From 8e00adae426382415bedd563ac3aa284cf78a4ae Mon Sep 17 00:00:00 2001
From: Gerard Wagener <gerard.wagener@circl.lu>
Date: Tue, 4 Dec 2018 14:24:52 +0100
Subject: [PATCH] initialize hmac computations

---
 client/Makefile | 7 +++++--
 client/d4.c     | 8 +++++++-
 client/d4.h     | 3 +++
 3 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/client/Makefile b/client/Makefile
index 1428026..c42a097 100644
--- a/client/Makefile
+++ b/client/Makefile
@@ -1,2 +1,5 @@
-d4:	d4.c
-	gcc -Wall -o d4 d4.c -luuid
+d4:	d4.o others/hmac/sha2.o others/hmac/hmac.o
+	gcc -Wall -o d4 d4.o others/hmac/hmac.o others/hmac/sha2.o -luuid
+
+d4.o:	d4.c
+	gcc -Wall -c d4.c
diff --git a/client/d4.c b/client/d4.c
index 588689a..66256f8 100644
--- a/client/d4.c
+++ b/client/d4.c
@@ -143,6 +143,12 @@ void d4_prepare_header(d4_t* d4)
     }
     // If UUID cannot be parsed it is set to 0
     d4->header.type = atoi(d4->conf[TYPE]);
+
+    d4->ctx = calloc(sizeof(hmac_sha256_ctx),1);
+    if (d4->ctx) {
+        //FIXME check cast of the key
+        hmac_sha256_init(d4->ctx, (uint8_t*)d4->conf[KEY], strlen(d4->conf[KEY]));
+    }
 }
 
 void d4_update_header(d4_t* d4, ssize_t nread) {
@@ -150,7 +156,6 @@ void d4_update_header(d4_t* d4, ssize_t nread) {
     bzero(&tv,sizeof(struct timeval));
     gettimeofday(&tv,NULL);
     d4->header.timestamp = tv.tv_sec;
-    //TODO hmac
     d4->header.size=nread;
 }
 
@@ -172,6 +177,7 @@ void d4_transfert(d4_t* d4)
         nread = read(d4->source.fd, buf, d4->snaplen);
         if ( nread > 0 ) {
             d4_update_header(d4, nread);
+            //TODO hmac header and payload
             write(d4->destination.fd, &d4->header, sizeof(d4->header));
             write(d4->destination.fd,buf,nread);
         } else{
diff --git a/client/d4.h b/client/d4.h
index 756b600..2baba17 100644
--- a/client/d4.h
+++ b/client/d4.h
@@ -1,6 +1,8 @@
 #ifndef D4_H
 #define D4_H
 
+#include "others/hmac/hmac_sha2.h"
+
 #define ND4PARAMS 7
 #define NERRORS 100
 #define SZCONFVALUE 1024
@@ -49,6 +51,7 @@ typedef struct d4_s {
     char errors[NERRORS][SZERRVALUE];
     int err_idx;
     d4_header_t header;
+    hmac_sha256_ctx *ctx;
 } d4_t;