mdreloc.c revision 1.10 1 1.10 mycroft /* $NetBSD: mdreloc.c,v 1.10 2002/09/05 21:21:12 mycroft Exp $ */
2 1.1 eeh
3 1.1 eeh /*-
4 1.1 eeh * Copyright (c) 2000 Eduardo Horvath.
5 1.1 eeh * Copyright (c) 1999 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 1.1 eeh * by Paul Kranenburg.
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 * 3. All advertising materials mentioning features or use of this software
20 1.1 eeh * must display the following acknowledgement:
21 1.1 eeh * This product includes software developed by the NetBSD
22 1.1 eeh * Foundation, Inc. and its contributors.
23 1.1 eeh * 4. Neither the name of The NetBSD Foundation nor the names of its
24 1.1 eeh * contributors may be used to endorse or promote products derived
25 1.1 eeh * from this software without specific prior written permission.
26 1.1 eeh *
27 1.1 eeh * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
28 1.1 eeh * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
29 1.1 eeh * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30 1.1 eeh * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
31 1.1 eeh * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32 1.1 eeh * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33 1.1 eeh * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34 1.1 eeh * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35 1.1 eeh * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36 1.1 eeh * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37 1.1 eeh * POSSIBILITY OF SUCH DAMAGE.
38 1.1 eeh */
39 1.1 eeh
40 1.1 eeh #include <errno.h>
41 1.1 eeh #include <stdio.h>
42 1.1 eeh #include <stdlib.h>
43 1.1 eeh #include <string.h>
44 1.1 eeh #include <unistd.h>
45 1.1 eeh #include <sys/stat.h>
46 1.1 eeh
47 1.1 eeh #include "rtldenv.h"
48 1.1 eeh #include "debug.h"
49 1.1 eeh #include "rtld.h"
50 1.1 eeh
51 1.1 eeh /*
52 1.1 eeh * The following table holds for each relocation type:
53 1.1 eeh * - the width in bits of the memory location the relocation
54 1.1 eeh * applies to (not currently used)
55 1.1 eeh * - the number of bits the relocation value must be shifted to the
56 1.1 eeh * right (i.e. discard least significant bits) to fit into
57 1.1 eeh * the appropriate field in the instruction word.
58 1.1 eeh * - flags indicating whether
59 1.1 eeh * * the relocation involves a symbol
60 1.1 eeh * * the relocation is relative to the current position
61 1.1 eeh * * the relocation is for a GOT entry
62 1.1 eeh * * the relocation is relative to the load address
63 1.1 eeh *
64 1.1 eeh */
65 1.1 eeh #define _RF_S 0x80000000 /* Resolve symbol */
66 1.1 eeh #define _RF_A 0x40000000 /* Use addend */
67 1.1 eeh #define _RF_P 0x20000000 /* Location relative */
68 1.1 eeh #define _RF_G 0x10000000 /* GOT offset */
69 1.1 eeh #define _RF_B 0x08000000 /* Load address relative */
70 1.2 eeh #define _RF_U 0x04000000 /* Unaligned */
71 1.1 eeh #define _RF_SZ(s) (((s) & 0xff) << 8) /* memory target size */
72 1.1 eeh #define _RF_RS(s) ( (s) & 0xff) /* right shift */
73 1.1 eeh static int reloc_target_flags[] = {
74 1.1 eeh 0, /* NONE */
75 1.1 eeh _RF_S|_RF_A| _RF_SZ(8) | _RF_RS(0), /* RELOC_8 */
76 1.1 eeh _RF_S|_RF_A| _RF_SZ(16) | _RF_RS(0), /* RELOC_16 */
77 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* RELOC_32 */
78 1.1 eeh _RF_S|_RF_A|_RF_P| _RF_SZ(8) | _RF_RS(0), /* DISP_8 */
79 1.1 eeh _RF_S|_RF_A|_RF_P| _RF_SZ(16) | _RF_RS(0), /* DISP_16 */
80 1.1 eeh _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(0), /* DISP_32 */
81 1.1 eeh _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(2), /* WDISP_30 */
