Merge branch 'msantos/epmd-IPv6-node-reg2/PR-864/OTP-13364' into maint

* msantos/epmd-IPv6-node-reg2/PR-864/OTP-13364:
  epmd: support IPv6 node registration

1 files changed, 142 insertions, 59 deletions

diff --git a/erts/epmd/src/epmd_srv.c b/erts/epmd/src/epmd_srv.c
index 7100855407..55ec0f7b6c 100644
--- a/erts/epmd/src/epmd_srv.c
+++ b/erts/epmd/src/epmd_srv.c
@@ -76,6 +76,7 @@ static time_t current_time(EpmdVars*);
 
 static Connection *conn_init(EpmdVars*);
 static int conn_open(EpmdVars*,int);
+static int conn_local_peer_check(EpmdVars*, int);
 static int conn_close_fd(EpmdVars*,int);
 
 static void node_init(EpmdVars*);
@@ -206,10 +207,11 @@ void run(EpmdVars *g)
 {
   struct EPMD_SOCKADDR_IN iserv_addr[MAX_LISTEN_SOCKETS];
   int listensock[MAX_LISTEN_SOCKETS];
-  int num_sockets;
+  int num_sockets = 0;
   int i;
   int opt;
   unsigned short sport = g->port;
+  int bound = 0;
 
   node_init(g);
   g->conn = conn_init(g);
@@ -252,64 +254,82 @@ void run(EpmdVars *g)
   if (g->addresses != NULL && /* String contains non-separator characters if: */
       g->addresses[strspn(g->addresses," ,")] != '\000')
     {
-      char *tmp;
-      char *token;
-      int loopback_ok = 0;
+      char *tmp = NULL;
+      char *token = NULL;
+
+      /* Always listen on the loopback. */
+      SET_ADDR(iserv_addr[num_sockets],htonl(INADDR_LOOPBACK),sport);
+      num_sockets++;
+#if defined(EPMD6)
+      SET_ADDR6(iserv_addr[num_sockets],in6addr_loopback,sport);
+      num_sockets++;
+#endif
 
-      if ((tmp = (char *)malloc(strlen(g->addresses) + 1)) == NULL)
+	  if ((tmp = strdup(g->addresses)) == NULL)
 	{
 	  dbg_perror(g,"cannot allocate memory");
 	  epmd_cleanup_exit(g,1);
 	}
-      strcpy(tmp,g->addresses);
 
-      for(token = strtok(tmp,", "), num_sockets = 0;
+      for(token = strtok(tmp,", ");
 	  token != NULL;
-	  token = strtok(NULL,", "), num_sockets++)
+	  token = strtok(NULL,", "))
 	{
-	  struct EPMD_IN_ADDR addr;
-#ifdef HAVE_INET_PTON
-	  int ret;
+	  struct in_addr addr;
+#if defined(EPMD6)
+	  struct in6_addr addr6;
+	  struct sockaddr_storage *sa = &iserv_addr[num_sockets];
 
-	  if ((ret = inet_pton(FAMILY,token,&addr)) == -1)
+	  if (inet_pton(AF_INET6,token,&addr6) == 1)
 	    {
-	      dbg_perror(g,"cannot convert IP address to network format");
-	      epmd_cleanup_exit(g,1);
+	      SET_ADDR6(iserv_addr[num_sockets],addr6,sport);
+	    }
+	  else if (inet_pton(AF_INET,token,&addr) == 1)
+	    {
+	      SET_ADDR(iserv_addr[num_sockets],addr.s_addr,sport);
+	    }
+	  else
+#else
+	  if ((addr.s_addr = inet_addr(token)) != INADDR_NONE)
+	    {
+	      SET_ADDR(iserv_addr[num_sockets],addr.s_addr,sport);
 	    }
-	  else if (ret == 0)
-#elif !defined(EPMD6)
-	  if ((addr.EPMD_S_ADDR = inet_addr(token)) == INADDR_NONE)
+	  else
 #endif
 	    {
 	      dbg_tty_printf(g,0,"cannot parse IP address \"%s\"",token);
 	      epmd_cleanup_exit(g,1);
 	    }
 
+#if defined(EPMD6)
+	  if (sa->ss_family == AF_INET6 && IN6_IS_ADDR_LOOPBACK(&addr6))
+	      continue;
+
+	  if (sa->ss_family == AF_INET)
+#endif
 	  if (IS_ADDR_LOOPBACK(addr))
-	    loopback_ok = 1;
+	    continue;
+
+	  num_sockets++;
 
