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) 2004, 2010, Oracle and/or its affiliates. All rights reserved.
24 */
25
26 #if defined(_KERNEL)
27 #include <sys/types.h>
28 #include "reloc.h"
29 #else
30 #define ELF_TARGET_AMD64
31 #if defined(DO_RELOC_LIBLD)
32 #undef DO_RELOC_LIBLD
33 #define DO_RELOC_LIBLD_X86
34 #endif
35 #include <stdio.h>
36 #include "sgs.h"
37 #include "machdep.h"
38 #include "libld.h"
39 #include "reloc.h"
40 #include "conv.h"
41 #include "msg.h"
42 #endif
43
44 /*
45 * We need to build this code differently when it is used for
46 * cross linking:
47 * - Data alignment requirements can differ from those
48 * of the running system, so we can't access data
49 * in units larger than a byte
50 * - We have to include code to do byte swapping when the
51 * target and linker host use different byte ordering,
52 * but such code is a waste when running natively.
53 */
54 #if !defined(DO_RELOC_LIBLD) || defined(__i386) || defined(__amd64)
55 #define DORELOC_NATIVE
56 #endif
57
58 /*
59 * This table represents the current relocations that do_reloc() is able to
60 * process. The relocations below that are marked SPECIAL are relocations that
61 * take special processing and shouldn't actually ever be passed to do_reloc().
62 */
63 const Rel_entry reloc_table[R_AMD64_NUM] = {
64 /* R_AMD64_NONE */ {0, FLG_RE_NOTREL, 0, 0, 0},
65 /* R_AMD64_64 */ {0, FLG_RE_NOTREL, 8, 0, 0},
66 /* R_AMD64_PC32 */ {0, FLG_RE_PCREL, 4, 0, 0},
67 /* R_AMD64_GOT32 */ {0, FLG_RE_NOTSUP, 0, 0, 0},
68 /* R_AMD64_PLT32 */ {0, FLG_RE_PCREL | FLG_RE_PLTREL |
69 FLG_RE_VERIFY | FLG_RE_SIGN, 4, 0, 0},
70 /* R_AMD64_COPY */ {0, FLG_RE_NOTSUP, 0, 0, 0}, /* SPECIAL */
71 /* R_AMD64_GLOB_DAT */ {0, FLG_RE_NOTREL, 8, 0, 0},
72 /* R_AMD64_JUMP_SLOT */ {0, FLG_RE_NOTSUP, 0, 0, 0}, /* SPECIAL */
73 /* R_AMD64_RELATIVE */ {0, FLG_RE_NOTREL, 8, 0, 0},
74 /* R_AMD64_GOTPCREL */ {0, FLG_RE_GOTPC | FLG_RE_GOTADD, 4, 0, 0},
75 /* R_AMD64_32 */ {0, FLG_RE_NOTREL, 4, 0, 0},
76 /* R_AMD64_32S */ {0, FLG_RE_NOTREL, 4, 0, 0},
77 /* R_AMD64_16 */ {0, FLG_RE_NOTREL, 2, 0, 0},
78 /* R_AMD64_PC16 */ {0, FLG_RE_PCREL, 2, 0, 0},
79 /* R_AMD64_8 */ {0, FLG_RE_NOTREL, 1, 0, 0},
80 /* R_AMD64_PC8 */ {0, FLG_RE_PCREL, 1, 0, 0},
81 /* R_AMD64_DTPMOD64 */ {0, FLG_RE_NOTREL, 8, 0, 0},
82 /* R_AMD64_DTPOFF64 */ {0, FLG_RE_NOTREL, 8, 0, 0},
83 /* R_AMD64_TPOFF64 */ {0, FLG_RE_NOTREL, 8, 0, 0},
84 /* R_AMD64_TLSGD */ {0, FLG_RE_GOTPC | FLG_RE_GOTADD | FLG_RE_TLSGD,
85 4, 0, 0},
86 /* R_AMD64_TLSLD */ {0, FLG_RE_GOTPC | FLG_RE_GOTADD | FLG_RE_TLSLD,
87 4, 0, 0},
88 /* R_AMD64_DTPOFF32 */ {0, FLG_RE_TLSLD, 4},
89 /* R_AMD64_GOTTPOFF */ {0, FLG_RE_GOTPC | FLG_RE_GOTADD | FLG_RE_TLSIE,
90 4, 0, 0},
91 /* R_AMD64_TPOFF32 */ {0, FLG_RE_TLSLE, 4, 0, 0},
92 /* R_AMD64_PC64 */ {0, FLG_RE_PCREL, 8, 0, 0},
93 /* R_AMD64_GOTOFF64 */ {0, FLG_RE_GOTREL, 8, 0, 0},
94 /* R_AMD64_GOTPC32 */ {0, FLG_RE_PCREL | FLG_RE_GOTPC | FLG_RE_LOCLBND,
95 4, 0, 0},
96 /* R_AMD64_GOT64 */ {0, FLG_RE_NOTSUP, 0, 0, 0},
97 /* R_AMD64_GOTPCREL64 */ {FLG_RE_NOTSUP, 0, 0, 0},
98 /* R_AMD64_GOTPC6 */ {0, FLG_RE_NOTSUP, 0, 0, 0},
99 /* R_AMD64_GOTPLT64 */ {0, FLG_RE_NOTSUP, 0, 0, 0},
100 /* R_AMD64_PLTOFF64 */ {0, FLG_RE_NOTSUP, 0, 0, 0},
101 /* R_AMD64_SIZE32 */ {0, FLG_RE_SIZE, 4, 0, 0},
102 /* R_AMD64_SIZE64 */ {0, FLG_RE_SIZE, 8, 0, 0}
103 };
104 #if (R_AMD64_NUM != (R_AMD64_SIZE64 + 1))
105 #error "R_AMD64_NUM has grown"
106 #endif
107
108 /*
109 * Write a single relocated value to its reference location.
