xref: /illumos-gate/usr/src/cmd/sgs/rtld/common/globals.c (revision 56726c7e)
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 (c) 1990, 2010, Oracle and/or its affiliates. All rights reserved.
27  * Copyright 2022 Oxide Computer Company
28  */
29 
30 #include	<sys/types.h>
31 #include	<sys/mman.h>
32 #include	<signal.h>
33 #include	<dlfcn.h>
34 #include	<synch.h>
35 #include	<debug.h>
36 #include	"_rtld.h"
37 
38 /*
39  * Declarations of global variables used in ld.so.
40  */
41 Rt_lock		rtldlock;
42 int		thr_flg_nolock = 0;
43 int		thr_flg_reenter = 0;
44 
45 /*
46  * Major link-map lists.
47  */
48 Lm_list		lml_main =	{ 0 };		/* the `main's link map list */
49 Lm_list		lml_rtld =	{ 0 };		/* rtld's link map list */
50 
51 /*
52  * Entrance count.  Each time ld.so.1 is entered following initial process
53  * setup, this count is bumped.  This value serves to identify the present
54  * ld.so.1 operation.
55  *
56  * An ld.so.1 operation can result in many symbol lookup requests (i.e., loading
57  * objects and relocating all symbolic bindings).  This count is used to protect
58  * against attempting to re-load a failed lazy load within a single call to
59  * ld.so.1, while allowing such attempts across calls.  Should a lazy load fail,
60  * the present operation identifier is saved in the current symbol lookup data
61  * block (Slookup).  Should a lazy load fall back operation be triggered, the
62  * identifier in the symbol lookup block is compared to the current ld.so.1
63  * entry count, and if the two are equal the fall back is skipped.
64  *
65  * With this count, there is a danger of wrap-around, although as an unsigned
66  * 32-bit value, it is highly unlikely that any application could usefully make
67  * 4.3 giga-calls into ld.so.1.  The worst that can occur is that a fall back
68  * lazy load isn't triggered.  However, most lazy loads that fail typically
69  * continue to fail unless the user takes corrective action (adds the necessary
70  * (fixed) dependencies to the system).
71  */
72 ulong_t		ld_entry_cnt = 1;
73 
74 /*
75  * BEGIN: Exposed to rtld_db, don't change without a coordinated handshake with
76  * librtld_db (remembering that librtld_db must be able to read old as well as
77  * current core files).
78  */
79 APlist		*dynlm_list = NULL;	/* dynamic list of link-maps */
80 /*
81  * END: Exposed to rtld_db
82  */
83 
84 Reglist		*reglist = NULL;	/* list of register symbols */
85 
86 /*
87  * Set of integers to track how many of what type of PLT's have been bound.
88  * This is only really interesting for SPARC since ia32 has only one PLT.
89  */
90 uint32_t	pltcnt21d = 0;
91 uint32_t	pltcnt24d = 0;
92 uint32_t	pltcntu32 = 0;
93 uint32_t	pltcntu44 = 0;
94 uint32_t	pltcntfull = 0;
95 uint32_t	pltcntfar = 0;
96 
97 /*
98  * AVL tree pointers.
99  */
100 avl_tree_t	*capavl = NULL;		/* capabilities files */
101 avl_tree_t	*nfavl = NULL;		/* not-found path names */
102 avl_tree_t	*spavl = NULL;		/* secure path names */
103 
104 /*
105  * Various other global data.
