Setting encryption as required in security flags was broken.
For example (to require all mounts to be encrypted by setting):
"echo 0x400c5 > /proc/fs/cifs/SecurityFlags"
Would return "Invalid argument" and log "Unsupported security flags"
This patch fixes that (e.g. allowing overriding the default for
SecurityFlags 0x00c5, including 0x40000 to require seal, ie
SMB3.1.1 encryption) so now that works and forces encryption
on subsequent mounts.
Acked-by: Bharath SM <bharathsm@xxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
diff --git a/Documentation/admin-guide/cifs/usage.rst b/Documentation/admin-guide/cifs/usage.rst
index fd4b56c0996f..c09674a75a9e 100644
--- a/Documentation/admin-guide/cifs/usage.rst
+++ b/Documentation/admin-guide/cifs/usage.rst
@@ -742,7 +742,7 @@ SecurityFlags Flags which control security negotiation and
may use NTLMSSP 0x00080
must use NTLMSSP 0x80080
seal (packet encryption) 0x00040
- must seal (not implemented yet) 0x40040
+ must seal 0x40040
cifsFYI If set to non-zero value, additional debug information
will be logged to the system error log. This field
diff --git a/fs/smb/client/cifs_debug.c b/fs/smb/client/cifs_debug.c
index c71ae5c04306..4a20e92474b2 100644
--- a/fs/smb/client/cifs_debug.c
+++ b/fs/smb/client/cifs_debug.c
@@ -1072,7 +1072,7 @@ static int cifs_security_flags_proc_open(struct inode *inode, struct file *file)
static void
cifs_security_flags_handle_must_flags(unsigned int *flags)
{
- unsigned int signflags = *flags & CIFSSEC_MUST_SIGN;
+ unsigned int signflags = *flags & (CIFSSEC_MUST_SIGN | CIFSSEC_MUST_SEAL);
if ((*flags & CIFSSEC_MUST_KRB5) == CIFSSEC_MUST_KRB5)
*flags = CIFSSEC_MUST_KRB5;
diff --git a/fs/smb/client/cifsglob.h b/fs/smb/client/cifsglob.h
index f6d1f075987f..b9f46d29a441 100644
--- a/fs/smb/client/cifsglob.h
+++ b/fs/smb/client/cifsglob.h
@@ -1881,7 +1881,7 @@ static inline bool is_replayable_error(int error)
#define CIFSSEC_MAY_SIGN 0x00001
#define CIFSSEC_MAY_NTLMV2 0x00004
#define CIFSSEC_MAY_KRB5 0x00008
-#define CIFSSEC_MAY_SEAL 0x00040 /* not supported yet */
+#define CIFSSEC_MAY_SEAL 0x00040
#define CIFSSEC_MAY_NTLMSSP 0x00080 /* raw ntlmssp with ntlmv2 */
#define CIFSSEC_MUST_SIGN 0x01001
@@ -1891,11 +1891,11 @@ require use of the stronger protocol */
#define CIFSSEC_MUST_NTLMV2 0x04004
#define CIFSSEC_MUST_KRB5 0x08008
#ifdef CONFIG_CIFS_UPCALL
-#define CIFSSEC_MASK 0x8F08F /* flags supported if no weak allowed */
+#define CIFSSEC_MASK 0xCF0CF /* flags supported if no weak allowed */
#else
-#define CIFSSEC_MASK 0x87087 /* flags supported if no weak allowed */
+#define CIFSSEC_MASK 0xC70C7 /* flags supported if no weak allowed */
#endif /* UPCALL */
-#define CIFSSEC_MUST_SEAL 0x40040 /* not supported yet */
+#define CIFSSEC_MUST_SEAL 0x40040
#define CIFSSEC_MUST_NTLMSSP 0x80080 /* raw ntlmssp with ntlmv2 */
#define CIFSSEC_DEF (CIFSSEC_MAY_SIGN | CIFSSEC_MAY_NTLMV2 | CIFSSEC_MAY_NTLMSSP | CIFSSEC_MAY_SEAL)
diff --git a/fs/smb/client/smb2pdu.c b/fs/smb/client/smb2pdu.c
index 9a06b5594669..83facb54276a 100644
--- a/fs/smb/client/smb2pdu.c
+++ b/fs/smb/client/smb2pdu.c
@@ -82,6 +82,9 @@ int smb3_encryption_required(const struct cifs_tcon *tcon)
if (tcon->seal &&
(tcon->ses->server->capabilities & SMB2_GLOBAL_CAP_ENCRYPTION))
return 1;
+ if (((global_secflags & CIFSSEC_MUST_SEAL) == CIFSSEC_MUST_SEAL) &&
+ (tcon->ses->server->capabilities & SMB2_GLOBAL_CAP_ENCRYPTION))
+ return 1;
return 0;
}
