зеркало из https://github.com/github/putty.git
Add a preference list for SSH-2 key exchange algorithms, on a new "Kex" panel
(which will gain more content anon). Retire BUG_SSH2_DH_GEX and add a backwards-compatibility wart, since we never did find a way of automatically detecting this alleged server bug, and in any case there was only ever one report (<3D91F3B5.7030309@inwind.it>, FWIW). Also generalise askcipher() to a new askalg() (thus touching all the front-ends). I've made some attempt to document what SSH key exchange is and why you care, but it could use some review for clarity (and outright lies). [originally from svn r5022]
This commit is contained in:
Jacob Nevins
Родитель
f13f9f6420
Коммит
3c98d6e60d
64
config.c
64
config.c
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@ -124,6 +124,48 @@ static void cipherlist_handler(union control *ctrl, void *dlg,
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}
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}
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static void kexlist_handler(union control *ctrl, void *dlg,
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void *data, int event)
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{
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Config *cfg = (Config *)data;
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if (event == EVENT_REFRESH) {
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int i;
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static const struct { char *s; int k; } kexes[] = {
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{ "Diffie-Hellman group 1", KEX_DHGROUP1 },
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{ "Diffie-Hellman group 14", KEX_DHGROUP14 },
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{ "Diffie-Hellman group exchange", KEX_DHGEX },
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{ "-- warn below here --", KEX_WARN }
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};
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/* Set up the "kex preference" box. */
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/* (kexlist assumed to contain all algorithms) */
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dlg_update_start(ctrl, dlg);
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dlg_listbox_clear(ctrl, dlg);
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for (i = 0; i < KEX_MAX; i++) {
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int k = cfg->ssh_kexlist[i];
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int j;
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char *kstr = NULL;
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for (j = 0; j < (sizeof kexes) / (sizeof kexes[0]); j++) {
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if (kexes[j].k == k) {
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kstr = kexes[j].s;
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break;
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}
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}
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dlg_listbox_addwithid(ctrl, dlg, kstr, k);
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}
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dlg_update_done(ctrl, dlg);
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} else if (event == EVENT_VALCHANGE) {
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int i;
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/* Update array to match the list box. */
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for (i=0; i < KEX_MAX; i++)
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cfg->ssh_kexlist[i] = dlg_listbox_getid(ctrl, dlg, i);
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}
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}
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static void printerbox_handler(union control *ctrl, void *dlg,
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void *data, int event)
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{
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@ -1525,6 +1567,25 @@ void setup_config_box(struct controlbox *b, struct sesslist *sesslist,
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dlg_stdcheckbox_handler,
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I(offsetof(Config,ssh2_des_cbc)));
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/*
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* The Connection/SSH/Kex panel.
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*/
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ctrl_settitle(b, "Connection/SSH/Kex",
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"Options controlling SSH key exchange");
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s = ctrl_getset(b, "Connection/SSH/Kex", "main",
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"Key exchange algorithm options");
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c = ctrl_draglist(s, "Algorithm selection policy", 's',
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HELPCTX(ssh_kexlist),
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kexlist_handler, P(NULL));
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c->listbox.height = 5;
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#if 0
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s = ctrl_getset(b, "Connection/SSH/Kex", "repeat",
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"Options controlling key re-exchange");
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/* FIXME: at least time and data size */
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#endif
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/*
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* The Connection/SSH/Auth panel.
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*/
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@ -1659,9 +1720,6 @@ void setup_config_box(struct controlbox *b, struct sesslist *sesslist,
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ctrl_droplist(s, "Requires padding on SSH2 RSA signatures", 'p', 20,
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HELPCTX(ssh_bugs_rsapad2),
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sshbug_handler, I(offsetof(Config,sshbug_rsapad2)));
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ctrl_droplist(s, "Chokes on Diffie-Hellman group exchange", 'd', 20,
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HELPCTX(ssh_bugs_dhgex2),
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sshbug_handler, I(offsetof(Config,sshbug_dhgex2)));
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ctrl_droplist(s, "Misuses the session ID in PK auth", 'n', 20,
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HELPCTX(ssh_bugs_pksessid2),
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sshbug_handler, I(offsetof(Config,sshbug_pksessid2)));
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@ -2098,6 +2098,77 @@ these servers if you enable the \q{Enable legacy use of single-DES in
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SSH 2} option; by default this is disabled and PuTTY will stick to
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recommended ciphers.