106  */
107 uint_t		rtld_flags = 0;
108 uint_t		rtld_flags2 = 0;
109 
110 Lc_desc		glcs[CI_MAX];		/* global external interfaces */
111 
112 const char	*procname = NULL;
113 const char	*rtldname = MSG_ORIG(MSG_FIL_RTLD);
114 
115 char		*lasterr = NULL;	/* string describing last error */
116 					/*    cleared by each dlerror() */
117 Interp		*interp = NULL;		/* ELF interpreter info */
118 APlist		*hdl_alp[HDLIST_SZ+2];	/* dlopen() handle list */
119 size_t		syspagsz = 0;		/* system page size */
120 ulong_t		at_flags = 0;		/* machine specific file flags */
121 Uts_desc	*uts = NULL;		/* utsname descriptor */
122 Isa_desc	*isa = NULL;		/* isalist descriptor */
123 
124 uint_t		audit_argcnt = 64;	/* no. of stack args to copy (default */
125 					/*    is all) */
126 Audit_desc	*auditors = NULL;	/* global auditors (LD_AUDIT) */
127 APlist		*aud_preinit = NULL;	/* list of objects defining local */
128 APlist		*aud_activity = NULL;	/*    preinit and activity auditors */
129 
130 const char	*rpl_audit = NULL;	/* replaceable LD_AUDIT string */
131 const char	*rpl_debug = NULL;	/* replaceable LD_DEBUG string */
132 const char	*rpl_ldflags = NULL;	/* replaceable LD_FLAGS string */
133 const char	*rpl_libpath = NULL;	/* replaceable LD_LIBRARY_PATH string */
134 Alist		*rpl_libdirs = NULL;	/*    and associated Pdesc list */
135 const char	*rpl_preload = NULL;	/* replaceable LD_PRELOAD string */
136 
137 const char	*prm_audit = NULL;	/* permanent LD_AUDIT string */
138 const char	*prm_debug = NULL;	/* permanent LD_DEBUG string */
139 const char	*prm_ldflags = NULL;	/* permanent LD_FLAGS string */
140 const char	*prm_libpath = NULL;	/* permanent LD_LIBRARY_PATH string */
141 Alist		*prm_libdirs = NULL;	/*    and associated Pdesc list */
142 const char	*prm_preload = NULL;	/* permanent LD_PRELOAD string */
143 
144 uint_t		env_info = 0;		/* information regarding environment */
145 					/*    variables */
146 int		killsig = SIGKILL;	/* signal sent on fatal exit */
147 APlist		*free_alp = NULL;	/* defragmentation list */
148 
149 /*
150  * Capabilities are provided by the system.  However, users can define an
151  * alternative set of system capabilities, where they can add, subtract, or
152  * override the system capabilities for testing purposes.  Furthermore, these
153  * alternative capabilities can be specified such that they only apply to
154  * specified files rather than to all objects.
155  *
156  * The org_scapset is relied upon by the amd64 version of elf_rtbndr to
157  * determine whether or not AVX registers are present in the system.
158  */
159 static Syscapset	scapset = { 0 };
160 Syscapset	*org_scapset = &scapset;	/* original system and */
161 Syscapset	*alt_scapset = &scapset;	/* alternative system */
162 						/*	capabilities */
163 
164 const char	*rpl_hwcap = NULL;	/* replaceable hwcap str */
165 const char	*rpl_sfcap = NULL;	/* replaceable sfcap str */
166 const char	*rpl_machcap = NULL;	/* replaceable machcap str */
167 const char	*rpl_platcap = NULL;	/* replaceable platcap str */
168 const char	*rpl_cap_files = NULL;	/* associated files */
169 
170 const char	*prm_hwcap = NULL;	/* permanent hwcap str */
171 const char	*prm_sfcap = NULL;	/* permanent sfcap str */
172 const char	*prm_machcap = NULL;	/* permanent machcap str */
173 const char	*prm_platcap = NULL;	/* permanent platcap str */
174 const char	*prm_cap_files = NULL;	/* associated files */
175 
176 /*
177  * Note, the debugging descriptor interposes on the default definition provided
178  * by liblddbg.  This is required as ld.so.1 must only have outstanding relative
179  * relocations.
180  */
181 static Dbg_desc	_dbg_desc = {0, 0, 0};
182 Dbg_desc	*dbg_desc = &_dbg_desc;	/* debugging descriptor */
183 const char	*dbg_file = NULL;	/* debugging directed to file */
184 
185 #pragma weak	environ = _environ	/* environ for PLT tracing - we */
186 char		**_environ = NULL;	/* supply the pair to satisfy any */
187 					/* libc requirements (hwmuldiv) */
188 
189 const char	*profile_name = NULL;	/* object being profiled */
190 const char	*profile_out = NULL;	/* profile output file */
191 const char	*profile_lib = NULL;	/* audit library to perform profile */
192 
193 uchar_t		search_rules[] = {	/* dependency search rules */
194 		RPLENV,			/*	replaceable LD_LIBRARY_PATH */
195 		PRMENV,			/*	permanent LD_LIBRARY_PATH */
196 		RUNPATH,		/*	callers runpath */
197 		DEFAULT,		/*	default library path */
198 		0
199 };
200 
201 Dl_argsinfo	argsinfo = { 0 };	/* process argument, environment and */
202 					/*	auxv information. */
203 
204 /*
205  * Frequently used messages are cached here to reduce _dgettext() overhead and
206  * also provide for resetting should the locale change (see _ld_libc()).