-	  if (num_sockets - loopback_ok == MAX_LISTEN_SOCKETS - 1)
+	  if (num_sockets >= MAX_LISTEN_SOCKETS)
 	    {
 	      dbg_tty_printf(g,0,"cannot listen on more than %d IP addresses",
 			     MAX_LISTEN_SOCKETS);
 	      epmd_cleanup_exit(g,1);
 	    }
-
-	  SET_ADDR(iserv_addr[num_sockets],addr.EPMD_S_ADDR,sport);
 	}
 
       free(tmp);
-
-      if (!loopback_ok)
-	{
-	  SET_ADDR(iserv_addr[num_sockets],EPMD_ADDR_LOOPBACK,sport);
-	  num_sockets++;
-	}
     }
   else
     {
-      SET_ADDR(iserv_addr[0],EPMD_ADDR_ANY,sport);
-      num_sockets = 1;
+      SET_ADDR(iserv_addr[num_sockets],htonl(INADDR_ANY),sport);
+      num_sockets++;
+#if defined(EPMD6)
+      SET_ADDR6(iserv_addr[num_sockets],in6addr_any,sport);
+      num_sockets++;
+#endif
     }
 #ifdef HAVE_SYSTEMD_DAEMON
     }
@@ -340,13 +360,39 @@ void run(EpmdVars *g)
 #endif /* HAVE_SYSTEMD_DAEMON */
   for (i = 0; i < num_sockets; i++)
     {
-      if ((listensock[i] = socket(FAMILY,SOCK_STREAM,0)) < 0)
+      struct sockaddr *sa = (struct sockaddr *)&iserv_addr[i];
+#if defined(EPMD6)
+      size_t salen = (sa->sa_family == AF_INET6 ?
+              sizeof(struct sockaddr_in6) :
+              sizeof(struct sockaddr_in));
+#else
+      size_t salen = sizeof(struct sockaddr_in);
+#endif
+
+      if ((listensock[i] = socket(sa->sa_family,SOCK_STREAM,0)) < 0)
 	{
-	  dbg_perror(g,"error opening stream socket");
-	  epmd_cleanup_exit(g,1);
+	  switch (errno) {
+	      case EAFNOSUPPORT:
+	      case EPROTONOSUPPORT:
+	          continue;
+	      default:
+	          dbg_perror(g,"error opening stream socket");
+	          epmd_cleanup_exit(g,1);
+	  }
 	}
       g->listenfd[i] = listensock[i];
-  
+
+#if HAVE_DECL_IPV6_V6ONLY
+      opt = 1;
+      if (sa->sa_family == AF_INET6 &&
+          setsockopt(listensock[i],IPPROTO_IPV6,IPV6_V6ONLY,&opt,
+              sizeof(opt)) <0)
+	{
+	  dbg_perror(g,"can't set IPv6 only socket option");
+	  epmd_cleanup_exit(g,1);
+	}
+#endif
+
       /*
        * Note that we must not enable the SO_REUSEADDR on Windows,
        * because addresses will be reused even if they are still in use.
@@ -378,8 +424,7 @@ void run(EpmdVars *g)
 	dbg_perror(g,"failed to set non-blocking mode of listening socket %d",
 		   listensock[i]);
 
-      if (bind(listensock[i], (struct sockaddr*) &iserv_addr[i],
-	  sizeof(iserv_addr[i])) < 0)
+      if (bind(listensock[i], (struct sockaddr*) &iserv_addr[i], salen) < 0)
 	{
 	  if (errno == EADDRINUSE)
 	    {
@@ -394,12 +439,18 @@ void run(EpmdVars *g)
 	    }
 	}
 
+      bound++;
+
       if(listen(listensock[i], SOMAXCONN) < 0) {
           dbg_perror(g,"failed to listen on socket");
           epmd_cleanup_exit(g,1);
       }
       select_fd_set(g, listensock[i]);
     }
+  if (bound == 0) {
+      dbg_perror(g,"unable to bind any address");
+      epmd_cleanup_exit(g,1);
+  }
 #ifdef HAVE_SYSTEMD_DAEMON
     }
     sd_notifyf(0, "READY=1\n"
@@ -1005,15 +1056,6 @@ static int conn_open(EpmdVars *g,int fd)
 
   for (i = 0; i < g->max_conn; i++) {
     if (g->conn[i].open == EPMD_FALSE) {
-      struct sockaddr_in si;
-      struct sockaddr_in di;
-#ifdef HAVE_SOCKLEN_T
-      socklen_t st;
-#else
-      int st;
-#endif
-      st = sizeof(si);
-
       g->active_conn++;
       s = &g->conn[i];
      
