xref: /onnv-gate/usr/src/cmd/sgs/rtld/sparc/common_sparc.c (revision 0:68f95e015346)
1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate  * CDDL HEADER START
3*0Sstevel@tonic-gate  *
4*0Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate  * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate  * (the "License").  You may not use this file except in compliance
7*0Sstevel@tonic-gate  * with the License.
8*0Sstevel@tonic-gate  *
9*0Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate  * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate  * and limitations under the License.
13*0Sstevel@tonic-gate  *
14*0Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate  *
20*0Sstevel@tonic-gate  * CDDL HEADER END
21*0Sstevel@tonic-gate  */
22*0Sstevel@tonic-gate /*
23*0Sstevel@tonic-gate  * Copyright 2000-2002 Sun Microsystems, Inc.  All rights reserved.
24*0Sstevel@tonic-gate  * Use is subject to license terms.
25*0Sstevel@tonic-gate  */
26*0Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"
27*0Sstevel@tonic-gate 
28*0Sstevel@tonic-gate 
29*0Sstevel@tonic-gate #include	<stdio.h>
30*0Sstevel@tonic-gate #include	<strings.h>
31*0Sstevel@tonic-gate #include	<sys/elf.h>
32*0Sstevel@tonic-gate #include	<sys/elf_SPARC.h>
33*0Sstevel@tonic-gate #include	<alloca.h>
34*0Sstevel@tonic-gate #include	"_rtld.h"
35*0Sstevel@tonic-gate #include	"_elf.h"
36*0Sstevel@tonic-gate #include	"msg.h"
37*0Sstevel@tonic-gate #include	"conv.h"
38*0Sstevel@tonic-gate 
39*0Sstevel@tonic-gate /*
40*0Sstevel@tonic-gate  *
41*0Sstevel@tonic-gate  *  Matrix of legal combinations of usage of a given register:
42*0Sstevel@tonic-gate  *
43*0Sstevel@tonic-gate  *	Obj1\Obj2       Scratch Named
44*0Sstevel@tonic-gate  *	Scratch          OK      NO
45*0Sstevel@tonic-gate  *	Named            NO      *
46*0Sstevel@tonic-gate  *
47*0Sstevel@tonic-gate  *  * OK if the symbols are identical, NO if they are not.  Two symbols
48*0Sstevel@tonic-gate  *  are identical if and only if one of the following is true:
49*0Sstevel@tonic-gate  *        A. They are both global and have the same name.
50*0Sstevel@tonic-gate  *        B. They are both local, have the same name, and are defined in
51*0Sstevel@tonic-gate  *        the same object.  (Note that a local symbol in one object is
52*0Sstevel@tonic-gate  *        never identical to a local symbol in another object, even if the
53*0Sstevel@tonic-gate  *        name is the same.)
54*0Sstevel@tonic-gate  *
55*0Sstevel@tonic-gate  *  Matrix of legal combinations of st_shndx for the same register symbol:
56*0Sstevel@tonic-gate  *
57*0Sstevel@tonic-gate  *	Obj1\Obj2       UNDEF   ABS
58*0Sstevel@tonic-gate  *	UNDEF            OK      OK
59*0Sstevel@tonic-gate  *	ABS              OK      NO
60*0Sstevel@tonic-gate  */
61*0Sstevel@tonic-gate 
62*0Sstevel@tonic-gate /*
63*0Sstevel@tonic-gate  * Test the compatiblity of two register symbols, 0 pass, >0 fail
64*0Sstevel@tonic-gate  */
65*0Sstevel@tonic-gate static uintptr_t
66*0Sstevel@tonic-gate check_regsyms(Sym * sym1, const char * name1, Sym * sym2, const char * name2)
