snac2/activitypub.c
default d35c949a13 Resolve (partially) the issue with mentions without server.
Mastodon (mainly from the API) usually include mentions without server,
which is just stupid. This patch tries to resolve these broken mentions in
process_tags() by looking for a user name starting with it in the already
pre-populated tag list. As of now, this only works if the message is an
inReplyTo and the broken mention is the one of the original
(attributedTo) poster.
2023-05-12 11:56:17 +02:00

1674 lines
48 KiB
C

/* snac - A simple, minimalistic ActivityPub instance */
/* copyright (c) 2022 - 2023 grunfink / MIT license */
#include "xs.h"
#include "xs_encdec.h"
#include "xs_json.h"
#include "xs_curl.h"
#include "xs_mime.h"
#include "xs_openssl.h"
#include "xs_regex.h"
#include "xs_time.h"
#include "xs_set.h"
#include "snac.h"
#include <sys/wait.h>
const char *public_address = "https:/" "/www.w3.org/ns/activitystreams#Public";
/* susie.png */
const char *susie =
"iVBORw0KGgoAAAANSUhEUgAAAEAAAABAAQAAAAC"
"CEkxzAAAAUUlEQVQoz43R0QkAMQwCUDdw/y3dwE"
"vsvzlL4X1IoQkAisKmwfAFT3RgJHbQezpSRoXEq"
"eqCL9BJBf7h3QbOCCxV5EVWMEMwG7K1/WODtlvx"
"AYTtEsDU9F34AAAAAElFTkSuQmCC";
const char *susie_cool =
"iVBORw0KGgoAAAANSUhEUgAAAEAAAABAAQAAAAC"
"CEkxzAAAAV0lEQVQoz43RwQ3AMAwCQDZg/y3ZgN"
"qo3+JaedwDOUQBQFHYaTB8wTM6sGl2cMPu+DFzn"
"+ZcgN7wF7ZVihXkfSlWIVzIA6dbQzaygllpNuTX"
"ZmmFNlvxADX1+o0cUPMbAAAAAElFTkSuQmCC";
const char *default_avatar_base64(void)
/* returns the default avatar in base64 */
{
time_t t = time(NULL);
struct tm tm;
gmtime_r(&t, &tm);
return tm.tm_wday == 0 || tm.tm_wday == 6 ? susie_cool : susie;
}
int activitypub_request(snac *snac, const char *url, xs_dict **data)
/* request an object */
{
int status;
xs *response = NULL;
xs *payload = NULL;
int p_size;
char *ctype;
/* get from the net */
response = http_signed_request(snac, "GET", url,
NULL, NULL, 0, &status, &payload, &p_size, 0);
if (status == 0 || (status >= 500 && status <= 599)) {
/* I found an instance running Misskey that returned
500 on signed messages but returned the object
perfectly without signing (?), so why not try */
xs_free(response);
xs *hdrs = xs_dict_new();
hdrs = xs_dict_append(hdrs, "accept", "application/activity+json");
hdrs = xs_dict_append(hdrs, "user-agent", USER_AGENT);
response = xs_http_request("GET", url, hdrs,
NULL, 0, &status, &payload, &p_size, 0);
}
if (valid_status(status)) {
/* ensure it's ActivityPub data */
ctype = xs_dict_get(response, "content-type");
if (xs_str_in(ctype, "application/activity+json") != -1 ||
xs_str_in(ctype, "application/ld+json") != -1)
*data = xs_json_loads(payload);
else
status = 500;
}
if (!valid_status(status))
*data = NULL;
return status;
}
int actor_request(snac *snac, const char *actor, xs_dict **data)
/* request an actor */
{
int status, status2;
xs *payload = NULL;
if (data)
*data = NULL;
/* get from disk first */
status = actor_get(snac, actor, data);
if (status != 200) {
/* actor data non-existent or stale: get from the net */
status2 = activitypub_request(snac, actor, &payload);
if (valid_status(status2)) {
/* renew data */
status = actor_add(actor, payload);
if (data != NULL) {
*data = payload;
payload = NULL;
}
}
}
/* collect the (presumed) shared inbox in this actor */
if (xs_type(xs_dict_get(srv_config, "disable_inbox_collection")) != XSTYPE_TRUE) {
if (valid_status(status) && data && *data)
inbox_add_by_actor(*data);
}
else
srv_log(xs_fmt("NOT collected"));
return status;
}
int timeline_request(snac *snac, char **id, d_char **wrk)
/* ensures that an entry and its ancestors are in the timeline */
{
int status = 0;
if (!xs_is_null(*id)) {
/* is the admired object already there? */
if (!object_here(*id)) {
xs *object = NULL;
/* no; download it */
status = activitypub_request(snac, *id, &object);
if (valid_status(status)) {
char *type = xs_dict_get(object, "type");
/* get the id again from the object, as it may be different */
char *nid = xs_dict_get(object, "id");
if (wrk && strcmp(nid, *id) != 0) {
snac_debug(snac, 1,
xs_fmt("timeline_request canonical id for %s is %s", *id, nid));
*wrk = xs_dup(nid);
*id = *wrk;
}
if (!xs_is_null(type) && strcmp(type, "Note") == 0) {
char *actor = xs_dict_get(object, "attributedTo");
/* request (and drop) the actor for this entry */
if (!xs_is_null(actor))
actor_request(snac, actor, NULL);
/* does it have an ancestor? */
char *in_reply_to = xs_dict_get(object, "inReplyTo");
/* recurse! */
timeline_request(snac, &in_reply_to, NULL);
/* finally store */
timeline_add(snac, *id, object);
}
}
}
}
return status;
}
int send_to_inbox_raw(const char *keyid, const char *seckey,
const xs_str *inbox, const xs_dict *msg,
xs_val **payload, int *p_size, int timeout)
/* sends a message to an Inbox */
{
int status;
xs_dict *response;
xs *j_msg = xs_json_dumps_pp((xs_dict *)msg, 4);
response = http_signed_request_raw(keyid, seckey, "POST", inbox,
