all repos — honk @ 5036d46acc40279489fba5156682addfed218121

my fork of honk

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	for _, h := range honks {
 39		h.What += "ed"
 40		if h.What == "tonked" {
 41			h.What = "honked back"
 42			h.Style = "subtle"
 43		}
 44		if !h.Public {
 45			h.Style += " limited"
 46		}
 47		translate(h)
 48		if h.Whofore == 2 || h.Whofore == 3 {
 49			h.URL = h.XID
 50			if h.What != "bonked" {
 51				h.Noise = re_memes.ReplaceAllString(h.Noise, "")
 52				h.Noise = mentionize(h.Noise)
 53				h.Noise = ontologize(h.Noise)
 54			}
 55			h.Username, h.Handle = handles(h.Honker)
 56		} else {
 57			_, h.Handle = handles(h.Honker)
 58			h.Username = h.Handle
 59			if len(h.Username) > 20 {
 60				h.Username = h.Username[:20] + ".."
 61			}
 62			if h.URL == "" {
 63				h.URL = h.XID
 64			}
 65		}
 66		if h.Oonker != "" {
 67			_, h.Oondle = handles(h.Oonker)
 68		}
 69		zap := make(map[*Donk]bool)
 70		h.Precis = unpucker(h.Precis)
 71		h.Noise = unpucker(h.Noise)
 72		h.Open = "open"
 73		if userid == -1 {
 74			if h.Precis != "" {
 75				h.Open = ""
 76			}
 77		} else {
 78			if badword := unsee(userid, h); badword != "" {
 79				if h.Precis == "" {
 80					h.Precis = badword
 81				}
 82				h.Open = ""
 83			} else if h.Precis == "unspecified horror" {
 84				h.Precis = ""
 85			}
 86		}
 87		if len(h.Noise) > 4000 && h.Open == "open" {
 88			if h.Precis == "" {
 89				h.Precis = "really freaking long"
 90			}
 91			h.Open = ""
 92		}
 93
 94		h.HTPrecis, _ = filt.String(h.Precis)
 95		h.HTML, _ = filt.String(h.Noise)
 96		emuxifier := func(e string) string {
 97			for _, d := range h.Donks {
 98				if d.Name == e {
 99					zap[d] = true
100					if d.Local {
101						return fmt.Sprintf(`<img class="emu" title="%s" src="/d/%s">`, d.Name, d.XID)
102					}
103				}
104			}
105			return e
106		}
107		h.HTPrecis = template.HTML(re_emus.ReplaceAllStringFunc(string(h.HTPrecis), emuxifier))
108		h.HTML = template.HTML(re_emus.ReplaceAllStringFunc(string(h.HTML), emuxifier))
109		j := 0
110		for i := 0; i < len(h.Donks); i++ {
111			if !zap[h.Donks[i]] {
112				h.Donks[j] = h.Donks[i]
113				j++
114			}
115		}
116		h.Donks = h.Donks[:j]
117	}
118}
119
120func replaceimg(node *html.Node) string {
121	src := htfilter.GetAttr(node, "src")
122	alt := htfilter.GetAttr(node, "alt")
123	//title := GetAttr(node, "title")
124	if htfilter.HasClass(node, "Emoji") && alt != "" {
125		return alt
126	}
127	alt = html.EscapeString(alt)
128	src = html.EscapeString(src)
129	d := finddonk(src)
130	if d != nil {
131		src = fmt.Sprintf("https://%s/d/%s", serverName, d.XID)
132		return fmt.Sprintf(`<img alt="%s" title="%s" src="%s">`, alt, alt, src)
133	}
134	return fmt.Sprintf(`&lt;img alt="%s" src="<a href="%s">%s<a>"&gt;`, alt, src, src)
135}
136
137func inlineimgs(node *html.Node) string {
138	src := htfilter.GetAttr(node, "src")
139	alt := htfilter.GetAttr(node, "alt")
140	//title := GetAttr(node, "title")
141	if htfilter.HasClass(node, "Emoji") && alt != "" {
142		return alt
143	}
144	alt = html.EscapeString(alt)
145	src = html.EscapeString(src)
146	if !strings.HasPrefix(src, "https://"+serverName+"/") {
