From d5756faef46417bd7106c7285a2b22bf00e7faf3 Mon Sep 17 00:00:00 2001
From: Dirk Zimoch <dirk.zimoch@psi.ch>
Date: Thu, 19 May 2022 09:07:31 +0200
Subject: [PATCH] restore compatibility with EPICS 3.13 clients

---
 modules/database/src/ioc/rsrv/camessage.c | 64 +++++++++++++++++++++--
 1 file changed, 61 insertions(+), 3 deletions(-)

diff --git a/modules/database/src/ioc/rsrv/camessage.c b/modules/database/src/ioc/rsrv/camessage.c
index 21c835b8f..cd5f266c3 100644
--- a/modules/database/src/ioc/rsrv/camessage.c
+++ b/modules/database/src/ioc/rsrv/camessage.c
@@ -280,6 +280,37 @@ static void log_header (
     struct channel_in_use *pciu;
     char hostName[256];
 
+    const char * cmd_str [] = {
+         "CA_PROTO_VERSION",
+         "CA_PROTO_EVENT_ADD",
+         "CA_PROTO_EVENT_CANCEL",
+         "CA_PROTO_READ",
+         "CA_PROTO_WRITE",
+         "CA_PROTO_SNAPSHOT",
+         "CA_PROTO_SEARCH",
+         "CA_PROTO_BUILD",
+         "CA_PROTO_EVENTS_OFF",
+         "CA_PROTO_EVENTS_ON",
+         "CA_PROTO_READ_SYNC",
+         "CA_PROTO_ERROR",
+         "CA_PROTO_CLEAR_CHANNEL",
+         "CA_PROTO_RSRV_IS_UP",
+         "CA_PROTO_NOT_FOUND",
+         "CA_PROTO_READ_NOTIFY",
+         "CA_PROTO_READ_BUILD",
+         "REPEATER_CONFIRM",
+         "CA_PROTO_CREATE_CHAN",
+         "CA_PROTO_WRITE_NOTIFY",
+         "CA_PROTO_CLIENT_NAME",
+         "CA_PROTO_HOST_NAME",
+         "CA_PROTO_ACCESS_RIGHTS",
+         "CA_PROTO_ECHO",
+         "REPEATER_REGISTER",
+         "CA_PROTO_SIGNAL",
+         "CA_PROTO_CREATE_CH_FAIL",
+         "CA_PROTO_SERVER_DISCONN"
+    };
+
     ipAddrToDottedIP (&client->addr, hostName, sizeof(hostName));
 
     pciu = MPTOPCIU(mp);
@@ -289,8 +320,10 @@ static void log_header (
             hostName, pContext);
     }
 
-    epicsPrintf ( "CAS: Request from %s => cmmd=%d cid=0x%x type=%d count=%d postsize=%u\n",
-        hostName, mp->m_cmmd, mp->m_cid, mp->m_dataType, mp->m_count, mp->m_postsize);
+    epicsPrintf ( "CAS: %s Request from %s => cmmd=%d (%s) cid=0x%x type=%d count=%d postsize=%u version=%u\n",
+        client->proto==IPPROTO_TCP ? "TCP" : "UDP",
+        hostName, mp->m_cmmd, mp->m_cmmd <= CA_PROTO_LAST_CMMD ? cmd_str[mp->m_cmmd] : "invalid",
+        mp->m_cid, mp->m_dataType, mp->m_count, mp->m_postsize, client->minor_version_number);
 
     epicsPrintf ( "CAS: Request from %s =>   available=0x%x \tN=%u paddr=%p\n",
         hostName, mp->m_available, mnum, (pciu ? (void *)&pciu->dbch : NULL));
@@ -319,6 +352,18 @@ unsigned            lineno
     SEND_UNLOCK ( client );
 }
 
+/*
+ * bad_udp_cmd_beacon()
+ */
+static int bad_udp_cmd_beacon ( caHdrLargeArray *mp,
+                       void *pPayload, struct client *pClient )
+{
+    if (CASDEBUG > 0)
+        log_header ("got a beacon on the wrong UDP port",
+                    pClient, mp, pPayload, 0);
+    return RSRV_ERROR;
+}
+
 /*
  * bad_udp_cmd_action()
  */
@@ -363,6 +408,8 @@ static int tcp_version_action ( caHdrLargeArray *mp, void *pPayload,
 
     client->minor_version_number = mp->m_count;
 
+    DLOG(3, ("TCP set version %u\n", client->minor_version_number));
+
     if (!CA_VSUPPORTED(mp->m_count)) {
         DLOG ( 2, ( "CAS: Ignore version from unsupported client %u\n", mp->m_count ) );
         return RSRV_ERROR;
@@ -1213,6 +1260,7 @@ static int claim_ciu_action ( caHdrLargeArray *mp,
     struct dbChannel *dbch;
     char *pName = (char *) pPayload;
 
+    DLOG (3, ("claim_ciu_action: version = %u\n", mp->m_available));
     /*
      * The available field is used (abused)
      * here to communicate the miner version number
@@ -2121,6 +2169,8 @@ static int udp_version_action ( caHdrLargeArray *mp, void *pPayload, struct clie
 {
     client->minor_version_number = mp->m_count;
 
+    DLOG (3, ("UDP set version %u\n", client->minor_version_number));
+
     if (!CA_VSUPPORTED(mp->m_count)) {
         DLOG ( 2, ( "CAS: Ignore version from unsupported client %u\n", mp->m_count ) );
         return RSRV_ERROR;
@@ -2174,6 +2224,9 @@ static int search_reply_udp ( caHdrLargeArray *mp, void *pPayload, struct client
     size_t          spaceNeeded;
     size_t          reasonableMonitorSpace = 10;
 
+    DLOG (3, epicsPrintf("UDP search for \"%.*s\" by %s@%s client version %u, m_count = %u\n",
+        mp->m_postsize, pName, client->pUserName, client->pHostName, client->minor_version_number, mp->m_count));
+
     if (!CA_VSUPPORTED(mp->m_count)) {
         DLOG ( 2, ( "CAS: Ignore search from unsupported client %u\n", mp->m_count ) );
         return RSRV_ERROR;
@@ -2261,6 +2314,9 @@ static int search_reply_tcp (
     size_t          spaceNeeded;
     size_t          reasonableMonitorSpace = 10;
 
+    DLOG (3, ("TCP search for \"%.*s\" by %s@%s client version %u, m_count = %u\n",
+        mp->m_postsize, pName, client->pUserName, client->pHostName, client->minor_version_number, mp->m_count));
+
     if (!CA_VSUPPORTED(mp->m_count)) {
         DLOG ( 2, ( "CAS: Ignore search from unsupported client %u\n", mp->m_count ) );
         return RSRV_ERROR;
@@ -2368,7 +2424,7 @@ static const pProtoStubUDP udpJumpTable[] =
     bad_udp_cmd_action,
     bad_udp_cmd_action,
     bad_udp_cmd_action,
-    bad_udp_cmd_action,
+    bad_udp_cmd_beacon,
     bad_udp_cmd_action,
     bad_udp_cmd_action,
     bad_udp_cmd_action,
@@ -2449,6 +2505,7 @@ int camessage ( struct client *client )
             pBody = ( void * ) ( mp + 1 );
         }
 
+#if 0
         /* ignore deprecated clients, but let newer clients identify themselves. */
         if (msg.m_cmmd!=CA_PROTO_VERSION && !CA_VSUPPORTED(client->minor_version_number)) {
             if (client->proto==IPPROTO_TCP) {
@@ -2470,6 +2527,7 @@ int camessage ( struct client *client )
             }
             break;
         }
+#endif
 
         /*
          * disconnect clients that dont send 8 byte