freebsd-dev/usr.sbin/btxld/btxld.c
Christian Brueffer 419749b63a In puthdr(), start the ELF .data section on a new page, as this is
what btxldr expects (.set MEM_DATA,start+0x1000 in btxldr.S).

This makes resulting ELF binaries bootable with grub, gptboot and boot2.

PR:		153801
Submitted by:	Gleb Kurtsou <gleb.kurtsou at gmail.com>
Tested by:	Ruben Kerkhof <ruben at rubenkerkhof.com>
Glanced at by:	jhb, peter
MFC after:	1 month
2014-02-25 17:13:42 +00:00

576 lines
14 KiB
C

/*
* Copyright (c) 1998 Robert Nordier
* 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 AND CONTRIBUTORS``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 OR CONTRIBUTORS
* 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.
*/
#ifndef lint
static const char rcsid[] =
"$FreeBSD$";
#endif /* not lint */
#include <sys/param.h>
#include <sys/endian.h>
#include <sys/stat.h>
#include <sys/mman.h>
/* XXX make this work as an i386/amd64 cross-tool */
#include <machine/exec.h>
#undef __LDPGSZ
#define __LDPGSZ 4096
#include <netinet/in.h>
#include <a.out.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "btx.h"
#include "elfh.h"
#define BTX_PATH "/sys/boot/i386/btx"
#define I_LDR 0 /* BTX loader */
#define I_BTX 1 /* BTX kernel */
#define I_CLNT 2 /* Client program */
#define F_BIN 0 /* Binary */
#define F_AOUT 1 /* ZMAGIC a.out */
#define F_ELF 2 /* 32-bit ELF */
#define F_CNT 3 /* Number of formats */
#define IMPURE 1 /* Writable text */
#define MAXU32 0xffffffff /* Maximum unsigned 32-bit quantity */
#define align(x, y) (((x) + (y) - 1) & ~((y) - 1))
struct hdr {
uint32_t fmt; /* Format */
uint32_t flags; /* Bit flags */
uint32_t size; /* Size of file */
uint32_t text; /* Size of text segment */
uint32_t data; /* Size of data segment */
uint32_t bss; /* Size of bss segment */
uint32_t org; /* Program origin */
uint32_t entry; /* Program entry point */
};
static const char *const fmtlist[] = {"bin", "aout", "elf"};
static const char binfo[] =
"kernel: ver=%u.%02u size=%x load=%x entry=%x map=%uM "
"pgctl=%x:%x\n";
static const char cinfo[] =
"client: fmt=%s size=%x text=%x data=%x bss=%x entry=%x\n";
static const char oinfo[] =
"output: fmt=%s size=%x text=%x data=%x org=%x entry=%x\n";
static const char *lname =
BTX_PATH "/btxldr/btxldr"; /* BTX loader */
static const char *bname =
BTX_PATH "/btx/btx"; /* BTX kernel */
static const char *oname =
"a.out"; /* Output filename */
static int ppage = -1; /* First page present */
static int wpage = -1; /* First page writable */
static unsigned int format; /* Output format */
static uint32_t centry; /* Client entry address */
static uint32_t lentry; /* Loader entry address */
static int Eflag; /* Client entry option */
static int quiet; /* Inhibit warnings */
static int verbose; /* Display information */
static const char *tname; /* Temporary output file */
static const char *fname; /* Current input file */
static void cleanup(void);
static void btxld(const char *);
static void getbtx(int, struct btx_hdr *);
static void gethdr(int, struct hdr *);
static void puthdr(int, struct hdr *);
static void copy(int, int, size_t, off_t);
static size_t readx(int, void *, size_t, off_t);
static void writex(int, const void *, size_t);
static void seekx(int, off_t);
static unsigned int optfmt(const char *);
static uint32_t optaddr(const char *);
static int optpage(const char *, int);
static void Warn(const char *, const char *, ...);
static void usage(void);
/*
* A link editor for BTX clients.
