2 * ----------------------------------------------------------------------------
3 * "THE BEER-WARE LICENSE" (Revision 42):
4 * <phk@login.dkuug.dk> wrote this file. As long as you retain this notice you
5 * can do whatever you want with this stuff. If we meet some day, and you think
6 * this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp
7 * ----------------------------------------------------------------------------
9 * $FreeBSD: src/sys/kern/imgact_gzip.c,v 1.40.2.1 2001/11/03 01:41:08 ps Exp $
10 * $DragonFly: src/sys/kern/imgact_gzip.c,v 1.5 2004/01/20 18:41:51 dillon Exp $
12 * This module handles execution of a.out files which have been run through
13 * "gzip". This saves diskspace, but wastes cpu-cycles and VM.
16 * text-segments should be made R/O after being filled
17 * is the vm-stuff safe ?
18 * should handle the entire header of gzip'ed stuff.
19 * inflate isn't quite reentrant yet...
20 * error-handling is a mess...
22 * tidy up unnecesary includes
25 #include <sys/param.h>
27 #include <sys/imgact.h>
28 #include <sys/imgact_aout.h>
29 #include <sys/kernel.h>
32 #include <sys/resourcevar.h>
33 #include <sys/sysent.h>
34 #include <sys/systm.h>
35 #include <sys/vnode.h>
36 #include <sys/inflate.h>
39 #include <vm/vm_param.h>
42 #include <vm/vm_map.h>
43 #include <vm/vm_kern.h>
44 #include <vm/vm_extern.h>
47 struct image_params
*ip
;
57 u_long virtual_offset
, file_offset
, file_end
, bss_size
;
60 static int exec_gzip_imgact (struct image_params
*imgp
);
61 static int NextByte (void *vp
);
62 static int do_aout_hdr (struct imgact_gzip
*);
63 static int Flush (void *vp
, u_char
*, u_long siz
);
66 exec_gzip_imgact(imgp
)
67 struct image_params
*imgp
;
69 int error
, error2
= 0;
70 const u_char
*p
= (const u_char
*) imgp
->image_header
;
71 struct imgact_gzip igz
;
73 struct vmspace
*vmspace
;
75 /* If these four are not OK, it isn't a gzip file */
77 return -1; /* 0 Simply magic */
79 return -1; /* 1 Simply magic */
81 return -1; /* 2 Compression method */
83 return -1; /* 9 OS compressed on */
86 * If this one contains anything but a comment or a filename marker,
87 * we don't want to chew on it
90 return ENOEXEC
; /* 3 Flags */
92 /* These are of no use to us */
96 bzero(&igz
, sizeof igz
);
97 bzero(&infl
, sizeof infl
);
98 infl
.gz_private
= (void *) &igz
;
99 infl
.gz_input
= NextByte
;
100 infl
.gz_output
= Flush
;
105 if (p
[3] & 0x08) { /* skip a filename */
107 if (igz
.idx
>= PAGE_SIZE
)
110 if (p
[3] & 0x10) { /* skip a comment */
112 if (igz
.idx
>= PAGE_SIZE
)
115 igz
.len
= imgp
->attr
->va_size
;
117 error
= inflate(&infl
);
120 * The unzipped file may not even have been long enough to contain
121 * a header giving Flush() a chance to return error. Check for this.
123 if ( !igz
.gotheader
)
127 vmspace
= imgp
->proc
->p_vmspace
;
128 error
= vm_map_protect(&vmspace
->vm_map
,
129 (vm_offset_t
) vmspace
->vm_taddr
,
130 (vm_offset_t
) (vmspace
->vm_taddr
+
131 (vmspace
->vm_tsize
<< PAGE_SHIFT
)) ,
132 VM_PROT_READ
|VM_PROT_EXECUTE
,0);
137 vm_map_remove(kernel_map
, (vm_offset_t
) igz
.inbuf
,
138 (vm_offset_t
) igz
.inbuf
+ PAGE_SIZE
);
140 if (igz
.error
|| error
|| error2
) {
141 printf("Output=%lu ", igz
.output
);
142 printf("Inflate_error=%d igz.error=%d error2=%d where=%d\n",
143 error
, igz
.error
, error2
, igz
.where
);
155 do_aout_hdr(struct imgact_gzip
* gz
)
158 struct vmspace
*vmspace
;
162 * Set file/virtual offset based on a.out variant. We do two cases:
163 * host byte order and network byte order (for NetBSD compatibility)
165 switch ((int) (gz
->a_out
.a_magic
& 0xffff)) {
167 gz
->virtual_offset
= 0;
168 if (gz
->a_out
.a_text
) {
169 gz
->file_offset
= PAGE_SIZE
;
171 /* Bill's "screwball mode" */
176 gz
->virtual_offset
= PAGE_SIZE
;
180 /* NetBSD compatibility */
181 switch ((int) (ntohl(gz
->a_out
.a_magic
) & 0xffff)) {
184 gz
->virtual_offset
= PAGE_SIZE
;
188 gz
->where
= __LINE__
;
193 gz
->bss_size
= roundup(gz
->a_out
.a_bss
, PAGE_SIZE
);
196 * Check various fields in header for validity/bounds.
