Use aux vector to get values for SSP canary, pagesize, pagesizes array,

number of host CPUs and osreldate.

This eliminates the last sysctl(2) calls from the dynamically linked image
startup.

No objections from:	kan
Tested by:	marius (sparc64)
MFC after:	1 month

lib/libc/gen/Makefile.inc

@@ -7,7 +7,7 @@
 SRCS+=  __getosreldate.c __xuname.c \
 	_once_stub.c _pthread_stubs.c _rand48.c _spinlock_stub.c \
 	_thread_init.c \
-	alarm.c arc4random.c assert.c basename.c check_utility_compat.c \
+	alarm.c arc4random.c assert.c aux.c basename.c check_utility_compat.c \
 	clock.c closedir.c confstr.c \
 	crypt.c ctermid.c daemon.c devname.c dirname.c disklabel.c \
 	dlfcn.c drand48.c erand48.c err.c errlst.c errno.c \

lib/libc/gen/Symbol.map

@@ -492,4 +492,6 @@ FBSDprivate_1.0 {
 	_libc_sem_timedwait_compat;
 	_libc_sem_post_compat;
 	_libc_sem_getvalue_compat;
+
+	__elf_aux_vector;
 };

lib/libc/gen/__getosreldate.c

@@ -29,6 +29,9 @@ __FBSDID("$FreeBSD$");
 
 #include <sys/param.h>
 #include <sys/sysctl.h>
+#include <errno.h>
+#include <link.h>
+#include "libc_private.h"
 
 int __getosreldate(void);
 
@@ -51,7 +54,11 @@ __getosreldate(void)
 
 	if (osreldate != 0)
 		return (osreldate);
-	
+
+	error = _elf_aux_info(AT_OSRELDATE, &osreldate, sizeof(osreldate));
+	if (error == 0 && osreldate != 0)
+		return (osreldate);
+
 	oid[0] = CTL_KERN;
 	oid[1] = KERN_OSRELDATE;
 	osrel = 0;

lib/libc/gen/aux.c

@@ -0,0 +1,146 @@
+/*-
+ * Copyright 2010 Konstantin Belousov <kib@FreeBSD.ORG>.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include "namespace.h"
+#include <elf.h>
+#include <errno.h>
+#include <link.h>
+#include <pthread.h>
+#include <string.h>
+#include "un-namespace.h"
+#include "libc_private.h"
+
+Elf_Auxinfo *__elf_aux_vector;
+
+static pthread_once_t aux_once = PTHREAD_ONCE_INIT;
+
+static int pagesize, osreldate, canary_len, ncpus, pagesizes_len;
+static char *canary, *pagesizes;
+
+static void
+init_aux(void)
+{
+	Elf_Auxinfo *aux;
+
+	for (aux = __elf_aux_vector; aux->a_type != AT_NULL; aux++) {
+		switch (aux->a_type) {
+		case AT_CANARY:
+			canary = (char *)(aux->a_un.a_ptr);
+			break;
+
+		case AT_CANARYLEN:
+			canary_len = aux->a_un.a_val;
+			break;
+
+		case AT_PAGESIZES:
+			pagesizes = (char *)(aux->a_un.a_ptr);
+			break;
+
+		case AT_PAGESIZESLEN:
+			pagesizes_len = aux->a_un.a_val;
+			break;
+
+		case AT_PAGESZ:
+			pagesize = aux->a_un.a_val;
+			break;
+
+		case AT_OSRELDATE:
+			osreldate = aux->a_un.a_val;
+			break;
+
+		case AT_NCPUS:
+			ncpus = aux->a_un.a_val;
+			break;
+		}
+	}
+}
+
+int
+_elf_aux_info(int aux, void *buf, int buflen)
+{
+	int res;
+
+	if (__elf_aux_vector == NULL)
+		return (ENOSYS);
+	_once(&aux_once, init_aux);
+
+	switch (aux) {
+	case AT_CANARY:
+		if (canary != NULL && canary_len >= buflen) {
+			memcpy(buf, canary, buflen);
+			memset(canary, 0, canary_len);
+			canary = NULL;
+			res = 0;
+		} else
+			res = ENOENT;
+		break;
+	case AT_PAGESIZES:
+		if (pagesizes != NULL && pagesizes_len >= buflen) {
+			memcpy(buf, pagesizes, buflen);
+			res = 0;
+		} else
+			res = ENOENT;
+		break;
+
+	case AT_PAGESZ:
+		if (buflen == sizeof(int)) {
+			if (pagesize != 0) {
+				*(int *)buf = pagesize;
+				res = 0;
+			} else
+				res = ENOENT;
+		} else
+			res = EINVAL;
+		break;
+	case AT_OSRELDATE:
+		if (buflen == sizeof(int)) {
+			if (osreldate != 0) {
+				*(int *)buf = osreldate;
+				res = 0;
+			} else
+				res = ENOENT;
+		} else
+			res = EINVAL;
+		break;
+	case AT_NCPUS:
+		if (buflen == sizeof(int)) {
+			if (ncpus != 0) {
+				*(int *)buf = ncpus;
+				res = 0;
+			} else
+				res = ENOENT;
+		} else
+			res = EINVAL;
+		break;
+	default:
+		res = ENOENT;
+		break;
+	}
+	return (res);
+}

lib/libc/gen/getosreldate.c

@@ -35,6 +35,7 @@ __FBSDID("$FreeBSD$");
 
 #include <sys/param.h>
 #include <sys/sysctl.h>
+#include <errno.h>
 #include <stdlib.h>
 
 #include <osreldate.h>
@@ -45,15 +46,17 @@ getosreldate(void)
 	int mib[2];
 	size_t size;
 	int value;
-
 	char *temp;
 
+	if ((temp = getenv("OSVERSION"))) {
+		value = atoi(temp);
+		return (value);
+	}
+
 	mib[0] = CTL_KERN;
 	mib[1] = KERN_OSRELDATE;
 	size = sizeof value;
 	if (sysctl(mib, 2, &value, &size, NULL, 0) == -1)
 		return (-1);
-	if ((temp = getenv("OSVERSION")))
-		value = atoi(temp);
 	return (value);
 }

lib/libc/gen/getpagesize.c

@@ -36,8 +36,12 @@ __FBSDID("$FreeBSD$");
 #include <sys/param.h>
 #include <sys/sysctl.h>
 
+#include <errno.h>
+#include <link.h>
 #include <unistd.h>
 
+#include "libc_private.h"
+
 /*
  * This is unlikely to change over the running time of any
  * program, so we cache the result to save some syscalls.
@@ -52,13 +56,20 @@ getpagesize()
 	int mib[2]; 
 	static int value;
 	size_t size;
+	int error;
+
+	if (value != 0)
+		return (value);
+
+	error = _elf_aux_info(AT_PAGESZ, &value, sizeof(value));
+	if (error == 0 && value != 0)
+		return (value);
+
+	mib[0] = CTL_HW;
+	mib[1] = HW_PAGESIZE;
+	size = sizeof value;
+	if (sysctl(mib, 2, &value, &size, NULL, 0) == -1)
+		return (-1);
 
-	if (!value) {
-		mib[0] = CTL_HW;
-		mib[1] = HW_PAGESIZE;
-		size = sizeof value;
-		if (sysctl(mib, 2, &value, &size, NULL, 0) == -1)
-			return (-1);
-	}
 	return (value);
 }

lib/libc/gen/getpagesizes.c

@@ -32,6 +32,9 @@ __FBSDID("$FreeBSD$");
 #include <sys/sysctl.h>
 
 #include <errno.h>
+#include <link.h>
+
+#include "libc_private.h"
 
 /*
  * Retrieves page size information from the system.  Specifically, returns the
@@ -51,7 +54,7 @@ getpagesizes(size_t pagesize[], int nelem)
 	static u_long ps[MAXPAGESIZES];
 	static int nops;
 	size_t size;
-	int i; 
+	int error, i;
 
 	if (nelem < 0 || (nelem > 0 && pagesize == NULL)) {
 		errno = EINVAL;
@@ -59,9 +62,13 @@ getpagesizes(size_t pagesize[], int nelem)
 	}
 	/* Cache the result of the sysctl(2). */
 	if (nops == 0) {
+		error = _elf_aux_info(AT_PAGESIZES, ps, sizeof(ps));
 		size = sizeof(ps);
-		if (sysctlbyname("hw.pagesizes", ps, &size, NULL, 0) == -1)
-			return (-1);
+		if (error != 0 || ps[0] == 0) {
+			if (sysctlbyname("hw.pagesizes", ps, &size, NULL, 0)
+			    == -1)
+				return (-1);
+		}
 		/* Count the number of page sizes that are supported. */
 		nops = size / sizeof(ps[0]);
 		while (nops > 0 && ps[nops - 1] == 0)

lib/libc/include/libc_private.h

@@ -213,4 +213,6 @@ extern int	__sys_fcntl(int, int, ...);
 /* execve() with PATH processing to implement posix_spawnp() */
 int _execvpe(const char *, char * const *, char * const *);
 
+int _elf_aux_info(int aux, void *buf, int buflen);
+
 #endif /* _LIBC_PRIVATE_H_ */

lib/libc/stdlib/malloc.c

@@ -180,6 +180,7 @@ __FBSDID("$FreeBSD$");
 
 #include <errno.h>
 #include <limits.h>
+#include <link.h>
 #include <pthread.h>
 #include <sched.h>
 #include <stdarg.h>
@@ -194,6 +195,8 @@ __FBSDID("$FreeBSD$");
 
 #include "un-namespace.h"
 
+#include "libc_private.h"
+
 #define	RB_COMPACT
 #include "rb.h"
 #if (defined(MALLOC_TCACHE) && defined(MALLOC_STATS))
@@ -5353,14 +5356,20 @@ small_size2bin_init_hard(void)
 static unsigned
 malloc_ncpus(void)
 {
+	int mib[2];
 	unsigned ret;
-	size_t retlen = sizeof(ret);
-	int mib[] = {CTL_HW, HW_NCPU};
+	int error;
+	size_t len;
 
-	if (sysctl(mib, sizeof(mib) / sizeof(int), &ret, &retlen,
-	    (void *)0, 0) == -1) {
-		/* Error. */
-		ret = 1;
+	error = _elf_aux_info(AT_NCPUS, &ret, sizeof(ret));
+	if (error != 0 || ret == 0) {
+		mib[0] = CTL_HW;
+		mib[1] = HW_NCPU;
+		len = sizeof(ret);
+		if (sysctl(mib, 2, &ret, &len, (void *)NULL, 0) == -1) {
+			/* Error. */
+			ret = 1;
+		}
 	}
 
 	return (ret);

lib/libc/sys/stack_protector.c

@@ -34,10 +34,13 @@ __FBSDID("$FreeBSD$");
 #include <sys/param.h>
 #include <sys/sysctl.h>
 #include <sys/types.h>
+#include <errno.h>
+#include <link.h>
 #include <signal.h>
 #include <string.h>
 #include <syslog.h>
 #include <unistd.h>
+#include "libc_private.h"
 
 extern int __sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp,
     void *newp, size_t newlen);
@@ -54,9 +57,14 @@ __guard_setup(void)
 {
 	int mib[2];
 	size_t len;
+	int error;
 
 	if (__stack_chk_guard[0] != 0)
 		return;
+	error = _elf_aux_info(AT_CANARY, __stack_chk_guard,
+	    sizeof(__stack_chk_guard));
+	if (error == 0 && __stack_chk_guard[0] != 0)
+		return;
 
 	mib[0] = CTL_KERN;
 	mib[1] = KERN_ARND;