110 * We assume we wish to add the relocation amount, value, to the
111 * value of the address already present at the offset.
112 *
113 * NAME VALUE FIELD CALCULATION
114 *
115 * R_AMD64_NONE 0 none none
116 * R_AMD64_64 1 word64 S + A
117 * R_AMD64_PC32 2 word64 S + A
118 * R_AMD64_GOT32 3 word32 G + A
119 * R_AMD64_PLT32 4 word32 L + A - P
120 * R_AMD64_COPY 5 none none
121 * R_AMD64_GLOB_DAT 6 word64 S
122 * R_AMD64_JUMP_SLOT 7 word64 S
123 * R_AMD64_RELATIVE 8 word64 B + A
124 * R_AMD64_GOTPCREL 9 word32 G + GOT + A - P
125 * R_AMD64_32 10 word32 S + A
126 * R_AMD64_32S 11 word32 S + A
127 * R_AMD64_16 12 word16 S + A
128 * R_AMD64_PC16 13 word16 S + A - P
129 * R_AMD64_8 14 word8 S + A
130 * R_AMD64_PC8 15 word8 S + A - P
131 * R_AMD64_DTPMOD64 16 word64
132 * R_AMD64_DTPOFF64 17 word64
133 * R_AMD64_TPOFF64 18 word64
134 * R_AMD64_TLSGD 19 word32
135 * R_AMD64_TLSLD 20 word32
136 * R_AMD64_DTPOFF32 21 word32
137 * R_AMD64_GOTTPOFF 22 word32
138 * R_AMD64_TPOFF32 23 word32
139 * R_AMD64_PC64 24 word32 S + A - P
140 * R_AMD64_GOTOFF64 25 word32 S + A - GOT
141 * R_AMD64_GOTPC32 26 word32 GOT + A - P
142 * R_AMD64_GOT64 27 reserved for future expansion
143 * R_AMD64_GOTPCREL64 28 reserved for future expansion
144 * R_AMD64_GOTPC64 29 reserved for future expansion
145 * R_AMD64_GOTPLT64 30 reserved for future expansion
146 * R_AMD64_PLTOFF64 31 reserved for future expansion
147 * R_AMD64_SIZE32 32 word32 Z + A
148 * R_AMD64_SIZE64 33 word64 Z + A
149 *
150 * Relocation calculations:
151 * A Represents the addend used to compute the value of the
152 * relocatable field.
153 *
154 * B Represents the base address at which a shared objects has
155 * been loaded into memory during executaion. Generally, a
156 * shared objects is built with a 0 base virtual address,
157 * but the execution address will be different.
158 *
159 * G Represents the offset into the global offset table
160 * at which the relocation entry's symbol will reside
161 * during execution.
162 *
163 * GOT Rrepresents the address of the global offset table.
164 *
165 * L Represents the place (section offset or address) of
166 * the Procedure Linkage Table entry for a symbol.
167 *
168 * P Represents the place (section offset or address) of the
169 * storage unit being relocated (computed using r_offset).
170 *
171 * S Represents the value of the symbol whose index resides
172 * in the relocation entry.
173 *
174 * Z the size of the symbol whose index resides in the relocation
175 * entry
176 */
177
178
179 /*
180 * Bits that must be cleared or identical for a value to act as if extended in
181 * the given way.
