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      1 /* dso_dlfcn.c -*- mode:C; c-file-style: "eay" -*- */
      2 /* Written by Geoff Thorpe (geoff (at) 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 (at) 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 (at) cryptsoft.com).  This product includes software written by Tim
     55  * Hudson (tjh (at) 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(__OpenBSD__) && !defined(RTLD_SELF))
     89 #  undef HAVE_DLINFO
     90 # endif
     91 #endif
     92 
     93 /* Part of the hack in "dlfcn_load" ... */
     94 #define DSO_MAX_TRANSLATED_SIZE 256
     95 
     96 static int dlfcn_load(DSO *dso);
     97 static int dlfcn_unload(DSO *dso);
     98 static void *dlfcn_bind_var(DSO *dso, const char *symname);
     99 static DSO_FUNC_TYPE dlfcn_bind_func(DSO *dso, const char *symname);
    100 #if 0
    101 static int dlfcn_unbind(DSO *dso, char *symname, void *symptr);
    102 static int dlfcn_init(DSO *dso);
    103 static int dlfcn_finish(DSO *dso);
    104 static long dlfcn_ctrl(DSO *dso, int cmd, long larg, void *parg);
    105 #endif
    106 static char *dlfcn_name_converter(DSO *dso, const char *filename);
    107 static char *dlfcn_merger(DSO *dso, const char *filespec1,
    108 	const char *filespec2);
    109 static int dlfcn_pathbyaddr(void *addr,char *path,int sz);
    110 static void *dlfcn_globallookup(const char *name);
    111 
    112 static DSO_METHOD dso_meth_dlfcn = {
    113 	"OpenSSL 'dlfcn' shared library method",
    114 	dlfcn_load,
    115 	dlfcn_unload,
    116 	dlfcn_bind_var,
    117 	dlfcn_bind_func,
    118 /* For now, "unbind" doesn't exist */
    119 #if 0
    120 	NULL, /* unbind_var */
    121 	NULL, /* unbind_func */
    122 #endif
    123 	NULL, /* ctrl */
    124 	dlfcn_name_converter,
    125 	dlfcn_merger,
    126 	NULL, /* init */
    127 	NULL, /* finish */
    128 	dlfcn_pathbyaddr,
    129 	dlfcn_globallookup
    130 	};
    131 
    132 DSO_METHOD *DSO_METHOD_dlfcn(void)
    133 	{
    134 	return(&dso_meth_dlfcn);
    135 	}
    136 
    137 /* Prior to using the dlopen() function, we should decide on the flag
    138  * we send. There's a few different ways of doing this and it's a
    139  * messy venn-diagram to match up which platforms support what. So
    140  * as we don't have autoconf yet, I'm implementing a hack that could
    141  * be hacked further relatively easily to deal with cases as we find
    142  * them. Initially this is to cope with OpenBSD. */
    143 #if defined(__OpenBSD__) || defined(__NetBSD__)
    144 #	ifdef DL_LAZY
    145 #		define DLOPEN_FLAG DL_LAZY
    146 #	else
    147 #		ifdef RTLD_NOW
    148 #			define DLOPEN_FLAG RTLD_NOW
    149 #		else
    150 #			define DLOPEN_FLAG 0
    151 #		endif
    152 #	endif
    153 #else
    154 #	ifdef OPENSSL_SYS_SUNOS
    155 #		define DLOPEN_FLAG 1
    156 #	else
    157 #		define DLOPEN_FLAG RTLD_NOW /* Hope this works everywhere else */
    158 #	endif
    159 #endif
    160 
    161 /* For this DSO_METHOD, our meth_data STACK will contain;
    162  * (i) the handle (void*) returned from dlopen().