67*0Sstevel@tonic-gate {
68*0Sstevel@tonic-gate 	if ((sym1->st_name == 0) && (sym2->st_name == 0))
69*0Sstevel@tonic-gate 		return (0);	/* scratches are always compatible */
70*0Sstevel@tonic-gate 
71*0Sstevel@tonic-gate 	if ((ELF_ST_BIND(sym1->st_info) == STB_LOCAL) ||
72*0Sstevel@tonic-gate 	    (ELF_ST_BIND(sym2->st_info) == STB_LOCAL)) {
73*0Sstevel@tonic-gate 		if (sym1->st_value == sym2->st_value)
74*0Sstevel@tonic-gate 			return (1);	/* local symbol incompat */
75*0Sstevel@tonic-gate 		return (0);		/* no other prob from locals */
76*0Sstevel@tonic-gate 	}
77*0Sstevel@tonic-gate 
78*0Sstevel@tonic-gate 	if (sym1->st_value == sym2->st_value) {
79*0Sstevel@tonic-gate 		/* NOTE this just avoids strcmp */
80*0Sstevel@tonic-gate 		if ((sym1->st_name == 0) || (sym2->st_name == 0))
81*0Sstevel@tonic-gate 			return (2);	/* can't match scratch to named */
82*0Sstevel@tonic-gate 
83*0Sstevel@tonic-gate 		if (strcmp(name1, name2) != 0)
84*0Sstevel@tonic-gate 			return (4);	/* diff name, same register value */
85*0Sstevel@tonic-gate 
86*0Sstevel@tonic-gate 		if ((sym1->st_shndx == SHN_ABS) && (sym2->st_shndx == SHN_ABS))
87*0Sstevel@tonic-gate 			return (3);	/* multiply defined */
88*0Sstevel@tonic-gate 	} else if (strcmp(name1, name2) == 0)
89*0Sstevel@tonic-gate 		return (5);	/* same name, diff register value */
90*0Sstevel@tonic-gate 
91*0Sstevel@tonic-gate 	return (0);
92*0Sstevel@tonic-gate }
93*0Sstevel@tonic-gate 
94*0Sstevel@tonic-gate int
95*0Sstevel@tonic-gate elf_regsyms(Rt_map * lmp)
96*0Sstevel@tonic-gate {
97*0Sstevel@tonic-gate 	Dyn *	dyn;
98*0Sstevel@tonic-gate 	Sym *	symdef;
99*0Sstevel@tonic-gate 	ulong_t	rsymndx;
100*0Sstevel@tonic-gate 
101*0Sstevel@tonic-gate 	/*
102*0Sstevel@tonic-gate 	 * Scan through the .dynamic section of this object looking for all
103*0Sstevel@tonic-gate 	 * DT_REGISTER entries.  For each DT_REGISTER entry found identify the
104*0Sstevel@tonic-gate 	 * register symbol it identifies and confirm that it doesn't conflict
105*0Sstevel@tonic-gate 	 * with any other register symbols.
106*0Sstevel@tonic-gate 	 */
107*0Sstevel@tonic-gate 	for (dyn = DYN(lmp); dyn->d_tag != DT_NULL; dyn++) {
108*0Sstevel@tonic-gate 		Reglist *	rp;
109*0Sstevel@tonic-gate 
110*0Sstevel@tonic-gate 		if ((dyn->d_tag != DT_SPARC_REGISTER) &&
111*0Sstevel@tonic-gate 		    (dyn->d_tag != DT_DEPRECATED_SPARC_REGISTER))
112*0Sstevel@tonic-gate 			continue;
113*0Sstevel@tonic-gate 
114*0Sstevel@tonic-gate 		/*
115*0Sstevel@tonic-gate 		 * Get the local symbol table entry.
116*0Sstevel@tonic-gate 		 */
117*0Sstevel@tonic-gate 		rsymndx = dyn->d_un.d_val;
118*0Sstevel@tonic-gate 		symdef = (Sym *)((unsigned long)SYMTAB(lmp) +
119*0Sstevel@tonic-gate 				(rsymndx * SYMENT(lmp)));
120*0Sstevel@tonic-gate 
121*0Sstevel@tonic-gate 		for (rp = reglist; rp; rp = rp->rl_next) {
122*0Sstevel@tonic-gate 			const char *	str, * sym1, * sym2;
123*0Sstevel@tonic-gate 
124*0Sstevel@tonic-gate 			if (rp->rl_sym == symdef) {
125*0Sstevel@tonic-gate 				/*
126*0Sstevel@tonic-gate 				 * Same symbol definition - everything is a-ok.
