From 5ee8a9b306c3c8c08e55911e921cd688870950cd Mon Sep 17 00:00:00 2001
From: Christopher Jeffrey <chjjeffrey@gmail.com>
Date: Wed, 15 Mar 2017 04:49:54 -0700
Subject: [PATCH] rpc: improve gbt proposal and capabilities handling.

---
 lib/http/rpc.js     | 56 ++++++++++++++++++++++++++++++++++-----------
 lib/http/rpcbase.js | 54 +++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 97 insertions(+), 13 deletions(-)

diff --git a/lib/http/rpc.js b/lib/http/rpc.js
index 8734d77c..01988518 100644
--- a/lib/http/rpc.js
+++ b/lib/http/rpc.js
@@ -32,6 +32,7 @@ var Validator = require('../utils/validator');
 var RPCBase = require('./rpcbase');
 var pkg = require('../pkg');
 var RPCError = RPCBase.RPCError;
+var errs = RPCBase.errors;
 var MAGIC_STRING = RPCBase.MAGIC_STRING;
 
 /**
@@ -1061,7 +1062,9 @@ RPC.prototype.getBlockTemplate = co(function* getBlockTemplate(args, help) {
   var capabilities = valid.array('capabilities');
   var version = valid.u32('maxversion', -1);
   var coinbase = false;
-  var i, cap, block, value, txn;
+  var txnCap = false;
+  var valueCap = false;
+  var i, capability, block;
 
   if (help || args.length > 1)
     throw new RPCError('getblocktemplate ( "jsonrequestobject" )');
@@ -1075,7 +1078,18 @@ RPC.prototype.getBlockTemplate = co(function* getBlockTemplate(args, help) {
 
     block = Block.fromRaw(data);
 
-    return yield this.addBlock(block);
+    if (block.prevBlock !== this.chain.tip.hash)
+      return 'inconclusive-not-best-prevblk';
+
+    try {
+      yield this.chain.verifyBlock(block);
+    } catch (e) {
+      if (e.type === 'VerifyError')
+        return e.reason;
+      throw e;
+    }
+
+    return null;
   }
 
   if (rules)
@@ -1083,21 +1097,29 @@ RPC.prototype.getBlockTemplate = co(function* getBlockTemplate(args, help) {
 
   if (capabilities) {
     for (i = 0; i < capabilities.length; i++) {
-      cap = capabilities[i];
-      switch (cap) {
+      capability = capabilities[i];
+
+      if (typeof capability !== 'string')
+        throw new RPCError('Capability must be a string.');
+
+      switch (capability) {
         case 'coinbasetxn':
-          txn = true;
+          txnCap = true;
           break;
         case 'coinbasevalue':
-          value = true;
+          // Prefer value if they support it.
+          valueCap = true;
           break;
         case 'coinbase/append':
           break;
       }
     }
 
-    if (txn)
+    if (txnCap && !valueCap) {
+      if (this.miner.addresses.length === 0)
+        throw new RPCError('No addresses available for coinbase.');
       coinbase = true;
+    }
   }
 
   if (!this.network.selfConnect) {
@@ -1224,10 +1246,8 @@ RPC.prototype._createTemplate = co(function* _createTemplate(version, coinbase,
     weightlimit: undefined,
     longpollid: this.chain.tip.rhash() + util.pad32(this.totalTX()),
     submitold: false,
-    coinbaseaux: {
-      flags: attempt.coinbaseFlags.toString('hex')
-    },
-    coinbasevalue: attempt.getReward(),
+    coinbaseaux: undefined,
+    coinbasevalue: undefined,
     coinbasetxn: undefined,
     default_witness_commitment: undefined,
     transactions: txs
@@ -1243,11 +1263,16 @@ RPC.prototype._createTemplate = co(function* _createTemplate(version, coinbase,
   if (coinbase) {
     tx = attempt.toCoinbase();
 
-    // We don't include the commitment
-    // output (see bip145).
     if (attempt.witness) {
+      // We don't include the commitment
+      // output (see bip145).
       output = tx.outputs.pop();
       assert(output.script.isCommitment());
+
+      // Also not including the witness nonce.
+      tx.inputs[0].witness.length = 0;
+      tx.inputs[0].witness.compile();
+
       tx.refresh();
     }
 
@@ -1260,6 +1285,11 @@ RPC.prototype._createTemplate = co(function* _createTemplate(version, coinbase,
       sigops: tx.getSigopsCost() / scale | 0,
       weight: tx.getWeight()
     };
+  } else {
+    json.coinbaseaux = {
+      flags: attempt.coinbaseFlags.toString('hex')
+    };
+    json.coinbasevalue = attempt.getReward();
   }
 
   if (rules && rules.indexOf('segwit') !== -1)
diff --git a/lib/http/rpcbase.js b/lib/http/rpcbase.js
index e9e8ef0a..cab7edac 100644
--- a/lib/http/rpcbase.js
+++ b/lib/http/rpcbase.js
@@ -33,6 +33,60 @@ function RPCBase() {
 
 util.inherits(RPCBase, EventEmitter);
 
+/**
+ * RPC errors.
+ * @enum {Number}
+ * @default
+ */
+
+RPCBase.errors = {
+  // Standard JSON-RPC 2.0 errors
+  INVALID_REQUEST: -32600,
+  METHOD_NOT_FOUND: -32601,
+  INVALID_PARAMS: -32602,
+  INTERNAL_ERROR: -32603,
+  PARSE_ERROR: -32700,
+
+  // General application defined errors
+  MISC_ERROR: -1,
+  FORBIDDEN_BY_SAFE_MODE: -2,
+  TYPE_ERROR: -3,
+  INVALID_ADDRESS_OR_KEY: -5,
+  OUT_OF_MEMORY: -7,
+  INVALID_PARAMETER: -8,
+  DATABASE_ERROR: -20,
+  DESERIALIZATION_ERROR: -22,
+  VERIFY_ERROR: -25,
+  VERIFY_REJECTED: -26,
+  VERIFY_ALREADY_IN_CHAIN: -27,
+  IN_WARMUP: -28,
+
+  // Aliases for backward compatibility
+  TRANSACTION_ERROR: -25,
+  TRANSACTION_REJECTED: -26,
+  TRANSACTION_ALREADY_IN_CHAIN: -27,
+
+  // P2P client errors
+  CLIENT_NOT_CONNECTED: -9,
+  CLIENT_IN_INITIAL_DOWNLOAD: -10,
+  CLIENT_NODE_ALREADY_ADDED: -23,
+  CLIENT_NODE_NOT_ADDED: -24,
+  CLIENT_NODE_NOT_CONNECTED: -29,
+  CLIENT_INVALID_IP_OR_SUBNET: -30,
+  CLIENT_P2P_DISABLED: -31,
+
+  // Wallet errors
+  WALLET_ERROR: -4,
+  WALLET_INSUFFICIENT_FUNDS: -6,
+  WALLET_INVALID_ACCOUNT_NAME: -11,
+  WALLET_KEYPOOL_RAN_OUT: -12,
+  WALLET_UNLOCK_NEEDED: -13,
+  WALLET_PASSPHRASE_INCORRECT: -14,
+  WALLET_WRONG_ENC_STATE: -15,
+  WALLET_ENCRYPTION_FAILED: -16,
+  WALLET_ALREADY_UNLOCKED: -17
+};
+
 /**
  * Magic string for signing.
  * @const {String}