/*

 * Copyright 2019 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 "internal/thread_once.h"

#include "internal/property.h"

struct openssl_ctx_onfree_list_st {

    openssl_ctx_onfree_fn *fn;

    struct openssl_ctx_onfree_list_st *next;

};

struct openssl_ctx_st {

    CRYPTO_RWLOCK *lock;

    CRYPTO_EX_DATA data;

    /*

     * For most data in the OPENSSL_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[OPENSSL_CTX_MAX_INDEXES];

    /* Keep a separate lock for each index */

    CRYPTO_RWLOCK *index_locks[OPENSSL_CTX_MAX_INDEXES];

    CRYPTO_RWLOCK *oncelock;

    int run_once_done[OPENSSL_CTX_MAX_RUN_ONCE];

    int run_once_ret[OPENSSL_CTX_MAX_RUN_ONCE];

    struct openssl_ctx_onfree_list_st *onfreelist;

};

#ifndef FIPS_MODE

static OPENSSL_CTX default_context_int;

/* Always points at default_context_int if it has been initialised */

static OPENSSL_CTX *default_context = NULL;

#endif

static int context_init(OPENSSL_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 < OPENSSL_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;

    }

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

    if (!do_ex_data_init(ctx))

        goto err;

    exdata_done = 1;

    if (!crypto_new_ex_data_ex(ctx, CRYPTO_EX_INDEX_OPENSSL_CTX, NULL,

                               &ctx->data)) {

        crypto_cleanup_all_ex_data_int(ctx);

        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)

        crypto_cleanup_all_ex_data_int(ctx);

    CRYPTO_THREAD_lock_free(ctx->oncelock);

    CRYPTO_THREAD_lock_free(ctx->lock);

    ctx->lock = NULL;

    return 0;

}

static int context_deinit(OPENSSL_CTX *ctx)

{

    struct openssl_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_OPENSSL_CTX, NULL, &ctx->data);

    crypto_cleanup_all_ex_data_int(ctx);

    for (i = 0; i < OPENSSL_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_MODE

void openssl_ctx_default_deinit(void)

{

    context_deinit(default_context);

}

static CRYPTO_ONCE default_context_init = CRYPTO_ONCE_STATIC_INIT;

DEFINE_RUN_ONCE_STATIC(do_default_context_init)

{

    if (context_init(&default_context_int))

        default_context = &default_context_int;

    return 1;

}

#endif

OPENSSL_CTX *OPENSSL_CTX_new(void)

{

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

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

        OPENSSL_CTX_free(ctx);

        ctx = NULL;

    }

    return ctx;

}

void OPENSSL_CTX_free(OPENSSL_CTX *ctx)

{

    if (ctx != NULL)

        context_deinit(ctx);

    OPENSSL_free(ctx);

}

OPENSSL_CTX *openssl_ctx_get_concrete(OPENSSL_CTX *ctx)

{

#ifndef FIPS_MODE

    if (ctx == NULL) {

        if (!RUN_ONCE(&default_context_init, do_default_context_init))

            return 0;

        return default_context;

    }

#endif

    return ctx;

}

static void openssl_ctx_generic_new(void *parent_ign, void *ptr_ign,

                                    CRYPTO_EX_DATA *ad, int index,

                                    long argl_ign, void *argp)

{

    const OPENSSL_CTX_METHOD *meth = argp;

    void *ptr = meth->new_func(crypto_ex_data_get_openssl_ctx(ad));

    if (ptr != NULL)

        CRYPTO_set_ex_data(ad, index, ptr);

}

static void openssl_ctx_generic_free(void *parent_ign, void *ptr,

                                     CRYPTO_EX_DATA *ad, int index,

                                     long argl_ign, void *argp)

{

    const OPENSSL_CTX_METHOD *meth = argp;

    meth->free_func(ptr);

}

/* Non-static so we can use it in context_internal_test */

static int openssl_ctx_init_index(OPENSSL_CTX *ctx, int static_index,

                                  const OPENSSL_CTX_METHOD *meth)

{

    int idx;

    ctx = openssl_ctx_get_concrete(ctx);

    if (ctx == NULL)

        return 0;

    idx = crypto_get_ex_new_index_ex(ctx, CRYPTO_EX_INDEX_OPENSSL_CTX, 0,

                                     (void *)meth,

                                     openssl_ctx_generic_new,

                                     NULL, openssl_ctx_generic_free);

    if (idx < 0)

        return 0;

    ctx->dyn_indexes[static_index] = idx;

    return 1;

}

void *openssl_ctx_get_data(OPENSSL_CTX *ctx, int index,

                           const OPENSSL_CTX_METHOD *meth)

{

    void *data = NULL;

    int dynidx;

    ctx = openssl_ctx_get_concrete(ctx);

    if (ctx == NULL)

        return NULL;

    CRYPTO_THREAD_read_lock(ctx->lock);

    dynidx = ctx->dyn_indexes[index];

    CRYPTO_THREAD_unlock(ctx->lock);

    if (dynidx != -1) {

        CRYPTO_THREAD_read_lock(ctx->index_locks[index]);

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

        CRYPTO_THREAD_unlock(ctx->index_locks[index]);

        return data;

    }

    CRYPTO_THREAD_write_lock(ctx->index_locks[index]);

    CRYPTO_THREAD_write_lock(ctx->lock);

    dynidx = ctx->dyn_indexes[index];

    if (dynidx != -1) {

        CRYPTO_THREAD_unlock(ctx->lock);

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

        CRYPTO_THREAD_unlock(ctx->index_locks[index]);

        return data;

    }

    if (!openssl_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 */

    if (CRYPTO_alloc_ex_data(CRYPTO_EX_INDEX_OPENSSL_CTX, NULL,

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

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

    CRYPTO_THREAD_unlock(ctx->index_locks[index]);

    return data;

}

OSSL_EX_DATA_GLOBAL *openssl_ctx_get_ex_data_global(OPENSSL_CTX *ctx)

{

    ctx = openssl_ctx_get_concrete(ctx);

    if (ctx == NULL)

        return NULL;

    return &ctx->global;

}

int openssl_ctx_run_once(OPENSSL_CTX *ctx, unsigned int idx,

                         openssl_ctx_run_once_fn run_once_fn)

{

    int done = 0, ret = 0;

    ctx = openssl_ctx_get_concrete(ctx);

    if (ctx == NULL)

        return 0;

    CRYPTO_THREAD_read_lock(ctx->oncelock);

    done = ctx->run_once_done[idx];

    if (done)

        ret = ctx->run_once_ret[idx];

    CRYPTO_THREAD_unlock(ctx->oncelock);

    if (done)

        return ret;

    CRYPTO_THREAD_write_lock(ctx->oncelock);

    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 openssl_ctx_onfree(OPENSSL_CTX *ctx, openssl_ctx_onfree_fn onfreefn)

{

    struct openssl_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;

}