/* snac - A simple, minimalistic ActivityPub instance */ /* copyright (c) 2022 - 2023 grunfink / MIT license */ #include "xs.h" #include "xs_encdec.h" #include "xs_openssl.h" #include "xs_json.h" #include "xs_io.h" #include "xs_time.h" #include "snac.h" static xs_str *random_str(void) /* just what is says in the tin */ { unsigned int data[4] = {0}; FILE *f; if ((f = fopen("/dev/random", "r")) != NULL) { fread(data, sizeof(data), 1, f); fclose(f); } else { data[0] = random() % 0xffffffff; data[1] = random() % 0xffffffff; data[2] = random() % 0xffffffff; data[3] = random() % 0xffffffff; } return xs_hex_enc((char *)data, sizeof(data)); } int app_add(const char *id, const xs_dict *app) /* stores an app */ { if (!xs_is_hex(id)) return 500; int status = 201; xs *fn = xs_fmt("%s/app/", srv_basedir); FILE *f; mkdirx(fn); fn = xs_str_cat(fn, id); fn = xs_str_cat(fn, ".json"); if ((f = fopen(fn, "w")) != NULL) { xs *j = xs_json_dumps_pp(app, 4); fwrite(j, strlen(j), 1, f); fclose(f); } else status = 500; return status; } xs_dict *app_get(const char *id) /* gets an app */ { if (!xs_is_hex(id)) return NULL; xs *fn = xs_fmt("%s/app/%s.json", srv_basedir, id); xs_dict *app = NULL; FILE *f; if ((f = fopen(fn, "r")) != NULL) { xs *j = xs_readall(f); fclose(f); app = xs_json_loads(j); } return app; } int app_del(const char *id) /* deletes an app */ { if (!xs_is_hex(id)) return -1; xs *fn = xs_fmt("%s/app/%s.json", srv_basedir, id); return unlink(fn); } int token_add(const char *id, const xs_dict *token) /* stores a token */ { if (!xs_is_hex(id)) return 500; int status = 201; xs *fn = xs_fmt("%s/token/", srv_basedir); FILE *f; mkdirx(fn); fn = xs_str_cat(fn, id); fn = xs_str_cat(fn, ".json"); if ((f = fopen(fn, "w")) != NULL) { xs *j = xs_json_dumps_pp(token, 4); fwrite(j, strlen(j), 1, f); fclose(f); } else status = 500; return status; } xs_dict *token_get(const char *id) /* gets a token */ { if (!xs_is_hex(id)) return NULL; xs *fn = xs_fmt("%s/token/%s.json", srv_basedir, id); xs_dict *token = NULL; FILE *f; if ((f = fopen(fn, "r")) != NULL) { xs *j = xs_readall(f); fclose(f); token = xs_json_loads(j); } return token; } int token_del(const char *id) /* deletes a token */ { if (!xs_is_hex(id)) return -1; xs *fn = xs_fmt("%s/token/%s.json", srv_basedir, id); return unlink(fn); } const char *login_page = "" "\n" "

%s OAuth identify

\n" "

\n" ""; int oauth_get_handler(const xs_dict *req, const char *q_path, char **body, int *b_size, char **ctype) { if (!xs_startswith(q_path, "/oauth/")) return 0; { xs *j = xs_json_dumps_pp(req, 4); printf("oauth get:\n%s\n", j); } int status = 404; xs_dict *msg = xs_dict_get(req, "q_vars"); xs *cmd = xs_replace(q_path, "/oauth", ""); srv_debug(0, xs_fmt("oauth_get_handler %s", q_path)); if (strcmp(cmd, "/authorize") == 0) { const char *cid = xs_dict_get(msg, "client_id"); const char *ruri = xs_dict_get(msg, "redirect_uri"); const char *rtype = xs_dict_get(msg, "response_type"); status = 400; if (cid && ruri && rtype && strcmp(rtype, "code") == 0) { xs *app = app_get(cid); if (app != NULL) { const char *host = xs_dict_get(srv_config, "host"); *body = xs_fmt(login_page, host, "", host, ruri, cid, USER_AGENT); *ctype = "text/html"; status = 200; srv_debug(0, xs_fmt("oauth authorize: generating login page")); } else srv_debug(0, xs_fmt("oauth authorize: bad client_id %s", cid)); } else srv_debug(0, xs_fmt("oauth authorize: invalid or unset arguments")); } return status; } int oauth_post_handler(const xs_dict *req, const char *q_path, const char *payload, int p_size, char **body, int *b_size, char **ctype) { if (!xs_startswith(q_path, "/oauth/")) return 0; { xs *j = xs_json_dumps_pp(req, 4); printf("oauth post:\n%s\n", j); } int status = 404; xs_dict *msg = xs_dict_get(req, "p_vars"); xs *cmd = xs_replace(q_path, "/oauth", ""); srv_debug(0, xs_fmt("oauth_post_handler %s", q_path)); if (strcmp(cmd, "/x-snac-login") == 0) { const char *login = xs_dict_get(msg, "login"); const char *passwd = xs_dict_get(msg, "passwd"); const char *redir = xs_dict_get(msg, "redir"); const char *cid = xs_dict_get(msg, "cid"); const char *host = xs_dict_get(srv_config, "host"); /* by default, generate another login form with an error */ *body = xs_fmt(login_page, host, "LOGIN INCORRECT", host, redir, cid, USER_AGENT); *ctype = "text/html"; status = 200; if (login && passwd && redir && cid) { snac snac; if (user_open(&snac, login)) { /* check the login + password */ if (check_password(login, passwd, xs_dict_get(snac.config, "passwd"))) { /* success! redirect to the desired uri */ xs *code = random_str(); xs_free(*body); *body = xs_fmt("%s?code=%s", redir, code); status = 303; srv_debug(0, xs_fmt("oauth x-snac-login: success, redirect to %s", *body)); /* assign the login to the app */ xs *app = app_get(cid); if (app != NULL) { app = xs_dict_set(app, "uid", login); app = xs_dict_set(app, "code", code); app_add(cid, app); } else srv_log(xs_fmt("oauth x-snac-login: error getting app %s", cid)); } else srv_debug(0, xs_fmt("oauth x-snac-login: login '%s' incorrect", login)); user_free(&snac); } else srv_debug(0, xs_fmt("oauth x-snac-login: bad user '%s'", login)); } else srv_debug(0, xs_fmt("oauth x-snac-login: invalid or unset arguments")); } else if (strcmp(cmd, "/token") == 0) { const char *gtype = xs_dict_get(msg, "grant_type"); const char *code = xs_dict_get(msg, "code"); const char *cid = xs_dict_get(msg, "client_id"); const char *csec = xs_dict_get(msg, "client_secret"); const char *ruri = xs_dict_get(msg, "redirect_uri"); if (gtype && code && cid && csec && ruri) { xs *app = app_get(cid); if (app == NULL) { status = 401; srv_log(xs_fmt("oauth token: invalid app %s", cid)); } else if (strcmp(csec, xs_dict_get(app, "client_secret")) != 0) { status = 401; srv_log(xs_fmt("oauth token: invalid client_secret for app %s", cid)); } else { xs *rsp = xs_dict_new(); xs *cat = xs_number_new(time(NULL)); xs *tokid = random_str(); rsp = xs_dict_append(rsp, "access_token", tokid); rsp = xs_dict_append(rsp, "token_type", "Bearer"); rsp = xs_dict_append(rsp, "created_at", cat); *body = xs_json_dumps_pp(rsp, 4); *ctype = "application/json"; status = 200; const char *uid = xs_dict_get(app, "uid"); srv_debug(0, xs_fmt("oauth token: " "successful login for %s, new token %s", uid, tokid)); xs *token = xs_dict_new(); token = xs_dict_append(token, "token", tokid); token = xs_dict_append(token, "client_id", cid); token = xs_dict_append(token, "client_secret", csec); token = xs_dict_append(token, "uid", uid); token = xs_dict_append(token, "code", code); token_add(tokid, token); } } else { srv_debug(0, xs_fmt("oauth token: invalid or unset arguments")); status = 400; } } else if (strcmp(cmd, "/revoke") == 