Changeset 4c55a64 in mainline for uspace/srv/net/tl/tcp/conn.c

Timestamp:

2011-09-19T21:01:16Z (13 years ago)

Author:

Jiri Svoboda <jiri@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

0093ab6

Parents:

c5808b41

Message:

Implement some ACK processing and window-size update handling.

File:

• uspace/srv/net/tl/tcp/conn.c (modified) (15 diffs)

uspace/srv/net/tl/tcp/conn.c

@@ -152 +152 @@
         conn->irs = seg->seq;
 
+
         log_msg(LVL_DEBUG, "rcv_nxt=%u", conn->rcv_nxt);
 
@@ -161 +162 @@
         conn->snd_nxt = conn->iss;
         conn->snd_una = conn->iss;
+
+        /*
+         * Surprisingly the spec does not deal with initial window setting.
+         * Set SND.WND = SEG.WND and set SND.WL1 so that next segment
+         * will always be accepted as new window setting.
+         */
+        conn->snd_wnd = seg->wnd;
+        conn->snd_wl1 = seg->seq;
+        conn->snd_wl2 = seg->seq;
 
         conn->cstate = st_syn_received;
@@ -201 +211 @@
         if ((seg->ctrl & CTL_ACK) != 0) {
                 conn->snd_una = seg->ack;
-                /* XXX process retransmission queue */
+                tcp_tqueue_remove_acked(conn);
         }
 
@@ -240 +250 @@
 static cproc_t tcp_conn_seg_proc_rst(tcp_conn_t *conn, tcp_segment_t *seg)
 {
+        /* TODO */
         return cp_continue;
 }
@@ -245 +256 @@
 static cproc_t tcp_conn_seg_proc_sp(tcp_conn_t *conn, tcp_segment_t *seg)
 {
+        /* TODO */
         return cp_continue;
 }
@@ -250 +262 @@
 static cproc_t tcp_conn_seg_proc_syn(tcp_conn_t *conn, tcp_segment_t *seg)
 {
+        /* TODO */
         return cp_continue;
 }
@@ -259 +272 @@
                 log_msg(LVL_WARN, "Segment ACK not acceptable, sending RST.");
                 tcp_reply_rst(&conn->ident, seg);
+                tcp_segment_delete(seg);
+                return cp_done;
         }
 
@@ -273 +288 @@
 static cproc_t tcp_conn_seg_proc_ack_est(tcp_conn_t *conn, tcp_segment_t *seg)
 {
+        if (!seq_no_ack_acceptable(conn, seg->ack)) {
+                if (!seq_no_ack_duplicate(conn, seg->ack)) {
+                        /* Not acceptable, not duplicate. Send ACK and drop. */
+                        tcp_tqueue_ctrl_seg(conn, CTL_ACK);
+                        tcp_segment_delete(seg);
+                        return cp_done;
+                }
+        } else {
+                /* Update SND.UNA */
+                conn->snd_una = seg->ack;
+
+                /* Prune acked segments from retransmission queue */
+                tcp_tqueue_remove_acked(conn);
+        }
+
+        if (seq_no_new_wnd_update(conn, seg)) {
+                conn->snd_wnd = seg->wnd;
+                conn->snd_wl1 = seg->seq;
+                conn->snd_wl2 = seg->ack;
+        }
+
         return cp_continue;
 }
@@ -278 +314 @@
 static cproc_t tcp_conn_seg_proc_ack_fw1(tcp_conn_t *conn, tcp_segment_t *seg)
 {
+        if (tcp_conn_seg_proc_ack_est(conn, seg) == cp_done)
+                return cp_done;
+
+        /* TODO */
         return cp_continue;
 }
@@ -283 +323 @@
 static cproc_t tcp_conn_seg_proc_ack_fw2(tcp_conn_t *conn, tcp_segment_t *seg)
 {
+        if (tcp_conn_seg_proc_ack_est(conn, seg) == cp_done)
+                return cp_done;
+
+        /* TODO */
         return cp_continue;
 }
@@ -288 +332 @@
 static cproc_t tcp_conn_seg_proc_ack_cw(tcp_conn_t *conn, tcp_segment_t *seg)
 {
-        return cp_continue;
+        /* The same processing as in Established state */
+        return tcp_conn_seg_proc_ack_est(conn, seg);
 }
 
 static cproc_t tcp_conn_seg_proc_ack_cls(tcp_conn_t *conn, tcp_segment_t *seg)
 {
+        if (tcp_conn_seg_proc_ack_est(conn, seg) == cp_done)
+                return cp_done;
+
+        /* TODO */
         return cp_continue;
 }
@@ -298 +347 @@
 static cproc_t tcp_conn_seg_proc_ack_la(tcp_conn_t *conn, tcp_segment_t *seg)
 {
+        if (tcp_conn_seg_proc_ack_est(conn, seg) == cp_done)
+                return cp_done;
+
+        /* TODO */
         return cp_continue;
 }
@@ -303 +356 @@
 static cproc_t tcp_conn_seg_proc_ack_tw(tcp_conn_t *conn, tcp_segment_t *seg)
 {
+        /* Nothing to do */
         return cp_continue;
 }
@@ -312 +366 @@
         if ((seg->ctrl & CTL_ACK) == 0) {
                 log_msg(LVL_WARN, "Segment has no ACK. Dropping.");
-                /* XXX Free segment */
+                tcp_segment_delete(seg);
                 return cp_done;
         }
@@ -349 +403 @@
 static cproc_t tcp_conn_seg_proc_text(tcp_conn_t *conn, tcp_segment_t *seg)
 {
+        switch (conn->cstate) {
+        case st_established:
+        case st_fin_wait_1:
+        case st_fin_wait_2:
+                /* OK */
+                break;
+        case st_close_wait:
+        case st_closing:
+        case st_last_ack:
+        case st_time_wait:
+                /* Invalid since FIN has been received. Ignore text. */
+                return cp_continue;
+        case st_listen:
+        case st_syn_sent:
+        case st_syn_received:
+        case st_closed:
+                assert(false);
+        }
+
+        /* TODO Process segment text */
         return cp_continue;
 }