On Sun, 2004-12-12 at 23:59 +0000, Dave Page wrote:
> Sounds reasonable to me.
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Attached is a patch that implements this.
src/port/backend/win32/security.c is moved to src/port/win32_security.c,
and conditionally added to LIBOBJS. Note that I don't have much
experience with the build system, and less still with the Win32 port, so
please let me know if there's a better way to do this. Also, I don't
have a Windows build environment -- could someone verify whether this
builds on Win32?
-Neil
#
# delete_file "src/backend/port/win32/security.c"
#
# add_file "src/port/win32_security.c"
#
# patch "src/Makefile.global.in"
# from [4183afa6d7d7945d4e29a3aa30a18c312251ed8e]
# to [6a0e08d33676e1c8c17a296653edbbd8afd5a2c2]
#
# patch "src/backend/port/win32/Makefile"
# from [009b45987d1428cbbd1d0bb78ee55868f9729ca3]
# to [97a5831267b24977fa4f3770d06e0fef7884bf2f]
#
# patch "src/bin/pg_resetxlog/pg_resetxlog.c"
# from [df43f11496af96317f9f927f84c488ce33492c93]
# to [58ddbddf7765426d60a8fddaaea2034e1e259cfb]
#
# patch "src/include/port/win32.h"
# from [39b47f71111b5c1eaafadaff48cb2c5ccf60ca59]
# to [e346ae59f9fde1a95a46ccf81ba3ca8c50bf8cef]
#
# patch "src/port/win32_security.c"
# from []
# to [4766ac4547aa1648eaa8596ce31ce12da763a3c8]
#
--- src/Makefile.global.in
+++ src/Makefile.global.in
@@ -362,6 +362,10 @@
LIBOBJS = @LIBOBJS@ dirmod.o exec.o noblock.o path.o pipe.o pgsleep.o pgstrcasecmp.o sprompt.o thread.o
+ifeq ($(PORTNAME),win32)
+LIBOBJS += win32_security.o
+endif
+
ifneq (,$(LIBOBJS))
LIBS := -lpgport $(LIBS)
ifdef PGXS
--- src/backend/port/win32/Makefile
+++ src/backend/port/win32/Makefile
@@ -12,7 +12,7 @@
top_builddir = ../../../..
include $(top_builddir)/src/Makefile.global
-OBJS = sema.o shmem.o timer.o socket.o signal.o security.o error.o
+OBJS = sema.o shmem.o timer.o socket.o signal.o error.o
all: SUBSYS.o
--- src/bin/pg_resetxlog/pg_resetxlog.c
+++ src/bin/pg_resetxlog/pg_resetxlog.c
@@ -181,6 +181,32 @@
snprintf(ControlFilePath, MAXPGPATH, "%s/global/pg_control", DataDir);
/*
+ * Don't allow pg_resetxlog to be run as root, to avoid
+ * overwriting the ownership of files in the data directory. We
+ * need only check for root -- any other user won't have
+ * sufficient permissions to modify files in the data directory.
+ */
+#ifdef WIN32
+ if (pgwin32_is_admin())
+ {
+ fprintf(stderr, _("%s: cannot be executed by a user with "
+ "administrative permissions\n"), progname);
+ fprintf(stderr, _("You must run %s as the PostgreSQL superuser.\n"),
+ progname);
+ exit(1);
+ }
+#else
+ if (geteuid() == 0)
+ {
+ fprintf(stderr, _("%s: cannot be executed by \"root\"\n"),
+ progname);
+ fprintf(stderr, _("You must run %s as the PostgreSQL superuser.\n"),
+ progname);
+ exit(1);
+ }
+#endif
+
+ /*
* Check for a postmaster lock file --- if there is one, refuse to
* proceed, on grounds we might be interfering with a live
* installation.
