On Mon, 4 Oct 2010 18:13:23 -0500
Shirish Pargaonkar <shirishpargaonkar@xxxxxxxxx> wrote:
> On Mon, Oct 4, 2010 at 8:18 AM, Jeff Layton <jlayton@xxxxxxxxxx> wrote:
> > On Mon, 4 Oct 2010 08:00:57 -0500
> > Shirish Pargaonkar <shirishpargaonkar@xxxxxxxxx> wrote:
> >
> >> 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"
> >
> > That makes this far more difficult and time consuming to review than a
> > series of discrete changes that leave the tree in a non-broken state.
> > I'll try to get to it when I'm able.
> >
> > --
> > Jeff Layton <jlayton@xxxxxxxxxx>
> >
>
> Now that I think about them more, only patches 3/7 and 5/7 are incremental and
> qualify for non-discrete.
> I could combine 3/7 and5/7 together to make 3/6. I was trying to keep
> the patches
> smaller wherever I could.
Small patches are easier to review, but that benefit is generally lost
when they aren't bisectable. If I have to look at multiple files to
tell whether the patch does what it says it's going to, then there's no
benefit to breaking it up.
Change one thing at a time and strive to keep everything working after
your patch is applied. Each patch should have a clear goal in mind and
that should be stated in the patch description. This is preferred even
if you're changing the same bit of code over and over again.
--
Jeff Layton <jlayton@xxxxxxxxxx>
--
To unsubscribe from this list: send the line "unsubscribe linux-cifs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
