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diff -up bind-9.5.0b3/bin/named/unix/os.c.libcap bind-9.5.0b3/bin/named/unix/os.c
--- bind-9.5.0b3/bin/named/unix/os.c.libcap 2008-01-30 05:55:51.000000000 +0100
+++ bind-9.5.0b3/bin/named/unix/os.c 2008-05-05 10:56:00.000000000 +0200
@@ -69,7 +69,7 @@ static int devnullfd = -1;
/*
* Linux defines:
* (T) HAVE_LINUXTHREADS
- * (C) HAVE_LINUX_CAPABILITY_H
+ * (C) HAVE_SYS_CAPABILITY_H (or HAVE_LINUX_CAPABILITY_H)
* (P) HAVE_SYS_PRCTL_H
* The possible cases are:
* none: setuid() normally
@@ -116,16 +116,9 @@ static int dfd[2] = { -1, -1 };
static isc_boolean_t non_root = ISC_FALSE;
static isc_boolean_t non_root_caps = ISC_FALSE;
-#if defined(HAVE_CAPSET)
-#undef _POSIX_SOURCE
#ifdef HAVE_SYS_CAPABILITY_H
#include <sys/capability.h>
#else
-#include <linux/capability.h>
-int capset(cap_user_header_t hdrp, const cap_user_data_t datap);
-#endif
-#include <sys/prctl.h>
-#else
/*%
* We define _LINUX_FS_H to prevent it from being included. We don't need
* anything from it, and the files it includes cause warnings with 2.2
@@ -133,9 +126,20 @@ int capset(cap_user_header_t hdrp, const
* and <string.h>) on 2.3 kernels.
*/
#define _LINUX_FS_H
-
-#include <sys/syscall.h> /* Required for syscall(). */
-#include <linux/capability.h> /* Required for _LINUX_CAPABILITY_VERSION. */
+#include <linux/capability.h>
+#ifdef HAVE_CAPSET
+int capset(cap_user_header_t hdrp, const cap_user_data_t datap);
+#else
+/* We don't have libcap or capset, let's use syscall*/
+#include <syscall.h>
+#ifndef SYS_capset
+#ifndef __NR_capset
+#include <asm/unistd.h> /* Slackware 4.0 needs this. */
+#endif /* __NR_capset */
+#define SYS_capset __NR_capset
+#endif /* SYS_capset */
+#endif /* HAVE_CAPSET */
+#endif /* HAVE_SYS_CAPABILITY_H */
#ifdef HAVE_SYS_PRCTL_H
#include <sys/prctl.h> /* Required for prctl(). */
@@ -152,23 +156,28 @@ int capset(cap_user_header_t hdrp, const
#endif /* HAVE_SYS_PRCTL_H */
-#ifndef SYS_capset
-#ifndef __NR_capset
-#include <asm/unistd.h> /* Slackware 4.0 needs this. */
-#endif
-#define SYS_capset __NR_capset
-#endif
-#endif
+#ifdef HAVE_LIBCAP
+#define SETCAPS_FUNC "cap_set_proc "
+#else
+typedef unsigned int cap_t;
+#ifdef HAVE_CAPSET
+#define SETCAPS_FUNC "capset "
+#else
+#define SETCAPS_FUNC "syscall(capset) "
+#endif /* HAVE_CAPSET */
+#endif /* HAVE_LIBCAP */
static void
-linux_setcaps(unsigned int caps) {
+linux_setcaps(cap_t caps) {
+#ifndef HAVE_LIBCAP
struct __user_cap_header_struct caphead;
struct __user_cap_data_struct cap;
+#endif
char strbuf[ISC_STRERRORSIZE];
if ((getuid() != 0 && !non_root_caps) || non_root)
return;
-
+#ifndef HAVE_LIBCAP
memset(&caphead, 0, sizeof(caphead));
caphead.version = _LINUX_CAPABILITY_VERSION;
caphead.pid = 0;
@@ -176,46 +185,76 @@ linux_setcaps(unsigned int caps) {
cap.effective = caps;
cap.permitted = caps;
cap.inheritable = 0;
-#ifdef HAVE_CAPSET
+#endif
+#ifdef HAVE_LIBCAP
+ if (cap_set_proc(caps) < 0) {
+#elif defined(HAVE_CAPSET)
if (capset(&caphead, &cap) < 0 ) {
- isc__strerror(errno, strbuf, sizeof(strbuf));
- ns_main_earlyfatal("capset failed: %s:"
- " please ensure that the capset kernel"
- " module is loaded. see insmod(8)",
- strbuf);
- }
#else
if (syscall(SYS_capset, &caphead, &cap) < 0) {
+#endif
isc__strerror(errno, strbuf, sizeof(strbuf));
- ns_main_earlyfatal("syscall(capset) failed: %s:"
+ ns_main_earlyfatal(SETCAPS_FUNC "failed: %s:"
" please ensure that the capset kernel"
" module is loaded. see insmod(8)",
strbuf);
}
-#endif
}
+#ifdef HAVE_LIBCAP
+#define SET_CAP(flag) \
+ do { \
+ capval = (flag); \
+ err = cap_set_flag(caps, CAP_EFFECTIVE, 1, &capval, CAP_SET); \
+ if (err == -1) { \
+ isc__strerror(errno, strbuf, sizeof(strbuf)); \
+ ns_main_earlyfatal("cap_set_proc failed: %s", strbuf); \
+ } \
+ \
+ err = cap_set_flag(caps, CAP_PERMITTED, 1, &capval, CAP_SET); \
+ if (err == -1) { \
+ isc__strerror(errno, strbuf, sizeof(strbuf)); \
+ ns_main_earlyfatal("cap_set_proc failed: %s", strbuf); \
+ } \
+ } while (0)
+#define INIT_CAP \
+ do { \
+ caps = cap_init(); \
+ if (caps == NULL) { \
+ isc__strerror(errno, strbuf, sizeof(strbuf)); \
+ ns_main_earlyfatal("cap_init failed: %s", strbuf); \
+ } \
+ } while (0)
+#else
+#define SET_CAP(flag) { caps |= (1 << (flag)); }
+#define INIT_CAP { caps = 0; }
+#endif /* HAVE_LIBCAP */
+
static void
linux_initialprivs(void) {
- unsigned int caps;
+ cap_t caps;
+#ifdef HAVE_LIBCAP
+ cap_value_t capval;
+ char strbuf[ISC_STRERRORSIZE];
+ int err;
+#endif
/*%
* We don't need most privileges, so we drop them right away.
* Later on linux_minprivs() will be called, which will drop our
* capabilities to the minimum needed to run the server.
*/
-
- caps = 0;
+ INIT_CAP;
/*
* We need to be able to bind() to privileged ports, notably port 53!
*/
- caps |= (1 << CAP_NET_BIND_SERVICE);
+ SET_CAP(CAP_NET_BIND_SERVICE);
/*
* We need chroot() initially too.
*/
- caps |= (1 << CAP_SYS_CHROOT);
+ SET_CAP(CAP_SYS_CHROOT);
#if defined(HAVE_SYS_PRCTL_H) || !defined(HAVE_LINUXTHREADS)
/*
@@ -224,19 +263,19 @@ linux_initialprivs(void) {
* tried) or we're not using threads. If either of these is
* true, we want the setuid capability.
*/
- caps |= (1 << CAP_SETUID);
+ SET_CAP(CAP_SETUID);
#endif
/*
* Since we call initgroups, we need this.
*/
- caps |= (1 << CAP_SETGID);
+ SET_CAP(CAP_SETGID);
/*
* Without this, we run into problems reading a configuration file
* owned by a non-root user and non-world-readable on startup.
*/
- caps |= (1 << CAP_DAC_READ_SEARCH);
+ SET_CAP(CAP_DAC_READ_SEARCH);
/*
* XXX We might want to add CAP_SYS_RESOURCE, though it's not
@@ -245,15 +284,21 @@ linux_initialprivs(void) {
* of files, the stack size, data size, and core dump size to
* support named.conf options, this is now being added to test.
*/
- caps |= (1 << CAP_SYS_RESOURCE);
+ SET_CAP(CAP_SYS_RESOURCE);
linux_setcaps(caps);
}
static void
linux_minprivs(void) {
- unsigned int caps;
+ cap_t caps;
+#ifdef HAVE_LIBCAP
+ cap_value_t capval;
+ char strbuf[ISC_STRERRORSIZE];
+ int err;
+#endif
+ INIT_CAP;
/*%
* Drop all privileges except the ability to bind() to privileged
* ports.
@@ -262,8 +307,7 @@ linux_minprivs(void) {
* chroot() could be used to escape from the chrooted area.
*/
- caps = 0;
- caps |= (1 << CAP_NET_BIND_SERVICE);
+ SET_CAP(CAP_NET_BIND_SERVICE);
/*
* XXX We might want to add CAP_SYS_RESOURCE, though it's not
@@ -272,7 +316,7 @@ linux_minprivs(void) {
* of files, the stack size, data size, and core dump size to
* support named.conf options, this is now being added to test.
*/
- caps |= (1 << CAP_SYS_RESOURCE);
+ SET_CAP(CAP_SYS_RESOURCE);
linux_setcaps(caps);
}
diff -up bind-9.5.0b3/configure.in.libcap bind-9.5.0b3/configure.in
--- bind-9.5.0b3/configure.in.libcap 2008-01-30 05:55:51.000000000 +0100
+++ bind-9.5.0b3/configure.in 2008-05-05 10:53:11.000000000 +0200
@@ -1876,6 +1876,7 @@ AC_ARG_ENABLE(linux-caps,
case "$enable_linux_caps" in
yes|'')
AC_CHECK_HEADERS(linux/capability.h sys/capability.h)
+ AC_CHECK_LIB(cap, cap_set_proc)
AC_CHECK_FUNCS(capset)
;;
no)
|
