shell bypass 403
'use strict'
var chunkedPush = require('../util/chunked-push.js')
var chunkedSplice = require('../util/chunked-splice.js')
var classifyCharacter = require('../util/classify-character.js')
var movePoint = require('../util/move-point.js')
var resolveAll = require('../util/resolve-all.js')
var shallow = require('../util/shallow.js')
var attention = {
name: 'attention',
tokenize: tokenizeAttention,
resolveAll: resolveAllAttention
}
function resolveAllAttention(events, context) {
var index = -1
var open
var group
var text
var openingSequence
var closingSequence
var use
var nextEvents
var offset // Walk through all events.
//
// Note: performance of this is fine on an mb of normal markdown, but it’s
// a bottleneck for malicious stuff.
while (++index < events.length) {
// Find a token that can close.
if (
events[index][0] === 'enter' &&
events[index][1].type === 'attentionSequence' &&
events[index][1]._close
) {
open = index // Now walk back to find an opener.
while (open--) {
// Find a token that can open the closer.
if (
events[open][0] === 'exit' &&
events[open][1].type === 'attentionSequence' &&
events[open][1]._open && // If the markers are the same:
context.sliceSerialize(events[open][1]).charCodeAt(0) ===
context.sliceSerialize(events[index][1]).charCodeAt(0)
) {
// If the opening can close or the closing can open,
// and the close size *is not* a multiple of three,
// but the sum of the opening and closing size *is* multiple of three,
// then don’t match.
if (
(events[open][1]._close || events[index][1]._open) &&
(events[index][1].end.offset - events[index][1].start.offset) % 3 &&
!(
(events[open][1].end.offset -
events[open][1].start.offset +
events[index][1].end.offset -
events[index][1].start.offset) %
3
)
) {
continue
} // Number of markers to use from the sequence.
use =
events[open][1].end.offset - events[open][1].start.offset > 1 &&
events[index][1].end.offset - events[index][1].start.offset > 1
? 2
: 1
openingSequence = {
type: use > 1 ? 'strongSequence' : 'emphasisSequence',
start: movePoint(shallow(events[open][1].end), -use),
end: shallow(events[open][1].end)
}
closingSequence = {
type: use > 1 ? 'strongSequence' : 'emphasisSequence',
start: shallow(events[index][1].start),
end: movePoint(shallow(events[index][1].start), use)
}
text = {
type: use > 1 ? 'strongText' : 'emphasisText',
start: shallow(events[open][1].end),
end: shallow(events[index][1].start)
}
group = {
type: use > 1 ? 'strong' : 'emphasis',
start: shallow(openingSequence.start),
end: shallow(closingSequence.end)
}
events[open][1].end = shallow(openingSequence.start)
events[index][1].start = shallow(closingSequence.end)
nextEvents = [] // If there are more markers in the opening, add them before.
if (events[open][1].end.offset - events[open][1].start.offset) {
nextEvents = chunkedPush(nextEvents, [
['enter', events[open][1], context],
['exit', events[open][1], context]
])
} // Opening.
nextEvents = chunkedPush(nextEvents, [
['enter', group, context],
['enter', openingSequence, context],
['exit', openingSequence, context],
['enter', text, context]
]) // Between.
nextEvents = chunkedPush(
nextEvents,
resolveAll(
context.parser.constructs.insideSpan.null,
events.slice(open + 1, index),
context
)
) // Closing.
nextEvents = chunkedPush(nextEvents, [
['exit', text, context],
['enter', closingSequence, context],
['exit', closingSequence, context],
['exit', group, context]
]) // If there are more markers in the closing, add them after.
if (events[index][1].end.offset - events[index][1].start.offset) {
offset = 2
nextEvents = chunkedPush(nextEvents, [
['enter', events[index][1], context],
['exit', events[index][1], context]
])
} else {
offset = 0
}
chunkedSplice(events, open - 1, index - open + 3, nextEvents)
index = open + nextEvents.length - offset - 2
break
}
}
}
} // Remove remaining sequences.
index = -1
while (++index < events.length) {
if (events[index][1].type === 'attentionSequence') {
events[index][1].type = 'data'
}
}
return events
}
function tokenizeAttention(effects, ok) {
var before = classifyCharacter(this.previous)
var marker
return start
function start(code) {
effects.enter('attentionSequence')
marker = code
return sequence(code)
}
function sequence(code) {
var token
var after
var open
var close
if (code === marker) {
effects.consume(code)
return sequence
}
token = effects.exit('attentionSequence')
after = classifyCharacter(code)
open = !after || (after === 2 && before)
close = !before || (before === 2 && after)
token._open = marker === 42 ? open : open && (before || !close)
token._close = marker === 42 ? close : close && (after || !open)
return ok(code)
}
}
module.exports = attention