xref: /illumos-gate/usr/src/cmd/sgs/rtld/sparc/_setup.c (revision ebb8ac07)
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 2009 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*
28  *	Copyright (c) 1988 AT&T
29  *	  All Rights Reserved
30  */
31 /*
32  * Copyright (c) 2012, Joyent, Inc.  All rights reserved.
33  */
34 
35 /*
36  * SPARC specific setup routine  -  relocate ld.so's symbols, setup its
37  * environment, map in loadable sections of the executable.
38  *
39  * Takes base address ld.so was loaded at, address of ld.so's dynamic
40  * structure, address of process environment pointers, address of auxiliary
41  * vector and * argv[0] (process name).
42  * If errors occur, send process signal - otherwise
43  * return executable's entry point to the bootstrap routine.
44  */
45 
46 #include	<signal.h>
47 #include	<stdlib.h>
48 #include	<sys/auxv.h>
49 #include	<sys/types.h>
50 #include	<sys/stat.h>
51 #include	<link.h>
52 #include	<dlfcn.h>
53 #include	"_rtld.h"
54 #include	"_audit.h"
55 #include	"msg.h"
56 #ifdef A_OUT
57 #include	"_a.out.h"
58 #endif /* A_OUT */
59 
60 /* VARARGS */
61 unsigned long
_setup(Boot * ebp,Dyn * ld_dyn)62 _setup(Boot *ebp, Dyn *ld_dyn)
63 {
64 	ulong_t		reladdr, relacount, ld_base = 0;
65 	ulong_t		relaent = 0;
66 	ulong_t		strtab, soname, interp_base = 0;
67 	char		*_rt_name, **_envp, **_argv;
68 	int		_syspagsz = 0, fd = -1;
69 	uint_t		_flags = 0;
70 	uint_t		hwcap[2] = { 0, 0 };
71 	Dyn		*dyn_ptr;
72 	Phdr		*phdr = NULL;
73 	Rt_map		*lmp;
74 	auxv_t		*auxv, *_auxv;
75 	uid_t		uid = (uid_t)-1, euid = (uid_t)-1;
76 	gid_t		gid = (gid_t)-1, egid = (gid_t)-1;
77 	char		*_platform = NULL, *_execname = NULL, *_emulator = NULL;
78 	int		auxflags = -1;
79 #ifdef	A_OUT
80 	void		*aoutdyn = NULL;
81 #endif	/* A_OUT */
82 
83 	/*
84 	 * Scan the bootstrap structure to pick up the basics.
85 	 */
86 	for (; ebp->eb_tag != EB_NULL; ebp++)
87 		switch (ebp->eb_tag) {
88 		case EB_DYNAMIC:
89 #ifdef A_OUT
90 			aoutdyn = (Link_dynamic *)ebp->eb_un.eb_val;
91 #endif /* A_OUT */
92 			break;
93 		case EB_LDSO_BASE:
94 			ld_base = (unsigned long)ebp->eb_un.eb_val;
95 			break;
96 		case EB_ARGV:
97 			_argv = (char **)ebp->eb_un.eb_ptr;
98 			break;
99 		case EB_ENVP:
100 			_envp = (char **)ebp->eb_un.eb_ptr;
101 			break;
102 		case EB_AUXV:
103 			_auxv = (auxv_t *)ebp->eb_un.eb_ptr;
104 			break;
105 		case EB_PAGESIZE:
106 			_syspagsz = (int)ebp->eb_un.eb_val;
107 			break;
108 		}
109 
110 	/*
111 	 * Search the aux. vector for the information passed by exec.
