Annotation of src/usr.bin/strip/strip.c, Revision 1.20
1.20 ! deraadt 1: /* $OpenBSD: strip.c,v 1.19 2003/06/03 02:56:17 millert Exp $ */
1.2 deraadt 2:
1.1 deraadt 3: /*
4: * Copyright (c) 1988 Regents of the University of California.
5: * All rights reserved.
6: *
7: * Redistribution and use in source and binary forms, with or without
8: * modification, are permitted provided that the following conditions
9: * are met:
10: * 1. Redistributions of source code must retain the above copyright
11: * notice, this list of conditions and the following disclaimer.
12: * 2. Redistributions in binary form must reproduce the above copyright
13: * notice, this list of conditions and the following disclaimer in the
14: * documentation and/or other materials provided with the distribution.
1.19 millert 15: * 3. Neither the name of the University nor the names of its contributors
1.1 deraadt 16: * may be used to endorse or promote products derived from this software
17: * without specific prior written permission.
18: *
19: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29: * SUCH DAMAGE.
30: */
31:
32: #ifndef lint
33: char copyright[] =
34: "@(#) Copyright (c) 1988 Regents of the University of California.\n\
35: All rights reserved.\n";
36: #endif /* not lint */
37:
38: #ifndef lint
39: /*static char sccsid[] = "from: @(#)strip.c 5.8 (Berkeley) 11/6/91";*/
1.20 ! deraadt 40: static char rcsid[] = "$OpenBSD: strip.c,v 1.19 2003/06/03 02:56:17 millert Exp $";
1.1 deraadt 41: #endif /* not lint */
42:
1.4 deraadt 43: #include <sys/param.h>
1.1 deraadt 44: #include <sys/types.h>
45: #include <sys/stat.h>
46: #include <sys/mman.h>
47: #include <fcntl.h>
48: #include <errno.h>
49: #include <a.out.h>
50: #include <unistd.h>
51: #include <stdio.h>
52: #include <stdlib.h>
53: #include <string.h>
1.7 mickey 54: #include <err.h>
1.11 espie 55: #include <ranlib.h>
56: #include "byte.c"
1.10 niklas 57:
58: #ifdef MID_MACHINE_OVERRIDE
59: #undef MID_MACHINE
60: #define MID_MACHINE MID_MACHINE_OVERRIDE
61: #endif
1.1 deraadt 62:
63: typedef struct exec EXEC;
64: typedef struct nlist NLIST;
65:
66: #define strx n_un.n_strx
67:
1.17 espie 68: int s_stab(const char *, int, EXEC *, struct stat *, off_t *);
69: int s_sym(const char *, int, EXEC *, struct stat *, off_t *);
1.16 millert 70: void usage(void);
1.1 deraadt 71:
72: int xflag = 0;
73:
1.9 deraadt 74: int
1.20 ! deraadt 75: main(int argc, char *argv[])
1.1 deraadt 76: {
1.15 mpech 77: int fd;
1.1 deraadt 78: EXEC *ep;
79: struct stat sb;
1.17 espie 80: int (*sfcn)(const char *, int, EXEC *, struct stat *, off_t *);
1.1 deraadt 81: int ch, errors;
82: char *fn;
1.17 espie 83: off_t newsize;
1.1 deraadt 84:
85: sfcn = s_sym;
1.6 millert 86: while ((ch = getopt(argc, argv, "dx")) != -1)
1.1 deraadt 87: switch(ch) {
88: case 'x':
89: xflag = 1;
90: /*FALLTHROUGH*/
91: case 'd':
92: sfcn = s_stab;
93: break;
94: case '?':
95: default:
96: usage();
97: }
98: argc -= optind;
99: argv += optind;
100:
101: errors = 0;
1.8 mickey 102: #define ERROR(x) errors |= 1; warnx("%s: %s", fn, strerror(x)); continue;
1.9 deraadt 103: while ((fn = *argv++)) {
1.1 deraadt 104: if ((fd = open(fn, O_RDWR)) < 0) {
105: ERROR(errno);
106: }
107: if (fstat(fd, &sb)) {
108: (void)close(fd);
109: ERROR(errno);
110: }
111: if (sb.st_size < sizeof(EXEC)) {
112: (void)close(fd);
113: ERROR(EFTYPE);
114: }
115: if ((ep = (EXEC *)mmap(NULL, sb.st_size, PROT_READ|PROT_WRITE,
1.13 art 116: MAP_SHARED, fd, (off_t)0)) == MAP_FAILED) {
1.1 deraadt 117: (void)close(fd);
118: ERROR(errno);
119: }
1.11 espie 120: if (BAD_OBJECT(*ep)) {
1.1 deraadt 121: munmap((caddr_t)ep, sb.st_size);
122: (void)close(fd);
123: ERROR(EFTYPE);
124: }
1.11 espie 125: /* since we're dealing with an mmap there, we have to convert once
126: for dealing with data in memory, and a second time for out
127: */
128: fix_header_order(ep);
1.17 espie 129: newsize = 0;
130: errors |= sfcn(fn, fd, ep, &sb, &newsize);
1.11 espie 131: fix_header_order(ep);
1.1 deraadt 132: munmap((caddr_t)ep, sb.st_size);
1.17 espie 133: if (newsize && ftruncate(fd, newsize)) {
134: warn("%s", fn);
135: errors = 1;
136: }
1.1 deraadt 137: if (close(fd)) {
138: ERROR(errno);
139: }
140: }
141: #undef ERROR
142: exit(errors);
143: }
144:
145: int
1.20 ! deraadt 146: s_sym(const char *fn, int fd, EXEC *ep, struct stat *sp, off_t *sz)
1.1 deraadt 147: {
1.15 mpech 148: char *neweof;
1.14 pvalchev 149: #if 0
1.15 mpech 150: char *mineof;
1.14 pvalchev 151: #endif
1.1 deraadt 152: int zmagic;
153:
154: zmagic = ep->a_data &&
155: (N_GETMAGIC(*ep) == ZMAGIC || N_GETMAGIC(*ep) == QMAGIC);
156:
157: /*
158: * If no symbols or data/text relocation info and
159: * the file data segment size is already minimized, quit.
160: */
161: if (!ep->a_syms && !ep->a_trsize && !ep->a_drsize) {
162: #if 0
163: if (!zmagic)
164: return 0;
165: if (sp->st_size < N_TRELOFF(*ep))
166: #endif
167: return 0;
168: }
169:
170: /*
171: * New file size is the header plus text and data segments; OMAGIC
172: * and NMAGIC formats have the text/data immediately following the
173: * header. ZMAGIC format wastes the rest of of header page.
174: */
175: neweof = (char *)ep + N_TRELOFF(*ep);
176:
177: #if 0
178: /*
179: * Unfortunately, this can't work correctly without changing the way
180: * the loader works. We could cap it at one page, or even fiddle with
181: * a_data and a_bss, but this only works for CLBYTES == NBPG. If we
182: * are on a system where, e.g., CLBYTES is 8k and NBPG is 4k, and we
183: * happen to remove 4.5k, we will lose. And we really don't want to
184: * fiddle with pages, because that breaks binary compatibility. Lose.
185: */
186:
187: if (zmagic) {
188: /*
189: * Get rid of unneeded zeroes at the end of the data segment
190: * to reduce the file size even more.
