MarseyWorld/files/helpers/sanitize.py

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import functools
import bleach
from bs4 import BeautifulSoup
from bleach.css_sanitizer import CSSSanitizer
from bleach.linkifier import LinkifyFilter
from functools import partial
from .get import *
from os import path, environ
import re
from mistletoe import markdown
from json import loads, dump
from random import random, choice
import signal
import time
import requests
allowed_tags = ('b','blockquote','br','code','del','em','h1','h2','h3','h4','h5','h6','hr','i',
'li','ol','p','pre','strong','sub','sup','table','tbody','th','thead','td','tr','ul',
'marquee','a','span','ruby','rp','rt','spoiler','img','lite-youtube','video','audio','g')
allowed_styles = ['color', 'background-color', 'font-weight', 'text-align', 'filter',]
def allowed_attributes(tag, name, value):
if name == 'style': return True
if tag == 'marquee':
if name in ['direction', 'behavior', 'scrollamount']: return True
if name in {'height', 'width'}:
try: value = int(value.replace('px', ''))
except: return False
if 0 < value <= 250: return True
return False
if tag == 'a':
if name == 'href' and '\\' not in value and 'xn--' not in value:
return True
if name == 'rel' and value == 'nofollow noopener': return True
if name == 'target' and value == '_blank': return True
return False
if tag == 'img':
if name in ['src','data-src']: return is_safe_url(value)
if name == 'loading' and value == 'lazy': return True
if name == 'data-bs-toggle' and value == 'tooltip': return True
if name in ['g','b','glow'] and not value: return True
if name in ['alt','title']: return True
return False
if tag == 'lite-youtube':
if name == 'params' and value.startswith('autoplay=1&modestbranding=1'): return True
if name == 'videoid': return True
return False
if tag == 'video':
if name == 'controls' and value == '': return True
if name == 'preload' and value == 'none': return True
if name == 'src': return is_safe_url(value)
return False
if tag == 'audio':
if name == 'src': return is_safe_url(value)
if name == 'controls' and value == '': return True
if name == 'preload' and value == 'none': return True
return False
if tag == 'p':
if name == 'class' and value == 'mb-0': return True
return False
if tag == 'span':
if name == 'data-bs-toggle' and value == 'tooltip': return True
if name == 'title': return True
if name == 'alt': return True
return False
def build_url_re(protocols):
"""Builds the url regex used by linkifier
If you want a different set of tlds or allowed protocols, pass those in
and stomp on the existing ``url_re``::
from bleach import linkifier
my_url_re = linkifier.build_url_re(my_tlds_list, my_protocols)
linker = LinkifyFilter(url_re=my_url_re)
"""
return re.compile(
r"""\(*# Match any opening parentheses.
\b(?<![@.])(?:(?:{0}):/{{0,3}}(?:(?:\w+:)?\w+@)?)?# http://
([\w-]+\.)+(?:[A-Za-z]{{2,20}})(?:\:[0-9]+)?(?!\.\w)\b# xx.yy.tld(:##)?
(?:[/?][^#\s\{{\}}\|\\\^\[\]`<>"]*)?
# /path/zz (excluding "unsafe" chars from RFC 1738,
# except for ~, which happens in practice)
(?:\#[^#\s\|\\\^\[\]`<>"]*)?
