Fix memory and resource leaks.

[utcp] / utcp.c

diff --git a/utcp.c b/utcp.c
index 454a497428dd0e698db2bdeae92189fda41eb0fb..1fae32cd2eaf44430f93311a0787034c58e2861d 100644 (file)
--- a/utcp.c
+++ b/utcp.c
@@ -127,6 +127,7 @@ static void free_connection(struct utcp_connection *c) {
        memmove(cp + i, cp + i + 1, (utcp->nconnections - i - 1) * sizeof *cp);
        utcp->nconnections--;
 
+       free(c->sndbuf);
        free(c);
 }
 
@@ -206,8 +207,9 @@ struct utcp_connection *utcp_connect(struct utcp *utcp, uint16_t dst, utcp_recv_
        hdr.dst = c->dst;
        hdr.seq = c->snd.iss;
        hdr.ack = 0;
-       hdr.ctl = SYN;
        hdr.wnd = c->rcv.wnd;
+       hdr.ctl = SYN;
+       hdr.aux = 0;
 
        set_state(c, SYN_SENT);
 
@@ -233,10 +235,14 @@ void utcp_accept(struct utcp_connection *c, utcp_recv_t recv, void *priv) {
 }
 
 static void ack(struct utcp_connection *c, bool sendatleastone) {
-       uint32_t left = seqdiff(c->snd.last, c->snd.nxt);
+       int32_t left = seqdiff(c->snd.last, c->snd.nxt);
        int32_t cwndleft = c->snd.cwnd - seqdiff(c->snd.nxt, c->snd.una);
        char *data = c->sndbuf + seqdiff(c->snd.nxt, c->snd.una);
 
+       fprintf(stderr, "ack, left=%d, cwndleft=%d, sendatleastone=%d\n", left, cwndleft, sendatleastone);
+       if(left < 0)
+               abort();
+
        if(cwndleft <= 0)
                cwndleft = 0;
 
@@ -256,6 +262,7 @@ static void ack(struct utcp_connection *c, bool sendatleastone) {
        pkt.hdr.ack = c->rcv.nxt;
        pkt.hdr.wnd = c->snd.wnd;
        pkt.hdr.ctl = ACK;
+       pkt.hdr.aux = 0;
 
        do {
                uint32_t seglen = left > c->utcp->mtu ? c->utcp->mtu : left;
@@ -267,6 +274,18 @@ static void ack(struct utcp_connection *c, bool sendatleastone) {
                data += seglen;
                left -= seglen;
 
+               if(c->state != ESTABLISHED && !left && seglen) {
+                       switch(c->state) {
+                       case FIN_WAIT_1:
+                       case CLOSING:
+                               seglen--;
+                               pkt.hdr.ctl |= FIN;
+                               break;
+                       default:
+                               break;
+                       }
+               }
+
                print_packet(c->utcp, "send", &pkt, sizeof pkt.hdr + seglen);
                c->utcp->send(c->utcp, &pkt, sizeof pkt.hdr + seglen);
        } while(left);
@@ -324,6 +343,12 @@ ssize_t utcp_send(struct utcp_connection *c, const void *data, size_t len) {
                        newbufsize = c->maxsndbufsize;
                else
                        newbufsize = c->sndbufsize * 2;
+               if(bufused + len > newbufsize) {
+                       if(bufused + len > c->maxsndbufsize)
+                               newbufsize = c->maxsndbufsize;
+                       else
+                               newbufsize = bufused + len;
+               }
                char *newbuf = realloc(c->sndbuf, newbufsize);
                if(newbuf) {
                        c->sndbuf = newbuf;
@@ -584,6 +609,24 @@ int utcp_recv(struct utcp *utcp, const void *data, size_t len) {
                c->snd.cwnd += utcp->mtu;
                if(c->snd.cwnd > c->maxsndbufsize)
                        c->snd.cwnd = c->maxsndbufsize;
+               debug("%p increasing cwnd to %u\n", utcp, c->snd.cwnd);
+
+               // Check if we have sent a FIN that is now ACKed.
+               switch(c->state) {
+               case FIN_WAIT_1:
+                       if(c->snd.una == c->snd.last)
+                               set_state(c, FIN_WAIT_2);
+                       break;
+               case CLOSING:
+                       if(c->snd.una == c->snd.last) {
+                               gettimeofday(&c->conn_timeout, NULL);
+                               c->conn_timeout.tv_sec += 60;
+                               set_state(c, TIME_WAIT);
+                       }
+                       break;
+               default:
+                       break;
+               }
        } else {
                if(!len) {
                        c->dupack++;
@@ -701,6 +744,8 @@ int utcp_recv(struct utcp *utcp, const void *data, size_t len) {
                        set_state(c, CLOSING);
                        break;
                case FIN_WAIT_2:
+                       gettimeofday(&c->conn_timeout, NULL);
+                       c->conn_timeout.tv_sec += 60;
                        set_state(c, TIME_WAIT);
                        break;
                case CLOSE_WAIT:
@@ -715,6 +760,7 @@ int utcp_recv(struct utcp *utcp, const void *data, size_t len) {
 
                // FIN counts as one sequence number
                c->rcv.nxt++;
+               len++;
 
                // Inform the application that the peer closed the connection.
                if(c->recv) {
@@ -790,21 +836,9 @@ int utcp_shutdown(struct utcp_connection *c, int dir) {
                return 0;
        }
 
-       // Send FIN
-
-       struct hdr hdr;
-
-       hdr.src = c->src;
-       hdr.dst = c->dst;
-       hdr.seq = c->snd.nxt;
-       hdr.ack = c->rcv.nxt;
-       hdr.wnd = c->snd.wnd;
-       hdr.ctl = FIN | ACK;
+       c->snd.last++;
 
-       c->snd.nxt += 1;
-
-       print_packet(c->utcp, "send", &hdr, sizeof hdr);
-       c->utcp->send(c->utcp, &hdr, sizeof hdr);
+       ack(c, false);
        return 0;
 }
 
@@ -1007,8 +1041,13 @@ struct utcp *utcp_init(utcp_accept_t accept, utcp_pre_accept_t pre_accept, utcp_
 void utcp_exit(struct utcp *utcp) {
        if(!utcp)
                return;
-       for(int i = 0; i < utcp->nconnections; i++)
-               free_connection(utcp->connections[i]);
+       for(int i = 0; i < utcp->nconnections; i++) {
+               if(!utcp->connections[i]->reapable)
+                       debug("Warning, freeing unclosed connection %p\n", utcp->connections[i]);
+               free(utcp->connections[i]->sndbuf);
+               free(utcp->connections[i]);
+       }
+       free(utcp->connections);
        free(utcp);
 }