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\H{config-ssh-kex} The Kex panel
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\# FIXME: This whole section is draft. Feel free to revise.
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The Kex panel (short for \q{key exchange}) allows you to configure
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options related to SSH-2 key exchange.
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Key exchange occurs at the start of an SSH connection (and
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occasionally thereafter); it establishes a shared secret that is used
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as the basis for all of SSH's security features. It is therefore very
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important for the security of the connection that the key exchange is
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secure.
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Key exchange is a cryptographically intensive process; if either the
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client or the server is a relatively slow machine, the slower methods
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may take several tens of seconds to complete.
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If connection startup is too slow, or the connection hangs
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periodically, you may want to try changing these settings.
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If you don't understand what any of this means, it's safe to leave
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these settings alone.
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This entire panel is only relevant to SSH protocol version 2; none of
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these settings affect SSH-1 at all.
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\S{config-ssh-kex-order} Key exchange algorithm selection
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\cfg{winhelp-topic}{ssh.kex.order}
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PuTTY supports a variety of SSH-2 key exchange methods, and allows you
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to choose which one you prefer to use; configuration is similar to
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cipher selection (see \k{config-ssh-encryption}).
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PuTTY currently supports the following varieties of Diffie-Hellman key
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exchange:
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\b \q{Group 14}: a well-known 2048-bit group.
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\b \q{Group 1}: a well-known 1024-bit group. This is less secure
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\#{FIXME better words} than group 14, but may be faster with slow
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client or server machines, and may be the only method supported by
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older server software.
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\b \q{Group exchange}: with this method, instead of using a fixed
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group, PuTTY requests that the server suggest a group to use for key
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exchange; the server can avoid groups known to be weak, and possibly
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invent new ones over time, without any changes required to PuTTY's
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configuration. We recommend use of this method, if possible.
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If the first algorithm PuTTY finds is below the \q{warn below here}
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line, you will see a warning box when you make the connection, similar
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to that for cipher selection (see \k{config-ssh-encryption}).
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\# [Repeat key exchange bumph when config is added:] If the session
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key negotiated at connection startup is used too much or for too long,
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it may become feasible to mount attacks against the SSH connection.
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Therefore, the SSH protocol specifies that a new key exchange should
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take place every so often.
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\# While this renegotiation is taking place, no data can pass through
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the SSH connection, so it may appear to \q{freeze}. (The occurrence of
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repeat key exchange is noted in the Event Log; see
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\k{using-eventlog}.) Usually the same algorithm is used as at the
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start of the connection, with a similar overhead.
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\# [When options are added to frob how often this happens, we should
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hardcode the values recommended by the drafts -- 1 hour, 1GB -- in
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this documentation, in case PuTTY's defaults are obscured by Default
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Settings etc. Assuming we think they're good advice, that is.]
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\H{config-ssh-auth} The Auth panel
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The Auth panel allows you to configure authentication options for
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@ -2455,23 +2526,6 @@ to talking to OpenSSH.
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This is an SSH2-specific bug.
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\S{config-ssh-bug-dhgex} \q{Chokes on Diffie-Hellman group exchange}
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\cfg{winhelp-topic}{ssh.bugs.dhgex2}
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We have anecdotal evidence that some SSH servers claim to be able to
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perform Diffie-Hellman group exchange, but fail to actually do so
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when PuTTY tries to. If your SSH2 sessions spontaneously close
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immediately after opening the PuTTY window, it might be worth
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enabling the workaround for this bug to see if it helps.
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We have no hard evidence that any specific version of specific
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server software reliably demonstrates this bug. Therefore, PuTTY
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will never \e{assume} a server has this bug; if you want the
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workaround, you need to enable it manually.
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This is an SSH2-specific bug.
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\S{config-ssh-bug-pksessid2} \q{Misuses the session ID in PK auth}
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\cfg{winhelp-topic}{ssh.bugs.pksessid2}
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@ -1,4 +1,4 @@
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/* $Id: mac.c,v 1.59 2003/05/10 12:27:38 ben Exp $ */
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/* $Id$ */
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/*
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* Copyright (c) 1999, 2003 Ben Harris
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* All rights reserved.
