{
int i;
for (i = 0; i < len; i++)
- if (buf[i] != '\r' && (trusted || buf[i] & 0x60))
+ if (buf[i] != '\r' && (trusted || buf[i] == '\n' || (buf[i] & 0x60)))
fputc(buf[i], stderr);
}
while ((argtype = va_arg(ap, int)) != PKT_END) {
unsigned char *argp, argchar;
+ char *sargp;
unsigned long argint;
int arglen;
switch (argtype) {
ssh_pkt_adddata(pkt, argp, arglen);
break;
case PKT_STR:
- argp = va_arg(ap, unsigned char *);
- ssh_pkt_addstring(pkt, argp);
+ sargp = va_arg(ap, char *);
+ ssh_pkt_addstring(pkt, sargp);
break;
case PKT_BIGNUM:
bn = va_arg(ap, Bignum);
static void ssh1_pkt_addmp(struct Packet *pkt, Bignum b)
{
int len = ssh1_bignum_length(b);
- unsigned char *data = snewn(len, char);
+ unsigned char *data = snewn(len, unsigned char);
(void) ssh1_write_bignum(data, b);
ssh_pkt_adddata(pkt, data, len);
sfree(data);
ssh2_pkt_send_noqueue(ssh, pkt);
}
-#if 0 /* disused */
/*
* Either queue or defer a packet, depending on whether queueing is
* set.
else
ssh2_pkt_defer_noqueue(ssh, pkt, FALSE);
}
-#endif
/*
* Send the whole deferred data block constructed by
}
/*
+ * Send a packet whose length needs to be disguised (typically
+ * passwords or keyboard-interactive responses).
+ */
+static void ssh2_pkt_send_with_padding(Ssh ssh, struct Packet *pkt,
+ int padsize)
+{
+#if 0
+ if (0) {
+ /*
+ * The simplest way to do this is to adjust the
+ * variable-length padding field in the outgoing packet.
+ *
+ * Currently compiled out, because some Cisco SSH servers
+ * don't like excessively padded packets (bah, why's it
+ * always Cisco?)
+ */
+ pkt->forcepad = padsize;
+ ssh2_pkt_send(ssh, pkt);
+ } else
+#endif
+ {
+ /*
+ * If we can't do that, however, an alternative approach is
+ * to use the pkt_defer mechanism to bundle the packet
+ * tightly together with an SSH_MSG_IGNORE such that their
+ * combined length is a constant. So first we construct the
+ * final form of this packet and defer its sending.
+ */
+ ssh2_pkt_defer(ssh, pkt);
+
+ /*
+ * Now construct an SSH_MSG_IGNORE which includes a string
+ * that's an exact multiple of the cipher block size. (If
+ * the cipher is NULL so that the block size is
+ * unavailable, we don't do this trick at all, because we
+ * gain nothing by it.)
+ */
+ if (ssh->cscipher) {
+ int stringlen, i;
+
+ stringlen = (256 - ssh->deferred_len);
+ stringlen += ssh->cscipher->blksize - 1;
+ stringlen -= (stringlen % ssh->cscipher->blksize);
+ if (ssh->cscomp) {
+ /*
+ * Temporarily disable actual compression, so we
+ * can guarantee to get this string exactly the
+ * length we want it. The compression-disabling
+ * routine should return an integer indicating how
+ * many bytes we should adjust our string length
+ * by.
+ */
+ stringlen -=
+ ssh->cscomp->disable_compression(ssh->cs_comp_ctx);
+ }
+ pkt = ssh2_pkt_init(SSH2_MSG_IGNORE);
+ ssh2_pkt_addstring_start(pkt);
+ for (i = 0; i < stringlen; i++) {
+ char c = (char) random_byte();
+ ssh2_pkt_addstring_data(pkt, &c, 1);
+ }
+ ssh2_pkt_defer(ssh, pkt);
+ }
+ ssh_pkt_defersend(ssh);
+ }
+}
+
+/*
* Send all queued SSH-2 packets. We send them by means of
* ssh2_pkt_defer_noqueue(), in case they included a pair of
* packets that needed to be lumped together.
ssh->remote_bugs = 0;
+ /*
+ * General notes on server version strings:
+ * - Not all servers reporting "Cisco-1.25" have all the bugs listed
+ * here -- in particular, we've heard of one that's perfectly happy
+ * with SSH1_MSG_IGNOREs -- but this string never seems to change,
+ * so we can't distinguish them.
+ */
if (ssh->cfg.sshbug_ignore1 == FORCE_ON ||
(ssh->cfg.sshbug_ignore1 == AUTO &&
(!strcmp(imp, "1.2.18") || !strcmp(imp, "1.2.19") ||
* magnitude of the password length, but it will
* introduce a bit of extra uncertainty.
*
- * A few servers (the old 1.2.18 through 1.2.22)
- * can't deal with SSH1_MSG_IGNORE. For these
- * servers, we need an alternative defence. We make
- * use of the fact that the password is interpreted
- * as a C string: so we can append a NUL, then some
- * random data.
+ * A few servers can't deal with SSH1_MSG_IGNORE, at
+ * least in this context. For these servers, we need
+ * an alternative defence. We make use of the fact
+ * that the password is interpreted as a C string:
+ * so we can append a NUL, then some random data.
*
- * One server (a Cisco one) can deal with neither
- * SSH1_MSG_IGNORE _nor_ a padded password string.
- * For this server we are left with no defences
+ * A few servers can deal with neither SSH1_MSG_IGNORE
+ * here _nor_ a padded password string.
+ * For these servers we are left with no defences
* against password length sniffing.
