|
package proxy
|
|
|
|
import (
|
|
"fmt"
|
|
|
|
"github.com/pkg/errors"
|
|
|
|
cmn "github.com/tendermint/tendermint/libs/common"
|
|
|
|
"github.com/tendermint/tendermint/lite"
|
|
rpcclient "github.com/tendermint/tendermint/rpc/client"
|
|
ctypes "github.com/tendermint/tendermint/rpc/core/types"
|
|
"github.com/tendermint/tendermint/types"
|
|
)
|
|
|
|
// KeyProof represents a proof of existence or absence of a single key.
|
|
// Copied from iavl repo. TODO
|
|
type KeyProof interface {
|
|
// Verify verfies the proof is valid. To verify absence,
|
|
// the value should be nil.
|
|
Verify(key, value, root []byte) error
|
|
|
|
// Root returns the root hash of the proof.
|
|
Root() []byte
|
|
|
|
// Serialize itself
|
|
Bytes() []byte
|
|
}
|
|
|
|
// GetWithProof will query the key on the given node, and verify it has
|
|
// a valid proof, as defined by the Verifier.
|
|
//
|
|
// If there is any error in checking, returns an error.
|
|
// If val is non-empty, proof should be KeyExistsProof
|
|
// If val is empty, proof should be KeyMissingProof
|
|
func GetWithProof(key []byte, reqHeight int64, node rpcclient.Client,
|
|
cert lite.Verifier) (
|
|
val cmn.HexBytes, height int64, proof KeyProof, err error) {
|
|
|
|
if reqHeight < 0 {
|
|
err = errors.Errorf("Height cannot be negative")
|
|
return
|
|
}
|
|
|
|
_resp, proof, err := GetWithProofOptions("/key", key,
|
|
rpcclient.ABCIQueryOptions{Height: int64(reqHeight)},
|
|
node, cert)
|
|
if _resp != nil {
|
|
resp := _resp.Response
|
|
val, height = resp.Value, resp.Height
|
|
}
|
|
return val, height, proof, err
|
|
}
|
|
|
|
// GetWithProofOptions is useful if you want full access to the ABCIQueryOptions
|
|
func GetWithProofOptions(path string, key []byte, opts rpcclient.ABCIQueryOptions,
|
|
node rpcclient.Client, cert lite.Verifier) (
|
|
*ctypes.ResultABCIQuery, KeyProof, error) {
|
|
|
|
_resp, err := node.ABCIQueryWithOptions(path, key, opts)
|
|
if err != nil {
|
|
return nil, nil, err
|
|
}
|
|
resp := _resp.Response
|
|
|
|
// make sure the proof is the proper height
|
|
if resp.IsErr() {
|
|
err = errors.Errorf("Query error for key %d: %d", key, resp.Code)
|
|
return nil, nil, err
|
|
}
|
|
if len(resp.Key) == 0 || len(resp.Proof) == 0 {
|
|
return nil, nil, ErrNoData()
|
|
}
|
|
if resp.Height == 0 {
|
|
return nil, nil, errors.New("Height returned is zero")
|
|
}
|
|
|
|
// AppHash for height H is in header H+1
|
|
signedHeader, err := GetCertifiedCommit(resp.Height+1, node, cert)
|
|
if err != nil {
|
|
return nil, nil, err
|
|
}
|
|
|
|
_ = signedHeader
|
|
return &ctypes.ResultABCIQuery{Response: resp}, nil, nil
|
|
|
|
/* // TODO refactor so iavl stuff is not in tendermint core
|
|
// https://github.com/tendermint/tendermint/issues/1183
|
|
if len(resp.Value) > 0 {
|
|
// The key was found, construct a proof of existence.
|
|
proof, err := iavl.ReadKeyProof(resp.Proof)
|
|
if err != nil {
|
|
return nil, nil, errors.Wrap(err, "Error reading proof")
|
|
}
|
|
|
|
eproof, ok := proof.(*iavl.KeyExistsProof)
|
|
if !ok {
|
|
return nil, nil, errors.New("Expected KeyExistsProof for non-empty value")
|
|
}
|
|
|
|
// Validate the proof against the certified header to ensure data integrity.
|
|
err = eproof.Verify(resp.Key, resp.Value, signedHeader.AppHash)
|
|
if err != nil {
|
|
return nil, nil, errors.Wrap(err, "Couldn't verify proof")
|
|
}
|
|
return &ctypes.ResultABCIQuery{Response: resp}, eproof, nil
|
|
}
|
|
|
|
// The key wasn't found, construct a proof of non-existence.
|
|
proof, err := iavl.ReadKeyProof(resp.Proof)
|
|
if err != nil {
|
|
return nil, nil, errors.Wrap(err, "Error reading proof")
|
|
}
|
|
|
|
aproof, ok := proof.(*iavl.KeyAbsentProof)
|
|
if !ok {
|
|
return nil, nil, errors.New("Expected KeyAbsentProof for empty Value")
|
|
}
|
|
|
|
// Validate the proof against the certified header to ensure data integrity.
|
|
err = aproof.Verify(resp.Key, nil, signedHeader.AppHash)
|
|
if err != nil {
|
|
return nil, nil, errors.Wrap(err, "Couldn't verify proof")
|
|
}
|
|
return &ctypes.ResultABCIQuery{Response: resp}, aproof, ErrNoData()
|
|
*/
|
|
}
|
|
|
|
// GetCertifiedCommit gets the signed header for a given height and certifies
|
|
// it. Returns error if unable to get a proven header.
|
|
func GetCertifiedCommit(h int64, client rpcclient.Client, cert lite.Verifier) (types.SignedHeader, error) {
|
|
|
|
// FIXME: cannot use cert.GetByHeight for now, as it also requires
|
|
// Validators and will fail on querying tendermint for non-current height.
|
|
// When this is supported, we should use it instead...
|
|
rpcclient.WaitForHeight(client, h, nil)
|
|
cresp, err := client.Commit(&h)
|
|
if err != nil {
|
|
return types.SignedHeader{}, err
|
|
}
|
|
|
|
// Validate downloaded checkpoint with our request and trust store.
|
|
sh := cresp.SignedHeader
|
|
if sh.Height != h {
|
|
return types.SignedHeader{}, fmt.Errorf("height mismatch: want %v got %v",
|
|
h, sh.Height)
|
|
}
|
|
|
|
if err = cert.Certify(sh); err != nil {
|
|
return types.SignedHeader{}, err
|
|
}
|
|
|
|
return sh, nil
|
|
}
|