/* * Copyright (C) 2005-2010 Martin Willi * Copyright (C) 2005 Jan Hutter * Hochschule fuer Technik Rapperswil * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the * Free Software Foundation; either version 2 of the License, or (at your * option) any later version. See . * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * for more details. */ #include #include "eap_payload.h" #include typedef struct private_eap_payload_t private_eap_payload_t; /** * Private data of an eap_payload_t object. * */ struct private_eap_payload_t { /** * Public eap_payload_t interface. */ eap_payload_t public; /** * Next payload type. */ u_int8_t next_payload; /** * Critical flag. */ bool critical; /** * Reserved bits */ bool reserved[7]; /** * Length of this payload. */ u_int16_t payload_length; /** * EAP message data, if available */ chunk_t data; }; /** * Encoding rules to parse or generate a EAP payload. * * The defined offsets are the positions in a object of type * private_eap_payload_t. * */ static encoding_rule_t eap_payload_encodings[] = { /* 1 Byte next payload type, stored in the field next_payload */ { U_INT_8, offsetof(private_eap_payload_t, next_payload) }, /* the critical bit */ { FLAG, offsetof(private_eap_payload_t, critical) }, /* 7 Bit reserved bits, nowhere stored */ { RESERVED_BIT, offsetof(private_eap_payload_t, reserved[0]) }, { RESERVED_BIT, offsetof(private_eap_payload_t, reserved[1]) }, { RESERVED_BIT, offsetof(private_eap_payload_t, reserved[2]) }, { RESERVED_BIT, offsetof(private_eap_payload_t, reserved[3]) }, { RESERVED_BIT, offsetof(private_eap_payload_t, reserved[4]) }, { RESERVED_BIT, offsetof(private_eap_payload_t, reserved[5]) }, { RESERVED_BIT, offsetof(private_eap_payload_t, reserved[6]) }, /* Length of the whole payload*/ { PAYLOAD_LENGTH, offsetof(private_eap_payload_t, payload_length) }, /* chunt to data, starting at "code" */ { EAP_DATA, offsetof(private_eap_payload_t, data) }, }; /* 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ! Next Payload !C! RESERVED ! Payload Length ! +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ! Code ! Identifier ! Length ! +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ! Type ! Type_Data... +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- */ METHOD(payload_t, verify, status_t, private_eap_payload_t *this) { u_int16_t length; u_int8_t code; if (this->data.len < 4) { DBG1(DBG_ENC, "EAP payloads EAP message too short (%d)", this->data.len); return FAILED; } length = untoh16(this->data.ptr + 2); if (this->data.len != length) { DBG1(DBG_ENC, "EAP payload length (%d) does not match contained " "message length (%d)", this->data.len, length); return FAILED; } code = this->data.ptr[0]; switch (code) { case EAP_REQUEST: case EAP_RESPONSE: { if (this->data.len < 4) { DBG1(DBG_ENC, "EAP Request/Response does not have any data"); return FAILED; } break; } case EAP_SUCCESS: case EAP_FAILURE: { if (this->data.len != 4) { DBG1(DBG_ENC, "EAP Success/Failure has data"); return FAILED; } break; } default: return FAILED; } return SUCCESS; } METHOD(payload_t, get_encoding_rules, void, private_eap_payload_t *this, encoding_rule_t **rules, size_t *rule_count) { *rules = eap_payload_encodings; *rule_count = sizeof(eap_payload_encodings) / sizeof(encoding_rule_t); } METHOD(payload_t, get_payload_type, payload_type_t, private_eap_payload_t *this) { return EXTENSIBLE_AUTHENTICATION; } METHOD(payload_t, get_next_type, payload_type_t, private_eap_payload_t *this) { return (this->next_payload); } METHOD(payload_t, set_next_type, void, private_eap_payload_t *this, payload_type_t type) { this->next_payload = type; } METHOD(payload_t, get_length, size_t, private_eap_payload_t *this) { return this->payload_length; } METHOD(eap_payload_t, get_data, chunk_t, private_eap_payload_t *this) { return this->data; } METHOD(eap_payload_t, set_data, void, private_eap_payload_t *this, chunk_t data) { free(this->data.ptr); this->data = chunk_clone(data); this->payload_length = this->data.len + 4; } METHOD(eap_payload_t, get_code, eap_code_t, private_eap_payload_t *this) { if (this->data.len > 0) { return this->data.ptr[0]; } /* should not happen, as it is verified */ return 0; } METHOD(eap_payload_t, get_identifier, u_int8_t, private_eap_payload_t *this) { if (this->data.len > 1) { return this->data.ptr[1]; } /* should not happen, as it is verified */ return 0; } METHOD(eap_payload_t, get_type, eap_type_t, private_eap_payload_t *this, u_int32_t *vendor) { eap_type_t type; *vendor = 0; if (this->data.len > 4) { type = this->data.ptr[4]; if (type != EAP_EXPANDED) { return type; } if (this->data.len >= 12) { *vendor = untoh32(this->data.ptr + 4) & 0x00FFFFFF; return untoh32(this->data.ptr + 8); } } return 0; } METHOD2(payload_t, eap_payload_t, destroy, void, private_eap_payload_t *this) { chunk_free(&this->data); free(this); } /* * Described in header */ eap_payload_t *eap_payload_create() { private_eap_payload_t *this; INIT(this, .public = { .payload_interface = { .verify = _verify, .get_encoding_rules = _get_encoding_rules, .get_length = _get_length, .get_next_type = _get_next_type, .set_next_type = _set_next_type, .get_type = _get_payload_type, .destroy = _destroy, }, .get_data = _get_data, .set_data = _set_data, .get_code = _get_code, .get_identifier = _get_identifier, .get_type = _get_type, .destroy = _destroy, }, .next_payload = NO_PAYLOAD, .payload_length = EAP_PAYLOAD_HEADER_LENGTH, ); return &this->public; } /* * Described in header */ eap_payload_t *eap_payload_create_data(chunk_t data) { eap_payload_t *this = eap_payload_create(); this->set_data(this, data); return this; } /* * Described in header */ eap_payload_t *eap_payload_create_code(eap_code_t code, u_int8_t identifier) { chunk_t data; data = chunk_from_chars(code, identifier, 0, 0); htoun16(data.ptr + 2, data.len); return eap_payload_create_data(data); } /* * Described in header */ eap_payload_t *eap_payload_create_nak(u_int8_t identifier) { chunk_t data; data = chunk_from_chars(EAP_RESPONSE, identifier, 0, 0, EAP_NAK); htoun16(data.ptr + 2, data.len); return eap_payload_create_data(data); }