@@ -1024,20 +1066,7 @@ static int conn_open(EpmdVars *g,int fd)
       s->open = EPMD_TRUE;
       s->keep = EPMD_FALSE;
 
-      /* Determine if connection is from localhost */
-      if (getpeername(s->fd,(struct sockaddr*) &si,&st) ||
-	  st < sizeof(si)) {
-	  /* Failure to get peername is regarded as non local host */
-	  s->local_peer = EPMD_FALSE;
-      } else {
-	  /* Only 127.x.x.x and connections from the host's IP address
-	     allowed, no false positives */
-	  s->local_peer =
-	      (((((unsigned) ntohl(si.sin_addr.s_addr)) & 0xFF000000U) ==
-	       0x7F000000U) ||
-	       (getsockname(s->fd,(struct sockaddr*) &di,&st) ?
-	       EPMD_FALSE : si.sin_addr.s_addr == di.sin_addr.s_addr));
-      }
+      s->local_peer = conn_local_peer_check(g, s->fd);
       dbg_tty_printf(g,2,(s->local_peer) ? "Local peer connected" :
 		     "Non-local peer connected");
 
@@ -1045,7 +1074,7 @@ static int conn_open(EpmdVars *g,int fd)
       s->got  = 0;
       s->mod_time = current_time(g); /* Note activity */
 
-      s->buf = (char *)malloc(INBUF_SIZE);
+      s->buf = malloc(INBUF_SIZE);
 
       if (s->buf == NULL) {
 	dbg_printf(g,0,"epmd: Insufficient memory");
@@ -1063,6 +1092,60 @@ static int conn_open(EpmdVars *g,int fd)
   return EPMD_FALSE;
 }
 
+static int conn_local_peer_check(EpmdVars *g, int fd)
+{
+  struct EPMD_SOCKADDR_IN si;
+  struct EPMD_SOCKADDR_IN di;
+
+  struct sockaddr_in *si4 = (struct sockaddr_in *)&si;
+  struct sockaddr_in *di4 = (struct sockaddr_in *)&di;
+
+#if defined(EPMD6)
+  struct sockaddr_in6 *si6 = (struct sockaddr_in6 *)&si;
+  struct sockaddr_in6 *di6 = (struct sockaddr_in6 *)&di;
+#endif
+
+#ifdef HAVE_SOCKLEN_T
+  socklen_t st;
+#else
+  int st;
+#endif
+
+  st = sizeof(si);
+
+  /* Determine if connection is from localhost */
+  if (getpeername(fd,(struct sockaddr*) &si,&st) ||
+	  st > sizeof(si)) {
+	  /* Failure to get peername is regarded as non local host */
+	  return EPMD_FALSE;
+  }
+
+  /* Only 127.x.x.x and connections from the host's IP address
+	 allowed, no false positives */
+#if defined(EPMD6)
+  if (si.ss_family == AF_INET6 && IN6_IS_ADDR_LOOPBACK(&(si6->sin6_addr)))
+	  return EPMD_TRUE;
+
+  if (si.ss_family == AF_INET)
+#endif
+  if ((((unsigned) ntohl(si4->sin_addr.s_addr)) & 0xFF000000U) ==
+	  0x7F000000U)
+	  return EPMD_TRUE;
+
+  if (getsockname(fd,(struct sockaddr*) &di,&st))
+	  return EPMD_FALSE;
+
+#if defined(EPMD6)
+  if (si.ss_family == AF_INET6)
+      return IN6_ARE_ADDR_EQUAL( &(si6->sin6_addr), &(di6->sin6_addr));
+  if (si.ss_family == AF_INET)
+#endif
+  return si4->sin_addr.s_addr == di4->sin_addr.s_addr;
+#if defined(EPMD6)
+  return EPMD_FALSE;
+#endif
+}
+
 static int conn_close_fd(EpmdVars *g,int fd)
 {
   int i;