Hiroshi Oota points out that PuTTY's agent forwarding sockets can get

[u/mdw/putty] / ssh.c

diff --git a/ssh.c b/ssh.c
index fa400c3..e09ce73 100644 (file)
--- a/ssh.c
+++ b/ssh.c
@@ -589,14 +589,6 @@ struct outstanding_channel_request {
 };
 
 /*
- * little structure to keep track of outstanding WINDOW_ADJUSTs
- */
-struct winadj {
-    struct winadj *next;
-    unsigned size;
-};
-
-/*
  * 2-3-4 tree storing channels.
  */
 struct ssh_channel {
@@ -674,6 +666,7 @@ struct ssh_channel {
            unsigned char *message;
            unsigned char msglen[4];
            unsigned lensofar, totallen;
+            int outstanding_requests;
        } a;
        struct ssh_x11_channel {
            Socket s;
@@ -3209,6 +3202,7 @@ static void ssh_agentf_callback(void *cv, void *reply, int replylen)
     Ssh ssh = c->ssh;
     void *sentreply = reply;
 
+    c->u.a.outstanding_requests--;
     if (!sentreply) {
        /* Fake SSH_AGENT_FAILURE. */
        sentreply = "\0\0\0\1\5";
@@ -3228,6 +3222,12 @@ static void ssh_agentf_callback(void *cv, void *reply, int replylen)
     }
     if (reply)
        sfree(reply);
+    /*
+     * If we've already seen an incoming EOF but haven't sent an
+     * outgoing one, this may be the moment to send it.
+     */
+    if (c->u.a.outstanding_requests == 0 && (c->closes & CLOSES_RCVD_EOF))
+        sshfwd_write_eof(c);
 }
 
 /*
@@ -4835,6 +4835,7 @@ static void ssh1_smsg_agent_open(Ssh ssh, struct Packet *pktin)
        c->type = CHAN_AGENT;   /* identify channel type */
        c->u.a.lensofar = 0;
        c->u.a.message = NULL;
+       c->u.a.outstanding_requests = 0;
        add234(ssh->channels, c);
        send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
                    PKT_INT, c->remoteid, PKT_INT, c->localid,
@@ -5060,6 +5061,7 @@ static void ssh1_msg_channel_data(Ssh ssh, struct Packet *pktin)
                if (c->u.a.lensofar == c->u.a.totallen) {
                    void *reply;
                    int replylen;
+                    c->u.a.outstanding_requests++;
                    if (agent_query(c->u.a.message,
                                    c->u.a.totallen,
                                    &reply, &replylen,
@@ -6580,6 +6582,21 @@ static void ssh2_channel_init(struct ssh_channel *c)
 }
 
 /*
+ * Construct the common parts of a CHANNEL_OPEN.
+ */
+static struct Packet *ssh2_chanopen_init(struct ssh_channel *c, char *type)
+{
+    struct Packet *pktout;
+
+    pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
+    ssh2_pkt_addstring(pktout, type);
+    ssh2_pkt_adduint32(pktout, c->localid);
+    ssh2_pkt_adduint32(pktout, c->v.v2.locwindow);/* our window size */
+    ssh2_pkt_adduint32(pktout, OUR_V2_MAXPKT);      /* our max pkt size */
+    return pktout;
+}
+
+/*
  * CHANNEL_FAILURE doesn't come with any indication of what message
  * caused it, so we have to keep track of the outstanding
  * CHANNEL_REQUESTs ourselves.
@@ -6840,6 +6857,7 @@ static void ssh2_msg_channel_data(Ssh ssh, struct Packet *pktin)
                if (c->u.a.lensofar == c->u.a.totallen) {
                    void *reply;
                    int replylen;
+                    c->u.a.outstanding_requests++;
                    if (agent_query(c->u.a.message,
                                    c->u.a.totallen,
                                    &reply, &replylen,
@@ -6978,8 +6996,10 @@ static void ssh2_channel_got_eof(struct ssh_channel *c)
     if (c->type == CHAN_X11) {
        x11_send_eof(c->u.x11.s);
     } else if (c->type == CHAN_AGENT) {
-        /* Manufacture an outgoing EOF in response to the incoming one. */
-        sshfwd_write_eof(c);
+        if (c->u.a.outstanding_requests == 0) {
+            /* Manufacture an outgoing EOF in response to the incoming one. */
+            sshfwd_write_eof(c);
+        }
     } else if (c->type == CHAN_SOCKDATA) {
        pfd_send_eof(c->u.pfd.s);
     } else if (c->type == CHAN_MAINSESSION) {
@@ -7401,6 +7421,7 @@ static void ssh2_msg_channel_open(Ssh ssh, struct Packet *pktin)
        else {
            c->type = CHAN_AGENT;       /* identify channel type */
            c->u.a.lensofar = 0;
+            c->u.a.outstanding_requests = 0;
        }
     } else {
        error = "Unsupported channel type requested";
@@ -9121,11 +9142,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
                  "Opening direct-tcpip channel to %s:%d in place of session",
                  conf_get_str(ssh->conf, CONF_ssh_nc_host),
                  conf_get_int(ssh->conf, CONF_ssh_nc_port));
-       s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
-       ssh2_pkt_addstring(s->pktout, "direct-tcpip");
-       ssh2_pkt_adduint32(s->pktout, ssh->mainchan->localid);
-       ssh2_pkt_adduint32(s->pktout, ssh->mainchan->v.v2.locwindow);/* our window size */
-       ssh2_pkt_adduint32(s->pktout, OUR_V2_MAXPKT);      /* our max pkt size */
+       s->pktout = ssh2_chanopen_init(ssh->mainchan, "direct-tcpip");
        ssh2_pkt_addstring(s->pktout, conf_get_str(ssh->conf, CONF_ssh_nc_host));
        ssh2_pkt_adduint32(s->pktout, conf_get_int(ssh->conf, CONF_ssh_nc_port));
        /*
@@ -9160,11 +9177,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
        ssh->mainchan = snew(struct ssh_channel);
        ssh->mainchan->ssh = ssh;
        ssh2_channel_init(ssh->mainchan);
-       s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
-       ssh2_pkt_addstring(s->pktout, "session");
-       ssh2_pkt_adduint32(s->pktout, ssh->mainchan->localid);
-       ssh2_pkt_adduint32(s->pktout, ssh->mainchan->v.v2.locwindow);/* our window size */
-       ssh2_pkt_adduint32(s->pktout, OUR_V2_MAXPKT);    /* our max pkt size */
+       s->pktout = ssh2_chanopen_init(ssh->mainchan, "session");
        ssh2_pkt_send(ssh, s->pktout);
        crWaitUntilV(pktin);
        if (pktin->type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
@@ -10155,11 +10168,7 @@ void ssh_send_port_open(void *channel, char *hostname, int port, char *org)
                    /* PKT_STR, <org:orgport>, */
                    PKT_END);
     } else {
-       pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
-       ssh2_pkt_addstring(pktout, "direct-tcpip");
-       ssh2_pkt_adduint32(pktout, c->localid);
-       ssh2_pkt_adduint32(pktout, c->v.v2.locwindow);/* our window size */
-       ssh2_pkt_adduint32(pktout, OUR_V2_MAXPKT);      /* our max pkt size */
+       pktout = ssh2_chanopen_init(c, "direct-tcpip");
        ssh2_pkt_addstring(pktout, hostname);
        ssh2_pkt_adduint32(pktout, port);
        /*