Commit cc87c47d authored by Sachin Prabhu's avatar Sachin Prabhu Committed by Steve French
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cifs: Separate rawntlmssp auth from CIFS_SessSetup()



Separate rawntlmssp authentication from CIFS_SessSetup(). Also cleanup
CIFS_SessSetup() since we no longer do any auth within it.

Signed-off-by: default avatarSachin Prabhu <sprabhu@redhat.com>
Reviewed-by: default avatarShirish Pargaonkar <spargaonkar@suse.com>
Signed-off-by: default avatarSteve French <smfrench@gmail.com>
parent ee03c646
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+263 −227
Original line number Diff line number Diff line
@@ -1113,156 +1113,185 @@ sess_auth_kerberos(struct sess_data *sess_data)
}
#endif /* ! CONFIG_CIFS_UPCALL */

int
CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
	       const struct nls_table *nls_cp)
/*
 * The required kvec buffers have to be allocated before calling this
 * function.
 */
static int
_sess_auth_rawntlmssp_assemble_req(struct sess_data *sess_data)
{
	int rc = 0;
	int wct;
	struct smb_hdr *smb_buf;
	char *bcc_ptr;
	char *str_area;
	SESSION_SETUP_ANDX *pSMB;
	struct cifs_ses *ses = sess_data->ses;
	__u32 capabilities;
	__u16 count;
	int resp_buf_type;
	struct kvec iov[3];
	enum securityEnum type;
	__u16 action, bytes_remaining;
	__le32 phase = NtLmNegotiate; /* NTLMSSP, if needed, is multistage */
	u16 blob_len;
	char *ntlmsspblob = NULL;
	struct sess_data *sess_data;
	char *bcc_ptr;

	if (ses == NULL) {
		WARN(1, "%s: ses == NULL!", __func__);
		return -EINVAL;
	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
	smb_buf = (struct smb_hdr *)pSMB;

	capabilities = cifs_ssetup_hdr(ses, pSMB);
	if ((pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) == 0) {
		cifs_dbg(VFS, "NTLMSSP requires Unicode support\n");
		return -ENOSYS;
	}

	sess_data = kzalloc(sizeof(struct sess_data), GFP_KERNEL);
	if (!sess_data)
		return -ENOMEM;
	sess_data->xid = xid;
	sess_data->ses = ses;
	sess_data->buf0_type = CIFS_NO_BUFFER;
	sess_data->nls_cp = (struct nls_table *) nls_cp;
	pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
	capabilities |= CAP_EXTENDED_SECURITY;
	pSMB->req.Capabilities |= cpu_to_le32(capabilities);

	type = select_sectype(ses->server, ses->sectype);
	cifs_dbg(FYI, "sess setup type %d\n", type);
	if (type == Unspecified) {
		cifs_dbg(VFS,
			"Unable to select appropriate authentication method!");
		return -EINVAL;
	bcc_ptr = sess_data->iov[2].iov_base;
	/* unicode strings must be word aligned */
	if ((sess_data->iov[0].iov_len + sess_data->iov[1].iov_len) % 2) {
		*bcc_ptr = 0;
		bcc_ptr++;
	}
	unicode_oslm_strings(&bcc_ptr, sess_data->nls_cp);

	switch (type) {
	case LANMAN:
		sess_auth_lanman(sess_data);
		goto out;
	case NTLM:
		sess_auth_ntlm(sess_data);
		goto out;
	case NTLMv2:
		sess_auth_ntlmv2(sess_data);
		goto out;
	case Kerberos:
		sess_auth_kerberos(sess_data);
		goto out;
	default:
		cifs_dbg(FYI, "Continuing with CIFS_SessSetup\n");
	sess_data->iov[2].iov_len = (long) bcc_ptr -
					(long) sess_data->iov[2].iov_base;

	return 0;
}

	if (type == RawNTLMSSP) {
		/* if memory allocation is successful, caller of this function
static void
sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data);

static void
sess_auth_rawntlmssp_negotiate(struct sess_data *sess_data)
{
	int rc;
	struct smb_hdr *smb_buf;
	SESSION_SETUP_ANDX *pSMB;
	struct cifs_ses *ses = sess_data->ses;
	__u16 bytes_remaining;
	char *bcc_ptr;
	u16 blob_len;

	cifs_dbg(FYI, "rawntlmssp session setup negotiate phase\n");

	/*
	 * if memory allocation is successful, caller of this function
	 * frees it.
	 */
	ses->ntlmssp = kmalloc(sizeof(struct ntlmssp_auth), GFP_KERNEL);
		if (!ses->ntlmssp)
			return -ENOMEM;
	if (!ses->ntlmssp) {
		rc = -ENOMEM;
		goto out;
	}
	ses->ntlmssp->sesskey_per_smbsess = false;

