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 "crypto/sha512"
22 "fmt"
23 "html/template"
24 "io"
25 "log"
26 "net/http"
27 "os"
28 "regexp"
29 "strings"
30 "sync"
31
32 "golang.org/x/net/html"
33 "humungus.tedunangst.com/r/webs/cache"
34 "humungus.tedunangst.com/r/webs/htfilter"
35 "humungus.tedunangst.com/r/webs/httpsig"
36 "humungus.tedunangst.com/r/webs/templates"
37)
38
39var allowedclasses = make(map[string]bool)
40
41func init() {
42 allowedclasses["kw"] = true
43 allowedclasses["bi"] = true
44 allowedclasses["st"] = true
45 allowedclasses["nm"] = true
46 allowedclasses["tp"] = true
47 allowedclasses["op"] = true
48 allowedclasses["cm"] = true
49 allowedclasses["al"] = true
50 allowedclasses["dl"] = true
51}
52
53func reverbolate(userid int64, honks []*Honk) {
54 for _, h := range honks {
55 h.What += "ed"
56 if h.What == "tonked" {
57 h.What = "honked back"
58 h.Style += " subtle"
59 }
60 if !h.Public {
61 h.Style += " limited"
62 }
63 translate(h, false)
64 if h.Whofore == 2 || h.Whofore == 3 {
65 h.URL = h.XID
66 if h.What != "bonked" {
67 h.Noise = re_memes.ReplaceAllString(h.Noise, "")
68 h.Noise = mentionize(h.Noise)
69 h.Noise = ontologize(h.Noise)
70 }
71 h.Username, h.Handle = handles(h.Honker)
72 } else {
73 _, h.Handle = handles(h.Honker)
74 short := shortname(userid, h.Honker)
75 if short != "" {
76 h.Username = short
77 } else {
78 h.Username = h.Handle
79 if len(h.Username) > 20 {
80 h.Username = h.Username[:20] + ".."
81 }
82 }
83 if h.URL == "" {
84 h.URL = h.XID
85 }
86 }
87 if h.Oonker != "" {
88 _, h.Oondle = handles(h.Oonker)
89 }
90 h.Precis = demoji(h.Precis)
91 h.Noise = demoji(h.Noise)
92 h.Open = "open"
93
94 zap := make(map[string]bool)
95 {
96 var htf htfilter.Filter
97 htf.Imager = replaceimgsand(zap, false)
98 htf.SpanClasses = allowedclasses
99 p, _ := htf.String(h.Precis)
100 n, _ := htf.String(h.Noise)
101 h.Precis = string(p)
102 h.Noise = string(n)
103 }
104
105 if userid == -1 {
106 if h.Precis != "" {
107 h.Open = ""
108 }
109 } else {
110 unsee(userid, h)
111 if h.Open == "open" && h.Precis == "unspecified horror" {
112 h.Precis = ""
113 }
114 }
115 if len(h.Noise) > 6000 && h.Open == "open" {
116 if h.Precis == "" {
117 h.Precis = "really freaking long"
118 }
119 h.Open = ""
120 }
121
122 emuxifier := func(e string) string {
123 for _, d := range h.Donks {
124 if d.Name == e {
125 zap[d.XID] = true
126 if d.Local {
127 return fmt.Sprintf(`<img class="emu" title="%s" src="/d/%s">`, d.Name, d.XID)
128 }
129 }
130 }
131 return e
132 }
133 h.Precis = re_emus.ReplaceAllStringFunc(h.Precis, emuxifier)
134 h.Noise = re_emus.ReplaceAllStringFunc(h.Noise, emuxifier)
135
136 j := 0
137 for i := 0; i < len(h.Donks); i++ {
138 if !zap[h.Donks[i].XID] {
139 h.Donks[j] = h.Donks[i]
140 j++
141 }
142 }
143 h.Donks = h.Donks[:j]
144
145 h.HTPrecis = template.HTML(h.Precis)
146 h.HTML = template.HTML(h.Noise)
147 }
148}
149
150func replaceimgsand(zap map[string]bool, absolute bool) func(node *html.Node) string {
151 return func(node *html.Node) string {
152 src := htfilter.GetAttr(node, "src")
