From 36803da8f9e9fb2b646d49584384c938c1e706d7 Mon Sep 17 00:00:00 2001 From: John Terpstra Date: Fri, 4 Apr 2003 05:19:59 +0000 Subject: Superceded files (This used to be commit 8db911098513f5cab3e423279f743c04f3bd2c27) --- docs/docbook/projdoc/ENCRYPTION.sgml | 189 ----------------------------------- 1 file changed, 189 deletions(-) delete mode 100644 docs/docbook/projdoc/ENCRYPTION.sgml (limited to 'docs/docbook/projdoc/ENCRYPTION.sgml') diff --git a/docs/docbook/projdoc/ENCRYPTION.sgml b/docs/docbook/projdoc/ENCRYPTION.sgml deleted file mode 100644 index f903d7d334..0000000000 --- a/docs/docbook/projdoc/ENCRYPTION.sgml +++ /dev/null @@ -1,189 +0,0 @@ - - - - - - JeremyAllison - - Samba Team -
- jra@samba.org -
- - - - - JelmerVernooij - - Samba Team -
- jelmer@samba.org -
- - - - 4 November 2002 - - -LanMan and NT Password Encryption in Samba - - - - Introduction - - Newer windows clients send encrypted passwords over - the wire, instead of plain text passwords. The newest clients - will only send encrypted passwords and refuse to send plain text - passwords, unless their registry is tweaked. - - These passwords can't be converted to unix style encrypted - passwords. Because of that you can't use the standard unix - user database, and you have to store the Lanman and NT hashes - somewhere else. For more information, see the documentation - about the passdb backend = parameter. - - - - - - Important Notes About Security - - The unix and SMB password encryption techniques seem similar - on the surface. This similarity is, however, only skin deep. The unix - scheme typically sends clear text passwords over the network when - logging in. This is bad. The SMB encryption scheme never sends the - cleartext password over the network but it does store the 16 byte - hashed values on disk. This is also bad. Why? Because the 16 byte hashed - values are a "password equivalent". You cannot derive the user's - password from them, but they could potentially be used in a modified - client to gain access to a server. This would require considerable - technical knowledge on behalf of the attacker but is perfectly possible. - You should thus treat the smbpasswd file as though it contained the - cleartext passwords of all your users. Its contents must be kept - secret, and the file should be protected accordingly. - - Ideally we would like a password scheme which neither requires - plain text passwords on the net or on disk. Unfortunately this - is not available as Samba is stuck with being compatible with - other SMB systems (WinNT, WfWg, Win95 etc). - - - Note that Windows NT 4.0 Service pack 3 changed the - default for permissible authentication so that plaintext - passwords are never sent over the wire. - The solution to this is either to switch to encrypted passwords - with Samba or edit the Windows NT registry to re-enable plaintext - passwords. See the document WinNT.txt for details on how to do - this. - - Other Microsoft operating systems which also exhibit - this behavior includes - - - MS DOS Network client 3.0 with - the basic network redirector installed - - Windows 95 with the network redirector - update installed - - Windows 98 [se] - - Windows 2000 - - - Note :All current release of - Microsoft SMB/CIFS clients support authentication via the - SMB Challenge/Response mechanism described here. Enabling - clear text authentication does not disable the ability - of the client to participate in encrypted authentication. - - - - Advantages of SMB Encryption - - - plain text passwords are not passed across - the network. Someone using a network sniffer cannot just - record passwords going to the SMB server. - - - WinNT doesn't like talking to a server - that isn't using SMB encrypted passwords. It will refuse - to browse the server if the server is also in user level - security mode. It will insist on prompting the user for the - password on each connection, which is very annoying. The - only things you can do to stop this is to use SMB encryption. - - - - - - - Advantages of non-encrypted passwords - - - plain text passwords are not kept - on disk. - - uses same password file as other unix - services such as login and ftp - - you are probably already using other - services (such as telnet and ftp) which send plain text - passwords over the net, so sending them for SMB isn't - such a big deal. - - - - - - - The smbpasswd Command - - The smbpasswd command maintains the two 32 byte password fields - in the smbpasswd file. If you wish to make it similar to the unix - passwd or yppasswd programs, - install it in /usr/local/samba/bin/ (or your - main Samba binary directory). - - smbpasswd now works in a client-server mode - where it contacts the local smbd to change the user's password on its - behalf. This has enormous benefits - as follows. - - smbpasswd now has the capability - to change passwords on Windows NT servers (this only works when - the request is sent to the NT Primary Domain Controller if you - are changing an NT Domain user's password). - - To run smbpasswd as a normal user just type : - - $ smbpasswd - Old SMB password: <type old value here - - or hit return if there was no old password> - New SMB Password: <type new value> - - Repeat New SMB Password: <re-type new value - - - If the old value does not match the current value stored for - that user, or the two new values do not match each other, then the - password will not be changed. - - If invoked by an ordinary user it will only allow the user - to change his or her own Samba password. - - If run by the root user smbpasswd may take an optional - argument, specifying the user name whose SMB password you wish to - change. Note that when run as root smbpasswd does not prompt for - or check the old password value, thus allowing root to set passwords - for users who have forgotten their passwords. - - smbpasswd is designed to work in the same way - and be familiar to UNIX users who use the passwd or - yppasswd commands. - - For more details on using smbpasswd refer - to the man page which will always be the definitive reference. - - - -- cgit