/* ==================================================================== * Copyright (c) 2001 The OpenSSL Project. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * 3. All advertising materials mentioning features or use of this * software must display the following acknowledgment: * "This product includes software developed by the OpenSSL Project * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)" * * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to * endorse or promote products derived from this software without * prior written permission. For written permission, please contact * licensing@OpenSSL.org. * * 5. Products derived from this software may not be called "OpenSSL" * nor may "OpenSSL" appear in their names without prior written * permission of the OpenSSL Project. * * 6. Redistributions of any form whatsoever must retain the following * acknowledgment: * "This product includes software developed by the OpenSSL Project * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)" * * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED * OF THE POSSIBILITY OF SUCH DAMAGE. * ==================================================================== * * This product includes cryptographic software written by Eric Young * (eay@cryptsoft.com). This product includes software written by Tim * Hudson (tjh@cryptsoft.com). * */ #include <openssl/evp.h> #include <openssl/engine.h> #include "eng_int.h" /* This is the type of item in the 'implementation' table. Each 'nid' hashes to * a (potentially NULL) ENGINE_PILE structure which contains a stack of ENGINE* * pointers. These pointers aren't references, because they're inserted and * removed during ENGINE creation and ENGINE destruction. They point to ENGINEs * that *exist* (ie. have a structural reference count greater than zero) rather * than ENGINEs that are *functional*. Each pointer in those stacks are to * ENGINEs that implements the algorithm corresponding to each 'nid'. */ /* The type of the items in the table */ typedef struct st_engine_pile { /* The 'nid' of the algorithm/mode this ENGINE_PILE structure represents * */ int nid; /* A stack of ENGINE pointers for ENGINEs that support this * algorithm/mode. In the event that 'funct' is NULL, the first entry in * this stack that initialises will be set as 'funct' and assumed as the * default for operations of this type. */ STACK_OF(ENGINE) *sk; /* The default ENGINE to perform this algorithm/mode. */ ENGINE *funct; /* This value optimises engine_table_select(). If it is called it sets * this value to 1. Any changes to this ENGINE_PILE resets it to zero. * As such, no ENGINE_init() thrashing is done unless ENGINEs * continually register (and/or unregister). */ int uptodate; } ENGINE_PILE; /* The type of the hash table of ENGINE_PILE structures such that each are * unique and keyed by the 'nid' value. */ struct st_engine_table { LHASH piles; }; /* ENGINE_TABLE */ /* This value stores global options controlling behaviour of (mostly) the * engine_table_select() function. It's a bitmask of flag values of the form * ENGINE_TABLE_FLAG_*** (as defined in engine.h) and is controlled by the * ENGINE_[get|set]_table_flags() function. */ static unsigned int table_flags = 0; /* API function manipulating 'table_flags' */ unsigned int ENGINE_get_table_flags(void) { return table_flags; } void ENGINE_set_table_flags(unsigned int flags) { table_flags = flags; } /* Internal functions for the "piles" hash table */ static unsigned long engine_pile_hash(const ENGINE_PILE *c) { return c->nid; } static int engine_pile_cmp(const ENGINE_PILE *a, const ENGINE_PILE *b) { return a->nid - b->nid; } static IMPLEMENT_LHASH_HASH_FN(engine_pile_hash, const ENGINE_PILE *) static IMPLEMENT_LHASH_COMP_FN(engine_pile_cmp, const ENGINE_PILE *) static int int_table_check(ENGINE_TABLE **t, int create) { LHASH *lh; if(*t) return 1; if(!create) return 0; if((lh = lh_new(LHASH_HASH_FN(engine_pile_hash), LHASH_COMP_FN(engine_pile_cmp))) == NULL) return 0; *t = (ENGINE_TABLE *)lh; return 1; } /* Privately exposed (via eng_int.h) functions for adding and/or removing * ENGINEs from the implementation table */ int engine_table_register(ENGINE_TABLE **table, ENGINE_CLEANUP_CB *cleanup, ENGINE *e, const int *nids, int num_nids, int setdefault) { int ret = 0, added = 0; ENGINE_PILE tmplate, *fnd; CRYPTO_w_lock(CRYPTO_LOCK_ENGINE); if(!(*table)) added = 1; if(!int_table_check(table, 1)) goto end; if(added) /* The cleanup callback needs to be added */ engine_cleanup_add_first(cleanup); while(num_nids--) { tmplate.nid = *nids; fnd = lh_retrieve(&(*table)->piles, &tmplate); if(!fnd) { fnd = OPENSSL_malloc(sizeof(ENGINE_PILE)); if(!fnd) goto end; fnd->uptodate = 1; fnd->nid = *nids; fnd->sk = sk_ENGINE_new_null(); if(!fnd->sk) { OPENSSL_free(fnd); goto end; } fnd->funct= NULL; lh_insert(&(*table)->piles, fnd); } /* A registration shouldn't add duplciate entries */ sk_ENGINE_delete_ptr(fnd->sk, e); /* if 'setdefault', this ENGINE goes to the head of the list */ if(!sk_ENGINE_push(fnd->sk, e)) goto end; /* "touch" this ENGINE_PILE */ fnd->uptodate = 0; if(setdefault) { if(!engine_unlocked_init(e)) { ENGINEerr(ENGINE_F_ENGINE_TABLE_REGISTER, ENGINE_R_INIT_FAILED); goto end; } if(fnd->funct) engine_unlocked_finish(fnd->funct, 0); fnd->funct = e; } nids++; } ret = 1; end: CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE); return ret; } static void int_unregister_cb(ENGINE_PILE *pile, ENGINE *e) { int n; /* Iterate the 'c->sk' stack removing any occurance of 'e' */ while((n = sk_ENGINE_find(pile->sk, e)) >= 0) { sk_ENGINE_delete(pile->sk, n); /* "touch" this ENGINE_CIPHER */ pile->uptodate = 0; } if(pile->funct == e) { engine_unlocked_finish(e, 0); pile->funct = NULL; } } static IMPLEMENT_LHASH_DOALL_ARG_FN(int_unregister_cb,ENGINE_PILE *,ENGINE *) void engine_table_unregister(ENGINE_TABLE **table, ENGINE *e) { CRYPTO_w_lock(CRYPTO_LOCK_ENGINE); if(int_table_check(table, 0)) lh_doall_arg(&(*table)->piles, LHASH_DOALL_ARG_FN(int_unregister_cb), e); CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE); } static void int_cleanup_cb(ENGINE_PILE *p) { sk_ENGINE_free(p->sk); if(p->funct) engine_unlocked_finish(p->funct, 0); OPENSSL_free(p); } static IMPLEMENT_LHASH_DOALL_FN(int_cleanup_cb,ENGINE_PILE *) void engine_table_cleanup(ENGINE_TABLE **table) { CRYPTO_w_lock(CRYPTO_LOCK_ENGINE); if(*table) { lh_doall(&(*table)->piles, LHASH_DOALL_FN(int_cleanup_cb)); lh_free(&(*table)->piles); *table = NULL; } CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE); } /* Exposed API function to get a functional reference from the implementation * table (ie. try to get a functional reference from the tabled structural * references) for a given cipher 'nid' */ #ifndef ENGINE_TABLE_DEBUG ENGINE *engine_table_select(ENGINE_TABLE **table, int nid) #else ENGINE *engine_table_select_tmp(ENGINE_TABLE **table, int nid, const char *f, int l) #endif { ENGINE *ret = NULL; ENGINE_PILE tmplate, *fnd=NULL; int initres, loop = 0; /* If 'engine_ciphers' is NULL, then it's absolutely *sure* that no * ENGINEs have registered any implementations! */ if(!(*table)) { #ifdef ENGINE_TABLE_DEBUG fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, no " "registered for anything!\n", f, l, nid); #endif return NULL; } CRYPTO_w_lock(CRYPTO_LOCK_ENGINE); /* Check again inside the lock otherwise we could race against cleanup * operations. But don't worry about a fprintf(stderr). */ if(!int_table_check(table, 0)) goto end; tmplate.nid = nid; fnd = lh_retrieve(&(*table)->piles, &tmplate); if(!fnd) goto end; if(fnd->funct && engine_unlocked_init(fnd->funct)) { #ifdef ENGINE_TABLE_DEBUG fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, using " "ENGINE '%s' cached\n", f, l, nid, fnd->funct->id); #endif ret = fnd->funct; goto end; } if(fnd->uptodate) { ret = fnd->funct; goto end; } trynext: ret = sk_ENGINE_value(fnd->sk, loop++); if(!ret) { #ifdef ENGINE_TABLE_DEBUG fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, no " "registered implementations would initialise\n", f, l, nid); #endif goto end; } #if 0 /* Don't need to get a reference if we hold the lock. If the locking has * to change in future, that would be different ... */ ret->struct_ref++; engine_ref_debug(ret, 0, 1) #endif /* Try and initialise the ENGINE if it's already functional *or* if the * ENGINE_TABLE_FLAG_NOINIT flag is not set. */ if((ret->funct_ref > 0) || !(table_flags & ENGINE_TABLE_FLAG_NOINIT)) initres = engine_unlocked_init(ret); else initres = 0; #if 0 /* Release the structural reference */ ret->struct_ref--; engine_ref_debug(ret, 0, -1); #endif if(initres) { /* If we didn't have a default (functional reference) for this * 'nid' (or we had one but for whatever reason we're now * initialising a different one), use this opportunity to set * 'funct'. */ if((fnd->funct != ret) && engine_unlocked_init(ret)) { /* If there was a previous default we release it. */ if(fnd->funct) engine_unlocked_finish(fnd->funct, 0); /* We got an extra functional reference for the * per-'nid' default */ fnd->funct = ret; #ifdef ENGINE_TABLE_DEBUG fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, " "setting default to '%s'\n", f, l, nid, ret->id); #endif } #ifdef ENGINE_TABLE_DEBUG fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, using " "newly initialised '%s'\n", f, l, nid, ret->id); #endif goto end; } goto trynext; end: /* Whatever happened - we should "untouch" our uptodate file seeing as * we have tried our best to find a functional reference for 'nid'. If * it failed, it is unlikely to succeed again until some future * registrations (or unregistrations) have taken place that affect that * 'nid'. */ if(fnd) fnd->uptodate = 1; #ifdef ENGINE_TABLE_DEBUG if(ret) fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, caching " "ENGINE '%s'\n", f, l, nid, ret->id); else fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, caching " "'no matching ENGINE'\n", f, l, nid); #endif CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE); /* Whatever happened, any failed init()s are not failures in this * context, so clear our error state. */ ERR_clear_error(); return ret; }