+++ /dev/null
-exec_prefix = /
-libdir = $(exec_prefix)/lib
-
-INSTALL = install
-CC = gcc
-CFLAGS = -O2 -Wall
-
-ALL_CFLAGS = $(CFLAGS) -fPIC
-ALL_LDFLAGS = $(LDFLAGS) -shared -Wl,-x
-
-all: libnss_nonlocal.so.2 linktest
-
-OBJS = nonlocal-passwd.o nonlocal-group.o nonlocal-shadow.o
-
-libnss_nonlocal.so.2: $(OBJS) libnss_nonlocal.map
- $(CC) -o $@ $(ALL_LDFLAGS) -Wl,-soname,$@ -Wl,--version-script=libnss_nonlocal.map $(OBJS) $(LOADLIBES) $(LDLIBS)
-
-%.o: %.c
- $(CC) -c $(ALL_CFLAGS) $(CPPFLAGS) $<
-
-nonlocal-passwd.o: nonlocal-passwd.c nsswitch-internal.h nonlocal.h
-nonlocal-group.o: nonlocal-group.c nsswitch-internal.h nonlocal.h
-nonlocal-shadow.o: nonlocal-shadow.c nsswitch-internal.h nonlocal.h
-
-linktest: libnss_nonlocal.so.2
- $(CC) $(LDFLAGS) -nostdlib -Wl,--entry=0 -o /dev/null $^
-
-install: libnss_nonlocal.so.2
- $(INSTALL) -d $(DESTDIR)$(libdir)
- $(INSTALL) -m a+r,u+w $< $(DESTDIR)$(libdir)/
-
-clean:
- rm -f *.so.* *.o
-
-.PHONY: all linktest install clean
--- /dev/null
+lib_LTLIBRARIES = libnss_nonlocal.la
+libnss_nonlocal_la_SOURCES = \
+ nonlocal-passwd.c nonlocal-group.c nonlocal-shadow.c \
+ nonlocal.h nsswitch-internal.h
+libnss_nonlocal_la_LDFLAGS = \
+ -version-info 2:0:0 \
+ -export-symbols-regex '^_nss_nonlocal_'
+
+noinst_PROGRAMS = .linktest
+_linktest_SOURCES =
+_linktest_LDADD = libnss_nonlocal.la
+_linktest_LDFLAGS = -nostdlib -entry=0
+
+install-exec-hook:
+ rm -f $(DESTDIR)$(libdir)/libnss_nonlocal.so
+ rm -f $(DESTDIR)$(libdir)/libnss_nonlocal.la
--- /dev/null
+AC_INIT([nss_nonlocal], [1.7], [andersk@mit.edu])
+AC_CANONICAL_TARGET
+AM_INIT_AUTOMAKE([-Wall -Werror foreign])
+
+AC_PREFIX_DEFAULT([/])
+AC_DISABLE_STATIC
+AC_PROG_CC
+AC_PROG_INSTALL
+AC_PROG_LIBTOOL
+
+case "$target_cpu" in
+ i386 | i486 | i586 | i686 | i786)
+ AC_DEFINE([USE_REGPARMS], [],
+ [Define if the regparm attribute shall be used for local functions (gcc on ix86 only).])
+ ;;
+esac
+
+AC_CONFIG_HEADERS([config.h])
+AC_CONFIG_FILES([Makefile])
+AC_OUTPUT
+++ /dev/null
-GLIBC_2.0 {
- global:
- _nss_nonlocal_setpwent;
- _nss_nonlocal_endpwent;
- _nss_nonlocal_getpwent_r;
- _nss_nonlocal_getpwuid_r;
- _nss_nonlocal_getpwnam_r;
-
- _nss_nonlocal_setspent;
- _nss_nonlocal_endspent;
- _nss_nonlocal_getspent_r;
- _nss_nonlocal_getspnam_r;
-
- _nss_nonlocal_setgrent;
- _nss_nonlocal_endgrent;
- _nss_nonlocal_getgrent_r;
- _nss_nonlocal_getgrgid_r;
- _nss_nonlocal_getgrnam_r;
-
- _nss_nonlocal_initgroups_dyn;
-
- local:
- *;
-};
#include "nsswitch-internal.h"
#include "nonlocal.h"
-#define MAGIC_LOCAL_GR_BUFLEN (sysconf(_SC_GETGR_R_SIZE_MAX) + 7)
#define MAGIC_NONLOCAL_GROUPNAME "nss-nonlocal-users"
#define MAGIC_LOCAL_GROUPNAME "nss-local-users"
+enum nss_status
+_nss_nonlocal_getgrnam_r(const char *name, struct group *grp,
+ char *buffer, size_t buflen, int *errnop);
+
+enum nss_status
+_nss_nonlocal_getgrgid_r(gid_t gid, struct group *grp,
+ char *buffer, size_t buflen, int *errnop);
+
+
static service_user *
nss_group_nonlocal_database(void)
{
enum nss_status
check_nonlocal_gid(const char *user, gid_t gid, int *errnop)
{
- enum nss_status status = NSS_STATUS_SUCCESS;
+ static const char *fct_name = "getgrgid_r";
+ static service_user *startp = NULL;
+ static void *fct_start = NULL;
+ enum nss_status status;
+ service_user *nip;
+ union {
