xref: /trueos/libexec/rtld-elf/sparc64/reloc.c (revision 7a1ab70b9590c4c122be3d913b579be45424f95a) 
1 /*	$NetBSD: mdreloc.c,v 1.42 2008/04/28 20:23:04 martin Exp $	*/
2 
3 /*-
4  * Copyright (c) 2000 Eduardo Horvath.
5  * Copyright (c) 1999 The NetBSD Foundation, Inc.
6  * All rights reserved.
7  *
8  * This code is derived from software contributed to The NetBSD Foundation
9  * by Paul Kranenburg.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 #include <sys/param.h>
37 #include <sys/mman.h>
38 
39 #include <errno.h>
40 #include <stdio.h>
41 #include <stdlib.h>
42 #include <string.h>
43 #include <unistd.h>
44 
45 #include "debug.h"
46 #include "rtld.h"
47 
48 /*
49  * The following table holds for each relocation type:
50  *	- the width in bits of the memory location the relocation
51  *	  applies to (not currently used)
52  *	- the number of bits the relocation value must be shifted to the
53  *	  right (i.e. discard least significant bits) to fit into
54  *	  the appropriate field in the instruction word.
55  *	- flags indicating whether
56  *		* the relocation involves a symbol
57  *		* the relocation is relative to the current position
58  *		* the relocation is for a GOT entry
59  *		* the relocation is relative to the load address
60  *
61  */
62 #define	_RF_S		0x80000000		/* Resolve symbol */
63 #define	_RF_A		0x40000000		/* Use addend */
64 #define	_RF_P		0x20000000		/* Location relative */
65 #define	_RF_G		0x10000000		/* GOT offset */
66 #define	_RF_B		0x08000000		/* Load address relative */
67 #define	_RF_U		0x04000000		/* Unaligned */
68 #define	_RF_X		0x02000000		/* Bare symbols, needs proc */
69 #define	_RF_D		0x01000000		/* Use dynamic TLS offset */
70 #define	_RF_O		0x00800000		/* Use static TLS offset */
71 #define	_RF_I		0x00400000		/* Use TLS object ID */
72 #define	_RF_SZ(s)	(((s) & 0xff) << 8)	/* memory target size */
73 #define	_RF_RS(s)	( (s) & 0xff)		/* right shift */
74 static const int reloc_target_flags[] = {
75 	0,							/* NONE */
76 	_RF_S|_RF_A|		_RF_SZ(8)  | _RF_RS(0),		/* 8 */
77 	_RF_S|_RF_A|		_RF_SZ(16) | _RF_RS(0),		/* 16 */
78 	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(0),		/* 32 */
79 	_RF_S|_RF_A|_RF_P|	_RF_SZ(8)  | _RF_RS(0),		/* DISP_8 */
80 	_RF_S|_RF_A|_RF_P|	_RF_SZ(16) | _RF_RS(0),		/* DISP_16 */
81 	_RF_S|_RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(0),		/* DISP_32 */
82 	_RF_S|_RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(2),		/* WDISP_30 */
83 	_RF_S|_RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(2),		/* WDISP_22 */
84 	_RF_S|_RF_A|_RF_X|	_RF_SZ(32) | _RF_RS(10),	/* HI22 */
85 	_RF_S|_RF_A|_RF_X|	_RF_SZ(32) | _RF_RS(0),		/* 22 */
86 	_RF_S|_RF_A|_RF_X|	_RF_SZ(32) | _RF_RS(0),		/* 13 */
87 	_RF_S|_RF_A|_RF_X|	_RF_SZ(32) | _RF_RS(0),		/* LO10 */
88 	_RF_G|			_RF_SZ(32) | _RF_RS(0),		/* GOT10 */
89 	_RF_G|			_RF_SZ(32) | _RF_RS(0),		/* GOT13 */
90 	_RF_G|			_RF_SZ(32) | _RF_RS(10),	/* GOT22 */
91 	_RF_S|_RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(0),		/* PC10 */
92 	_RF_S|_RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(10),	/* PC22 */
93 	      _RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(2),		/* WPLT30 */
94 				_RF_SZ(32) | _RF_RS(0),		/* COPY */
95 	_RF_S|_RF_A|		_RF_SZ(64) | _RF_RS(0),		/* GLOB_DAT */
96 				_RF_SZ(32) | _RF_RS(0),		/* JMP_SLOT */
97 	      _RF_A|	_RF_B|	_RF_SZ(64) | _RF_RS(0),		/* RELATIVE */
98 	_RF_S|_RF_A|	_RF_U|	_RF_SZ(32) | _RF_RS(0),		/* UA_32 */
99 
100 	      _RF_A|		_RF_SZ(32) | _RF_RS(0),		/* PLT32 */
101 	      _RF_A|		_RF_SZ(32) | _RF_RS(10),	/* HIPLT22 */
102 	      _RF_A|		_RF_SZ(32) | _RF_RS(0),		/* LOPLT10 */
103 	      _RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(0),		/* PCPLT32 */
