On Tue, Sep 7, 2010 at 7:51 AM, Jeff Layton <jlayton@xxxxxxxxx> wrote:
> On Mon, 6 Sep 2010 22:36:24 -0500
> shirishpargaonkar@xxxxxxxxx wrote:
>
>> 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.
>>
>> Use hmac-md5 to genereate ntlmv2 hash, ntlmv2 response, and HMAC (CR1 of
>> ntlmv2 auth blob.
>>
>> Use md5 to generate signature (during send of a request and to verify response)
>>
>>
>> From 90c4637c66ce7ff7901b71526a9844cb658247f5 Mon Sep 17 00:00:00 2001
>> From: Shirish Pargaonkar <shirishpargaonkar@xxxxxxxxx>
>> Date: Mon, 6 Sep 2010 21:56:40 -0500
>> Subject: [PATCH] use kernel crpto apis instead of cifs crypto functions
>>
>> Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@xxxxxxxxx>
>> ---
>> fs/cifs/Kconfig | 3 +
>> fs/cifs/cifsencrypt.c | 248 +++++++++++++++++++++++++++++++++++--------------
>> fs/cifs/cifsproto.h | 5 +-
>> fs/cifs/transport.c | 6 +-
>> 4 files changed, 184 insertions(+), 78 deletions(-)
>>
>> diff --git a/fs/cifs/Kconfig b/fs/cifs/Kconfig
>> index 917b7d4..0ed2139 100644
>> --- a/fs/cifs/Kconfig
>> +++ b/fs/cifs/Kconfig
>> @@ -2,6 +2,9 @@ config CIFS
>> tristate "CIFS support (advanced network filesystem, SMBFS successor)"
>> depends on INET
>> select NLS
>> + select CRYPTO
>> + select CRYPTO_MD5
>> + select CRYPTO_ARC4
>
> Shouldn't this change go earlier in the set? Without that, this set
> isn't really bisectable, right?
Will make this a change as part of the first set.
>
>> help
>> This is the client VFS module for the Common Internet File System
>> (CIFS) protocol which is the successor to the Server Message Block
>> diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c
>> index 0c1e9f2..bb8ee23 100644
>> --- a/fs/cifs/cifsencrypt.c
>> +++ b/fs/cifs/cifsencrypt.c
>> @@ -43,20 +43,39 @@ extern void SMBencrypt(unsigned char *passwd, const unsigned char *c8,
>> unsigned char *p24);
>>
>> static int cifs_calculate_signature(const struct smb_hdr *cifs_pdu,
>> - const struct session_key *key,
>> - char *signature)
>> + struct TCP_Server_Info *server, char *signature)
>> {
>> - struct MD5Context context;
>> + int rc;
>>
>> - if ((cifs_pdu == NULL) || (signature == NULL) || (key == NULL))
>> + if (cifs_pdu == NULL || server == NULL || signature == NULL)
>> return -EINVAL;
>>
>> - cifs_MD5_init(&context);
>> - cifs_MD5_update(&context, (char *)&key->data, key->len);
>> - cifs_MD5_update(&context, cifs_pdu->Protocol, cifs_pdu->smb_buf_length);
>> + if (!server->ntlmssp.sdescmd5) {
>> + cERROR(1,
>> + "cifs_calculate_signature: can't generate signature\n");
>> + return -1;
>> + }
>>
>> - cifs_MD5_final(signature, &context);
>> - return 0;
>> + rc = crypto_shash_init(&server->ntlmssp.sdescmd5->shash);
>> + if (rc) {
>> + cERROR(1, "cifs_calculate_signature: oould not init md5\n");
>> + return rc;
>> + }
>> +
>> + if (server->secType == RawNTLMSSP)
>> + crypto_shash_update(&server->ntlmssp.sdescmd5->shash,
>> + server->ntlmssp.sec_key, CIFS_NTLMV2_SESSKEY_SIZE);
>> + else
>> + crypto_shash_update(&server->ntlmssp.sdescmd5->shash,
>> + (char *)&server->session_key.data,
>> + server->session_key.len);
>> +
>
> Very confusing. If the secType != RawNTLMSSP (e.g. Kerberos), you still
> have to dereference the ntlmssp field in the server struct here. Not
> exactly self documenting, no? Maybe that field should be renamed to
> something generic, or some comments should be added to make it clear
> that it's not *just* for NTLMSSP.
Agree, I can change the name to something pertinent to all security mechanisms
and add comments to clarify.
