mdreloc.c revision 1.71 1 1.71 uwe /* $NetBSD: mdreloc.c,v 1.71 2024/07/23 09:55:19 uwe Exp $ */
2 1.1 eeh
3 1.1 eeh /*-
4 1.1 eeh * Copyright (c) 2000 Eduardo Horvath.
5 1.23 mycroft * Copyright (c) 1999, 2002 The NetBSD Foundation, Inc.
6 1.1 eeh * All rights reserved.
7 1.1 eeh *
8 1.1 eeh * This code is derived from software contributed to The NetBSD Foundation
9 1.27 mycroft * by Paul Kranenburg and by Charles M. Hannum.
10 1.1 eeh *
11 1.1 eeh * Redistribution and use in source and binary forms, with or without
12 1.1 eeh * modification, are permitted provided that the following conditions
13 1.1 eeh * are met:
14 1.1 eeh * 1. Redistributions of source code must retain the above copyright
15 1.1 eeh * notice, this list of conditions and the following disclaimer.
16 1.1 eeh * 2. Redistributions in binary form must reproduce the above copyright
17 1.1 eeh * notice, this list of conditions and the following disclaimer in the
18 1.1 eeh * documentation and/or other materials provided with the distribution.
19 1.1 eeh *
20 1.1 eeh * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21 1.1 eeh * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22 1.1 eeh * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23 1.1 eeh * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24 1.1 eeh * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25 1.1 eeh * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26 1.1 eeh * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27 1.1 eeh * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28 1.1 eeh * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29 1.1 eeh * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30 1.1 eeh * POSSIBILITY OF SUCH DAMAGE.
31 1.1 eeh */
32 1.1 eeh
33 1.71 uwe /*
34 1.71 uwe * SPARC ELF relocations.
35 1.71 uwe *
36 1.71 uwe * Reference:
37 1.71 uwe *
38 1.71 uwe * SPARC Compliance Definition 2.4.1
39 1.71 uwe * http://sparc.org/wp-content/uploads/2014/01/SCD.2.4.1.pdf.gz
40 1.71 uwe */
41 1.71 uwe
42 1.37 skrll #include <sys/cdefs.h>
43 1.37 skrll #ifndef lint
44 1.71 uwe __RCSID("$NetBSD: mdreloc.c,v 1.71 2024/07/23 09:55:19 uwe Exp $");
45 1.37 skrll #endif /* not lint */
46 1.37 skrll
47 1.68 joerg #include <machine/elf_support.h>
48 1.68 joerg
49 1.1 eeh #include <errno.h>
50 1.1 eeh #include <stdio.h>
51 1.1 eeh #include <stdlib.h>
52 1.1 eeh #include <string.h>
53 1.1 eeh #include <unistd.h>
54 1.1 eeh
55 1.1 eeh #include "rtldenv.h"
56 1.1 eeh #include "debug.h"
57 1.1 eeh #include "rtld.h"
58 1.1 eeh
59 1.1 eeh /*
60 1.1 eeh * The following table holds for each relocation type:
61 1.1 eeh * - the width in bits of the memory location the relocation
62 1.1 eeh * applies to (not currently used)
63 1.1 eeh * - the number of bits the relocation value must be shifted to the
64 1.1 eeh * right (i.e. discard least significant bits) to fit into
65 1.1 eeh * the appropriate field in the instruction word.
66 1.1 eeh * - flags indicating whether
67 1.1 eeh * * the relocation involves a symbol
68 1.1 eeh * * the relocation is relative to the current position
69 1.1 eeh * * the relocation is for a GOT entry
70 1.1 eeh * * the relocation is relative to the load address
71 1.1 eeh *
72 1.1 eeh */
73 1.1 eeh #define _RF_S 0x80000000 /* Resolve symbol */
74 1.1 eeh #define _RF_A 0x40000000 /* Use addend */
75 1.1 eeh #define _RF_P 0x20000000 /* Location relative */
76 1.1 eeh #define _RF_G 0x10000000 /* GOT offset */
77 1.1 eeh #define _RF_B 0x08000000 /* Load address relative */
78 1.2 eeh #define _RF_U 0x04000000 /* Unaligned */
79 1.1 eeh #define _RF_SZ(s) (((s) & 0xff) << 8) /* memory target size */
80 1.1 eeh #define _RF_RS(s) ( (s) & 0xff) /* right shift */
81 1.52 martin static const int reloc_target_flags[R_TYPE(TLS_TPOFF64)+1] = {
82 1.1 eeh 0, /* NONE */
83 1.1 eeh _RF_S|_RF_A| _RF_SZ(8) | _RF_RS(0), /* RELOC_8 */