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@ -704,7 +704,7 @@ void verify_ssh_host_key(void *frontend, char *host, int port, char *keytype,
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}
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}
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void askcipher(void *frontend, char *ciphername, int cs)
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void askalg(void *frontend, const char *algtype, const char *algname)
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{
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}
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16
putty.h
16
putty.h
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@ -232,6 +232,17 @@ enum {
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VT_XWINDOWS, VT_OEMANSI, VT_OEMONLY, VT_POORMAN, VT_UNICODE
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};
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enum {
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/*
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* SSH-2 key exchange algorithms
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*/
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KEX_WARN,
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KEX_DHGROUP1,
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KEX_DHGROUP14,
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KEX_DHGEX,
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KEX_MAX
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};
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enum {
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/*
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* SSH ciphers (both SSH1 and SSH2)
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@ -388,6 +399,7 @@ struct config_tag {
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* but never for loading/saving */
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int nopty;
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int compression;
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int ssh_kexlist[KEX_MAX];
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int agentfwd;
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int change_username; /* allow username switching in SSH2 */
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int ssh_cipherlist[CIPHER_MAX];
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@ -514,7 +526,7 @@ struct config_tag {
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/* SSH bug compatibility modes */
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int sshbug_ignore1, sshbug_plainpw1, sshbug_rsa1,
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sshbug_hmac2, sshbug_derivekey2, sshbug_rsapad2,
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sshbug_dhgex2, sshbug_pksessid2;
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sshbug_pksessid2;
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/* Options for pterm. Should split out into platform-dependent part. */
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int stamp_utmp;
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int login_shell;
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@ -862,7 +874,7 @@ int wc_unescape(char *output, const char *wildcard);
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void logevent(void *frontend, const char *);
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void verify_ssh_host_key(void *frontend, char *host, int port, char *keytype,
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char *keystr, char *fingerprint);
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void askcipher(void *frontend, char *ciphername, int cs);
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void askalg(void *frontend, const char *algtype, const char *algname);
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int askappend(void *frontend, Filename filename);
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/*
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|
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25
settings.c
25
settings.c
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@ -12,6 +12,7 @@
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*/
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struct keyval { char *s; int v; };
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/* The cipher order given here is the default order. */
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static const struct keyval ciphernames[] = {
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{ "aes", CIPHER_AES },
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{ "blowfish", CIPHER_BLOWFISH },
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@ -20,6 +21,13 @@ static const struct keyval ciphernames[] = {
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{ "des", CIPHER_DES }
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};
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static const struct keyval kexnames[] = {
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{ "dh-gex-sha1", KEX_DHGEX },
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{ "dh-group14-sha1", KEX_DHGROUP14 },
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{ "dh-group1-sha1", KEX_DHGROUP1 },
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{ "WARN", KEX_WARN }
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};
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static void gpps(void *handle, const char *name, const char *def,
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char *val, int len)
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{
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@ -227,6 +235,7 @@ void save_open_settings(void *sesskey, int do_host, Config *cfg)
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write_setting_i(sesskey, "ChangeUsername", cfg->change_username);
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wprefs(sesskey, "Cipher", ciphernames, CIPHER_MAX,
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cfg->ssh_cipherlist);
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wprefs(sesskey, "KEX", kexnames, KEX_MAX, cfg->ssh_kexlist);
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write_setting_i(sesskey, "AuthTIS", cfg->try_tis_auth);
