/*

 * Copyright 2019-2022 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the Apache License 2.0 (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 "crypto/cryptlib.h"

#include <openssl/conf.h>

#include "internal/thread_once.h"

#include "internal/property.h"

#include "internal/core.h"

#include "internal/bio.h"

#include "internal/provider.h"

#include "crypto/ctype.h"

#include "crypto/rand.h"

struct ossl_lib_ctx_onfree_list_st {

    ossl_lib_ctx_onfree_fn *fn;

    struct ossl_lib_ctx_onfree_list_st *next;

};

struct ossl_lib_ctx_st {

    CRYPTO_RWLOCK *lock;

    CRYPTO_EX_DATA data;

    /*

     * For most data in the OSSL_LIB_CTX we just use ex_data to store it. But

     * that doesn't work for ex_data itself - so we store that directly.

     */

    OSSL_EX_DATA_GLOBAL global;

    /* Map internal static indexes to dynamically created indexes */

    int dyn_indexes[OSSL_LIB_CTX_MAX_INDEXES];

    /* Keep a separate lock for each index */

    CRYPTO_RWLOCK *index_locks[OSSL_LIB_CTX_MAX_INDEXES];

    CRYPTO_RWLOCK *oncelock;

    int run_once_done[OSSL_LIB_CTX_MAX_RUN_ONCE];

    int run_once_ret[OSSL_LIB_CTX_MAX_RUN_ONCE];

    struct ossl_lib_ctx_onfree_list_st *onfreelist;

    unsigned int ischild:1;

};

int ossl_lib_ctx_write_lock(OSSL_LIB_CTX *ctx)

{

    return CRYPTO_THREAD_write_lock(ossl_lib_ctx_get_concrete(ctx)->lock);

}

int ossl_lib_ctx_read_lock(OSSL_LIB_CTX *ctx)

{

    return CRYPTO_THREAD_read_lock(ossl_lib_ctx_get_concrete(ctx)->lock);

}

int ossl_lib_ctx_unlock(OSSL_LIB_CTX *ctx)

{

    return CRYPTO_THREAD_unlock(ossl_lib_ctx_get_concrete(ctx)->lock);

}

int ossl_lib_ctx_is_child(OSSL_LIB_CTX *ctx)

{

    ctx = ossl_lib_ctx_get_concrete(ctx);

    if (ctx == NULL)

        return 0;

    return ctx->ischild;

}

static int context_init(OSSL_LIB_CTX *ctx)

{

    size_t i;

    int exdata_done = 0;

    ctx->lock = CRYPTO_THREAD_lock_new();

    if (ctx->lock == NULL)

        return 0;

    ctx->oncelock = CRYPTO_THREAD_lock_new();

    if (ctx->oncelock == NULL)

        goto err;

    for (i = 0; i < OSSL_LIB_CTX_MAX_INDEXES; i++) {

        ctx->index_locks[i] = CRYPTO_THREAD_lock_new();

        ctx->dyn_indexes[i] = -1;

        if (ctx->index_locks[i] == NULL)

            goto err;

    }

    /* OSSL_LIB_CTX is built on top of ex_data so we initialise that directly */

    if (!ossl_do_ex_data_init(ctx))

        goto err;

    exdata_done = 1;

    if (!ossl_crypto_new_ex_data_ex(ctx, CRYPTO_EX_INDEX_OSSL_LIB_CTX, NULL,

                                    &ctx->data))

        goto err;

    /* Everything depends on properties, so we also pre-initialise that */

    if (!ossl_property_parse_init(ctx))

        goto err;

    return 1;

 err:

    if (exdata_done)

        ossl_crypto_cleanup_all_ex_data_int(ctx);

    for (i = 0; i < OSSL_LIB_CTX_MAX_INDEXES; i++)

        CRYPTO_THREAD_lock_free(ctx->index_locks[i]);

    CRYPTO_THREAD_lock_free(ctx->oncelock);

    CRYPTO_THREAD_lock_free(ctx->lock);

    memset(ctx, '\0', sizeof(*ctx));

    return 0;

}

static int context_deinit(OSSL_LIB_CTX *ctx)

{

    struct ossl_lib_ctx_onfree_list_st *tmp, *onfree;

    int i;

    if (ctx == NULL)

        return 1;

    ossl_ctx_thread_stop(ctx);

    onfree = ctx->onfreelist;

    while (onfree != NULL) {

        onfree->fn(ctx);

        tmp = onfree;

        onfree = onfree->next;

