On Tue, Sep 7, 2010 at 7:35 AM, Jeff Layton <jlayton@xxxxxxxxx> wrote:
> On Mon, 6 Sep 2010 22:35:23 -0500
> shirishpargaonkar@xxxxxxxxx wrote:
>
>> From: Shirish Pargaonkar <shirishpargaonkar@xxxxxxxxx>
>>
>> Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@xxxxxxxxx>
>> ---
>> fs/cifs/cifsencrypt.c | 33 ++++++++++++--------
>> fs/cifs/cifsglob.h | 2 +-
>> fs/cifs/cifsproto.h | 2 +-
>> fs/cifs/sess.c | 80 +++++++++++++++++++++++++++++++++---------------
>> fs/cifs/transport.c | 6 ++--
>> 5 files changed, 80 insertions(+), 43 deletions(-)
>>
>> diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c
>> index 5f0fc6b..5fbd19b 100644
>> --- a/fs/cifs/cifsencrypt.c
>> +++ b/fs/cifs/cifsencrypt.c
>> @@ -80,7 +80,7 @@ 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->mac_signing_key,
>> + rc = cifs_calculate_signature(cifs_pdu, &server->session_key,
>> smb_signature);
>> if (rc)
>> memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
>> @@ -147,7 +147,7 @@ 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->mac_signing_key,
>> + rc = cifs_calc_signature2(iov, n_vec, &server->session_key,
>> smb_signature);
>> if (rc)
>> memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
>> @@ -211,7 +211,7 @@ int cifs_verify_signature(struct smb_hdr *cifs_pdu,
>> }
>>
>> /* We fill in key by putting in 40 byte array which was allocated by caller */
>> -int cifs_calculate_mac_key(struct session_key *key, const char *rn,
>> +int cifs_calculate_session_key(struct session_key *key, const char *rn,
>> const char *password)
>> {
>> char temp_key[16];
>> @@ -319,7 +319,7 @@ static int calc_ntlmv2_hash(struct cifsSesInfo *ses,
>> {
>> int rc = 0;
>> int len;
>> - char nt_hash[16];
>> + char nt_hash[CIFS_NTHASH_SIZE];
>> struct HMACMD5Context *pctxt;
>> wchar_t *user;
>> wchar_t *domain;
>> @@ -377,7 +377,7 @@ int
>> setup_ntlmv2_rsp(struct cifsSesInfo *ses, char *resp_buf,
>> const struct nls_table *nls_cp)
>> {
>> - int rc;
>> + int rc = 0;
>> struct ntlmv2_resp *buf = (struct ntlmv2_resp *)resp_buf;
>> struct HMACMD5Context context;
>>
>> @@ -404,11 +404,11 @@ setup_ntlmv2_rsp(struct cifsSesInfo *ses, char *resp_buf,
>> /* 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->mac_signing_key.data.ntlmv2.key, &context);
>> + hmac_md5_final(ses->server->session_key.data.ntlmv2.key, &context);
>>
>> - memcpy(&ses->server->mac_signing_key.data.ntlmv2.resp, resp_buf,
>> + memcpy(&ses->server->session_key.data.ntlmv2.resp, resp_buf,
>> sizeof(struct ntlmv2_resp));
>> - ses->server->mac_signing_key.len = 16 + sizeof(struct ntlmv2_resp);
>> + ses->server->session_key.len = 16 + sizeof(struct ntlmv2_resp);
>>
>> return rc;
>> }
>> @@ -418,11 +418,18 @@ void CalcNTLMv2_response(const struct cifsSesInfo *ses,
>> {
>> 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);
>> + 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);
>> +
>> + hmac_md5_update(v2_session_response + CIFS_SERVER_CHALLENGE_SIZE,
>> + sizeof(struct ntlmv2_resp) - CIFS_SERVER_CHALLENGE_SIZE,
>> + &context);
>> +
>> + if (ses->server->tilen)
>> + hmac_md5_update(ses->server->tiblob,
>> + ses->server->tilen, &context);
>>
>> hmac_md5_final(v2_session_response, &context);
