lib/dns/openssl_link.c

	openssl_link.c revision 0c27b3fe77ac1d5094ba3521e8142d9e7973133f
/*
 * Portions Copyright (C) 1999-2012, 2014-2016  Internet Systems Consortium, Inc. ("ISC")
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 *
 * Portions Copyright (C) 1995-2000 by Network Associates, Inc.
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC AND NETWORK ASSOCIATES DISCLAIMS
 * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE
 * FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR
 * IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

/*
 * Principal Author: Brian Wellington
 * $Id$
 */
#ifdef OPENSSL

#include <config.h>

#include <isc/entropy.h>
#include <isc/mem.h>
#include <isc/mutex.h>
#include <isc/mutexblock.h>
#include <isc/string.h>
#include <isc/thread.h>
#include <isc/util.h>

#include <dns/log.h>

#include <dst/result.h>

#include "dst_internal.h"
#include "dst_openssl.h"

#ifdef USE_ENGINE
#include <openssl/engine.h>
#endif

static RAND_METHOD *rm = NULL;

static isc_mutex_t *locks = NULL;
static int nlocks;

#ifdef USE_ENGINE
static ENGINE *e = NULL;
#endif

static int
entropy_get(unsigned char *buf, int num) {
    isc_result_t result;
    if (num < 0)
        return (-1);
    result = dst__entropy_getdata(buf, (unsigned int) num, ISC_FALSE);
    return (result == ISC_R_SUCCESS ? 1 : -1);
}

static int
entropy_status(void) {
    return (dst__entropy_status() > 32);
}

static int
entropy_getpseudo(unsigned char *buf, int num) {
    isc_result_t result;
    if (num < 0)
        return (-1);
    result = dst__entropy_getdata(buf, (unsigned int) num, ISC_TRUE);
    return (result == ISC_R_SUCCESS ? 1 : -1);
}

#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
static void
entropy_add(const void *buf, int num, double entropy) {
    /*
     * Do nothing.  The only call to this provides no useful data anyway.
     */
    UNUSED(buf);
    UNUSED(num);
    UNUSED(entropy);
}
#else
static int
entropy_add(const void *buf, int num, double entropy) {
    /*
     * Do nothing.  The only call to this provides no useful data anyway.
     */
    UNUSED(buf);
    UNUSED(num);
    UNUSED(entropy);
    return (1);
}
#endif

static void
lock_callback(int mode, int type, const char *file, int line) {
    UNUSED(file);
    UNUSED(line);
    if ((mode & CRYPTO_LOCK) != 0)
        LOCK(&locks[type]);
    else
        UNLOCK(&locks[type]);
}

#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
static unsigned long
id_callback(void) {
    return ((unsigned long)isc_thread_self());
}
#endif

static void *
mem_alloc(size_t size) {
#ifdef OPENSSL_LEAKS
    void *ptr;

    INSIST(dst__memory_pool != NULL);
    ptr = isc_mem_allocate(dst__memory_pool, size);
    return (ptr);
#else
    INSIST(dst__memory_pool != NULL);
    return (isc_mem_allocate(dst__memory_pool, size));
#endif
}

static void
mem_free(void *ptr) {
    INSIST(dst__memory_pool != NULL);
    if (ptr != NULL)
        isc_mem_free(dst__memory_pool, ptr);
}

static void *
mem_realloc(void *ptr, size_t size) {
#ifdef OPENSSL_LEAKS
    void *rptr;

    INSIST(dst__memory_pool != NULL);
    rptr = isc_mem_reallocate(dst__memory_pool, ptr, size);
    return (rptr);
#else
    INSIST(dst__memory_pool != NULL);
    return (isc_mem_reallocate(dst__memory_pool, ptr, size));
#endif
}

isc_result_t
dst__openssl_init(const char *engine) {
    isc_result_t result;
#ifdef USE_ENGINE
    ENGINE *re;
#else

    UNUSED(engine);
#endif

#ifdef  DNS_CRYPTO_LEAKS
    CRYPTO_malloc_debug_init();
    CRYPTO_set_mem_debug_options(V_CRYPTO_MDEBUG_ALL);
    CRYPTO_mem_ctrl(CRYPTO_MEM_CHECK_ON);
#endif
    CRYPTO_set_mem_functions(mem_alloc, mem_realloc, mem_free);
    nlocks = CRYPTO_num_locks();
    locks = mem_alloc(sizeof(isc_mutex_t) * nlocks);
    if (locks == NULL)
        return (ISC_R_NOMEMORY);
    result = isc_mutexblock_init(locks, nlocks);
    if (result != ISC_R_SUCCESS)
        goto cleanup_mutexalloc;
    CRYPTO_set_locking_callback(lock_callback);
#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
    CRYPTO_set_id_callback(id_callback);
#endif

    ERR_load_crypto_strings();

    rm = mem_alloc(sizeof(RAND_METHOD));
    if (rm == NULL) {
        result = ISC_R_NOMEMORY;
        goto cleanup_mutexinit;
    }
    rm->seed = NULL;
    rm->bytes = entropy_get;
    rm->cleanup = NULL;
    rm->add = entropy_add;
    rm->pseudorand = entropy_getpseudo;
    rm->status = entropy_status;

#ifdef USE_ENGINE
#if !defined(CONF_MFLAGS_DEFAULT_SECTION)
    OPENSSL_config(NULL);
#else
    /*
     * OPENSSL_config() can only be called a single time as of
     * 1.0.2e so do the steps individually.
     */
    OPENSSL_load_builtin_modules();
    ENGINE_load_builtin_engines();
    ERR_clear_error();
    CONF_modules_load_file(NULL, NULL,
                   CONF_MFLAGS_DEFAULT_SECTION |
                   CONF_MFLAGS_IGNORE_MISSING_FILE);
#endif

    if (engine != NULL && *engine == '\0')
        engine = NULL;

    if (engine != NULL) {
        e = ENGINE_by_id(engine);
        if (e == NULL) {
            result = DST_R_NOENGINE;
            goto cleanup_rm;
        }
        /* This will init the engine. */
        if (!ENGINE_set_default(e, ENGINE_METHOD_ALL)) {
            result = DST_R_NOENGINE;
            goto cleanup_rm;
        }
    }

    re = ENGINE_get_default_RAND();
    if (re == NULL) {
        re = ENGINE_new();
        if (re == NULL) {
            result = ISC_R_NOMEMORY;
            goto cleanup_rm;
        }
        ENGINE_set_RAND(re, rm);
        ENGINE_set_default_RAND(re);
        ENGINE_free(re);
    } else
        ENGINE_finish(re);
#else
    RAND_set_rand_method(rm);
#endif /* USE_ENGINE */
    return (ISC_R_SUCCESS);

#ifdef USE_ENGINE
 cleanup_rm:
    if (e != NULL)
        ENGINE_free(e);
    e = NULL;
    mem_free(rm);
    rm = NULL;
#endif
 cleanup_mutexinit:
    CRYPTO_set_locking_callback(NULL);
    DESTROYMUTEXBLOCK(locks, nlocks);
 cleanup_mutexalloc:
    mem_free(locks);
    locks = NULL;
    return (result);
}

void
dst__openssl_destroy(void) {
    /*
     * Sequence taken from apps_shutdown() in <apps/apps.h>.
     */
    if (rm != NULL) {
#if OPENSSL_VERSION_NUMBER >= 0x00907000L
        RAND_cleanup();
#endif
        mem_free(rm);
        rm = NULL;
    }
#if (OPENSSL_VERSION_NUMBER >= 0x00907000L)
    CONF_modules_free();
#endif
    OBJ_cleanup();
    EVP_cleanup();
#if defined(USE_ENGINE)
    if (e != NULL)
        ENGINE_free(e);
    e = NULL;
#if defined(USE_ENGINE) && OPENSSL_VERSION_NUMBER >= 0x00907000L
    ENGINE_cleanup();
#endif
#endif
#if (OPENSSL_VERSION_NUMBER >= 0x00907000L)
    CRYPTO_cleanup_all_ex_data();
#endif
    ERR_clear_error();
#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
    ERR_remove_state(0);
#endif
    ERR_free_strings();

#ifdef  DNS_CRYPTO_LEAKS
    CRYPTO_mem_leaks_fp(stderr);
#endif

    if (locks != NULL) {
        CRYPTO_set_locking_callback(NULL);
        DESTROYMUTEXBLOCK(locks, nlocks);
        mem_free(locks);
        locks = NULL;
    }
}

static isc_result_t
toresult(isc_result_t fallback) {
    isc_result_t result = fallback;
    unsigned long err = ERR_get_error();
#ifdef HAVE_OPENSSL_ECDSA
    int lib = ERR_GET_LIB(err);
#endif
    int reason = ERR_GET_REASON(err);

    switch (reason) {
    /*
     * ERR_* errors are globally unique; others
     * are unique per sublibrary
     */
    case ERR_R_MALLOC_FAILURE:
        result = ISC_R_NOMEMORY;
        break;
    default:
#ifdef HAVE_OPENSSL_ECDSA
        if (lib == ERR_R_ECDSA_LIB &&
            reason == ECDSA_R_RANDOM_NUMBER_GENERATION_FAILED) {
            result = ISC_R_NOENTROPY;
            break;
        }
#endif
        break;
    }

    return (result);
}

isc_result_t
dst__openssl_toresult(isc_result_t fallback) {
    isc_result_t result;

    result = toresult(fallback);

    ERR_clear_error();
    return (result);
}

isc_result_t
dst__openssl_toresult2(const char *funcname, isc_result_t fallback) {
    return (dst__openssl_toresult3(DNS_LOGCATEGORY_GENERAL,
                       funcname, fallback));
}

isc_result_t
dst__openssl_toresult3(isc_logcategory_t *category,
               const char *funcname, isc_result_t fallback) {
    isc_result_t result;
    unsigned long err;
    const char *file, *data;
    int line, flags;
    char buf[256];

    result = toresult(fallback);

    isc_log_write(dns_lctx, category,
              DNS_LOGMODULE_CRYPTO, ISC_LOG_WARNING,
              "%s failed (%s)", funcname,
              isc_result_totext(result));

    if (result == ISC_R_NOMEMORY)
        goto done;

    for (;;) {
        err = ERR_get_error_line_data(&file, &line, &data, &flags);
        if (err == 0U)
            goto done;
        ERR_error_string_n(err, buf, sizeof(buf));
        isc_log_write(dns_lctx, category,
                  DNS_LOGMODULE_CRYPTO, ISC_LOG_INFO,
                  "%s:%s:%d:%s", buf, file, line,
                  (flags & ERR_TXT_STRING) ? data : "");
    }

    done:
    ERR_clear_error();
    return (result);
}

#if defined(USE_ENGINE)
ENGINE *
dst__openssl_getengine(const char *engine) {

    if (engine == NULL)
        return (NULL);
    if (e == NULL)
        return (NULL);
    if (strcmp(engine, ENGINE_get_id(e)) == 0)
        return (e);
    return (NULL);
}
#endif

#else /* OPENSSL */

#include <isc/util.h>

EMPTY_TRANSLATION_UNIT

#endif /* OPENSSL */
/*! \file */