153 alt := htfilter.GetAttr(node, "alt")
154 //title := GetAttr(node, "title")
155 if htfilter.HasClass(node, "Emoji") && alt != "" {
156 return alt
157 }
158 d := finddonk(src)
159 if d != nil {
160 zap[d.XID] = true
161 base := ""
162 if absolute {
163 base = "https://" + serverName
164 }
165 return string(templates.Sprintf(`<img alt="%s" title="%s" src="%s/d/%s">`, alt, alt, base, d.XID))
166 }
167 return string(templates.Sprintf(`<img alt="%s" src="<a href="%s">%s<a>">`, alt, src, src))
168 }
169}
170
171func inlineimgsfor(honk *Honk) func(node *html.Node) string {
172 return func(node *html.Node) string {
173 src := htfilter.GetAttr(node, "src")
174 alt := htfilter.GetAttr(node, "alt")
175 d := savedonk(src, "image", alt, "image", true)
176 if d != nil {
177 honk.Donks = append(honk.Donks, d)
178 }
179 log.Printf("inline img with src: %s", src)
180 return ""
181 }
182}
183
184func imaginate(honk *Honk) {
185 var htf htfilter.Filter
186 htf.Imager = inlineimgsfor(honk)
187 htf.String(honk.Noise)
188}
189
190func translate(honk *Honk, redoimages bool) {
191 if honk.Format == "html" {
192 return
193 }
194 noise := honk.Noise
195 if strings.HasPrefix(noise, "DZ:") {
196 idx := strings.Index(noise, "\n")
197 if idx == -1 {
198 honk.Precis = noise
199 noise = ""
200 } else {
201 honk.Precis = noise[:idx]
202 noise = noise[idx+1:]
203 }
204 }
205 honk.Precis = strings.TrimSpace(honk.Precis)
206
207 noise = strings.TrimSpace(noise)
208 noise = quickrename(noise, honk.UserID)
209 noise = markitzero(noise)
210 honk.Noise = noise
211 honk.Onts = oneofakind(ontologies(honk.Noise))
212
213 if redoimages {
214 zap := make(map[string]bool)
215 {
216 var htf htfilter.Filter
217 htf.Imager = replaceimgsand(zap, true)
218 htf.SpanClasses = allowedclasses
219 p, _ := htf.String(honk.Precis)
220 n, _ := htf.String(honk.Noise)
221 honk.Precis = string(p)
222 honk.Noise = string(n)
223 }
224 j := 0
225 for i := 0; i < len(honk.Donks); i++ {
226 if !zap[honk.Donks[i].XID] {
227 honk.Donks[j] = honk.Donks[i]
228 j++
229 }
230 }
231 honk.Donks = honk.Donks[:j]
232
233 honk.Noise = re_memes.ReplaceAllString(honk.Noise, "")
234 honk.Noise = ontologize(mentionize(honk.Noise))
235 honk.Noise = strings.Replace(honk.Noise, "<a href=", "<a class=\"mention u-url\" href=", -1)
236 }
237}
238
239func xcelerate(b []byte) string {
240 letters := "BCDFGHJKLMNPQRSTVWXYZbcdfghjklmnpqrstvwxyz1234567891234567891234"
241 for i, c := range b {
242 b[i] = letters[c&63]
243 }
244 s := string(b)
245 return s
246}
247
248func shortxid(xid string) string {
249 h := sha512.New512_256()
250 io.WriteString(h, xid)
251 return xcelerate(h.Sum(nil)[:20])
252}
253
254func xfiltrate() string {
255 var b [18]byte
256 rand.Read(b[:])
257 return xcelerate(b[:])
258}
259
260var re_hashes = regexp.MustCompile(`(?:^| )#[[:alnum:]][[:alnum:]_-]*`)
261
262func ontologies(s string) []string {
263 m := re_hashes.FindAllString(s, -1)
264 j := 0
265 for _, h := range m {
266 if h[0] == '&' {
267 continue
268 }
269 if h[0] != '#' {
270 h = h[1:]
271 }
272 m[j] = h
273 j++
274 }
275 return m[:j]
276}
277
278type Mention struct {
