1 /* dso_dlfcn.c -*- mode:C; c-file-style: "eay" -*- */
2 /* Written by Geoff Thorpe (geoff@geoffthorpe.net) for the OpenSSL
3  * project 2000.
4  */
5 /* ====================================================================
6  * Copyright (c) 2000 The OpenSSL Project.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  *
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in
17  *    the documentation and/or other materials provided with the
18  *    distribution.
19  *
20  * 3. All advertising materials mentioning features or use of this
21  *    software must display the following acknowledgment:
22  *    "This product includes software developed by the OpenSSL Project
23  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
24  *
25  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
26  *    endorse or promote products derived from this software without
27  *    prior written permission. For written permission, please contact
28  *    licensing@OpenSSL.org.
29  *
30  * 5. Products derived from this software may not be called "OpenSSL"
31  *    nor may "OpenSSL" appear in their names without prior written
32  *    permission of the OpenSSL Project.
33  *
34  * 6. Redistributions of any form whatsoever must retain the following
35  *    acknowledgment:
36  *    "This product includes software developed by the OpenSSL Project
37  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
38  *
39  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
40  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
41  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
42  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
43  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
45  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
46  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
48  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
49  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
50  * OF THE POSSIBILITY OF SUCH DAMAGE.
51  * ====================================================================
52  *
53  * This product includes cryptographic software written by Eric Young
54  * (eay@cryptsoft.com).  This product includes software written by Tim
55  * Hudson (tjh@cryptsoft.com).
56  *
57  */
58 
59 /* We need to do this early, because stdio.h includes the header files
60    that handle _GNU_SOURCE and other similar macros.  Defining it later
61    is simply too late, because those headers are protected from re-
62    inclusion.  */
63 #ifdef __linux
64 # ifndef _GNU_SOURCE
65 #  define _GNU_SOURCE	/* make sure dladdr is declared */
66 # endif
67 #endif
68 
69 #include <stdio.h>
70 #include "cryptlib.h"
71 #include <openssl/dso.h>
72 
73 #ifndef DSO_DLFCN
74 DSO_METHOD *DSO_METHOD_dlfcn(void)
75 	{
76 	return NULL;
77 	}
78 #else
79 
80 #ifdef HAVE_DLFCN_H
81 # ifdef __osf__
82 #  define __EXTENSIONS__
83 # endif
84 # include <dlfcn.h>
85 # define HAVE_DLINFO 1
86 # if defined(_AIX) || defined(__CYGWIN__) || \
87      defined(__SCO_VERSION__) || defined(_SCO_ELF) || \
88      (defined(__osf__) && !defined(RTLD_NEXT))     || \
89      (defined(__OpenBSD__) && !defined(RTLD_SELF)) || \
90 	defined(__ANDROID__)
91 #  undef HAVE_DLINFO
92 # endif
93 #endif
94 
95 /* Part of the hack in "dlfcn_load" ... */
96 #define DSO_MAX_TRANSLATED_SIZE 256
97 
98 static int dlfcn_load(DSO *dso);
99 static int dlfcn_unload(DSO *dso);
100 static void *dlfcn_bind_var(DSO *dso, const char *symname);
101 static DSO_FUNC_TYPE dlfcn_bind_func(DSO *dso, const char *symname);
102 #if 0
103 static int dlfcn_unbind(DSO *dso, char *symname, void *symptr);
104 static int dlfcn_init(DSO *dso);
105 static int dlfcn_finish(DSO *dso);
106 static long dlfcn_ctrl(DSO *dso, int cmd, long larg, void *parg);
107 #endif
108 static char *dlfcn_name_converter(DSO *dso, const char *filename);
109 static char *dlfcn_merger(DSO *dso, const char *filespec1,
110 	const char *filespec2);
111 static int dlfcn_pathbyaddr(void *addr,char *path,int sz);
112 static void *dlfcn_globallookup(const char *name);
113 
114 static DSO_METHOD dso_meth_dlfcn = {
115 	"OpenSSL 'dlfcn' shared library method",
116 	dlfcn_load,
117 	dlfcn_unload,
118 	dlfcn_bind_var,
119 	dlfcn_bind_func,
120 /* For now, "unbind" doesn't exist */
121 #if 0
122 	NULL, /* unbind_var */
123 	NULL, /* unbind_func */
124 #endif
125 	NULL, /* ctrl */
126 	dlfcn_name_converter,
127 	dlfcn_merger,
128 	NULL, /* init */
129 	NULL, /* finish */
130 	dlfcn_pathbyaddr,
131 	dlfcn_globallookup
132 	};
133 
134 DSO_METHOD *DSO_METHOD_dlfcn(void)
135 	{
136 	return(&dso_meth_dlfcn);
137 	}
138 
139 /* Prior to using the dlopen() function, we should decide on the flag
140  * we send. There's a few different ways of doing this and it's a
141  * messy venn-diagram to match up which platforms support what. So
142  * as we don't have autoconf yet, I'm implementing a hack that could
143  * be hacked further relatively easily to deal with cases as we find
144  * them. Initially this is to cope with OpenBSD. */
145 #if defined(__OpenBSD__) || defined(__NetBSD__)
146 #	ifdef DL_LAZY
147 #		define DLOPEN_FLAG DL_LAZY
148 #	else
149 #		ifdef RTLD_NOW
150 #			define DLOPEN_FLAG RTLD_NOW
151 #		else
152 #			define DLOPEN_FLAG 0
153 #		endif
154 #	endif
155 #else
156 #	ifdef OPENSSL_SYS_SUNOS
157 #		define DLOPEN_FLAG 1
158 #	else
159 #		define DLOPEN_FLAG RTLD_NOW /* Hope this works everywhere else */
160 #	endif
161 #endif
162 
163 /* For this DSO_METHOD, our meth_data STACK will contain;
164  * (i) the handle (void*) returned from dlopen().
165  */
166 
167 static int dlfcn_load(DSO *dso)
168 	{
169 	void *ptr = NULL;
170 	/* See applicable comments in dso_dl.c */
171 	char *filename = DSO_convert_filename(dso, NULL);
172 	int flags = DLOPEN_FLAG;
173 
174 	if(filename == NULL)
175 		{
176 		DSOerr(DSO_F_DLFCN_LOAD,DSO_R_NO_FILENAME);
177 		goto err;
178 		}
179 
180 #ifdef RTLD_GLOBAL
181 	if (dso->flags & DSO_FLAG_GLOBAL_SYMBOLS)
182 		flags |= RTLD_GLOBAL;
183 #endif
184 	ptr = dlopen(filename, flags);
185 	if(ptr == NULL)
186 		{
187 		DSOerr(DSO_F_DLFCN_LOAD,DSO_R_LOAD_FAILED);
188 		ERR_add_error_data(4, "filename(", filename, "): ", dlerror());
189 		goto err;
190 		}
191 	if(!sk_void_push(dso->meth_data, (char *)ptr))
192 		{
193 		DSOerr(DSO_F_DLFCN_LOAD,DSO_R_STACK_ERROR);
194 		goto err;
195 		}
196 	/* Success */
197 	dso->loaded_filename = filename;
198 	return(1);
199 err:
200 	/* Cleanup! */
201 	if(filename != NULL)
202 		OPENSSL_free(filename);
203 	if(ptr != NULL)
204 		dlclose(ptr);
205 	return(0);
206 }
207 
208 static int dlfcn_unload(DSO *dso)
209 	{
210 	void *ptr;
211 	if(dso == NULL)
212 		{
213 		DSOerr(DSO_F_DLFCN_UNLOAD,ERR_R_PASSED_NULL_PARAMETER);
214 		return(0);
215 		}
216 	if(sk_void_num(dso->meth_data) < 1)
217 		return(1);
218 	ptr = sk_void_pop(dso->meth_data);
219 	if(ptr == NULL)
220 		{
221 		DSOerr(DSO_F_DLFCN_UNLOAD,DSO_R_NULL_HANDLE);
222 		/* Should push the value back onto the stack in
223 		 * case of a retry. */
224 		sk_void_push(dso->meth_data, ptr);
225 		return(0);
226 		}
