1 files changed, 34 insertions, 7 deletions
diff --git a/scripts/pem_to_pub_c.py b/scripts/pem_to_pub_c.py
index 47c004d..92f4b81 100755
--- a/scripts/pem_to_pub_c.py
+++ b/scripts/pem_to_pub_c.py
@@ -26,6 +26,33 @@
 # POSSIBILITY OF SUCH DAMAGE.
 #
 
+from collections import namedtuple
+PublicKey = namedtuple("PublicKey", "e n")
+
+def importKey_crypto(pem_key_file):
+	try:
+		module = __import__("Crypto.PublicKey.RSA")
+		f = open(pem_key_file, 'r')
+		key = module.PublicKey.RSA.importKey(f.read())
+		f.close()
+		return PublicKey(e=key.publickey().e, n=module.Util.number.long_to_bytes(key.publickey().n))
+	except ImportError:
+		return None
+
+def importKey_openssl(pem_key_file):
+	import subprocess
+	cmd = "cat " + pem_key_file + " | openssl rsa -inform PEM -noout -text | grep publicE | sed 's/publicExponent: //' | cut -d ' ' -f1 | tr -d '\n'"
+	e = subprocess.check_output(cmd, shell=True, stderr=subprocess.STDOUT)
+	if not e:
+		print "Exporting exponent value from key {0} has failed.".format(pem_key_file)
+                return None
+	cmd = "cat " + pem_key_file + " | openssl rsa -inform PEM -noout -modulus | sed 's/Modulus=//' | tr -d '\n'"
+	n = subprocess.check_output(cmd, shell=True, stderr=subprocess.STDOUT)
+	if not n:
+		print "Exporting modulus value from key {0} has failed.".format(pem_key_file)
+		return None
+	return PublicKey(e=e, n=n.decode("hex"))
+
 def get_args():
 	import argparse
 
@@ -42,14 +69,14 @@ def get_args():
 
 def main():
 	import array
-	from Crypto.PublicKey import RSA
-	from Crypto.Util.number import long_to_bytes
 
 	args = get_args();
 
-	f = open(args.key, 'r')
-	key = RSA.importKey(f.read())
-	f.close
+	key = importKey_crypto(args.key)
+	if key is None:
+		key = importKey_openssl(args.key)
+		if key is None:
+			return
 
 	f = open(args.out, 'w')
 
@@ -57,11 +84,11 @@ def main():
 	f.write("#include <stddef.h>\n\n");
 
 	f.write("const uint32_t " + args.prefix + "_exponent = " +
-		str(key.publickey().e) + ";\n\n")
+		str(key.e) + ";\n\n")
 
 	f.write("const uint8_t " + args.prefix + "_modulus[] = {\n")
 	i = 0;
-	for x in array.array("B", long_to_bytes(key.publickey().n)):
+	for x in array.array("B", key.n):
 		f.write("0x" + '{0:02x}'.format(x) + ",")
 		i = i + 1;
 		if i % 8 == 0: