/*
 * Copyright 2018-2025 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
 */
/* clang-format off */

/* clang-format on */

#include <string.h>
#include <openssl/core_dispatch.h>
#include <openssl/core_names.h>
#include <openssl/params.h>
#include <openssl/evp.h>
#include <openssl/err.h>
#include <openssl/proverr.h>

#include "internal/cryptlib.h"
#include "crypto/siphash.h"

#include "prov/implementations.h"
#include "prov/providercommon.h"

/*
 * Forward declaration of everything implemented here.  This is not strictly
 * necessary for the compiler, but provides an assurance that the signatures
 * of the functions in the dispatch table are correct.
 */
static OSSL_FUNC_mac_newctx_fn siphash_new;
static OSSL_FUNC_mac_dupctx_fn siphash_dup;
static OSSL_FUNC_mac_freectx_fn siphash_free;
static OSSL_FUNC_mac_gettable_ctx_params_fn siphash_gettable_ctx_params;
static OSSL_FUNC_mac_get_ctx_params_fn siphash_get_ctx_params;
static OSSL_FUNC_mac_settable_ctx_params_fn siphash_settable_ctx_params;
static OSSL_FUNC_mac_set_ctx_params_fn siphash_set_params;
static OSSL_FUNC_mac_init_fn siphash_init;
static OSSL_FUNC_mac_update_fn siphash_update;
static OSSL_FUNC_mac_final_fn siphash_final;

struct siphash_data_st {
    void *provctx;
    SIPHASH siphash; /* Siphash data */
    SIPHASH sipcopy; /* Siphash data copy for reinitialization */
    unsigned int crounds, drounds;
};

static unsigned int crounds(struct siphash_data_st *ctx)
{
    return ctx->crounds != 0 ? ctx->crounds : SIPHASH_C_ROUNDS;
}

static unsigned int drounds(struct siphash_data_st *ctx)
{
    return ctx->drounds != 0 ? ctx->drounds : SIPHASH_D_ROUNDS;
}

static void *siphash_new(void *provctx)
{
    struct siphash_data_st *ctx;

    if (!ossl_prov_is_running())
        return NULL;
    ctx = OPENSSL_zalloc(sizeof(*ctx));
    if (ctx != NULL)
        ctx->provctx = provctx;
    return ctx;
}

static void siphash_free(void *vmacctx)
{
    OPENSSL_free(vmacctx);
}

static void *siphash_dup(void *vsrc)
{
    struct siphash_data_st *ssrc = vsrc;
    struct siphash_data_st *sdst;

    if (!ossl_prov_is_running())
        return NULL;
    sdst = OPENSSL_malloc(sizeof(*sdst));
    if (sdst == NULL)
        return NULL;

    *sdst = *ssrc;
    return sdst;
}

static size_t siphash_size(void *vmacctx)
{
    struct siphash_data_st *ctx = vmacctx;

    return SipHash_hash_size(&ctx->siphash);
}

static int siphash_setkey(struct siphash_data_st *ctx,
    const unsigned char *key, size_t keylen)
{
    int ret;

    if (keylen != SIPHASH_KEY_SIZE)
        return 0;
    ret = SipHash_Init(&ctx->siphash, key, crounds(ctx), drounds(ctx));
    if (ret)
        ctx->sipcopy = ctx->siphash;
    return ret;
}

static int siphash_init(void *vmacctx, const unsigned char *key, size_t keylen,
    const OSSL_PARAM params[])
{
    struct siphash_data_st *ctx = vmacctx;

    if (!ossl_prov_is_running() || !siphash_set_params(ctx, params))
        return 0;
    /*
     * Without a key, there is not much to do here,
     * The actual initialization happens through controls.
     */
    if (key == NULL) {
        ctx->siphash = ctx->sipcopy;
        return 1;
    }
    return siphash_setkey(ctx, key, keylen);
}

static int siphash_update(void *vmacctx, const unsigned char *data,
    size_t datalen)
{
    struct siphash_data_st *ctx = vmacctx;

    if (datalen == 0)
        return 1;

    SipHash_Update(&ctx->siphash, data, datalen);
    return 1;
}

static int siphash_final(void *vmacctx, unsigned char *out, size_t *outl,
    size_t outsize)
{
    struct siphash_data_st *ctx = vmacctx;
    size_t hlen = siphash_size(ctx);

    if (!ossl_prov_is_running() || outsize < hlen)
        return 0;

