/*

 * Copyright 1998-2022 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 <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <openssl/err.h>

#include <openssl/lhash.h>

#include <openssl/objects.h>

#include <openssl/safestack.h>

#include <openssl/e_os2.h>

#include "internal/thread_once.h"

#include "crypto/lhash.h"

#include "obj_local.h"

#include "internal/e_os.h"

/*

 * I use the ex_data stuff to manage the identifiers for the obj_name_types

 * that applications may define.  I only really use the free function field.

 */

static LHASH_OF(OBJ_NAME) *names_lh = NULL;

static int names_type_num = OBJ_NAME_TYPE_NUM;

static CRYPTO_RWLOCK *obj_lock = NULL;

struct name_funcs_st {

    unsigned long (*hash_func) (const char *name);

    int (*cmp_func) (const char *a, const char *b);

    void (*free_func) (const char *, int, const char *);

};

static STACK_OF(NAME_FUNCS) *name_funcs_stack;

/*

 * The LHASH callbacks now use the raw "void *" prototypes and do

 * per-variable casting in the functions. This prevents function pointer

 * casting without the need for macro-generated wrapper functions.

 */

static unsigned long obj_name_hash(const OBJ_NAME *a);

static int obj_name_cmp(const OBJ_NAME *a, const OBJ_NAME *b);

static CRYPTO_ONCE init = CRYPTO_ONCE_STATIC_INIT;

DEFINE_RUN_ONCE_STATIC(o_names_init)

{

    names_lh = NULL;

    obj_lock = CRYPTO_THREAD_lock_new();

    if (obj_lock != NULL)

        names_lh = lh_OBJ_NAME_new(obj_name_hash, obj_name_cmp);

    if (names_lh == NULL) {

        CRYPTO_THREAD_lock_free(obj_lock);

        obj_lock = NULL;

    }

    return names_lh != NULL && obj_lock != NULL;

}

int OBJ_NAME_init(void)

{

    return RUN_ONCE(&init, o_names_init);

}

int OBJ_NAME_new_index(unsigned long (*hash_func) (const char *),

                       int (*cmp_func) (const char *, const char *),

                       void (*free_func) (const char *, int, const char *))

{

    int ret = 0, i, push;

    NAME_FUNCS *name_funcs;

    if (!OBJ_NAME_init())

        return 0;

    if (!CRYPTO_THREAD_write_lock(obj_lock))

        return 0;

    if (name_funcs_stack == NULL)

        name_funcs_stack = sk_NAME_FUNCS_new_null();

    if (name_funcs_stack == NULL) {

        /* ERROR */

        goto out;

    }

    ret = names_type_num;

    names_type_num++;

    for (i = sk_NAME_FUNCS_num(name_funcs_stack); i < names_type_num; i++) {

        name_funcs = OPENSSL_zalloc(sizeof(*name_funcs));

        if (name_funcs == NULL) {

            ret = 0;

            goto out;

        }

        name_funcs->hash_func = ossl_lh_strcasehash;

        name_funcs->cmp_func = OPENSSL_strcasecmp;

        push = sk_NAME_FUNCS_push(name_funcs_stack, name_funcs);

        if (!push) {

            ERR_raise(ERR_LIB_OBJ, ERR_R_CRYPTO_LIB);

            OPENSSL_free(name_funcs);

            ret = 0;

            goto out;

        }

    }

    name_funcs = sk_NAME_FUNCS_value(name_funcs_stack, ret);

    if (hash_func != NULL)

        name_funcs->hash_func = hash_func;

    if (cmp_func != NULL)

        name_funcs->cmp_func = cmp_func;

    if (free_func != NULL)

        name_funcs->free_func = free_func;

out:

    CRYPTO_THREAD_unlock(obj_lock);

    return ret;

}

static int obj_name_cmp(const OBJ_NAME *a, const OBJ_NAME *b)

{

    int ret;

    ret = a->type - b->type;

    if (ret == 0) {

        if ((name_funcs_stack != NULL)

            && (sk_NAME_FUNCS_num(name_funcs_stack) > a->type)) {

            ret = sk_NAME_FUNCS_value(name_funcs_stack,

                                      a->type)->cmp_func(a->name, b->name);

        } else

            ret = OPENSSL_strcasecmp(a->name, b->name);

    }

    return ret;

}

static unsigned long obj_name_hash(const OBJ_NAME *a)

{

    unsigned long ret;

    if ((name_funcs_stack != NULL)

        && (sk_NAME_FUNCS_num(name_funcs_stack) > a->type)) {

        ret =

            sk_NAME_FUNCS_value(name_funcs_stack,

                                a->type)->hash_func(a->name);

    } else {

        ret = ossl_lh_strcasehash(a->name);

    }

    ret ^= a->type;

    return ret;

}

const char *OBJ_NAME_get(const char *name, int type)

{

    OBJ_NAME on, *ret;

    int num = 0, alias;

    const char *value = NULL;

    if (name == NULL)

        return NULL;

    if (!OBJ_NAME_init())

        return NULL;

    if (!CRYPTO_THREAD_read_lock(obj_lock))

        return NULL;

    alias = type & OBJ_NAME_ALIAS;

    type &= ~OBJ_NAME_ALIAS;

    on.name = name;

    on.type = type;

    for (;;) {

        ret = lh_OBJ_NAME_retrieve(names_lh, &on);

        if (ret == NULL)

            break;

        if ((ret->alias) && !alias) {

            if (++num > 10)

                break;

            on.name = ret->data;

        } else {

            value = ret->data;

            break;

        }

    }

    CRYPTO_THREAD_unlock(obj_lock);

    return value;

}

int OBJ_NAME_add(const char *name, int type, const char *data)

