/* \summary: Extensible Authentication Protocol (EAP) printer */
-#ifdef HAVE_CONFIG_H
#include <config.h>
-#endif
#include "netdissect-stdinc.h"
+#define ND_LONGJMP_FROM_TCHECK
#include "netdissect.h"
#include "extract.h"
};
static const struct tok eap_frame_type_values[] = {
- { EAP_FRAME_TYPE_PACKET, "EAP packet" },
- { EAP_FRAME_TYPE_START, "EAPOL start" },
- { EAP_FRAME_TYPE_LOGOFF, "EAPOL logoff" },
- { EAP_FRAME_TYPE_KEY, "EAPOL key" },
- { EAP_FRAME_TYPE_ENCAP_ASF_ALERT, "Encapsulated ASF alert" },
+ { EAP_FRAME_TYPE_PACKET, "EAP packet" },
+ { EAP_FRAME_TYPE_START, "EAPOL start" },
+ { EAP_FRAME_TYPE_LOGOFF, "EAPOL logoff" },
+ { EAP_FRAME_TYPE_KEY, "EAPOL key" },
+ { EAP_FRAME_TYPE_ENCAP_ASF_ALERT, "Encapsulated ASF alert" },
{ 0, NULL}
};
#define EAP_TYPE_MD5_CHALLENGE 4
#define EAP_TYPE_OTP 5
#define EAP_TYPE_GTC 6
-#define EAP_TYPE_TLS 13 /* RFC 2716 */
+#define EAP_TYPE_TLS 13 /* RFC 5216 */
#define EAP_TYPE_SIM 18 /* RFC 4186 */
-#define EAP_TYPE_TTLS 21 /* draft-funk-eap-ttls-v0-01.txt */
+#define EAP_TYPE_TTLS 21 /* RFC 5281, draft-funk-eap-ttls-v0-01.txt */
#define EAP_TYPE_AKA 23 /* RFC 4187 */
#define EAP_TYPE_FAST 43 /* RFC 4851 */
#define EAP_TYPE_EXPANDED_TYPES 254
{ EAP_TYPE_NO_PROPOSED, "No proposed" },
{ EAP_TYPE_IDENTITY, "Identity" },
{ EAP_TYPE_NOTIFICATION, "Notification" },
- { EAP_TYPE_NAK, "Nak" },
+ { EAP_TYPE_NAK, "Nak" },
{ EAP_TYPE_MD5_CHALLENGE, "MD5-challenge" },
- { EAP_TYPE_OTP, "OTP" },
- { EAP_TYPE_GTC, "GTC" },
- { EAP_TYPE_TLS, "TLS" },
- { EAP_TYPE_SIM, "SIM" },
- { EAP_TYPE_TTLS, "TTLS" },
- { EAP_TYPE_AKA, "AKA" },
- { EAP_TYPE_FAST, "FAST" },
+ { EAP_TYPE_OTP, "OTP" },
+ { EAP_TYPE_GTC, "GTC" },
+ { EAP_TYPE_TLS, "TLS" },
+ { EAP_TYPE_SIM, "SIM" },
+ { EAP_TYPE_TTLS, "TTLS" },
+ { EAP_TYPE_AKA, "AKA" },
+ { EAP_TYPE_FAST, "FAST" },
{ EAP_TYPE_EXPANDED_TYPES, "Expanded types" },
{ EAP_TYPE_EXPERIMENTAL, "Experimental" },
{ 0, NULL}
};
-#define EAP_TLS_EXTRACT_BIT_L(x) (((x)&0x80)>>7)
+#define EAP_TLS_EXTRACT_BIT_L(x) (((x)&0x80)>>7)
-/* RFC 2716 - EAP TLS bits */
+/* RFC 5216 - EAP TLS bits */
#define EAP_TLS_FLAGS_LEN_INCLUDED (1 << 7)
#define EAP_TLS_FLAGS_MORE_FRAGMENTS (1 << 6)
#define EAP_TLS_FLAGS_START (1 << 5)
void
eap_print(netdissect_options *ndo,
const u_char *cp,
- u_int length)
+ const u_int length)
{
- const struct eap_frame_t *eap;
- const u_char *tptr;
- u_int eap_type, tlen, type, subtype;
- int count=0, len;
+ u_int type, subtype, len;
+ u_int count;
+ const char *sep;
ndo->ndo_protocol = "eap";
- tptr = cp;
- tlen = length;
- eap = (const struct eap_frame_t *)cp;
- ND_TCHECK_SIZE(eap);
- eap_type = GET_U_1(eap->type);
-
- ND_PRINT("%s (%u) v%u, len %u",
- tok2str(eap_frame_type_values, "unknown", eap_type),
- eap_type,
- GET_U_1(eap->version),
- GET_BE_U_2(eap->length));
-
- if (ndo->ndo_vflag < 1)
+ type = GET_U_1(cp);
+ len = GET_BE_U_2(cp + 2);
+ ND_ICHECK_U(len, <, 4);
+ if (len != length) {
+ /*
+ * Probably a fragment; in some cases the fragmentation might
+ * not put an EAP header on every packet, if reassembly can
+ * be done without that (e.g., fragmentation to make a message
+ * fit in multiple TLVs in a RADIUS packet).
