mirror of
https://git.tartarus.org/simon/putty.git
synced 2025-07-05 21:42:47 -05:00
Move version string exchange out into a BPP.
Getting it out of the overgrown ssh.c is worthwhile in itself! But there are other benefits of this reorganisation too. One is that I get to remove ssh->current_incoming_data_fn, because now _all_ incoming network data is handled by whatever the current BPP is. So now we only indirect through the BPP, not through some other preliminary function pointer _and_ the BPP. Another is that all _outgoing_ network data is now handled centrally, including our outgoing version string - which means that a hex dump of that string now shows up in the raw-data log file, from which it was previously conspicuous by its absence.
This commit is contained in:
Simon Tatham
660
ssh.c
660
ssh.c
@ -661,6 +661,7 @@ enum RekeyClass {
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struct ssh_tag {
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char *v_c, *v_s;
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struct ssh_version_receiver version_receiver;
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ssh_hash *exhash;
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Socket s;
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@ -795,7 +796,6 @@ struct ssh_tag {
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BinaryPacketProtocol *bpp;
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void (*general_packet_processing)(Ssh ssh, PktIn *pkt);
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void (*current_incoming_data_fn) (Ssh ssh);
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void (*current_user_input_fn) (Ssh ssh);
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/*
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@ -1149,26 +1149,6 @@ static void ssh_pkt_write(Ssh ssh, PktOut *pkt)
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queue_idempotent_callback(&ssh->outgoing_data_sender);
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}
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static int ssh_versioncmp(const char *a, const char *b)
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{
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char *ae, *be;
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unsigned long av, bv;
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av = strtoul(a, &ae, 10);
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bv = strtoul(b, &be, 10);
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if (av != bv)
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return (av < bv ? -1 : +1);
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if (*ae == '.')
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ae++;
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if (*be == '.')
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be++;
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av = strtoul(ae, &ae, 10);
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bv = strtoul(be, &be, 10);
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if (av != bv)
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return (av < bv ? -1 : +1);
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return 0;
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}
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/*
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* Packet construction functions. Mostly shared between SSH-1 and SSH-2.
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*/
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@ -1346,258 +1326,6 @@ static void ssh2_add_sigblob(Ssh ssh, PktOut *pkt,
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put_string(pkt, sigblob, sigblob_len);
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}
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/*
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* Examine the remote side's version string and compare it against
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* a list of known buggy implementations.
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*/
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static void ssh_detect_bugs(Ssh ssh, char *vstring)
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{
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char *imp; /* pointer to implementation part */
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imp = vstring;
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imp += strcspn(imp, "-");
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if (*imp) imp++;
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imp += strcspn(imp, "-");
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if (*imp) imp++;
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ssh->remote_bugs = 0;
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/*
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* General notes on server version strings:
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* - Not all servers reporting "Cisco-1.25" have all the bugs listed
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* here -- in particular, we've heard of one that's perfectly happy
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* with SSH1_MSG_IGNOREs -- but this string never seems to change,
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* so we can't distinguish them.
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*/
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if (conf_get_int(ssh->conf, CONF_sshbug_ignore1) == FORCE_ON ||
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(conf_get_int(ssh->conf, CONF_sshbug_ignore1) == AUTO &&
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(!strcmp(imp, "1.2.18") || !strcmp(imp, "1.2.19") ||
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!strcmp(imp, "1.2.20") || !strcmp(imp, "1.2.21") ||
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!strcmp(imp, "1.2.22") || !strcmp(imp, "Cisco-1.25") ||
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!strcmp(imp, "OSU_1.4alpha3") || !strcmp(imp, "OSU_1.5alpha4")))) {
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/*
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* These versions don't support SSH1_MSG_IGNORE, so we have
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* to use a different defence against password length
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* sniffing.
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*/
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ssh->remote_bugs |= BUG_CHOKES_ON_SSH1_IGNORE;
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logevent("We believe remote version has SSH-1 ignore bug");
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}
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if (conf_get_int(ssh->conf, CONF_sshbug_plainpw1) == FORCE_ON ||
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(conf_get_int(ssh->conf, CONF_sshbug_plainpw1) == AUTO &&
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(!strcmp(imp, "Cisco-1.25") || !strcmp(imp, "OSU_1.4alpha3")))) {
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/*
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* These versions need a plain password sent; they can't
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* handle having a null and a random length of data after
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* the password.