NULL, j_msg, strlen(j_msg), &status, payload, p_size, timeout);
xs_free(response);
return status;
}
int send_to_inbox(snac *snac, const xs_str *inbox, const xs_dict *msg,
xs_val **payload, int *p_size, int timeout)
/* sends a message to an Inbox */
{
char *seckey = xs_dict_get(snac->key, "secret");
return send_to_inbox_raw(snac->actor, seckey, inbox, msg, payload, p_size, timeout);
}
d_char *get_actor_inbox(snac *snac, const char *actor)
/* gets an actor's inbox */
{
xs *data = NULL;
char *v = NULL;
if (valid_status(actor_request(snac, actor, &data))) {
/* try first endpoints/sharedInbox */
if ((v = xs_dict_get(data, "endpoints")))
v = xs_dict_get(v, "sharedInbox");
/* try then the regular inbox */
if (xs_is_null(v))
v = xs_dict_get(data, "inbox");
}
return xs_is_null(v) ? NULL : xs_dup(v);
}
int send_to_actor(snac *snac, char *actor, char *msg, d_char **payload, int *p_size, int timeout)
/* sends a message to an actor */
{
int status = 400;
xs *inbox = get_actor_inbox(snac, actor);
if (!xs_is_null(inbox))
status = send_to_inbox(snac, inbox, msg, payload, p_size, timeout);
return status;
}
xs_list *recipient_list(snac *snac, const xs_dict *msg, int expand_public)
/* returns the list of recipients for a message */
{
char *to = xs_dict_get(msg, "to");
char *cc = xs_dict_get(msg, "cc");
xs_set rcpts;
int n;
xs_set_init(&rcpts);
char *lists[] = { to, cc, NULL };
for (n = 0; lists[n]; n++) {
char *l = lists[n];
char *v;
xs *tl = NULL;
/* if it's a string, create a list with only one element */
if (xs_type(l) == XSTYPE_STRING) {
tl = xs_list_new();
tl = xs_list_append(tl, l);
l = tl;
}
while (xs_list_iter(&l, &v)) {
if (expand_public && strcmp(v, public_address) == 0) {
/* iterate the followers and add them */
xs *fwers = follower_list(snac);
char *actor;
char *p = fwers;
while (xs_list_iter(&p, &actor))
xs_set_add(&rcpts, actor);
}
else
xs_set_add(&rcpts, v);
}
}
return xs_set_result(&rcpts);
}
int is_msg_public(snac *snac, const xs_dict *msg)
/* checks if a message is public */
{
xs *rcpts = recipient_list(snac, msg, 0);
return xs_list_in(rcpts, public_address) != -1;
}
int is_msg_for_me(snac *snac, const xs_dict *c_msg)
/* checks if this message is for me */
{
const char *type = xs_dict_get(c_msg, "type");
if (strcmp(type, "Announce") == 0) {
const char *object = xs_dict_get(c_msg, "object");
if (xs_type(object) == XSTYPE_DICT)
object = xs_dict_get(object, "id");
/* if it's about one of our posts, accept it */
if (xs_startswith(object, snac->actor))
return 2;
/* if it's by someone we don't follow, reject */
if (!following_check(snac, xs_dict_get(c_msg, "actor")))
return 0;
}
/* if it's not a Create, allow */
if (strcmp(type, "Create") != 0)
return 1;
xs_dict *msg = xs_dict_get(c_msg, "object");
xs *rcpts = recipient_list(snac, msg, 0);
xs_list *p = rcpts;
xs_str *v;
while(xs_list_iter(&p, &v)) {
/* explicitly for me? accept */
if (strcmp(v, snac->actor) == 0)
return 2;
/* for someone we follow? (probably cc'ed) accept */
if (following_check(snac, v))
return 5;
}
/* accept if it's by someone we follow */
char *atto = xs_dict_get(msg, "attributedTo");
if (!xs_is_null(atto) && following_check(snac, atto))
return 3;
/* is this message a reply to another? */
char *irt = xs_dict_get(msg, "inReplyTo");
if (!xs_is_null(irt)) {
xs *r_msg = NULL;
/* try to get the replied message */
if (valid_status(object_get(irt, &r_msg))) {
atto = xs_dict_get(r_msg, "attributedTo");
/* accept if the replied message is from someone we follow */
if (!xs_is_null(atto) && following_check(snac, atto))
return 4;
}
}
return 0;
}
void process_tags(snac *snac, const char *content, xs_str **n_content, xs_list **tag)
/* parses mentions and tags from content */
{
xs_str *nc = xs_str_new(NULL);
xs_list *tl = *tag;
xs *split;
xs_list *p;
xs_val *v;
int n = 0;
split = xs_regex_split(content, "(@[A-Za-z0-9_]+(@[A-Za-z0-9\\.-]+)?|&#[0-9]+;|#[^ ,\\.:;<]+)");
p = split;
while (xs_list_iter(&p, &v)) {
if ((n & 0x1)) {
if (*v == '@') {
xs *link = NULL;
if (strchr(v + 1, '@') == NULL) {
/* only one @? it's a dumb Mastodon-like mention
without server; check if there is anybody
whose name starts with this in the tag list */
xs_list *p2 = tl;
xs_dict *v2;
xs *pname = xs_fmt("%s@", v);
while (xs_list_iter(&p2, &v2)) {
const char *type = xs_dict_get(v2, "type");
if (type && strcmp(type, "Mention") == 0) {
const char *name = xs_dict_get(v2, "name");
const char *href = xs_dict_get(v2, "href");
if (name && href && (xs_startswith(name, pname) ||
xs_startswith(name, pname + 1))) {
/* good enough :shrug2: */
link = xs_fmt(
"<a href=\"%s\" class=\"u-url mention\">%s</a>", href, name);
break;
}
}
}
snac_debug(snac, 2, xs_fmt(
"mention without server '%s' (%s)", v, link ? link : "none"));
}
else {
/* query the webfinger about this fellow */
xs *v2 = xs_strip_chars_i(xs_dup(v), "@.");
xs *actor = NULL;
xs *uid = NULL;
int status;
