From 5b5c01862c0ed3a018f8377e57c0e9fcd5e04cc9 Mon Sep 17 00:00:00 2001
From: Graeme Winter <graeme.winter@gmail.com>
Date: Wed, 11 Dec 2024 15:05:00 +0000
Subject: [PATCH] Explicit bind to correct interface

---
 .../slsDetectorFunctionList.c                 | 14 +++++++++++
 .../include/communication_funcs_UDP.h         |  1 +
 .../src/communication_funcs_UDP.c             | 25 ++++++++++++++++---
 3 files changed, 37 insertions(+), 3 deletions(-)

diff --git a/slsDetectorServers/jungfrauDetectorServer/slsDetectorFunctionList.c b/slsDetectorServers/jungfrauDetectorServer/slsDetectorFunctionList.c
index 39a84eb28c..911c2dd759 100644
--- a/slsDetectorServers/jungfrauDetectorServer/slsDetectorFunctionList.c
+++ b/slsDetectorServers/jungfrauDetectorServer/slsDetectorFunctionList.c
@@ -1715,6 +1715,20 @@ int configureMAC() {
                  src_ip2, src_mac2, srcport2, dst_ip2, dst_mac2, dstport2));
         }
 #ifdef VIRTUAL
+        if (setUDPSourceDetails(iRxEntry, 0, src_ip) == FAIL) {
+            LOG(logERROR, ("could not set udp source IP for "
+                           "interface 1 [entry:%d] \n",
+                           iRxEntry));
+            return FAIL;
+        }
+        if (numInterfaces == 2 &&
+            setUDPSourceDetails(iRxEntry, 1, src_ip2) == FAIL) {
+            LOG(logERROR, ("could not set udp source IP for "
+                           "interface 2 [entry:%d]\n",
+                           iRxEntry));
+            return FAIL;
+        }
+
         if (setUDPDestinationDetails(iRxEntry, 0, dst_ip, dstport) == FAIL) {
             LOG(logERROR, ("could not set udp destination IP and port for "
                            "interface 1 [entry:%d] \n",
diff --git a/slsDetectorServers/slsDetectorServer/include/communication_funcs_UDP.h b/slsDetectorServers/slsDetectorServer/include/communication_funcs_UDP.h
index ecd9d5deb3..f119d530de 100644
--- a/slsDetectorServers/slsDetectorServer/include/communication_funcs_UDP.h
+++ b/slsDetectorServers/slsDetectorServer/include/communication_funcs_UDP.h
@@ -10,6 +10,7 @@ void setNumberOfUDPDestinations(int value);
 
 int setUDPDestinationDetails(int iRxEntry, int index, const char *ip,
                              unsigned short int port);
+int setUDPSourceDetails(int iRxEntry, int index, const char *ip);
 int createUDPSocket(int index);
 
 int sendUDPPacket(int iRxEntry, int index, const char *buf, int length);
diff --git a/slsDetectorServers/slsDetectorServer/src/communication_funcs_UDP.c b/slsDetectorServers/slsDetectorServer/src/communication_funcs_UDP.c
index 1904a1804c..ffa56c457b 100644
--- a/slsDetectorServers/slsDetectorServer/src/communication_funcs_UDP.c
+++ b/slsDetectorServers/slsDetectorServer/src/communication_funcs_UDP.c
@@ -19,6 +19,7 @@ int udpSockfd[MAX_UDP_DESTINATION][2] = {};
 struct addrinfo *udpServerAddrInfo[MAX_UDP_DESTINATION][2] = {};
 unsigned short int udpDestinationPort[MAX_UDP_DESTINATION][2] = {};
 char udpDestinationIp[MAX_UDP_DESTINATION][2][INET_ADDRSTRLEN] = {};
+char udpSourceIp[MAX_UDP_DESTINATION][2][INET_ADDRSTRLEN] = {};
 extern int numUdpDestinations;
 
 void setupUDPCommParameters() {
@@ -28,12 +29,25 @@ void setupUDPCommParameters() {
     }
     memset(udpServerAddrInfo, 0, sizeof(udpServerAddrInfo));
     memset(udpDestinationIp, 0, sizeof(udpDestinationIp));
+    memset(udpSourceIp, 0, sizeof(udpDestinationIp));
 }
 
 int getUdPSocketDescriptor(int iRxEntry, int index) {
     return udpSockfd[iRxEntry][index];
 }
 
+int setUDPSourceDetails(int iRxEntry, int index, const char *ip) {
+    LOG(logDEBUG1,
+        ("Setting udp source details for socket %d [iRxEntry:%d]\n", index,
+         iRxEntry));
+    size_t len = strlen(ip);
+    memset(udpSourceIp[iRxEntry][index], 0, INET_ADDRSTRLEN);
+    strncpy(udpSourceIp[iRxEntry][index], ip,
+            len > INET_ADDRSTRLEN ? INET_ADDRSTRLEN : len);
+
+    return OK;
+}
+
 int setUDPDestinationDetails(int iRxEntry, int index, const char *ip,
                              unsigned short int port) {
     LOG(logDEBUG1,
@@ -86,9 +100,6 @@ int setUDPDestinationDetails(int iRxEntry, int index, const char *ip,
 
 int createUDPSocket(int index) {
 
-
-
-
     int sendbuff;
     socklen_t optlen;
 
@@ -136,6 +147,14 @@ int createUDPSocket(int index) {
         // to these packets connecting allows to use "send/write" instead of
         // "sendto", avoiding checking for server address for each packet using
         // write without a connect will end in segv
+
+        struct sockaddr src_sock;
+        src_sock.sa_family = AF_INET;
+        memcpy(src_sock.sa_data, udpSourceIp[iRxEntry][index], strlen(udpSourceIp[iRxEntry][index]));
+
+        bind(udpSockfd[iRxEntry][index], &src_sock, sizeof(struct sockaddr));
+        LOG(logINFO, ("UDP socket bound to %s\n", udpSourceIp[iRxEntry][index]));
+
         connect(udpSockfd[iRxEntry][index], udpServerAddrInfo[iRxEntry][index]->ai_addr, udpServerAddrInfo[iRxEntry][index]->ai_addrlen);
         LOG(logINFO, ("Udp client socket connected [%d, %d, %s]\n", iRxEntry,
                       udpDestinationPort[iRxEntry][index],