diff --git a/src/common/f8.c b/src/common/f8.c
new file mode 100644
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--- /dev/null
+++ b/src/common/f8.c
@@ -0,0 +1,80 @@
+
+#include "f8.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+
+
+/* The code has been referred from
+ *
+ * 1.https://www.gsma.com/aboutus/wp-content/uploads/2014/12/uea2uia2d1v21.pdf
+ * 2.https://www.gsma.com/aboutus/wp-content/uploads/2014/12/snow3gspec.pdf
+ *
+ */
+
+
+
+/* f8.
+ * Input key: 128 bit Confidentiality Key.
+ * Input count:32-bit Count, Frame dependent input.
+ * Input bearer: 5-bit Bearer identity (in the LSB side).
+ * Input dir:1 bit, direction of transmission.
+ * Input data: length number of bits, input bit stream.
+ * Input length: 32 bit Length, i.e., the number of bits to be encrypted or
+ * decrypted.
+ * Output data: Output bit stream. Assumes data is suitably memory
+ * allocated.
+ * Encrypts/decrypts blocks of data between 1 and 2^32 bits in length as
+ * defined in Section 3.
+ */
+
+void f8( u8 *key, u32 count, u32 bearer, u32 dir, u8 *data, u32 length )
+{
+	u32 K[4],IV[4];
+	int n = ( length + 31 ) / 32;
+	int i=0;
+	u32 *KS;
+
+	/*Initialisation*/
+
+	/* Load the confidentiality key for SNOW 3G initialization as in section
+		3.4.(https://www.gsma.com/aboutus/wp-content/uploads/2014/12/snow3gspec.pdf)
+	*/
+
+	for (i=0; i<4; i++)
+		K[3-i] = (key[4*i] << 24) ^ (key[4*i+1] << 16) ^ (key[4*i+2] << 8) ^
+		(key[4*i+3]);
+
+	/* Prepare the initialization vector (IV) for SNOW 3G initialization as in
+	section 3.4.(https://www.gsma.com/aboutus/wp-content/uploads/2014/12/snow3gspec.pdf) */
+
+
+	IV[3] = count;
+	IV[2] = (bearer << 27) | ((dir & 0x1) << 26);
+	IV[1] = IV[3];
+	IV[0] = IV[2];
+
+	/* Run SNOW 3G algorithm to generate sequence of key stream bits KS*/
+
+	Initialize(K,IV);
+	KS = (u32 *)malloc(4*n);
+	GenerateKeystream(n,(u32*)KS);
+
+	/* Exclusive-OR the input data with keystream to generate the output bit
+	stream */
+
+	for (i=0; i<n; i++)
+	{
+		data[4*i+0] ^= (u8) (KS[i] >> 24) & 0xff;
+		data[4*i+1] ^= (u8) (KS[i] >> 16) & 0xff;
+		data[4*i+2] ^= (u8) (KS[i] >> 8) & 0xff;
+		data[4*i+3] ^= (u8) (KS[i] ) & 0xff;
+	}
+
+	free(KS);
+
+}
+/* End of f8.c */
+
+