2.59 activitypub.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_json.h"
   6#include "xs_curl.h"
   7#include "xs_mime.h"
   8#include "xs_openssl.h"
   9#include "xs_regex.h"
  10#include "xs_time.h"
  11#include "xs_set.h"
  12#include "xs_match.h"
  13
  14#include "snac.h"
  15
  16#include <sys/wait.h>
  17
  18const char *public_address = "https:/" "/www.w3.org/ns/activitystreams#Public";
  19
  20/* susie.png */
  21
  22const char *susie =
  23    "iVBORw0KGgoAAAANSUhEUgAAAEAAAABAAQAAAAC"
  24    "CEkxzAAAAUUlEQVQoz43R0QkAMQwCUDdw/y3dwE"
  25    "vsvzlL4X1IoQkAisKmwfAFT3RgJHbQezpSRoXEq"
  26    "eqCL9BJBf7h3QbOCCxV5EVWMEMwG7K1/WODtlvx"
  27    "AYTtEsDU9F34AAAAAElFTkSuQmCC";
  28
  29const char *susie_cool =
  30    "iVBORw0KGgoAAAANSUhEUgAAAEAAAABAAQAAAAC"
  31    "CEkxzAAAAV0lEQVQoz43RwQ3AMAwCQDZg/y3ZgN"
  32    "qo3+JaedwDOUQBQFHYaTB8wTM6sGl2cMPu+DFzn"
  33    "+ZcgN7wF7ZVihXkfSlWIVzIA6dbQzaygllpNuTX"
  34    "ZmmFNlvxADX1+o0cUPMbAAAAAElFTkSuQmCC";
  35
  36const char *susie_muertos = 
  37    "iVBORw0KGgoAAAANSUhEUgAAAEAAAABAAQAAAAC"
  38    "CEkxzAAAAV0lEQVQoz4XQsQ0AMQxCUW/A/lv+DT"
  39    "ic6zGRolekIMyMELNp8PiCEw6Q4w4NoAt53IH5m"
  40    "xXksrZYgZwJrIox+Z8vJAfe2lCxG6AK7eKkWcEb"
  41    "QHbF617xAQatAAD7jJHUAAAAAElFTkSuQmCC";
  42
  43
  44const char *default_avatar_base64(void)
  45/* returns the default avatar in base64 */
  46{
  47    time_t t = time(NULL);
  48    struct tm tm;
  49    const char *p = susie;
  50
  51    gmtime_r(&t, &tm);
  52
  53    if (tm.tm_mon == 10 && tm.tm_mday == 2)
  54        p = susie_muertos;
  55    else
  56    if (tm.tm_wday == 0 || tm.tm_wday == 6)
  57        p = susie_cool;
  58
  59    return p;
  60}
  61
  62
  63int activitypub_request(snac *user, const char *url, xs_dict **data)
  64/* request an object */
  65{
  66    int status = 0;
  67    xs *response = NULL;
  68    xs *payload = NULL;
  69    int p_size;
  70    const char *ctype;
  71
  72    *data = NULL;
  73
  74    if (user != NULL) {
  75        /* get from the net */
  76        response = http_signed_request(user, "GET", url,
  77            NULL, NULL, 0, &status, &payload, &p_size, 0);
  78    }
  79
  80    if (status == 0 || (status >= 500 && status <= 599)) {
  81        /* I found an instance running Misskey that returned
  82           500 on signed messages but returned the object
  83           perfectly without signing (?), so why not try */
  84        xs_free(response);
  85
  86        xs *hdrs = xs_dict_new();
  87        hdrs = xs_dict_append(hdrs, "accept",     "application/activity+json");
  88        hdrs = xs_dict_append(hdrs, "user-agent", USER_AGENT);
  89
  90        response = xs_http_request("GET", url, hdrs,
  91            NULL, 0, &status, &payload, &p_size, 0);
  92    }
  93
  94    if (valid_status(status)) {
  95        /* ensure it's ActivityPub data */
  96        ctype = xs_dict_get(response, "content-type");
  97
  98        if (xs_is_null(ctype))
  99            status = HTTP_STATUS_BAD_REQUEST;
 100        else
 101        if (xs_str_in(ctype, "application/activity+json") != -1 ||
 102            xs_str_in(ctype, "application/ld+json") != -1) {
 103
 104            /* if there is no payload, fail */
 105            if (xs_is_null(payload))
 106                status = HTTP_STATUS_BAD_REQUEST;
 107            else
 108                *data = xs_json_loads(payload);
 109        }
 110        else
 111            status = HTTP_STATUS_INTERNAL_SERVER_ERROR;
 112    }
 113
 114    return status;
 115}
 116
 117
 118int actor_request(snac *user, const char *actor, xs_dict **data)
 119/* request an actor */
 120{
 121    int status;
 122    xs *payload = NULL;
 123
 124    if (data)
 125        *data = NULL;
 126
 127    /* get from disk first */
 128    status = actor_get_refresh(user, actor, data);
 129
 130    if (!valid_status(status)) {
 131        /* actor data non-existent: get from the net */
 132        status = activitypub_request(user, actor, &payload);
 133
 134        if (valid_status(status)) {
 135            /* renew data */
 136            status = actor_add(actor, payload);
 137
 138            if (data != NULL) {
 139                *data   = payload;
 140                payload = NULL;
 141            }
 142        }
 143        else
 144            srv_debug(1, xs_fmt("actor_request error %s %d", actor, status));
 145    }
 146
 147    /* collect the (presumed) shared inbox in this actor */
 148    if (xs_type(xs_dict_get(srv_config, "disable_inbox_collection")) != XSTYPE_TRUE) {
 149        if (valid_status(status) && data && *data)
 150            inbox_add_by_actor(*data);
 151    }
 152
 153    return status;
 154}
 155
 156
 157const char *get_atto(const xs_dict *msg)
 158/* gets the attributedTo field (an actor) */
 159{
 160    const xs_val *actor = xs_dict_get(msg, "attributedTo");
 161
 162    /* if the actor is a list of objects (like on Peertube videos), pick the Person */
 163    if (xs_type(actor) == XSTYPE_LIST) {
 164        const xs_list *p = actor;
 165        int c = 0;
 166        const xs_dict *v;
 167        actor = NULL;
 168
 169        while (actor == NULL && xs_list_next(p, &v, &c)) {
 170            if (xs_type(v) == XSTYPE_DICT) {
 171                const char *type = xs_dict_get(v, "type");
 172                if (xs_type(type) == XSTYPE_STRING && strcmp(type, "Person") == 0) {
 173                    actor = xs_dict_get(v, "id");
 174
 175                    if (xs_type(actor) != XSTYPE_STRING)
 176                        actor = NULL;
 177                }
 178            }
 179        }
 180    }
 181
 182    return actor;
 183}
 184
 185
 186xs_list *get_attachments(const xs_dict *msg)
 187/* unify the garbage fire that are the attachments */
 188{
 189    xs_list *l = xs_list_new();
 190    const xs_list *p;
 191
 192    /* try first the attachments list */
 193    if (!xs_is_null(p = xs_dict_get(msg, "attachment"))) {
 194        xs *attach = NULL;
 195        const xs_val *v;
 196
 197        /* ensure it's a list */
 198        if (xs_type(p) == XSTYPE_DICT) {
 199            attach = xs_list_new();
 200            attach = xs_list_append(attach, p);
 201        }
 202        else
 203            attach = xs_dup(p);
 204
 205        if (xs_type(attach) == XSTYPE_LIST) {
 206            /* does the message have an image? */
 207            const xs_dict *d = xs_dict_get(msg, "image");
 208            if (xs_type(d) == XSTYPE_DICT) {
 209                /* add it to the attachment list */
 210                attach = xs_list_append(attach, d);
 211            }
 212        }
 213
 214        /* now iterate the list */
 215        int c = 0;
 216        while (xs_list_next(attach, &v, &c)) {
 217            const char *type = xs_dict_get(v, "mediaType");
 218            if (xs_is_null(type))
 219                type = xs_dict_get(v, "type");
 220
 221            if (xs_is_null(type))
 222                continue;
 223
 224            const char *href = xs_dict_get(v, "url");
 225            if (xs_is_null(href))
 226                href = xs_dict_get(v, "href");
 227            if (xs_is_null(href))
 228                continue;
 229
 230            /* infer MIME type from non-specific attachments */
 231            if (xs_list_len(attach) < 2 && xs_match(type, "Link|Document")) {
 232                char *mt = (char *)xs_mime_by_ext(href);
 233
 234                if (xs_match(mt, "image/*|audio/*|video/*")) /* */
 235                    type = mt;
 236            }
 237
 238            const char *name = xs_dict_get(v, "name");
 239            if (xs_is_null(name))
 240                name = xs_dict_get(msg, "name");
 241            if (xs_is_null(name))
 242                name = "";
 243
 244            xs *d = xs_dict_new();
 245            d = xs_dict_append(d, "type", type);
 246            d = xs_dict_append(d, "href", href);
 247            d = xs_dict_append(d, "name", name);
 248
 249            l = xs_list_append(l, d);
 250        }
 251    }
 252
 253    /** urls (attachments from Peertube) **/
 254    p = xs_dict_get(msg, "url");
 255
 256    if (xs_type(p) == XSTYPE_LIST) {
 257        const char *href = NULL;
 258        const char *type = NULL;
 259        int c = 0;
 260        const xs_val *v;
 261
 262        while (href == NULL && xs_list_next(p, &v, &c)) {
 263            if (xs_type(v) == XSTYPE_DICT) {
 264                const char *mtype = xs_dict_get(v, "type");
 265
 266                if (xs_type(mtype) == XSTYPE_STRING && strcmp(mtype, "Link") == 0) {
 267                    mtype = xs_dict_get(v, "mediaType");
 268                    const xs_list *tag = xs_dict_get(v, "tag");
 269
 270                    if (xs_type(mtype) == XSTYPE_STRING &&
 271                        strcmp(mtype, "application/x-mpegURL") == 0 &&
 272                        xs_type(tag) == XSTYPE_LIST) {
 273                        /* now iterate the tag list, looking for a video URL */
 274                        const xs_dict *d;
 275                        int c = 0;
 276
 277                        while (href == NULL && xs_list_next(tag, &d, &c)) {
 278                            if (xs_type(d) == XSTYPE_DICT) {
 279                                if (xs_type(mtype = xs_dict_get(d, "mediaType")) == XSTYPE_STRING &&
 280                                    xs_startswith(mtype, "video/")) {
 281                                    const char *h = xs_dict_get(d, "href");
 282
 283                                    /* this is probably it */
 284                                    if (xs_type(h) == XSTYPE_STRING) {
 285                                        href = h;
 286                                        type = mtype;
 287                                    }
 288                                }
 289                            }
 290                        }
 291                    }
 292                }
 293            }
 294        }
 295
 296        if (href && type) {
 297            xs *d = xs_dict_new();
 298            d = xs_dict_append(d, "href", href);
 299            d = xs_dict_append(d, "type", type);
 300            d = xs_dict_append(d, "name", "---");
 301
 302            l = xs_list_append(l, d);
 303        }
 304    }
 305
 306    return l;
 307}
 308
 309
 310int timeline_request(snac *snac, const char **id, xs_str **wrk, int level)
 311/* ensures that an entry and its ancestors are in the timeline */
 312{
 313    int status = 0;
 314
 315    if (level < MAX_CONVERSATION_LEVELS && !xs_is_null(*id)) {
 316        xs *msg = NULL;
 317
 318        /* from a blocked instance? discard and break */
 319        if (is_instance_blocked(*id)) {
 320            snac_debug(snac, 1, xs_fmt("timeline_request blocked instance %s", *id));
 321            return status;
 322        }
 323
 324        /* is the object already there? */
 325        if (!valid_status(object_get(*id, &msg))) {
 326            /* no; download it */
 327            status = activitypub_request(snac, *id, &msg);
 328
 329            if (valid_status(status)) {
 330                const xs_dict *object = msg;
 331                const char *type = xs_dict_get(object, "type");
 332
 333                /* get the id again from the object, as it may be different */
 334                const char *nid = xs_dict_get(object, "id");
 335
 336                if (xs_type(nid) != XSTYPE_STRING)
 337                    return 0;
 338
 339                if (wrk && strcmp(nid, *id) != 0) {
 340                    snac_debug(snac, 1,
 341                        xs_fmt("timeline_request canonical id for %s is %s", *id, nid));
 342
 343                    *wrk = xs_dup(nid);
 344                    *id  = *wrk;
 345                }
 346
 347                if (xs_is_null(type))
 348                    type = "(null)";
 349
 350                srv_debug(2, xs_fmt("timeline_request type %s '%s'", nid, type));
 351
 352                if (strcmp(type, "Create") == 0) {
 353                    /* some software like lemmy nest Announce + Create + Note */
 354                    if (!xs_is_null(object = xs_dict_get(object, "object"))) {
 355                        type = xs_dict_get(object, "type");
 356                        nid  = xs_dict_get(object, "id");
 357                    }
 358                    else
 359                        type = "(null)";
 360                }
 361
 362                if (xs_match(type, POSTLIKE_OBJECT_TYPE)) {
 363                    if (content_match("filter_reject.txt", object))
