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/crypto.h>
64 #include <openssl/engine.h>
65 #include <openssl/dso.h>
67 /* Shared libraries implementing ENGINEs for use by the "dynamic" ENGINE loader
68 * should implement the hook-up functions with the following prototypes. */
70 /* Our ENGINE handlers */
71 static int dynamic_init(ENGINE *e);
72 static int dynamic_finish(ENGINE *e);
73 static int dynamic_ctrl(ENGINE *e, int cmd, long i, void *p, void (*f)(void));
74 /* Predeclare our context type */
75 typedef struct st_dynamic_data_ctx dynamic_data_ctx;
76 /* The implementation for the important control command */
77 static int dynamic_load(ENGINE *e, dynamic_data_ctx *ctx);
79 #define DYNAMIC_CMD_SO_PATH ENGINE_CMD_BASE
80 #define DYNAMIC_CMD_NO_VCHECK (ENGINE_CMD_BASE + 1)
81 #define DYNAMIC_CMD_ID (ENGINE_CMD_BASE + 2)
82 #define DYNAMIC_CMD_LIST_ADD (ENGINE_CMD_BASE + 3)
83 #define DYNAMIC_CMD_DIR_LOAD (ENGINE_CMD_BASE + 4)
84 #define DYNAMIC_CMD_DIR_ADD (ENGINE_CMD_BASE + 5)
85 #define DYNAMIC_CMD_LOAD (ENGINE_CMD_BASE + 6)
87 /* The constants used when creating the ENGINE */
88 static const char *engine_dynamic_id = "dynamic";
89 static const char *engine_dynamic_name = "Dynamic engine loading support";
90 static const ENGINE_CMD_DEFN dynamic_cmd_defns[] = {
93 "Specifies the path to the new ENGINE shared library",
94 ENGINE_CMD_FLAG_STRING},
95 {DYNAMIC_CMD_NO_VCHECK,
97 "Specifies to continue even if version checking fails (boolean)",
98 ENGINE_CMD_FLAG_NUMERIC},
101 "Specifies an ENGINE id name for loading",
102 ENGINE_CMD_FLAG_STRING},
103 {DYNAMIC_CMD_LIST_ADD,
105 "Whether to add a loaded ENGINE to the internal list (0=no,1=yes,2=mandatory)",
106 ENGINE_CMD_FLAG_NUMERIC},
107 {DYNAMIC_CMD_DIR_LOAD,
109 "Specifies whether to load from 'DIR_ADD' directories (0=no,1=yes,2=mandatory)",
110 ENGINE_CMD_FLAG_NUMERIC},
111 {DYNAMIC_CMD_DIR_ADD,
113 "Adds a directory from which ENGINEs can be loaded",
114 ENGINE_CMD_FLAG_STRING},
117 "Load up the ENGINE specified by other settings",
118 ENGINE_CMD_FLAG_NO_INPUT},
121 static const ENGINE_CMD_DEFN dynamic_cmd_defns_empty[] = {
125 /* Loading code stores state inside the ENGINE structure via the "ex_data"
126 * element. We load all our state into a single structure and use that as a
127 * single context in the "ex_data" stack. */
128 struct st_dynamic_data_ctx
130 /* The DSO object we load that supplies the ENGINE code */
132 /* The function pointer to the version checking shared library function */
133 dynamic_v_check_fn v_check;
134 /* The function pointer to the engine-binding shared library function */
135 dynamic_bind_engine bind_engine;
136 /* The default name/path for loading the shared library */
137 const char *DYNAMIC_LIBNAME;
138 /* Whether to continue loading on a version check failure */
140 /* If non-NULL, stipulates the 'id' of the ENGINE to be loaded */
141 const char *engine_id;
142 /* If non-zero, a successfully loaded ENGINE should be added to the internal
143 * ENGINE list. If 2, the add must succeed or the entire load should fail. */
145 /* The symbol name for the version checking function */
146 const char *DYNAMIC_F1;
147 /* The symbol name for the "initialise ENGINE structure" function */
148 const char *DYNAMIC_F2;
149 /* Whether to never use 'dirs', use 'dirs' as a fallback, or only use
150 * 'dirs' for loading. Default is to use 'dirs' as a fallback. */
152 /* A stack of directories from which ENGINEs could be loaded */