        OPENSSL_free(tmp);

    }

    CRYPTO_free_ex_data(CRYPTO_EX_INDEX_OSSL_LIB_CTX, NULL, &ctx->data);

    ossl_crypto_cleanup_all_ex_data_int(ctx);

    for (i = 0; i < OSSL_LIB_CTX_MAX_INDEXES; i++)

        CRYPTO_THREAD_lock_free(ctx->index_locks[i]);

    CRYPTO_THREAD_lock_free(ctx->oncelock);

    CRYPTO_THREAD_lock_free(ctx->lock);

    ctx->lock = NULL;

    return 1;

}

#ifndef FIPS_MODULE

/* The default default context */

static OSSL_LIB_CTX default_context_int;

static CRYPTO_ONCE default_context_init = CRYPTO_ONCE_STATIC_INIT;

static CRYPTO_THREAD_LOCAL default_context_thread_local;

DEFINE_RUN_ONCE_STATIC(default_context_do_init)

{

    return CRYPTO_THREAD_init_local(&default_context_thread_local, NULL)

        && context_init(&default_context_int);

}

void ossl_lib_ctx_default_deinit(void)

{

    context_deinit(&default_context_int);

    CRYPTO_THREAD_cleanup_local(&default_context_thread_local);

}

static OSSL_LIB_CTX *get_thread_default_context(void)

{

    if (!RUN_ONCE(&default_context_init, default_context_do_init))

        return NULL;

    return CRYPTO_THREAD_get_local(&default_context_thread_local);

}

static OSSL_LIB_CTX *get_default_context(void)

{

    OSSL_LIB_CTX *current_defctx = get_thread_default_context();

    if (current_defctx == NULL)

        current_defctx = &default_context_int;

    return current_defctx;

}

static int set_default_context(OSSL_LIB_CTX *defctx)

{

    if (defctx == &default_context_int)

        defctx = NULL;

    return CRYPTO_THREAD_set_local(&default_context_thread_local, defctx);

}

#endif

OSSL_LIB_CTX *OSSL_LIB_CTX_new(void)

{

    OSSL_LIB_CTX *ctx = OPENSSL_zalloc(sizeof(*ctx));

    if (ctx != NULL && !context_init(ctx)) {

        OPENSSL_free(ctx);

        ctx = NULL;

    }

    return ctx;

}

#ifndef FIPS_MODULE

OSSL_LIB_CTX *OSSL_LIB_CTX_new_from_dispatch(const OSSL_CORE_HANDLE *handle,

                                             const OSSL_DISPATCH *in)

{

    OSSL_LIB_CTX *ctx = OSSL_LIB_CTX_new();

    if (ctx == NULL)

        return NULL;

    if (!ossl_bio_init_core(ctx, in)) {

        OSSL_LIB_CTX_free(ctx);

        return NULL;

    }

    return ctx;

}

OSSL_LIB_CTX *OSSL_LIB_CTX_new_child(const OSSL_CORE_HANDLE *handle,

                                     const OSSL_DISPATCH *in)

{

    OSSL_LIB_CTX *ctx = OSSL_LIB_CTX_new_from_dispatch(handle, in);

    if (ctx == NULL)

        return NULL;

    if (!ossl_provider_init_as_child(ctx, handle, in)) {

        OSSL_LIB_CTX_free(ctx);

        return NULL;

    }

    ctx->ischild = 1;

    return ctx;

}

int OSSL_LIB_CTX_load_config(OSSL_LIB_CTX *ctx, const char *config_file)

{

    return CONF_modules_load_file_ex(ctx, config_file, NULL, 0) > 0;

}

#endif

void OSSL_LIB_CTX_free(OSSL_LIB_CTX *ctx)

{

    if (ossl_lib_ctx_is_default(ctx))

        return;

#ifndef FIPS_MODULE

    if (ctx->ischild)

        ossl_provider_deinit_child(ctx);

#endif

    context_deinit(ctx);

    OPENSSL_free(ctx);

}

#ifndef FIPS_MODULE

OSSL_LIB_CTX *OSSL_LIB_CTX_get0_global_default(void)

{

    if (!RUN_ONCE(&default_context_init, default_context_do_init))

        return NULL;

    return &default_context_int;

}

OSSL_LIB_CTX *OSSL_LIB_CTX_set0_default(OSSL_LIB_CTX *libctx)