104 	      _RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(10),	/* PCPLT22 */
105 	      _RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(0),		/* PCPLT10 */
106 	_RF_S|_RF_A|_RF_X|	_RF_SZ(32) | _RF_RS(0),		/* 10 */
107 	_RF_S|_RF_A|_RF_X|	_RF_SZ(32) | _RF_RS(0),		/* 11 */
108 	_RF_S|_RF_A|_RF_X|	_RF_SZ(64) | _RF_RS(0),		/* 64 */
109 	_RF_S|_RF_A|/*extra*/	_RF_SZ(32) | _RF_RS(0),		/* OLO10 */
110 	_RF_S|_RF_A|_RF_X|	_RF_SZ(32) | _RF_RS(42),	/* HH22 */
111 	_RF_S|_RF_A|_RF_X|	_RF_SZ(32) | _RF_RS(32),	/* HM10 */
112 	_RF_S|_RF_A|_RF_X|	_RF_SZ(32) | _RF_RS(10),	/* LM22 */
113 	_RF_S|_RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(42),	/* PC_HH22 */
114 	_RF_S|_RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(32),	/* PC_HM10 */
115 	_RF_S|_RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(10),	/* PC_LM22 */
116 	_RF_S|_RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(2),		/* WDISP16 */
117 	_RF_S|_RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(2),		/* WDISP19 */
118 	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(0),		/* GLOB_JMP */
119 	_RF_S|_RF_A|_RF_X|	_RF_SZ(32) | _RF_RS(0),		/* 7 */
120 	_RF_S|_RF_A|_RF_X|	_RF_SZ(32) | _RF_RS(0),		/* 5 */
121 	_RF_S|_RF_A|_RF_X|	_RF_SZ(32) | _RF_RS(0),		/* 6 */
122 	_RF_S|_RF_A|_RF_P|	_RF_SZ(64) | _RF_RS(0),		/* DISP64 */
123 	      _RF_A|		_RF_SZ(64) | _RF_RS(0),		/* PLT64 */
124 	_RF_S|_RF_A|_RF_X|	_RF_SZ(32) | _RF_RS(10),	/* HIX22 */
125 	_RF_S|_RF_A|_RF_X|	_RF_SZ(32) | _RF_RS(0),		/* LOX10 */
126 	_RF_S|_RF_A|_RF_X|	_RF_SZ(32) | _RF_RS(22),	/* H44 */
127 	_RF_S|_RF_A|_RF_X|	_RF_SZ(32) | _RF_RS(12),	/* M44 */
128 	_RF_S|_RF_A|_RF_X|	_RF_SZ(32) | _RF_RS(0),		/* L44 */
129 	_RF_S|_RF_A|		_RF_SZ(64) | _RF_RS(0),		/* REGISTER */
130 	_RF_S|_RF_A|	_RF_U|	_RF_SZ(64) | _RF_RS(0),		/* UA64 */
131 	_RF_S|_RF_A|	_RF_U|	_RF_SZ(16) | _RF_RS(0),		/* UA16 */
132 
133 	/* TLS */
134 	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(10),	/* GD_HI22 */
135 	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(0),		/* GD_LO10 */
136 	0,							/* GD_ADD */
137 	      _RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(2),		/* GD_CALL */
138 	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(10),	/* LDM_HI22 */
139 	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(0),		/* LDM_LO10 */
140 	0,							/* LDM_ADD */
141 	      _RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(2),		/* LDM_CALL */
142 	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(10),	/* LDO_HIX22 */
143 	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(0),		/* LDO_LOX10 */
144 	0,							/* LDO_ADD */
145 	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(10),	/* IE_HI22 */
146 	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(0),		/* IE_LO10 */
147 	0,							/* IE_LD */
148 	0,							/* IE_LDX */
149 	0,							/* IE_ADD */
150 	_RF_S|_RF_A|	_RF_O|	_RF_SZ(32) | _RF_RS(10),	/* LE_HIX22 */
151 	_RF_S|_RF_A|	_RF_O|	_RF_SZ(32) | _RF_RS(0),		/* LE_LOX10 */
152 	_RF_S|		_RF_I|	_RF_SZ(32) | _RF_RS(0),		/* DTPMOD32 */
153 	_RF_S|		_RF_I|	_RF_SZ(64) | _RF_RS(0),		/* DTPMOD64 */
154 	_RF_S|_RF_A|	_RF_D|	_RF_SZ(32) | _RF_RS(0),		/* DTPOFF32 */
155 	_RF_S|_RF_A|	_RF_D|	_RF_SZ(64) | _RF_RS(0),		/* DTPOFF64 */
156 	_RF_S|_RF_A|	_RF_O|	_RF_SZ(32) | _RF_RS(0),		/* TPOFF32 */
157 	_RF_S|_RF_A|	_RF_O|	_RF_SZ(64) | _RF_RS(0)		/* TPOFF64 */
158 };
159 
160 #if 0
161 static const char *const reloc_names[] = {
162 	"NONE", "8", "16", "32", "DISP_8", "DISP_16", "DISP_32", "WDISP_30",
163 	"WDISP_22", "HI22", "22", "13", "LO10", "GOT10", "GOT13", "GOT22",
164 	"PC10", "PC22", "WPLT30", "COPY", "GLOB_DAT", "JMP_SLOT", "RELATIVE",
165 	"UA_32", "PLT32", "HIPLT22", "LOPLT10", "LOPLT10", "PCPLT22",