status = webfinger_request(v2, &actor, &uid);
if (valid_status(status)) {
xs *d = xs_dict_new();
xs *n = xs_fmt("@%s", uid);
d = xs_dict_append(d, "type", "Mention");
d = xs_dict_append(d, "href", actor);
d = xs_dict_append(d, "name", n);
tl = xs_list_append(tl, d);
link = xs_fmt("<a href=\"%s\" class=\"u-url mention\">%s</a>", actor, n);
}
}
if (!xs_is_null(link))
nc = xs_str_cat(nc, link);
else
nc = xs_str_cat(nc, v);
}
else
if (*v == '#') {
/* hashtag */
xs *d = xs_dict_new();
xs *n = xs_tolower_i(xs_dup(v));
xs *h = xs_fmt("%s%s", snac->actor, n);
xs *l = xs_fmt("<a href=\"%s\" class=\"mention hashtag\" rel=\"tag\">%s</a>", h, v);
d = xs_dict_append(d, "type", "Hashtag");
d = xs_dict_append(d, "href", h);
d = xs_dict_append(d, "name", n);
tl = xs_list_append(tl, d);
/* add the code */
nc = xs_str_cat(nc, l);
}
else
if (*v == '&') {
/* HTML Unicode entity, probably part of an emoji */
/* write as is */
nc = xs_str_cat(nc, v);
}
}
else
nc = xs_str_cat(nc, v);
n++;
}
*n_content = nc;
*tag = tl;
}
/** messages **/
xs_dict *msg_base(snac *snac, const char *type, const char *id,
const char *actor, const char *date, const char *object)
/* creates a base ActivityPub message */
{
xs *did = NULL;
xs *published = NULL;
xs *ntid = tid(0);
/* generated values */
if (date && strcmp(date, "@now") == 0) {
published = xs_str_utctime(0, "%Y-%m-%dT%H:%M:%SZ");
date = published;
}
if (id != NULL) {
if (strcmp(id, "@dummy") == 0) {
did = xs_fmt("%s/d/%s/%s", snac->actor, ntid, type);
id = did;
}
else
if (strcmp(id, "@object") == 0) {
if (object != NULL) {
did = xs_fmt("%s/%s_%s", xs_dict_get(object, "id"), type, ntid);
id = did;
}
else
id = NULL;
}
}
xs_dict *msg = xs_dict_new();
msg = xs_dict_append(msg, "@context", "https:/" "/www.w3.org/ns/activitystreams");
msg = xs_dict_append(msg, "type", type);
if (id != NULL)
msg = xs_dict_append(msg, "id", id);
if (actor != NULL)
msg = xs_dict_append(msg, "actor", actor);
if (date != NULL)
msg = xs_dict_append(msg, "published", date);
if (object != NULL)
msg = xs_dict_append(msg, "object", object);
return msg;
}
d_char *msg_collection(snac *snac, char *id)
/* creates an empty OrderedCollection message */
{
d_char *msg = msg_base(snac, "OrderedCollection", id, NULL, NULL, NULL);
xs *ol = xs_list_new();
xs *nz = xs_number_new(0);
msg = xs_dict_append(msg, "attributedTo", snac->actor);
msg = xs_dict_append(msg, "orderedItems", ol);
msg = xs_dict_append(msg, "totalItems", nz);
return msg;
}
d_char *msg_accept(snac *snac, char *object, char *to)
/* creates an Accept message (as a response to a Follow) */
{
d_char *msg = msg_base(snac, "Accept", "@dummy", snac->actor, NULL, object);
msg = xs_dict_append(msg, "to", to);
return msg;
}
xs_dict *msg_update(snac *snac, xs_dict *object)
/* creates an Update message */
{
d_char *msg = msg_base(snac, "Update", "@object", snac->actor, "@now", object);
char *type = xs_dict_get(object, "type");
if (strcmp(type, "Note") == 0) {
msg = xs_dict_append(msg, "to", xs_dict_get(object, "to"));
msg = xs_dict_append(msg, "cc", xs_dict_get(object, "cc"));
}
else
msg = xs_dict_append(msg, "to", public_address);
return msg;
}
d_char *msg_admiration(snac *snac, char *object, char *type)
/* creates a Like or Announce message */
{
xs *a_msg = NULL;
d_char *msg = NULL;
xs *wrk = NULL;
/* call the object */
timeline_request(snac, &object, &wrk);
if (valid_status(object_get(object, &a_msg))) {
xs *rcpts = xs_list_new();
msg = msg_base(snac, type, "@dummy", snac->actor, "@now", object);
if (is_msg_public(snac, a_msg))
rcpts = xs_list_append(rcpts, public_address);
rcpts = xs_list_append(rcpts, xs_dict_get(a_msg, "attributedTo"));
msg = xs_dict_append(msg, "to", rcpts);
}
else
snac_log(snac, xs_fmt("msg_admiration cannot retrieve object %s", object));
return msg;
}
d_char *msg_actor(snac *snac)
/* create a Person message for this actor */
{
xs *ctxt = xs_list_new();
xs *icon = xs_dict_new();
xs *keys = xs_dict_new();
xs *avtr = NULL;
xs *kid = NULL;
xs *f_bio = NULL;
d_char *msg = msg_base(snac, "Person", snac->actor, NULL, NULL, NULL);
char *p;
int n;
/* change the @context (is this really necessary?) */
ctxt = xs_list_append(ctxt, "https:/" "/www.w3.org/ns/activitystreams");
ctxt = xs_list_append(ctxt, "https:/" "/w3id.org/security/v1");
msg = xs_dict_set(msg, "@context", ctxt);
msg = xs_dict_set(msg, "url", snac->actor);
msg = xs_dict_set(msg, "name", xs_dict_get(snac->config, "name"));
msg = xs_dict_set(msg, "preferredUsername", snac->uid);
msg = xs_dict_set(msg, "published", xs_dict_get(snac->config, "published"));
f_bio = not_really_markdown(xs_dict_get(snac->config, "bio"));
msg = xs_dict_set(msg, "summary", f_bio);
char *folders[] = { "inbox", "outbox", "followers", "following", NULL };
for (n = 0; folders[n]; n++) {
xs *f = xs_fmt("%s/%s", snac->actor, folders[n]);
msg = xs_dict_set(msg, folders[n], f);
}
p = xs_dict_get(snac->config, "avatar");
