- 1.47 Thu Feb 8 23:11:42 GMT 2001 by dugsong
[serverloop.c sshconnect1.c]
mitigate SSH1 traffic analysis - from Solar Designer
<solar@openwall.com>, ok provos@
diff --git a/ChangeLog b/ChangeLog
index fe271d6..d4fb242 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -92,6 +92,10 @@
- itojun@cvs.openbsd.org 2001/02/07 18:04:50
[xmalloc.c]
fix size_t -> int cast (use u_long). markus ok
+ - 1.47 Thu Feb 8 23:11:42 GMT 2001 by dugsong
+ [serverloop.c sshconnect1.c]
+ mitigate SSH1 traffic analysis - from Solar Designer
+ <solar@openwall.com>, ok provos@
- (bal) fixed sftp-client.c. Return 'status' instead of '0'
(from the OpenBSD tree)
- (bal) Synced ssh.1, ssh-add.1 and sshd.8 w/ OpenBSD
@@ -3880,4 +3884,4 @@
- Wrote replacements for strlcpy and mkdtemp
- Released 1.0pre1
-$Id: ChangeLog,v 1.736 2001/02/10 23:34:54 mouring Exp $
+$Id: ChangeLog,v 1.737 2001/02/10 23:44:47 mouring Exp $
diff --git a/serverloop.c b/serverloop.c
index c8187ab..8fc94db 100644
--- a/serverloop.c
+++ b/serverloop.c
@@ -35,7 +35,7 @@
*/
#include "includes.h"
-RCSID("$OpenBSD: serverloop.c,v 1.46 2001/02/08 19:30:52 itojun Exp $");
+RCSID("$OpenBSD: serverloop.c,v 1.47 2001/02/08 23:11:42 dugsong Exp $");
#include "xmalloc.h"
#include "packet.h"
@@ -317,6 +317,7 @@
void
process_output(fd_set * writeset)
{
+ struct termios tio;
int len;
/* Write buffered data to program stdin. */
@@ -336,7 +337,16 @@
#endif
fdin = -1;
} else {
- /* Successful write. Consume the data from the buffer. */
+ /* Successful write. */
+ if (tcgetattr(fdin, &tio) == 0 &&
+ !(tio.c_lflag & ECHO)) {
+ /* Simulate echo to reduce the impact of traffic analysis. */
+ packet_start(SSH_MSG_IGNORE);
+ memset(buffer_ptr(&stdin_buffer), 0, len);
+ packet_put_string(buffer_ptr(&stdin_buffer), len);
+ packet_send();
+ }
+ /* Consume the data from the buffer. */
buffer_consume(&stdin_buffer, len);
/* Update the count of bytes written to the program. */
stdin_bytes += len;
diff --git a/sshconnect1.c b/sshconnect1.c
index c33ac50..a71d28c 100644
--- a/sshconnect1.c
+++ b/sshconnect1.c
@@ -13,7 +13,7 @@
*/
#include "includes.h"
-RCSID("$OpenBSD: sshconnect1.c,v 1.24 2001/02/08 19:30:52 itojun Exp $");
+RCSID("$OpenBSD: sshconnect1.c,v 1.25 2001/02/08 23:11:43 dugsong Exp $");
#include <openssl/bn.h>
#include <openssl/evp.h>
@@ -51,6 +51,20 @@
extern Options options;
extern char *__progname;
+void
+ssh1_put_password(char *password)
+{
+ int size;
+ char *padded;
+
+ size = roundup(strlen(password), 32);
+ padded = xmalloc(size);
+ strlcpy(padded, password, size);
+ packet_put_string(padded, size);
+ memset(padded, 0, size);
+ xfree(padded);
+}
+
/*
* Checks if the user has an authentication agent, and if so, tries to
* authenticate using the agent.
@@ -658,7 +672,7 @@
break;
}
packet_start(SSH_CMSG_AUTH_TIS_RESPONSE);
- packet_put_string(response, strlen(response));
+ ssh1_put_password(response);
memset(response, 0, strlen(response));
xfree(response);
packet_send();
@@ -691,7 +705,7 @@
error("Permission denied, please try again.");
password = read_passphrase(prompt, 0);
packet_start(SSH_CMSG_AUTH_PASSWORD);
- packet_put_string(password, strlen(password));
+ ssh1_put_password(password);
memset(password, 0, strlen(password));
xfree(password);
packet_send();