Use the new Elfxx_Phdr check hook to prevent loading a kernel not compiled

for the platform we are running on (i.e. trying to boot e.g. bsd.IP32 on an
IP27 machine).

2 files changed, 43 insertions, 3 deletions

diff --git a/sys/arch/sgi/include/loadfile_machdep.h b/sys/arch/sgi/include/loadfile_machdep.h
index 85b30239159..5bdbd672515 100644
--- a/sys/arch/sgi/include/loadfile_machdep.h
+++ b/sys/arch/sgi/include/loadfile_machdep.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: loadfile_machdep.h,v 1.3 2008/06/26 05:42:12 ray Exp $ */
+/*	$OpenBSD: loadfile_machdep.h,v 1.4 2009/11/30 05:19:18 miod Exp $ */
 /*	$NetBSD: loadfile_machdep.h,v 1.2 2001/10/31 17:20:49 thorpej Exp $	 */
 
 /*-
@@ -47,4 +47,6 @@
 #define PROGRESS(a)		(void) printf a
 #define ALLOC(a)		alloc(a)
 #define FREE(a, b)		free(a, b)
-#define OKMAGIC(a)		((a) == OMAGIC)
+
+extern int check_phdr(void *);
+#define	CHECK_PHDR(sz,phdr)	check_phdr(phdr)
diff --git a/sys/arch/sgi/stand/boot/boot.c b/sys/arch/sgi/stand/boot/boot.c
index 27c597ec9ff..c5451b603bf 100644
--- a/sys/arch/sgi/stand/boot/boot.c
+++ b/sys/arch/sgi/stand/boot/boot.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: boot.c,v 1.14 2009/11/24 13:31:41 miod Exp $ */
+/*	$OpenBSD: boot.c,v 1.15 2009/11/30 05:19:20 miod Exp $ */
 
 /*
  * Copyright (c) 2004 Opsycon AB, www.opsycon.se.
@@ -34,6 +34,7 @@
 #include <mips64/arcbios.h>
 #include <mips64/cpu.h>
 
+#include <sys/exec_elf.h>
 #include "loadfile.h"
 
 char *strstr(char *, const char *);	/* strstr.c */
@@ -175,3 +176,40 @@ dobootopts(int argc, char **argv)
 		}
 	}
 }
+
+/*
+ * Prevent loading a wrong kernel.
+ */
+int
+check_phdr(void *v)
+{
+	Elf64_Phdr *phdr = (Elf64_Phdr *)v;
+	uint64_t addr;
+
+	switch (IP) {
+	case 27:
+		addr = 0xa800000000000000ULL >> 28;
+		break;
+	case 30:
+		addr = 0xa800000020000000ULL >> 28;
+		break;
+	case 32:
+		addr = 0xffffffff80000000ULL >> 28;
+		break;
+	default:
+		/*
+		 * If the system could not be identified, accept any
+		 * address and hope the user knows what's he's doing.
+		 */
+		return 0;
+	}
+
+	if ((phdr->p_vaddr >> 28) != addr) {
+		/* I'm sorry Dave, I can't let you do that. */
+		printf("This kernel does not seem to be compiled for this"
+		    " machine type.\nYou need to boot an IP%d kernel.\n", IP);
+		return 1;
+	}
+
+	return 0;
+}