Files
rippled/src/libxrpl/protocol/Sign.cpp
2026-02-19 23:30:00 +00:00

89 lines
2.8 KiB
C++

#include <xrpl/protocol/AccountID.h>
#include <xrpl/protocol/HashPrefix.h>
#include <xrpl/protocol/KeyType.h>
#include <xrpl/protocol/PublicKey.h>
#include <xrpl/protocol/SField.h>
#include <xrpl/protocol/STExchange.h>
#include <xrpl/protocol/STObject.h>
#include <xrpl/protocol/SecretKey.h>
#include <xrpl/protocol/Serializer.h>
#include <xrpl/protocol/Sign.h>
namespace xrpl {
void
sign(
STObject& st,
HashPrefix const& prefix,
KeyType type,
SecretKey const& sk,
SF_VL const& sigField)
{
Serializer ss;
ss.add32(prefix);
st.addWithoutSigningFields(ss);
set(st, sigField, sign(type, sk, ss.slice()));
}
bool
verify(STObject const& st, HashPrefix const& prefix, PublicKey const& pk, SF_VL const& sigField)
{
auto const sig = get(st, sigField);
if (!sig)
return false;
Serializer ss;
ss.add32(prefix);
st.addWithoutSigningFields(ss);
return verify(pk, Slice(ss.data(), ss.size()), Slice(sig->data(), sig->size()));
}
// Questions regarding buildMultiSigningData:
//
// Why do we include the Signer.Account in the blob to be signed?
//
// Unless you include the Account which is signing in the signing blob,
// you could swap out any Signer.Account for any other, which may also
// be on the SignerList and have a RegularKey matching the
// Signer.SigningPubKey.
//
// That RegularKey may be set to allow some 3rd party to sign transactions
// on the account's behalf, and that RegularKey could be common amongst all
// users of the 3rd party. That's just one example of sharing the same
// RegularKey amongst various accounts and just one vulnerability.
//
// "When you have something that's easy to do that makes entire classes of
// attacks clearly and obviously impossible, you need a damn good reason
// not to do it." -- David Schwartz
//
// Why would we include the signingFor account in the blob to be signed?
//
// In the current signing scheme, the account that a signer is `signing
// for/on behalf of` is the tx_json.Account.
//
// Later we might support more levels of signing. Suppose Bob is a signer
// for Alice, and Carol is a signer for Bob, so Carol can sign for Bob who
// signs for Alice. But suppose Alice has two signers: Bob and Dave. If
// Carol is a signer for both Bob and Dave, then the signature needs to
// distinguish between Carol signing for Bob and Carol signing for Dave.
//
// So, if we support multiple levels of signing, then we'll need to
// incorporate the "signing for" accounts into the signing data as well.
Serializer
buildMultiSigningData(STObject const& obj, AccountID const& signingID)
{
Serializer s{startMultiSigningData(obj)};
finishMultiSigningData(signingID, s);
return s;
}
Serializer
startMultiSigningData(STObject const& obj)
{
Serializer s;
s.add32(HashPrefix::txMultiSign);
obj.addWithoutSigningFields(s);
return s;
}
} // namespace xrpl