279 who string
280 where string
281}
282
283var re_mentions = regexp.MustCompile(`@[[:alnum:]._-]+@[[:alnum:].-]*[[:alnum:]]`)
284var re_urltions = regexp.MustCompile(`@https://\S+`)
285
286func grapevine(s string) []string {
287 var mentions []string
288 m := re_mentions.FindAllString(s, -1)
289 for i := range m {
290 where := gofish(m[i])
291 if where != "" {
292 mentions = append(mentions, where)
293 }
294 }
295 m = re_urltions.FindAllString(s, -1)
296 for i := range m {
297 mentions = append(mentions, m[i][1:])
298 }
299 return mentions
300}
301
302func bunchofgrapes(s string) []Mention {
303 m := re_mentions.FindAllString(s, -1)
304 var mentions []Mention
305 for i := range m {
306 where := gofish(m[i])
307 if where != "" {
308 mentions = append(mentions, Mention{who: m[i], where: where})
309 }
310 }
311 m = re_urltions.FindAllString(s, -1)
312 for i := range m {
313 mentions = append(mentions, Mention{who: m[i][1:], where: m[i][1:]})
314 }
315 return mentions
316}
317
318type Emu struct {
319 ID string
320 Name string
321}
322
323var re_emus = regexp.MustCompile(`:[[:alnum:]_-]+:`)
324
325func herdofemus(noise string) []Emu {
326 m := re_emus.FindAllString(noise, -1)
327 m = oneofakind(m)
328 var emus []Emu
329 for _, e := range m {
330 fname := e[1 : len(e)-1]
331 _, err := os.Stat("emus/" + fname + ".png")
332 if err != nil {
333 continue
334 }
335 url := fmt.Sprintf("https://%s/emu/%s.png", serverName, fname)
336 emus = append(emus, Emu{ID: url, Name: e})
337 }
338 return emus
339}
340
341var re_memes = regexp.MustCompile("meme: ?([[:alnum:]_.-]+)")
342
343func memetize(honk *Honk) {
344 repl := func(x string) string {
345 name := x[5:]
346 if name[0] == ' ' {
347 name = name[1:]
348 }
349 fd, err := os.Open("memes/" + name)
350 if err != nil {
351 log.Printf("no meme for %s", name)
352 return x
353 }
354 var peek [512]byte
355 n, _ := fd.Read(peek[:])
356 ct := http.DetectContentType(peek[:n])
357 fd.Close()
358
359 url := fmt.Sprintf("https://%s/meme/%s", serverName, name)
360 fileid, err := savefile("", name, name, url, ct, false, nil)
361 if err != nil {
362 log.Printf("error saving meme: %s", err)
363 return x
364 }
365 d := &Donk{
366 FileID: fileid,
367 XID: "",
368 Name: name,
369 Media: ct,
370 URL: url,
371 Local: false,
372 }
373 honk.Donks = append(honk.Donks, d)
374 return ""
375 }
376 honk.Noise = re_memes.ReplaceAllStringFunc(honk.Noise, repl)
377}
378
379var re_quickmention = regexp.MustCompile("(^| )@[[:alnum:]]+( |$)")
380
381func quickrename(s string, userid int64) string {
382 nonstop := true
383 for nonstop {
384 nonstop = false
385 s = re_quickmention.ReplaceAllStringFunc(s, func(m string) string {
386 prefix := ""
387 if m[0] == ' ' {
388 prefix = " "
389 m = m[1:]
390 }
391 prefix += "@"
392 m = m[1:]
393 if m[len(m)-1] == ' ' {
394 m = m[:len(m)-1]
395 }
396
397 xid := fullname(m, userid)
398
399 if xid != "" {
400 _, name := handles(xid)
401 if name != "" {
402 nonstop = true
403 m = name
404 }
405 }
406 return prefix + m + " "
407 })
408 }
409 return s
410}
411