127*0Sstevel@tonic-gate 				 */
128*0Sstevel@tonic-gate 				return (1);
129*0Sstevel@tonic-gate 			}
130*0Sstevel@tonic-gate 
131*0Sstevel@tonic-gate 			sym1 = (STRTAB(rp->rl_lmp) + rp->rl_sym->st_name);
132*0Sstevel@tonic-gate 			sym2 = (STRTAB(lmp) + symdef->st_name);
133*0Sstevel@tonic-gate 
134*0Sstevel@tonic-gate 			if (check_regsyms(rp->rl_sym, sym1, symdef, sym2) == 0)
135*0Sstevel@tonic-gate 				continue;
136*0Sstevel@tonic-gate 
137*0Sstevel@tonic-gate 			if ((str = demangle(sym1)) != sym1) {
138*0Sstevel@tonic-gate 				char *	_str = alloca(strlen(str) + 1);
139*0Sstevel@tonic-gate 				(void) strcpy(_str, str);
140*0Sstevel@tonic-gate 				sym1 = (const char *)_str;
141*0Sstevel@tonic-gate 			}
142*0Sstevel@tonic-gate 			sym2 = demangle(sym2);
143*0Sstevel@tonic-gate 
144*0Sstevel@tonic-gate 			if (LIST(lmp)->lm_flags & LML_FLG_TRC_WARN) {
145*0Sstevel@tonic-gate 				(void) printf(MSG_INTL(MSG_LDD_REG_SYMCONF),
146*0Sstevel@tonic-gate 				    conv_sym_SPARC_value_str(symdef->st_value),
147*0Sstevel@tonic-gate 				    NAME(rp->rl_lmp), sym1, NAME(lmp), sym2);
148*0Sstevel@tonic-gate 			} else {
149*0Sstevel@tonic-gate 				eprintf(ERR_FATAL, MSG_INTL(MSG_REG_SYMCONF),
150*0Sstevel@tonic-gate 				    conv_sym_SPARC_value_str(symdef->st_value),
151*0Sstevel@tonic-gate 				    NAME(rp->rl_lmp), sym1, NAME(lmp), sym2);
152*0Sstevel@tonic-gate 				return (0);
153*0Sstevel@tonic-gate 			}
154*0Sstevel@tonic-gate 		}
155*0Sstevel@tonic-gate 		if ((rp = calloc(sizeof (Reglist), 1)) == (Reglist *)0)
156*0Sstevel@tonic-gate 			return (0);
157*0Sstevel@tonic-gate 		rp->rl_lmp = lmp;
158*0Sstevel@tonic-gate 		rp->rl_sym = symdef;
159*0Sstevel@tonic-gate 		rp->rl_next = reglist;
160*0Sstevel@tonic-gate 		reglist = rp;
161*0Sstevel@tonic-gate 	}
162*0Sstevel@tonic-gate 	return (1);
163*0Sstevel@tonic-gate }
164*0Sstevel@tonic-gate 
165*0Sstevel@tonic-gate 
166*0Sstevel@tonic-gate /*
167*0Sstevel@tonic-gate  * When the relocation loop realizes that it's dealing with relative
168*0Sstevel@tonic-gate  * relocations in a shared object, it breaks into this tighter loop
169*0Sstevel@tonic-gate  * as an optimization.