82 1.1 eeh _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(2), /* WDISP_22 */
83 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(10), /* HI22 */
84 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* 22 */
85 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* 13 */
86 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* LO10 */
87 1.1 eeh _RF_G| _RF_SZ(32) | _RF_RS(0), /* GOT10 */
88 1.1 eeh _RF_G| _RF_SZ(32) | _RF_RS(0), /* GOT13 */
89 1.1 eeh _RF_G| _RF_SZ(32) | _RF_RS(10), /* GOT22 */
90 1.1 eeh _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(0), /* PC10 */
91 1.1 eeh _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(10), /* PC22 */
92 1.1 eeh _RF_A|_RF_P| _RF_SZ(32) | _RF_RS(2), /* WPLT30 */
93 1.1 eeh _RF_SZ(32) | _RF_RS(0), /* COPY */
94 1.1 eeh _RF_S|_RF_A| _RF_SZ(64) | _RF_RS(0), /* GLOB_DAT */
95 1.1 eeh _RF_SZ(32) | _RF_RS(0), /* JMP_SLOT */
96 1.1 eeh _RF_A| _RF_B| _RF_SZ(64) | _RF_RS(0), /* RELATIVE */
97 1.2 eeh _RF_S|_RF_A| _RF_U| _RF_SZ(32) | _RF_RS(0), /* UA_32 */
98 1.1 eeh
99 1.1 eeh _RF_A| _RF_SZ(32) | _RF_RS(0), /* PLT32 */
100 1.1 eeh _RF_A| _RF_SZ(32) | _RF_RS(10), /* HIPLT22 */
101 1.1 eeh _RF_A| _RF_SZ(32) | _RF_RS(0), /* LOPLT10 */
102 1.1 eeh _RF_A|_RF_P| _RF_SZ(32) | _RF_RS(0), /* PCPLT32 */
103 1.1 eeh _RF_A|_RF_P| _RF_SZ(32) | _RF_RS(10), /* PCPLT22 */
104 1.1 eeh _RF_A|_RF_P| _RF_SZ(32) | _RF_RS(0), /* PCPLT10 */
105 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* 10 */
106 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* 11 */
107 1.1 eeh _RF_S|_RF_A| _RF_SZ(64) | _RF_RS(0), /* 64 */
108 1.1 eeh _RF_S|_RF_A|/*extra*/ _RF_SZ(32) | _RF_RS(0), /* OLO10 */
109 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(42), /* HH22 */
110 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(32), /* HM10 */
111 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(10), /* LM22 */
112 1.1 eeh _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(42), /* PC_HH22 */
113 1.1 eeh _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(32), /* PC_HM10 */
114 1.1 eeh _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(10), /* PC_LM22 */
115 1.1 eeh _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(2), /* WDISP16 */
116 1.1 eeh _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(2), /* WDISP19 */
117 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* GLOB_JMP */
118 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* 7 */
119 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* 5 */
120 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* 6 */
121 1.1 eeh _RF_S|_RF_A|_RF_P| _RF_SZ(64) | _RF_RS(0), /* DISP64 */
122 1.1 eeh _RF_A| _RF_SZ(64) | _RF_RS(0), /* PLT64 */
123 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(10), /* HIX22 */
124 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* LOX10 */
125 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(22), /* H44 */
126 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(12), /* M44 */
127 1.1 eeh _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* L44 */
128 1.1 eeh _RF_S|_RF_A| _RF_SZ(64) | _RF_RS(0), /* REGISTER */
129 1.2 eeh _RF_S|_RF_A| _RF_U| _RF_SZ(64) | _RF_RS(0), /* UA64 */
130 1.2 eeh _RF_S|_RF_A| _RF_U| _RF_SZ(16) | _RF_RS(0), /* UA16 */
131 1.1 eeh };
132 1.1 eeh
133 1.1 eeh #ifdef RTLD_DEBUG_RELOC
134 1.1 eeh static const char *reloc_names[] = {
135 1.1 eeh "NONE", "RELOC_8", "RELOC_16", "RELOC_32", "DISP_8",
136 1.1 eeh "DISP_16", "DISP_32", "WDISP_30", "WDISP_22", "HI22",
137 1.1 eeh "22", "13", "LO10", "GOT10", "GOT13",
