From fd43e0ee09e3f82093e9a15dd6cbd2fbaa113426 Mon Sep 17 00:00:00 2001 From: Andrew Tridgell Date: Wed, 5 Aug 2009 10:50:03 +1000 Subject: [PATCH] added a uid_wrapper library This library intercepts seteuid and related calls, and simulates them in a manner similar to the nss_wrapper and socket_wrapper libraries. This allows us to enable the vfs_unixuid NTVFS module in the build farm, which means we are more likely to catch errors in the token manipulation. The simulation is not complete, but it is enough for Samba4 for now. The major areas of incompleteness are: - no emulation of setreuid, setresuid or saved uids. These would be needed for use in Samba3 - no emulation of ruid changing. That would also be needed for Samba3 - no attempt to emulate file ownership changing, so code that (for example) tests whether st.st_uid matches geteuid() needs special handling --- lib/uid_wrapper/config.m4 | 16 ++++ lib/uid_wrapper/config.mk | 9 ++ lib/uid_wrapper/uid_wrapper.c | 147 ++++++++++++++++++++++++++++++ lib/uid_wrapper/uid_wrapper.h | 61 +++++++++++++ lib/util/config.mk | 1 + lib/util/util.c | 2 + nsswitch/config.mk | 3 +- selftest/target/Samba4.pm | 5 +- source4/Makefile | 1 + source4/auth/ntlm/config.mk | 2 +- source4/configure.ac | 1 + source4/heimdal_build/config.h | 5 + source4/heimdal_build/internal.mk | 3 +- source4/include/includes.h | 5 + source4/main.mk | 1 + source4/ntvfs/posix/pvfs_acl.c | 8 ++ source4/ntvfs/unixuid/config.mk | 2 +- 17 files changed, 265 insertions(+), 7 deletions(-) create mode 100644 lib/uid_wrapper/config.m4 create mode 100644 lib/uid_wrapper/config.mk create mode 100644 lib/uid_wrapper/uid_wrapper.c create mode 100644 lib/uid_wrapper/uid_wrapper.h diff --git a/lib/uid_wrapper/config.m4 b/lib/uid_wrapper/config.m4 new file mode 100644 index 00000000000..db6537bf959 --- /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 00000000000..1bebc681180 --- /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 00000000000..e009fa0b5c3 --- /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 . + */ + +#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 00000000000..e2df613f504 --- /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 . + */ + +#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 ad39096c565..47e026865e7 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 f49d25865c5..dea140148fa 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; diff --git a/nsswitch/config.mk b/nsswitch/config.mk index 264032e530e..9a04f3bc37a 100644 --- a/nsswitch/config.mk +++ b/nsswitch/config.mk @@ -30,7 +30,8 @@ PRIVATE_DEPENDENCIES = \ LIBWBCLIENT \ LIBTEVENT \ UTIL_TEVENT \ - LIBASYNC_REQ + LIBASYNC_REQ \ + UID_WRAPPER # End BINARY nsstest ################################# diff --git a/selftest/target/Samba4.pm b/selftest/target/Samba4.pm index d2c11e4f321..db5900d0ae4 100644 --- a/selftest/target/Samba4.pm +++ b/selftest/target/Samba4.pm @@ -113,6 +113,8 @@ sub check_or_start($$$) $ENV{NSS_WRAPPER_PASSWD} = $env_vars->{NSS_WRAPPER_PASSWD}; $ENV{NSS_WRAPPER_GROUP} = $env_vars->{NSS_WRAPPER_GROUP}; + $ENV{UID_WRAPPER} = "1"; + # Start slapd before samba, but with the fifo on stdin if (defined($self->{ldap})) { $self->slapd_start($env_vars) or @@ -773,7 +775,6 @@ sub provision($$$$$$$) [tmp] path = $ctx->{tmpdir} read only = no - ntvfs handler = posix posix:sharedelay = 100000 posix:eadb = $ctx->{lockdir}/eadb.tdb posix:oplocktimeout = 3 @@ -782,7 +783,6 @@ sub provision($$$$$$$) [test1] path = $ctx->{tmpdir}/test1 read only = no - ntvfs handler = posix posix:sharedelay = 100000 posix:eadb = $ctx->{lockdir}/eadb.tdb posix:oplocktimeout = 3 @@ -791,7 +791,6 @@ sub provision($$$$$$$) [test2] path = $ctx->{tmpdir}/test2 read only = no - ntvfs handler = posix posix:sharedelay = 100000 posix:eadb = $ctx->{lockdir}/eadb.tdb posix:oplocktimeout = 3 diff --git a/source4/Makefile b/source4/Makefile index d6ae8870666..24e58bc37ab 100644 --- a/source4/Makefile +++ b/source4/Makefile @@ -75,6 +75,7 @@ libcmdlinesrcdir := lib/cmdline poptsrcdir := ../lib/popt socketwrappersrcdir := ../lib/socket_wrapper nsswrappersrcdir := ../lib/nss_wrapper +uidwrappersrcdir := ../lib/uid_wrapper appwebsrcdir := lib/appweb libstreamsrcdir := lib/stream libutilsrcdir := ../lib/util diff --git a/source4/auth/ntlm/config.mk b/source4/auth/ntlm/config.mk index 561d14ad10f..cb9c3b6cc9e 100644 --- a/source4/auth/ntlm/config.mk +++ b/source4/auth/ntlm/config.mk @@ -57,7 +57,7 @@ auth_developer_OBJ_FILES = $(addprefix $(authsrcdir)/ntlm/, auth_developer.o) [MODULE::auth_unix] INIT_FUNCTION = auth_unix_init SUBSYSTEM = auth -PRIVATE_DEPENDENCIES = CRYPT PAM PAM_ERRORS NSS_WRAPPER +PRIVATE_DEPENDENCIES = CRYPT PAM PAM_ERRORS NSS_WRAPPER UID_WRAPPER auth_unix_OBJ_FILES = $(addprefix $(authsrcdir)/ntlm/, auth_unix.o) diff --git a/source4/configure.ac b/source4/configure.ac index 7c5f310aa93..3f10419a42d 100644 --- a/source4/configure.ac +++ b/source4/configure.ac @@ -125,6 +125,7 @@ m4_include(ntvfs/posix/config.m4) m4_include(ntvfs/unixuid/config.m4) m4_include(../lib/socket_wrapper/config.m4) m4_include(../lib/nss_wrapper/config.m4) +m4_include(../lib/uid_wrapper/config.m4) m4_include(auth/config.m4) m4_include(kdc/config.m4) m4_include(ntvfs/sysdep/config.m4) diff --git a/source4/heimdal_build/config.h b/source4/heimdal_build/config.h index 6a82637b2d3..8830942e307 100644 --- a/source4/heimdal_build/config.h +++ b/source4/heimdal_build/config.h @@ -27,4 +27,9 @@ #undef HAVE_KRB5_ENCRYPT_BLOCK +#if defined(UID_WRAPPER) && !defined(UID_WRAPPER_REPLACE) && !defined(UID_WRAPPER_NOT_REPLACE) +#define UID_WRAPPER_REPLACE +#include "../uid_wrapper/uid_wrapper.h" +#endif + #endif diff --git a/source4/heimdal_build/internal.mk b/source4/heimdal_build/internal.mk index c0f3b6be990..52281807b50 100644 --- a/source4/heimdal_build/internal.mk +++ b/source4/heimdal_build/internal.mk @@ -598,7 +598,8 @@ PRIVATE_DEPENDENCIES = \ HEIMDAL_ROKEN_PROGNAME \ HEIMDAL_ROKEN_CLOSEFROM \ RESOLV \ - LIBREPLACE_NETWORK + LIBREPLACE_NETWORK \ + UID_WRAPPER # End SUBSYSTEM HEIMDAL_ROKEN ####################### diff --git a/source4/include/includes.h b/source4/include/includes.h index 4862a62e22c..37c6115f0f5 100644 --- a/source4/include/includes.h +++ b/source4/include/includes.h @@ -73,4 +73,9 @@ #define TALLOC_ABORT(reason) smb_panic(reason) #endif +#if defined(UID_WRAPPER) && !defined(UID_WRAPPER_REPLACE) && !defined(UID_WRAPPER_NOT_REPLACE) +#define UID_WRAPPER_REPLACE +#include "../uid_wrapper/uid_wrapper.h" +#endif + #endif /* _INCLUDES_H */ diff --git a/source4/main.mk b/source4/main.mk index b4a82017c8e..4d7fd584f85 100644 --- a/source4/main.mk +++ b/source4/main.mk @@ -19,6 +19,7 @@ mkinclude lib/events/config.mk mkinclude lib/cmdline/config.mk mkinclude ../lib/socket_wrapper/config.mk mkinclude ../lib/nss_wrapper/config.mk +mkinclude ../lib/uid_wrapper/config.mk mkinclude lib/stream/config.mk mkinclude ../lib/util/config.mk mkinclude ../lib/tdr/config.mk diff --git a/source4/ntvfs/posix/pvfs_acl.c b/source4/ntvfs/posix/pvfs_acl.c index 1adced44aa4..f5a00c08a8f 100644 --- a/source4/ntvfs/posix/pvfs_acl.c +++ b/source4/ntvfs/posix/pvfs_acl.c @@ -473,6 +473,14 @@ NTSTATUS pvfs_access_check_unix(struct pvfs_state *pvfs, max_bits |= SEC_STD_ALL; } +#ifdef UID_WRAPPER_REPLACE + /* when running with the uid wrapper, files will be created + owned by the ruid, but we may have a different simulated + euid. We need to force the permission bits as though the + files owner matches the euid */ + max_bits |= SEC_STD_ALL; +#endif + if (*access_mask == SEC_FLAG_MAXIMUM_ALLOWED) { *access_mask = max_bits; return NT_STATUS_OK; diff --git a/source4/ntvfs/unixuid/config.mk b/source4/ntvfs/unixuid/config.mk index 6377657cec9..105ba2f5358 100644 --- a/source4/ntvfs/unixuid/config.mk +++ b/source4/ntvfs/unixuid/config.mk @@ -3,7 +3,7 @@ [MODULE::ntvfs_unixuid] INIT_FUNCTION = ntvfs_unixuid_init SUBSYSTEM = ntvfs -PRIVATE_DEPENDENCIES = SAMDB NSS_WRAPPER +PRIVATE_DEPENDENCIES = SAMDB NSS_WRAPPER UID_WRAPPER # End MODULE ntvfs_unixuid ################################################ -- 2.34.1