182 */
183 #define ZEROEXBITS 0xffffffff00000000ULL
184 #define SIGNEXBITS 0xffffffff80000000ULL
185
186 #if defined(_KERNEL)
187 #define lml 0 /* Needed by arglist of REL_ERR_* macros */
188 int
do_reloc_krtld(uchar_t rtype,uchar_t * off,Xword * value,const char * sym,const char * file)189 do_reloc_krtld(uchar_t rtype, uchar_t *off, Xword *value, const char *sym,
190 const char *file)
191 #elif defined(DO_RELOC_LIBLD)
192 /*ARGSUSED5*/
193 int
194 do_reloc_ld(Rel_desc *rdesc, uchar_t *off, Xword *value,
195 rel_desc_sname_func_t rel_desc_sname_func,
196 const char *file, int bswap, void *lml)
197 #else
198 int
199 do_reloc_rtld(uchar_t rtype, uchar_t *off, Xword *value, const char *sym,
200 const char *file, void *lml)
201 #endif
202 {
203 #ifdef DO_RELOC_LIBLD
204 #define sym (* rel_desc_sname_func)(rdesc)
205 uchar_t rtype = rdesc->rel_rtype;
206 #endif
207 const Rel_entry *rep;
208
209 rep = &reloc_table[rtype];
210
211 switch (rep->re_fsize) {
212 case 1:
213 /* LINTED */
214 *((uchar_t *)off) = (uchar_t)(*value);
215 break;
216
217 case 2:
218 #if defined(DORELOC_NATIVE)
219 /* LINTED */
220 *((Half *)off) = (Half)(*value);
221 #else
222 {
223 Half v = (Half)(*value);
224 uchar_t *v_bytes = (uchar_t *)&v;
225
226 if (bswap) {
227 UL_ASSIGN_BSWAP_HALF(off, v_bytes);
228 } else {
229 UL_ASSIGN_HALF(off, v_bytes);
230 }
231 }
232 #endif
233 break;
234
235 case 4:
236 /*
237 * The amd64 psABI requires that we perform the following
238 * verifications:
239 *
240 * The R_AMD64_32 and R_AMD64_32S relocations truncate the
241 * computed value to 32bits. Verify that the generated value
242 * for the R_AMD64_32/32S relocation zero-extends (sign
243 * extends) to the original 64-bit value.
244 *
245 * Also, the following relocations are all 32 bit PC relative
246 * references. Validate that the value being written will fit
247 * in the field provided.
248 *
249 * R_AMD64_PC32, R_AMD64_GOTPC32, R_AMD64_GOTPCREL
250 */
251 if (rtype == R_AMD64_32) {
252 /*
253 * Verify that this value will act as a zero-extended
254 * unsigned 32 bit value. That is, that the upper
255 * 32 bits are zero.
256 */
257 if ((*value & ZEROEXBITS) != 0) {
258 /*
259 * To keep chkmsg() happy:
260 * MSG_INTL(MSG_REL_NOFIT)
261 */
262 REL_ERR_NOFIT(lml, file, sym, rtype, *value);
263 return (0);
264 }
265 } else if ((rtype == R_AMD64_32S) || (rtype == R_AMD64_PC32) ||
266 (rtype == R_AMD64_GOTPCREL) || (rtype == R_AMD64_GOTPC32)) {
267 /*
268 * Verify that this value will act as a sign-extended
269 * signed 32 bit value, that is that the upper 33 bits
270 * are either all zero or all one.
271 */
272 if (((*value & SIGNEXBITS) != SIGNEXBITS) &&
273 ((*value & SIGNEXBITS) != 0)) {
274 /*
275 * To keep chkmsg() happy:
276 * MSG_INTL(MSG_REL_NOFIT)
277 */
278 REL_ERR_NOFIT(lml, file, sym, rtype, *value);
279 return (0);
280 }
281 }
282
283 #if defined(DORELOC_NATIVE)
284 /* LINTED */
285 *((Word *)off) += *value;
286 #else
287 {
288 Word v;
289 uchar_t *v_bytes = (uchar_t *)&v;
290
291 if (bswap) {
292 UL_ASSIGN_BSWAP_WORD(v_bytes, off);
293 v += *value;
294 UL_ASSIGN_BSWAP_WORD(off, v_bytes);
295 } else {
296 UL_ASSIGN_WORD(v_bytes, off);
297 v += *value;
298 UL_ASSIGN_WORD(off, v_bytes);
299 }
300 }
301 #endif
302 break;
303
304 case 8:
305 #if defined(DORELOC_NATIVE)
306 /* LINTED */
307 *((Xword *)off) += *value;
308 #else
309 {
310 Xword v;
311 uchar_t *v_bytes = (uchar_t *)&v;
312
313 if (bswap) {
314 UL_ASSIGN_BSWAP_XWORD(v_bytes, off);
315 v += *value;
316 UL_ASSIGN_BSWAP_XWORD(off, v_bytes);
317 } else {
318 UL_ASSIGN_XWORD(v_bytes, off);
319 v += *value;
320 UL_ASSIGN_XWORD(off, v_bytes);
321 }
322 }
323 #endif
324 break;
325 default:
326 /*
327 * To keep chkmsg() happy: MSG_INTL(MSG_REL_UNSUPSZ)
328 */
329 REL_ERR_UNSUPSZ(lml, file, sym, rtype, rep->re_fsize);
330 return (0);
331 }
332 return (1);
333
334 #ifdef DO_RELOC_LIBLD
335 #undef sym
336 #endif
337 }
338