/*
 * Copyright 2000-2019 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
 */

/* EVP_MD_CTX related stuff */

struct evp_md_ctx_st {
    const EVP_MD *reqdigest;    /* The original requested digest */
    const EVP_MD *digest;
    ENGINE *engine;             /* functional reference if 'digest' is
                                 * ENGINE-provided */
    unsigned long flags;
    void *md_data;
    /* Public key context for sign/verify */
    EVP_PKEY_CTX *pctx;
    /* Update function: usually copied from EVP_MD */
    int (*update) (EVP_MD_CTX *ctx, const void *data, size_t count);

    /* Provider ctx */
    void *provctx;
    EVP_MD *fetched_digest;
} /* EVP_MD_CTX */ ;

struct evp_cipher_ctx_st {
    const EVP_CIPHER *cipher;
    ENGINE *engine;             /* functional reference if 'cipher' is
                                 * ENGINE-provided */
    int encrypt;                /* encrypt or decrypt */
    int buf_len;                /* number we have left */
    unsigned char oiv[EVP_MAX_IV_LENGTH]; /* original iv */
    unsigned char iv[EVP_MAX_IV_LENGTH]; /* working iv */
    unsigned char buf[EVP_MAX_BLOCK_LENGTH]; /* saved partial block */
    int num;                    /* used by cfb/ofb/ctr mode */
    /* FIXME: Should this even exist? It appears unused */
    void *app_data;             /* application stuff */
    int key_len;                /* May change for variable length cipher */
    unsigned long flags;        /* Various flags */
    void *cipher_data;          /* per EVP data */
    int final_used;
    int block_mask;
    unsigned char final[EVP_MAX_BLOCK_LENGTH]; /* possible final block */

    /* Provider ctx */
    void *provctx;
    EVP_CIPHER *fetched_cipher;
} /* EVP_CIPHER_CTX */ ;

struct evp_mac_ctx_st {
    const EVP_MAC *meth;         /* Method structure */
    void *data;                  /* Individual method data */
} /* EVP_MAC_CTX */;

struct evp_kdf_ctx_st {
    const EVP_KDF *meth;         /* Method structure */
    EVP_KDF_IMPL *impl;          /* Algorithm-specific data */
} /* EVP_KDF_CTX */ ;

int PKCS5_v2_PBKDF2_keyivgen(EVP_CIPHER_CTX *ctx, const char *pass,
                             int passlen, ASN1_TYPE *param,
                             const EVP_CIPHER *c, const EVP_MD *md,
                             int en_de);

struct evp_Encode_Ctx_st {
    /* number saved in a partial encode/decode */
    int num;
    /*
     * The length is either the output line length (in input bytes) or the
     * shortest input line length that is ok.  Once decoding begins, the
     * length is adjusted up each time a longer line is decoded
     */
    int length;
    /* data to encode */
    unsigned char enc_data[80];
    /* number read on current line */
    int line_num;
    unsigned int flags;
};

typedef struct evp_pbe_st EVP_PBE_CTL;
DEFINE_STACK_OF(EVP_PBE_CTL)

int is_partially_overlapping(const void *ptr1, const void *ptr2, int len);

#include <openssl/ossl_typ.h>
#include <openssl/core.h>

void *evp_generic_fetch(OPENSSL_CTX *ctx, int operation_id,
                        const char *algorithm, const char *properties,
                        void *(*new_method)(const OSSL_DISPATCH *fns,
                                            OSSL_PROVIDER *prov),
                        int (*up_ref_method)(void *),
                        void (*free_method)(void *));

/* Helper functions to avoid duplicating code */

/*
 * The callbacks implement different ways to pass a params array to the
 * provider.  They will return one of these values:
 *
 * -2 if the method doesn't come from a provider
 *    (evp_do_param will return this to the called)
 * -1 if the provider doesn't offer the desired function
 *    (evp_do_param will raise an error and return 0)
 * or the return value from the desired function
 *    (evp_do_param will return it to the caller)
 */
int evp_do_ciph_getparams(const void *vciph, void *ignored,
                          OSSL_PARAM params[]);
int evp_do_ciph_ctx_getparams(const void *vciph, void *provctx,
                              OSSL_PARAM params[]);
int evp_do_ciph_ctx_setparams(const void *vciph, void *provctx,
                              OSSL_PARAM params[]);

/*-
 * prepares a singular parameter, then calls the callback to execute.
 *
 * |method|   points to the method used by the callback.
 *            EVP_CIPHER, EVP_MD, ...
 * |ptr|      points at the data to transfer.
 * |sz|       is the size of the data to transfer.
 * |key|      is the name of the parameter to pass.
 * |datatype| is the data type of the parameter to pass.
 * |cb|       is the callback that actually performs the parameter passing
 * |cb_ctx|   is the cipher context
 */
int evp_do_param(const void *method, void *ptr, size_t sz, const char *key,
                 int datatype,
                 int (*cb)(const void *method, void *ctx, OSSL_PARAM params[]),
                 void *cb_ctx);