0
|
1 /* Unexec for DEC alpha. schoepf@sc.ZIB-Berlin.DE (Rainer Schoepf).
|
|
2
|
|
3 Copyright (C) 1994 Free Software Foundation, Inc.
|
|
4
|
|
5 This file is part of GNU Emacs.
|
|
6
|
|
7 GNU Emacs is free software; you can redistribute it and/or modify
|
|
8 it under the terms of the GNU General Public License as published by
|
|
9 the Free Software Foundation; either version 2, or (at your option)
|
|
10 any later version.
|
|
11
|
|
12 GNU Emacs is distributed in the hope that it will be useful,
|
|
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
15 GNU General Public License for more details.
|
|
16
|
|
17 You should have received a copy of the GNU General Public License
|
|
18 along with GNU Emacs; see the file COPYING. If not, write to
|
|
19 the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
|
|
20 Boston, MA 02111-1307, USA. */
|
|
21
|
|
22 /* Synched up with: FSF 19.31. */
|
|
23
|
|
24
|
|
25 #include <config.h>
|
173
|
26 #include <stdlib.h>
|
|
27 #include <string.h>
|
|
28 #include <unistd.h>
|
0
|
29 #include <sys/types.h>
|
|
30 #include <sys/file.h>
|
|
31 #include <sys/stat.h>
|
|
32 #include <sys/mman.h>
|
|
33 #include <stdio.h>
|
|
34 #include <varargs.h>
|
|
35 #include <filehdr.h>
|
|
36 #include <aouthdr.h>
|
|
37 #include <scnhdr.h>
|
|
38 #include <syms.h>
|
|
39
|
173
|
40 static void fatal_unexec (char *, char *);
|
|
41 static void mark_x (char *);
|
0
|
42
|
|
43 #define READ(_fd, _buffer, _size, _error_message, _error_arg) \
|
|
44 errno = EEOF; \
|
|
45 if (read (_fd, _buffer, _size) != _size) \
|
|
46 fatal_unexec (_error_message, _error_arg);
|
|
47
|
|
48 #define WRITE(_fd, _buffer, _size, _error_message, _error_arg) \
|
|
49 if (write (_fd, _buffer, _size) != _size) \
|
|
50 fatal_unexec (_error_message, _error_arg);
|
|
51
|
|
52 #define SEEK(_fd, _position, _error_message, _error_arg) \
|
|
53 errno = EEOF; \
|
|
54 if (lseek (_fd, _position, L_SET) != _position) \
|
|
55 fatal_unexec (_error_message, _error_arg);
|
|
56
|
|
57 extern int errno;
|
|
58 extern char *strerror ();
|
|
59
|
|
60 void *sbrk();
|
|
61
|
|
62 #define EEOF -1
|
|
63
|
|
64 static struct scnhdr *text_section;
|
|
65 static struct scnhdr *init_section;
|
|
66 static struct scnhdr *finit_section;
|
|
67 static struct scnhdr *rdata_section;
|
|
68 static struct scnhdr *rconst_section;
|
|
69 static struct scnhdr *data_section;
|
|
70 static struct scnhdr *pdata_section;
|
|
71 static struct scnhdr *xdata_section;
|
|
72 static struct scnhdr *got_section;
|
|
73 static struct scnhdr *lit8_section;
|
|
74 static struct scnhdr *lit4_section;
|
|
75 static struct scnhdr *sdata_section;
|
|
76 static struct scnhdr *sbss_section;
|
|
77 static struct scnhdr *bss_section;
|
|
78
|
|
79 static unsigned long Brk;
|
|
80
|
|
81 struct headers {
|
|
82 struct filehdr fhdr;
|
|
83 struct aouthdr aout;
|
|
84 struct scnhdr section[_MIPS_NSCNS_MAX];
