Commit message: s3: Fix an uninitialized variable read

Found by Laurent Gaffie <laurent.gaffie@gmail.com>

Thanks for that,

Volker

Fix bug #7254 (An uninitialized variable read could cause an smbd crash).
CVE: CVE-2010-1642
CWE: CWE-119
Vulnerability description: The reply_sesssetup_and_X_spnego function in sesssetup.c in smbd in Samba before 3.4.8 and 3.5.x before 3.5.2 allows remote attackers to trigger an out-of-bounds read, and cause a denial of service (process crash), via a \xff\xff security blob length in a Session Setup AndX request.

Project: samba
File: sesssetup.c

static NTSTATUS check_guest_password(auth_serversupplied_info **server_info)
{
	struct auth_context *auth_context;
	auth_usersupplied_info *user_info = NULL;

	NTSTATUS nt_status;
	unsigned char chal[8];

	ZERO_STRUCT(chal);

	DEBUG(3,("Got anonymous request\n"));

	if (!NT_STATUS_IS_OK(nt_status = make_auth_context_fixed(&auth_context,
					chal))) {
		return nt_status;
	}

	if (!make_user_info_guest(&user_info)) {
		(auth_context->free)(&auth_context);
		return NT_STATUS_NO_MEMORY;
	}

	nt_status = auth_context->check_ntlm_password(auth_context,
						user_info,
						server_info);
	(auth_context->free)(&auth_context);
	free_user_info(&user_info);
	return nt_status;
}

Project: samba
File: sesssetup.c

static NTSTATUS check_spnego_blob_complete(struct smbd_server_connection *sconn,
					   uint16 smbpid, uint16 vuid,
					   DATA_BLOB *pblob)
{
	struct pending_auth_data *pad = NULL;
	ASN1_DATA *data;
	size_t needed_len = 0;

	pad = get_pending_auth_data(sconn, smbpid);

	/* Ensure we have some data. */
	if (pblob->length == 0) {
		/* Caller can cope. */
		DEBUG(2,("check_spnego_blob_complete: zero blob length !\n"));
		delete_partial_auth(sconn, pad);
		return NT_STATUS_OK;
	}

	/* Were we waiting for more data ? */
	if (pad) {
		DATA_BLOB tmp_blob;
		size_t copy_len = MIN(65536, pblob->length);

		/* Integer wrap paranoia.... */

		if (pad->partial_data.length + copy_len <
				pad->partial_data.length ||
		    pad->partial_data.length + copy_len < copy_len) {

			DEBUG(2,("check_spnego_blob_complete: integer wrap "
				"pad->partial_data.length = %u, "
				"copy_len = %u\n",
				(unsigned int)pad->partial_data.length,
				(unsigned int)copy_len ));

			delete_partial_auth(sconn, pad);
			return NT_STATUS_INVALID_PARAMETER;
		}

		DEBUG(10,("check_spnego_blob_complete: "
			"pad->partial_data.length = %u, "
			"pad->needed_len = %u, "
			"copy_len = %u, "
			"pblob->length = %u,\n",
			(unsigned int)pad->partial_data.length,
			(unsigned int)pad->needed_len,
			(unsigned int)copy_len,
			(unsigned int)pblob->length ));

		tmp_blob = data_blob(NULL,
				pad->partial_data.length + copy_len);

		/* Concatenate the two (up to copy_len) bytes. */
		memcpy(tmp_blob.data,
			pad->partial_data.data,
			pad->partial_data.length);
		memcpy(tmp_blob.data + pad->partial_data.length,
			pblob->data,
			copy_len);

		/* Replace the partial data. */
		data_blob_free(&pad->partial_data);
		pad->partial_data = tmp_blob;
		ZERO_STRUCT(tmp_blob);

		/* Are we done ? */
		if (pblob->length >= pad->needed_len) {
			/* Yes, replace pblob. */
			data_blob_free(pblob);
			*pblob = pad->partial_data;
			ZERO_STRUCT(pad->partial_data);
			delete_partial_auth(sconn, pad);
			return NT_STATUS_OK;
		}

		/* Still need more data. */
		pad->needed_len -= copy_len;
		return NT_STATUS_MORE_PROCESSING_REQUIRED;
	}

	if ((pblob->data[0] != ASN1_APPLICATION(0)) &&
	    (pblob->data[0] != ASN1_CONTEXT(1))) {
		/* Not something we can determine the
		 * length of.
		 */
		return NT_STATUS_OK;
	}

	/* This is a new SPNEGO sessionsetup - see if
	 * the data given in this blob is enough.
	 */

	data = asn1_init(NULL);
	if (data == NULL) {
		return NT_STATUS_NO_MEMORY;
	}

	asn1_load(data, *pblob);
	asn1_start_tag(data, pblob->data[0]);
	if (data->has_error || data->nesting == NULL) {
		asn1_free(data);
		/* Let caller catch. */
		return NT_STATUS_OK;
	}

	/* Integer wrap paranoia.... */

	if (data->nesting->taglen + data->nesting->start < data->nesting->taglen ||
	    data->nesting->taglen + data->nesting->start < data->nesting->start) {

		DEBUG(2,("check_spnego_blob_complete: integer wrap "
			"data.nesting->taglen = %u, "
			"data.nesting->start = %u\n",
			(unsigned int)data->nesting->taglen,
			(unsigned int)data->nesting->start ));

		asn1_free(data);
		return NT_STATUS_INVALID_PARAMETER;
	}

	/* Total length of the needed asn1 is the tag length
	 * plus the current offset. */

	needed_len = data->nesting->taglen + data->nesting->start;
	asn1_free(data);

	DEBUG(10,("check_spnego_blob_complete: needed_len = %u, "
		"pblob->length = %u\n",
		(unsigned int)needed_len,
		(unsigned int)pblob->length ));

	if (needed_len <= pblob->length) {
		/* Nothing to do - blob is complete. */
		return NT_STATUS_OK;
	}

	/* Refuse the blob if it's bigger than 64k. */
	if (needed_len > 65536) {
		DEBUG(2,("check_spnego_blob_complete: needed_len "
			"too large (%u)\n",
			(unsigned int)needed_len ));
		return NT_STATUS_INVALID_PARAMETER;
	}

