1 files changed, 563 insertions, 0 deletions
diff --git a/source3/libads/authdata.c b/source3/libads/authdata.c
new file mode 100644
index 0000000000..0bde3e6984
--- /dev/null
+++ b/source3/libads/authdata.c
@@ -0,0 +1,563 @@
+/*
+   Unix SMB/CIFS implementation.
+   kerberos authorization data (PAC) utility library
+   Copyright (C) Jim McDonough <jmcd@us.ibm.com> 2003
+   Copyright (C) Andrew Bartlett <abartlet@samba.org> 2004-2005
+   Copyright (C) Andrew Tridgell 2001
+   Copyright (C) Luke Howard 2002-2003
+   Copyright (C) Stefan Metzmacher 2004-2005
+   Copyright (C) Guenther Deschner 2005,2007,2008
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "includes.h"
+
+#ifdef HAVE_KRB5
+
+/****************************************************************
+****************************************************************/
+
+static krb5_error_code check_pac_checksum(TALLOC_CTX *mem_ctx,
+					  DATA_BLOB pac_data,
+					  struct PAC_SIGNATURE_DATA *sig,
+					  krb5_context context,
+					  krb5_keyblock *keyblock)
+{
+	krb5_error_code ret;
+	krb5_checksum cksum;
+	krb5_keyusage usage = 0;
+
+	smb_krb5_checksum_from_pac_sig(&cksum, sig);
+
+#ifdef HAVE_KRB5_KU_OTHER_CKSUM /* Heimdal */
+	usage = KRB5_KU_OTHER_CKSUM;
+#elif defined(HAVE_KRB5_KEYUSAGE_APP_DATA_CKSUM) /* MIT */
+	usage = KRB5_KEYUSAGE_APP_DATA_CKSUM;
+#else
+#error UNKNOWN_KRB5_KEYUSAGE
+#endif
+
+	ret = smb_krb5_verify_checksum(context,
+				       keyblock,
+				       usage,
+				       &cksum,
+				       pac_data.data,
+				       pac_data.length);
+
+	if (ret) {
+		DEBUG(2,("check_pac_checksum: PAC Verification failed: %s (%d)\n",
+			error_message(ret), ret));
+		return ret;
+	}
+
+	return ret;
+}
+
+/****************************************************************
+****************************************************************/
+
+ NTSTATUS decode_pac_data(TALLOC_CTX *mem_ctx,
+			 DATA_BLOB *pac_data_blob,
+			 krb5_context context,
+			 krb5_keyblock *service_keyblock,
+			 krb5_const_principal client_principal,
+			 time_t tgs_authtime,
+			 struct PAC_DATA **pac_data_out)
+{
+	NTSTATUS status;
+	enum ndr_err_code ndr_err;
+	krb5_error_code ret;
+	DATA_BLOB modified_pac_blob;
+
+	NTTIME tgs_authtime_nttime;
+	krb5_principal client_principal_pac = NULL;
+	int i;
+
+	struct PAC_SIGNATURE_DATA *srv_sig_ptr = NULL;
+	struct PAC_SIGNATURE_DATA *kdc_sig_ptr = NULL;
+	struct PAC_SIGNATURE_DATA *srv_sig_wipe = NULL;
+	struct PAC_SIGNATURE_DATA *kdc_sig_wipe = NULL;
+	struct PAC_LOGON_NAME *logon_name = NULL;
+	struct PAC_LOGON_INFO *logon_info = NULL;
+	struct PAC_DATA *pac_data = NULL;
+	struct PAC_DATA_RAW *pac_data_raw = NULL;
+
+	DATA_BLOB *srv_sig_blob = NULL;
+	DATA_BLOB *kdc_sig_blob = NULL;
+
+	*pac_data_out = NULL;
+
+	pac_data = TALLOC_ZERO_P(mem_ctx, struct PAC_DATA);
+	pac_data_raw = TALLOC_ZERO_P(mem_ctx, struct PAC_DATA_RAW);
+	kdc_sig_wipe = TALLOC_ZERO_P(mem_ctx, struct PAC_SIGNATURE_DATA);
+	srv_sig_wipe = TALLOC_ZERO_P(mem_ctx, struct PAC_SIGNATURE_DATA);
+	if (!pac_data_raw || !pac_data || !kdc_sig_wipe || !srv_sig_wipe) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	ndr_err = ndr_pull_struct_blob(pac_data_blob, pac_data,
+			pac_data,
+		       (ndr_pull_flags_fn_t)ndr_pull_PAC_DATA);
+	if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
+		status = ndr_map_error2ntstatus(ndr_err);
+		DEBUG(0,("can't parse the PAC: %s\n",
+			nt_errstr(status)));
+		return status;
+	}
+
+	if (pac_data->num_buffers < 4) {
+		/* we need logon_ingo, service_key and kdc_key */
+		DEBUG(0,("less than 4 PAC buffers\n"));
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+
+	ndr_err = ndr_pull_struct_blob(pac_data_blob, pac_data_raw,
+				       pac_data_raw,
+				       (ndr_pull_flags_fn_t)ndr_pull_PAC_DATA_RAW);
+	if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
+		status = ndr_map_error2ntstatus(ndr_err);
+		DEBUG(0,("can't parse the PAC: %s\n",
+			nt_errstr(status)));
+		return status;
+	}
+
+	if (pac_data_raw->num_buffers < 4) {
+		/* we need logon_ingo, service_key and kdc_key */
+		DEBUG(0,("less than 4 PAC buffers\n"));
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+
+	if (pac_data->num_buffers != pac_data_raw->num_buffers) {
+		/* we need logon_ingo, service_key and kdc_key */
+		DEBUG(0,("misparse!  PAC_DATA has %d buffers while PAC_DATA_RAW has %d\n",
+			 pac_data->num_buffers, pac_data_raw->num_buffers));
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+
+	for (i=0; i < pac_data->num_buffers; i++) {
+		if (pac_data->buffers[i].type != pac_data_raw->buffers[i].type) {
+			DEBUG(0,("misparse!  PAC_DATA buffer %d has type %d while PAC_DATA_RAW has %d\n",
+				 i, pac_data->buffers[i].type, pac_data->buffers[i].type));
+			return NT_STATUS_INVALID_PARAMETER;
+		}
+		switch (pac_data->buffers[i].type) {
+			case PAC_TYPE_LOGON_INFO:
+				if (!pac_data->buffers[i].info) {
+					break;
+				}
+				logon_info = pac_data->buffers[i].info->logon_info.info;
+				break;
+			case PAC_TYPE_SRV_CHECKSUM:
+				if (!pac_data->buffers[i].info) {
+					break;
+				}
+				srv_sig_ptr = &pac_data->buffers[i].info->srv_cksum;
+				srv_sig_blob = &pac_data_raw->buffers[i].info->remaining;
+				break;
+			case PAC_TYPE_KDC_CHECKSUM:
+				if (!pac_data->buffers[i].info) {
+					break;
+				}
+				kdc_sig_ptr = &pac_data->buffers[i].info->kdc_cksum;
+				kdc_sig_blob = &pac_data_raw->buffers[i].info->remaining;
+				break;
+			case PAC_TYPE_LOGON_NAME:
+				logon_name = &pac_data->buffers[i].info->logon_name;
+				break;
+			default:
+				break;
+		}
+	}
+
+	if (!logon_info) {
+		DEBUG(0,("PAC no logon_info\n"));
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+
+	if (!logon_name) {
+		DEBUG(0,("PAC no logon_name\n"));
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+
+	if (!srv_sig_ptr || !srv_sig_blob) {
+		DEBUG(0,("PAC no srv_key\n"));
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+
+	if (!kdc_sig_ptr || !kdc_sig_blob) {
+		DEBUG(0,("PAC no kdc_key\n"));
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+
+	/* Find and zero out the signatures, as required by the signing algorithm */
+
+	/* We find the data blobs above, now we parse them to get at the exact portion we should zero */
+	ndr_err = ndr_pull_struct_blob(kdc_sig_blob, kdc_sig_wipe,
+				       kdc_sig_wipe,
+				       (ndr_pull_flags_fn_t)ndr_pull_PAC_SIGNATURE_DATA);
+	if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
