mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-24 11:29:10 +00:00
360 lines
8.6 KiB
C
360 lines
8.6 KiB
C
/*
|
|
* Copyright (c) 1993 Paul Kranenburg
|
|
* 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. All advertising materials mentioning features or use of this software
|
|
* must display the following acknowledgement:
|
|
* This product includes software developed by Paul Kranenburg.
|
|
* 4. 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.
|
|
*
|
|
* $FreeBSD$
|
|
*/
|
|
|
|
#include <sys/param.h>
|
|
|
|
#include <stdlib.h>
|
|
|
|
#ifdef DYNAMIC
|
|
#include <sys/types.h>
|
|
#include <sys/syscall.h>
|
|
#include <a.out.h>
|
|
#include <string.h>
|
|
#include <sys/mman.h>
|
|
#include <link.h>
|
|
|
|
/* !!!
|
|
* This is gross, ld.so is a ZMAGIC a.out, but has `sizeof(hdr)' for
|
|
* an entry point and not at PAGSIZ as the N_*ADDR macros assume.
|
|
*/
|
|
#undef N_DATADDR
|
|
#define N_DATADDR(x) ((x).a_text)
|
|
|
|
#undef N_BSSADDR
|
|
#define N_BSSADDR(x) ((x).a_text + (x).a_data)
|
|
|
|
#ifndef N_GETMAGIC
|
|
#define N_GETMAGIC(x) ((x).a_magic)
|
|
#endif /* N_GETMAGIC */
|
|
|
|
#ifndef MAP_PRIVATE
|
|
#define MAP_PRIVATE MAP_COPY
|
|
#endif /* MAP_PRIVATE */
|
|
|
|
#ifndef MAP_FILE
|
|
#define MAP_FILE 0
|
|
#endif /* MAP_FILE */
|
|
|
|
#ifndef MAP_ANON
|
|
#define MAP_ANON 0
|
|
#endif /* MAP_ANON */
|
|
|
|
#ifdef DEBUG
|
|
/*
|
|
* We need these two because we are going to call them before the ld.so is
|
|
* finished (as a matter of fact before we know if it exists !) so we must
|
|
* provide these versions for them
|
|
*/
|
|
static char *_getenv();
|
|
static int _strncmp();
|
|
#endif /* DEBUG */
|
|
|
|
#ifndef LDSO
|
|
#define LDSO "/usr/libexec/ld.so"
|
|
#endif /* LDSO */
|
|
|
|
extern struct _dynamic _DYNAMIC;
|
|
static void __do_dynamic_link(char **argv);
|
|
#endif /* DYNAMIC */
|
|
|
|
int _callmain();
|
|
int errno;
|
|
static char empty[1];
|
|
char *__progname = empty;
|
|
char **environ;
|
|
|
|
/* Globals used by dlopen() and related functions in libc */
|
|
struct ld_entry *__ldso_entry;
|
|
int __ldso_version;
|
|
|
|
extern unsigned char etext;
|
|
extern unsigned char eprol asm ("eprol");
|
|
extern start() asm("start");
|
|
extern mcount() asm ("mcount");
|
|
extern int main(int argc, char **argv, char **envp);
|
|
int __syscall(int syscall,...);
|
|
#ifdef MCRT0
|
|
void monstartup(void *low, void *high);
|
|
#endif /* MCRT0 */
|
|
|
|
|
|
/*
|
|
* We need these system calls, but can't use library stubs because the are
|
|
* not accessible until we have done the ld.so stunt.
|
|
*/
|
|
|
|
#define _exit(v) \
|
|
__syscall(SYS_exit, (int)(v))
|
|
#define _open(name, f, m) \
|
|
__syscall(SYS_open, (const char *)(name), (int)(f), (int)(m))
|
|
#define _read(fd, s, n) \
|
|
__syscall(SYS_read, (int)(fd), (void *)(s), (size_t)(n))
|
|
#define _write(fd, s, n) \
|
|
__syscall(SYS_write, (int)(fd), (const void *)(s), (size_t)(n))
|
|
#define _mmap(addr, len, prot, flags, fd, off) \
|
|
(void *) __syscall(SYS_mmap, (void *)(addr), (size_t)(len), \
|
|
(int)(prot), (int)(flags), (int)(fd), 0, (off_t)(off))
|
|
|
|
#define _PUTNMSG(str, len) _write(2, (str), (len))
|
|
#define _PUTMSG(str) _PUTNMSG((str), sizeof (str) - 1)
|
|
#define _FATAL(str) ( _PUTMSG(str), _exit(1) )
|
|
|
|
|
|
int
|
|
start()
|
|
{
|
|
struct kframe {
|
|
int kargc;
|
|
char *kargv[1]; /* size depends on kargc */
|
|
char kargstr[1]; /* size varies */
|
|
char kenvstr[1]; /* size varies */
|
|
};
|
|
/*
|
|
* ALL REGISTER VARIABLES!!!
