net: tftpput: Add support for receiving ICMP packets

ICMP packets can tell you when there is no server at the other end. It
is useful for tftp to figure this out, so that a quick error can be
displayed, rather than pointlessly retrying.

This adds an ICMP packet handler to the net interface.

Signed-off-by: Simon Glass <sjg@chromium.org>

1 files changed, 24 insertions, 3 deletions

diff --git a/net/net.c b/net/net.c
index 266b953..f6afb64 100644
--- a/net/net.c
+++ b/net/net.c
@@ -215,6 +215,7 @@ volatile uchar *NetRxPackets[PKTBUFSRX];
 
 /* Current RX packet handler */
 static rxhand_f *packetHandler;
+static rxhand_icmp_f *packet_icmp_handler;	/* Current ICMP rx handler */
 /* Current timeout handler */
 static thand_f *timeHandler;
 /* Time base value */
@@ -344,6 +345,7 @@ int
 NetLoop(proto_t protocol)
 {
 	bd_t *bd = gd->bd;
+	int ret = -1;
 
 	NetRestarted = 0;
 	NetDevExists = 0;
@@ -512,7 +514,7 @@ restart:
 		if (ctrlc()) {
 			eth_halt();
 			puts("\nAbort\n");
-			return -1;
+			goto done;
 		}
 
 		ArpTimeoutCheck();
@@ -564,12 +566,19 @@ restart:
 				setenv("fileaddr", buf);
 			}
 			eth_halt();
-			return NetBootFileXferSize;
+			ret = NetBootFileXferSize;
+			goto done;
 
 		case NETLOOP_FAIL:
-			return -1;
+			goto done;
 		}
 	}
+
+done:
+	/* Clear out the handlers */
+	NetSetHandler(NULL);
+	net_set_icmp_handler(NULL);
+	return ret;
 }
 
 /**********************************************************************/
@@ -643,6 +652,10 @@ NetSetHandler(rxhand_f *f)
 	packetHandler = f;
 }
 
+void net_set_icmp_handler(rxhand_icmp_f *f)
+{
+	packet_icmp_handler = f;
+}
 
 void
 NetSetTimeout(ulong iv, thand_f *f)
@@ -1383,6 +1396,10 @@ static void receive_icmp(IP_t *ip, int len, IPaddr_t src_ip, Ethernet_t *et)
 		break;
 #endif
 	default:
+		if (packet_icmp_handler)
+			packet_icmp_handler(icmph->type, icmph->code,
+				ntohs(ip->udp_dst), src_ip, ntohs(ip->udp_src),
+				icmph->un.data, ntohs(ip->udp_len));
 		break;
 	}
 }
@@ -1671,6 +1688,10 @@ NetReceive(volatile uchar *inpkt, int len)
 		 * subnet. So this is probably a warning that your
 		 * configuration might be wrong. But I'm not really
 		 * sure if there aren't any other situations.
+		 *
+		 * Simon Glass <sjg@chromium.org>: We get an ICMP when
+		 * we send a tftp packet to a dead connection, or when
+		 * there is no server at the other end.
 		 */
 		if (ip->ip_p == IPPROTO_ICMP) {
 			receive_icmp(ip, len, src_ip, et);