CpServiceSPb .
2015-Jan-11 13:55 UTC
[Samba] Samba4 and 0.0.0.0:137 and 0.0.0.0:138 opened, why ? How do close it ?
I have Samba4 4.1.14 (built from sources) installed at Ubuntu 14.04 LTS x32 and acting as Standalone server at the time. Here are 3 faces at Ubuntu: lo, lan and wan. There are lines: bind interfaces only = yes interfaces = lo lan0 in smb.conf But netstat -tulpn shows 0.0.0.0 binded address: tcp 0 0 192.168.0.254:139 0.0.0.0:* LISTEN smbd udp 0 0 192.168.0.255:137 0.0.0.0:* nmbd udp 0 0 192.168.0.254:137 0.0.0.0:* nmbd *udp 0 0 0.0.0.0:137 <http://0.0.0.0:137> 0.0.0.0:* nmbd* udp 0 0 192.168.0.255:138 0.0.0.0:* nmbd udp 0 0 192.168.0.254:138 0.0.0.0:* nmbd *udp 0 0 0.0.0.0:138 <http://0.0.0.0:138> 0.0.0.0:* nmbd* I don'n like *udp 0 0 0.0.0.0:port *at all ! Why is it so ? How is it possible to close via Samba conf ?
Marc Muehlfeld
2015-Jan-11 14:24 UTC
[Samba] Samba4 and 0.0.0.0:137 and 0.0.0.0:138 opened, why ? How do close it ?
Hello, Am 11.01.2015 um 14:55 schrieb CpServiceSPb .:> Here are 3 faces at Ubuntu: lo, lan and wan. > There are lines: > bind interfaces only = yes > interfaces = lo lan0 > in smb.conf > > But netstat -tulpn shows 0.0.0.0 binded address: > tcp 0 0 192.168.0.254:139 0.0.0.0:* > LISTEN smbd > udp 0 0 192.168.0.255:137 0.0.0.0:* > nmbd > udp 0 0 192.168.0.254:137 0.0.0.0:* > nmbd > *udp 0 0 0.0.0.0:137 <http://0.0.0.0:137> > 0.0.0.0:* nmbd* > udp 0 0 192.168.0.255:138 0.0.0.0:* > nmbd > udp 0 0 192.168.0.254:138 0.0.0.0:* > nmbd > *udp 0 0 0.0.0.0:138 <http://0.0.0.0:138> > 0.0.0.0:* nmbd* > > I don'n like *udp 0 0 0.0.0.0:port *at all ! > > Why is it so ?The smb.conf man page answers this question ('bind interfaces only'): ... nmbd also binds to the "all addresses" interface (0.0.0.0) on ports 137 and 138 for the purposes of reading broadcast messages. If this option is not set then nmbd will service name requests on all of these sockets. If bind interfaces only is set then nmbd will check the source address of any packets coming in on the broadcast sockets and discard any that don't match the broadcast addresses of the interfaces in the interfaces parameter list. ... Regards, Marc
CpServiceSPb .
2015-Jan-11 14:46 UTC
[Samba] Samba4 and 0.0.0.0:137 and 0.0.0.0:138 opened, why ? How do close it ?
Thanks for this answer. As I understood, for example if parameter bind interfaces only = yes is and interfaces = lan0 (192.168.0.254) is and if broadcast packet goes from 95.95.95.14 such packet will be dropped (in other words) ? Am I right ? And other thing. Why is 192.168.0.255 (network broadcast) opened for ? May be exact such address (network broadcast) is inbtended for receiving broadcasts ? Within exact subnet but 0.0.0.0 is for all subnets ? And is it possible to set off 0.0.0.0 via smb.conf ? 2015-01-11 17:24 GMT+03:00 Marc Muehlfeld <mmuehlfeld at samba.org>:> Hello, > > Am 11.01.2015 um 14:55 schrieb CpServiceSPb .: > > Here are 3 faces at Ubuntu: lo, lan and wan. > > There are lines: > > bind interfaces only = yes > > interfaces = lo lan0 > > in smb.conf > > > > But netstat -tulpn shows 0.0.0.0 binded address: > > tcp 0 0 192.168.0.254:139 0.0.0.0:* > > LISTEN smbd > > udp 0 0 192.168.0.255:137 0.0.0.0:* > > nmbd > > udp 0 0 192.168.0.254:137 0.0.0.0:* > > nmbd > > *udp 0 0 0.0.0.0:137 <http://0.0.0.0:137> > > 0.0.0.0:* nmbd* > > udp 0 0 192.168.0.255:138 0.0.0.0:* > > nmbd > > udp 0 0 192.168.0.254:138 0.0.0.0:* > > nmbd > > *udp 0 0 0.0.0.0:138 <http://0.0.0.0:138> > > 0.0.0.0:* nmbd* > > > > I don'n like *udp 0 0 0.0.0.0:port *at all ! > > > > Why is it so ? > > > The smb.conf man page answers this question ('bind interfaces only'): > > ... nmbd also binds to the "all addresses" interface (0.0.0.0) on ports > 137 and 138 for the purposes of reading broadcast messages. If this > option is not set then nmbd will service name requests on all of these > sockets. If bind interfaces only is set then nmbd will check the source > address of any packets coming in on the broadcast sockets and discard > any that don't match the broadcast addresses of the interfaces in the > interfaces parameter list. ... > > > > > Regards, > Marc >