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diff --git a/aclocal/kerberos5.m4 b/aclocal/kerberos5.m4
index 0bf35d3..8a0f3e4 100644
--- a/aclocal/kerberos5.m4
+++ b/aclocal/kerberos5.m4
@@ -43,15 +43,6 @@ AC_DEFUN([AC_KERBEROS_V5],[
-f $dir/lib/libgssapi_krb5.so \) ; then
AC_DEFINE(HAVE_KRB5, 1, [Define this if you have MIT Kerberos libraries])
KRBDIR="$dir"
- dnl If we are using MIT K5 1.3.1 and before, we *MUST* use the
- dnl private function (gss_krb5_ccache_name) to get correct
- dnl behavior of changing the ccache used by gssapi.
- dnl Starting in 1.3.2, we *DO NOT* want to use
- dnl gss_krb5_ccache_name, instead we want to set KRB5CCNAME
- dnl to get gssapi to use a different ccache
- if test $K5VERS -le 131; then
- AC_DEFINE(USE_GSS_KRB5_CCACHE_NAME, 1, [Define this if the private function, gss_krb5_cache_name, must be used to tell the Kerberos library which credentials cache to use. Otherwise, this is done by setting the KRB5CCNAME environment variable])
- fi
gssapi_lib=gssapi_krb5
break
dnl The following ugly hack brought on by the split installation
@@ -92,8 +83,6 @@ AC_DEFUN([AC_KERBEROS_V5],[
AC_DEFINE(HAVE_LUCID_CONTEXT_SUPPORT, 1, [Define this if the Kerberos GSS library supports gss_krb5_export_lucid_sec_context]), ,$KRBLIBS)
AC_CHECK_LIB($gssapi_lib, gss_krb5_set_allowable_enctypes,
AC_DEFINE(HAVE_SET_ALLOWABLE_ENCTYPES, 1, [Define this if the Kerberos GSS library supports gss_krb5_set_allowable_enctypes]), ,$KRBLIBS)
- AC_CHECK_LIB($gssapi_lib, gss_krb5_ccache_name,
- AC_DEFINE(HAVE_GSS_KRB5_CCACHE_NAME, 1, [Define this if the Kerberos GSS library supports gss_krb5_ccache_name]), ,$KRBLIBS)
AC_CHECK_LIB($gssapi_lib, gss_krb5_free_lucid_sec_context,
AC_DEFINE(HAVE_GSS_KRB5_FREE_LUCID_SEC_CONTEXT, 1, [Define this if the Kerberos GSS library supports gss_krb5_free_lucid_sec_context]), ,$KRBLIBS)
diff --git a/aclocal/libpthread.m4 b/aclocal/libpthread.m4
new file mode 100644
index 0000000..e87d2a0
--- /dev/null
+++ b/aclocal/libpthread.m4
@@ -0,0 +1,13 @@
+dnl Checks for pthreads library and headers
+dnl
+AC_DEFUN([AC_LIBPTHREAD], [
+
+ dnl Check for library, but do not add -lpthreads to LIBS
+ AC_CHECK_LIB([pthread], [pthread_create], [LIBPTHREAD=-lpthread],
+ [AC_MSG_ERROR([libpthread not found.])])
+ AC_SUBST(LIBPTHREAD)
+
+ AC_CHECK_HEADERS([pthread.h], ,
+ [AC_MSG_ERROR([libpthread headers not found.])])
