make sure # of response matches # of queries, fixes int overflow; from ISS

1 files changed, 12 insertions, 6 deletions

diff --git a/usr.bin/ssh/auth2-chall.c b/usr.bin/ssh/auth2-chall.c
index f35bfb2f8ee..e1440f47d7c 100644
--- a/usr.bin/ssh/auth2-chall.c
+++ b/usr.bin/ssh/auth2-chall.c
@@ -23,7 +23,7 @@
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 #include "includes.h"
-RCSID("$OpenBSD: auth2-chall.c,v 1.18 2002/06/19 00:27:55 deraadt Exp $");
+RCSID("$OpenBSD: auth2-chall.c,v 1.19 2002/06/26 13:55:37 markus Exp $");
 
 #include "ssh2.h"
 #include "auth.h"
@@ -63,6 +63,7 @@ struct KbdintAuthctxt
 	char *devices;
 	void *ctxt;
 	KbdintDevice *device;
+	u_int nreq;
 };
 
 static KbdintAuthctxt *
@@ -90,6 +91,7 @@ kbdint_alloc(const char *devs)
 	debug("kbdint_alloc: devices '%s'", kbdintctxt->devices);
 	kbdintctxt->ctxt = NULL;
 	kbdintctxt->device = NULL;
+	kbdintctxt->nreq = 0;
 
 	return kbdintctxt;
 }
@@ -209,26 +211,26 @@ send_userauth_info_request(Authctxt *authctxt)
 	KbdintAuthctxt *kbdintctxt;
 	char *name, *instr, **prompts;
 	int i;
-	u_int numprompts, *echo_on;
+	u_int *echo_on;
 
 	kbdintctxt = authctxt->kbdintctxt;
 	if (kbdintctxt->device->query(kbdintctxt->ctxt,
-	    &name, &instr, &numprompts, &prompts, &echo_on))
+	    &name, &instr, &kbdintctxt->nreq, &prompts, &echo_on))
 		return 0;
 
 	packet_start(SSH2_MSG_USERAUTH_INFO_REQUEST);
 	packet_put_cstring(name);
 	packet_put_cstring(instr);
 	packet_put_cstring("");		/* language not used */
-	packet_put_int(numprompts);
-	for (i = 0; i < numprompts; i++) {
+	packet_put_int(kbdintctxt->nreq);
+	for (i = 0; i < kbdintctxt->nreq; i++) {
 		packet_put_cstring(prompts[i]);
 		packet_put_char(echo_on[i]);
 	}
 	packet_send();
 	packet_write_wait();
 
-	for (i = 0; i < numprompts; i++)
+	for (i = 0; i < kbdintctxt->nreq; i++)
 		xfree(prompts[i]);
 	xfree(prompts);
 	xfree(echo_on);
@@ -256,6 +258,10 @@ input_userauth_info_response(int type, u_int32_t seq, void *ctxt)
 
 	authctxt->postponed = 0;	/* reset */
 	nresp = packet_get_int();
+	if (nresp != kbdintctxt->nreq)
+		fatal("input_userauth_info_response: wrong number of replies");
+	if (nresp > 100)
+		fatal("input_userauth_info_response: too many replies");
 	if (nresp > 0) {
 		response = xmalloc(nresp * sizeof(char*));
 		for (i = 0; i < nresp; i++)