firewall.py: add comments about sysctl problems.

This commit is contained in:
Avery Pennarun 2012-01-08 19:13:39 -05:00
parent d9f761a8a3
commit e737f4b944

View File

@ -270,6 +270,12 @@ def do_ipfw(port, dnsport, subnets):
if subnets or dnsport:
sysctl_set('net.inet.ip.fw.enable', 1)
# This seems to be needed on MacOS 10.6 and 10.7. For more
# information, see:
# http://groups.google.com/group/sshuttle/browse_thread/thread/bc32562e17987b25/6d3aa2bb30a1edab
# and
# http://serverfault.com/questions/138622/transparent-proxying-leaves-sockets-with-syn-rcvd-in-macos-x-10-6-snow-leopard
changeflag = sysctl_set('net.inet.ip.scopedroute', 0, permanent=True)
if changeflag == SUCCESS:
log("\n"
@ -283,6 +289,10 @@ def do_ipfw(port, dnsport, subnets):
"permanent; you only have to do this once.\n\n")
sys.exit(1)
elif changeflag == FAILED:
# On MacOS 10.7, the scopedroute sysctl became read-only, so
# we have to fix it using a kernel boot parameter instead,
# which requires rebooting. For more, see:
# http://groups.google.com/group/sshuttle/browse_thread/thread/a42505ca33e1de80/e5e8f3e5a92d25f7
log('Updating kernel boot flags.\n')
defaults_write_kernel_flag('net.inet.ip.scopedroute', 0)
log("\n"