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write_setting_i(sesskey, "AuthKI", cfg->try_ki_auth);
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write_setting_i(sesskey, "SshNoShell", cfg->ssh_no_shell);
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@ -358,7 +367,6 @@ void save_open_settings(void *sesskey, int do_host, Config *cfg)
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write_setting_i(sesskey, "BugHMAC2", 2-cfg->sshbug_hmac2);
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write_setting_i(sesskey, "BugDeriveKey2", 2-cfg->sshbug_derivekey2);
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write_setting_i(sesskey, "BugRSAPad2", 2-cfg->sshbug_rsapad2);
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write_setting_i(sesskey, "BugDHGEx2", 2-cfg->sshbug_dhgex2);
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write_setting_i(sesskey, "BugPKSessID2", 2-cfg->sshbug_pksessid2);
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write_setting_i(sesskey, "StampUtmp", cfg->stamp_utmp);
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write_setting_i(sesskey, "LoginShell", cfg->login_shell);
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@ -492,6 +500,20 @@ void load_open_settings(void *sesskey, int do_host, Config *cfg)
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gppi(sesskey, "ChangeUsername", 0, &cfg->change_username);
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gprefs(sesskey, "Cipher", "\0",
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ciphernames, CIPHER_MAX, cfg->ssh_cipherlist);
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{
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/* Backward-compatibility: we used to have an option to
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* disable gex under the "bugs" panel after one report of
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* a server which offered it then choked, but we never got
|
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* a server version string or any other reports. */
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char *default_kexes;
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gppi(sesskey, "BugDHGEx2", 0, &i); i = 2-i;
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if (i == FORCE_ON)
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default_kexes = "dh-group14-sha1,dh-group1-sha1,WARN,dh-gex-sha1";
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else
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default_kexes = "dh-gex-sha1,dh-group14-sha1,dh-group1-sha1,WARN";
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gprefs(sesskey, "KEX", default_kexes,
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kexnames, KEX_MAX, cfg->ssh_kexlist);
|
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}
|
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gppi(sesskey, "SshProt", 2, &cfg->sshprot);
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gppi(sesskey, "SSH2DES", 0, &cfg->ssh2_des_cbc);
|
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gppi(sesskey, "AuthTIS", 0, &cfg->try_tis_auth);
|
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|
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@ -667,7 +689,6 @@ void load_open_settings(void *sesskey, int do_host, Config *cfg)
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}
|
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gppi(sesskey, "BugDeriveKey2", 0, &i); cfg->sshbug_derivekey2 = 2-i;
|
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gppi(sesskey, "BugRSAPad2", 0, &i); cfg->sshbug_rsapad2 = 2-i;
|
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gppi(sesskey, "BugDHGEx2", 0, &i); cfg->sshbug_dhgex2 = 2-i;
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gppi(sesskey, "BugPKSessID2", 0, &i); cfg->sshbug_pksessid2 = 2-i;
|
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gppi(sesskey, "StampUtmp", 1, &cfg->stamp_utmp);
|
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gppi(sesskey, "LoginShell", 1, &cfg->login_shell);
|
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|
|
|
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107
ssh.c
107
ssh.c
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|
@ -162,7 +162,7 @@ static const char *const ssh2_disconnect_reasons[] = {
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#define BUG_CHOKES_ON_RSA 8
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#define BUG_SSH2_RSA_PADDING 16
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#define BUG_SSH2_DERIVEKEY 32
|
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#define BUG_SSH2_DH_GEX 64
|
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/* 64 was BUG_SSH2_DH_GEX, now spare */
|
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#define BUG_SSH2_PK_SESSIONID 128
|
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|
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#define translate(x) if (type == x) return #x
|
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|
|
@ -360,12 +360,6 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
|
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#define SSH_MAX_BACKLOG 32768
|
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#define OUR_V2_WINSIZE 16384
|
||||
|
||||
const static struct ssh_kex *kex_algs[] = {
|
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&ssh_diffiehellman_gex,
|
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&ssh_diffiehellman_group14,
|
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&ssh_diffiehellman_group1,
|
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};
|
||||
|
||||
const static struct ssh_signkey *hostkey_algs[] = { &ssh_rsa, &ssh_dss };
|
||||
|
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static void *nullmac_make_context(void)
|
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|
|
@ -2058,14 +2052,6 @@ static void ssh_detect_bugs(Ssh ssh, char *vstring)
|
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ssh->remote_bugs |= BUG_SSH2_PK_SESSIONID;
|
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logevent("We believe remote version has SSH2 public-key-session-ID bug");
|
||||
}
|
||||
|
||||
if (ssh->cfg.sshbug_dhgex2 == FORCE_ON) {
|
||||
/*
|
||||
* User specified the SSH2 DH GEX bug.
