[SCM] Samba Shared Repository - branch master updated - 439086099ad97a49c93102af1e6edafabea64b6f

Volker Lendecke vlendec at samba.org
Mon Oct 6 07:57:06 GMT 2008


The branch, master has been updated
       via  439086099ad97a49c93102af1e6edafabea64b6f (commit)
       via  2f6026248ec9a84f6a263622f1753e98c89eb543 (commit)
       via  f3ba7fc0b973ea66ee57fe0e1be73b3bcefc07fb (commit)
      from  bb4e9d72dd7de46ae4635ff5fbe5427b2a93e7cc (commit)

http://gitweb.samba.org/?p=samba.git;a=shortlog;h=master


- Log -----------------------------------------------------------------
commit 439086099ad97a49c93102af1e6edafabea64b6f
Author: Volker Lendecke <vl at samba.org>
Date:   Mon Sep 22 19:29:05 2008 +0200

    Add netlogond auth method
    
    This authenticates against a local running samba4 using SamLogonEx. We retrieve
    the machine password using samba4's mymachinepwd script and store the schannel
    key for re-use in secrets.tdb.

commit 2f6026248ec9a84f6a263622f1753e98c89eb543
Author: Volker Lendecke <vl at samba.org>
Date:   Mon Sep 22 19:24:59 2008 +0200

    Add dyn_NCALRPCDIR

commit f3ba7fc0b973ea66ee57fe0e1be73b3bcefc07fb
Author: Volker Lendecke <vl at samba.org>
Date:   Mon Sep 22 19:23:21 2008 +0200

    Store a local schannel key in secrets.tdb

-----------------------------------------------------------------------

Summary of changes:
 source3/Makefile.in           |    7 +
 source3/auth/auth_netlogond.c |  321 +++++++++++++++++++++++++++++++++++++++++
 source3/configure.in          |    3 +-
 source3/dynconfig.c           |    1 +
 source3/include/dynconfig.h   |    4 +
 source3/include/proto.h       |    4 +
 source3/include/secrets.h     |    2 +
 source3/m4/check_path.m4      |   19 +++
 source3/passdb/secrets.c      |   25 ++++
 9 files changed, 385 insertions(+), 1 deletions(-)
 create mode 100644 source3/auth/auth_netlogond.c


Changeset truncated at 500 lines:

diff --git a/source3/Makefile.in b/source3/Makefile.in
index 61e946e..eb6a05c 100644
--- a/source3/Makefile.in
+++ b/source3/Makefile.in
@@ -127,6 +127,7 @@ LOGFILEBASE = @logfilebase@
 CONFIGFILE = $(CONFIGDIR)/smb.conf
 LMHOSTSFILE = $(CONFIGDIR)/lmhosts
 CTDBDIR = @ctdbdir@
+NCALRPCDIR = @ncalrpcdir@
 
 # This is where smbpasswd et al go
 PRIVATEDIR = @privatedir@
@@ -166,6 +167,7 @@ PATH_FLAGS = -DSMB_PASSWD_FILE=\"$(SMB_PASSWD_FILE)\" \
 	-DLOGFILEBASE=\"$(LOGFILEBASE)\" \
 	-DSHLIBEXT=\"@SHLIBEXT@\" \
 	-DCTDBDIR=\"$(CTDBDIR)\" \
+	-DNCALRPCDIR=\"$(NCALRPCDIR)\" \
 	-DCONFIGDIR=\"$(CONFIGDIR)\" \
 	-DCODEPAGEDIR=\"$(CODEPAGEDIR)\" \
 	-DCACHEDIR=\"$(CACHEDIR)\" \
@@ -636,6 +638,7 @@ AUTH_SERVER_OBJ = auth/auth_server.o
 AUTH_UNIX_OBJ = auth/auth_unix.o
 AUTH_WINBIND_OBJ = auth/auth_winbind.o
 AUTH_SCRIPT_OBJ = auth/auth_script.o
+AUTH_NETLOGOND_OBJ = auth/auth_netlogond.o
 
 AUTH_OBJ = auth/auth.o @AUTH_STATIC@ auth/auth_util.o auth/token_util.o \
 	   auth/auth_compat.o auth/auth_ntlmssp.o \
@@ -2195,6 +2198,10 @@ bin/script. at SHLIBEXT@: $(BINARY_PREREQS) $(AUTH_SCRIPT_OBJ)
 	@echo "Building plugin $@"
 	@$(SHLD_MODULE) $(AUTH_SCRIPT_OBJ)
 
+bin/netlogond. at SHLIBEXT@: $(BINARY_PREREQS) $(AUTH_NETLOGOND_OBJ)
+	@echo "Building plugin $@"
+	@$(SHLD_MODULE) $(AUTH_NETLOGOND_OBJ)
+
 bin/smbserver. at SHLIBEXT@: $(BINARY_PREREQS) $(AUTH_SERVER_OBJ)
 	@echo "Building plugin $@"
 	@$(SHLD_MODULE) $(AUTH_SERVER_OBJ)
diff --git a/source3/auth/auth_netlogond.c b/source3/auth/auth_netlogond.c
new file mode 100644
index 0000000..a57f3b7
--- /dev/null
+++ b/source3/auth/auth_netlogond.c
@@ -0,0 +1,321 @@
+/*
+   Unix SMB/CIFS implementation.
+   Authenticate against a netlogon pipe listening on a unix domain socket
+   Copyright (C) Volker Lendecke 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"
+
+#undef DBGC_CLASS
+#define DBGC_CLASS DBGC_AUTH
+
+static NTSTATUS netlogond_validate(TALLOC_CTX *mem_ctx,
+				   const struct auth_context *auth_context,
+				   const char *ncalrpc_sockname,
+				   uint8_t schannel_key[16],
+				   const auth_usersupplied_info *user_info,
+				   struct netr_SamInfo3 **pinfo3,
+				   NTSTATUS *schannel_bind_result)
+{
+	struct rpc_pipe_client *p;
+	struct cli_pipe_auth_data *auth;
+	struct netr_SamInfo3 *info3 = NULL;
+	NTSTATUS status;
+
+	*schannel_bind_result = NT_STATUS_OK;
+
+	status = rpc_pipe_open_ncalrpc(talloc_tos(), ncalrpc_sockname,
+				       &ndr_table_netlogon.syntax_id, &p);
+	if (!NT_STATUS_IS_OK(status)) {
+		DEBUG(10, ("rpc_pipe_open_ncalrpc failed: %s\n",
+			   nt_errstr(status)));
+		return status;
+	}
+
+	status = rpccli_schannel_bind_data(p, lp_workgroup(),
+					   PIPE_AUTH_LEVEL_PRIVACY,
+					   schannel_key, &auth);
+	if (!NT_STATUS_IS_OK(status)) {
+		DEBUG(10, ("rpccli_schannel_bind_data failed: %s\n",
+			   nt_errstr(status)));
+		TALLOC_FREE(p);
+		return status;
+	}
+
+	status = rpc_pipe_bind(p, auth);
+	if (!NT_STATUS_IS_OK(status)) {
+		DEBUG(10, ("rpc_pipe_bind failed: %s\n", nt_errstr(status)));
+		TALLOC_FREE(p);
+		*schannel_bind_result = status;
+		return status;
+	}
+
+	/*
+	 * We have to fake a struct dcinfo, so that
+	 * rpccli_netlogon_sam_network_logon_ex can decrypt the session keys.
+	 */
+
+	p->dc = talloc(p, struct dcinfo);
+	if (p->dc == NULL) {
+		DEBUG(0, ("talloc failed\n"));
+		TALLOC_FREE(p);
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	memcpy(p->dc->sess_key, schannel_key, 16);
+
+	status = rpccli_netlogon_sam_network_logon_ex(
+		p, p,
+		user_info->logon_parameters,/* flags such as 'allow
+					     * workstation logon' */
+		global_myname(),            /* server name */
+		user_info->smb_name,        /* user name logging on. */
+		user_info->client_domain,   /* domain name */
+		user_info->wksta_name,      /* workstation name */
+		(uchar *)auth_context->challenge.data, /* 8 byte challenge. */
+		user_info->lm_resp,         /* lanman 24 byte response */
+		user_info->nt_resp,         /* nt 24 byte response */
+		&info3);                    /* info3 out */
+
+	DEBUG(10, ("rpccli_netlogon_sam_network_logon_ex returned %s\n",
+		   nt_errstr(status)));
+
+	if (!NT_STATUS_IS_OK(status)) {
+		TALLOC_FREE(p);
+		return status;
+	}
+
+	*pinfo3 = talloc_move(mem_ctx, &info3);
+
+	TALLOC_FREE(p);
+	return NT_STATUS_OK;
+}
+
+static char *mymachinepw(TALLOC_CTX *mem_ctx)
+{
+	fstring pwd;
+	const char *script;
+	char *to_free = NULL;
+	ssize_t nread;
+	int ret, fd;
+
+	script = lp_parm_const_string(
+		GLOBAL_SECTION_SNUM, "auth_netlogond", "machinepwscript",
+		NULL);
+
+	if (script == NULL) {
+		to_free = talloc_asprintf(talloc_tos(), "%s/%s",
+					  get_dyn_SBINDIR(), "mymachinepw");
+		script = to_free;
+	}
+	if (script == NULL) {
+		return NULL;
+	}
+
+	ret = smbrun(script, &fd);
+	DEBUG(ret ? 0 : 3, ("mymachinepw: Running the command `%s' gave %d\n",
+			    script, ret));
+	TALLOC_FREE(to_free);
+
+	if (ret != 0) {
+		return NULL;
+	}
+
+	pwd[sizeof(pwd)-1] = '\0';
+
+	nread = read(fd, pwd, sizeof(pwd)-1);
+	close(fd);
+
+	if (nread <= 0) {
+		DEBUG(3, ("mymachinepwd: Could not read password\n"));
+		return NULL;
+	}
+
+	DEBUG(0, ("pwd: %d [%s]\n", (int)nread, pwd));
+
+	if (pwd[nread-1] == '\n') {
+		pwd[nread-1] = '\0';
+	}
+
+	return talloc_strdup(mem_ctx, pwd);
+}
+
+static NTSTATUS check_netlogond_security(const struct auth_context *auth_context,
+					 void *my_private_data,
+					 TALLOC_CTX *mem_ctx,
+					 const auth_usersupplied_info *user_info,
+					 auth_serversupplied_info **server_info)
+{
+	TALLOC_CTX *frame = talloc_stackframe();
+	struct netr_SamInfo3 *info3 = NULL;
+	struct rpc_pipe_client *p;
+	struct cli_pipe_auth_data *auth;
+	uint32_t neg_flags = NETLOGON_NEG_AUTH2_ADS_FLAGS;
+	char *plaintext_machinepw;
+	uint8_t machine_password[16];
+	uint8_t schannel_key[16];
+	NTSTATUS schannel_bind_result, status;
+	struct named_mutex *mutex;
+	const char *ncalrpcsock;
+
+	ncalrpcsock = lp_parm_const_string(
+		GLOBAL_SECTION_SNUM, "auth_netlogond", "socket", NULL);
+
+	if (ncalrpcsock == NULL) {
+		ncalrpcsock = talloc_asprintf(talloc_tos(), "%s/%s",
+					      get_dyn_NCALRPCDIR(), "DEFAULT");
+	}
+
+	if (ncalrpcsock == NULL) {
+		status = NT_STATUS_NO_MEMORY;
+		goto done;
+	}
+
+	if (!secrets_fetch_local_schannel_key(schannel_key)) {
+		goto new_key;
+	}
+
+	status = netlogond_validate(talloc_tos(), auth_context, ncalrpcsock,
+				    schannel_key, user_info, &info3,
+				    &schannel_bind_result);
+
+	DEBUG(10, ("netlogond_validate returned %s\n", nt_errstr(status)));
+
+	if (NT_STATUS_IS_OK(status)) {
+		goto okay;
+	}
+
+	if (NT_STATUS_IS_OK(schannel_bind_result)) {
+		/*
+		 * This is a real failure from the DC
+		 */
+		goto done;
+	}
+
+ new_key:
+
+	mutex = grab_named_mutex(talloc_tos(), "LOCAL_SCHANNEL_KEY", 60);
