| /* |
| * Copyright (c) 2004 - Michael Richardson <mcr@xelerance.com> |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that: (1) source code distributions |
| * retain the above copyright notice and this paragraph in its entirety, (2) |
| * distributions including binary code include the above copyright notice and |
| * this paragraph in its entirety in the documentation or other materials |
| * provided with the distribution, and (3) all advertising materials mentioning |
| * features or use of this software display the following acknowledgement: |
| * ``This product includes software developed by the University of California, |
| * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of |
| * the University nor the names of its contributors may be used to endorse |
| * or promote products derived from this software without specific prior |
| * written permission. |
| * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED |
| * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF |
| * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. |
| */ |
| |
| /* \summary: Extensible Authentication Protocol (EAP) printer */ |
| |
| #ifdef HAVE_CONFIG_H |
| #include <config.h> |
| #endif |
| |
| #include "netdissect-stdinc.h" |
| |
| #include "netdissect.h" |
| #include "extract.h" |
| |
| #define EAP_FRAME_TYPE_PACKET 0 |
| #define EAP_FRAME_TYPE_START 1 |
| #define EAP_FRAME_TYPE_LOGOFF 2 |
| #define EAP_FRAME_TYPE_KEY 3 |
| #define EAP_FRAME_TYPE_ENCAP_ASF_ALERT 4 |
| |
| struct eap_frame_t { |
| nd_uint8_t version; |
| nd_uint8_t type; |
| nd_uint16_t length; |
| }; |
| |
| 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" }, |
| { 0, NULL} |
| }; |
| |
| /* RFC 3748 */ |
| struct eap_packet_t { |
| nd_uint8_t code; |
| nd_uint8_t id; |
| nd_uint16_t length; |
| }; |
| |
| #define EAP_REQUEST 1 |
| #define EAP_RESPONSE 2 |
| #define EAP_SUCCESS 3 |
| #define EAP_FAILURE 4 |
| |
| static const struct tok eap_code_values[] = { |
| { EAP_REQUEST, "Request" }, |
| { EAP_RESPONSE, "Response" }, |
| { EAP_SUCCESS, "Success" }, |
| { EAP_FAILURE, "Failure" }, |
| { 0, NULL} |
| }; |
| |
| #define EAP_TYPE_NO_PROPOSED 0 |
| #define EAP_TYPE_IDENTITY 1 |
| #define EAP_TYPE_NOTIFICATION 2 |
| #define EAP_TYPE_NAK 3 |
| #define EAP_TYPE_MD5_CHALLENGE 4 |
| #define EAP_TYPE_OTP 5 |
| #define EAP_TYPE_GTC 6 |
| #define EAP_TYPE_TLS 13 /* RFC 5216 */ |
| #define EAP_TYPE_SIM 18 /* RFC 4186 */ |
| #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 |
| #define EAP_TYPE_EXPERIMENTAL 255 |
| |
| static const struct tok eap_type_values[] = { |
| { EAP_TYPE_NO_PROPOSED, "No proposed" }, |
| { EAP_TYPE_IDENTITY, "Identity" }, |
| { EAP_TYPE_NOTIFICATION, "Notification" }, |
| { 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_EXPANDED_TYPES, "Expanded types" }, |
| { EAP_TYPE_EXPERIMENTAL, "Experimental" }, |
| { 0, NULL} |
| }; |
| |
| #define EAP_TLS_EXTRACT_BIT_L(x) (((x)&0x80)>>7) |
| |
| /* 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) |
| |
| static const struct tok eap_tls_flags_values[] = { |
| { EAP_TLS_FLAGS_LEN_INCLUDED, "L bit" }, |
| { EAP_TLS_FLAGS_MORE_FRAGMENTS, "More fragments bit"}, |
| { EAP_TLS_FLAGS_START, "Start bit"}, |
| { 0, NULL} |
| }; |
| |
| #define EAP_TTLS_VERSION(x) ((x)&0x07) |
| |
| /* EAP-AKA and EAP-SIM - RFC 4187 */ |
| #define EAP_AKA_CHALLENGE 1 |
| #define EAP_AKA_AUTH_REJECT 2 |
| #define EAP_AKA_SYNC_FAILURE 4 |
| #define EAP_AKA_IDENTITY 5 |
| #define EAP_SIM_START 10 |
| #define EAP_SIM_CHALLENGE 11 |
| #define EAP_AKA_NOTIFICATION 12 |
| #define EAP_AKA_REAUTH 13 |
| #define EAP_AKA_CLIENT_ERROR 14 |
| |
| static const struct tok eap_aka_subtype_values[] = { |