+ enum nss_status (*l)(gid_t gid, struct group *grp,
+ char *buffer, size_t buflen, int *errnop);
+ void *ptr;
+ } fct;
struct group gbuf;
- struct group *gbufp = &gbuf;
- int ret;
int old_errno = errno;
- int buflen = MAGIC_LOCAL_GR_BUFLEN;
+
+ int buflen = sysconf(_SC_GETGR_R_SIZE_MAX);
char *buf = malloc(buflen);
if (buf == NULL) {
*errnop = ENOMEM;
errno = old_errno;
return NSS_STATUS_TRYAGAIN;
}
- errno = 0;
- ret = getgrgid_r(gid, gbufp, buf, buflen, &gbufp);
- if (ret != 0) {
- *errnop = old_errno;
- status = NSS_STATUS_TRYAGAIN;
- } else if (gbufp != NULL) {
+
+ if (fct_start == NULL &&
+ __nss_group_lookup(&startp, fct_name, &fct_start) != 0) {
+ free(buf);
+ return NSS_STATUS_UNAVAIL;
+ }
+ nip = startp;
+ fct.ptr = fct_start;
+ do {
+ if (fct.l == _nss_nonlocal_getgrgid_r)
+ status = NSS_STATUS_NOTFOUND;
+ else
+ status = DL_CALL_FCT(fct.l, (gid, &gbuf, buf, buflen, errnop));
+ if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE)
+ break;
+ } while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
+
+ if (status == NSS_STATUS_SUCCESS) {
syslog(LOG_WARNING, "nss_nonlocal: removing local group %u (%s) from non-local user %s\n", gbuf.gr_gid, gbuf.gr_name, user);
status = NSS_STATUS_NOTFOUND;
+ } else if (status != NSS_STATUS_TRYAGAIN) {
+ status = NSS_STATUS_SUCCESS;
}
+
free(buf);
- errno = old_errno;
return status;
}
enum nss_status
get_local_group(const char *name, struct group *grp, char *buffer, size_t buflen, int *errnop)
{
- enum nss_status status = NSS_STATUS_NOTFOUND;
+ static const char *fct_name = "getgrnam_r";
+ static service_user *startp = NULL;
+ static void *fct_start = NULL;
+ enum nss_status status;
+ service_user *nip;
+ union {
+ enum nss_status (*l)(const char *name, struct group *grp,
+ char *buffer, size_t buflen, int *errnop);
+ void *ptr;
+ } fct;
struct group gbuf;
- struct group *gbufp = &gbuf;
- int ret, n;
+ int n;
int old_errno = errno;
- int len = MAGIC_LOCAL_GR_BUFLEN;
+
+ int len = sysconf(_SC_GETGR_R_SIZE_MAX);
char *buf = malloc(len);
if (buf == NULL) {
*errnop = ENOMEM;
errno = old_errno;
return NSS_STATUS_TRYAGAIN;
}
- errno = 0;
- ret = getgrnam_r(name, gbufp, buf, len, &gbufp);
- if (ret != 0) {
- *errnop = old_errno;
+
+ if (fct_start == NULL &&
+ __nss_group_lookup(&startp, fct_name, &fct_start) != 0) {
+ free(buf);
+ return NSS_STATUS_UNAVAIL;
+ }
+ nip = startp;
+ fct.ptr = fct_start;
+ do {
+ if (fct.l == _nss_nonlocal_getgrnam_r)
+ status = NSS_STATUS_NOTFOUND;
+ else
+ status = DL_CALL_FCT(fct.l, (name, &gbuf, buf, buflen, errnop));
+ if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE)
+ break;
+ } while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
+
+ if (status != NSS_STATUS_SUCCESS)
+ goto get_local_group_done;
+
+ n = snprintf(buffer, buflen, "%s", gbuf.gr_name);
+ if (n < 0 || n >= buflen) {
+ *errnop = ERANGE;
status = NSS_STATUS_TRYAGAIN;
- } else if (gbufp != NULL) {
- status = NSS_STATUS_SUCCESS;
+ goto get_local_group_done;
+ }
+ grp->gr_name = buffer;
+ buffer += n;
+ buflen -= n;
- n = snprintf(buffer, buflen, "%s", gbufp->gr_name);
- if (n < 0 || n >= buflen) {
- *errnop = ERANGE;
- status = NSS_STATUS_TRYAGAIN;
- goto get_local_group_done;
- }
- grp->gr_name = buffer;
- buffer += n;
- buflen -= n;
-
- n = snprintf(buffer, buflen, "%s", gbufp->gr_passwd);
- if (n < 0 || n >= buflen) {
