File Services
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Titan SiliconServer
The following security modes are supported:
Note:
FTP clients follow either the Windows or the UNIX security model
depending on how they were authenticated. FTP clients authenticated by an
NT domain appear as CIFS clients for the purpose of security. Similarly, FTP
clients authenticated though NIS appear as NFS clients.
With both Mixed and UNIX security mode it is necessary to
configure user and group mappings
between UNIX and Windows. However, NFS users do not require security mappings when in
UNIX mode.
Mixed Security Mode
Titan’s mixed security mode supports both Windows and UNIX security definitions. Security is
set up uniquely on each file (or directory), depending on which user created the file (or
directory), or last took ownership of the file (or directory). If a Windows user owned the file (or
directory), the security definition will be CIFS native and subject to Windows security rules. If,
on the other hand, the file belongs to a UNIX user, the security definition will be NFS native and
subject to UNIX security rules.
CIFS Access to Native CIFS Files
When a CIFS client tries to access a
native
file, one with Windows security information, the
server checks the user information against the file’s security information to determine whether
or not an operation is permissible.
Mode
Clients
Notes
Mixed
CIFS
The server authenticates CIFS sessions by communicating with a domain
controller, which returns user security information. Accesses to files
that have NT permissions are checked against this security information.
If a file has UNIX permissions, the security information is mapped to an
equivalent UNIX identity and checked against the file permissions.
NFS
A client user's unauthenticated UNIX identity (a user ID and one or more
group IDs) accompanies each NFS request. Accesses to files that have
UNIX-only permissions are checked against this. If a file has NT
permissions, the identity is mapped to an equivalent NT identity and
checked against the file permissions.
UNIX
CIFS
The server authenticates CIFS sessions by communicating with a domain
controller, which returns user security information. All files have UNIX
permissions, so the security information is mapped to an equivalent
UNIX identity and checked against the file permissions.
NFS
NFS clients are trusted to supply the requesting user's UNIX identity
with every request. This identity is checked against UNIX per-file
permissions to determine whether or not an operation is permissible.