	}
	/* wct = 12 */
	rc = sess_alloc_buffer(sess_data, 12);
	if (rc)
		goto out;

ssetup_ntlmssp_authenticate:
	if (phase == NtLmChallenge)
		phase = NtLmAuthenticate; /* if ntlmssp, now final phase */
	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;

	/* same size: negotiate or auth, NTLMSSP or extended security */
	wct = 12;
	/* Build security blob before we assemble the request */
	build_ntlmssp_negotiate_blob(pSMB->req.SecurityBlob, ses);
	sess_data->iov[1].iov_len = sizeof(NEGOTIATE_MESSAGE);
	sess_data->iov[1].iov_base = pSMB->req.SecurityBlob;
	pSMB->req.SecurityBlobLength = cpu_to_le16(sizeof(NEGOTIATE_MESSAGE));

	rc = small_smb_init_no_tc(SMB_COM_SESSION_SETUP_ANDX, wct, ses,
			    (void **)&smb_buf);
	rc = _sess_auth_rawntlmssp_assemble_req(sess_data);
	if (rc)
		return rc;
		goto out;

	pSMB = (SESSION_SETUP_ANDX *)smb_buf;
	rc = sess_sendreceive(sess_data);

	capabilities = cifs_ssetup_hdr(ses, pSMB);
	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;

	/* we will send the SMB in three pieces:
	a fixed length beginning part, an optional
	SPNEGO blob (which can be zero length), and a
	last part which will include the strings
	and rest of bcc area. This allows us to avoid
	a large buffer 17K allocation */
	iov[0].iov_base = (char *)pSMB;
	iov[0].iov_len = be32_to_cpu(smb_buf->smb_buf_length) + 4;

	/* setting this here allows the code at the end of the function
	   to free the request buffer if there's an error */
	resp_buf_type = CIFS_SMALL_BUFFER;
	/* If true, rc here is expected and not an error */
	if (sess_data->buf0_type != CIFS_NO_BUFFER &&
	    smb_buf->Status.CifsError ==
			cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))
		rc = 0;

	/* 2000 big enough to fit max user, domain, NOS name etc. */
	str_area = kmalloc(2000, GFP_KERNEL);
	if (str_area == NULL) {
		rc = -ENOMEM;
		goto ssetup_exit;
	if (rc)
		goto out;

	cifs_dbg(FYI, "rawntlmssp session setup challenge phase\n");

	if (smb_buf->WordCount != 4) {
		rc = -EIO;
		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
		goto out;
	}
	bcc_ptr = str_area;

	iov[1].iov_base = NULL;
	iov[1].iov_len = 0;
	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);

	if (type == RawNTLMSSP) {
		if ((pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) == 0) {
			cifs_dbg(VFS, "NTLMSSP requires Unicode support\n");
			rc = -ENOSYS;
			goto ssetup_exit;
	bytes_remaining = get_bcc(smb_buf);
	bcc_ptr = pByteArea(smb_buf);

	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
	if (blob_len > bytes_remaining) {
		cifs_dbg(VFS, "bad security blob length %d\n",
				blob_len);
		rc = -EINVAL;
		goto out;
	}

		cifs_dbg(FYI, "ntlmssp session setup phase %d\n", phase);
		pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
		capabilities |= CAP_EXTENDED_SECURITY;
		pSMB->req.Capabilities |= cpu_to_le32(capabilities);
		switch(phase) {
		case NtLmNegotiate:
			build_ntlmssp_negotiate_blob(
				pSMB->req.SecurityBlob, ses);
			iov[1].iov_len = sizeof(NEGOTIATE_MESSAGE);
			iov[1].iov_base = pSMB->req.SecurityBlob;
			pSMB->req.SecurityBlobLength =
				cpu_to_le16(sizeof(NEGOTIATE_MESSAGE));
			break;
		case NtLmAuthenticate:
	rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses);
out:
	sess_free_buffer(sess_data);

	if (!rc) {
		sess_data->func = sess_auth_rawntlmssp_authenticate;
		return;
	}

	/* Else error. Cleanup */
	kfree(ses->auth_key.response);
	ses->auth_key.response = NULL;
	kfree(ses->ntlmssp);
	ses->ntlmssp = NULL;

	sess_data->func = NULL;
	sess_data->result = rc;
}

static void
sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data)
{
	int rc;
	struct smb_hdr *smb_buf;
	SESSION_SETUP_ANDX *pSMB;
	struct cifs_ses *ses = sess_data->ses;
	__u16 bytes_remaining;
	char *bcc_ptr;
	char *ntlmsspblob = NULL;
	u16 blob_len;

	cifs_dbg(FYI, "rawntlmssp session setup authenticate phase\n");

	/* wct = 12 */
	rc = sess_alloc_buffer(sess_data, 12);
	if (rc)
		goto out;