{

    OSSL_LIB_CTX *current_defctx;

    if ((current_defctx = get_default_context()) != NULL) {

        if (libctx != NULL)

            set_default_context(libctx);

        return current_defctx;

    }

    return NULL;

}

void ossl_release_default_drbg_ctx(void)

{

    int dynidx = default_context_int.dyn_indexes[OSSL_LIB_CTX_DRBG_INDEX];

    /* early release of the DRBG in global default libctx, no locking */

    if (dynidx != -1) {

        void *data;

        data = CRYPTO_get_ex_data(&default_context_int.data, dynidx);

        ossl_rand_ctx_free(data);

        CRYPTO_set_ex_data(&default_context_int.data, dynidx, NULL);

    }

}

#endif

OSSL_LIB_CTX *ossl_lib_ctx_get_concrete(OSSL_LIB_CTX *ctx)

{

#ifndef FIPS_MODULE

    if (ctx == NULL)

        return get_default_context();

#endif

    return ctx;

}

int ossl_lib_ctx_is_default(OSSL_LIB_CTX *ctx)

{

#ifndef FIPS_MODULE

    if (ctx == NULL || ctx == get_default_context())

        return 1;

#endif

    return 0;

}

int ossl_lib_ctx_is_global_default(OSSL_LIB_CTX *ctx)

{

#ifndef FIPS_MODULE

    if (ossl_lib_ctx_get_concrete(ctx) == &default_context_int)

        return 1;

#endif

    return 0;

}

static void ossl_lib_ctx_generic_new(void *parent_ign, void *ptr_ign,

                                     CRYPTO_EX_DATA *ad, int index,

                                     long argl_ign, void *argp)

{

    const OSSL_LIB_CTX_METHOD *meth = argp;

    OSSL_LIB_CTX *ctx = ossl_crypto_ex_data_get_ossl_lib_ctx(ad);

    void *ptr = meth->new_func(ctx);

    if (ptr != NULL) {

        if (!CRYPTO_THREAD_write_lock(ctx->lock))

            /*

             * Can't return something, so best to hope that something will

             * fail later. :(

             */

            return;

        CRYPTO_set_ex_data(ad, index, ptr);

        CRYPTO_THREAD_unlock(ctx->lock);

    }

}

static void ossl_lib_ctx_generic_free(void *parent_ign, void *ptr,

                                      CRYPTO_EX_DATA *ad, int index,

                                      long argl_ign, void *argp)

{

    const OSSL_LIB_CTX_METHOD *meth = argp;

    meth->free_func(ptr);

}

static int ossl_lib_ctx_init_index(OSSL_LIB_CTX *ctx, int static_index,

                                   const OSSL_LIB_CTX_METHOD *meth)

{

    int idx;

    ctx = ossl_lib_ctx_get_concrete(ctx);

    if (ctx == NULL)

        return 0;

    idx = ossl_crypto_get_ex_new_index_ex(ctx, CRYPTO_EX_INDEX_OSSL_LIB_CTX, 0,

                                          (void *)meth,

                                          ossl_lib_ctx_generic_new,

                                          NULL, ossl_lib_ctx_generic_free,

                                          meth->priority);

    if (idx < 0)

        return 0;

    ctx->dyn_indexes[static_index] = idx;

    return 1;

}

void *ossl_lib_ctx_get_data(OSSL_LIB_CTX *ctx, int index,

                            const OSSL_LIB_CTX_METHOD *meth)

{

    void *data = NULL;

    int dynidx;

    ctx = ossl_lib_ctx_get_concrete(ctx);

    if (ctx == NULL)

        return NULL;

    if (!CRYPTO_THREAD_read_lock(ctx->lock))

        return NULL;

    dynidx = ctx->dyn_indexes[index];

    CRYPTO_THREAD_unlock(ctx->lock);

    if (dynidx != -1) {

        if (!CRYPTO_THREAD_read_lock(ctx->index_locks[index]))

            return NULL;

        if (!CRYPTO_THREAD_read_lock(ctx->lock)) {

            CRYPTO_THREAD_unlock(ctx->index_locks[index]);

            return NULL;

        }

        data = CRYPTO_get_ex_data(&ctx->data, dynidx);

        CRYPTO_THREAD_unlock(ctx->lock);

        CRYPTO_THREAD_unlock(ctx->index_locks[index]);

        return data;

