Prepare for an upcoming ELF executable change. This will allow ld.so to

protect the GOT and PLT sections of the executable from being overwritten.
This behavior is enabled by changes in the executable/shared object layout,
and does not occur without the ld changes.

16 files changed, 443 insertions, 16 deletions

diff --git a/libexec/ld.so/alpha/ldasm.S b/libexec/ld.so/alpha/ldasm.S
index 68659b6e05e..c6917ff2e26 100644
--- a/libexec/ld.so/alpha/ldasm.S
+++ b/libexec/ld.so/alpha/ldasm.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ldasm.S,v 1.10 2002/10/21 16:01:55 drahn Exp $ */
+/*	$OpenBSD: ldasm.S,v 1.11 2002/12/18 19:20:01 drahn Exp $ */
 
 /*
  * Copyright (c) 2001 Niklas Hallqvist
@@ -290,3 +290,16 @@ LEAF_NOPROFILE(_dl_getdirentries, 4)
 	call_pal PAL_OSF1_callsys
 	RET
 END(_dl_getdirentries)
+
+/* _dl_sigprocmask does not support NULL new mask */
+LEAF_NOPROFILE(_dl_sigprocmask, 4)
+	mov	a2, a5
+	ldl     a1, 0(a1)               /* load the set from *set */
+	ldiq	v0, SYS_sigprocmask
+	call_pal PAL_OSF1_callsys
+	/* What about syscalls failing? */
+	beq	a5, 1f
+	stl	v0, 0(a5)
+1:	mov	zero, v0
+	RET
+END(_dl_sigprocmask)
diff --git a/libexec/ld.so/alpha/rtld_machine.c b/libexec/ld.so/alpha/rtld_machine.c
index 0c10637104d..cde1b9e0b5a 100644
--- a/libexec/ld.so/alpha/rtld_machine.c
+++ b/libexec/ld.so/alpha/rtld_machine.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: rtld_machine.c,v 1.17 2002/11/14 15:15:54 drahn Exp $ */
+/*	$OpenBSD: rtld_machine.c,v 1.18 2002/12/18 19:20:01 drahn Exp $ */
 
 /*
  * Copyright (c) 1999 Dale Rahn
@@ -44,6 +44,7 @@
 
 #include <nlist.h>
 #include <link.h>
+#include <signal.h>
 
 #include "syscall.h"
 #include "archdep.h"
@@ -189,6 +190,7 @@ _dl_bind(elf_object_t *object, Elf_Word reloff)
 	Elf_Addr *addr, ooff;
 	const Elf_Sym *sym, *this;
 	const char *symn;
+	sigset_t omask, nmask;
 
 	rela = (Elf_RelA *)(object->Dyn.info[DT_JMPREL] + reloff);
 
@@ -205,7 +207,23 @@ _dl_bind(elf_object_t *object, Elf_Word reloff)
 		_dl_printf("lazy binding failed!\n");
 		*((int *)0) = 0;	/* XXX */
 	}
+	/* if PLT is protected, allow the write */
+	if (object->plt_addr != NULL && object->plt_size != 0) {
+		sigfillset(&nmask);
+		_dl_sigprocmask(SIG_BLOCK, &nmask, &omask);
+		_dl_mprotect(addr, sizeof(Elf_Addr),
+		    PROT_READ|PROT_WRITE|PROT_EXEC); 
+	}
+
 	*addr = ooff + this->st_value + rela->r_addend;
+
+	/* if PLT is (to be protected, change back to RO/X  */
+	if (object->plt_addr != NULL && object->plt_size != 0) {
+		_dl_mprotect(addr, sizeof(Elf_Addr),
+		    PROT_READ|PROT_EXEC);
+		_dl_sigprocmask(SIG_SETMASK, &omask, NULL);
+	}
+
 	return (void *)*addr;
 }
 
@@ -217,9 +235,40 @@ _dl_md_reloc_got(elf_object_t *object, int lazy)
 {
 	Elf_Addr *pltgot;
 	extern void _dl_bind_start(void);	/* XXX */
+	Elf_Addr ooff;
+	const Elf_Sym *this;
+
 
 	pltgot = (Elf_Addr *)object->Dyn.info[DT_PLTGOT];
 
