Merge bitcoin#12460: Assert CPubKey::ValidLength to the pubkey's header-relevant size

f8c249a Assert CPubKey::ValidLength to the pubkey's header-relevent size (Ben Woosley)

Pull request description:

  A pubkey's length is specific to its type which is indicated by its header value. GetLen returns the header-indicated length, so this change ensures that a key matches its header-indicated length.

  And replace some magic values with their constant equivalents.

Tree-SHA512: b727b39a631babe0932326396fc4d796ade8ec1e37454ff0c709ae9b78ecbd0cfdf59d84089ba8415e6efa7bc180e3cd39a14ddaf0871cbac54b96851e1b7b44

Author: MarcoFalke

src/script/interpreter.cpp

@@ -84,7 +84,7 @@ bool static IsCompressedOrUncompressedPubKey(const valtype &vchPubKey) {
 }
 
 bool static IsCompressedPubKey(const valtype &vchPubKey) {
-    if (vchPubKey.size() != 33) {
+    if (vchPubKey.size() != CPubKey::COMPRESSED_PUBLIC_KEY_SIZE) {
         //  Non-canonical public key: invalid length for compressed key
         return false;
     }