2010-09-09 18:13:30

by Shirish Pargaonkar

[permalink] [raw]
Subject: [PATCH -v2 5/6] convert hash calculations to use crypto apis

From: Shirish Pargaonkar <[email protected]>

Use kernel crypto sync hash apis insetead of cifs crypto functions.
The calls typically corrospond one to one except that insead of
key init, setkey is used.


Signed-off-by: Shirish Pargaonkar <[email protected]>
---
fs/cifs/cifsencrypt.c | 152 ++++++++++++++++++++++++++++++++++++-------------
fs/cifs/cifsproto.h | 1 -
2 files changed, 112 insertions(+), 41 deletions(-)

diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c
index 09d9f74..e72b0e5 100644
--- a/fs/cifs/cifsencrypt.c
+++ b/fs/cifs/cifsencrypt.c
@@ -342,38 +342,52 @@ static int calc_ntlmv2_hash(struct cifsSesInfo *ses,
{
int rc = 0;
int len;
- char nt_hash[16];
- struct HMACMD5Context *pctxt;
+ char nt_hash[CIFS_NTHASH_SIZE];
wchar_t *user;
wchar_t *domain;
+ wchar_t *server;

- pctxt = kmalloc(sizeof(struct HMACMD5Context), GFP_KERNEL);
-
- if (pctxt == NULL)
- return -ENOMEM;
+ if (!ses->server->secmech.sdeschmacmd5) {
+ cERROR(1, "calc_ntlmv2_hash: can't generate ntlmv2 hash\n");
+ return -1;
+ }

/* calculate md4 hash of password */
E_md4hash(ses->password, nt_hash);

- /* convert Domainname to unicode and uppercase */
- hmac_md5_init_limK_to_64(nt_hash, 16, pctxt);
+ crypto_shash_setkey(ses->server->secmech.hmacmd5, nt_hash,
+ CIFS_NTHASH_SIZE);
+
+ rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
+ if (rc) {
+ cERROR(1, "calc_ntlmv2_hash: could not init hmacmd5\n");
+ return rc;
+ }

/* convert ses->userName to unicode and uppercase */
len = strlen(ses->userName);
user = kmalloc(2 + (len * 2), GFP_KERNEL);
- if (user == NULL)
+ if (user == NULL) {
+ cERROR(1, "calc_ntlmv2_hash: user mem alloc failure\n");
+ rc = -ENOMEM;
goto calc_exit_2;
+ }
len = cifs_strtoUCS((__le16 *)user, ses->userName, len, nls_cp);
UniStrupr(user);
- hmac_md5_update((char *)user, 2*len, pctxt);
+
+ crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
+ (char *)user, 2 * len);

/* convert ses->domainName to unicode and uppercase */
if (ses->domainName) {
len = strlen(ses->domainName);

domain = kmalloc(2 + (len * 2), GFP_KERNEL);
- if (domain == NULL)
+ if (domain == NULL) {
+ cERROR(1, "calc_ntlmv2_hash: domain mem alloc failure");
+ rc = -ENOMEM;
goto calc_exit_1;
+ }
len = cifs_strtoUCS((__le16 *)domain, ses->domainName, len,
nls_cp);
/* the following line was removed since it didn't work well
@@ -381,18 +395,76 @@ static int calc_ntlmv2_hash(struct cifsSesInfo *ses,
Maybe converting the domain name earlier makes sense */
/* UniStrupr(domain); */

- hmac_md5_update((char *)domain, 2*len, pctxt);
+ crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
+ (char *)domain, 2 * len);

kfree(domain);
+ } else if (ses->serverName) {
+ len = strlen(ses->serverName);
+
+ server = kmalloc(2 + (len * 2), GFP_KERNEL);
+ if (server == NULL) {
+ cERROR(1, "calc_ntlmv2_hash: server mem alloc failure");
+ rc = -ENOMEM;
+ goto calc_exit_1;
+ }
+ len = cifs_strtoUCS((__le16 *)server, ses->serverName, len,
+ nls_cp);
+ /* the following line was removed since it didn't work well
+ with lower cased domain name that passed as an option.
+ Maybe converting the domain name earlier makes sense */
+ /* UniStrupr(domain); */
+
+ crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
+ (char *)server, 2 * len);
+
+ kfree(server);
}
+
+ rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
+ ses->server->ntlmv2_hash);
+
calc_exit_1:
kfree(user);
calc_exit_2:
/* BB FIXME what about bytes 24 through 40 of the signing key?
compare with the NTLM example */
- hmac_md5_final(ses->server->ntlmv2_hash, pctxt);

- kfree(pctxt);
+ return rc;
+}
+
+static int
+CalcNTLMv2_response(const struct cifsSesInfo *ses, char *v2_session_response)
+{
+ int rc;
+
+ if (!ses->server->secmech.sdeschmacmd5) {
+ cERROR(1, "calc_ntlmv2_hash: can't generate ntlmv2 hash\n");
+ return -1;
+ }
+
+ crypto_shash_setkey(ses->server->secmech.hmacmd5,
+ ses->server->ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
+
+ rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
+ if (rc) {
+ cERROR(1, "CalcNTLMv2_response: could not init hmacmd5");
+ return rc;
+ }
+
+ memcpy(v2_session_response + CIFS_SERVER_CHALLENGE_SIZE,
+ ses->server->cryptKey, CIFS_SERVER_CHALLENGE_SIZE);
+ crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
+ v2_session_response + CIFS_SERVER_CHALLENGE_SIZE,
+ sizeof(struct ntlmv2_resp) - CIFS_SERVER_CHALLENGE_SIZE);
+
+ if (ses->tilen)
+ crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
+ ses->tiblob, ses->tilen);
+
+ rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
+ v2_session_response);
+
return rc;
}

@@ -402,7 +474,6 @@ setup_ntlmv2_rsp(struct cifsSesInfo *ses, char *resp_buf,
{
int rc;
struct ntlmv2_resp *buf = (struct ntlmv2_resp *)resp_buf;
- struct HMACMD5Context context;

buf->blob_signature = cpu_to_le32(0x00000101);
buf->reserved = 0;
@@ -432,15 +503,35 @@ setup_ntlmv2_rsp(struct cifsSesInfo *ses, char *resp_buf,
cERROR(1, "could not get v2 hash rc %d", rc);
goto setup_ntlmv2_rsp_ret;
}
- CalcNTLMv2_response(ses, resp_buf);
+ rc = CalcNTLMv2_response(ses, resp_buf);
+ if (rc) {
+ cERROR(1, "could not get v2 hash rc %d", rc);
+ goto setup_ntlmv2_rsp_ret;
+ }
+
+ if (!ses->server->secmech.sdeschmacmd5) {
+ cERROR(1, "calc_ntlmv2_hash: can't generate ntlmv2 hash\n");
+ rc = -1;
+ goto setup_ntlmv2_rsp_ret;
+ }
+
+ crypto_shash_setkey(ses->server->secmech.hmacmd5,
+ ses->server->ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
+
+ rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
+ if (rc) {
+ cERROR(1, "setup_ntlmv2_rsp: could not init hmacmd5\n");
+ goto setup_ntlmv2_rsp_ret;
+ }
+
+ crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
+ resp_buf, CIFS_HMAC_MD5_HASH_SIZE);

- /* now calculate the MAC key for NTLMv2 */
- hmac_md5_init_limK_to_64(ses->server->ntlmv2_hash, 16, &context);
- hmac_md5_update(resp_buf, 16, &context);
- hmac_md5_final(ses->server->session_key.data.ntlmv2.key, &context);
+ rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
+ ses->server->session_key.data.ntlmv2.key);

memcpy(&ses->server->session_key.data.ntlmv2.resp, resp_buf,
- sizeof(struct ntlmv2_resp));
+ sizeof(struct ntlmv2_resp));
ses->server->session_key.len = 16 + sizeof(struct ntlmv2_resp);

return 0;
@@ -452,25 +543,6 @@ setup_ntlmv2_rsp_ret:
return rc;
}

-void CalcNTLMv2_response(const struct cifsSesInfo *ses,
- char *v2_session_response)
-{
- struct HMACMD5Context context;
- /* rest of v2 struct already generated */
- memcpy(v2_session_response + 8, ses->server->cryptKey, 8);
- hmac_md5_init_limK_to_64(ses->server->ntlmv2_hash, 16, &context);
-
- hmac_md5_update(v2_session_response+8,
- sizeof(struct ntlmv2_resp) - 8, &context);
-
- if (ses->tilen)
- hmac_md5_update(ses->tiblob,
- ses->tilen, &context);
-
- hmac_md5_final(v2_session_response, &context);
-/* cifs_dump_mem("v2_sess_rsp: ", v2_session_response, 32); */
-}
-
int
calc_seckey(struct TCP_Server_Info *server)
{
diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
index d89a87a..8fe46f5 100644
--- a/fs/cifs/cifsproto.h
+++ b/fs/cifs/cifsproto.h
@@ -366,7 +366,6 @@ extern int cifs_verify_signature(struct smb_hdr *,
__u32 expected_sequence_number);
extern int cifs_calculate_session_key(struct session_key *key, const char *rn,
const char *pass);
-extern void CalcNTLMv2_response(const struct cifsSesInfo *, char *);
extern int setup_ntlmv2_rsp(struct cifsSesInfo *, char *,
const struct nls_table *);
extern int cifs_crypto_shash_allocate(struct TCP_Server_Info *);
--
1.6.0.2