if (*p == '\0')
avtr = xs_fmt("%s/susie.png", srv_baseurl);
else
avtr = xs_dup(p);
icon = xs_dict_append(icon, "type", "Image");
icon = xs_dict_append(icon, "mediaType", xs_mime_by_ext(avtr));
icon = xs_dict_append(icon, "url", avtr);
msg = xs_dict_set(msg, "icon", icon);
kid = xs_fmt("%s#main-key", snac->actor);
keys = xs_dict_append(keys, "id", kid);
keys = xs_dict_append(keys, "owner", snac->actor);
keys = xs_dict_append(keys, "publicKeyPem", xs_dict_get(snac->key, "public"));
msg = xs_dict_set(msg, "publicKey", keys);
return msg;
}
d_char *msg_create(snac *snac, char *object)
/* creates a 'Create' message */
{
d_char *msg = msg_base(snac, "Create", "@object", snac->actor, "@now", object);
msg = xs_dict_append(msg, "attributedTo", xs_dict_get(object, "attributedTo"));
msg = xs_dict_append(msg, "to", xs_dict_get(object, "to"));
msg = xs_dict_append(msg, "cc", xs_dict_get(object, "cc"));
return msg;
}
d_char *msg_undo(snac *snac, char *object)
/* creates an 'Undo' message */
{
d_char *msg = msg_base(snac, "Undo", "@object", snac->actor, "@now", object);
msg = xs_dict_append(msg, "to", xs_dict_get(object, "object"));
return msg;
}
d_char *msg_delete(snac *snac, char *id)
/* creates a 'Delete' + 'Tombstone' for a local entry */
{
xs *tomb = xs_dict_new();
d_char *msg = NULL;
/* sculpt the tombstone */
tomb = xs_dict_append(tomb, "type", "Tombstone");
tomb = xs_dict_append(tomb, "id", id);
/* now create the Delete */
msg = msg_base(snac, "Delete", "@object", snac->actor, "@now", tomb);
msg = xs_dict_append(msg, "to", public_address);
return msg;
}
xs_dict *msg_follow(snac *snac, const char *q)
/* creates a 'Follow' message */
{
xs *actor_o = NULL;
xs *actor = NULL;
d_char *msg = NULL;
int status;
xs *url_or_uid = xs_strip_i(xs_str_new(q));
if (xs_startswith(url_or_uid, "https:/"))
actor = xs_dup(url_or_uid);
else
if (!valid_status(webfinger_request(url_or_uid, &actor, NULL)) || actor == NULL) {
snac_log(snac, xs_fmt("cannot resolve user %s to follow", url_or_uid));
return NULL;
}
/* request the actor */
status = actor_request(snac, actor, &actor_o);
if (valid_status(status)) {
/* check if the actor is an alias */
char *r_actor = xs_dict_get(actor_o, "id");
if (r_actor && strcmp(actor, r_actor) != 0) {
snac_log(snac, xs_fmt("actor to follow is an alias %s -> %s", actor, r_actor));
}
msg = msg_base(snac, "Follow", "@dummy", snac->actor, NULL, r_actor);
}
else
snac_log(snac, xs_fmt("cannot get actor to follow %s %d", actor, status));
return msg;
}
xs_dict *msg_note(snac *snac, const xs_str *content, const xs_val *rcpts,
xs_str *in_reply_to, xs_list *attach, int priv)
/* creates a 'Note' message */
{
xs *ntid = tid(0);
xs *id = xs_fmt("%s/p/%s", snac->actor, ntid);
xs *ctxt = NULL;
xs *fc2 = NULL;
xs *fc1 = NULL;
xs *to = NULL;
xs *cc = xs_list_new();
xs *irt = NULL;
xs *tag = xs_list_new();
xs *atls = NULL;
xs_dict *msg = msg_base(snac, "Note", id, NULL, "@now", NULL);
xs_list *p;
xs_val *v;
if (rcpts == NULL)
to = xs_list_new();
else {
if (xs_type(rcpts) == XSTYPE_STRING) {
to = xs_list_new();
to = xs_list_append(to, rcpts);
}
else
to = xs_dup(rcpts);
}
/* format the content */
fc2 = not_really_markdown(content);
if (in_reply_to != NULL && *in_reply_to) {
xs *p_msg = NULL;
xs *wrk = NULL;
/* demand this thing */
timeline_request(snac, &in_reply_to, &wrk);
if (valid_status(object_get(in_reply_to, &p_msg))) {
/* add this author as recipient */
char *a, *v;
if ((a = xs_dict_get(p_msg, "attributedTo")) && xs_list_in(to, a) == -1)
to = xs_list_append(to, a);
/* add this author to the tag list as a mention */
xs *t_href = NULL;
xs *t_name = NULL;
if (!xs_is_null(a) && valid_status(webfinger_request(a, &t_href, &t_name))) {
xs *t = xs_dict_new();
t = xs_dict_append(t, "type", "Mention");
t = xs_dict_append(t, "href", t_href);
t = xs_dict_append(t, "name", t_name);
tag = xs_list_append(tag, t);
}
/* get the context, if there is one */
if ((v = xs_dict_get(p_msg, "context")))
ctxt = xs_dup(v);
/* if this message is public, ours will also be */
if (!priv && is_msg_public(snac, p_msg) && xs_list_in(to, public_address) == -1)
to = xs_list_append(to, public_address);
}
irt = xs_dup(in_reply_to);
}
else
irt = xs_val_new(XSTYPE_NULL);
/* extract the mentions and hashtags and convert the content */
process_tags(snac, fc2, &fc1, &tag);
/* create the attachment list, if there are any */
if (!xs_is_null(attach)) {
atls = xs_list_new();
while (xs_list_iter(&attach, &v)) {
xs *d = xs_dict_new();
char *url = xs_list_get(v, 0);
char *alt = xs_list_get(v, 1);
char *mime = xs_mime_by_ext(url);
d = xs_dict_append(d, "mediaType", mime);
d = xs_dict_append(d, "url", url);
d = xs_dict_append(d, "name", alt);
d = xs_dict_append(d, "type",
xs_startswith(mime, "image/") ? "Image" : "Document");
atls = xs_list_append(atls, d);
}
}
if (ctxt == NULL)
ctxt = xs_fmt("%s#ctxt", id);
