fun.go (view raw)
1//
2// Copyright (c) 2019 Ted Unangst <tedu@tedunangst.com>
3//
4// Permission to use, copy, modify, and distribute this software for any
5// purpose with or without fee is hereby granted, provided that the above
6// copyright notice and this permission notice appear in all copies.
7//
8// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11// ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13// ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14// OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15
16package main
17
18import (
19 "crypto/rand"
20 "crypto/rsa"
21 "fmt"
22 "html/template"
23 "log"
24 "net/http"
25 "os"
26 "regexp"
27 "strings"
28 "sync"
29
30 "golang.org/x/net/html"
31 "humungus.tedunangst.com/r/webs/htfilter"
32 "humungus.tedunangst.com/r/webs/httpsig"
33)
34
35func reverbolate(userid int64, honks []*Honk) {
36 filt := htfilter.New()
37 filt.Imager = replaceimg
38 zilences := getzilences(userid)
39 for _, h := range honks {
40 h.What += "ed"
41 if h.What == "tonked" {
42 h.What = "honked back"
43 h.Style = "subtle"
44 }
45 if !h.Public {
46 h.Style += " limited"
47 }
48 translate(h)
49 if h.Whofore == 2 || h.Whofore == 3 {
50 h.URL = h.XID
51 if h.What != "bonked" {
52 h.Noise = re_memes.ReplaceAllString(h.Noise, "")
53 h.Noise = mentionize(h.Noise)
54 h.Noise = ontologize(h.Noise)
55 }
56 h.Username, h.Handle = handles(h.Honker)
57 } else {
58 _, h.Handle = handles(h.Honker)
59 h.Username = h.Handle
60 if len(h.Username) > 20 {
61 h.Username = h.Username[:20] + ".."
62 }
63 if h.URL == "" {
64 h.URL = h.XID
65 }
66 }
67 if h.Oonker != "" {
68 _, h.Oondle = handles(h.Oonker)
69 }
70 zap := make(map[*Donk]bool)
71 h.Precis = unpucker(h.Precis)
72 h.Noise = unpucker(h.Noise)
73 h.Open = "open"
74 if badword := unsee(zilences, h.Precis, h.Noise, h.Donks); badword != "" {
75 if h.Precis == "" {
76 h.Precis = badword
77 }
78 h.Open = ""
79 } else if h.Precis == "unspecified horror" {
80 h.Precis = ""
81 }
82 h.HTPrecis, _ = filt.String(h.Precis)
83 h.HTML, _ = filt.String(h.Noise)
84 emuxifier := func(e string) string {
85 for _, d := range h.Donks {
86 if d.Name == e {
87 zap[d] = true
88 if d.Local {
89 return fmt.Sprintf(`<img class="emu" title="%s" src="/d/%s">`, d.Name, d.XID)
90 }
91 }
92 }
93 return e
94 }
95 h.HTPrecis = template.HTML(re_emus.ReplaceAllStringFunc(string(h.HTPrecis), emuxifier))
96 h.HTML = template.HTML(re_emus.ReplaceAllStringFunc(string(h.HTML), emuxifier))
97 j := 0
98 for i := 0; i < len(h.Donks); i++ {
99 if !zap[h.Donks[i]] {
100 h.Donks[j] = h.Donks[i]
101 j++
102 }
103 }
104 h.Donks = h.Donks[:j]
105 }
106}
107
108func replaceimg(node *html.Node) string {
109 src := htfilter.GetAttr(node, "src")
110 alt := htfilter.GetAttr(node, "alt")
111 //title := GetAttr(node, "title")
112 if htfilter.HasClass(node, "Emoji") && alt != "" {
113 return alt
114 }
115 alt = html.EscapeString(alt)
116 src = html.EscapeString(src)
117 return fmt.Sprintf(`<img alt="%s" src="<a href="%s">%s<a>">`, alt, src, src)
118}
119
120func translate(honk *Honk) {
121 if honk.Format == "html" {
122 return
123 }
124 noise := honk.Noise
125 if strings.HasPrefix(noise, "DZ:") {
126 idx := strings.Index(noise, "\n")
127 if idx == -1 {
128 honk.Precis = noise
129 noise = ""
