xref: /illumos-gate/usr/src/cmd/sgs/rtld/sparc/_setup.c (revision 07678296)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  *	Copyright (c) 1988 AT&T
24  *	  All Rights Reserved
25  *
26  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
27  * Use is subject to license terms.
28  */
29 #pragma ident	"%Z%%M%	%I%	%E% SMI"
30 
31 /*
32  * SPARC specific setup routine  -  relocate ld.so's symbols, setup its
33  * environment, map in loadable sections of the executable.
34  *
35  * Takes base address ld.so was loaded at, address of ld.so's dynamic
36  * structure, address of process environment pointers, address of auxiliary
37  * vector and * argv[0] (process name).
38  * If errors occur, send process signal - otherwise
39  * return executable's entry point to the bootstrap routine.
40  */
41 #include	"_synonyms.h"
42 
43 #include	<signal.h>
44 #include	<stdlib.h>
45 #include	<fcntl.h>
46 #include	<stdio.h>
47 #include	<sys/auxv.h>
48 #include	<sys/types.h>
49 #include	<sys/stat.h>
50 #include	<link.h>
51 #include	<dlfcn.h>
52 #include	"_rtld.h"
53 #include	"_audit.h"
54 #include	"msg.h"
55 #ifdef A_OUT
56 #include	"_a.out.h"
57 #endif /* A_OUT */
58 
59 extern int	_end;
60 extern int	_etext;
61 extern void	_init(void);
62 
63 
64 /* VARARGS */
65 unsigned long
66 _setup(Boot * ebp, Dyn * ld_dyn)
67 {
68 	unsigned long	reladdr, relacount, ld_base = 0;
69 	unsigned long	relaent = 0;
70 	unsigned long	strtab, soname, interp_base = 0;
71 	char		*_rt_name, **_envp, **_argv;
72 	int		_syspagsz = 0, fd = -1, dz_fd = FD_UNAVAIL;
73 	uint_t		_flags = 0, hwcap_1 = 0;
74 	Dyn *		dyn_ptr;
75 	Phdr *		phdr = 0;
76 	Rt_map *	lmp;
77 	auxv_t		*auxv, *_auxv;
78 	uid_t		uid = (uid_t)-1, euid = (uid_t)-1;
79 	gid_t		gid = (gid_t)-1, egid = (gid_t)-1;
80 	char		*_platform = 0, *_execname = 0, *_emulator = 0;
81 	int		auxflags = -1;
82 #ifdef	A_OUT
83 	void *		aoutdyn = 0;
84 #endif	/* A_OUT */
85 
86 	/*
87 	 * Scan the bootstrap structure to pick up the basics.
88 	 */
89 	for (; ebp->eb_tag != EB_NULL; ebp++)
90 		switch (ebp->eb_tag) {
91 		case EB_DYNAMIC:
92 #ifdef A_OUT
93 			aoutdyn = (struct link_dynamic *)ebp->eb_un.eb_val;
94 #endif /* A_OUT */
95 			break;
96 		case EB_LDSO_BASE:
97 			ld_base = (unsigned long)ebp->eb_un.eb_val;
98 			break;
99 		case EB_ARGV:
100 			_argv = (char **)ebp->eb_un.eb_ptr;
101 			break;
102 		case EB_ENVP:
103 			_envp = (char **)ebp->eb_un.eb_ptr;
104 			break;
105 		case EB_AUXV:
106 			_auxv = (auxv_t *)ebp->eb_un.eb_ptr;
107 			break;
108 		case EB_DEVZERO:
109 			dz_fd = (int)ebp->eb_un.eb_val;
110 			break;
111 		case EB_PAGESIZE:
112 			_syspagsz = (int)ebp->eb_un.eb_val;
113 			break;
114 		}
115 
116 	/*
117 	 * Search the aux. vector for the information passed by exec.