/* add all mentions to the cc */
p = tag;
while (xs_list_iter(&p, &v)) {
if (xs_type(v) == XSTYPE_DICT) {
char *t;
if ((t = xs_dict_get(v, "type")) != NULL && strcmp(t, "Mention") == 0) {
if ((t = xs_dict_get(v, "href")) != NULL)
cc = xs_list_append(cc, t);
}
}
}
/* no recipients? must be for everybody */
if (!priv && xs_list_len(to) == 0)
to = xs_list_append(to, public_address);
/* delete all cc recipients that also are in the to */
p = to;
while (xs_list_iter(&p, &v)) {
int i;
if ((i = xs_list_in(cc, v)) != -1)
cc = xs_list_del(cc, i);
}
msg = xs_dict_append(msg, "attributedTo", snac->actor);
msg = xs_dict_append(msg, "summary", "");
msg = xs_dict_append(msg, "content", fc1);
msg = xs_dict_append(msg, "context", ctxt);
msg = xs_dict_append(msg, "url", id);
msg = xs_dict_append(msg, "to", to);
msg = xs_dict_append(msg, "cc", cc);
msg = xs_dict_append(msg, "inReplyTo", irt);
msg = xs_dict_append(msg, "tag", tag);
msg = xs_dict_append(msg, "sourceContent", content);
if (atls != NULL)
msg = xs_dict_append(msg, "attachment", atls);
return msg;
}
xs_dict *msg_ping(snac *user, const char *rcpt)
/* creates a Ping message (https://humungus.tedunangst.com/r/honk/v/tip/f/docs/ping.txt) */
{
xs_dict *msg = msg_base(user, "Ping", "@dummy", user->actor, NULL, NULL);
msg = xs_dict_append(msg, "to", rcpt);
return msg;
}
xs_dict *msg_pong(snac *user, const char *rcpt, const char *object)
/* creates a Pong message (https://humungus.tedunangst.com/r/honk/v/tip/f/docs/ping.txt) */
{
xs_dict *msg = msg_base(user, "Pong", "@dummy", user->actor, NULL, object);
msg = xs_dict_append(msg, "to", rcpt);
return msg;
}
void notify(snac *snac, xs_str *type, xs_str *utype, xs_str *actor, xs_dict *msg)
/* notifies the user of relevant events */
{
if (strcmp(type, "Create") == 0) {
/* only notify of notes specifically for us */
xs *rcpts = recipient_list(snac, msg, 0);
if (xs_list_in(rcpts, snac->actor) == -1)
return;
}
if (strcmp(type, "Undo") == 0 && strcmp(utype, "Follow") != 0)
return;
/* get the object id */
const char *objid = xs_dict_get(msg, "object");
if (xs_type(objid) == XSTYPE_DICT)
objid = xs_dict_get(objid, "id");
if (strcmp(type, "Like") == 0 || strcmp(type, "Announce") == 0) {
/* if it's not an admiration about something by us, done */
if (xs_is_null(objid) || !xs_startswith(objid, snac->actor))
return;
}
/* user will love to know about this! */
/* prepare message body */
xs *body = xs_fmt("User : @%s@%s\n",
xs_dict_get(snac->config, "uid"),
xs_dict_get(srv_config, "host")
);
if (strcmp(utype, "(null)") != 0) {
xs *s1 = xs_fmt("Type : %s + %s\n", type, utype);
body = xs_str_cat(body, s1);
}
else {
xs *s1 = xs_fmt("Type : %s\n", type);
body = xs_str_cat(body, s1);
}
{
xs *s1 = xs_fmt("Actor : %s\n", actor);
body = xs_str_cat(body, s1);
}
if (objid != NULL) {
xs *s1 = xs_fmt("Object: %s\n", objid);
body = xs_str_cat(body, s1);
}
/* email */
const char *email = "[disabled by admin]";
if (xs_type(xs_dict_get(srv_config, "disable_email_notifications")) != XSTYPE_TRUE) {
email = xs_dict_get(snac->config_o, "email");
if (xs_is_null(email)) {
email = xs_dict_get(snac->config, "email");
if (xs_is_null(email))
email = "[empty]";
}
}
if (*email != '\0' && *email != '[') {
snac_debug(snac, 1, xs_fmt("email notify %s %s %s", type, utype, actor));
xs *subject = xs_fmt("snac notify for @%s@%s",
xs_dict_get(snac->config, "uid"), xs_dict_get(srv_config, "host"));
xs *from = xs_fmt("snac-daemon <snac-daemon@%s>", xs_dict_get(srv_config, "host"));
xs *header = xs_fmt(
"From: %s\n"
"To: %s\n"
"Subject: %s\n"
"\n",
from, email, subject);
xs *email_body = xs_fmt("%s%s", header, body);
enqueue_email(email_body, 0);
}
/* telegram */
char *bot = xs_dict_get(snac->config, "telegram_bot");
char *chat_id = xs_dict_get(snac->config, "telegram_chat_id");
if (!xs_is_null(bot) && !xs_is_null(chat_id) && *bot && *chat_id)
enqueue_telegram(body, bot, chat_id);
/* finally, store it in the notification folder */
if (strcmp(type, "Follow") == 0)
objid = xs_dict_get(msg, "id");
notify_add(snac, type, utype, actor, objid);
}
/** queues **/
int process_input_message(snac *snac, xs_dict *msg, xs_dict *req)
/* processes an ActivityPub message from the input queue */
{
/* actor and type exist, were checked previously */
char *actor = xs_dict_get(msg, "actor");
char *type = xs_dict_get(msg, "type");
xs *actor_o = NULL;
int a_status;
int do_notify = 0;
if (xs_is_null(actor) || xs_is_null(type)) {
snac_debug(snac, 0, xs_fmt("malformed message"));
return 1;
}
char *object, *utype;
object = xs_dict_get(msg, "object");
if (object != NULL && xs_type(object) == XSTYPE_DICT)
utype = xs_dict_get(object, "type");
else
utype = "(null)";
/* reject messages that are not for this user */
if (!is_msg_for_me(snac, msg)) {
snac_debug(snac, 0, xs_fmt("message from %s of type '%s' not for us", actor, type));
return 1;
}
/* bring the actor */
a_status = actor_request(snac, actor, &actor_o);
