X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/80c07e2a8b50dc71033d6a88e3236298be8e5b0b..HEAD:/print-macsec.c

diff --git a/print-macsec.c b/print-macsec.c
index 892f2c33..5fca3922 100644
--- a/print-macsec.c
+++ b/print-macsec.c
@@ -21,17 +21,12 @@
 
 /* \summary: MACsec printer */
 
-#ifdef HAVE_CONFIG_H
-#include "config.h"
-#endif
+#include <config.h>
 
-#include <netdissect-stdinc.h>
-
-#include <string.h>
+#include "netdissect-stdinc.h"
 
 #include "netdissect.h"
 #include "addrtoname.h"
-#include "ethertype.h"
 #include "extract.h"
 
 #define MACSEC_DEFAULT_ICV_LEN 16
@@ -89,9 +84,31 @@ static const struct tok macsec_flag_values[] = {
 	{ 0, NULL }
 };
 
+static void
+macsec_print_header(netdissect_options *ndo,
+		    const struct macsec_sectag *sectag,
+		    u_int short_length)
+{
+	ND_PRINT("an %u, pn %u, flags %s",
+		 GET_U_1(sectag->tci_an) & MACSEC_AN_MASK,
+		 GET_BE_U_4(sectag->packet_number),
+		 bittok2str_nosep(macsec_flag_values, "none",
+				  GET_U_1(sectag->tci_an) & MACSEC_TCI_FLAGS));
+
+	if (short_length != 0)
+		ND_PRINT(", sl %u", short_length);
+
+	if (GET_U_1(sectag->tci_an) & MACSEC_TCI_SC)
+		ND_PRINT(", sci " SCI_FMT, GET_BE_U_8(sectag->secure_channel_id));
+
+	ND_PRINT(", ");
+}
+
 /* 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)
+int
+macsec_print(netdissect_options *ndo, const u_char **bp,
+	     u_int *lengthp, u_int *caplenp, u_int *hdrlenp,
+	     const struct lladdr_info *src, const struct lladdr_info *dst)
 {
 	const char *save_protocol;
 	const u_char *p = *bp;
@@ -103,7 +120,7 @@ int macsec_print(netdissect_options *ndo, const u_char **bp,
 	u_int short_length;
 
 	save_protocol = ndo->ndo_protocol;
-	ndo->ndo_protocol = "MACsec";
+	ndo->ndo_protocol = "macsec";
 
 	/* we need the full MACsec header in the capture */
 	if (caplen < MACSEC_SECTAG_LEN_NOSCI) {
@@ -132,7 +149,7 @@ int macsec_print(netdissect_options *ndo, const u_char **bp,
 	} else
 		sectag_len = MACSEC_SECTAG_LEN_NOSCI;
 
-	if ((GET_U_1(sectag->short_length) & ~MACSEC_SL_MASK) != 0 || 
+	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;
@@ -140,21 +157,8 @@ int macsec_print(netdissect_options *ndo, const u_char **bp,
 	}
 
 	short_length = GET_U_1(sectag->short_length) & MACSEC_SL_MASK;
-	if (ndo->ndo_eflag) {
-		ND_PRINT("an %u, pn %u, flags %s",
-			 GET_U_1(sectag->tci_an) & MACSEC_AN_MASK,
-			 GET_BE_U_4(sectag->packet_number),
-			 bittok2str_nosep(macsec_flag_values, "none",
-					  GET_U_1(sectag->tci_an) & MACSEC_TCI_FLAGS));
-
-		if (short_length != 0)
-			ND_PRINT(", sl %u", short_length);
-
-		if (GET_U_1(sectag->tci_an) & MACSEC_TCI_SC)
-			ND_PRINT(", sci " SCI_FMT, GET_BE_U_8(sectag->secure_channel_id));
-		
-		ND_PRINT(", ");
-	}
+	if (ndo->ndo_eflag)
+		macsec_print_header(ndo, sectag, short_length);
 
 	/* Skip the MACsec header. */
 	*bp += sectag_len;
@@ -166,8 +170,30 @@ int macsec_print(netdissect_options *ndo, const u_char **bp,
 
 	if ((GET_U_1(sectag->tci_an) & MACSEC_TCI_CONFID)) {
 		/*
-		 * The payload is encrypted.  Tell our
-		 * caller it can't be dissected.
+		 * The payload is encrypted.  Print link-layer
+		 * information, if it hasn't already been printed.
+		 */
+		if (!ndo->ndo_eflag) {
+			/*
+			 * Nobody printed the link-layer addresses,
+			 * so print them, if we have any.
+			 */
+			if (src != NULL && dst != NULL) {
+				ND_PRINT("%s > %s ",
+					(src->addr_string)(ndo, src->addr),
+					(dst->addr_string)(ndo, dst->addr));
+			}
+
+			ND_PRINT("802.1AE MACsec, ");
+
+			/*
+			 * Print the MACsec header.
+			 */
+			macsec_print_header(ndo, sectag, short_length);
+		}
+
+		/*
+		 * Tell our caller it can't be dissected.
 		 */
 		ndo->ndo_protocol = save_protocol;
 		return 0;
@@ -190,6 +216,13 @@ int macsec_print(netdissect_options *ndo, const u_char **bp,
 	}
 	*lengthp -= MACSEC_DEFAULT_ICV_LEN;
 	*caplenp -= MACSEC_DEFAULT_ICV_LEN;
+	/*
+	 * Update the snapend thus the ICV field is not in the payload for
+	 * the caller.
+	 * The ICV (Integrity Check Value) is at the end of the frame, after
+	 * the secure data.
+	 */
+	ndo->ndo_snapend -= MACSEC_DEFAULT_ICV_LEN;
 
 	/*
 	 * If the SL field is non-zero, then it's the length of the
@@ -216,7 +249,7 @@ int macsec_print(netdissect_options *ndo, const u_char **bp,
 		if (*caplenp > short_length)
 			*caplenp = short_length;
 	}
-		
+
 	ndo->ndo_protocol = save_protocol;
 	return -1;
 }