--- src/include/port/win32.h
+++ src/include/port/win32.h
@@ -145,15 +145,14 @@
const char *pgwin32_socket_strerror(int err);
int pgwin32_waitforsinglesocket(SOCKET s, int what);
-
-/* in backend/port/win32/security.c */
-extern int pgwin32_is_admin(void);
-extern int pgwin32_is_service(void);
#endif
/* in backend/port/win32/error.c */
void _dosmaperr(unsigned long);
+/* in port/win32_security.c */
+extern int pgwin32_is_admin(void);
+extern int pgwin32_is_service(void);
#define WEXITSTATUS(w) (((w) >> 8) & 0xff)
#define WIFEXITED(w) (((w) & 0xff) == 0)
--- src/port/win32_security.c
+++ src/port/win32_security.c
@@ -0,0 +1,248 @@
+/*-------------------------------------------------------------------------
+ *
+ * win32_security.c
+ * Microsoft Windows Win32 Security Support Functions
+ *
+ * Portions Copyright (c) 1996-2004, PostgreSQL Global Development Group
+ *
+ * IDENTIFICATION
+ * $PostgreSQL: pgsql/src/backend/port/win32/security.c,v 1.7 2004/11/16 19:52:22 tgl Exp $
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#include "postgres.h"
+
+
+static BOOL pgwin32_get_dynamic_tokeninfo(HANDLE token,
+ TOKEN_INFORMATION_CLASS class, char **InfoBuffer,
+ char *errbuf, int errsize);
+
+/*
+ * Returns nonzero if the current user has administrative privileges,
+ * or zero if not.
+ *
+ * Note: this cannot use ereport() because it's called too early during
+ * startup.
+ */
+int
+pgwin32_is_admin(void)
+{
+ HANDLE AccessToken;
+ char *InfoBuffer = NULL;
+ char errbuf[256];
+ PTOKEN_GROUPS Groups;
+ PSID AdministratorsSid;
+ PSID PowerUsersSid;
+ SID_IDENTIFIER_AUTHORITY NtAuthority = {SECURITY_NT_AUTHORITY};
+ UINT x;
+ BOOL success;
+
+ if (!OpenProcessToken(GetCurrentProcess(), TOKEN_READ, &AccessToken))
+ {
+ write_stderr("could not open process token: error code %d\n",
+ (int) GetLastError());
+ exit(1);
+ }
+
+ if (!pgwin32_get_dynamic_tokeninfo(AccessToken, TokenGroups,
+ &InfoBuffer, errbuf, sizeof(errbuf)))
+ {
+ write_stderr(errbuf);
+ exit(1);
+ }
+
+ Groups = (PTOKEN_GROUPS) InfoBuffer;
+
+ CloseHandle(AccessToken);
+
+ if (!AllocateAndInitializeSid(&NtAuthority, 2,
+ SECURITY_BUILTIN_DOMAIN_RID, DOMAIN_ALIAS_RID_ADMINS, 0, 0, 0, 0, 0,
+ 0, &AdministratorsSid))
+ {
+ write_stderr("could not get SID for Administrators group: error code %d\n",
+ (int) GetLastError());
+ exit(1);
+ }
+
+ if (!AllocateAndInitializeSid(&NtAuthority, 2,
+ SECURITY_BUILTIN_DOMAIN_RID, DOMAIN_ALIAS_RID_POWER_USERS, 0, 0, 0, 0, 0,
+ 0, &PowerUsersSid))
+ {
+ write_stderr("could not get SID for PowerUsers group: error code %d\n",
+ (int) GetLastError());
+ exit(1);
+ }
+
+ success = FALSE;
+
+ for (x = 0; x < Groups->GroupCount; x++)
+ {
+ if (EqualSid(AdministratorsSid, Groups->Groups[x].Sid) ||
+ EqualSid(PowerUsersSid, Groups->Groups[x].Sid))
+ {
+ success = TRUE;
+ break;
+ }
+ }
+
+ free(InfoBuffer);
+ FreeSid(AdministratorsSid);
+ FreeSid(PowerUsersSid);
+ return success;
+}
+
+/*
+ * We consider ourselves running as a service if one of the following is
+ * true:
+ *
+ * 1) We are running as Local System (only used by services)
+ * 2) Our token contains SECURITY_SERVICE_RID (automatically added to the
+ * process token by the SCM when starting a service)
+ *
+ * Return values:
+ * 0 = Not service
+ * 1 = Service
+ * -1 = Error
+ *
+ * Note: we can't report errors via either ereport (we're called too early)
+ * or write_stderr (because that calls this). We are therefore reduced to
+ * writing directly on stderr, which sucks, but we have few alternatives.