+ */
+ ND_PRINT("EAP fragment?");
return;
-
- tptr += sizeof(struct eap_frame_t);
- tlen -= sizeof(struct eap_frame_t);
-
- switch (eap_type) {
- case EAP_FRAME_TYPE_PACKET:
- ND_TCHECK_1(tptr);
- type = GET_U_1(tptr);
- ND_TCHECK_2(tptr + 2);
- len = GET_BE_U_2(tptr + 2);
- ND_PRINT(", %s (%u), id %u, len %u",
- tok2str(eap_code_values, "unknown", type),
- type,
- GET_U_1((tptr + 1)),
- len);
-
- ND_TCHECK_LEN(tptr, len);
-
- if (type == EAP_REQUEST || type == EAP_RESPONSE) {
- /* RFC 3748 Section 4.1 */
- ND_TCHECK_1(tptr + 4);
- subtype = GET_U_1(tptr + 4);
- ND_PRINT("\n\t\t Type %s (%u)",
- tok2str(eap_type_values, "unknown", subtype),
- subtype);
-
- switch (subtype) {
+ }
+ ND_PRINT("%s (%u), id %u, len %u",
+ tok2str(eap_code_values, "unknown", type),
+ type,
+ GET_U_1((cp + 1)),
+ len);
+
+ ND_TCHECK_LEN(cp, len);
+
+ if (type == EAP_REQUEST || type == EAP_RESPONSE) {
+ /* RFC 3748 Section 4.1 */
+ ND_ICHECK_U(len, <, 5);
+ subtype = GET_U_1(cp + 4);
+ ND_PRINT("\n\t\t Type %s (%u)",
+ tok2str(eap_type_values, "unknown", subtype),
+ subtype);
+
+ switch (subtype) {
case EAP_TYPE_IDENTITY:
- if (len - 5 > 0) {
+ /* According to RFC 3748, the message is optional */
+ if (len > 5) {
ND_PRINT(", Identity: ");
- (void)nd_printzp(ndo, tptr + 5, len - 5, NULL);
+ nd_printjnp(ndo, cp + 5, len - 5);
}
break;
case EAP_TYPE_NOTIFICATION:
- if (len - 5 > 0) {
- ND_PRINT(", Notification: ");
- (void)nd_printzp(ndo, tptr + 5, len - 5, NULL);
- }
+ /* According to RFC 3748, there must be at least one octet of message */
+ ND_ICHECK_U(len, <, 6);
+ ND_PRINT(", Notification: ");
+ nd_printjnp(ndo, cp + 5, len - 5);
break;
case EAP_TYPE_NAK:
- count = 5;
-
/*
* one or more octets indicating
* the desired authentication
* type one octet per type
*/
- while (count < len) {
- ND_TCHECK_1(tptr + count);
- ND_PRINT(" %s (%u),",
- tok2str(eap_type_values, "unknown", GET_U_1((tptr + count))),
- GET_U_1(tptr + count));
- count++;
+ ND_ICHECK_U(len, <, 6);
+ sep = "";
+ for (count = 5; count < len; count++) {
+ ND_PRINT("%s %s (%u)", sep,
+ tok2str(eap_type_values, "unknown", GET_U_1((cp + count))),
+ GET_U_1(cp + count));
+ sep = ",";
}
break;
case EAP_TYPE_TTLS:
case EAP_TYPE_TLS:
- ND_TCHECK_1(tptr + 5);
+ ND_ICHECK_U(len, <, 6);
if (subtype == EAP_TYPE_TTLS)
ND_PRINT(" TTLSv%u",
- EAP_TTLS_VERSION(GET_U_1((tptr + 5))));
- ND_PRINT(" flags [%s] 0x%02x,",
- bittok2str(eap_tls_flags_values, "none", GET_U_1((tptr + 5))),