166 	"PCPLT32", "10", "11", "64", "OLO10", "HH22", "HM10", "LM22",
167 	"PC_HH22", "PC_HM10", "PC_LM22", "WDISP16", "WDISP19", "GLOB_JMP",
168 	"7", "5", "6", "DISP64", "PLT64", "HIX22", "LOX10", "H44", "M44",
169 	"L44", "REGISTER", "UA64", "UA16", "GD_HI22", "GD_LO10", "GD_ADD",
170 	"GD_CALL", "LDM_HI22", "LDMO10", "LDM_ADD", "LDM_CALL", "LDO_HIX22",
171 	"LDO_LOX10", "LDO_ADD", "IE_HI22", "IE_LO10", "IE_LD", "IE_LDX",
172 	"IE_ADD", "LE_HIX22", "LE_LOX10", "DTPMOD32", "DTPMOD64", "DTPOFF32",
173 	"DTPOFF64", "TPOFF32", "TPOFF64"
174 };
175 #endif
176 
177 #define	RELOC_RESOLVE_SYMBOL(t)		((reloc_target_flags[t] & _RF_S) != 0)
178 #define	RELOC_PC_RELATIVE(t)		((reloc_target_flags[t] & _RF_P) != 0)
179 #define	RELOC_BASE_RELATIVE(t)		((reloc_target_flags[t] & _RF_B) != 0)
180 #define	RELOC_UNALIGNED(t)		((reloc_target_flags[t] & _RF_U) != 0)
181 #define	RELOC_USE_ADDEND(t)		((reloc_target_flags[t] & _RF_A) != 0)
182 #define	RELOC_BARE_SYMBOL(t)		((reloc_target_flags[t] & _RF_X) != 0)
183 #define	RELOC_USE_TLS_DOFF(t)		((reloc_target_flags[t] & _RF_D) != 0)
184 #define	RELOC_USE_TLS_OFF(t)		((reloc_target_flags[t] & _RF_O) != 0)
185 #define	RELOC_USE_TLS_ID(t)		((reloc_target_flags[t] & _RF_I) != 0)
186 #define	RELOC_TARGET_SIZE(t)		((reloc_target_flags[t] >> 8) & 0xff)
187 #define	RELOC_VALUE_RIGHTSHIFT(t)	(reloc_target_flags[t] & 0xff)
188 
189 static const long reloc_target_bitmask[] = {
190 #define	_BM(x)	(~(-(1ULL << (x))))
191 	0,				/* NONE */
192 	_BM(8), _BM(16), _BM(32),	/* 8, 16, 32 */
193 	_BM(8), _BM(16), _BM(32),	/* DISP8, DISP16, DISP32 */
194 	_BM(30), _BM(22),		/* WDISP30, WDISP22 */
195 	_BM(22), _BM(22),		/* HI22, 22 */
196 	_BM(13), _BM(10),		/* 13, LO10 */
197 	_BM(10), _BM(13), _BM(22),	/* GOT10, GOT13, GOT22 */
198 	_BM(10), _BM(22),		/* PC10, PC22 */
199 	_BM(30), 0,			/* WPLT30, COPY */
200 	_BM(32), _BM(32), _BM(32),	/* GLOB_DAT, JMP_SLOT, RELATIVE */
201 	_BM(32), _BM(32),		/* UA32, PLT32 */
202 	_BM(22), _BM(10),		/* HIPLT22, LOPLT10 */
203 	_BM(32), _BM(22), _BM(10),	/* PCPLT32, PCPLT22, PCPLT10 */
204 	_BM(10), _BM(11), -1,		/* 10, 11, 64 */
205 	_BM(13), _BM(22),		/* OLO10, HH22 */
206 	_BM(10), _BM(22),		/* HM10, LM22 */
207 	_BM(22), _BM(10), _BM(22),	/* PC_HH22, PC_HM10, PC_LM22 */
208 	_BM(16), _BM(19),		/* WDISP16, WDISP19 */
209 	-1,				/* GLOB_JMP */
210 	_BM(7), _BM(5), _BM(6),		/* 7, 5, 6 */
211 	-1, -1,				/* DISP64, PLT64 */
212 	_BM(22), _BM(13),		/* HIX22, LOX10 */
213 	_BM(22), _BM(10), _BM(13),	/* H44, M44, L44 */
214 	-1, -1, _BM(16),		/* REGISTER, UA64, UA16 */
215 	_BM(22), _BM(10), 0, _BM(30),	/* GD_HI22, GD_LO10, GD_ADD, GD_CALL */
216 	_BM(22), _BM(10), 0,		/* LDM_HI22, LDMO10, LDM_ADD */
217 	_BM(30),			/* LDM_CALL */
218 	_BM(22), _BM(10), 0,		/* LDO_HIX22, LDO_LOX10, LDO_ADD */
219 	_BM(22), _BM(10), 0, 0,		/* IE_HI22, IE_LO10, IE_LD, IE_LDX */
220 	0,				/* IE_ADD */
221 	_BM(22), _BM(13),		/* LE_HIX22, LE_LOX10 */
222 	_BM(32), -1,			/* DTPMOD32, DTPMOD64 */
223 	_BM(32), -1,			/* DTPOFF32, DTPOFF64 */
224 	_BM(32), -1			/* TPOFF32, TPOFF64 */
225 #undef _BM
226 };
227 #define	RELOC_VALUE_BITMASK(t)	(reloc_target_bitmask[t])
228 
229 #undef flush
230 #define	flush(va, offs)							\
231 	__asm __volatile("flush %0 + %1" : : "r" (va), "I" (offs));
232 
233 static int reloc_nonplt_object(Obj_Entry *obj, const Elf_Rela *rela,
234     SymCache *cache, int flags, RtldLockState *lockstate);
235 static void install_plt(Elf_Word *pltgot, Elf_Addr proc);
236 
237 extern char _rtld_bind_start_0[];
238 extern char _rtld_bind_start_1[];
239 
240 int
do_copy_relocations(Obj_Entry * dstobj)241 do_copy_relocations(Obj_Entry *dstobj)
242 {
243 	const Elf_Rela *relalim;
244 	const Elf_Rela *rela;