 364                        snac_log(snac, xs_fmt("timeline_request rejected by content %s", nid));
 365                    else {
 366                        const char *actor = get_atto(object);
 367
 368                        if (!xs_is_null(actor)) {
 369                            /* request (and drop) the actor for this entry */
 370                            if (!valid_status(actor_request(snac, actor, NULL))) {
 371                                /* failed? retry later */
 372                                enqueue_actor_refresh(snac, actor, 60);
 373                            }
 374
 375                            /* does it have an ancestor? */
 376                            const char *in_reply_to = xs_dict_get(object, "inReplyTo");
 377
 378                            /* store */
 379                            timeline_add(snac, nid, object);
 380
 381                            /* recurse! */
 382                            timeline_request(snac, &in_reply_to, NULL, level + 1);
 383                        }
 384                    }
 385                }
 386            }
 387        }
 388    }
 389
 390    return status;
 391}
 392
 393
 394int send_to_inbox_raw(const char *keyid, const char *seckey,
 395                  const xs_str *inbox, const xs_dict *msg,
 396                  xs_val **payload, int *p_size, int timeout)
 397/* sends a message to an Inbox */
 398{
 399    int status;
 400    xs_dict *response;
 401    xs *j_msg = xs_json_dumps((xs_dict *)msg, 4);
 402
 403    response = http_signed_request_raw(keyid, seckey, "POST", inbox,
 404        NULL, j_msg, strlen(j_msg), &status, payload, p_size, timeout);
 405
 406    xs_free(response);
 407
 408    return status;
 409}
 410
 411
 412int send_to_inbox(snac *snac, const xs_str *inbox, const xs_dict *msg,
 413                  xs_val **payload, int *p_size, int timeout)
 414/* sends a message to an Inbox */
 415{
 416    const char *seckey = xs_dict_get(snac->key, "secret");
 417
 418    return send_to_inbox_raw(snac->actor, seckey, inbox, msg, payload, p_size, timeout);
 419}
 420
 421
 422xs_str *get_actor_inbox(const char *actor)
 423/* gets an actor's inbox */
 424{
 425    xs *data = NULL;
 426    const char *v = NULL;
 427
 428    if (valid_status(actor_request(NULL, actor, &data))) {
 429        /* try first endpoints/sharedInbox */
 430        if ((v = xs_dict_get(data, "endpoints")))
 431            v = xs_dict_get(v, "sharedInbox");
 432
 433        /* try then the regular inbox */
 434        if (xs_is_null(v))
 435            v = xs_dict_get(data, "inbox");
 436    }
 437
 438    return xs_is_null(v) ? NULL : xs_dup(v);
 439}
 440
 441
 442int send_to_actor(snac *snac, const char *actor, const xs_dict *msg,
 443                  xs_val **payload, int *p_size, int timeout)
 444/* sends a message to an actor */
 445{
 446    int status = HTTP_STATUS_BAD_REQUEST;
 447    xs *inbox = get_actor_inbox(actor);
 448
 449    if (!xs_is_null(inbox))
 450        status = send_to_inbox(snac, inbox, msg, payload, p_size, timeout);
 451
 452    return status;
 453}
 454
 455
 456void post_message(snac *snac, const char *actor, const xs_dict *msg)
 457/* posts a message immediately (bypassing the output queues) */
 458{
 459    xs *payload = NULL;
 460    int p_size;
 461
 462    int status = send_to_actor(snac, actor, msg, &payload, &p_size, 3);
 463
 464    srv_log(xs_fmt("post_message to actor %s %d", actor, status));
 465
 466    if (!valid_status(status))
 467        /* cannot send right now, enqueue */
 468        enqueue_message(snac, msg);
 469}
 470
 471
 472xs_list *recipient_list(snac *snac, const xs_dict *msg, int expand_public)
 473/* returns the list of recipients for a message */
 474{
 475    const xs_val *to = xs_dict_get(msg, "to");
 476    const xs_val *cc = xs_dict_get(msg, "cc");
 477    xs_set rcpts;
 478    int n;
 479
 480    xs_set_init(&rcpts);
 481
 482    const xs_list *lists[] = { to, cc, NULL };
 483    for (n = 0; lists[n]; n++) {
 484        xs_list *l = (xs_list *)lists[n];
 485        const char *v;
 486        xs *tl = NULL;
 487
 488        /* if it's a string, create a list with only one element */
 489        if (xs_type(l) == XSTYPE_STRING) {
 490            tl = xs_list_new();
 491            tl = xs_list_append(tl, l);
 492
 493            l = tl;
 494        }
 495
 496        while (xs_list_iter(&l, &v)) {
 497            if (expand_public && strcmp(v, public_address) == 0) {
 498                /* iterate the followers and add them */
 499                xs *fwers = follower_list(snac);
 500                const char *actor;
 501
 502                char *p = fwers;
 503                while (xs_list_iter(&p, &actor))
 504                    xs_set_add(&rcpts, actor);
 505            }
 506            else
 507                xs_set_add(&rcpts, v);
 508        }
 509    }
 510
 511    return xs_set_result(&rcpts);
 512}
 513
 514
 515int is_msg_public(const xs_dict *msg)
 516/* checks if a message is public */
 517{
 518    const char *to = xs_dict_get(msg, "to");
 519    const char *cc = xs_dict_get(msg, "cc");
 520    int n;
 521
 522    const char *lists[] = { to, cc, NULL };
 523    for (n = 0; lists[n]; n++) {
 524        const xs_val *l = lists[n];
 525
 526        if (xs_type(l) == XSTYPE_STRING) {
 527            if (strcmp(l, public_address) == 0)
 528                return 1;
 529        }
 530        else
 531        if (xs_type(l) == XSTYPE_LIST) {
 532            if (xs_list_in(l, public_address) != -1)
 533                return 1;
 534        }
 535    }
 536
 537    return 0;
 538}
 539
 540
 541int is_msg_from_private_user(const xs_dict *msg)
 542/* checks if a message is from a local, private user */
 543{
 544    int ret = 0;
 545
 546    /* is this message from a local user? */
 547    if (xs_startswith(xs_dict_get(msg, "id"), srv_baseurl)) {
 548        const char *atto = get_atto(msg);
 549        xs *l = xs_split(atto, "/");
 550        const char *uid = xs_list_get(l, -1);
 551        snac user;
 552
 553        if (uid && user_open(&user, uid)) {
 554            if (xs_type(xs_dict_get(user.config, "private")) == XSTYPE_TRUE)
 555                ret = 1;
 556
 557            user_free(&user);
 558        }
 559    }
 560
 561    return ret;
 562}
 563
 564
 565int is_msg_for_me(snac *snac, const xs_dict *c_msg)
 566/* checks if this message is for me */
 567{
 568    const char *type  = xs_dict_get(c_msg, "type");
 569    const char *actor = xs_dict_get(c_msg, "actor");
 570
 571    if (strcmp(actor, snac->actor) == 0) {
 572        /* message by myself? (most probably via the shared-inbox) reject */
 573        snac_debug(snac, 1, xs_fmt("ignoring message by myself"));
 574        return 0;
 575    }
 576
 577    if (xs_match(type, "Like|Announce|EmojiReact")) {
 578        const char *object = xs_dict_get(c_msg, "object");
 579
 580        if (xs_type(object) == XSTYPE_DICT)
 581            object = xs_dict_get(object, "id");
 582
 583        /* bad object id? reject */
 584        if (xs_type(object) != XSTYPE_STRING)
 585            return 0;
 586
 587        /* if it's about one of our posts, accept it */
 588        if (xs_startswith(object, snac->actor))
 589            return 2;
 590
 591        /* if it's by someone we don't follow, reject */
 592        return following_check(snac, actor);
 593    }
 594
 595    /* if it's an Undo, it must be from someone related to us */
 596    if (xs_match(type, "Undo")) {
 597        return follower_check(snac, actor) || following_check(snac, actor);
 598    }
 599
 600    /* if it's an Accept + Follow, it must be for a Follow we created */
 601    if (xs_match(type, "Accept")) {
 602        return following_check(snac, actor);
 603    }
 604
 605    /* if it's a Follow, it must be explicitly for us */
 606    if (xs_match(type, "Follow")) {
 607        const char *object = xs_dict_get(c_msg, "object");
 608        return !xs_is_null(object) && strcmp(snac->actor, object) == 0;
 609    }
 610
 611    /* only accept Ping directed to us */
 612    if (xs_match(type, "Ping")) {
 613        const char *dest = xs_dict_get(c_msg, "to");
 614        return !xs_is_null(dest) && strcmp(snac->actor, dest) == 0;
 615    }
 616
 617    /* if it's not a Create or Update, allow as is */
 618    if (!xs_match(type, "Create|Update")) {
 619        return 1;
 620    }
 621
 622    int pub_msg = is_msg_public(c_msg);
 623
 624    /* if this message is public and we follow the actor of this post, allow */
 625    if (pub_msg && following_check(snac, actor))
 626        return 1;
 627
 628    const xs_dict *msg = xs_dict_get(c_msg, "object");
 629    xs *rcpts = recipient_list(snac, msg, 0);
 630    xs_list *p = rcpts;
 631    const xs_str *v;
 632
 633    xs *actor_followers = NULL;
 634
 635    if (!pub_msg) {
 636        /* not a public message; get the actor and its followers list */
 637        xs *actor_obj = NULL;
 638
 639        if (valid_status(object_get(actor, &actor_obj))) {
 640            const xs_val *fw = xs_dict_get(actor_obj, "followers");
 641            if (fw)
 642                actor_followers = xs_dup(fw);
 643        }
 644    }
 645
 646    while(xs_list_iter(&p, &v)) {
 647        /* explicitly for me? accept */
 648        if (strcmp(v, snac->actor) == 0)
 649            return 2;
 650
 651        if (pub_msg) {
 652            /* a public message for someone we follow? (probably cc'ed) accept */
 653            if (following_check(snac, v))
 654                return 5;
 655        }
 656        else
 657        if (actor_followers && strcmp(v, actor_followers) == 0) {
 658            /* if this message is for this actor's followers, are we one of them? */
 659            if (following_check(snac, actor))
 660                return 6;
 661        }
 662    }
 663
 664    /* accept if it's by someone we follow */
 665    const char *atto = get_atto(msg);
 666
 667    if (pub_msg && !xs_is_null(atto) && following_check(snac, atto))
 668        return 3;
 669
 670    /* is this message a reply to another? */
 671    const char *irt = xs_dict_get(msg, "inReplyTo");
 672    if (!xs_is_null(irt)) {
 673        xs *r_msg = NULL;
 674
 675        /* try to get the replied message */
 676        if (valid_status(object_get(irt, &r_msg))) {
 677            atto = get_atto(r_msg);
 678
 679            /* accept if the replied message is from someone we follow */
 680            if (pub_msg && !xs_is_null(atto) && following_check(snac, atto))
 681                return 4;
 682        }
 683    }
 684
 685    return 0;
 686}
 687
 688
 689xs_str *process_tags(snac *snac, const char *content, xs_list **tag)
 690/* parses mentions and tags from content */
 691{
 692    xs_str *nc  = xs_str_new(NULL);
 693    xs_list *tl = *tag;
 694    xs *split;
 695    xs_list *p;
 696    const xs_val *v;
 697    int n = 0;
 698
 699    /* create a default server for incomplete mentions */
 700    xs *def_srv = NULL;
 701
 702    if (xs_list_len(tl)) {
 703        /* if there are any mentions, get the server from
 704           the first one, which is the inReplyTo author */
 705        p = tl;
 706        while (xs_list_iter(&p, &v)) {
 707            const char *type = xs_dict_get(v, "type");
 708            const char *name = xs_dict_get(v, "name");
 709
 710            if (type && name && strcmp(type, "Mention") == 0) {
 711                xs *l = xs_split(name, "@");
 712
 713                def_srv = xs_dup(xs_list_get(l, -1));
 714
 715                break;
 716            }
 717        }
 718    }
 719
 720    if (xs_is_null(def_srv))
 721        /* use this same server */
 722        def_srv = xs_dup(xs_dict_get(srv_config, "host"));
 723
 724    split = xs_regex_split(content, "(@[A-Za-z0-9_]+(@[A-Za-z0-9\\.-]+)?|&#[0-9]+;|#[^ ,\\.:;<]+)");
 725
 726    p = split;
 727    while (xs_list_iter(&p, &v)) {
 728        if ((n & 0x1)) {
 729            if (*v == '@') {
 730                xs *link = NULL;
 731                xs *wuid = NULL;
 732
 733                if (strchr(v + 1, '@') == NULL) {
 734                    /* only one @? it's a dumb Mastodon-like mention
 735                       without server; add the default one */
 736                    wuid = xs_fmt("%s@%s", v, def_srv);
 737
 738                    snac_debug(snac, 2, xs_fmt("mention without server '%s' '%s'", v, wuid));
 739                }
 740                else
 741                    wuid = xs_dup(v);
 742
 743                /* query the webfinger about this fellow */