+		status = ndr_map_error2ntstatus(ndr_err);
+		DEBUG(0,("can't parse the KDC signature: %s\n",
+			nt_errstr(status)));
+		return status;
+	}
+
+	ndr_err = ndr_pull_struct_blob(srv_sig_blob, srv_sig_wipe,
+				       srv_sig_wipe,
+				       (ndr_pull_flags_fn_t)ndr_pull_PAC_SIGNATURE_DATA);
+	if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
+		status = ndr_map_error2ntstatus(ndr_err);
+		DEBUG(0,("can't parse the SRV signature: %s\n",
+			nt_errstr(status)));
+		return status;
+	}
+
+	/* Now zero the decoded structure */
+	memset(kdc_sig_wipe->signature.data, '\0', kdc_sig_wipe->signature.length);
+	memset(srv_sig_wipe->signature.data, '\0', srv_sig_wipe->signature.length);
+
+	/* and reencode, back into the same place it came from */
+	ndr_err = ndr_push_struct_blob(kdc_sig_blob, pac_data_raw,
+				       kdc_sig_wipe,
+				       (ndr_push_flags_fn_t)ndr_push_PAC_SIGNATURE_DATA);
+	if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
+		status = ndr_map_error2ntstatus(ndr_err);
+		DEBUG(0,("can't repack the KDC signature: %s\n",
+			nt_errstr(status)));
+		return status;
+	}
+	ndr_err = ndr_push_struct_blob(srv_sig_blob, pac_data_raw,
+				       srv_sig_wipe,
+				       (ndr_push_flags_fn_t)ndr_push_PAC_SIGNATURE_DATA);
+	if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
+		status = ndr_map_error2ntstatus(ndr_err);
+		DEBUG(0,("can't repack the SRV signature: %s\n",
+			nt_errstr(status)));
+		return status;
+	}
+
+	/* push out the whole structure, but now with zero'ed signatures */
+	ndr_err = ndr_push_struct_blob(&modified_pac_blob, pac_data_raw,
+				       pac_data_raw,
+				       (ndr_push_flags_fn_t)ndr_push_PAC_DATA_RAW);
+	if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
+		status = ndr_map_error2ntstatus(ndr_err);
+		DEBUG(0,("can't repack the RAW PAC: %s\n",
+			nt_errstr(status)));
+		return status;
+	}
+
+	/* verify by service_key */
+	ret = check_pac_checksum(mem_ctx,
+				 modified_pac_blob, srv_sig_ptr,
+				 context,
+				 service_keyblock);
+	if (ret) {
+		DEBUG(1, ("PAC Decode: Failed to verify the service signature: %s\n",
+			  error_message(ret)));
+		return NT_STATUS_ACCESS_DENIED;
+	}
+
+	/* Convert to NT time, so as not to loose accuracy in comparison */
+	unix_to_nt_time(&tgs_authtime_nttime, tgs_authtime);
+
+	if (tgs_authtime_nttime != logon_name->logon_time) {
+		DEBUG(2, ("PAC Decode: Logon time mismatch between ticket and PAC!\n"));
+		DEBUG(2, ("PAC Decode: PAC: %s\n", nt_time_string(mem_ctx, logon_name->logon_time)));
+		DEBUG(2, ("PAC Decode: Ticket: %s\n", nt_time_string(mem_ctx, tgs_authtime_nttime)));
+		return NT_STATUS_ACCESS_DENIED;
+	}
+
+	ret = smb_krb5_parse_name_norealm(context, logon_name->account_name,
+				    &client_principal_pac);
+	if (ret) {
+		DEBUG(2, ("Could not parse name from incoming PAC: [%s]: %s\n",
+			  logon_name->account_name,
+			  error_message(ret)));
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+
+	if (!smb_krb5_principal_compare_any_realm(context, client_principal, client_principal_pac)) {
+		DEBUG(2, ("Name in PAC [%s] does not match principal name in ticket\n",
+			  logon_name->account_name));
