HardenedBSD/sys/kern/imgact_gzip.c
Geoff Rehmet 65bbec73d7 - remove unnecessary #includes (I think a couple of redundant ones remain)
- excise some unused code (#if 0'd out - don't want to nuke it yet)
- fix problems with "make depend" - some macros were screwing it up
- get rid of some static local variables

There still seems to be a small reentrancy problem somewhere.
1994-10-11 11:29:17 +00:00

291 lines
7.3 KiB
C

/*
* Parts of this file are not covered by:
* ----------------------------------------------------------------------------
* "THE BEER-WARE LICENSE" (Revision 42):
* <phk@login.dknet.dk> wrote this file. As long as you retain this notice you
* can do whatever you want with this stuff. If we meet some day, and you think
* this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp
* ----------------------------------------------------------------------------
*
* $Id: imgact_gzip.c,v 1.7 1994/10/07 22:26:51 csgr Exp $
*
* This module handles execution of a.out files which have been run through
* "gzip -9".
*
* For now you need to use exactly this command to compress the binaries:
*
* gzip -9 -v < /bin/sh > /tmp/sh
*
* TODO:
* text-segments should be made R/O after being filled
* is the vm-stuff safe ?
* should handle the entire header of gzip'ed stuff.
* inflate isn't quite reentrant yet...
* error-handling is a mess...
* so is the rest...
* tidy up unnecesary includes
*/
#include <sys/param.h> /* some header file needs this first foo! */
#include <sys/exec.h>
#include <sys/imgact.h>
#include <sys/imgact_aout.h>
#include <sys/inflate.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mman.h>
#include <sys/resourcevar.h>
#include <sys/sysent.h>
#include <sys/systm.h>
#include <vm/vm.h>
#include <vm/vm_kern.h>
extern struct sysentvec aout_sysvec;
int
exec_gzip_imgact(iparams)
struct image_params *iparams;
{
int error,error2=0;
u_char *p = (u_char *) iparams->image_header;
struct gzip *gz;
struct gz_global gz_glbl;
/* If these four are not OK, it isn't a gzip file */
if (p[0] != 0x1f) return -1; /* 0 Simply magic */
if (p[1] != 0x8b) return -1; /* 1 Simply magic */
if (p[2] != 0x08) return -1; /* 2 Compression method */
if (p[9] != 0x03) return -1; /* 9 OS compressed on */
/* If this one contains anything but a comment or a filename
* marker, we don't want to chew on it
*/
if (p[3] & ~(0x18)) return ENOEXEC; /* 3 Flags */
/* These are of no use to us */
/* 4-7 Timestamp */
/* 8 Extra flags */
gz = malloc(sizeof *gz,M_GZIP,M_NOWAIT);
if (!gz)
return ENOMEM;
bzero(gz,sizeof *gz); /* waste of time ? */
gz->gz_slide = malloc(WSIZE,M_TEMP,M_NOWAIT);
if (!gz->gz_slide) {
free(gz,M_GZIP);
return ENOMEM;
}
gz->ip = iparams;
gz->error = ENOEXEC;
gz->idx = 10;
if (p[3] & 0x08) { /* skip a filename */
while (p[gz->idx++])
if (gz->idx >= PAGE_SIZE)
goto done;
}
if (p[3] & 0x10) { /* skip a comment */
while (p[gz->idx++])
if (gz->idx >= PAGE_SIZE)
goto done;
}
gz->len = gz->ip->attr->va_size;
gz->error = 0;
error = inflate(gz, &gz_glbl);
if (gz->inbuf) {
error2 =
vm_deallocate(kernel_map, (vm_offset_t)gz->inbuf, PAGE_SIZE);
}
if (gz->error || error || error2) {
printf("Output=%lu ",gz->output);
printf("Inflate_error=%d gz->error=%d error2=%d where=%d\n",
error,gz->error,error2,gz->where);
if (gz->error)
goto done;
if (error) {
gz->error = ENOEXEC;
goto done;
}
if (error2) {
gz->error = error2;
goto done;
}
}
done:
error = gz->error;
free(gz->gz_slide,M_TEMP);
free(gz,M_GZIP);
return error;
}
int
do_aout_hdr(struct gzip *gz)
{
int error;
struct vmspace *vmspace = gz->ip->proc->p_vmspace;