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*/
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ssh->remote_bugs |= BUG_NEEDS_SSH1_PLAIN_PASSWORD;
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logevent("We believe remote version needs a plain SSH-1 password");
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}
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if (conf_get_int(ssh->conf, CONF_sshbug_rsa1) == FORCE_ON ||
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(conf_get_int(ssh->conf, CONF_sshbug_rsa1) == AUTO &&
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(!strcmp(imp, "Cisco-1.25")))) {
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/*
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* These versions apparently have no clue whatever about
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* RSA authentication and will panic and die if they see
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* an AUTH_RSA message.
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*/
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ssh->remote_bugs |= BUG_CHOKES_ON_RSA;
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logevent("We believe remote version can't handle SSH-1 RSA authentication");
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}
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if (conf_get_int(ssh->conf, CONF_sshbug_hmac2) == FORCE_ON ||
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(conf_get_int(ssh->conf, CONF_sshbug_hmac2) == AUTO &&
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!wc_match("* VShell", imp) &&
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(wc_match("2.1.0*", imp) || wc_match("2.0.*", imp) ||
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wc_match("2.2.0*", imp) || wc_match("2.3.0*", imp) ||
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wc_match("2.1 *", imp)))) {
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/*
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* These versions have the HMAC bug.
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*/
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ssh->remote_bugs |= BUG_SSH2_HMAC;
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logevent("We believe remote version has SSH-2 HMAC bug");
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}
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if (conf_get_int(ssh->conf, CONF_sshbug_derivekey2) == FORCE_ON ||
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(conf_get_int(ssh->conf, CONF_sshbug_derivekey2) == AUTO &&
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!wc_match("* VShell", imp) &&
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(wc_match("2.0.0*", imp) || wc_match("2.0.10*", imp) ))) {
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/*
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* These versions have the key-derivation bug (failing to
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* include the literal shared secret in the hashes that
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* generate the keys).
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*/
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ssh->remote_bugs |= BUG_SSH2_DERIVEKEY;
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logevent("We believe remote version has SSH-2 key-derivation bug");
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}
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if (conf_get_int(ssh->conf, CONF_sshbug_rsapad2) == FORCE_ON ||
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(conf_get_int(ssh->conf, CONF_sshbug_rsapad2) == AUTO &&
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(wc_match("OpenSSH_2.[5-9]*", imp) ||
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wc_match("OpenSSH_3.[0-2]*", imp) ||
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wc_match("mod_sftp/0.[0-8]*", imp) ||
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wc_match("mod_sftp/0.9.[0-8]", imp)))) {
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/*
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* These versions have the SSH-2 RSA padding bug.
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*/
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ssh->remote_bugs |= BUG_SSH2_RSA_PADDING;
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logevent("We believe remote version has SSH-2 RSA padding bug");
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}
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if (conf_get_int(ssh->conf, CONF_sshbug_pksessid2) == FORCE_ON ||
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(conf_get_int(ssh->conf, CONF_sshbug_pksessid2) == AUTO &&
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wc_match("OpenSSH_2.[0-2]*", imp))) {
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/*
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* These versions have the SSH-2 session-ID bug in
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* public-key authentication.
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*/
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ssh->remote_bugs |= BUG_SSH2_PK_SESSIONID;
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logevent("We believe remote version has SSH-2 public-key-session-ID bug");
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}
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if (conf_get_int(ssh->conf, CONF_sshbug_rekey2) == FORCE_ON ||
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(conf_get_int(ssh->conf, CONF_sshbug_rekey2) == AUTO &&
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(wc_match("DigiSSH_2.0", imp) ||
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wc_match("OpenSSH_2.[0-4]*", imp) ||
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wc_match("OpenSSH_2.5.[0-3]*", imp) ||
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wc_match("Sun_SSH_1.0", imp) ||
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wc_match("Sun_SSH_1.0.1", imp) ||
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/* All versions <= 1.2.6 (they changed their format in 1.2.7) */
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wc_match("WeOnlyDo-*", imp)))) {
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/*
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* These versions have the SSH-2 rekey bug.