|
|
85 };
|
|
86
|
|
87
|
|
88
|
|
89 /* Define name of label for entry point for the dumped executable. */
|
|
90
|
|
91 #ifndef DEFAULT_ENTRY_ADDRESS
|
|
92 #define DEFAULT_ENTRY_ADDRESS __start
|
|
93 #endif
|
|
94
|
|
95 unexec (new_name, a_name, data_start, bss_start, entry_address)
|
|
96 char *new_name, *a_name;
|
|
97 unsigned long data_start, bss_start, entry_address;
|
|
98 {
|
|
99 int new, old;
|
|
100 char * oldptr;
|
|
101 struct headers ohdr, nhdr;
|
|
102 struct stat stat;
|
|
103 long pagesize, brk;
|
|
104 long newsyms, symrel;
|
|
105 int nread;
|
|
106 int i;
|
|
107 long vaddr, scnptr;
|
|
108 #define BUFSIZE 8192
|
|
109 char buffer[BUFSIZE];
|
|
110
|
|
111 if ((old = open (a_name, O_RDONLY)) < 0)
|
|
112 fatal_unexec ("opening %s", a_name);
|
|
113
|
|
114 new = creat (new_name, 0666);
|
|
115 if (new < 0) fatal_unexec ("creating %s", new_name);
|
|
116
|
|
117 if ((fstat (old, &stat) == -1))
|
|
118 fatal_unexec ("fstat %s", a_name);
|
|
119
|
|
120 oldptr = (char *)mmap (0, stat.st_size, PROT_READ, MAP_FILE|MAP_SHARED, old, 0);
|
|
121
|
|
122 if (oldptr == (char *)-1)
|
|
123 fatal_unexec ("mmap %s", a_name);
|
|
124
|
|
125 close (old);
|
|
126
|
|
127 /* This is a copy of the a.out header of the original executable */
|
|
128
|
|
129 ohdr = (*(struct headers *)oldptr);
|
|
130
|
|
131 /* This is where we build the new header from the in-memory copy */
|
|
132
|
|
133 nhdr = *((struct headers *)TEXT_START);
|
|
134
|
|
135 /* First do some consistency checks */
|
|
136
|
|
137 if (nhdr.fhdr.f_magic != ALPHAMAGIC
|
|
138 && nhdr.fhdr.f_magic != ALPHAUMAGIC)
|
|
139 {
|
|
140 fprintf (stderr, "unexec: input file magic number is %x, not %x or %x.\n",
|
|
141 nhdr.fhdr.f_magic, ALPHAMAGIC, ALPHAUMAGIC);
|
|
142 exit (1);
|
|
143 }
|
|
144
|
|
145 if (nhdr.fhdr.f_opthdr != sizeof (nhdr.aout))
|
|
146 {
|
173
|
147 fprintf (stderr, "unexec: input a.out header is %d bytes, not %ld.\n",
|
|
148 nhdr.fhdr.f_opthdr, (long) (sizeof (nhdr.aout)));
|
0
|
149 exit (1);
|
|
150 }
|
|
151 if (nhdr.aout.magic != ZMAGIC)
|
|
152 {
|
|
153 fprintf (stderr, "unexec: input file a.out magic number is %o, not %o.\n",
|
|
154 nhdr.aout.magic, ZMAGIC);
|
|
155 exit (1);
|
|
156 }
|
|
157
|
|
158
|
|
159 /* Now check the existence of certain header section and grab
|
|
160 their addresses. */
|
|
161
|
|
162 #define CHECK_SCNHDR(ptr, name, flags) \
|
|
163 ptr = NULL; \
|
|
164 for (i = 0; i < nhdr.fhdr.f_nscns && !ptr; i++) \
|
|
165 if (strcmp (nhdr.section[i].s_name, name) == 0) \
|
|
166 { \
|
|
167 if (nhdr.section[i].s_flags != flags) \
|
|
168 fprintf (stderr, "unexec: %x flags (%x expected) in %s section.\n", \
|
|
169 nhdr.section[i].s_flags, flags, name); \
|
|
170 ptr = nhdr.section + i; \
|
|
171 } \
|
|
172
|
|
173 CHECK_SCNHDR (text_section, _TEXT, STYP_TEXT);
|
|
174 CHECK_SCNHDR (init_section, _INIT, STYP_INIT);