	/* We must store this blob until complete. */
	if (!(pad = SMB_MALLOC_P(struct pending_auth_data))) {
		return NT_STATUS_NO_MEMORY;
	}
	pad->needed_len = needed_len - pblob->length;
	pad->partial_data = data_blob(pblob->data, pblob->length);
	if (pad->partial_data.data == NULL) {
		SAFE_FREE(pad);
		return NT_STATUS_NO_MEMORY;
	}
	pad->smbpid = smbpid;
	pad->vuid = vuid;
	DLIST_ADD(sconn->smb1.pd_list, pad);

	return NT_STATUS_MORE_PROCESSING_REQUIRED;
}

Project: samba
File: sesssetup.c

static void delete_partial_auth(struct smbd_server_connection *sconn,
				struct pending_auth_data *pad)
{
	if (!pad) {
		return;
	}
	DLIST_REMOVE(sconn->smb1.pd_list, pad);
	data_blob_free(&pad->partial_data);
	SAFE_FREE(pad);
}

Project: samba
File: sesssetup.c

static NTSTATUS do_map_to_guest(NTSTATUS status,
				auth_serversupplied_info **server_info,
				const char *user, const char *domain)
{
	if (NT_STATUS_EQUAL(status, NT_STATUS_NO_SUCH_USER)) {
		if ((lp_map_to_guest() == MAP_TO_GUEST_ON_BAD_USER) ||
		    (lp_map_to_guest() == MAP_TO_GUEST_ON_BAD_PASSWORD)) {
			DEBUG(3,("No such user %s [%s] - using guest account\n",
				 user, domain));
			status = make_server_info_guest(NULL, server_info);
		}
	}

	if (NT_STATUS_EQUAL(status, NT_STATUS_WRONG_PASSWORD)) {
		if (lp_map_to_guest() == MAP_TO_GUEST_ON_BAD_PASSWORD) {
			DEBUG(3,("Registered username %s for guest access\n",
				user));
			status = make_server_info_guest(NULL, server_info);
		}
	}

	return status;
}

Project: samba
File: sesssetup.c

static struct pending_auth_data *get_pending_auth_data(
		struct smbd_server_connection *sconn,
		uint16_t smbpid)
{
	struct pending_auth_data *pad;
/*
 * NOTE: using the smbpid here is completely wrong...
 *       see [MS-SMB]
 *       3.3.5.3 Receiving an SMB_COM_SESSION_SETUP_ANDX Request
 */
	for (pad = sconn->smb1.pd_list; pad; pad = pad->next) {
		if (pad->smbpid == smbpid) {
			break;
		}
	}
	return pad;
}

Project: samba
File: sesssetup.c

NTSTATUS parse_spnego_mechanisms(DATA_BLOB blob_in,
		DATA_BLOB *pblob_out,
		char **kerb_mechOID)
{
	char *OIDs[ASN1_MAX_OIDS];
	int i;
	NTSTATUS ret = NT_STATUS_OK;

	*kerb_mechOID = NULL;

	/* parse out the OIDs and the first sec blob */
	if (!parse_negTokenTarg(blob_in, OIDs, pblob_out)) {
		return NT_STATUS_LOGON_FAILURE;
	}

	/* only look at the first OID for determining the mechToken --
	   according to RFC2478, we should choose the one we want
	   and renegotiate, but i smell a client bug here..

	   Problem observed when connecting to a member (samba box)
	   of an AD domain as a user in a Samba domain.  Samba member
	   server sent back krb5/mskrb5/ntlmssp as mechtypes, but the
	   client (2ksp3) replied with ntlmssp/mskrb5/krb5 and an
	   NTLMSSP mechtoken.                 --jerry              */

#ifdef HAVE_KRB5
	if (strcmp(OID_KERBEROS5, OIDs[0]) == 0 ||
	    strcmp(OID_KERBEROS5_OLD, OIDs[0]) == 0) {
		*kerb_mechOID = SMB_STRDUP(OIDs[0]);
		if (*kerb_mechOID == NULL) {
			ret = NT_STATUS_NO_MEMORY;
		}
	}
#endif

	for (i=0;OIDs[i];i++) {
		DEBUG(5,("parse_spnego_mechanisms: Got OID %s\n", OIDs[i]));
		talloc_free(OIDs[i]);
	}
	return ret;
}

Project: samba
File: sesssetup.c

static int push_signature(uint8 **outbuf)
{
	char *lanman;
	int result, tmp;

	result = 0;

	tmp = message_push_string(outbuf, "Unix", STR_TERMINATE);

	if (tmp == -1) return -1;
	result += tmp;

	if (asprintf(&lanman, "Samba %s", samba_version_string()) != -1) {
		tmp = message_push_string(outbuf, lanman, STR_TERMINATE);
		SAFE_FREE(lanman);
	}
	else {
		tmp = message_push_string(outbuf, "Samba", STR_TERMINATE);
	}

	if (tmp == -1) return -1;
	result += tmp;

	tmp = message_push_string(outbuf, lp_workgroup(), STR_TERMINATE);

	if (tmp == -1) return -1;
	result += tmp;

	return result;
}

Project: samba
File: sesssetup.c

void reply_sesssetup_and_X(struct smb_request *req)
{
	int sess_vuid;
	int smb_bufsize;
	DATA_BLOB lm_resp;
	DATA_BLOB nt_resp;
	DATA_BLOB plaintext_password;
	char *tmp;
	const char *user;
	fstring sub_user; /* Sainitised username for substituion */
	const char *domain;
	const char *native_os;
	const char *native_lanman;
	const char *primary_domain;
	auth_usersupplied_info *user_info = NULL;
	auth_serversupplied_info *server_info = NULL;
	uint16 smb_flag2 = req->flags2;

	NTSTATUS nt_status;
	struct smbd_server_connection *sconn = smbd_server_conn;

	bool doencrypt = sconn->smb1.negprot.encrypted_passwords;

	START_PROFILE(SMBsesssetupX);

	ZERO_STRUCT(lm_resp);
	ZERO_STRUCT(nt_resp);
	ZERO_STRUCT(plaintext_password);

	DEBUG(3,("wct=%d flg2=0x%x\n", req->wct, req->flags2));

	/* a SPNEGO session setup has 12 command words, whereas a normal
	   NT1 session setup has 13. See the cifs spec. */
	if (req->wct == 12 &&
	    (req->flags2 & FLAGS2_EXTENDED_SECURITY)) {

		if (!sconn->smb1.negprot.spnego) {
			DEBUG(0,("reply_sesssetup_and_X:  Rejecting attempt "
				 "at SPNEGO session setup when it was not "
				 "negotiated.\n"));
			reply_nterror(req, nt_status_squash(
					      NT_STATUS_LOGON_FAILURE));
			END_PROFILE(SMBsesssetupX);
			return;
		}

		if (SVAL(req->vwv+4, 0) == 0) {
			setup_new_vc_session();
		}

		reply_sesssetup_and_X_spnego(req);
		END_PROFILE(SMBsesssetupX);
		return;
	}

	smb_bufsize = SVAL(req->vwv+2, 0);

	if (get_Protocol() < PROTOCOL_NT1) {
		uint16 passlen1 = SVAL(req->vwv+7, 0);

		/* Never do NT status codes with protocols before NT1 as we
		 * don't get client caps. */
		remove_from_common_flags2(FLAGS2_32_BIT_ERROR_CODES);

		if ((passlen1 > MAX_PASS_LEN) || (passlen1 > req->buflen)) {
			reply_nterror(req, nt_status_squash(
					      NT_STATUS_INVALID_PARAMETER));
			END_PROFILE(SMBsesssetupX);
			return;
		}

		if (doencrypt) {
			lm_resp = data_blob(req->buf, passlen1);
		} else {
			plaintext_password = data_blob(req->buf, passlen1+1);
			/* Ensure null termination */
			plaintext_password.data[passlen1] = 0;
		}

		srvstr_pull_req_talloc(talloc_tos(), req, &tmp,
				       req->buf + passlen1, STR_TERMINATE);
		user = tmp ? tmp : "";

		domain = "";

	} else {
		uint16 passlen1 = SVAL(req->vwv+7, 0);
		uint16 passlen2 = SVAL(req->vwv+8, 0);
		enum remote_arch_types ra_type = get_remote_arch();
		const uint8_t *p = req->buf;
		const uint8_t *save_p = req->buf;
		uint16 byte_count;


		if(global_client_caps == 0) {
			global_client_caps = IVAL(req->vwv+11, 0);

			if (!(global_client_caps & CAP_STATUS32)) {
				remove_from_common_flags2(
						FLAGS2_32_BIT_ERROR_CODES);
			}

			/* client_caps is used as final determination if
			 * client is NT or Win95. This is needed to return
			 * the correct error codes in some circumstances.
			*/

			if(ra_type == RA_WINNT || ra_type == RA_WIN2K ||
					ra_type == RA_WIN95) {
				if(!(global_client_caps & (CAP_NT_SMBS|
							CAP_STATUS32))) {
					set_remote_arch( RA_WIN95);
				}
			}
		}

		if (!doencrypt) {
			/* both Win95 and WinNT stuff up the password
			 * lengths for non-encrypting systems. Uggh.

			   if passlen1==24 its a win95 system, and its setting
			   the password length incorrectly. Luckily it still
			   works with the default code because Win95 will null
			   terminate the password anyway

			   if passlen1>0 and passlen2>0 then maybe its a NT box
			   and its setting passlen2 to some random value which
			   really stuffs things up. we need to fix that one.  */

			if (passlen1 > 0 && passlen2 > 0 && passlen2 != 24 &&
					passlen2 != 1) {
				passlen2 = 0;
			}
		}

		/* check for nasty tricks */
		if (passlen1 > MAX_PASS_LEN
		    || passlen1 > smbreq_bufrem(req, p)) {
			reply_nterror(req, nt_status_squash(
					      NT_STATUS_INVALID_PARAMETER));
			END_PROFILE(SMBsesssetupX);
			return;
		}

		if (passlen2 > MAX_PASS_LEN
		    || passlen2 > smbreq_bufrem(req, p+passlen1)) {
			reply_nterror(req, nt_status_squash(
					      NT_STATUS_INVALID_PARAMETER));
			END_PROFILE(SMBsesssetupX);
			return;
		}

		/* Save the lanman2 password and the NT md4 password. */

		if ((doencrypt) && (passlen1 != 0) && (passlen1 != 24)) {
			doencrypt = False;
		}

		if (doencrypt) {
			lm_resp = data_blob(p, passlen1);
			nt_resp = data_blob(p+passlen1, passlen2);
		} else if (lp_security() != SEC_SHARE) {
			/*
			 * In share level we should ignore any passwords, so
 			 * only read them if we're not.
 			 */
			char *pass = NULL;
			bool unic= smb_flag2 & FLAGS2_UNICODE_STRINGS;

			if (unic && (passlen2 == 0) && passlen1) {
				/* Only a ascii plaintext password was sent. */
				(void)srvstr_pull_talloc(talloc_tos(),
							req->inbuf,
							req->flags2,
							&pass,
							req->buf,
							passlen1,
							STR_TERMINATE|STR_ASCII);
			} else {
				(void)srvstr_pull_talloc(talloc_tos(),
							req->inbuf,
							req->flags2,
							&pass,
							req->buf,
							unic ? passlen2 : passlen1,
							STR_TERMINATE);
			}
			if (!pass) {
				reply_nterror(req, nt_status_squash(
					      NT_STATUS_INVALID_PARAMETER));
				END_PROFILE(SMBsesssetupX);
				return;
			}
			plaintext_password = data_blob(pass, strlen(pass)+1);
		}

		p += passlen1 + passlen2;

		p += srvstr_pull_req_talloc(talloc_tos(), req, &tmp, p,
					    STR_TERMINATE);
		user = tmp ? tmp : "";

		p += srvstr_pull_req_talloc(talloc_tos(), req, &tmp, p,
					    STR_TERMINATE);
		domain = tmp ? tmp : "";

		p += srvstr_pull_req_talloc(talloc_tos(), req, &tmp, p,
					    STR_TERMINATE);
		native_os = tmp ? tmp : "";

		p += srvstr_pull_req_talloc(talloc_tos(), req, &tmp, p,
					    STR_TERMINATE);
		native_lanman = tmp ? tmp : "";