118 	 */
119 	for (auxv = _auxv; auxv->a_type != AT_NULL; auxv++) {
120 		switch (auxv->a_type) {
121 		case AT_EXECFD:
122 			/* this is the old exec that passes a file descriptor */
123 			fd = (int)auxv->a_un.a_val;
124 			break;
125 		case AT_FLAGS:
126 			/* processor flags (MAU available, etc) */
127 			_flags = auxv->a_un.a_val;
128 			break;
129 		case AT_PAGESZ:
130 			/* system page size */
131 			_syspagsz = (int)auxv->a_un.a_val;
132 			break;
133 		case AT_PHDR:
134 			/* address of the segment table */
135 			phdr = (Phdr *)auxv->a_un.a_ptr;
136 			break;
137 		case AT_BASE:
138 			/* interpreter base address */
139 			if (ld_base == 0)
140 				ld_base = auxv->a_un.a_val;
141 			interp_base = auxv->a_un.a_val;
142 			break;
143 		case AT_SUN_UID:
144 			/* effective user id for the executable */
145 			euid = (uid_t)auxv->a_un.a_val;
146 			break;
147 		case AT_SUN_RUID:
148 			/* real user id for the executable */
149 			uid = (uid_t)auxv->a_un.a_val;
150 			break;
151 		case AT_SUN_GID:
152 			/* effective group id for the executable */
153 			egid = (gid_t)auxv->a_un.a_val;
154 			break;
155 		case AT_SUN_RGID:
156 			/* real group id for the executable */
157 			gid = (gid_t)auxv->a_un.a_val;
158 			break;
159 #ifdef	AT_SUN_PLATFORM			/* Defined on SunOS 5.5 & greater. */
160 		case AT_SUN_PLATFORM:
161 			/* platform name */
162 			_platform = auxv->a_un.a_ptr;
163 			break;
164 #endif
165 #ifdef	AT_SUN_EXECNAME			/* Defined on SunOS 5.6 & greater. */
166 		case AT_SUN_EXECNAME:
167 			/* full pathname of execed object */
168 			_execname = auxv->a_un.a_ptr;
169 			break;
170 #endif
171 #ifdef	AT_SUN_AUXFLAGS			/* At the behest of PSARC 2002/188 */
172 		case AT_SUN_AUXFLAGS:
173 			auxflags = (int)auxv->a_un.a_val;
174 			break;
175 #endif
176 #ifdef	AT_SUN_HWCAP			/* Hardware capabilities */
177 		case AT_SUN_HWCAP:
178 			hwcap_1 = (uint_t)auxv->a_un.a_val;
179 			break;
180 #endif
181 #ifdef  AT_SUN_EMULATOR			/* Emulation library name */
182 		case AT_SUN_EMULATOR:
183 			/* name of emulation library, if any */
184 			_emulator = auxv->a_un.a_ptr;
185 			break;
186 #endif
187 		}
188 	}
189 
190 	/*
191 	 * Get needed info from ld.so's dynamic structure.
192 	 */
193 	/* LINTED */
194 	dyn_ptr = (Dyn *)((char *)ld_dyn + ld_base);
195 	for (ld_dyn = dyn_ptr; ld_dyn->d_tag != DT_NULL; ld_dyn++) {
196 		switch (ld_dyn->d_tag) {
197 		case DT_RELA:
198 			reladdr = ld_dyn->d_un.d_ptr + ld_base;
199 			break;
200 		case DT_RELACOUNT:
201 			relacount = ld_dyn->d_un.d_val;
202 			break;
203 		case DT_RELAENT:
204 			relaent = ld_dyn->d_un.d_val;
205 			break;
206 		case DT_STRTAB:
207 			strtab = ld_dyn->d_un.d_ptr + ld_base;
208 			break;
209 		case DT_SONAME:
210 			soname = ld_dyn->d_un.d_val;
211 			break;
212 		}
213 	}
214 	_rt_name = (char *)strtab + soname;
215 
216 	/*
217 	 * If we don't have a RELAENT, just assume
218 	 * the size.
219 	 */
220 	if (relaent == 0)
221 		relaent = sizeof (Rela);
222 
223 	/*
224 	 * Because ld.so.1 is built with -Bsymbolic there should only be
225 	 * RELATIVE and JMPSLOT relocations.  Process all relatives first.
226 	 */
227 	for (; relacount; relacount--) {
228 		ulong_t	roffset;
229 
230 		roffset = ((Rela *)reladdr)->r_offset + ld_base;
231 		*((ulong_t *)roffset) = ld_base +
232 		    (long)(((Rela *)reladdr)->r_addend);
233 		reladdr += relaent;
234 	}
235 
236 	/*
237 	 * If an emulation library is being used, use that as the linker's
238 	 * effective executable name. The real executable is not linked by this
239 	 * linker.
240 	 */
241 	if (_emulator != NULL) {
242 		_execname = _emulator;
243 		rtld_flags2 |= RT_FL2_BRANDED;
244 	}
245 
246 	/*
247 	 * Continue with generic startup processing.
248 	 */
249 	if ((lmp = setup((char **)_envp, (auxv_t *)_auxv, _flags, _platform,
250 	    _syspagsz, _rt_name, dyn_ptr, ld_base, interp_base, fd, phdr,
251 	    _execname, _argv, dz_fd, uid, euid, gid, egid,
252 #ifdef	A_OUT
253 	    aoutdyn, auxflags, hwcap_1)) == (Rt_map *)0) {
254 #else
255 	    NULL, auxflags, hwcap_1)) == NULL) {
256 #endif	/* A_OUT */
257 		rtldexit(&lml_main, 1);
258 	}
259 
260 	return (LM_ENTRY_PT(lmp)());
261 }
262