84 1.1 eeh _RF_S|_RF_A| _RF_SZ(16) | _RF_RS(0), /* RELOC_16 */
85 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* RELOC_32 */
86 1.1 eeh _RF_S|_RF_A|_RF_P| _RF_SZ(8) | _RF_RS(0), /* DISP_8 */
87 1.1 eeh _RF_S|_RF_A|_RF_P| _RF_SZ(16) | _RF_RS(0), /* DISP_16 */
88 1.1 eeh _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(0), /* DISP_32 */
89 1.1 eeh _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(2), /* WDISP_30 */
90 1.1 eeh _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(2), /* WDISP_22 */
91 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(10), /* HI22 */
92 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* 22 */
93 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* 13 */
94 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* LO10 */
95 1.1 eeh _RF_G| _RF_SZ(32) | _RF_RS(0), /* GOT10 */
96 1.1 eeh _RF_G| _RF_SZ(32) | _RF_RS(0), /* GOT13 */
97 1.1 eeh _RF_G| _RF_SZ(32) | _RF_RS(10), /* GOT22 */
98 1.1 eeh _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(0), /* PC10 */
99 1.1 eeh _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(10), /* PC22 */
100 1.1 eeh _RF_A|_RF_P| _RF_SZ(32) | _RF_RS(2), /* WPLT30 */
101 1.1 eeh _RF_SZ(32) | _RF_RS(0), /* COPY */
102 1.1 eeh _RF_S|_RF_A| _RF_SZ(64) | _RF_RS(0), /* GLOB_DAT */
103 1.1 eeh _RF_SZ(32) | _RF_RS(0), /* JMP_SLOT */
104 1.1 eeh _RF_A| _RF_B| _RF_SZ(64) | _RF_RS(0), /* RELATIVE */
105 1.2 eeh _RF_S|_RF_A| _RF_U| _RF_SZ(32) | _RF_RS(0), /* UA_32 */
106 1.1 eeh
107 1.1 eeh _RF_A| _RF_SZ(32) | _RF_RS(0), /* PLT32 */
108 1.1 eeh _RF_A| _RF_SZ(32) | _RF_RS(10), /* HIPLT22 */
109 1.1 eeh _RF_A| _RF_SZ(32) | _RF_RS(0), /* LOPLT10 */
110 1.1 eeh _RF_A|_RF_P| _RF_SZ(32) | _RF_RS(0), /* PCPLT32 */
111 1.1 eeh _RF_A|_RF_P| _RF_SZ(32) | _RF_RS(10), /* PCPLT22 */
112 1.1 eeh _RF_A|_RF_P| _RF_SZ(32) | _RF_RS(0), /* PCPLT10 */
113 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* 10 */
114 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* 11 */
115 1.1 eeh _RF_S|_RF_A| _RF_SZ(64) | _RF_RS(0), /* 64 */
116 1.1 eeh _RF_S|_RF_A|/*extra*/ _RF_SZ(32) | _RF_RS(0), /* OLO10 */
117 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(42), /* HH22 */
118 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(32), /* HM10 */
119 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(10), /* LM22 */
120 1.1 eeh _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(42), /* PC_HH22 */
121 1.1 eeh _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(32), /* PC_HM10 */
122 1.1 eeh _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(10), /* PC_LM22 */
123 1.1 eeh _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(2), /* WDISP16 */
124 1.1 eeh _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(2), /* WDISP19 */
125 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* GLOB_JMP */
126 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* 7 */
127 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* 5 */
128 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* 6 */
129 1.1 eeh _RF_S|_RF_A|_RF_P| _RF_SZ(64) | _RF_RS(0), /* DISP64 */
130 1.1 eeh _RF_A| _RF_SZ(64) | _RF_RS(0), /* PLT64 */
131 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(10), /* HIX22 */
132 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* LOX10 */
133 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(22), /* H44 */
134 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(12), /* M44 */
135 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* L44 */
136 1.1 eeh _RF_S|_RF_A| _RF_SZ(64) | _RF_RS(0), /* REGISTER */
137 1.2 eeh _RF_S|_RF_A| _RF_U| _RF_SZ(64) | _RF_RS(0), /* UA64 */
138 1.2 eeh _RF_S|_RF_A| _RF_U| _RF_SZ(16) | _RF_RS(0), /* UA16 */
139 1.52 martin /* TLS relocs not represented here! */
140 1.1 eeh };
141 1.1 eeh
142 1.1 eeh #ifdef RTLD_DEBUG_RELOC
143 1.1 eeh static const char *reloc_names[] = {
144 1.1 eeh "NONE", "RELOC_8", "RELOC_16", "RELOC_32", "DISP_8",
