base/xdr/Stellar-SCP.x
// Copyright 2015 Stellar Development Foundation and contributors. Licensed
// under the Apache License, Version 2.0. See the COPYING file at the root
// of this distribution or at http://www.apache.org/licenses/LICENSE-2.0
%#include "xdr/Stellar-types.h"
namespace stellar
{
typedef opaque Value<>;
struct SCPBallot
{
uint32 counter; // n
Value value; // x
};
enum SCPStatementType
{
SCP_ST_PREPARE = 0,
SCP_ST_CONFIRM = 1,
SCP_ST_EXTERNALIZE = 2,
SCP_ST_NOMINATE = 3
};
struct SCPNomination
{
Hash quorumSetHash; // D
Value votes<>; // X
Value accepted<>; // Y
};
struct SCPStatement
{
NodeID nodeID; // v
uint64 slotIndex; // i
union switch (SCPStatementType type)
{
case SCP_ST_PREPARE:
struct
{
Hash quorumSetHash; // D
SCPBallot ballot; // b
SCPBallot* prepared; // p
SCPBallot* preparedPrime; // p'
uint32 nC; // c.n
uint32 nH; // h.n
} prepare;
case SCP_ST_CONFIRM:
struct
{
SCPBallot ballot; // b
uint32 nPrepared; // p.n
uint32 nCommit; // c.n
uint32 nH; // h.n
Hash quorumSetHash; // D
} confirm;
case SCP_ST_EXTERNALIZE:
struct
{
SCPBallot commit; // c
uint32 nH; // h.n
Hash commitQuorumSetHash; // D used before EXTERNALIZE
} externalize;
case SCP_ST_NOMINATE:
SCPNomination nominate;
}
pledges;
};
struct SCPEnvelope
{
SCPStatement statement;
Signature signature;
};
// supports things like: A,B,C,(D,E,F),(G,H,(I,J,K,L))
// only allows 2 levels of nesting
struct SCPQuorumSet
{
uint32 threshold;
NodeID validators<>;
SCPQuorumSet innerSets<>;
};
}