207  */
208 const char	*err_strs[ERR_NUM] = { NULL };
209 const char	*nosym_str = NULL;
210 
211 
212 /*
213  * Rejection error message tables.
214  */
215 const Msg
216 ldd_reject[SGS_REJ_NUM] = {
217 		MSG_STR_EMPTY,
218 		MSG_LDD_REJ_MACH,	/* MSG_INTL(MSG_LDD_REJ_MACH) */
219 		MSG_LDD_REJ_CLASS,	/* MSG_INTL(MSG_LDD_REJ_CLASS) */
220 		MSG_LDD_REJ_DATA,	/* MSG_INTL(MSG_LDD_REJ_DATA) */
221 		MSG_LDD_REJ_TYPE,	/* MSG_INTL(MSG_LDD_REJ_TYPE) */
222 		MSG_LDD_REJ_BADFLAG,	/* MSG_INTL(MSG_LDD_REJ_BADFLAG) */
223 		MSG_LDD_REJ_MISFLAG,	/* MSG_INTL(MSG_LDD_REJ_MISFLAG) */
224 		MSG_LDD_REJ_VERSION,	/* MSG_INTL(MSG_LDD_REJ_VERSION) */
225 		MSG_LDD_REJ_HAL,	/* MSG_INTL(MSG_LDD_REJ_HAL) */
226 		MSG_LDD_REJ_US3,	/* MSG_INTL(MSG_LDD_REJ_US3) */
227 		MSG_LDD_REJ_STR,	/* MSG_INTL(MSG_LDD_REJ_STR) */
228 		MSG_LDD_REJ_UNKFILE,	/* MSG_INTL(MSG_LDD_REJ_UNKFILE) */
229 		MSG_LDD_REJ_UNKCAP,	/* MSG_INTL(MSG_LDD_REJ_UNKCAP) */
230 		MSG_LDD_REJ_HWCAP_1,	/* MSG_INTL(MSG_LDD_REJ_HWCAP_1) */
231 		MSG_LDD_REJ_SFCAP_1,	/* MSG_INTL(MSG_LDD_REJ_SFCAP_1) */
232 		MSG_LDD_REJ_MACHCAP,	/* MSG_INTL(MSG_LDD_REJ_MACHCAP) */
233 		MSG_LDD_REJ_PLATCAP,	/* MSG_INTL(MSG_LDD_REJ_PLATCAP) */
234 		MSG_LDD_REJ_HWCAP_2,	/* MSG_INTL(MSG_LDD_REJ_HWCAP_2) */
235 		MSG_LDD_REJ_ARCHIVE,	/* MSG_INTL(MSG_LDD_REJ_ARCHIVE) */
236 		MSG_LDD_REJ_KMOD,	/* MSG_INTL(MSG_LDD_REJ_KMOD) */
237 		MSG_LDD_REJ_HWCAP_3	/* MSG_INTL(MSG_LDD_REJ_HWCAP_3) */
238 	};
239 #if SGS_REJ_NUM != (SGS_REJ_HWCAP_3 + 1)
240 #error SGS_REJ_NUM has changed
241 #endif
242 
243 const Msg
244 err_reject[SGS_REJ_NUM] = {
245 		MSG_STR_EMPTY,
246 		MSG_ERR_REJ_MACH,	/* MSG_INTL(MSG_ERR_REJ_MACH) */
247 		MSG_ERR_REJ_CLASS,	/* MSG_INTL(MSG_ERR_REJ_CLASS) */
248 		MSG_ERR_REJ_DATA,	/* MSG_INTL(MSG_ERR_REJ_DATA) */
249 		MSG_ERR_REJ_TYPE,	/* MSG_INTL(MSG_ERR_REJ_TYPE) */
250 		MSG_ERR_REJ_BADFLAG,	/* MSG_INTL(MSG_ERR_REJ_BADFLAG) */
