6 files changed, 236 insertions, 0 deletions
diff --git a/lib/uid_wrapper/config.m4 b/lib/uid_wrapper/config.m4
new file mode 100644
index 0000000000..db6537bf95
--- /dev/null
+++ b/lib/uid_wrapper/config.m4
@@ -0,0 +1,16 @@
+AC_ARG_ENABLE(uid-wrapper,
+AS_HELP_STRING([--enable-uid-wrapper], [Turn on uid wrapper library (default=no)]))
+
+HAVE_UID_WRAPPER=no
+
+if eval "test x$developer = xyes"; then
+	enable_uid_wrapper=yes
+fi
+
+if eval "test x$enable_uid_wrapper = xyes"; then
+        AC_DEFINE(UID_WRAPPER,1,[Use uid wrapper library])
+	HAVE_UID_WRAPPER=yes
+fi
+
+AC_SUBST(HAVE_UID_WRAPPER)
+AC_SUBST(UID_WRAPPER_OBJS)
diff --git a/lib/uid_wrapper/config.mk b/lib/uid_wrapper/config.mk
new file mode 100644
index 0000000000..1bebc68118
--- /dev/null
+++ b/lib/uid_wrapper/config.mk
@@ -0,0 +1,9 @@
+##############################
+# Start SUBSYSTEM UID_WRAPPER
+[SUBSYSTEM::UID_WRAPPER]
+PRIVATE_DEPENDENCIES = LIBTALLOC
+# End SUBSYSTEM UID_WRAPPER
+##############################
+
+UID_WRAPPER_OBJ_FILES = $(uidwrappersrcdir)/uid_wrapper.o
+
diff --git a/lib/uid_wrapper/uid_wrapper.c b/lib/uid_wrapper/uid_wrapper.c
new file mode 100644
index 0000000000..e009fa0b5c
--- /dev/null
+++ b/lib/uid_wrapper/uid_wrapper.c
@@ -0,0 +1,147 @@
+/*
+   Copyright (C) Andrew Tridgell 2009
+ 
+   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/>.
+ */
+
+#define UID_WRAPPER_NOT_REPLACE
+#include "includes.h"
+#include "system/passwd.h"
+#include "system/filesys.h"
+
+#ifndef _PUBLIC_
+#define _PUBLIC_
+#endif
+
+/*
+  we keep the virtualised euid/egid/groups information here
+ */
+static struct {
+	bool initialised;
+	bool enabled;
+	uid_t euid;
+	gid_t egid;
+	unsigned ngroups;
+	gid_t *groups;
+} uwrap;
+
+static void uwrap_init(void)
+{
+	if (uwrap.initialised) return;
+	uwrap.initialised = true;
+	if (getenv("UID_WRAPPER")) {
+		uwrap.enabled = true;
+	}
+}
+
+_PUBLIC_ int uwrap_seteuid(uid_t euid)
+{
+	uwrap_init();
+	if (!uwrap.enabled) {
+		return seteuid(euid);
+	}
+	/* assume for now that the ruid stays as root */
+	uwrap.euid = euid;
+	return 0;
+}
+
+_PUBLIC_ uid_t uwrap_geteuid(void)
+{
+	uwrap_init();
+	if (!uwrap.enabled) {
+		return geteuid();
+	}
+	return uwrap.euid;
+}
+
+_PUBLIC_ int uwrap_setegid(gid_t egid)
+{
+	uwrap_init();
+	if (!uwrap.enabled) {
+		return setegid(egid);
+	}
+	/* assume for now that the ruid stays as root */
+	uwrap.egid = egid;
+	return 0;
+}
+
+_PUBLIC_ uid_t uwrap_getegid(void)
+{
+	uwrap_init();
+	if (!uwrap.enabled) {
+		return getegid();
+	}
+	return uwrap.egid;
+}
+
+_PUBLIC_ int uwrap_setgroups(size_t size, const gid_t *list)
+{
+	uwrap_init();
+	if (!uwrap.enabled) {
+		return setgroups(size, list);
+	}
+
+	talloc_free(uwrap.groups);
+	uwrap.ngroups = 0;
+
+	uwrap.groups = talloc_array(talloc_autofree_context(), gid_t, size);
+	if (uwrap.groups == NULL) {
+		errno = ENOMEM;
+		return -1;
+	}
+	memcpy(uwrap.groups, list, size*sizeof(gid_t));
+	uwrap.ngroups = size;
+	return 0;
+}
+
+_PUBLIC_ int uwrap_getgroups(int size, gid_t *list)
+{
+	uwrap_init();
+	if (!uwrap.enabled) {
+		return getgroups(size, list);
+	}
+
+	if (size > uwrap.ngroups) {
+		size = uwrap.ngroups;
+	}
+	if (size == 0) {
+		return uwrap.ngroups;
+	}
+	if (size < uwrap.ngroups) {
+		errno = EINVAL;
+		return -1;
+	}
+	memcpy(list, uwrap.groups, size*sizeof(gid_t));
+	return 0;
+}
+
+_PUBLIC_ uid_t uwrap_getuid(void)
+{
+	uwrap_init();
+	if (!uwrap.enabled) {
+		return getuid();
+	}
+	/* we don't simulate ruid changing */
+	return 0;
+}
+
+_PUBLIC_ gid_t uwrap_getgid(void)
+{
+	uwrap_init();
+	if (!uwrap.enabled) {
+		return getgid();
+	}
+	/* we don't simulate rgid changing */
+	return 0;
+}
diff --git a/lib/uid_wrapper/uid_wrapper.h b/lib/uid_wrapper/uid_wrapper.h
new file mode 100644
index 0000000000..e2df613f50
--- /dev/null
+++ b/lib/uid_wrapper/uid_wrapper.h
@@ -0,0 +1,61 @@
+/*
+   Copyright (C) Andrew Tridgell 2009
+ 
+   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/>.
+ */
+
+#ifndef __UID_WRAPPER_H__
+#define __UID_WRAPPER_H__
+
+#ifdef seteuid
+#undef seteuid
+#endif
+#define seteuid	uwrap_seteuid
+
+#ifdef setegid
+#undef setegid
+#endif
+#define setegid	uwrap_setegid
+
+#ifdef geteuid
+#undef geteuid
+#endif
+#define geteuid	uwrap_geteuid
+
+#ifdef getegid
+#undef getegid
+#endif
+#define getegid	uwrap_getegid
+
+#ifdef setgroups
+#undef setgroups
+#endif
+#define setgroups uwrap_setgroups
+
+#ifdef getgroups
+#undef getgroups
+#endif
+#define getgroups uwrap_getgroups
+
+#ifdef getuid
+#undef getuid
+#endif
+#define getuid	uwrap_getuid
+
+#ifdef getgid
+#undef getgid
+#endif
+#define getgid	uwrap_getgid
+
+#endif /* __UID_WRAPPER_H__ */
diff --git a/lib/util/config.mk b/lib/util/config.mk
index ad39096c56..47e026865e 100644
--- a/lib/util/config.mk
+++ b/lib/util/config.mk
@@ -54,6 +54,7 @@ PUBLIC_HEADERS += $(addprefix $(libutilsrcdir)/, util.h \
 ASN1_UTIL_OBJ_FILES = $(libutilsrcdir)/asn1.o
 
 [SUBSYSTEM::UNIX_PRIVS]
+PRIVATE_DEPENDENCIES = UID_WRAPPER
 
 UNIX_PRIVS_OBJ_FILES = $(libutilsrcdir)/unix_privs.o
 
diff --git a/lib/util/util.c b/lib/util/util.c
index f49d25865c..dea140148f 100644
--- a/lib/util/util.c
+++ b/lib/util/util.c
@@ -135,10 +135,12 @@ _PUBLIC_ bool directory_create_or_exist(const char *dname, uid_t uid,
 		}
 		if ((st.st_uid != uid) || 
 		    ((st.st_mode & 0777) != dir_perms)) {
+#ifndef UID_WRAPPER_REPLACE
 			DEBUG(0, ("invalid permissions on directory "
 				  "%s\n", dname));
 			umask(old_umask);
 			return false;
+#endif
 		}
 	}
 	return true;