+	this = NULL;
+	ooff = _dl_find_symbol("__got_start", object, &this,
+	    SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT,
+	    NULL);
+	if (this != NULL)
+		object->got_addr = ooff + this->st_value;
+ 
+	this = NULL;
+	ooff = _dl_find_symbol("__got_end", object, &this,
+	    SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT,
+	    NULL);
+	if (this != NULL)
+		object->got_size = ooff + this->st_value  - object->got_addr;
+ 
+	this = NULL;
+	ooff = _dl_find_symbol("__plt_start", object, &this,
+	    SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT,
+	    NULL);
+	if (this != NULL)
+		object->plt_addr = ooff + this->st_value;
+	 
+	this = NULL;
+	ooff = _dl_find_symbol("__plt_end", object, &this,
+	    SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT,
+	    NULL);
+	if (this != NULL)
+		object->plt_size = ooff + this->st_value  - object->plt_addr;
+
 	if (object->obj_type == OBJTYPE_LDR || !lazy || pltgot == NULL) {
 		_dl_md_reloc(object, DT_JMPREL, DT_PLTRELSZ);
 		return;
@@ -241,4 +290,10 @@ _dl_md_reloc_got(elf_object_t *object, int lazy)
 
 	pltgot[2] = (Elf_Addr)_dl_bind_start;
 	pltgot[3] = (Elf_Addr)object;
+	if (object->got_addr != NULL && object->got_size != 0) 
+		_dl_mprotect((void*)object->got_addr, object->got_size,
+		    PROT_READ|PROT_EXEC);
+	if (object->plt_addr != NULL && object->got_size != 0) 
+		_dl_mprotect((void*)object->plt_addr, object->plt_size,
+		    PROT_READ|PROT_EXEC);
 }
diff --git a/libexec/ld.so/alpha/syscall.h b/libexec/ld.so/alpha/syscall.h
index 6c65a0b9f81..11d2c9692f3 100644
--- a/libexec/ld.so/alpha/syscall.h
+++ b/libexec/ld.so/alpha/syscall.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: syscall.h,v 1.9 2002/07/24 04:11:10 deraadt Exp $ */
+/*	$OpenBSD: syscall.h,v 1.10 2002/12/18 19:20:01 drahn Exp $ */
 
 /*
  * Copyright (c) 2001 Niklas Hallqvist
@@ -36,6 +36,7 @@
 
 #include <sys/stat.h>
 #include <sys/syscall.h>
+#include <sys/signal.h>
 
 #ifndef _dl_MAX_ERRNO
 #define _dl_MAX_ERRNO 4096
@@ -57,6 +58,7 @@ int	_dl_fstat(int, struct stat *);
 int	_dl_fcntl(int, int, ...);
 int	_dl_getdirentries(int, char*, int, long *);
 long	_dl__syscall(quad_t, ...);
+int	_dl_sigprocmask(int, const sigset_t *, sigset_t *);
 
 static inline off_t
 _dl_lseek(int fildes, off_t offset, int whence)
diff --git a/libexec/ld.so/i386/ldasm.S b/libexec/ld.so/i386/ldasm.S
index b7af2be3792..c3ff47b5234 100644
--- a/libexec/ld.so/i386/ldasm.S
+++ b/libexec/ld.so/i386/ldasm.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ldasm.S,v 1.2 2002/10/21 16:01:55 drahn Exp $ */
+/*	$OpenBSD: ldasm.S,v 1.3 2002/12/18 19:20:02 drahn Exp $ */
 
 /*
  * Copyright (c) 2002 Dale Rahn
@@ -227,6 +227,31 @@ _dl_getdirentries:
 	ret
 
 
+	/* _dl_sigprocmask: does not handle NULL new set */
+
+	.section	".text"
+	.align		4
+	.global _dl_sigprocmask
+	.type _dl_sigprocmask,@function
+_dl_sigprocmask:
+	movl	8(%esp), %ecx
+	movl    (%ecx),%ecx
+	movl	%ecx,8(%esp)		# to new mask arg
+	mov	$SYS_sigprocmask, %eax
+	int	$0x80
+	jb	1f		 /* error: result = -errno */
+	movl	12(%esp),%ecx		# fetch old mask requested
+	testl	%ecx,%ecx		# test if old mask requested
+	jz	2f
+	movl	%eax,(%ecx)		# store old mask
+	xorl	%eax,%eax
+2:	ret
+
+1:	/* error: result = -errno; - handled here. */
+	neg	%eax
+	ret
+
+
 	.align 4
 	.global _dl_bind_start
 	.type _dl_bind_start,@function
diff --git a/libexec/ld.so/i386/rtld_machine.c b/libexec/ld.so/i386/rtld_machine.c
index 5495e42749b..e8ce94c1927 100644
--- a/libexec/ld.so/i386/rtld_machine.c
+++ b/libexec/ld.so/i386/rtld_machine.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: rtld_machine.c,v 1.5 2002/11/23 06:04:13 drahn Exp $ */
+/*	$OpenBSD: rtld_machine.c,v 1.6 2002/12/18 19:20:02 drahn Exp $ */
 
 /*
  * Copyright (c) 2002 Dale Rahn
@@ -77,6 +77,7 @@
 
 #include <nlist.h>
 #include <link.h>
+#include <signal.h>
 
 #include "syscall.h"
 #include "archdep.h"
@@ -332,6 +333,7 @@ resolve_failed:
 	return (fails);
 }
 