# #hash (excluding "unsafe" chars from RFC 1738,
# except for ~, which happens in practice)
""".format("|".join(sorted(protocols))),
re.IGNORECASE | re.VERBOSE | re.UNICODE,
)
url_re = build_url_re(protocols=['http', 'https'])
def callback(attrs, new=False):
if (None, "href") not in attrs:
return # Incorrect <a> tag
href = attrs[(None, "href")]
# \ in href right after / makes most browsers ditch site hostname and allows for a host injection bypassing the check, see <a href="/\google.com">cool</a>
if "\\" in href or not ascii_only_regex.fullmatch(href):
attrs["_text"] = href # Laugh at this user
del attrs[(None, "href")] # Make unclickable and reset harmful payload
return attrs
if not href.startswith('/') and not href.startswith(f'{SITE_FULL}/'):
attrs[(None, "target")] = "_blank"
attrs[(None, "rel")] = "nofollow noopener"
return attrs
def render_emoji(html, regexp, golden, marseys_used, b=False):
emojis = list(regexp.finditer(html))
captured = set()
for i in emojis:
if i.group(0) in captured: continue
captured.add(i.group(0))
emoji = i.group(1).lower()
attrs = ''
if b: attrs += ' b'
if golden and len(emojis) <= 20 and ('marsey' in emoji or emoji in marseys_const2):
if random() < 0.0025: attrs += ' g'
elif random() < 0.00125: attrs += ' glow'
old = emoji
emoji = emoji.replace('!','').replace('#','')
if emoji == 'marseyrandom': emoji = choice(marseys_const2)
emoji_partial_pat = '<img loading="lazy" alt=":{0}:" src="{1}"{2}>'
emoji_partial = '<img loading="lazy" data-bs-toggle="tooltip" alt=":{0}:" title=":{0}:" src="{1}"{2}>'
emoji_html = None
if emoji.endswith('pat') and emoji != 'marseyunpettablepat':
if path.isfile(f"files/assets/images/emojis/{emoji.replace('pat','')}.webp"):
emoji_html = f'<span data-bs-toggle="tooltip" alt=":{old}:" title=":{old}:"><img src="/i/hand.webp">{emoji_partial_pat.format(old, f"/e/{emoji[:-3]}.webp", attrs)}</span>'
elif emoji.startswith('@'):
if u := get_user(emoji[1:-3], graceful=True):
emoji_html = f'<span data-bs-toggle="tooltip" alt=":{old}:" title=":{old}:"><img src="/i/hand.webp">{emoji_partial_pat.format(old, f"/pp/{u.id}", attrs)}</span>'
elif path.isfile(f'files/assets/images/emojis/{emoji}.webp'):
emoji_html = emoji_partial.format(old, f'/e/{emoji}.webp', attrs)
if emoji_html:
marseys_used.add(emoji)
html = re.sub(f'(?<!"){i.group(0)}', emoji_html, html)
return html
def with_sigalrm_timeout(timeout: int):
'Use SIGALRM to raise an exception if the function executes for longer than timeout seconds'
# while trying to test this using time.sleep I discovered that gunicorn does in fact do some
# async so if we timeout on that (or on a db op) then the process is crashed without returning
# a proper 500 error. Oh well.
def sig_handler(signum, frame):
print("Timeout!", flush=True)
raise Exception("Timeout")
def inner(func):
@functools.wraps(func)
def wrapped(*args, **kwargs):
signal.signal(signal.SIGALRM, sig_handler)
signal.alarm(timeout)
try:
return func(*args, **kwargs)
finally:
signal.alarm(0)
return wrapped
return inner
def sanitize_raw_title(sanitized):
if not sanitized: return ""
sanitized = sanitized.replace('\u200e','').replace('\u200b','').replace("\ufeff", "").replace("\r","").replace("\n", "")
sanitized = sanitized.strip()
return sanitized[:POST_TITLE_LENGTH_LIMIT]
def sanitize_raw_body(sanitized, is_post):
if not sanitized: return ""
sanitized = html_comment_regex.sub('', sanitized)
sanitized = sanitized.replace('\u200e','').replace('\u200b','').replace("\ufeff", "").replace("\r\n", "\n")
sanitized = sanitized.strip()
return sanitized[:POST_BODY_LENGTH_LIMIT if is_post else COMMENT_BODY_LENGTH_LIMIT]
@with_sigalrm_timeout(5)
def sanitize(sanitized, golden=True, limit_pings=0, showmore=True, count_marseys=False, torture=False):
sanitized = sanitized.strip()
sanitized = utm_regex.sub('', sanitized)
sanitized = utm_regex2.sub('', sanitized)
if torture:
sanitized = torture_ap(sanitized, g.v.username)
emoji = choice(['trumpjaktalking', 'reposthorse'])
sanitized += f'\n:#{emoji}:'
sanitized = normalize_url(sanitized)
if '```' not in sanitized and '<pre>' not in sanitized:
sanitized = linefeeds_regex.sub(r'\1\n\n\2', sanitized)
sanitized = greentext_regex.sub(r'\1<g>\>\2</g>', sanitized)
sanitized = image_regex.sub(r'\1![](\2)\5', sanitized)
