1 /* crypto/engine/eng_dyn.c */
2 /* Written by Geoff Thorpe (geoff@geoffthorpe.net) for the OpenSSL
5 /* ====================================================================
6 * Copyright (c) 1999-2001 The OpenSSL Project. All rights reserved.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
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
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/)"
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.
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.
34 * 6. Redistributions of any form whatsoever must retain the following
36 * "This product includes software developed by the OpenSSL Project
37 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
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 * ====================================================================
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).
61 #include <openssl/dso.h>
63 /* Shared libraries implementing ENGINEs for use by the "dynamic" ENGINE loader
64 * should implement the hook-up functions with the following prototypes. */
66 /* Our ENGINE handlers */
67 static int dynamic_init(ENGINE *e);
68 static int dynamic_finish(ENGINE *e);
69 static int dynamic_ctrl(ENGINE *e, int cmd, long i, void *p, void (*f)(void));
70 /* Predeclare our context type */
71 typedef struct st_dynamic_data_ctx dynamic_data_ctx;
72 /* The implementation for the important control command */
73 static int dynamic_load(ENGINE *e, dynamic_data_ctx *ctx);
75 #define DYNAMIC_CMD_SO_PATH ENGINE_CMD_BASE
76 #define DYNAMIC_CMD_NO_VCHECK (ENGINE_CMD_BASE + 1)
77 #define DYNAMIC_CMD_ID (ENGINE_CMD_BASE + 2)
78 #define DYNAMIC_CMD_LIST_ADD (ENGINE_CMD_BASE + 3)
79 #define DYNAMIC_CMD_DIR_LOAD (ENGINE_CMD_BASE + 4)
80 #define DYNAMIC_CMD_DIR_ADD (ENGINE_CMD_BASE + 5)
81 #define DYNAMIC_CMD_LOAD (ENGINE_CMD_BASE + 6)
83 /* The constants used when creating the ENGINE */
84 static const char *engine_dynamic_id = "dynamic";
85 static const char *engine_dynamic_name = "Dynamic engine loading support";
86 static const ENGINE_CMD_DEFN dynamic_cmd_defns[] = {
89 "Specifies the path to the new ENGINE shared library",
90 ENGINE_CMD_FLAG_STRING},
91 {DYNAMIC_CMD_NO_VCHECK,
93 "Specifies to continue even if version checking fails (boolean)",
94 ENGINE_CMD_FLAG_NUMERIC},
97 "Specifies an ENGINE id name for loading",
98 ENGINE_CMD_FLAG_STRING},
99 {DYNAMIC_CMD_LIST_ADD,
101 "Whether to add a loaded ENGINE to the internal list (0=no,1=yes,2=mandatory)",
102 ENGINE_CMD_FLAG_NUMERIC},
103 {DYNAMIC_CMD_DIR_LOAD,
105 "Specifies whether to load from 'DIR_ADD' directories (0=no,1=yes,2=mandatory)",
106 ENGINE_CMD_FLAG_NUMERIC},
107 {DYNAMIC_CMD_DIR_ADD,
109 "Adds a directory from which ENGINEs can be loaded",
110 ENGINE_CMD_FLAG_STRING},
113 "Load up the ENGINE specified by other settings",
114 ENGINE_CMD_FLAG_NO_INPUT},
118 /* Loading code stores state inside the ENGINE structure via the "ex_data"
119 * element. We load all our state into a single structure and use that as a
120 * single context in the "ex_data" stack. */
121 struct st_dynamic_data_ctx
123 /* The DSO object we load that supplies the ENGINE code */
125 /* The function pointer to the version checking shared library function */
126 dynamic_v_check_fn v_check;
127 /* The function pointer to the engine-binding shared library function */
128 dynamic_bind_engine bind_engine;
129 /* The default name/path for loading the shared library */
130 const char *DYNAMIC_LIBNAME;
131 /* Whether to continue loading on a version check failure */
133 /* If non-NULL, stipulates the 'id' of the ENGINE to be loaded */
134 const char *engine_id;
135 /* If non-zero, a successfully loaded ENGINE should be added to the internal
136 * ENGINE list. If 2, the add must succeed or the entire load should fail. */
138 /* The symbol name for the version checking function */
139 const char *DYNAMIC_F1;
140 /* The symbol name for the "initialise ENGINE structure" function */
141 const char *DYNAMIC_F2;
142 /* Whether to never use 'dirs', use 'dirs' as a fallback, or only use
143 * 'dirs' for loading. Default is to use 'dirs' as a fallback. */
145 /* A stack of directories from which ENGINEs could be loaded */
146 STACK_OF(OPENSSL_STRING) *dirs;
149 /* This is the "ex_data" index we obtain and reserve for use with our context
151 static int dynamic_ex_data_idx = -1;
153 static void int_free_str(char *s) { OPENSSL_free(s); }
154 /* Because our ex_data element may or may not get allocated depending on whether
155 * a "first-use" occurs before the ENGINE is freed, we have a memory leak
156 * problem to solve. We can't declare a "new" handler for the ex_data as we
157 * don't want a dynamic_data_ctx in *all* ENGINE structures of all types (this
158 * is a bug in the design of CRYPTO_EX_DATA). As such, we just declare a "free"
159 * handler and that will get called if an ENGINE is being destroyed and there
160 * was an ex_data element corresponding to our context type. */
161 static void dynamic_data_ctx_free_func(void *parent, void *ptr,
162 CRYPTO_EX_DATA *ad, int idx, long argl, void *argp)
166 dynamic_data_ctx *ctx = (dynamic_data_ctx *)ptr;
168 DSO_free(ctx->dynamic_dso);
169 if(ctx->DYNAMIC_LIBNAME)
170 OPENSSL_free((void*)ctx->DYNAMIC_LIBNAME);
172 OPENSSL_free((void*)ctx->engine_id);
174 sk_OPENSSL_STRING_pop_free(ctx->dirs, int_free_str);
179 /* Construct the per-ENGINE context. We create it blindly and then use a lock to
180 * check for a race - if so, all but one of the threads "racing" will have
181 * wasted their time. The alternative involves creating everything inside the
182 * lock which is far worse. */
183 static int dynamic_set_data_ctx(ENGINE *e, dynamic_data_ctx **ctx)
186 c = OPENSSL_malloc(sizeof(dynamic_data_ctx));
189 ENGINEerr(ENGINE_F_DYNAMIC_SET_DATA_CTX,ERR_R_MALLOC_FAILURE);
192 memset(c, 0, sizeof(dynamic_data_ctx));
193 c->dynamic_dso = NULL;
195 c->bind_engine = NULL;
196 c->DYNAMIC_LIBNAME = NULL;
199 c->list_add_value = 0;
200 c->DYNAMIC_F1 = "v_check";
201 c->DYNAMIC_F2 = "bind_engine";
203 c->dirs = sk_OPENSSL_STRING_new_null();
206 ENGINEerr(ENGINE_F_DYNAMIC_SET_DATA_CTX,ERR_R_MALLOC_FAILURE);
210 CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
211 if((*ctx = (dynamic_data_ctx *)ENGINE_get_ex_data(e,
212 dynamic_ex_data_idx)) == NULL)
214 /* Good, we're the first */
215 ENGINE_set_ex_data(e, dynamic_ex_data_idx, c);
219 CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
220 /* If we lost the race to set the context, c is non-NULL and *ctx is the
221 * context of the thread that won. */
227 /* This function retrieves the context structure from an ENGINE's "ex_data", or
228 * if it doesn't exist yet, sets it up. */
229 static dynamic_data_ctx *dynamic_get_data_ctx(ENGINE *e)
231 dynamic_data_ctx *ctx;
232 if(dynamic_ex_data_idx < 0)
234 /* Create and register the ENGINE ex_data, and associate our
235 * "free" function with it to ensure any allocated contexts get
236 * freed when an ENGINE goes underground. */
237 int new_idx = ENGINE_get_ex_new_index(0, NULL, NULL, NULL,
238 dynamic_data_ctx_free_func);
241 ENGINEerr(ENGINE_F_DYNAMIC_GET_DATA_CTX,ENGINE_R_NO_INDEX);
244 CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
245 /* Avoid a race by checking again inside this lock */
246 if(dynamic_ex_data_idx < 0)
248 /* Good, someone didn't beat us to it */
249 dynamic_ex_data_idx = new_idx;
252 CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
253 /* In theory we could "give back" the index here if
254 * (new_idx>-1), but it's not possible and wouldn't gain us much
257 ctx = (dynamic_data_ctx *)ENGINE_get_ex_data(e, dynamic_ex_data_idx);
258 /* Check if the context needs to be created */
259 if((ctx == NULL) && !dynamic_set_data_ctx(e, &ctx))
260 /* "set_data" will set errors if necessary */
265 static ENGINE *engine_dynamic(void)
267 ENGINE *ret = ENGINE_new();
270 if(!ENGINE_set_id(ret, engine_dynamic_id) ||
271 !ENGINE_set_name(ret, engine_dynamic_name) ||
272 !ENGINE_set_init_function(ret, dynamic_init) ||
273 !ENGINE_set_finish_function(ret, dynamic_finish) ||
274 !ENGINE_set_ctrl_function(ret, dynamic_ctrl) ||
275 !ENGINE_set_flags(ret, ENGINE_FLAGS_BY_ID_COPY) ||
276 !ENGINE_set_cmd_defns(ret, dynamic_cmd_defns))
284 void ENGINE_load_dynamic(void)
286 ENGINE *toadd = engine_dynamic();
289 /* If the "add" worked, it gets a structural reference. So either way,
290 * we release our just-created reference. */
292 /* If the "add" didn't work, it was probably a conflict because it was
293 * already added (eg. someone calling ENGINE_load_blah then calling
294 * ENGINE_load_builtin_engines() perhaps). */
298 static int dynamic_init(ENGINE *e)
300 /* We always return failure - the "dyanamic" engine itself can't be used
305 static int dynamic_finish(ENGINE *e)
307 /* This should never be called on account of "dynamic_init" always
312 static int dynamic_ctrl(ENGINE *e, int cmd, long i, void *p, void (*f)(void))
314 dynamic_data_ctx *ctx = dynamic_get_data_ctx(e);
319 ENGINEerr(ENGINE_F_DYNAMIC_CTRL,ENGINE_R_NOT_LOADED);
322 initialised = ((ctx->dynamic_dso == NULL) ? 0 : 1);
323 /* All our control commands require the ENGINE to be uninitialised */
326 ENGINEerr(ENGINE_F_DYNAMIC_CTRL,
327 ENGINE_R_ALREADY_LOADED);
332 case DYNAMIC_CMD_SO_PATH:
333 /* a NULL 'p' or a string of zero-length is the same thing */
334 if(p && (strlen((const char *)p) < 1))
336 if(ctx->DYNAMIC_LIBNAME)
337 OPENSSL_free((void*)ctx->DYNAMIC_LIBNAME);
339 ctx->DYNAMIC_LIBNAME = BUF_strdup(p);
341 ctx->DYNAMIC_LIBNAME = NULL;
342 return (ctx->DYNAMIC_LIBNAME ? 1 : 0);
343 case DYNAMIC_CMD_NO_VCHECK:
344 ctx->no_vcheck = ((i == 0) ? 0 : 1);
347 /* a NULL 'p' or a string of zero-length is the same thing */
348 if(p && (strlen((const char *)p) < 1))
351 OPENSSL_free((void*)ctx->engine_id);
353 ctx->engine_id = BUF_strdup(p);
355 ctx->engine_id = NULL;
356 return (ctx->engine_id ? 1 : 0);
357 case DYNAMIC_CMD_LIST_ADD:
358 if((i < 0) || (i > 2))
360 ENGINEerr(ENGINE_F_DYNAMIC_CTRL,
361 ENGINE_R_INVALID_ARGUMENT);
364 ctx->list_add_value = (int)i;
366 case DYNAMIC_CMD_LOAD:
367 return dynamic_load(e, ctx);
368 case DYNAMIC_CMD_DIR_LOAD:
369 if((i < 0) || (i > 2))
371 ENGINEerr(ENGINE_F_DYNAMIC_CTRL,
372 ENGINE_R_INVALID_ARGUMENT);
375 ctx->dir_load = (int)i;
377 case DYNAMIC_CMD_DIR_ADD:
378 /* a NULL 'p' or a string of zero-length is the same thing */
379 if(!p || (strlen((const char *)p) < 1))
381 ENGINEerr(ENGINE_F_DYNAMIC_CTRL,
382 ENGINE_R_INVALID_ARGUMENT);
386 char *tmp_str = BUF_strdup(p);
389 ENGINEerr(ENGINE_F_DYNAMIC_CTRL,
390 ERR_R_MALLOC_FAILURE);
393 sk_OPENSSL_STRING_insert(ctx->dirs, tmp_str, -1);
399 ENGINEerr(ENGINE_F_DYNAMIC_CTRL,ENGINE_R_CTRL_COMMAND_NOT_IMPLEMENTED);
403 static int int_load(dynamic_data_ctx *ctx)
406 /* Unless told not to, try a direct load */
407 if((ctx->dir_load != 2) && (DSO_load(ctx->dynamic_dso,
408 ctx->DYNAMIC_LIBNAME, NULL, 0)) != NULL)
410 /* If we're not allowed to use 'dirs' or we have none, fail */
411 if(!ctx->dir_load || (num = sk_OPENSSL_STRING_num(ctx->dirs)) < 1)
413 for(loop = 0; loop < num; loop++)
415 const char *s = sk_OPENSSL_STRING_value(ctx->dirs, loop);
416 char *merge = DSO_merge(ctx->dynamic_dso, ctx->DYNAMIC_LIBNAME, s);
419 if(DSO_load(ctx->dynamic_dso, merge, NULL, 0))
421 /* Found what we're looking for */
430 static int dynamic_load(ENGINE *e, dynamic_data_ctx *ctx)
435 if(!ctx->dynamic_dso)
436 ctx->dynamic_dso = DSO_new();
437 if(!ctx->DYNAMIC_LIBNAME)
441 ctx->DYNAMIC_LIBNAME =
442 DSO_convert_filename(ctx->dynamic_dso, ctx->engine_id);
446 ENGINEerr(ENGINE_F_DYNAMIC_LOAD,
447 ENGINE_R_DSO_NOT_FOUND);
448 DSO_free(ctx->dynamic_dso);
449 ctx->dynamic_dso = NULL;
452 /* We have to find a bind function otherwise it'll always end badly */
453 if(!(ctx->bind_engine = (dynamic_bind_engine)DSO_bind_func(
454 ctx->dynamic_dso, ctx->DYNAMIC_F2)))
456 ctx->bind_engine = NULL;
457 DSO_free(ctx->dynamic_dso);
458 ctx->dynamic_dso = NULL;
459 ENGINEerr(ENGINE_F_DYNAMIC_LOAD,
460 ENGINE_R_DSO_FAILURE);
463 /* Do we perform version checking? */
466 unsigned long vcheck_res = 0;
467 /* Now we try to find a version checking function and decide how
468 * to cope with failure if/when it fails. */
469 ctx->v_check = (dynamic_v_check_fn)DSO_bind_func(
470 ctx->dynamic_dso, ctx->DYNAMIC_F1);
472 vcheck_res = ctx->v_check(OSSL_DYNAMIC_VERSION);
473 /* We fail if the version checker veto'd the load *or* if it is
474 * deferring to us (by returning its version) and we think it is
476 if(vcheck_res < OSSL_DYNAMIC_OLDEST)
479 ctx->bind_engine = NULL;
481 DSO_free(ctx->dynamic_dso);
482 ctx->dynamic_dso = NULL;
483 ENGINEerr(ENGINE_F_DYNAMIC_LOAD,
484 ENGINE_R_VERSION_INCOMPATIBILITY);
488 /* First binary copy the ENGINE structure so that we can roll back if
489 * the hand-over fails */
490 memcpy(&cpy, e, sizeof(ENGINE));
491 /* Provide the ERR, "ex_data", memory, and locking callbacks so the
492 * loaded library uses our state rather than its own. FIXME: As noted in
493 * engine.h, much of this would be simplified if each area of code
494 * provided its own "summary" structure of all related callbacks. It
495 * would also increase opaqueness. */
496 fns.static_state = ENGINE_get_static_state();
497 fns.err_fns = ERR_get_implementation();
498 fns.ex_data_fns = CRYPTO_get_ex_data_implementation();
499 CRYPTO_get_mem_functions(&fns.mem_fns.malloc_cb,
500 &fns.mem_fns.realloc_cb,
501 &fns.mem_fns.free_cb);
502 fns.lock_fns.lock_locking_cb = CRYPTO_get_locking_callback();
503 fns.lock_fns.lock_add_lock_cb = CRYPTO_get_add_lock_callback();
504 fns.lock_fns.dynlock_create_cb = CRYPTO_get_dynlock_create_callback();
505 fns.lock_fns.dynlock_lock_cb = CRYPTO_get_dynlock_lock_callback();
506 fns.lock_fns.dynlock_destroy_cb = CRYPTO_get_dynlock_destroy_callback();
507 /* Now that we've loaded the dynamic engine, make sure no "dynamic"
508 * ENGINE elements will show through. */
509 engine_set_all_null(e);
511 /* Try to bind the ENGINE onto our own ENGINE structure */
512 if(!ctx->bind_engine(e, ctx->engine_id, &fns))
514 ctx->bind_engine = NULL;
516 DSO_free(ctx->dynamic_dso);
517 ctx->dynamic_dso = NULL;
518 ENGINEerr(ENGINE_F_DYNAMIC_LOAD,ENGINE_R_INIT_FAILED);
519 /* Copy the original ENGINE structure back */
520 memcpy(e, &cpy, sizeof(ENGINE));
523 /* Do we try to add this ENGINE to the internal list too? */
524 if(ctx->list_add_value > 0)
528 /* Do we tolerate this or fail? */
529 if(ctx->list_add_value > 1)
531 /* Fail - NB: By this time, it's too late to
532 * rollback, and trying to do so allows the
533 * bind_engine() code to have created leaks. We
534 * just have to fail where we are, after the
535 * ENGINE has changed. */
536 ENGINEerr(ENGINE_F_DYNAMIC_LOAD,
537 ENGINE_R_CONFLICTING_ENGINE_ID);