0) { const char *cid = xs_dict_get(msg, "client_id"); const char *csec = xs_dict_get(msg, "client_secret"); const char *tokid = xs_dict_get(msg, "token"); if (cid && csec && tokid) { xs *token = token_get(tokid); *body = xs_str_new("{}"); *ctype = "application/json"; if (token == NULL || strcmp(csec, xs_dict_get(token, "client_secret")) != 0) { srv_debug(0, xs_fmt("oauth revoke: bad secret for token %s", tokid)); status = 403; } else { token_del(tokid); srv_debug(0, xs_fmt("oauth revoke: revoked token %s", tokid)); status = 200; /* also delete the app, as it serves no purpose from now on */ app_del(cid); } } else { srv_debug(0, xs_fmt("oauth revoke: invalid or unset arguments")); status = 403; } } return status; } xs_str *mastoapi_id(const xs_dict *msg) /* returns a somewhat Mastodon-compatible status id */ { char tmp[256] = ""; int n = 0; const char *id = xs_dict_get(msg, "id"); const char *published = xs_dict_get(msg, "published"); if (!xs_is_null(published)) { /* transfer all numbers from the published date */ while (*published && n < sizeof(tmp) - 1) { if (*published >= '0' && *published <= '9') tmp[n++] = *published; published++; } tmp[n] = '\0'; } xs *md5 = xs_md5_hex(id, strlen(id)); return xs_str_cat(xs_str_new(tmp), md5); } int mastoapi_get_handler(const xs_dict *req, const char *q_path, char **body, int *b_size, char **ctype) { if (!xs_startswith(q_path, "/api/v1/")) return 0; srv_debug(0, xs_fmt("mastoapi_get_handler %s", q_path)); { xs *j = xs_json_dumps_pp(req, 4); printf("mastoapi get:\n%s\n", j); } int status = 404; xs_dict *args = xs_dict_get(req, "q_vars"); xs *cmd = xs_replace(q_path, "/api/v1", ""); char *v; snac snac = {0}; int logged_in = 0; /* if there is an authorization field, try to validate it */ if (!xs_is_null(v = xs_dict_get(req, "authorization")) && xs_startswith(v, "Bearer ")) { xs *tokid = xs_replace(v, "Bearer ", ""); xs *token = token_get(tokid); if (token != NULL) { const char *uid = xs_dict_get(token, "uid"); if (!xs_is_null(uid) && user_open(&snac, uid)) { logged_in = 1; srv_debug(0, xs_fmt("mastoapi auth: valid token for user %s", uid)); } else srv_log(xs_fmt("mastoapi auth: corrupted token %s", tokid)); } else srv_log(xs_fmt("mastoapi auth: invalid token %s", tokid)); } if (strcmp(cmd, "/accounts/verify_credentials") == 0) { if (logged_in) { xs *acct = xs_dict_new(); acct = xs_dict_append(acct, "id", xs_dict_get(snac.config, "uid")); acct = xs_dict_append(acct, "username", xs_dict_get(snac.config, "uid")); acct = xs_dict_append(acct, "acct", xs_dict_get(snac.config, "uid")); acct = xs_dict_append(acct, "display_name", xs_dict_get(snac.config, "name")); acct = xs_dict_append(acct, "created_at", xs_dict_get(snac.config, "published")); acct = xs_dict_append(acct, "note", xs_dict_get(snac.config, "bio")); acct = xs_dict_append(acct, "url", snac.actor); xs *avatar = NULL; char *av = xs_dict_get(snac.config, "avatar"); if (xs_is_null(av) || *av == '\0') avatar = xs_fmt("%s/susie.png", srv_baseurl); else avatar = xs_dup(av); acct = xs_dict_append(acct, "avatar", avatar); *body = xs_json_dumps_pp(acct, 4); *ctype = "application/json"; status = 200; } else { status = 422; // "Unprocessable entity" (no login) } } else if (strcmp(cmd, "/timelines/home") == 0) { /* the private timeline */ if (logged_in) { const char *max_id = xs_dict_get(args, "max_id"); const