138 1.1 eeh "GOT22", "PC10", "PC22", "WPLT30", "COPY",
139 1.1 eeh "GLOB_DAT", "JMP_SLOT", "RELATIVE", "UA_32", "PLT32",
140 1.1 eeh "HIPLT22", "LOPLT10", "LOPLT10", "PCPLT22", "PCPLT32",
141 1.1 eeh "10", "11", "64", "OLO10", "HH22",
142 1.1 eeh "HM10", "LM22", "PC_HH22", "PC_HM10", "PC_LM22",
143 1.1 eeh "WDISP16", "WDISP19", "GLOB_JMP", "7", "5", "6",
144 1.1 eeh "DISP64", "PLT64", "HIX22", "LOX10", "H44", "M44",
145 1.1 eeh "L44", "REGISTER", "UA64", "UA16"
146 1.1 eeh };
147 1.1 eeh #endif
148 1.1 eeh
149 1.1 eeh #define RELOC_RESOLVE_SYMBOL(t) ((reloc_target_flags[t] & _RF_S) != 0)
150 1.1 eeh #define RELOC_PC_RELATIVE(t) ((reloc_target_flags[t] & _RF_P) != 0)
151 1.1 eeh #define RELOC_BASE_RELATIVE(t) ((reloc_target_flags[t] & _RF_B) != 0)
152 1.2 eeh #define RELOC_UNALIGNED(t) ((reloc_target_flags[t] & _RF_U) != 0)
153 1.2 eeh #define RELOC_USE_ADDEND(t) ((reloc_target_flags[t] & _RF_A) != 0)
154 1.1 eeh #define RELOC_TARGET_SIZE(t) ((reloc_target_flags[t] >> 8) & 0xff)
155 1.1 eeh #define RELOC_VALUE_RIGHTSHIFT(t) (reloc_target_flags[t] & 0xff)
156 1.1 eeh
157 1.1 eeh static long reloc_target_bitmask[] = {
158 1.1 eeh #define _BM(x) (~(-(1ULL << (x))))
159 1.1 eeh 0, /* NONE */
160 1.1 eeh _BM(8), _BM(16), _BM(32), /* RELOC_8, _16, _32 */
161 1.1 eeh _BM(8), _BM(16), _BM(32), /* DISP8, DISP16, DISP32 */
162 1.1 eeh _BM(30), _BM(22), /* WDISP30, WDISP22 */
163 1.1 eeh _BM(22), _BM(22), /* HI22, _22 */
164 1.1 eeh _BM(13), _BM(10), /* RELOC_13, _LO10 */
165 1.1 eeh _BM(10), _BM(13), _BM(22), /* GOT10, GOT13, GOT22 */
166 1.1 eeh _BM(10), _BM(22), /* _PC10, _PC22 */
167 1.1 eeh _BM(30), 0, /* _WPLT30, _COPY */
168 1.1 eeh _BM(32), _BM(32), _BM(32), /* _GLOB_DAT, JMP_SLOT, _RELATIVE */
169 1.1 eeh _BM(32), _BM(32), /* _UA32, PLT32 */
170 1.1 eeh _BM(22), _BM(10), /* _HIPLT22, LOPLT10 */
171 1.1 eeh _BM(32), _BM(22), _BM(10), /* _PCPLT32, _PCPLT22, _PCPLT10 */
172 1.1 eeh _BM(10), _BM(11), -1, /* _10, _11, _64 */
173 1.1 eeh _BM(10), _BM(22), /* _OLO10, _HH22 */
174 1.1 eeh _BM(10), _BM(22), /* _HM10, _LM22 */
175 1.1 eeh _BM(22), _BM(10), _BM(22), /* _PC_HH22, _PC_HM10, _PC_LM22 */
176 1.1 eeh _BM(16), _BM(19), /* _WDISP16, _WDISP19 */
177 1.1 eeh -1, /* GLOB_JMP */
178 1.1 eeh _BM(7), _BM(5), _BM(6) /* _7, _5, _6 */
179 1.1 eeh -1, -1, /* DISP64, PLT64 */
180 1.1 eeh _BM(22), _BM(13), /* HIX22, LOX10 */
181 1.1 eeh _BM(22), _BM(10), _BM(13), /* H44, M44, L44 */
182 1.1 eeh -1, -1, _BM(16), /* REGISTER, UA64, UA16 */
183 1.1 eeh #undef _BM
184 1.1 eeh };
185 1.1 eeh #define RELOC_VALUE_BITMASK(t) (reloc_target_bitmask[t])
186 1.1 eeh
187 1.1 eeh /*
188 1.1 eeh * Instruction templates:
189 1.1 eeh */
190 1.1 eeh #define BAA 0x10400000 /* ba,a %xcc, 0 */
191 1.1 eeh #define SETHI 0x03000000 /* sethi %hi(0), %g1 */
192 1.1 eeh #define JMP 0x81c06000 /* jmpl %g1+%lo(0), %g0 */
193 1.1 eeh #define NOP 0x01000000 /* sethi %hi(0), %g0 */
194 1.1 eeh #define OR 0x82806000 /* or %g1, 0, %g1 */
195 1.1 eeh #define XOR 0x82c06000 /* xor %g1, 0, %g1 */
196 1.1 eeh #define MOV71 0x8283a000 /* or %o7, 0, %g1 */
197 1.1 eeh #define MOV17 0x9c806000 /* or %g1, 0, %o7 */
198 1.1 eeh #define CALL 0x40000000 /* call 0 */
199 1.1 eeh #define SLLX 0x8b407000 /* sllx %g1, 0, %g1 */
200 1.1 eeh #define SETHIG5 0x0b000000 /* sethi %hi(0), %g5 */
201 1.1 eeh #define ORG5 0x82804005 /* or %g1, %g5, %g1 */
202 1.1 eeh
203 1.1 eeh
204 1.1 eeh /* %hi(v) with variable shift */
205 1.1 eeh #define HIVAL(v, s) (((v) >> (s)) & 0x003fffff)
206 1.1 eeh #define LOVAL(v) ((v) & 0x000003ff)
207 1.1 eeh
208 1.1 eeh int