130 } else {
131 honk.Precis = noise[:idx]
132 noise = noise[idx+1:]
133 }
134 }
135 honk.Precis = strings.TrimSpace(honk.Precis)
136
137 noise = strings.TrimSpace(noise)
138 noise = quickrename(noise, honk.UserID)
139 noise = obfusbreak(noise)
140
141 honk.Noise = noise
142 honk.Onts = oneofakind(ontologies(honk.Noise))
143}
144
145func unsee(zilences []*regexp.Regexp, precis string, noise string, donks []*Donk) string {
146 for _, z := range zilences {
147 if z.MatchString(precis) || z.MatchString(noise) {
148 if precis == "" {
149 w := z.String()
150 return w[6 : len(w)-3]
151 }
152 return precis
153 }
154 for _, d := range donks {
155 if z.MatchString(d.Desc) {
156 if precis == "" {
157 w := z.String()
158 return w[6 : len(w)-3]
159 }
160 return precis
161 }
162 }
163 }
164 return ""
165}
166
167func osmosis(honks []*Honk, userid int64) []*Honk {
168 zords := getzords(userid)
169 j := 0
170outer:
171 for _, h := range honks {
172 for _, z := range zords {
173 if z.MatchString(h.Precis) || z.MatchString(h.Noise) {
174 continue outer
175 }
176 for _, d := range h.Donks {
177 if z.MatchString(d.Desc) {
178 continue outer
179 }
180 }
181 }
182 honks[j] = h
183 j++
184 }
185 honks = honks[0:j]
186 return honks
187}
188
189func shortxid(xid string) string {
190 idx := strings.LastIndexByte(xid, '/')
191 if idx == -1 {
192 return xid
193 }
194 return xid[idx+1:]
195}
196
197func xfiltrate() string {
198 letters := "BCDFGHJKLMNPQRSTVWXYZbcdfghjklmnpqrstvwxyz1234567891234567891234"
199 var b [18]byte
200 rand.Read(b[:])
201 for i, c := range b {
202 b[i] = letters[c&63]
203 }
204 s := string(b[:])
205 return s
206}
207
208var re_hashes = regexp.MustCompile(`(?:^| )#[[:alnum:]][[:alnum:]_-]*`)
209
210func ontologies(s string) []string {
211 m := re_hashes.FindAllString(s, -1)
212 j := 0
213 for _, h := range m {
214 if h[0] == '&' {
215 continue
216 }
217 if h[0] != '#' {
218 h = h[1:]
219 }
220 m[j] = h
221 j++
222 }
223 return m[:j]
224}
225
226type Mention struct {
227 who string
228 where string
229}
230
231var re_mentions = regexp.MustCompile(`@[[:alnum:]._-]+@[[:alnum:].-]*[[:alnum:]]`)
232var re_urltions = regexp.MustCompile(`@https://\S+`)
233
234func grapevine(s string) []string {
235 var mentions []string
236 m := re_mentions.FindAllString(s, -1)
237 for i := range m {
238 where := gofish(m[i])
239 if where != "" {
240 mentions = append(mentions, where)
241 }
242 }
243 m = re_urltions.FindAllString(s, -1)
244 for i := range m {
245 mentions = append(mentions, m[i][1:])
246 }
247 return mentions
248}
249
250func bunchofgrapes(s string) []Mention {
251 m := re_mentions.FindAllString(s, -1)
252 var mentions []Mention
253 for i := range m {
254 where := gofish(m[i])
255 if where != "" {
256 mentions = append(mentions, Mention{who: m[i], where: where})
257 }
258 }
259 m = re_urltions.FindAllString(s, -1)
260 for i := range m {
261 mentions = append(mentions, Mention{who: m[i][1:], where: m[i][1:]})
262 }
263 return mentions
264}
265
266type Emu struct {
267 ID string
268 Name string
269}
270
271var re_link = regexp.MustCompile(`@?https?://[^\s"]+[\w/)]`)
272var re_emus = regexp.MustCompile(`:[[:alnum:]_-]+:`)
273
274func herdofemus(noise string) []Emu {
275 m := re_emus.FindAllString(noise, -1)
276 m = oneofakind(m)