char *since_id = xs_dict_get(args, "since_id"); const char *min_id = xs_dict_get(args, "min_id"); const char *limit_s = xs_dict_get(args, "limit"); int limit = 0; int cnt = 0; if (!xs_is_null(limit_s)) limit = atoi(limit_s); if (limit == 0) limit = 20; xs *timeline = timeline_simple_list(&snac, "private", 0, XS_ALL); xs *out = xs_list_new(); xs_list *p = timeline; xs_str *v; while (xs_list_iter(&p, &v) && cnt < limit) { xs *msg = NULL; /* only return entries older that max_id */ if (max_id) { if (strcmp(v, max_id) == 0) max_id = NULL; continue; } /* only returns entries newer than since_id */ if (since_id) { if (strcmp(v, since_id) == 0) break; } /* only returns entries newer than min_id */ /* what does really "Return results immediately newer than ID" mean? */ if (min_id) { if (strcmp(v, min_id) == 0) break; } /* get the entry */ if (!valid_status(timeline_get_by_md5(&snac, v, &msg))) continue; /* discard non-Notes */ if (strcmp(xs_dict_get(msg, "type"), "Note") != 0) continue; xs *actor = NULL; actor_get(&snac, xs_dict_get(msg, "attributedTo"), &actor); /* if the author is not here, discard */ if (actor == NULL) continue; /** shave the yak converting an ActivityPub Note to a Mastodon status **/ xs *acct = xs_dict_new(); const char *display_name = xs_dict_get(actor, "name"); if (xs_is_null(display_name) || *display_name == '\0') display_name = xs_dict_get(actor, "preferredUsername"); const char *id = xs_dict_get(actor, "id"); const char *pub = xs_dict_get(actor, "published"); xs *acct_md5 = xs_md5_hex(id, strlen(id)); acct = xs_dict_append(acct, "id", acct_md5); acct = xs_dict_append(acct, "username", xs_dict_get(actor, "preferredUsername")); acct = xs_dict_append(acct, "acct", xs_dict_get(actor, "preferredUsername")); acct = xs_dict_append(acct, "display_name", display_name); if (pub) acct = xs_dict_append(acct, "created_at", pub); acct = xs_dict_append(acct, "note", xs_dict_get(actor, "summary")); acct = xs_dict_append(acct, "url", id); xs *avatar = NULL; xs_dict *av = xs_dict_get(actor, "icon"); if (xs_type(av) == XSTYPE_DICT) avatar = xs_dup(xs_dict_get(av, "url")); else avatar = xs_fmt("%s/susie.png", srv_baseurl); acct = xs_dict_append(acct, "avatar", avatar); xs *f = xs_val_new(XSTYPE_FALSE); xs *t = xs_val_new(XSTYPE_TRUE); xs *n = xs_val_new(XSTYPE_NULL); xs *el = xs_list_new(); xs *idx = NULL; xs *ixc = NULL; char *tmp; id = xs_dict_get(msg, "id"); xs *mid = mastoapi_id(msg); xs *st = xs_dict_new(); st = xs_dict_append(st, "id", mid); st = xs_dict_append(st, "uri", id); st = xs_dict_append(st, "url", id); st = xs_dict_append(st, "created_at", xs_dict_get(msg, "published")); st = xs_dict_append(st, "account", acct); st = xs_dict_append(st, "content", xs_dict_get(msg, "content")); st = xs_dict_append(st, "visibility", is_msg_public(&snac, msg) ? "public" : "private"); tmp = xs_dict_get(msg, "sensitive"); if (xs_is_null(tmp)) tmp = f; st = xs_dict_append(st, "sensitive", tmp); tmp = xs_dict_get(msg, "summary"); if (xs_is_null(tmp)) tmp = ""; st = xs_dict_append(st, "spoiler_text", tmp); st = xs_dict_append(st, "media_attachments", el); st = xs_dict_append(st, "mentions", el); st = xs_dict_append(st, "tags", el); st = xs_dict_append(st, "emojis", el); xs_free(idx); xs_free(ixc); idx = object_likes(id); ixc = xs_number_new(xs_list_len(idx)); st = xs_dict_append(st, "favourites_count", ixc); st = xs_dict_append(st, "favourited", xs_list_in(idx, snac.md5) != -1 ? t : f); xs_free(idx); xs_free(ixc); idx = object_announces(id); ixc = xs_number_new(xs_list_len(idx)); st = xs_dict_append(st, "reblogs_count", ixc); st = xs_dict_append(st, "reblogged", xs_list_in(idx, snac.md5) != -1 ? t : f); xs_free(idx); xs_free(ixc); idx = object_children(id); ixc = xs_number_new(xs_list_len(idx)); st = xs_dict_append(st, "replies_count", ixc); /* default in_reply_to values */ st = xs_dict_append(st, "in_reply_to_id", n); st = xs_dict_append(st, "in_reply_to_account_id", n); tmp = xs_dict_get(msg, "inReplyTo"); if (!xs_is_null(tmp)) { xs *irto = NULL; if (valid_status(object_get(tmp, &irto))) { xs *irt_mid = mastoapi_id(irto); st = xs_dict_set(st, "in_reply_to_id", irt_mid); char *at = NULL; if (!xs_is_null(at = xs_dict_get(irto, "attributedTo"))) { xs *at_md5 = xs_md5_hex(at, strlen(at)); st = xs_dict_set(st, "in_reply_to_account_id", at_md5); } } } st = xs_dict_append(st, "reblog", n); st = xs_dict_append(st, "poll", n); st = xs_dict_append(st, "card", n); st = xs_dict_append(st, "language", n); tmp = xs_dict_get(msg, "sourceContent"); if (xs_is_null(tmp)) tmp = ""; st = xs_dict_append(st, "text", tmp); tmp = xs_dict_get(msg, "updated"); if (xs_is_null(tmp)) tmp = n; st = xs_dict_append(st, "edited_at", tmp); out = xs_list_append(out, st); cnt++; } *body = xs_json_dumps_pp(out, 4); *ctype = "application/json"; status = 200; srv_debug(0, xs_fmt("mastoapi timeline: returned %d entries", xs_list_len(out))); } else { status = 401; // unauthorized } } else if (strcmp(cmd, "/timelines/public") == 0) { /* the public timeline */ } /* user cleanup */ if (logged_in) user_free(&snac); return status; } int mastoapi_post_handler(const xs_dict *req, const char *q_path, const char *payload, int p_size, char **body, int *b_size, char **ctype) { if (!xs_startswith(q_path, "/api/v1/")) return 0; srv_debug(0, xs_fmt("mastoapi_post_handler %s", q_path)); { xs *j = xs_json_dumps_pp(req, 4); printf("mastoapi post:\n%s\n", j); } int status = 404; xs *msg = NULL; char *i_ctype = xs_dict_get(req, "content-type"); if (xs_startswith(i_ctype, "application/json")) msg = xs_json_loads(payload); else msg = xs_dup(xs_dict_get(req, "p_vars")); if (msg == NULL) return 400; { xs *j = xs_json_dumps_pp(msg, 4); printf("%s\n", j); } xs *cmd = xs_replace(q_path, "/api/v1", ""); if (strcmp(cmd, "/apps") == 0) { const char *name = xs_dict_get(msg, "client_name"); const char *ruri = xs_dict_get(msg, "redirect_uris"); const char *scope = xs_dict_get(msg, "scope"); if (xs_type(ruri) == XSTYPE_LIST) ruri = xs_dict_get(ruri, 0); if (name && ruri) { xs *app = xs_dict_new(); xs *id = xs_replace_i(tid(0), ".", ""); xs *cid = random_str(); xs *csec = random_str(); xs *vkey = random_str(); app = xs_dict_append(app, "name", name); app = xs_dict_append(app, "redirect_uri", ruri); app = xs_dict_append(app, "client_id", cid); app = xs_dict_append(app, "client_secret", csec); app = xs_dict_append(app, "vapid_key", vkey); app = xs_dict_append(app, "id", id); *body = xs_json_dumps_pp(app, 4); *ctype = "application/json"; status = 200; app = xs_dict_append(app, "code", ""); if (scope) app = xs_dict_append(app, "scope", scope); app_add(cid, app); srv_debug(0, xs_fmt("mastoapi apps: new app %s", cid)); } } return status; }