crypto: add in secp256k1 support (#5500)

Secp256k1 was removed in the protobuf migration, this pr adds it back in order to provide this functionality for users (band)

Closes: #5495

types/params_test.go

@@ -13,7 +13,8 @@ import (
 )
 
 var (
-	valEd25519 = []string{ABCIPubKeyTypeEd25519}
+	valEd25519   = []string{ABCIPubKeyTypeEd25519}
+	valSecp256k1 = []string{ABCIPubKeyTypeSecp256k1}
 )
 
 func TestConsensusParamsValidation(t *testing.T) {
@@ -127,10 +128,10 @@ func TestConsensusParamsUpdate(t *testing.T) {
 					MaxBytes:        50,
 				},
 				Validator: &tmproto.ValidatorParams{
-					PubKeyTypes: valEd25519,
+					PubKeyTypes: valSecp256k1,
 				},
 			},
-			makeParams(100, 200, 10, 300, 50, valEd25519),
+			makeParams(100, 200, 10, 300, 50, valSecp256k1),
 		},
 	}
 	for _, tc := range testCases {

types/protobuf.go

@@ -8,6 +8,7 @@ import (
 	"github.com/tendermint/tendermint/crypto"
 	"github.com/tendermint/tendermint/crypto/ed25519"
 	cryptoenc "github.com/tendermint/tendermint/crypto/encoding"
+	"github.com/tendermint/tendermint/crypto/secp256k1"
 	tmproto "github.com/tendermint/tendermint/proto/tendermint/types"
 )
 
@@ -15,13 +16,15 @@ import (
 // Use strings to distinguish types in ABCI messages
 
 const (
-	ABCIPubKeyTypeEd25519 = "ed25519"
+	ABCIPubKeyTypeEd25519   = ed25519.KeyType
+	ABCIPubKeyTypeSecp256k1 = secp256k1.KeyType
 )
 
 // TODO: Make non-global by allowing for registration of more pubkey types
 
 var ABCIPubKeyTypesToNames = map[string]string{
-	ABCIPubKeyTypeEd25519: ed25519.PubKeyName,
+	ABCIPubKeyTypeEd25519:   ed25519.PubKeyName,
+	ABCIPubKeyTypeSecp256k1: secp256k1.PubKeyName,
 }
 
 //-------------------------------------------------------