|
|
175 #ifdef _FINI
|
|
176 CHECK_SCNHDR (finit_section, _FINI, STYP_FINI);
|
|
177 #endif /* _FINI */
|
|
178 CHECK_SCNHDR (rdata_section, _RDATA, STYP_RDATA);
|
|
179 #ifdef _RCONST
|
|
180 CHECK_SCNHDR (rconst_section, _RCONST, STYP_RCONST);
|
|
181 #endif
|
|
182 #ifdef _PDATA
|
|
183 CHECK_SCNHDR (pdata_section, _PDATA, STYP_PDATA);
|
|
184 #endif /* _PDATA */
|
|
185 #ifdef _GOT
|
|
186 CHECK_SCNHDR (got_section, _GOT, STYP_GOT);
|
|
187 #endif /* _GOT */
|
|
188 CHECK_SCNHDR (data_section, _DATA, STYP_DATA);
|
|
189 #ifdef _XDATA
|
|
190 CHECK_SCNHDR (xdata_section, _XDATA, STYP_XDATA);
|
|
191 #endif /* _XDATA */
|
|
192 #ifdef _LIT8
|
|
193 CHECK_SCNHDR (lit8_section, _LIT8, STYP_LIT8);
|
|
194 CHECK_SCNHDR (lit4_section, _LIT4, STYP_LIT4);
|
|
195 #endif /* _LIT8 */
|
|
196 CHECK_SCNHDR (sdata_section, _SDATA, STYP_SDATA);
|
|
197 CHECK_SCNHDR (sbss_section, _SBSS, STYP_SBSS);
|
|
198 CHECK_SCNHDR (bss_section, _BSS, STYP_BSS);
|
|
199
|
|
200
|
|
201 pagesize = getpagesize ();
|
|
202 brk = (((long) (sbrk (0))) + pagesize - 1) & (-pagesize);
|
|
203
|
|
204 /* Remember the current break */
|
|
205
|
|
206 Brk = brk;
|
|
207
|
|
208 nhdr.aout.dsize = brk - DATA_START;
|
|
209 nhdr.aout.bsize = 0;
|
|
210 if (entry_address == 0)
|
|
211 {
|
|
212 extern DEFAULT_ENTRY_ADDRESS ();
|
|
213 nhdr.aout.entry = (unsigned long)DEFAULT_ENTRY_ADDRESS;
|
|
214 }
|
|
215 else
|
|
216 nhdr.aout.entry = entry_address;
|
|
217
|
|
218 nhdr.aout.bss_start = nhdr.aout.data_start + nhdr.aout.dsize;
|
|
219
|
|
220 if (rdata_section != NULL)
|
|
221 {
|
|
222 rdata_section->s_size = data_start - DATA_START;
|
|
223
|
|
224 /* Adjust start and virtual addresses of rdata_section, too. */
|
|
225 rdata_section->s_vaddr = DATA_START;
|
|
226 rdata_section->s_paddr = DATA_START;
|
|
227 rdata_section->s_scnptr = text_section->s_scnptr + nhdr.aout.tsize;
|
|
228 }
|
|
229
|
|
230 data_section->s_vaddr = data_start;
|
|
231 data_section->s_paddr = data_start;
|
|
232 data_section->s_size = brk - data_start;
|
|
233
|
|
234 if (rdata_section != NULL)
|
|
235 {
|
|
236 data_section->s_scnptr = rdata_section->s_scnptr + rdata_section->s_size;
|
|
237 }
|
|
238
|
|
239 vaddr = data_section->s_vaddr + data_section->s_size;
|
|
240 scnptr = data_section->s_scnptr + data_section->s_size;
|
|
241 if (lit8_section != NULL)
|
|
242 {
|
|
243 lit8_section->s_vaddr = vaddr;
|
|
244 lit8_section->s_paddr = vaddr;
|
|
245 lit8_section->s_size = 0;
|
|
246 lit8_section->s_scnptr = scnptr;
|
|
247 }
|
|
248 if (lit4_section != NULL)
|
|
249 {
|
|
250 lit4_section->s_vaddr = vaddr;
|
|
251 lit4_section->s_paddr = vaddr;
|
|
252 lit4_section->s_size = 0;
|
|
253 lit4_section->s_scnptr = scnptr;
|
|
254 }
|
|
255 if (sdata_section != NULL)
|
|
256 {
|
|
257 sdata_section->s_vaddr = vaddr;
|
|
258 sdata_section->s_paddr = vaddr;
|
|
259 sdata_section->s_size = 0;
|
