On Mon, Oct 4, 2010 at 6:02 AM, Jeff Layton <jlayton@xxxxxxxxxx> wrote:
> On Wed, 29 Sep 2010 09:39:37 -0500
> shirishpargaonkar@xxxxxxxxx wrote:
>
>> From: Shirish Pargaonkar <shirishpargaonkar@xxxxxxxxx>
>>
>>
>> Start calculation auth response within a session. Move/Add pertinet
>> data structures like session key, server challenge and ntlmv2_hash in
>> a session structure. We should do the calculations within a session
>> before copying session key and response over to server data
>> structures because a session setup can fail.
>>
>>
>> Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@xxxxxxxxx>
>> ---
>> fs/cifs/cifsencrypt.c | 16 ++++++++--------
>> fs/cifs/cifsglob.h | 6 ++++--
>> fs/cifs/cifssmb.c | 4 ++--
>> fs/cifs/connect.c | 7 ++++---
>> fs/cifs/sess.c | 17 ++++++++---------
>> 5 files changed, 26 insertions(+), 24 deletions(-)
>>
>> diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c
>> index 7ca9c80..0dda565 100644
>> --- a/fs/cifs/cifsencrypt.c
>> +++ b/fs/cifs/cifsencrypt.c
>> @@ -458,7 +458,7 @@ calc_exit_1:
>> 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);
>> + hmac_md5_final(ses->ntlmv2_hash, pctxt);
>>
>> kfree(pctxt);
>> return rc;
>> @@ -502,14 +502,14 @@ setup_ntlmv2_rsp(struct cifsSesInfo *ses, char *resp_buf,
>> }
>> CalcNTLMv2_response(ses, resp_buf);
>>
>> - /* now calculate the MAC key for NTLMv2 */
>> - hmac_md5_init_limK_to_64(ses->server->ntlmv2_hash, 16, &context);
>> + /* now calculate the session key for NTLMv2 */
>> + hmac_md5_init_limK_to_64(ses->ntlmv2_hash, 16, &context);
>> hmac_md5_update(resp_buf, 16, &context);
>> - hmac_md5_final(ses->server->session_key.data.ntlmv2.key, &context);
>> + hmac_md5_final(ses->auth_key.data.ntlmv2.key, &context);
>>
>> - memcpy(&ses->server->session_key.data.ntlmv2.resp, resp_buf,
>> + memcpy(&ses->auth_key.data.ntlmv2.resp, resp_buf,
>> sizeof(struct ntlmv2_resp));
>> - ses->server->session_key.len = 16 + sizeof(struct ntlmv2_resp);
>> + ses->auth_key.len = 16 + sizeof(struct ntlmv2_resp);
>>
>> return 0;
>>
>> @@ -526,8 +526,8 @@ 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);
>> + memcpy(v2_session_response + 8, ses->cryptKey, 8);
>> + hmac_md5_init_limK_to_64(ses->ntlmv2_hash, 16, &context);
>>
>> hmac_md5_update(v2_session_response+8,
>> sizeof(struct ntlmv2_resp) - 8, &context);
>> diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
>> index c265ebd..4ae331c 100644
>> --- a/fs/cifs/cifsglob.h
>> +++ b/fs/cifs/cifsglob.h
>> @@ -179,12 +179,10 @@ struct TCP_Server_Info {
>> int capabilities; /* allow selective disabling of caps by smb sess */
>> int timeAdj; /* Adjust for difference in server time zone in sec */
>> __u16 CurrentMid; /* multiplex id - rotating counter */
>> - char cryptKey[CIFS_CRYPTO_KEY_SIZE];
>> /* 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 session_key;
>> - char ntlmv2_hash[16];
>> unsigned long lstrp; /* when we got last response from this server */
>> u16 dialect; /* dialect index that server chose */
>> /* extended security flavors that server supports */
>> @@ -192,6 +190,7 @@ struct TCP_Server_Info {
>> bool sec_mskerberos; /* supports legacy MS Kerberos */
>> bool sec_kerberosu2u; /* supports U2U Kerberos */
>> bool sec_ntlmssp; /* supports NTLMSSP */
>> + bool session_estab; /* mark when very first sess is established */
>> #ifdef CONFIG_CIFS_FSCACHE
>> struct fscache_cookie *fscache; /* client index cache cookie */
>> #endif
>> @@ -223,6 +222,9 @@ struct cifsSesInfo {
>> char userName[MAX_USERNAME_SIZE + 1];
>> char *domainName;
>> char *password;
>> + char cryptKey[CIFS_CRYPTO_KEY_SIZE];
>> + struct session_key auth_key;
>> + char ntlmv2_hash[16];
>> unsigned int tilen; /* length of the target info blob */
>> unsigned char *tiblob; /* target info blob in challenge response */
>> bool need_reconnect:1; /* connection reset, uid now invalid */
>> diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
>> index 13c854e..0dbc51c 100644
>> --- a/fs/cifs/cifssmb.c
>> +++ b/fs/cifs/cifssmb.c
>> @@ -486,7 +486,7 @@ CIFSSMBNegotiate(unsigned int xid, struct cifsSesInfo *ses)
>>
>> if (rsp->EncryptionKeyLength ==
>> cpu_to_le16(CIFS_CRYPTO_KEY_SIZE)) {
>> - memcpy(server->cryptKey, rsp->EncryptionKey,
>> + memcpy(ses->cryptKey, rsp->EncryptionKey,
>> CIFS_CRYPTO_KEY_SIZE);
>> } else if (server->secMode & SECMODE_PW_ENCRYPT) {
>> rc = -EIO; /* need cryptkey unless plain text */