145 1.1 eeh "DISP_16", "DISP_32", "WDISP_30", "WDISP_22", "HI22",
146 1.1 eeh "22", "13", "LO10", "GOT10", "GOT13",
147 1.1 eeh "GOT22", "PC10", "PC22", "WPLT30", "COPY",
148 1.1 eeh "GLOB_DAT", "JMP_SLOT", "RELATIVE", "UA_32", "PLT32",
149 1.1 eeh "HIPLT22", "LOPLT10", "LOPLT10", "PCPLT22", "PCPLT32",
150 1.1 eeh "10", "11", "64", "OLO10", "HH22",
151 1.1 eeh "HM10", "LM22", "PC_HH22", "PC_HM10", "PC_LM22",
152 1.1 eeh "WDISP16", "WDISP19", "GLOB_JMP", "7", "5", "6",
153 1.1 eeh "DISP64", "PLT64", "HIX22", "LOX10", "H44", "M44",
154 1.52 martin "L44", "REGISTER", "UA64", "UA16",
155 1.52 martin "TLS_GD_HI22", "TLS_GD_LO10", "TLS_GD_ADD", "TLS_GD_CALL",
156 1.52 martin "TLS_LDM_HI22", "TLS_LDM_LO10", "TLS_LDM_ADD", "TLS_LDM_CALL",
157 1.52 martin "TLS_LDO_HIX22", "TLS_LDO_LOX10", "TLS_LDO_ADD", "TLS_IE_HI22",
158 1.52 martin "TLS_IE_LO10", "TLS_IE_LD", "TLS_IE_LDX", "TLS_IE_ADD", "TLS_LE_HIX22",
159 1.52 martin "TLS_LE_LOX10", "TLS_DTPMOD32", "TLS_DTPMOD64", "TLS_DTPOFF32",
160 1.52 martin "TLS_DTPOFF64", "TLS_TPOFF32", "TLS_TPOFF64",
161 1.1 eeh };
162 1.1 eeh #endif
163 1.1 eeh
164 1.1 eeh #define RELOC_RESOLVE_SYMBOL(t) ((reloc_target_flags[t] & _RF_S) != 0)
165 1.1 eeh #define RELOC_PC_RELATIVE(t) ((reloc_target_flags[t] & _RF_P) != 0)
166 1.1 eeh #define RELOC_BASE_RELATIVE(t) ((reloc_target_flags[t] & _RF_B) != 0)
167 1.2 eeh #define RELOC_UNALIGNED(t) ((reloc_target_flags[t] & _RF_U) != 0)
168 1.2 eeh #define RELOC_USE_ADDEND(t) ((reloc_target_flags[t] & _RF_A) != 0)
169 1.1 eeh #define RELOC_TARGET_SIZE(t) ((reloc_target_flags[t] >> 8) & 0xff)
170 1.1 eeh #define RELOC_VALUE_RIGHTSHIFT(t) (reloc_target_flags[t] & 0xff)
171 1.52 martin #define RELOC_TLS(t) (t >= R_TYPE(TLS_GD_HI22))
172 1.1 eeh
173 1.16 mycroft static const long reloc_target_bitmask[] = {
174 1.1 eeh #define _BM(x) (~(-(1ULL << (x))))
175 1.1 eeh 0, /* NONE */
176 1.1 eeh _BM(8), _BM(16), _BM(32), /* RELOC_8, _16, _32 */
177 1.1 eeh _BM(8), _BM(16), _BM(32), /* DISP8, DISP16, DISP32 */
178 1.1 eeh _BM(30), _BM(22), /* WDISP30, WDISP22 */
179 1.1 eeh _BM(22), _BM(22), /* HI22, _22 */
180 1.1 eeh _BM(13), _BM(10), /* RELOC_13, _LO10 */
181 1.1 eeh _BM(10), _BM(13), _BM(22), /* GOT10, GOT13, GOT22 */
182 1.1 eeh _BM(10), _BM(22), /* _PC10, _PC22 */
183 1.1 eeh _BM(30), 0, /* _WPLT30, _COPY */
184 1.56 martin -1, _BM(32), -1, /* _GLOB_DAT, JMP_SLOT, _RELATIVE */
185 1.1 eeh _BM(32), _BM(32), /* _UA32, PLT32 */
186 1.1 eeh _BM(22), _BM(10), /* _HIPLT22, LOPLT10 */
187 1.1 eeh _BM(32), _BM(22), _BM(10), /* _PCPLT32, _PCPLT22, _PCPLT10 */
188 1.1 eeh _BM(10), _BM(11), -1, /* _10, _11, _64 */
189 1.59 martin _BM(13), _BM(22), /* _OLO10, _HH22 */
190 1.1 eeh _BM(10), _BM(22), /* _HM10, _LM22 */
191 1.1 eeh _BM(22), _BM(10), _BM(22), /* _PC_HH22, _PC_HM10, _PC_LM22 */
192 1.1 eeh _BM(16), _BM(19), /* _WDISP16, _WDISP19 */
193 1.1 eeh -1, /* GLOB_JMP */
194 1.54 martin _BM(7), _BM(5), _BM(6), /* _7, _5, _6 */
195 1.1 eeh -1, -1, /* DISP64, PLT64 */
196 1.1 eeh _BM(22), _BM(13), /* HIX22, LOX10 */
197 1.55 martin _BM(22), _BM(10), _BM(12), /* H44, M44, L44 */
198 1.1 eeh -1, -1, _BM(16), /* REGISTER, UA64, UA16 */
199 1.1 eeh #undef _BM
200 1.1 eeh };
201 1.1 eeh #define RELOC_VALUE_BITMASK(t) (reloc_target_bitmask[t])
202 1.1 eeh
203 1.1 eeh /*
204 1.1 eeh * Instruction templates:
205 1.1 eeh */
206 1.1 eeh
207 1.1 eeh
208 1.26 mycroft /* %hi(v)/%lo(v) with variable shift */
209 1.26 mycroft #define HIVAL(v, s) (((v) >> (s)) & 0x003fffff)
210 1.26 mycroft #define LOVAL(v, s) (((v) >> (s)) & 0x000003ff)
211 1.1 eeh
212 1.20 mycroft void _rtld_bind_start_0(long, long);
213 1.20 mycroft void _rtld_bind_start_1(long, long);
214 1.18 mycroft void _rtld_relocate_nonplt_self(Elf_Dyn *, Elf_Addr);
215 1.34 skrll caddr_t _rtld_bind(const Obj_Entry *, Elf_Word);
216 1.1 eeh
217 1.1 eeh /*
218 1.1 eeh * Install rtld function call into this PLT slot.