 744                xs *actor = NULL;
 745                xs *uid   = NULL;
 746                int status;
 747
 748                status = webfinger_request(wuid, &actor, &uid);
 749
 750                if (valid_status(status) && actor && uid) {
 751                    xs *d = xs_dict_new();
 752                    xs *n = xs_fmt("@%s", uid);
 753
 754                    d = xs_dict_append(d, "type",   "Mention");
 755                    d = xs_dict_append(d, "href",   actor);
 756                    d = xs_dict_append(d, "name",   n);
 757
 758                    tl = xs_list_append(tl, d);
 759
 760                    link = xs_fmt("<a href=\"%s\" class=\"u-url h-card mention\">%s</a>", actor, n);
 761                }
 762
 763                if (!xs_is_null(link))
 764                    nc = xs_str_cat(nc, link);
 765                else
 766                    nc = xs_str_cat(nc, v);
 767            }
 768            else
 769            if (*v == '#') {
 770                /* hashtag */
 771                xs *d = xs_dict_new();
 772                xs *n = xs_tolower_i(xs_dup(v));
 773                xs *h = xs_fmt("%s?t=%s", srv_baseurl, n + 1);
 774                xs *l = xs_fmt("<a href=\"%s\" class=\"mention hashtag\" rel=\"tag\">%s</a>", h, v);
 775
 776                d = xs_dict_append(d, "type",   "Hashtag");
 777                d = xs_dict_append(d, "href",   h);
 778                d = xs_dict_append(d, "name",   n);
 779
 780                tl = xs_list_append(tl, d);
 781
 782                /* add the code */
 783                nc = xs_str_cat(nc, l);
 784            }
 785            else
 786            if (*v == '&') {
 787                /* HTML Unicode entity, probably part of an emoji */
 788
 789                /* write as is */
 790                nc = xs_str_cat(nc, v);
 791            }
 792        }
 793        else
 794            nc = xs_str_cat(nc, v);
 795
 796        n++;
 797    }
 798
 799    *tag = tl;
 800
 801    return nc;
 802}
 803
 804
 805void notify(snac *snac, const char *type, const char *utype, const char *actor, const xs_dict *msg)
 806/* notifies the user of relevant events */
 807{
 808    /* skip our own notifications */
 809    if (strcmp(snac->actor, actor) == 0)
 810        return;
 811
 812    const char *id = xs_dict_get(msg, "id");
 813
 814    if (strcmp(type, "Create") == 0) {
 815        /* only notify of notes specifically for us */
 816        xs *rcpts = recipient_list(snac, msg, 0);
 817
 818        if (xs_list_in(rcpts, snac->actor) == -1)
 819            return;
 820
 821        /* discard votes */
 822        const xs_dict *note = xs_dict_get(msg, "object");
 823
 824        if (note && !xs_is_null(xs_dict_get(note, "name")))
 825            return;
 826    }
 827
 828    if (strcmp(type, "Undo") == 0 && strcmp(utype, "Follow") != 0)
 829        return;
 830
 831    /* get the object id */
 832    const char *objid = xs_dict_get(msg, "object");
 833
 834    if (xs_type(objid) == XSTYPE_DICT)
 835        objid = xs_dict_get(objid, "id");
 836
 837    if (xs_match(type, "Like|Announce|EmojiReact")) {
 838        /* if it's not an admiration about something by us, done */
 839        if (xs_is_null(objid) || !xs_startswith(objid, snac->actor))
 840            return;
 841    }
 842
 843    /* updated poll? */
 844    if (strcmp(type, "Update") == 0 && strcmp(utype, "Question") == 0) {
 845        const xs_dict *poll;
 846        const char *poll_id;
 847
 848        if ((poll = xs_dict_get(msg, "object")) == NULL)
 849            return;
 850
 851        /* if it's not closed, discard */
 852        if (xs_is_null(xs_dict_get(poll, "closed")))
 853            return;
 854
 855        if ((poll_id = xs_dict_get(poll, "id")) == NULL)
 856            return;
 857
 858        /* if it's not ours and we didn't vote, discard */
 859        if (!xs_startswith(poll_id, snac->actor) && !was_question_voted(snac, poll_id))
 860            return;
 861    }
 862
 863    /* user will love to know about this! */
 864
 865    /* prepare message body */
 866    xs *body = xs_fmt("User  : @%s@%s\n",
 867        xs_dict_get(snac->config, "uid"),
 868        xs_dict_get(srv_config,   "host")
 869    );
 870
 871    if (strcmp(utype, "(null)") != 0) {
 872        xs *s1 = xs_fmt("Type  : %s + %s\n", type, utype);
 873        body = xs_str_cat(body, s1);
 874    }
 875    else {
 876        xs *s1 = xs_fmt("Type  : %s\n", type);
 877        body = xs_str_cat(body, s1);
 878    }
 879
 880    {
 881        xs *s1 = xs_fmt("Actor : %s\n", actor);
 882        body = xs_str_cat(body, s1);
 883    }
 884
 885    if (objid != NULL) {
 886        xs *s1 = xs_fmt("Object: %s\n", objid);
 887        body = xs_str_cat(body, s1);
 888    }
 889
 890    /* email */
 891
 892    const char *email = "[disabled by admin]";
 893
 894    if (xs_type(xs_dict_get(srv_config, "disable_email_notifications")) != XSTYPE_TRUE) {
 895        email = xs_dict_get(snac->config_o, "email");
 896        if (xs_is_null(email)) {
 897            email = xs_dict_get(snac->config, "email");
 898
 899            if (xs_is_null(email))
 900                email = "[empty]";
 901        }
 902    }
 903
 904    if (*email != '\0' && *email != '[') {
 905        snac_debug(snac, 1, xs_fmt("email notify %s %s %s", type, utype, actor));
 906
 907        xs *subject = xs_fmt("snac notify for @%s@%s",
 908                    xs_dict_get(snac->config, "uid"), xs_dict_get(srv_config, "host"));
 909        xs *from    = xs_fmt("snac-daemon <snac-daemon@%s>", xs_dict_get(srv_config, "host"));
 910        xs *header  = xs_fmt(
 911                    "From: %s\n"
 912                    "To: %s\n"
 913                    "Subject: %s\n"
 914                    "\n",
 915                    from, email, subject);
 916
 917        xs *email_body = xs_fmt("%s%s", header, body);
 918
 919        enqueue_email(email_body, 0);
 920    }
 921
 922    /* telegram */
 923
 924    const char *bot     = xs_dict_get(snac->config, "telegram_bot");
 925    const char *chat_id = xs_dict_get(snac->config, "telegram_chat_id");
 926
 927    if (!xs_is_null(bot) && !xs_is_null(chat_id) && *bot && *chat_id)
 928        enqueue_telegram(body, bot, chat_id);
 929
 930    /* ntfy */
 931    const char *ntfy_server = xs_dict_get(snac->config, "ntfy_server");
 932    const char *ntfy_token  = xs_dict_get(snac->config, "ntfy_token");
 933
 934    if (!xs_is_null(ntfy_server) && *ntfy_server)
 935        enqueue_ntfy(body, ntfy_server, ntfy_token);
 936
 937    /* auto boost */
 938    if (xs_match(type, "Create") && xs_is_true(xs_dict_get(snac->config, "auto_boost"))) {
 939        xs *msg = msg_admiration(snac, objid, "Announce");
 940        enqueue_message(snac, msg);
 941
 942        snac_debug(snac, 1, xs_fmt("auto boosted %s", objid));
 943    }
 944
 945    /* finally, store it in the notification folder */
 946    if (strcmp(type, "Follow") == 0)
 947        objid = id;
 948    else
 949    if (strcmp(utype, "Follow") == 0)
 950        objid = actor;
 951
 952    notify_add(snac, type, utype, actor, objid != NULL ? objid : id, msg);
 953}
 954
 955/** messages **/
 956
 957xs_dict *msg_base(snac *snac, const char *type, const char *id,
 958                  const char *actor, const char *date, const char *object)
 959/* creates a base ActivityPub message */
 960{
 961    xs *did       = NULL;
 962    xs *published = NULL;
 963    xs *ntid      = tid(0);
 964    const char *obj_id;
 965
 966    if (xs_type(object) == XSTYPE_DICT)
 967        obj_id = xs_dict_get(object, "id");
 968    else
 969        obj_id = object;
 970
 971    /* generated values */
 972    if (date && strcmp(date, "@now") == 0) {
 973        published = xs_str_utctime(0, ISO_DATE_SPEC);
 974        date = published;
 975    }
 976
 977    if (id != NULL) {
 978        if (strcmp(id, "@dummy") == 0) {
 979            did = xs_fmt("%s/d/%s/%s", snac->actor, ntid, type);
 980
 981            id = did;
 982        }
 983        else
 984        if (strcmp(id, "@object") == 0) {
 985            if (obj_id != NULL) {
 986                did = xs_fmt("%s/%s_%s", obj_id, type, ntid);
 987                id = did;
 988            }
 989            else
 990                id = NULL;
 991        }
 992        else
 993        if (strcmp(id, "@wrapper") == 0) {
 994            /* like @object, but always generate the same id */
 995            if (object != NULL) {
 996                date = xs_dict_get(object, "published");
 997                did = xs_fmt("%s/%s", obj_id, type);
 998                id = did;
 999            }
1000            else
1001                id = NULL;
1002        }
1003    }
1004
1005    xs_dict *msg = xs_dict_new();
1006
1007    msg = xs_dict_append(msg, "@context", "https:/" "/www.w3.org/ns/activitystreams");
1008    msg = xs_dict_append(msg, "type",     type);
1009
1010    if (id != NULL)
1011        msg = xs_dict_append(msg, "id", id);
1012
1013    if (actor != NULL)
1014        msg = xs_dict_append(msg, "actor", actor);
1015
1016    if (date != NULL)
1017        msg = xs_dict_append(msg, "published", date);
1018
1019    if (object != NULL)
1020        msg = xs_dict_append(msg, "object", object);
1021
1022    return msg;
1023}
1024
1025
1026xs_dict *msg_collection(snac *snac, const char *id)
1027/* creates an empty OrderedCollection message */
1028{
1029    xs_dict *msg = msg_base(snac, "OrderedCollection", id, NULL, NULL, NULL);
1030    xs *ol = xs_list_new();
1031
1032    msg = xs_dict_append(msg, "attributedTo", snac->actor);
1033    msg = xs_dict_append(msg, "orderedItems", ol);
1034    msg = xs_dict_append(msg, "totalItems",   xs_stock(0));
1035
1036    return msg;
1037}
1038
1039
1040xs_dict *msg_accept(snac *snac, const xs_val *object, const char *to)
1041/* creates an Accept message (as a response to a Follow) */
1042{
1043    xs_dict *msg = msg_base(snac, "Accept", "@dummy", snac->actor, NULL, object);
1044
1045    msg = xs_dict_append(msg, "to", to);
1046
1047    return msg;
1048}
1049
1050
1051xs_dict *msg_update(snac *snac, const xs_dict *object)
1052/* creates an Update message */
1053{
1054    xs_dict *msg = msg_base(snac, "Update", "@object", snac->actor, "@now", object);
1055
1056    const char *type = xs_dict_get(object, "type");
1057
1058    if (strcmp(type, "Note") == 0) {
1059        msg = xs_dict_append(msg, "to", xs_dict_get(object, "to"));
1060        msg = xs_dict_append(msg, "cc", xs_dict_get(object, "cc"));
1061    }
1062    else
1063    if (strcmp(type, "Person") == 0) {
1064        msg = xs_dict_append(msg, "to", public_address);
1065
1066        /* also spam the people being followed, so that
1067           they have the newest information about who we are */
1068        xs *cc = following_list(snac);
1069
1070        msg = xs_dict_append(msg, "cc", cc);
1071    }
1072    else
1073        msg = xs_dict_append(msg, "to", public_address);
1074
1075    return msg;
1076}
1077
1078
1079xs_dict *msg_admiration(snac *snac, const char *object, const char *type)
1080/* creates a Like or Announce message */
1081{
1082    xs *a_msg    = NULL;
1083    xs_dict *msg = NULL;
1084    xs *wrk      = NULL;
1085
1086    /* call the object */
1087    timeline_request(snac, &object, &wrk, 0);
1088
1089    if (valid_status(object_get(object, &a_msg))) {
1090        xs *rcpts = xs_list_new();
1091        xs *o_md5 = xs_md5_hex(object, strlen(object));
1092        xs *id    = xs_fmt("%s/%s/%s", snac->actor, *type == 'L' ? "l" : "a", o_md5);
1093
1094        msg = msg_base(snac, type, id, snac->actor, "@now", object);
1095
1096        if (is_msg_public(a_msg))
1097            rcpts = xs_list_append(rcpts, public_address);
1098
1099        rcpts = xs_list_append(rcpts, get_atto(a_msg));
1100
1101        msg = xs_dict_append(msg, "to", rcpts);
1102    }
1103    else
1104        snac_log(snac, xs_fmt("msg_admiration cannot retrieve object %s", object));
1105
1106    return msg;
1107}
1108
1109
1110xs_dict *msg_repulsion(snac *user, const char *id, const char *type)
1111/* creates an Undo + admiration message */
1112{
1113    xs *a_msg    = NULL;
1114    xs_dict *msg = NULL;
1115
1116    if (valid_status(object_get(id, &a_msg))) {
1117        /* create a clone of the original admiration message */
1118        xs *object = msg_admiration(user, id, type);
1119
1120        /* delete the published date */
1121        object = xs_dict_del(object, "published");
1122
1123        /* create an undo message for this object */
