cifs: Fix broken sec=ntlmv2/i sec option (try #2)
Fix sec=ntlmv2/i authentication option during mount of Samba shares.
cifs client was coding ntlmv2 response incorrectly.
All that is needed in temp as specified in MS-NLMP seciton 3.3.2
"Define ComputeResponse(NegFlg, ResponseKeyNT, ResponseKeyLM,
CHALLENGE_MESSAGE.ServerChallenge, ClientChallenge, Time, ServerName)
as
Set temp to ConcatenationOf(Responserversion, HiResponserversion,
Z(6), Time, ClientChallenge, Z(4), ServerName, Z(4)"
is MsvAvNbDomainName.
For sec=ntlmsspi, build_av_pair is not used, a blob is plucked from
type 2 response sent by the server to use in authentication.
I tested sec=ntlmv2/i and sec=ntlmssp/i mount options against
Samba (3.6) and Windows - XP, 2003 Server and 7.
They all worked.
Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c
index e76bfeb..30acd22 100644
--- a/fs/cifs/cifsencrypt.c
+++ b/fs/cifs/cifsencrypt.c
@@ -351,9 +351,7 @@
build_avpair_blob(struct cifs_ses *ses, const struct nls_table *nls_cp)
{
unsigned int dlen;
- unsigned int wlen;
- unsigned int size = 6 * sizeof(struct ntlmssp2_name);
- __le64 curtime;
+ unsigned int size = 2 * sizeof(struct ntlmssp2_name);
char *defdmname = "WORKGROUP";
unsigned char *blobptr;
struct ntlmssp2_name *attrptr;
@@ -365,15 +363,14 @@
}
dlen = strlen(ses->domainName);
- wlen = strlen(ses->server->hostname);
- /* The length of this blob is a size which is
- * six times the size of a structure which holds name/size +
- * two times the unicode length of a domain name +
- * two times the unicode length of a server name +
- * size of a timestamp (which is 8 bytes).
+ /*
+ * The length of this blob is two times the size of a
+ * structure (av pair) which holds name/size
+ * ( for NTLMSSP_AV_NB_DOMAIN_NAME followed by NTLMSSP_AV_EOL ) +
+ * unicode length of a netbios domain name
*/
- ses->auth_key.len = size + 2 * (2 * dlen) + 2 * (2 * wlen) + 8;
+ ses->auth_key.len = size + 2 * dlen;
ses->auth_key.response = kzalloc(ses->auth_key.len, GFP_KERNEL);
if (!ses->auth_key.response) {
ses->auth_key.len = 0;
@@ -384,44 +381,15 @@
blobptr = ses->auth_key.response;
attrptr = (struct ntlmssp2_name *) blobptr;
+ /*
+ * As defined in MS-NTLM 3.3.2, just this av pair field
+ * is sufficient as part of the temp
+ */
attrptr->type = cpu_to_le16(NTLMSSP_AV_NB_DOMAIN_NAME);
attrptr->length = cpu_to_le16(2 * dlen);
blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
cifs_strtoUCS((__le16 *)blobptr, ses->domainName, dlen, nls_cp);
- blobptr += 2 * dlen;
- attrptr = (struct ntlmssp2_name *) blobptr;
-
- attrptr->type = cpu_to_le16(NTLMSSP_AV_NB_COMPUTER_NAME);
- attrptr->length = cpu_to_le16(2 * wlen);
- blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
- cifs_strtoUCS((__le16 *)blobptr, ses->server->hostname, wlen, nls_cp);
-
- blobptr += 2 * wlen;
- attrptr = (struct ntlmssp2_name *) blobptr;
-
- attrptr->type = cpu_to_le16(NTLMSSP_AV_DNS_DOMAIN_NAME);
- attrptr->length = cpu_to_le16(2 * dlen);
- blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
- cifs_strtoUCS((__le16 *)blobptr, ses->domainName, dlen, nls_cp);
-
- blobptr += 2 * dlen;
- attrptr = (struct ntlmssp2_name *) blobptr;
-
- attrptr->type = cpu_to_le16(NTLMSSP_AV_DNS_COMPUTER_NAME);
- attrptr->length = cpu_to_le16(2 * wlen);
- blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
- cifs_strtoUCS((__le16 *)blobptr, ses->server->hostname, wlen, nls_cp);
-
- blobptr += 2 * wlen;
- attrptr = (struct ntlmssp2_name *) blobptr;
-
- attrptr->type = cpu_to_le16(NTLMSSP_AV_TIMESTAMP);
- attrptr->length = cpu_to_le16(sizeof(__le64));
- blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
- curtime = cpu_to_le64(cifs_UnixTimeToNT(CURRENT_TIME));
- memcpy(blobptr, &curtime, sizeof(__le64));
-
return 0;
}