    *outl = hlen;
    return SipHash_Final(&ctx->siphash, out, hlen);
}

/* clang-format off */
/* Machine generated by util/perl/OpenSSL/paramnames.pm */
#ifndef siphash_get_ctx_params_list
static const OSSL_PARAM siphash_get_ctx_params_list[] = {
    OSSL_PARAM_size_t(OSSL_MAC_PARAM_SIZE, NULL),
    OSSL_PARAM_uint(OSSL_MAC_PARAM_C_ROUNDS, NULL),
    OSSL_PARAM_uint(OSSL_MAC_PARAM_D_ROUNDS, NULL),
    OSSL_PARAM_END
};
#endif

#ifndef siphash_get_ctx_params_st
struct siphash_get_ctx_params_st {
    OSSL_PARAM *c;
    OSSL_PARAM *d;
    OSSL_PARAM *size;
};
#endif

#ifndef siphash_get_ctx_params_decoder
static int siphash_get_ctx_params_decoder
    (const OSSL_PARAM *p, struct siphash_get_ctx_params_st *r)
{
    const char *s;

    memset(r, 0, sizeof(*r));
    if (p != NULL)
        for (; (s = p->key) != NULL; p++)
            switch(s[0]) {
            default:
                break;
            case 'c':
                if (ossl_likely(strcmp("-rounds", s + 1) == 0)) {
                    /* OSSL_MAC_PARAM_C_ROUNDS */
                    if (ossl_unlikely(r->c != NULL)) {
                        ERR_raise_data(ERR_LIB_PROV, PROV_R_REPEATED_PARAMETER,
                                       "param %s is repeated", s);
                        return 0;
                    }
                    r->c = (OSSL_PARAM *)p;
                }
                break;
            case 'd':
                if (ossl_likely(strcmp("-rounds", s + 1) == 0)) {
                    /* OSSL_MAC_PARAM_D_ROUNDS */
                    if (ossl_unlikely(r->d != NULL)) {
                        ERR_raise_data(ERR_LIB_PROV, PROV_R_REPEATED_PARAMETER,
                                       "param %s is repeated", s);
                        return 0;
                    }
                    r->d = (OSSL_PARAM *)p;
                }
                break;
            case 's':
                if (ossl_likely(strcmp("ize", s + 1) == 0)) {
                    /* OSSL_MAC_PARAM_SIZE */
                    if (ossl_unlikely(r->size != NULL)) {
                        ERR_raise_data(ERR_LIB_PROV, PROV_R_REPEATED_PARAMETER,
                                       "param %s is repeated", s);
                        return 0;
                    }
                    r->size = (OSSL_PARAM *)p;
                }
            }
    return 1;
}
#endif
/* End of machine generated */
/* clang-format on */

static const OSSL_PARAM *siphash_gettable_ctx_params(ossl_unused void *ctx,
    ossl_unused void *provctx)
{
    return siphash_get_ctx_params_list;
}

static int siphash_get_ctx_params(void *vmacctx, OSSL_PARAM params[])
{
    struct siphash_data_st *ctx = vmacctx;
    struct siphash_get_ctx_params_st p;

    if (ctx == NULL || !siphash_get_ctx_params_decoder(params, &p))
        return 0;

    if (p.size != NULL && !OSSL_PARAM_set_size_t(p.size, siphash_size(vmacctx)))
        return 0;
    if (p.c != NULL && !OSSL_PARAM_set_uint(p.c, crounds(ctx)))
        return 0;
    if (p.d != NULL && !OSSL_PARAM_set_uint(p.d, drounds(ctx)))
        return 0;
    return 1;
}

/* clang-format off */
/* Machine generated by util/perl/OpenSSL/paramnames.pm */
#ifndef siphash_set_params_list
static const OSSL_PARAM siphash_set_params_list[] = {
    OSSL_PARAM_size_t(OSSL_MAC_PARAM_SIZE, NULL),
    OSSL_PARAM_octet_string(OSSL_MAC_PARAM_KEY, NULL, 0),
    OSSL_PARAM_uint(OSSL_MAC_PARAM_C_ROUNDS, NULL),
    OSSL_PARAM_uint(OSSL_MAC_PARAM_D_ROUNDS, NULL),
    OSSL_PARAM_END
};
#endif

#ifndef siphash_set_params_st
struct siphash_set_params_st {
    OSSL_PARAM *c;
    OSSL_PARAM *d;
    OSSL_PARAM *key;
    OSSL_PARAM *size;
};
#endif

