macsec: more cleanups.

Get rid of code that knows about Ethernet; this is 802.1AE, not 802.3AE.

Get rid o some unused variables.

diff --git a/netdissect.h b/netdissect.h
index 88055b4a127ab5eef95083189cab89307f7b4c52..2f25d4167e0f78b1df548fa1c852eb558fe316e0 100644 (file)
--- a/netdissect.h
+++ b/netdissect.h
@@ -629,8 +629,7 @@ extern void lwapp_data_print(netdissect_options *, const u_char *, u_int);
 extern void lwres_print(netdissect_options *, const u_char *, u_int);
 extern void m3ua_print(netdissect_options *, const u_char *, const u_int);
 extern int macsec_print(netdissect_options *, const u_char **,
-                        u_int *, u_int *, u_int *,
-                        u_short *);
+                        u_int *, u_int *, u_int *);
 extern u_int mfr_print(netdissect_options *, const u_char *, u_int);
 extern void mobile_print(netdissect_options *, const u_char *, u_int);
 extern int mobility_print(netdissect_options *, const u_char *, const u_char *);

diff --git a/print-ether.c b/print-ether.c
index 4dd253ac621d31dbfca3010b282f5c2187716ac0..0d8dbba9678058c4fa65f7534b7e5f8173f46f78 100644 (file)
--- a/print-ether.c
+++ b/print-ether.c
@@ -209,7 +209,7 @@ recurse:
                 * MACsec, aka IEEE 802.1AE-2006
                 * Print the header, and try to print the payload if it's not encrypted
                 */
-               int ret = macsec_print(ndo, &p, &length, &caplen, &hdrlen, &length_type);
+               int ret = macsec_print(ndo, &p, &length, &caplen, &hdrlen);
 
                if (ret == 0) {
                        /* Payload is encrypted; just quit. */
@@ -217,6 +217,11 @@ recurse:
                } else if (ret > 0) {
                        /* Problem printing the header; just quit. */
                        return (ret);
+               } else {
+                       /*
+                        * Keep processing type/length fields.
+                        */
+                       goto recurse;
                }
        }
 

diff --git a/print-macsec.c b/print-macsec.c
index 917c1c7e318dd1151fb7230280ca1a243478b14f..e5030588587d784def81b73bb4b727686eb80482 100644 (file)
--- a/print-macsec.c
+++ b/print-macsec.c
@@ -34,8 +34,6 @@
 #include "ethertype.h"
 #include "extract.h"
 
-static const char tstr[] = "[|MACsec]";
-
 #define MACSEC_DEFAULT_ICV_LEN 16
 
 /* Header format (SecTAG), following an Ethernet header
@@ -77,40 +75,8 @@ struct macsec_sectag {
 #define MACSEC_TCI_CONFID  (MACSEC_TCI_E | MACSEC_TCI_C)
 #define MACSEC_SL_MASK     0x3F /* short length */
 
-#define MACSEC_SECTAG_LEN_NOSCI 6
-#define MACSEC_SECTAG_LEN_SCI 14
-static int
-ieee8021ae_sectag_len(netdissect_options *ndo, const struct macsec_sectag *sectag)
-{
-       return (GET_U_1(sectag->tci_an) & MACSEC_TCI_SC) ?
-              MACSEC_SECTAG_LEN_SCI :
-              MACSEC_SECTAG_LEN_NOSCI;
-}
-
-static int macsec_check_length(netdissect_options *ndo, const struct macsec_sectag *sectag, u_int length, u_int caplen)
-{
-       u_int len;
-
-       /* we need the full MACsec header in the capture */
-       if (caplen < (MACSEC_SECTAG_LEN_NOSCI + 2))
-               return 0;
-
-       len = ieee8021ae_sectag_len(ndo, sectag);
-       if (caplen < (len + 2))
-               return 0;
-
-       if ((GET_U_1(sectag->short_length) & MACSEC_SL_MASK) != 0) {
-               /* original packet must have exact length */
-               u_int exact = ETHER_HDRLEN + len + 2 + (GET_U_1(sectag->short_length) & MACSEC_SL_MASK);
-               return exact == length;
-       } else {
-               /* original packet must not be short */
-               u_int minlen = ETHER_HDRLEN + len + 2 + 48;
-               return length >= minlen;
-       }
-
-       return 1;
-}
+#define MACSEC_SECTAG_LEN_NOSCI 6  /* length of MACsec header without SCI */
+#define MACSEC_SECTAG_LEN_SCI   14 /* length of MACsec header with SCI */
 