		/* not documented or decoded by Ethereal but there is one more
		 * string in the extra bytes which is the same as the
		 * PrimaryDomain when using extended security.  Windows NT 4
		 * and 2003 use this string to store the native lanman string.
		 * Windows 9x does not include a string here at all so we have
		 * to check if we have any extra bytes left */

		byte_count = SVAL(req->vwv+13, 0);
		if ( PTR_DIFF(p, save_p) < byte_count) {
			p += srvstr_pull_req_talloc(talloc_tos(), req, &tmp, p,
						    STR_TERMINATE);
			primary_domain = tmp ? tmp : "";
		} else {
			primary_domain = talloc_strdup(talloc_tos(), "null");
		}

		DEBUG(3,("Domain=[%s]  NativeOS=[%s] NativeLanMan=[%s] "
			"PrimaryDomain=[%s]\n",
			domain, native_os, native_lanman, primary_domain));

		if ( ra_type == RA_WIN2K ) {
			if ( strlen(native_lanman) == 0 )
				ra_lanman_string( primary_domain );
			else
				ra_lanman_string( native_lanman );
		}

	}

	if (SVAL(req->vwv+4, 0) == 0) {
		setup_new_vc_session();
	}

	DEBUG(3,("sesssetupX:name=[%s]\\[%s]@[%s]\n",
				domain, user, get_remote_machine_name()));

	if (*user) {
		if (sconn->smb1.negprot.spnego) {

			/* This has to be here, because this is a perfectly
			 * valid behaviour for guest logons :-( */

			DEBUG(0,("reply_sesssetup_and_X:  Rejecting attempt "
				"at 'normal' session setup after "
				"negotiating spnego.\n"));
			reply_nterror(req, nt_status_squash(
					      NT_STATUS_LOGON_FAILURE));
			END_PROFILE(SMBsesssetupX);
			return;
		}
		fstrcpy(sub_user, user);
	} else {
		fstrcpy(sub_user, lp_guestaccount());
	}

	sub_set_smb_name(sub_user);

	reload_services(True);

	if (lp_security() == SEC_SHARE) {
		/* In share level we should ignore any passwords */

		data_blob_free(&lm_resp);
		data_blob_free(&nt_resp);
		data_blob_clear_free(&plaintext_password);

		map_username(sconn, sub_user);
		add_session_user(sconn, sub_user);
		add_session_workgroup(sconn, domain);
		/* Then force it to null for the benfit of the code below */
		user = "";
	}

	if (!*user) {

		nt_status = check_guest_password(&server_info);

	} else if (doencrypt) {
		struct auth_context *negprot_auth_context = NULL;
		negprot_auth_context = sconn->smb1.negprot.auth_context;
		if (!negprot_auth_context) {
			DEBUG(0, ("reply_sesssetup_and_X:  Attempted encrypted "
				"session setup without negprot denied!\n"));
			reply_nterror(req, nt_status_squash(
					      NT_STATUS_LOGON_FAILURE));
			END_PROFILE(SMBsesssetupX);
			return;
		}
		nt_status = make_user_info_for_reply_enc(&user_info, user,
						domain,
						lm_resp, nt_resp);
		if (NT_STATUS_IS_OK(nt_status)) {
			nt_status = negprot_auth_context->check_ntlm_password(
					negprot_auth_context,
					user_info,
					&server_info);
		}
	} else {
		struct auth_context *plaintext_auth_context = NULL;

		nt_status = make_auth_context_subsystem(
				&plaintext_auth_context);

		if (NT_STATUS_IS_OK(nt_status)) {
			uint8_t chal[8];

			plaintext_auth_context->get_ntlm_challenge(
					plaintext_auth_context, chal);

			if (!make_user_info_for_reply(&user_info,
						      user, domain, chal,
						      plaintext_password)) {
				nt_status = NT_STATUS_NO_MEMORY;
			}

			if (NT_STATUS_IS_OK(nt_status)) {
				nt_status = plaintext_auth_context->check_ntlm_password(
						plaintext_auth_context,
						user_info,
						&server_info);

				(plaintext_auth_context->free)(
						&plaintext_auth_context);
			}
		}
	}

	free_user_info(&user_info);

	if (!NT_STATUS_IS_OK(nt_status)) {
		nt_status = do_map_to_guest(nt_status, &server_info,
				user, domain);
	}

	if (!NT_STATUS_IS_OK(nt_status)) {
		data_blob_free(&nt_resp);
		data_blob_free(&lm_resp);
		data_blob_clear_free(&plaintext_password);
		reply_nterror(req, nt_status_squash(nt_status));
		END_PROFILE(SMBsesssetupX);
		return;
	}

	/* Ensure we can't possible take a code path leading to a
	 * null defref. */
	if (!server_info) {
		reply_nterror(req, nt_status_squash(NT_STATUS_LOGON_FAILURE));
		END_PROFILE(SMBsesssetupX);
		return;
	}

	if (!server_info->ptok) {
		nt_status = create_local_token(server_info);

		if (!NT_STATUS_IS_OK(nt_status)) {
			DEBUG(10, ("create_local_token failed: %s\n",
				   nt_errstr(nt_status)));
			data_blob_free(&nt_resp);
			data_blob_free(&lm_resp);
			data_blob_clear_free(&plaintext_password);
			reply_nterror(req, nt_status_squash(nt_status));
			END_PROFILE(SMBsesssetupX);
			return;
		}
	}

	data_blob_clear_free(&plaintext_password);

	/* it's ok - setup a reply */
	reply_outbuf(req, 3, 0);
	if (get_Protocol() >= PROTOCOL_NT1) {
		push_signature(&req->outbuf);
		/* perhaps grab OS version here?? */
	}

	if (server_info->guest) {
		SSVAL(req->outbuf,smb_vwv2,1);
	}

	/* register the name and uid as being validated, so further connections
	   to a uid can get through without a password, on the same VC */

	if (lp_security() == SEC_SHARE) {
		sess_vuid = UID_FIELD_INVALID;
		TALLOC_FREE(server_info);
	} else {
		/* Ignore the initial vuid. */
		sess_vuid = register_initial_vuid(sconn);
		if (sess_vuid == UID_FIELD_INVALID) {
			data_blob_free(&nt_resp);
			data_blob_free(&lm_resp);
			reply_nterror(req, nt_status_squash(
					      NT_STATUS_LOGON_FAILURE));
			END_PROFILE(SMBsesssetupX);
			return;
		}
		/* register_existing_vuid keeps the server info */
		sess_vuid = register_existing_vuid(sconn, sess_vuid,
					server_info,
					nt_resp.data ? nt_resp : lm_resp,
					sub_user);
		if (sess_vuid == UID_FIELD_INVALID) {
			data_blob_free(&nt_resp);
			data_blob_free(&lm_resp);
			reply_nterror(req, nt_status_squash(
					      NT_STATUS_LOGON_FAILURE));
			END_PROFILE(SMBsesssetupX);
			return;
		}

