allow multicast socket options IP_MULTICAST_TTL, IP_MULTICAST_IF and IP_MULTICAST_LOOP to be used without IGMP

CHANGELOG

@@ -6,6 +6,10 @@ HISTORY
 
   ++ New features:
 
+  2015-08-05: Simon Goldschmidt
+  * many files: allow multicast socket options IP_MULTICAST_TTL, IP_MULTICAST_IF
+    and IP_MULTICAST_LOOP to be used without IGMP
+
   2015-04-24: Simon Goldschmidt
   * dhcp.h/c, autoip.h/.c: added functions dhcp/autoip_supplied_address() to
     check for the source of address assignemnt (replacement for NETIF_FLAG_DHCP)

src/api/sockets.c

@@ -1830,7 +1830,7 @@ lwip_getsockopt_impl(int s, int level, int optname, void *optval, socklen_t *opt
       LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockopt(%d, IPPROTO_IP, IP_TOS) = %d\n",
                   s, *(int *)optval));
       break;
-#if LWIP_IGMP
+#if LWIP_MULTICAST_TX_OPTIONS
     case IP_MULTICAST_TTL:
       LWIP_SOCKOPT_CHECK_OPTLEN_CONN_PCB(sock, *optlen, u8_t);
       if (NETCONNTYPE_GROUP(netconn_type(sock->conn)) != NETCONN_UDP) {
@@ -1859,7 +1859,7 @@ lwip_getsockopt_impl(int s, int level, int optname, void *optval, socklen_t *opt
       LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockopt(%d, IPPROTO_IP, IP_MULTICAST_LOOP) = %d\n",
                   s, *(int *)optval));
       break;
-#endif /* LWIP_IGMP */
+#endif /* LWIP_MULTICAST_TX_OPTIONS */
     default:
       LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockopt(%d, IPPROTO_IP, UNIMPL: optname=0x%x, ..)\n",
                   s, optname));
@@ -2190,7 +2190,7 @@ lwip_setsockopt_impl(int s, int level, int optname, const void *optval, socklen_
       LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_setsockopt(%d, IPPROTO_IP, IP_TOS, ..)-> %d\n",
                   s, sock->conn->pcb.ip->tos));
       break;
-#if LWIP_IGMP
+#if LWIP_MULTICAST_TX_OPTIONS
     case IP_MULTICAST_TTL:
       LWIP_SOCKOPT_CHECK_OPTLEN_CONN_PCB_TYPE(sock, optlen, u8_t, NETCONN_UDP);
       sock->conn->pcb.udp->mcast_ttl = (u8_t)(*(const u8_t*)optval);
@@ -2211,6 +2211,8 @@ lwip_setsockopt_impl(int s, int level, int optname, const void *optval, socklen_
         udp_setflags(sock->conn->pcb.udp, udp_flags(sock->conn->pcb.udp) & ~UDP_FLAGS_MULTICAST_LOOP);
       }
       break;
+#endif /* LWIP_MULTICAST_TX_OPTIONS */
+#if LWIP_IGMP
     case IP_ADD_MEMBERSHIP:
     case IP_DROP_MEMBERSHIP:
       {

src/core/init.c

@@ -102,6 +102,9 @@
 #if (LWIP_IGMP && (MEMP_NUM_IGMP_GROUP<=1))
   #error "If you want to use IGMP, you have to define MEMP_NUM_IGMP_GROUP>1 in your lwipopts.h"
 #endif
+#if (LWIP_IGMP && !LWIP_MULTICAST_TX_OPTIONS)
+  #error "If you want to use IGMP, you have to define LWIP_MULTICAST_TX_OPTIONS==1 in your lwipopts.h"
+#endif
 #if ((LWIP_NETCONN || LWIP_SOCKET) && (MEMP_NUM_TCPIP_MSG_API<=0))
   #error "If you want to use Sequential API, you have to define MEMP_NUM_TCPIP_MSG_API>=1 in your lwipopts.h"
 #endif

src/core/ipv4/ip4.c

@@ -101,7 +101,7 @@ struct ip_globals ip_data;
 /** The IP header ID of the next outgoing IP packet */
 static u16_t ip_id;
 
-#if LWIP_IGMP
+#if LWIP_MULTICAST_TX_OPTIONS
 /** The default netif used for multicast */
 static struct netif* ip4_default_multicast_netif;
 
@@ -111,7 +111,7 @@ ip4_set_default_multicast_netif(struct netif* default_multicast_netif)
 {
   ip4_default_multicast_netif = default_multicast_netif;
 }
-#endif /* LWIP_IGMP */
+#endif /* LWIP_MULTICAST_TX_OPTIONS */
 
 /**
  * Finds the appropriate network interface for a given IP address. It
@@ -895,11 +895,11 @@ err_t ip4_output_if_opt_src(struct pbuf *p, const ip4_addr_t *src, const ip4_add
     LWIP_DEBUGF(IP_DEBUG, ("netif_loop_output()"));
     return netif_loop_output(netif, p);
   }
-#if LWIP_IGMP
+#if LWIP_MULTICAST_TX_OPTIONS
   if ((p->flags & PBUF_FLAG_MCASTLOOP) != 0) {
     netif_loop_output(netif, p);
   }
-#endif /* LWIP_IGMP */
+#endif /* LWIP_MULTICAST_TX_OPTIONS */
 #endif /* ENABLE_LOOPBACK */
 #if IP_FRAG
   /* don't fragment if interface has mtu set to 0 [loopif] */

src/core/udp.c

@@ -551,13 +551,13 @@ udp_sendto_chksum(struct udp_pcb *pcb, struct pbuf *p, const ip_addr_t *dst_ip,
 #endif /* LWIP_CHECKSUM_ON_COPY && CHECKSUM_GEN_UDP */
   struct netif *netif;
   const ip_addr_t *dst_ip_route = dst_ip;
-#if LWIP_IPV6 && LWIP_IPV4 && LWIP_IGMP
+#if LWIP_IPV6 && LWIP_IPV4 && LWIP_MULTICAST_TX_OPTIONS
   ip_addr_t dst_ip_tmp;
-#endif /* LWIP_IPV6 && LWIP_IPV4 && LWIP_IGMP */
+#endif /* LWIP_IPV6 && LWIP_IPV4 && LWIP_MULTICAST_TX_OPTIONS */
 
   LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE, ("udp_send\n"));
 
-#if LWIP_IPV6 || (LWIP_IPV4 && LWIP_IGMP)
+#if LWIP_IPV6 || (LWIP_IPV4 && LWIP_MULTICAST_TX_OPTIONS)
   if (ip_addr_ismulticast(dst_ip_route)) {
 #if LWIP_IPV6
     if (PCB_ISIPV6(pcb)) {
@@ -566,7 +566,7 @@ udp_sendto_chksum(struct udp_pcb *pcb, struct pbuf *p, const ip_addr_t *dst_ip,
     } else
 #endif /* LWIP_IPV6 */
     {
-#if LWIP_IPV4 && LWIP_IGMP
+#if LWIP_IPV4 && LWIP_MULTICAST_TX_OPTIONS
       /* IPv4 does not use source-based routing by default, so we use an
          administratively selected interface for multicast by default.
          However, this can be overridden by setting an interface address
@@ -575,10 +575,10 @@ udp_sendto_chksum(struct udp_pcb *pcb, struct pbuf *p, const ip_addr_t *dst_ip,
           !ip4_addr_cmp(&pcb->multicast_ip, IP4_ADDR_BROADCAST)) {
         dst_ip_route = ip4_2_ip(&pcb->multicast_ip, &dst_ip_tmp);
       }
-#endif /* LWIP_IPV4 && LWIP_IGMP */
+#endif /* LWIP_IPV4 && LWIP_MULTICAST_TX_OPTIONS */
     }
   }
-#endif /* LWIP_IPV6 || LWIP_IGMP */
+#endif /* LWIP_IPV6 || (LWIP_IPV4 && LWIP_MULTICAST_TX_OPTIONS) */
 
   /* find the outgoing network interface for this packet */
   netif = ip_route(PCB_ISIPV6(pcb), &pcb->local_ip, dst_ip_route);
@@ -758,11 +758,11 @@ udp_sendto_if_src_chksum(struct udp_pcb *pcb, struct pbuf *p, const ip_addr_t *d
   udphdr->chksum = 0x0000;
 
   /* Multicast Loop? */
-#if (LWIP_IPV4 && LWIP_IGMP) || (LWIP_IPV6 && LWIP_IPV6_MLD)
+#if (LWIP_IPV4 && LWIP_MULTICAST_TX_OPTIONS) || (LWIP_IPV6 && LWIP_IPV6_MLD)
   if (((pcb->flags & UDP_FLAGS_MULTICAST_LOOP) != 0) && ip_addr_ismulticast(dst_ip)) {
     q->flags |= PBUF_FLAG_MCASTLOOP;
   }
-#endif /* (LWIP_IPV4 && LWIP_IGMP) || (LWIP_IPV6 && LWIP_IPV6_MLD) */
+#endif /* (LWIP_IPV4 && LWIP_MULTICAST_TX_OPTIONS) || (LWIP_IPV6 && LWIP_IPV6_MLD) */
 
   LWIP_DEBUGF(UDP_DEBUG, ("udp_send: sending datagram of length %"U16_F"\n", q->tot_len));
 
@@ -846,11 +846,11 @@ udp_sendto_if_src_chksum(struct udp_pcb *pcb, struct pbuf *p, const ip_addr_t *d
   }
 