198 if ( /* entry point must lay with text region */
199 gz
->a_out
.a_entry
< gz
->virtual_offset
||
200 gz
->a_out
.a_entry
>= gz
->virtual_offset
+ gz
->a_out
.a_text
||
202 /* text and data size must each be page rounded */
203 gz
->a_out
.a_text
& PAGE_MASK
|| gz
->a_out
.a_data
& PAGE_MASK
) {
204 gz
->where
= __LINE__
;
208 * text/data/bss must not exceed limits
210 if ( /* text can't exceed maximum text size */
211 gz
->a_out
.a_text
> maxtsiz
||
213 /* data + bss can't exceed rlimit */
214 gz
->a_out
.a_data
+ gz
->bss_size
>
215 gz
->ip
->proc
->p_rlimit
[RLIMIT_DATA
].rlim_cur
) {
216 gz
->where
= __LINE__
;
219 /* Find out how far we should go */
220 gz
->file_end
= gz
->file_offset
+ gz
->a_out
.a_text
+ gz
->a_out
.a_data
;
223 * Destroy old process VM and create a new one (with a new stack)
225 exec_new_vmspace(gz
->ip
, NULL
);
227 vmspace
= gz
->ip
->proc
->p_vmspace
;
229 vmaddr
= gz
->virtual_offset
;
231 error
= vm_mmap(&vmspace
->vm_map
,
233 gz
->a_out
.a_text
+ gz
->a_out
.a_data
,
234 VM_PROT_ALL
, VM_PROT_ALL
, MAP_ANON
| MAP_FIXED
,
239 gz
->where
= __LINE__
;
243 if (gz
->bss_size
!= 0) {
245 * Allocate demand-zeroed area for uninitialized data.
246 * "bss" = 'block started by symbol' - named after the
247 * IBM 7090 instruction of the same name.
249 vmaddr
= gz
->virtual_offset
+ gz
->a_out
.a_text
+
251 error
= vm_map_find(&vmspace
->vm_map
,
256 FALSE
, VM_PROT_ALL
, VM_PROT_ALL
, 0);
258 gz
->where
= __LINE__
;
262 /* Fill in process VM information */
263 vmspace
->vm_tsize
= gz
->a_out
.a_text
>> PAGE_SHIFT
;
264 vmspace
->vm_dsize
= (gz
->a_out
.a_data
+ gz
->bss_size
) >> PAGE_SHIFT
;
265 vmspace
->vm_taddr
= (caddr_t
) (uintptr_t) gz
->virtual_offset
;
266 vmspace
->vm_daddr
= (caddr_t
) (uintptr_t)
267 (gz
->virtual_offset
+ gz
->a_out
.a_text
);
269 /* Fill in image_params */
270 gz
->ip
->interpreted
= 0;
271 gz
->ip
->entry_addr
= gz
->a_out
.a_entry
;
273 gz
->ip
->proc
->p_sysent
= &aout_sysvec
;
282 struct imgact_gzip
*igz
= (struct imgact_gzip
*) vp
;
284 if (igz
->idx
>= igz
->len
) {
285 igz
->where
= __LINE__
;
288 if (igz
->inbuf
&& igz
->idx
< (igz
->offset
+ PAGE_SIZE
)) {
289 return igz
->inbuf
[(igz
->idx
++) - igz
->offset
];
292 error
= vm_map_remove(kernel_map
, (vm_offset_t
) igz
->inbuf
,
293 (vm_offset_t
) igz
->inbuf
+ PAGE_SIZE
);
295 igz
->where
= __LINE__
;
300 igz
->offset
= igz
->idx
& ~PAGE_MASK
;
302 error
= vm_mmap(kernel_map
, /* map */
303 (vm_offset_t
*) & igz
->inbuf
, /* address */
304 PAGE_SIZE
, /* size */
305 VM_PROT_READ
, /* protection */
306 VM_PROT_READ
, /* max protection */
308 (caddr_t
) igz
->ip
->vp
, /* vnode */
309 igz
->offset
); /* offset */
311 igz
->where
= __LINE__
;
315 return igz
->inbuf
[(igz
->idx
++) - igz
->offset
];
319 Flush(void *vp
, u_char
* ptr
, u_long siz
)
321 struct imgact_gzip
*gz
= (struct imgact_gzip
*) vp
;
325 /* First, find a a.out-header */
326 if (gz
->output
< sizeof gz
->a_out
) {
327 q
= (u_char
*) & gz
->a_out
;
328 i
= min(siz
, sizeof gz
->a_out
- gz
->output
);
329 bcopy(p
, q
+ gz
->output
, i
);
333 if (gz
->output
== sizeof gz
->a_out
) {
338 gz
->where
= __LINE__
;
342 gz
->where
= __LINE__
;
346 if (gz
->file_offset
== 0) {
347 q
= (u_char
*) (uintptr_t) gz
->virtual_offset
;
348 copyout(&gz
->a_out
, q
, sizeof gz
->a_out
);
352 /* Skip over zero-padded first PAGE if needed */
353 if (gz
->output
< gz
->file_offset
&&
354 gz
->output
+ siz
> gz
->file_offset
) {
355 i
= min(siz
, gz
->file_offset
- gz
->output
);
360 if (gz
->output
>= gz
->file_offset
&& gz
->output
< gz
->file_end
) {
361 i
= min(siz
, gz
->file_end
- gz
->output
);
362 q
= (u_char
*) (uintptr_t)
363 (gz
->virtual_offset
+ gz
->output
- gz
->file_offset
);
375 * Tell kern_execve.c about it, with a little help from the linker.
377 static struct execsw gzip_execsw
= {exec_gzip_imgact
, "gzip"};
378 EXEC_SET(execgzip
, gzip_execsw
);