    163  */
    164 
    165 static int dlfcn_load(DSO *dso)
    166 	{
    167 	void *ptr = NULL;
    168 	/* See applicable comments in dso_dl.c */
    169 	char *filename = DSO_convert_filename(dso, NULL);
    170 	int flags = DLOPEN_FLAG;
    171 
    172 	if(filename == NULL)
    173 		{
    174 		DSOerr(DSO_F_DLFCN_LOAD,DSO_R_NO_FILENAME);
    175 		goto err;
    176 		}
    177 
    178 #ifdef RTLD_GLOBAL
    179 	if (dso->flags & DSO_FLAG_GLOBAL_SYMBOLS)
    180 		flags |= RTLD_GLOBAL;
    181 #endif
    182 	ptr = dlopen(filename, flags);
    183 	if(ptr == NULL)
    184 		{
    185 		DSOerr(DSO_F_DLFCN_LOAD,DSO_R_LOAD_FAILED);
    186 		ERR_add_error_data(4, "filename(", filename, "): ", dlerror());
    187 		goto err;
    188 		}
    189 	if(!sk_void_push(dso->meth_data, (char *)ptr))
    190 		{
    191 		DSOerr(DSO_F_DLFCN_LOAD,DSO_R_STACK_ERROR);
    192 		goto err;
    193 		}
    194 	/* Success */
    195 	dso->loaded_filename = filename;
    196 	return(1);
    197 err:
    198 	/* Cleanup! */
    199 	if(filename != NULL)
    200 		OPENSSL_free(filename);
    201 	if(ptr != NULL)
    202 		dlclose(ptr);
    203 	return(0);
    204 }
    205 
    206 static int dlfcn_unload(DSO *dso)
    207 	{
    208 	void *ptr;
    209 	if(dso == NULL)
    210 		{
    211 		DSOerr(DSO_F_DLFCN_UNLOAD,ERR_R_PASSED_NULL_PARAMETER);
    212 		return(0);
    213 		}
    214 	if(sk_void_num(dso->meth_data) < 1)
    215 		return(1);
    216 	ptr = sk_void_pop(dso->meth_data);
    217 	if(ptr == NULL)
    218 		{
    219 		DSOerr(DSO_F_DLFCN_UNLOAD,DSO_R_NULL_HANDLE);
    220 		/* Should push the value back onto the stack in
    221 		 * case of a retry. */
    222 		sk_void_push(dso->meth_data, ptr);
    223 		return(0);
    224 		}
    225 	/* For now I'm not aware of any errors associated with dlclose() */
    226 	dlclose(ptr);
    227 	return(1);
    228 	}
    229 
    230 static void *dlfcn_bind_var(DSO *dso, const char *symname)
    231 	{
    232 	void *ptr, *sym;
    233 
    234 	if((dso == NULL) || (symname == NULL))
    235 		{
    236 		DSOerr(DSO_F_DLFCN_BIND_VAR,ERR_R_PASSED_NULL_PARAMETER);
    237 		return(NULL);
    238 		}
    239 	if(sk_void_num(dso->meth_data) < 1)
    240 		{
    241 		DSOerr(DSO_F_DLFCN_BIND_VAR,DSO_R_STACK_ERROR);
    242 		return(NULL);
    243 		}
    244 	ptr = sk_void_value(dso->meth_data, sk_void_num(dso->meth_data) - 1);
    245 	if(ptr == NULL)
    246 		{
    247 		DSOerr(DSO_F_DLFCN_BIND_VAR,DSO_R_NULL_HANDLE);
    248 		return(NULL);
    249 		}
    250 	sym = dlsym(ptr, symname);
    251 	if(sym == NULL)
    252 		{
    253 		DSOerr(DSO_F_DLFCN_BIND_VAR,DSO_R_SYM_FAILURE);
    254 		ERR_add_error_data(4, "symname(", symname, "): ", dlerror());
    255 		return(NULL);
    256 		}
    257 	return(sym);
    258 	}
    259 
    260 static DSO_FUNC_TYPE dlfcn_bind_func(DSO *dso, const char *symname)
    261 	{
    262 	void *ptr;
    263 	union {
    264 		DSO_FUNC_TYPE sym;
    265 		void *dlret;
    266 	} u;
    267 
    268 	if((dso == NULL) || (symname == NULL))
    269 		{
    270 		DSOerr(DSO_F_DLFCN_BIND_FUNC,ERR_R_PASSED_NULL_PARAMETER);
    271 		return(NULL);
    272 		}
    273 	if(sk_void_num(dso->meth_data) < 1)
    274 		{
    275 		DSOerr(DSO_F_DLFCN_BIND_FUNC,DSO_R_STACK_ERROR);