/* if the actor does not explicitly exist, discard */
if (a_status == 404 || a_status == 410) {
snac_debug(snac, 1,
xs_fmt("dropping message due to actor error %s %d", actor, a_status));
return 1;
}
if (!valid_status(a_status)) {
/* other actor download errors may need a retry */
snac_debug(snac, 1,
xs_fmt("error requesting actor %s %d -- retry later", actor, a_status));
return 0;
}
/* check the signature */
xs *sig_err = NULL;
if (!check_signature(snac, req, &sig_err)) {
snac_log(snac, xs_fmt("bad signature %s (%s)", actor, sig_err));
srv_archive_error("check_signature", sig_err, req, msg);
return 1;
}
if (strcmp(type, "Follow") == 0) {
if (!follower_check(snac, actor)) {
xs *f_msg = xs_dup(msg);
xs *reply = msg_accept(snac, f_msg, actor);
enqueue_message(snac, reply);
if (xs_is_null(xs_dict_get(f_msg, "published"))) {
/* add a date if it doesn't include one (Mastodon) */
xs *date = xs_str_utctime(0, "%Y-%m-%dT%H:%M:%SZ");
f_msg = xs_dict_set(f_msg, "published", date);
}
timeline_add(snac, xs_dict_get(f_msg, "id"), f_msg);
follower_add(snac, actor);
snac_log(snac, xs_fmt("new follower %s", actor));
do_notify = 1;
}
else
snac_log(snac, xs_fmt("repeated 'Follow' from %s", actor));
}
else
if (strcmp(type, "Undo") == 0) {
if (strcmp(utype, "Follow") == 0) {
if (valid_status(follower_del(snac, actor))) {
snac_log(snac, xs_fmt("no longer following us %s", actor));
do_notify = 1;
}
else
snac_log(snac, xs_fmt("error deleting follower %s", actor));
}
else
snac_debug(snac, 1, xs_fmt("ignored 'Undo' for object type '%s'", utype));
}
else
if (strcmp(type, "Create") == 0) {
if (strcmp(utype, "Note") == 0) {
if (is_muted(snac, actor))
snac_log(snac, xs_fmt("ignored 'Note' from muted actor %s", actor));
else {
char *id = xs_dict_get(object, "id");
char *in_reply_to = xs_dict_get(object, "inReplyTo");
xs *wrk = NULL;
timeline_request(snac, &in_reply_to, &wrk);
if (timeline_add(snac, id, object)) {
snac_log(snac, xs_fmt("new 'Note' %s %s", actor, id));
do_notify = 1;
}
}
}
else
snac_debug(snac, 1, xs_fmt("ignored 'Create' for object type '%s'", utype));
}
else
if (strcmp(type, "Accept") == 0) {
if (strcmp(utype, "Follow") == 0) {
if (following_check(snac, actor)) {
following_add(snac, actor, msg);
snac_log(snac, xs_fmt("confirmed follow from %s", actor));
}
else
snac_log(snac, xs_fmt("spurious follow accept from %s", actor));
}
else
snac_debug(snac, 1, xs_fmt("ignored 'Accept' for object type '%s'", utype));
}
else
if (strcmp(type, "Like") == 0) {
if (xs_type(object) == XSTYPE_DICT)
object = xs_dict_get(object, "id");
timeline_admire(snac, object, actor, 1);
snac_log(snac, xs_fmt("new 'Like' %s %s", actor, object));
do_notify = 1;
}
else
if (strcmp(type, "Announce") == 0) {
xs *a_msg = NULL;
xs *wrk = NULL;
if (xs_type(object) == XSTYPE_DICT)
object = xs_dict_get(object, "id");
timeline_request(snac, &object, &wrk);
if (valid_status(object_get(object, &a_msg))) {
char *who = xs_dict_get(a_msg, "attributedTo");
if (who && !is_muted(snac, who)) {
/* bring the actor */
xs *who_o = NULL;
if (valid_status(actor_request(snac, who, &who_o))) {
timeline_admire(snac, object, actor, 0);
snac_log(snac, xs_fmt("new 'Announce' %s %s", actor, object));
do_notify = 1;
}
else
snac_log(snac, xs_fmt("dropped 'Announce' on actor request error %s", who));
}
else
snac_log(snac, xs_fmt("ignored 'Announce' about muted actor %s", who));
}
else
snac_log(snac, xs_fmt("error requesting 'Announce' object %s", object));
}
else
if (strcmp(type, "Update") == 0) {
if (strcmp(utype, "Person") == 0) {
actor_add(actor, xs_dict_get(msg, "object"));
snac_log(snac, xs_fmt("updated actor %s", actor));
}
else
if (strcmp(utype, "Note") == 0) {
char *id = xs_dict_get(object, "id");
object_add_ow(id, object);
snac_log(snac, xs_fmt("updated post %s", id));
}
else
snac_log(snac, xs_fmt("ignored 'Update' for object type '%s'", utype));
}
else
if (strcmp(type, "Delete") == 0) {
if (xs_type(object) == XSTYPE_DICT)
object = xs_dict_get(object, "id");
if (valid_status(timeline_del(snac, object)))
snac_debug(snac, 1, xs_fmt("new 'Delete' %s %s", actor, object));
else
snac_debug(snac, 1, xs_fmt("ignored 'Delete' for unknown object %s", object));
}
else
if (strcmp(type, "Pong") == 0) {
snac_log(snac, xs_fmt("'Pong' received from %s", actor));
}
else
if (strcmp(type, "Ping") == 0) {
snac_log(snac, xs_fmt("'Ping' requested from %s", actor));
xs *rsp = msg_pong(snac, actor, xs_dict_get(msg, "id"));
enqueue_output_by_actor(snac, rsp, actor, 0);
}
else
snac_debug(snac, 1, xs_fmt("process_input_message type '%s' ignored", type));
if (do_notify) {
notify(snac, type, utype, actor, msg);
timeline_touch(snac);
}
return 1;
}
int send_email(char *msg)
/* invoke sendmail with email headers and body in msg */
{
FILE *f;
int status;
int fds[2];
pid_t pid;
if (pipe(fds) == -1) return -1;
pid = vfork();
if (pid == -1) return -1;
