copy the alpha/elfrdsetroot to common (for more general use: macppc, sparc64, etc)

1 files changed, 223 insertions, 0 deletions

diff --git a/distrib/common/elfrdsetroot.c b/distrib/common/elfrdsetroot.c
new file mode 100644
index 00000000000..dfa786720f5
--- /dev/null
+++ b/distrib/common/elfrdsetroot.c
@@ -0,0 +1,223 @@
+/*	$OpenBSD: elfrdsetroot.c,v 1.1 2001/09/18 15:24:18 jason Exp $	*/
+/*	$NetBSD: rdsetroot.c,v 1.2 1995/10/13 16:38:39 gwr Exp $	*/
+
+/*
+ * Copyright (c) 1994 Gordon W. Ross
+ * All rights reserved.
+ *
+ * ELF modifications Copyright (c) 1997 Per Fogelstrom.
+ *
+ * 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.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * 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.
+ */
+
+/*
+ * Copy a ramdisk image into the space reserved for it.
+ * Kernel variables: rd_root_size, rd_root_image
+ */
+
+#include <sys/types.h>
+#include <sys/file.h>
+#include <sys/mman.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <nlist.h>
+
+#ifdef __alpha__	/* XXXXXXX */
+#define ELFSIZE 64
+#else
+#define ELFSIZE 32
+#endif
+
+#include <sys/exec_elf.h>
+
+extern off_t lseek();
+
+char *file;
+
+/* Virtual addresses of the symbols we frob. */
+long rd_root_image_va, rd_root_size_va;
+
+/* Offsets relative to start of data segment. */
+long rd_root_image_off, rd_root_size_off;
+
+/* value in the location at rd_root_size_off */
+off_t rd_root_size_val;
+
+/* pointers to pieces of mapped file */
+char *dataseg;
+
+/* parameters to mmap digged out from program header */
+off_t mmap_offs;
+size_t mmap_size;
+
+int find_rd_root_image(char *, Elf_Ehdr *, Elf_Phdr *);
+
+int
+main(argc,argv)
+	char **argv;
+{
+	int fd, n;
+	int found;
+	int *ip;
+	Elf_Ehdr eh;
+	Elf_Phdr *ph;
+	int phsize;
+
+	if (argc < 2) {
+		printf("%s: missing file name\n", argv[0]);
+		exit(1);
+	}
+	file = argv[1];
+
+	fd = open(file, O_RDWR);
+	if (fd < 0) {
+		perror(file);
+		exit(1);
+	}
+
+	n = read(fd, &eh, sizeof(eh));
+	if (n < sizeof(eh)) {
+		printf("%s: reading header\n", file);
+		exit(1);
+	}
+
+	if (!IS_ELF(eh)) {
+		printf("%s: not elf\n", file);
+		exit(1);
+	}
+
+	phsize = eh.e_phnum * sizeof(Elf_Phdr);
+	ph = (Elf_Phdr *)malloc(phsize);
+	lseek(fd,  eh.e_phoff, 0);
+	if (read(fd, (char *)ph, phsize) != phsize) {
+		printf("%s: can't read phdr area\n", file);
+		exit(1);
+	}
+	found = 0;
+	for(n = 0; n < eh.e_phnum && !found; n++) {
+		if(ph[n].p_type == PT_LOAD) {
+			found = find_rd_root_image(file, &eh, &ph[n]);
+		}
+	}
+	if (!found) {
+		printf("%s: can't locate space for rd_root_image!", file);
+		exit(1);
+	}
+
+	/*
+	 * Map in the whole data segment.
+	 * The file offset needs to be page aligned.
+	 */
+	dataseg = mmap(NULL,	/* any address is ok */
+				   mmap_size, /* length */
+				   PROT_READ | PROT_WRITE,
+				   MAP_SHARED,
+				   fd, mmap_offs);
+	if (dataseg == MAP_FAILED) {
+		printf("%s: can not map data seg\n", file);
+		perror(file);
+		exit(1);
+	}
+
+	/*
+	 * Find value in the location: rd_root_size
+	 */
+	ip = (int*) (dataseg + rd_root_size_off);
+	rd_root_size_val = *ip;
+#ifdef	DEBUG
+	printf("rd_root_size  val: 0x%08X (%d blocks)\n",
+		rd_root_size_val, (rd_root_size_val >> 9));
+#endif
+
+	/*
+	 * Copy the symbol table and string table.
+	 */
+#ifdef	DEBUG
+	printf("copying root image...\n");
+#endif
+	n = read(0, dataseg + rd_root_image_off,
+			 rd_root_size_val);
+	if (n < 0) {
+		perror("read");
+		exit(1);
+	}
+
+	msync(dataseg, mmap_size, 0);
+
+#ifdef	DEBUG
+	printf("...copied %d bytes\n", n);
+#endif
+	close(fd);
+	exit(0);
+}
+
+
+/*
+ * Find locations of the symbols to patch.
+ */
+struct nlist wantsyms[] = {
+	{ "_rd_root_size", 0 },
+	{ "_rd_root_image", 0 },
+	{ NULL, 0 },
+};
+
+int
+find_rd_root_image(file, eh, ph)
+	char *file;
+	Elf_Ehdr *eh;
+	Elf_Phdr *ph;
+{
+	unsigned long kernel_start;
+	unsigned long kernel_size;
+
+	if (nlist(file, wantsyms)) {
+		printf("%s: no rd_root_image symbols?\n", file);
+		exit(1);
+	}
+	kernel_start = ph->p_paddr;
+	kernel_size = ph->p_filesz;
+
+	rd_root_size_off = wantsyms[0].n_value - kernel_start;
+	rd_root_image_off     = wantsyms[1].n_value - kernel_start;
+
+#ifdef DEBUG
+	printf("rd_root_size_off = 0x%x\n", rd_root_size_off);
+	printf("rd_root_image_off = 0x%x\n", rd_root_image_off);
+#endif
+
+	/*
+	 * Sanity check locations of db_* symbols
+	 */
+	if (rd_root_image_off < 0 || rd_root_image_off >= kernel_size) {
+		return(0);
+	}
+	if (rd_root_size_off < 0 || rd_root_size_off >= kernel_size) {
+		printf("%s: rd_root_size not in data segment?\n", file);
+		return(0);
+	}
+	mmap_offs = ph->p_offset;
+	mmap_size =  kernel_size;
+	return(1);
+}