>> /* cifs_dump_mem("v2_sess_rsp: ", v2_session_response, 32); */
>> diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
>> index 6b7249e..f67a5d7 100644
>> --- a/fs/cifs/cifsglob.h
>> +++ b/fs/cifs/cifsglob.h
>> @@ -201,7 +201,7 @@ struct TCP_Server_Info {
>> /* 16th byte of RFC1001 workstation name is always null */
>> char workstation_RFC1001_name[RFC1001_NAME_LEN_WITH_NULL];
>> __u32 sequence_number; /* needed for CIFS PDU signature */
>> - struct session_key mac_signing_key;
>> + struct session_key session_key;
>> char ntlmv2_hash[16];
>> unsigned long lstrp; /* when we got last response from this server */
>> u16 dialect; /* dialect index that server chose */
>> diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
>> index ccc6d57..d1b9bc4 100644
>> --- a/fs/cifs/cifsproto.h
>> +++ b/fs/cifs/cifsproto.h
>> @@ -363,7 +363,7 @@ extern int cifs_sign_smb2(struct kvec *iov, int n_vec, struct TCP_Server_Info *,
>> extern int cifs_verify_signature(struct smb_hdr *,
>> const struct session_key *session_key,
>> __u32 expected_sequence_number);
>> -extern int cifs_calculate_mac_key(struct session_key *key, const char *rn,
>> +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 *);
>> diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
>> index 6551b17..f7fc3dc 100644
>> --- a/fs/cifs/sess.c
>> +++ b/fs/cifs/sess.c
>> @@ -442,7 +442,7 @@ static void build_ntlmssp_negotiate_blob(unsigned char *pbuffer,
>> /* BB is NTLMV2 session security format easier to use here? */
>> flags = NTLMSSP_NEGOTIATE_56 | NTLMSSP_REQUEST_TARGET |
>> NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
>> - NTLMSSP_NEGOTIATE_NT_ONLY | NTLMSSP_NEGOTIATE_NTLM;
>> + NTLMSSP_NEGOTIATE_NTLM;
>> if (ses->server->secMode &
>> (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
>> flags |= NTLMSSP_NEGOTIATE_SIGN;
>> @@ -468,10 +468,12 @@ static int build_ntlmssp_auth_blob(unsigned char *pbuffer,
>> struct cifsSesInfo *ses,
>> const struct nls_table *nls_cp, bool first)
>> {
>> + int rc;
>> + unsigned int size;
>> AUTHENTICATE_MESSAGE *sec_blob = (AUTHENTICATE_MESSAGE *)pbuffer;
>> __u32 flags;
>> unsigned char *tmp;
>> - char ntlm_session_key[CIFS_SESS_KEY_SIZE];
>> + struct ntlmv2_resp ntlmv2_response = {};
>>
>> memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
>> sec_blob->MessageType = NtLmAuthenticate;
>> @@ -479,7 +481,7 @@ static int build_ntlmssp_auth_blob(unsigned char *pbuffer,
>> flags = NTLMSSP_NEGOTIATE_56 |
>> NTLMSSP_REQUEST_TARGET | NTLMSSP_NEGOTIATE_TARGET_INFO |
>> NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
>> - NTLMSSP_NEGOTIATE_NT_ONLY | NTLMSSP_NEGOTIATE_NTLM;
>> + NTLMSSP_NEGOTIATE_NTLM;
>> if (ses->server->secMode &
>> (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
>> flags |= NTLMSSP_NEGOTIATE_SIGN;
>> @@ -494,19 +496,25 @@ static int build_ntlmssp_auth_blob(unsigned char *pbuffer,
>> sec_blob->LmChallengeResponse.Length = 0;
>> sec_blob->LmChallengeResponse.MaximumLength = 0;
>>
>> - /* calculate session key, BB what about adding similar ntlmv2 path? */
>> - SMBNTencrypt(ses->password, ses->server->cryptKey, ntlm_session_key);
>> - if (first)
>> - cifs_calculate_mac_key(&ses->server->mac_signing_key,