>> @@ -557,7 +557,7 @@ CIFSSMBNegotiate(unsigned int xid, struct cifsSesInfo *ses)
>> server->timeAdj = (int)(__s16)le16_to_cpu(pSMBr->ServerTimeZone);
>> server->timeAdj *= 60;
>> if (pSMBr->EncryptionKeyLength == CIFS_CRYPTO_KEY_SIZE) {
>> - memcpy(server->cryptKey, pSMBr->u.EncryptionKey,
>> + memcpy(ses->cryptKey, pSMBr->u.EncryptionKey,
>> CIFS_CRYPTO_KEY_SIZE);
>> } else if ((pSMBr->hdr.Flags2 & SMBFLG2_EXT_SEC)
>> && (pSMBr->EncryptionKeyLength == 0)) {
>> diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
>> index f6a3091..12a6e20 100644
>> --- a/fs/cifs/connect.c
>> +++ b/fs/cifs/connect.c
>> @@ -200,6 +200,7 @@ cifs_reconnect(struct TCP_Server_Info *server)
>> if (server->tcpStatus != CifsExiting)
>> server->tcpStatus = CifsGood;
>> server->sequence_number = 0;
>> + server->session_estab = false;
>> spin_unlock(&GlobalMid_Lock);
>> /* atomic_set(&server->inFlight,0);*/
>> wake_up(&server->response_q);
>> @@ -1616,6 +1617,7 @@ cifs_get_tcp_session(struct smb_vol *volume_info)
>> volume_info->source_rfc1001_name, RFC1001_NAME_LEN_WITH_NULL);
>> memcpy(tcp_ses->server_RFC1001_name,
>> volume_info->target_rfc1001_name, RFC1001_NAME_LEN_WITH_NULL);
>> + tcp_ses->session_estab = false;
>> tcp_ses->sequence_number = 0;
>> INIT_LIST_HEAD(&tcp_ses->tcp_ses_list);
>> INIT_LIST_HEAD(&tcp_ses->smb_ses_list);
>> @@ -2914,14 +2916,13 @@ CIFSTCon(unsigned int xid, struct cifsSesInfo *ses,
>> #ifdef CONFIG_CIFS_WEAK_PW_HASH
>> if ((global_secflags & CIFSSEC_MAY_LANMAN) &&
>> (ses->server->secType == LANMAN))
>> - calc_lanman_hash(tcon->password, ses->server->cryptKey,
>> + calc_lanman_hash(tcon->password, ses->cryptKey,
>> ses->server->secMode &
>> SECMODE_PW_ENCRYPT ? true : false,
>> bcc_ptr);
>> else
>> #endif /* CIFS_WEAK_PW_HASH */
>> - SMBNTencrypt(tcon->password, ses->server->cryptKey,
>> - bcc_ptr);
>> + SMBNTencrypt(tcon->password, ses->cryptKey, bcc_ptr);
>>
>> bcc_ptr += CIFS_SESS_KEY_SIZE;
>> if (ses->capabilities & CAP_UNICODE) {
>> diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
>> index 9148fd8..d632331 100644
>> --- a/fs/cifs/sess.c
>> +++ b/fs/cifs/sess.c
>> @@ -402,7 +402,7 @@ static int decode_ntlmssp_challenge(char *bcc_ptr, int blob_len,
>> return -EINVAL;
>> }
>>
>> - memcpy(ses->server->cryptKey, pblob->Challenge, CIFS_CRYPTO_KEY_SIZE);
>> + memcpy(ses->cryptKey, pblob->Challenge, CIFS_CRYPTO_KEY_SIZE);
>> /* BB we could decode pblob->NegotiateFlags; some may be useful */
>> /* In particular we can examine sign flags */
>> /* BB spec says that if AvId field of MsvAvTimestamp is populated then
>> @@ -672,7 +672,7 @@ ssetup_ntlmssp_authenticate:
>> /* BB calculate hash with password */
>> /* and copy into bcc */
>>
>> - calc_lanman_hash(ses->password, ses->server->cryptKey,
>> + calc_lanman_hash(ses->password, ses->cryptKey,
>> ses->server->secMode & SECMODE_PW_ENCRYPT ?
>> true : false, lnm_session_key);
>>
>> @@ -699,12 +699,11 @@ ssetup_ntlmssp_authenticate:
>> cpu_to_le16(CIFS_SESS_KEY_SIZE);
>>
>> /* calculate session key */
>> - SMBNTencrypt(ses->password, ses->server->cryptKey,
>> - ntlm_session_key);
>> + SMBNTencrypt(ses->password, ses->cryptKey, ntlm_session_key);
>>
>> if (first_time) /* should this be moved into common code
>> - with similar ntlmv2 path? */
>> - cifs_calculate_session_key(&ses->server->session_key,
>> + with similar ntlmv2 path? */
>> + cifs_calculate_session_key(&ses->auth_key,
>> ntlm_session_key, ses->password);
>> /* copy session key */
>>
>> @@ -794,15 +793,15 @@ ssetup_ntlmssp_authenticate:
>> }
>> /* bail out if key is too long */
>> if (msg->sesskey_len >
>> - sizeof(ses->server->session_key.data.krb5)) {
>> + sizeof(ses->auth_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->session_key.len = msg->sesskey_len;
>> - memcpy(ses->server->session_key.data.krb5,
>> + ses->auth_key.len = msg->sesskey_len;
>> + memcpy(ses->auth_key.data.krb5,
>> msg->data, msg->sesskey_len);
>> }
>> pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
>
> Ok, so basically this moves all of the session key data structures from
> the server to session. Once you calculate the key however and have a
> successful session setup, don't you need to copy that key from the
> session to the server? Where does that happen?
>
> --
> Jeff Layton <jlayton@xxxxxxxxxx>
>
Jeff, that code is in 5/7 patch.
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