277 var emus []Emu
278 for _, e := range m {
279 fname := e[1 : len(e)-1]
280 _, err := os.Stat("emus/" + fname + ".png")
281 if err != nil {
282 continue
283 }
284 url := fmt.Sprintf("https://%s/emu/%s.png", serverName, fname)
285 emus = append(emus, Emu{ID: url, Name: e})
286 }
287 return emus
288}
289
290var re_memes = regexp.MustCompile("meme: ?([[:alnum:]_.-]+)")
291
292func memetize(honk *Honk) {
293 repl := func(x string) string {
294 name := x[5:]
295 if name[0] == ' ' {
296 name = name[1:]
297 }
298 fd, err := os.Open("memes/" + name)
299 if err != nil {
300 log.Printf("no meme for %s", name)
301 return x
302 }
303 var peek [512]byte
304 n, _ := fd.Read(peek[:])
305 ct := http.DetectContentType(peek[:n])
306 fd.Close()
307
308 url := fmt.Sprintf("https://%s/meme/%s", serverName, name)
309 res, err := stmtSaveFile.Exec("", name, name, url, ct, 0, "")
310 if err != nil {
311 log.Printf("error saving meme: %s", err)
312 return x
313 }
314 var d Donk
315 d.FileID, _ = res.LastInsertId()
316 d.XID = ""
317 d.Name = name
318 d.Media = ct
319 d.URL = url
320 d.Local = false
321 honk.Donks = append(honk.Donks, &d)
322 return ""
323 }
324 honk.Noise = re_memes.ReplaceAllStringFunc(honk.Noise, repl)
325}
326
327var re_bolder = regexp.MustCompile(`(^|\W)\*\*([\w\s,.!?'-]+)\*\*($|\W)`)
328var re_italicer = regexp.MustCompile(`(^|\W)\*([\w\s,.!?'-]+)\*($|\W)`)
329var re_bigcoder = regexp.MustCompile("```\n?((?s:.*?))\n?```\n?")
330var re_coder = regexp.MustCompile("`([^`]*)`")
331var re_quoter = regexp.MustCompile(`(?m:^> (.*)\n?)`)
332
333func markitzero(s string) string {
334 var bigcodes []string
335 bigsaver := func(code string) string {
336 bigcodes = append(bigcodes, code)
337 return "``````"
338 }
339 s = re_bigcoder.ReplaceAllStringFunc(s, bigsaver)
340 var lilcodes []string
341 lilsaver := func(code string) string {
342 lilcodes = append(lilcodes, code)
343 return "`x`"
344 }
345 s = re_coder.ReplaceAllStringFunc(s, lilsaver)
346 s = re_bolder.ReplaceAllString(s, "$1<b>$2</b>$3")
347 s = re_italicer.ReplaceAllString(s, "$1<i>$2</i>$3")
348 s = re_quoter.ReplaceAllString(s, "<blockquote>$1</blockquote><p>")
349 lilun := func(s string) string {
350 code := lilcodes[0]
351 lilcodes = lilcodes[1:]
352 return code
353 }
354 s = re_coder.ReplaceAllStringFunc(s, lilun)
355 bigun := func(s string) string {
356 code := bigcodes[0]
357 bigcodes = bigcodes[1:]
358 return code
359 }
360 s = re_bigcoder.ReplaceAllStringFunc(s, bigun)
361 s = re_bigcoder.ReplaceAllString(s, "<pre><code>$1</code></pre><p>")
362 s = re_coder.ReplaceAllString(s, "<code>$1</code>")
363 return s
364}
365
366func obfusbreak(s string) string {
367 s = strings.TrimSpace(s)
368 s = strings.Replace(s, "\r", "", -1)
369 s = html.EscapeString(s)
370 // dammit go
371 s = strings.Replace(s, "'", "'", -1)
372 linkfn := func(url string) string {
373 if url[0] == '@' {
374 return url
375 }
376 addparen := false
377 adddot := false
378 if strings.HasSuffix(url, ")") && strings.IndexByte(url, '(') == -1 {
379 url = url[:len(url)-1]
380 addparen = true
381 }
382 if strings.HasSuffix(url, ".") {
383 url = url[:len(url)-1]
384 adddot = true
385 }
386 url = fmt.Sprintf(`<a class="mention u-url" href="%s">%s</a>`, url, url)
387 if adddot {
388 url += "."