219 1.1 eeh */
220 1.29 mycroft #define SAVE 0x9de3bf50 /* i.e. `save %sp,-176,%sp' */
221 1.1 eeh #define SETHI_l0 0x21000000
222 1.1 eeh #define SETHI_l1 0x23000000
223 1.1 eeh #define OR_l0_l0 0xa0142000
224 1.1 eeh #define SLLX_l0_32_l0 0xa12c3020
225 1.1 eeh #define OR_l0_l1_l0 0xa0140011
226 1.26 mycroft #define JMPL_l0_o0 0x91c42000
227 1.26 mycroft #define MOV_g1_o1 0x92100001
228 1.1 eeh
229 1.36 skrll void _rtld_install_plt(Elf_Word *, Elf_Addr);
230 1.36 skrll static inline int _rtld_relocate_plt_object(const Obj_Entry *,
231 1.36 skrll const Elf_Rela *, Elf_Addr *);
232 1.1 eeh
233 1.1 eeh void
234 1.34 skrll _rtld_install_plt(Elf_Word *pltgot, Elf_Addr proc)
235 1.1 eeh {
236 1.1 eeh pltgot[0] = SAVE;
237 1.1 eeh pltgot[1] = SETHI_l0 | HIVAL(proc, 42);
238 1.1 eeh pltgot[2] = SETHI_l1 | HIVAL(proc, 10);
239 1.26 mycroft pltgot[3] = OR_l0_l0 | LOVAL(proc, 32);
240 1.1 eeh pltgot[4] = SLLX_l0_32_l0;
241 1.1 eeh pltgot[5] = OR_l0_l1_l0;
242 1.26 mycroft pltgot[6] = JMPL_l0_o0 | LOVAL(proc, 0);
243 1.26 mycroft pltgot[7] = MOV_g1_o1;
244 1.1 eeh }
245 1.2 eeh
246 1.6 mycroft void
247 1.6 mycroft _rtld_setup_pltgot(const Obj_Entry *obj)
248 1.6 mycroft {
249 1.6 mycroft /*
250 1.6 mycroft * On sparc64 we got troubles.
251 1.6 mycroft *
252 1.6 mycroft * Instructions are 4 bytes long.
253 1.6 mycroft * Elf[64]_Addr is 8 bytes long, so are our pltglot[]
254 1.6 mycroft * array entries.
255 1.6 mycroft * Each PLT entry jumps to PLT0 to enter the dynamic
256 1.6 mycroft * linker.
257 1.6 mycroft * Loading an arbitrary 64-bit pointer takes 6
258 1.6 mycroft * instructions and 2 registers.
259 1.6 mycroft *
260 1.6 mycroft * Somehow we need to issue a save to get a new stack
261 1.6 mycroft * frame, load the address of the dynamic linker, and
262 1.6 mycroft * jump there, in 8 instructions or less.
263 1.6 mycroft *
264 1.6 mycroft * Oh, we need to fill out both PLT0 and PLT1.
265 1.6 mycroft */
266 1.6 mycroft {
267 1.6 mycroft Elf_Word *entry = (Elf_Word *)obj->pltgot;
268 1.6 mycroft
269 1.6 mycroft /* Install in entries 0 and 1 */
270 1.6 mycroft _rtld_install_plt(&entry[0], (Elf_Addr) &_rtld_bind_start_0);
271 1.6 mycroft _rtld_install_plt(&entry[8], (Elf_Addr) &_rtld_bind_start_1);
272 1.6 mycroft
273 1.6 mycroft /*
274 1.6 mycroft * Install the object reference in first slot
275 1.6 mycroft * of entry 2.