251 		MSG_ERR_REJ_MISFLAG,	/* MSG_INTL(MSG_ERR_REJ_MISFLAG) */
252 		MSG_ERR_REJ_VERSION,	/* MSG_INTL(MSG_ERR_REJ_VERSION) */
253 		MSG_ERR_REJ_HAL,	/* MSG_INTL(MSG_ERR_REJ_HAL) */
254 		MSG_ERR_REJ_US3,	/* MSG_INTL(MSG_ERR_REJ_US3) */
255 		MSG_ERR_REJ_STR,	/* MSG_INTL(MSG_ERR_REJ_STR) */
256 		MSG_ERR_REJ_UNKFILE,	/* MSG_INTL(MSG_ERR_REJ_UNKFILE) */
257 		MSG_ERR_REJ_UNKCAP,	/* MSG_INTL(MSG_ERR_REJ_UNKCAP) */
258 		MSG_ERR_REJ_HWCAP_1,	/* MSG_INTL(MSG_ERR_REJ_HWCAP_1) */
259 		MSG_ERR_REJ_SFCAP_1,	/* MSG_INTL(MSG_ERR_REJ_SFCAP_1) */
260 		MSG_ERR_REJ_MACHCAP,	/* MSG_INTL(MSG_ERR_REJ_MACHCAP) */
261 		MSG_ERR_REJ_PLATCAP,	/* MSG_INTL(MSG_ERR_REJ_PLATCAP) */
262 		MSG_ERR_REJ_HWCAP_2,	/* MSG_INTL(MSG_ERR_REJ_HWCAP_2) */
263 		MSG_ERR_REJ_ARCHIVE,	/* MSG_INTL(MSG_ERR_REJ_ARCHIVE) */
264 		MSG_ERR_REJ_KMOD,	/* MSG_INTL(MSG_ERR_REJ_KMOD) */
265 		MSG_ERR_REJ_HWCAP_3	/* MSG_INTL(MSG_ERR_REJ_HWCAP_3) */
266 	};
267 #if SGS_REJ_NUM != (SGS_REJ_HWCAP_3 + 1)
268 #error SGS_REJ_NUM has changed
269 #endif
270 
271 const Msg
272 ldd_warn[SGS_REJ_NUM] = {
273 		MSG_STR_EMPTY,
274 		MSG_STR_EMPTY,
275 		MSG_STR_EMPTY,
276 		MSG_STR_EMPTY,
277 		MSG_STR_EMPTY,
278 		MSG_STR_EMPTY,
279 		MSG_STR_EMPTY,
280 		MSG_STR_EMPTY,
281 		MSG_STR_EMPTY,
282 		MSG_STR_EMPTY,
283 		MSG_STR_EMPTY,
284 		MSG_STR_EMPTY,
285 		MSG_LDD_WARN_UNKCAP,	/* MSG_INTL(MSG_LDD_WARN_UNKCAP) */
286 		MSG_LDD_WARN_HWCAP_1,	/* MSG_INTL(MSG_LDD_WARN_HWCAP_1) */
287 		MSG_LDD_WARN_SFCAP_1,	/* MSG_INTL(MSG_LDD_WARN_SFCAP_1) */
288 		MSG_LDD_WARN_MACHCAP,	/* MSG_INTL(MSG_LDD_WARN_MACHCAP) */
289 		MSG_LDD_WARN_PLATCAP,	/* MSG_INTL(MSG_LDD_WARN_PLATCAP) */
290 		MSG_LDD_WARN_HWCAP_2,	/* MSG_INTL(MSG_LDD_WARN_HWCAP_2) */
291 		MSG_STR_EMPTY,
292 		MSG_STR_EMPTY,
293 		MSG_LDD_WARN_HWCAP_3	/* MSG_INTL(MSG_LDD_WARN_HWCAP_3) */
294 	};
295 #if SGS_REJ_NUM != (SGS_REJ_HWCAP_3 + 1)
296 #error SGS_REJ_NUM has changed
297 #endif
298