209 1.1 eeh _rtld_relocate_plt_object(obj, rela, addrp, bind_now, dodebug)
210 1.1 eeh Obj_Entry *obj;
211 1.5 kleink const Elf_Rela *rela;
212 1.1 eeh caddr_t *addrp;
213 1.1 eeh bool bind_now;
214 1.1 eeh bool dodebug;
215 1.1 eeh {
216 1.1 eeh const Elf_Sym *def;
217 1.1 eeh const Obj_Entry *defobj;
218 1.3 mycroft Elf_Word *where = (Elf_Word *)((Elf_Addr)obj->relocbase + rela->r_offset);
219 1.1 eeh Elf_Addr value, offset;
220 1.1 eeh
221 1.1 eeh if (bind_now == 0 && obj->pltgot != NULL)
222 1.1 eeh return (0);
223 1.1 eeh
224 1.1 eeh /* Fully resolve procedure addresses now */
225 1.1 eeh
226 1.1 eeh assert(ELF_R_TYPE(rela->r_info) == R_TYPE(JMP_SLOT));
227 1.1 eeh
228 1.10 mycroft def = _rtld_find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj, true);
229 1.1 eeh if (def == NULL)
230 1.1 eeh return (-1);
231 1.1 eeh
232 1.1 eeh value = (Elf_Addr) (defobj->relocbase + def->st_value);
233 1.2 eeh rdbg(dodebug, ("bind now %d/fixup in %s --> old=%lx new=%lx",
234 1.1 eeh (int)bind_now, defobj->strtab + def->st_name,
235 1.2 eeh (u_long)*where, (u_long)value));
236 1.1 eeh
237 1.1 eeh /*
238 1.1 eeh * At the PLT entry pointed at by `where', we now construct
239 1.1 eeh * a direct transfer to the now fully resolved function
240 1.1 eeh * address.
241 1.1 eeh *
242 1.1 eeh * A PLT entry is supposed to start by looking like this:
243 1.1 eeh *
244 1.1 eeh * sethi %hi(. - .PLT0), %g1
245 1.1 eeh * ba,a %xcc, .PLT1
246 1.1 eeh * nop
247 1.1 eeh * nop
248 1.1 eeh * nop
249 1.1 eeh * nop
250 1.1 eeh * nop
251 1.1 eeh * nop
252 1.1 eeh *
253 1.1 eeh * When we replace these entries we start from the second
254 1.1 eeh * entry and do it in reverse order so the last thing we
255 1.1 eeh * do is replace the branch. That allows us to change this
256 1.1 eeh * atomically.
257 1.1 eeh *
258 1.1 eeh * We now need to find out how far we need to jump. We
259 1.1 eeh * have a choice of several different relocation techniques
260 1.1 eeh * which are increasingly expensive.
261 1.1 eeh */
262 1.1 eeh
263 1.1 eeh offset = ((Elf_Addr)where) - value;
264 1.1 eeh if (rela->r_addend) {
265 1.1 eeh Elf_Addr *ptr = (Elf_Addr *)where;
266 1.1 eeh /*
267 1.1 eeh * This entry is >32768. Just replace the pointer.
268 1.1 eeh */
269 1.1 eeh ptr[0] = value;
270 1.1 eeh
271 1.1 eeh } else if (offset <= (1L<<20) && offset >= -(1L<<20)) {
272 1.1 eeh /*
273 1.1 eeh * We're within 1MB -- we can use a direct branch insn.
274 1.1 eeh *
275 1.1 eeh * We can generate this pattern:
276 1.1 eeh *
277 1.1 eeh * sethi %hi(. - .PLT0), %g1
278 1.1 eeh * ba,a %xcc, addr
279 1.1 eeh * nop
280 1.1 eeh * nop
281 1.1 eeh * nop
282 1.1 eeh * nop
283 1.1 eeh * nop
284 1.1 eeh * nop
285 1.1 eeh *
286 1.1 eeh */
287 1.1 eeh where[1] = BAA | ((offset >> 2) &0x3fffff);
288 1.1 eeh __asm __volatile("iflush %0+4" : : "r" (where));
289 1.1 eeh } else if (value >= 0 && value < (1L<<32)) {
290 1.1 eeh /*
291 1.1 eeh * We're withing 32-bits of address zero.
292 1.1 eeh *
293 1.1 eeh * The resulting code in the jump slot is:
294 1.1 eeh *
295 1.1 eeh * sethi %hi(. - .PLT0), %g1
296 1.1 eeh * sethi %hi(addr), %g1
297 1.1 eeh * jmp %g1+%lo(addr)
298 1.1 eeh * nop
299 1.1 eeh * nop
300 1.1 eeh * nop
301 1.1 eeh * nop
302 1.1 eeh * nop
303 1.1 eeh *
304 1.1 eeh */
305 1.1 eeh where[2] = JMP | LOVAL(value);
306 1.1 eeh where[1] = SETHI | HIVAL(value, 10);
307 1.1 eeh __asm __volatile("iflush %0+8" : : "r" (where));
308 1.1 eeh __asm __volatile("iflush %0+4" : : "r" (where));
309 1.1 eeh
310 1.1 eeh } else if (value <= 0 && value > -(1L<<32)) {
311 1.1 eeh /*
312 1.1 eeh * We're withing 32-bits of address -1.