		/* current_user_info is changed on new vuid */
		reload_services( True );
	}

	data_blob_free(&nt_resp);
	data_blob_free(&lm_resp);

	SSVAL(req->outbuf,smb_uid,sess_vuid);
	SSVAL(req->inbuf,smb_uid,sess_vuid);
	req->vuid = sess_vuid;

	if (!sconn->smb1.sessions.done_sesssetup) {
		sconn->smb1.sessions.max_send =
			MIN(sconn->smb1.sessions.max_send,smb_bufsize);
	}
	sconn->smb1.sessions.done_sesssetup = true;

	END_PROFILE(SMBsesssetupX);
	chain_reply(req);
	return;
}

Project: samba
File: sesssetup.c

static void reply_sesssetup_blob(struct smb_request *req,
				 DATA_BLOB blob,
				 NTSTATUS nt_status)
{
	if (!NT_STATUS_IS_OK(nt_status) &&
	    !NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
		reply_nterror(req, nt_status_squash(nt_status));
		return;
	}

	nt_status = nt_status_squash(nt_status);
	SIVAL(req->outbuf, smb_rcls, NT_STATUS_V(nt_status));
	SSVAL(req->outbuf, smb_vwv0, 0xFF); /* no chaining possible */
	SSVAL(req->outbuf, smb_vwv3, blob.length);

	if ((message_push_blob(&req->outbuf, blob) == -1)
	    || (push_signature(&req->outbuf) == -1)) {
		reply_nterror(req, NT_STATUS_NO_MEMORY);
	}
}

Project: samba
File: sesssetup.c

static void reply_spnego_auth(struct smb_request *req,
			      uint16 vuid,
			      DATA_BLOB blob1,
			      AUTH_NTLMSSP_STATE **auth_ntlmssp_state)
{
	DATA_BLOB auth = data_blob_null;
	DATA_BLOB auth_reply = data_blob_null;
	DATA_BLOB secblob = data_blob_null;
	NTSTATUS status = NT_STATUS_LOGON_FAILURE;
	struct smbd_server_connection *sconn = smbd_server_conn;

	if (!spnego_parse_auth(blob1, &auth)) {
#if 0
		file_save("auth.dat", blob1.data, blob1.length);
#endif
		/* Kill the intermediate vuid */
		invalidate_vuid(sconn, vuid);

		reply_nterror(req, nt_status_squash(
				      NT_STATUS_LOGON_FAILURE));
		return;
	}

	if (auth.data[0] == ASN1_APPLICATION(0)) {
		/* Might be a second negTokenTarg packet */
		char *kerb_mech = NULL;

		status = parse_spnego_mechanisms(auth, &secblob, &kerb_mech);

		if (!NT_STATUS_IS_OK(status)) {
			/* Kill the intermediate vuid */
			invalidate_vuid(sconn, vuid);
			reply_nterror(req, nt_status_squash(status));
			return;
		}

		DEBUG(3,("reply_spnego_auth: Got secblob of size %lu\n",
				(unsigned long)secblob.length));
#ifdef HAVE_KRB5
		if (kerb_mech && ((lp_security()==SEC_ADS) ||
					USE_KERBEROS_KEYTAB)) {
			bool destroy_vuid = True;
			reply_spnego_kerberos(req, &secblob, kerb_mech,
					      vuid, &destroy_vuid);
			data_blob_free(&secblob);
			data_blob_free(&auth);
			if (destroy_vuid) {
				/* Kill the intermediate vuid */
				invalidate_vuid(sconn, vuid);
			}
			SAFE_FREE(kerb_mech);
			return;
		}
#endif
		/* Can't blunder into NTLMSSP auth if we have
		 * a krb5 ticket. */

		if (kerb_mech) {
			/* Kill the intermediate vuid */
			invalidate_vuid(sconn, vuid);
			DEBUG(3,("reply_spnego_auth: network "
				"misconfiguration, client sent us a "
				"krb5 ticket and kerberos security "
				"not enabled\n"));
			reply_nterror(req, nt_status_squash(
					NT_STATUS_LOGON_FAILURE));
			SAFE_FREE(kerb_mech);
		}
	}

	/* If we get here it wasn't a negTokenTarg auth packet. */
	data_blob_free(&secblob);

	if (!*auth_ntlmssp_state) {
		status = auth_ntlmssp_start(auth_ntlmssp_state);
		if (!NT_STATUS_IS_OK(status)) {
			/* Kill the intermediate vuid */
			invalidate_vuid(sconn, vuid);
			reply_nterror(req, nt_status_squash(status));
			return;
		}
	}

	status = auth_ntlmssp_update(*auth_ntlmssp_state,
					auth, &auth_reply);

	data_blob_free(&auth);

	/* Don't send the mechid as we've already sent this (RFC4178). */

	reply_spnego_ntlmssp(req, vuid,
			     auth_ntlmssp_state,
			     &auth_reply, status, NULL, true);

	data_blob_free(&auth_reply);

	/* and tell smbd that we have already replied to this packet */
	return;
}

Project: samba
File: sesssetup.c

static void reply_spnego_kerberos(struct smb_request *req,
				  DATA_BLOB *secblob,
				  const char *mechOID,
				  uint16 vuid,
				  bool *p_invalidate_vuid)
{
	TALLOC_CTX *mem_ctx;
	DATA_BLOB ticket;
	char *client, *p, *domain;
	fstring netbios_domain_name;
	struct passwd *pw;
	fstring user;
	int sess_vuid = req->vuid;
	NTSTATUS ret = NT_STATUS_OK;
	struct PAC_DATA *pac_data = NULL;
	DATA_BLOB ap_rep, ap_rep_wrapped, response;
	auth_serversupplied_info *server_info = NULL;
	DATA_BLOB session_key = data_blob_null;
	uint8 tok_id[2];
	DATA_BLOB nullblob = data_blob_null;
	fstring real_username;
	bool map_domainuser_to_guest = False;
	bool username_was_mapped;
	struct PAC_LOGON_INFO *logon_info = NULL;
	struct smbd_server_connection *sconn = smbd_server_conn;