- *errnop = ERANGE;
- status = NSS_STATUS_TRYAGAIN;
- goto get_local_group_done;
- }
- grp->gr_passwd = buffer;
- buffer += n;
- buflen -= n;
+ n = snprintf(buffer, buflen, "%s", gbuf.gr_passwd);
+ if (n < 0 || n >= buflen) {
+ *errnop = ERANGE;
+ status = NSS_STATUS_TRYAGAIN;
+ goto get_local_group_done;
+ }
+ grp->gr_passwd = buffer;
+ buffer += n;
+ buflen -= n;
- grp->gr_gid = gbufp->gr_gid;
+ grp->gr_gid = gbuf.gr_gid;
- if (buflen < sizeof(void *)) {
- *errnop = ERANGE;
- status = NSS_STATUS_TRYAGAIN;
- goto get_local_group_done;
- }
- *(void **)buffer = NULL;
- buffer += sizeof(void *);
- buflen -= sizeof(void *);
+ if (buflen < sizeof(void *)) {
+ *errnop = ERANGE;
+ status = NSS_STATUS_TRYAGAIN;
+ goto get_local_group_done;
}
+ *(void **)buffer = NULL;
+ buffer += sizeof(void *);
+ buflen -= sizeof(void *);
+
get_local_group_done:
free(buf);
- errno = old_errno;
return status;
}
enum nss_status status;
char *nonlocal_ignore = getenv(NONLOCAL_IGNORE_ENV);
- if (buflen == MAGIC_LOCAL_GR_BUFLEN ||
- (nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0'))
+ if (nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0')
return NSS_STATUS_UNAVAIL;
if (grent_nip == NULL) {
} fct;
char *nonlocal_ignore = getenv(NONLOCAL_IGNORE_ENV);
- if (buflen == MAGIC_LOCAL_GR_BUFLEN ||
- (nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0'))
+ if (nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0')
return NSS_STATUS_UNAVAIL;
nip = nss_group_nonlocal_database();
} fct;
char *nonlocal_ignore = getenv(NONLOCAL_IGNORE_ENV);
- if (buflen == MAGIC_LOCAL_GR_BUFLEN ||
- (nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0'))
+ if (nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0')
return NSS_STATUS_UNAVAIL;
nip = nss_group_nonlocal_database();
/* Check that the user is a nonlocal user before adding any groups. */
status = check_nonlocal_user(user, errnop);
- if (status == NSS_STATUS_NOTFOUND)
- is_local = 1;
- else if (status != NSS_STATUS_SUCCESS)
+ if (status == NSS_STATUS_TRYAGAIN)
return status;
+ else if (status != NSS_STATUS_SUCCESS)
+ is_local = 1;
int old_errno = errno;
}
status = get_local_group(MAGIC_LOCAL_GROUPNAME,
&local_users_group, buffer, buflen, errnop);
- if (status == NSS_STATUS_NOTFOUND) {
+ if (status == NSS_STATUS_SUCCESS) {
+ local_users_gid = local_users_group.gr_gid;
+ } else if (status == NSS_STATUS_TRYAGAIN) {
+ free(buffer);
+ return status;
+ } else {
syslog(LOG_WARNING, "nss_nonlocal: Group %s does not exist locally!",
MAGIC_LOCAL_GROUPNAME);
local_users_gid = -1;
- } else if (status != NSS_STATUS_SUCCESS) {
- return status;
- } else
- local_users_gid = local_users_group.gr_gid;
+ }
free(buffer);
if (is_local) {
}
status = get_local_group(MAGIC_NONLOCAL_GROUPNAME,
&nonlocal_users_group, buffer, buflen, errnop);
- if (status == NSS_STATUS_NOTFOUND) {
+ if (status == NSS_STATUS_SUCCESS) {
+ gid = nonlocal_users_group.gr_gid;
+ } else if (status == NSS_STATUS_TRYAGAIN) {
+ free(buffer);
+ return status;
+ } else {
syslog(LOG_WARNING, "nss_nonlocal: Group %s does not exist locally!",
MAGIC_NONLOCAL_GROUPNAME);
gid = -1;
- } else if (status != NSS_STATUS_SUCCESS) {
- errno = old_errno;
- return status;
- } else
- gid = nonlocal_users_group.gr_gid;
+ }
free(buffer);
}
}
}
- errno = old_errno;
-
if (is_local)
return NSS_STATUS_SUCCESS;
