readability code clean-up (#550)

* readability code clean-up

* readability code clean-up

include/header_encryption.h

@@ -18,15 +18,13 @@
 
 
 uint32_t packet_header_decrypt (uint8_t packet[], uint16_t packet_len,
-                                char * community_name, he_context_t * ctx,
+                                char *community_name, he_context_t *ctx,
-                                he_context_t * ctx_iv,
+                                he_context_t *ctx_iv,
-                                uint64_t * stamp, uint16_t * checksum);
+                                uint64_t *stamp, uint16_t *checksum);
 
-int32_t packet_header_encrypt (uint8_t packet[], uint8_t header_len, he_context_t * ctx,
+int32_t packet_header_encrypt (uint8_t packet[], uint8_t header_len, he_context_t *ctx,
-                               he_context_t * ctx_iv,
+                               he_context_t *ctx_iv,
                                uint64_t stamp, uint16_t checksum);
 
-
+void packet_header_setup_key (const char *community_name, he_context_t **ctx,
-void packet_header_setup_key (const char * community_name, he_context_t ** ctx,
+                                                          he_context_t **ctx_iv);
-                                                           he_context_t ** ctx_iv);
-

src/header_encryption.c

@@ -19,13 +19,13 @@
 
 #include "n2n.h"
 
+
 #define HASH_FIND_COMMUNITY(head, name, out) HASH_FIND_STR(head, name, out)
 
-/* ********************************************************************** */
 
 uint32_t packet_header_decrypt (uint8_t packet[], uint16_t packet_len,
-			        char * community_name, he_context_t * ctx,
+                                char *community_name, he_context_t *ctx,
-				he_context_t * ctx_iv, uint64_t * stamp, uint16_t * checksum) {
+                                he_context_t *ctx_iv, uint64_t *stamp, uint16_t *checksum) {
 
     // assemble IV
     // the last four are ASCII "n2n!" and do not get overwritten
@@ -33,83 +33,84 @@ uint32_t packet_header_decrypt (uint8_t packet[], uint16_t packet_len,
                        0x00, 0x00, 0x00, 0x00, 0x6E, 0x32, 0x6E, 0x21 };
     // the first 96 bits of the packet get padded with ASCII "n2n!"
     // to full 128 bit IV
-  memcpy (iv, packet, 12);
+    memcpy(iv, packet, 12);
-
 
     // try community name as possible key and check for magic bytes
     uint32_t magic = 0x6E326E00; // ="n2n_"
     uint32_t test_magic;
     // check for magic bytes and reasonable value in header len field
     // so, as a first step, decrypt 4 bytes only starting at byte 12
-  speck_he ((uint8_t*)&test_magic, &packet[12], 4, iv, (speck_context_t*)ctx);
+    speck_he((uint8_t*)&test_magic, &packet[12], 4, iv, (speck_context_t*)ctx);
-  test_magic = be32toh (test_magic);
+    test_magic = be32toh(test_magic);
-  if( (((test_magic >> 8) <<  8) == magic)	// check the thre uppermost bytes
+    if((((test_magic >> 8) <<  8) == magic)         /* check the thre uppermost bytes */
-       && (((uint8_t)test_magic) <= packet_len) // lowest 8 bit of test_magic are header_len
+     && (((uint8_t)test_magic) <= packet_len)) {    /* lowest 8 bit of test_magic are header_len */
-       ) {
         // decrypt the complete header
-    speck_he (&packet[12], &packet[12], (uint8_t)(test_magic) - 12, iv, (speck_context_t*)ctx);
+        speck_he(&packet[12], &packet[12], (uint8_t)(test_magic) - 12, iv, (speck_context_t*)ctx);
 
         // extract time stamp (first 64 bit) and checksum (last 16 bit) blended in IV
-    speck_he_iv_decrypt (iv, (speck_context_t*)ctx_iv);
+        speck_he_iv_decrypt(iv, (speck_context_t*)ctx_iv);
-    *checksum = be16toh (((uint16_t*)iv)[5]);
+        *checksum = be16toh(((uint16_t*)iv)[5]);
-    *stamp    = be64toh (((uint64_t*)iv)[0]);
+        *stamp    = be64toh(((uint64_t*)iv)[0]);
 