|
260 sdata_section->s_scnptr = scnptr;
|
|
261 }
|
|
262 #ifdef _XDATA
|
|
263 if (xdata_section != NULL)
|
|
264 {
|
|
265 xdata_section->s_vaddr = vaddr;
|
|
266 xdata_section->s_paddr = vaddr;
|
|
267 xdata_section->s_size = 0;
|
|
268 xdata_section->s_scnptr = scnptr;
|
|
269 }
|
|
270 #endif
|
|
271 #ifdef _GOT
|
|
272 if (got_section != NULL)
|
|
273 {
|
|
274 got_section->s_vaddr = vaddr;
|
|
275 got_section->s_paddr = vaddr;
|
|
276 got_section->s_size = 0;
|
|
277 got_section->s_scnptr = scnptr;
|
|
278 }
|
|
279 #endif /*_GOT */
|
|
280 if (sbss_section != NULL)
|
|
281 {
|
|
282 sbss_section->s_vaddr = vaddr;
|
|
283 sbss_section->s_paddr = vaddr;
|
|
284 sbss_section->s_size = 0;
|
|
285 sbss_section->s_scnptr = scnptr;
|
|
286 }
|
|
287 if (bss_section != NULL)
|
|
288 {
|
|
289 bss_section->s_vaddr = vaddr;
|
|
290 bss_section->s_paddr = vaddr;
|
|
291 bss_section->s_size = 0;
|
|
292 bss_section->s_scnptr = scnptr;
|
|
293 }
|
|
294
|
|
295 WRITE (new, (char *)TEXT_START, nhdr.aout.tsize,
|
|
296 "writing text section to %s", new_name);
|
|
297 WRITE (new, (char *)DATA_START, nhdr.aout.dsize,
|
|
298 "writing data section to %s", new_name);
|
|
299
|
|
300
|
|
301 /*
|
|
302 * Construct new symbol table header
|
|
303 */
|
|
304
|
282
|
305 memcpy (oldptr + nhdr.fhdr.f_symptr, buffer, cbHDRR);
|
0
|
306
|
|
307 #define symhdr ((pHDRR)buffer)
|
|
308 newsyms = nhdr.aout.tsize + nhdr.aout.dsize;
|
|
309 symrel = newsyms - nhdr.fhdr.f_symptr;
|
|
310 nhdr.fhdr.f_symptr = newsyms;
|
|
311 symhdr->cbLineOffset += symrel;
|
|
312 symhdr->cbDnOffset += symrel;
|
|
313 symhdr->cbPdOffset += symrel;
|
|
314 symhdr->cbSymOffset += symrel;
|
|
315 symhdr->cbOptOffset += symrel;
|
|
316 symhdr->cbAuxOffset += symrel;
|
|
317 symhdr->cbSsOffset += symrel;
|
|
318 symhdr->cbSsExtOffset += symrel;
|
|
319 symhdr->cbFdOffset += symrel;
|
|
320 symhdr->cbRfdOffset += symrel;
|
|
321 symhdr->cbExtOffset += symrel;
|
|
322
|
|
323 WRITE (new, buffer, cbHDRR, "writing symbol table header of %s", new_name);
|
|
324
|
|
325 /*
|
|
326 * Copy the symbol table and line numbers
|
|
327 */
|
|
328 WRITE (new, oldptr + ohdr.fhdr.f_symptr + cbHDRR,
|
|
329 stat.st_size - ohdr.fhdr.f_symptr - cbHDRR,
|
|
330 "writing symbol table of %s", new_name);
|
|
331
|
|
332 #if 0
|
|
333
|
|
334 /* Not needed for now */
|
|
335
|
|
336 update_dynamic_symbols (oldptr, new_name, new, newsyms,
|
|
337 ((pHDRR) (oldptr + ohdr.fhdr.f_symptr))->issExtMax,
|
|
338 ((pHDRR) (oldptr + ohdr.fhdr.f_symptr))->cbExtOffset,
|
|
339 ((pHDRR) (oldptr + ohdr.fhdr.f_symptr))->cbSsExtOffset);
|
|
340
|
|
341 #endif
|
|
342
|
|
343 #undef symhdr
|
|
344
|
|
345 SEEK (new, 0, "seeking to start of header in %s", new_name);
|
|
346 WRITE (new, &nhdr, sizeof (nhdr),
|
|
347 "writing header of %s", new_name);
|
|
348
|
|
349 close (old);
|
|
350 close (new);
|
|
351 mark_x (new_name);
|