+
+])dnl
diff --git a/configure.ac b/configure.ac
index 4ee4db5..56f7f3e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -355,6 +355,9 @@ if test "$enable_gss" = yes; then
dnl Invoked after AC_KERBEROS_V5; AC_LIBRPCSECGSS needs to have KRBLIBS set
AC_LIBRPCSECGSS
+ dnl Check for pthreads
+ AC_LIBPTHREAD
+
dnl librpcsecgss already has a dependency on libgssapi,
dnl but we need to make sure we get the right version
if test "$enable_gss" = yes; then
diff --git a/utils/gssd/Makefile.am b/utils/gssd/Makefile.am
index fd488a1..f387c16 100644
--- a/utils/gssd/Makefile.am
+++ b/utils/gssd/Makefile.am
@@ -42,7 +42,8 @@ gssd_LDADD = \
$(RPCSECGSS_LIBS) \
$(KRBLIBS) \
$(GSSAPI_LIBS) \
- $(LIBTIRPC)
+ $(LIBTIRPC) \
+ $(LIBPTHREAD)
gssd_LDFLAGS = \
$(KRBLDFLAGS)
diff --git a/utils/gssd/gssd.c b/utils/gssd/gssd.c
index 7ba27b1..43fccaf 100644
--- a/utils/gssd/gssd.c
+++ b/utils/gssd/gssd.c
@@ -87,7 +87,9 @@ unsigned int rpc_timeout = 5;
char *preferred_realm = NULL;
/* Avoid DNS reverse lookups on server names */
static bool avoid_dns = true;
-
+int thread_started = false;
+pthread_mutex_t pmutex = PTHREAD_MUTEX_INITIALIZER;
+pthread_cond_t pcond = PTHREAD_COND_INITIALIZER;
TAILQ_HEAD(topdir_list_head, topdir) topdir_list;
@@ -361,20 +363,91 @@ gssd_destroy_client(struct clnt_info *clp)
static void gssd_scan(void);
+static int
+start_upcall_thread(void (*func)(struct clnt_upcall_info *), void *info)
+{
+ pthread_attr_t attr;
+ pthread_t th;
+ int ret;
+
+ ret = pthread_attr_init(&attr);
+ if (ret != 0) {
+ printerr(0, "ERROR: failed to init pthread attr: ret %d: %s\n",
+ ret, strerror(errno));
+ return ret;
+ }
+ ret = pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
+ if (ret != 0) {
+ printerr(0, "ERROR: failed to create pthread attr: ret %d: "
+ "%s\n", ret, strerror(errno));
+ return ret;
+ }
+
+ ret = pthread_create(&th, &attr, (void *)func, (void *)info);
+ if (ret != 0)
+ printerr(0, "ERROR: pthread_create failed: ret %d: %s\n",
+ ret, strerror(errno));
+ return ret;
+}
+
+static struct clnt_upcall_info *alloc_upcall_info(struct clnt_info *clp)
+{
+ struct clnt_upcall_info *info;
+
+ info = malloc(sizeof(struct clnt_upcall_info));
+ if (info == NULL)
+ return NULL;
+ info->clp = clp;
+
+ return info;
+}
+
+/* For each upcall read the upcall info into the buffer, then create a
+ * thread in a detached state so that resources are released back into
+ * the system without the need for a join.
+ */
static void
gssd_clnt_gssd_cb(int UNUSED(fd), short UNUSED(which), void *data)
{
struct clnt_info *clp = data;
+ struct clnt_upcall_info *info;
+
+ info = alloc_upcall_info(clp);
+ if (info == NULL)
+ return;
+
+ info->lbuflen = read(clp->gssd_fd, info->lbuf, sizeof(info->lbuf));
+ if (info->lbuflen <= 0 || info->lbuf[info->lbuflen-1] != '\n') {
+ printerr(0, "WARNING: %s: failed reading request\n", __func__);
+ free(info);
+ return;
+ }
+ info->lbuf[info->lbuflen-1] = 0;
- handle_gssd_upcall(clp);
+ if (start_upcall_thread(handle_gssd_upcall, info))
+ free(info);
}
static void
gssd_clnt_krb5_cb(int UNUSED(fd), short UNUSED(which), void *data)
{
struct clnt_info *clp = data;
+ struct clnt_upcall_info *info;
+
+ info = alloc_upcall_info(clp);
+ if (info == NULL)
+ return;
+
+ if (read(clp->krb5_fd, &info->uid,
+ sizeof(info->uid)) < (ssize_t)sizeof(info->uid)) {
+ printerr(0, "WARNING: %s: failed reading uid from krb5 "
+ "upcall pipe: %s\n", __func__, strerror(errno));
+ free(info);
+ return;
+ }
- handle_krb5_upcall(clp);
+ if (start_upcall_thread(handle_krb5_upcall, info))
+ free(info);
}
static struct clnt_info *
diff --git a/utils/gssd/gssd.h b/utils/gssd/gssd.h
index c6937c5..f4f5975 100644
--- a/utils/gssd/gssd.h
+++ b/utils/gssd/gssd.h
@@ -36,6 +36,7 @@
#include <gssapi/gssapi.h>
#include <event.h>
#include <stdbool.h>
+#include <pthread.h>
#ifndef GSSD_PIPEFS_DIR
#define GSSD_PIPEFS_DIR "/var/lib/nfs/rpc_pipefs"
@@ -48,7 +49,7 @@
#define GSSD_DEFAULT_MACHINE_CRED_SUFFIX "machine"
#define GSSD_DEFAULT_KEYTAB_FILE "/etc/krb5.keytab"
#define GSSD_SERVICE_NAME "nfs"
-
+#define RPC_CHAN_BUF_SIZE 32768
/*
* The gss mechanisms that we can handle
*/
@@ -61,6 +62,10 @@ extern int root_uses_machine_creds;
extern unsigned int context_timeout;
extern unsigned int rpc_timeout;
extern char *preferred_realm;
+extern pthread_mutex_t ple_lock;
+extern pthread_cond_t pcond;
+extern pthread_mutex_t pmutex;
+extern int thread_started;
struct clnt_info {
TAILQ_ENTRY(clnt_info) list;
@@ -80,8 +85,15 @@ struct clnt_info {
struct sockaddr_storage addr;
};
-void handle_krb5_upcall(struct clnt_info *clp);
-void handle_gssd_upcall(struct clnt_info *clp);
+struct clnt_upcall_info {
+ struct clnt_info *clp;
+ char lbuf[RPC_CHAN_BUF_SIZE];
+ int lbuflen;
+ uid_t uid;
+};
+
+void handle_krb5_upcall(struct clnt_upcall_info *clp);
+void handle_gssd_upcall(struct clnt_upcall_info *clp);
#endif /* _RPC_GSSD_H_ */
diff --git a/utils/gssd/gssd_proc.c b/utils/gssd/gssd_proc.c
index 69c6a34..fda7595 100644
--- a/utils/gssd/gssd_proc.c
+++ b/utils/gssd/gssd_proc.c
@@ -69,6 +69,7 @@
#include <netdb.h>
#include <sys/types.h>
#include <sys/wait.h>
+#include <syscall.h>
#include "gssd.h"
#include "err_util.h"
@@ -442,7 +443,7 @@ change_identity(uid_t uid)
struct passwd *pw;
/* drop list of supplimentary groups first */
- if (setgroups(0, NULL) != 0) {
+ if (syscall(SYS_setgroups, 0, 0) != 0) {
printerr(0, "WARNING: unable to drop supplimentary groups!");
return errno;
}
@@ -459,20 +460,18 @@ change_identity(uid_t uid)
}
}
- /*
- * Switch the GIDs. Note that we leave the saved-set-gid alone in an
- * attempt to prevent attacks via ptrace()
+ /* Switch the UIDs and GIDs. */
+ /* For the threaded version we have to set uid,gid per thread instead
+ * of per process. glibc setresuid() when called from a thread, it'll
+ * send a signal to all other threads to synchronize the uid in all
+ * other threads. To bypass this, we have to call syscall() directly.
*/
- if (setresgid(pw->pw_gid, pw->pw_gid, -1) != 0) {
+ if (syscall(SYS_setresgid, pw->pw_gid, pw->pw_gid, pw->pw_gid) != 0) {
printerr(0, "WARNING: failed to set gid to %u!\n", pw->pw_gid);
return errno;
}
- /*
- * Switch UIDs, but leave saved-set-uid alone to prevent ptrace() by
- * other processes running with this uid.
- */
- if (setresuid(uid, uid, -1) != 0) {
+ if (syscall(SYS_setresuid, uid, uid, uid) != 0) {
printerr(0, "WARNING: Failed to setuid for user with uid %u\n",
uid);
return errno;
@@ -554,7 +553,15 @@ krb5_use_machine_creds(struct clnt_info *clp, uid_t uid, char *tgtname,
goto out;
}
for (ccname = credlist; ccname && *ccname; ccname++) {
- gssd_setup_krb5_machine_gss_ccache(*ccname);
+ u_int min_stat;
+
+ if (gss_krb5_ccache_name(&min_stat, *ccname, NULL) !=
+ GSS_S_COMPLETE) {
+ printerr(1, "WARNING: gss_krb5_ccache_name "
+ "with name '%s' failed (%s)\n",
+ *ccname, error_message(min_stat));
+ continue;
+ }
if ((create_auth_rpc_client(clp, tgtname, rpc_clnt,
&auth, uid,
AUTHTYPE_KRB5,
@@ -602,7 +609,6 @@ process_krb5_upcall(struct clnt_info *clp, uid_t uid, int fd, char *tgtname,
gss_buffer_desc token;
int err, downcall_err = -EACCES;
OM_uint32 maj_stat, min_stat, lifetime_rec;
- pid_t pid, childpid = -1;
gss_name_t gacceptor = GSS_C_NO_NAME;
gss_OID mech;
gss_buffer_desc acceptor = {0};
@@ -635,36 +641,6 @@ process_krb5_upcall(struct clnt_info *clp, uid_t uid, int fd, char *tgtname,
if (uid != 0 || (uid == 0 && root_uses_machine_creds == 0 &&
service == NULL)) {
- /* already running as uid 0 */
- if (uid == 0)
- goto no_fork;
-
- pid = fork();
- switch(pid) {
- case 0:
- /* Child: fall through to rest of function */
- childpid = getpid();
- unsetenv("KRB5CCNAME");
- printerr(2, "CHILD forked pid %d \n", childpid);
- break;
- case -1:
- /* fork() failed! */
- printerr(0, "WARNING: unable to fork() to handle"
- "upcall: %s\n", strerror(errno));
- return;
- default:
- /* Parent: just wait on child to exit and return */
- do {
- pid = wait(&err);
- } while(pid == -1 && errno != -ECHILD);
-
- if (WIFSIGNALED(err))
- printerr(0, "WARNING: forked child was killed"
- "with signal %d\n", WTERMSIG(err));
- return;
- }
-no_fork:
-
auth = krb5_not_machine_creds(clp, uid, tgtname, &downcall_err,
&err, &rpc_clnt);
if (err)
@@ -730,11 +706,7 @@ out:
if (rpc_clnt)
clnt_destroy(rpc_clnt);
- pid = getpid();
- if (pid == childpid)
- exit(0);
- else
- return;
+ return;
out_return_error:
do_error_downcall(fd, uid, downcall_err);
@@ -742,27 +714,21 @@ out_return_error:
}
void
-handle_krb5_upcall(struct clnt_info *clp)
+handle_krb5_upcall(struct clnt_upcall_info *info)
{
- uid_t uid;
-
- if (read(clp->krb5_fd, &uid, sizeof(uid)) < (ssize_t)sizeof(uid)) {
- printerr(0, "WARNING: failed reading uid from krb5 "
- "upcall pipe: %s\n", strerror(errno));
- return;
- }
+ struct clnt_info *clp = info->clp;
- printerr(2, "\n%s: uid %d (%s)\n", __func__, uid, clp->relpath);
+ printerr(2, "\n%s: uid %d (%s)\n", __func__, info->uid, clp->relpath);
- process_krb5_upcall(clp, uid, clp->krb5_fd, NULL, NULL);
+ process_krb5_upcall(clp, info->uid, clp->krb5_fd, NULL, NULL);
+ free(info);
}
void
-handle_gssd_upcall(struct clnt_info *clp)