         // restore original packet order
-    memcpy (&packet[0], &packet[16], 4);
+        memcpy(&packet[0], &packet[16], 4);
-    memcpy (&packet[4], community_name, N2N_COMMUNITY_SIZE);
+        memcpy(&packet[4], community_name, N2N_COMMUNITY_SIZE);
 
-    return (1); // successful
+        // successful
+        return 1;
     } else {
-    return (0); // unsuccessful
+
+        // unsuccessful
+        return 0;
     }
 }
 
-/* ********************************************************************** */
 
-int32_t packet_header_encrypt (uint8_t packet[], uint8_t header_len, he_context_t * ctx,
+int32_t packet_header_encrypt (uint8_t packet[], uint8_t header_len, he_context_t *ctx,
-                               he_context_t * ctx_iv, uint64_t stamp, uint16_t checksum) {
+                               he_context_t *ctx_iv, uint64_t stamp, uint16_t checksum) {
 
     uint8_t iv[16];
     uint16_t *iv16 = (uint16_t*)&iv;
     uint32_t *iv32 = (uint32_t*)&iv;
     uint64_t *iv64 = (uint64_t*)&iv;
-  const uint32_t magic = 0x6E326E21; // = ASCII "n2n!"
+    const uint32_t magic = 0x6E326E21; /* == ASCII "n2n!" */
 
     if(header_len < 20) {
         traceEvent(TRACE_DEBUG, "packet_header_encrypt dropped a packet too short to be valid.");
-    return (-1);
+        return -1;
       }
 
-  memcpy (&packet[16], &packet[00], 4);
+    memcpy(&packet[16], &packet[00], 4);
+
+    iv64[0] = htobe64(stamp);
+    iv16[4] = n2n_rand();
+    iv16[5] = htobe16(checksum);
+    iv32[3] = htobe32(magic);
 
-  iv64[0] = htobe64 (stamp);
-  iv16[4] = n2n_rand ();
-  iv16[5] = htobe16 (checksum);
-  iv32[3] = htobe32 (magic);
     // blend checksum into 96-bit IV
-  speck_he_iv_encrypt (iv, (speck_context_t*)ctx_iv);
+    speck_he_iv_encrypt(iv, (speck_context_t*)ctx_iv);
 
-  memcpy (packet, iv, 16);
+    memcpy(packet, iv, 16);
     packet[15] = header_len;
 
-  speck_he (&packet[12], &packet[12], header_len - 12, iv, (speck_context_t*)ctx);
+    speck_he(&packet[12], &packet[12], header_len - 12, iv, (speck_context_t*)ctx);
-  return (0);
+
+    return 0;
 }
 
-/* ********************************************************************** */
 
-void packet_header_setup_key (const char * community_name, he_context_t ** ctx,
+void packet_header_setup_key (const char *community_name, he_context_t **ctx,
-                                                           he_context_t ** ctx_iv) {
+                                                          he_context_t **ctx_iv) {
 
     uint8_t key[16];
-  pearson_hash_128 (key, (uint8_t*)community_name, N2N_COMMUNITY_SIZE);
+    pearson_hash_128(key, (uint8_t*)community_name, N2N_COMMUNITY_SIZE);
 
     *ctx = (he_context_t*)calloc(1, sizeof (speck_context_t));
-  speck_expand_key_he (key, (speck_context_t*)*ctx);
+    speck_expand_key_he(key, (speck_context_t*)*ctx);
 
     // hash again and use last 96 bit (skipping 4 bytes) as key for IV encryption
     // REMOVE as soon as checksum and replay protection get their own fields
-  pearson_hash_128 (key, key, sizeof (key));
+    pearson_hash_128(key, key, sizeof (key));
     *ctx_iv = (he_context_t*)calloc(1, sizeof (speck_context_t));
-  speck_expand_key_he_iv (&key[4], (speck_context_t*)*ctx_iv);
+    speck_expand_key_he_iv(&key[4], (speck_context_t*)*ctx_iv);
 }