*/
int
main(int argc, char *argv[])
{
int c;
while ((c = getopt(argc, argv, "qvb:E:e:f:l:o:P:W:")) != -1)
switch (c) {
case 'q':
quiet = 1;
break;
case 'v':
verbose = 1;
break;
case 'b':
bname = optarg;
break;
case 'E':
centry = optaddr(optarg);
Eflag = 1;
break;
case 'e':
lentry = optaddr(optarg);
break;
case 'f':
format = optfmt(optarg);
break;
case 'l':
lname = optarg;
break;
case 'o':
oname = optarg;
break;
case 'P':
ppage = optpage(optarg, 1);
break;
case 'W':
wpage = optpage(optarg, BTX_MAXCWR);
break;
default:
usage();
}
argc -= optind;
argv += optind;
if (argc != 1)
usage();
atexit(cleanup);
btxld(*argv);
return 0;
}
/*
* Clean up after errors.
*/
static void
cleanup(void)
{
if (tname)
remove(tname);
}
/*
* Read the input files; write the output file; display information.
*/
static void
btxld(const char *iname)
{
char name[FILENAME_MAX];
struct btx_hdr btx, btxle;
struct hdr ihdr, ohdr;
unsigned int ldr_size, cwr;
int fdi[3], fdo, i;
ldr_size = 0;
for (i = I_LDR; i <= I_CLNT; i++) {
fname = i == I_LDR ? lname : i == I_BTX ? bname : iname;
if ((fdi[i] = open(fname, O_RDONLY)) == -1)
err(2, "%s", fname);
switch (i) {
case I_LDR:
gethdr(fdi[i], &ihdr);
if (ihdr.fmt != F_BIN)
Warn(fname, "Loader format is %s; processing as %s",
fmtlist[ihdr.fmt], fmtlist[F_BIN]);
ldr_size = ihdr.size;
break;
case I_BTX:
getbtx(fdi[i], &btx);
break;
case I_CLNT:
gethdr(fdi[i], &ihdr);
if (ihdr.org && ihdr.org != BTX_PGSIZE)
Warn(fname,
"Client origin is 0x%x; expecting 0 or 0x%x",
ihdr.org, BTX_PGSIZE);
}
}
memset(&ohdr, 0, sizeof(ohdr));
ohdr.fmt = format;
ohdr.text = ldr_size;
ohdr.data = btx.btx_textsz + ihdr.size;
ohdr.org = lentry;
ohdr.entry = lentry;
cwr = 0;
if (wpage > 0 || (wpage == -1 && !(ihdr.flags & IMPURE))) {
if (wpage > 0)
cwr = wpage;
else {
cwr = howmany(ihdr.text, BTX_PGSIZE);
if (cwr > BTX_MAXCWR)
cwr = BTX_MAXCWR;
}
}
if (ppage > 0 || (ppage && wpage && ihdr.org >= BTX_PGSIZE)) {
btx.btx_flags |= BTX_MAPONE;
if (!cwr)
cwr++;
}
btx.btx_pgctl -= cwr;
btx.btx_entry = Eflag ? centry : ihdr.entry;
if ((size_t)snprintf(name, sizeof(name), "%s.tmp", oname) >= sizeof(name))
errx(2, "%s: Filename too long", oname);
if ((fdo = open(name, O_CREAT | O_TRUNC | O_WRONLY, 0666)) == -1)
err(2, "%s", name);
if (!(tname = strdup(name)))
err(2, NULL);
puthdr(fdo, &ohdr);
for (i = I_LDR; i <= I_CLNT; i++) {
fname = i == I_LDR ? lname : i == I_BTX ? bname : iname;
switch (i) {
case I_LDR:
copy(fdi[i], fdo, ldr_size, 0);
seekx(fdo, ohdr.size += ohdr.text);
break;
case I_BTX:
btxle = btx;
btxle.btx_pgctl = htole16(btxle.btx_pgctl);
btxle.btx_textsz = htole16(btxle.btx_textsz);
btxle.btx_entry = htole32(btxle.btx_entry);
writex(fdo, &btxle, sizeof(btxle));
copy(fdi[i], fdo, btx.btx_textsz - sizeof(btx),
sizeof(btx));
break;
case I_CLNT:
copy(fdi[i], fdo, ihdr.size, 0);
if (ftruncate(fdo, ohdr.size += ohdr.data))
err(2, "%s", tname);
}
if (close(fdi[i]))
err(2, "%s", fname);
}
if (close(fdo))
err(2, "%s", tname);
if (rename(tname, oname))
err(2, "%s: Can't rename to %s", tname, oname);
tname = NULL;
if (verbose) {
printf(binfo, btx.btx_majver, btx.btx_minver, btx.btx_textsz,
BTX_ORIGIN(btx), BTX_ENTRY(btx), BTX_MAPPED(btx) *
BTX_PGSIZE / 0x100000, !!(btx.btx_flags & BTX_MAPONE),
BTX_MAPPED(btx) - btx.btx_pgctl - BTX_PGBASE /
BTX_PGSIZE - BTX_MAPPED(btx) * 4 / BTX_PGSIZE);
printf(cinfo, fmtlist[ihdr.fmt], ihdr.size, ihdr.text,
ihdr.data, ihdr.bss, ihdr.entry);
printf(oinfo, fmtlist[ohdr.fmt], ohdr.size, ohdr.text,
ohdr.data, ohdr.org, ohdr.entry);
}
}
/*
* Read BTX file header.