+handle_gssd_upcall(struct clnt_upcall_info *info)
{
+ struct clnt_info *clp = info->clp;
uid_t uid;
- char *lbuf = NULL;
- int lbuflen = 0;
char *p;
char *mech = NULL;
char *uidstr = NULL;
@@ -770,15 +736,9 @@ handle_gssd_upcall(struct clnt_info *clp)
char *service = NULL;
char *enctypes = NULL;
- if (readline(clp->gssd_fd, &lbuf, &lbuflen) != 1) {
- printerr(0, "WARNING: handle_gssd_upcall: "
- "failed reading request\n");
- return;
- }
-
- printerr(2, "\n%s: '%s' (%s)\n", __func__, lbuf, clp->relpath);
+ printerr(2, "\n%s: '%s' (%s)\n", __func__, info->lbuf, clp->relpath);
- for (p = strtok(lbuf, " "); p; p = strtok(NULL, " ")) {
+ for (p = strtok(info->lbuf, " "); p; p = strtok(NULL, " ")) {
if (!strncmp(p, "mech=", strlen("mech=")))
mech = p + strlen("mech=");
else if (!strncmp(p, "uid=", strlen("uid=")))
@@ -794,8 +754,8 @@ handle_gssd_upcall(struct clnt_info *clp)
if (!mech || strlen(mech) < 1) {
printerr(0, "WARNING: handle_gssd_upcall: "
"failed to find gss mechanism name "
- "in upcall string '%s'\n", lbuf);
- return;
+ "in upcall string '%s'\n", info->lbuf);
+ goto out;
}
if (uidstr) {
@@ -807,21 +767,21 @@ handle_gssd_upcall(struct clnt_info *clp)
if (!uidstr) {
printerr(0, "WARNING: handle_gssd_upcall: "
"failed to find uid "
- "in upcall string '%s'\n", lbuf);
- return;
+ "in upcall string '%s'\n", info->lbuf);
+ goto out;
}
if (enctypes && parse_enctypes(enctypes) != 0) {
printerr(0, "WARNING: handle_gssd_upcall: "
"parsing encryption types failed: errno %d\n", errno);
- return;
+ goto out;
}
if (target && strlen(target) < 1) {
printerr(0, "WARNING: handle_gssd_upcall: "
"failed to parse target name "
- "in upcall string '%s'\n", lbuf);
- return;
+ "in upcall string '%s'\n", info->lbuf);
+ goto out;
}
/*
@@ -835,8 +795,8 @@ handle_gssd_upcall(struct clnt_info *clp)
if (service && strlen(service) < 1) {
printerr(0, "WARNING: handle_gssd_upcall: "
"failed to parse service type "
- "in upcall string '%s'\n", lbuf);
- return;
+ "in upcall string '%s'\n", info->lbuf);
+ goto out;
}
if (strcmp(mech, "krb5") == 0 && clp->servername)
@@ -847,5 +807,8 @@ handle_gssd_upcall(struct clnt_info *clp)
"received unknown gss mech '%s'\n", mech);
do_error_downcall(clp->gssd_fd, uid, -EACCES);
}
+out:
+ free(info);
+ return;
}
diff --git a/utils/gssd/krb5_util.c b/utils/gssd/krb5_util.c
index 3849b6a..bc29787 100644
--- a/utils/gssd/krb5_util.c
+++ b/utils/gssd/krb5_util.c
@@ -128,6 +128,7 @@
/* Global list of principals/cache file names for machine credentials */
struct gssd_k5_kt_princ *gssd_k5_kt_princ_list = NULL;
+pthread_mutex_t ple_lock = PTHREAD_MUTEX_INITIALIZER;
#ifdef HAVE_SET_ALLOWABLE_ENCTYPES
int limit_to_legacy_enctypes = 0;
@@ -467,37 +468,6 @@ gssd_get_single_krb5_cred(krb5_context context,
}
/*
- * Depending on the version of Kerberos, we either need to use
- * a private function, or simply set the environment variable.
