]> The Tcpdump Group git mirrors - tcpdump/blobdiff - print-openflow.c
OpenFlow: Fix a compiler error on Windows. [skip travis]
[tcpdump] / print-openflow.c
index 87a68a47cafef11484f19de94c4c40ec5bafecb9..2b821880ac3c9910dce8b41abf41bf4b86fac46d 100644 (file)
@@ -38,6 +38,7 @@
 
 #include "netdissect-stdinc.h"
 
+#define ND_LONGJMP_FROM_TCHECK
 #include "netdissect.h"
 #include "extract.h"
 #include "openflow.h"
 
 
 #define OF_VER_1_0    0x01
+#define OF_VER_1_1    0x02
+#define OF_VER_1_2    0x03
+#define OF_VER_1_3    0x04
+#define OF_VER_1_4    0x05
+#define OF_VER_1_5    0x06
+
+static const struct tok ofver_str[] = {
+       { OF_VER_1_0,   "1.0" },
+       { OF_VER_1_1,   "1.1" },
+       { OF_VER_1_2,   "1.2" },
+       { OF_VER_1_3,   "1.3" },
+       { OF_VER_1_4,   "1.4" },
+       { OF_VER_1_5,   "1.5" },
+       { 0, NULL }
+};
 
 const struct tok onf_exp_str[] = {
        { ONF_EXP_ONF,               "ONF Extensions"                                  },
@@ -65,12 +81,18 @@ of_vendor_name(const uint32_t vendor)
        return tok2str(table, "unknown", vendor);
 }
 
-static void
-of_header_print(netdissect_options *ndo, const uint8_t version, const uint8_t type,
-                      const uint16_t length, const uint32_t xid)
+void
+of_data_print(netdissect_options *ndo,
+              const u_char *cp, const u_int len)
 {
-       ND_PRINT("\n\tversion unknown (0x%02x), type 0x%02x, length %u, xid 0x%08x",
-              version, type, length, xid);
+       if (len == 0)
+               return;
+       /* data */
+       ND_PRINT("\n\t data (%u octets)", len);
+       if (ndo->ndo_vflag >= 2)
+               hex_and_ascii_print(ndo, "\n\t  ", cp, len);
+       else
+               ND_TCHECK_LEN(cp, len);
 }
 
 /* Print a TCP segment worth of OpenFlow messages presuming the segment begins
@@ -84,23 +106,50 @@ openflow_print(netdissect_options *ndo, const u_char *cp, u_int len)
                /* Print a single OpenFlow message. */
                uint8_t version, type;
                uint16_t length;
-               uint32_t xid;
+               void (*decoder)(struct netdissect_options *,
+                               const u_char *, uint16_t, const uint8_t) = NULL;
 
-               if (len < OF_HEADER_FIXLEN)
-                       goto invalid;
                /* version */
                version = GET_U_1(cp);
                OF_FWD(1);
+               ND_PRINT("\n\tversion %s",
+                        tok2str(ofver_str, "unknown (0x%02x)", version));
                /* type */
+               if (len < 1)
+                       goto partial_header;
                type = GET_U_1(cp);
                OF_FWD(1);
+               switch (version) {
+               case OF_VER_1_0:
+                       ND_PRINT(", type %s", of10_msgtype_str(type));
+                       decoder = of10_message_print;
+                       break;
+               case OF_VER_1_3:
+                       ND_PRINT(", type %s", of13_msgtype_str(type));
+                       decoder = of13_message_print;
+                       break;
+               default:
+                       ND_PRINT(", type unknown (0x%02x)", type);
+               }
                /* length */
+               if (len < 2)
+                       goto partial_header;
                length = GET_BE_U_2(cp);
                OF_FWD(2);
+               ND_PRINT(", length %u%s", length,
+                        length < OF_HEADER_FIXLEN ? " (too short!)" : "");
                /* xid */
-               xid = GET_BE_U_4(cp);
+               if (len < 4)
+                       goto partial_header;
+               ND_PRINT(", xid 0x%08x", GET_BE_U_4(cp));
                OF_FWD(4);
+
                /*
+                * When a TCP packet can contain several protocol messages,
+                * and at the same time a protocol message can span several
+                * TCP packets, decoding an incomplete message at the end of
+                * a TCP packet requires attention to detail in this loop.
+                *
                 * Message length includes the header length and a message
                 * always includes the basic header. A message length underrun
                 * fails decoding of the rest of the current packet. At the
@@ -108,37 +157,37 @@ openflow_print(netdissect_options *ndo, const u_char *cp, u_int len)
                 * possible even when it does not end within the current TCP
                 * segment.
                 *
-                * That is, do NOT require the header "length" to be small
+                * Specifically, to try to process the message body in this
+                * iteration do NOT require the header "length" to be small
                 * enough for the full declared OpenFlow message to fit into
                 * the remainder of the declared TCP segment, same as the full
                 * declared TCP segment is not required to fit into the
                 * captured packet buffer.
+                *
+                * But DO require the same at the end of this iteration to
+                * decrement "len" and to proceed to the next iteration.
+                * (Ideally the declared TCP payload end will be at or after
+                * the captured packet buffer end, but stay safe even when
+                * that's somehow not the case.)
                 */
-               if (length < OF_HEADER_FIXLEN) {
-                       of_header_print(ndo, version, type, length, xid);
+               if (length < OF_HEADER_FIXLEN)
                        goto invalid;
-               }
-               /*
-                * Decode known protocol versions further without printing the
-                * header (the type decoding is version-specific).
-                */
-               switch (version) {
-               case OF_VER_1_0:
-                       of10_header_body_print(ndo, cp, type,
-                                              length - OF_HEADER_FIXLEN, xid);
-                       break;
-               default:
-                       of_header_print(ndo, version, type, length, xid);
+
+               if (decoder != NULL)
+                       decoder(ndo, cp, length - OF_HEADER_FIXLEN, type);
+               else
                        ND_TCHECK_LEN(cp, length - OF_HEADER_FIXLEN);
-               }
+               if (length - OF_HEADER_FIXLEN > len)
+                       break;
                OF_FWD(length - OF_HEADER_FIXLEN);
        } /* while (len) */
        return;
 
+partial_header:
+       ND_PRINT(" (end of TCP payload)");
+       ND_TCHECK_LEN(cp, len);
+       return;
 invalid: /* fail the current packet */
        nd_print_invalid(ndo);
        ND_TCHECK_LEN(cp, len);
-       return;
-trunc:
-       nd_trunc(ndo);
 }