	/* Build security blob before we assemble the request */
	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
	smb_buf = (struct smb_hdr *)pSMB;
	/*
	 * 5 is an empirical value, large enough to hold
	 * authenticate message plus max 10 of av paris,
	 * domain, user, workstation names, flags, etc.
	 */
			ntlmsspblob = kzalloc(
				5*sizeof(struct _AUTHENTICATE_MESSAGE),
	ntlmsspblob = kzalloc(5*sizeof(struct _AUTHENTICATE_MESSAGE),
				GFP_KERNEL);
	if (!ntlmsspblob) {
		rc = -ENOMEM;
				goto ssetup_exit;
		goto out;
	}

	rc = build_ntlmssp_auth_blob(ntlmsspblob,
						&blob_len, ses, nls_cp);
					&blob_len, ses, sess_data->nls_cp);
	if (rc)
				goto ssetup_exit;
			iov[1].iov_len = blob_len;
			iov[1].iov_base = ntlmsspblob;
		goto out_free_ntlmsspblob;
	sess_data->iov[1].iov_len = blob_len;
	sess_data->iov[1].iov_base = ntlmsspblob;
	pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len);
	/*
	 * Make sure that we tell the server that we are using
@@ -1270,84 +1299,39 @@ ssetup_ntlmssp_authenticate:
	 * (challenge)
	 */
	smb_buf->Uid = ses->Suid;
			break;
		default:
			cifs_dbg(VFS, "invalid phase %d\n", phase);
			rc = -ENOSYS;
			goto ssetup_exit;
		}
		/* unicode strings must be word aligned */
		if ((iov[0].iov_len + iov[1].iov_len) % 2) {
			*bcc_ptr = 0;
			bcc_ptr++;
		}
		unicode_oslm_strings(&bcc_ptr, nls_cp);
	} else {
		cifs_dbg(VFS, "secType %d not supported!\n", type);
		rc = -ENOSYS;
		goto ssetup_exit;
	}

	iov[2].iov_base = str_area;
	iov[2].iov_len = (long) bcc_ptr - (long) str_area;

	count = iov[1].iov_len + iov[2].iov_len;
	smb_buf->smb_buf_length =
		cpu_to_be32(be32_to_cpu(smb_buf->smb_buf_length) + count);

	put_bcc(count, smb_buf);

	rc = SendReceive2(xid, ses, iov, 3 /* num_iovecs */, &resp_buf_type,
			  CIFS_LOG_ERROR);
	/* SMB request buf freed in SendReceive2 */

	pSMB = (SESSION_SETUP_ANDX *)iov[0].iov_base;
	smb_buf = (struct smb_hdr *)iov[0].iov_base;
	rc = _sess_auth_rawntlmssp_assemble_req(sess_data);
	if (rc)
		goto out_free_ntlmsspblob;

	if ((type == RawNTLMSSP) && (resp_buf_type != CIFS_NO_BUFFER) &&
	    (smb_buf->Status.CifsError ==
			cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))) {
		if (phase != NtLmNegotiate) {
			cifs_dbg(VFS, "Unexpected more processing error\n");
			goto ssetup_exit;
		}
		/* NTLMSSP Negotiate sent now processing challenge (response) */
		phase = NtLmChallenge; /* process ntlmssp challenge */
		rc = 0; /* MORE_PROC rc is not an error here, but expected */
	}
	rc = sess_sendreceive(sess_data);
	if (rc)
		goto ssetup_exit;
		goto out_free_ntlmsspblob;

	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
	if (smb_buf->WordCount != 4) {
		rc = -EIO;
		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
		goto ssetup_exit;
		goto out_free_ntlmsspblob;
	}
	action = le16_to_cpu(pSMB->resp.Action);
	if (action & GUEST_LOGIN)

	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
	/* response can have either 3 or 4 word count - Samba sends 3 */
	/* and lanman response is 3 */

	bytes_remaining = get_bcc(smb_buf);
	bcc_ptr = pByteArea(smb_buf);

	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
	if (blob_len > bytes_remaining) {
		cifs_dbg(VFS, "bad security blob length %d\n",
				blob_len);
		rc = -EINVAL;
		goto ssetup_exit;
	}
	if (phase == NtLmChallenge) {
		rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses);
		if (rc)
			goto ssetup_exit;
		goto out_free_ntlmsspblob;
	}
	bcc_ptr += blob_len;
	bytes_remaining -= blob_len;


