Verify checksums on the RX datapath.

[people/xl0/gpxe.git] / src / net / tcp.c

diff --git a/src/net/tcp.c b/src/net/tcp.c
index cd625c3..d9d427c 100644 (file)
--- a/src/net/tcp.c
+++ b/src/net/tcp.c
@@ -309,7 +309,7 @@ static int tcp_senddata_conn ( struct tcp_connection *conn, int force_send ) {
        DBGC ( conn, "\n" );
 
        /* Transmit packet */
-       return tcpip_tx ( pkb, &tcp_protocol, &conn->peer );
+       return tcpip_tx ( pkb, &tcp_protocol, &conn->peer, &tcphdr->csum );
 }
 
 /**
@@ -591,14 +591,19 @@ static int tcp_rx_fin ( struct tcp_connection *conn, uint32_t seq ) {
  * Process received packet
  *
  * @v pkb              Packet buffer
- * @v partial          Partial checksum
- */
+ * @v st_src           Partially-filled source address
+ * @v st_dest          Partially-filled destination address
+ * @v pshdr_csum       Pseudo-header checksum
+ * @ret rc             Return status code
+  */
 static int tcp_rx ( struct pk_buff *pkb,
                    struct sockaddr_tcpip *st_src __unused,
-                   struct sockaddr_tcpip *st_dest __unused ) {
+                   struct sockaddr_tcpip *st_dest __unused,
+                   uint16_t pshdr_csum ) {
        struct tcp_header *tcphdr;
        struct tcp_connection *conn;
        unsigned int hlen;
+       uint16_t csum;
        uint32_t start_seq;
        uint32_t seq;
        uint32_t ack;
@@ -608,7 +613,7 @@ static int tcp_rx ( struct pk_buff *pkb,
        size_t len;
        int rc = 0;
 
-       /* Sanity check packet and strip TCP header */
+       /* Sanity check packet */
        if ( pkb_len ( pkb ) < sizeof ( *tcphdr ) ) {
                DBG ( "TCP packet too short at %d bytes (min %d bytes)\n",
                      pkb_len ( pkb ), sizeof ( *tcphdr ) );
@@ -629,9 +634,12 @@ static int tcp_rx ( struct pk_buff *pkb,
                rc = -EINVAL;
                goto err;
        }
-
-       /* TODO: Verify checksum */
-#warning "Verify checksum"
+       csum = tcpip_continue_chksum ( pshdr_csum, pkb->data, pkb_len ( pkb ));
+       if ( csum != 0 ) {
+               DBG ( "TCP checksum incorrect (is %04x including checksum "
+                     "field, should be 0000)\n", csum );
+               goto err;
+       }
        
        /* Parse parameters from header and strip header */
        conn = tcp_demux ( tcphdr->dest );
@@ -845,5 +853,4 @@ struct tcpip_protocol tcp_protocol __tcpip_protocol = {
        .name = "TCP",
        .rx = tcp_rx,
        .tcpip_proto = IP_TCP,
-       .csum_offset = 16,
 };