    276 		return(NULL);
    277 		}
    278 	ptr = sk_void_value(dso->meth_data, sk_void_num(dso->meth_data) - 1);
    279 	if(ptr == NULL)
    280 		{
    281 		DSOerr(DSO_F_DLFCN_BIND_FUNC,DSO_R_NULL_HANDLE);
    282 		return(NULL);
    283 		}
    284 	u.dlret = dlsym(ptr, symname);
    285 	if(u.dlret == NULL)
    286 		{
    287 		DSOerr(DSO_F_DLFCN_BIND_FUNC,DSO_R_SYM_FAILURE);
    288 		ERR_add_error_data(4, "symname(", symname, "): ", dlerror());
    289 		return(NULL);
    290 		}
    291 	return u.sym;
    292 	}
    293 
    294 static char *dlfcn_merger(DSO *dso, const char *filespec1,
    295 	const char *filespec2)
    296 	{
    297 	char *merged;
    298 
    299 	if(!filespec1 && !filespec2)
    300 		{
    301 		DSOerr(DSO_F_DLFCN_MERGER,
    302 				ERR_R_PASSED_NULL_PARAMETER);
    303 		return(NULL);
    304 		}
    305 	/* If the first file specification is a rooted path, it rules.
    306 	   same goes if the second file specification is missing. */
    307 	if (!filespec2 || (filespec1 != NULL && filespec1[0] == '/'))
    308 		{
    309 		merged = OPENSSL_malloc(strlen(filespec1) + 1);
    310 		if(!merged)
    311 			{
    312 			DSOerr(DSO_F_DLFCN_MERGER, ERR_R_MALLOC_FAILURE);
    313 			return(NULL);
    314 			}
    315 		strcpy(merged, filespec1);
    316 		}
    317 	/* If the first file specification is missing, the second one rules. */
    318 	else if (!filespec1)
    319 		{
    320 		merged = OPENSSL_malloc(strlen(filespec2) + 1);
    321 		if(!merged)
    322 			{
    323 			DSOerr(DSO_F_DLFCN_MERGER,
    324 				ERR_R_MALLOC_FAILURE);
    325 			return(NULL);
    326 			}
    327 		strcpy(merged, filespec2);
    328 		}
    329 	else
    330 		/* This part isn't as trivial as it looks.  It assumes that
    331 		   the second file specification really is a directory, and
    332 		   makes no checks whatsoever.  Therefore, the result becomes
    333 		   the concatenation of filespec2 followed by a slash followed
    334 		   by filespec1. */
    335 		{
    336 		int spec2len, len;
    337 
    338 		spec2len = strlen(filespec2);
    339 		len = spec2len + (filespec1 ? strlen(filespec1) : 0);
    340 
    341 		if(filespec2 && filespec2[spec2len - 1] == '/')
    342 			{
    343 			spec2len--;
    344 			len--;
    345 			}
    346 		merged = OPENSSL_malloc(len + 2);
    347 		if(!merged)
    348 			{
    349 			DSOerr(DSO_F_DLFCN_MERGER,
    350 				ERR_R_MALLOC_FAILURE);
    351 			return(NULL);
    352 			}
    353 		strcpy(merged, filespec2);
    354 		merged[spec2len] = '/';
    355 		strcpy(&merged[spec2len + 1], filespec1);
    356 		}
    357 	return(merged);
    358 	}
    359 
    360 #ifdef OPENSSL_SYS_MACOSX
    361 #define DSO_ext	".dylib"
    362 #define DSO_extlen 6
    363 #else
    364 #define DSO_ext	".so"
    365 #define DSO_extlen 3
    366 #endif
    367 
    368 
    369 static char *dlfcn_name_converter(DSO *dso, const char *filename)
    370 	{
    371 	char *translated;
    372 	int len, rsize, transform;
    373 
    374 	len = strlen(filename);
    375 	rsize = len + 1;
    376 	transform = (strstr(filename, "/") == NULL);
    377 	if(transform)
    378 		{
    379 		/* We will convert this to "%s.so" or "lib%s.so" etc */
    380 		rsize += DSO_extlen;	/* The length of ".so" */