>> - ntlm_session_key, ses->password);
>> -
>> - memcpy(tmp, ntlm_session_key, CIFS_SESS_KEY_SIZE);
>> sec_blob->NtChallengeResponse.BufferOffset = cpu_to_le32(tmp - pbuffer);
>> - sec_blob->NtChallengeResponse.Length = cpu_to_le16(CIFS_SESS_KEY_SIZE);
>> - sec_blob->NtChallengeResponse.MaximumLength =
>> - cpu_to_le16(CIFS_SESS_KEY_SIZE);
>> + rc = setup_ntlmv2_rsp(ses, (char *)&ntlmv2_response, nls_cp);
>> + if (rc) {
>> + cERROR(1, "error rc: %d during ntlmssp ntlmv2 setup", rc);
>> + goto setup_ntlmv2_ret;
>> + }
>> + size = sizeof(struct ntlmv2_resp);
>> + memcpy(tmp, (char *)&ntlmv2_response, size);
>> + tmp += size;
>> + if (ses->server->tilen > 0) {
>> + memcpy(tmp, ses->server->tiblob, ses->server->tilen);
>> + tmp += ses->server->tilen;
>> + } else
>> + ses->server->tilen = 0;
>>
>> - tmp += CIFS_SESS_KEY_SIZE;
>> + sec_blob->NtChallengeResponse.Length = cpu_to_le16(size +
>> + ses->server->tilen);
>> + sec_blob->NtChallengeResponse.MaximumLength =
>> + cpu_to_le16(size + ses->server->tilen);
>>
>> if (ses->domainName == NULL) {
>> sec_blob->DomainName.BufferOffset = cpu_to_le32(tmp - pbuffer);
>> @@ -518,7 +526,6 @@ static int build_ntlmssp_auth_blob(unsigned char *pbuffer,
>> len = cifs_strtoUCS((__le16 *)tmp, ses->domainName,
>> MAX_USERNAME_SIZE, nls_cp);
>> len *= 2; /* unicode is 2 bytes each */
>> - len += 2; /* trailing null */
>> sec_blob->DomainName.BufferOffset = cpu_to_le32(tmp - pbuffer);
>> sec_blob->DomainName.Length = cpu_to_le16(len);
>> sec_blob->DomainName.MaximumLength = cpu_to_le16(len);
>> @@ -535,7 +542,6 @@ static int build_ntlmssp_auth_blob(unsigned char *pbuffer,
>> len = cifs_strtoUCS((__le16 *)tmp, ses->userName,
>> MAX_USERNAME_SIZE, nls_cp);
>> len *= 2; /* unicode is 2 bytes each */
>> - len += 2; /* trailing null */
>> sec_blob->UserName.BufferOffset = cpu_to_le32(tmp - pbuffer);
>> sec_blob->UserName.Length = cpu_to_le16(len);
>> sec_blob->UserName.MaximumLength = cpu_to_le16(len);
>> @@ -551,6 +557,7 @@ static int build_ntlmssp_auth_blob(unsigned char *pbuffer,
>> sec_blob->SessionKey.Length = 0;
>> sec_blob->SessionKey.MaximumLength = 0;
>>
>> +setup_ntlmv2_ret:
>> if (ses->server->tilen > 0)
>> kfree(ses->server->tiblob);
>>
>> @@ -567,15 +574,14 @@ static void setup_ntlmssp_neg_req(SESSION_SETUP_ANDX *pSMB,
>> return;
>> }
>>
>> -static int setup_ntlmssp_auth_req(SESSION_SETUP_ANDX *pSMB,
>> +static int setup_ntlmssp_auth_req(char *ntlmsspblob,
>> struct cifsSesInfo *ses,
>> const struct nls_table *nls, bool first_time)
>> {
>> int bloblen;
>>
>> - bloblen = build_ntlmssp_auth_blob(&pSMB->req.SecurityBlob[0], ses, nls,
>> + bloblen = build_ntlmssp_auth_blob(ntlmsspblob, ses, nls,
>> first_time);
>> - pSMB->req.SecurityBlobLength = cpu_to_le16(bloblen);
>>
>> return bloblen;
>> }
>> @@ -711,7 +717,7 @@ ssetup_ntlmssp_authenticate:
>>
>> if (first_time) /* should this be moved into common code
>> with similar ntlmv2 path? */
>> - cifs_calculate_mac_key(&ses->server->mac_signing_key,
>> + cifs_calculate_session_key(&ses->server->session_key,
>> ntlm_session_key, ses->password);
>> /* copy session key */
>>
>> @@ -751,10 +757,19 @@ ssetup_ntlmssp_authenticate:
>>
>> /* calculate session key */