- */
-static void
-gssd_set_krb5_ccache_name(char *ccname)
-{
-#ifdef USE_GSS_KRB5_CCACHE_NAME
- u_int maj_stat, min_stat;
-
- printerr(3, "using gss_krb5_ccache_name to select krb5 ccache %s\n",
- ccname);
- maj_stat = gss_krb5_ccache_name(&min_stat, ccname, NULL);
- if (maj_stat != GSS_S_COMPLETE) {
- printerr(0, "WARNING: gss_krb5_ccache_name with "
- "name '%s' failed (%s)\n",
- ccname, error_message(min_stat));
- }
-#else
- /*
- * Set the KRB5CCNAME environment variable to tell the krb5 code
- * which credentials cache to use. (Instead of using the private
- * function above for which there is no generic gssapi
- * equivalent.)
- */
- printerr(3, "using environment variable to select krb5 ccache %s\n",
- ccname);
- setenv("KRB5CCNAME", ccname, 1);
-#endif
-}
-
-/*
* Given a principal, find a matching ple structure
*/
static struct gssd_k5_kt_princ *
@@ -586,10 +556,12 @@ get_ple_by_princ(krb5_context context, krb5_principal princ)
/* Need to serialize list if we ever become multi-threaded! */
+ pthread_mutex_lock(&ple_lock);
ple = find_ple_by_princ(context, princ);
if (ple == NULL) {
ple = new_ple(context, princ);
}
+ pthread_mutex_unlock(&ple_lock);
return ple;
}
@@ -1091,6 +1063,7 @@ gssd_setup_krb5_user_gss_ccache(uid_t uid, char *servername, char *dirpattern)
const char *cctype;
struct dirent *d;
int err, i, j;
+ u_int maj_stat, min_stat;
printerr(3, "looking for client creds with uid %u for "
"server %s in %s\n", uid, servername, dirpattern);
@@ -1126,22 +1099,16 @@ gssd_setup_krb5_user_gss_ccache(uid_t uid, char *servername, char *dirpattern)
printerr(2, "using %s as credentials cache for client with "
"uid %u for server %s\n", buf, uid, servername);
- gssd_set_krb5_ccache_name(buf);
- return 0;
-}
-/*
- * Let the gss code know where to find the machine credentials ccache.
- *
- * Returns:
- * void
- */
-void
-gssd_setup_krb5_machine_gss_ccache(char *ccname)
-{
- printerr(2, "using %s as credentials cache for machine creds\n",
- ccname);
- gssd_set_krb5_ccache_name(ccname);
+ printerr(3, "using gss_krb5_ccache_name to select krb5 ccache %s\n",
+ buf);
+ maj_stat = gss_krb5_ccache_name(&min_stat, buf, NULL);
+ if (maj_stat != GSS_S_COMPLETE) {
+ printerr(0, "ERROR: unable to get user cred cache '%s' "
+ "failed (%s)\n", buf, error_message(min_stat));
+ return maj_stat;
+ }
+ return 0;
}
/*
diff --git a/utils/gssd/krb5_util.h b/utils/gssd/krb5_util.h
index a319588..e3bbb07 100644
--- a/utils/gssd/krb5_util.h
+++ b/utils/gssd/krb5_util.h
@@ -27,7 +27,6 @@ int gssd_setup_krb5_user_gss_ccache(uid_t uid, char *servername,
char *dirname);
int gssd_get_krb5_machine_cred_list(char ***list);
void gssd_free_krb5_machine_cred_list(char **list);
-void gssd_setup_krb5_machine_gss_ccache(char *servername);
void gssd_destroy_krb5_machine_creds(void);
int gssd_refresh_krb5_machine_credential(char *hostname,
struct gssd_k5_kt_princ *ple,
@@ -55,8 +54,6 @@ int limit_krb5_enctypes(struct rpc_gss_sec *sec);
#define k5_free_unparsed_name(ctx, name) free(name)
#define k5_free_default_realm(ctx, realm) free(realm)
#define k5_free_kt_entry(ctx, kte) krb5_kt_free_entry((ctx),(kte))
-#undef USE_GSS_KRB5_CCACHE_NAME
-#define USE_GSS_KRB5_CCACHE_NAME 1
#endif
#endif /* KRB5_UTIL_H */