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/* $OpenBSD: ecoffrdsetroot.c,v 1.4 2002/02/16 21:27:08 millert Exp $ */
/*
* Copyright (c) 1997 Todd C. Milller
* Copyright (c) 1994 Gordon W. Ross
* 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.
* 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 <err.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/param.h>
#include <sys/file.h>
#include <sys/mman.h>
#include <sys/exec_ecoff.h>
#include <nlist.h>
void find_rd_root_image(char *);
struct ecoff_exechdr head;
char *file;
/* Virtual addresses of the symbols we frob. */
u_long rd_root_image_va, rd_root_size_va;
/* Offsets relative to start of data segment. */
off_t rd_root_image_off, rd_root_size_off;
/* value in the location at rd_root_size_off */
u_int32_t rd_root_size_val;
/* pointers to pieces of mapped file */
caddr_t dataseg;
/* and lengths */
size_t data_len;
off_t data_off;
u_int data_pgoff;
/*
* To find locations of the symbols to patch.
*/
struct nlist wantsyms[] = {
{ "_rd_root_size", 0 },
{ "_rd_root_image", 0 },
{ NULL, 0 },
};
int
main(argc,argv)
int argc;
char **argv;
{
int fd, n;
u_int32_t *ip;
if (argc < 2)
errx(1, "missing file name");
file = argv[1];
fd = open(file, O_RDWR);
if (fd < 0)
err(1, "open %s", file);
n = read(fd, &head, sizeof(head));
if (n < sizeof(head))
errx(1, "%s: short read reading header", file);
if (head.a.magic != ECOFF_OMAGIC)
errx(1, "%s: bad magic number (0%o)", file, head.a.magic);
#ifdef DEBUG
printf("ecoff header\n");
printf(" nscns: %9ld\n", head.f.f_nscns);
printf("timdat: %9ld\n", head.f.f_timdat);
printf("symptr: %9ld\n", head.f.f_symptr);
printf(" nsyms: %9ld\n", head.f.f_nsyms);
printf("opthdr: %9ld\n", head.f.f_opthdr);
printf(" flags: %9ld\n", head.f.f_flags);
printf("a.out header\n");
printf("vstamp: %9ld\n", head.a.vstamp);
printf(" tsize: %9ld\n", head.a.tsize);
printf(" dsize: %9ld\n", head.a.dsize);
printf(" bsize: %9ld\n", head.a.bsize);
printf(" entry: 0x%016lx\n", head.a.entry);
printf(" text: 0x%016lx\n", head.a.text_start);
printf(" data: 0x%016lx\n", head.a.data_start);
printf(" bss: 0x%016lx\n", head.a.bss_start);
#endif
if (head.f.f_nsyms <= 0)
errx(1, "%s: no symbols", file);
find_rd_root_image(file);
/*
* Map in the whole data segment.
* The file offset needs to be page aligned.
*/
data_off = ECOFF_DATOFF(&head);
data_len = head.a.dsize;
/* align... */
data_pgoff = NBPG - 1;
data_pgoff &= data_off;
#ifdef DEBUG
printf("data parameters\n");
printf(" data_off: 0x%016lx\n", data_off);
printf(" data_len: 0x%016lx\n", data_len);
printf(" data_pgoff: 0x%08x\n", data_pgoff);
#endif
data_off -= data_pgoff;
data_len += data_pgoff;
#ifdef DEBUG
printf("adjusted parameters\n");
printf(" data_off: 0x%016lx\n", data_off);
printf(" data_len: 0x%016lx\n", data_len);
#endif
/* Map it in... */
dataseg = mmap(NULL, data_len, PROT_READ | PROT_WRITE,
MAP_FILE | MAP_SHARED, fd, data_off);
if (dataseg == MAP_FAILED)
err(1, "%s: can not map data seg", file);
dataseg += data_pgoff;
/*
* Find value in the location: rd_root_size
*/
ip = (u_int32_t *)(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 root image
*/
#ifdef DEBUG
printf("copying root image...\n");
#endif
n = read(0, dataseg + rd_root_image_off, rd_root_size_val);
if (n < 0)
err(1, "read root image");
#ifdef DEBUG
printf("...copied %d bytes\n", n);
#endif
close(fd);
exit(0);
}
void
find_rd_root_image(file)
char *file;
{
u_long data_va = head.a.data_start;
if (nlist(file, wantsyms))
errx(1, "%s: no rd_root_image symbols?", file);
rd_root_size_off = wantsyms[0].n_value - data_va;
rd_root_image_off = wantsyms[1].n_value - data_va;
#ifdef DEBUG
printf(".data segment va: 0x%016lx\n", data_va);
printf("rd_root_size va: 0x%016lx\n", wantsyms[0].n_value);
printf("rd_root_image va: 0x%016lx\n", wantsyms[1].n_value);
printf("rd_root_size off: 0x%016lx\n", rd_root_size_off);
printf("rd_root_image off: 0x%016lx\n", rd_root_image_off);
#endif
/*
* Sanity check locations of db_* symbols
*/
if (rd_root_image_off < 0 || rd_root_image_off >= head.a.data_start)
errx(1, "%s: rd_root_image not in data segment?", file);
if (rd_root_size_off < 0 || rd_root_size_off >= head.a.data_start)
errx(1, "%s: rd_root_size not in data segment?", file);
}
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