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*/
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ssh->remote_bugs |= BUG_SSH2_REKEY;
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logevent("We believe remote version has SSH-2 rekey bug");
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}
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if (conf_get_int(ssh->conf, CONF_sshbug_maxpkt2) == FORCE_ON ||
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(conf_get_int(ssh->conf, CONF_sshbug_maxpkt2) == AUTO &&
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(wc_match("1.36_sshlib GlobalSCAPE", imp) ||
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wc_match("1.36 sshlib: GlobalScape", imp)))) {
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/*
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* This version ignores our makpkt and needs to be throttled.
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*/
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ssh->remote_bugs |= BUG_SSH2_MAXPKT;
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logevent("We believe remote version ignores SSH-2 maximum packet size");
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}
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if (conf_get_int(ssh->conf, CONF_sshbug_ignore2) == FORCE_ON) {
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/*
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* Servers that don't support SSH2_MSG_IGNORE. Currently,
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* none detected automatically.
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*/
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ssh->remote_bugs |= BUG_CHOKES_ON_SSH2_IGNORE;
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logevent("We believe remote version has SSH-2 ignore bug");
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}
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if (conf_get_int(ssh->conf, CONF_sshbug_oldgex2) == FORCE_ON ||
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(conf_get_int(ssh->conf, CONF_sshbug_oldgex2) == AUTO &&
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(wc_match("OpenSSH_2.[235]*", imp)))) {
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/*
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* These versions only support the original (pre-RFC4419)
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* SSH-2 GEX request, and disconnect with a protocol error if
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* we use the newer version.
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*/
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ssh->remote_bugs |= BUG_SSH2_OLDGEX;
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logevent("We believe remote version has outdated SSH-2 GEX");
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}
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if (conf_get_int(ssh->conf, CONF_sshbug_winadj) == FORCE_ON) {
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/*
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* Servers that don't support our winadj request for one
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* reason or another. Currently, none detected automatically.
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*/
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ssh->remote_bugs |= BUG_CHOKES_ON_WINADJ;
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logevent("We believe remote version has winadj bug");
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}
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if (conf_get_int(ssh->conf, CONF_sshbug_chanreq) == FORCE_ON ||
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(conf_get_int(ssh->conf, CONF_sshbug_chanreq) == AUTO &&
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(wc_match("OpenSSH_[2-5].*", imp) ||
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wc_match("OpenSSH_6.[0-6]*", imp) ||
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wc_match("dropbear_0.[2-4][0-9]*", imp) ||
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wc_match("dropbear_0.5[01]*", imp)))) {
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/*
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* These versions have the SSH-2 channel request bug.
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* OpenSSH 6.7 and above do not:
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* https://bugzilla.mindrot.org/show_bug.cgi?id=1818
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* dropbear_0.52 and above do not:
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* https://secure.ucc.asn.au/hg/dropbear/rev/cd02449b709c
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*/
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ssh->remote_bugs |= BUG_SENDS_LATE_REQUEST_REPLY;
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logevent("We believe remote version has SSH-2 channel request bug");
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}
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}
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/*
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* The `software version' part of an SSH version string is required
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* to contain no spaces or minus signs.
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*/
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static void ssh_fix_verstring(char *str)
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{
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/* Eat "<protoversion>-". */
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while (*str && *str != '-') str++;
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assert(*str == '-'); str++;
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/* Convert minus signs and spaces in the remaining string into
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* underscores. */
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while (*str) {
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if (*str == '-' || *str == ' ')
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*str = '_';
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str++;
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}
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}
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/*
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* Send an appropriate SSH version string.
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*/
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static void ssh_send_verstring(Ssh ssh, const char *protoname, char *svers)
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{
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char *verstring;
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if (ssh->version == 2) {
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/*
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* Construct a v2 version string.
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*/
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verstring = dupprintf("%s2.0-%s\015\012", protoname, sshver);
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} else {
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/*
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* Construct a v1 version string.
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*/
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assert(!strcmp(protoname, "SSH-")); /* no v1 bare connection protocol */
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verstring = dupprintf("SSH-%s-%s\012",
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(ssh_versioncmp(svers, "1.5") <= 0 ?
