Further refactored code and dealt with the verifier issues with string comparisons

src/include/packet/packet_manager.h

@@ -27,6 +27,13 @@ static __always_inline int tcp_header_bound_check(struct tcphdr* tcp, void* data
     return 0; //OK
 }
 
+static __always_inline int tcp_payload_bound_check(char* payload, int payload_size, void* data_end){
+    if ((void *)payload + payload_size > data_end){
+        return -1;
+    }
+    return 0; //OK
+}
+
 
 
 /* UTILITIES */
@@ -44,4 +51,8 @@ static __always_inline int get_protocol(void* data){
     }
 }
 
+static __always_inline unsigned char* get_payload(struct tcphdr *tcp){
+    return (void *)tcp + tcp->doff*4;
+}
+
 #endif

src/include/packet/protocol/tcp_helper.h

@@ -0,0 +1,16 @@
+#ifndef __TCP_HELPER_H__
+#define __TCP_HELPER_H__
+
+#include <linux/tcp.h>
+#include <linux/ip.h>
+
+
+static __always_inline int get_tcp_src_port(struct tcphdr *tcp){
+    return ntohs(tcp->source);
+}
+
+static __always_inline int get_tcp_dest_port(struct tcphdr *tcp){
+    return ntohs(tcp->dest);
+}
+
+#endif