1124        msg = msg_undo(user, object);
1125
1126        /* copy the 'to' field */
1127        msg = xs_dict_set(msg, "to", xs_dict_get(object, "to"));
1128    }
1129
1130    /* now we despise this */
1131    object_unadmire(id, user->actor, *type == 'L' ? 1 : 0);
1132
1133    return msg;
1134}
1135
1136
1137xs_dict *msg_actor(snac *snac)
1138/* create a Person message for this actor */
1139{
1140    xs *ctxt     = xs_list_new();
1141    xs *icon     = xs_dict_new();
1142    xs *keys     = xs_dict_new();
1143    xs *tags     = xs_list_new();
1144    xs *avtr     = NULL;
1145    xs *kid      = NULL;
1146    xs *f_bio    = NULL;
1147    xs_dict *msg = msg_base(snac, "Person", snac->actor, NULL, NULL, NULL);
1148    const char *p;
1149    int n;
1150
1151    /* change the @context (is this really necessary?) */
1152    ctxt = xs_list_append(ctxt, "https:/" "/www.w3.org/ns/activitystreams");
1153    ctxt = xs_list_append(ctxt, "https:/" "/w3id.org/security/v1");
1154    msg = xs_dict_set(msg, "@context",          ctxt);
1155
1156    msg = xs_dict_set(msg, "url",               snac->actor);
1157    msg = xs_dict_set(msg, "name",              xs_dict_get(snac->config, "name"));
1158    msg = xs_dict_set(msg, "preferredUsername", snac->uid);
1159    msg = xs_dict_set(msg, "published",         xs_dict_get(snac->config, "published"));
1160
1161    xs *f_bio_2 = not_really_markdown(xs_dict_get(snac->config, "bio"), NULL, NULL);
1162    f_bio = process_tags(snac, f_bio_2, &tags);
1163    msg = xs_dict_set(msg, "summary", f_bio);
1164    msg = xs_dict_set(msg, "tag", tags);
1165
1166    char *folders[] = { "inbox", "outbox", "followers", "following", "featured", NULL };
1167    for (n = 0; folders[n]; n++) {
1168        xs *f = xs_fmt("%s/%s", snac->actor, folders[n]);
1169        msg = xs_dict_set(msg, folders[n], f);
1170    }
1171
1172    p = xs_dict_get(snac->config, "avatar");
1173
1174    if (*p == '\0')
1175        avtr = xs_fmt("%s/susie.png", srv_baseurl);
1176    else
1177        avtr = xs_dup(p);
1178
1179    icon = xs_dict_append(icon, "type",         "Image");
1180    icon = xs_dict_append(icon, "mediaType",    xs_mime_by_ext(avtr));
1181    icon = xs_dict_append(icon, "url",          avtr);
1182    msg = xs_dict_set(msg, "icon", icon);
1183
1184    kid = xs_fmt("%s#main-key", snac->actor);
1185
1186    keys = xs_dict_append(keys, "id",           kid);
1187    keys = xs_dict_append(keys, "owner",        snac->actor);
1188    keys = xs_dict_append(keys, "publicKeyPem", xs_dict_get(snac->key, "public"));
1189    msg = xs_dict_set(msg, "publicKey", keys);
1190
1191    /* if the "bot" config field is set to true, change type to "Service" */
1192    if (xs_type(xs_dict_get(snac->config, "bot")) == XSTYPE_TRUE)
1193        msg = xs_dict_set(msg, "type", "Service");
1194
1195    /* add the header image, if there is one defined */
1196    const char *header = xs_dict_get(snac->config, "header");
1197    if (!xs_is_null(header)) {
1198        xs *d = xs_dict_new();
1199        d = xs_dict_append(d, "type",       "Image");
1200        d = xs_dict_append(d, "mediaType",  xs_mime_by_ext(header));
1201        d = xs_dict_append(d, "url",        header);
1202        msg = xs_dict_set(msg, "image", d);
1203    }
1204
1205    /* add the metadata as attachments of PropertyValue */
1206    const xs_dict *metadata = xs_dict_get(snac->config, "metadata");
1207    if (xs_type(metadata) == XSTYPE_DICT) {
1208        xs *attach = xs_list_new();
1209        const xs_str *k;
1210        const xs_str *v;
1211
1212        int c = 0;
1213        while (xs_dict_next(metadata, &k, &v, &c)) {
1214            xs *d = xs_dict_new();
1215
1216            xs *k2 = encode_html(k);
1217            xs *v2 = NULL;
1218
1219            if (xs_startswith(v, "https:/") || xs_startswith(v, "http:/")) {
1220                xs *t = encode_html(v);
1221                v2 = xs_fmt("<a href=\"%s\" rel=\"me\">%s</a>", t, t);
1222            }
1223            else
1224                v2 = encode_html(v);
1225
1226            d = xs_dict_append(d, "type",  "PropertyValue");
1227            d = xs_dict_append(d, "name",  k2);
1228            d = xs_dict_append(d, "value", v2);
1229
1230            attach = xs_list_append(attach, d);
1231        }
1232
1233        msg = xs_dict_set(msg, "attachment", attach);
1234    }
1235
1236    /* use shared inboxes? */
1237    if (xs_type(xs_dict_get(srv_config, "shared_inboxes")) == XSTYPE_TRUE) {
1238        xs *d = xs_dict_new();
1239        xs *si = xs_fmt("%s/shared-inbox", srv_baseurl);
1240        d = xs_dict_append(d, "sharedInbox", si);
1241        msg = xs_dict_set(msg, "endpoints", d);
1242    }
1243
1244    return msg;
1245}
1246
1247
1248xs_dict *msg_create(snac *snac, const xs_dict *object)
1249/* creates a 'Create' message */
1250{
1251    xs_dict *msg = msg_base(snac, "Create", "@wrapper", snac->actor, NULL, object);
1252    const xs_val *v;
1253
1254    if ((v = get_atto(object)))
1255        msg = xs_dict_append(msg, "attributedTo", v);
1256
1257    if ((v = xs_dict_get(object, "cc")))
1258        msg = xs_dict_append(msg, "cc", v);
1259
1260    if ((v = xs_dict_get(object, "to")))
1261        msg = xs_dict_append(msg, "to", v);
1262    else
1263        msg = xs_dict_append(msg, "to", public_address);
1264
1265    return msg;
1266}
1267
1268
1269xs_dict *msg_undo(snac *snac, const xs_val *object)
1270/* creates an 'Undo' message */
1271{
1272    xs_dict *msg = msg_base(snac, "Undo", "@object", snac->actor, "@now", object);
1273    const char *to;
1274
1275    if (xs_type(object) == XSTYPE_DICT && (to = xs_dict_get(object, "object")))
1276        msg = xs_dict_append(msg, "to", to);
1277
1278    return msg;
1279}
1280
1281
1282xs_dict *msg_delete(snac *snac, const char *id)
1283/* creates a 'Delete' + 'Tombstone' for a local entry */
1284{
1285    xs *tomb = xs_dict_new();
1286    xs_dict *msg = NULL;
1287
1288    /* sculpt the tombstone */
1289    tomb = xs_dict_append(tomb, "type", "Tombstone");
1290    tomb = xs_dict_append(tomb, "id",   id);
1291
1292    /* now create the Delete */
1293    msg = msg_base(snac, "Delete", "@object", snac->actor, "@now", tomb);
1294
1295    msg = xs_dict_append(msg, "to", public_address);
1296
1297    return msg;
1298}
1299
1300
1301xs_dict *msg_follow(snac *snac, const char *q)
1302/* creates a 'Follow' message */
1303{
1304    xs *actor_o = NULL;
1305    xs *actor   = NULL;
1306    xs_dict *msg = NULL;
1307    int status;
1308
1309    xs *url_or_uid = xs_strip_i(xs_str_new(q));
1310
1311    if (xs_startswith(url_or_uid, "https:/") || xs_startswith(url_or_uid, "http:/"))
1312        actor = xs_dup(url_or_uid);
1313    else
1314    if (!valid_status(webfinger_request(url_or_uid, &actor, NULL)) || actor == NULL) {
1315        snac_log(snac, xs_fmt("cannot resolve user %s to follow", url_or_uid));
1316        return NULL;
1317    }
1318
1319    /* request the actor */
1320    status = actor_request(snac, actor, &actor_o);
1321
1322    if (valid_status(status)) {
1323        /* check if the actor is an alias */
1324        const char *r_actor = xs_dict_get(actor_o, "id");
1325
1326        if (r_actor && strcmp(actor, r_actor) != 0) {
1327            snac_log(snac, xs_fmt("actor to follow is an alias %s -> %s", actor, r_actor));
1328        }
1329
1330        msg = msg_base(snac, "Follow", "@dummy", snac->actor, NULL, r_actor);
1331    }
1332    else
1333        snac_log(snac, xs_fmt("cannot get actor to follow %s %d", actor, status));
1334
1335    return msg;
1336}
1337
1338
1339xs_dict *msg_note(snac *snac, const xs_str *content, const xs_val *rcpts,
1340                  const xs_str *in_reply_to, const xs_list *attach, int priv)
1341/* creates a 'Note' message */
1342{
1343    xs *ntid = tid(0);
1344    xs *id   = xs_fmt("%s/p/%s", snac->actor, ntid);
1345    xs *ctxt = NULL;
1346    xs *fc2  = NULL;
1347    xs *fc1  = NULL;
1348    xs *to   = NULL;
1349    xs *cc   = xs_list_new();
1350    xs *irt  = NULL;
1351    xs *tag  = xs_list_new();
1352    xs *atls = xs_list_new();
1353    xs_dict *msg = msg_base(snac, "Note", id, NULL, "@now", NULL);
1354    xs_list *p;
1355    const xs_val *v;
1356
1357    if (rcpts == NULL)
1358        to = xs_list_new();
1359    else {
1360        if (xs_type(rcpts) == XSTYPE_STRING) {
1361            to = xs_list_new();
1362            to = xs_list_append(to, rcpts);
1363        }
1364        else
1365            to = xs_dup(rcpts);
1366    }
1367
1368    /* format the content */
1369    fc2 = not_really_markdown(content, &atls, &tag);
1370
1371    if (in_reply_to != NULL && *in_reply_to) {
1372        xs *p_msg = NULL;
1373        xs *wrk   = NULL;
1374
1375        /* demand this thing */
1376        timeline_request(snac, &in_reply_to, &wrk, 0);
1377
1378        if (valid_status(object_get(in_reply_to, &p_msg))) {
1379            /* add this author as recipient */
1380            const char *a, *v;
1381
1382            if ((a = get_atto(p_msg)) && xs_list_in(to, a) == -1)
1383                to = xs_list_append(to, a);
1384
1385            /* add this author to the tag list as a mention */
1386            if (!xs_is_null(a)) {
1387                xs *l = xs_split(a, "/");
1388                xs *actor_o = NULL;
1389
1390                if (xs_list_len(l) > 3 && valid_status(object_get(a, &actor_o))) {
1391                    const char *uname = xs_dict_get(actor_o, "preferredUsername");
1392
1393                    if (!xs_is_null(uname) && *uname) {
1394                        xs *handle = xs_fmt("@%s@%s", uname, xs_list_get(l, 2));
1395
1396                        xs *t = xs_dict_new();
1397
1398                        t = xs_dict_append(t, "type", "Mention");
1399                        t = xs_dict_append(t, "href", a);
1400                        t = xs_dict_append(t, "name", handle);
1401
1402                        tag = xs_list_append(tag, t);
1403                    }
1404                }
1405            }
1406
1407            /* get the context, if there is one */
1408            if ((v = xs_dict_get(p_msg, "context")))
1409                ctxt = xs_dup(v);
1410
1411            /* propagate the conversation field, if there is one */
1412            if ((v = xs_dict_get(p_msg, "conversation")))
1413                msg = xs_dict_append(msg, "conversation", v);
1414
1415            /* if this message is public, ours will also be */
1416            if (!priv && is_msg_public(p_msg) && xs_list_in(to, public_address) == -1)
1417                to = xs_list_append(to, public_address);
1418        }
1419
1420        irt = xs_dup(in_reply_to);
1421    }
1422    else
1423        irt = xs_val_new(XSTYPE_NULL);
1424
1425    /* extract the mentions and hashtags and convert the content */
1426    fc1 = process_tags(snac, fc2, &tag);
1427
1428    /* create the attachment list, if there are any */
1429    if (!xs_is_null(attach)) {
1430        int c = 0;
1431        while (xs_list_next(attach, &v, &c)) {
1432            xs *d            = xs_dict_new();
1433            const char *url  = xs_list_get(v, 0);
1434            const char *alt  = xs_list_get(v, 1);
1435            const char *mime = xs_mime_by_ext(url);
1436
1437            d = xs_dict_append(d, "mediaType", mime);
1438            d = xs_dict_append(d, "url",       url);
1439            d = xs_dict_append(d, "name",      alt);
1440            d = xs_dict_append(d, "type",
1441                xs_startswith(mime, "image/") ? "Image" : "Document");
1442
1443            atls = xs_list_append(atls, d);
1444        }
1445    }
1446
1447    if (ctxt == NULL)
1448        ctxt = xs_fmt("%s#ctxt", id);
1449
1450    /* add all mentions to the cc */
1451    p = tag;
1452    while (xs_list_iter(&p, &v)) {
1453        if (xs_type(v) == XSTYPE_DICT) {
1454            const char *t;
1455
1456            if (!xs_is_null(t = xs_dict_get(v, "type")) && strcmp(t, "Mention") == 0) {
1457                if (!xs_is_null(t = xs_dict_get(v, "href")))
1458                    cc = xs_list_append(cc, t);
1459            }
1460        }
1461    }
1462
1463    /* no recipients? must be for everybody */
1464    if (!priv && xs_list_len(to) == 0)
1465        to = xs_list_append(to, public_address);
1466
1467    /* delete all cc recipients that also are in the to */
1468    p = to;
1469    while (xs_list_iter(&p, &v)) {
1470        int i;
1471
1472        if ((i = xs_list_in(cc, v)) != -1)
1473            cc = xs_list_del(cc, i);
1474    }
1475
1476    msg = xs_dict_append(msg, "attributedTo", snac->actor);
