/* $OpenBSD: rsa_locl.h,v 1.13 2022/07/04 12:23:30 tb Exp $ */

__BEGIN_HIDDEN_DECLS

#define RSA_MIN_MODULUS_BITS    512

/* Macros to test if a pkey or ctx is for a PSS key */
#define pkey_is_pss(pkey) (pkey->ameth->pkey_id == EVP_PKEY_RSA_PSS)
#define pkey_ctx_is_pss(ctx) (ctx->pmeth->pkey_id == EVP_PKEY_RSA_PSS)

struct rsa_meth_st {
        char *name;
        int (*rsa_pub_enc)(int flen, const unsigned char *from,
            unsigned char *to, RSA *rsa, int padding);
        int (*rsa_pub_dec)(int flen, const unsigned char *from,
            unsigned char *to, RSA *rsa, int padding);
        int (*rsa_priv_enc)(int flen, const unsigned char *from,
            unsigned char *to, RSA *rsa, int padding);
        int (*rsa_priv_dec)(int flen, const unsigned char *from,
            unsigned char *to, RSA *rsa, int padding);
        int (*rsa_mod_exp)(BIGNUM *r0, const BIGNUM *I, RSA *rsa,
            BN_CTX *ctx); /* Can be null */
        int (*bn_mod_exp)(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
            const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *m_ctx); /* Can be null */
        int (*init)(RSA *rsa);          /* called at new */
        int (*finish)(RSA *rsa);        /* called at free */
        int flags;                      /* RSA_METHOD_FLAG_* things */
        char *app_data;                 /* may be needed! */
/* New sign and verify functions: some libraries don't allow arbitrary data
 * to be signed/verified: this allows them to be used. Note: for this to work
 * the RSA_public_decrypt() and RSA_private_encrypt() should *NOT* be used
 * RSA_sign(), RSA_verify() should be used instead. Note: for backwards
 * compatibility this functionality is only enabled if the RSA_FLAG_SIGN_VER
 * option is set in 'flags'.
 */
        int (*rsa_sign)(int type, const unsigned char *m, unsigned int m_length,
            unsigned char *sigret, unsigned int *siglen, const RSA *rsa);
        int (*rsa_verify)(int dtype, const unsigned char *m,
            unsigned int m_length, const unsigned char *sigbuf,
            unsigned int siglen, const RSA *rsa);
/* If this callback is NULL, the builtin software RSA key-gen will be used. This
 * is for behavioural compatibility whilst the code gets rewired, but one day
 * it would be nice to assume there are no such things as "builtin software"
 * implementations. */
        int (*rsa_keygen)(RSA *rsa, int bits, BIGNUM *e, BN_GENCB *cb);
};

struct rsa_st {
        /* The first parameter is used to pickup errors where
         * this is passed instead of aEVP_PKEY, it is set to 0 */
        int pad;
        long version;
        const RSA_METHOD *meth;

        /* functional reference if 'meth' is ENGINE-provided */
        ENGINE *engine;
        BIGNUM *n;
        BIGNUM *e;
        BIGNUM *d;
        BIGNUM *p;
        BIGNUM *q;
        BIGNUM *dmp1;
        BIGNUM *dmq1;
        BIGNUM *iqmp;

        /* Parameter restrictions for PSS only keys. */
        RSA_PSS_PARAMS *pss;

        /* be careful using this if the RSA structure is shared */
        CRYPTO_EX_DATA ex_data;
        int references;
        int flags;

        /* Used to cache montgomery values */
        BN_MONT_CTX *_method_mod_n;
        BN_MONT_CTX *_method_mod_p;
        BN_MONT_CTX *_method_mod_q;

        /* all BIGNUM values are actually in the following data, if it is not
         * NULL */
        BN_BLINDING *blinding;
        BN_BLINDING *mt_blinding;
};

RSA_PSS_PARAMS *rsa_pss_params_create(const EVP_MD *sigmd, const EVP_MD *mgf1md,
    int saltlen);
int rsa_pss_get_param(const RSA_PSS_PARAMS *pss, const EVP_MD **pmd,
    const EVP_MD **pmgf1md, int *psaltlen);

extern int int_rsa_verify(int dtype, const unsigned char *m,
    unsigned int m_len, unsigned char *rm, size_t *prm_len,
    const unsigned char *sigbuf, size_t siglen, RSA *rsa);

__END_HIDDEN_DECLS