313 1.1 eeh *
314 1.1 eeh * The resulting code in the jump slot is:
315 1.1 eeh *
316 1.1 eeh * sethi %hi(. - .PLT0), %g1
317 1.1 eeh * sethi %hix(addr), %g1
318 1.1 eeh * xor %g1, %lox(addr), %g1
319 1.1 eeh * jmp %g1
320 1.1 eeh * nop
321 1.1 eeh * nop
322 1.1 eeh * nop
323 1.1 eeh * nop
324 1.1 eeh *
325 1.1 eeh */
326 1.1 eeh where[3] = JMP;
327 1.1 eeh where[2] = XOR | ((~value) & 0x00001fff);
328 1.1 eeh where[1] = SETHI | HIVAL(~value, 10);
329 1.1 eeh __asm __volatile("iflush %0+12" : : "r" (where));
330 1.1 eeh __asm __volatile("iflush %0+8" : : "r" (where));
331 1.1 eeh __asm __volatile("iflush %0+4" : : "r" (where));
332 1.1 eeh
333 1.1 eeh } else if (offset <= (1L<<32) && offset >= -((1L<<32) - 4)) {
334 1.1 eeh /*
335 1.1 eeh * We're withing 32-bits -- we can use a direct call insn
336 1.1 eeh *
337 1.1 eeh * The resulting code in the jump slot is:
338 1.1 eeh *
339 1.1 eeh * sethi %hi(. - .PLT0), %g1
340 1.1 eeh * mov %o7, %g1
341 1.1 eeh * call (.+offset)
342 1.1 eeh * mov %g1, %o7
343 1.1 eeh * nop
344 1.1 eeh * nop
345 1.1 eeh * nop
346 1.1 eeh * nop
347 1.1 eeh *
348 1.1 eeh */
349 1.1 eeh where[3] = MOV17;
350 1.1 eeh where[2] = CALL | ((offset >> 4) & 0x3fffffff);
351 1.1 eeh where[1] = MOV71;
352 1.1 eeh __asm __volatile("iflush %0+12" : : "r" (where));
353 1.1 eeh __asm __volatile("iflush %0+8" : : "r" (where));
354 1.1 eeh __asm __volatile("iflush %0+4" : : "r" (where));
355 1.1 eeh
356 1.1 eeh } else if (offset >= 0 && offset < (1L<<44)) {
357 1.1 eeh /*
358 1.1 eeh * We're withing 44 bits. We can generate this pattern:
359 1.1 eeh *
360 1.1 eeh * The resulting code in the jump slot is:
361 1.1 eeh *
362 1.1 eeh * sethi %hi(. - .PLT0), %g1
363 1.1 eeh * sethi %h44(addr), %g1
364 1.1 eeh * or %g1, %m44(addr), %g1
365 1.1 eeh * sllx %g1, 12, %g1
366 1.1 eeh * jmp %g1+%l44(addr)
367 1.1 eeh * nop
368 1.1 eeh * nop
369 1.1 eeh * nop
370 1.1 eeh *
371 1.1 eeh */
372 1.1 eeh where[4] = JMP | LOVAL(offset);
373 1.1 eeh where[3] = SLLX | 12;
374 1.1 eeh where[2] = OR | (((offset) >> 12) & 0x00001fff);
375 1.1 eeh where[1] = SETHI | HIVAL(offset, 22);
376 1.1 eeh __asm __volatile("iflush %0+16" : : "r" (where));
377 1.1 eeh __asm __volatile("iflush %0+12" : : "r" (where));
378 1.1 eeh __asm __volatile("iflush %0+8" : : "r" (where));
379 1.1 eeh __asm __volatile("iflush %0+4" : : "r" (where));
380 1.1 eeh
381 1.1 eeh } else if (offset < 0 && offset > -(1L<<44)) {
382 1.1 eeh /*
383 1.1 eeh * We're withing 44 bits. We can generate this pattern:
384 1.1 eeh *
385 1.1 eeh * The resulting code in the jump slot is:
386 1.1 eeh *
387 1.1 eeh * sethi %hi(. - .PLT0), %g1
388 1.1 eeh * sethi %h44(-addr), %g1
389 1.1 eeh * xor %g1, %m44(-addr), %g1
390 1.1 eeh * sllx %g1, 12, %g1
391 1.1 eeh * jmp %g1+%l44(addr)
392 1.1 eeh * nop
393 1.1 eeh * nop
394 1.1 eeh * nop
395 1.1 eeh *
396 1.1 eeh */
397 1.1 eeh where[4] = JMP | LOVAL(offset);
398 1.1 eeh where[3] = SLLX | 12;
399 1.1 eeh where[2] = XOR | (((~offset) >> 12) & 0x00001fff);
400 1.1 eeh where[1] = SETHI | HIVAL(~offset, 22);