412var shortnames = cache.New(cache.Options{Filler: func(userid int64) (map[string]string, bool) {
413 honkers := gethonkers(userid)
414 m := make(map[string]string)
415 for _, h := range honkers {
416 m[h.XID] = h.Name
417 }
418 return m, true
419}, Invalidator: &honkerinvalidator})
420
421func shortname(userid int64, xid string) string {
422 var m map[string]string
423 ok := shortnames.Get(userid, &m)
424 if ok {
425 return m[xid]
426 }
427 return ""
428}
429
430var fullnames = cache.New(cache.Options{Filler: func(userid int64) (map[string]string, bool) {
431 honkers := gethonkers(userid)
432 m := make(map[string]string)
433 for _, h := range honkers {
434 m[h.Name] = h.XID
435 }
436 return m, true
437}, Invalidator: &honkerinvalidator})
438
439func fullname(name string, userid int64) string {
440 var m map[string]string
441 ok := fullnames.Get(userid, &m)
442 if ok {
443 return m[name]
444 }
445 return ""
446}
447
448func mentionize(s string) string {
449 s = re_mentions.ReplaceAllStringFunc(s, func(m string) string {
450 where := gofish(m)
451 if where == "" {
452 return m
453 }
454 who := m[0 : 1+strings.IndexByte(m[1:], '@')]
455 return fmt.Sprintf(`<span class="h-card"><a class="u-url mention" href="%s">%s</a></span>`,
456 html.EscapeString(where), html.EscapeString(who))
457 })
458 s = re_urltions.ReplaceAllStringFunc(s, func(m string) string {
459 return fmt.Sprintf(`<span class="h-card"><a class="u-url mention" href="%s">%s</a></span>`,
460 html.EscapeString(m[1:]), html.EscapeString(m))
461 })
462 return s
463}
464
465func ontologize(s string) string {
466 s = re_hashes.ReplaceAllStringFunc(s, func(o string) string {
467 if o[0] == '&' {
468 return o
469 }
470 p := ""
471 h := o
472 if h[0] != '#' {
473 p = h[:1]
474 h = h[1:]
475 }
476 return fmt.Sprintf(`%s<a href="https://%s/o/%s">%s</a>`, p, serverName,
477 strings.ToLower(h[1:]), h)
478 })
479 return s
480}
481
482var re_unurl = regexp.MustCompile("https://([^/]+).*/([^/]+)")
483var re_urlhost = regexp.MustCompile("https://([^/ ]+)")
484
485func originate(u string) string {
486 m := re_urlhost.FindStringSubmatch(u)
487 if len(m) > 1 {
488 return m[1]
489 }
490 return ""
491}
492
493var allhandles = cache.New(cache.Options{Filler: func(xid string) (string, bool) {
494 row := stmtGetXonker.QueryRow(xid, "handle")
495 var handle string
496 err := row.Scan(&handle)
497 if err != nil {
498 info, err := investigate(xid)
499 if err != nil {
500 m := re_unurl.FindStringSubmatch(xid)
501 if len(m) > 2 {
502 handle = m[2]
503 } else {
504 handle = xid
505 }
506 } else {
507 handle = info.Name
508 _, err = stmtSaveXonker.Exec(xid, handle, "handle")
509 if err != nil {
510 log.Printf("error saving handle: %s", err)
511 }
512 }
513 }
514 return handle, true
515}})
516
517// handle, handle@host
518func handles(xid string) (string, string) {
519 if xid == "" {
520 return "", ""
521 }
522 var handle string
523 allhandles.Get(xid, &handle)
524 if handle == xid {
525 return xid, xid
526 }
527 return handle, handle + "@" + originate(xid)
528}
529
530func prepend(s string, x []string) []string {
531 return append([]string{s}, x...)