    381 		if ((DSO_flags(dso) & DSO_FLAG_NAME_TRANSLATION_EXT_ONLY) == 0)
    382 			rsize += 3; /* The length of "lib" */
    383 		}
    384 	translated = OPENSSL_malloc(rsize);
    385 	if(translated == NULL)
    386 		{
    387 		DSOerr(DSO_F_DLFCN_NAME_CONVERTER,
    388 				DSO_R_NAME_TRANSLATION_FAILED);
    389 		return(NULL);
    390 		}
    391 	if(transform)
    392 		{
    393 		if ((DSO_flags(dso) & DSO_FLAG_NAME_TRANSLATION_EXT_ONLY) == 0)
    394 			sprintf(translated, "lib%s" DSO_ext, filename);
    395 		else
    396 			sprintf(translated, "%s" DSO_ext, filename);
    397 		}
    398 	else
    399 		sprintf(translated, "%s", filename);
    400 	return(translated);
    401 	}
    402 
    403 #ifdef __sgi
    404 /*
    405 This is a quote from IRIX manual for dladdr(3c):
    406 
    407      <dlfcn.h> does not contain a prototype for dladdr or definition of
    408      Dl_info.  The #include <dlfcn.h>  in the SYNOPSIS line is traditional,
    409      but contains no dladdr prototype and no IRIX library contains an
    410      implementation.  Write your own declaration based on the code below.
    411 
    412      The following code is dependent on internal interfaces that are not
    413      part of the IRIX compatibility guarantee; however, there is no future
    414      intention to change this interface, so on a practical level, the code
    415      below is safe to use on IRIX.
    416 */
    417 #include <rld_interface.h>
    418 #ifndef _RLD_INTERFACE_DLFCN_H_DLADDR
    419 #define _RLD_INTERFACE_DLFCN_H_DLADDR
    420 typedef struct Dl_info {
    421     const char * dli_fname;
    422     void       * dli_fbase;
    423     const char * dli_sname;
    424     void       * dli_saddr;
    425     int          dli_version;
    426     int          dli_reserved1;
    427     long         dli_reserved[4];
    428 } Dl_info;
    429 #else
    430 typedef struct Dl_info Dl_info;
    431 #endif
    432 #define _RLD_DLADDR             14
    433 
    434 static int dladdr(void *address, Dl_info *dl)
    435 {
    436 	void *v;
    437 	v = _rld_new_interface(_RLD_DLADDR,address,dl);
    438 	return (int)v;
    439 }
    440 #endif /* __sgi */
    441 
    442 static int dlfcn_pathbyaddr(void *addr,char *path,int sz)
    443 	{
    444 #ifdef HAVE_DLINFO
    445 	Dl_info dli;
    446 	int len;
    447 
    448 	if (addr == NULL)
    449 		{
    450 		union	{ int(*f)(void*,char*,int); void *p; } t =
    451 			{ dlfcn_pathbyaddr };
    452 		addr = t.p;
    453 		}
    454 
    455 	if (dladdr(addr,&dli))
    456 		{
    457 		len = (int)strlen(dli.dli_fname);
    458 		if (sz <= 0) return len+1;
    459 		if (len >= sz) len=sz-1;
    460 		memcpy(path,dli.dli_fname,len);
    461 		path[len++]=0;
    462 		return len;
    463 		}
    464 
    465 	ERR_add_error_data(4, "dlfcn_pathbyaddr(): ", dlerror());
    466 #endif
    467 	return -1;
    468 	}
    469 
    470 static void *dlfcn_globallookup(const char *name)
    471 	{
    472 	void *ret = NULL,*handle = dlopen(NULL,RTLD_LAZY);
    473 
    474 	if (handle)
    475 		{
    476 		ret = dlsym(handle,name);
    477 		dlclose(handle);
    478 		}
    479 
    480 	return ret;
    481 	}
    482 #endif /* DSO_DLFCN */
    483