openssl/crypto/engine/eng_table.c

309 lines
8.7 KiB
C

/*
* Copyright 2001-2018 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
#include "internal/cryptlib.h"
#include <openssl/evp.h>
#include <openssl/lhash.h>
#include "eng_local.h"
/* The type of the items in the table */
struct st_engine_pile {
/* The 'nid' of this algorithm/mode */
int nid;
/* ENGINEs that implement this algorithm/mode. */
STACK_OF(ENGINE) *sk;
/* The default ENGINE to perform this algorithm/mode. */
ENGINE *funct;
/*
* Zero if 'sk' is newer than the cached 'funct', non-zero otherwise
*/
int uptodate;
};
/* The type exposed in eng_local.h */
struct st_engine_table {
LHASH_OF(ENGINE_PILE) piles;
}; /* ENGINE_TABLE */
typedef struct st_engine_pile_doall {
engine_table_doall_cb *cb;
void *arg;
} ENGINE_PILE_DOALL;
/* Global flags (ENGINE_TABLE_FLAG_***). */
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 int int_table_check(ENGINE_TABLE **t, int create)
{
LHASH_OF(ENGINE_PILE) *lh;
if (*t)
return 1;
if (!create)
return 0;
if ((lh = lh_ENGINE_PILE_new(engine_pile_hash, engine_pile_cmp)) == NULL)
return 0;
*t = (ENGINE_TABLE *)lh;
return 1;
}
/*
* Privately exposed (via eng_local.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_THREAD_write_lock(global_engine_lock);
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_ENGINE_PILE_retrieve(&(*table)->piles, &tmplate);
if (!fnd) {
fnd = OPENSSL_malloc(sizeof(*fnd));
if (fnd == NULL)
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;
(void)lh_ENGINE_PILE_insert(&(*table)->piles, fnd);
if (lh_ENGINE_PILE_retrieve(&(*table)->piles, &tmplate) != fnd) {
sk_ENGINE_free(fnd->sk);
OPENSSL_free(fnd);
goto end;
}
}
/* A registration shouldn't add duplicate entries */
(void)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;
fnd->uptodate = 1;
}
nids++;
}
ret = 1;
end:
CRYPTO_THREAD_unlock(global_engine_lock);
return ret;
}
static void int_unregister_cb(ENGINE_PILE *pile, ENGINE *e)
{
int n;
/* Iterate the 'c->sk' stack removing any occurrence of 'e' */
while ((n = sk_ENGINE_find(pile->sk, e)) >= 0) {
(void)sk_ENGINE_delete(pile->sk, n);
pile->uptodate = 0;
}
if (pile->funct == e) {
engine_unlocked_finish(e, 0);
pile->funct = NULL;
}
}
IMPLEMENT_LHASH_DOALL_ARG(ENGINE_PILE, ENGINE);
void engine_table_unregister(ENGINE_TABLE **table, ENGINE *e)
{
CRYPTO_THREAD_write_lock(global_engine_lock);
if (int_table_check(table, 0))
lh_ENGINE_PILE_doall_ENGINE(&(*table)->piles, int_unregister_cb, e);
CRYPTO_THREAD_unlock(global_engine_lock);
}
static void int_cleanup_cb_doall(ENGINE_PILE *p)
{
if (!p)
return;
sk_ENGINE_free(p->sk);
if (p->funct)
engine_unlocked_finish(p->funct, 0);
OPENSSL_free(p);
}
void engine_table_cleanup(ENGINE_TABLE **table)
{
CRYPTO_THREAD_write_lock(global_engine_lock);
if (*table) {
lh_ENGINE_PILE_doall(&(*table)->piles, int_cleanup_cb_doall);
lh_ENGINE_PILE_free(&(*table)->piles);
*table = NULL;
}
CRYPTO_THREAD_unlock(global_engine_lock);
}
/* return a functional reference for a given '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 (!(*table)) {
#ifdef ENGINE_TABLE_DEBUG
fprintf(stderr, "engine_table_dbg: %s:%d, nid=%d, nothing "
"registered!\n", f, l, nid);
#endif
return NULL;
}
ERR_set_mark();
CRYPTO_THREAD_write_lock(global_engine_lock);
/*
* 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_ENGINE_PILE_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;
}
/* Try to initialise the ENGINE? */
if ((ret->funct_ref > 0) || !(table_flags & ENGINE_TABLE_FLAG_NOINIT))
initres = engine_unlocked_init(ret);
else
initres = 0;
if (initres) {
/* Update '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);
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:
/*
* If it failed, it is unlikely to succeed again until some future
* registrations have taken place. In all cases, we cache.
*/
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_THREAD_unlock(global_engine_lock);
/*
* Whatever happened, any failed init()s are not failures in this
* context, so clear our error state.
*/
ERR_pop_to_mark();
return ret;
}
/* Table enumeration */
static void int_dall(const ENGINE_PILE *pile, ENGINE_PILE_DOALL *dall)
{
dall->cb(pile->nid, pile->sk, pile->funct, dall->arg);
}
IMPLEMENT_LHASH_DOALL_ARG_CONST(ENGINE_PILE, ENGINE_PILE_DOALL);
void engine_table_doall(ENGINE_TABLE *table, engine_table_doall_cb *cb,
void *arg)
{
ENGINE_PILE_DOALL dall;
dall.cb = cb;
dall.arg = arg;
if (table)
lh_ENGINE_PILE_doall_ENGINE_PILE_DOALL(&table->piles, int_dall, &dall);
}