1477    msg = xs_dict_append(msg, "summary",      "");
1478    msg = xs_dict_append(msg, "content",      fc1);
1479    msg = xs_dict_append(msg, "context",      ctxt);
1480    msg = xs_dict_append(msg, "url",          id);
1481    msg = xs_dict_append(msg, "to",           to);
1482    msg = xs_dict_append(msg, "cc",           cc);
1483    msg = xs_dict_append(msg, "inReplyTo",    irt);
1484    msg = xs_dict_append(msg, "tag",          tag);
1485
1486    msg = xs_dict_append(msg, "sourceContent", content);
1487
1488    if (xs_list_len(atls))
1489        msg = xs_dict_append(msg, "attachment", atls);
1490
1491    return msg;
1492}
1493
1494
1495xs_dict *msg_ping(snac *user, const char *rcpt)
1496/* creates a Ping message (https://humungus.tedunangst.com/r/honk/v/tip/f/docs/ping.txt) */
1497{
1498    xs_dict *msg = msg_base(user, "Ping", "@dummy", user->actor, NULL, NULL);
1499
1500    msg = xs_dict_append(msg, "to", rcpt);
1501
1502    return msg;
1503}
1504
1505
1506xs_dict *msg_pong(snac *user, const char *rcpt, const char *object)
1507/* creates a Pong message (https://humungus.tedunangst.com/r/honk/v/tip/f/docs/ping.txt) */
1508{
1509    xs_dict *msg = msg_base(user, "Pong", "@dummy", user->actor, NULL, object);
1510
1511    msg = xs_dict_append(msg, "to", rcpt);
1512
1513    return msg;
1514}
1515
1516
1517xs_dict *msg_question(snac *user, const char *content, xs_list *attach,
1518                      const xs_list *opts, int multiple, int end_secs)
1519/* creates a Question message */
1520{
1521    xs_dict *msg = msg_note(user, content, NULL, NULL, attach, 0);
1522    int max      = 8;
1523    xs_set seen;
1524
1525    msg = xs_dict_set(msg, "type", "Question");
1526
1527    /* make it non-editable */
1528    msg = xs_dict_del(msg, "sourceContent");
1529
1530    xs *o = xs_list_new();
1531    xs_list *p = (xs_list *)opts;
1532    const xs_str *v;
1533    xs *replies = xs_json_loads("{\"type\":\"Collection\",\"totalItems\":0}");
1534
1535    xs_set_init(&seen);
1536
1537    while (max && xs_list_iter(&p, &v)) {
1538        if (*v) {
1539            xs *v2 = xs_dup(v);
1540            xs *d  = xs_dict_new();
1541
1542            if (strlen(v2) > 60) {
1543                v2[60] = '\0';
1544                v2 = xs_str_cat(v2, "...");
1545            }
1546
1547            if (xs_set_add(&seen, v2) == 1) {
1548                d = xs_dict_append(d, "type",    "Note");
1549                d = xs_dict_append(d, "name",    v2);
1550                d = xs_dict_append(d, "replies", replies);
1551                o = xs_list_append(o, d);
1552
1553                max--;
1554            }
1555        }
1556    }
1557
1558    xs_set_free(&seen);
1559
1560    msg = xs_dict_append(msg, multiple ? "anyOf" : "oneOf", o);
1561
1562    /* set the end time */
1563    time_t t = time(NULL) + end_secs;
1564    xs *et = xs_str_utctime(t, ISO_DATE_SPEC);
1565
1566    msg = xs_dict_append(msg, "endTime", et);
1567
1568    return msg;
1569}
1570
1571
1572int update_question(snac *user, const char *id)
1573/* updates the poll counts */
1574{
1575    xs *msg   = NULL;
1576    xs *rcnt  = xs_dict_new();
1577    xs *lopts = xs_list_new();
1578    const xs_list *opts;
1579    xs_list *p;
1580    const xs_val *v;
1581
1582    /* get the object */
1583    if (!valid_status(object_get(id, &msg)))
1584        return -1;
1585
1586    /* closed? do nothing more */
1587    if (xs_dict_get(msg, "closed"))
1588        return -2;
1589
1590    /* get the options */
1591    if ((opts = xs_dict_get(msg, "oneOf")) == NULL &&
1592        (opts = xs_dict_get(msg, "anyOf")) == NULL)
1593        return -3;
1594
1595    /* fill the initial count */
1596    int c = 0;
1597    while (xs_list_next(opts, &v, &c)) {
1598        const char *name = xs_dict_get(v, "name");
1599        if (name) {
1600            lopts = xs_list_append(lopts, name);
1601            rcnt  = xs_dict_set(rcnt, name, xs_stock(0));
1602        }
1603    }
1604
1605    xs_set s;
1606    xs_set_init(&s);
1607
1608    /* iterate now the children (the votes) */
1609    xs *chld = object_children(id);
1610    p = chld;
1611    while (xs_list_iter(&p, &v)) {
1612        xs *obj = NULL;
1613
1614        if (!valid_status(object_get_by_md5(v, &obj)))
1615            continue;
1616
1617        const char *name = xs_dict_get(obj, "name");
1618        const char *atto = get_atto(obj);
1619
1620        if (name && atto) {
1621            /* get the current count */
1622            const xs_number *cnt = xs_dict_get(rcnt, name);
1623
1624            if (xs_type(cnt) == XSTYPE_NUMBER) {
1625                /* if it exists, increment */
1626                xs *ucnt = xs_number_new(xs_number_get(cnt) + 1);
1627                rcnt = xs_dict_set(rcnt, name, ucnt);
1628
1629                xs_set_add(&s, atto);
1630            }
1631        }
1632    }
1633
1634    xs *rcpts = xs_set_result(&s);
1635
1636    /* create a new list of options with their new counts */
1637    xs *nopts = xs_list_new();
1638    p = lopts;
1639    while (xs_list_iter(&p, &v)) {
1640        const xs_number *cnt = xs_dict_get(rcnt, v);
1641
1642        if (xs_type(cnt) == XSTYPE_NUMBER) {
1643            xs *d1 = xs_dict_new();
1644            xs *d2 = xs_dict_new();
1645
1646            d2 = xs_dict_append(d2, "type",       "Collection");
1647            d2 = xs_dict_append(d2, "totalItems", cnt);
1648
1649            d1 = xs_dict_append(d1, "type",    "Note");
1650            d1 = xs_dict_append(d1, "name",    v);
1651            d1 = xs_dict_append(d1, "replies", d2);
1652
1653            nopts = xs_list_append(nopts, d1);
1654        }
1655    }
1656
1657    /* update the list */
1658    msg = xs_dict_set(msg, xs_dict_get(msg, "oneOf") != NULL ? "oneOf" : "anyOf", nopts);
1659
1660    /* due date? */
1661    int closed = 0;
1662    const char *end_time = xs_dict_get(msg, "endTime");
1663    if (!xs_is_null(end_time)) {
1664        xs *now = xs_str_utctime(0, ISO_DATE_SPEC);
1665
1666        /* is now greater than the endTime? */
1667        if (strcmp(now, end_time) >= 0) {
1668            xs *et    = xs_dup(end_time);
1669            msg       = xs_dict_set(msg, "closed", et);
1670
1671            closed = 1;
1672        }
1673    }
1674
1675    /* update the count of voters */
1676    xs *vcnt = xs_number_new(xs_list_len(rcpts));
1677    msg = xs_dict_set(msg, "votersCount", vcnt);
1678    msg = xs_dict_set(msg, "cc", rcpts);
1679
1680    /* store */
1681    object_add_ow(id, msg);
1682
1683    snac_debug(user, 1, xs_fmt("recounted poll %s", id));
1684    timeline_touch(user);
1685
1686    /* send an update message to all voters */
1687    xs *u_msg = msg_update(user, msg);
1688    u_msg = xs_dict_set(u_msg, "cc", rcpts);
1689
1690    enqueue_message(user, u_msg);
1691
1692    if (closed) {
1693        xs *c_msg = msg_update(user, msg);
1694        notify(user, "Update", "Question", user->actor, c_msg);
1695    }
1696
1697    return 0;
1698}
1699
1700
1701/** queues **/
1702
1703int process_input_message(snac *snac, const xs_dict *msg, const xs_dict *req)
1704/* processes an ActivityPub message from the input queue */
1705/* return values: -1, fatal error; 0, transient error, retry;
1706   1, processed and done; 2, propagate to users (only when no user is set) */
1707{
1708    const char *actor = xs_dict_get(msg, "actor");
1709    const char *type  = xs_dict_get(msg, "type");
1710    xs *actor_o = NULL;
1711    int a_status;
1712    int do_notify = 0;
1713
1714    if (xs_is_null(actor) || *actor == '\0') {
1715        srv_debug(0, xs_fmt("malformed message (bad actor)"));
1716        return -1;
1717    }
1718
1719    /* question votes may not have a type */
1720    if (xs_is_null(type))
1721        type = "Note";
1722
1723    /* reject uninteresting messages right now */
1724    if (xs_match(type, "Add|View|Reject|Read|Remove")) {
1725        srv_debug(0, xs_fmt("Ignored message of type '%s'", type));
1726        return -1;
1727    }
1728
1729    const char *object, *utype;
1730
1731    object = xs_dict_get(msg, "object");
1732    if (object != NULL && xs_type(object) == XSTYPE_DICT)
1733        utype = xs_dict_get(object, "type");
1734    else
1735        utype = "(null)";
1736
1737    /* special case for Delete messages */
1738    if (strcmp(type, "Delete") == 0) {
1739        /* if the actor is not here, do not even try */
1740        if (!object_here(actor)) {
1741            srv_debug(1, xs_fmt("dropped 'Delete' message from unknown actor '%s'", actor));
1742            return -1;
1743        }
1744
1745        /* discard crap */
1746        if (xs_is_null(object)) {
1747            srv_log(xs_fmt("dropped 'Delete' message with invalid object from actor '%s'", actor));
1748            return -1;
1749        }
1750
1751        /* also discard if the object to be deleted is not here */
1752        const char *obj_id = object;
1753        if (xs_type(obj_id) == XSTYPE_DICT)
1754            obj_id = xs_dict_get(obj_id, "id");
1755
1756        if (!object_here(obj_id)) {
1757            srv_debug(1, xs_fmt("dropped 'Delete' message from unknown object '%s'", obj_id));
1758            return -1;
1759        }
1760    }
1761
1762    /* bring the actor */
1763    a_status = actor_request(snac, actor, &actor_o);
1764
1765    /* do not retry permanent failures */
1766    if (a_status == HTTP_STATUS_NOT_FOUND
1767        || a_status == HTTP_STATUS_GONE
1768        || a_status < 0) {
1769        srv_debug(1, xs_fmt("dropping message due to actor error %s %d", actor, a_status));
1770        return -1;
1771    }
1772
1773    if (!valid_status(a_status)) {
1774        /* do not retry 'Delete' messages */
1775        if (strcmp(type, "Delete") == 0) {
1776            srv_debug(1, xs_fmt("dropping 'Delete' message due to actor error %s %d", actor, a_status));
1777            return -1;
1778        }
1779
1780        /* other actor download errors */
1781
1782        /* the actor may require a signed request; propagate if no user is set */
1783        if (snac == NULL)
1784            return 2;
1785
1786        /* may need a retry */
1787        srv_debug(0, xs_fmt("error requesting actor %s %d -- retry later", actor, a_status));
1788        return 0;
1789    }
1790
1791    /* check the signature */
1792    xs *sig_err = NULL;
1793
1794    if (!check_signature(req, &sig_err)) {
1795        srv_log(xs_fmt("bad signature %s (%s)", actor, sig_err));
1796
1797        srv_archive_error("check_signature", sig_err, req, msg);
1798        return -1;
1799    }
1800
1801    /* if no user is set, no further checks can be done; propagate */
1802    if (snac == NULL)
1803        return 2;
1804
1805    /* reject messages that are not for this user */
1806    if (!is_msg_for_me(snac, msg)) {
1807        snac_debug(snac, 1, xs_fmt("message from %s of type '%s' not for us", actor, type));
1808
1809        return 1;
1810    }
1811
1812    /* if it's a DM from someone we don't follow, reject the message */
1813    if (xs_type(xs_dict_get(snac->config, "drop_dm_from_unknown")) == XSTYPE_TRUE) {
1814        if (strcmp(utype, "Note") == 0 && !is_msg_public(msg) &&
1815            !following_check(snac, actor)) {
1816            snac_log(snac, xs_fmt("DM rejected from unknown actor %s", actor));
1817
1818            return 1;
1819        }
1820    }
1821
1822    /* check the minimum acceptable account age */
1823    int min_account_age = xs_number_get(xs_dict_get(srv_config, "min_account_age"));
1824
1825    if (min_account_age > 0) {
1826        const char *actor_date = xs_dict_get(actor_o, "published");
1827        if (!xs_is_null(actor_date)) {
1828            time_t actor_t = xs_parse_iso_date(actor_date, 0);
1829
1830            if (actor_t < 950000000) {
1831                snac_log(snac, xs_fmt("rejected activity from %s (suspicious date, %s)",
1832                    actor, actor_date));
1833
1834                return 1;
1835            }
1836
1837            if (actor_t > 0) {
1838                int td = (int)(time(NULL) - actor_t);
1839
1840                snac_debug(snac, 2, xs_fmt("actor %s age: %d seconds", actor, td));
1841
1842                if (td < min_account_age) {
1843                    snac_log(snac, xs_fmt("rejected activity from %s (too new, %d seconds)",
1844                        actor, td));
1845
1846                    return 1;
1847                }
1848            }
1849        }
1850        else
1851            snac_debug(snac, 1, xs_fmt("warning: empty or null creation date for %s", actor));
1852    }
1853
