* Hence, in SSH 1 this structure is indexed by destination
* host:port pair, whereas in SSH 2 it is indexed by source port.
*/
+struct ssh_portfwd; /* forward declaration */
+
struct ssh_rportfwd {
unsigned sport, dport;
char dhost[256];
char *sportdesc;
+ struct ssh_portfwd *pfrec;
};
+#define free_rportfwd(pf) ( \
+ ((pf) ? (sfree((pf)->sportdesc)) : (void)0 ), sfree(pf) )
+
+/*
+ * Separately to the rportfwd tree (which is for looking up port
+ * open requests from the server), a tree of _these_ structures is
+ * used to keep track of all the currently open port forwardings,
+ * so that we can reconfigure in mid-session if the user requests
+ * it.
+ */
+struct ssh_portfwd {
+ int keep;
+ int type;
+ unsigned sport, dport;
+ char *saddr, *daddr;
+ struct ssh_rportfwd *remote;
+ void *local;
+};
+#define free_portfwd(pf) ( \
+ ((pf) ? (sfree((pf)->saddr), sfree((pf)->daddr)) : (void)0 ), sfree(pf) )
struct Packet {
long length;
struct ssh_channel *mainchan; /* primary session channel */
int exitcode;
- tree234 *rportfwds;
+ tree234 *rportfwds, *portfwds;
enum {
SSH_STATE_PREPACKET,
return 0;
}
+/*
+ * Special form of strcmp which can cope with NULL inputs. NULL is
+ * defined to sort before even the empty string.
+ */
+static int nullstrcmp(const char *a, const char *b)
+{
+ if (a == NULL && b == NULL)
+ return 0;
+ if (a == NULL)
+ return -1;
+ if (b == NULL)
+ return +1;
+ return strcmp(a, b);
+}
+
+static int ssh_portcmp(void *av, void *bv)
+{
+ struct ssh_portfwd *a = (struct ssh_portfwd *) av;
+ struct ssh_portfwd *b = (struct ssh_portfwd *) bv;
+ int i;
+ if (a->type > b->type)
+ return +1;
+ if (a->type < b->type)
+ return -1;
+ if ( (i = nullstrcmp(a->saddr, b->saddr)) != 0)
+ return i < 0 ? -1 : +1;
+ if (a->sport > b->sport)
+ return +1;
+ if (a->sport < b->sport)
+ return -1;
+ if (a->type != 'D') {
+ if ( (i = nullstrcmp(a->daddr, b->daddr)) != 0)
+ return i < 0 ? -1 : +1;
+ if (a->dport > b->dport)
+ return +1;
+ if (a->dport < b->dport)
+ return -1;
+ }
+ return 0;
+}
+
static int alloc_channel_id(Ssh ssh)
{
const unsigned CHANNEL_NUMBER_OFFSET = 256;
rpf = del234(ssh->rportfwds, pf);
assert(rpf == pf);
- sfree(pf->sportdesc);
- sfree(pf);
+ free_rportfwd(pf);
}
}
portfwd_strptr = cfg->portfwd;
+ if (!ssh->portfwds) {
+ ssh->portfwds = newtree234(ssh_portcmp);
+ } else {
+ /*
+ * Go through the existing port forwardings and tag them
+ * with keep==FALSE. Any that we want to keep will be
+ * re-enabled as we go through the configuration and find
+ * out which bits are the same as they were before.
+ */
+ struct ssh_portfwd *epf;
+ int i;
+ for (i = 0; (epf = index234(ssh->portfwds, i)) != NULL; i++)
+ epf->keep = FALSE;
+ }
+
while (*portfwd_strptr) {
type = *portfwd_strptr++;
saddr[0] = '\0';
}
if (sport && dport) {
/* Set up a description of the source port. */
- static char *sportdesc;
+ struct ssh_portfwd *pfrec, *epfrec;
+ char *sportdesc;
sportdesc = dupprintf("%.*s%.*s%.*s%.*s%d%.*s",
(int)(*saddr?strlen(saddr):0), *saddr?saddr:NULL,
(int)(*saddr?1:0), ":",
(int)(sserv ? strlen(sports) : 0), sports,
sserv, "(", sport, sserv, ")");
- if (type == 'L') {
+
+ pfrec = snew(struct ssh_portfwd);
+ pfrec->type = type;
+ pfrec->saddr = *saddr ? dupstr(saddr) : NULL;
+ pfrec->sport = sport;
+ pfrec->daddr = dupstr(host);
+ pfrec->dport = dport;
+ pfrec->local = NULL;
+ pfrec->remote = NULL;
+
+ epfrec = add234(ssh->portfwds, pfrec);
+ if (epfrec != pfrec) {
+ /*
+ * We already have a port forwarding with precisely
+ * these parameters. Hence, no need to do anything;
+ * simply tag the existing one as `keep'.