173
|
352 return 0;
|
0
|
353 }
|
|
354
|
|
355
|
|
356 #if 0
|
|
357
|
|
358 /* Not needed for now */
|
|
359
|
|
360 /* The following function updates the values of some symbols
|
|
361 that are used by the dynamic loader:
|
|
362
|
|
363 _edata
|
|
364 _end
|
|
365
|
|
366 */
|
|
367
|
|
368
|
|
369 update_dynamic_symbols (old, new_name, new, newsyms, nsyms, symoff, stroff)
|
|
370 char *old; /* Pointer to old executable */
|
|
371 char *new_name; /* Name of new executable */
|
|
372 int new; /* File descriptor for new executable */
|
|
373 long newsyms; /* Offset of Symbol table in new executable */
|
|
374 int nsyms; /* Number of symbol table entries */
|
|
375 long symoff; /* Offset of External Symbols in old file */
|
|
376 long stroff; /* Offset of string table in old file */
|
|
377 {
|
|
378 long i;
|
|
379 int found = 0;
|
|
380 EXTR n_end, n_edata;
|
|
381
|
|
382 /* We go through the symbol table entries until we have found the two
|
|
383 symbols. */
|
|
384
|
|
385 /* cbEXTR is the size of an external symbol table entry */
|
|
386
|
|
387 for (i = 0; i < nsyms && found < 2; i += cbEXTR)
|
|
388 {
|
203
|
389 REGISTER pEXTR x = (pEXTR) (old + symoff + i);
|
0
|
390 char *s;
|
|
391
|
|
392 s = old + stroff + x->asym.iss; /* name of the symbol */
|
|
393
|
|
394 if (!strcmp(s,"_edata"))
|
|
395 {
|
|
396 found++;
|
282
|
397 memcpy (x, &n_edata, cbEXTR);
|
0
|
398 n_edata.asym.value = Brk;
|
|
399 SEEK (new, newsyms + cbHDRR + i,
|
|
400 "seeking to symbol _edata in %s", new_name);
|
|
401 WRITE (new, &n_edata, cbEXTR,
|
|
402 "writing symbol table entry for _edata into %s", new_name);
|
|
403 }
|
|
404 else if (!strcmp(s,"_end"))
|
|
405 {
|
|
406 found++;
|
282
|
407 memcpy (x, &n_end, cbEXTR);
|
0
|
408 n_end.asym.value = Brk;
|
|
409 SEEK (new, newsyms + cbHDRR + i,
|
|
410 "seeking to symbol _end in %s", new_name);
|
|
411 WRITE (new, &n_end, cbEXTR,
|
|
412 "writing symbol table entry for _end into %s", new_name);
|
|
413 }
|
|
414 }
|
|
415
|
|
416 }
|
|
417
|
|
418 #endif
|
|
419
|
|
420
|
|
421 /*
|
|
422 * mark_x
|
|
423 *
|
|
424 * After successfully building the new a.out, mark it executable
|
|
425 */
|
|
426
|
|
427 static void
|
173
|
428 mark_x (char *name)
|
0
|
429 {
|
|
430 struct stat sbuf;
|
|
431 int um = umask (777);
|
|
432 umask (um);
|
|
433 if (stat (name, &sbuf) < 0)
|
|
434 fatal_unexec ("getting protection on %s", name);
|
|
435 sbuf.st_mode |= 0111 & ~um;
|
|
436 if (chmod (name, sbuf.st_mode) < 0)
|
|
437 fatal_unexec ("setting protection on %s", name);
|
|
438 }
|
|
439
|
|
440 static void
|
173
|
441 fatal_unexec (char *s, char *arg)
|
0
|
442 {
|
|
443 if (errno == EEOF)
|
|
444 fputs ("unexec: unexpected end of file, ", stderr);
|
|
445 else
|
|
446 fprintf (stderr, "unexec: %s, ", strerror (errno));
|
|
447 fprintf (stderr, s, arg);
|
|
448 fputs (".\n", stderr);
|
|
449 exit (1);
|
|
450 }
|