191: */
192: mineof = (char *)ep + N_DATOFF(*ep);
193: while (neweof > mineof && neweof[-1] == '\0')
194: neweof--;
195: }
196: #endif
197:
198: /* Set symbol size and relocation info values to 0. */
199: ep->a_syms = ep->a_trsize = ep->a_drsize = 0;
200:
201: /* Truncate the file. */
1.17 espie 202: *sz = neweof - (char *)ep;
1.1 deraadt 203:
204: return 0;
205: }
206:
207: int
1.20 ! deraadt 208: s_stab(const char *fn, int fd, EXEC *ep, struct stat *sp, off_t *sz)
1.1 deraadt 209: {
1.15 mpech 210: int cnt, len;
1.18 espie 211: char *nstr, *nstrbase=0, *used=0, *p, *strbase;
1.15 mpech 212: NLIST *sym, *nsym;
1.11 espie 213: u_long allocsize;
214: int mid;
1.1 deraadt 215: NLIST *symbase;
1.18 espie 216: unsigned int *mapping=0;
217: int error=1;
218: unsigned int nsyms;
219: struct relocation_info *reloc_base;
220: unsigned int i, j;
1.1 deraadt 221:
222: /* Quit if no symbols. */
223: if (ep->a_syms == 0)
224: return 0;
225:
226: if (N_SYMOFF(*ep) >= sp->st_size) {
1.7 mickey 227: warnx("%s: bad symbol table", fn);
1.1 deraadt 228: return 1;
229: }
230:
1.11 espie 231: mid = N_GETMID(*ep);
232:
1.1 deraadt 233: /*
234: * Initialize old and new symbol pointers. They both point to the
235: * beginning of the symbol table in memory, since we're deleting
236: * entries.
237: */
238: sym = nsym = symbase = (NLIST *)((char *)ep + N_SYMOFF(*ep));
239:
240: /*
241: * Allocate space for the new string table, initialize old and
242: * new string pointers. Handle the extra long at the beginning
243: * of the string table.
244: */
245: strbase = (char *)ep + N_STROFF(*ep);
1.11 espie 246: allocsize = fix_long_order(*(u_long *)strbase, mid);
247: if ((nstrbase = malloc((u_int) allocsize)) == NULL) {
1.7 mickey 248: warnx("%s", strerror(ENOMEM));
1.18 espie 249: goto end;
1.1 deraadt 250: }
251: nstr = nstrbase + sizeof(u_long);
252:
1.18 espie 253: /* okay, so we also need to keep symbol numbers for relocations. */
254: nsyms = ep->a_syms/ sizeof(NLIST);
255: used = calloc(nsyms, 1);
256: if (!used) {
257: warnx("%s", strerror(ENOMEM));
258: goto end;
259: }
260: mapping = malloc(nsyms * sizeof(unsigned int));
261: if (!mapping) {
262: warnx("%s", strerror(ENOMEM));
263: goto end;
264: }
265:
266: if ((ep->a_trsize || ep->a_drsize) && byte_sex(mid) != BYTE_ORDER) {
267: warnx("%s: cross-stripping not supported", fn);
268: goto end;
269: }
270:
271: /* first check the relocations for used symbols, and mark them */
272: /* text */
273: reloc_base = (struct relocation_info *) ((char *)ep + N_TRELOFF(*ep));
274: if (N_TRELOFF(*ep) + ep->a_trsize > sp->st_size) {
275: warnx("%s: bad text relocation", fn);
276: goto end;
277: }
278: for (i = 0; i < ep->a_trsize / sizeof(struct relocation_info); i++) {
279: if (!reloc_base[i].r_extern)
280: continue;
281: if (reloc_base[i].r_symbolnum > nsyms) {
282: warnx("%s: bad symbol number in text relocation", fn);
283: goto end;
284: }
285: used[reloc_base[i].r_symbolnum] = 1;
286: }
287: /* data */
288: reloc_base = (struct relocation_info *) ((char *)ep + N_DRELOFF(*ep));
289: if (N_DRELOFF(*ep) + ep->a_drsize > sp->st_size) {
290: warnx("%s: bad data relocation", fn);
291: goto end;
292: }
293: for (i = 0; i < ep->a_drsize / sizeof(struct relocation_info); i++) {
294: if (!reloc_base[i].r_extern)
295: continue;
296: if (reloc_base[i].r_symbolnum > nsyms) {
297: warnx("%s: bad symbol number in data relocation", fn);
298: goto end;
299: }
300: used[reloc_base[i].r_symbolnum] = 1;
301: }
302:
1.1 deraadt 303: /*
304: * Read through the symbol table. For each non-debugging symbol,
305: * copy it and save its string in the new string table. Keep
306: * track of the number of symbols.
307: */
1.18 espie 308: for (cnt = nsyms, i = 0, j = 0; cnt--; ++sym, ++i) {
1.11 espie 309: fix_nlist_order(sym, mid);
1.1 deraadt 310: if (!(sym->n_type & N_STAB) && sym->strx) {
311: *nsym = *sym;
312: nsym->strx = nstr - nstrbase;
313: p = strbase + sym->strx;
1.18 espie 314: if (xflag && !used[i] &&
1.1 deraadt 315: (!(sym->n_type & N_EXT) ||
316: (sym->n_type & ~N_EXT) == N_FN ||
317: strcmp(p, "gcc_compiled.") == 0 ||
318: strcmp(p, "gcc2_compiled.") == 0 ||
319: strncmp(p, "___gnu_compiled_", 16) == 0)) {
320: continue;
321: }
322: len = strlen(p) + 1;
1.18 espie 323: mapping[i] = j++;
1.17 espie 324: if (N_STROFF(*ep) + sym->strx + len > sp->st_size) {
325: warnx("%s: bad symbol table", fn);
1.18 espie 326: goto end;
1.17 espie 327: }
1.1 deraadt 328: bcopy(p, nstr, len);
329: nstr += len;
1.11 espie 330: fix_nlist_order(nsym++, mid);
1.1 deraadt 331: }
1.11 espie 332: }
1.1 deraadt 333:
1.18 espie 334: /* renumber symbol relocations */
335: /* text */
336: reloc_base = (struct relocation_info *) ((char *)ep + N_TRELOFF(*ep));
337: for (i = 0; i < ep->a_trsize / sizeof(struct relocation_info); i++) {
338: if (!reloc_base[i].r_extern)
339: continue;
340: reloc_base[i].r_symbolnum = mapping[reloc_base[i].r_symbolnum];
341: }
342: /* data */
343: reloc_base = (struct relocation_info *) ((char *)ep + N_DRELOFF(*ep));
344: for (i = 0; i < ep->a_drsize / sizeof(struct relocation_info); i++) {
345: if (!reloc_base[i].r_extern)
346: continue;
347: reloc_base[i].r_symbolnum = mapping[reloc_base[i].r_symbolnum];
348: }
349:
1.1 deraadt 350: /* Fill in new symbol table size. */
351: ep->a_syms = (nsym - symbase) * sizeof(NLIST);
352:
353: /* Fill in the new size of the string table. */
1.11 espie 354: len = nstr - nstrbase;
355: *(u_long *)nstrbase = fix_long_order(len, mid);
1.1 deraadt 356:
357: /*
358: * Copy the new string table into place. Nsym should be pointing
359: * at the address past the last symbol entry.
360: */
361: bcopy(nstrbase, (void *)nsym, len);
1.18 espie 362: error = 0;
363: end:
1.1 deraadt 364: free(nstrbase);
1.18 espie 365: free(used);
366: free(mapping);
1.1 deraadt 367:
368: /* Truncate to the current length. */
1.17 espie 369: *sz = (char *)nsym + len - (char *)ep;
1.1 deraadt 370:
1.18 espie 371: return error;
1.1 deraadt 372: }
373:
374: void
1.20 ! deraadt 375: usage(void)
1.1 deraadt 376: {
377: (void)fprintf(stderr, "usage: strip [-dx] file ...\n");
378: exit(1);
379: }
380:
![[BACK]](/icons/back.gif){kind=icon}
Return to strip.c CVS log ![[TXT]](/icons/text.gif){kind=icon}
![[DIR]](/icons/dir.gif){kind=icon}
Up to [local] / src / usr.bin / strip