sanitized = image_check_regex.sub(r'\1', sanitized)
sanitized = link_fix_regex.sub(r'\1https://\2', sanitized)
if FEATURES['MARKUP_COMMANDS']:
sanitized = command_regex.sub(command_regex_matcher, sanitized)
sanitized = markdown(sanitized)
sanitized = strikethrough_regex.sub(r'\1<del>\2</del>', sanitized)
# replacing zero width characters, overlines, fake colons
sanitized = sanitized.replace('\u200e','').replace('\u200b','').replace("\ufeff", "").replace("\u033f","").replace("\u0589", ":")
sanitized = reddit_regex.sub(r'\1<a href="https://old.reddit.com/\2" rel="nofollow noopener" target="_blank">/\2</a>', sanitized)
sanitized = sub_regex.sub(r'\1<a href="/\2">/\2</a>', sanitized)
v = getattr(g, 'v', None)
names = set(m.group(2) for m in mention_regex.finditer(sanitized))
if limit_pings and len(names) > limit_pings and not v.admin_level >= PERMS['POST_COMMENT_INFINITE_PINGS']: abort(406)
users_list = get_users(names, graceful=True)
users_dict = {}
for u in users_list:
users_dict[u.username.lower()] = u
if u.original_username:
users_dict[u.original_username.lower()] = u
def replacer(m):
u = users_dict.get(m.group(2).lower())
if not u:
return m.group(0)
return f'{m.group(1)}<a href="/id/{u.id}"><img loading="lazy" src="/pp/{u.id}">@{u.username}</a>'
sanitized = mention_regex.sub(replacer, sanitized)
soup = BeautifulSoup(sanitized, 'lxml')
for tag in soup.find_all("img"):
if tag.get("src") and not tag["src"].startswith('/pp/'):
if not is_safe_url(tag["src"]):
a = soup.new_tag("a", href=tag["src"], rel="nofollow noopener", target="_blank")
a.string = tag["src"]
tag.replace_with(a)
continue
tag["loading"] = "lazy"
tag["data-src"] = tag["src"]
tag["src"] = "/i/l.webp"
tag['alt'] = f'![]({tag["data-src"]})'
if tag.parent.name != 'a':
a = soup.new_tag("a", href=tag["data-src"])
if not is_site_url(a["href"]):
a["rel"] = "nofollow noopener"
a["target"] = "_blank"
tag = tag.replace_with(a)
a.append(tag)
for tag in soup.find_all("a"):
if not tag.contents or not str(tag.contents[0]).strip():
tag.extract()
if tag.get("href") and fishylinks_regex.fullmatch(str(tag.string)):
tag.string = tag["href"]
sanitized = str(soup)
sanitized = spoiler_regex.sub(r'<spoiler>\1</spoiler>', sanitized)
marseys_used = set()
emojis = list(emoji_regex.finditer(sanitized))
if len(emojis) > 20: golden = False
captured = []
for i in emojis:
if i.group(0) in captured: continue
captured.append(i.group(0))
old = i.group(0)
if 'marseylong1' in old or 'marseylong2' in old or 'marseyllama1' in old or 'marseyllama2' in old: new = old.lower().replace(">", " class='mb-0'>")
else: new = old.lower()
new = render_emoji(new, emoji_regex2, golden, marseys_used, True)
sanitized = sanitized.replace(old, new)
emojis = list(emoji_regex2.finditer(sanitized))
if len(emojis) > 20: golden = False
sanitized = render_emoji(sanitized, emoji_regex2, golden, marseys_used)
sanitized = sanitized.replace('&amp;','&')
if "https://youtube.com/watch?v=" in sanitized: sanitized = sanitized.replace("?t=", "&t=")
captured = []
for i in youtube_regex.finditer(sanitized):
if i.group(0) in captured: continue
captured.append(i.group(0))
params = parse_qs(urlparse(i.group(2)).query, keep_blank_values=True)
t = params.get('t', params.get('start', [0]))[0]
if isinstance(t, str): t = t.replace('s','')
htmlsource = f'{i.group(1)}<lite-youtube videoid="{i.group(3)}" params="autoplay=1&modestbranding=1'
if t: htmlsource += f'&start={t}'
htmlsource += '"></lite-youtube>'
sanitized = sanitized.replace(i.group(0), htmlsource)
sanitized = video_sub_regex.sub(r'\1<video controls preload="none" src="\2"></video>', sanitized)
sanitized = audio_sub_regex.sub(r'\1<audio controls preload="none" src="\2"></audio>', sanitized)
if count_marseys:
for marsey in g.db.query(Marsey).filter(Marsey.submitter_id==None, Marsey.name.in_(marseys_used)).all():
marsey.count += 1
g.db.add(marsey)
sanitized = sanitized.replace('<p></p>', '')
sanitized = sanitized.replace('<html><body>','').replace('</body></html>','')
css_sanitizer = CSSSanitizer(allowed_css_properties=allowed_styles)
sanitized = bleach.Cleaner(tags=allowed_tags,
attributes=allowed_attributes,
protocols=['http', 'https'],
css_sanitizer=css_sanitizer,
filters=[partial(LinkifyFilter, skip_tags=["pre"],