+	if (mutex == NULL) {
+		DEBUG(10, ("Could not get mutex LOCAL_SCHANNEL_KEY\n"));
+		status = NT_STATUS_ACCESS_DENIED;
+		goto done;
+	}
+
+	DEBUG(10, ("schannel bind failed, setting up new key\n"));
+
+	status = rpc_pipe_open_ncalrpc(talloc_tos(), ncalrpcsock,
+				       &ndr_table_netlogon.syntax_id, &p);
+
+	if (!NT_STATUS_IS_OK(status)) {
+		DEBUG(10, ("rpc_pipe_open_ncalrpc failed: %s\n",
+			   nt_errstr(status)));
+		goto done;
+	}
+
+	status = rpccli_anon_bind_data(p, &auth);
+	if (!NT_STATUS_IS_OK(status)) {
+		DEBUG(10, ("rpccli_anon_bind_data failed: %s\n",
+			   nt_errstr(status)));
+		goto done;
+	}
+
+	status = rpc_pipe_bind(p, auth);
+	if (!NT_STATUS_IS_OK(status)) {
+		DEBUG(10, ("rpc_pipe_bind failed: %s\n", nt_errstr(status)));
+		goto done;
+	}
+
+	TALLOC_FREE(auth);
+
+	plaintext_machinepw = mymachinepw(talloc_tos());
+	if (plaintext_machinepw == NULL) {
+		status = NT_STATUS_NO_MEMORY;
+		goto done;
+	}
+
+	E_md4hash(plaintext_machinepw, machine_password);
+
+	TALLOC_FREE(plaintext_machinepw);
+
+	status = rpccli_netlogon_setup_creds(
+		p, global_myname(), lp_workgroup(), global_myname(),
+		global_myname(), machine_password, SEC_CHAN_BDC, &neg_flags);
+
+	if (!NT_STATUS_IS_OK(status)) {
+		DEBUG(10, ("rpccli_netlogon_setup_creds failed: %s\n",
+			   nt_errstr(status)));
+		goto done;
+	}
+
+	memcpy(schannel_key, p->dc->sess_key, 16);
+	secrets_store_local_schannel_key(schannel_key);
+
+	TALLOC_FREE(p);
+
+	/*
+	 * Retry the authentication with the mutex held. This way nobody else
+	 * can step on our toes.
+	 */
+
+	status = netlogond_validate(talloc_tos(), auth_context, ncalrpcsock,
+				    schannel_key, user_info, &info3,
+				    &schannel_bind_result);
+
+	DEBUG(10, ("netlogond_validate returned %s\n", nt_errstr(status)));
+
+	if (!NT_STATUS_IS_OK(status)) {
+		goto done;
+	}
+
+ okay:
+
+	status = make_server_info_info3(mem_ctx, user_info->smb_name,
+					user_info->domain, server_info,
+					info3);
+	if (!NT_STATUS_IS_OK(status)) {
+		DEBUG(10, ("make_server_info_info3 failed: %s\n",
+			   nt_errstr(status)));
+		TALLOC_FREE(frame);
+		return status;
+	}
+
+	status = NT_STATUS_OK;
+
+ done:
+	TALLOC_FREE(frame);
+	return status;
+}
+
+/* module initialisation */
+static NTSTATUS auth_init_netlogond(struct auth_context *auth_context,
+				    const char *param,
+				    auth_methods **auth_method)
+{
+	if (!make_auth_methods(auth_context, auth_method)) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	(*auth_method)->name = "netlogond";
+	(*auth_method)->auth = check_netlogond_security;
+	return NT_STATUS_OK;
+}
+
+NTSTATUS auth_netlogond_init(void)
+{
+	smb_register_auth(AUTH_INTERFACE_VERSION, "netlogond",
+			  auth_init_netlogond);
+	return NT_STATUS_OK;
+}
diff --git a/source3/configure.in b/source3/configure.in
index 545a565..1eba4a0 100644
--- a/source3/configure.in
+++ b/source3/configure.in
@@ -404,7 +404,7 @@ AC_SUBST(DYNEXP)
 
 dnl Add modules that have to be built by default here
 dnl These have to be built static:
-default_static_modules="pdb_smbpasswd pdb_tdbsam rpc_lsarpc rpc_samr rpc_winreg rpc_initshutdown rpc_dssetup rpc_wkssvc rpc_svcctl2 rpc_ntsvcs2 rpc_netlogon rpc_netdfs rpc_srvsvc rpc_spoolss rpc_eventlog2 auth_sam auth_unix auth_winbind auth_server auth_domain auth_builtin vfs_default nss_info_template"
+default_static_modules="pdb_smbpasswd pdb_tdbsam rpc_lsarpc rpc_samr rpc_winreg rpc_initshutdown rpc_dssetup rpc_wkssvc rpc_svcctl2 rpc_ntsvcs2 rpc_netlogon rpc_netdfs rpc_srvsvc rpc_spoolss rpc_eventlog2 auth_sam auth_unix auth_winbind auth_server auth_domain auth_builtin auth_netlogond vfs_default nss_info_template"
 
 dnl These are preferably build shared, and static if dlopen() is not available
 default_shared_modules="vfs_recycle vfs_audit vfs_extd_audit vfs_full_audit vfs_netatalk vfs_fake_perms vfs_default_quota vfs_readonly vfs_cap vfs_expand_msdfs vfs_shadow_copy vfs_shadow_copy2 charset_CP850 charset_CP437 auth_script vfs_readahead vfs_xattr_tdb vfs_streams_xattr vfs_acl_xattr vfs_smb_traffic_analyzer"
@@ -6077,6 +6077,7 @@ SMB_MODULE(auth_server, \$(AUTH_SERVER_OBJ), "bin/smbserver.$SHLIBEXT", AUTH)
 SMB_MODULE(auth_domain, \$(AUTH_DOMAIN_OBJ), "bin/domain.$SHLIBEXT", AUTH)
 SMB_MODULE(auth_builtin, \$(AUTH_BUILTIN_OBJ), "bin/builtin.$SHLIBEXT", AUTH)
 SMB_MODULE(auth_script, \$(AUTH_SCRIPT_OBJ), "bin/script.$SHLIBEXT", AUTH)
+SMB_MODULE(auth_netlogond, \$(AUTH_NETLOGOND_OBJ), "bin/netlogond.$SHLIBEXT", AUTH)
 SMB_SUBSYSTEM(AUTH,auth/auth.o)
 
 SMB_MODULE(vfs_default, \$(VFS_DEFAULT_OBJ), "bin/default.$SHLIBEXT", VFS)
diff --git a/source3/dynconfig.c b/source3/dynconfig.c
index 3a54507..6125f99 100644
--- a/source3/dynconfig.c
+++ b/source3/dynconfig.c
@@ -77,6 +77,7 @@ DEFINE_DYN_CONFIG_PARAM(MODULESDIR)
 DEFINE_DYN_CONFIG_PARAM(SHLIBEXT)
 DEFINE_DYN_CONFIG_PARAM(LOCKDIR)
 DEFINE_DYN_CONFIG_PARAM(PIDDIR)
+DEFINE_DYN_CONFIG_PARAM(NCALRPCDIR)
 DEFINE_DYN_CONFIG_PARAM(SMB_PASSWD_FILE)
 DEFINE_DYN_CONFIG_PARAM(PRIVATE_DIR)
 
diff --git a/source3/include/dynconfig.h b/source3/include/dynconfig.h
index 758bde3..8267064 100644
--- a/source3/include/dynconfig.h
+++ b/source3/include/dynconfig.h
@@ -71,6 +71,10 @@ const char *get_dyn_PIDDIR(void);
 const char *set_dyn_PIDDIR(const char *newpath);
 bool is_default_dyn_PIDDIR(void);
 
+const char *get_dyn_NCALRPCDIR(void);
+const char *set_dyn_NCALRPCDIR(const char *newpath);
+bool is_default_dyn_NCALRPCDIR(void);
+
 const char *get_dyn_SMB_PASSWD_FILE(void);
 const char *set_dyn_SMB_PASSWD_FILE(const char *newpath);
 bool is_default_dyn_SMB_PASSWD_FILE(void);
diff --git a/source3/include/proto.h b/source3/include/proto.h
index 7cdcba1..30e309c 100644
--- a/source3/include/proto.h
+++ b/source3/include/proto.h
@@ -46,6 +46,8 @@ bool password_ok(const char *smb_name, DATA_BLOB password_blob);
 void attempt_machine_password_change(void);
 NTSTATUS auth_domain_init(void);
 