   /* Determine TTL to use */
-#if LWIP_IGMP
+#if LWIP_MULTICAST_TX_OPTIONS
   ttl = (ip_addr_ismulticast(dst_ip) ? pcb->mcast_ttl : pcb->ttl);
-#else
+#else /* LWIP_MULTICAST_TX_OPTIONS */
   ttl = pcb->ttl;
-#endif
+#endif /* LWIP_MULTICAST_TX_OPTIONS */
 
   LWIP_DEBUGF(UDP_DEBUG, ("udp_send: UDP checksum 0x%04"X16_F"\n", udphdr->chksum));
   LWIP_DEBUGF(UDP_DEBUG, ("udp_send: ip_output_if (,,,,0x%02"X16_F",)\n", (u16_t)ip_proto));

src/include/lwip/ip4.h

@@ -128,9 +128,9 @@ err_t ip4_output_if_opt_src(struct pbuf *p, const ip4_addr_t *src, const ip4_add
        u16_t optlen);
 #endif /* IP_OPTIONS_SEND */
 
-#if LWIP_IGMP
+#if LWIP_MULTICAST_TX_OPTIONS
 void  ip4_set_default_multicast_netif(struct netif* default_multicast_netif);
-#endif /* LWIP_IGMP */
+#endif /* LWIP_MULTICAST_TX_OPTIONS */
 
 #define ip4_netif_get_local_ip(netif) (((netif) != NULL) ? &((netif)->ip_addr) : NULL)
 

src/include/lwip/opt.h

@@ -963,11 +963,11 @@
 
 /*
    ----------------------------------
-   ---------- IGMP options ----------
+   ----- Multicast/IGMP options -----
    ----------------------------------
 */
 /**
- * LWIP_IGMP==1: Turn on IGMP module. 
+ * LWIP_IGMP==1: Turn on IGMP module.
  */
 #ifndef LWIP_IGMP
 #define LWIP_IGMP                       0
@@ -977,6 +977,14 @@
 #define LWIP_IGMP                       0
 #endif
 
+/**
+ * LWIP_MULTICAST_TX_OPTIONS==1: Enable multicast TX support like the socket options
+ * IP_MULTICAST_TTL/IP_MULTICAST_IF/IP_MULTICAST_LOOP
+ */
+#ifndef LWIP_MULTICAST_TX_OPTIONS
+#define LWIP_MULTICAST_TX_OPTIONS       LWIP_IGMP
+#endif
+
 /*
    ----------------------------------
    ---------- DNS options -----------

src/include/lwip/sockets.h

@@ -253,15 +253,21 @@ struct linger {
 #endif /* LWIP_UDP && LWIP_UDPLITE*/
 
 
-#if LWIP_IGMP
+#if LWIP_MULTICAST_TX_OPTIONS
 /*
  * Options and types for UDP multicast traffic handling
  */
-#define IP_ADD_MEMBERSHIP  3
-#define IP_DROP_MEMBERSHIP 4
 #define IP_MULTICAST_TTL   5
 #define IP_MULTICAST_IF    6
 #define IP_MULTICAST_LOOP  7
+#endif /* LWIP_MULTICAST_TX_OPTIONS */
+
+#if LWIP_IGMP
+/*
+ * Options and types related to multicast membership
+ */
+#define IP_ADD_MEMBERSHIP  3
+#define IP_DROP_MEMBERSHIP 4
 
 typedef struct ip_mreq {
     struct in_addr imr_multiaddr; /* IP multicast address of group */

src/include/lwip/udp.h

@@ -100,12 +100,12 @@ struct udp_pcb {
   /** ports are in host byte order */
   u16_t local_port, remote_port;
 
-#if LWIP_IGMP
+#if LWIP_MULTICAST_TX_OPTIONS
   /** outgoing network interface for multicast packets */
   ip4_addr_t multicast_ip;
   /** TTL for outgoing multicast packets */
   u8_t mcast_ttl;
-#endif /* LWIP_IGMP */
+#endif /* LWIP_MULTICAST_TX_OPTIONS */
 
 #if LWIP_UDPLITE
   /** used for UDP_LITE only */
@@ -168,12 +168,12 @@ void             udp_init       (void);
 struct udp_pcb * udp_new_ip6(void);
 #endif /* LWIP_IPV6 */
 
-#if LWIP_IGMP
+#if LWIP_MULTICAST_TX_OPTIONS
 #define udp_set_multicast_netif_addr(pcb, ip4addr) do { (pcb)->multicast_ip = *(ip4addr); } while(0)
 #define udp_get_multicast_netif_addr(pcb)          (&(pcb)->multicast_ip)
 #define udp_set_multicast_ttl(pcb, value)      do { (pcb)->mcast_ttl = value; } while(0)
 #define udp_get_multicast_ttl(pcb)                 ((pcb)->mcast_ttl)
-#endif /* LWIP_IGMP */
+#endif /* LWIP_MULTICAST_TX_OPTIONS */
 
 #if UDP_DEBUG
 void udp_debug_print(struct udp_hdr *udphdr);