532}
533
534// pleroma leaks followers addressed posts to followers
535func butnottooloud(aud []string) {
536 for i, a := range aud {
537 if strings.HasSuffix(a, "/followers") {
538 aud[i] = ""
539 }
540 }
541}
542
543func keepitquiet(aud []string) bool {
544 for _, a := range aud {
545 if a == thewholeworld {
546 return false
547 }
548 }
549 return true
550}
551
552func firstclass(honk *Honk) bool {
553 return honk.Audience[0] == thewholeworld
554}
555
556func oneofakind(a []string) []string {
557 seen := make(map[string]bool)
558 seen[""] = true
559 j := 0
560 for _, s := range a {
561 if !seen[s] {
562 seen[s] = true
563 a[j] = s
564 j++
565 }
566 }
567 return a[:j]
568}
569
570var ziggies = cache.New(cache.Options{Filler: func(userid int64) (*KeyInfo, bool) {
571 var user *WhatAbout
572 ok := somenumberedusers.Get(userid, &user)
573 if !ok {
574 return nil, false
575 }
576 ki := new(KeyInfo)
577 ki.keyname = user.URL + "#key"
578 ki.seckey = user.SecKey
579 return ki, true
580}})
581
582func ziggy(userid int64) *KeyInfo {
583 var ki *KeyInfo
584 ziggies.Get(userid, &ki)
585 return ki
586}
587
588var zaggies = make(map[string]*rsa.PublicKey)
589var zaggylock sync.Mutex
590
591func zaggy(keyname string) (key *rsa.PublicKey) {
592 zaggylock.Lock()
593 key = zaggies[keyname]
594 zaggylock.Unlock()
595 if key != nil {
596 return
597 }
598 row := stmtGetXonker.QueryRow(keyname, "pubkey")
599 var data string
600 err := row.Scan(&data)
601 if err != nil {
602 log.Printf("hitting the webs for missing pubkey: %s", keyname)
603 j, err := GetJunk(keyname)
604 if err != nil {
605 log.Printf("error getting %s pubkey: %s", keyname, err)
606 return
607 }
608 keyobj, ok := j.GetMap("publicKey")
609 if ok {
610 j = keyobj
611 }
612 data, ok = j.GetString("publicKeyPem")
613 if !ok {
614 log.Printf("error finding %s pubkey", keyname)
615 return
616 }
617 _, ok = j.GetString("owner")
618 if !ok {
619 log.Printf("error finding %s pubkey owner", keyname)
620 return
621 }
622 _, key, err = httpsig.DecodeKey(data)
623 if err != nil {
624 log.Printf("error decoding %s pubkey: %s", keyname, err)
625 return
626 }
627 _, err = stmtSaveXonker.Exec(keyname, data, "pubkey")
628 if err != nil {
629 log.Printf("error saving key: %s", err)
630 }
631 } else {
632 _, key, err = httpsig.DecodeKey(data)
633 if err != nil {
634 log.Printf("error decoding %s pubkey: %s", keyname, err)
635 return
636 }
637 }
638 zaggylock.Lock()
639 zaggies[keyname] = key
640 zaggylock.Unlock()
641 return
642}
643
644func makeitworksomehowwithoutregardforkeycontinuity(keyname string, r *http.Request, payload []byte) (string, error) {
645 _, err := stmtDeleteXonker.Exec(keyname, "pubkey")
646 if err != nil {
647 log.Printf("error deleting key: %s", err)
648 }
649 zaggylock.Lock()
650 delete(zaggies, keyname)
651 zaggylock.Unlock()
652 return httpsig.VerifyRequest(r, payload, zaggy)
653}
654
655func keymatch(keyname string, actor string) string {
656 hash := strings.IndexByte(keyname, '#')
657 if hash == -1 {
658 hash = len(keyname)
659 }
660 owner := keyname[0:hash]
661 if owner == actor {
662 return originate(actor)
663 }
664 return ""
665}