|
|
*/
|
|
register struct kframe *kfp;
|
|
register char **targv;
|
|
register char **argv;
|
|
extern void _mcleanup();
|
|
#ifdef DYNAMIC
|
|
volatile caddr_t x;
|
|
#endif
|
|
|
|
#ifdef lint
|
|
kfp = 0;
|
|
#else /* not lint */
|
|
/* just above the saved frame pointer */
|
|
asm ("lea 4(%%ebp), %0" : "=r" (kfp) );
|
|
#endif /* not lint */
|
|
for (argv = targv = &kfp->kargv[0]; *targv++; /* void */)
|
|
/* void */ ;
|
|
if (targv >= (char **)(*argv))
|
|
--targv;
|
|
environ = targv;
|
|
|
|
if (argv[0]) {
|
|
register char *s;
|
|
__progname = argv[0];
|
|
for (s=__progname; *s != '\0'; s++)
|
|
if (*s == '/')
|
|
__progname = s+1;
|
|
}
|
|
|
|
#ifdef DYNAMIC
|
|
/* ld(1) convention: if DYNAMIC = 0 then statically linked */
|
|
/* sometimes GCC is too smart/stupid for its own good */
|
|
x = (caddr_t)&_DYNAMIC;
|
|
if (x)
|
|
__do_dynamic_link(argv);
|
|
#endif /* DYNAMIC */
|
|
|
|
asm("eprol:");
|
|
|
|
#ifdef MCRT0
|
|
atexit(_mcleanup);
|
|
monstartup(&eprol, &etext);
|
|
#endif /* MCRT0 */
|
|
|
|
asm ("__callmain:"); /* Defined for the benefit of debuggers */
|
|
exit(main(kfp->kargc, argv, environ));
|
|
}
|
|
|
|
#ifdef DYNAMIC
|
|
static void
|
|
__do_dynamic_link(argv)
|
|
char **argv;
|
|
{
|
|
struct crt_ldso crt;
|
|
struct exec hdr;
|
|
char *ldso;
|
|
int (*entry)();
|
|
|
|
#ifdef DEBUG
|
|
/* Provision for alternate ld.so - security risk! */
|
|
if (!(ldso = _getenv("LDSO")))
|
|
#endif
|
|
ldso = LDSO;
|
|
|
|
crt.crt_ldfd = _open(ldso, 0, 0);
|
|
if (crt.crt_ldfd == -1) {
|
|
_PUTMSG("Couldn't open ");
|
|
_PUTMSG(LDSO);
|
|
_FATAL(".\n");
|
|
}
|
|
|
|
/* Read LDSO exec header */
|
|
if (_read(crt.crt_ldfd, &hdr, sizeof hdr) < sizeof hdr) {
|
|
_FATAL("Failure reading ld.so\n");
|
|
}
|
|
if ((N_GETMAGIC_NET(hdr) != ZMAGIC) && (N_GETMAGIC(hdr) != QMAGIC)) {
|
|
_FATAL("Bad magic: ld.so\n");
|
|
}
|
|
|
|
/* We use MAP_ANON */
|
|
crt.crt_dzfd = -1;
|
|
|
|
/* Map in ld.so */
|
|
crt.crt_ba = (int)_mmap(0, hdr.a_text,
|
|
PROT_READ|PROT_EXEC,
|
|
MAP_FILE|MAP_PRIVATE,
|
|
crt.crt_ldfd, N_TXTOFF(hdr));
|
|
if (crt.crt_ba == -1) {
|
|
_FATAL("Cannot map ld.so (text)\n");
|
|
}
|
|
|
|
/* Map in data segment of ld.so writable */
|
|
if ((int)_mmap((caddr_t)(crt.crt_ba+N_DATADDR(hdr)), hdr.a_data,
|
|
PROT_READ|PROT_WRITE,
|
|
MAP_FIXED|MAP_FILE|MAP_PRIVATE,
|
|
crt.crt_ldfd, N_DATOFF(hdr)) == -1) {
|
|
_FATAL("Cannot map ld.so (data)\n");
|
|
}
|
|
|
|
/* Map bss segment of ld.so zero */
|
|
if (hdr.a_bss && (int)_mmap((caddr_t)(crt.crt_ba+N_BSSADDR(hdr)),
|
|
hdr.a_bss,
|
|