245 	const Elf_Sym *dstsym;
246 	const Elf_Sym *srcsym;
247 	void *dstaddr;
248 	const void *srcaddr;
249 	const Obj_Entry *srcobj, *defobj;
250 	SymLook req;
251 	const char *name;
252 	size_t size;
253 	int res;
254 
255 	assert(dstobj->mainprog);   /* COPY relocations are invalid elsewhere */
256 
257 	relalim = (const Elf_Rela *)((caddr_t)dstobj->rela + dstobj->relasize);
258 	for (rela = dstobj->rela; rela < relalim; rela++) {
259 		if (ELF_R_TYPE(rela->r_info) == R_SPARC_COPY) {
260 			dstaddr = (void *)(dstobj->relocbase + rela->r_offset);
261 			dstsym = dstobj->symtab + ELF_R_SYM(rela->r_info);
262 			name = dstobj->strtab + dstsym->st_name;
263 			size = dstsym->st_size;
264 			symlook_init(&req, name);
265 			req.ventry = fetch_ventry(dstobj,
266 			    ELF_R_SYM(rela->r_info));
267 			req.flags = SYMLOOK_EARLY;
268 
269 			for (srcobj = dstobj->next; srcobj != NULL;
270 			    srcobj = srcobj->next) {
271 				res = symlook_obj(&req, srcobj);
272 				if (res == 0) {
273 					srcsym = req.sym_out;
274 					defobj = req.defobj_out;
275 					break;
276 				}
277 			}
278 			if (srcobj == NULL) {
279 				_rtld_error("Undefined symbol \"%s\""
280 					    "referenced from COPY relocation"
281 					    "in %s", name, dstobj->path);
282 				return (-1);
283 			}
284 
285 			srcaddr = (const void *)(defobj->relocbase +
286 			    srcsym->st_value);
287 			memcpy(dstaddr, srcaddr, size);
288 		}
289 	}
290 
291 	return (0);
292 }
293 
294 int
reloc_non_plt(Obj_Entry * obj,Obj_Entry * obj_rtld,int flags,RtldLockState * lockstate)295 reloc_non_plt(Obj_Entry *obj, Obj_Entry *obj_rtld, int flags,
296     RtldLockState *lockstate)
297 {
298 	const Elf_Rela *relalim;
299 	const Elf_Rela *rela;
300 	SymCache *cache;
301 	int r = -1;
302 
303 	if ((flags & SYMLOOK_IFUNC) != 0)
304 		/* XXX not implemented */
305 		return (0);
306 
307 	/*
308 	 * The dynamic loader may be called from a thread, we have
309 	 * limited amounts of stack available so we cannot use alloca().
310 	 */
311 	if (obj != obj_rtld) {
312 		cache = calloc(obj->dynsymcount, sizeof(SymCache));
313 		/* No need to check for NULL here */
314 	} else
315 		cache = NULL;
316 
317 	relalim = (const Elf_Rela *)((caddr_t)obj->rela + obj->relasize);
318 	for (rela = obj->rela; rela < relalim; rela++) {
319 		if (reloc_nonplt_object(obj, rela, cache, flags, lockstate) < 0)
320 			goto done;
321 	}
322 	r = 0;
323 done:
324 	if (cache != NULL)
325 		free(cache);
326 	return (r);
327 }
328 
329 static int
reloc_nonplt_object(Obj_Entry * obj,const Elf_Rela * rela,SymCache * cache,int flags,RtldLockState * lockstate)330 reloc_nonplt_object(Obj_Entry *obj, const Elf_Rela *rela, SymCache *cache,
331     int flags, RtldLockState *lockstate)
332 {
333 	const Obj_Entry *defobj;
334 	const Elf_Sym *def;
335 	Elf_Addr *where;
336 	Elf_Word *where32;
337 	Elf_Word type;
338 	Elf_Addr value;
339 	Elf_Addr mask;
340 
341 	where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
342 	where32 = (Elf_Word *)where;
343 	defobj = NULL;
344 	def = NULL;
345 
346 	type = ELF64_R_TYPE_ID(rela->r_info);
347 	if (type == R_SPARC_NONE)
348 		return (0);
349 
350 	/* We do JMP_SLOTs below. */
351 	if (type == R_SPARC_JMP_SLOT)
352 		return (0);
353 
354 	/* COPY relocs are also handled elsewhere. */
355 	if (type == R_SPARC_COPY)
356 		return (0);
357 
358 	/* Ignore ADD and CALL relocations for dynamic TLS references. */
359 	if (type == R_SPARC_TLS_GD_ADD || type == R_SPARC_TLS_GD_CALL ||
360 	    type == R_SPARC_TLS_LDM_ADD || type == R_SPARC_TLS_LDM_CALL ||
361 	    type == R_SPARC_TLS_LDO_ADD)
362 		return (0);
363 
364 	/*
365 	 * Note: R_SPARC_TLS_TPOFF64 must be the numerically largest
366 	 * relocation type.
