cifs: Cleanup and thus reduce smb session structure and fields used during authentication
Removed following fields from smb session structure
cryptkey, ntlmv2_hash, tilen, tiblob
and ntlmssp_auth structure is allocated dynamically only if the auth mech
in NTLMSSP.
response field within a session_key structure is used to initially store the
target info (either plucked from type 2 challenge packet in case of NTLMSSP
or fabricated in case of NTLMv2 without extended security) and then to store
Message Authentication Key (mak) (session key + client response).
Server challenge or cryptkey needed during a NTLMSSP authentication
is now part of ntlmssp_auth structure which gets allocated and freed
once authenticaiton process is done.
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 ef95a27..f856732 100644
--- a/fs/cifs/cifsencrypt.c
+++ b/fs/cifs/cifsencrypt.c
@@ -328,15 +328,15 @@
* two times the unicode length of a server name +
* size of a timestamp (which is 8 bytes).
*/
- ses->tilen = size + 2 * (2 * dlen) + 2 * (2 * wlen) + 8;
- ses->tiblob = kzalloc(ses->tilen, GFP_KERNEL);
- if (!ses->tiblob) {
- ses->tilen = 0;
+ ses->auth_key.len = size + 2 * (2 * dlen) + 2 * (2 * wlen) + 8;
+ ses->auth_key.response = kzalloc(ses->auth_key.len, GFP_KERNEL);
+ if (!ses->auth_key.response) {
+ ses->auth_key.len = 0;
cERROR(1, "Challenge target info allocation failure");
return -ENOMEM;
}
- blobptr = ses->tiblob;
+ blobptr = ses->auth_key.response;
attrptr = (struct ntlmssp2_name *) blobptr;
attrptr->type = cpu_to_le16(NTLMSSP_AV_NB_DOMAIN_NAME);
@@ -400,11 +400,11 @@
unsigned char *blobend;
struct ntlmssp2_name *attrptr;
- if (!ses->tilen || !ses->tiblob)
+ if (!ses->auth_key.len || !ses->auth_key.response)
return 0;
- blobptr = ses->tiblob;
- blobend = ses->tiblob + ses->tilen;
+ blobptr = ses->auth_key.response;
+ blobend = blobptr + ses->auth_key.len;
while (blobptr + onesize < blobend) {
attrptr = (struct ntlmssp2_name *) blobptr;
@@ -436,7 +436,7 @@
return 0;
}
-static int calc_ntlmv2_hash(struct cifsSesInfo *ses,
+static int calc_ntlmv2_hash(struct cifsSesInfo *ses, char *ntlmv2_hash,
const struct nls_table *nls_cp)
{
int rc = 0;
@@ -509,7 +509,7 @@
}
rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
- ses->ntlmv2_hash);
+ ntlmv2_hash);
calc_exit_1:
kfree(user);
@@ -518,7 +518,7 @@
}
static int
-CalcNTLMv2_response(const struct cifsSesInfo *ses)
+CalcNTLMv2_response(const struct cifsSesInfo *ses, char *ntlmv2_hash)
{
int rc;
unsigned int offset = CIFS_SESS_KEY_SIZE + 8;
@@ -529,7 +529,7 @@
}
crypto_shash_setkey(ses->server->secmech.hmacmd5,
- ses->ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
+ ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
if (rc) {
@@ -539,7 +539,7 @@
if (ses->server->secType == RawNTLMSSP)
memcpy(ses->auth_key.response + offset,
- ses->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
+ ses->ntlmssp->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
else
memcpy(ses->auth_key.response + offset,
ses->server->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
@@ -558,7 +558,10 @@
{
int rc;
int baselen;
+ unsigned int tilen;
struct ntlmv2_resp *buf;
+ char ntlmv2_hash[16];
+ unsigned char *tiblob = NULL; /* target info blob */
if (ses->server->secType == RawNTLMSSP) {
if (!ses->domainName) {
@@ -572,18 +575,22 @@
rc = build_avpair_blob(ses, nls_cp);
if (rc) {
cERROR(1, "error %d building av pair blob", rc);
- return rc;
+ goto setup_ntlmv2_rsp_ret;
}
}
baselen = CIFS_SESS_KEY_SIZE + sizeof(struct ntlmv2_resp);
- ses->auth_key.len = baselen + ses->tilen;
- ses->auth_key.response = kmalloc(ses->auth_key.len, GFP_KERNEL);
+ tilen = ses->auth_key.len;
+ tiblob = ses->auth_key.response;
+
+ ses->auth_key.response = kmalloc(baselen + tilen, GFP_KERNEL);
if (!ses->auth_key.response) {
rc = ENOMEM;
+ ses->auth_key.len = 0;
cERROR(1, "%s: Can't allocate auth blob", __func__);
goto setup_ntlmv2_rsp_ret;
}
+ ses->auth_key.len += baselen;
buf = (struct ntlmv2_resp *)
(ses->auth_key.response + CIFS_SESS_KEY_SIZE);
@@ -593,17 +600,17 @@
get_random_bytes(&buf->client_chal, sizeof(buf->client_chal));
buf->reserved2 = 0;
- memcpy(ses->auth_key.response + baselen, ses->tiblob, ses->tilen);
+ memcpy(ses->auth_key.response + baselen, tiblob, tilen);
/* calculate ntlmv2_hash */
- rc = calc_ntlmv2_hash(ses, nls_cp);
+ rc = calc_ntlmv2_hash(ses, ntlmv2_hash, nls_cp);
if (rc) {
cERROR(1, "could not get v2 hash rc %d", rc);
goto setup_ntlmv2_rsp_ret;
}
/* calculate first part of the client response (CR1) */
- rc = CalcNTLMv2_response(ses);
+ rc = CalcNTLMv2_response(ses, ntlmv2_hash);
if (rc) {
cERROR(1, "Could not calculate CR1 rc: %d", rc);
goto setup_ntlmv2_rsp_ret;
@@ -611,7 +618,7 @@
/* now calculate the session key for NTLMv2 */
crypto_shash_setkey(ses->server->secmech.hmacmd5,
- ses->ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
+ ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
if (rc) {
@@ -627,9 +634,7 @@
ses->auth_key.response);
setup_ntlmv2_rsp_ret:
- kfree(ses->tiblob);
- ses->tiblob = NULL;
- ses->tilen = 0;
+ kfree(tiblob);
return rc;
}
@@ -657,7 +662,7 @@
CIFS_SESS_KEY_SIZE);
sg_init_one(&sgin, sec_key, CIFS_SESS_KEY_SIZE);
- sg_init_one(&sgout, ses->ntlmssp.ciphertext, CIFS_CPHTXT_SIZE);
+ sg_init_one(&sgout, ses->ntlmssp->ciphertext, CIFS_CPHTXT_SIZE);
rc = crypto_blkcipher_encrypt(&desc, &sgout, &sgin, CIFS_CPHTXT_SIZE);
if (rc) {