+		krb5_free_principal(context, client_principal_pac);
+		return NT_STATUS_ACCESS_DENIED;
+	}
+
+	DEBUG(3,("Found account name from PAC: %s [%s]\n",
+		 logon_info->info3.base.account_name.string,
+		 logon_info->info3.base.full_name.string));
+
+	DEBUG(10,("Successfully validated Kerberos PAC\n"));
+
+	if (DEBUGLEVEL >= 10) {
+		const char *s;
+		s = NDR_PRINT_STRUCT_STRING(mem_ctx, PAC_DATA, pac_data);
+		if (s) {
+			DEBUGADD(10,("%s\n", s));
+		}
+	}
+
+	*pac_data_out = pac_data;
+
+	return NT_STATUS_OK;
+}
+
+/****************************************************************
+****************************************************************/
+
+struct PAC_LOGON_INFO *get_logon_info_from_pac(struct PAC_DATA *pac_data)
+{
+	int i;
+
+	for (i=0; i < pac_data->num_buffers; i++) {
+
+		if (pac_data->buffers[i].type != PAC_TYPE_LOGON_INFO) {
+			continue;
+		}
+
+		return pac_data->buffers[i].info->logon_info.info;
+	}
+
+	return NULL;
+}
+
+/****************************************************************
+****************************************************************/
+
+NTSTATUS kerberos_return_pac(TALLOC_CTX *mem_ctx,
+			     const char *name,
+			     const char *pass,
+			     time_t time_offset,
+			     time_t *expire_time,
+			     time_t *renew_till_time,
+			     const char *cache_name,
+			     bool request_pac,
+			     bool add_netbios_addr,
+			     time_t renewable_time,
+			     struct PAC_DATA **pac_ret)
+{
+	krb5_error_code ret;
+	NTSTATUS status = NT_STATUS_INVALID_PARAMETER;
+	DATA_BLOB tkt, ap_rep, sesskey1, sesskey2;
+	struct PAC_DATA *pac_data = NULL;
+	char *client_princ_out = NULL;
+	const char *auth_princ = NULL;
+	const char *local_service = NULL;
+	const char *cc = "MEMORY:kerberos_return_pac";
+
+	ZERO_STRUCT(tkt);
+	ZERO_STRUCT(ap_rep);
+	ZERO_STRUCT(sesskey1);
+	ZERO_STRUCT(sesskey2);
+
+	if (!name || !pass) {
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+
+	if (cache_name) {
+		cc = cache_name;
+	}
+
+	if (!strchr_m(name, '@')) {
+		auth_princ = talloc_asprintf(mem_ctx, "%s@%s", name,
+			lp_realm());
+	} else {
+		auth_princ = name;
+	}
+	NT_STATUS_HAVE_NO_MEMORY(auth_princ);
+
+	local_service = talloc_asprintf(mem_ctx, "%s$@%s",
+					global_myname(), lp_realm());
+	NT_STATUS_HAVE_NO_MEMORY(local_service);
+
+	ret = kerberos_kinit_password_ext(auth_princ,
+					  pass,
+					  time_offset,
+					  expire_time,
+					  renew_till_time,
+					  cc,
+					  request_pac,
+					  add_netbios_addr,
+					  renewable_time,
+					  &status);
+	if (ret) {
+		DEBUG(1,("kinit failed for '%s' with: %s (%d)\n",
+			auth_princ, error_message(ret), ret));
+		/* status already set */
+		goto out;
+	}
+
+	DEBUG(10,("got TGT for %s in %s\n", auth_princ, cc));
+	if (expire_time) {
+		DEBUGADD(10,("\tvalid until: %s (%d)\n",
+			http_timestring(*expire_time),
+			(int)*expire_time));
+	}
+	if (renew_till_time) {
+		DEBUGADD(10,("\trenewable till: %s (%d)\n",
+			http_timestring(*renew_till_time),
+			(int)*renew_till_time));
+	}
+
+	/* we cannot continue with krb5 when UF_DONT_REQUIRE_PREAUTH is set,
+	 * in that case fallback to NTLM - gd */
+
+	if (expire_time && renew_till_time &&
+	    (*expire_time == 0) && (*renew_till_time == 0)) {