389 }
390 if addparen {
391 url += ")"
392 }
393 return url
394 }
395 s = re_link.ReplaceAllStringFunc(s, linkfn)
396
397 s = markitzero(s)
398
399 s = strings.Replace(s, "\n", "<br>", -1)
400 return s
401}
402
403var re_quickmention = regexp.MustCompile("(^| )@[[:alnum:]]+ ")
404
405func quickrename(s string, userid int64) string {
406 return re_quickmention.ReplaceAllStringFunc(s, func(m string) string {
407 prefix := ""
408 if m[0] == ' ' {
409 prefix = " "
410 m = m[1:]
411 }
412 prefix += "@"
413 m = m[1:]
414 m = m[:len(m)-1]
415
416 row := stmtOneHonker.QueryRow(m, userid)
417 var xid string
418 err := row.Scan(&xid)
419 if err == nil {
420 _, name := handles(xid)
421 if name != "" {
422 m = name
423 }
424 }
425 return prefix + m + " "
426 })
427}
428
429func mentionize(s string) string {
430 s = re_mentions.ReplaceAllStringFunc(s, func(m string) string {
431 where := gofish(m)
432 if where == "" {
433 return m
434 }
435 who := m[0 : 1+strings.IndexByte(m[1:], '@')]
436 return fmt.Sprintf(`<span class="h-card"><a class="u-url mention" href="%s">%s</a></span>`,
437 html.EscapeString(where), html.EscapeString(who))
438 })
439 s = re_urltions.ReplaceAllStringFunc(s, func(m string) string {
440 return fmt.Sprintf(`<span class="h-card"><a class="u-url mention" href="%s">%s</a></span>`,
441 html.EscapeString(m[1:]), html.EscapeString(m))
442 })
443 return s
444}
445
446func ontologize(s string) string {
447 s = re_hashes.ReplaceAllStringFunc(s, func(o string) string {
448 if o[0] == '&' {
449 return o
450 }
451 p := ""
452 h := o
453 if h[0] != '#' {
454 p = h[:1]
455 h = h[1:]
456 }
457 return fmt.Sprintf(`%s<a class="mention u-url" href="https://%s/o/%s">%s</a>`, p, serverName,
458 strings.ToLower(h[1:]), h)
459 })
460 return s
461}
462
463var re_unurl = regexp.MustCompile("https://([^/]+).*/([^/]+)")
464var re_urlhost = regexp.MustCompile("https://([^/ ]+)")
465
466func originate(u string) string {
467 m := re_urlhost.FindStringSubmatch(u)
468 if len(m) > 1 {
469 return m[1]
470 }
471 return ""
472}
473
474var allhandles = make(map[string]string)
475var handlelock sync.Mutex
476
477// handle, handle@host
478func handles(xid string) (string, string) {
479 if xid == "" {
480 return "", ""
481 }
482 handlelock.Lock()
483 handle := allhandles[xid]
484 handlelock.Unlock()
485 if handle == "" {
486 handle = findhandle(xid)
487 handlelock.Lock()
488 allhandles[xid] = handle
489 handlelock.Unlock()
490 }
491 if handle == xid {
492 return xid, xid
493 }
494 return handle, handle + "@" + originate(xid)
495}
496
497func findhandle(xid string) string {
498 row := stmtGetXonker.QueryRow(xid, "handle")
499 var handle string
500 err := row.Scan(&handle)
501 if err != nil {
502 p, _ := investigate(xid)
503 if p == nil {
504 m := re_unurl.FindStringSubmatch(xid)
505 if len(m) > 2 {
506 handle = m[2]
507 } else {
508 handle = xid
509 }
510 } else {
511 handle = p.Handle
512 }
513 _, err = stmtSaveXonker.Exec(xid, handle, "handle")
514 if err != nil {
515 log.Printf("error saving handle: %s", err)
516 }
517 }
518 return handle
519}
520
521var handleprelock sync.Mutex
522
523func prehandle(xid string) {
524 handleprelock.Lock()
525 defer handleprelock.Unlock()
526 handles(xid)
527}
528
529func prepend(s string, x []string) []string {
530 return append([]string{s}, x...)