1854    if (strcmp(type, "Follow") == 0) { /** **/
1855        if (!follower_check(snac, actor)) {
1856            /* ensure the actor object is here */
1857            if (!object_here(actor)) {
1858                xs *actor_obj = NULL;
1859                actor_request(snac, actor, &actor_obj);
1860                object_add(actor, actor_obj);
1861            }
1862
1863            xs *f_msg = xs_dup(msg);
1864            xs *reply = msg_accept(snac, f_msg, actor);
1865
1866            post_message(snac, actor, reply);
1867
1868            if (xs_is_null(xs_dict_get(f_msg, "published"))) {
1869                /* add a date if it doesn't include one (Mastodon) */
1870                xs *date = xs_str_utctime(0, ISO_DATE_SPEC);
1871                f_msg = xs_dict_set(f_msg, "published", date);
1872            }
1873
1874            timeline_add(snac, xs_dict_get(f_msg, "id"), f_msg);
1875
1876            follower_add(snac, actor);
1877
1878            snac_log(snac, xs_fmt("new follower %s", actor));
1879            do_notify = 1;
1880        }
1881        else
1882            snac_log(snac, xs_fmt("repeated 'Follow' from %s", actor));
1883    }
1884    else
1885    if (strcmp(type, "Undo") == 0) { /** **/
1886        const char *id = xs_dict_get(object, "object");
1887
1888        if (xs_type(object) != XSTYPE_DICT)
1889            utype = "Follow";
1890
1891        if (strcmp(utype, "Follow") == 0) { /** **/
1892            if (id && strcmp(id, snac->actor) != 0)
1893                snac_debug(snac, 1, xs_fmt("Undo + Follow from %s not for us (%s)", actor, id));
1894            else {
1895                if (valid_status(follower_del(snac, actor))) {
1896                    snac_log(snac, xs_fmt("no longer following us %s", actor));
1897                    do_notify = 1;
1898                }
1899                else
1900                    snac_log(snac, xs_fmt("error deleting follower %s", actor));
1901            }
1902        }
1903        else
1904        if (strcmp(utype, "Like") == 0 || strcmp(utype, "EmojiReact") == 0) { /** **/
1905            int status = object_unadmire(id, actor, 1);
1906
1907            snac_log(snac, xs_fmt("Undo '%s' for %s %d", utype, id, status));
1908        }
1909        else
1910        if (strcmp(utype, "Announce") == 0) { /** **/
1911            int status = HTTP_STATUS_OK;
1912
1913            /* commented out: if a followed user boosts something that
1914               is requested and then unboosts, the post remains here,
1915               but with no apparent reason, and that is confusing */
1916            //status = object_unadmire(id, actor, 0);
1917
1918            snac_log(snac, xs_fmt("Unboost for %s %d", id, status));
1919        }
1920        else
1921            snac_debug(snac, 1, xs_fmt("ignored 'Undo' for object type '%s'", utype));
1922    }
1923    else
1924    if (strcmp(type, "Create") == 0) { /** **/
1925        if (is_muted(snac, actor)) {
1926            snac_log(snac, xs_fmt("ignored 'Create' + '%s' from muted actor %s", utype, actor));
1927            return 1;
1928        }
1929
1930        if (xs_match(utype, "Note|Article")) { /** **/
1931            const char *id          = xs_dict_get(object, "id");
1932            const char *in_reply_to = xs_dict_get(object, "inReplyTo");
1933            const char *atto        = get_atto(object);
1934            xs *wrk           = NULL;
1935
1936            if (xs_is_null(id))
1937                snac_log(snac, xs_fmt("malformed message: no 'id' field"));
1938            else
1939            if (xs_is_null(atto))
1940                snac_log(snac, xs_fmt("malformed message: no 'attributedTo' field"));
1941            else
1942            if (!xs_is_null(in_reply_to) && is_hidden(snac, in_reply_to)) {
1943                snac_debug(snac, 0, xs_fmt("dropped reply %s to hidden post %s", id, in_reply_to));
1944            }
1945            else {
1946                if (content_match("filter_reject.txt", object)) {
1947                    snac_log(snac, xs_fmt("rejected by content %s", id));
1948                    return 1;
1949                }
1950
1951                if (strcmp(actor, atto) != 0)
1952                    snac_log(snac, xs_fmt("SUSPICIOUS: actor != atto (%s != %s)", actor, atto));
1953
1954                timeline_request(snac, &in_reply_to, &wrk, 0);
1955
1956                if (timeline_add(snac, id, object)) {
1957                    snac_log(snac, xs_fmt("new '%s' %s %s", utype, actor, id));
1958                    do_notify = 1;
1959                }
1960
1961                /* if it has a "name" field, it may be a vote for a question */
1962                const char *name = xs_dict_get(object, "name");
1963
1964                if (!xs_is_null(name) && *name && !xs_is_null(in_reply_to) && *in_reply_to)
1965                    update_question(snac, in_reply_to);
1966            }
1967        }
1968        else
1969        if (strcmp(utype, "Question") == 0) { /**  **/
1970            const char *id = xs_dict_get(object, "id");
1971
1972            if (timeline_add(snac, id, object))
1973                snac_log(snac, xs_fmt("new 'Question' %s %s", actor, id));
1974        }
1975        else
1976        if (strcmp(utype, "Video") == 0) { /** **/
1977            const char *id = xs_dict_get(object, "id");
1978
1979            if (timeline_add(snac, id, object))
1980                snac_log(snac, xs_fmt("new 'Video' %s %s", actor, id));
1981        }
1982        else
1983            snac_debug(snac, 1, xs_fmt("ignored 'Create' for object type '%s'", utype));
1984    }
1985    else
1986    if (strcmp(type, "Accept") == 0) { /** **/
1987        if (strcmp(utype, "(null)") == 0) {
1988            const char *obj_id = xs_dict_get(msg, "object");
1989
1990            /* if the accepted object id is a string that may
1991               be created by us, it's a follow */
1992            if (xs_type(obj_id) == XSTYPE_STRING &&
1993                xs_startswith(obj_id, srv_baseurl) &&
1994                xs_endswith(obj_id, "/Follow"))
1995                utype = "Follow";
1996        }
1997
1998        if (strcmp(utype, "Follow") == 0) { /** **/
1999            if (following_check(snac, actor)) {
2000                following_add(snac, actor, msg);
2001                snac_log(snac, xs_fmt("confirmed follow from %s", actor));
2002            }
2003            else
2004                snac_log(snac, xs_fmt("spurious follow accept from %s", actor));
2005        }
2006        else
2007        if (strcmp(utype, "Create") == 0) {
2008            /* some implementations send Create confirmations, go figure */
2009            snac_debug(snac, 1, xs_dup("ignored 'Accept' + 'Create'"));
2010        }
2011        else {
2012            srv_archive_error("accept", "ignored Accept", req, msg);
2013            snac_debug(snac, 1, xs_fmt("ignored 'Accept' for object type '%s'", utype));
2014        }
2015    }
2016    else
2017    if (strcmp(type, "Like") == 0 || strcmp(type, "EmojiReact") == 0) { /** **/
2018        if (xs_type(object) == XSTYPE_DICT)
2019            object = xs_dict_get(object, "id");
2020
2021        if (timeline_admire(snac, object, actor, 1) == HTTP_STATUS_CREATED)
2022            snac_log(snac, xs_fmt("new '%s' %s %s", type, actor, object));
2023        else
2024            snac_log(snac, xs_fmt("repeated 'Like' from %s to %s", actor, object));
2025
2026        do_notify = 1;
2027    }
2028    else
2029    if (strcmp(type, "Announce") == 0) { /** **/
2030        if (xs_type(object) == XSTYPE_DICT)
2031            object = xs_dict_get(object, "id");
2032
2033        if (is_muted(snac, actor) && !xs_startswith(object, snac->actor))
2034            snac_log(snac, xs_fmt("dropped 'Announce' from muted actor %s", actor));
2035        else
2036        if (is_limited(snac, actor) && !xs_startswith(object, snac->actor))
2037            snac_log(snac, xs_fmt("dropped 'Announce' from limited actor %s", actor));
2038        else {
2039            xs *a_msg = NULL;
2040            xs *wrk   = NULL;
2041
2042            timeline_request(snac, &object, &wrk, 0);
2043
2044            if (valid_status(object_get(object, &a_msg))) {
2045                const char *who = get_atto(a_msg);
2046
2047                if (who && !is_muted(snac, who)) {
2048                    /* bring the actor */
2049                    xs *who_o = NULL;
2050
2051                    if (valid_status(actor_request(snac, who, &who_o))) {
2052                        if (timeline_admire(snac, object, actor, 0) == HTTP_STATUS_CREATED)
2053                            snac_log(snac, xs_fmt("new 'Announce' %s %s", actor, object));
2054                        else
2055                            snac_log(snac, xs_fmt("repeated 'Announce' from %s to %s",
2056                                actor, object));
2057
2058                        /* distribute the post with the actor as 'proxy' */
2059                        list_distribute(snac, actor, a_msg);
2060
2061                        do_notify = 1;
2062                    }
2063                    else
2064                        snac_debug(snac, 1, xs_fmt("dropped 'Announce' on actor request error %s", who));
2065                }
2066                else
2067                    snac_log(snac, xs_fmt("ignored 'Announce' about muted actor %s", who));
2068            }
2069            else
2070                snac_debug(snac, 2, xs_fmt("error requesting 'Announce' object %s", object));
2071        }
2072    }
2073    else
2074    if (strcmp(type, "Update") == 0) { /** **/
2075        if (xs_match(utype, "Person|Service")) { /** **/
2076            actor_add(actor, xs_dict_get(msg, "object"));
2077            timeline_touch(snac);
2078
2079            snac_log(snac, xs_fmt("updated actor %s", actor));
2080        }
2081        else
2082        if (xs_match(utype, "Note|Page|Article|Video")) { /** **/
2083            const char *id = xs_dict_get(object, "id");
2084
2085            if (object_here(id)) {
2086                object_add_ow(id, object);
2087                timeline_touch(snac);
2088
2089                snac_log(snac, xs_fmt("updated '%s' %s", utype, id));
2090            }
2091            else
2092                snac_log(snac, xs_fmt("dropped update for unknown '%s' %s", utype, id));
2093        }
2094        else
2095        if (strcmp(utype, "Question") == 0) { /** **/
2096            const char *id     = xs_dict_get(object, "id");
2097            const char *closed = xs_dict_get(object, "closed");
2098
2099            object_add_ow(id, object);
2100            timeline_touch(snac);
2101
2102            snac_log(snac, xs_fmt("%s poll %s", closed == NULL ? "updated" : "closed", id));
2103
2104            if (closed != NULL)
2105                do_notify = 1;
2106        }
2107        else {
2108            srv_archive_error("unsupported_update", "unsupported_update", req, msg);
2109
2110            snac_log(snac, xs_fmt("ignored 'Update' for object type '%s'", utype));
2111        }
2112    }
2113    else
2114    if (strcmp(type, "Delete") == 0) { /** **/
2115        if (xs_type(object) == XSTYPE_DICT)
2116            object = xs_dict_get(object, "id");
2117
2118        if (object_here(object)) {
2119            timeline_del(snac, object);
2120            snac_debug(snac, 1, xs_fmt("new 'Delete' %s %s", actor, object));
2121        }
2122        else
2123            snac_debug(snac, 1, xs_fmt("ignored 'Delete' for unknown object %s", object));
2124    }
2125    else
2126    if (strcmp(type, "Pong") == 0) { /** **/
2127        snac_log(snac, xs_fmt("'Pong' received from %s", actor));
2128    }
2129    else
2130    if (strcmp(type, "Ping") == 0) { /** **/
2131        snac_log(snac, xs_fmt("'Ping' requested from %s", actor));
2132
2133        xs *rsp = msg_pong(snac, actor, xs_dict_get(msg, "id"));
2134
2135        enqueue_output_by_actor(snac, rsp, actor, 0);
2136    }
2137    else
2138    if (strcmp(type, "Block") == 0) { /** **/
2139        snac_log(snac, xs_fmt("'Block' received from %s", actor));
2140
2141        /* should we MUTE the actor back? */
2142        /* mute(snac, actor); */
2143
2144        do_notify = 1;
2145    }
2146    else
2147    if (strcmp(type, "Move") == 0) { /** **/
2148        do_notify = 1;
2149
2150        const char *old_account = xs_dict_get(msg, "object");
2151        const char *new_account = xs_dict_get(msg, "target");
2152
2153        if (!xs_is_null(old_account) && !xs_is_null(new_account)) {
2154            if (following_check(snac, old_account)) {
