Merge pull request #4724 from mnin/master

[Netfilter] Fix creating endless SNAT rules for ipv4
This commit is contained in:
Niklas Meyer 2022-10-06 12:18:23 +02:00 committed by GitHub
commit 9fb346751c
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@ -252,7 +252,7 @@ def permBan(net, unban=False):
if rule not in chain.rules and not unban:
logCrit('Add host/network %s to blacklist' % net)
chain.insert_rule(rule)
r.hset('F2B_PERM_BANS', '%s' % net, int(round(time.time())))
r.hset('F2B_PERM_BANS', '%s' % net, int(round(time.time())))
elif rule in chain.rules and unban:
logCrit('Remove host/network %s from blacklist' % net)
chain.delete_rule(rule)
@ -267,7 +267,7 @@ def permBan(net, unban=False):
if rule not in chain.rules and not unban:
logCrit('Add host/network %s to blacklist' % net)
chain.insert_rule(rule)
r.hset('F2B_PERM_BANS', '%s' % net, int(round(time.time())))
r.hset('F2B_PERM_BANS', '%s' % net, int(round(time.time())))
elif rule in chain.rules and unban:
logCrit('Remove host/network %s from blacklist' % net)
chain.delete_rule(rule)
@ -346,6 +346,8 @@ def snat4(snat_target):
rule.dst = '!' + rule.src
target = rule.create_target("SNAT")
target.to_source = snat_target
match = rule.create_match("comment")
match.comment = f'{int(round(time.time()))}'
return rule
while not quit_now:
@ -356,19 +358,26 @@ def snat4(snat_target):
table.refresh()
chain = iptc.Chain(table, 'POSTROUTING')
table.autocommit = False
if get_snat4_rule() not in chain.rules:
logCrit('Added POSTROUTING rule for source network %s to SNAT target %s' % (get_snat4_rule().src, snat_target))
chain.insert_rule(get_snat4_rule())
table.commit()
else:
for position, item in enumerate(chain.rules):
if item == get_snat4_rule():
if position != 0:
chain.delete_rule(get_snat4_rule())
table.commit()
new_rule = get_snat4_rule()
for position, rule in enumerate(chain.rules):
match = all((
new_rule.get_src() == rule.get_src(),
new_rule.get_dst() == rule.get_dst(),
new_rule.target.parameters == rule.target.parameters,
new_rule.target.name == rule.target.name
))
if position == 0:
if not match:
logInfo(f'Added POSTROUTING rule for source network {new_rule.src} to SNAT target {snat_target}')
chain.insert_rule(new_rule)
else:
if match:
logInfo(f'Remove rule for source network {new_rule.src} to SNAT target {snat_target} from POSTROUTING chain at position {position}')
chain.delete_rule(rule)
table.commit()
table.autocommit = True
except:
print('Error running SNAT4, retrying...')
print('Error running SNAT4, retrying...')
def snat6(snat_target):
global lock
@ -402,7 +411,7 @@ def snat6(snat_target):
table.commit()
table.autocommit = True
except:
print('Error running SNAT6, retrying...')
print('Error running SNAT6, retrying...')
def autopurge():
while not quit_now:
@ -468,7 +477,7 @@ def whitelistUpdate():
if Counter(new_whitelist) != Counter(WHITELIST):
WHITELIST = new_whitelist
logInfo('Whitelist was changed, it has %s entries' % len(WHITELIST))
time.sleep(60.0 - ((time.time() - start_time) % 60.0))
time.sleep(60.0 - ((time.time() - start_time) % 60.0))
def blacklistUpdate():
global quit_now
@ -479,7 +488,7 @@ def blacklistUpdate():
new_blacklist = []
if list:
new_blacklist = genNetworkList(list)
if Counter(new_blacklist) != Counter(BLACKLIST):
if Counter(new_blacklist) != Counter(BLACKLIST):
addban = set(new_blacklist).difference(BLACKLIST)
delban = set(BLACKLIST).difference(new_blacklist)
BLACKLIST = new_blacklist
@ -490,7 +499,7 @@ def blacklistUpdate():
if delban:
for net in delban:
permBan(net=net, unban=True)
time.sleep(60.0 - ((time.time() - start_time) % 60.0))
time.sleep(60.0 - ((time.time() - start_time) % 60.0))
def initChain():
# Is called before threads start, no locking