367 	 */
368 	if (type >= sizeof(reloc_target_bitmask) /
369 	    sizeof(*reloc_target_bitmask)) {
370 		_rtld_error("%s: Unsupported relocation type %d in non-PLT "
371 		    "object\n", obj->path, type);
372 		return (-1);
373 	}
374 
375 	value = rela->r_addend;
376 
377 	/*
378 	 * Handle relative relocs here, because we might not be able to access
379 	 * globals yet.
380 	 */
381 	if (type == R_SPARC_RELATIVE) {
382 		/* XXXX -- apparently we ignore the preexisting value. */
383 		*where = (Elf_Addr)(obj->relocbase + value);
384 		return (0);
385 	}
386 
387 	/*
388 	 * If we get here while relocating rtld itself, we will crash because
389 	 * a non-local variable is accessed.
390 	 */
391 	if (RELOC_RESOLVE_SYMBOL(type)) {
392 		/* Find the symbol. */
393 		def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj,
394 		    flags, cache, lockstate);
395 		if (def == NULL)
396 			return (-1);
397 
398 		if (RELOC_USE_TLS_ID(type))
399 			value = (Elf_Addr)defobj->tlsindex;
400 		else if (RELOC_USE_TLS_DOFF(type))
401 			value += (Elf_Addr)def->st_value;
402 		else if (RELOC_USE_TLS_OFF(type)) {
403 			/*
404 			 * We lazily allocate offsets for static TLS as we
405 			 * see the first relocation that references the TLS
406 			 * block.  This allows us to support (small amounts
407 			 * of) static TLS in dynamically loaded modules.  If
408 			 * we run out of space, we generate an error.
409 			 */
410 			if (!defobj->tls_done &&
411 			    !allocate_tls_offset((Obj_Entry*)defobj)) {
412 				_rtld_error("%s: No space available for "
413 				    "static Thread Local Storage", obj->path);
414 				return (-1);
415 			}
416 			value += (Elf_Addr)(def->st_value -
417 			    defobj->tlsoffset);
418 		} else {
419 			/* Add in the symbol's absolute address. */
420 			value += (Elf_Addr)(def->st_value +
421 			    defobj->relocbase);
422 		}
423 	}
424 
425 	if (type == R_SPARC_OLO10)
426 		value = (value & 0x3ff) + ELF64_R_TYPE_DATA(rela->r_info);
427 
428 	if (type == R_SPARC_HIX22 || type == R_SPARC_TLS_LE_HIX22)
429 		value ^= 0xffffffffffffffff;
430 
431 	if (RELOC_PC_RELATIVE(type))
432 		value -= (Elf_Addr)where;
433 
434 	if (RELOC_BASE_RELATIVE(type)) {
435 		/*
436 		 * Note that even though sparcs use `Elf_rela' exclusively
437 		 * we still need the implicit memory addend in relocations
438 		 * referring to GOT entries.  Undoubtedly, someone f*cked
439 		 * this up in the distant past, and now we're stuck with
440 		 * it in the name of compatibility for all eternity ...
441 		 *
442 		 * In any case, the implicit and explicit should be mutually
443 		 * exclusive.  We provide a check for that here.