    }

    if (!CRYPTO_THREAD_write_lock(ctx->index_locks[index]))

        return NULL;

    if (!CRYPTO_THREAD_write_lock(ctx->lock)) {

        CRYPTO_THREAD_unlock(ctx->index_locks[index]);

        return NULL;

    }

    dynidx = ctx->dyn_indexes[index];

    if (dynidx != -1) {

        data = CRYPTO_get_ex_data(&ctx->data, dynidx);

        CRYPTO_THREAD_unlock(ctx->lock);

        CRYPTO_THREAD_unlock(ctx->index_locks[index]);

        return data;

    }

    if (!ossl_lib_ctx_init_index(ctx, index, meth)) {

        CRYPTO_THREAD_unlock(ctx->lock);

        CRYPTO_THREAD_unlock(ctx->index_locks[index]);

        return NULL;

    }

    CRYPTO_THREAD_unlock(ctx->lock);

    /*

     * The alloc call ensures there's a value there. We release the ctx->lock

     * for this, because the allocation itself may recursively call

     * ossl_lib_ctx_get_data for other indexes (never this one). The allocation

     * will itself aquire the ctx->lock when it actually comes to store the

     * allocated data (see ossl_lib_ctx_generic_new() above). We call

     * ossl_crypto_alloc_ex_data_intern() here instead of CRYPTO_alloc_ex_data().

     * They do the same thing except that the latter calls CRYPTO_get_ex_data()

     * as well - which we must not do without holding the ctx->lock.

     */

    if (ossl_crypto_alloc_ex_data_intern(CRYPTO_EX_INDEX_OSSL_LIB_CTX, NULL,

                                         &ctx->data, ctx->dyn_indexes[index])) {

        if (!CRYPTO_THREAD_read_lock(ctx->lock))

            goto end;

        data = CRYPTO_get_ex_data(&ctx->data, ctx->dyn_indexes[index]);

        CRYPTO_THREAD_unlock(ctx->lock);

    }

end:

    CRYPTO_THREAD_unlock(ctx->index_locks[index]);

    return data;

}

OSSL_EX_DATA_GLOBAL *ossl_lib_ctx_get_ex_data_global(OSSL_LIB_CTX *ctx)

{

    ctx = ossl_lib_ctx_get_concrete(ctx);

    if (ctx == NULL)

        return NULL;

    return &ctx->global;

}

int ossl_lib_ctx_run_once(OSSL_LIB_CTX *ctx, unsigned int idx,

                          ossl_lib_ctx_run_once_fn run_once_fn)

{

    int done = 0, ret = 0;

    ctx = ossl_lib_ctx_get_concrete(ctx);

    if (ctx == NULL)

        return 0;

    if (!CRYPTO_THREAD_read_lock(ctx->oncelock))

        return 0;

    done = ctx->run_once_done[idx];

    if (done)

        ret = ctx->run_once_ret[idx];

    CRYPTO_THREAD_unlock(ctx->oncelock);

    if (done)

        return ret;

    if (!CRYPTO_THREAD_write_lock(ctx->oncelock))

        return 0;

    if (ctx->run_once_done[idx]) {

        ret = ctx->run_once_ret[idx];

        CRYPTO_THREAD_unlock(ctx->oncelock);

        return ret;

    }

    ret = run_once_fn(ctx);

    ctx->run_once_done[idx] = 1;

    ctx->run_once_ret[idx] = ret;

    CRYPTO_THREAD_unlock(ctx->oncelock);

    return ret;

}

int ossl_lib_ctx_onfree(OSSL_LIB_CTX *ctx, ossl_lib_ctx_onfree_fn onfreefn)

{

    struct ossl_lib_ctx_onfree_list_st *newonfree

        = OPENSSL_malloc(sizeof(*newonfree));

    if (newonfree == NULL)

        return 0;

    newonfree->fn = onfreefn;

    newonfree->next = ctx->onfreelist;

    ctx->onfreelist = newonfree;

    return 1;

}

const char *ossl_lib_ctx_get_descriptor(OSSL_LIB_CTX *libctx)

{

#ifdef FIPS_MODULE

    return "FIPS internal library context";

#else

    if (ossl_lib_ctx_is_global_default(libctx))

        return "Global default library context";

    if (ossl_lib_ctx_is_default(libctx))

        return "Thread-local default library context";

    return "Non-default library context";

#endif

}