401 1.1 eeh __asm __volatile("iflush %0+16" : : "r" (where));
402 1.1 eeh __asm __volatile("iflush %0+12" : : "r" (where));
403 1.1 eeh __asm __volatile("iflush %0+8" : : "r" (where));
404 1.1 eeh __asm __volatile("iflush %0+4" : : "r" (where));
405 1.1 eeh
406 1.1 eeh } else {
407 1.1 eeh /*
408 1.1 eeh * We need to load all 64-bits
409 1.1 eeh *
410 1.1 eeh * The resulting code in the jump slot is:
411 1.1 eeh *
412 1.1 eeh * sethi %hi(. - .PLT0), %g1
413 1.1 eeh * sethi %hh(addr), %g1
414 1.1 eeh * sethi %lm(addr), %g5
415 1.1 eeh * or %g1, %hm(addr), %g1
416 1.1 eeh * sllx %g1, 32, %g1
417 1.1 eeh * or %g1, %g5, %g1
418 1.1 eeh * jmp %g1+%lo(addr)
419 1.1 eeh * nop
420 1.1 eeh *
421 1.1 eeh */
422 1.1 eeh where[6] = JMP | LOVAL(value);
423 1.1 eeh where[5] = ORG5;
424 1.1 eeh where[4] = SLLX | 12;
425 1.1 eeh where[3] = OR | LOVAL((value) >> 32);
426 1.1 eeh where[2] = SETHIG5 | HIVAL(value, 10);
427 1.1 eeh where[1] = SETHI | HIVAL(value, 42);
428 1.1 eeh __asm __volatile("iflush %0+20" : : "r" (where));
429 1.1 eeh __asm __volatile("iflush %0+16" : : "r" (where));
430 1.1 eeh __asm __volatile("iflush %0+16" : : "r" (where));
431 1.1 eeh __asm __volatile("iflush %0+12" : : "r" (where));
432 1.1 eeh __asm __volatile("iflush %0+8" : : "r" (where));
433 1.1 eeh __asm __volatile("iflush %0+4" : : "r" (where));
434 1.1 eeh
435 1.1 eeh }
436 1.1 eeh
437 1.1 eeh if (addrp != NULL)
438 1.1 eeh *addrp = (caddr_t)value;
439 1.1 eeh
440 1.1 eeh return (0);
441 1.1 eeh }
442 1.1 eeh
443 1.1 eeh /*
444 1.1 eeh * Install rtld function call into this PLT slot.
445 1.1 eeh */
446 1.1 eeh #define SAVE 0x9de3bf50
447 1.1 eeh #define SETHI_l0 0x21000000
448 1.1 eeh #define SETHI_l1 0x23000000
449 1.1 eeh #define OR_l0_l0 0xa0142000
450 1.1 eeh #define SLLX_l0_32_l0 0xa12c3020
451 1.1 eeh #define OR_l0_l1_l0 0xa0140011
452 1.4 eeh #define JMPL_l0_o1 0x93c42000
453 1.1 eeh #define MOV_g1_o0 0x90100001
454 1.1 eeh
455 1.3 mycroft void _rtld_install_plt __P((Elf_Word *pltgot, Elf_Addr proc));
456 1.1 eeh
457 1.1 eeh void
458 1.1 eeh _rtld_install_plt(pltgot, proc)
459 1.3 mycroft Elf_Word *pltgot;
460 1.1 eeh Elf_Addr proc;
461 1.1 eeh {
462 1.1 eeh pltgot[0] = SAVE;
463 1.1 eeh pltgot[1] = SETHI_l0 | HIVAL(proc, 42);
464 1.1 eeh pltgot[2] = SETHI_l1 | HIVAL(proc, 10);
465 1.1 eeh pltgot[3] = OR_l0_l0 | LOVAL((proc) >> 32);
466 1.1 eeh pltgot[4] = SLLX_l0_32_l0;
467 1.1 eeh pltgot[5] = OR_l0_l1_l0;
468 1.4 eeh pltgot[6] = JMPL_l0_o1 | LOVAL(proc);
469 1.1 eeh pltgot[7] = MOV_g1_o0;
470 1.1 eeh }
471 1.2 eeh
472 1.2 eeh long _rtld_bind_start_0_stub __P((long x, long y));
473 1.2 eeh long
474 1.2 eeh _rtld_bind_start_0_stub(x, y)
475 1.2 eeh long x, y;
476 1.2 eeh {
477 1.2 eeh long i;
478 1.2 eeh long n;
479 1.2 eeh
480 1.2 eeh i = x - y + 1048596;
481 1.2 eeh n = 32768 + (i/5120)*160 + (i%5120)/24;
482 1.2 eeh
483 1.2 eeh return (n);
484 1.2 eeh }
485 1.2 eeh
486 1.6 mycroft void
487 1.6 mycroft _rtld_setup_pltgot(const Obj_Entry *obj)
488 1.6 mycroft {
489 1.6 mycroft /*
490 1.6 mycroft * On sparc64 we got troubles.
