view ecc.h @ 1715:3974f087d9c0

Disallow leading lines before the ident for server (#102) Per RFC4253 4.2 clients must be able to process other lines of data before the version string, server behavior is not defined neither with MUST/SHOULD nor with MAY. If server process up to 50 lines too - it may cause too long hanging session with invalid/evil client that consume host resources and potentially may lead to DDoS on poor embedded boxes. Let's require first line from client to be version string and fail early if it's not - matches both RFC and real OpenSSH behavior.
author Vladislav Grishenko <themiron@users.noreply.github.com>
date Mon, 15 Jun 2020 18:22:18 +0500
parents d68d61e7056a
children
line wrap: on
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#ifndef DROPBEAR_DROPBEAR_ECC_H
#define DROPBEAR_DROPBEAR_ECC_H

#include "includes.h"

#include "buffer.h"

#if DROPBEAR_ECC

struct dropbear_ecc_curve {
	int ltc_size; /* to match the byte sizes in ltc_ecc_sets[] */
	const ltc_ecc_set_type *dp; /* curve domain parameters */
	const struct ltc_hash_descriptor *hash_desc;
	const char *name;
};

extern struct dropbear_ecc_curve ecc_curve_nistp256;
extern struct dropbear_ecc_curve ecc_curve_nistp384;
extern struct dropbear_ecc_curve ecc_curve_nistp521;
extern struct dropbear_ecc_curve *dropbear_ecc_curves[];

void dropbear_ecc_fill_dp(void);
struct dropbear_ecc_curve* curve_for_dp(const ltc_ecc_set_type *dp);

/* "pubkey" refers to a point, but LTC uses ecc_key structure for both public
   and private keys */
void buf_put_ecc_raw_pubkey_string(buffer *buf, ecc_key *key);
ecc_key * buf_get_ecc_raw_pubkey(buffer *buf, const struct dropbear_ecc_curve *curve);
int buf_get_ecc_privkey_string(buffer *buf, ecc_key *key);

mp_int * dropbear_ecc_shared_secret(ecc_key *pub_key, const ecc_key *priv_key);

#endif

#endif /* DROPBEAR_DROPBEAR_ECC_H */