	ZERO_STRUCT(ticket);
	ZERO_STRUCT(ap_rep);
	ZERO_STRUCT(ap_rep_wrapped);
	ZERO_STRUCT(response);

	/* Normally we will always invalidate the intermediate vuid. */
	*p_invalidate_vuid = True;

	mem_ctx = talloc_init("reply_spnego_kerberos");
	if (mem_ctx == NULL) {
		reply_nterror(req, nt_status_squash(NT_STATUS_NO_MEMORY));
		return;
	}

	if (!spnego_parse_krb5_wrap(*secblob, &ticket, tok_id)) {
		talloc_destroy(mem_ctx);
		reply_nterror(req, nt_status_squash(NT_STATUS_LOGON_FAILURE));
		return;
	}

	ret = ads_verify_ticket(mem_ctx, lp_realm(), 0, &ticket,
				&client, &pac_data, &ap_rep,
				&session_key, True);

	data_blob_free(&ticket);

	if (!NT_STATUS_IS_OK(ret)) {
#if 0
		/* Experiment that failed.
		 * See "only happens with a KDC" comment below. */

		if (NT_STATUS_EQUAL(ret, NT_STATUS_TIME_DIFFERENCE_AT_DC)) {

			/*
			 * Windows in this case returns
			 * NT_STATUS_MORE_PROCESSING_REQUIRED
			 * with a negTokenTarg blob containing an krb5_error
			 * struct ASN1 encoded containing KRB5KRB_AP_ERR_SKEW.
			 * The client then fixes its clock and continues rather
			 * than giving an error. JRA.
			 * -- Looks like this only happens with a KDC. JRA.
			 */

			bool ok = make_krb5_skew_error(&ap_rep);
			if (!ok) {
				talloc_destroy(mem_ctx);
				return ERROR_NT(nt_status_squash(
						NT_STATUS_LOGON_FAILURE));
			}
			ap_rep_wrapped = spnego_gen_krb5_wrap(ap_rep,
					TOK_ID_KRB_ERROR);
			response = spnego_gen_auth_response(&ap_rep_wrapped,
					ret, OID_KERBEROS5_OLD);
			reply_sesssetup_blob(conn, inbuf, outbuf, response,
					NT_STATUS_MORE_PROCESSING_REQUIRED);

			/*
			 * In this one case we don't invalidate the
			 * intermediate vuid as we're expecting the client
			 * to re-use it for the next sessionsetupX packet. JRA.
			 */

			*p_invalidate_vuid = False;

			data_blob_free(&ap_rep);
			data_blob_free(&ap_rep_wrapped);
			data_blob_free(&response);
			talloc_destroy(mem_ctx);
			return -1; /* already replied */
		}
#else
		if (!NT_STATUS_EQUAL(ret, NT_STATUS_TIME_DIFFERENCE_AT_DC)) {
			ret = NT_STATUS_LOGON_FAILURE;
		}
#endif
		DEBUG(1,("Failed to verify incoming ticket with error %s!\n",
				nt_errstr(ret)));
		talloc_destroy(mem_ctx);
		reply_nterror(req, nt_status_squash(ret));
		return;
	}

	DEBUG(3,("Ticket name is [%s]\n", client));

	p = strchr_m(client, '@');
	if (!p) {
		DEBUG(3,("Doesn't look like a valid principal\n"));
		data_blob_free(&ap_rep);
		data_blob_free(&session_key);
		talloc_destroy(mem_ctx);
		reply_nterror(req,nt_status_squash(NT_STATUS_LOGON_FAILURE));
		return;
	}

	*p = 0;

	/* save the PAC data if we have it */

	if (pac_data) {
		logon_info = get_logon_info_from_pac(pac_data);
		if (logon_info) {
			netsamlogon_cache_store( client, &logon_info->info3 );
		}
	}

	if (!strequal(p+1, lp_realm())) {
		DEBUG(3,("Ticket for foreign realm %s@%s\n", client, p+1));
		if (!lp_allow_trusted_domains()) {
			data_blob_free(&ap_rep);
			data_blob_free(&session_key);
			talloc_destroy(mem_ctx);
			reply_nterror(req, nt_status_squash(
					      NT_STATUS_LOGON_FAILURE));
			return;
		}
	}

	/* this gives a fully qualified user name (ie. with full realm).
	   that leads to very long usernames, but what else can we do? */

	domain = p+1;

	if (logon_info && logon_info->info3.base.domain.string) {
		fstrcpy(netbios_domain_name,
			logon_info->info3.base.domain.string);
		domain = netbios_domain_name;
		DEBUG(10, ("Mapped to [%s] (using PAC)\n", domain));

	} else {

		/* If we have winbind running, we can (and must) shorten the
		   username by using the short netbios name. Otherwise we will
		   have inconsistent user names. With Kerberos, we get the
		   fully qualified realm, with ntlmssp we get the short
		   name. And even w2k3 does use ntlmssp if you for example
		   connect to an ip address. */

		wbcErr wbc_status;
		struct wbcDomainInfo *info = NULL;

		DEBUG(10, ("Mapping [%s] to short name\n", domain));

		wbc_status = wbcDomainInfo(domain, &info);

		if (WBC_ERROR_IS_OK(wbc_status)) {

			fstrcpy(netbios_domain_name,
				info->short_name);

			wbcFreeMemory(info);
			domain = netbios_domain_name;
			DEBUG(10, ("Mapped to [%s] (using Winbind)\n", domain));
		} else {
			DEBUG(3, ("Could not find short name: %s\n",
				wbcErrorString(wbc_status)));
		}
	}

	fstr_sprintf(user, "%s%c%s", domain, *lp_winbind_separator(), client);