|
||||
*/
|
||||
ssh->remote_bugs |= BUG_SSH2_DH_GEX;
|
||||
logevent("We believe remote version has SSH2 DH group exchange bug");
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
|
|
@ -2761,7 +2747,7 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen,
|
|||
|
||||
/* Warn about chosen cipher if necessary. */
|
||||
if (warn)
|
||||
askcipher(ssh->frontend, cipher_string, 0);
|
||||
askalg(ssh->frontend, "cipher", cipher_string);
|
||||
}
|
||||
|
||||
switch (s->cipher_type) {
|
||||
|
|
@ -4321,6 +4307,8 @@ static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen,
|
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int hostkeylen, siglen;
|
||||
void *hkey; /* actual host key */
|
||||
unsigned char exchange_hash[20];
|
||||
int n_preferred_kex;
|
||||
const struct ssh_kex *preferred_kex[KEX_MAX];
|
||||
int n_preferred_ciphers;
|
||||
const struct ssh2_ciphers *preferred_ciphers[CIPHER_MAX];
|
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const struct ssh_compress *preferred_comp;
|
||||
|
|
@ -4337,6 +4325,37 @@ static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen,
|
|||
|
||||
s->first_kex = 1;
|
||||
|
||||
{
|
||||
int i;
|
||||
/*
|
||||
* Set up the preferred key exchange. (NULL => warn below here)
|
||||
*/
|
||||
s->n_preferred_kex = 0;
|
||||
for (i = 0; i < KEX_MAX; i++) {
|
||||
switch (ssh->cfg.ssh_kexlist[i]) {
|
||||
case KEX_DHGEX:
|
||||
s->preferred_kex[s->n_preferred_kex++] =
|
||||
&ssh_diffiehellman_gex;
|
||||
break;
|
||||
case KEX_DHGROUP14:
|
||||
s->preferred_kex[s->n_preferred_kex++] =
|
||||
&ssh_diffiehellman_group14;
|
||||
break;
|
||||
case KEX_DHGROUP1:
|
||||
s->preferred_kex[s->n_preferred_kex++] =
|
||||
&ssh_diffiehellman_group1;
|
||||
break;
|
||||
case CIPHER_WARN:
|
||||
/* Flag for later. Don't bother if it's the last in
|
||||
* the list. */
|
||||
if (i < KEX_MAX - 1) {
|
||||
s->preferred_kex[s->n_preferred_kex++] = NULL;
|
||||
}
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
{
|
||||
int i;
|
||||
/*
|
||||
|
|
@ -4388,7 +4407,7 @@ static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen,
|
|||
|
||||
begin_key_exchange:
|
||||
{
|
||||
int i, j, cipherstr_started;
|
||||
int i, j, commalist_started;
|
||||
|
||||
/*
|
||||
* Enable queueing of outgoing auth- or connection-layer
|
||||
|
|
@ -4409,13 +4428,14 @@ static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen,
|
|||
ssh2_pkt_addbyte(s->pktout, (unsigned char) random_byte());
|
||||
/* List key exchange algorithms. */
|
||||
ssh2_pkt_addstring_start(s->pktout);
|
||||
for (i = 0; i < lenof(kex_algs); i++) {
|
||||
if (kex_algs[i] == &ssh_diffiehellman_gex &&
|
||||
(ssh->remote_bugs & BUG_SSH2_DH_GEX))
|
||||
continue;
|
||||
ssh2_pkt_addstring_str(s->pktout, kex_algs[i]->name);
|
||||
if (i < lenof(kex_algs) - 1)
|
||||
commalist_started = 0;
|
||||
for (i = 0; i < s->n_preferred_kex; i++) {
|
||||
const struct ssh_kex *k = s->preferred_kex[i];
|
||||
if (!k) continue; /* warning flag */
|
||||
if (commalist_started)
|
||||
ssh2_pkt_addstring_str(s->pktout, ",");
|
||||
ssh2_pkt_addstring_str(s->pktout, s->preferred_kex[i]->name);
|
||||
commalist_started = 1;
|
||||
}
|
||||
/* List server host key algorithms. */
|
||||
ssh2_pkt_addstring_start(s->pktout);
|
||||
|
|
@ -4426,28 +4446,28 @@ static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen,
|
|||
}
|
||||
/* List client->server encryption algorithms. */
|
||||
ssh2_pkt_addstring_start(s->pktout);