+ */
+ epfrec->keep = TRUE;
+ free_portfwd(pfrec);
+ } else if (type == 'L') {
/* Verbose description of the destination port */
char *dportdesc = dupprintf("%s:%.*s%.*s%d%.*s",
host,
dserv, "(", dport, dserv, ")");
const char *err = pfd_addforward(host, dport,
*saddr ? saddr : NULL,
- sport, ssh, &ssh->cfg);
+ sport, ssh, &ssh->cfg,
+ &pfrec->local);
if (err) {
logeventf(ssh, "Local port %s forward to %s"
" failed: %s", sportdesc, dportdesc, err);
} else if (type == 'D') {
const char *err = pfd_addforward(NULL, -1,
*saddr ? saddr : NULL,
- sport, ssh, &ssh->cfg);
+ sport, ssh, &ssh->cfg,
+ &pfrec->local);
if (err) {
logeventf(ssh, "Local port %s SOCKS dynamic forward"
" setup failed: %s", sportdesc, err);
pf->sportdesc = sportdesc;
sportdesc = NULL;
+ pfrec->remote = pf;
+ pf->pfrec = pfrec;
if (ssh->version == 1) {
send_packet(ssh, SSH1_CMSG_PORT_FORWARD_REQUEST,
sfree(sportdesc);
}
}
+
+ /*
+ * Now go through and destroy any port forwardings which were
+ * not re-enabled.
+ */
+ {
+ struct ssh_portfwd *epf;
+ int i;
+ for (i = 0; (epf = index234(ssh->portfwds, i)) != NULL; i++)
+ if (!epf->keep) {
+ char *message;
+
+ message = dupprintf("%s port forwarding from %s%s%d",
+ epf->type == 'L' ? "local" :
+ epf->type == 'R' ? "remote" : "dynamic",
+ epf->saddr ? epf->saddr : "",
+ epf->saddr ? ":" : "",
+ epf->sport);
+
+ if (epf->type != 'D') {
+ char *msg2 = dupprintf("%s to %s:%d", message,
+ epf->daddr, epf->dport);
+ sfree(message);
+ message = msg2;
+ }
+
+ logeventf(ssh, "Cancelling %s", message);
+ sfree(message);
+
+ if (epf->remote) {
+ struct ssh_rportfwd *rpf = epf->remote;
+ struct Packet *pktout;
+
+ /*
+ * Cancel the port forwarding at the server
+ * end.
+ */
+ if (ssh->version == 1) {
+ /*
+ * We cannot cancel listening ports on the
+ * server side in SSH1! There's no message
+ * to support it. Instead, we simply remove
+ * the rportfwd record from the local end
+ * so that any connections the server tries
+ * to make on it are rejected.
+ */
+ } else {
+ pktout = ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST);
+ ssh2_pkt_addstring(pktout, "cancel-tcpip-forward");
+ ssh2_pkt_addbool(pktout, 0);/* _don't_ want reply */
+ if (epf->saddr) {
+ ssh2_pkt_addstring(pktout, epf->saddr);
+ } else if (ssh->cfg.rport_acceptall) {
+ ssh2_pkt_addstring(pktout, "0.0.0.0");
+ } else {
+ ssh2_pkt_addstring(pktout, "127.0.0.1");
+ }
+ ssh2_pkt_adduint32(pktout, epf->sport);
+ ssh2_pkt_send(ssh, pktout);
+ }
+
+ del234(ssh->rportfwds, rpf);
+ free_rportfwd(rpf);
+ } else if (epf->local) {
+ pfd_terminate(epf->local);
+ }
+
+ delpos234(ssh->portfwds, i);
+ free_portfwd(epf);
+ i--; /* so we don't skip one in the list */
+ }
+ }
}
static void ssh1_smsg_stdout_stderr_data(Ssh ssh, struct Packet *pktin)
/*
* Reconfigure the SSH backend.
- *
- * Currently, this function does nothing very useful. In future,
- * however, we could do some handy things with it. For example, we
- * could make the port forwarding configurer active in the Change
- * Settings box, and this routine could close down existing
- * forwardings and open up new ones in response to changes.
*/
static void ssh_reconfig(void *handle, Config *cfg)
{
Ssh ssh = (Ssh) handle;
pinger_reconfig(ssh->pinger, &ssh->cfg, cfg);
+ ssh_setup_portfwd(ssh, cfg);
ssh->cfg = *cfg; /* STRUCTURE COPY */
}
projects / u / mdw / putty / blobdiff