# HG changeset patch
# User Matt Johnston <matt@ucc.asn.au>
# Date 1518867704 -28800
# Node ID 36ab6b091ad3b094469c4a488a1b6424b0e845f4
# Parent  10994a613a6b5ff728d1449418907ffb5dba1d05
limit rsa->e size to 64 bits

diff -r 10994a613a6b -r 36ab6b091ad3 rsa.c
--- a/rsa.c	Tue Feb 20 19:30:34 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: