_dict_set(srv_config, "layout", layout); printf("Network address [%s]: ", xs_dict_get(srv_config, "address")); fflush(stdout); { xs *i = xs_strip_i(xs_readline(stdin)); if (*i) srv_config = xs_dict_set(srv_config, "address", i); } printf("Network port [%d]: ", (int)xs_number_get(xs_dict_get(srv_config, "port"))); fflush(stdout); { xs *i = xs_strip_i(xs_readline(stdin)); if (*i) { xs *n = xs_number_new(atoi(i)); srv_config = xs_dict_set(srv_config, "port", n); } } printf("Host name: "); fflush(stdout); { xs *i = xs_strip_i(xs_readline(stdin)); if (*i == '\0') return 1; srv_config = xs_dict_set(srv_config, "host", i); } printf("URL prefix: "); fflush(stdout); { xs *i = xs_strip_i(xs_readline(stdin)); if (*i) { if (xs_endswith(i, "/")) i = xs_crop_i(i, 0, -1); srv_config = xs_dict_set(srv_config, "prefix", i); } } printf("Admin email address (optional): "); fflush(stdout); { xs *i = xs_strip_i(xs_readline(stdin)); srv_config = xs_dict_set(srv_config, "admin_email", i); } if (mkdirx(srv_basedir) == -1) { printf("ERROR: cannot create directory '%s'\n", srv_basedir); return 1; } xs *udir = xs_fmt("%s/user", srv_basedir); mkdirx(udir); xs *odir = xs_fmt("%s/object", srv_basedir); mkdirx(odir); xs *qdir = xs_fmt("%s/queue", srv_basedir); mkdirx(qdir); xs *ibdir = xs_fmt("%s/inbox", srv_basedir); mkdirx(ibdir); xs *gfn = xs_fmt("%s/greeting.html", srv_basedir); if ((f = fopen(gfn, "w")) == NULL) { printf("ERROR: cannot create '%s'\n", gfn); return 1; } xs *gh = xs_replace(greeting_html, "%blurb%", snac_blurb); fwrite(gh, strlen(gh), 1, f); fclose(f); xs *sfn = xs_fmt("%s/style.css", srv_basedir); if ((f = fopen(sfn, "w")) == NULL) { printf("ERROR: cannot create '%s'\n", sfn); return 1; } fwrite(default_css, strlen(default_css), 1, f); fclose(f); xs *cfn = xs_fmt("%s/server.json", srv_basedir); if ((f = fopen(cfn, "w")) == NULL) { printf("ERROR: cannot create '%s'\n", cfn); return 1; } xs_json_dump(srv_config, 4, f); fclose(f); printf("Done.\n"); return 0; } void new_password(const char *uid, xs_str **clear_pwd, xs_str **hashed_pwd) /* creates a random password */ { int rndbuf[3]; xs_rnd_buf(rndbuf, sizeof(rndbuf)); *clear_pwd = xs_base64_enc((char *)rndbuf, sizeof(rndbuf)); *hashed_pwd = hash_password(uid, *clear_pwd, NULL); } int adduser(const char *uid) /* creates a new user */ { snac snac; xs *config = xs_dict_new(); xs *date = xs_str_utctime(0, ISO_DATE_SPEC); xs *pwd = NULL; xs *pwd_f = NULL; xs *key = NULL; FILE *f; if (uid == NULL) { printf("Username: "); fflush(stdout); uid = xs_strip_i(xs_readline(stdin)); } if (!validate_uid(uid)) { printf("ERROR: only alphanumeric characters and _ are allowed in user ids.\n"); return 1; } if (user_open(&snac, uid)) { printf("ERROR: user '%s' already exists\n", snac.uid); return 1; } new_password(uid, &pwd, &pwd_f); config = xs_dict_append(config, "uid", uid); config = xs_dict_append(config, "name", uid); config = xs_dict_append(config, "avatar", ""); config = xs_dict_append(config, "bio", ""); config = xs_dict_append(config, "cw", ""); config = xs_dict_append(config, "published", date); config = xs_dict_append(config, "passwd", pwd_f); xs *basedir = xs_fmt("%s/user/%s", srv_basedir, uid); if (mkdirx(basedir) == -1) { printf("ERROR: cannot create directory '%s'\n", basedir); return 0; } const char *dirs[] = { "followers", "following", "muted", "hidden", "public", "private", "queue", "history", "static", NULL }; int n; for (n = 0; dirs[n]; n++) { xs *d = xs_fmt("%s/%s", basedir, dirs[n]); mkdirx(d); } xs *cfn = xs_fmt("%s/user.json", basedir); if ((f = fopen(cfn, "w")) == NULL) { printf("ERROR: cannot create '%s'\n", cfn); return 1; } else { xs_json_dump(config, 4, f); fclose(f); } printf("\nCreating RSA key...\n"); key = xs_evp_genkey(4096); printf("Done.\n"); xs *kfn = xs_fmt("%s/key.json", basedir); if ((f = fopen(kfn, "w")) == NULL) { printf("ERROR: cannot create '%s'\n", kfn); return 1; } else { xs_json_dump(key, 4, f); fclose(f); } printf("\nUser password is %s\n", pwd); printf("\nGo to %s/%s and continue configuring your user there.