1
0
mirror of https://git.tartarus.org/simon/putty.git synced 2025-01-08 08:58:00 +00:00
putty-source/noproxy.c
Simon Tatham 6d272ee007 Allow new_connection to take an optional Seat. (NFC)
This is working towards allowing the subsidiary SSH connection in an
SshProxy to share the main user-facing Seat, so as to be able to pass
through interactive prompts.

This is more difficult than the similar change with LogPolicy, because
Seats are stateful. In particular, the trust-sigil status will need to
be controlled by the SshProxy until it's ready to pass over control to
the main SSH (or whatever) connection.

To make this work, I've introduced a thing called a TempSeat, which is
(yet) another Seat implementation. When a backend hands its Seat to
new_connection(), it does it in a way that allows new_connection() to
borrow it completely, and replace it in the main backend structure
with a TempSeat, which acts as a temporary placeholder. If the main
backend tries to do things like changing trust status or sending
output, the TempSeat will buffer them; later on, when the connection
is established, TempSeat will replay the changes into the real Seat.

So, in each backend, I've made the following changes:
 - pass &foo->seat to new_connection, which may overwrite it with a
   TempSeat.
 - if it has done so (which we can tell via the is_tempseat() query
   function), then we have to free the TempSeat and reinstate our main
   Seat. The signal that we can do so is the PLUGLOG_CONNECT_SUCCESS
   notification, which indicates that SshProxy has finished all its
   connection setup work.
 - we also have to remember to free the TempSeat if our backend is
   disposed of without that having happened (e.g. because the
   connection _doesn't_ succeed).
 - in backends which have no local auth phase to worry about, ensure
   we don't call seat_set_trust_status on the main Seat _before_ it
   gets potentially replaced with a TempSeat. Moved some calls of
   seat_set_trust_status to just after new_connection(), so that now
   the initial trust status setup will go into the TempSeat (if
   appropriate) and be buffered until that seat is relinquished.

In all other uses of new_connection, where we don't have a Seat
available at all, we just pass NULL.

This is NFC, because neither new_connection() nor any of its delegates
will _actually_ do this replacement yet. We're just setting up the
framework to enable it to do so in the next commit.
2021-09-13 17:24:47 +01:00

33 lines
1.2 KiB
C

/*
* noproxy.c: an alternative to proxy.c, for use by auxiliary programs
* that need to make network connections but don't want to include all
* the full-on support for endless network proxies (and its
* configuration requirements). Implements the primary APIs of
* proxy.c, but maps them straight to the underlying network layer.
*/
#include "putty.h"
#include "network.h"
#include "proxy.h"
SockAddr *name_lookup(const char *host, int port, char **canonicalname,
Conf *conf, int addressfamily, LogContext *logctx,
const char *reason)
{
return sk_namelookup(host, canonicalname, addressfamily);
}
Socket *new_connection(SockAddr *addr, const char *hostname,
int port, bool privport,
bool oobinline, bool nodelay, bool keepalive,
Plug *plug, Conf *conf, LogPolicy *lp, Seat **seat)
{
return sk_new(addr, port, privport, oobinline, nodelay, keepalive, plug);
}
Socket *new_listener(const char *srcaddr, int port, Plug *plug,
bool local_host_only, Conf *conf, int addressfamily)
{
return sk_newlistener(srcaddr, port, plug, local_host_only, addressfamily);
}