+ */
+int
+pgwin32_is_service(void)
+{
+ static int _is_service = -1;
+ HANDLE AccessToken;
+ char *InfoBuffer = NULL;
+ char errbuf[256];
+ PTOKEN_GROUPS Groups;
+ PTOKEN_USER User;
+ PSID ServiceSid;
+ PSID LocalSystemSid;
+ SID_IDENTIFIER_AUTHORITY NtAuthority = {SECURITY_NT_AUTHORITY};
+ UINT x;
+
+ /* Only check the first time */
+ if (_is_service != -1)
+ return _is_service;
+
+ if (!OpenProcessToken(GetCurrentProcess(), TOKEN_READ, &AccessToken))
+ {
+ fprintf(stderr, "could not open process token: error code %d\n",
+ (int) GetLastError());
+ return -1;
+ }
+
+ /* First check for local system */
+ if (!pgwin32_get_dynamic_tokeninfo(AccessToken, TokenUser, &InfoBuffer,
+ errbuf, sizeof(errbuf)))
+ {
+ fprintf(stderr,errbuf);
+ return -1;
+ }
+
+ User = (PTOKEN_USER) InfoBuffer;
+
+ if (!AllocateAndInitializeSid(&NtAuthority, 1,
+ SECURITY_LOCAL_SYSTEM_RID, 0, 0, 0, 0, 0, 0, 0,
+ &LocalSystemSid))
+ {
+ fprintf(stderr, "could not get SID for local system account\n");
+ CloseHandle(AccessToken);
+ return -1;
+ }
+
+ if (EqualSid(LocalSystemSid, User->User.Sid))
+ {
+ FreeSid(LocalSystemSid);
+ free(InfoBuffer);
+ CloseHandle(AccessToken);
+ _is_service = 1;
+ return _is_service;
+ }
+
+ FreeSid(LocalSystemSid);
+ free(InfoBuffer);
+
+ /* Now check for group SID */
+ if (!pgwin32_get_dynamic_tokeninfo(AccessToken, TokenGroups, &InfoBuffer,
+ errbuf, sizeof(errbuf)))
+ {
+ fprintf(stderr,errbuf);
+ return -1;
+ }
+
+ Groups = (PTOKEN_GROUPS) InfoBuffer;
+
+ if (!AllocateAndInitializeSid(&NtAuthority, 1,
+ SECURITY_SERVICE_RID, 0, 0, 0, 0, 0, 0, 0,
+ &ServiceSid))
+ {
+ fprintf(stderr, "could not get SID for service group\n");
+ free(InfoBuffer);
+ CloseHandle(AccessToken);
+ return -1;
+ }
+
+ _is_service = 0;
+ for (x = 0; x < Groups->GroupCount; x++)
+ {
+ if (EqualSid(ServiceSid, Groups->Groups[x].Sid))
+ {
+ _is_service = 1;
+ break;
+ }
+ }
+
+ free(InfoBuffer);
+ FreeSid(ServiceSid);
+
+ CloseHandle(AccessToken);
+
+ return _is_service;
+}
+
+
+/*
+ * Call GetTokenInformation() on a token and return a dynamically sized
+ * buffer with the information in it. This buffer must be free():d by
+ * the calling function!
+ */
+static BOOL
+pgwin32_get_dynamic_tokeninfo(HANDLE token, TOKEN_INFORMATION_CLASS class,
+ char **InfoBuffer, char *errbuf, int errsize)
+{
+ DWORD InfoBufferSize;
+
+ if (GetTokenInformation(token, class, NULL, 0, &InfoBufferSize))
+ {
+ snprintf(errbuf,errsize,"could not get token information: got zero size\n");
+ return FALSE;
+ }
+
+ if (GetLastError() != ERROR_INSUFFICIENT_BUFFER)
+ {
+ snprintf(errbuf,errsize,"could not get token information: error code %d\n",
+ (int) GetLastError());
+ return FALSE;
+ }
+
+ *InfoBuffer = malloc(InfoBufferSize);
+ if (*InfoBuffer == NULL)
+ {
+ snprintf(errbuf,errsize,"could not allocate %d bytes for token information\n",
+ (int) InfoBufferSize);
+ return FALSE;
+ }
+
+ if (!GetTokenInformation(token, class, *InfoBuffer,
+ InfoBufferSize, &InfoBufferSize))
+ {
+ snprintf(errbuf,errsize,"could not get token information: error code %d\n",
+ (int) GetLastError());
+ return FALSE;
+ }
+
+ return TRUE;
+}
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