227 	/* For now I'm not aware of any errors associated with dlclose() */
228 	dlclose(ptr);
229 	return(1);
230 	}
231 
232 static void *dlfcn_bind_var(DSO *dso, const char *symname)
233 	{
234 	void *ptr, *sym;
235 
236 	if((dso == NULL) || (symname == NULL))
237 		{
238 		DSOerr(DSO_F_DLFCN_BIND_VAR,ERR_R_PASSED_NULL_PARAMETER);
239 		return(NULL);
240 		}
241 	if(sk_void_num(dso->meth_data) < 1)
242 		{
243 		DSOerr(DSO_F_DLFCN_BIND_VAR,DSO_R_STACK_ERROR);
244 		return(NULL);
245 		}
246 	ptr = sk_void_value(dso->meth_data, sk_void_num(dso->meth_data) - 1);
247 	if(ptr == NULL)
248 		{
249 		DSOerr(DSO_F_DLFCN_BIND_VAR,DSO_R_NULL_HANDLE);
250 		return(NULL);
251 		}
252 	sym = dlsym(ptr, symname);
253 	if(sym == NULL)
254 		{
255 		DSOerr(DSO_F_DLFCN_BIND_VAR,DSO_R_SYM_FAILURE);
256 		ERR_add_error_data(4, "symname(", symname, "): ", dlerror());
257 		return(NULL);
258 		}
259 	return(sym);
260 	}
261 
262 static DSO_FUNC_TYPE dlfcn_bind_func(DSO *dso, const char *symname)
263 	{
264 	void *ptr;
265 	union {
266 		DSO_FUNC_TYPE sym;
267 		void *dlret;
268 	} u;
269 
270 	if((dso == NULL) || (symname == NULL))
271 		{
272 		DSOerr(DSO_F_DLFCN_BIND_FUNC,ERR_R_PASSED_NULL_PARAMETER);
273 		return(NULL);
274 		}
275 	if(sk_void_num(dso->meth_data) < 1)
276 		{
277 		DSOerr(DSO_F_DLFCN_BIND_FUNC,DSO_R_STACK_ERROR);
278 		return(NULL);
279 		}
280 	ptr = sk_void_value(dso->meth_data, sk_void_num(dso->meth_data) - 1);
281 	if(ptr == NULL)
282 		{
283 		DSOerr(DSO_F_DLFCN_BIND_FUNC,DSO_R_NULL_HANDLE);
284 		return(NULL);
285 		}
286 	u.dlret = dlsym(ptr, symname);
287 	if(u.dlret == NULL)
288 		{
289 		DSOerr(DSO_F_DLFCN_BIND_FUNC,DSO_R_SYM_FAILURE);
290 		ERR_add_error_data(4, "symname(", symname, "): ", dlerror());
291 		return(NULL);
292 		}
293 	return u.sym;
294 	}
295 
296 static char *dlfcn_merger(DSO *dso, const char *filespec1,
297 	const char *filespec2)
298 	{
299 	char *merged;
300 
301 	if(!filespec1 && !filespec2)
302 		{
303 		DSOerr(DSO_F_DLFCN_MERGER,
304 				ERR_R_PASSED_NULL_PARAMETER);
305 		return(NULL);
306 		}
307 	/* If the first file specification is a rooted path, it rules.
308 	   same goes if the second file specification is missing. */
309 	if (!filespec2 || (filespec1 != NULL && filespec1[0] == '/'))
310 		{
311 		merged = OPENSSL_malloc(strlen(filespec1) + 1);
312 		if(!merged)
313 			{
314 			DSOerr(DSO_F_DLFCN_MERGER, ERR_R_MALLOC_FAILURE);
315 			return(NULL);
316 			}
317 		strcpy(merged, filespec1);
318 		}
319 	/* If the first file specification is missing, the second one rules. */
320 	else if (!filespec1)
321 		{
322 		merged = OPENSSL_malloc(strlen(filespec2) + 1);
323 		if(!merged)
324 			{
325 			DSOerr(DSO_F_DLFCN_MERGER,
326 				ERR_R_MALLOC_FAILURE);
327 			return(NULL);
328 			}
329 		strcpy(merged, filespec2);
330 		}
331 	else
332 		/* This part isn't as trivial as it looks.  It assumes that
333 		   the second file specification really is a directory, and
334 		   makes no checks whatsoever.  Therefore, the result becomes
335 		   the concatenation of filespec2 followed by a slash followed
336 		   by filespec1. */
337 		{
338 		int spec2len, len;
339 
340 		spec2len = strlen(filespec2);
341 		len = spec2len + (filespec1 ? strlen(filespec1) : 0);
342 
343 		if(filespec2 && filespec2[spec2len - 1] == '/')
344 			{
345 			spec2len--;
346 			len--;
347 			}
348 		merged = OPENSSL_malloc(len + 2);
349 		if(!merged)
350 			{
351 			DSOerr(DSO_F_DLFCN_MERGER,
352 				ERR_R_MALLOC_FAILURE);
353 			return(NULL);
354 			}
355 		strcpy(merged, filespec2);