 #define SCI_FMT "%016" PRIx64
 
@@ -125,24 +91,40 @@ static const struct tok macsec_flag_values[] = {
 
 /* returns < 0 iff the packet can be decoded completely */
 int macsec_print(netdissect_options *ndo, const u_char **bp,
-                u_int *lengthp, u_int *caplenp, u_int *hdrlenp,
-                u_short *length_type)
+                u_int *lengthp, u_int *caplenp, u_int *hdrlenp)
 {
+       const char *save_protocol;
        const u_char *p = *bp;
        u_int length = *lengthp;
        u_int caplen = *caplenp;
        u_int hdrlen = *hdrlenp;
        const struct macsec_sectag *sectag = (const struct macsec_sectag *)p;
-       u_int len;
+       u_int sectag_len;
 
-       if (!macsec_check_length(sectag, length, caplen)) {
+       save_protocol = ndo->ndo_protocol;
+       ndo->ndo_protocol = "MACsec";
+
+       /* we need the full MACsec header in the capture */
+       if (caplen < MACSEC_SECTAG_LEN_NOSCI) {
                nd_print_trunc(ndo);
+               ndo->ndo_protocol = save_protocol;
                return hdrlen + caplen;
        }
 
+       if (GET_U_1(sectag->tci_an) & MACSEC_TCI_SC) {
+               sectag_len = MACSEC_SECTAG_LEN_SCI;
+               if (caplen < MACSEC_SECTAG_LEN_SCI) {
+                       nd_print_trunc(ndo);
+                       ndo->ndo_protocol = save_protocol;
+                       return hdrlen + caplen;
+               }
+       } else
+               sectag_len = MACSEC_SECTAG_LEN_NOSCI;
+
        if ((GET_U_1(sectag->short_length) & ~MACSEC_SL_MASK) != 0 || 
            GET_U_1(sectag->tci_an) & MACSEC_TCI_VERSION) {
                nd_print_invalid(ndo);
+               ndo->ndo_protocol = save_protocol;
                return hdrlen + caplen;
        }
 
@@ -162,21 +144,20 @@ int macsec_print(netdissect_options *ndo, const u_char **bp,
                ND_PRINT(", ");
        }
 
-       len = ieee8021ae_sectag_len(ndo, sectag);
-
        /* Skip the MACsec header. */
-       *bp += len;
-       *hdrlenp += len;
+       *bp += sectag_len;
+       *hdrlenp += sectag_len;
 
        /* Remove it from the lengths, as it's been processed. */
-       *lengthp -= len;
-       *caplenp -= len;
+       *lengthp -= sectag_len;
+       *caplenp -= sectag_len;
 
        if ((GET_U_1(sectag->tci_an) & MACSEC_TCI_CONFID)) {
                /*
                 * The payload is encrypted.  Tell our
                 * caller it can't be dissected.
                 */
+               ndo->ndo_protocol = save_protocol;
                return 0;
        } else {
                /*
@@ -186,6 +167,7 @@ int macsec_print(netdissect_options *ndo, const u_char **bp,
                 */
                *lengthp -= MACSEC_DEFAULT_ICV_LEN;
                *caplenp -= MACSEC_DEFAULT_ICV_LEN;
+               ndo->ndo_protocol = save_protocol;
                return -1;
        }
 }