# HG changeset patch
# User Matt Johnston <matt@ucc.asn.au>
# Date 1518867704 -28800
# Node ID b024f96957826d3cf176e8b32d8eb779c0241c77
# Parent  5916af64acd4c0b73fd3f2352af14229c5ce69cb
limit rsa->e size to 64 bits

diff -r 5916af64acd4 -r b024f9695782 rsa.c
--- a/rsa.c	Sat Feb 17 19:29:51 2018 +0800
+++ b/rsa.c	Sat Feb 17 19:41:44 2018 +0800
@@ -68,6 +68,12 @@
 		goto out;
 	}
 
+	/* 64 bit is limit used by openssl, so we won't block any keys in the wild */
+	if (mp_count_bits(key->e) > 64) {
+		dropbear_log(LOG_WARNING, "RSA key bad e");
+		goto out;
+	}
+
 	TRACE(("leave buf_get_rsa_pub_key: success"))
 	ret = DROPBEAR_SUCCESS;
 out: