1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22 /*
23 * Copyright (c) 1990, 2010, Oracle and/or its affiliates. All rights reserved.
24 */
25
26 /*
27 * Copyright (c) 1988 AT&T
28 * All Rights Reserved
29 */
30
31 #include <ar.h>
32 #include <stdlib.h>
33 #include <memory.h>
34 #include <errno.h>
35 #include <libelf.h>
36 #include "decl.h"
37 #include "msg.h"
38 #include "member.h"
39
40 #define MANGLE '\177'
41
42
43 /*
44 * Archive processing
45 * When processing an archive member, two things can happen
46 * that are a little tricky.
47 *
48 * Sliding
49 * Sliding support is left in for backward compatibility and for
50 * support of Archives produced on other systems. The bundled
51 * ar(1) produces archives with all members on a 4 byte boundry,
52 * so current archives should need no sliding.
53 *
54 * Archive members that are only 2-byte aligned within the file will
55 * be slid. To reuse the file's memory image, the library slides an
56 * archive member into its header to align the bytes. This means
57 * the header must be disposable.
58 *
59 * Header reuse
60 * Because the library can trample the header, it must be preserved to
61 * avoid restrictions on archive member reuse. That is, if the member
62 * header changes, the library may see garbage the next time it looks
63 * at the header. After extracting the original header, the library
64 * appends it to the parents `ed_memlist' list, thus future lookups first
65 * check this list to determine if a member has previously been processed
66 * and whether sliding occured.
67 */
68
69
70 /*
71 * Size check
72 * If the header is too small, the following generates a negative
73 * subscript for x.x and fails to compile.
74 *
75 * The check is based on sizeof (Elf64) because that's always going
76 * to be at least as big as Elf32.
77 */
78
79 struct x
80 {
81 char x[sizeof (struct ar_hdr) - 3 * sizeof (Elf64) - 1];
82 };
83
84
85
86 static const char fmag[] = ARFMAG;
87
88
89 /*
90 * Convert a string starting at 'p' and ending at 'end' into
91 * an integer. Base is the base of the number being converted
92 * (either 8 or 10).
93 *
94 * Returns the converted integer of the string being scaned.
95 */
96 unsigned long
_elf_number(char * p,char * end,int base)97 _elf_number(char *p, char *end, int base)
98 {
99 register unsigned c;
100 register unsigned long n = 0;
101
102 while (p < end) {
103 if ((c = *p - '0') >= base) {
104 while (*p++ == ' ')
105 if (p >= end)
106 return (n);
107 return (0);
108 }
109 n *= base;
110 n += c;
111 ++p;
112 }
113 return (n);
114 }
115
116
117 /*
118 * Convert ar_hdr to Member
119 * Converts ascii file representation to the binary memory values.
120 */
121 Member *
_elf_armem(Elf * elf,char * file,size_t fsz)122 _elf_armem(Elf *elf, char *file, size_t fsz)
123 {
124 register struct ar_hdr *f = (struct ar_hdr *)file;
125 register Member *m;
126 register Memlist *l, * ol;
127 register Memident *i;
128
129 if (fsz < sizeof (struct ar_hdr)) {
130 _elf_seterr(EFMT_ARHDRSZ, 0);
131 return (0);
132 }
133
134 /*
135 * Determine in this member has already been processed
136 */
137 for (l = elf->ed_memlist, ol = l; l; ol = l, l = l->m_next)
138 for (i = (Memident *)(l + 1); i < l->m_free; i++)
139 if (i->m_offset == file)
140 return (i->m_member);
141
142 if (f->ar_fmag[0] != fmag[0] || f->ar_fmag[1] != fmag[1]) {
143 _elf_seterr(EFMT_ARFMAG, 0);
144 return (0);
145 }
146
147 /*
148 * Allocate a new member structure and assign it to the next free
149 * free memlist ident.
150 */
151 if ((m = (Member *)malloc(sizeof (Member))) == 0) {
152 _elf_seterr(EMEM_ARMEM, errno);
153 return (0);
154 }
155 if ((elf->ed_memlist == 0) || (ol->m_free == ol->m_end)) {
156 if ((l = (Memlist *)malloc(sizeof (Memlist) +
157 (sizeof (Memident) * MEMIDENTNO))) == 0) {
158 _elf_seterr(EMEM_ARMEM, errno);
159 return (0);
160 }
161 l->m_next = 0;
162 l->m_free = (Memident *)(l + 1);
163 l->m_end = (Memident *)((uintptr_t)l->m_free +
164 (sizeof (Memident) * MEMIDENTNO));
165
166 if (elf->ed_memlist == 0)
167 elf->ed_memlist = l;
168 else
169 ol->m_next = l;
170 ol = l;
171 }
172 ol->m_free->m_offset = file;
173 ol->m_free->m_member = m;
174 ol->m_free++;
175
176 m->m_err = 0;
177 (void) memcpy(m->m_name, f->ar_name, ARSZ(ar_name));
178 m->m_name[ARSZ(ar_name)] = '\0';
179 m->m_hdr.ar_name = m->m_name;
180 (void) memcpy(m->m_raw, f->ar_name, ARSZ(ar_name));
181 m->m_raw[ARSZ(ar_name)] = '\0';
182 m->m_hdr.ar_rawname = m->m_raw;
183 m->m_slide = 0;
184
185 /*
186 * Classify file name.
187 * If a name error occurs, delay until getarhdr().
188 */
189
190 if (f->ar_name[0] != '/') { /* regular name */
191 register char *p;
192
193 p = &m->m_name[sizeof (m->m_name)];
194 while (*--p != '/')
195 if (p <= m->m_name)
196 break;
197 *p = '\0';
198 } else if (f->ar_name[1] >= '0' && f->ar_name[1] <= '9') { /* strtab */
199 register unsigned long j;
200
201 j = _elf_number(&f->ar_name[1],
202 &f->ar_name[ARSZ(ar_name)], 10);
203 if (j < elf->ed_arstrsz)
204 m->m_hdr.ar_name = elf->ed_arstr + j;
205 else {
206 m->m_hdr.ar_name = 0;
207 /*LINTED*/ /* MSG_INTL(EFMT_ARSTRNM) */
208 m->m_err = (int)EFMT_ARSTRNM;
209 }
210 } else if (f->ar_name[1] == ' ') /* "/" */
211 m->m_name[1] = '\0';
212 else if (f->ar_name[1] == '/' && f->ar_name[2] == ' ') /* "//" */
213 m->m_name[2] = '\0';
214 else if (f->ar_name[1] == 'S' && f->ar_name[2] == 'Y' &&
215 f->ar_name[3] == 'M' && f->ar_name[4] == '6' &&
216 f->ar_name[5] == '4' && f->ar_name[6] == '/' &&
217 f->ar_name[7] == ' ') /* "/SYM64/" */
218 m->m_name[7] = '\0';
219 else { /* "/?" */
220 m->m_hdr.ar_name = 0;
221 /*LINTED*/ /* MSG_INTL(EFMT_ARUNKNM) */
222 m->m_err = (int)EFMT_ARUNKNM;
223 }
224
225 m->m_hdr.ar_date = (time_t)_elf_number(f->ar_date,
226 &f->ar_date[ARSZ(ar_date)], 10);
227 /* LINTED */
228 m->m_hdr.ar_uid = (uid_t)_elf_number(f->ar_uid,
229 &f->ar_uid[ARSZ(ar_uid)], 10);
230 /* LINTED */
231 m->m_hdr.ar_gid = (gid_t)_elf_number(f->ar_gid,
232 &f->ar_gid[ARSZ(ar_gid)], 10);
233 /* LINTED */
234 m->m_hdr.ar_mode = (mode_t)_elf_number(f->ar_mode,
235 &f->ar_mode[ARSZ(ar_mode)], 8);
236 m->m_hdr.ar_size = (off_t)_elf_number(f->ar_size,
237 &f->ar_size[ARSZ(ar_size)], 10);
238
239 return (m);
240 }
241
242
243 /*
244 * Initial archive processing
245 * An archive may have two special members.