*/
static void
getbtx(int fd, struct btx_hdr * btx)
{
if (readx(fd, btx, sizeof(*btx), 0) != sizeof(*btx) ||
btx->btx_magic[0] != BTX_MAG0 ||
btx->btx_magic[1] != BTX_MAG1 ||
btx->btx_magic[2] != BTX_MAG2)
errx(1, "%s: Not a BTX kernel", fname);
btx->btx_pgctl = le16toh(btx->btx_pgctl);
btx->btx_textsz = le16toh(btx->btx_textsz);
btx->btx_entry = le32toh(btx->btx_entry);
}
/*
* Get file size and read a.out or ELF header.
*/
static void
gethdr(int fd, struct hdr *hdr)
{
struct stat sb;
const struct exec *ex;
const Elf32_Ehdr *ee;
const Elf32_Phdr *ep;
void *p;
unsigned int fmt, x, n, i;
memset(hdr, 0, sizeof(*hdr));
if (fstat(fd, &sb))
err(2, "%s", fname);
if (sb.st_size > MAXU32)
errx(1, "%s: Too big", fname);
hdr->size = sb.st_size;
if (!hdr->size)
return;
if ((p = mmap(NULL, hdr->size, PROT_READ, MAP_SHARED, fd,
0)) == MAP_FAILED)
err(2, "%s", fname);
for (fmt = F_CNT - 1; !hdr->fmt && fmt; fmt--)
switch (fmt) {
case F_AOUT:
ex = p;
if (hdr->size >= sizeof(struct exec) && !N_BADMAG(*ex)) {
hdr->fmt = fmt;
x = N_GETMAGIC(*ex);
if (x == OMAGIC || x == NMAGIC) {
if (x == NMAGIC)
Warn(fname, "Treating %s NMAGIC as OMAGIC",
fmtlist[fmt]);
hdr->flags |= IMPURE;
}
hdr->text = le32toh(ex->a_text);
hdr->data = le32toh(ex->a_data);
hdr->bss = le32toh(ex->a_bss);
hdr->entry = le32toh(ex->a_entry);
if (le32toh(ex->a_entry) >= BTX_PGSIZE)
hdr->org = BTX_PGSIZE;
}
break;
case F_ELF:
ee = p;
if (hdr->size >= sizeof(Elf32_Ehdr) && IS_ELF(*ee)) {
hdr->fmt = fmt;
for (n = i = 0; i < le16toh(ee->e_phnum); i++) {
ep = (void *)((uint8_t *)p + le32toh(ee->e_phoff) +
le16toh(ee->e_phentsize) * i);
if (le32toh(ep->p_type) == PT_LOAD)
switch (n++) {
case 0:
hdr->text = le32toh(ep->p_filesz);
hdr->org = le32toh(ep->p_paddr);
if (le32toh(ep->p_flags) & PF_W)
hdr->flags |= IMPURE;
break;
case 1:
hdr->data = le32toh(ep->p_filesz);
hdr->bss = le32toh(ep->p_memsz) -
le32toh(ep->p_filesz);
break;
case 2:
Warn(fname,
"Ignoring extra %s PT_LOAD segments",
fmtlist[fmt]);
}
}
hdr->entry = le32toh(ee->e_entry);
}
}
if (munmap(p, hdr->size))
err(2, "%s", fname);
}
/*
* Write a.out or ELF header.