|
||||
cipherstr_started = 0;
|
||||
commalist_started = 0;
|
||||
for (i = 0; i < s->n_preferred_ciphers; i++) {
|
||||
const struct ssh2_ciphers *c = s->preferred_ciphers[i];
|
||||
if (!c) continue; /* warning flag */
|
||||
for (j = 0; j < c->nciphers; j++) {
|
||||
if (cipherstr_started)
|
||||
if (commalist_started)
|
||||
ssh2_pkt_addstring_str(s->pktout, ",");
|
||||
ssh2_pkt_addstring_str(s->pktout, c->list[j]->name);
|
||||
cipherstr_started = 1;
|
||||
commalist_started = 1;
|
||||
}
|
||||
}
|
||||
/* List server->client encryption algorithms. */
|
||||
ssh2_pkt_addstring_start(s->pktout);
|
||||
cipherstr_started = 0;
|
||||
commalist_started = 0;
|
||||
for (i = 0; i < s->n_preferred_ciphers; i++) {
|
||||
const struct ssh2_ciphers *c = s->preferred_ciphers[i];
|
||||
if (!c) continue; /* warning flag */
|
||||
for (j = 0; j < c->nciphers; j++) {
|
||||
if (cipherstr_started)
|
||||
if (commalist_started)
|
||||
ssh2_pkt_addstring_str(s->pktout, ",");
|
||||
ssh2_pkt_addstring_str(s->pktout, c->list[j]->name);
|
||||
cipherstr_started = 1;
|
||||
commalist_started = 1;
|
||||
}
|
||||
}
|
||||
/* List client->server MAC algorithms. */
|
||||
|
|
@ -4528,15 +4548,26 @@ static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen,
|
|||
s->sccomp_tobe = NULL;
|
||||
pktin->savedpos += 16; /* skip garbage cookie */
|
||||
ssh_pkt_getstring(pktin, &str, &len); /* key exchange algorithms */
|
||||
for (i = 0; i < lenof(kex_algs); i++) {
|
||||
if (kex_algs[i] == &ssh_diffiehellman_gex &&
|
||||
(ssh->remote_bugs & BUG_SSH2_DH_GEX))
|
||||
continue;
|
||||
if (in_commasep_string(kex_algs[i]->name, str, len)) {
|
||||
ssh->kex = kex_algs[i];
|
||||
s->warn = 0;
|
||||
for (i = 0; i < s->n_preferred_kex; i++) {
|
||||
const struct ssh_kex *k = s->preferred_kex[i];
|
||||
if (!k) {
|
||||
s->warn = 1;
|
||||
} else if (in_commasep_string(k->name, str, len)) {
|
||||
ssh->kex = k;
|
||||
}
|
||||
if (ssh->kex) {
|
||||
if (s->warn)
|
||||
askalg(ssh->frontend, "key-exchange algorithm",
|
||||
ssh->kex->name);
|
||||
break;
|
||||
}
|
||||
}
|
||||
if (!ssh->kex) {
|
||||
bombout(("Couldn't agree a key exchange algorithm (available: %s)",
|
||||
str ? str : "(null)"));
|
||||
crStop(0);
|
||||
}
|
||||
ssh_pkt_getstring(pktin, &str, &len); /* host key algorithms */
|
||||
for (i = 0; i < lenof(hostkey_algs); i++) {
|
||||
if (in_commasep_string(hostkey_algs[i]->name, str, len)) {
|
||||
|
|
@ -4560,7 +4591,8 @@ static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen,
|
|||
}
|
||||
if (s->cscipher_tobe) {
|
||||
if (s->warn)
|
||||
askcipher(ssh->frontend, s->cscipher_tobe->name, 1);
|
||||
askalg(ssh->frontend, "client-to-server cipher",
|
||||
s->cscipher_tobe->name);
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
|
@ -4586,7 +4618,8 @@ static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen,
|
|||
}
|
||||
if (s->sccipher_tobe) {
|
||||
if (s->warn)
|
||||
askcipher(ssh->frontend, s->sccipher_tobe->name, 2);
|
||||
askalg(ssh->frontend, "server-to-client cipher",
|
||||
s->sccipher_tobe->name);
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
|
|
|||
|
|
@ -2351,22 +2351,19 @@ void verify_ssh_host_key(void *frontend, char *host, int port, char *keytype,
|
|||
}
|
||||
|
||||
/*
|
||||
* Ask whether the selected cipher is acceptable (since it was
|
||||
* Ask whether the selected algorithm is acceptable (since it was
|
||||
* below the configured 'warn' threshold).
