smbclient 3.5 can't connect to a Windows 7 server using NTLMv2 where smbclient 3.3, 3.4 and 3.6 can

[Blohm, Guntram (I/FP-37, extern)]

Found the bug, though it took me a while.

In samba version 3.4, source3/libsmb/smbencrypt.c says

        if (!ntv2_owf_gen(nt_hash, user, domain, False, ntlm_v2_hash)) {

the False tells ntv2_owf_gen not to uppercase the domain name.

Samba version 3.5 moves the file to libcli/auth/smbencrypt.c and changes that line to

        if (!ntv2_owf_gen(nt_hash, user, domain, true, ntlm_v2_hash)) {

and version 3.6 doesn't change anything there.


When the domain/workgroup name is fetched from the command line (in source3/libsmb/cliconnect.c), 3.4 has:

        if ((p=strchr_m(user2,'\\')) || (p=strchr_m(user2,'/')) ||
            (p=strchr_m(user2,*lp_winbind_separator()))) {
                *p = 0;
                user = p+1;
                workgroup = user2;
        }

which does not change in 3.5, but 3.6 uses

        if ((p=strchr_m(user2,'\\')) || (p=strchr_m(user2,'/')) ||
            (p=strchr_m(user2,*lp_winbind_separator()))) {
                *p = 0;
                user = p+1;
                strupper_m(user2);
                workgroup = user2;
        }

So basically the problem is: version 3.4 (and below) passes a lowercase version (to be exact: same case that was given on the command line) of the workgroup name to the encryption subsystem, and also uses this lowercase version in the plain text part of the NTLMSSP message. 3.5 uses an uppercase workgroup name for encryption, but still passes the lowercase version of the workgroup in the plain text part, causing the NTLMv2 authentication to fail (at least against Win7 as server). 3.6 always uppercases the workgroup name, so NTLMv2 authentication works again.

I'd propose to copy the

                strupper_m(user2);

line from 3.6 to 3.5, or are there any reasons not to do this? In the meanwhile, the workaround could be using all uppercase domain names on the command line (which is what I'm doing right now).

Guntram Blohm