else if (pid == 0) {
dup2(fds[0], 0);
close(fds[0]);
close(fds[1]);
execl("/usr/sbin/sendmail", "sendmail", "-t", (char *) NULL);
_exit(1);
}
close(fds[0]);
if ((f = fdopen(fds[1], "w")) == NULL) {
close(fds[1]);
return -1;
}
fprintf(f, "%s\n", msg);
fclose(f);
if (waitpid(pid, &status, 0) == -1) return -1;
return status;
}
void process_user_queue_item(snac *snac, xs_dict *q_item)
/* processes an item from the user queue */
{
char *type;
int queue_retry_max = xs_number_get(xs_dict_get(srv_config, "queue_retry_max"));
if ((type = xs_dict_get(q_item, "type")) == NULL)
type = "output";
if (strcmp(type, "message") == 0) {
xs_dict *msg = xs_dict_get(q_item, "message");
xs *rcpts = recipient_list(snac, msg, 1);
xs_set inboxes;
xs_list *p;
xs_str *actor;
xs_set_init(&inboxes);
/* iterate the recipients */
p = rcpts;
while (xs_list_iter(&p, &actor)) {
xs *inbox = get_actor_inbox(snac, actor);
if (inbox != NULL) {
/* add to the set and, if it's not there, send message */
if (xs_set_add(&inboxes, inbox) == 1)
enqueue_output(snac, msg, inbox, 0);
}
else
snac_log(snac, xs_fmt("cannot find inbox for %s", actor));
}
/* if it's public, send to the collected inboxes */
if (is_msg_public(snac, msg)) {
xs *shibx = inbox_list();
xs_str *inbox;
p = shibx;
while (xs_list_iter(&p, &inbox)) {
if (xs_set_add(&inboxes, inbox) == 1)
enqueue_output(snac, msg, inbox, 0);
}
}
xs_set_free(&inboxes);
}
else
if (strcmp(type, "input") == 0) {
/* process the message */
xs_dict *msg = xs_dict_get(q_item, "message");
xs_dict *req = xs_dict_get(q_item, "req");
int retries = xs_number_get(xs_dict_get(q_item, "retries"));
if (xs_is_null(msg))
return;
if (!process_input_message(snac, msg, req)) {
if (retries > queue_retry_max)
snac_log(snac, xs_fmt("input giving up"));
else {
/* reenqueue */
enqueue_input(snac, msg, req, retries + 1);
snac_log(snac, xs_fmt("input requeue #%d", retries + 1));
}
}
}
else
snac_log(snac, xs_fmt("unexpected q_item type '%s'", type));
}
int process_user_queue(snac *snac)
/* processes a user's queue */
{
int cnt = 0;
xs *list = user_queue(snac);
xs_list *p = list;
xs_str *fn;
while (xs_list_iter(&p, &fn)) {
xs *q_item = dequeue(fn);
if (q_item == NULL) {
snac_log(snac, xs_fmt("process_user_queue q_item error"));
continue;
}
process_user_queue_item(snac, q_item);
cnt++;
}
return cnt;
}
void process_queue_item(xs_dict *q_item)
/* processes an item from the global queue */
{
char *type = xs_dict_get(q_item, "type");
int queue_retry_max = xs_number_get(xs_dict_get(srv_config, "queue_retry_max"));
if (strcmp(type, "output") == 0) {
int status;
xs_str *inbox = xs_dict_get(q_item, "inbox");
xs_str *keyid = xs_dict_get(q_item, "keyid");
xs_str *seckey = xs_dict_get(q_item, "seckey");
xs_dict *msg = xs_dict_get(q_item, "message");
int retries = xs_number_get(xs_dict_get(q_item, "retries"));
xs *payload = NULL;
int p_size = 0;
if (xs_is_null(inbox) || xs_is_null(msg) || xs_is_null(keyid) || xs_is_null(seckey)) {
srv_log(xs_fmt("output message error: missing fields"));
return;
}
/* deliver */
status = send_to_inbox_raw(keyid, seckey, inbox, msg, &payload, &p_size, retries == 0 ? 3 : 8);
if (payload) {
if (p_size > 64) {
/* trim the message */
payload[64] = '\0';
payload = xs_str_cat(payload, "...");
}
/* strip ugly control characters */
payload = xs_replace_i(payload, "\n", "");
payload = xs_replace_i(payload, "\r", "");
if (*payload)
payload = xs_str_wrap_i(" [", payload, "]");
}
else
payload = xs_str_new(NULL);
srv_log(xs_fmt("output message: sent to inbox %s %d%s", inbox, status, payload));
if (!valid_status(status)) {
retries++;
/* error sending; requeue? */
if (status == 404 || status == 410)
/* explicit error: discard */
srv_log(xs_fmt("output message: fatal error %s %d", inbox, status));
else
if (retries > queue_retry_max)
srv_log(xs_fmt("output message: giving up %s %d", inbox, status));
else {
/* requeue */
enqueue_output_raw(keyid, seckey, msg, inbox, retries);
srv_log(xs_fmt("output message: requeue %s #%d", inbox, retries));
}
}
}
else
if (strcmp(type, "email") == 0) {
/* send this email */
xs_str *msg = xs_dict_get(q_item, "message");
int retries = xs_number_get(xs_dict_get(q_item, "retries"));
if (!send_email(msg))
srv_debug(1, xs_fmt("email message sent"));
else {
retries++;
if (retries > queue_retry_max)
srv_log(xs_fmt("email giving up (errno: %d)", errno));
else {
/* requeue */
srv_log(xs_fmt(
"email requeue #%d (errno: %d)", retries, errno));
enqueue_email(msg, retries);
}
}
}
else
if (strcmp(type, "telegram") == 0) {
/* send this via telegram */
char *bot = xs_dict_get(q_item, "bot");
char *msg = xs_dict_get(q_item, "message");
xs *chat_id = xs_dup(xs_dict_get(q_item, "chat_id"));
int status = 0;
/* chat_id must start with a - */
if (!xs_startswith(chat_id, "-"))
chat_id = xs_str_wrap_i("-", chat_id, NULL);
xs *url = xs_fmt("https:/" "/api.telegram.org/bot%s/sendMessage", bot);