|
||||
* cs: 0 = both ways, 1 = client->server, 2 = server->client
|
||||
*/
|
||||
void askcipher(void *frontend, char *ciphername, int cs)
|
||||
void askalg(void *frontend, const char *algtype, const char *algname)
|
||||
{
|
||||
static const char msg[] =
|
||||
"The first %scipher supported by the server is "
|
||||
"The first %s supported by the server is "
|
||||
"%s, which is below the configured warning threshold.\n"
|
||||
"Continue with connection?";
|
||||
char *text;
|
||||
int ret;
|
||||
|
||||
text = dupprintf(msg, (cs == 0) ? "" :
|
||||
(cs == 1) ? "client-to-server " : "server-to-client ",
|
||||
ciphername);
|
||||
text = dupprintf(msg, algtype, algname);
|
||||
ret = messagebox(GTK_WIDGET(get_window(frontend)),
|
||||
"PuTTY Security Alert", text,
|
||||
string_width("Continue with connection?"),
|
||||
|
|
|
|||
|
|
@ -143,18 +143,17 @@ void verify_ssh_host_key(void *frontend, char *host, int port, char *keytype,
|
|||
}
|
||||
|
||||
/*
|
||||
* Ask whether the selected cipher is acceptable (since it was
|
||||
* Ask whether the selected algorithm is acceptable (since it was
|
||||
* below the configured 'warn' threshold).
|
||||
* cs: 0 = both ways, 1 = client->server, 2 = server->client
|
||||
*/
|
||||
void askcipher(void *frontend, char *ciphername, int cs)
|
||||
void askalg(void *frontend, const char *algtype, const char *algname)
|
||||
{
|
||||
static const char msg[] =
|
||||
"The first %scipher supported by the server is\n"
|
||||
"The first %s supported by the server is\n"
|
||||
"%s, which is below the configured warning threshold.\n"
|
||||
"Continue with connection? (y/n) ";
|
||||
static const char msg_batch[] =
|
||||
"The first %scipher supported by the server is\n"
|
||||
"The first %s supported by the server is\n"
|
||||
"%s, which is below the configured warning threshold.\n"
|
||||
"Connection abandoned.\n";
|
||||
static const char abandoned[] = "Connection abandoned.\n";
|
||||
|
|
@ -162,17 +161,11 @@ void askcipher(void *frontend, char *ciphername, int cs)
|
|||
char line[32];
|
||||
|
||||
if (console_batch_mode) {
|
||||
fprintf(stderr, msg_batch,
|
||||
(cs == 0) ? "" :
|
||||
(cs == 1) ? "client-to-server " : "server-to-client ",
|
||||
ciphername);
|
||||
fprintf(stderr, msg_batch, algtype, algname);
|
||||
cleanup_exit(1);
|
||||
}
|
||||
|
||||
fprintf(stderr, msg,
|
||||
(cs == 0) ? "" :
|
||||
(cs == 1) ? "client-to-server " : "server-to-client ",
|
||||
ciphername);
|
||||
fprintf(stderr, msg, algtype, algname);
|
||||
fflush(stderr);
|
||||
|
||||
{
|
||||
|
|
|
|||
|
|
@ -147,21 +147,20 @@ void update_specials_menu(void *frontend)
|
|||
}
|
||||
|
||||
/*
|
||||
* Ask whether the selected cipher is acceptable (since it was
|
||||
* Ask whether the selected algorithm is acceptable (since it was
|
||||
* below the configured 'warn' threshold).