+#if 0
 struct jmpslot {
 	u_short opcode;
 	u_short addr[2];
@@ -339,6 +341,7 @@ struct jmpslot {
 #define JMPSLOT_RELOC_MASK              0xffff
 };
 #define JUMP    0xe990          /* NOP + JMP opcode */
+#endif
 
 void
 _dl_reloc_plt(Elf_Addr *where, Elf_Addr value)
@@ -357,6 +360,7 @@ _dl_bind(elf_object_t *object, int index)
 	const Elf_Sym *sym, *this;
 	const char *symn;
 	Elf_Addr ooff;
+	sigset_t omask, nmask;
 
 	rel = (Elf_Rel *)(object->Dyn.info[DT_JMPREL]);
 
@@ -375,8 +379,23 @@ _dl_bind(elf_object_t *object, int index)
 		*((int *)0) = 0;        /* XXX */
 	}
 
+	/* if GOT is protected, allow the write */
+	if (object->got_addr != NULL && object->got_size != 0) {
+		sigfillset(&nmask);
+		_dl_sigprocmask(SIG_BLOCK, &nmask, &omask);
+		_dl_mprotect((void*)object->got_addr, object->got_size,
+		    PROT_READ|PROT_WRITE); 
+	}
+
 	_dl_reloc_plt(addr, ooff + this->st_value);
 
+	/* put the GOT back to RO */
+	if (object->got_addr != NULL && object->got_size != 0) {
+		_dl_mprotect((void*)object->got_addr, object->got_size,
+		    PROT_READ);
+		_dl_sigprocmask(SIG_SETMASK, &omask, NULL);
+	}
+
 	return((Elf_Addr)ooff + this->st_value);
 }
 
@@ -388,6 +407,8 @@ _dl_md_reloc_got(elf_object_t *object, int lazy)
 	int i, num;
 	Elf_Rel *rel;
 	struct load_list *llist;
+	Elf_Addr ooff;
+	const Elf_Sym *this;
 
 	if (pltgot == NULL)
 		return; /* it is possible to have no PLT/GOT relocations */
@@ -398,6 +419,34 @@ _dl_md_reloc_got(elf_object_t *object, int lazy)
 	if (object->Dyn.info[DT_PLTREL] != DT_REL)
 		return;
 
+	this = NULL;
+	ooff = _dl_find_symbol("__got_start", object, &this,
+	    SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT,
+	    NULL);
+	if (this != NULL)
+		object->got_addr = ooff + this->st_value;
+
+	this = NULL;
+	ooff = _dl_find_symbol("__got_end", object, &this,
+	    SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT,
+	    NULL);
+	if (this != NULL)
+		object->got_size = ooff + this->st_value  - object->got_addr;
+
+	this = NULL;
+	ooff = _dl_find_symbol("__plt_start", object, &this,
+	    SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT,
+	    NULL);
+	if (this != NULL)
+		object->plt_addr = ooff + this->st_value;
+
+	this = NULL;
+	ooff = _dl_find_symbol("__plt_end", object, &this,
+	    SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT,
+	    NULL);
+	if (this != NULL)
+		object->plt_size = ooff + this->st_value  - object->plt_addr;
+
 	if (!lazy) {
 		_dl_md_reloc(object, DT_JMPREL, DT_PLTRELSZ);
 		return;
@@ -420,4 +469,9 @@ _dl_md_reloc_got(elf_object_t *object, int lazy)
 			_dl_mprotect(llist->start, llist->size,
 			    llist->prot);
 	}
+
+	/* PLT is already RO on i386, no point in mprotecting it, just GOT */
+	if (object->got_addr != NULL && object->got_size != 0) 
+		_dl_mprotect((void*)object->got_addr, object->got_size,
+		    PROT_READ); 
 }
diff --git a/libexec/ld.so/i386/syscall.h b/libexec/ld.so/i386/syscall.h
index c9719118dd1..f853ad4cb6c 100644
--- a/libexec/ld.so/i386/syscall.h
+++ b/libexec/ld.so/i386/syscall.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: syscall.h,v 1.1 2002/08/23 23:02:48 drahn Exp $ */
+/*	$OpenBSD: syscall.h,v 1.2 2002/12/18 19:20:02 drahn Exp $ */
 
 /*
  * Copyright (c) 2001 Niklas Hallqvist
@@ -37,6 +37,7 @@
 
 #include <sys/syscall.h>
 #include <sys/stat.h>
+#include <sys/signal.h>
 
 #ifndef _dl_MAX_ERRNO
 #define _dl_MAX_ERRNO 4096
@@ -57,6 +58,7 @@ int	_dl_write(int, const char*, int);
 int	_dl_fstat(int, struct stat *);
 int	_dl_fcntl(int, int, ...);
 int	_dl_getdirentries(int, char*, int, long *);
+int	_dl_sigprocmask(int, const sigset_t *, sigset_t *);
 
 static inline off_t
 _dl_lseek(int fildes, off_t offset, int whence)
diff --git a/libexec/ld.so/mips/rtld_machine.c b/libexec/ld.so/mips/rtld_machine.c
index b58e689e7fa..45467e3b9cf 100644
--- a/libexec/ld.so/mips/rtld_machine.c
+++ b/libexec/ld.so/mips/rtld_machine.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: rtld_machine.c,v 1.9 2002/11/14 15:15:54 drahn Exp $ */
+/*	$OpenBSD: rtld_machine.c,v 1.10 2002/12/18 19:20:02 drahn Exp $ */
 
