From 5a0d0a17178816f9cb274c08f0ec79643d7b394d Mon Sep 17 00:00:00 2001
From: alesapin <alesapin@gmail.com>
Date: Mon, 17 May 2021 18:31:44 +0300
Subject: [PATCH 1/4] Much simplier isLocalAddress

---
 src/Common/isLocalAddress.cpp | 75 +++++++++++++++++++++++++++++------
 1 file changed, 63 insertions(+), 12 deletions(-)

diff --git a/src/Common/isLocalAddress.cpp b/src/Common/isLocalAddress.cpp
index 8da281e3051..741942a877b 100644
--- a/src/Common/isLocalAddress.cpp
+++ b/src/Common/isLocalAddress.cpp
@@ -1,29 +1,80 @@
 #include <Common/isLocalAddress.h>
 
+#include <ifaddrs.h>
 #include <cstring>
 #include <common/types.h>
+#include <Common/Exception.h>
 #include <Poco/Util/Application.h>
 #include <Poco/Net/NetworkInterface.h>
+#include <Poco/Net/IPAddress.h>
 #include <Poco/Net/SocketAddress.h>
 
 
 namespace DB
 {
 
+namespace ErrorCodes
+{
+    extern const int SYSTEM_ERROR;
+}
+
+namespace
+{
+
+struct NetworkInterfaces
+{
+    ifaddrs * ifaddr;
+    NetworkInterfaces()
+    {
+        if (getifaddrs(&ifaddr) == -1)
+        {
+            throwFromErrno("Cannot getifaddrs", ErrorCodes::SYSTEM_ERROR);
+        }
+    }
+
+    bool hasAddress(const Poco::Net::IPAddress & address) const
+    {
+        ifaddrs * iface;
+        for (iface = ifaddr; iface != nullptr; iface = iface->ifa_next)
+        {
+			auto family = iface->ifa_addr->sa_family;
+            std::optional<Poco::Net::IPAddress> interface_address;
+            switch (family)
+            {
+                /// We interested only in IP-adresses
+                case AF_INET:
+                {
+				    interface_address.emplace(*(iface->ifa_addr));
+                    break;
+                }
+                case AF_INET6:
+                {
+				    interface_address.emplace(&reinterpret_cast<const struct sockaddr_in6*>(iface->ifa_addr)->sin6_addr, sizeof(struct in6_addr));
+                    break;
+                }
+                default:
+                    continue;
+            }
+            if (interface_address->length() == address.length()
+                && 0 == memcmp(interface_address->addr(), address.addr(), address.length()))
+                return true;
+        }
+        return false;
+    }
+
+    ~NetworkInterfaces()
+    {
+        freeifaddrs(ifaddr);
+    }
+};
+
+}
+
+
 bool isLocalAddress(const Poco::Net::IPAddress & address)
 {
-    static auto interfaces = Poco::Net::NetworkInterface::list();
-
-    return interfaces.end() != std::find_if(interfaces.begin(), interfaces.end(),
-                [&] (const Poco::Net::NetworkInterface & interface)
-                {
-                    /** Compare the addresses without taking into account `scope`.
-                      * Theoretically, this may not be correct - depends on `route` setting
-                      *  - through which interface we will actually access the specified address.
-                      */
-                    return interface.address().length() == address.length()
-                        && 0 == memcmp(interface.address().addr(), address.addr(), address.length());
-                });
+    NetworkInterfaces interfaces;
+    return interfaces.hasAddress(address);
 }
 
 bool isLocalAddress(const Poco::Net::SocketAddress & address, UInt16 clickhouse_port)

From b4f07a017c1342fce68d088927cfdda199193c22 Mon Sep 17 00:00:00 2001
From: alesapin <alesapin@gmail.com>
Date: Mon, 17 May 2021 18:32:34 +0300
Subject: [PATCH 2/4] Space

---
 src/Common/isLocalAddress.cpp | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/Common/isLocalAddress.cpp b/src/Common/isLocalAddress.cpp
index 741942a877b..60de569dffe 100644
--- a/src/Common/isLocalAddress.cpp
+++ b/src/Common/isLocalAddress.cpp
@@ -55,6 +55,7 @@ struct NetworkInterfaces
                 default:
                     continue;
             }
+
             if (interface_address->length() == address.length()
                 && 0 == memcmp(interface_address->addr(), address.addr(), address.length()))
                 return true;

From acaf260a2ec8c75171667459968019d674c8948f Mon Sep 17 00:00:00 2001
From: alesapin <alesapin@gmail.com>
Date: Mon, 17 May 2021 19:18:38 +0300
Subject: [PATCH 3/4] Better

---
 src/Common/isLocalAddress.cpp | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/src/Common/isLocalAddress.cpp b/src/Common/isLocalAddress.cpp
index 60de569dffe..894f61cae65 100644
--- a/src/Common/isLocalAddress.cpp
+++ b/src/Common/isLocalAddress.cpp
@@ -4,8 +4,6 @@
 #include <cstring>
 #include <common/types.h>
 #include <Common/Exception.h>
-#include <Poco/Util/Application.h>
-#include <Poco/Net/NetworkInterface.h>
 #include <Poco/Net/IPAddress.h>
 #include <Poco/Net/SocketAddress.h>
 
@@ -37,19 +35,19 @@ struct NetworkInterfaces
         ifaddrs * iface;
         for (iface = ifaddr; iface != nullptr; iface = iface->ifa_next)
         {
-			auto family = iface->ifa_addr->sa_family;
+            auto family = iface->ifa_addr->sa_family;
             std::optional<Poco::Net::IPAddress> interface_address;
             switch (family)
             {
                 /// We interested only in IP-adresses
                 case AF_INET:
                 {
-				    interface_address.emplace(*(iface->ifa_addr));
+                    interface_address.emplace(*(iface->ifa_addr));
                     break;
                 }
                 case AF_INET6:
                 {
-				    interface_address.emplace(&reinterpret_cast<const struct sockaddr_in6*>(iface->ifa_addr)->sin6_addr, sizeof(struct in6_addr));
+                    interface_address.emplace(&reinterpret_cast<const struct sockaddr_in6*>(iface->ifa_addr)->sin6_addr, sizeof(struct in6_addr));
                     break;
                 }
                 default:

From 6127ba901e75bf65025d8a04cb92491b8ae14676 Mon Sep 17 00:00:00 2001
From: alesapin <alesapin@gmail.com>
Date: Mon, 17 May 2021 19:29:11 +0300
Subject: [PATCH 4/4] Small improvements

---
 src/Common/isLocalAddress.cpp | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/Common/isLocalAddress.cpp b/src/Common/isLocalAddress.cpp
index 894f61cae65..cecff489a22 100644
--- a/src/Common/isLocalAddress.cpp
+++ b/src/Common/isLocalAddress.cpp
@@ -2,6 +2,7 @@
 
 #include <ifaddrs.h>
 #include <cstring>
+#include <optional>
 #include <common/types.h>
 #include <Common/Exception.h>
 #include <Poco/Net/IPAddress.h>
@@ -54,6 +55,10 @@ struct NetworkInterfaces
                     continue;
             }
 
+            /** Compare the addresses without taking into account `scope`.
+              * Theoretically, this may not be correct - depends on `route` setting
+              *  - through which interface we will actually access the specified address.
+              */
             if (interface_address->length() == address.length()
                 && 0 == memcmp(interface_address->addr(), address.addr(), address.length()))
                 return true;