170*0Sstevel@tonic-gate  */
171*0Sstevel@tonic-gate ulong_t
172*0Sstevel@tonic-gate elf_reloc_relative(ulong_t relbgn, ulong_t relend, ulong_t relsiz,
173*0Sstevel@tonic-gate     ulong_t basebgn, ulong_t etext, ulong_t emap)
174*0Sstevel@tonic-gate {
175*0Sstevel@tonic-gate 	ulong_t roffset = ((Rela *) relbgn)->r_offset;
176*0Sstevel@tonic-gate 	Byte rtype;
177*0Sstevel@tonic-gate 
178*0Sstevel@tonic-gate 	do {
179*0Sstevel@tonic-gate 		roffset += basebgn;
180*0Sstevel@tonic-gate 
181*0Sstevel@tonic-gate 		/*
182*0Sstevel@tonic-gate 		 * If this relocation is against an address not mapped in,
183*0Sstevel@tonic-gate 		 * then break out of the relative relocation loop, falling
184*0Sstevel@tonic-gate 		 * back on the main relocation loop.
185*0Sstevel@tonic-gate 		 */
186*0Sstevel@tonic-gate 		if (roffset < etext || roffset > emap)
187*0Sstevel@tonic-gate 			break;
188*0Sstevel@tonic-gate 
189*0Sstevel@tonic-gate 		/*
190*0Sstevel@tonic-gate 		 * Perform the actual relocation.
191*0Sstevel@tonic-gate 		 */
192*0Sstevel@tonic-gate 		*((ulong_t *)roffset) +=
193*0Sstevel@tonic-gate 		    basebgn + (long)(((Rela *)relbgn)->r_addend);
194*0Sstevel@tonic-gate 
195*0Sstevel@tonic-gate 		relbgn += relsiz;
196*0Sstevel@tonic-gate 
197*0Sstevel@tonic-gate 		if (relbgn >= relend)
198*0Sstevel@tonic-gate 			break;
199*0Sstevel@tonic-gate 
200*0Sstevel@tonic-gate 		rtype = (Byte)ELF_R_TYPE(((Rela *)relbgn)->r_info);
201*0Sstevel@tonic-gate 		roffset = ((Rela *)relbgn)->r_offset;
202*0Sstevel@tonic-gate 
203*0Sstevel@tonic-gate 	} while (rtype == R_SPARC_RELATIVE);
204*0Sstevel@tonic-gate 
205*0Sstevel@tonic-gate 	return (relbgn);
206*0Sstevel@tonic-gate }
207*0Sstevel@tonic-gate 
208*0Sstevel@tonic-gate /*
209*0Sstevel@tonic-gate  * This is the tightest loop for RELATIVE relocations for those
210*0Sstevel@tonic-gate  * objects built with the DT_RELACOUNT .dynamic entry.
211*0Sstevel@tonic-gate  */
212*0Sstevel@tonic-gate ulong_t
213*0Sstevel@tonic-gate elf_reloc_relacount(ulong_t relbgn, ulong_t relacount, ulong_t relsiz,
214*0Sstevel@tonic-gate     ulong_t basebgn)
215*0Sstevel@tonic-gate {
216*0Sstevel@tonic-gate 	ulong_t roffset = ((Rela *) relbgn)->r_offset;
217*0Sstevel@tonic-gate 
218*0Sstevel@tonic-gate 	for (; relacount; relacount--) {
219*0Sstevel@tonic-gate 		roffset += basebgn;
220*0Sstevel@tonic-gate 
221*0Sstevel@tonic-gate 		/*
222*0Sstevel@tonic-gate 		 * Perform the actual relocation.
223*0Sstevel@tonic-gate 		 */
224*0Sstevel@tonic-gate 		*((ulong_t *)roffset) =
225*0Sstevel@tonic-gate 		    basebgn + (long)(((Rela *)relbgn)->r_addend);
226*0Sstevel@tonic-gate 
227*0Sstevel@tonic-gate 		relbgn += relsiz;
228*0Sstevel@tonic-gate 
229*0Sstevel@tonic-gate 		roffset = ((Rela *)relbgn)->r_offset;
230*0Sstevel@tonic-gate 	}
231*0Sstevel@tonic-gate 
232*0Sstevel@tonic-gate 	return (relbgn);
233*0Sstevel@tonic-gate }
234