276 1.6 mycroft */
277 1.6 mycroft obj->pltgot[8] = (Elf_Addr) obj;
278 1.6 mycroft }
279 1.8 mycroft }
280 1.8 mycroft
281 1.18 mycroft void
282 1.34 skrll _rtld_relocate_nonplt_self(Elf_Dyn *dynp, Elf_Addr relocbase)
283 1.18 mycroft {
284 1.18 mycroft const Elf_Rela *rela = 0, *relalim;
285 1.18 mycroft Elf_Addr relasz = 0;
286 1.18 mycroft Elf_Addr *where;
287 1.18 mycroft
288 1.18 mycroft for (; dynp->d_tag != DT_NULL; dynp++) {
289 1.18 mycroft switch (dynp->d_tag) {
290 1.18 mycroft case DT_RELA:
291 1.18 mycroft rela = (const Elf_Rela *)(relocbase + dynp->d_un.d_ptr);
292 1.18 mycroft break;
293 1.18 mycroft case DT_RELASZ:
294 1.18 mycroft relasz = dynp->d_un.d_val;
295 1.18 mycroft break;
296 1.18 mycroft }
297 1.18 mycroft }
298 1.44 lukem relalim = (const Elf_Rela *)((const uint8_t *)rela + relasz);
299 1.18 mycroft for (; rela < relalim; rela++) {
300 1.18 mycroft where = (Elf_Addr *)(relocbase + rela->r_offset);
301 1.18 mycroft *where = (Elf_Addr)(relocbase + rela->r_addend);
302 1.18 mycroft }
303 1.18 mycroft }
304 1.18 mycroft
305 1.8 mycroft int
306 1.47 joerg _rtld_relocate_nonplt_objects(Obj_Entry *obj)
307 1.8 mycroft {
308 1.9 mycroft const Elf_Rela *rela;
309 1.40 martin const Elf_Sym *def = NULL;
310 1.40 martin const Obj_Entry *defobj = NULL;
311 1.61 joerg unsigned long last_symnum = ULONG_MAX;
312 1.18 mycroft
313 1.9 mycroft for (rela = obj->rela; rela < obj->relalim; rela++) {
314 1.9 mycroft Elf_Addr *where;
315 1.9 mycroft Elf_Word type;
316 1.9 mycroft Elf_Addr value = 0, mask;
317 1.61 joerg unsigned long symnum;
318 1.9 mycroft
319 1.9 mycroft where = (Elf_Addr *) (obj->relocbase + rela->r_offset);
320 1.9 mycroft
321 1.9 mycroft type = ELF_R_TYPE(rela->r_info);
322 1.9 mycroft if (type == R_TYPE(NONE))
323 1.12 mycroft continue;
324 1.9 mycroft
325 1.53 martin /* OLO10 relocations have extra info */
326 1.53 martin if ((type & 0x00ff) == R_SPARC_OLO10)
327 1.53 martin type = R_SPARC_OLO10;
328 1.53 martin
329 1.23 mycroft /* We do JMP_SLOTs in _rtld_bind() below */
330 1.9 mycroft if (type == R_TYPE(JMP_SLOT))
331 1.12 mycroft continue;
332 1.9 mycroft
333 1.65 joerg /* IFUNC relocations are handled in _rtld_call_ifunc */
334 1.65 joerg if (type == R_TYPE(IRELATIVE)) {
335 1.69 joerg if (obj->ifunc_remaining_nonplt == 0) {
336 1.69 joerg obj->ifunc_remaining_nonplt =
337 1.69 joerg obj->relalim - rela;
338 1.69 joerg }
339 1.65 joerg continue;
340 1.65 joerg }
341 1.65 joerg
342 1.9 mycroft /* COPY relocs are also handled elsewhere */
343 1.9 mycroft if (type == R_TYPE(COPY))
344 1.12 mycroft continue;
345 1.8 mycroft
346 1.9 mycroft /*
347 1.9 mycroft * We use the fact that relocation types are an `enum'
348 1.52 martin * Note: R_SPARC_TLS_TPOFF64 is currently numerically largest.
349 1.9 mycroft */
350 1.53 martin if (type > R_TYPE(TLS_TPOFF64)) {
351 1.53 martin dbg(("unknown relocation type %x at %p", type, rela));
352 1.53 martin return -1;
353 1.53 martin }
354 1.8 mycroft
355 1.9 mycroft value = rela->r_addend;
356 1.8 mycroft
357 1.61 joerg if (RELOC_RESOLVE_SYMBOL(type) || RELOC_TLS(type)) {
358 1.61 joerg symnum = ELF_R_SYM(rela->r_info);
359 1.61 joerg if (last_symnum != symnum) {
360 1.61 joerg last_symnum = symnum;
361 1.61 joerg def = _rtld_find_symdef(symnum, obj, &defobj,
362 1.61 joerg false);
363 1.61 joerg if (def == NULL)
364 1.61 joerg return -1;
365 1.61 joerg }
366 1.61 joerg }
367 1.61 joerg
368 1.9 mycroft /*
369 1.52 martin * Handle TLS relocations here, they are different.