491 1.6 mycroft *
492 1.6 mycroft * Instructions are 4 bytes long.
493 1.6 mycroft * Elf[64]_Addr is 8 bytes long, so are our pltglot[]
494 1.6 mycroft * array entries.
495 1.6 mycroft * Each PLT entry jumps to PLT0 to enter the dynamic
496 1.6 mycroft * linker.
497 1.6 mycroft * Loading an arbitrary 64-bit pointer takes 6
498 1.6 mycroft * instructions and 2 registers.
499 1.6 mycroft *
500 1.6 mycroft * Somehow we need to issue a save to get a new stack
501 1.6 mycroft * frame, load the address of the dynamic linker, and
502 1.6 mycroft * jump there, in 8 instructions or less.
503 1.6 mycroft *
504 1.6 mycroft * Oh, we need to fill out both PLT0 and PLT1.
505 1.6 mycroft */
506 1.6 mycroft {
507 1.6 mycroft Elf_Word *entry = (Elf_Word *)obj->pltgot;
508 1.6 mycroft extern void _rtld_bind_start_0 __P((long, long));
509 1.6 mycroft extern void _rtld_bind_start_1 __P((long, long));
510 1.6 mycroft
511 1.6 mycroft /* Install in entries 0 and 1 */
512 1.6 mycroft _rtld_install_plt(&entry[0], (Elf_Addr) &_rtld_bind_start_0);
513 1.6 mycroft _rtld_install_plt(&entry[8], (Elf_Addr) &_rtld_bind_start_1);
514 1.6 mycroft
515 1.6 mycroft /*
516 1.6 mycroft * Install the object reference in first slot
517 1.6 mycroft * of entry 2.
518 1.6 mycroft */
519 1.6 mycroft obj->pltgot[8] = (Elf_Addr) obj;
520 1.6 mycroft }
521 1.8 mycroft }
522 1.8 mycroft
523 1.8 mycroft int
524 1.9 mycroft _rtld_relocate_nonplt_objects(obj, dodebug)
525 1.8 mycroft Obj_Entry *obj;
526 1.8 mycroft bool dodebug;
527 1.8 mycroft {
528 1.9 mycroft const Elf_Rela *rela;
529 1.8 mycroft
530 1.9 mycroft for (rela = obj->rela; rela < obj->relalim; rela++) {
531 1.9 mycroft Elf_Addr *where;
532 1.9 mycroft Elf_Word type;
533 1.9 mycroft Elf_Addr value = 0, mask;
534 1.9 mycroft const Elf_Sym *def = NULL;
535 1.9 mycroft const Obj_Entry *defobj = NULL;
536 1.10 mycroft unsigned long symnum;
537 1.9 mycroft
538 1.9 mycroft where = (Elf_Addr *) (obj->relocbase + rela->r_offset);
539 1.10 mycroft symnum = ELF_R_SYM(rela->r_info);
540 1.9 mycroft
541 1.9 mycroft type = ELF_R_TYPE(rela->r_info);
542 1.9 mycroft if (type == R_TYPE(NONE))
543 1.9 mycroft return (0);
544 1.9 mycroft
545 1.9 mycroft /* We do JMP_SLOTs in relocate_plt_object() below */
546 1.9 mycroft if (type == R_TYPE(JMP_SLOT))
547 1.9 mycroft return (0);
548 1.9 mycroft
549 1.9 mycroft /* COPY relocs are also handled elsewhere */
550 1.9 mycroft if (type == R_TYPE(COPY))
551 1.9 mycroft return (0);
552 1.8 mycroft
553 1.9 mycroft /*
554 1.9 mycroft * We use the fact that relocation types are an `enum'
555 1.9 mycroft * Note: R_SPARC_UA16 is currently numerically largest.
556 1.9 mycroft */
557 1.9 mycroft if (type > R_TYPE(UA16))
558 1.9 mycroft return (-1);
559 1.8 mycroft
560 1.9 mycroft value = rela->r_addend;
561 1.8 mycroft
562 1.9 mycroft /*
563 1.9 mycroft * Handle relative relocs here, because we might not
564 1.9 mycroft * be able to access globals yet.
565 1.9 mycroft */
566 1.9 mycroft if (!dodebug && type == R_TYPE(RELATIVE)) {
567 1.9 mycroft /* XXXX -- apparently we ignore the preexisting value */
568 1.9 mycroft *where = (Elf_Addr)(obj->relocbase + value);
569 1.9 mycroft return (0);
570 1.9 mycroft }
571 1.8 mycroft
572 1.9 mycroft if (RELOC_RESOLVE_SYMBOL(type)) {
573 1.8 mycroft
574 1.9 mycroft /* Find the symbol */
575 1.10 mycroft def = _rtld_find_symdef(symnum, obj, &defobj, false);
576 1.9 mycroft if (def == NULL)
577 1.9 mycroft return (-1);
578 1.8 mycroft
579 1.9 mycroft /* Add in the symbol's absolute address */
580 1.9 mycroft value += (Elf_Addr)(defobj->relocbase + def->st_value);
581 1.9 mycroft }
582 1.8 mycroft
583 1.9 mycroft if (RELOC_PC_RELATIVE(type)) {
584 1.9 mycroft value -= (Elf_Addr)where;
585 1.9 mycroft }
586 1.8 mycroft
587 1.9 mycroft if (RELOC_BASE_RELATIVE(type)) {
588 1.9 mycroft /*
589 1.9 mycroft * Note that even though sparcs use `Elf_rela'
590 1.9 mycroft * exclusively we still need the implicit memory addend
591 1.9 mycroft * in relocations referring to GOT entries.