	/* BB check if Unicode and decode strings */
	if (bytes_remaining == 0) {
		/* no string area to decode, do nothing */
@@ -1357,61 +1341,113 @@ ssetup_ntlmssp_authenticate:
			++bcc_ptr;
			--bytes_remaining;
		}
		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses, nls_cp);
		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
				      sess_data->nls_cp);
	} else {
		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses, nls_cp);
		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
				    sess_data->nls_cp);
	}

ssetup_exit:
	kfree(str_area);
out_free_ntlmsspblob:
	kfree(ntlmsspblob);
	ntlmsspblob = NULL;
	if (resp_buf_type == CIFS_SMALL_BUFFER) {
		cifs_dbg(FYI, "ssetup freeing small buf %p\n", iov[0].iov_base);
		cifs_small_buf_release(iov[0].iov_base);
	} else if (resp_buf_type == CIFS_LARGE_BUFFER)
		cifs_buf_release(iov[0].iov_base);
out:
	sess_free_buffer(sess_data);

	/* if ntlmssp, and negotiate succeeded, proceed to authenticate phase */
	if ((phase == NtLmChallenge) && (rc == 0))
		goto ssetup_ntlmssp_authenticate;
	 if (!rc)
		rc = sess_establish_session(sess_data);

	if (!rc) {
		mutex_lock(&ses->server->srv_mutex);
		if (!ses->server->session_estab) {
			if (ses->server->sign) {
				ses->server->session_key.response =
					kmemdup(ses->auth_key.response,
					ses->auth_key.len, GFP_KERNEL);
				if (!ses->server->session_key.response) {
					rc = -ENOMEM;
					mutex_unlock(&ses->server->srv_mutex);
					goto keycp_exit;
	/* Cleanup */
	kfree(ses->auth_key.response);
	ses->auth_key.response = NULL;
	kfree(ses->ntlmssp);
	ses->ntlmssp = NULL;

	sess_data->func = NULL;
	sess_data->result = rc;
}
				ses->server->session_key.len =
							ses->auth_key.len;

int select_sec(struct cifs_ses *ses, struct sess_data *sess_data)
{
	int type;

	type = select_sectype(ses->server, ses->sectype);
	cifs_dbg(FYI, "sess setup type %d\n", type);
	if (type == Unspecified) {
		cifs_dbg(VFS,
			"Unable to select appropriate authentication method!");
		return -EINVAL;
	}
			ses->server->sequence_number = 0x2;
			ses->server->session_estab = true;

	switch (type) {
	case LANMAN:
		/* LANMAN and plaintext are less secure and off by default.
		 * So we make this explicitly be turned on in kconfig (in the
		 * build) and turned on at runtime (changed from the default)
		 * in proc/fs/cifs or via mount parm.  Unfortunately this is
		 * needed for old Win (e.g. Win95), some obscure NAS and OS/2 */
#ifdef CONFIG_CIFS_WEAK_PW_HASH
		sess_data->func = sess_auth_lanman;
		break;
#else
		return -EOPNOTSUPP;
#endif
	case NTLM:
		sess_data->func = sess_auth_ntlm;
		break;
	case NTLMv2:
		sess_data->func = sess_auth_ntlmv2;
		break;
	case Kerberos:
#ifdef CONFIG_CIFS_UPCALL
		sess_data->func = sess_auth_kerberos;
		break;
#else
		cifs_dbg(VFS, "Kerberos negotiated but upcall support disabled!\n");
		return -ENOSYS;
		break;
#endif /* CONFIG_CIFS_UPCALL */
	case RawNTLMSSP:
		sess_data->func = sess_auth_rawntlmssp_negotiate;
		break;
	default:
		cifs_dbg(VFS, "secType %d not supported!\n", type);
		return -ENOSYS;
	}
		mutex_unlock(&ses->server->srv_mutex);

		cifs_dbg(FYI, "CIFS session established successfully\n");
		spin_lock(&GlobalMid_Lock);
		ses->status = CifsGood;
		ses->need_reconnect = false;
		spin_unlock(&GlobalMid_Lock);
	return 0;
}

keycp_exit:
	kfree(ses->auth_key.response);
	ses->auth_key.response = NULL;
	kfree(ses->ntlmssp);
int CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
		    const struct nls_table *nls_cp)
{
	int rc = 0;
	struct sess_data *sess_data;

	return rc;
	if (ses == NULL) {
		WARN(1, "%s: ses == NULL!", __func__);
		return -EINVAL;
	}

out:
	sess_data = kzalloc(sizeof(struct sess_data), GFP_KERNEL);
	if (!sess_data)
		return -ENOMEM;

	rc = select_sec(ses, sess_data);
	if (rc)
		goto out;

	sess_data->xid = xid;
	sess_data->ses = ses;
	sess_data->buf0_type = CIFS_NO_BUFFER;
	sess_data->nls_cp = (struct nls_table *) nls_cp;

	while (sess_data->func)
		sess_data->func(sess_data);

	/* Store result before we free sess_data */
	rc = sess_data->result;

out:
	kfree(sess_data);
	return rc;
}