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svers : "1.5"),
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sshver);
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}
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ssh_fix_verstring(verstring + strlen(protoname));
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#ifdef FUZZING
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/* FUZZING make PuTTY insecure, so make live use difficult. */
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verstring[0] = 'I';
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#endif
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if (ssh->version == 2) {
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size_t len;
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/*
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* Record our version string.
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*/
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len = strcspn(verstring, "\015\012");
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ssh->v_c = snewn(len + 1, char);
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memcpy(ssh->v_c, verstring, len);
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ssh->v_c[len] = 0;
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}
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logeventf(ssh, "We claim version: %.*s",
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strcspn(verstring, "\015\012"), verstring);
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bufchain_add(&ssh->outgoing_data, verstring, strlen(verstring));
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queue_idempotent_callback(&ssh->outgoing_data_sender);
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sfree(verstring);
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}
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static void ssh_feed_to_bpp(Ssh ssh)
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{
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PacketQueueNode *prev_tail = ssh->pq_full.end.prev;
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@ -1628,342 +1356,83 @@ static void ssh_feed_to_bpp(Ssh ssh)
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queue_idempotent_callback(&ssh->pq_full_consumer);
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}
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static void do_ssh_init(Ssh ssh)
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static void ssh_got_ssh_version(struct ssh_version_receiver *rcv,
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int major_version)
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{
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static const char protoname[] = "SSH-";
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struct do_ssh_init_state {
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int crLine;
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int vslen;
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char *vstring;
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char *version;
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int vstrsize;
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int i;
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int proto1, proto2;
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};
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crState(do_ssh_init_state);
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crBeginState;
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Ssh ssh = FROMFIELD(rcv, struct ssh_tag, version_receiver);
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BinaryPacketProtocol *old_bpp;
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/*
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* Search for a line beginning with the protocol name prefix in
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* the input.
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* Queue an outgoing-data run: if the version string has been sent
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* late rather than early, it'll still be sitting on our output
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* raw data queue.
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*/
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s->i = 0;
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while (1) {
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char prefix[sizeof(protoname)-1];
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/*
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* Every time round this loop, we're at the start of a new
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* line, so look for the prefix.
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*/
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crMaybeWaitUntilV(
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bufchain_size(&ssh->incoming_data) >= sizeof(prefix));
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bufchain_fetch(&ssh->incoming_data, prefix, sizeof(prefix));
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if (!memcmp(prefix, protoname, sizeof(prefix))) {
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bufchain_consume(&ssh->incoming_data, sizeof(prefix));
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break;
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}
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/*
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* If we didn't find it, consume data until we see a newline.
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*/
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while (1) {
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int len;
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void *data;
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char *nl;
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crMaybeWaitUntilV(bufchain_size(&ssh->incoming_data) > 0);
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bufchain_prefix(&ssh->incoming_data, &data, &len);
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if ((nl = memchr(data, '\012', len)) != NULL) {
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bufchain_consume(&ssh->incoming_data, nl - (char *)data + 1);
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break;
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} else {
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bufchain_consume(&ssh->incoming_data, len);
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}
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}
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}
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ssh->session_started = TRUE;
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ssh->agentfwd_enabled = FALSE;
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queue_idempotent_callback(&ssh->outgoing_data_sender);
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/*
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* Now read the rest of the greeting line.
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* We don't support choosing a major protocol version dynamically,
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* so this should always be the same value we set up in
|
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* connect_to_host().
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*/
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s->vstrsize = sizeof(protoname) + 16;
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s->vstring = snewn(s->vstrsize, char);
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strcpy(s->vstring, protoname);
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s->vslen = strlen(protoname);
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s->i = 0;
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do {
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int len;
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void *data;
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char *nl;
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assert(ssh->version == major_version);
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crMaybeWaitUntilV(bufchain_size(&ssh->incoming_data) > 0);
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bufchain_prefix(&ssh->incoming_data, &data, &len);
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if ((nl = memchr(data, '\012', len)) != NULL) {
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len = nl - (char *)data + 1;
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old_bpp = ssh->bpp;
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ssh->remote_bugs = ssh_verstring_get_bugs(old_bpp);
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if (!ssh->bare_connection) {
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if (ssh->version == 2) {
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/*
|
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* Retrieve both version strings from the old BPP before
|
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* we free it.
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*/
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ssh->v_s = dupstr(ssh_verstring_get_remote(old_bpp));
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ssh->v_c = dupstr(ssh_verstring_get_local(old_bpp));
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/*
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* Initialise SSH-2 protocol.
|
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*/
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ssh2_protocol_setup(ssh);
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ssh->general_packet_processing = ssh2_general_packet_processing;
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ssh->current_user_input_fn = NULL;
|
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} else {
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/*
|
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* Initialise SSH-1 protocol.
|
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*/
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ssh1_protocol_setup(ssh);
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ssh->current_user_input_fn = ssh1_login_input;
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}
|
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if (s->vslen + len >= s->vstrsize - 1) {
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s->vstrsize = (s->vslen + len) * 5 / 4 + 32;
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s->vstring = sresize(s->vstring, s->vstrsize, char);
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}
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if (ssh->version == 2)
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queue_idempotent_callback(&ssh->ssh2_transport_icb);
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|
||||
memcpy(s->vstring + s->vslen, data, len);
|
||||
s->vslen += len;
|
||||
bufchain_consume(&ssh->incoming_data, len);
|
||||
|
||||
} while (s->vstring[s->vslen-1] != '\012');
|
||||
|
||||
s->vstring[s->vslen] = 0;
|
||||
s->vstring[strcspn(s->vstring, "\015\012")] = '\0';/* remove EOL chars */
|
||||
|
||||
logeventf(ssh, "Server version: %s", s->vstring);
|
||||
ssh_detect_bugs(ssh, s->vstring);
|
||||
|
||||
/*
|
||||
* Decide which SSH protocol version to support.
|
||||
*/
|
||||
s->version = dupprintf(
|
||||
"%.*s", (int)strcspn(s->vstring + strlen(protoname), "-"),
|
||||
s->vstring + strlen(protoname));
|
||||
|
||||
/* Anything strictly below "2.0" means protocol 1 is supported. */
|
||||
s->proto1 = ssh_versioncmp(s->version, "2.0") < 0;
|
||||
/* Anything greater or equal to "1.99" means protocol 2 is supported. */
|
||||
s->proto2 = ssh_versioncmp(s->version, "1.99") >= 0;
|
||||
|
||||
if (conf_get_int(ssh->conf, CONF_sshprot) == 0) {
|
||||
if (!s->proto1) {
|
||||
bombout(("SSH protocol version 1 required by our configuration "
|
||||
"but not provided by server"));
|
||||
crStopV;
|
||||
}
|
||||
} else if (conf_get_int(ssh->conf, CONF_sshprot) == 3) {
|
||||
if (!s->proto2) {
|
||||
bombout(("SSH protocol version 2 required by our configuration "
|
||||
"but server only provides (old, insecure) SSH-1"));
|
||||
crStopV;
|
||||
}
|
||||
} else {
|
||||
/* No longer support values 1 or 2 for CONF_sshprot */
|
||||
assert(!"Unexpected value for CONF_sshprot");
|
||||
assert(ssh->version == 2); /* can't do SSH-1 bare connection! */
|
||||
logeventf(ssh, "Using bare ssh-connection protocol");
|
||||
|
||||
ssh2_bare_connection_protocol_setup(ssh);
|
||||
ssh->current_user_input_fn = ssh2_connection_input;
|
||||
|
||||
}
|
||||
|
||||
if (s->proto2 && (conf_get_int(ssh->conf, CONF_sshprot) >= 2 || !s->proto1))
|
||||
ssh->version = 2;
|
||||
else
|
||||
ssh->version = 1;
|
||||
|
||||
logeventf(ssh, "Using SSH protocol version %d", ssh->version);
|
||||
|
||||
/* Send the version string, if we haven't already */
|
||||
if (conf_get_int(ssh->conf, CONF_sshprot) != 3)
|
||||
ssh_send_verstring(ssh, protoname, s->version);
|
||||
|
||||
sfree(s->version);
|
||||
|
||||
if (ssh->version == 2) {
|
||||
size_t len;
|
||||
/*
|
||||
* Record their version string.
