On Mon, Oct 4, 2010 at 7:53 AM, Jeff Layton <jlayton@xxxxxxxxxx> wrote:
> On Mon, 4 Oct 2010 07:52:08 -0500
> Shirish Pargaonkar <shirishpargaonkar@xxxxxxxxx> wrote:
>
>> 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.
>
> Ok, so to be clear this patchset is "all or nothing"? If you apply just
> part of them, you'll have a broken tree?
>
> --
> Jeff Layton <jlayton@xxxxxxxxxx>
>
Jeff, yes. There are are ifs and buts, but overall answer is, yes,
"all or nothing"
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