+NTSTATUS auth_netlogond_init(void);
+
 /* The following definitions come from auth/auth_ntlmssp.c  */
 
 NTSTATUS auth_ntlmssp_start(AUTH_NTLMSSP_STATE **auth_ntlmssp_state);
@@ -6421,6 +6423,8 @@ bool secrets_restore_schannel_session_info(TALLOC_CTX *mem_ctx,
 				struct dcinfo **ppdc);
 bool secrets_store_generic(const char *owner, const char *key, const char *secret);
 char *secrets_fetch_generic(const char *owner, const char *key);
+bool secrets_store_local_schannel_key(uint8_t schannel_key[16]);
+bool secrets_fetch_local_schannel_key(uint8_t schannel_key[16]);
 
 /* The following definitions come from passdb/util_builtin.c  */
 
diff --git a/source3/include/secrets.h b/source3/include/secrets.h
index d9f4575..3c8e2cc 100644
--- a/source3/include/secrets.h
+++ b/source3/include/secrets.h
@@ -45,6 +45,8 @@
 
 #define SECRETS_LDAP_BIND_PW "SECRETS/LDAP_BIND_PW"
 
+#define SECRETS_LOCAL_SCHANNEL_KEY "SECRETS/LOCAL_SCHANNEL_KEY"
+
 /* Authenticated user info is stored in secrets.tdb under these keys */
 
 #define SECRETS_AUTH_USER      "SECRETS/AUTH_USER"
diff --git a/source3/m4/check_path.m4 b/source3/m4/check_path.m4
index 7aa8c21..40a97d3 100644
--- a/source3/m4/check_path.m4
+++ b/source3/m4/check_path.m4
@@ -18,6 +18,7 @@ AC_PREFIX_DEFAULT(/usr/local/samba)
 rootsbindir="\${SBINDIR}"
 lockdir="\${VARDIR}/locks"
 piddir="\${VARDIR}/locks"
+ncalrpcdir="\${VARDIR}/ncalrpc"
 test "${mandir}" || mandir="\${prefix}/man"
 logfilebase="\${VARDIR}"
 privatedir="\${prefix}/private"
@@ -46,6 +47,7 @@ AC_ARG_WITH(fhs,
     codepagedir="\${MODULESDIR}"
     statedir="\${VARDIR}/lib/samba"
     cachedir="\${VARDIR}/lib/samba"
+    ncalrpcdir="\${VARDIR}/ncalrpc"
     AC_DEFINE(FHS_COMPATIBLE, 1, [Whether to use fully FHS-compatible paths])
     ;;
   esac])
@@ -115,6 +117,22 @@ AC_ARG_WITH(piddir,
   esac])
 
 #################################################
+# set ncalrpc directory location
+AC_ARG_WITH(ncalprcdir,
+[AS_HELP_STRING([--with-ncalprcdir=DIR], [Where to put ncalrpc sockets ($ac_default_prefix/var/ncalrpc)])],
+[ case "$withval" in
+  yes|no)
+  #
+  # Just in case anybody calls it without argument
+  #
+    AC_MSG_WARN([--with-ncalrpcdir called without argument - will use default])
+  ;;
+  * )
+    ncalrpcdir="$withval"
+    ;;
+  esac])
+
+#################################################
 # set SWAT directory location
 AC_ARG_WITH(swatdir,
 [AS_HELP_STRING([--with-swatdir=DIR], [Where to put SWAT files ($ac_default_prefix/swat)])],
@@ -227,6 +245,7 @@ AC_ARG_WITH(mandir,
 AC_SUBST(configdir)
 AC_SUBST(lockdir)
 AC_SUBST(piddir)
+AC_SUBST(ncalrpcdir)
 AC_SUBST(logfilebase)
 AC_SUBST(ctdbdir)
 AC_SUBST(privatedir)


-- 
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