147		d := savedonk(src, "image", alt, "image", true)
148		if d != nil {
149			src = fmt.Sprintf("https://%s/d/%s", serverName, d.XID)
150		}
151	}
152	log.Printf("inline img with src: %s", src)
153	return fmt.Sprintf(`<img alt="%s" title="%s" src="%s>`, alt, alt, src)
154}
155
156func translate(honk *Honk) {
157	if honk.Format == "html" {
158		return
159	}
160	noise := honk.Noise
161	if strings.HasPrefix(noise, "DZ:") {
162		idx := strings.Index(noise, "\n")
163		if idx == -1 {
164			honk.Precis = noise
165			noise = ""
166		} else {
167			honk.Precis = noise[:idx]
168			noise = noise[idx+1:]
169		}
170	}
171	honk.Precis = strings.TrimSpace(honk.Precis)
172
173	noise = strings.TrimSpace(noise)
174	noise = quickrename(noise, honk.UserID)
175	noise = obfusbreak(noise)
176
177	honk.Noise = noise
178	honk.Onts = oneofakind(ontologies(honk.Noise))
179}
180
181func shortxid(xid string) string {
182	idx := strings.LastIndexByte(xid, '/')
183	if idx == -1 {
184		return xid
185	}
186	return xid[idx+1:]
187}
188
189func xfiltrate() string {
190	letters := "BCDFGHJKLMNPQRSTVWXYZbcdfghjklmnpqrstvwxyz1234567891234567891234"
191	var b [18]byte
192	rand.Read(b[:])
193	for i, c := range b {
194		b[i] = letters[c&63]
195	}
196	s := string(b[:])
197	return s
198}
199
200var re_hashes = regexp.MustCompile(`(?:^| )#[[:alnum:]][[:alnum:]_-]*`)
201
202func ontologies(s string) []string {
203	m := re_hashes.FindAllString(s, -1)
204	j := 0
205	for _, h := range m {
206		if h[0] == '&' {
207			continue
208		}
209		if h[0] != '#' {
210			h = h[1:]
211		}
212		m[j] = h
213		j++
214	}
215	return m[:j]
216}
217
218type Mention struct {
219	who   string
220	where string
221}
222
223var re_mentions = regexp.MustCompile(`@[[:alnum:]._-]+@[[:alnum:].-]*[[:alnum:]]`)
224var re_urltions = regexp.MustCompile(`@https://\S+`)
225
226func grapevine(s string) []string {
227	var mentions []string
228	m := re_mentions.FindAllString(s, -1)
229	for i := range m {
230		where := gofish(m[i])
231		if where != "" {
232			mentions = append(mentions, where)
233		}
234	}
235	m = re_urltions.FindAllString(s, -1)
236	for i := range m {
237		mentions = append(mentions, m[i][1:])
238	}
239	return mentions
240}
241
242func bunchofgrapes(s string) []Mention {
243	m := re_mentions.FindAllString(s, -1)
244	var mentions []Mention
245	for i := range m {
246		where := gofish(m[i])
247		if where != "" {
248			mentions = append(mentions, Mention{who: m[i], where: where})
249		}
250	}
251	m = re_urltions.FindAllString(s, -1)
252	for i := range m {
253		mentions = append(mentions, Mention{who: m[i][1:], where: m[i][1:]})
254	}
255	return mentions
256}
257
258type Emu struct {
259	ID   string
260	Name string
261}
262
263var re_link = regexp.MustCompile(`@?https?://[^\s"]+[\w/)]`)
264var re_emus = regexp.MustCompile(`:[[:alnum:]_-]+:`)
265
266func herdofemus(noise string) []Emu {
267	m := re_emus.FindAllString(noise, -1)
268	m = oneofakind(m)
269	var emus []Emu
270	for _, e := range m {
271		fname := e[1 : len(e)-1]
272		_, err := os.Stat("emus/" + fname + ".png")
273		if err != nil {
274			continue
275		}