#ifndef siphash_set_params_decoder
static int siphash_set_params_decoder
    (const OSSL_PARAM *p, struct siphash_set_params_st *r)
{
    const char *s;

    memset(r, 0, sizeof(*r));
    if (p != NULL)
        for (; (s = p->key) != NULL; p++)
            switch(s[0]) {
            default:
                break;
            case 'c':
                if (ossl_likely(strcmp("-rounds", s + 1) == 0)) {
                    /* OSSL_MAC_PARAM_C_ROUNDS */
                    if (ossl_unlikely(r->c != NULL)) {
                        ERR_raise_data(ERR_LIB_PROV, PROV_R_REPEATED_PARAMETER,
                                       "param %s is repeated", s);
                        return 0;
                    }
                    r->c = (OSSL_PARAM *)p;
                }
                break;
            case 'd':
                if (ossl_likely(strcmp("-rounds", s + 1) == 0)) {
                    /* OSSL_MAC_PARAM_D_ROUNDS */
                    if (ossl_unlikely(r->d != NULL)) {
                        ERR_raise_data(ERR_LIB_PROV, PROV_R_REPEATED_PARAMETER,
                                       "param %s is repeated", s);
                        return 0;
                    }
                    r->d = (OSSL_PARAM *)p;
                }
                break;
            case 'k':
                if (ossl_likely(strcmp("ey", s + 1) == 0)) {
                    /* OSSL_MAC_PARAM_KEY */
                    if (ossl_unlikely(r->key != NULL)) {
                        ERR_raise_data(ERR_LIB_PROV, PROV_R_REPEATED_PARAMETER,
                                       "param %s is repeated", s);
                        return 0;
                    }
                    r->key = (OSSL_PARAM *)p;
                }
                break;
            case 's':
                if (ossl_likely(strcmp("ize", s + 1) == 0)) {
                    /* OSSL_MAC_PARAM_SIZE */
                    if (ossl_unlikely(r->size != NULL)) {
                        ERR_raise_data(ERR_LIB_PROV, PROV_R_REPEATED_PARAMETER,
                                       "param %s is repeated", s);
                        return 0;
                    }
                    r->size = (OSSL_PARAM *)p;
                }
            }
    return 1;
}
#endif
/* End of machine generated */
/* clang-format on */

static const OSSL_PARAM *siphash_settable_ctx_params(ossl_unused void *ctx,
    void *provctx)
{
    return siphash_set_params_list;
}

static int siphash_set_params(void *vmacctx, const OSSL_PARAM *params)
{
    struct siphash_data_st *ctx = vmacctx;
    struct siphash_set_params_st p;
    size_t size;

    if (ctx == NULL || !siphash_set_params_decoder(params, &p))
        return 0;

    if (p.size != NULL) {
        if (!OSSL_PARAM_get_size_t(p.size, &size)
            || !SipHash_set_hash_size(&ctx->siphash, size)
            || !SipHash_set_hash_size(&ctx->sipcopy, size))
            return 0;
    }
    if (p.c != NULL && !OSSL_PARAM_get_uint(p.c, &ctx->crounds))
        return 0;
    if (p.d != NULL && !OSSL_PARAM_get_uint(p.d, &ctx->drounds))
        return 0;
    if (p.key != NULL)
        if (p.key->data_type != OSSL_PARAM_OCTET_STRING
            || !siphash_setkey(ctx, p.key->data, p.key->data_size))
            return 0;
    return 1;
}

const OSSL_DISPATCH ossl_siphash_functions[] = {
    { OSSL_FUNC_MAC_NEWCTX, (void (*)(void))siphash_new },
    { OSSL_FUNC_MAC_DUPCTX, (void (*)(void))siphash_dup },
    { OSSL_FUNC_MAC_FREECTX, (void (*)(void))siphash_free },
    { OSSL_FUNC_MAC_INIT, (void (*)(void))siphash_init },
    { OSSL_FUNC_MAC_UPDATE, (void (*)(void))siphash_update },
    { OSSL_FUNC_MAC_FINAL, (void (*)(void))siphash_final },
    { OSSL_FUNC_MAC_GETTABLE_CTX_PARAMS,
        (void (*)(void))siphash_gettable_ctx_params },
    { OSSL_FUNC_MAC_GET_CTX_PARAMS, (void (*)(void))siphash_get_ctx_params },
    { OSSL_FUNC_MAC_SETTABLE_CTX_PARAMS,
        (void (*)(void))siphash_settable_ctx_params },
    { OSSL_FUNC_MAC_SET_CTX_PARAMS, (void (*)(void))siphash_set_params },
    OSSL_DISPATCH_END
};