|
||||
*/
|
||||
len = strcspn(s->vstring, "\015\012");
|
||||
ssh->v_s = snewn(len + 1, char);
|
||||
memcpy(ssh->v_s, s->vstring, len);
|
||||
ssh->v_s[len] = 0;
|
||||
|
||||
/*
|
||||
* Initialise SSH-2 protocol.
|
||||
*/
|
||||
ssh2_protocol_setup(ssh);
|
||||
ssh->general_packet_processing = ssh2_general_packet_processing;
|
||||
ssh->current_user_input_fn = NULL;
|
||||
} else {
|
||||
/*
|
||||
* Initialise SSH-1 protocol.
|
||||
*/
|
||||
ssh1_protocol_setup(ssh);
|
||||
ssh->current_user_input_fn = ssh1_login_input;
|
||||
}
|
||||
ssh->bpp->out_raw = &ssh->outgoing_data;
|
||||
ssh->bpp->in_raw = &ssh->incoming_data;
|
||||
ssh->bpp->in_pq = &ssh->pq_full;
|
||||
ssh->bpp->pls = &ssh->pls;
|
||||
ssh->bpp->logctx = ssh->logctx;
|
||||
ssh->current_incoming_data_fn = ssh_feed_to_bpp;
|
||||
|
||||
queue_idempotent_callback(&ssh->incoming_data_consumer);
|
||||
queue_idempotent_callback(&ssh->user_input_consumer);
|
||||
if (ssh->version == 2)
|
||||
queue_idempotent_callback(&ssh->ssh2_transport_icb);
|
||||
|
||||
update_specials_menu(ssh->frontend);
|
||||
ssh->state = SSH_STATE_BEFORE_SIZE;
|
||||
ssh->pinger = pinger_new(ssh->conf, &ssh->backend);
|
||||
|
||||
sfree(s->vstring);
|
||||
|
||||
crFinishV;
|
||||
}
|
||||
|
||||
static void do_ssh_connection_init(Ssh ssh)
|
||||
{
|
||||
/*
|
||||
* Ordinary SSH begins with the banner "SSH-x.y-...". This is just
|
||||
* the ssh-connection part, extracted and given a trivial binary
|
||||
* packet protocol, so we replace 'SSH-' at the start with a new
|
||||
* name. In proper SSH style (though of course this part of the
|
||||
* proper SSH protocol _isn't_ subject to this kind of
|
||||
* DNS-domain-based extension), we define the new name in our
|
||||
* extension space.
|
||||
*/
|
||||
static const char protoname[] =
|
||||
"SSHCONNECTION@putty.projects.tartarus.org-";
|
||||
|
||||
struct do_ssh_connection_init_state {
|
||||
int crLine;
|
||||
int vslen;
|
||||
char *vstring;
|
||||
char *version;
|
||||
int vstrsize;
|
||||
int i;
|
||||
};
|
||||
crState(do_ssh_connection_init_state);
|
||||
|
||||
crBeginState;
|
||||
|
||||
/*
|
||||
* Search for a line beginning with the protocol name prefix in
|
||||
* the input.
|
||||
*/
|
||||
s->i = 0;
|
||||
while (1) {
|
||||
char prefix[sizeof(protoname)-1];
|
||||
|
||||
/*
|
||||
* Every time round this loop, we're at the start of a new
|
||||
* line, so look for the prefix.
|
||||
*/
|
||||
crMaybeWaitUntilV(
|
||||
bufchain_size(&ssh->incoming_data) >= sizeof(prefix));
|
||||
bufchain_fetch(&ssh->incoming_data, prefix, sizeof(prefix));
|
||||
if (!memcmp(prefix, protoname, sizeof(prefix))) {
|
||||
bufchain_consume(&ssh->incoming_data, sizeof(prefix));
|
||||
break;
|
||||
}
|
||||
|
||||
/*
|
||||
* If we didn't find it, consume data until we see a newline.