370 1.52 martin */
371 1.52 martin if (RELOC_TLS(type)) {
372 1.52 martin switch (type) {
373 1.60 joerg case R_TYPE(TLS_DTPMOD64):
374 1.60 joerg *where = (Elf64_Addr)defobj->tlsindex;
375 1.60 joerg
376 1.60 joerg rdbg(("TLS_DTPMOD64 %s in %s --> %p",
377 1.60 joerg obj->strtab +
378 1.60 joerg obj->symtab[symnum].st_name,
379 1.60 joerg obj->path, (void *)*where));
380 1.60 joerg
381 1.60 joerg break;
382 1.60 joerg
383 1.60 joerg case R_TYPE(TLS_DTPOFF64):
384 1.60 joerg *where = (Elf64_Addr)(def->st_value
385 1.60 joerg + rela->r_addend);
386 1.60 joerg
387 1.60 joerg rdbg(("DTPOFF64 %s in %s --> %p",
388 1.60 joerg obj->strtab +
389 1.60 joerg obj->symtab[symnum].st_name,
390 1.60 joerg obj->path, (void *)*where));
391 1.60 joerg
392 1.60 joerg break;
393 1.60 joerg
394 1.60 joerg case R_TYPE(TLS_TPOFF64):
395 1.70 joerg if (!defobj->tls_static &&
396 1.70 joerg _rtld_tls_offset_allocate(__UNCONST(defobj)))
397 1.70 joerg return -1;
398 1.60 joerg
399 1.60 joerg *where = (Elf64_Addr)(def->st_value -
400 1.60 joerg defobj->tlsoffset + rela->r_addend);
401 1.60 joerg
402 1.60 joerg rdbg(("TLS_TPOFF64 %s in %s --> %p",
403 1.60 joerg obj->strtab + obj->symtab[symnum].st_name,
404 1.60 joerg obj->path, (void *)*where));
405 1.52 martin
406 1.60 joerg break;
407 1.52 martin }
408 1.52 martin continue;
409 1.52 martin }
410 1.52 martin
411 1.52 martin /*
412 1.18 mycroft * Handle relative relocs here, as an optimization.
413 1.9 mycroft */
414 1.17 mycroft if (type == R_TYPE(RELATIVE)) {
415 1.9 mycroft *where = (Elf_Addr)(obj->relocbase + value);
416 1.21 mycroft rdbg(("RELATIVE in %s --> %p", obj->path,
417 1.18 mycroft (void *)*where));
418 1.12 mycroft continue;
419 1.9 mycroft }
420 1.8 mycroft
421 1.9 mycroft if (RELOC_RESOLVE_SYMBOL(type)) {
422 1.9 mycroft /* Add in the symbol's absolute address */
423 1.9 mycroft value += (Elf_Addr)(defobj->relocbase + def->st_value);
424 1.9 mycroft }
425 1.8 mycroft
426 1.53 martin if (type == R_SPARC_OLO10) {
427 1.53 martin value = (value & 0x3ff)
428 1.53 martin + (((Elf64_Xword)rela->r_info<<32)>>40);
429 1.53 martin }
430 1.53 martin
431 1.9 mycroft if (RELOC_PC_RELATIVE(type)) {
432 1.9 mycroft value -= (Elf_Addr)where;
433 1.9 mycroft }
434 1.8 mycroft
435 1.9 mycroft if (RELOC_BASE_RELATIVE(type)) {
436 1.9 mycroft /*
437 1.9 mycroft * Note that even though sparcs use `Elf_rela'
438 1.9 mycroft * exclusively we still need the implicit memory addend
439 1.9 mycroft * in relocations referring to GOT entries.
440 1.9 mycroft * Undoubtedly, someone f*cked this up in the distant
441 1.9 mycroft * past, and now we're stuck with it in the name of
442 1.9 mycroft * compatibility for all eternity..
443 1.9 mycroft *
444 1.9 mycroft * In any case, the implicit and explicit should be
445 1.9 mycroft * mutually exclusive. We provide a check for that
446 1.9 mycroft * here.