PROT_READ|PROT_WRITE,
|
|
MAP_FIXED|MAP_ANON|MAP_PRIVATE,
|
|
crt.crt_dzfd, 0) == -1) {
|
|
_FATAL("Cannot map ld.so (bss)\n");
|
|
}
|
|
|
|
crt.crt_dp = &_DYNAMIC;
|
|
crt.crt_ep = environ;
|
|
crt.crt_bp = (caddr_t)_callmain;
|
|
crt.crt_prog = __progname;
|
|
crt.crt_ldso = ldso;
|
|
crt.crt_ldentry = NULL;
|
|
crt.crt_argv = argv;
|
|
|
|
entry = (int (*)())(crt.crt_ba + sizeof hdr);
|
|
__ldso_version = (*entry)(CRT_VERSION_BSD_5, &crt);
|
|
__ldso_entry = crt.crt_ldentry;
|
|
if (__ldso_version == -1 && __ldso_entry == NULL) {
|
|
/* If version 5 not recognised, try version 4 */
|
|
__ldso_version = (*entry)(CRT_VERSION_BSD_4, &crt);
|
|
__ldso_entry = crt.crt_ldentry;
|
|
if (__ldso_version == -1 && __ldso_entry == NULL) {
|
|
/* if version 4 not recognised, try version 3 */
|
|
__ldso_version = (*entry)(CRT_VERSION_BSD_3, &crt);
|
|
__ldso_entry = _DYNAMIC.d_entry;
|
|
}
|
|
}
|
|
if (__ldso_version == -1) {
|
|
_PUTMSG("ld.so failed");
|
|
if (__ldso_entry != NULL) {
|
|
const char *msg = (__ldso_entry->dlerror)();
|
|
if(msg != NULL) {
|
|
const char *endp;
|
|
_PUTMSG(": ");
|
|
for(endp = msg; *endp != '\0'; ++endp)
|
|
; /* Find the end */
|
|
_PUTNMSG(msg, endp - msg);
|
|
}
|
|
}
|
|
_FATAL("\n");
|
|
}
|
|
|
|
|
|
if (__ldso_version >= LDSO_VERSION_HAS_DLEXIT)
|
|
atexit(__ldso_entry->dlexit);
|
|
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Support routines
|
|
*/
|
|
|
|
#ifdef DEBUG
|
|
static int
|
|
_strncmp(s1, s2, n)
|
|
register char *s1, *s2;
|
|
register n;
|
|
{
|
|
|
|
if (n == 0)
|
|
return (0);
|
|
do {
|
|
if (*s1 != *s2++)
|
|
return (*(unsigned char *)s1 - *(unsigned char *)--s2);
|
|
if (*s1++ == 0)
|
|
break;
|
|
} while (--n != 0);
|
|
return (0);
|
|
}
|
|
|
|
static char *
|
|
_getenv(name)
|
|
register char *name;
|
|
{
|
|
extern char **environ;
|
|
register int len;
|
|
register char **P, *C;
|
|
|
|
for (C = name, len = 0; *C && *C != '='; ++C, ++len);
|
|
for (P = environ; *P; ++P)
|
|
if (!_strncmp(*P, name, len))
|
|
if (*(C = *P + len) == '=') {
|
|
return(++C);
|
|
}
|
|
return (char *)0;
|
|
}
|
|
|
|
#endif /* DEBUG */
|
|
|
|
asm(" ___syscall:");
|
|
asm(" popl %ecx");
|
|
asm(" popl %eax");
|
|
asm(" pushl %ecx");
|
|
asm(" .byte 0x9a");
|
|
asm(" .long 0");
|
|
asm(" .word 7");
|
|
asm(" pushl %ecx");
|
|
asm(" jc 1f");
|
|
asm(" ret");
|
|
asm(" 1:");
|
|
asm(" movl $-1,%eax");
|
|
asm(" ret");
|
|
|
|
#endif /* DYNAMIC */
|
|
|
|
|
|
/*
|
|
* Support routines
|
|
*/
|
|
|
|
#ifdef MCRT0
|
|
asm (" .text");
|
|
asm ("_eprol:");
|
|
#endif
|