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>

diff --git a/include/net.h b/include/net.h
index d5d37b6506b05989f37d31cb08676edbab47fda1..d7ff0687ccacc49812fc58b7299e219c1cf26785 100644 (file)
--- a/include/net.h
+++ b/include/net.h
@@ -48,6 +48,19 @@ typedef void rxhand_f(uchar *pkt, unsigned dport,
                      IPaddr_t sip, unsigned sport,
                      unsigned len);
 
+/**
+ * An incoming ICMP packet handler.
+ * @param type ICMP type
+ * @param code ICMP code
+ * @param dport        destination UDP port
+ * @param sip  source IP address
+ * @param sport        source UDP port
+ * @param pkt  pointer to the ICMP packet data
+ * @param len  packet length
+ */
+typedef void rxhand_icmp_f(unsigned type, unsigned code, unsigned dport,
+               IPaddr_t sip, unsigned sport, uchar *pkt, unsigned len);
+
 /*
  *     A timeout handler.  Called after time interval has expired.
  */
@@ -244,6 +257,7 @@ typedef struct
  * ICMP stuff (just enough to handle (host) redirect messages)
  */
 #define ICMP_ECHO_REPLY                0       /* Echo reply                   */
+#define ICMP_NOT_REACH         3       /* Detination unreachable       */
 #define ICMP_REDIRECT          5       /* Redirect (change route)      */
 #define ICMP_ECHO_REQUEST      8       /* Echo request                 */
 
@@ -251,6 +265,9 @@ typedef struct
 #define ICMP_REDIR_NET         0       /* Redirect Net                 */
 #define ICMP_REDIR_HOST                1       /* Redirect Host                */
 
+/* Codes for NOT_REACH */
+#define ICMP_NOT_REACH_PORT    3       /* Port unreachable             */
+
 typedef struct icmphdr {
        uchar           type;
        uchar           code;
@@ -265,6 +282,7 @@ typedef struct icmphdr {
                        ushort  __unused;
                        ushort  mtu;
                } frag;
+               uchar data[0];
        } un;
 } ICMP_t;
 
@@ -397,6 +415,7 @@ extern uint NetCksum(uchar *, int);         /* Calculate the checksum       */
 
 /* Set callbacks */
 extern void    NetSetHandler(rxhand_f *);      /* Set RX packet handler        */
+extern void net_set_icmp_handler(rxhand_icmp_f *f); /* Set ICMP RX handler */
 extern void    NetSetTimeout(ulong, thand_f *);/* Set timeout handler          */
 
 /* Transmit "NetTxPacket" */

diff --git a/net/net.c b/net/net.c
index 266b9538d8c916b67f660becf356fdd8742de5b9..f6afb6439624133e8a1d5125849d22ce0c0a5e16 100644 (file)
--- 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);