DCCP: Fix printing "Timestamp" and "Timestamp Echo" options
Add some comments.
Moreover:
Put a function definition name at the beginning of the line.
diff --git a/print-dccp.c b/print-dccp.c
index 11c6d75..407ec2d 100644
--- a/print-dccp.c
+++ b/print-dccp.c
@@ -537,7 +537,8 @@
{ 0, NULL }
};
-static u_int dccp_print_option(netdissect_options *ndo, const u_char *option, u_int hlen)
+static u_int
+dccp_print_option(netdissect_options *ndo, const u_char *option, u_int hlen)
{
uint8_t optlen, i;
@@ -630,16 +631,54 @@
}
break;
case 41:
- if (optlen == 4)
+ /*
+ * 13.1. Timestamp Option
+ *
+ * +--------+--------+--------+--------+--------+--------+
+ * |00101001|00000110| Timestamp Value |
+ * +--------+--------+--------+--------+--------+--------+
+ * Type=41 Length=6
+ */
+ if (optlen == 6)
ND_PRINT(" %u", EXTRACT_BE_U_4(option + 2));
else
- ND_PRINT(" optlen != 4");
+ ND_PRINT(" [optlen != 6]");
break;
case 42:
- if (optlen == 4)
+ /*
+ * 13.3. Timestamp Echo Option
+ *
+ * +--------+--------+--------+--------+--------+--------+
+ * |00101010|00000110| Timestamp Echo |
+ * +--------+--------+--------+--------+--------+--------+
+ * Type=42 Len=6
+ *
+ * +--------+--------+------- ... -------+--------+--------+
+ * |00101010|00001000| Timestamp Echo | Elapsed Time |
+ * +--------+--------+------- ... -------+--------+--------+
+ * Type=42 Len=8 (4 bytes)
+ *
+ * +--------+--------+------- ... -------+------- ... -------+
+ * |00101010|00001010| Timestamp Echo | Elapsed Time |
+ * +--------+--------+------- ... -------+------- ... -------+
+ * Type=42 Len=10 (4 bytes) (4 bytes)
+ */
+ switch (optlen) {
+ case 6:
ND_PRINT(" %u", EXTRACT_BE_U_4(option + 2));
- else
- ND_PRINT(" optlen != 4");
+ break;
+ case 8:
+ ND_PRINT(" %u", EXTRACT_BE_U_4(option + 2));
+ ND_PRINT(" (elapsed time %u)", EXTRACT_BE_U_2(option + 6));
+ break;
+ case 10:
+ ND_PRINT(" %u", EXTRACT_BE_U_4(option + 2));
+ ND_PRINT(" (elapsed time %u)", EXTRACT_BE_U_4(option + 6));
+ break;
+ default:
+ ND_PRINT(" [optlen != 6 or 8 or 10]");
+ break;
+ }
break;
case 43:
if (optlen == 6)
@@ -647,7 +686,7 @@
else if (optlen == 4)
ND_PRINT(" %u", EXTRACT_BE_U_2(option + 2));
else
- ND_PRINT(" optlen != 4 or 6");
+ ND_PRINT(" [optlen != 4 or 6]");
break;
case 44:
if (optlen > 2) {