276		url := fmt.Sprintf("https://%s/emu/%s.png", serverName, fname)
277		emus = append(emus, Emu{ID: url, Name: e})
278	}
279	return emus
280}
281
282var re_memes = regexp.MustCompile("meme: ?([[:alnum:]_.-]+)")
283
284func memetize(honk *Honk) {
285	repl := func(x string) string {
286		name := x[5:]
287		if name[0] == ' ' {
288			name = name[1:]
289		}
290		fd, err := os.Open("memes/" + name)
291		if err != nil {
292			log.Printf("no meme for %s", name)
293			return x
294		}
295		var peek [512]byte
296		n, _ := fd.Read(peek[:])
297		ct := http.DetectContentType(peek[:n])
298		fd.Close()
299
300		url := fmt.Sprintf("https://%s/meme/%s", serverName, name)
301		fileid, err := savefile("", name, name, url, ct, false, nil)
302		if err != nil {
303			log.Printf("error saving meme: %s", err)
304			return x
305		}
306		var d Donk
307		d.FileID = fileid
308		d.XID = ""
309		d.Name = name
310		d.Media = ct
311		d.URL = url
312		d.Local = false
313		honk.Donks = append(honk.Donks, &d)
314		return ""
315	}
316	honk.Noise = re_memes.ReplaceAllStringFunc(honk.Noise, repl)
317}
318
319var re_bolder = regexp.MustCompile(`(^|\W)\*\*([\w\s,.!?':_-]+)\*\*($|\W)`)
320var re_italicer = regexp.MustCompile(`(^|\W)\*([\w\s,.!?':_-]+)\*($|\W)`)
321var re_bigcoder = regexp.MustCompile("```\n?((?s:.*?))\n?```\n?")
322var re_coder = regexp.MustCompile("`([^`]*)`")
323var re_quoter = regexp.MustCompile(`(?m:^&gt; (.*)\n?)`)
324
325func markitzero(s string) string {
326	var bigcodes []string
327	bigsaver := func(code string) string {
328		bigcodes = append(bigcodes, code)
329		return "``````"
330	}
331	s = re_bigcoder.ReplaceAllStringFunc(s, bigsaver)
332	var lilcodes []string
333	lilsaver := func(code string) string {
334		lilcodes = append(lilcodes, code)
335		return "`x`"
336	}
337	s = re_coder.ReplaceAllStringFunc(s, lilsaver)
338	s = re_bolder.ReplaceAllString(s, "$1<b>$2</b>$3")
339	s = re_italicer.ReplaceAllString(s, "$1<i>$2</i>$3")
340	s = re_quoter.ReplaceAllString(s, "<blockquote>$1</blockquote><p>")
341	lilun := func(s string) string {
342		code := lilcodes[0]
343		lilcodes = lilcodes[1:]
344		return code
345	}
346	s = re_coder.ReplaceAllStringFunc(s, lilun)
347	bigun := func(s string) string {
348		code := bigcodes[0]
349		bigcodes = bigcodes[1:]
350		return code
351	}
352	s = re_bigcoder.ReplaceAllStringFunc(s, bigun)
353	s = re_bigcoder.ReplaceAllString(s, "<pre><code>$1</code></pre><p>")
354	s = re_coder.ReplaceAllString(s, "<code>$1</code>")
355	return s
356}
357
358func obfusbreak(s string) string {
359	s = strings.TrimSpace(s)
360	s = strings.Replace(s, "\r", "", -1)
361	s = html.EscapeString(s)
362	// dammit go
363	s = strings.Replace(s, "&#39;", "'", -1)
364	linkfn := func(url string) string {
365		if url[0] == '@' {
366			return url
367		}
368		addparen := false
369		adddot := false
370		if strings.HasSuffix(url, ")") && strings.IndexByte(url, '(') == -1 {
371			url = url[:len(url)-1]
372			addparen = true
373		}
374		if strings.HasSuffix(url, ".") {
375			url = url[:len(url)-1]
376			adddot = true
377		}
378		url = fmt.Sprintf(`<a class="mention u-url" href="%s">%s</a>`, url, url)
379		if adddot {
380			url += "."