+		return NT_STATUS_INVALID_LOGON_TYPE;
+	}
+
+
+	ret = cli_krb5_get_ticket(local_service,
+				  time_offset,
+				  &tkt,
+				  &sesskey1,
+				  0,
+				  cc,
+				  NULL);
+	if (ret) {
+		DEBUG(1,("failed to get ticket for %s: %s\n",
+			local_service, error_message(ret)));
+		status = krb5_to_nt_status(ret);
+		goto out;
+	}
+
+	status = ads_verify_ticket(mem_ctx,
+				   lp_realm(),
+				   time_offset,
+				   &tkt,
+				   &client_princ_out,
+				   &pac_data,
+				   &ap_rep,
+				   &sesskey2,
+				   False);
+	if (!NT_STATUS_IS_OK(status)) {
+		DEBUG(1,("ads_verify_ticket failed: %s\n",
+			nt_errstr(status)));
+		goto out;
+	}
+
+	if (!pac_data) {
+		DEBUG(1,("no PAC\n"));
+		status = NT_STATUS_INVALID_PARAMETER;
+		goto out;
+	}
+
+	*pac_ret = pac_data;
+
+out:
+	if (cc != cache_name) {
+		ads_kdestroy(cc);
+	}
+
+	data_blob_free(&tkt);
+	data_blob_free(&ap_rep);
+	data_blob_free(&sesskey1);
+	data_blob_free(&sesskey2);
+
+	SAFE_FREE(client_princ_out);
+
+	return status;
+}
+
+/****************************************************************
+****************************************************************/
+
+static NTSTATUS kerberos_return_pac_logon_info(TALLOC_CTX *mem_ctx,
+					       const char *name,
+					       const char *pass,
+					       time_t time_offset,
+					       time_t *expire_time,
+					       time_t *renew_till_time,
+					       const char *cache_name,
+					       bool request_pac,
+					       bool add_netbios_addr,
+					       time_t renewable_time,
+					       struct PAC_LOGON_INFO **logon_info)
+{
+	NTSTATUS status;
+	struct PAC_DATA *pac_data = NULL;
+	struct PAC_LOGON_INFO *info = NULL;
+
+	status = kerberos_return_pac(mem_ctx,
+				     name,
+				     pass,
+				     time_offset,
+				     expire_time,
+				     renew_till_time,
+				     cache_name,
+				     request_pac,
+				     add_netbios_addr,
+				     renewable_time,
+				     &pac_data);
+	if (!NT_STATUS_IS_OK(status)) {
+		return status;
+	}
+
+	if (!pac_data) {
+		DEBUG(3,("no pac\n"));
+		return NT_STATUS_INVALID_USER_BUFFER;
+	}
+
+	info = get_logon_info_from_pac(pac_data);
+	if (!info) {
+		DEBUG(1,("no logon_info\n"));
+		return NT_STATUS_INVALID_USER_BUFFER;
+	}
+
+	*logon_info = info;
+
+	return NT_STATUS_OK;
+}
+
+/****************************************************************
+****************************************************************/
+
+NTSTATUS kerberos_return_info3_from_pac(TALLOC_CTX *mem_ctx,
+					const char *name,
+					const char *pass,
+					time_t time_offset,
+					time_t *expire_time,
+					time_t *renew_till_time,
+					const char *cache_name,
+					bool request_pac,
+					bool add_netbios_addr,
+					time_t renewable_time,
+					struct netr_SamInfo3 **info3)
+{
+	NTSTATUS status;
+	struct PAC_LOGON_INFO *logon_info = NULL;
+
+	status = kerberos_return_pac_logon_info(mem_ctx,
+						name,
+						pass,
+						time_offset,
+						expire_time,
+						renew_till_time,
+						cache_name,
+						request_pac,
+						add_netbios_addr,
+						renewable_time,
+						&logon_info);
+	if (!NT_STATUS_IS_OK(status)) {
+		return status;
+	}
+
+	*info3 = &logon_info->info3;
+
+	return NT_STATUS_OK;
+}
+#endif