356 		merged[spec2len] = '/';
357 		strcpy(&merged[spec2len + 1], filespec1);
358 		}
359 	return(merged);
360 	}
361 
362 #ifdef OPENSSL_SYS_MACOSX
363 #define DSO_ext	".dylib"
364 #define DSO_extlen 6
365 #else
366 #define DSO_ext	".so"
367 #define DSO_extlen 3
368 #endif
369 
370 
371 static char *dlfcn_name_converter(DSO *dso, const char *filename)
372 	{
373 	char *translated;
374 	int len, rsize, transform;
375 
376 	len = strlen(filename);
377 	rsize = len + 1;
378 	transform = (strstr(filename, "/") == NULL);
379 	if(transform)
380 		{
381 		/* We will convert this to "%s.so" or "lib%s.so" etc */
382 		rsize += DSO_extlen;	/* The length of ".so" */
383 		if ((DSO_flags(dso) & DSO_FLAG_NAME_TRANSLATION_EXT_ONLY) == 0)
384 			rsize += 3; /* The length of "lib" */
385 		}
386 	translated = OPENSSL_malloc(rsize);
387 	if(translated == NULL)
388 		{
389 		DSOerr(DSO_F_DLFCN_NAME_CONVERTER,
390 				DSO_R_NAME_TRANSLATION_FAILED);
391 		return(NULL);
392 		}
393 	if(transform)
394 		{
395 		if ((DSO_flags(dso) & DSO_FLAG_NAME_TRANSLATION_EXT_ONLY) == 0)
396 			snprintf(translated, rsize, "lib%s" DSO_ext, filename);
397 		else
398 			snprintf(translated, rsize, "%s" DSO_ext, filename);
399 		}
400 	else
401 		snprintf(translated, rsize, "%s", filename);
402 	return(translated);
403 	}
404 
405 #ifdef __sgi
406 /*
407 This is a quote from IRIX manual for dladdr(3c):
408 
409      <dlfcn.h> does not contain a prototype for dladdr or definition of
410      Dl_info.  The #include <dlfcn.h>  in the SYNOPSIS line is traditional,
411      but contains no dladdr prototype and no IRIX library contains an
412      implementation.  Write your own declaration based on the code below.
413 
414      The following code is dependent on internal interfaces that are not
415      part of the IRIX compatibility guarantee; however, there is no future
416      intention to change this interface, so on a practical level, the code
417      below is safe to use on IRIX.
418 */
419 #include <rld_interface.h>
420 #ifndef _RLD_INTERFACE_DLFCN_H_DLADDR
421 #define _RLD_INTERFACE_DLFCN_H_DLADDR
422 typedef struct Dl_info {
423     const char * dli_fname;
424     void       * dli_fbase;
425     const char * dli_sname;
426     void       * dli_saddr;
427     int          dli_version;
428     int          dli_reserved1;
429     long         dli_reserved[4];
430 } Dl_info;
431 #else
432 typedef struct Dl_info Dl_info;
433 #endif
434 #define _RLD_DLADDR             14
435 
436 static int dladdr(void *address, Dl_info *dl)
437 {
438 	void *v;
439 	v = _rld_new_interface(_RLD_DLADDR,address,dl);
440 	return (int)v;
441 }
442 #endif /* __sgi */
443 
444 static int dlfcn_pathbyaddr(void *addr,char *path,int sz)
445 	{
446 #ifdef HAVE_DLINFO
447 	Dl_info dli;
448 	int len;
449 
450 	if (addr == NULL)
451 		{
452 		union	{ int(*f)(void*,char*,int); void *p; } t =
453 			{ dlfcn_pathbyaddr };
454 		addr = t.p;
455 		}
456 
457 	if (dladdr(addr,&dli))
458 		{
459 		len = (int)strlen(dli.dli_fname);
460 		if (sz <= 0) return len+1;
461 		if (len >= sz) len=sz-1;
462 		memcpy(path,dli.dli_fname,len);
463 		path[len++]=0;
464 		return len;
465 		}
466 
467 	ERR_add_error_data(4, "dlfcn_pathbyaddr(): ", dlerror());
468 #endif
469 	return -1;
470 	}
471 
472 static void *dlfcn_globallookup(const char *name)
473 	{
474 	void *ret = NULL,*handle = dlopen(NULL,RTLD_LAZY);
475 
476 	if (handle)
477 		{
478 		ret = dlsym(handle,name);
479 		dlclose(handle);
480 		}
481 
482 	return ret;
483 	}
484 #endif /* DSO_DLFCN */
485