 /*
  * Copyright (c) 1998-2002 Opsycon AB, Sweden.
@@ -129,6 +129,8 @@ _dl_md_reloc_got(elf_object_t *object, int lazy)
 	const Elf32_Sym  *symp;
 	const Elf32_Sym  *this;
 	const char *strt;
+	Elf_Addr ooff;
+	const Elf_Sym *this;
 
 	if (object->status & STAT_GOT_DONE)
 		return;
@@ -159,6 +161,34 @@ _dl_md_reloc_got(elf_object_t *object, int lazy)
 	n =  object->Dyn.info[DT_MIPS_SYMTABNO - DT_LOPROC + DT_NUM] -
 	    object->Dyn.info[DT_MIPS_GOTSYM - DT_LOPROC + DT_NUM];
 
+	this = NULL;
+	ooff = _dl_find_symbol("__got_start", object, &this,
+	    SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT,
+	    NULL);
+	if (this != NULL)
+		object->got_addr = ooff + this->st_value;
+
+	this = NULL;
+	ooff = _dl_find_symbol("__got_end", object, &this,
+	    SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT,
+	    NULL);
+	if (this != NULL)
+		object->got_size = ooff + this->st_value  - object->got_addr;
+
+	this = NULL;
+	ooff = _dl_find_symbol("__plt_start", object, &this,
+	    SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT,
+	    NULL);
+	if (this != NULL)
+		object->plt_addr = ooff + this->st_value;
+
+	this = NULL;
+	ooff = _dl_find_symbol("__plt_end", object, &this,
+	    SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT,
+	    NULL);
+	if (this != NULL)
+		object->plt_size = ooff + this->st_value  - object->plt_addr;
+
 	/*
 	 *  Then do all global references according to the ABI.
 	 *  Quickstart is not yet implemented.
@@ -195,4 +225,11 @@ DL_DEB(("got: '%s' = %x\n", strt + symp->st_name, symp->st_value));
 		symp++;
 	}
 	object->status |= STAT_GOT_DONE;
+
+	if (object->got_addr != NULL && object->got_size != 0) 
+		_dl_mprotect((void*)object->got_addr, object->got_size,
+		    PROT_READ); 
+	if (object->plt_addr != NULL && object->plt_size != 0) 
+		_dl_mprotect((void*)object->plt_addr, object->plt_size,
+		    PROT_READ|PROT_EXEC);
 }
diff --git a/libexec/ld.so/powerpc/rtld_machine.c b/libexec/ld.so/powerpc/rtld_machine.c
index ac6cb26fa93..5e44c314f04 100644
--- a/libexec/ld.so/powerpc/rtld_machine.c
+++ b/libexec/ld.so/powerpc/rtld_machine.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: rtld_machine.c,v 1.18 2002/11/22 22:21:23 drahn Exp $ */
+/*	$OpenBSD: rtld_machine.c,v 1.19 2002/12/18 19:20:02 drahn Exp $ */
 
 /*
  * Copyright (c) 1999 Dale Rahn
@@ -39,6 +39,7 @@
 
 #include <nlist.h>
 #include <link.h>
+#include <signal.h>
 
 #include "syscall.h"
 #include "archdep.h"
@@ -450,10 +451,40 @@ _dl_md_reloc_got(elf_object_t *object, int lazy)
 	int i;
 	int index;
 	Elf32_Addr *r_addr;
+	Elf_Addr ooff;
+	const Elf_Sym *this;
 
 	if (object->Dyn.info[DT_PLTREL] != DT_RELA)
 		return;
 
+	this = NULL;
+	ooff = _dl_find_symbol("__got_start", object, &this,
+	    SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT,
+	    NULL);
+	if (this != NULL)
+		object->got_addr = ooff + this->st_value;
+
+	this = NULL;
+	ooff = _dl_find_symbol("__got_end", object, &this,
+	    SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT,
+	    NULL);
+	if (this != NULL)
+		object->got_size = ooff + this->st_value  - object->got_addr;
+
+	this = NULL;
+	ooff = _dl_find_symbol("__plt_start", object, &this,
+	    SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT,
+	    NULL);
+	if (this != NULL)
+		object->plt_addr = ooff + this->st_value;
+
+	this = NULL;
+	ooff = _dl_find_symbol("__plt_end", object, &this,
+	    SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT,
+	    NULL);
+	if (this != NULL)
+		object->plt_size = ooff + this->st_value  - object->plt_addr;
+
 	if (!lazy) {
 		_dl_md_reloc(object, DT_JMPREL, DT_PLTRELSZ);
 		return;
@@ -483,6 +514,12 @@ _dl_md_reloc_got(elf_object_t *object, int lazy)
 		_dl_dcbf(&r_addr[0]);
 		_dl_dcbf(&r_addr[2]);
 	}
+	if (object->got_addr != NULL && object->got_size != 0) 
+		_dl_mprotect((void*)object->got_addr, object->got_size,
+		    PROT_READ|PROT_EXEC); /* only PPC is PROT_EXE */
+	if (object->plt_addr != NULL && object->plt_size != 0) 
+		_dl_mprotect((void*)object->plt_addr, object->plt_size,
+		    PROT_READ|PROT_EXEC);
 }
 
 Elf_Addr
@@ -498,6 +535,7 @@ _dl_bind(elf_object_t *object, int reloff)
 	Elf32_Addr *pltcall;
 	Elf32_Addr *pltinfo;
 	Elf32_Addr *plttable;
+	sigset_t omask, nmask;
 
 	relas = ((Elf_RelA *)object->Dyn.info[DT_JMPREL]) + (reloff>>2);
 
@@ -515,6 +553,14 @@ _dl_bind(elf_object_t *object, int reloff)
 		*((int *)0) = 0;	/* XXX */
 	}
 
+	/* if PLT is protected, allow the write */
+	if (object->plt_addr != NULL && object->plt_size != 0)  {
+		sigfillset(&nmask);
+		_dl_sigprocmask(SIG_BLOCK, &nmask, &omask);
+		_dl_mprotect((void*)object->plt_addr, object->plt_size,
+		    PROT_READ|PROT_WRITE|PROT_EXEC); 
+	}
+
 	value = ooff + this->st_value;
 
 	val = value - (Elf32_Addr)r_addr;
@@ -558,6 +604,12 @@ _dl_bind(elf_object_t *object, int reloff)
 		_dl_dcbf(&r_addr[0]);
 	}
 
+	/* if PLT is (to be protected, change back to RO/X */
+	if (object->plt_addr != NULL && object->plt_size != 0) {
+		_dl_mprotect((void*)object->plt_addr, object->plt_size,
+		    PROT_READ|PROT_EXEC); /* only PPC is PROT_EXE */
+		_dl_sigprocmask(SIG_SETMASK, &omask, NULL);
+	}
 	return (value);
 }
 
diff --git a/libexec/ld.so/powerpc/syscall.h b/libexec/ld.so/powerpc/syscall.h
index 55bcb55b36f..92de932f7f5 100644
--- a/libexec/ld.so/powerpc/syscall.h
+++ b/libexec/ld.so/powerpc/syscall.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: syscall.h,v 1.13 2002/07/24 04:11:10 deraadt Exp $ */
+/*	$OpenBSD: syscall.h,v 1.14 2002/12/18 19:20:02 drahn Exp $ */
 
 /*
  * Copyright (c) 1998 Per Fogelstrom, Opsycon AB
@@ -37,6 +37,7 @@
 #include <sys/stat.h>
 
 #include <sys/syscall.h>
+#include <sys/signal.h>
 
 
 static off_t	_dl_lseek(int, off_t, int);
@@ -306,4 +307,29 @@ _dl_lseek(int fildes, off_t offset, int whence)
 {
 	return _dl__syscall((quad_t)SYS_lseek, fildes, 0, offset, whence);
 }
+
+static inline int
+_dl_sigprocmask (int how, const sigset_t *set, sigset_t *oset)
+{
+	sigset_t sig_store;
+	sigset_t sig_store1;
+	if (set != NULL) {
+		sig_store1 = *set;
+	} else {
+		sig_store1 = 0;
+	}
+
+	__asm__ volatile ("li    0,%1\n\t"
+	    "mr    3,%2\n\t"
+	    "mr    4,%3\n\t"
+	    "sc\n\t"
+	    "mr    %0, 3"
+	    : "=r" (sig_store)
+	    : "I" (SYS_sigprocmask), "r" (how), "r" (sig_store1)
+	    : "0", "3", "4");
+	if (oset != NULL)
+		*oset = sig_store;
+
+	return 0;
+}
 #endif /*__DL_SYSCALL_H__*/
diff --git a/libexec/ld.so/resolve.h b/libexec/ld.so/resolve.h
index 8e0060698d3..52a99e303c9 100644
--- a/libexec/ld.so/resolve.h
+++ b/libexec/ld.so/resolve.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: resolve.h,v 1.18 2002/11/14 15:15:54 drahn Exp $ */
+/*	$OpenBSD: resolve.h,v 1.19 2002/12/18 19:20:01 drahn Exp $ */
 