	/* lookup the passwd struct, create a new user if necessary */

	username_was_mapped = map_username(sconn, user);

	pw = smb_getpwnam( mem_ctx, user, real_username, True );

	if (pw) {
		/* if a real user check pam account restrictions */
		/* only really perfomed if "obey pam restriction" is true */
		/* do this before an eventual mapping to guest occurs */
		ret = smb_pam_accountcheck(pw->pw_name);
		if (  !NT_STATUS_IS_OK(ret)) {
			DEBUG(1,("PAM account restriction "
				"prevents user login\n"));
			data_blob_free(&ap_rep);
			data_blob_free(&session_key);
			TALLOC_FREE(mem_ctx);
			reply_nterror(req, nt_status_squash(ret));
			return;
		}
	}

	if (!pw) {

		/* this was originally the behavior of Samba 2.2, if a user
		   did not have a local uid but has been authenticated, then
		   map them to a guest account */

		if (lp_map_to_guest() == MAP_TO_GUEST_ON_BAD_UID){
			map_domainuser_to_guest = True;
			fstrcpy(user,lp_guestaccount());
			pw = smb_getpwnam( mem_ctx, user, real_username, True );
		}

		/* extra sanity check that the guest account is valid */

		if ( !pw ) {
			DEBUG(1,("Username %s is invalid on this system\n",
				user));
			data_blob_free(&ap_rep);
			data_blob_free(&session_key);
			TALLOC_FREE(mem_ctx);
			reply_nterror(req, nt_status_squash(
					      NT_STATUS_LOGON_FAILURE));
			return;
		}
	}

	/* setup the string used by %U */

	sub_set_smb_name( real_username );
	reload_services(True);

	if ( map_domainuser_to_guest ) {
		make_server_info_guest(NULL, &server_info);
	} else if (logon_info) {
		/* pass the unmapped username here since map_username()
		   will be called again from inside make_server_info_info3() */

		ret = make_server_info_info3(mem_ctx, client, domain,
					     &server_info, &logon_info->info3);
		if ( !NT_STATUS_IS_OK(ret) ) {
			DEBUG(1,("make_server_info_info3 failed: %s!\n",
				 nt_errstr(ret)));
			data_blob_free(&ap_rep);
			data_blob_free(&session_key);
			TALLOC_FREE(mem_ctx);
			reply_nterror(req, nt_status_squash(ret));
			return;
		}

	} else {
		/*
		 * We didn't get a PAC, we have to make up the user
		 * ourselves. Try to ask the pdb backend to provide
		 * SID consistency with ntlmssp session setup
		 */
		struct samu *sampass;

		sampass = samu_new(talloc_tos());
		if (sampass == NULL) {
			ret = NT_STATUS_NO_MEMORY;
			data_blob_free(&ap_rep);
			data_blob_free(&session_key);
			TALLOC_FREE(mem_ctx);
			reply_nterror(req, nt_status_squash(ret));
			return;
		}

		if (pdb_getsampwnam(sampass, real_username)) {
			DEBUG(10, ("found user %s in passdb, calling "
				   "make_server_info_sam\n", real_username));
			ret = make_server_info_sam(&server_info, sampass);
		} else {
			/*
			 * User not in passdb, make it up artificially
			 */
			TALLOC_FREE(sampass);
			DEBUG(10, ("didn't find user %s in passdb, calling "
				   "make_server_info_pw\n", real_username));
			ret = make_server_info_pw(&server_info, real_username,
						  pw);
		}

		if ( !NT_STATUS_IS_OK(ret) ) {
			DEBUG(1,("make_server_info_[sam|pw] failed: %s!\n",
				 nt_errstr(ret)));
			data_blob_free(&ap_rep);
			data_blob_free(&session_key);
			TALLOC_FREE(mem_ctx);
			reply_nterror(req, nt_status_squash(ret));
			return;
		}

	        /* make_server_info_pw does not set the domain. Without this
		 * we end up with the local netbios name in substitutions for
		 * %D. */

		if (server_info->sam_account != NULL) {
			pdb_set_domain(server_info->sam_account,
					domain, PDB_SET);
		}
	}

	server_info->nss_token |= username_was_mapped;

	/* we need to build the token for the user. make_server_info_guest()
	   already does this */

	if ( !server_info->ptok ) {
		ret = create_local_token( server_info );
		if ( !NT_STATUS_IS_OK(ret) ) {
			DEBUG(10,("failed to create local token: %s\n",
				nt_errstr(ret)));
			data_blob_free(&ap_rep);
			data_blob_free(&session_key);
			TALLOC_FREE( mem_ctx );
			TALLOC_FREE( server_info );
			reply_nterror(req, nt_status_squash(ret));
			return;
		}
	}

	if (!is_partial_auth_vuid(sconn, sess_vuid)) {
		sess_vuid = register_initial_vuid(sconn);
	}

	data_blob_free(&server_info->user_session_key);
	server_info->user_session_key = session_key;
	session_key = data_blob_null;

	/* register_existing_vuid keeps the server info */
	/* register_existing_vuid takes ownership of session_key on success,
	 * no need to free after this on success. A better interface would copy
	 * it.... */

	sess_vuid = register_existing_vuid(sconn,
					sess_vuid,
					server_info,
					nullblob,
					client);

	reply_outbuf(req, 4, 0);
	SSVAL(req->outbuf,smb_uid,sess_vuid);

	if (sess_vuid == UID_FIELD_INVALID ) {
		ret = NT_STATUS_LOGON_FAILURE;
	} else {
		/* current_user_info is changed on new vuid */
		reload_services( True );

		SSVAL(req->outbuf, smb_vwv3, 0);

		if (server_info->guest) {
			SSVAL(req->outbuf,smb_vwv2,1);
		}

		SSVAL(req->outbuf, smb_uid, sess_vuid);

		/* Successful logon. Keep this vuid. */
		*p_invalidate_vuid = False;
	}

        /* wrap that up in a nice GSS-API wrapping */
	if (NT_STATUS_IS_OK(ret)) {
		ap_rep_wrapped = spnego_gen_krb5_wrap(ap_rep,
				TOK_ID_KRB_AP_REP);
	} else {
		ap_rep_wrapped = data_blob_null;
	}
	response = spnego_gen_auth_response(&ap_rep_wrapped, ret,
			mechOID);
	reply_sesssetup_blob(req, response, ret);

	data_blob_free(&ap_rep);
	data_blob_free(&ap_rep_wrapped);
	data_blob_free(&response);
	TALLOC_FREE(mem_ctx);
}