444 		 */
445 		/* XXXX -- apparently we ignore the preexisting value */
446 		value += (Elf_Addr)(obj->relocbase);
447 	}
448 
449 	mask = RELOC_VALUE_BITMASK(type);
450 	value >>= RELOC_VALUE_RIGHTSHIFT(type);
451 	value &= mask;
452 
453 	if (type == R_SPARC_LOX10 || type == R_SPARC_TLS_LE_LOX10)
454 		value |= 0x1c00;
455 
456 	if (RELOC_UNALIGNED(type)) {
457 		/* Handle unaligned relocations. */
458 		Elf_Addr tmp;
459 		char *ptr;
460 		int size;
461 		int i;
462 
463 		size = RELOC_TARGET_SIZE(type) / 8;
464 		ptr = (char *)where;
465 		tmp = 0;
466 
467 		/* Read it in one byte at a time. */
468 		for (i = 0; i < size; i++)
469 			tmp = (tmp << 8) | ptr[i];
470 
471 		tmp &= ~mask;
472 		tmp |= value;
473 
474 		/* Write it back out. */
475 		for (i = 0; i < size; i++)
476 			ptr[i] = ((tmp >> ((size - i - 1) * 8)) & 0xff);
477 	} else if (RELOC_TARGET_SIZE(type) > 32) {
478 		*where &= ~mask;
479 		*where |= value;
480 	} else {
481 		*where32 &= ~mask;
482 		*where32 |= value;
483 	}
484 
485 	return (0);
486 }
487 
488 int
reloc_plt(Obj_Entry * obj)489 reloc_plt(Obj_Entry *obj)
490 {
491 #if 0
492 	const Obj_Entry *defobj;
493 	const Elf_Rela *relalim;
494 	const Elf_Rela *rela;
495 	const Elf_Sym *def;
496 	Elf_Addr *where;
497 	Elf_Addr value;
498 
499 	relalim = (const Elf_Rela *)((char *)obj->pltrela + obj->pltrelasize);
500 	for (rela = obj->pltrela; rela < relalim; rela++) {
501 		if (rela->r_addend == 0)
502 			continue;
503 		assert(ELF64_R_TYPE_ID(rela->r_info) == R_SPARC_JMP_SLOT);
504 		where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
505 		def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj,
506 		    true, NULL, lockstate);
507 		value = (Elf_Addr)(defobj->relocbase + def->st_value);
508 		*where = value;
509 	}
510 #endif
511 	return (0);
512 }
513 
514 /*
515  * Instruction templates:
516  */
517 #define	BAA	0x10400000	/*	ba,a	%xcc, 0 */
518 #define	SETHI	0x03000000	/*	sethi	%hi(0), %g1 */
519 #define	JMP	0x81c06000	/*	jmpl	%g1+%lo(0), %g0 */
520 #define	NOP	0x01000000	/*	sethi	%hi(0), %g0 */
521 #define	OR	0x82806000	/*	or	%g1, 0, %g1 */
522 #define	XOR	0x82c06000	/*	xor	%g1, 0, %g1 */
523 #define	MOV71	0x8283a000	/*	or	%o7, 0, %g1 */
524 #define	MOV17	0x9c806000	/*	or	%g1, 0, %o7 */
525 #define	CALL	0x40000000	/*	call	0 */
526 #define	SLLX	0x8b407000	/*	sllx	%g1, 0, %g1 */
527 #define	SETHIG5	0x0b000000	/*	sethi	%hi(0), %g5 */
528 #define	ORG5	0x82804005	/*	or	%g1, %g5, %g1 */
529 
530 /* %hi(v) with variable shift */
531 #define	HIVAL(v, s)	(((v) >> (s)) &  0x003fffff)
532 #define	LOVAL(v)	((v) & 0x000003ff)
533 
534 int
reloc_jmpslots(Obj_Entry * obj,int flags,RtldLockState * lockstate)535 reloc_jmpslots(Obj_Entry *obj, int flags, RtldLockState *lockstate)
536 {
537 	const Obj_Entry *defobj;
538 	const Elf_Rela *relalim;
539 	const Elf_Rela *rela;
540 	const Elf_Sym *def;
541 	Elf_Addr *where;
542 	Elf_Addr target;
543 
544 	relalim = (const Elf_Rela *)((char *)obj->pltrela + obj->pltrelasize);
545 	for (rela = obj->pltrela; rela < relalim; rela++) {
546 		assert(ELF64_R_TYPE_ID(rela->r_info) == R_SPARC_JMP_SLOT);
547 		where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
548 		def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj,
549 		    SYMLOOK_IN_PLT | flags, NULL, lockstate);
550 		if (def == NULL)
551 			return -1;
552 		target = (Elf_Addr)(defobj->relocbase + def->st_value);
553 		reloc_jmpslot(where, target, defobj, obj, (Elf_Rel *)rela);
554 	}
555 	obj->jmpslots_done = true;
556 	return (0);
557 }
558 
559 int
reloc_iresolve(Obj_Entry * obj,struct Struct_RtldLockState * lockstate)560 reloc_iresolve(Obj_Entry *obj, struct Struct_RtldLockState *lockstate)
561 {
562 
563 	/* XXX not implemented */
564 	return (0);
565 }
566 
567 int
reloc_gnu_ifunc(Obj_Entry * obj,int flags,struct Struct_RtldLockState * lockstate)568 reloc_gnu_ifunc(Obj_Entry *obj, int flags,
569     struct Struct_RtldLockState *lockstate)
570 {
571 
572 	/* XXX not implemented */
573 	return (0);
574 }
575 
576 Elf_Addr
reloc_jmpslot(Elf_Addr * wherep,Elf_Addr target,const Obj_Entry * obj,const Obj_Entry * refobj,const Elf_Rel * rel)577 reloc_jmpslot(Elf_Addr *wherep, Elf_Addr target, const Obj_Entry *obj,
578     const Obj_Entry *refobj, const Elf_Rel *rel)
579 {
580 	const Elf_Rela *rela = (const Elf_Rela *)rel;
581 	Elf_Addr offset;
582 	Elf_Word *where;
583 
584 	if (rela - refobj->pltrela < 32764) {
585 		/*
586 		 * At the PLT entry pointed at by `where', we now construct
587 		 * a direct transfer to the now fully resolved function
588 		 * address.