2155                xs *n_actor = NULL;
2156
2157                if (valid_status(object_get(new_account, &n_actor))) {
2158                    const xs_list *aka = xs_dict_get(n_actor, "alsoKnownAs");
2159
2160                    if (xs_type(aka) == XSTYPE_LIST) {
2161                        if (xs_list_in(aka, old_account) != -1) {
2162                            /* all conditions met! */
2163
2164                            /* follow new account */
2165                            xs *f_msg = msg_follow(snac, new_account);
2166
2167                            if (f_msg != NULL) {
2168                                const char *new_actor = xs_dict_get(f_msg, "object");
2169                                following_add(snac, new_actor, f_msg);
2170                                enqueue_output_by_actor(snac, f_msg, new_actor, 0);
2171
2172                                snac_log(snac, xs_fmt("'Move': following %s", new_account));
2173                            }
2174
2175                            /* unfollow old account */
2176                            xs *of_msg = NULL;
2177
2178                            if (valid_status(following_get(snac, old_account, &of_msg))) {
2179                                xs *uf_msg = msg_undo(snac, xs_dict_get(of_msg, "object"));
2180                                following_del(snac, old_account);
2181                                enqueue_output_by_actor(snac, uf_msg, old_account, 0);
2182
2183                                snac_log(snac, xs_fmt("'Move': unfollowing %s", old_account));
2184                            }
2185                        }
2186                        else
2187                            snac_log(snac, xs_fmt("'Move' error: old actor %s not found in %s 'alsoKnownAs'",
2188                                old_account, new_account));
2189                    }
2190                    else
2191                        snac_log(snac, xs_fmt("'Move' error: cannot get %s 'alsoKnownAs'", new_account));
2192                }
2193                else
2194                    snac_log(snac, xs_fmt("'Move' error: cannot get new actor %s", new_account));
2195            }
2196            else
2197                snac_log(snac, xs_fmt("'Move' error: actor %s is not being followed", old_account));
2198        }
2199        else {
2200            snac_log(snac, xs_fmt("'Move' error: malformed message from %s", actor));
2201            srv_archive_error("move", "move", req, msg);
2202        }
2203    }
2204    else {
2205        srv_archive_error("unsupported_type", "unsupported_type", req, msg);
2206
2207        snac_debug(snac, 1, xs_fmt("process_input_message type '%s' ignored", type));
2208    }
2209
2210    if (do_notify) {
2211        notify(snac, type, utype, actor, msg);
2212
2213        timeline_touch(snac);
2214    }
2215
2216    return 1;
2217}
2218
2219
2220int send_email(const char *msg)
2221/* invoke sendmail with email headers and body in msg */
2222{
2223    FILE *f;
2224    int status;
2225    int fds[2];
2226    pid_t pid;
2227    if (pipe(fds) == -1) return -1;
2228    pid = vfork();
2229    if (pid == -1) return -1;
2230    else if (pid == 0) {
2231        dup2(fds[0], 0);
2232        close(fds[0]);
2233        close(fds[1]);
2234        execl("/usr/sbin/sendmail", "sendmail", "-t", (char *) NULL);
2235        _exit(1);
2236    }
2237    close(fds[0]);
2238    if ((f = fdopen(fds[1], "w")) == NULL) {
2239        close(fds[1]);
2240        return -1;
2241    }
2242    fprintf(f, "%s\n", msg);
2243    fclose(f);
2244    if (waitpid(pid, &status, 0) == -1) return -1;
2245    return status;
2246}
2247
2248
2249void process_user_queue_item(snac *snac, xs_dict *q_item)
2250/* processes an item from the user queue */
2251{
2252    const char *type;
2253    int queue_retry_max = xs_number_get(xs_dict_get(srv_config, "queue_retry_max"));
2254
2255    if ((type = xs_dict_get(q_item, "type")) == NULL)
2256        type = "output";
2257
2258    if (strcmp(type, "message") == 0) {
2259        const xs_dict *msg = xs_dict_get(q_item, "message");
2260        xs *rcpts = recipient_list(snac, msg, 1);
2261        xs_set inboxes;
2262        const xs_str *actor;
2263        int c;
2264
2265        xs_set_init(&inboxes);
2266
2267        /* iterate the recipients */
2268        c = 0;
2269        while (xs_list_next(rcpts, &actor, &c)) {
2270            xs *inbox = get_actor_inbox(actor);
2271
2272            if (inbox != NULL) {
2273                /* add to the set and, if it's not there, send message */
2274                if (xs_set_add(&inboxes, inbox) == 1)
2275                    enqueue_output(snac, msg, inbox, 0, 0);
2276            }
2277            else
2278                snac_log(snac, xs_fmt("cannot find inbox for %s", actor));
2279        }
2280
2281        /* if it's a public note or question, send to the collected inboxes */
2282        if (xs_match(xs_dict_get_def(msg, "type", ""), "Create|Update") && is_msg_public(msg)) {
2283            if (xs_type(xs_dict_get(srv_config, "disable_inbox_collection")) != XSTYPE_TRUE) {
2284                xs *shibx = inbox_list();
2285                const xs_str *inbox;
2286
2287                c = 0;
2288                while (xs_list_next(shibx, &inbox, &c)) {
2289                    if (xs_set_add(&inboxes, inbox) == 1)
2290                        enqueue_output(snac, msg, inbox, 0, 0);
2291                }
2292            }
2293        }
2294
2295        xs_set_free(&inboxes);
2296    }
2297    else
2298    if (strcmp(type, "input") == 0) {
2299        /* process the message */
2300        const xs_dict *msg = xs_dict_get(q_item, "message");
2301        const xs_dict *req = xs_dict_get(q_item, "req");
2302        int retries  = xs_number_get(xs_dict_get(q_item, "retries"));
2303
2304        if (xs_is_null(msg))
2305            return;
2306
2307        if (!process_input_message(snac, msg, req)) {
2308            if (retries > queue_retry_max)
2309                snac_log(snac, xs_fmt("input giving up"));
2310            else {
2311                /* reenqueue */
2312                enqueue_input(snac, msg, req, retries + 1);
2313                snac_log(snac, xs_fmt("input requeue #%d", retries + 1));
2314            }
2315        }
2316    }
2317    else
2318    if (strcmp(type, "close_question") == 0) {
2319        /* the time for this question has ended */
2320        const char *id = xs_dict_get(q_item, "message");
2321
2322        if (!xs_is_null(id))
2323            update_question(snac, id);
2324    }
2325    else
2326    if (strcmp(type, "object_request") == 0) {
2327        const char *id = xs_dict_get(q_item, "message");
2328
2329        if (!xs_is_null(id)) {
2330            int status;
2331            xs *data = NULL;
2332
2333            status = activitypub_request(snac, id, &data);
2334
2335            if (valid_status(status))
2336                object_add_ow(id, data);
2337
2338            snac_debug(snac, 1, xs_fmt("object_request %s %d", id, status));
2339        }
2340    }
2341    else
2342    if (strcmp(type, "verify_links") == 0) {
2343        verify_links(snac);
2344    }
2345    else
2346    if (strcmp(type, "actor_refresh") == 0) {
2347        const char *actor = xs_dict_get(q_item, "actor");
2348        double mtime = object_mtime(actor);
2349
2350        /* only refresh if it was refreshed more than an hour ago */
2351        if (mtime + 3600.0 < (double) time(NULL)) {
2352            xs *actor_o = NULL;
2353            int status;
2354
2355            if (valid_status((status = activitypub_request(snac, actor, &actor_o))))
2356                actor_add(actor, actor_o);
2357            else
2358                object_touch(actor);
2359
2360            snac_log(snac, xs_fmt("actor_refresh %s %d", actor, status));
2361        }
2362    }
2363    else
2364        snac_log(snac, xs_fmt("unexpected user q_item type '%s'", type));
2365}
2366
2367
2368int process_user_queue(snac *snac)
2369/* processes a user's queue */
2370{
2371    int cnt = 0;
2372    xs *list = user_queue(snac);
2373
2374    xs_list *p = list;
2375    const xs_str *fn;
2376
2377    while (xs_list_iter(&p, &fn)) {
2378        xs *q_item = dequeue(fn);
2379
2380        if (q_item == NULL)
2381            continue;
2382
2383        process_user_queue_item(snac, q_item);
2384        cnt++;
2385    }
2386
2387    return cnt;
2388}
2389
2390
2391void process_queue_item(xs_dict *q_item)
2392/* processes an item from the global queue */
2393{
2394    const char *type = xs_dict_get(q_item, "type");
2395    int queue_retry_max = xs_number_get(xs_dict_get(srv_config, "queue_retry_max"));
2396
2397    if (strcmp(type, "output") == 0) {
2398        int status;
2399        const xs_str *inbox  = xs_dict_get(q_item, "inbox");
2400        const xs_str *keyid  = xs_dict_get(q_item, "keyid");
2401        const xs_str *seckey = xs_dict_get(q_item, "seckey");
2402        const xs_dict *msg   = xs_dict_get(q_item, "message");
2403        int retries    = xs_number_get(xs_dict_get(q_item, "retries"));
2404        int p_status   = xs_number_get(xs_dict_get(q_item, "p_status"));
2405        xs *payload    = NULL;
2406        int p_size     = 0;
2407        int timeout    = 0;
2408
2409        if (xs_is_null(inbox) || xs_is_null(msg) || xs_is_null(keyid) || xs_is_null(seckey)) {
2410            srv_log(xs_fmt("output message error: missing fields"));
2411            return;
2412        }
2413
2414        if (is_instance_blocked(inbox)) {
2415            srv_debug(0, xs_fmt("discarded output message to blocked instance %s", inbox));
2416            return;
2417        }
2418
2419        /* deliver (if previous error status was a timeout, try now longer) */
2420        if (p_status == 599)
2421            timeout = xs_number_get(xs_dict_get_def(srv_config, "queue_timeout_2", "8"));
2422        else
2423            timeout = xs_number_get(xs_dict_get_def(srv_config, "queue_timeout", "6"));
2424
2425        if (timeout == 0)
2426            timeout = 6;
2427
2428        status = send_to_inbox_raw(keyid, seckey, inbox, msg, &payload, &p_size, timeout);
2429
2430        if (payload) {
2431            if (p_size > 64) {
2432                /* trim the message */
2433                payload[64] = '\0';
2434                payload = xs_str_cat(payload, "...");
2435            }
2436
2437            /* strip ugly control characters */
2438            payload = xs_replace_i(payload, "\n", "");
2439            payload = xs_replace_i(payload, "\r", "");
2440
2441            if (*payload)
2442                payload = xs_str_wrap_i(" [", payload, "]");
2443        }
2444        else
2445            payload = xs_str_new(NULL);
2446
2447        srv_log(xs_fmt("output message: sent to inbox %s %d%s", inbox, status, payload));
2448
2449        if (!valid_status(status)) {
2450            retries++;
2451
2452            /* if it's not the first time it fails with a timeout,
2453               penalize the server by skipping one retry */
2454            if (p_status == status && status == HTTP_STATUS_CLIENT_CLOSED_REQUEST)
2455                retries++;
2456
2457            /* error sending; requeue? */
2458            if (status == HTTP_STATUS_BAD_REQUEST
2459                || status == HTTP_STATUS_NOT_FOUND
2460                || status == HTTP_STATUS_METHOD_NOT_ALLOWED
2461                || status == HTTP_STATUS_GONE
2462                || status == HTTP_STATUS_UNPROCESSABLE_CONTENT
2463                || status < 0)
2464                /* explicit error: discard */
2465                srv_log(xs_fmt("output message: fatal error %s %d", inbox, status));
2466            else
2467            if (retries > queue_retry_max)
2468                srv_log(xs_fmt("output message: giving up %s %d", inbox, status));
2469            else {
2470                /* requeue */
2471                enqueue_output_raw(keyid, seckey, msg, inbox, retries, status);
2472                srv_log(xs_fmt("output message: requeue %s #%d", inbox, retries));
2473            }
2474        }
2475    }
2476    else
2477    if (strcmp(type, "email") == 0) {
2478        /* send this email */
2479        const xs_str *msg = xs_dict_get(q_item, "message");
2480        int retries = xs_number_get(xs_dict_get(q_item, "retries"));
2481
2482        if (!send_email(msg))
2483            srv_debug(1, xs_fmt("email message sent"));
2484        else {
2485            retries++;
2486
2487            if (retries > queue_retry_max)
2488                srv_log(xs_fmt("email giving up (errno: %d)", errno));