531}
532
533// pleroma leaks followers addressed posts to followers
534func butnottooloud(aud []string) {
535 for i, a := range aud {
536 if strings.HasSuffix(a, "/followers") {
537 aud[i] = ""
538 }
539 }
540}
541
542func keepitquiet(aud []string) bool {
543 for _, a := range aud {
544 if a == thewholeworld {
545 return false
546 }
547 }
548 return true
549}
550
551func firstclass(honk *Honk) bool {
552 return honk.Audience[0] == thewholeworld
553}
554
555func oneofakind(a []string) []string {
556 var x []string
557 for n, s := range a {
558 if s != "" {
559 x = append(x, s)
560 for i := n + 1; i < len(a); i++ {
561 if a[i] == s {
562 a[i] = ""
563 }
564 }
565 }
566 }
567 return x
568}
569
570var ziggies = make(map[string]*rsa.PrivateKey)
571var zaggies = make(map[string]*rsa.PublicKey)
572var ziggylock sync.Mutex
573
574func ziggy(username string) (keyname string, key *rsa.PrivateKey) {
575 ziggylock.Lock()
576 key = ziggies[username]
577 ziggylock.Unlock()
578 if key == nil {
579 db := opendatabase()
580 row := db.QueryRow("select seckey from users where username = ?", username)
581 var data string
582 row.Scan(&data)
583 var err error
584 key, _, err = httpsig.DecodeKey(data)
585 if err != nil {
586 log.Printf("error decoding %s seckey: %s", username, err)
587 return
588 }
589 ziggylock.Lock()
590 ziggies[username] = key
591 ziggylock.Unlock()
592 }
593 keyname = fmt.Sprintf("https://%s/%s/%s#key", serverName, userSep, username)
594 return
595}
596
597func zaggy(keyname string) (key *rsa.PublicKey) {
598 ziggylock.Lock()
599 key = zaggies[keyname]
600 ziggylock.Unlock()
601 if key != nil {
602 return
603 }
604 row := stmtGetXonker.QueryRow(keyname, "pubkey")
605 var data string
606 err := row.Scan(&data)
607 if err != nil {
608 log.Printf("hitting the webs for missing pubkey: %s", keyname)
609 j, err := GetJunk(keyname)
610 if err != nil {
611 log.Printf("error getting %s pubkey: %s", keyname, err)
612 return
613 }
614 keyobj, ok := j.GetMap("publicKey")
615 if ok {
616 j = keyobj
617 }
618 data, ok = j.GetString("publicKeyPem")
619 if !ok {
620 log.Printf("error finding %s pubkey", keyname)
621 return
622 }
623 _, ok = j.GetString("owner")
624 if !ok {
625 log.Printf("error finding %s pubkey owner", keyname)
626 return
627 }
628 _, key, err = httpsig.DecodeKey(data)
629 if err != nil {
630 log.Printf("error decoding %s pubkey: %s", keyname, err)
631 return
632 }
633 _, err = stmtSaveXonker.Exec(keyname, data, "pubkey")
634 if err != nil {
635 log.Printf("error saving key: %s", err)
636 }
637 } else {
638 _, key, err = httpsig.DecodeKey(data)
639 if err != nil {
640 log.Printf("error decoding %s pubkey: %s", keyname, err)
641 return
642 }
643 }
644 ziggylock.Lock()
645 zaggies[keyname] = key
646 ziggylock.Unlock()
647 return
648}
649
650func makeitworksomehowwithoutregardforkeycontinuity(keyname string, r *http.Request, payload []byte) (string, error) {
651 _, err := stmtDeleteXonker.Exec(keyname, "pubkey")
652 if err != nil {