589 		 *
590 		 * A PLT entry is supposed to start by looking like this:
591 		 *
592 		 *	sethi	(. - .PLT0), %g1
593 		 *	ba,a	%xcc, .PLT1
594 		 *	nop
595 		 *	nop
596 		 *	nop
597 		 *	nop
598 		 *	nop
599 		 *	nop
600 		 *
601 		 * When we replace these entries we start from the second
602 		 * entry and do it in reverse order so the last thing we
603 		 * do is replace the branch.  That allows us to change this
604 		 * atomically.
605 		 *
606 		 * We now need to find out how far we need to jump.  We
607 		 * have a choice of several different relocation techniques
608 		 * which are increasingly expensive.
609 		 */
610 		where = (Elf_Word *)wherep;
611 		offset = ((Elf_Addr)where) - target;
612 		if (offset <= (1L<<20) && offset >= -(1L<<20)) {
613 			/*
614 			 * We're within 1MB -- we can use a direct branch
615 			 * instruction.
616 			 *
617 			 * We can generate this pattern:
618 			 *
619 			 *	sethi	%hi(. - .PLT0), %g1
620 			 *	ba,a	%xcc, addr
621 			 *	nop
622 			 *	nop
623 			 *	nop
624 			 *	nop
625 			 *	nop
626 			 *	nop
627 			 *
628 			 */
629 			where[1] = BAA | ((offset >> 2) &0x3fffff);
630 			flush(where, 4);
631 		} else if (target >= 0 && target < (1L<<32)) {
632 			/*
633 			 * We're within 32-bits of address zero.
634 			 *
635 			 * The resulting code in the jump slot is:
636 			 *
637 			 *	sethi	%hi(. - .PLT0), %g1
638 			 *	sethi	%hi(addr), %g1
639 			 *	jmp	%g1+%lo(addr)
640 			 *	nop
641 			 *	nop
642 			 *	nop
643 			 *	nop
644 			 *	nop
645 			 *
646 			 */
647 			where[2] = JMP   | LOVAL(target);
648 			flush(where, 8);
649 			where[1] = SETHI | HIVAL(target, 10);
650 			flush(where, 4);
651 		} else if (target <= 0 && target > -(1L<<32)) {
652 			/*
653 			 * We're within 32-bits of address -1.
654 			 *
655 			 * The resulting code in the jump slot is:
656 			 *
657 			 *	sethi	%hi(. - .PLT0), %g1
658 			 *	sethi	%hix(addr), %g1
659 			 *	xor	%g1, %lox(addr), %g1
660 			 *	jmp	%g1
661 			 *	nop
662 			 *	nop
663 			 *	nop
664 			 *	nop
665 			 *
666 			 */
667 			where[3] = JMP;
668 			flush(where, 12);
669 			where[2] = XOR | ((~target) & 0x00001fff);
670 			flush(where, 8);
671 			where[1] = SETHI | HIVAL(~target, 10);
672 			flush(where, 4);
673 		} else if (offset <= (1L<<32) && offset >= -((1L<<32) - 4)) {
674 			/*
675 			 * We're within 32-bits -- we can use a direct call
676 			 * insn
677 			 *
678 			 * The resulting code in the jump slot is:
679 			 *
680 			 *	sethi	%hi(. - .PLT0), %g1
681 			 *	mov	%o7, %g1
682 			 *	call	(.+offset)
683 			 *	 mov	%g1, %o7
684 			 *	nop
685 			 *	nop
686 			 *	nop
687 			 *	nop
688 			 *
689 			 */
690 			where[3] = MOV17;
691 			flush(where, 12);
692 			where[2] = CALL	  | ((offset >> 4) & 0x3fffffff);
693 			flush(where, 8);
694 			where[1] = MOV71;
695 			flush(where, 4);
696 		} else if (offset >= 0 && offset < (1L<<44)) {
697 			/*
698 			 * We're within 44 bits.  We can generate this
699 			 * pattern:
700 			 *
701 			 * The resulting code in the jump slot is:
702 			 *
703 			 *	sethi	%hi(. - .PLT0), %g1
704 			 *	sethi	%h44(addr), %g1
705 			 *	or	%g1, %m44(addr), %g1
706 			 *	sllx	%g1, 12, %g1
707 			 *	jmp	%g1+%l44(addr)
708 			 *	nop
709 			 *	nop
710 			 *	nop
711 			 *
712 			 */
713 			where[4] = JMP   | LOVAL(offset);
714 			flush(where, 16);
715 			where[3] = SLLX  | 12;
716 			flush(where, 12);
717 			where[2] = OR    | (((offset) >> 12) & 0x00001fff);
718 			flush(where, 8);
719 			where[1] = SETHI | HIVAL(offset, 22);
720 			flush(where, 4);
721 		} else if (offset < 0 && offset > -(1L<<44)) {
722 			/*
723 			 * We're within 44 bits.  We can generate this
724 			 * pattern:
725 			 *
726 			 * The resulting code in the jump slot is:
727 			 *
