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) 1995, 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_386
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_386_NUM] = {
64 /* R_386_NONE */ {0, FLG_RE_NOTREL, 0, 0, 0},
65 /* R_386_32 */ {0, FLG_RE_NOTREL, 4, 0, 0},
66 /* R_386_PC32 */ {0, FLG_RE_PCREL, 4, 0, 0},
67 /* R_386_GOT32 */ {0, FLG_RE_GOTADD, 4, 0, 0},
68 /* R_386_PLT32 */ {0, FLG_RE_PLTREL | FLG_RE_PCREL, 4, 0, 0},
69 /* R_386_COPY */ {0, FLG_RE_NOTREL, 0, 0, 0}, /* SPECIAL */
70 /* R_386_GLOB_DAT */ {0, FLG_RE_NOTREL, 4, 0, 0},
71 /* R_386_JMP_SLOT */ {0, FLG_RE_NOTREL, 4, 0, 0}, /* SPECIAL */
72 /* R_386_RELATIVE */ {0, FLG_RE_NOTREL, 4, 0, 0},
73 /* R_386_GOTOFF */ {0, FLG_RE_GOTREL, 4, 0, 0},
74 /* R_386_GOTPC */ {0, FLG_RE_PCREL | FLG_RE_GOTPC | FLG_RE_LOCLBND, 4,
75 0, 0},
76 /* R_386_32PLT */ {0, FLG_RE_PLTREL, 4, 0, 0},
77 /* R_386_TLS_GD_PLT */ {0, FLG_RE_PLTREL | FLG_RE_PCREL | FLG_RE_TLSGD, 4,
78 0, 0},
79 /* R_386_TLS_LDM_PLT */ {0, FLG_RE_PLTREL | FLG_RE_PCREL | FLG_RE_TLSLD, 4,
80 0, 0},
81 /* R_386_TLS_TPOFF */ {0, FLG_RE_NOTREL, 4, 0, 0},
82 /* R_386_TLS_IE */ {0, FLG_RE_GOTADD | FLG_RE_TLSIE, 4, 0, 0},
83 /* R_386_TLS_GOTIE */ {0, FLG_RE_GOTADD | FLG_RE_TLSIE, 4, 0, 0},
84 /* R_386_TLS_LE */ {0, FLG_RE_TLSLE, 4, 0, 0},
85 /* R_386_TLS_GD */ {0, FLG_RE_GOTADD | FLG_RE_TLSGD, 4, 0, 0},
86 /* R_386_TLS_LDM */ {0, FLG_RE_GOTADD | FLG_RE_TLSLD, 4, 0, 0},
87 /* R_386_16 */ {0, FLG_RE_NOTREL, 2, 0, 0},
88 /* R_386_PC16 */ {0, FLG_RE_PCREL, 2, 0, 0},
89 /* R_386_8 */ {0, FLG_RE_NOTREL, 1, 0, 0},
90 /* R_386_PC8 */ {0, FLG_RE_PCREL, 1, 0, 0},
91 /* R_386_UNKNOWN24 */ {0, FLG_RE_NOTSUP, 0, 0, 0},
92 /* R_386_UNKNOWN25 */ {0, FLG_RE_NOTSUP, 0, 0, 0},
93 /* R_386_UNKNOWN26 */ {0, FLG_RE_NOTSUP, 0, 0, 0},
94 /* R_386_UNKNOWN27 */ {0, FLG_RE_NOTSUP, 0, 0, 0},
95 /* R_386_UNKNOWN28 */ {0, FLG_RE_NOTSUP, 0, 0, 0},
96 /* R_386_UNKNOWN29 */ {0, FLG_RE_NOTSUP, 0, 0, 0},
97 /* R_386_UNKNOWN30 */ {0, FLG_RE_NOTSUP, 0, 0, 0},
98 /* R_386_UNKNOWN31 */ {0, FLG_RE_NOTSUP, 0, 0, 0},
99 /* R_386_TLS_LDO_32 */ {0, FLG_RE_TLSLD, 4, 0, 0},
100 /* R_386_UNKNOWN33 */ {0, FLG_RE_NOTSUP, 0, 0, 0},
101 /* R_386_UNKNOWN34 */ {0, FLG_RE_NOTSUP, 0, 0, 0},
102 /* R_386_TLS_DTPMOD32 */ {0, FLG_RE_NOTREL, 4, 0, 0},
103 /* R_386_TLS_DTPOFF32 */ {0, FLG_RE_NOTREL, 4, 0, 0},
104 /* R_386_UNKONWN37 */ {0, FLG_RE_NOTSUP, 0, 0, 0},
105 /* R_386_SIZE32 */ {0, FLG_RE_SIZE | FLG_RE_VERIFY, 4, 0, 0}
106 };
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_386_NONE 0 none none
116 * R_386_32 1 word32 S + A
117 * R_386_PC32 2 word32 S + A - P
118 * R_386_GOT32 3 word32 G + A - P
119 * R_386_PLT32 4 word32 L + A - P
120 * R_386_COPY 5 none none
121 * R_386_GLOB_DAT 6 word32 S
122 * R_386_JMP_SLOT 7 word32 S
123 * R_386_RELATIVE 8 word32 B + A
124 * R_386_GOTOFF 9 word32 S + A - GOT
125 * R_386_GOTPC 10 word32 GOT + A - P
126 * R_386_32PLT 11 word32 L + A
127 * R_386_TLS_GD_PLT 12 word32 @tlsgdplt
128 * R_386_TLS_LDM_PLT 13 word32 @tlsldmplt
129 * R_386_TLS_TPOFF 14 word32 @ntpoff(S)
130 * R_386_TLS_IE 15 word32 @indntpoff(S)
131 * R_386_TLS_GD 18 word32 @tlsgd(S)
132 * R_386_TLS_LDM 19 word32 @tlsldm(S)
133 * R_386_16 20 word16 S + A
134 * R_386_PC16 21 word16 S + A - P
135 * R_386_8 22 word8 S + A
136 * R_386_PC8 23 word8 S + A - P
137 * R_386_TLS_LDO_32 32 word32 @dtpoff(S)
138 * R_386_TLS_DTPMOD32 35 word32 @dtpmod(S)
139 * R_386_TLS_DTPOFF32 36 word32 @dtpoff(S)
140 * R_386_SIZE32 38 word32 Z + A
141 *
142 * Relocations 0-10 are from Figure 4-4: Relocation Types from the
143 * intel ABI. Relocation 11 (R_386_32PLT) is from the C++ intel abi
144 * and is in the process of being registered with intel ABI (1/13/94).