|
||||
* cs: 0 = both ways, 1 = client->server, 2 = server->client
|
||||
*/
|
||||
void askcipher(void *frontend, char *ciphername, int cs)
|
||||
void askalg(void *frontend, const char *algtype, const char *algname)
|
||||
{
|
||||
HANDLE hin;
|
||||
DWORD savemode, i;
|
||||
|
||||
static const char msg[] =
|
||||
"The first %scipher supported by the server is\n"
|
||||
"The first %s supported by the server is\n"
|
||||
"%s, which is below the configured warning threshold.\n"
|
||||
"Continue with connection? (y/n) ";
|
||||
static const char msg_batch[] =
|
||||
"The first %scipher supported by the server is\n"
|
||||
"The first %s supported by the server is\n"
|
||||
"%s, which is below the configured warning threshold.\n"
|
||||
"Connection abandoned.\n";
|
||||
static const char abandoned[] = "Connection abandoned.\n";
|
||||
|
|
@ -169,17 +168,11 @@ void askcipher(void *frontend, char *ciphername, int cs)
|
|||
char line[32];
|
||||
|
||||
if (console_batch_mode) {
|
||||
fprintf(stderr, msg_batch,
|
||||
(cs == 0) ? "" :
|
||||
(cs == 1) ? "client-to-server " : "server-to-client ",
|
||||
ciphername);
|
||||
fprintf(stderr, msg_batch, algtype, algname);
|
||||
cleanup_exit(1);
|
||||
}
|
||||
|
||||
fprintf(stderr, msg,
|
||||
(cs == 0) ? "" :
|
||||
(cs == 1) ? "client-to-server " : "server-to-client ",
|
||||
ciphername);
|
||||
fprintf(stderr, msg, algtype, algname);
|
||||
fflush(stderr);
|
||||
|
||||
hin = GetStdHandle(STD_INPUT_HANDLE);
|
||||
|
|
|
|||
|
|
@ -777,24 +777,21 @@ void verify_ssh_host_key(void *frontend, char *host, int port, char *keytype,
|
|||
}
|
||||
|
||||
/*
|
||||
* Ask whether the selected cipher is acceptable (since it was
|
||||
* Ask whether the selected algorithm is acceptable (since it was
|
||||
* below the configured 'warn' threshold).
|
||||
* cs: 0 = both ways, 1 = client->server, 2 = server->client
|
||||
*/
|
||||
void askcipher(void *frontend, char *ciphername, int cs)
|
||||
void askalg(void *frontend, const char *algtype, const char *algname)
|
||||
{
|
||||
static const char mbtitle[] = "%s Security Alert";
|
||||
static const char msg[] =
|
||||
"The first %.35scipher supported by the server\n"
|
||||
"The first %s supported by the server\n"
|
||||
"is %.64s, which is below the configured\n"
|
||||
"warning threshold.\n"
|
||||
"Do you want to continue with this connection?\n";
|
||||
char *message, *title;
|
||||
int mbret;
|
||||
|
||||
message = dupprintf(msg, ((cs == 0) ? "" :
|
||||
(cs == 1) ? "client-to-server " :
|
||||
"server-to-client "), ciphername);
|
||||
message = dupprintf(msg, algtype, algname);
|
||||
title = dupprintf(mbtitle, appname);
|
||||
mbret = MessageBox(NULL, message, title,
|
||||
MB_ICONWARNING | MB_YESNO);
|
||||
|
|
|
|||
|
|
@ -86,6 +86,7 @@
|
|||
#define WINHELP_CTX_ssh_protocol "ssh.protocol"
|
||||
#define WINHELP_CTX_ssh_command "ssh.command"
|
||||
#define WINHELP_CTX_ssh_compress "ssh.compress"
|
||||
#define WINHELP_CTX_ssh_kexlist "ssh.kex.order"
|
||||
#define WINHELP_CTX_ssh_auth_privkey "ssh.auth.privkey"
|
||||
#define WINHELP_CTX_ssh_auth_agentfwd "ssh.auth.agentfwd"
|
||||
#define WINHELP_CTX_ssh_auth_changeuser "ssh.auth.changeuser"
|
||||
|
|
@ -116,5 +117,4 @@
|
|||
#define WINHELP_CTX_ssh_bugs_hmac2 "ssh.bugs.hmac2"
|
||||
#define WINHELP_CTX_ssh_bugs_derivekey2 "ssh.bugs.derivekey2"
|
||||
#define WINHELP_CTX_ssh_bugs_rsapad2 "ssh.bugs.rsapad2"
|
||||
#define WINHELP_CTX_ssh_bugs_dhgex2 "ssh.bugs.dhgex2"
|
||||
#define WINHELP_CTX_ssh_bugs_pksessid2 "ssh.bugs.pksessid2"
|
||||
|
|
|
|||
Загрузка…
Ссылка в новой задаче