246 *
247 * A symbol table, named / or /SYM64/, must be first if it is present.
248 * Both forms use the same layout differing in the width of the
249 * integer type used (32 or 64-bit respectively).
250 *
251 * A long name string table, named //, must precede all "normal"
252 * members. This string table is used to hold the names of archive
253 * members with names that are longer than 15 characters. It should not
254 * be confused with the string table found at the end of the symbol
255 * table, which is used to hold symbol names.
256 *
257 * This code "peeks" at headers but doesn't change them.
258 * Later processing wants original headers.
259 *
260 * String table is converted, changing '/' name terminators
261 * to nulls. The last byte in the string table, which should
262 * be '\n', is set to nil, guaranteeing null termination. That
263 * byte should be '\n', but this code doesn't check.
264 *
265 * The symbol table conversion is delayed until needed.
266 */
267 void
_elf_arinit(Elf * elf)268 _elf_arinit(Elf * elf)
269 {
270 char *base = elf->ed_ident;
271 register char *end = base + elf->ed_fsz;
272 register struct ar_hdr *a;
273 register char *hdr = base + SARMAG;
274 register char *mem;
275 int j;
276 size_t sz = SARMAG;
277
278 elf->ed_status = ES_COOKED;
279 elf->ed_nextoff = SARMAG;
280 for (j = 0; j < 2; ++j) { /* 2 special members */
281 unsigned long n;
282
283 if (((end - hdr) < sizeof (struct ar_hdr)) ||
284 (_elf_vm(elf, (size_t)(SARMAG),
285 sizeof (struct ar_hdr)) != OK_YES))
286 return;
287
288 a = (struct ar_hdr *)hdr;
289 mem = (char *)a + sizeof (struct ar_hdr);
290 n = _elf_number(a->ar_size, &a->ar_size[ARSZ(ar_size)], 10);
291 if ((end - mem < n) || (a->ar_name[0] != '/') ||
292 ((sz = n) != n)) {
293 return;
294 }
295
296 hdr = mem + sz;
297 if (a->ar_name[1] == ' ') { /* 32-bit symbol table */
298 elf->ed_arsym = mem;
299 elf->ed_arsymsz = sz;
300 elf->ed_arsymoff = (char *)a - base;
301 } else if (a->ar_name[1] == '/' && a->ar_name[2] == ' ') {
302 /* Long name string table */
303 int k;
304
305 if (_elf_vm(elf, (size_t)(mem - elf->ed_ident),
306 sz) != OK_YES)
307 return;
308 if (elf->ed_vm == 0) {
309 char *nmem;
310 if ((nmem = malloc(sz)) == 0) {
311 _elf_seterr(EMEM_ARSTR, errno);
312 return;
313 }
314 (void) memcpy(nmem, mem, sz);
315 elf->ed_myflags |= EDF_ASTRALLOC;
316 mem = nmem;
317 }
318
319 elf->ed_arstr = mem;
320 elf->ed_arstrsz = sz;
321 elf->ed_arstroff = (char *)a - base;
322 for (k = 0; k < sz; k++) {
323 if (*mem == '/')
324 *mem = '\0';
325 ++mem;
326 }
327 *(mem - 1) = '\0';
328 } else if (a->ar_name[1] == 'S' && a->ar_name[2] == 'Y' &&
329 a->ar_name[3] == 'M' && a->ar_name[4] == '6' &&
330 a->ar_name[5] == '4' && a->ar_name[6] == '/' &&
331 a->ar_name[7] == ' ') {
332 /* 64-bit symbol table */
333 elf->ed_arsym = mem;
334 elf->ed_arsymsz = sz;
335 elf->ed_arsymoff = (char *)a - base;
336 elf->ed_myflags |= EDF_ARSYM64;
337 } else {
338 return;
339 }
340 hdr += sz & 1;
341 }
342 }
343