*/
static void
puthdr(int fd, struct hdr *hdr)
{
struct exec ex;
struct elfh eh;
switch (hdr->fmt) {
case F_AOUT:
memset(&ex, 0, sizeof(ex));
N_SETMAGIC(ex, ZMAGIC, MID_I386, 0);
hdr->text = N_ALIGN(ex, hdr->text);
ex.a_text = htole32(hdr->text);
hdr->data = N_ALIGN(ex, hdr->data);
ex.a_data = htole32(hdr->data);
ex.a_entry = htole32(hdr->entry);
writex(fd, &ex, sizeof(ex));
hdr->size = N_ALIGN(ex, sizeof(ex));
seekx(fd, hdr->size);
break;
case F_ELF:
eh = elfhdr;
eh.e.e_entry = htole32(hdr->entry);
eh.p[0].p_vaddr = eh.p[0].p_paddr = htole32(hdr->org);
eh.p[0].p_filesz = eh.p[0].p_memsz = htole32(hdr->text);
eh.p[1].p_offset = htole32(le32toh(eh.p[0].p_offset) +
le32toh(eh.p[0].p_filesz));
eh.p[1].p_vaddr = eh.p[1].p_paddr =
htole32(align(le32toh(eh.p[0].p_paddr) + le32toh(eh.p[0].p_memsz),
4096));
eh.p[1].p_filesz = eh.p[1].p_memsz = htole32(hdr->data);
eh.sh[2].sh_addr = eh.p[0].p_vaddr;
eh.sh[2].sh_offset = eh.p[0].p_offset;
eh.sh[2].sh_size = eh.p[0].p_filesz;
eh.sh[3].sh_addr = eh.p[1].p_vaddr;
eh.sh[3].sh_offset = eh.p[1].p_offset;
eh.sh[3].sh_size = eh.p[1].p_filesz;
writex(fd, &eh, sizeof(eh));
hdr->size = sizeof(eh);
}
}
/*
* Safe copy from input file to output file.
*/
static void
copy(int fdi, int fdo, size_t nbyte, off_t offset)
{
char buf[8192];
size_t n;
while (nbyte) {
if ((n = sizeof(buf)) > nbyte)
n = nbyte;
if (readx(fdi, buf, n, offset) != n)
errx(2, "%s: Short read", fname);
writex(fdo, buf, n);
nbyte -= n;
offset = -1;
}
}
/*
* Safe read from input file.
*/
static size_t
readx(int fd, void *buf, size_t nbyte, off_t offset)
{
ssize_t n;
if (offset != -1 && lseek(fd, offset, SEEK_SET) != offset)
err(2, "%s", fname);
if ((n = read(fd, buf, nbyte)) == -1)
err(2, "%s", fname);
return n;
}
/*
* Safe write to output file.
*/
static void
writex(int fd, const void *buf, size_t nbyte)
{
ssize_t n;
if ((n = write(fd, buf, nbyte)) == -1)
err(2, "%s", tname);
if ((size_t)n != nbyte)
errx(2, "%s: Short write", tname);
}
/*
* Safe seek in output file.
*/
static void
seekx(int fd, off_t offset)
{
if (lseek(fd, offset, SEEK_SET) != offset)
err(2, "%s", tname);
}
/*
* Convert an option argument to a format code.
*/
static unsigned int
optfmt(const char *arg)
{
unsigned int i;
for (i = 0; i < F_CNT && strcmp(arg, fmtlist[i]); i++);
if (i == F_CNT)
errx(1, "%s: Unknown format", arg);
return i;
}
/*
* Convert an option argument to an address.
*/
static uint32_t
optaddr(const char *arg)
{
char *s;
unsigned long x;
errno = 0;
x = strtoul(arg, &s, 0);
if (errno || !*arg || *s || x > MAXU32)
errx(1, "%s: Illegal address", arg);
return x;
}
/*
* Convert an option argument to a page number.
*/
static int
optpage(const char *arg, int hi)
{
char *s;
long x;
errno = 0;
x = strtol(arg, &s, 0);
if (errno || !*arg || *s || x < 0 || x > hi)
errx(1, "%s: Illegal page number", arg);
return x;
}
/*
* Display a warning.
*/
static void
Warn(const char *locus, const char *fmt, ...)
{
va_list ap;
char *s;
if (!quiet) {
asprintf(&s, "%s: Warning: %s", locus, fmt);
va_start(ap, fmt);
vwarnx(s, ap);
va_end(ap);
free(s);
}
}
/*
* Display usage information.
*/
static void
usage(void)
{
fprintf(stderr, "%s\n%s\n",
"usage: btxld [-qv] [-b file] [-E address] [-e address] [-f format]",
" [-l file] [-o filename] [-P page] [-W page] file");
exit(1);
}