Make session id a uint64_t as it is expected at receiver

1 files changed, 7 insertions, 5 deletions

diff --git a/sender.c b/sender.c
index 3469735..19a3bed 100644
--- a/sender.c
+++ b/sender.c
@@ -27,7 +27,7 @@ static const unsigned char pubkey[] =
 static const unsigned char pp[] = "IJUHZGFDXTZKHJKHGFDHZLUÖDRTFGHHJGHH";
 
 enum { SESSION_ID_LENGTH = 8, AES_KEY_LENGTH = 16, GCM_IV_LENGTH = 16, GCM_TAG_LENGTH = 16 };
-static uint8_t session_id[8] = { 0xef, 0xcd, 0xab, 0x89, 0x67, 0x45, 0x23, 0x01 };
+static uint64_t session_id = 0x0123456789abcdef;
 static uint8_t aes_key[16] = { 0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef };
 
 void send_udp(int sock, mbedtls_ctr_drbg_context *ctr_drbg, const uint8_t *text, size_t len) {
@@ -37,14 +37,14 @@ void send_udp(int sock, mbedtls_ctr_drbg_context *ctr_drbg, const uint8_t *text,
     const size_t total_length = 1 + SESSION_ID_LENGTH + GCM_IV_LENGTH + GCM_TAG_LENGTH + len;
     uint8_t *output = alloca(total_length);
     output[0] = 1;
-    memcpy(output + 1, session_id, SESSION_ID_LENGTH);
+    memcpy(output + 1, (uint8_t*)&session_id, SESSION_ID_LENGTH);
     memcpy(output + 1 + SESSION_ID_LENGTH, iv, GCM_IV_LENGTH);
 
     mbedtls_gcm_context ctx;
     mbedtls_gcm_init(&ctx);
     mbedtls_gcm_setkey(&ctx, MBEDTLS_CIPHER_ID_AES, aes_key, 8 * AES_KEY_LENGTH);
 
-    if (!mbedtls_gcm_crypt_and_tag(&ctx, MBEDTLS_GCM_ENCRYPT, len, iv, GCM_IV_LENGTH, session_id, SESSION_ID_LENGTH,
+    if (!mbedtls_gcm_crypt_and_tag(&ctx, MBEDTLS_GCM_ENCRYPT, len, iv, GCM_IV_LENGTH, (uint8_t*)&session_id, SESSION_ID_LENGTH,
                                   text, output + 1 + SESSION_ID_LENGTH + GCM_IV_LENGTH + GCM_TAG_LENGTH, GCM_TAG_LENGTH,
                                   output + 1 + SESSION_ID_LENGTH + GCM_IV_LENGTH)) {
         struct sockaddr_in to;
@@ -60,12 +60,12 @@ void send_udp(int sock, mbedtls_ctr_drbg_context *ctr_drbg, const uint8_t *text,
 }
 
 void new_session(int sock, mbedtls_ctr_drbg_context *ctr_drbg) {
-    mbedtls_ctr_drbg_random(ctr_drbg, session_id, sizeof(session_id));
+    mbedtls_ctr_drbg_random(ctr_drbg, (uint8_t*)&session_id, sizeof(session_id));
     mbedtls_ctr_drbg_random(ctr_drbg, aes_key, sizeof(aes_key));
 
     unsigned char output[512];
     output[0] = 0;
-    memcpy(output + 1, session_id, SESSION_ID_LENGTH);
+    memcpy(output + 1, (uint8_t*)&session_id, SESSION_ID_LENGTH);
 
     mbedtls_pk_context pk;
     mbedtls_pk_init(&pk);
@@ -105,6 +105,8 @@ int main() {
 
     const unsigned char *logline = (const unsigned char*)"Juchuuu, es klappt!\n";
     send_udp(sock, &ctr_drbg, logline, strlen((char*)logline));
+    send_udp(sock, &ctr_drbg, logline, strlen((char*)logline));
+    send_udp(sock, &ctr_drbg, logline, strlen((char*)logline));
 
     close(sock);
 }