Diff: lwip/core/udp.c

Revision:

1:3a7c15057192

Parent:

0:b802fc31f1db

diff -r b802fc31f1db -r 3a7c15057192 lwip/core/udp.c
--- a/lwip/core/udp.c	Fri Jul 09 15:37:23 2010 +0000
+++ b/lwip/core/udp.c	Fri Aug 06 10:23:41 2010 +0000
@@ -113,7 +113,7 @@
   udphdr = (struct udp_hdr *)p->payload;
 
   /* is broadcast packet ? */
-  broadcast = ip_addr_isbroadcast(&(iphdr->dest), inp);
+  broadcast = ip_addr_isbroadcast(&current_iphdr_dest, inp);
 
   LWIP_DEBUGF(UDP_DEBUG, ("udp_input: received datagram of length %"U16_F"\n", p->tot_len));
 
@@ -144,7 +144,7 @@
            (- broadcast or directed to us) -> DHCP is link-layer-addressed, local ip is always ANY!
            - inp->dhcp->pcb->remote == ANY or iphdr->src */
         if ((ip_addr_isany(&inp->dhcp->pcb->remote_ip) ||
-           ip_addr_cmp(&(inp->dhcp->pcb->remote_ip), &(iphdr->src)))) {
+           ip_addr_cmp(&(inp->dhcp->pcb->remote_ip), &current_iphdr_src))) {
           pcb = inp->dhcp->pcb;
         }
       }
@@ -173,9 +173,9 @@
       /* compare PCB local addr+port to UDP destination addr+port */
       if ((pcb->local_port == dest) &&
           ((!broadcast && ip_addr_isany(&pcb->local_ip)) ||
-           ip_addr_cmp(&(pcb->local_ip), &(iphdr->dest)) ||
+           ip_addr_cmp(&(pcb->local_ip), &current_iphdr_dest) ||
 #if LWIP_IGMP
-           ip_addr_ismulticast(&(iphdr->dest)) ||
+           ip_addr_ismulticast(&current_iphdr_dest) ||
 #endif /* LWIP_IGMP */
 #if IP_SOF_BROADCAST_RECV
            (broadcast && (pcb->so_options & SOF_BROADCAST)))) {
@@ -193,7 +193,7 @@
       if ((local_match != 0) &&
           (pcb->remote_port == src) &&
           (ip_addr_isany(&pcb->remote_ip) ||
-           ip_addr_cmp(&(pcb->remote_ip), &(iphdr->src)))) {
+           ip_addr_cmp(&(pcb->remote_ip), &current_iphdr_src))) {
         /* the first fully matching PCB */
         if (prev != NULL) {
           /* move the pcb to the front of udp_pcbs so that is
@@ -215,7 +215,7 @@
   }
 