u_long vmaddr;
/*
* Set file/virtual offset based on a.out variant.
* We do two cases: host byte order and network byte order
* (for NetBSD compatibility)
*/
switch ((int)(gz->a_out.a_magic & 0xffff)) {
case ZMAGIC:
gz->virtual_offset = 0;
if (gz->a_out.a_text) {
gz->file_offset = NBPG;
} else {
/* Bill's "screwball mode" */
gz->file_offset = 0;
}
break;
case QMAGIC:
gz->virtual_offset = NBPG;
gz->file_offset = 0;
break;
default:
/* NetBSD compatibility */
switch ((int)(ntohl(gz->a_out.a_magic) & 0xffff)) {
case ZMAGIC:
case QMAGIC:
gz->virtual_offset = NBPG;
gz->file_offset = 0;
break;
default:
gz->where = __LINE__;
return (-1);
}
}
gz->bss_size = roundup(gz->a_out.a_bss, NBPG);
/*
* Check various fields in header for validity/bounds.
*/
if (/* entry point must lay with text region */
gz->a_out.a_entry < gz->virtual_offset ||
gz->a_out.a_entry >= gz->virtual_offset + gz->a_out.a_text ||
/* text and data size must each be page rounded */
gz->a_out.a_text % NBPG ||
gz->a_out.a_data % NBPG) {
gz->where = __LINE__;
return (-1);
}
/*
* text/data/bss must not exceed limits
*/
if (/* text can't exceed maximum text size */
gz->a_out.a_text > MAXTSIZ ||
/* data + bss can't exceed maximum data size */
gz->a_out.a_data + gz->bss_size > MAXDSIZ ||
/* data + bss can't exceed rlimit */
gz->a_out.a_data + gz->bss_size >
gz->ip->proc->p_rlimit[RLIMIT_DATA].rlim_cur) {
gz->where = __LINE__;
return (ENOMEM);
}
/* Find out how far we should go */
gz->file_end = gz->file_offset + gz->a_out.a_text + gz->a_out.a_data;
/* copy in arguments and/or environment from old process */
error = exec_extract_strings(gz->ip);
if (error) {
gz->where = __LINE__;
return (error);
}
/*
* Destroy old process VM and create a new one (with a new stack)
*/
exec_new_vmspace(gz->ip);
vmaddr = gz->virtual_offset;
error = vm_mmap(&vmspace->vm_map, /* map */
&vmaddr, /* address */
gz->a_out.a_text, /* size */
VM_PROT_READ | VM_PROT_EXECUTE | VM_PROT_WRITE, /* protection */
VM_PROT_READ | VM_PROT_EXECUTE | VM_PROT_WRITE,
MAP_ANON | MAP_FIXED, /* flags */
0, /* vnode */
0); /* offset */
if (error) {
gz->where = __LINE__;
return (error);
}
vmaddr = gz->virtual_offset + gz->a_out.a_text;
/*
* Map data read/write (if text is 0, assume text is in data area
* [Bill's screwball mode])
*/
error = vm_mmap(&vmspace->vm_map,
&vmaddr,
gz->a_out.a_data,
VM_PROT_READ | VM_PROT_WRITE | (gz->a_out.a_text ? 0 : VM_PROT_EXECUTE),
VM_PROT_ALL, MAP_ANON | MAP_FIXED,
0,
0);
if (error) {
gz->where = __LINE__;
return (error);
}
/*
* Allocate demand-zeroed area for uninitialized data
* "bss" = 'block started by symbol' - named after the IBM 7090
* instruction of the same name.
*/
vmaddr = gz->virtual_offset + gz->a_out.a_text + gz->a_out.a_data;
error = vm_allocate(&vmspace->vm_map, &vmaddr, gz->bss_size, FALSE);
if (error) {
gz->where = __LINE__;
return (error);
}
/* Fill in process VM information */
vmspace->vm_tsize = gz->a_out.a_text >> PAGE_SHIFT;
vmspace->vm_dsize = (gz->a_out.a_data + gz->bss_size) >> PAGE_SHIFT;
vmspace->vm_taddr = (caddr_t) gz->virtual_offset;
vmspace->vm_daddr = (caddr_t) gz->virtual_offset + gz->a_out.a_text;
/* Fill in image_params */
gz->ip->interpreted = 0;
gz->ip->entry_addr = gz->a_out.a_entry;
gz->ip->proc->p_sysent = &aout_sysvec;
return 0;
}
/*
* Tell kern_execve.c about it, with a little help from the linker.
* Since `const' objects end up in the text segment, TEXT_SET is the
* correct directive to use.
*/
static const struct execsw gzip_execsw = { exec_gzip_imgact, "gzip" };
TEXT_SET(execsw_set, gzip_execsw);