112 	 */
113 	for (auxv = _auxv; auxv->a_type != AT_NULL; auxv++) {
114 		switch (auxv->a_type) {
115 		case AT_EXECFD:
116 			/* this is the old exec that passes a file descriptor */
117 			fd = (int)auxv->a_un.a_val;
118 			break;
119 		case AT_FLAGS:
120 			/* processor flags (MAU available, etc) */
121 			_flags = auxv->a_un.a_val;
122 			break;
123 		case AT_PAGESZ:
124 			/* system page size */
125 			_syspagsz = (int)auxv->a_un.a_val;
126 			break;
127 		case AT_PHDR:
128 			/* address of the segment table */
129 			phdr = (Phdr *)auxv->a_un.a_ptr;
130 			break;
131 		case AT_BASE:
132 			/* interpreter base address */
133 			if (ld_base == 0)
134 				ld_base = auxv->a_un.a_val;
135 			interp_base = auxv->a_un.a_val;
136 			break;
137 		case AT_SUN_UID:
138 			/* effective user id for the executable */
139 			euid = (uid_t)auxv->a_un.a_val;
140 			break;
141 		case AT_SUN_RUID:
142 			/* real user id for the executable */
143 			uid = (uid_t)auxv->a_un.a_val;
144 			break;
145 		case AT_SUN_GID:
146 			/* effective group id for the executable */
147 			egid = (gid_t)auxv->a_un.a_val;
148 			break;
149 		case AT_SUN_RGID:
150 			/* real group id for the executable */
151 			gid = (gid_t)auxv->a_un.a_val;
152 			break;
153 		case AT_SUN_PLATFORM:
154 			/* platform name */
155 			_platform = auxv->a_un.a_ptr;
156 			break;
157 		case AT_SUN_EXECNAME:
158 			/* full pathname of execed object */
159 			_execname = auxv->a_un.a_ptr;
160 			break;
161 		case AT_SUN_AUXFLAGS:
162 			/* auxiliary flags */
163 			auxflags = (int)auxv->a_un.a_val;
164 			break;
165 		case AT_SUN_HWCAP:
166 			/* hardware capabilities */
167 			hwcap[0] = (uint_t)auxv->a_un.a_val;
168 			break;
169 		case AT_SUN_HWCAP2:
170 			/* hardware capabilities */
171 			hwcap[1] = (uint_t)auxv->a_un.a_val;
172 			break;
173 		case AT_SUN_EMULATOR:
174 			/* name of emulation library, if any */
175 			_emulator = auxv->a_un.a_ptr;
176 			break;
177 		}
178 	}
179 
180 	/*
181 	 * Get needed info from ld.so's dynamic structure.
182 	 */
183 	/* LINTED */
184 	dyn_ptr = (Dyn *)((char *)ld_dyn + ld_base);
185 	for (ld_dyn = dyn_ptr; ld_dyn->d_tag != DT_NULL; ld_dyn++) {
186 		switch (ld_dyn->d_tag) {
187 		case DT_RELA:
188 			reladdr = ld_dyn->d_un.d_ptr + ld_base;
189 			break;
190 		case DT_RELACOUNT:
191 			relacount = ld_dyn->d_un.d_val;
192 			break;
193 		case DT_RELAENT:
194 			relaent = ld_dyn->d_un.d_val;
195 			break;
196 		case DT_STRTAB:
197 			strtab = ld_dyn->d_un.d_ptr + ld_base;
198 			break;
199 		case DT_SONAME:
200 			soname = ld_dyn->d_un.d_val;
201 			break;
202 		}
203 	}
204 	_rt_name = (char *)strtab + soname;
205 
206 	/*
207 	 * If we don't have a RELAENT, just assume the size.
208 	 */
209 	if (relaent == 0)
210 		relaent = sizeof (Rela);
211 
212 	/*
213 	 * As all global symbol references within ld.so.1 are protected
214 	 * (symbolic), only RELATIVE and JMPSLOT relocations should be left
215 	 * to process at runtime.  Process all relative relocations now.
216 	 */
217 	for (; relacount; relacount--) {
218 		ulong_t	roffset;
219 
220 		roffset = ((Rela *)reladdr)->r_offset + ld_base;
221 		*((ulong_t *)roffset) = ld_base +
222 		    ((Rela *)reladdr)->r_addend;
223 		reladdr += relaent;
224 	}
225 
226 	/*
227 	 * If an emulation library is being used, use that as the linker's
228 	 * effective executable name. The real executable is not linked by this
229 	 * linker.
230 	 */
231 	if (_emulator != NULL) {
232 		_execname = _emulator;
233 		rtld_flags2 |= RT_FL2_BRANDED;
234 	}
235 
236 	/*
237 	 * Continue with generic startup processing.
238 	 */
239 	/* BEGIN CSTYLED */
240 	if ((lmp = setup((char **)_envp, (auxv_t *)_auxv, _flags, _platform,
241 	    _syspagsz, _rt_name, ld_base, interp_base, fd, phdr,
242 	    _execname, _argv, uid, euid, gid, egid,
243 #ifdef	A_OUT
244 	    aoutdyn, auxflags, hwcap)) == NULL) {
245 #else
246 	    /* CSTYLED */
247 	    NULL, auxflags, hwcap)) == NULL) {
248 #endif	/* A_OUT */
249 		rtldexit(&lml_main, 1);
250 	}
251 	/* END CSTYLED */
252 
253 	return (LM_ENTRY_PT(lmp)());
254 }
255