   /* Check checksum if this is a match or if it was directed at us. */
-  if (pcb != NULL || ip_addr_cmp(&inp->ip_addr, &iphdr->dest)) {
+  if (pcb != NULL || ip_addr_cmp(&inp->ip_addr, &current_iphdr_dest)) {
     LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE, ("udp_input: calculating checksum\n"));
 #if LWIP_UDPLITE
     if (IPH_PROTO(iphdr) == IP_PROTO_UDPLITE) {
@@ -237,7 +237,7 @@
           goto end;
         }
       }
-      if (inet_chksum_pseudo_partial(p, &iphdr->src, &iphdr->dest,
+      if (inet_chksum_pseudo_partial(p, &current_iphdr_src, &current_iphdr_dest,
                              IP_PROTO_UDPLITE, p->tot_len, chklen) != 0) {
        LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
                    ("udp_input: UDP Lite datagram discarded due to failing checksum\n"));
@@ -253,7 +253,7 @@
     {
 #if CHECKSUM_CHECK_UDP
       if (udphdr->chksum != 0) {
-        if (inet_chksum_pseudo(p, &iphdr->src, &iphdr->dest,
+        if (inet_chksum_pseudo(p, ip_current_src_addr(), ip_current_dest_addr(),
                                IP_PROTO_UDP, p->tot_len) != 0) {
           LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
                       ("udp_input: UDP datagram discarded due to failing checksum\n"));
@@ -276,10 +276,58 @@
     }
     if (pcb != NULL) {
       snmp_inc_udpindatagrams();
+#if SO_REUSE && SO_REUSE_RXTOALL
+      if ((broadcast || ip_addr_ismulticast(&current_iphdr_dest)) &&
+          ((pcb->so_options & SOF_REUSEADDR) != 0)) {
+        /* pass broadcast- or multicast packets to all multicast pcbs
+           if SOF_REUSEADDR is set on the first match */
+        struct udp_pcb *mpcb;
+        u8_t p_header_changed = 0;
+        for (mpcb = udp_pcbs; mpcb != NULL; mpcb = mpcb->next) {
+          if (mpcb != pcb) {
+            /* compare PCB local addr+port to UDP destination addr+port */
+            if ((mpcb->local_port == dest) &&
+                ((!broadcast && ip_addr_isany(&mpcb->local_ip)) ||
+                 ip_addr_cmp(&(mpcb->local_ip), &current_iphdr_dest) ||
+#if LWIP_IGMP
+                 ip_addr_ismulticast(&current_iphdr_dest) ||
+#endif /* LWIP_IGMP */
+#if IP_SOF_BROADCAST_RECV
+                 (broadcast && (mpcb->so_options & SOF_BROADCAST)))) {
+#else  /* IP_SOF_BROADCAST_RECV */
+                 (broadcast))) {
+#endif /* IP_SOF_BROADCAST_RECV */
+              /* pass a copy of the packet to all local matches */
+              if (mpcb->recv != NULL) {
+                struct pbuf *q;
+                /* for that, move payload to IP header again */
+                if (p_header_changed == 0) {
+                  pbuf_header(p, (s16_t)((IPH_HL(iphdr) * 4) + UDP_HLEN));
+                  p_header_changed = 1;
+                }
+                q = pbuf_alloc(PBUF_RAW, p->tot_len, PBUF_RAM);
+                if (q != NULL) {
+                  err_t err = pbuf_copy(q, p);
+                  if (err == ERR_OK) {
+                    /* move payload to UDP data */
+                    pbuf_header(q, -(s16_t)((IPH_HL(iphdr) * 4) + UDP_HLEN));
+                    mpcb->recv(mpcb->recv_arg, mpcb, q, ip_current_src_addr(), src);
+                  }
+                }
+              }
+            }
+          }
+        }
+        if (p_header_changed) {
+          /* and move payload to UDP data again */
+          pbuf_header(p, -(s16_t)((IPH_HL(iphdr) * 4) + UDP_HLEN));
+        }
+      }
+#endif /* SO_REUSE && SO_REUSE_RXTOALL */
       /* callback */
       if (pcb->recv != NULL) {
         /* now the recv function is responsible for freeing p */
-        pcb->recv(pcb->recv_arg, pcb, p, &iphdr->src, src);
+        pcb->recv(pcb->recv_arg, pcb, p, ip_current_src_addr(), src);
       } else {
         /* no recv function registered? then we have to free the pbuf! */
         pbuf_free(p);
@@ -292,7 +340,7 @@
       /* No match was found, send ICMP destination port unreachable unless
          destination address was broadcast/multicast. */
       if (!broadcast &&
-          !ip_addr_ismulticast(&iphdr->dest)) {
+          !ip_addr_ismulticast(&current_iphdr_dest)) {
         /* move payload pointer back to ip header */
         pbuf_header(p, (IPH_HL(iphdr) * 4) + UDP_HLEN);
         LWIP_ASSERT("p->payload == iphdr", (p->payload == iphdr));
@@ -336,6 +384,19 @@
   return udp_sendto(pcb, p, &pcb->remote_ip, pcb->remote_port);
 }
 
+#if LWIP_CHECKSUM_ON_COPY
+/** Same as udp_send() but with checksum
+ */
+err_t
+udp_send_chksum(struct udp_pcb *pcb, struct pbuf *p,
+                u8_t have_chksum, u16_t chksum)
+{
+  /* send to the packet using remote ip and port stored in the pcb */
+  return udp_sendto_chksum(pcb, p, &pcb->remote_ip, pcb->remote_port,
+    have_chksum, chksum);
+}
+#endif /* LWIP_CHECKSUM_ON_COPY */
+
 /**
  * Send data to a specified address using UDP.
  *
@@ -357,6 +418,16 @@
 udp_sendto(struct udp_pcb *pcb, struct pbuf *p,
   ip_addr_t *dst_ip, u16_t dst_port)
 {
+#if LWIP_CHECKSUM_ON_COPY
+  return udp_sendto_chksum(pcb, p, dst_ip, dst_port, 0, 0);
+}
+
+/** Same as udp_sendto(), but with checksum */
+err_t
+udp_sendto_chksum(struct udp_pcb *pcb, struct pbuf *p, ip_addr_t *dst_ip,
+                  u16_t dst_port, u8_t have_chksum, u16_t chksum)
+{
+#endif /* LWIP_CHECKSUM_ON_COPY */
   struct netif *netif;
 
   LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE, ("udp_send\n"));
@@ -375,7 +446,11 @@
     UDP_STATS_INC(udp.rterr);
     return ERR_RTE;
   }
+#if LWIP_CHECKSUM_ON_COPY
+  return udp_sendto_if_chksum(pcb, p, dst_ip, dst_port, netif, have_chksum, chksum);
+#else /* LWIP_CHECKSUM_ON_COPY */
   return udp_sendto_if(pcb, p, dst_ip, dst_port, netif);
+#endif /* LWIP_CHECKSUM_ON_COPY */
 }
 
 /**
@@ -401,6 +476,17 @@
 udp_sendto_if(struct udp_pcb *pcb, struct pbuf *p,
   ip_addr_t *dst_ip, u16_t dst_port, struct netif *netif)
 {
+#if LWIP_CHECKSUM_ON_COPY
+  return udp_sendto_if_chksum(pcb, p, dst_ip, dst_port, netif, 0, 0);
+}
+
+/** Same as udp_sendto_if(), but with checksum */
+err_t
+udp_sendto_if_chksum(struct udp_pcb *pcb, struct pbuf *p, ip_addr_t *dst_ip,
+                     u16_t dst_port, struct netif *netif, u8_t have_chksum,
+                     u16_t chksum)
+{
+#endif /* LWIP_CHECKSUM_ON_COPY */
   struct udp_hdr *udphdr;
   ip_addr_t *src_ip;
   err_t err;
@@ -454,6 +540,14 @@
   /* in UDP, 0 checksum means 'no checksum' */
   udphdr->chksum = 0x0000; 
 
+  /* Multicast Loop? */
+#if LWIP_IGMP
+  if (ip_addr_ismulticast(dst_ip) && ((pcb->flags & UDP_FLAGS_MULTICAST_LOOP) != 0)) {
+    q->flags |= PBUF_FLAG_MCASTLOOP;
+  }
+#endif /* LWIP_IGMP */
+
+
   /* PCB local address is IP_ANY_ADDR? */
   if (ip_addr_isany(&pcb->local_ip)) {
     /* use outgoing network interface IP address as source address */
@@ -501,7 +595,18 @@
     /* calculate checksum */
 #if CHECKSUM_GEN_UDP
     udphdr->chksum = inet_chksum_pseudo_partial(q, src_ip, dst_ip,
-                                        IP_PROTO_UDPLITE, q->tot_len, chklen);
+      IP_PROTO_UDPLITE, q->tot_len,
+#if !LWIP_CHECKSUM_ON_COPY
+      chklen);
+#else /* !LWIP_CHECKSUM_ON_COPY */
+      (have_chksum ? UDP_HLEN : chklen));
+    if (have_chksum) {
+      u32_t acc;
+      acc = udphdr->chksum + (u16_t)~(chksum);
+      udphdr->chksum = FOLD_U32T(acc);
+    }
+#endif /* !LWIP_CHECKSUM_ON_COPY */
+
     /* chksum zero must become 0xffff, as zero means 'no checksum' */
     if (udphdr->chksum == 0x0000) {
       udphdr->chksum = 0xffff;
@@ -524,11 +629,25 @@
     /* calculate checksum */
 #if CHECKSUM_GEN_UDP
     if ((pcb->flags & UDP_FLAGS_NOCHKSUM) == 0) {
-      udphdr->chksum = inet_chksum_pseudo(q, src_ip, dst_ip, IP_PROTO_UDP, q->tot_len);
+      u16_t udpchksum;
+#if LWIP_CHECKSUM_ON_COPY
+      if (have_chksum) {
+        u32_t acc;
+        udpchksum = inet_chksum_pseudo_partial(q, src_ip, dst_ip, IP_PROTO_UDP,
+          q->tot_len, UDP_HLEN);
+        acc = udpchksum + (u16_t)~(chksum);
+        udpchksum = FOLD_U32T(acc);
+      } else
+#endif /* LWIP_CHECKSUM_ON_COPY */
+      {
+        udpchksum = inet_chksum_pseudo(q, src_ip, dst_ip, IP_PROTO_UDP, q->tot_len);
+      }
+
       /* chksum zero must become 0xffff, as zero means 'no checksum' */
-      if (udphdr->chksum == 0x0000) {
-        udphdr->chksum = 0xffff;
+      if (udpchksum == 0x0000) {
+        udpchksum = 0xffff;
       }
+      udphdr->chksum = udpchksum;
     }
 #endif /* CHECKSUM_GEN_UDP */
     LWIP_DEBUGF(UDP_DEBUG, ("udp_send: UDP checksum 0x%04"X16_F"\n", udphdr->chksum));
@@ -597,13 +716,16 @@
       rebind = 1;
     }
 
-    /* this code does not allow upper layer to share a UDP port for
-       listening to broadcast or multicast traffic (See SO_REUSEADDR and
-       SO_REUSEPORT under *BSD). TODO: See where it fits instead, OR
-       combine with implementation of UDP PCB flags. Leon Woestenberg. */
-#ifdef LWIP_UDP_TODO
-    /* port matches that of PCB in list? */
+    /* By default, we don't allow to bind to a port that any other udp
+       PCB is alread bound to, unless *all* PCBs with that port have tha
+       REUSEADDR flag set. */
+#if SO_REUSE
+    else if (((pcb->so_options & SOF_REUSEADDR) == 0) &&
+             ((ipcb->so_options & SOF_REUSEADDR) == 0)) {
+#else /* SO_REUSE */
+    /* port matches that of PCB in list and REUSEADDR not set -> reject */
     else {
+#endif /* SO_REUSE */
       if ((ipcb->local_port == port) &&
           /* IP address matches, or one is IP_ADDR_ANY? */
           (ip_addr_isany(&(ipcb->local_ip)) ||
@@ -615,7 +737,6 @@
         return ERR_USE;
       }
     }
-#endif
   }
 
   ip_addr_set(&pcb->local_ip, ipaddr);