- GET_U_1(tptr + 5));
-
- if (EAP_TLS_EXTRACT_BIT_L(GET_U_1(tptr + 5))) {
- ND_TCHECK_4(tptr + 6);
- ND_PRINT(" len %u", GET_BE_U_4(tptr + 6));
+ EAP_TTLS_VERSION(GET_U_1((cp + 5))));
+ ND_PRINT(" flags [%s] 0x%02x",
+ bittok2str(eap_tls_flags_values, "none", GET_U_1((cp + 5))),
+ GET_U_1(cp + 5));
+
+ if (EAP_TLS_EXTRACT_BIT_L(GET_U_1(cp + 5))) {
+ ND_ICHECK_U(len, <, 10);
+ ND_PRINT(", len %u", GET_BE_U_4(cp + 6));
}
break;
case EAP_TYPE_FAST:
- ND_TCHECK_1(tptr + 5);
+ ND_ICHECK_U(len, <, 6);
ND_PRINT(" FASTv%u",
- EAP_TTLS_VERSION(GET_U_1((tptr + 5))));
- ND_PRINT(" flags [%s] 0x%02x,",
- bittok2str(eap_tls_flags_values, "none", GET_U_1((tptr + 5))),
- GET_U_1(tptr + 5));
-
- if (EAP_TLS_EXTRACT_BIT_L(GET_U_1(tptr + 5))) {
- ND_TCHECK_4(tptr + 6);
- ND_PRINT(" len %u", GET_BE_U_4(tptr + 6));
+ EAP_TTLS_VERSION(GET_U_1((cp + 5))));
+ ND_PRINT(" flags [%s] 0x%02x",
+ bittok2str(eap_tls_flags_values, "none", GET_U_1((cp + 5))),
+ GET_U_1(cp + 5));
+
+ if (EAP_TLS_EXTRACT_BIT_L(GET_U_1(cp + 5))) {
+ ND_ICHECK_U(len, <, 10);
+ ND_PRINT(", len %u", GET_BE_U_4(cp + 6));
}
/* FIXME - TLV attributes follow */
case EAP_TYPE_AKA:
case EAP_TYPE_SIM:
- ND_TCHECK_1(tptr + 5);
- ND_PRINT(" subtype [%s] 0x%02x,",
- tok2str(eap_aka_subtype_values, "unknown", GET_U_1((tptr + 5))),
- GET_U_1(tptr + 5));
+ ND_ICHECK_U(len, <, 6);
+ ND_PRINT(" subtype [%s] 0x%02x",
+ tok2str(eap_aka_subtype_values, "unknown", GET_U_1((cp + 5))),
+ GET_U_1(cp + 5));
/* FIXME - TLV attributes follow */
break;
case EAP_TYPE_EXPERIMENTAL:
default:
break;
- }
}
- break;
+ }
+ return;
+invalid:
+ nd_print_invalid(ndo);
+}
+
+void
+eapol_print(netdissect_options *ndo,
+ const u_char *cp)
+{
+ const struct eap_frame_t *eap;
+ u_int eap_type, eap_len;
+
+ ndo->ndo_protocol = "eap";
+ eap = (const struct eap_frame_t *)cp;
+ eap_type = GET_U_1(eap->type);
+
+ ND_PRINT("%s (%u) v%u, len %u",
+ tok2str(eap_frame_type_values, "unknown", eap_type),
+ eap_type,
+ GET_U_1(eap->version),
+ GET_BE_U_2(eap->length));
+ if (ndo->ndo_vflag < 1)
+ return;
+
+ cp += sizeof(struct eap_frame_t);
+ eap_len = GET_BE_U_2(eap->length);
+
+ switch (eap_type) {
+ case EAP_FRAME_TYPE_PACKET:
+ if (eap_len == 0)
+ goto invalid;
+ ND_PRINT(", ");
+ eap_print(ndo, cp, eap_len);
+ break;
case EAP_FRAME_TYPE_LOGOFF:
case EAP_FRAME_TYPE_ENCAP_ASF_ALERT:
default:
}
return;
- trunc:
- nd_print_trunc(ndo);
+invalid:
+ nd_print_invalid(ndo);
}
projects / tcpdump / blobdiff