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#ifndef LIGHTNING_COMMON_DERIVE_BASEPOINTS_H
#define LIGHTNING_COMMON_DERIVE_BASEPOINTS_H
#include "config.h"
#include <assert.h>
#include <bitcoin/privkey.h>
#include <bitcoin/pubkey.h>
#include <ccan/build_assert/build_assert.h>
#include <ccan/crypto/shachain/shachain.h>
struct sha256;
struct basepoints {
struct pubkey revocation;
struct pubkey payment;
struct pubkey htlc;
struct pubkey delayed_payment;
};
struct secrets {
struct privkey funding_privkey;
struct secret revocation_basepoint_secret;
struct secret payment_basepoint_secret;
struct secret htlc_basepoint_secret;
struct secret delayed_payment_basepoint_secret;
};
/**
* derive_basepoints - given a (per-peer) seed, get the basepoints
* @seed: (in) seed (derived by master daemon from counter and main seed)
* @funding_pubkey: (out) pubkey for funding tx output (if non-NULL)
* @basepoints: (out) basepoints for channel (if non-NULL)
* @secrets: (out) basepoints for channel (if non-NULL)
* @shaseed: (out) seed for shachain (if non-NULL)
*/
bool derive_basepoints(const struct secret *seed,
struct pubkey *funding_pubkey,
struct basepoints *basepoints,
struct secrets *secrets,
struct sha256 *shaseed);
/**
* derive_funding_key - given a (per-peer) seed, get just funding key
* @seed: (in) seed (derived by master daemon from counter and main seed)
* @funding_pubkey: (out) pubkey for funding tx output (if non-NULL)
* @funding_privkey: (out) privkey for funding tx output (if non-NULL)
*
* This is a cut-down version of derive_basepoints.
*/
bool derive_funding_key(const struct secret *seed,
struct pubkey *funding_pubkey,
struct privkey *funding_privkey);
/**
* derive_payment_basepoint - given a (per-channel) seed, get just payment basepoint
* @seed: (in) seed (derived by master daemon from counter and main seed)
* @payment_basepoint: (out) basepoint for payment output (if non-NULL)
* @payment_secret: (out) secret for payment basepoint (if non-NULL)
*
* This is a cut-down version of derive_basepoints.
*/
bool derive_payment_basepoint(const struct secret *seed,
struct pubkey *payment_basepoint,
struct secret *payment_secret);
/**
* derive_shaseed - given a (per-peer) seed, get just the shaseed
* @seed: (in) seed (derived by master daemon from counter and main seed)
* @shaseed: (out) seed for shachain
*
* This is a cut-down version of derive_basepoints.
*/
bool derive_shaseed(const struct secret *seed, struct sha256 *shaseed);
/**
* derive_delayed_payment_basepoint - give a (per-channel) seed, get just delayed payment basepoint
* @seed: (in) seed (derived by master daemon from counter and main seed)
* @delayed_payment_basepoint: (out) basepoint for payment output (if non-NULL)
* @delayed_payment_secret: (out) secret for payment basepoint (if non-NULL)
*
* This is a cut-down version of derive_basepoints.
*/
bool derive_delayed_payment_basepoint(const struct secret *seed,
struct pubkey *delayed_payment_basepoint,
struct secret *delayed_payment_secret);
/**
* derive_revocation_basepoint - given a (per-channel) seed, get just revocation basepoint
* @seed: (in) seed (derived by master daemon from counter and main seed)
* @payment_basepoint: (out) basepoint for revocation keys (if non-NULL)
* @payment_secret: (out) secret for revocation keys (if non-NULL)
*
* This is a cut-down version of derive_basepoints.
*/
bool derive_revocation_basepoint(const struct secret *seed,
struct pubkey *revocation_basepoint,
struct secret *revocation_secret);
/**
* derive_htlc_basepoint - give a (per-channel) seed, get just htlc basepoint
* @seed: (in) seed (derived by master daemon from counter and main seed)
* @htlc_basepoint: (out) basepoint for htlc output (if non-NULL)
* @htlc_secret: (out) secret for htlc basepoint (if non-NULL)
*
* This is a cut-down version of derive_basepoints.
*/
bool derive_htlc_basepoint(const struct secret *seed,
struct pubkey *htlc_basepoint,
struct secret *htlc_secret);
/**
* per_commit_secret - get a secret for this index.
* @shaseed: the sha256 seed
* @commit_secret: the returned per-commit secret.
* @per_commit_index: (in) which @commit_secret to return.
*
* Returns false if per_commit_index is invalid, or can't derive.
*/
bool per_commit_secret(const struct sha256 *shaseed,
struct secret *commit_secret,
u64 per_commit_index);
/**
* per_commit_point - get the per-commit-point for this index.
* @shaseed: the sha256 seed
* @commit_point: the returned per-commit point.
* @per_commit_index: (in) which @commit_point to return.
*/
bool per_commit_point(const struct sha256 *shaseed,
struct pubkey *commit_point,
u64 per_commit_index);
/* BOLT #3:
*
* The first secret used:
* - MUST be index 281474976710655,
* - and from there, the index is decremented.
*/
static inline u64 shachain_index(u64 per_commit_index)
{
BUILD_ASSERT((1ULL << SHACHAIN_BITS)-1 == 281474976710655);
assert(per_commit_index < (1ULL << SHACHAIN_BITS));
return (1ULL << SHACHAIN_BITS)-1 - per_commit_index;
}
static inline u64 revocations_received(const struct shachain *shachain)
{
return (1ULL << SHACHAIN_BITS) - (shachain_next_index(shachain) + 1);
}
bool shachain_get_secret(const struct shachain *shachain,
u64 commit_num,
struct secret *preimage);
void towire_basepoints(u8 **pptr, const struct basepoints *b);
void fromwire_basepoints(const u8 **ptr, size_t *max,
struct basepoints *b);
/* For --dev-force-channel-secrets. */
#if DEVELOPER
extern struct secrets *dev_force_channel_secrets;
extern struct sha256 *dev_force_channel_secrets_shaseed;
#endif
/* Note: these abort if !DEVELOPER */
void towire_secrets(u8 **pptr, const struct secrets *s);
void fromwire_secrets(const u8 **ptr, size_t *max, struct secrets *s);
#endif /* LIGHTNING_COMMON_DERIVE_BASEPOINTS_H */