*/
- if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE)) {
+ if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE) &&
+ !(ssh->remote_bugs & BUG_NEEDS_SSH1_PLAIN_PASSWORD)) {
/*
* The server can deal with SSH1_MSG_IGNORE, so
* we can use the primary defence.
PKTT_OTHER, PKT_END);
} else {
/*
- * The server has _both_
- * BUG_CHOKES_ON_SSH1_IGNORE and
- * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
- * therefore nothing we can do.
+ * The server is believed unable to cope with
+ * any of our password camouflage methods.
*/
int len;
len = strlen(s->cur_prompt->prompts[0]->result);
/* Data for an agent message. Buffer it. */
while (len > 0) {
if (c->u.a.lensofar < 4) {
- unsigned int l = min(4 - c->u.a.lensofar, len);
+ unsigned int l = min(4 - c->u.a.lensofar, (unsigned)len);
memcpy(c->u.a.msglen + c->u.a.lensofar, p,
l);
p += l;
if (c->u.a.lensofar >= 4 && len > 0) {
unsigned int l =
min(c->u.a.totallen - c->u.a.lensofar,
- len);
+ (unsigned)len);
memcpy(c->u.a.message + c->u.a.lensofar, p,
l);
p += l;
case CHAN_AGENT:
while (length > 0) {
if (c->u.a.lensofar < 4) {
- unsigned int l = min(4 - c->u.a.lensofar, length);
+ unsigned int l = min(4 - c->u.a.lensofar,
+ (unsigned)length);
memcpy(c->u.a.msglen + c->u.a.lensofar,
data, l);
data += l;
if (c->u.a.lensofar >= 4 && length > 0) {
unsigned int l =
min(c->u.a.totallen - c->u.a.lensofar,
- length);
+ (unsigned)length);
memcpy(c->u.a.message + c->u.a.lensofar,
data, l);
data += l;
* Send the responses to the server.
*/
s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE);
- s->pktout->forcepad = 256;
ssh2_pkt_adduint32(s->pktout, s->num_prompts);
for (i=0; i < s->num_prompts; i++) {
dont_log_password(ssh, s->pktout, PKTLOG_BLANK);
s->cur_prompt->prompts[i]->result);
end_log_omission(ssh, s->pktout);
}
- ssh2_pkt_send(ssh, s->pktout);
+ ssh2_pkt_send_with_padding(ssh, s->pktout, 256);
/*
* Get the next packet in case it's another
* people who find out how long their password is!
*/
s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
- s->pktout->forcepad = 256;
ssh2_pkt_addstring(s->pktout, s->username);
ssh2_pkt_addstring(s->pktout, "ssh-connection");
/* service requested */
dont_log_password(ssh, s->pktout, PKTLOG_BLANK);
ssh2_pkt_addstring(s->pktout, s->password);
end_log_omission(ssh, s->pktout);
- ssh2_pkt_send(ssh, s->pktout);
+ ssh2_pkt_send_with_padding(ssh, s->pktout, 256);
logevent("Sent password");
s->type = AUTH_TYPE_PASSWORD;
s->cur_prompt->instruction =
dupprintf("%.*s", prompt_len, prompt);
s->cur_prompt->instr_reqd = TRUE;
+ /*
+ * There's no explicit requirement in the protocol
+ * for the "old" passwords in the original and
+ * password-change messages to be the same, and
+ * apparently some Cisco kit supports password change
+ * by the user entering a blank password originally
+ * and the real password subsequently, so,
+ * reluctantly, we prompt for the old password again.
+ *
+ * (On the other hand, some servers don't even bother
+ * to check this field.)
+ */
+ add_prompt(s->cur_prompt,
+ dupstr("Current password (blank for previously entered password): "),
+ FALSE, SSH_MAX_PASSWORD_LEN);
add_prompt(s->cur_prompt, dupstr("Enter new password: "),
FALSE, SSH_MAX_PASSWORD_LEN);
add_prompt(s->cur_prompt, dupstr("Confirm new password: "),
}
/*
- * Check the two passwords match.
+ * If the user specified a new original password
+ * (IYSWIM), overwrite any previously specified
+ * one.
+ * (A side effect is that the user doesn't have to
+ * re-enter it if they louse up the new password.)
+ */
+ if (s->cur_prompt->prompts[0]->result[0]) {
+ memset(s->password, 0, strlen(s->password));
+ /* burn the evidence */
+ sfree(s->password);
+ s->password =
+ dupstr(s->cur_prompt->prompts[0]->result);
+ }
+
+ /*
+ * Check the two new passwords match.
*/
- got_new = (strcmp(s->cur_prompt->prompts[0]->result,
- s->cur_prompt->prompts[1]->result)
+ got_new = (strcmp(s->cur_prompt->prompts[1]->result,
+ s->cur_prompt->prompts[2]->result)
== 0);
if (!got_new)
/* They don't. Silly user. */
* (see above for padding rationale)
*/
s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
- s->pktout->forcepad = 256;
ssh2_pkt_addstring(s->pktout, s->username);
ssh2_pkt_addstring(s->pktout, "ssh-connection");
/* service requested */
dont_log_password(ssh, s->pktout, PKTLOG_BLANK);
ssh2_pkt_addstring(s->pktout, s->password);
ssh2_pkt_addstring(s->pktout,
- s->cur_prompt->prompts[0]->result);
+ s->cur_prompt->prompts[1]->result);
free_prompts(s->cur_prompt);
end_log_omission(ssh, s->pktout);
- ssh2_pkt_send(ssh, s->pktout);
+ ssh2_pkt_send_with_padding(ssh, s->pktout, 256);
logevent("Sent new password");
/*
projects / u / mdw / putty / blobdiff