>
>> + crypto_shash_update(&server->ntlmssp.sdescmd5->shash,
>> + cifs_pdu->Protocol, cifs_pdu->smb_buf_length);
>> +
>> + rc = crypto_shash_final(&server->ntlmssp.sdescmd5->shash, signature);
>> +
>> + return rc;
>> }
>>
>> int cifs_sign_smb(struct smb_hdr *cifs_pdu, struct TCP_Server_Info *server,
>> @@ -80,8 +99,7 @@ int cifs_sign_smb(struct smb_hdr *cifs_pdu, struct TCP_Server_Info *server,
>> server->sequence_number++;
>> spin_unlock(&GlobalMid_Lock);
>>
>> - rc = cifs_calculate_signature(cifs_pdu, &server->session_key,
>> - smb_signature);
>> + rc = cifs_calculate_signature(cifs_pdu, server, smb_signature);
>> if (rc)
>> memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
>> else
>> @@ -91,21 +109,38 @@ int cifs_sign_smb(struct smb_hdr *cifs_pdu, struct TCP_Server_Info *server,
>> }
>>
>> static int cifs_calc_signature2(const struct kvec *iov, int n_vec,
>> - const struct session_key *key, char *signature)
>> + struct TCP_Server_Info *server, char *signature)
>> {
>> - struct MD5Context context;
>> int i;
>> + int rc;
>>
>> - if ((iov == NULL) || (signature == NULL) || (key == NULL))
>> + if (iov == NULL || server == NULL || signature == NULL)
>> return -EINVAL;
>>
>> - cifs_MD5_init(&context);
>> - cifs_MD5_update(&context, (char *)&key->data, key->len);
>> + if (!server->ntlmssp.sdescmd5) {
>> + cERROR(1, "cifs_calc_signature2: can't generate signature\n");
>> + return -1;
>> + }
>> +
>> + rc = crypto_shash_init(&server->ntlmssp.sdescmd5->shash);
>> + if (rc) {
>> + cERROR(1, "cifs_calc_signature2: oould not init md5\n");
>> + return rc;
>> + }
>> +
>> + if (server->secType == RawNTLMSSP)
>> + crypto_shash_update(&server->ntlmssp.sdescmd5->shash,
>> + server->ntlmssp.sec_key, CIFS_NTLMV2_SESSKEY_SIZE);
>> + else
>> + crypto_shash_update(&server->ntlmssp.sdescmd5->shash,
>> + (char *)&server->session_key.data,
>> + server->session_key.len);
>> +
>> for (i = 0; i < n_vec; i++) {
>> if (iov[i].iov_len == 0)
>> continue;
>> if (iov[i].iov_base == NULL) {
>> - cERROR(1, "null iovec entry");
>> + cERROR(1, "cifs_calc_signature2: null iovec entry");
>> return -EIO;
>> }
>> /* The first entry includes a length field (which does not get
>> @@ -113,18 +148,18 @@ static int cifs_calc_signature2(const struct kvec *iov, int n_vec,
>> if (i == 0) {
>> if (iov[0].iov_len <= 8) /* cmd field at offset 9 */
>> break; /* nothing to sign or corrupt header */
>> - cifs_MD5_update(&context, iov[0].iov_base+4,
>> - iov[0].iov_len-4);
>> + crypto_shash_update(&server->ntlmssp.sdescmd5->shash,
>> + iov[i].iov_base + 4, iov[i].iov_len - 4);
>> } else
>> - cifs_MD5_update(&context, iov[i].iov_base, iov[i].iov_len);
>> + crypto_shash_update(&server->ntlmssp.sdescmd5->shash,
>> + iov[i].iov_base, iov[i].iov_len);
>> }
>>
>> - cifs_MD5_final(signature, &context);
>> + rc = crypto_shash_final(&server->ntlmssp.sdescmd5->shash, signature);
>>
>> - return 0;
>> + return rc;
>> }
>>
>> -
>> int cifs_sign_smb2(struct kvec *iov, int n_vec, struct TCP_Server_Info *server,
>> __u32 *pexpected_response_sequence_number)
>> {
>> @@ -147,8 +182,7 @@ int cifs_sign_smb2(struct kvec *iov, int n_vec, struct TCP_Server_Info *server,
>> server->sequence_number++;
>> spin_unlock(&GlobalMid_Lock);
>>
>> - rc = cifs_calc_signature2(iov, n_vec, &server->session_key,
>> - smb_signature);
>> + rc = cifs_calc_signature2(iov, n_vec, server, smb_signature);
>> if (rc)
>> memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
>> else
>> @@ -158,14 +192,14 @@ int cifs_sign_smb2(struct kvec *iov, int n_vec, struct TCP_Server_Info *server,
>> }
>>
>> int cifs_verify_signature(struct smb_hdr *cifs_pdu,
>> - const struct session_key *session_key,
>> + struct TCP_Server_Info *server,
>> __u32 expected_sequence_number)
>> {
>> - unsigned int rc;
>> + int rc;
>> char server_response_sig[8];
>> char what_we_think_sig_should_be[20];
>>
>> - if ((cifs_pdu == NULL) || (session_key == NULL))
>> + if (cifs_pdu == NULL || server == NULL)
>> return -EINVAL;
>>
>> if (cifs_pdu->Command == SMB_COM_NEGOTIATE)
>> @@ -194,7 +228,7 @@ int cifs_verify_signature(struct smb_hdr *cifs_pdu,
>> cpu_to_le32(expected_sequence_number);
>> cifs_pdu->Signature.Sequence.Reserved = 0;
>>
>> - rc = cifs_calculate_signature(cifs_pdu, session_key,
>> + rc = cifs_calculate_signature(cifs_pdu, server,
>> what_we_think_sig_should_be);
>>
>> if (rc)
>> @@ -320,37 +354,51 @@ static int calc_ntlmv2_hash(struct cifsSesInfo *ses,
>> int rc = 0;
>> int len;
>> char nt_hash[CIFS_NTHASH_SIZE];
>> - struct HMACMD5Context *pctxt;
>> wchar_t *user;
>> wchar_t *domain;
>> + wchar_t *server;
>>
>> - pctxt = kmalloc(sizeof(struct HMACMD5Context), GFP_KERNEL);
>> -
>> - if (pctxt == NULL)
>> - return -ENOMEM;
>> + if (!ses->server->ntlmssp.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->ntlmssp.hmacmd5, nt_hash,
>> + CIFS_NTHASH_SIZE);
>> +
>> + rc = crypto_shash_init(&ses->server->ntlmssp.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->ntlmssp.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
>> @@ -358,18 +406,77 @@ 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->ntlmssp.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->ntlmssp.sdeschmacmd5->shash,
>> + (char *)server, 2 * len);
>> +
>> + kfree(server);
>> }
>> +
>> + rc = crypto_shash_final(&ses->server->ntlmssp.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 TCP_Server_Info *server,
>> + char *v2_session_response)
>> +{
>> + int rc;
>> +
>> + if (!server->ntlmssp.sdeschmacmd5) {
>> + cERROR(1, "calc_ntlmv2_hash: can't generate ntlmv2 hash\n");
>> + return -1;
>> + }
>> +
>> + crypto_shash_setkey(server->ntlmssp.hmacmd5, server->ntlmv2_hash,
>> + CIFS_HMAC_MD5_HASH_SIZE);
>> +
>> + rc = crypto_shash_init(&server->ntlmssp.sdeschmacmd5->shash);
>> + if (rc) {
>> + cERROR(1, "CalcNTLMv2_response: could not init hmacmd5");
>> + return rc;
>> + }
>> +
>> + memcpy(v2_session_response + CIFS_SERVER_CHALLENGE_SIZE,
>> + server->cryptKey, CIFS_SERVER_CHALLENGE_SIZE);
>> + crypto_shash_update(&server->ntlmssp.sdeschmacmd5->shash,
>> + v2_session_response + CIFS_SERVER_CHALLENGE_SIZE,
>> + sizeof(struct ntlmv2_resp) - CIFS_SERVER_CHALLENGE_SIZE);
>> +
>> + if (server->tilen)
>> + crypto_shash_update(&server->ntlmssp.sdeschmacmd5->shash,
>> + server->tiblob, server->tilen);
>> +
>> + rc = crypto_shash_final(&server->ntlmssp.sdeschmacmd5->shash,
>> + v2_session_response);
>> +
>> return rc;
>> }
>>
>> @@ -379,7 +486,6 @@ setup_ntlmv2_rsp(struct cifsSesInfo *ses, char *resp_buf,
>> {
>> int rc = 0;
>> struct ntlmv2_resp *buf = (struct ntlmv2_resp *)resp_buf;
>> - struct HMACMD5Context context;
>>
>> buf->blob_signature = cpu_to_le32(0x00000101);
>> buf->reserved = 0;
>> @@ -397,44 +503,44 @@ setup_ntlmv2_rsp(struct cifsSesInfo *ses, char *resp_buf,
>>
>> /* calculate buf->ntlmv2_hash */
>> rc = calc_ntlmv2_hash(ses, nls_cp);
>> - if (rc)
>> + if (rc) {
>> + cERROR(1, "could not get v2 hash rc %d", rc);
>> + return rc;
>> + }
>> + rc = CalcNTLMv2_response(ses->server, resp_buf);
>> + if (rc) {
>> cERROR(1, "could not get v2 hash rc %d", rc);
>> - CalcNTLMv2_response(ses, resp_buf);
>> + return rc;
>> + }
>>
>> - /* 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);
>> + if (!ses->server->ntlmssp.sdeschmacmd5) {
>> + cERROR(1, "calc_ntlmv2_hash: can't generate ntlmv2 hash\n");
>> + return -1;
>> + }
>>
>> - memcpy(&ses->server->session_key.data.ntlmv2.resp, resp_buf,
>> - sizeof(struct ntlmv2_resp));
>> - ses->server->session_key.len = 16 + sizeof(struct ntlmv2_resp);
>> + crypto_shash_setkey(ses->server->ntlmssp.hmacmd5,
>> + ses->server->ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
>>
>> - return rc;
>> -}
>> + rc = crypto_shash_init(&ses->server->ntlmssp.sdeschmacmd5->shash);
>> + if (rc) {
>> + cERROR(1, "setup_ntlmv2_rsp: could not init hmacmd5\n");
>> + 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 + CIFS_SERVER_CHALLENGE_SIZE,
>> - ses->server->cryptKey, CIFS_SERVER_CHALLENGE_SIZE);
>> - hmac_md5_init_limK_to_64(ses->server->ntlmv2_hash,
>> - CIFS_HMAC_MD5_HASH_SIZE, &context);
>> + crypto_shash_update(&ses->server->ntlmssp.sdeschmacmd5->shash,
>> + resp_buf, CIFS_HMAC_MD5_HASH_SIZE);
>>
>> - hmac_md5_update(v2_session_response + CIFS_SERVER_CHALLENGE_SIZE,
>> - sizeof(struct ntlmv2_resp) - CIFS_SERVER_CHALLENGE_SIZE,
>> - &context);
>> + rc = crypto_shash_final(&ses->server->ntlmssp.sdeschmacmd5->shash,
>> + ses->server->session_key.data.ntlmv2.key);
>>
>> - if (ses->server->tilen)
>> - hmac_md5_update(ses->server->tiblob,
>> - ses->server->tilen, &context);
>> + memcpy(&ses->server->session_key.data.ntlmv2.resp, resp_buf,
>> + sizeof(struct ntlmv2_resp));
>> + ses->server->session_key.len = 16 + sizeof(struct ntlmv2_resp);
>>
>> - hmac_md5_final(v2_session_response, &context);
>> -/* cifs_dump_mem("v2_sess_rsp: ", v2_session_response, 32); */
>> + return rc;
>> }
>>
>> +
>> int
>> calc_seckey(struct TCP_Server_Info *server)
>> {
>> diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
>> index 7c115a8..1378d91 100644
>> --- a/fs/cifs/cifsproto.h
>> +++ b/fs/cifs/cifsproto.h
>> @@ -361,13 +361,10 @@ extern int cifs_sign_smb(struct smb_hdr *, struct TCP_Server_Info *, __u32 *);
>> extern int cifs_sign_smb2(struct kvec *iov, int n_vec, struct TCP_Server_Info *,
>> __u32 *);
>> extern int cifs_verify_signature(struct smb_hdr *,
>> - const struct session_key *session_key,
>> + struct TCP_Server_Info *server,
>> __u32 expected_sequence_number);
>> extern int cifs_calculate_session_key(struct session_key *key, const char *rn,
>> const char *pass);
>> -extern int CalcNTLMv2_partial_mac_key(struct cifsSesInfo *,
>> - const struct nls_table *);
>> -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 *);
>> diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c
>> index a66c91e..e0588cd 100644
>> --- a/fs/cifs/transport.c
>> +++ b/fs/cifs/transport.c
>> @@ -543,7 +543,7 @@ SendReceive2(const unsigned int xid, struct cifsSesInfo *ses,
>> (ses->server->secMode & (SECMODE_SIGN_REQUIRED |
>> SECMODE_SIGN_ENABLED))) {
>> rc = cifs_verify_signature(midQ->resp_buf,
>> - &ses->server->session_key,
>> + ses->server,
>> midQ->sequence_number+1);
>> if (rc) {
>> cERROR(1, "Unexpected SMB signature");
>> @@ -731,7 +731,7 @@ SendReceive(const unsigned int xid, struct cifsSesInfo *ses,
>> (ses->server->secMode & (SECMODE_SIGN_REQUIRED |
>> SECMODE_SIGN_ENABLED))) {
>> rc = cifs_verify_signature(out_buf,
>> - &ses->server->session_key,
>> + ses->server,
>> midQ->sequence_number+1);
>> if (rc) {
>> cERROR(1, "Unexpected SMB signature");
>> @@ -981,7 +981,7 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifsTconInfo *tcon,
>> (ses->server->secMode & (SECMODE_SIGN_REQUIRED |
>> SECMODE_SIGN_ENABLED))) {
>> rc = cifs_verify_signature(out_buf,
>> - &ses->server->session_key,
>> + ses->server,
>> midQ->sequence_number+1);
>> if (rc) {
>> cERROR(1, "Unexpected SMB signature");
>
>
> --
> Jeff Layton <jlayton@xxxxxxxxx>
>
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