P2SH address to use 126 as scriptId

interpreter/shared/src/main/scala/org/ergoplatform/ErgoAddress.scala

@@ -2,11 +2,11 @@ package org.ergoplatform
 
 import scorex.utils.Ints
 import org.ergoplatform.ErgoAddressEncoder.NetworkPrefix
-import scorex.crypto.hash.{Digest32, Blake2b256}
+import scorex.crypto.hash.{Blake2b256, Digest32}
 import scorex.util.encode.Base58
 import sigmastate.Values._
 import sigmastate._
-import sigmastate.crypto.DLogProtocol.{ProveDlogProp, ProveDlog}
+import sigmastate.crypto.DLogProtocol.{ProveDlog, ProveDlogProp}
 import sigmastate.exceptions.SigmaException
 import sigmastate.serialization._
 import sigmastate.utxo.{DeserializeContext, Slice}
@@ -128,7 +128,9 @@ object P2PKAddress {
   }
 }
 
-/** Implementation of pay-to-script-hash [[ErgoAddress]]. */
+/** Implementation of pay-to-script-hash [[ErgoAddress]].
+  * @param scriptHash first 192 bits of the Blake2b256 hash of serialized script bytes
+  */
 class Pay2SHAddress(val scriptHash: Array[Byte])(implicit val encoder: ErgoAddressEncoder) extends ErgoAddress {
   override val addressTypePrefix: Byte = Pay2SHAddress.addressTypePrefix
 
@@ -141,12 +143,12 @@ class Pay2SHAddress(val scriptHash: Array[Byte])(implicit val encoder: ErgoAddre
   /** The proposition which checks that `contextVar(scriptId)` has original script
     * (whose hash equals to this [[scriptHash]]) which evaluates to true.
     *
-    * Assumes the context variable is accessed as `getVar[Coll[Byte]](1).get`
+    * Assumes the context variable is accessed as `getVar[Coll[Byte]](126).get`
     * and contains serialized original script bytes.
     *
-    * NOTE: This script is not stored in [[contentBytes]] of the address.
+    * NOTE: This `script` field is not stored in [[contentBytes]] of the address.
     * So the address doesn't depend on this script which means this specific script can be
-    * changed without breaking the addresses.
+    * changed without breaking the existing p2sh addresses.
     *
     * NOTE: The ErgoTree is created without segregation of the constants.
     *
@@ -158,7 +160,7 @@ class Pay2SHAddress(val scriptHash: Array[Byte])(implicit val encoder: ErgoAddre
   override val script = {
     val hashEquals = EQ(
       Slice(CalcBlake2b256(GetVarByteArray(scriptId).get), IntConstant(0), IntConstant(24)),
-      scriptHash
+      ByteArrayConstant(scriptHash)
     )
     val scriptIsCorrect = DeserializeContext(scriptId, SSigmaProp)
     ErgoTree.withoutSegregation(SigmaAnd(hashEquals.toSigmaProp, scriptIsCorrect))
@@ -176,9 +178,10 @@ class Pay2SHAddress(val scriptHash: Array[Byte])(implicit val encoder: ErgoAddre
 
 object Pay2SHAddress {
   /** An id of the context variable used in pay-to-script-hash address script.
+    * Note, value 127 is used for strage rent in Ergo node, see org.ergoplatform.wallet.interpreter.ErgoInterpreter
     * @see [[Pay2SHAddress.script]]
     */
-  val scriptId = 1: Byte
+  val scriptId = 126: Byte
 
   /** Value added to the prefix byte in the serialized bytes of an encoded P2SH address.
     * @see [[ErgoAddressEncoder.toString]]
@@ -300,7 +303,7 @@ case class ErgoAddressEncoder(networkPrefix: NetworkPrefix) {
           new P2PKAddress(ProveDlog(p), contentBytes)
         case Pay2SHAddress.addressTypePrefix =>
           if (contentBytes.length != 24) { //192-bits hash used
-            throw new Exception(s"Improper content in P2SH script: $addrBase58Str")
+            throw new Exception(s"Invalid length of the hash bytes in P2SH address: $addrBase58Str")
           }
           new Pay2SHAddress(contentBytes)
         case Pay2SAddress.addressTypePrefix =>
@@ -328,7 +331,8 @@ case class ErgoAddressEncoder(networkPrefix: NetworkPrefix) {
   }
 
   /** Converts the given [[ErgoTree]] to the corresponding [[ErgoAddress]].
-    * It is inverse of [[ErgoAddress.script]] such that `fromProposition(addr.script) == addr`
+    * It is inverse of [[ErgoAddress.script]] such that
+    * `ErgoAddressEncoder.fromProposition(addr.script) == addr`
     *
     * @return Failure(ex) if the `proposition` cannot be converted to any type of address.
     */

sc/shared/src/test/scala/org/ergoplatform/ErgoAddressSpecification.scala

@@ -170,7 +170,7 @@ class ErgoAddressSpecification extends SigmaDslTesting
 
       assertExceptionThrown(
         ergoAddressEncoder.fromString(addrStr).getOrThrow,
-        t => t.getMessage.contains("Improper content in P2SH script: 41fKjb7zWNw")
+        t => t.getMessage.contains("Invalid length of the hash bytes in P2SH address: 41fKjb7zWNw")
       )
     }
 
@@ -228,7 +228,7 @@ class ErgoAddressSpecification extends SigmaDslTesting
   }
 
   def testPay2SHAddress(address: Pay2SHAddress, scriptBytes: Array[Byte]) = {
-    val scriptId = 1.toByte
+    val scriptId = Pay2SHAddress.scriptId
     val boxToSpend = testBox(10, address.script, creationHeight = 5)
     val ctx = ErgoLikeContextTesting.dummy(boxToSpend, activatedVersionInTests)
         .withExtension(ContextExtension(Seq(
@@ -271,7 +271,7 @@ class ErgoAddressSpecification extends SigmaDslTesting
       res
     }
 
-    val scriptVarId = 1.toByte
+    val scriptVarId = Pay2SHAddress.scriptId
     val script = "{ 1 < 2 }"
     val prop = compile(Map.empty, script).asBoolValue.toSigmaProp
     val scriptBytes = ValueSerializer.serialize(prop)