592 1.9 mycroft * Undoubtedly, someone f*cked this up in the distant
593 1.9 mycroft * past, and now we're stuck with it in the name of
594 1.9 mycroft * compatibility for all eternity..
595 1.9 mycroft *
596 1.9 mycroft * In any case, the implicit and explicit should be
597 1.9 mycroft * mutually exclusive. We provide a check for that
598 1.9 mycroft * here.
599 1.9 mycroft */
600 1.8 mycroft #ifdef DIAGNOSTIC
601 1.9 mycroft if (value != 0 && *where != 0) {
602 1.9 mycroft xprintf("BASE_REL(%s): where=%p, *where 0x%lx, "
603 1.9 mycroft "addend=0x%lx, base %p\n",
604 1.9 mycroft obj->path, where, *where,
605 1.9 mycroft rela->r_addend, obj->relocbase);
606 1.9 mycroft }
607 1.9 mycroft #endif
608 1.9 mycroft /* XXXX -- apparently we ignore the preexisting value */
609 1.9 mycroft value += (Elf_Addr)(obj->relocbase);
610 1.8 mycroft }
611 1.8 mycroft
612 1.9 mycroft mask = RELOC_VALUE_BITMASK(type);
613 1.9 mycroft value >>= RELOC_VALUE_RIGHTSHIFT(type);
614 1.9 mycroft value &= mask;
615 1.9 mycroft
616 1.9 mycroft if (RELOC_UNALIGNED(type)) {
617 1.9 mycroft /* Handle unaligned relocations. */
618 1.9 mycroft Elf_Addr tmp = 0;
619 1.9 mycroft char *ptr = (char *)where;
620 1.9 mycroft int i, size = RELOC_TARGET_SIZE(type)/8;
621 1.9 mycroft
622 1.9 mycroft /* Read it in one byte at a time. */
623 1.9 mycroft for (i=0; i<size; i++)
624 1.9 mycroft tmp = (tmp << 8) | ptr[i];
625 1.9 mycroft
626 1.9 mycroft tmp &= ~mask;
627 1.9 mycroft tmp |= value;
628 1.9 mycroft
629 1.9 mycroft /* Write it back out. */
630 1.9 mycroft for (i=0; i<size; i++)
631 1.9 mycroft ptr[i] = ((tmp >> (8*i)) & 0xff);
632 1.8 mycroft #ifdef RTLD_DEBUG_RELOC
633 1.9 mycroft value = (Elf_Addr)tmp;
634 1.8 mycroft #endif
635 1.8 mycroft
636 1.9 mycroft } else if (RELOC_TARGET_SIZE(type) > 32) {
637 1.9 mycroft *where &= ~mask;
638 1.9 mycroft *where |= value;
639 1.8 mycroft #ifdef RTLD_DEBUG_RELOC
640 1.9 mycroft value = (Elf_Addr)*where;
641 1.8 mycroft #endif
642 1.9 mycroft } else {
643 1.9 mycroft Elf32_Addr *where32 = (Elf32_Addr *)where;
644 1.8 mycroft
645 1.9 mycroft *where32 &= ~mask;
646 1.9 mycroft *where32 |= value;
647 1.8 mycroft #ifdef RTLD_DEBUG_RELOC
648 1.9 mycroft value = (Elf_Addr)*where32;
649 1.8 mycroft #endif
650 1.9 mycroft }
651 1.8 mycroft
652 1.8 mycroft #ifdef RTLD_DEBUG_RELOC
653 1.9 mycroft if (RELOC_RESOLVE_SYMBOL(type)) {
654 1.9 mycroft rdbg(dodebug, ("%s %s in %s --> %p %s",
655 1.9 mycroft reloc_names[type],
656 1.9 mycroft defobj->strtab + def->st_name, obj->path,
657 1.9 mycroft (void *)value, defobj->path));
658 1.9 mycroft }
659 1.9 mycroft else {
660 1.9 mycroft rdbg(dodebug, ("%s --> %p", reloc_names[type],
661 1.9 mycroft (void *)value));
662 1.9 mycroft }
663 1.9 mycroft #endif
664 1.8 mycroft }
665 1.8 mycroft return (0);
666 1.6 mycroft }
667