653 log.Printf("error deleting key: %s", err)
654 }
655 ziggylock.Lock()
656 delete(zaggies, keyname)
657 ziggylock.Unlock()
658 return httpsig.VerifyRequest(r, payload, zaggy)
659}
660
661var thumbbiters map[int64]map[string]bool
662var zordses map[int64][]*regexp.Regexp
663var zilences map[int64][]*regexp.Regexp
664var thumblock sync.Mutex
665
666func bitethethumbs() {
667 rows, err := stmtThumbBiters.Query()
668 if err != nil {
669 log.Printf("error getting thumbbiters: %s", err)
670 return
671 }
672 defer rows.Close()
673
674 thumblock.Lock()
675 defer thumblock.Unlock()
676 thumbbiters = make(map[int64]map[string]bool)
677 zordses = make(map[int64][]*regexp.Regexp)
678 zilences = make(map[int64][]*regexp.Regexp)
679 for rows.Next() {
680 var userid int64
681 var name, wherefore string
682 err = rows.Scan(&userid, &name, &wherefore)
683 if err != nil {
684 log.Printf("error scanning zonker: %s", err)
685 continue
686 }
687 if wherefore == "zord" || wherefore == "zilence" {
688 zord := "\\b(?i:" + name + ")\\b"
689 re, err := regexp.Compile(zord)
690 if err != nil {
691 log.Printf("error compiling zord: %s", err)
692 } else {
693 if wherefore == "zord" {
694 zordses[userid] = append(zordses[userid], re)
695 } else {
696 zilences[userid] = append(zilences[userid], re)
697 }
698 }
699 continue
700 }
701 m := thumbbiters[userid]
702 if m == nil {
703 m = make(map[string]bool)
704 thumbbiters[userid] = m
705 }
706 m[name] = true
707 }
708}
709
710func getzords(userid int64) []*regexp.Regexp {
711 thumblock.Lock()
712 defer thumblock.Unlock()
713 return zordses[userid]
714}
715
716func getzilences(userid int64) []*regexp.Regexp {
717 thumblock.Lock()
718 defer thumblock.Unlock()
719 return zilences[userid]
720}
721
722func thoudostbitethythumb(userid int64, who []string, objid string) bool {
723 thumblock.Lock()
724 biters := thumbbiters[userid]
725 thumblock.Unlock()
726 objwhere := originate(objid)
727 if objwhere != "" && biters[objwhere] {
728 log.Printf("thumbbiter: %s", objid)
729 return true
730 }
731 for _, w := range who {
732 if biters[w] {
733 log.Printf("thumbbiter: %s", w)
734 return true
735 }
736 where := originate(w)
737 if where != "" {
738 if biters[where] {
739 log.Printf("thumbbiter: %s", w)
740 return true
741 }
742 }
743 }
744 return false
745}
746
747func stealthmode(userid int64, r *http.Request) bool {
748 agent := r.UserAgent()
749 agent = originate(agent)
750 addr := r.Header.Get("X-Forwarded-For")
751 thumblock.Lock()
752 biters := thumbbiters[userid]
753 thumblock.Unlock()
754 fake := (agent != "" && biters[agent]) || (addr != "" && biters[addr])
755 if fake {
756 log.Printf("faking 404 for %s from %s", agent, addr)
757 }
758 return fake
759}
760
761func keymatch(keyname string, actor string) string {
762 hash := strings.IndexByte(keyname, '#')
763 if hash == -1 {
764 hash = len(keyname)
765 }
766 owner := keyname[0:hash]
767 if owner == actor {
768 return originate(actor)
769 }
770 return ""
771}