parse_email=False, callbacks=[callback], url_re=url_re)]
).clean(sanitized)
soup = BeautifulSoup(sanitized, 'lxml')
links = soup.find_all("a")
domain_list = set()
for link in links:
href = link.get("href")
if not href: continue
url = urlparse(href)
d = tldextract.extract(href).registered_domain + url.path
domain_list.add(d.lower())
banned_domains = g.db.query(BannedDomain).all()
for x in banned_domains:
for y in domain_list:
if y.startswith(x.domain):
abort(403, description=f'Remove the banned link "{x.domain}" and try again!\nReason for link ban: "{x.reason}"')
if '<pre>' not in sanitized:
sanitized = sanitized.replace('\n','')
if showmore and len(sanitized) > 3500:
sanitized = showmore_regex.sub(r'\1<p><button class="showmore" onclick="showmore()">SHOW MORE</button></p><d class="d-none">\2</d>', sanitized, count=1)
return sanitized.strip()
def allowed_attributes_emojis(tag, name, value):
if tag == 'img':
if name == 'src' and value.startswith('/') and '\\' not in value: return True
if name == 'loading' and value == 'lazy': return True
if name == 'data-bs-toggle' and value == 'tooltip': return True
if name in ['g','glow'] and not value: return True
if name in ['alt','title']: return True
if tag == 'span':
if name == 'data-bs-toggle' and value == 'tooltip': return True
if name == 'title': return True
if name == 'alt': return True
return False
return False
@with_sigalrm_timeout(1)
def filter_emojis_only(title, golden=True, count_marseys=False, graceful=False, torture=False):
title = title.strip()
if torture:
title = torture_ap(title, g.v.username)
title = title.replace('','').replace('','').replace("\ufeff", "").replace("𒐪","").replace("\n", "").replace("\r", "").replace("\t", "").replace("&", "&amp;").replace('<','&lt;').replace('>','&gt;').replace('"', '&quot;').replace("'", "&#039;").strip()
marseys_used = set()
title = render_emoji(title, emoji_regex3, golden, marseys_used)
if count_marseys:
for marsey in g.db.query(Marsey).filter(Marsey.submitter_id==None, Marsey.name.in_(marseys_used)).all():
marsey.count += 1
g.db.add(marsey)
title = strikethrough_regex.sub(r'\1<del>\2</del>', title)
title = bleach.clean(title, tags=['img','del','span'], attributes=allowed_attributes_emojis, protocols=['http','https']).replace('\n','').strip()
if len(title) > POST_TITLE_HTML_LENGTH_LIMIT and not graceful: abort(400)
else: return title
def normalize_url(url):
url = reddit_domain_regex.sub(r'\1https://old.reddit.com/\3/', url)
url = url.replace("https://youtu.be/", "https://youtube.com/watch?v=") \
.replace("https://music.youtube.com/watch?v=", "https://youtube.com/watch?v=") \
.replace("https://www.youtube.com", "https://youtube.com") \
.replace("https://youtube.com/shorts/", "https://youtube.com/watch?v=") \
.replace("https://youtube.com/v/", "https://youtube.com/watch?v=") \
.replace("https://mobile.twitter.com", "https://twitter.com") \
.replace("https://m.facebook.com", "https://facebook.com") \
.replace("https://m.wikipedia.org", "https://wikipedia.org") \
.replace("https://m.youtube.com", "https://youtube.com") \
.replace("https://www.twitter.com", "https://twitter.com") \
.replace("https://www.instagram.com", "https://instagram.com") \
.replace("https://www.tiktok.com", "https://tiktok.com") \
.replace("https://www.streamable.com", "https://streamable.com") \
.replace("https://streamable.com/", "https://streamable.com/e/") \
.replace("https://streamable.com/e/e/", "https://streamable.com/e/") \
.replace("https://search.marsey.cat/#", "https://camas.unddit.com/#") \
.replace("https://imgur.com/", "https://i.imgur.com/") \
.replace("https://nitter.net/", "https://twitter.com/") \
.replace("https://nitter.42l.fr/", "https://twitter.com/") \
.replace("https://nitter.lacontrevoie.fr/", "https://twitter.com/")
url = imgur_regex.sub(r'\1_d.webp?maxwidth=9999&fidelity=high', url)
url = giphy_regex.sub(r'\1.webp', url)
return url
def validate_css(css):
if '@import' in css:
return False, "@import statements are not allowed!"
for i in css_url_regex.finditer(css):
url = i.group(1)
if not is_safe_url(url):
domain = tldextract.extract(url).registered_domain
return False, f"The domain '{domain}' is not allowed, please use one of these domains\n\n{approved_embed_hosts}."
return True, ""