Created attachment 10434 [details] Capture of smbclient to Samba 4.1.12 showing this. Attached is a capture from smbclient on a Samba 4.1.12 system against the same system (on the loopback interface). The NegProt Request offers a bunch of dialects, including NT LANMAN 1.0 and NT LM 0.12. Samba selects NT LANMAN 1.0 rather than the NT LM 0.12 I would have expected.
Hey Richard. Smbclient sends List of dialects in favorite dialect at top & least fav at bottom in Negotiation_Protocol_request message. SMB server sends highest dialect it supports from List. From samba code /* List of supported protocols, most desired first */ } supported_protocols[] = { {"SMB 2.???", "SMB2_FF", reply_smb20ff, PROTOCOL_SMB2_10}, {"SMB 2.002", "SMB2_02", reply_smb2002, PROTOCOL_SMB2_02}, {"NT LANMAN 1.0", "NT1", reply_nt1, PROTOCOL_NT1}, {"NT LM 0.12", "NT1", reply_nt1, PROTOCOL_NT1}, {"POSIX 2", "NT1", reply_nt1, PROTOCOL_NT1}, {"LANMAN2.1", "LANMAN2", reply_lanman2, PROTOCOL_LANMAN2}, {"LM1.2X002", "LANMAN2", reply_lanman2, PROTOCOL_LANMAN2}, {"Samba", "LANMAN2", reply_lanman2, PROTOCOL_LANMAN2}, {"DOS LM1.2X002", "LANMAN2", reply_lanman2, PROTOCOL_LANMAN2}, {"LANMAN1.0", "LANMAN1", reply_lanman1, PROTOCOL_LANMAN1}, {"MICROSOFT NETWORKS 3.0", "LANMAN1", reply_lanman1, PROTOCOL_LANMAN1}, {NULL,NULL,NULL,0}, }; So in this case, NT LANMAN 1.0 is higher wrt NT LM 0.12 and hence selected.