728 			 *	sethi	%hi(. - .PLT0), %g1
729 			 *	sethi	%h44(-addr), %g1
730 			 *	xor	%g1, %m44(-addr), %g1
731 			 *	sllx	%g1, 12, %g1
732 			 *	jmp	%g1+%l44(addr)
733 			 *	nop
734 			 *	nop
735 			 *	nop
736 			 *
737 			 */
738 			where[4] = JMP   | LOVAL(offset);
739 			flush(where, 16);
740 			where[3] = SLLX  | 12;
741 			flush(where, 12);
742 			where[2] = XOR   | (((~offset) >> 12) & 0x00001fff);
743 			flush(where, 8);
744 			where[1] = SETHI | HIVAL(~offset, 22);
745 			flush(where, 4);
746 		} else {
747 			/*
748 			 * We need to load all 64-bits
749 			 *
750 			 * The resulting code in the jump slot is:
751 			 *
752 			 *	sethi	%hi(. - .PLT0), %g1
753 			 *	sethi	%hh(addr), %g1
754 			 *	sethi	%lm(addr), %g5
755 			 *	or	%g1, %hm(addr), %g1
756 			 *	sllx	%g1, 32, %g1
757 			 *	or	%g1, %g5, %g1
758 			 *	jmp	%g1+%lo(addr)
759 			 *	nop
760 			 *
761 			 */
762 			where[6] = JMP     | LOVAL(target);
763 			flush(where, 24);
764 			where[5] = ORG5;
765 			flush(where, 20);
766 			where[4] = SLLX    | 32;
767 			flush(where, 16);
768 			where[3] = OR      | LOVAL((target) >> 32);
769 			flush(where, 12);
770 			where[2] = SETHIG5 | HIVAL(target, 10);
771 			flush(where, 8);
772 			where[1] = SETHI   | HIVAL(target, 42);
773 			flush(where, 4);
774 		}
775 	} else {
776 		/*
777 		 * This is a high PLT slot; the relocation offset specifies a
778 		 * pointer that needs to be frobbed; no actual code needs to
779 		 * be modified.  The pointer to be calculated needs the addend
780 		 * added and the reference object relocation base subtraced.
781 		 */
782 		*wherep = target + rela->r_addend -
783 		    (Elf_Addr)refobj->relocbase;
784 	}
785 
786 	return (target);
787 }
788 
789 /*
790  * Install rtld function call into this PLT slot.
791  */
792 #define	SAVE		0x9de3bf50
793 #define	SETHI_l0	0x21000000
794 #define	SETHI_l1	0x23000000
795 #define	OR_l0_l0	0xa0142000
796 #define	SLLX_l0_32_l0	0xa12c3020
797 #define	OR_l0_l1_l0	0xa0140011
798 #define	JMPL_l0_o1	0x93c42000
799 #define	MOV_g1_o0	0x90100001
800 
801 void
init_pltgot(Obj_Entry * obj)802 init_pltgot(Obj_Entry *obj)
803 {
804 	Elf_Word *entry;
805 
806 	if (obj->pltgot != NULL) {
807 		entry = (Elf_Word *)obj->pltgot;
808 		install_plt(&entry[0], (Elf_Addr)_rtld_bind_start_0);
809 		install_plt(&entry[8], (Elf_Addr)_rtld_bind_start_1);
810 		obj->pltgot[8] = (Elf_Addr)obj;
811 	}
812 }
813 
814 static void
install_plt(Elf_Word * pltgot,Elf_Addr proc)815 install_plt(Elf_Word *pltgot, Elf_Addr proc)
816 {
817 	pltgot[0] = SAVE;
818 	flush(pltgot, 0);
819 	pltgot[1] = SETHI_l0 | HIVAL(proc, 42);
820 	flush(pltgot, 4);
821 	pltgot[2] = SETHI_l1 | HIVAL(proc, 10);
822 	flush(pltgot, 8);
823 	pltgot[3] = OR_l0_l0 | LOVAL((proc) >> 32);
824 	flush(pltgot, 12);
825 	pltgot[4] = SLLX_l0_32_l0;
826 	flush(pltgot, 16);
827 	pltgot[5] = OR_l0_l1_l0;
828 	flush(pltgot, 20);
829 	pltgot[6] = JMPL_l0_o1 | LOVAL(proc);
830 	flush(pltgot, 24);
831 	pltgot[7] = MOV_g1_o0;
832 	flush(pltgot, 28);
833 }
834 
835 void
allocate_initial_tls(Obj_Entry * objs)836 allocate_initial_tls(Obj_Entry *objs)
837 {
838 	Elf_Addr* tpval;
839 
840 	/*
841 	 * Fix the size of the static TLS block by using the maximum offset
842 	 * allocated so far and adding a bit for dynamic modules to use.
843 	 */
844 	tls_static_space = tls_last_offset + RTLD_STATIC_TLS_EXTRA;
845 	tpval = allocate_tls(objs, NULL, 3 * sizeof(Elf_Addr),
846 	     sizeof(Elf_Addr));
847 	__asm __volatile("mov %0, %%g7" : : "r" (tpval));
848 }
849 
__tls_get_addr(tls_index * ti)850 void *__tls_get_addr(tls_index *ti)
851 {
852 	register Elf_Addr** tp __asm__("%g7");
853 
854 	return (tls_get_addr_common(tp, ti->ti_module, ti->ti_offset));
855 }
856