2489            else {
2490                /* requeue */
2491                srv_log(xs_fmt(
2492                    "email requeue #%d (errno: %d)", retries, errno));
2493
2494                enqueue_email(msg, retries);
2495            }
2496        }
2497    }
2498    else
2499    if (strcmp(type, "telegram") == 0) {
2500        /* send this via telegram */
2501        const char *bot   = xs_dict_get(q_item, "bot");
2502        const char *msg   = xs_dict_get(q_item, "message");
2503        xs *chat_id = xs_dup(xs_dict_get(q_item, "chat_id"));
2504        int status  = 0;
2505
2506        /* chat_id must start with a - */
2507        if (!xs_startswith(chat_id, "-"))
2508            chat_id = xs_str_wrap_i("-", chat_id, NULL);
2509
2510        xs *url  = xs_fmt("https:/" "/api.telegram.org/bot%s/sendMessage", bot);
2511        xs *body = xs_fmt("{\"chat_id\":%s,\"text\":\"%s\"}", chat_id, msg);
2512
2513        xs *headers = xs_dict_new();
2514        headers = xs_dict_append(headers, "content-type", "application/json");
2515
2516        xs *rsp = xs_http_request("POST", url, headers,
2517                                   body, strlen(body), &status, NULL, NULL, 0);
2518        rsp = xs_free(rsp);
2519
2520        srv_debug(0, xs_fmt("telegram post %d", status));
2521    }
2522    else
2523    if (strcmp(type, "ntfy") == 0) {
2524        /* send this via ntfy */
2525        const char *ntfy_server   = xs_dict_get(q_item, "ntfy_server");
2526        const char *msg   = xs_dict_get(q_item, "message");
2527        const char *ntfy_token   = xs_dict_get(q_item, "ntfy_token");
2528        int status  = 0;
2529
2530        xs *url  = xs_fmt("%s", ntfy_server);
2531        xs *body = xs_fmt("%s", msg);
2532
2533        xs *headers = xs_dict_new();
2534        headers = xs_dict_append(headers, "content-type", "text/plain");
2535        // Append the Authorization header only if ntfy_token is not NULL
2536         if (ntfy_token != NULL) {
2537             headers = xs_dict_append(headers, "Authorization", xs_fmt("Bearer %s", ntfy_token));
2538             }
2539
2540        xs *rsp = xs_http_request("POST", url, headers,
2541                                   body, strlen(body), &status, NULL, NULL, 0);
2542        rsp = xs_free(rsp);
2543
2544        srv_debug(0, xs_fmt("ntfy post %d", status));
2545    }
2546    else
2547    if (strcmp(type, "purge") == 0) {
2548        srv_log(xs_dup("purge start"));
2549
2550        purge_all();
2551
2552        srv_log(xs_dup("purge end"));
2553    }
2554    else
2555    if (strcmp(type, "input") == 0) {
2556        const xs_dict *msg = xs_dict_get(q_item, "message");
2557        const xs_dict *req = xs_dict_get(q_item, "req");
2558        int retries  = xs_number_get(xs_dict_get(q_item, "retries"));
2559
2560        /* do some instance-level checks */
2561        int r = process_input_message(NULL, msg, req);
2562
2563        if (r == 0) {
2564            /* transient error? retry */
2565            if (retries > queue_retry_max)
2566                srv_log(xs_fmt("shared input giving up"));
2567            else {
2568                /* reenqueue */
2569                enqueue_shared_input(msg, req, retries + 1);
2570                srv_log(xs_fmt("shared input requeue #%d", retries + 1));
2571            }
2572        }
2573        else
2574        if (r == 2) {
2575            /* redistribute the input message to all users */
2576            const char *ntid = xs_dict_get(q_item, "ntid");
2577            xs *tmpfn  = xs_fmt("%s/tmp/%s.json", srv_basedir, ntid);
2578            FILE *f;
2579
2580            if ((f = fopen(tmpfn, "w")) != NULL) {
2581                xs_json_dump(q_item, 4, f);
2582                fclose(f);
2583            }
2584
2585            xs *users = user_list();
2586            xs_list *p = users;
2587            const char *v;
2588            int cnt = 0;
2589
2590            while (xs_list_iter(&p, &v)) {
2591                snac user;
2592
2593                if (user_open(&user, v)) {
2594                    if (is_msg_for_me(&user, msg)) {
2595                        xs *fn = xs_fmt("%s/queue/%s.json", user.basedir, ntid);
2596
2597                        snac_debug(&user, 1,
2598                            xs_fmt("enqueue_input (from shared inbox) %s", xs_dict_get(msg, "id")));
2599
2600                        if (link(tmpfn, fn) < 0)
2601                            srv_log(xs_fmt("link(%s, %s) error", tmpfn, fn));
2602
2603                        cnt++;
2604                    }
2605
2606                    user_free(&user);
2607                }
2608            }
2609
2610            unlink(tmpfn);
2611
2612            if (cnt == 0) {
2613                srv_debug(1, xs_fmt("no valid recipients for %s", xs_dict_get(msg, "id")));
2614            }
2615        }
2616    }
2617    else
2618        srv_log(xs_fmt("unexpected q_item type '%s'", type));
2619}
2620
2621
2622int process_queue(void)
2623/* processes the global queue */
2624{
2625    int cnt = 0;
2626    xs *list = queue();
2627
2628    xs_list *p = list;
2629    const xs_str *fn;
2630
2631    while (xs_list_iter(&p, &fn)) {
2632        xs *q_item = dequeue(fn);
2633
2634        if (q_item != NULL) {
2635            job_post(q_item, 0);
2636            cnt++;
2637        }
2638    }
2639
2640    return cnt;
2641}
2642
2643
2644/** HTTP handlers */
2645
2646int activitypub_get_handler(const xs_dict *req, const char *q_path,
2647                            char **body, int *b_size, char **ctype)
2648{
2649    int status = HTTP_STATUS_OK;
2650    const char *accept = xs_dict_get(req, "accept");
2651    snac snac;
2652    xs *msg = NULL;
2653
2654    if (accept == NULL)
2655        return 0;
2656
2657    if (xs_str_in(accept, "application/activity+json") == -1 &&
2658        xs_str_in(accept, "application/ld+json") == -1)
2659        return 0;
2660
2661    xs *l = xs_split_n(q_path, "/", 2);
2662    const char *uid;
2663    const char *p_path;
2664
2665    uid = xs_list_get(l, 1);
2666    if (!user_open(&snac, uid)) {
2667        /* invalid user */
2668        srv_debug(1, xs_fmt("activitypub_get_handler bad user %s", uid));
2669        return HTTP_STATUS_NOT_FOUND;
2670    }
2671
2672    p_path = xs_list_get(l, 2);
2673
2674    *ctype  = "application/activity+json";
2675
2676    if (p_path == NULL) {
2677        /* if there was no component after the user, it's an actor request */
2678        msg = msg_actor(&snac);
2679        *ctype = "application/ld+json; profile=\"https://www.w3.org/ns/activitystreams\"";
2680
2681        const char *ua = xs_dict_get(req, "user-agent");
2682
2683        snac_debug(&snac, 0, xs_fmt("serving actor [%s]", ua ? ua : "No UA"));
2684    }
2685    else
2686    if (strcmp(p_path, "outbox") == 0 || strcmp(p_path, "featured") == 0) {
2687        xs *id = xs_fmt("%s/%s", snac.actor, p_path);
2688        xs *list = xs_list_new();
2689        msg = msg_collection(&snac, id);
2690        const char *v;
2691        int tc = 0;
2692
2693        /* get the public outbox or the pinned list */
2694        xs *elems = *p_path == 'o' ? timeline_simple_list(&snac, "public", 0, 20) : pinned_list(&snac);
2695
2696        while (xs_list_next(elems, &v, &tc)) {
2697            xs *i = NULL;
2698
2699            if (valid_status(object_get_by_md5(v, &i))) {
2700                const char *type = xs_dict_get(i, "type");
2701                const char *id   = xs_dict_get(i, "id");
2702
2703                if (type && id && strcmp(type, "Note") == 0 && xs_startswith(id, snac.actor)) {
2704                    xs *c_msg = msg_create(&snac, i);
2705                    list = xs_list_append(list, c_msg);
2706                }
2707            }
2708        }
2709
2710        /* replace the 'orderedItems' with the latest posts */
2711        xs *items = xs_number_new(xs_list_len(list));
2712        msg = xs_dict_set(msg, "orderedItems", list);
2713        msg = xs_dict_set(msg, "totalItems",   items);
2714    }
2715    else
2716    if (strcmp(p_path, "followers") == 0 || strcmp(p_path, "following") == 0) {
2717        xs *id = xs_fmt("%s/%s", snac.actor, p_path);
2718        msg = msg_collection(&snac, id);
2719    }
2720    else
2721    if (xs_startswith(p_path, "p/")) {
2722        xs *id = xs_fmt("%s/%s", snac.actor, p_path);
2723
2724        status = object_get(id, &msg);
2725
2726        /* don't return non-public objects */
2727        if (valid_status(status) && !is_msg_public(msg))
2728            status = HTTP_STATUS_NOT_FOUND;
2729    }
2730    else
2731        status = HTTP_STATUS_NOT_FOUND;
2732
2733    if (status == HTTP_STATUS_OK && msg != NULL) {
2734        *body   = xs_json_dumps(msg, 4);
2735        *b_size = strlen(*body);
2736    }
2737
2738    snac_debug(&snac, 1, xs_fmt("activitypub_get_handler serving %s %d", q_path, status));
2739
2740    user_free(&snac);
2741
2742    return status;
2743}
2744
2745
2746int activitypub_post_handler(const xs_dict *req, const char *q_path,
2747                             char *payload, int p_size,
2748                             char **body, int *b_size, char **ctype)
2749/* processes an input message */
2750{
2751    (void)b_size;
2752
2753    int status = HTTP_STATUS_ACCEPTED;
2754    const char *i_ctype = xs_dict_get(req, "content-type");
2755    snac snac;
2756    const char *v;
2757
2758    if (i_ctype == NULL) {
2759        *body  = xs_str_new("no content-type");
2760        *ctype = "text/plain";
2761        return HTTP_STATUS_BAD_REQUEST;
2762    }
2763
2764    if (xs_is_null(payload)) {
2765        *body  = xs_str_new("no payload");
2766        *ctype = "text/plain";
2767        return HTTP_STATUS_BAD_REQUEST;
2768    }
2769
2770    if (xs_str_in(i_ctype, "application/activity+json") == -1 &&
2771        xs_str_in(i_ctype, "application/ld+json") == -1)
2772        return 0;
2773
2774    /* decode the message */
2775    xs *msg = xs_json_loads(payload);
2776    const char *id = xs_dict_get(msg, "id");
2777
2778    if (msg == NULL) {
2779        srv_log(xs_fmt("activitypub_post_handler JSON error %s", q_path));
2780
2781        srv_archive_error("activitypub_post_handler", "JSON error", req, payload);
2782
2783        *body  = xs_str_new("JSON error");
2784        *ctype = "text/plain";
2785        return HTTP_STATUS_BAD_REQUEST;
2786    }
2787
2788    if (id && is_instance_blocked(id)) {
2789        srv_debug(1, xs_fmt("full instance block for %s", id));
2790
2791        *body  = xs_str_new("blocked");
2792        *ctype = "text/plain";
2793        return HTTP_STATUS_FORBIDDEN;
2794    }
2795
2796    /* get the user and path */
2797    xs *l = xs_split_n(q_path, "/", 2);
2798
2799    if (xs_list_len(l) == 2 && strcmp(xs_list_get(l, 1), "shared-inbox") == 0) {
2800        enqueue_shared_input(msg, req, 0);
2801        return HTTP_STATUS_ACCEPTED;
2802    }
2803
2804    if (xs_list_len(l) != 3 || strcmp(xs_list_get(l, 2), "inbox") != 0) {
2805        /* strange q_path */
2806        srv_debug(1, xs_fmt("activitypub_post_handler unsupported path %s", q_path));
2807        return HTTP_STATUS_NOT_FOUND;
2808    }
2809
2810    const char *uid = xs_list_get(l, 1);
2811    if (!user_open(&snac, uid)) {
2812        /* invalid user */
2813        srv_debug(1, xs_fmt("activitypub_post_handler bad user %s", uid));
2814        return HTTP_STATUS_NOT_FOUND;
2815    }
2816
2817    /* if it has a digest, check it now, because
2818       later the payload won't be exactly the same */
2819    if ((v = xs_dict_get(req, "digest")) != NULL) {
2820        xs *s1 = xs_sha256_base64(payload, p_size);
2821        xs *s2 = xs_fmt("SHA-256=%s", s1);
2822
2823        if (strcmp(s2, v) != 0) {
2824            srv_log(xs_fmt("digest check FAILED"));
2825
2826            *body  = xs_str_new("bad digest");
2827            *ctype = "text/plain";
2828            status = HTTP_STATUS_BAD_REQUEST;
2829        }
2830    }
2831
2832    /* if the message is from a muted actor, reject it right now */
2833    if (!xs_is_null(v = xs_dict_get(msg, "actor")) && *v) {
2834        if (is_muted(&snac, v)) {
2835            snac_log(&snac, xs_fmt("rejected message from MUTEd actor %s", v));
2836
2837            *body  = xs_str_new("rejected");
2838            *ctype = "text/plain";
2839            status = HTTP_STATUS_FORBIDDEN;
2840        }
2841    }
2842
2843    if (valid_status(status)) {
2844        enqueue_input(&snac, msg, req, 0);
2845        *ctype = "application/activity+json";
2846    }
2847
2848    user_free(&snac);
2849
2850    return status;
2851}