|
||||
*/
|
||||
while (1) {
|
||||
int len;
|
||||
void *data;
|
||||
char *nl;
|
||||
|
||||
crMaybeWaitUntilV(bufchain_size(&ssh->incoming_data) > 0);
|
||||
bufchain_prefix(&ssh->incoming_data, &data, &len);
|
||||
if ((nl = memchr(data, '\012', len)) != NULL) {
|
||||
bufchain_consume(&ssh->incoming_data, nl - (char *)data + 1);
|
||||
break;
|
||||
} else {
|
||||
bufchain_consume(&ssh->incoming_data, len);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* Now read the rest of the greeting line.
|
||||
*/
|
||||
s->vstrsize = sizeof(protoname) + 16;
|
||||
s->vstring = snewn(s->vstrsize, char);
|
||||
strcpy(s->vstring, protoname);
|
||||
s->vslen = strlen(protoname);
|
||||
s->i = 0;
|
||||
do {
|
||||
int len;
|
||||
void *data;
|
||||
char *nl;
|
||||
|
||||
crMaybeWaitUntilV(bufchain_size(&ssh->incoming_data) > 0);
|
||||
bufchain_prefix(&ssh->incoming_data, &data, &len);
|
||||
if ((nl = memchr(data, '\012', len)) != NULL) {
|
||||
len = nl - (char *)data + 1;
|
||||
}
|
||||
|
||||
if (s->vslen + len >= s->vstrsize - 1) {
|
||||
s->vstrsize = (s->vslen + len) * 5 / 4 + 32;
|
||||
s->vstring = sresize(s->vstring, s->vstrsize, char);
|
||||
}
|
||||
|
||||
memcpy(s->vstring + s->vslen, data, len);
|
||||
s->vslen += len;
|
||||
bufchain_consume(&ssh->incoming_data, len);
|
||||
|
||||
} while (s->vstring[s->vslen-1] != '\012');
|
||||
|
||||
s->vstring[s->vslen] = 0;
|
||||
s->vstring[strcspn(s->vstring, "\015\012")] = '\0';/* remove EOL chars */
|
||||
|
||||
ssh->agentfwd_enabled = FALSE;
|
||||
|
||||
logeventf(ssh, "Server version: %s", s->vstring);
|
||||
ssh_detect_bugs(ssh, s->vstring);
|
||||
|
||||
/*
|
||||
* Decide which SSH protocol version to support. This is easy in
|
||||
* bare ssh-connection mode: only 2.0 is legal.
|
||||
*/
|
||||
s->version = dupprintf(
|
||||
"%.*s", (int)strcspn(s->vstring + strlen(protoname), "-"),
|
||||
s->vstring + strlen(protoname));
|
||||
|
||||
if (ssh_versioncmp(s->version, "2.0") < 0) {
|
||||
bombout(("Server announces compatibility with SSH-1 in bare ssh-connection protocol"));
|
||||
crStopV;
|
||||
}
|
||||
if (conf_get_int(ssh->conf, CONF_sshprot) == 0) {
|
||||
bombout(("Bare ssh-connection protocol cannot be run in SSH-1-only mode"));
|
||||
crStopV;
|
||||
}
|
||||
|
||||
ssh->version = 2;
|
||||
|
||||
logeventf(ssh, "Using bare ssh-connection protocol");
|
||||
|
||||
/* Send the version string, if we haven't already */
|
||||
ssh_send_verstring(ssh, protoname, s->version);
|
||||
|
||||
sfree(s->version);
|
||||
|
||||
/*
|
||||
* Initialise bare connection protocol.
|
||||
*/
|
||||
ssh2_bare_connection_protocol_setup(ssh);
|
||||
ssh->bpp->out_raw = &ssh->outgoing_data;
|
||||
ssh->bpp->in_raw = &ssh->incoming_data;
|
||||
ssh->bpp->in_pq = &ssh->pq_full;
|
||||
ssh->bpp->pls = &ssh->pls;
|
||||
ssh->bpp->logctx = ssh->logctx;
|
||||
ssh->current_incoming_data_fn = ssh_feed_to_bpp;
|
||||
queue_idempotent_callback(&ssh->incoming_data_consumer);
|
||||
ssh->current_user_input_fn = ssh2_connection_input;
|
||||
queue_idempotent_callback(&ssh->user_input_consumer);
|
||||
|
||||
update_specials_menu(ssh->frontend);
|
||||
ssh->state = SSH_STATE_BEFORE_SIZE;
|
||||
ssh->pinger = pinger_new(ssh->conf, &ssh->backend);
|
||||
|
||||
/*
|
||||
* Get connection protocol under way.