381		}
382		if addparen {
383			url += ")"
384		}
385		return url
386	}
387	s = re_link.ReplaceAllStringFunc(s, linkfn)
388
389	s = markitzero(s)
390
391	s = strings.Replace(s, "\n", "<br>", -1)
392	return s
393}
394
395var re_quickmention = regexp.MustCompile("(^| )@[[:alnum:]]+ ")
396
397func quickrename(s string, userid int64) string {
398	return re_quickmention.ReplaceAllStringFunc(s, func(m string) string {
399		prefix := ""
400		if m[0] == ' ' {
401			prefix = " "
402			m = m[1:]
403		}
404		prefix += "@"
405		m = m[1:]
406		m = m[:len(m)-1]
407
408		row := stmtOneHonker.QueryRow(m, userid)
409		var xid string
410		err := row.Scan(&xid)
411		if err == nil {
412			_, name := handles(xid)
413			if name != "" {
414				m = name
415			}
416		}
417		return prefix + m + " "
418	})
419}
420
421func mentionize(s string) string {
422	s = re_mentions.ReplaceAllStringFunc(s, func(m string) string {
423		where := gofish(m)
424		if where == "" {
425			return m
426		}
427		who := m[0 : 1+strings.IndexByte(m[1:], '@')]
428		return fmt.Sprintf(`<span class="h-card"><a class="u-url mention" href="%s">%s</a></span>`,
429			html.EscapeString(where), html.EscapeString(who))
430	})
431	s = re_urltions.ReplaceAllStringFunc(s, func(m string) string {
432		return fmt.Sprintf(`<span class="h-card"><a class="u-url mention" href="%s">%s</a></span>`,
433			html.EscapeString(m[1:]), html.EscapeString(m))
434	})
435	return s
436}
437
438func ontologize(s string) string {
439	s = re_hashes.ReplaceAllStringFunc(s, func(o string) string {
440		if o[0] == '&' {
441			return o
442		}
443		p := ""
444		h := o
445		if h[0] != '#' {
446			p = h[:1]
447			h = h[1:]
448		}
449		return fmt.Sprintf(`%s<a class="mention u-url" href="https://%s/o/%s">%s</a>`, p, serverName,
450			strings.ToLower(h[1:]), h)
451	})
452	return s
453}
454
455var re_unurl = regexp.MustCompile("https://([^/]+).*/([^/]+)")
456var re_urlhost = regexp.MustCompile("https://([^/ ]+)")
457
458func originate(u string) string {
459	m := re_urlhost.FindStringSubmatch(u)
460	if len(m) > 1 {
461		return m[1]
462	}
463	return ""
464}
465
466var allhandles = make(map[string]string)
467var handlelock sync.Mutex
468
469// handle, handle@host
470func handles(xid string) (string, string) {
471	if xid == "" {
472		return "", ""
473	}
474	handlelock.Lock()
475	handle := allhandles[xid]
476	handlelock.Unlock()
477	if handle == "" {
478		handle = findhandle(xid)
479		handlelock.Lock()
480		allhandles[xid] = handle
481		handlelock.Unlock()
482	}
483	if handle == xid {
484		return xid, xid
485	}
486	return handle, handle + "@" + originate(xid)
487}
488
489func findhandle(xid string) string {
490	row := stmtGetXonker.QueryRow(xid, "handle")
491	var handle string
492	err := row.Scan(&handle)
493	if err != nil {
494		p, _ := investigate(xid)
495		if p == nil {
496			m := re_unurl.FindStringSubmatch(xid)
497			if len(m) > 2 {
498				handle = m[2]
499			} else {
500				handle = xid
501			}
502		} else {
503			handle = p.Handle
504		}
505		_, err = stmtSaveXonker.Exec(xid, handle, "handle")
506		if err != nil {
507			log.Printf("error saving handle: %s", err)
508		}
509	}
510	return handle
511}
512
513var handleprelock sync.Mutex
514
515func prehandle(xid string) {
516	handleprelock.Lock()
517	defer handleprelock.Unlock()
518	handles(xid)
519}
520
521func prepend(s string, x []string) []string {
522	return append([]string{s}, x...)