{

    OBJ_NAME *onp, *ret;

    int alias, ok = 0;

    if (!OBJ_NAME_init())

        return 0;

    alias = type & OBJ_NAME_ALIAS;

    type &= ~OBJ_NAME_ALIAS;

    onp = OPENSSL_malloc(sizeof(*onp));

    if (onp == NULL)

        return 0;

    onp->name = name;

    onp->alias = alias;

    onp->type = type;

    onp->data = data;

    if (!CRYPTO_THREAD_write_lock(obj_lock)) {

        OPENSSL_free(onp);

        return 0;

    }

    ret = lh_OBJ_NAME_insert(names_lh, onp);

    if (ret != NULL) {

        /* free things */

        if ((name_funcs_stack != NULL)

            && (sk_NAME_FUNCS_num(name_funcs_stack) > ret->type)) {

            /*

             * XXX: I'm not sure I understand why the free function should

             * get three arguments... -- Richard Levitte

             */

            sk_NAME_FUNCS_value(name_funcs_stack,

                                ret->type)->free_func(ret->name, ret->type,

                                                      ret->data);

        }

        OPENSSL_free(ret);

    } else {

        if (lh_OBJ_NAME_error(names_lh)) {

            /* ERROR */

            OPENSSL_free(onp);

            goto unlock;

        }

    }

    ok = 1;

unlock:

    CRYPTO_THREAD_unlock(obj_lock);

    return ok;

}

int OBJ_NAME_remove(const char *name, int type)

{

    OBJ_NAME on, *ret;

    int ok = 0;

    if (!OBJ_NAME_init())

        return 0;

    if (!CRYPTO_THREAD_write_lock(obj_lock))

        return 0;

    type &= ~OBJ_NAME_ALIAS;

    on.name = name;

    on.type = type;

    ret = lh_OBJ_NAME_delete(names_lh, &on);

    if (ret != NULL) {

        /* free things */

        if ((name_funcs_stack != NULL)

            && (sk_NAME_FUNCS_num(name_funcs_stack) > ret->type)) {

            /*

             * XXX: I'm not sure I understand why the free function should

             * get three arguments... -- Richard Levitte

             */

            sk_NAME_FUNCS_value(name_funcs_stack,

                                ret->type)->free_func(ret->name, ret->type,

                                                      ret->data);

        }

        OPENSSL_free(ret);

        ok = 1;

    }

    CRYPTO_THREAD_unlock(obj_lock);

    return ok;

}

typedef struct {

    int type;

    void (*fn) (const OBJ_NAME *, void *arg);

    void *arg;

} OBJ_DOALL;

static void do_all_fn(const OBJ_NAME *name, OBJ_DOALL *d)

{

    if (name->type == d->type)

        d->fn(name, d->arg);

}

IMPLEMENT_LHASH_DOALL_ARG_CONST(OBJ_NAME, OBJ_DOALL);

void OBJ_NAME_do_all(int type, void (*fn) (const OBJ_NAME *, void *arg),

                     void *arg)

{

    OBJ_DOALL d;

    d.type = type;

    d.fn = fn;

    d.arg = arg;

    lh_OBJ_NAME_doall_OBJ_DOALL(names_lh, do_all_fn, &d);

}

struct doall_sorted {

    int type;

    int n;

    const OBJ_NAME **names;

};

static void do_all_sorted_fn(const OBJ_NAME *name, void *d_)

{

    struct doall_sorted *d = d_;

    if (name->type != d->type)

        return;

    d->names[d->n++] = name;

}

static int do_all_sorted_cmp(const void *n1_, const void *n2_)

{

    const OBJ_NAME *const *n1 = n1_;

    const OBJ_NAME *const *n2 = n2_;

    return strcmp((*n1)->name, (*n2)->name);

}

void OBJ_NAME_do_all_sorted(int type,

                            void (*fn) (const OBJ_NAME *, void *arg),

                            void *arg)

{

    struct doall_sorted d;

    int n;

    d.type = type;

    d.names =

        OPENSSL_malloc(sizeof(*d.names) * lh_OBJ_NAME_num_items(names_lh));

    /* Really should return an error if !d.names...but its a void function! */

    if (d.names != NULL) {

        d.n = 0;

        OBJ_NAME_do_all(type, do_all_sorted_fn, &d);

        qsort((void *)d.names, d.n, sizeof(*d.names), do_all_sorted_cmp);

        for (n = 0; n < d.n; ++n)

            fn(d.names[n], arg);

        OPENSSL_free((void *)d.names);

    }

}

static int free_type;

static void names_lh_free_doall(OBJ_NAME *onp)

{

    if (onp == NULL)

        return;

    if (free_type < 0 || free_type == onp->type)

        OBJ_NAME_remove(onp->name, onp->type);

}

static void name_funcs_free(NAME_FUNCS *ptr)

{

    OPENSSL_free(ptr);

}

void OBJ_NAME_cleanup(int type)

{

    unsigned long down_load;

    if (names_lh == NULL)

        return;

    free_type = type;

    down_load = lh_OBJ_NAME_get_down_load(names_lh);

    lh_OBJ_NAME_set_down_load(names_lh, 0);

    lh_OBJ_NAME_doall(names_lh, names_lh_free_doall);

    if (type < 0) {

        lh_OBJ_NAME_free(names_lh);

        sk_NAME_FUNCS_pop_free(name_funcs_stack, name_funcs_free);

        CRYPTO_THREAD_lock_free(obj_lock);

        names_lh = NULL;

        name_funcs_stack = NULL;

        obj_lock = NULL;

    } else

        lh_OBJ_NAME_set_down_load(names_lh, down_load);

}