Project: samba
File: sesssetup.c

static void reply_spnego_negotiate(struct smb_request *req,
				   uint16 vuid,
				   DATA_BLOB blob1,
				   AUTH_NTLMSSP_STATE **auth_ntlmssp_state)
{
	DATA_BLOB secblob;
	DATA_BLOB chal;
	char *kerb_mech = NULL;
	NTSTATUS status;
	struct smbd_server_connection *sconn = smbd_server_conn;

	status = parse_spnego_mechanisms(blob1, &secblob, &kerb_mech);
	if (!NT_STATUS_IS_OK(status)) {
		/* Kill the intermediate vuid */
		invalidate_vuid(sconn, vuid);
		reply_nterror(req, nt_status_squash(status));
		return;
	}

	DEBUG(3,("reply_spnego_negotiate: Got secblob of size %lu\n",
				(unsigned long)secblob.length));

#ifdef HAVE_KRB5
	if (kerb_mech && ((lp_security()==SEC_ADS) ||
				USE_KERBEROS_KEYTAB) ) {
		bool destroy_vuid = True;
		reply_spnego_kerberos(req, &secblob, kerb_mech,
				      vuid, &destroy_vuid);
		data_blob_free(&secblob);
		if (destroy_vuid) {
			/* Kill the intermediate vuid */
			invalidate_vuid(sconn, vuid);
		}
		SAFE_FREE(kerb_mech);
		return;
	}
#endif

	if (*auth_ntlmssp_state) {
		auth_ntlmssp_end(auth_ntlmssp_state);
	}

	if (kerb_mech) {
		data_blob_free(&secblob);
		/* The mechtoken is a krb5 ticket, but
		 * we need to fall back to NTLM. */
		reply_spnego_downgrade_to_ntlmssp(req, vuid);
		SAFE_FREE(kerb_mech);
		return;
	}

	status = auth_ntlmssp_start(auth_ntlmssp_state);
	if (!NT_STATUS_IS_OK(status)) {
		/* Kill the intermediate vuid */
		invalidate_vuid(sconn, vuid);
		reply_nterror(req, nt_status_squash(status));
		return;
	}

	status = auth_ntlmssp_update(*auth_ntlmssp_state,
					secblob, &chal);

	data_blob_free(&secblob);

	reply_spnego_ntlmssp(req, vuid, auth_ntlmssp_state,
			     &chal, status, OID_NTLMSSP, true);

	data_blob_free(&chal);

	/* already replied */
	return;
}

Project: samba
File: sesssetup.c

static void reply_spnego_ntlmssp(struct smb_request *req,
				 uint16 vuid,
				 AUTH_NTLMSSP_STATE **auth_ntlmssp_state,
				 DATA_BLOB *ntlmssp_blob, NTSTATUS nt_status,
				 const char *OID,
				 bool wrap)
{
	DATA_BLOB response;
	struct auth_serversupplied_info *server_info = NULL;
	struct smbd_server_connection *sconn = smbd_server_conn;

	if (NT_STATUS_IS_OK(nt_status)) {
		server_info = (*auth_ntlmssp_state)->server_info;
	} else {
		nt_status = do_map_to_guest(nt_status,
			    &server_info,
			    (*auth_ntlmssp_state)->ntlmssp_state->user,
			    (*auth_ntlmssp_state)->ntlmssp_state->domain);
	}

	reply_outbuf(req, 4, 0);

	SSVAL(req->outbuf, smb_uid, vuid);

	if (NT_STATUS_IS_OK(nt_status)) {
		DATA_BLOB nullblob = data_blob_null;

		if (!is_partial_auth_vuid(sconn, vuid)) {
			nt_status = NT_STATUS_LOGON_FAILURE;
			goto out;
		}

		data_blob_free(&server_info->user_session_key);
		server_info->user_session_key =
			data_blob_talloc(
			server_info,
			(*auth_ntlmssp_state)->ntlmssp_state->session_key.data,
			(*auth_ntlmssp_state)->ntlmssp_state->session_key.length);

		/* register_existing_vuid keeps the server info */
		if (register_existing_vuid(sconn, vuid,
				server_info, nullblob,
				(*auth_ntlmssp_state)->ntlmssp_state->user) !=
					vuid) {
			nt_status = NT_STATUS_LOGON_FAILURE;
			goto out;
		}

		(*auth_ntlmssp_state)->server_info = NULL;

		/* current_user_info is changed on new vuid */
		reload_services( True );

		SSVAL(req->outbuf, smb_vwv3, 0);

		if (server_info->guest) {
			SSVAL(req->outbuf,smb_vwv2,1);
		}
	}

  out:

	if (wrap) {
		response = spnego_gen_auth_response(ntlmssp_blob,
				nt_status, OID);
	} else {
		response = *ntlmssp_blob;
	}

	reply_sesssetup_blob(req, response, nt_status);
	if (wrap) {
		data_blob_free(&response);
	}

	/* NT_STATUS_MORE_PROCESSING_REQUIRED from our NTLMSSP code tells us,
	   and the other end, that we are not finished yet. */

	if (!NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
		/* NB. This is *NOT* an error case. JRA */
		auth_ntlmssp_end(auth_ntlmssp_state);
		if (!NT_STATUS_IS_OK(nt_status)) {
			/* Kill the intermediate vuid */
			invalidate_vuid(sconn, vuid);
		}
	}
}

Project: samba
File: sesssetup.c

static void setup_new_vc_session(void)
{
	char addr[INET6_ADDRSTRLEN];

	DEBUG(2,("setup_new_vc_session: New VC == 0, if NT4.x "
		"compatible we would close all old resources.\n"));
#if 0
	conn_close_all();
	invalidate_all_vuids();
#endif
	if (lp_reset_on_zero_vc()) {
		connections_forall(shutdown_other_smbds,
			CONST_DISCARD(void *,
			client_addr(get_client_fd(),addr,sizeof(addr))));
	}
}

Project: samba
File: sesssetup.c

static int shutdown_other_smbds(struct db_record *rec,
				const struct connections_key *key,
				const struct connections_data *crec,
				void *private_data)
{
	const char *ip = (const char *)private_data;

	if (!process_exists(crec->pid)) {
		return 0;
	}

	if (procid_is_me(&crec->pid)) {
		return 0;
	}

	if (strcmp(ip, crec->addr) != 0) {
		return 0;
	}

	DEBUG(0,("shutdown_other_smbds: shutting down pid %u "
		 "(IP %s)\n", (unsigned int)procid_to_pid(&crec->pid), ip));

	messaging_send(smbd_messaging_context(), crec->pid, MSG_SHUTDOWN,
		       &data_blob_null);
	return 0;
}