>> rc = setup_ntlmv2_rsp(ses, v2_sess_key, nls_cp);
>> + if (rc) {
>> + kfree(v2_sess_key);
>> + goto ssetup_exit;
>> + }
>> memcpy(bcc_ptr, (char *)v2_sess_key,
>> sizeof(struct ntlmv2_resp));
>> bcc_ptr += sizeof(struct ntlmv2_resp);
>> kfree(v2_sess_key);
>> + if (ses->server->tilen > 0) {
>> + memcpy(bcc_ptr, ses->server->tiblob,
>> + ses->server->tilen);
>> + bcc_ptr += ses->server->tilen;
>> + }
>> if (ses->capabilities & CAP_UNICODE) {
>> if (iov[0].iov_len % 2) {
>> *bcc_ptr = 0;
>> @@ -785,15 +800,15 @@ ssetup_ntlmssp_authenticate:
>> }
>> /* bail out if key is too long */
>> if (msg->sesskey_len >
>> - sizeof(ses->server->mac_signing_key.data.krb5)) {
>> + sizeof(ses->server->session_key.data.krb5)) {
>> cERROR(1, "Kerberos signing key too long (%u bytes)",
>> msg->sesskey_len);
>> rc = -EOVERFLOW;
>> goto ssetup_exit;
>> }
>> if (first_time) {
>> - ses->server->mac_signing_key.len = msg->sesskey_len;
>> - memcpy(ses->server->mac_signing_key.data.krb5,
>> + ses->server->session_key.len = msg->sesskey_len;
>> + memcpy(ses->server->session_key.data.krb5,
>> msg->data, msg->sesskey_len);
>> }
>> pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
>> @@ -835,12 +850,28 @@ ssetup_ntlmssp_authenticate:
>> if (phase == NtLmNegotiate) {
>> setup_ntlmssp_neg_req(pSMB, ses);
>> iov[1].iov_len = sizeof(NEGOTIATE_MESSAGE);
>> + iov[1].iov_base = &pSMB->req.SecurityBlob[0];
>> } else if (phase == NtLmAuthenticate) {
>> int blob_len;
>> - blob_len = setup_ntlmssp_auth_req(pSMB, ses,
>> + char *ntlmsspblob;
>> +
>> + ntlmsspblob = kmalloc(5 *
> ^^^^^^^^^^
> Why 5 here?
>
>> + sizeof(struct _AUTHENTICATE_MESSAGE),
>> + GFP_KERNEL);
>> + if (!ntlmsspblob) {
>> + cERROR(1, "Can't allocate NTLMSSP");
>> + rc = -ENOMEM;
>> + goto ssetup_exit;
>> + }
>> +
>> + blob_len = setup_ntlmssp_auth_req(ntlmsspblob,
>> + ses,
>> nls_cp,
>> first_time);
>> iov[1].iov_len = blob_len;
>> + iov[1].iov_base = ntlmsspblob;
>> + pSMB->req.SecurityBlobLength =
>> + cpu_to_le16(blob_len);
>> /* Make sure that we tell the server that we
>> are using the uid that it just gave us back
>> on the response (challenge) */
>> @@ -850,7 +881,6 @@ ssetup_ntlmssp_authenticate:
>> rc = -ENOSYS;
>> goto ssetup_exit;
>> }
>> - iov[1].iov_base = &pSMB->req.SecurityBlob[0];
>> /* unicode strings must be word aligned */
>> if ((iov[0].iov_len + iov[1].iov_len) % 2) {
>> *bcc_ptr = 0;
>> diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c
>> index 82f78c4..a66c91e 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->mac_signing_key,
>> + &ses->server->session_key,
>> 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->mac_signing_key,
>> + &ses->server->session_key,
>> 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->mac_signing_key,
>> + &ses->server->session_key,
>> midQ->sequence_number+1);
>> if (rc) {
>> cERROR(1, "Unexpected SMB signature");
>
>
> --
> Jeff Layton <jlayton@xxxxxxxxx>
>
An empirical value, that is good enough to hold even if we had all 10 fields
in AV pairs/Target Info. Even if we decide to include LM2 key (for
whatever reason
like passthrough authentication, if at all), that size would be good enough.
--
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