status = check_nonlocal_gid(user, (*groupsp)[in], &nonlocal_errno);
if (status == NSS_STATUS_SUCCESS) {
(*groupsp)[out++] = (*groupsp)[in];
- } else if (status != NSS_STATUS_NOTFOUND) {
+ } else if (status == NSS_STATUS_TRYAGAIN) {
*start = out;
*errnop = nonlocal_errno;
return status;
#include "nsswitch-internal.h"
#include "nonlocal.h"
-#define MAGIC_LOCAL_PW_BUFLEN (sysconf(_SC_GETPW_R_SIZE_MAX) + 7)
+
+enum nss_status
+_nss_nonlocal_getpwuid_r(uid_t uid, struct passwd *pwd,
+ char *buffer, size_t buflen, int *errnop);
+enum nss_status
+_nss_nonlocal_getpwnam_r(const char *name, struct passwd *pwd,
+ char *buffer, size_t buflen, int *errnop);
static service_user *
enum nss_status
check_nonlocal_uid(const char *user, uid_t uid, int *errnop)
{
- enum nss_status status = NSS_STATUS_SUCCESS;
+ static const char *fct_name = "getpwuid_r";
+ static service_user *startp = NULL;
+ static void *fct_start = NULL;
+ enum nss_status status;
+ service_user *nip;
+ union {
+ enum nss_status (*l)(uid_t uid, struct passwd *pwd,
+ char *buffer, size_t buflen, int *errnop);
+ void *ptr;
+ } fct;
struct passwd pwbuf;
- struct passwd *pwbufp = &pwbuf;
- int ret;
int old_errno = errno;
- int buflen = MAGIC_LOCAL_PW_BUFLEN;
+
+ int buflen = sysconf(_SC_GETPW_R_SIZE_MAX);
char *buf = malloc(buflen);
if (buf == NULL) {
*errnop = ENOMEM;
errno = old_errno;
return NSS_STATUS_TRYAGAIN;
}
- errno = 0;
- ret = getpwuid_r(uid, pwbufp, buf, buflen, &pwbufp);
- if (ret != 0) {
- *errnop = errno;
- status = NSS_STATUS_TRYAGAIN;
- } else if (pwbufp != NULL) {
+
+ if (fct_start == NULL &&
+ __nss_passwd_lookup(&startp, fct_name, &fct_start) != 0) {
+ free(buf);
+ return NSS_STATUS_UNAVAIL;
+ }
+ nip = startp;
+ fct.ptr = fct_start;
+ do {
+ if (fct.l == _nss_nonlocal_getpwuid_r)
+ status = NSS_STATUS_NOTFOUND;
+ else
+ status = DL_CALL_FCT(fct.l, (uid, &pwbuf, buf, buflen, errnop));
+ if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE)
+ break;
+ } while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
+
+ if (status == NSS_STATUS_SUCCESS) {
syslog(LOG_ERR, "nss_nonlocal: possible spoofing attack: non-local user %s has same UID as local user %s!\n", user, pwbuf.pw_name);
status = NSS_STATUS_NOTFOUND;
+ } else if (status != NSS_STATUS_TRYAGAIN) {
+ status = NSS_STATUS_SUCCESS;
}
+
free(buf);
- errno = old_errno;
return status;
}
enum nss_status
check_nonlocal_user(const char *user, int *errnop)
{
- enum nss_status status = NSS_STATUS_SUCCESS;
+ static const char *fct_name = "getpwnam_r";
+ static service_user *startp = NULL;
+ static void *fct_start = NULL;
+ enum nss_status status;
+ service_user *nip;
+ union {
+ enum nss_status (*l)(const char *name, struct passwd *pwd,
+ char *buffer, size_t buflen, int *errnop);
+ void *ptr;
+ } fct;
struct passwd pwbuf;
- struct passwd *pwbufp = &pwbuf;
- int ret;
int old_errno = errno;
- int buflen = MAGIC_LOCAL_PW_BUFLEN;
+
+ int buflen = sysconf(_SC_GETPW_R_SIZE_MAX);
char *buf = malloc(buflen);
if (buf == NULL) {
*errnop = ENOMEM;
errno = old_errno;
return NSS_STATUS_TRYAGAIN;
}
- errno = 0;
- ret = getpwnam_r(user, pwbufp, buf, buflen, &pwbufp);
- if (ret != 0) {
- *errnop = errno;
- status = NSS_STATUS_TRYAGAIN;
- } else if (pwbufp != NULL) {
- status = NSS_STATUS_NOTFOUND;
+
+ if (fct_start == NULL &&