156 /* This is the "ex_data" index we obtain and reserve for use with our context
158 static int dynamic_ex_data_idx = -1;
160 static void int_free_str(void *s) { OPENSSL_free(s); }
161 /* Because our ex_data element may or may not get allocated depending on whether
162 * a "first-use" occurs before the ENGINE is freed, we have a memory leak
163 * problem to solve. We can't declare a "new" handler for the ex_data as we
164 * don't want a dynamic_data_ctx in *all* ENGINE structures of all types (this
165 * is a bug in the design of CRYPTO_EX_DATA). As such, we just declare a "free"
166 * handler and that will get called if an ENGINE is being destroyed and there
167 * was an ex_data element corresponding to our context type. */
168 static void dynamic_data_ctx_free_func(void *parent, void *ptr,
169 CRYPTO_EX_DATA *ad, int idx, long argl, void *argp)
173 dynamic_data_ctx *ctx = (dynamic_data_ctx *)ptr;
175 DSO_free(ctx->dynamic_dso);
176 if(ctx->DYNAMIC_LIBNAME)
177 OPENSSL_free((void*)ctx->DYNAMIC_LIBNAME);
179 OPENSSL_free((void*)ctx->engine_id);
181 sk_pop_free(ctx->dirs, int_free_str);
186 /* Construct the per-ENGINE context. We create it blindly and then use a lock to
187 * check for a race - if so, all but one of the threads "racing" will have
188 * wasted their time. The alternative involves creating everything inside the
189 * lock which is far worse. */
190 static int dynamic_set_data_ctx(ENGINE *e, dynamic_data_ctx **ctx)
193 c = OPENSSL_malloc(sizeof(dynamic_data_ctx));
196 ENGINEerr(ENGINE_F_SET_DATA_CTX,ERR_R_MALLOC_FAILURE);
199 memset(c, 0, sizeof(dynamic_data_ctx));
200 c->dynamic_dso = NULL;
202 c->bind_engine = NULL;
203 c->DYNAMIC_LIBNAME = NULL;
206 c->list_add_value = 0;
207 c->DYNAMIC_F1 = "v_check";
208 c->DYNAMIC_F2 = "bind_engine";
210 c->dirs = sk_new_null();
213 ENGINEerr(ENGINE_F_SET_DATA_CTX,ERR_R_MALLOC_FAILURE);
217 CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
218 if((*ctx = (dynamic_data_ctx *)ENGINE_get_ex_data(e,
219 dynamic_ex_data_idx)) == NULL)
221 /* Good, we're the first */
222 ENGINE_set_ex_data(e, dynamic_ex_data_idx, c);
226 CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
227 /* If we lost the race to set the context, c is non-NULL and *ctx is the
228 * context of the thread that won. */
234 /* This function retrieves the context structure from an ENGINE's "ex_data", or
235 * if it doesn't exist yet, sets it up. */
236 static dynamic_data_ctx *dynamic_get_data_ctx(ENGINE *e)
238 dynamic_data_ctx *ctx;
239 if(dynamic_ex_data_idx < 0)
241 /* Create and register the ENGINE ex_data, and associate our
242 * "free" function with it to ensure any allocated contexts get
243 * freed when an ENGINE goes underground. */
244 int new_idx = ENGINE_get_ex_new_index(0, NULL, NULL, NULL,
245 dynamic_data_ctx_free_func);
248 ENGINEerr(ENGINE_F_DYNAMIC_GET_DATA_CTX,ENGINE_R_NO_INDEX);
251 CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
252 /* Avoid a race by checking again inside this lock */
253 if(dynamic_ex_data_idx < 0)
255 /* Good, someone didn't beat us to it */
256 dynamic_ex_data_idx = new_idx;
259 CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
260 /* In theory we could "give back" the index here if
261 * (new_idx>-1), but it's not possible and wouldn't gain us much
264 ctx = (dynamic_data_ctx *)ENGINE_get_ex_data(e, dynamic_ex_data_idx);
265 /* Check if the context needs to be created */
266 if((ctx == NULL) && !dynamic_set_data_ctx(e, &ctx))
267 /* "set_data" will set errors if necessary */
272 static ENGINE *engine_dynamic(void)
274 ENGINE *ret = ENGINE_new();
277 if(!ENGINE_set_id(ret, engine_dynamic_id) ||
278 !ENGINE_set_name(ret, engine_dynamic_name) ||
279 !ENGINE_set_init_function(ret, dynamic_init) ||
280 !ENGINE_set_finish_function(ret, dynamic_finish) ||
281 !ENGINE_set_ctrl_function(ret, dynamic_ctrl) ||
282 !ENGINE_set_flags(ret, ENGINE_FLAGS_BY_ID_COPY) ||
283 !ENGINE_set_cmd_defns(ret, dynamic_cmd_defns))
291 void ENGINE_load_dynamic(void)
293 ENGINE *toadd = engine_dynamic();
296 /* If the "add" worked, it gets a structural reference. So either way,
297 * we release our just-created reference. */
299 /* If the "add" didn't work, it was probably a conflict because it was
300 * already added (eg. someone calling ENGINE_load_blah then calling
301 * ENGINE_load_builtin_engines() perhaps). */
305 static int dynamic_init(ENGINE *e)
307 /* We always return failure - the "dyanamic" engine itself can't be used
312 static int dynamic_finish(ENGINE *e)
314 /* This should never be called on account of "dynamic_init" always
319 static int dynamic_ctrl(ENGINE *e, int cmd, long i, void *p, void (*f)(void))
321 dynamic_data_ctx *ctx = dynamic_get_data_ctx(e);
326 ENGINEerr(ENGINE_F_DYNAMIC_CTRL,ENGINE_R_NOT_LOADED);
329 initialised = ((ctx->dynamic_dso == NULL) ? 0 : 1);
330 /* All our control commands require the ENGINE to be uninitialised */
333 ENGINEerr(ENGINE_F_DYNAMIC_CTRL,
334 ENGINE_R_ALREADY_LOADED);
339 case DYNAMIC_CMD_SO_PATH:
340 /* a NULL 'p' or a string of zero-length is the same thing */
341 if(p && (strlen((const char *)p) < 1))
343 if(ctx->DYNAMIC_LIBNAME)
344 OPENSSL_free((void*)ctx->DYNAMIC_LIBNAME);
346 ctx->DYNAMIC_LIBNAME = BUF_strdup(p);
348 ctx->DYNAMIC_LIBNAME = NULL;
349 return (ctx->DYNAMIC_LIBNAME ? 1 : 0);
350 case DYNAMIC_CMD_NO_VCHECK:
351 ctx->no_vcheck = ((i == 0) ? 0 : 1);
354 /* a NULL 'p' or a string of zero-length is the same thing */
355 if(p && (strlen((const char *)p) < 1))
358 OPENSSL_free((void*)ctx->engine_id);
360 ctx->engine_id = BUF_strdup(p);
362 ctx->engine_id = NULL;
363 return (ctx->engine_id ? 1 : 0);
364 case DYNAMIC_CMD_LIST_ADD:
365 if((i < 0) || (i > 2))
367 ENGINEerr(ENGINE_F_DYNAMIC_CTRL,
368 ENGINE_R_INVALID_ARGUMENT);
371 ctx->list_add_value = (int)i;
373 case DYNAMIC_CMD_LOAD:
374 return dynamic_load(e, ctx);
375 case DYNAMIC_CMD_DIR_LOAD:
376 if((i < 0) || (i > 2))
378 ENGINEerr(ENGINE_F_DYNAMIC_CTRL,
379 ENGINE_R_INVALID_ARGUMENT);
382 ctx->dir_load = (int)i;
384 case DYNAMIC_CMD_DIR_ADD:
385 /* a NULL 'p' or a string of zero-length is the same thing */
386 if(!p || (strlen((const char *)p) < 1))
388 ENGINEerr(ENGINE_F_DYNAMIC_CTRL,
389 ENGINE_R_INVALID_ARGUMENT);
393 char *tmp_str = BUF_strdup(p);
396 ENGINEerr(ENGINE_F_DYNAMIC_CTRL,
397 ERR_R_MALLOC_FAILURE);
400 sk_insert(ctx->dirs, tmp_str, -1);
406 ENGINEerr(ENGINE_F_DYNAMIC_CTRL,ENGINE_R_CTRL_COMMAND_NOT_IMPLEMENTED);
410 static int int_load(dynamic_data_ctx *ctx)
413 /* Unless told not to, try a direct load */
414 if((ctx->dir_load != 2) && (DSO_load(ctx->dynamic_dso,
415 ctx->DYNAMIC_LIBNAME, NULL, 0)) != NULL)
417 /* If we're not allowed to use 'dirs' or we have none, fail */
418 if(!ctx->dir_load || ((num = sk_num(ctx->dirs)) < 1))
420 for(loop = 0; loop < num; loop++)
422 const char *s = sk_value(ctx->dirs, loop);
423 char *merge = DSO_merge(ctx->dynamic_dso, ctx->DYNAMIC_LIBNAME, s);
426 if(DSO_load(ctx->dynamic_dso, merge, NULL, 0))
428 /* Found what we're looking for */
437 static int dynamic_load(ENGINE *e, dynamic_data_ctx *ctx)
442 if(!ctx->dynamic_dso)
443 ctx->dynamic_dso = DSO_new();
444 if(!ctx->DYNAMIC_LIBNAME)
448 ctx->DYNAMIC_LIBNAME =
449 DSO_convert_filename(ctx->dynamic_dso, ctx->engine_id);
453 ENGINEerr(ENGINE_F_DYNAMIC_LOAD,
454 ENGINE_R_DSO_NOT_FOUND);
455 DSO_free(ctx->dynamic_dso);
456 ctx->dynamic_dso = NULL;
459 /* We have to find a bind function otherwise it'll always end badly */
460 if(!(ctx->bind_engine = (dynamic_bind_engine)DSO_bind_func(
461 ctx->dynamic_dso, ctx->DYNAMIC_F2)))
463 ctx->bind_engine = NULL;
464 DSO_free(ctx->dynamic_dso);
465 ctx->dynamic_dso = NULL;
466 ENGINEerr(ENGINE_F_DYNAMIC_LOAD,
467 ENGINE_R_DSO_FAILURE);
470 /* Do we perform version checking? */
473 unsigned long vcheck_res = 0;
474 /* Now we try to find a version checking function and decide how
475 * to cope with failure if/when it fails. */
476 ctx->v_check = (dynamic_v_check_fn)DSO_bind_func(
477 ctx->dynamic_dso, ctx->DYNAMIC_F1);
479 vcheck_res = ctx->v_check(OSSL_DYNAMIC_VERSION);
480 /* We fail if the version checker veto'd the load *or* if it is
481 * deferring to us (by returning its version) and we think it is
483 if(vcheck_res < OSSL_DYNAMIC_OLDEST)
486 ctx->bind_engine = NULL;
488 DSO_free(ctx->dynamic_dso);
489 ctx->dynamic_dso = NULL;
490 ENGINEerr(ENGINE_F_DYNAMIC_LOAD,
491 ENGINE_R_VERSION_INCOMPATIBILITY);
495 /* First binary copy the ENGINE structure so that we can roll back if
496 * the hand-over fails */
497 memcpy(&cpy, e, sizeof(ENGINE));
498 /* Provide the ERR, "ex_data", memory, and locking callbacks so the
499 * loaded library uses our state rather than its own. FIXME: As noted in
500 * engine.h, much of this would be simplified if each area of code
501 * provided its own "summary" structure of all related callbacks. It
502 * would also increase opaqueness. */
503 fns.static_state = ENGINE_get_static_state();
504 fns.err_fns = ERR_get_implementation();
505 fns.ex_data_fns = CRYPTO_get_ex_data_implementation();
506 CRYPTO_get_mem_functions(&fns.mem_fns.malloc_cb,
507 &fns.mem_fns.realloc_cb,
508 &fns.mem_fns.free_cb);
509 fns.lock_fns.lock_locking_cb = CRYPTO_get_locking_callback();
510 fns.lock_fns.lock_add_lock_cb = CRYPTO_get_add_lock_callback();
511 fns.lock_fns.dynlock_create_cb = CRYPTO_get_dynlock_create_callback();
512 fns.lock_fns.dynlock_lock_cb = CRYPTO_get_dynlock_lock_callback();
513 fns.lock_fns.dynlock_destroy_cb = CRYPTO_get_dynlock_destroy_callback();
514 /* Now that we've loaded the dynamic engine, make sure no "dynamic"
515 * ENGINE elements will show through. */
516 engine_set_all_null(e);
518 /* Try to bind the ENGINE onto our own ENGINE structure */
519 if(!ctx->bind_engine(e, ctx->engine_id, &fns))
521 ctx->bind_engine = NULL;
523 DSO_free(ctx->dynamic_dso);
524 ctx->dynamic_dso = NULL;
525 ENGINEerr(ENGINE_F_DYNAMIC_LOAD,ENGINE_R_INIT_FAILED);
526 /* Copy the original ENGINE structure back */
527 memcpy(e, &cpy, sizeof(ENGINE));
530 /* Do we try to add this ENGINE to the internal list too? */
531 if(ctx->list_add_value > 0)
535 /* Do we tolerate this or fail? */
536 if(ctx->list_add_value > 1)
538 /* Fail - NB: By this time, it's too late to
539 * rollback, and trying to do so allows the
540 * bind_engine() code to have created leaks. We
541 * just have to fail where we are, after the
542 * ENGINE has changed. */
543 ENGINEerr(ENGINE_F_DYNAMIC_LOAD,
544 ENGINE_R_CONFLICTING_ENGINE_ID);