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>
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