[CIFS] Allow setting mode via cifs acl

Requires cifsacl mount flag to be on and CIFS_EXPERIMENTAL enabled

CC: Shirish Pargaonkar <shirishp@us.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>

1 files changed, 65 insertions, 0 deletions

diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index 618542b8ce0b..9409524e4bf8 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -3156,6 +3156,71 @@ qsec_out:
 /*      cifs_small_buf_release(pSMB); */ /* Freed earlier now in SendReceive2 */
         return rc;
 }
+
+int
+CIFSSMBSetCIFSACL(const int xid, struct cifsTconInfo *tcon, __u16 fid,
+                        struct cifs_ntsd *pntsd, __u32 acllen)
+{
+        __u16 byte_count, param_count, data_count, param_offset, data_offset;
+        int rc = 0;
+        int bytes_returned = 0;
+        SET_SEC_DESC_REQ *pSMB = NULL;
+        NTRANSACT_RSP *pSMBr = NULL;
+
+setCifsAclRetry:
+        rc = smb_init(SMB_COM_NT_TRANSACT, 19, tcon, (void **) &pSMB,
+                        (void **) &pSMBr);
+        if (rc)
+                        return (rc);
+
+        pSMB->MaxSetupCount = 0;
+        pSMB->Reserved = 0;
+
+        param_count = 8;
+        param_offset = offsetof(struct smb_com_transaction_ssec_req, Fid) - 4;
+        data_count = acllen;
+        data_offset = param_offset + param_count;
+        byte_count = 3 /* pad */  + param_count;
+
+        pSMB->DataCount = cpu_to_le32(data_count);
+        pSMB->TotalDataCount = pSMB->DataCount;
+        pSMB->MaxParameterCount = cpu_to_le32(4);
+        pSMB->MaxDataCount = cpu_to_le32(16384);
+        pSMB->ParameterCount = cpu_to_le32(param_count);
+        pSMB->ParameterOffset = cpu_to_le32(param_offset);
+        pSMB->TotalParameterCount = pSMB->ParameterCount;
+        pSMB->DataOffset = cpu_to_le32(data_offset);
+        pSMB->SetupCount = 0;
+        pSMB->SubCommand = cpu_to_le16(NT_TRANSACT_SET_SECURITY_DESC);
+        pSMB->ByteCount = cpu_to_le16(byte_count+data_count);
+
+        pSMB->Fid = fid; /* file handle always le */
+        pSMB->Reserved2 = 0;
+        pSMB->AclFlags = cpu_to_le32(CIFS_ACL_DACL);
+
+        if (pntsd && acllen) {
+                memcpy((char *) &pSMBr->hdr.Protocol + data_offset,
+                        (char *) pntsd,
+                        acllen);
+                pSMB->hdr.smb_buf_length += (byte_count + data_count);
+
+        } else
+                pSMB->hdr.smb_buf_length += byte_count;
+
+        rc = SendReceive(xid, tcon->ses, (struct smb_hdr *) pSMB,
+                (struct smb_hdr *) pSMBr, &bytes_returned, 0);
+
+        cFYI(1, ("SetCIFSACL bytes_returned: %d, rc: %d", bytes_returned, rc));
+        if (rc)
+                cFYI(1, ("Set CIFS ACL returned %d", rc));
+        cifs_buf_release(pSMB);
+
+        if (rc == -EAGAIN)
+                goto setCifsAclRetry;
+
+        return (rc);
+}
+
 #endif /* CONFIG_CIFS_EXPERIMENTAL */
 
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