heartbeat

commit 67211e6cd7818f8a91c76063a6ae49110be20319
parent f966b137279ee388aef1422f0f26724d0dabfaa2
Author: Remy Noulin <loader2x@gmail.com>
Date:   Sun, 23 Jul 2023 08:31:03 +0200

check used port with /proc/net/tcp instead of bind

when bind is not good because it prevents the real server from starting
when heartbeat binds to the port.

heartbeat.c | 52 +++++++++++++++++++++++++++++++++++++---------------
1 file changed, 37 insertions(+), 15 deletions(-)

Diffstat:
M
heartbeat.c
 | 
52
+++++++++++++++++++++++++++++++++++++---------------

1 file changed, 37 insertions(+), 15 deletions(-)
diff --git a/heartbeat.c b/heartbeat.c
@@ -869,23 +869,45 @@ void probe(char *cfgfile, char *secretFile, char *publicFile, char *loggerPublic
           logE("Invalid probe at index %d", iI(probes));
           XFailure;
         }
+        // check all used ports tcp and tcp6
+        staticBitsetT(usedPortst, u64 , 65536);
+        usedPortst usedPorts;
+        staticBitsetInit(&usedPorts);
+        cleanAllocateSmallArray(tcp);
+        readFileG(tcp, "/proc/net/tcp");
+        delElemG(tcp, 0);
+        iter(tcp, L) {
+          castS(l, L);
+          //    0: 00000000:0016 00000000:0000 0A 00000000:00000000 00:00000000 00000000     0        0 14737 1 ffff8d88f5265800 100 0 0 10 0
+          cleanSmallArrayP(ll) = splitG(l, ' ');
+          compactG(ll);
+          //logVarG(ll);
+          char *localAddr = $(ll, 1);
+          char *portStart = localAddr + 8;
+          *portStart      = 'x';
+          u16 port        = parseHex(portStart-1);
+          //logVarG(port);
+          staticBitset1(&usedPorts, port);
+        }
+        emptyG(tcp);
+        readFileG(tcp, "/proc/net/tcp6");
+        delElemG(tcp, 0);
+        iter(tcp, L) {
+          castS(l, L);
+          //    0: 00000000000000000000000000000000:0050 00000000000000000000000000000000:0000 0A 00000000:00000000 00:00000000 00000000     0        0 12592 1 ffff8d88f6b7c940 100 0 0 10 0
+          cleanSmallArrayP(ll) = splitG(l, ' ');
+          compactG(ll);
+          //logVarG(ll);
+          char *localAddr = $(ll, 1);
+          char *portStart = localAddr + 32;
+          *portStart      = 'x';
+          u16 port        = parseHex(portStart-1);
+          //logVarG(port);
+          staticBitset1(&usedPorts, port);
+        }
         if (hasG(p, "port")) {
-          // try to bind
-          int sock = socket(AF_INET, SOCK_STREAM, 0);
-          if (sock < 0){
+          if (not staticBitsetGet(&usedPorts, u$(p, "port")))
             msg.status |= 1UL << iI(probes);
-          }
-          else {
-            struct sockaddr_in server;
-            server.sin_family      = AF_INET;
-            server.sin_addr.s_addr = INADDR_ANY;
-            server.sin_port        = htons((u16)u$(p, "port"));
-            if (bind(sock, (struct sockaddr *) &server, sizeof(server)) == 0) {
-              // bind successful
-              msg.status |= 1UL << iI(probes);
-            }
-            close(sock);
-          }
         }
         elif (hasG(p, "if")) {
           // TODO("check if network interface is down");