| { EAP_AKA_CHALLENGE, "Challenge" }, |
| { EAP_AKA_AUTH_REJECT, "Auth reject" }, |
| { EAP_AKA_SYNC_FAILURE, "Sync failure" }, |
| { EAP_AKA_IDENTITY, "Identity" }, |
| { EAP_SIM_START, "Start" }, |
| { EAP_SIM_CHALLENGE, "Challenge" }, |
| { EAP_AKA_NOTIFICATION, "Notification" }, |
| { EAP_AKA_REAUTH, "Reauth" }, |
| { EAP_AKA_CLIENT_ERROR, "Client error" }, |
| { 0, NULL} |
| }; |
| |
| /* |
| * Print EAP requests / responses |
| */ |
| void |
| eap_print(netdissect_options *ndo, |
| const u_char *cp, |
| u_int length) |
| { |
| u_int type, subtype, len; |
| u_int count; |
| const char *sep; |
| |
| type = GET_U_1(cp); |
| len = GET_BE_U_2(cp + 2); |
| 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; |
| } |
| ND_PRINT("%s (%u), id %u, len %u", |
| tok2str(eap_code_values, "unknown", type), |
| type, |
| GET_U_1((cp + 1)), |
| len); |
| if (len < 4) { |
| ND_PRINT(" (too short for EAP header)"); |
| return; |
| } |
| |
| ND_TCHECK_LEN(cp, len); |
| |
| if (type == EAP_REQUEST || type == EAP_RESPONSE) { |
| /* RFC 3748 Section 4.1 */ |
| if (len < 5) { |
| ND_PRINT(" (too short for EAP request/response)"); |
| return; |
| } |
| 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: |
| /* According to RFC 3748, the message is optional */ |
| if (len > 5) { |
| ND_PRINT(", Identity: "); |
| nd_printjnp(ndo, cp + 5, len - 5); |
| } |
| break; |
| |
| case EAP_TYPE_NOTIFICATION: |
| /* According to RFC 3748, there must be at least one octet of message */ |
| if (len < 6) { |
| ND_PRINT(" (too short for EAP Notification request/response)"); |
| return; |
| } |
| ND_PRINT(", Notification: "); |
| nd_printjnp(ndo, cp + 5, len - 5); |
| break; |
| |
| case EAP_TYPE_NAK: |
| /* |
| * one or more octets indicating |
| * the desired authentication |
| * type one octet per type |
| */ |
| if (len < 6) { |
| ND_PRINT(" (too short for EAP Legacy NAK request/response)"); |
| return; |
| } |
| 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: |
| if (len < 6) { |
| ND_PRINT(" (too short for EAP TLS/TTLS request/response)"); |
| return; |
| } |
| if (subtype == EAP_TYPE_TTLS) |
| ND_PRINT(" TTLSv%u", |
| 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))) { |
| if (len < 10) { |
| ND_PRINT(" (too short for EAP TLS/TTLS request/response with length)"); |
| return; |
| } |
| ND_PRINT(", len %u", GET_BE_U_4(cp + 6)); |
| } |
| break; |
| |
| case EAP_TYPE_FAST: |
| if (len < 6) { |
| ND_PRINT(" (too short for EAP FAST request/response)"); |
| return; |
| } |
| ND_PRINT(" FASTv%u", |
| 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))) { |
| if (len < 10) { |
| ND_PRINT(" (too short for EAP FAST request/response with length)"); |
| return; |
| } |
| ND_PRINT(", len %u", GET_BE_U_4(cp + 6)); |
| } |
| |
| /* FIXME - TLV attributes follow */ |
| break; |
| |
| case EAP_TYPE_AKA: |
| case EAP_TYPE_SIM: |
| if (len < 6) { |
| ND_PRINT(" (too short for EAP SIM/AKA request/response)"); |
| return; |
| } |
| 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_MD5_CHALLENGE: |
| case EAP_TYPE_OTP: |
| case EAP_TYPE_GTC: |
| case EAP_TYPE_EXPANDED_TYPES: |
| case EAP_TYPE_EXPERIMENTAL: |
| default: |
| break; |
| } |
| } |
| return; |
| trunc: |
| nd_print_trunc(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; |
| 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) |
| 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 trunc; |
| ND_PRINT(", "); |
| eap_print(ndo, cp, eap_len); |
| return; |
| case EAP_FRAME_TYPE_LOGOFF: |
| case EAP_FRAME_TYPE_ENCAP_ASF_ALERT: |
| default: |
| break; |
| } |
| return; |
| |
| trunc: |
| nd_print_trunc(ndo); |
| } |