523}
524
525// pleroma leaks followers addressed posts to followers
526func butnottooloud(aud []string) {
527	for i, a := range aud {
528		if strings.HasSuffix(a, "/followers") {
529			aud[i] = ""
530		}
531	}
532}
533
534func keepitquiet(aud []string) bool {
535	for _, a := range aud {
536		if a == thewholeworld {
537			return false
538		}
539	}
540	return true
541}
542
543func firstclass(honk *Honk) bool {
544	return honk.Audience[0] == thewholeworld
545}
546
547func oneofakind(a []string) []string {
548	var x []string
549	for n, s := range a {
550		if s != "" {
551			x = append(x, s)
552			for i := n + 1; i < len(a); i++ {
553				if a[i] == s {
554					a[i] = ""
555				}
556			}
557		}
558	}
559	return x
560}
561
562var ziggies = make(map[string]*rsa.PrivateKey)
563var zaggies = make(map[string]*rsa.PublicKey)
564var ziggylock sync.Mutex
565
566func ziggy(username string) (keyname string, key *rsa.PrivateKey) {
567	ziggylock.Lock()
568	key = ziggies[username]
569	ziggylock.Unlock()
570	if key == nil {
571		db := opendatabase()
572		row := db.QueryRow("select seckey from users where username = ?", username)
573		var data string
574		row.Scan(&data)
575		var err error
576		key, _, err = httpsig.DecodeKey(data)
577		if err != nil {
578			log.Printf("error decoding %s seckey: %s", username, err)
579			return
580		}
581		ziggylock.Lock()
582		ziggies[username] = key
583		ziggylock.Unlock()
584	}
585	keyname = fmt.Sprintf("https://%s/%s/%s#key", serverName, userSep, username)
586	return
587}
588
589func zaggy(keyname string) (key *rsa.PublicKey) {
590	ziggylock.Lock()
591	key = zaggies[keyname]
592	ziggylock.Unlock()
593	if key != nil {
594		return
595	}
596	row := stmtGetXonker.QueryRow(keyname, "pubkey")
597	var data string
598	err := row.Scan(&data)
599	if err != nil {
600		log.Printf("hitting the webs for missing pubkey: %s", keyname)
601		j, err := GetJunk(keyname)
602		if err != nil {
603			log.Printf("error getting %s pubkey: %s", keyname, err)
604			return
605		}
606		keyobj, ok := j.GetMap("publicKey")
607		if ok {
608			j = keyobj
609		}
610		data, ok = j.GetString("publicKeyPem")
611		if !ok {
612			log.Printf("error finding %s pubkey", keyname)
613			return
614		}
615		_, ok = j.GetString("owner")
616		if !ok {
617			log.Printf("error finding %s pubkey owner", keyname)
618			return
619		}
620		_, key, err = httpsig.DecodeKey(data)
621		if err != nil {
622			log.Printf("error decoding %s pubkey: %s", keyname, err)
623			return
624		}
625		_, err = stmtSaveXonker.Exec(keyname, data, "pubkey")
626		if err != nil {
627			log.Printf("error saving key: %s", err)
628		}
629	} else {
630		_, key, err = httpsig.DecodeKey(data)
631		if err != nil {
632			log.Printf("error decoding %s pubkey: %s", keyname, err)
633			return
634		}
635	}
636	ziggylock.Lock()
637	zaggies[keyname] = key
638	ziggylock.Unlock()
639	return
640}
641
642func makeitworksomehowwithoutregardforkeycontinuity(keyname string, r *http.Request, payload []byte) (string, error) {
643	_, err := stmtDeleteXonker.Exec(keyname, "pubkey")
644	if err != nil {
645		log.Printf("error deleting key: %s", err)
646	}
647	ziggylock.Lock()
648	delete(zaggies, keyname)
649	ziggylock.Unlock()
650	return httpsig.VerifyRequest(r, payload, zaggy)
651}
652
653func keymatch(keyname string, actor string) string {
654	hash := strings.IndexByte(keyname, '#')
655	if hash == -1 {
656		hash = len(keyname)
657	}
658	owner := keyname[0:hash]
659	if owner == actor {
660		return originate(actor)
661	}
662	return ""
663}