145 *
146 * Relocations R_386_TLS_* are added to support Thread-Local storage
147 * as recorded in PSARC/2001/509
148 *
149 * Relocation calculations:
150 *
151 * CALCULATION uses the following notation:
152 * A the addend used
153 * B the base address of the shared object in memory
154 * G the offset into the global offset table
155 * GOT the address of teh global offset table
156 * L the procedure linkage entry
157 * P the place of the storage unit being relocated
158 * S the value of the symbol
159 * Z the size of the symbol whose index resides in the relocation
160 * entry
161 *
162 * @dtlndx(x): Allocate two contiguous entries in the GOT table to hold
163 * a Tls_index structure (for passing to __tls_get_addr()). The
164 * instructions referencing this entry will be bound to the first
165 * of the two GOT entries.
166 *
167 * @tmndx(x): Allocate two contiguous entries in the GOT table to hold
168 * a Tls_index structure (for passing to __tls_get_addr()). The
169 * ti_offset field of the Tls_index will be set to 0 (zero) and the
170 * ti_module will be filled in at run-time. The call to
171 * __tls_get_addr() will return the starting offset of the dynamic
172 * TLS block.
173 *
174 * @dtpoff(x): calculate the tlsoffset relative to the TLS block.
175 *
176 * @tpoff(x): calculate the tlsoffset relative to the TLS block.
177 *
178 * @dtpmod(x): calculate the module id of the object containing symbol x.
179 *
180 * The calculations in the CALCULATION column are assumed to have
181 * been performed before calling this function except for the addition of
182 * the addresses in the instructions.
183 */
184 #if defined(_KERNEL)
185 #define lml 0 /* Needed by arglist of REL_ERR_* macros */
186 int
187 do_reloc_krtld(uchar_t rtype, uchar_t *off, Xword *value, const char *sym,
188 const char *file)
189 #elif defined(DO_RELOC_LIBLD)
190 /*ARGSUSED5*/
191 int
192 do_reloc_ld(Rel_desc *rdesc, uchar_t *off, Xword *value,
193 rel_desc_sname_func_t rel_desc_sname_func,
194 const char *file, int bswap, void *lml)
195 #else
196 int
197 do_reloc_rtld(uchar_t rtype, uchar_t *off, Xword *value, const char *sym,
198 const char *file, void *lml)
199 #endif
200 {
201 #ifdef DO_RELOC_LIBLD
202 #define sym (* rel_desc_sname_func)(rdesc)
203 uchar_t rtype = rdesc->rel_rtype;
204 #endif
205 const Rel_entry *rep;
206
207 rep = &reloc_table[rtype];
208
209 switch (rep->re_fsize) {
210 case 1:
211 /* LINTED */
212 *((uchar_t *)off) += (uchar_t)(*value);
213 break;
214
215 case 2:
216 #if defined(DORELOC_NATIVE)
217 /* LINTED */
218 *((Half *)off) += (Half)(*value);
219 #else
220 {
221 Half v;
222 uchar_t *v_bytes = (uchar_t *)&v;
223
224 if (bswap) {
225 UL_ASSIGN_BSWAP_HALF(v_bytes, off);
226 v += *value;
227 UL_ASSIGN_BSWAP_HALF(off, v_bytes);
228 } else {
229 UL_ASSIGN_HALF(v_bytes, off);
230 v += *value;
231 UL_ASSIGN_HALF(off, v_bytes);
232 }
233 }
234 #endif
235 break;
236
237 case 4:
238 #if defined(DORELOC_NATIVE)
239 /* LINTED */
240 *((Xword *)off) += *value;
241 #else
242 {
243 Word v;
244 uchar_t *v_bytes = (uchar_t *)&v;
245
246 if (bswap) {
247 UL_ASSIGN_BSWAP_WORD(v_bytes, off);
248 v += *value;
249 UL_ASSIGN_BSWAP_WORD(off, v_bytes);
250 } else {
251 UL_ASSIGN_WORD(v_bytes, off);
252 v += *value;
253 UL_ASSIGN_WORD(off, v_bytes);
254 }
255 }
256 #endif
257 break;
258 default:
259 /*
260 * To keep chkmsg() happy: MSG_INTL(MSG_REL_UNSUPSZ)
261 */
262 REL_ERR_UNSUPSZ(lml, file, sym, rtype, rep->re_fsize);
263 return (0);
264 }
265 return (1);
266
267 #ifdef DO_RELOC_LIBLD
268 #undef sym
269 #endif
270 }