upstream: Add Escape option ~I that shows information about the current

SSH connection. ok djm@, "I like/want" sthen@ florian@

OpenBSD-Commit-ID: 0483fc0188ec899077e4bc8e1e353f7dfa9f5c1d
This commit is contained in:
dtucker@openbsd.org
2025-11-27 02:18:48 +00:00
committed by Darren Tucker
parent 0fb1f3c995
commit 52037ed910
4 changed files with 125 additions and 5 deletions

View File

@@ -1,4 +1,4 @@
/* $OpenBSD: clientloop.c,v 1.417 2025/10/16 00:00:36 djm Exp $ */
/* $OpenBSD: clientloop.c,v 1.418 2025/11/27 02:18:48 dtucker Exp $ */
/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -1125,6 +1125,7 @@ static struct escape_help_text esc_txt[] = {
SUPPRESS_MUXCLIENT},
{"B", "send a BREAK to the remote system", SUPPRESS_NEVER},
{"C", "open a command line", SUPPRESS_MUXCLIENT|SUPPRESS_NOCMDLINE},
{"I", "show connection information", SUPPRESS_NEVER},
{"R", "request rekey", SUPPRESS_NEVER},
{"V/v", "decrease/increase verbosity (LogLevel)", SUPPRESS_MUXCLIENT},
{"^Z", "suspend ssh", SUPPRESS_MUXCLIENT},
@@ -1247,6 +1248,16 @@ process_escapes(struct ssh *ssh, Channel *c,
fatal_fr(r, "send packet");
continue;
case 'I':
if ((r = sshbuf_putf(berr, "%cI\r\n",
efc->escape_char)) != 0)
fatal_fr(r, "sshbuf_putf");
s = connection_info_message(ssh);
if ((r = sshbuf_put(berr, s, strlen(s))) != 0)
fatal_fr(r, "sshbuf_put");
free(s);
continue;
case 'R':
if (ssh->compat & SSH_BUG_NOREKEY)
logit("Server does not "

108
packet.c
View File

@@ -1,4 +1,4 @@
/* $OpenBSD: packet.c,v 1.323 2025/09/25 06:33:19 djm Exp $ */
/* $OpenBSD: packet.c,v 1.324 2025/11/27 02:18:48 dtucker Exp $ */
/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -59,6 +59,7 @@
#include <poll.h>
#include <signal.h>
#include <time.h>
#include <util.h>
/*
* Explicitly include OpenSSL before zlib as some versions of OpenSSL have
@@ -2902,3 +2903,108 @@ sshpkt_add_padding(struct ssh *ssh, u_char pad)
ssh->state->extra_pad = pad;
return 0;
}
static char *
format_traffic_stats(struct packet_state *ps)
{
char *stats = NULL, bytes[FMT_SCALED_STRSIZE];
if (ps->bytes > LLONG_MAX || fmt_scaled(ps->bytes, bytes) != 0)
strlcpy(bytes, "OVERFLOW", sizeof(bytes));
xasprintf(&stats, "%lu pkts %llu blks %sB",
(unsigned long)ps->packets, (unsigned long long)ps->blocks, bytes);
return stats;
}
static char *
dedupe_alg_names(const char *in, const char *out)
{
char *names = NULL;
if (in == NULL)
in = "<implicit>";
if (out == NULL)
out = "<implicit>";
if (strcmp(in, out) == 0) {
names = xstrdup(in);
} else {
xasprintf(&names, "%s in, %s out", in, out);
}
return names;
}
char *
connection_info_message(struct ssh *ssh)
{
char *ret = NULL, *cipher = NULL, *mac = NULL, *comp = NULL;
char *rekey_volume = NULL, *rekey_time = NULL;
struct kex *kex;
struct session_state *state;
struct newkeys *nk_in, *nk_out;
char *stats_in = NULL, *stats_out = NULL;
u_int64_t epoch = (u_int64_t)time(NULL) - monotime();
if (ssh == NULL)
return NULL;
state = ssh->state;
kex = ssh->kex;
nk_in = ssh->state->newkeys[MODE_IN];
nk_out = ssh->state->newkeys[MODE_OUT];
stats_in = format_traffic_stats(&ssh->state->p_read);
stats_out = format_traffic_stats(&ssh->state->p_send);
cipher = dedupe_alg_names(nk_in->enc.name, nk_out->enc.name);
mac = dedupe_alg_names(nk_in->mac.name, nk_out->mac.name);
comp = dedupe_alg_names(nk_in->comp.name, nk_out->comp.name);
/* Volume based rekeying. */
if (state->rekey_limit == 0) {
xasprintf(&rekey_volume, "limit none");
} else {
char *volumes = NULL, in[32], out[32];
snprintf(in, sizeof(in), "%llu",
(unsigned long long)state->max_blocks_in);
snprintf(out, sizeof(out), "%llu",
(unsigned long long)state->max_blocks_out);
volumes = dedupe_alg_names(in, out);
xasprintf(&rekey_volume, "limit blocks %s", volumes);
free(volumes);
}
/* Time based rekeying. */
if (state->rekey_interval == 0) {
rekey_time = xstrdup("interval none");
} else {
char rekey_next[64];
format_absolute_time(epoch + state->rekey_time +
state->rekey_interval, rekey_next, sizeof(rekey_next));
xasprintf(&rekey_time, "interval %s, next %s",
fmt_timeframe(state->rekey_interval), rekey_next);
}
xasprintf(&ret, "Connection information for peer %s port %d:\r\n"
" kexalgorithm %s\r\n hostkeyalgorithm %s\r\n"
" cipher %s\r\n mac %s\r\n compression %s\r\n"
" rekey %s %s\r\n"
" traffic %s in, %s out\r\n",
ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
kex->name, kex->hostkey_alg,
cipher, mac, comp,
rekey_volume, rekey_time,
stats_in, stats_out
);
free(cipher);
free(mac);
free(comp);
free(stats_in);
free(stats_out);
free(rekey_volume);
free(rekey_time);
return ret;
}

View File

@@ -1,4 +1,4 @@
/* $OpenBSD: packet.h,v 1.103 2025/09/25 06:33:19 djm Exp $ */
/* $OpenBSD: packet.h,v 1.104 2025/11/27 02:18:48 dtucker Exp $ */
/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
@@ -210,6 +210,7 @@ int sshpkt_get_bignum2(struct ssh *ssh, BIGNUM **valp);
int sshpkt_get_end(struct ssh *ssh);
void sshpkt_fmt_connection_id(struct ssh *ssh, char *s, size_t l);
const u_char *sshpkt_ptr(struct ssh *, size_t *lenp);
char *connection_info_message(struct ssh *ssh);
#if !defined(WITH_OPENSSL)
# undef BIGNUM

6
ssh.1
View File

@@ -33,8 +33,8 @@
.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
.\"
.\" $OpenBSD: ssh.1,v 1.444 2024/12/04 14:37:55 djm Exp $
.Dd $Mdocdate: December 4 2024 $
.\" $OpenBSD: ssh.1,v 1.445 2025/11/27 02:18:48 dtucker Exp $
.Dd $Mdocdate: November 27 2025 $
.Dt SSH 1
.Os
.Sh NAME
@@ -1156,6 +1156,8 @@ option is enabled in
Basic help is available, using the
.Fl h
option.
.It Cm ~I
Show information about the current SSH connection.
.It Cm ~R
Request rekeying of the connection
(only useful if the peer supports it).