\n", srv_baseurl, uid); return 0; } int resetpwd(snac *snac) /* creates a new password for the user */ { xs *clear_pwd = NULL; xs *hashed_pwd = NULL; xs *fn = xs_fmt("%s/user.json", snac->basedir); FILE *f; int ret = 0; new_password(snac->uid, &clear_pwd, &hashed_pwd); snac->config = xs_dict_set(snac->config, "passwd", hashed_pwd); if ((f = fopen(fn, "w")) != NULL) { xs_json_dump(snac->config, 4, f); fclose(f); printf("New password for user %s is %s\n", snac->uid, clear_pwd); } else { printf("ERROR: cannot write to %s\n", fn); ret = 1; } return ret; } void rm_rf(const char *dir) /* does an rm -rf (yes, I'm also scared) */ { xs *d = xs_str_cat(xs_dup(dir), "/" "*"); xs *l = xs_glob(d, 0, 0); xs_list *p = l; xs_str *v; if (dbglevel >= 1) printf("Deleting directory %s\n", dir); while (xs_list_iter(&p, &v)) { struct stat st; if (stat(v, &st) != -1) { if (st.st_mode & S_IFDIR) { rm_rf(v); } else { if (dbglevel >= 1) printf("Deleting file %s\n", v); if (unlink(v) == -1) printf("ERROR: cannot delete file %s\n", v); } } else printf("ERROR: stat() fail for %s\n", v); } if (rmdir(dir) == -1) printf("ERROR: cannot delete directory %s\n", dir); } int deluser(snac *user) /* deletes a user */ { int ret = 0; xs *fwers = following_list(user); xs_list *p = fwers; xs_str *v; while (xs_list_iter(&p, &v)) { xs *object = NULL; if (valid_status(following_get(user, v, &object))) { xs *msg = msg_undo(user, xs_dict_get(object, "object")); following_del(user, v); enqueue_output_by_actor(user, msg, v, 0); printf("Unfollowing actor %s\n", v); } } rm_rf(user->basedir); return ret; } void verify_links(snac *user) /* verifies a user's links */ { xs_dict *p = xs_dict_get(user->config, "metadata"); char *k, *v; int changed = 0; xs *headers = xs_dict_new(); headers = xs_dict_append(headers, "accept", "text/html"); headers = xs_dict_append(headers, "user-agent", USER_AGENT " (link verify)"); while (p && xs_dict_iter(&p, &k, &v)) { /* not an https link? skip */ if (!xs_startswith(v, "https:/" "/")) continue; int status; xs *req = NULL; xs *payload = NULL; int p_size = 0; req = xs_http_request("GET", v, headers, NULL, 0, &status, &payload, &p_size, 0); if (!valid_status(status)) { snac_log(user, xs_fmt("link %s verify error %d", v, status)); continue; } /* extract the links */ xs *ls = xs_regex_select(payload, "< *(a|link) +[^>]+>"); xs_list *lp = ls; char *ll; int vfied = 0; while (!vfied && xs_list_iter(&lp, &ll)) { /* extract href and rel */ xs *r = xs_regex_select(ll, "(href|rel) *= *(\"[^\"]*\"|'[^']*')"); /* must have both attributes */ if (xs_list_len(r) != 2) continue; xs *href = NULL; int is_rel_me = 0; xs_list *pr = r; char *ar; while (xs_list_iter(&pr, &ar)) { xs *nq = xs_dup(ar); nq = xs_replace_i(nq, "\"", ""); nq = xs_replace_i(nq, "'", ""); xs *r2 = xs_split_n(nq, "=", 1); if (xs_list_len(r2) != 2) continue; xs *ak = xs_strip_i(xs_dup(xs_list_get(r2, 0))); xs *av = xs_strip_i(xs_dup(xs_list_get(r2, 1))); if (strcmp(ak, "href") == 0) href = xs_dup(av); else if (strcmp(ak, "rel") == 0) { /* split the value by spaces */ xs *vbs = xs_split(av, " "); /* is any of it "me"? */ if (xs_list_in(vbs, "me") != -1) is_rel_me = 1; } } /* after all this acrobatics, do we have an href and a rel="me"? */ if (href != NULL && is_rel_me) { /* is it the same as the actor? */ if (strcmp(href, user->actor) == 0) { /* got it! */ xs *verified_at = xs_str_utctime(0, ISO_DATE_SPEC); if (user->links == NULL) user->links = xs_dict_new(); user->links = xs_dict_set(user->links, v, verified_at); vfied = 1; } else snac_debug(user, 1, xs_fmt("verify link %s rel='me' found but not related (%s)", v, href)); } } if (vfied) { changed++; snac_log(user, xs_fmt("link %s verified", v)); } else { snac_log(user, xs_fmt("link %s not verified (rel='me' not found)", v)); } } if (changed) { FILE *f; /* update the links.json file */ xs *fn = xs_fmt("%s/links.json", user->basedir); xs *bfn = xs_fmt("%s.bak", fn); rename(fn, bfn); if ((f = fopen(fn, "w")) != NULL) { xs_json_dump(user->links, 4, f); fclose(f); } else rename(bfn, fn); } }