447 1.9 mycroft */
448 1.8 mycroft #ifdef DIAGNOSTIC
449 1.9 mycroft if (value != 0 && *where != 0) {
450 1.9 mycroft xprintf("BASE_REL(%s): where=%p, *where 0x%lx, "
451 1.9 mycroft "addend=0x%lx, base %p\n",
452 1.9 mycroft obj->path, where, *where,
453 1.9 mycroft rela->r_addend, obj->relocbase);
454 1.9 mycroft }
455 1.9 mycroft #endif
456 1.9 mycroft /* XXXX -- apparently we ignore the preexisting value */
457 1.9 mycroft value += (Elf_Addr)(obj->relocbase);
458 1.8 mycroft }
459 1.8 mycroft
460 1.9 mycroft mask = RELOC_VALUE_BITMASK(type);
461 1.9 mycroft value >>= RELOC_VALUE_RIGHTSHIFT(type);
462 1.9 mycroft value &= mask;
463 1.9 mycroft
464 1.9 mycroft if (RELOC_UNALIGNED(type)) {
465 1.9 mycroft /* Handle unaligned relocations. */
466 1.9 mycroft Elf_Addr tmp = 0;
467 1.9 mycroft char *ptr = (char *)where;
468 1.9 mycroft int i, size = RELOC_TARGET_SIZE(type)/8;
469 1.9 mycroft
470 1.9 mycroft /* Read it in one byte at a time. */
471 1.9 mycroft for (i=0; i<size; i++)
472 1.9 mycroft tmp = (tmp << 8) | ptr[i];
473 1.9 mycroft
474 1.9 mycroft tmp &= ~mask;
475 1.9 mycroft tmp |= value;
476 1.9 mycroft
477 1.9 mycroft /* Write it back out. */
478 1.9 mycroft for (i=0; i<size; i++)
479 1.9 mycroft ptr[i] = ((tmp >> (8*i)) & 0xff);
480 1.8 mycroft #ifdef RTLD_DEBUG_RELOC
481 1.9 mycroft value = (Elf_Addr)tmp;
482 1.8 mycroft #endif
483 1.8 mycroft
484 1.9 mycroft } else if (RELOC_TARGET_SIZE(type) > 32) {
485 1.9 mycroft *where &= ~mask;
486 1.9 mycroft *where |= value;
487 1.8 mycroft #ifdef RTLD_DEBUG_RELOC
488 1.9 mycroft value = (Elf_Addr)*where;
489 1.8 mycroft #endif
490 1.9 mycroft } else {
491 1.9 mycroft Elf32_Addr *where32 = (Elf32_Addr *)where;
492 1.8 mycroft
493 1.9 mycroft *where32 &= ~mask;
494 1.9 mycroft *where32 |= value;
495 1.8 mycroft #ifdef RTLD_DEBUG_RELOC
496 1.9 mycroft value = (Elf_Addr)*where32;
497 1.8 mycroft #endif
498 1.9 mycroft }
499 1.8 mycroft
500 1.8 mycroft #ifdef RTLD_DEBUG_RELOC
501 1.9 mycroft if (RELOC_RESOLVE_SYMBOL(type)) {
502 1.21 mycroft rdbg(("%s %s in %s --> %p in %s", reloc_names[type],
503 1.11 mycroft obj->strtab + obj->symtab[symnum].st_name,
504 1.33 petrov obj->path, (void *)value, defobj->path));
505 1.11 mycroft } else {
506 1.21 mycroft rdbg(("%s in %s --> %p", reloc_names[type],
507 1.33 petrov obj->path, (void *)value));
508 1.9 mycroft }
509 1.9 mycroft #endif
510 1.8 mycroft }
511 1.13 mycroft return (0);
512 1.13 mycroft }
513 1.13 mycroft
514 1.13 mycroft int
515 1.64 joerg _rtld_relocate_plt_lazy(Obj_Entry *obj)
516 1.13 mycroft {
517 1.65 joerg const Elf_Rela *rela;
518 1.65 joerg
519 1.65 joerg for (rela = obj->pltrelalim; rela-- > obj->pltrela; ) {
520 1.65 joerg if (ELF_R_TYPE(rela->r_info) == R_TYPE(JMP_IREL))
521 1.65 joerg obj->ifunc_remaining = obj->pltrelalim - rela + 1;
522 1.65 joerg }
523 1.65 joerg
524 1.65 joerg return 0;
525 1.23 mycroft }
526 1.23 mycroft
527 1.23 mycroft caddr_t
528 1.34 skrll _rtld_bind(const Obj_Entry *obj, Elf_Word reloff)
529 1.23 mycroft {
530 1.24 mycroft const Elf_Rela *rela = obj->pltrela + reloff;
531 1.35 martin Elf_Addr result;
532 1.35 martin int err;
533 1.23 mycroft
534 1.39 mrg result = 0; /* XXX gcc */
535 1.39 mrg
536 1.67 joerg if (ELF_R_TYPE(obj->pltrela->r_info) == R_TYPE(JMP_SLOT) ||
537 1.67 joerg ELF_R_TYPE(obj->pltrela->r_info) == R_TYPE(JMP_IREL)) {
538 1.23 mycroft /*
539 1.23 mycroft * XXXX
540 1.23 mycroft *
541 1.23 mycroft * The first four PLT entries are reserved. There is some
542 1.23 mycroft * disagreement whether they should have associated relocation
543 1.23 mycroft * entries. Both the SPARC 32-bit and 64-bit ELF
544 1.23 mycroft * specifications say that they should have relocation entries,
545 1.23 mycroft * but the 32-bit SPARC binutils do not generate them, and now
546 1.23 mycroft * the 64-bit SPARC binutils have stopped generating them too.
547 1.23 mycroft *
548 1.23 mycroft * So, to provide binary compatibility, we will check the first
549 1.23 mycroft * entry, if it is reserved it should not be of the type
550 1.67 joerg * JMP_SLOT or JMP_REL. If it is either of those, then
551 1.67 joerg * the 4 reserved entries were not generated and our index
552 1.67 joerg * is 4 entries too far.