|
||||
*/
|
||||
do_ssh2_connection(ssh);
|
||||
|
||||
sfree(s->vstring);
|
||||
|
||||
crFinishV;
|
||||
if (ssh->bare_connection) {
|
||||
/*
|
||||
* Get connection protocol under way.
|
||||
*/
|
||||
do_ssh2_connection(ssh);
|
||||
}
|
||||
}
|
||||
|
||||
static void ssh_set_frozen(Ssh ssh, int frozen)
|
||||
@ -1981,7 +1450,7 @@ static void ssh_process_incoming_data(void *ctx)
|
||||
return;
|
||||
|
||||
if (!ssh->frozen)
|
||||
ssh->current_incoming_data_fn(ssh);
|
||||
ssh_feed_to_bpp(ssh);
|
||||
|
||||
if (ssh->state == SSH_STATE_CLOSED) /* yes, check _again_ */
|
||||
return;
|
||||
@ -2317,7 +1786,6 @@ static const char *connect_to_host(Ssh ssh, const char *host, int port,
|
||||
* We are a downstream.
|
||||
*/
|
||||
ssh->bare_connection = TRUE;
|
||||
ssh->current_incoming_data_fn = do_ssh_connection_init;
|
||||
ssh->fullhostname = NULL;
|
||||
*realhost = dupstr(host); /* best we can do */
|
||||
|
||||
@ -2332,7 +1800,6 @@ static const char *connect_to_host(Ssh ssh, const char *host, int port,
|
||||
/*
|
||||
* We're not a downstream, so open a normal socket.
|
||||
*/
|
||||
ssh->current_incoming_data_fn = do_ssh_init;
|
||||
|
||||
/*
|
||||
* Try to find host.
|
||||
@ -2358,20 +1825,35 @@ static const char *connect_to_host(Ssh ssh, const char *host, int port,
|
||||
|
||||
/*
|
||||
* The SSH version number is always fixed (since we no longer support
|
||||
* fallback between versions), so set it now, and if it's SSH-2,
|
||||
* send the version string now too.
|
||||
* fallback between versions), so set it now.
|
||||
*/
|
||||
sshprot = conf_get_int(ssh->conf, CONF_sshprot);
|
||||
assert(sshprot == 0 || sshprot == 3);
|
||||
if (sshprot == 0)
|
||||
/* SSH-1 only */
|
||||
ssh->version = 1;
|
||||
if (sshprot == 3 && !ssh->bare_connection) {
|
||||
if (sshprot == 3 || ssh->bare_connection) {
|
||||
/* SSH-2 only */
|
||||
ssh->version = 2;
|
||||
ssh_send_verstring(ssh, "SSH-", NULL);
|
||||
}
|
||||
|
||||
/*
|
||||
* Set up the initial BPP that will do the version string
|
||||
* exchange.
|
||||
*/
|
||||
ssh->version_receiver.got_ssh_version = ssh_got_ssh_version;
|
||||
ssh->bpp = ssh_verstring_new(
|
||||
ssh->conf, ssh->frontend, ssh->bare_connection,
|
||||
ssh->version == 1 ? "1.5" : "2.0", &ssh->version_receiver);
|
||||
ssh->bpp->out_raw = &ssh->outgoing_data;
|
||||
ssh->bpp->in_raw = &ssh->incoming_data;
|
||||
/*
|
||||
* And call its handle_input method right now, in case it wants to
|
||||
* send the outgoing version string immediately.
|
||||
*/
|
||||
ssh_bpp_handle_input(ssh->bpp);
|
||||
queue_idempotent_callback(&ssh->outgoing_data_sender);
|
||||
|
||||
/*
|
||||
* loghost, if configured, overrides realhost.
|
||||
*/
|
||||
|
||||
Reference in New Issue
Block a user