xs *body = xs_fmt("{\"chat_id\":%s,\"text\":\"%s\"}", chat_id, msg);
xs *headers = xs_dict_new();
headers = xs_dict_append(headers, "content-type", "application/json");
xs *rsp = xs_http_request("POST", url, headers,
body, strlen(body), &status, NULL, NULL, 0);
rsp = xs_free(rsp);
srv_debug(0, xs_fmt("telegram post %d", status));
}
else
if (strcmp(type, "purge") == 0) {
srv_log(xs_dup("purge start"));
purge_all();
srv_log(xs_dup("purge end"));
}
else
srv_log(xs_fmt("unexpected q_item type '%s'", type));
}
int process_queue(void)
/* processes the global queue */
{
int cnt = 0;
xs *list = queue();
xs_list *p = list;
xs_str *fn;
while (xs_list_iter(&p, &fn)) {
xs *q_item = dequeue(fn);
if (q_item != NULL) {
job_post(q_item, 0);
cnt++;
}
}
return cnt;
}
/** HTTP handlers */
int activitypub_get_handler(const xs_dict *req, const char *q_path,
char **body, int *b_size, char **ctype)
{
int status = 200;
char *accept = xs_dict_get(req, "accept");
snac snac;
xs *msg = NULL;
if (accept == NULL)
return 0;
if (xs_str_in(accept, "application/activity+json") == -1 &&
xs_str_in(accept, "application/ld+json") == -1)
return 0;
xs *l = xs_split_n(q_path, "/", 2);
char *uid, *p_path;
uid = xs_list_get(l, 1);
if (!user_open(&snac, uid)) {
/* invalid user */
srv_debug(1, xs_fmt("activitypub_get_handler bad user %s", uid));
return 404;
}
p_path = xs_list_get(l, 2);
*ctype = "application/activity+json";
if (p_path == NULL) {
/* if there was no component after the user, it's an actor request */
msg = msg_actor(&snac);
*ctype = "application/ld+json; profile=\"https://www.w3.org/ns/activitystreams\"";
char *ua = xs_dict_get(req, "user-agent");
snac_debug(&snac, 0, xs_fmt("serving actor [%s]", ua ? ua : "No UA"));
}
else
if (strcmp(p_path, "outbox") == 0) {
xs *id = xs_fmt("%s/outbox", snac.actor);
xs *elems = timeline_simple_list(&snac, "public", 0, 20);
xs *list = xs_list_new();
msg = msg_collection(&snac, id);
char *p, *v;
p = elems;
while (xs_list_iter(&p, &v)) {
xs *i = NULL;
if (valid_status(object_get_by_md5(v, &i))) {
char *type = xs_dict_get(i, "type");
char *id = xs_dict_get(i, "id");
if (type && id && strcmp(type, "Note") == 0 && xs_startswith(id, snac.actor)) {
i = xs_dict_del(i, "_snac");
list = xs_list_append(list, i);
}
}
}
/* replace the 'orderedItems' with the latest posts */
xs *items = xs_number_new(xs_list_len(list));
msg = xs_dict_set(msg, "orderedItems", list);
msg = xs_dict_set(msg, "totalItems", items);
}
else
if (strcmp(p_path, "followers") == 0 || strcmp(p_path, "following") == 0) {
xs *id = xs_fmt("%s/%s", snac.actor, p_path);
msg = msg_collection(&snac, id);
}
else
if (xs_startswith(p_path, "p/")) {
xs *id = xs_fmt("%s/%s", snac.actor, p_path);
status = object_get(id, &msg);
}
else
status = 404;
if (status == 200 && msg != NULL) {
*body = xs_json_dumps_pp(msg, 4);
*b_size = strlen(*body);
}
snac_debug(&snac, 1, xs_fmt("activitypub_get_handler serving %s %d", q_path, status));
user_free(&snac);
return status;
}
int activitypub_post_handler(const xs_dict *req, const char *q_path,
char *payload, int p_size,
char **body, int *b_size, char **ctype)
/* processes an input message */
{
(void)b_size;
int status = 202; /* accepted */
char *i_ctype = xs_dict_get(req, "content-type");
snac snac;
char *v;
if (i_ctype == NULL) {
*body = xs_str_new("no content-type");
*ctype = "text/plain";
return 400;
}
if (xs_str_in(i_ctype, "application/activity+json") == -1 &&
xs_str_in(i_ctype, "application/ld+json") == -1)
return 0;
/* decode the message */
xs *msg = xs_json_loads(payload);
if (msg == NULL) {
srv_log(xs_fmt("activitypub_post_handler JSON error %s", q_path));
*body = xs_str_new("JSON error");
*ctype = "text/plain";
status = 400;
}
/* get the user and path */
xs *l = xs_split_n(q_path, "/", 2);
char *uid;
if (xs_list_len(l) != 3 || strcmp(xs_list_get(l, 2), "inbox") != 0) {
/* strange q_path */
srv_debug(1, xs_fmt("activitypub_post_handler unsupported path %s", q_path));
return 404;
}
uid = xs_list_get(l, 1);
if (!user_open(&snac, uid)) {
/* invalid user */
srv_debug(1, xs_fmt("activitypub_post_handler bad user %s", uid));
return 404;
}
/* if it has a digest, check it now, because
later the payload won't be exactly the same */
if ((v = xs_dict_get(req, "digest")) != NULL) {
xs *s1 = xs_sha256_base64(payload, p_size);
xs *s2 = xs_fmt("SHA-256=%s", s1);
if (strcmp(s2, v) != 0) {
srv_log(xs_fmt("digest check FAILED"));
*body = xs_str_new("bad digest");
*ctype = "text/plain";
status = 400;
}
}
/* if the message is from a muted actor, reject it right now */
if (!xs_is_null(v = xs_dict_get(msg, "actor")) && *v) {
if (is_muted(&snac, v)) {
srv_log(xs_fmt("rejected message from MUTEd actor %s", v));
*body = xs_str_new("rejected");
*ctype = "text/plain";
status = 403;
}
}
if (valid_status(status)) {
enqueue_input(&snac, msg, req, 0);
*ctype = "application/activity+json";
}
user_free(&snac);
return status;
}