130 lines
2.8 KiB
C
130 lines
2.8 KiB
C
/*
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*
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* Wireless daemon for Linux
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*
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* Copyright (C) 2014 Intel Corporation. All rights reserved.
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with this library; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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*
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*/
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#ifdef HAVE_CONFIG_H
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#include <config.h>
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#endif
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#include <ell/ell.h>
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#include "ie.h"
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#include "mpdu.h"
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static bool validate_mgmt_header(const struct mpdu *mpdu, int len, int *offset)
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{
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/* Duration + Address1 + Address 2 + Address 3 + SeqCntrl */
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if (len < *offset + 22)
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return false;
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*offset += 22;
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if (!mpdu->fc.order)
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return true;
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if (len < *offset + 4)
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return false;
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*offset += 4;
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return true;
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}
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static bool validate_authentication_mgmt_mpdu(const struct mpdu *mpdu,
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int len, int *offset)
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{
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if (len < *offset + 6)
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return false;
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switch (mpdu->auth.algorithm) {
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case MPDU_AUTH_ALGO_OPEN_SYSTEM:
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return *offset <= len;
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case MPDU_AUTH_ALGO_SHARED_KEY:
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if (mpdu->auth.transaction_sequence < 2 ||
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mpdu->auth.transaction_sequence > 3)
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return *offset == len;
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if (len < *offset + 2)
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return false;
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*offset += 2;
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if (mpdu->auth.shared_key_23.element_id !=
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IE_TYPE_CHALLENGE_TEXT)
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return false;
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*offset += mpdu->auth.shared_key_23.challenge_text_len;
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return *offset <= len;
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default:
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return false;
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}
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return false;
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}
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static bool validate_deauthentication_mgmt_mpdu(const struct mpdu *mpdu,
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int len, int *offset)
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{
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*offset += 2;
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return *offset <= len;
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}
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static bool validate_mgmt_mpdu(const struct mpdu *mpdu, int len, int *offset)
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{
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if (!validate_mgmt_header(mpdu, len, offset))
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return false;
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switch (mpdu->fc.subtype) {
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case MPDU_MANAGEMENT_SUBTYPE_AUTHENTICATION:
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return validate_authentication_mgmt_mpdu(mpdu, len, offset);
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case MPDU_MANAGEMENT_SUBTYPE_DEAUTHENTICATION:
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return validate_deauthentication_mgmt_mpdu(mpdu, len, offset);
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default:
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return false;
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}
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return true;
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}
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bool mpdu_validate(const unsigned char *frame, int len)
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{
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struct mpdu *mpdu;
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int offset;
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if (!frame)
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return false;
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if (len < 2)
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return false;
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offset = 2;
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mpdu = (struct mpdu *) frame;
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switch (mpdu->fc.type) {
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case MPDU_TYPE_MANAGEMENT:
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return validate_mgmt_mpdu(mpdu, len, &offset);
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default:
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return false;
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}
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return true;
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}
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