 /*
  * Copyright (c) 1998 Per Fogelstrom, Opsycon AB
@@ -61,6 +61,10 @@ typedef struct elf_object {
 	struct load_list *load_list;
 
 	u_int32_t  load_size;
+	Elf_Addr	got_addr;
+	size_t		got_size;
+	Elf_Addr	plt_addr;
+	size_t		plt_size;
 
 	union {
 		u_long		info[DT_NUM + DT_PROCNUM];
diff --git a/libexec/ld.so/sparc/ldasm.S b/libexec/ld.so/sparc/ldasm.S
index 9b3ff9fb81f..c7a3cf5f86c 100644
--- a/libexec/ld.so/sparc/ldasm.S
+++ b/libexec/ld.so/sparc/ldasm.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ldasm.S,v 1.9 2002/11/23 19:50:45 drahn Exp $	*/
+/*	$OpenBSD: ldasm.S,v 1.10 2002/12/18 19:20:02 drahn Exp $	*/
 
 /*
  * Copyright (c) 2001 Jason L. Wright (jason@thought.net)
@@ -292,6 +292,24 @@ _dl_sysctl:
 	retl
 	 sub %g0, %o0, %o0                      ! error: result = -errno
 
+
+	/* _dl_sigprocmask does not support NULL new mask */
+	.section ".text"
+	.align 4
+	.globl _dl_sigprocmask
+	.type _dl_sigprocmask,@function
+_dl_sigprocmask:
+	ld	[%o1], %o1
+	mov	SYS_sigprocmask, %g1			! call sys___sigprocmask
+	t	ST_SYSCALL				! off to wonderland
+
+	cmp	%o2, 0
+	bne,a	1f
+	 st	%o0, [%o2]
+1:	
+	retl
+	 clr	%o0
+
 /*
  * V8 sparc .{,u}{mul,div,rem} replacements.
  * We try to mimic them 100%.  Full 64 bit sources or outputs, and
diff --git a/libexec/ld.so/sparc/rtld_machine.c b/libexec/ld.so/sparc/rtld_machine.c
index 73ccd4ffc3b..48c16f7fe98 100644
--- a/libexec/ld.so/sparc/rtld_machine.c
+++ b/libexec/ld.so/sparc/rtld_machine.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: rtld_machine.c,v 1.10 2002/11/23 19:14:25 drahn Exp $ */
+/*	$OpenBSD: rtld_machine.c,v 1.11 2002/12/18 19:20:02 drahn Exp $ */
 
 /*
  * Copyright (c) 1999 Dale Rahn
@@ -44,6 +44,7 @@
 
 #include <nlist.h>
 #include <link.h>
+#include <signal.h>
 
 #include "syscall.h"
 #include "archdep.h"
@@ -335,6 +336,7 @@ _dl_bind(elf_object_t *object, Elf_Word reloff)
 	const char *symn;
 	Elf_Addr value;
 	Elf_RelA *rela;
+	sigset_t omask, nmask;
 
 	rela = (Elf_RelA *)(object->Dyn.info[DT_JMPREL] + reloff);
 
@@ -353,8 +355,33 @@ _dl_bind(elf_object_t *object, Elf_Word reloff)
 
 	value = ooff + this->st_value;
 
+	/* if PLT is protected, allow the write */
+	if (object->plt_addr != NULL && object->plt_size != 0) {
+		sigfillset(&nmask);
+		_dl_sigprocmask(SIG_BLOCK, &nmask, &omask);
+#if 0
+		_dl_mprotect((void*)object->plt_addr, object->plt_size,
+		    PROT_READ|PROT_WRITE|PROT_EXEC); 
+#else
+		_dl_mprotect((void*)addr,sizeof (Elf_Addr) * 3,
+		    PROT_READ|PROT_WRITE|PROT_EXEC); 
+#endif
+	}
+
 	_dl_reloc_plt(addr, value);
 
+	/* if PLT is (to be protected, change back to RO/X */
+	if (object->plt_addr != NULL && object->plt_size != 0) {
+#if 0
+		_dl_mprotect((void*)object->plt_addr, object->plt_size,
+		    PROT_READ|PROT_EXEC);
+#else
+		_dl_mprotect((void*)addr,sizeof (Elf_Addr) * 3,
+		    PROT_READ|PROT_EXEC); 
+#endif
+		_dl_sigprocmask(SIG_SETMASK, &omask, NULL);
+	}
+
 	return (value);
 }
 
@@ -363,6 +390,8 @@ _dl_md_reloc_got(elf_object_t *object, int lazy)
 {
 	Elf_Addr *pltgot;
 	extern void _dl_bind_start(void);	/* XXX */
+	Elf_Addr ooff;
+	const Elf_Sym *this;
 
 	pltgot = (Elf_Addr *)object->Dyn.info[DT_PLTGOT];
 
@@ -393,11 +422,45 @@ _dl_md_reloc_got(elf_object_t *object, int lazy)
 		__asm __volatile("nop;nop;nop;nop;nop");
 	}
 
+	this = NULL;
+	ooff = _dl_find_symbol("__got_start", object, &this,
+	    SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT,
+	    NULL);
+	if (this != NULL)
+		object->got_addr = ooff + this->st_value;
+
+	this = NULL;
+	ooff = _dl_find_symbol("__got_end", object, &this,
+	    SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT,
+	    NULL);
+	if (this != NULL)
+		object->got_size = ooff + this->st_value  - object->got_addr;
+
+	this = NULL;
+	ooff = _dl_find_symbol("__plt_start", object, &this,
+	    SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT,
+	    NULL);
+	if (this != NULL)
+		object->plt_addr = ooff + this->st_value;
+
+	this = NULL;
+	ooff = _dl_find_symbol("__plt_end", object, &this,
+	    SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT,
+	    NULL);
+	if (this != NULL)
+		object->plt_size = ooff + this->st_value  - object->plt_addr;
+
 	if (object->obj_type == OBJTYPE_LDR || !lazy || pltgot == NULL) {
 		_dl_md_reloc(object, DT_JMPREL, DT_PLTRELSZ);
 		return;
 	}
 
+	if (object->got_addr != NULL && object->got_size != 0) 
+		_dl_mprotect((void*)object->got_addr, object->got_size,
+		    PROT_READ); 
+	if (object->plt_addr != NULL && object->plt_size != 0) 
+		_dl_mprotect((void*)object->plt_addr, object->plt_size,
+		    PROT_READ|PROT_EXEC);
 }
 
 
diff --git a/libexec/ld.so/sparc/syscall.h b/libexec/ld.so/sparc/syscall.h
index c11613b6120..ac19f7fb0ca 100644
--- a/libexec/ld.so/sparc/syscall.h
+++ b/libexec/ld.so/sparc/syscall.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: syscall.h,v 1.2 2002/11/23 19:14:25 drahn Exp $ */
+/*	$OpenBSD: syscall.h,v 1.3 2002/12/18 19:20:02 drahn Exp $ */
 
 /*
  * Copyright (c) 2001 Niklas Hallqvist
@@ -37,6 +37,7 @@
 
 #include <sys/syscall.h>
 #include <sys/stat.h>
+#include <sys/signal.h>
 
 #ifndef _dl_MAX_ERRNO
 #define _dl_MAX_ERRNO 4096
@@ -59,6 +60,7 @@ int	_dl_fcntl(int, int, ...);
 int	_dl_getdirentries(int, char*, int, long *);
 
 int	_dl_sysctl(int *, u_int, void *, size_t *, void *, size_t);
+int	_dl_sigprocmask(int, const sigset_t *, sigset_t *);
 
 static inline off_t
 _dl_lseek(int fildes, off_t offset, int whence)
diff --git a/libexec/ld.so/sparc64/ldasm.S b/libexec/ld.so/sparc64/ldasm.S
index 574f065c1ea..2391fbe1b40 100644
--- a/libexec/ld.so/sparc64/ldasm.S
+++ b/libexec/ld.so/sparc64/ldasm.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ldasm.S,v 1.15 2002/11/23 06:19:26 drahn Exp $	*/
+/*	$OpenBSD: ldasm.S,v 1.16 2002/12/18 19:20:02 drahn Exp $	*/
 /*	$NetBSD: rtld_start.S,v 1.5 2001/08/14 22:17:48 eeh Exp $	*/
 
 /*
@@ -366,3 +366,21 @@ _dl_getdirentries:
 	t ST_SYSCALL					! off to wonderland
 	retl
 	 sub %g0, %o0, %o0                      ! error: result = -errno
+
+
+	/* _dl_sigprocmask does not support NULL new mask */
+	.section ".text"
+	.align 4
+	.globl _dl_sigprocmask
+	.type _dl_sigprocmask,@function
+_dl_sigprocmask:
+	ld	[%o1], %o1			! indirect for new mask
+	mov	SYS_sigprocmask, %g1		! call sys_sigprocmask
+	t ST_SYSCALL				! off to wonderland
+						! what about errors? 
+	cmp	%o2, 0
+	bne,a	1f				! if oset != NULL
+	 st	%o0, [%o2]			!   *oset = oldmask
+1:
+	retl
+	 clr %o0
diff --git a/libexec/ld.so/sparc64/rtld_machine.c b/libexec/ld.so/sparc64/rtld_machine.c
index d44c20888a2..a46e471b300 100644
--- a/libexec/ld.so/sparc64/rtld_machine.c
+++ b/libexec/ld.so/sparc64/rtld_machine.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: rtld_machine.c,v 1.22 2002/11/14 15:15:54 drahn Exp $ */
+/*	$OpenBSD: rtld_machine.c,v 1.23 2002/12/18 19:20:02 drahn Exp $ */
 