+ __nss_passwd_lookup(&startp, fct_name, &fct_start) != 0) {
+ free(buf);
+ return NSS_STATUS_UNAVAIL;
}
+ nip = startp;
+ fct.ptr = fct_start;
+ do {
+ if (fct.l == _nss_nonlocal_getpwnam_r)
+ status = NSS_STATUS_NOTFOUND;
+ else
+ status = DL_CALL_FCT(fct.l, (user, &pwbuf, buf, buflen, errnop));
+ if (status == NSS_STATUS_TRYAGAIN && *errnop == ERANGE)
+ break;
+ } while (__nss_next(&nip, fct_name, &fct.ptr, status, 0) == 0);
+
+ if (status == NSS_STATUS_SUCCESS)
+ status = NSS_STATUS_NOTFOUND;
+ else if (status != NSS_STATUS_TRYAGAIN)
+ status = NSS_STATUS_SUCCESS;
+
free(buf);
- errno = old_errno;
return status;
}
enum nss_status status;
char *nonlocal_ignore = getenv(NONLOCAL_IGNORE_ENV);
- if (buflen == MAGIC_LOCAL_PW_BUFLEN ||
- (nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0'))
+ if (nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0')
return NSS_STATUS_UNAVAIL;
if (pwent_nip == NULL) {
int group_errno;
char *nonlocal_ignore = getenv(NONLOCAL_IGNORE_ENV);
- if (buflen == MAGIC_LOCAL_PW_BUFLEN ||
- (nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0'))
+ if (nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0')
return NSS_STATUS_UNAVAIL;
nip = nss_passwd_nonlocal_database();
int group_errno;
char *nonlocal_ignore = getenv(NONLOCAL_IGNORE_ENV);
- if (buflen == MAGIC_LOCAL_PW_BUFLEN ||
- (nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0'))
+ if (nonlocal_ignore != NULL && nonlocal_ignore[0] != '\0')
return NSS_STATUS_UNAVAIL;
nip = nss_passwd_nonlocal_database();
#ifndef NONLOCAL_H
#define NONLOCAL_H
+
+#include "config.h"
+
enum nss_status check_nonlocal_uid(const char *user, uid_t uid, int *errnop);
enum nss_status check_nonlocal_gid(const char *user, gid_t gid, int *errnop);
enum nss_status check_nonlocal_user(const char *user, int *errnop);
+
#define NONLOCAL_IGNORE_ENV "NSS_NONLOCAL_IGNORE"
+
#endif /* NON_LOCAL_H */
#ifndef NSSWITCH_INTERNAL_H
#define NSSWITCH_INTERNAL_H
-typedef struct service_user service_user;
+#include "config.h"
-extern int
-__nss_next (service_user **ni, const char *fct_name, void **fctp, int status,
- int all_values);
+/* glibc/config.h.in */
+#if defined USE_REGPARMS && !defined PROF && !defined __BOUNDED_POINTERS__
+# define internal_function __attribute__ ((regparm (3), stdcall))
+#else
+# define internal_function
+#endif
-extern int
-__nss_database_lookup (const char *database,
- const char *alternative_name,
- const char *defconfig, service_user **ni);
+/* glibc/nss/nsswitch.h */
+typedef struct service_user service_user;
-extern int
-__nss_configure_lookup (const char *dbname, const char *service_line);
+extern int __nss_next (service_user **ni, const char *fct_name, void **fctp,
+ int status, int all_values);
+extern int __nss_database_lookup (const char *database,
+ const char *alternative_name,
+ const char *defconfig, service_user **ni);
+extern void *__nss_lookup_function (service_user *ni, const char *fct_name);
-extern void
-*__nss_lookup_function (service_user *ni, const char *fct_name);
+/* glibc/nss/XXX-lookup.c */
+extern int __nss_passwd_lookup (service_user **ni, const char *fct_name,
+ void **fctp) internal_function;
+extern int __nss_group_lookup (service_user **ni, const char *fct_name,
+ void **fctp) internal_function;
#endif /* NSSWITCH_INTERNAL_H */
andersk / nss_nonlocal.git / commitdiff
