1 files changed, 36 insertions, 7 deletions

diff --git a/src/zmq/zmqpublishnotifier.cpp b/src/zmq/zmqpublishnotifier.cpp
index 168ba841c8..2c6f24a239 100644
--- a/src/zmq/zmqpublishnotifier.cpp
+++ b/src/zmq/zmqpublishnotifier.cpp
@@ -1,4 +1,4 @@
-// Copyright (c) 2015-2020 The Bitcoin Core developers
+// Copyright (c) 2015-2021 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
@@ -6,10 +6,12 @@
 
 #include <chain.h>
 #include <chainparams.h>
+#include <netbase.h>
+#include <node/blockstorage.h>
 #include <rpc/server.h>
 #include <streams.h>
 #include <util/system.h>
-#include <validation.h>
+#include <validation.h> // For cs_main
 #include <zmq/zmqutil.h>
 
 #include <zmq.h>
@@ -21,6 +23,8 @@
 #include <string>
 #include <utility>
 
+using node::ReadBlockFromDisk;
+
 static std::multimap<std::string, CZMQAbstractPublishNotifier*> mapPublishNotifiers;
 
 static const char *MSG_HASHBLOCK = "hashblock";
@@ -72,6 +76,20 @@ static int zmq_send_multipart(void *sock, const void* data, size_t size, ...)
     return 0;
 }
 
+static bool IsZMQAddressIPV6(const std::string &zmq_address)
+{
+    const std::string tcp_prefix = "tcp://";
+    const size_t tcp_index = zmq_address.rfind(tcp_prefix);
+    const size_t colon_index = zmq_address.rfind(":");
+    if (tcp_index == 0 && colon_index != std::string::npos) {
+        const std::string ip = zmq_address.substr(tcp_prefix.length(), colon_index - tcp_prefix.length());
+        CNetAddr addr;
+        LookupHost(ip, addr, false);
+        if (addr.IsIPv6()) return true;
+    }
+    return false;
+}
+
 bool CZMQAbstractPublishNotifier::Initialize(void *pcontext)
 {
     assert(!psocket);
@@ -106,6 +124,15 @@ bool CZMQAbstractPublishNotifier::Initialize(void *pcontext)
             return false;
         }
 
+        // On some systems (e.g. OpenBSD) the ZMQ_IPV6 must not be enabled, if the address to bind isn't IPv6
+        const int enable_ipv6 { IsZMQAddressIPV6(address) ? 1 : 0};
+        rc = zmq_setsockopt(psocket, ZMQ_IPV6, &enable_ipv6, sizeof(enable_ipv6));
+        if (rc != 0) {
+            zmqError("Failed to set ZMQ_IPV6");
+            zmq_close(psocket);
+            return false;
+        }
+
         rc = zmq_bind(psocket, address.c_str());
         if (rc != 0)
         {
@@ -167,7 +194,7 @@ bool CZMQAbstractPublishNotifier::SendZmqMessage(const char *command, const void
 
     /* send three parts, command & data & a LE 4byte sequence number */
     unsigned char msgseq[sizeof(uint32_t)];
-    WriteLE32(&msgseq[0], nSequence);
+    WriteLE32(msgseq, nSequence);
     int rc = zmq_send_multipart(psocket, command, strlen(command), data, size, msgseq, (size_t)sizeof(uint32_t), nullptr);
     if (rc == -1)
         return false;
@@ -182,9 +209,10 @@ bool CZMQPublishHashBlockNotifier::NotifyBlock(const CBlockIndex *pindex)
 {
     uint256 hash = pindex->GetBlockHash();
     LogPrint(BCLog::ZMQ, "zmq: Publish hashblock %s to %s\n", hash.GetHex(), this->address);
-    char data[32];
-    for (unsigned int i = 0; i < 32; i++)
+    uint8_t data[32];
+    for (unsigned int i = 0; i < 32; i++) {
         data[31 - i] = hash.begin()[i];
+    }
     return SendZmqMessage(MSG_HASHBLOCK, data, 32);
 }
 
@@ -192,9 +220,10 @@ bool CZMQPublishHashTransactionNotifier::NotifyTransaction(const CTransaction &t
 {
     uint256 hash = transaction.GetHash();
     LogPrint(BCLog::ZMQ, "zmq: Publish hashtx %s to %s\n", hash.GetHex(), this->address);
-    char data[32];
-    for (unsigned int i = 0; i < 32; i++)
+    uint8_t data[32];
+    for (unsigned int i = 0; i < 32; i++) {
         data[31 - i] = hash.begin()[i];
+    }
     return SendZmqMessage(MSG_HASHTX, data, 32);
 }