553 1.23 mycroft */
554 1.23 mycroft rela -= 4;
555 1.23 mycroft }
556 1.32 thorpej
557 1.51 joerg _rtld_shared_enter();
558 1.35 martin err = _rtld_relocate_plt_object(obj, rela, &result);
559 1.46 christos if (err)
560 1.35 martin _rtld_die();
561 1.51 joerg _rtld_shared_exit();
562 1.35 martin
563 1.35 martin return (caddr_t)result;
564 1.35 martin }
565 1.35 martin
566 1.35 martin int
567 1.35 martin _rtld_relocate_plt_objects(const Obj_Entry *obj)
568 1.35 martin {
569 1.35 martin const Elf_Rela *rela;
570 1.35 martin
571 1.35 martin rela = obj->pltrela;
572 1.35 martin
573 1.35 martin /*
574 1.35 martin * Check for first four reserved entries - and skip them.
575 1.35 martin * See above for details.
576 1.35 martin */
577 1.67 joerg if (ELF_R_TYPE(obj->pltrela->r_info) != R_TYPE(JMP_SLOT) &&
578 1.67 joerg ELF_R_TYPE(obj->pltrela->r_info) != R_TYPE(JMP_IREL))
579 1.35 martin rela += 4;
580 1.35 martin
581 1.35 martin for (; rela < obj->pltrelalim; rela++)
582 1.35 martin if (_rtld_relocate_plt_object(obj, rela, NULL) < 0)
583 1.35 martin return -1;
584 1.35 martin
585 1.35 martin return 0;
586 1.35 martin }
587 1.35 martin
588 1.65 joerg static inline void
589 1.65 joerg _rtld_write_plt(Elf_Word *where, Elf_Addr value, const Elf_Rela *rela,
590 1.65 joerg const Obj_Entry *obj)
591 1.35 martin {
592 1.65 joerg if (rela && rela->r_addend) {
593 1.23 mycroft Elf_Addr *ptr = (Elf_Addr *)where;
594 1.23 mycroft /*
595 1.48 skrll * This entry is >= 32768. The relocations points to a
596 1.28 mycroft * PC-relative pointer to the bind_0 stub at the top of the
597 1.28 mycroft * PLT section. Update it to point to the target function.
598 1.23 mycroft */
599 1.27 mycroft ptr[0] += value - (Elf_Addr)obj->pltgot;
600 1.23 mycroft } else {
601 1.68 joerg sparc_write_branch(where + 1, (void *)value);
602 1.65 joerg }
603 1.65 joerg }
604 1.65 joerg
605 1.65 joerg /*
606 1.65 joerg * New inline function that is called by _rtld_relocate_plt_object and
607 1.65 joerg * _rtld_bind
608 1.65 joerg */
609 1.65 joerg static inline int
610 1.65 joerg _rtld_relocate_plt_object(const Obj_Entry *obj, const Elf_Rela *rela,
611 1.65 joerg Elf_Addr *tp)
612 1.65 joerg {
613 1.65 joerg Elf_Word *where = (Elf_Word *)(obj->relocbase + rela->r_offset);
614 1.65 joerg const Elf_Sym *def;
615 1.65 joerg const Obj_Entry *defobj;
616 1.65 joerg Elf_Addr value;
617 1.65 joerg unsigned long info = rela->r_info;
618 1.65 joerg
619 1.65 joerg if (ELF_R_TYPE(info) == R_TYPE(JMP_IREL))
620 1.65 joerg return 0;
621 1.65 joerg
622 1.65 joerg assert(ELF_R_TYPE(info) == R_TYPE(JMP_SLOT));
623 1.65 joerg
624 1.65 joerg def = _rtld_find_plt_symdef(ELF_R_SYM(info), obj, &defobj, tp != NULL);
625 1.65 joerg if (__predict_false(def == NULL))
626 1.65 joerg return -1;
627 1.65 joerg if (__predict_false(def == &_rtld_sym_zero))
628 1.65 joerg return 0;
629 1.23 mycroft
630 1.65 joerg if (ELF_ST_TYPE(def->st_info) == STT_GNU_IFUNC) {
631 1.65 joerg if (tp == NULL)
632 1.65 joerg return 0;
633 1.65 joerg value = _rtld_resolve_ifunc(defobj, def);
634 1.65 joerg } else {
635 1.65 joerg value = (Elf_Addr)(defobj->relocbase + def->st_value);
636 1.23 mycroft }
637 1.65 joerg rdbg(("bind now/fixup in %s at %p --> new=%p",
638 1.65 joerg defobj->strtab + def->st_name, (void*)where, (void *)value));
639 1.65 joerg
640 1.65 joerg _rtld_write_plt(where, value, rela, obj);
641 1.23 mycroft
642 1.35 martin if (tp)
643 1.35 martin *tp = value;
644 1.35 martin
645 1.35 martin return 0;
646 1.6 mycroft }
647