 /*
  * Copyright (c) 1999 Dale Rahn
@@ -77,6 +77,7 @@
 
 #include <nlist.h>
 #include <link.h>
+#include <signal.h>
 
 #include "syscall.h"
 #include "archdep.h"
@@ -602,6 +603,7 @@ _dl_bind(elf_object_t *object, int index)
 	Elf_Addr ooff;
 	const Elf_Sym *sym, *this;
 	const char *symn;
+	sigset_t omask, nmask;
 
 	rela = (Elf_RelA *)(object->Dyn.info[DT_JMPREL]);
 	if (ELF_R_TYPE(rela->r_info) == R_TYPE(JMP_SLOT)) {
@@ -641,8 +643,23 @@ _dl_bind(elf_object_t *object, int index)
 		*((int *)0) = 0;	/* XXX */
 	}
 
+	/* if PLT is protected, allow the write */
+	if (object->plt_addr != NULL && object->plt_size != 0)  {
+		sigfillset(&nmask);
+		_dl_sigprocmask(SIG_BLOCK, &nmask, &omask);
+		_dl_mprotect((void*)object->plt_addr, object->plt_size,
+		    PROT_READ|PROT_WRITE|PROT_EXEC); 
+	}
+
 	_dl_reloc_plt(addr, ooff + this->st_value, rela);
 
+	/* if PLT is (to be protected), change back to RO/X */
+	if (object->plt_addr != NULL && object->plt_size != 0) {
+		_dl_mprotect((void*)object->plt_addr, object->plt_size,
+		    PROT_READ|PROT_EXEC); 
+		_dl_sigprocmask(SIG_SETMASK, &omask, NULL);
+	}
+
 	return (void *)ooff + this->st_value;
 }
 
@@ -682,10 +699,40 @@ _dl_md_reloc_got(elf_object_t *object, int lazy)
 {
 	Elf_Addr *pltgot = (Elf_Addr *)object->Dyn.info[DT_PLTGOT];
 	Elf_Word *entry = (Elf_Word *)pltgot;
+	Elf_Addr ooff;
+	const Elf_Sym *this;
 
 	if (object->Dyn.info[DT_PLTREL] != DT_RELA)
 		return;
 
+	this = NULL;
+	ooff = _dl_find_symbol("__got_start", object, &this,
+	    SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT,
+	    NULL);
+	if (this != NULL)
+		object->got_addr = ooff + this->st_value;
+
+	this = NULL;
+	ooff = _dl_find_symbol("__got_end", object, &this,
+	    SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT,
+	    NULL);
+	if (this != NULL)
+		object->got_size = ooff + this->st_value  - object->got_addr;
+
+	this = NULL;
+	ooff = _dl_find_symbol("__plt_start", object, &this,
+	    SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT,
+	    NULL);
+	if (this != NULL)
+		object->plt_addr = ooff + this->st_value;
+	 
+	this = NULL;
+	ooff = _dl_find_symbol("__plt_end", object, &this,
+	    SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT,
+	    NULL);
+	if (this != NULL)
+		object->plt_size = ooff + this->st_value  - object->plt_addr;
+
 	if (!lazy) {
 		_dl_md_reloc(object, DT_JMPREL, DT_PLTRELSZ);
 		return;
@@ -695,4 +742,11 @@ _dl_md_reloc_got(elf_object_t *object, int lazy)
 	_dl_install_plt(&entry[8], (Elf_Addr)&_dl_bind_start_1);
 
 	pltgot[8] = (Elf_Addr)object;
+
+	if (object->got_addr != NULL && object->got_size != 0) 
+		_dl_mprotect((void*)object->got_addr, object->got_size,
+		    PROT_READ); 
+	if (object->plt_addr != NULL && object->plt_size != 0) 
+		_dl_mprotect((void*)object->plt_addr, object->plt_size,
+		    PROT_READ|PROT_EXEC);
 }
diff --git a/libexec/ld.so/sparc64/syscall.h b/libexec/ld.so/sparc64/syscall.h
index 2370348b169..cd39a0550c7 100644
--- a/libexec/ld.so/sparc64/syscall.h
+++ b/libexec/ld.so/sparc64/syscall.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: syscall.h,v 1.10 2002/07/24 04:11:10 deraadt Exp $ */
+/*	$OpenBSD: syscall.h,v 1.11 2002/12/18 19:20:02 drahn Exp $ */
 
 /*
  * Copyright (c) 2001 Niklas Hallqvist
@@ -37,6 +37,7 @@
 
 #include <sys/syscall.h>
 #include <sys/stat.h>
+#include <sys/signal.h>
 
 #ifndef _dl_MAX_ERRNO
 #define _dl_MAX_ERRNO 4096
@@ -57,6 +58,7 @@ ssize_t	_dl_write(int, const char*, size_t);
 int	_dl_fstat(int, struct stat *);
 int	_dl_fcntl(int, int, ...);
 int	_dl_getdirentries(int, char*, int, long *);
+int	_dl_sigprocmask(int, const sigset_t *, sigset_t *);
 
 static inline off_t
 _dl_lseek(int fildes, off_t offset, int whence)