ieee_802_11.h

00001 /*
00002  * Copyright (c) 2016-2018, Arm Limited and affiliates.
00003  * SPDX-License-Identifier: Apache-2.0
00004  *
00005  * Licensed under the Apache License, Version 2.0 (the "License");
00006  * you may not use this file except in compliance with the License.
00007  * You may obtain a copy of the License at
00008  *
00009  *     http://www.apache.org/licenses/LICENSE-2.0
00010  *
00011  * Unless required by applicable law or agreed to in writing, software
00012  * distributed under the License is distributed on an "AS IS" BASIS,
00013  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00014  * See the License for the specific language governing permissions and
00015  * limitations under the License.
00016  */
00017 
00018 #ifndef IEEE_802_11_
00019 #define IEEE_802_11_
00020 
00021 typedef struct {
00022     const uint8_t *key;   /**< Key string */
00023     uint8_t *string;      /**< Data string (A string + Y + B string + X) */
00024     uint16_t bits;        /**< Number of PRF bits */
00025     uint16_t key_len;     /**< Key string length */
00026     uint16_t a_len;       /**< A string length */
00027     uint16_t b_len;       /**< B string length */
00028 } ieee_802_11_prf_t;
00029 
00030 /*
00031     From IEEE 802.11 chapter 11.6.1.2 PRF:
00032 
00033     In the following, K is a key; A is a unique label for each different purpose
00034     of the PRF; B is a variable-length string; Y is a single octet containing 0;
00035     X is a single octet containing the loop parameter i; and || denotes concatenation:
00036 
00037     H-SHA-1(K, A, B, X) ← HMAC-SHA-1(K, A || Y || B || X)
00038 
00039     PRF(K, A, B, Len)
00040         for i ← 0 to (Len+159)/160 do
00041             R ← R || H-SHA-1(K, A, B, i)
00042         return L(R, 0, Len)
00043 
00044     PRF-128(K, A, B) = PRF(K, A, B, 128)
00045     PRF-192(K, A, B) = PRF(K, A, B, 192)
00046     PRF-256(K, A, B) = PRF(K, A, B, 256)
00047     PRF-384(K, A, B) = PRF(K, A, B, 384)
00048     PRF-512(K, A, B) = PRF(K, A, B, 512)
00049 */
00050 
00051 /**
00052  * \brief Setup IEEE 802.11 PRF
00053  *
00054  *  Update is made based on failed and successful message sending
00055  *  attempts for a message.
00056  *
00057  * \param prf pointer to PRF data
00058  * \param bits number of bits
00059  * \param a_len A string length
00060  * \param b_len B string length
00061  *
00062  * \return length of the combined string that is input parameter for further functions
00063  *         (this is length of the A string + Y + B string + X)
00064  */
00065 uint16_t ieee_802_11_prf_setup(ieee_802_11_prf_t *prf, uint16_t bits, uint16_t a_len, uint16_t b_len);
00066 
00067 /**
00068  * \brief Get A string pointer
00069  *
00070  *  Get a pointer to A string start that is used to write A string contents
00071  *
00072  * \param prf pointer to PRF data
00073  * \param string pointer to input string
00074  *
00075  * \return pointer to A string part of the input string
00076  */
00077 uint8_t *ieee_802_11_prf_get_a_string(ieee_802_11_prf_t *prf, uint8_t *string);
00078 
00079 /**
00080  * \brief Get B string pointer
00081  *
00082  *  Get a pointer to B string start that is used to write B string contents
00083  *
00084  * \param prf pointer to PRF data
00085  * \param string pointer to input string
00086  *
00087  * \return pointer to B string part of the input string
00088  */
00089 uint8_t *ieee_802_11_prf_get_b_string(ieee_802_11_prf_t *prf, uint8_t *string);
00090 
00091 /**
00092  * \brief Start PRF process
00093  *
00094  *  Start PRF process
00095  *
00096  * \param prf pointer to PRF data
00097  * \param key key
00098  * \param key_len key length
00099  *
00100  * \return length of the return string
00101  */
00102 uint16_t ieee_802_11_prf_starts(ieee_802_11_prf_t *prf, const uint8_t *key, uint16_t key_len);
00103 
00104 /**
00105  * \brief Update PRF process
00106  *
00107  *  Update PRF process
00108  *
00109  * \param prf pointer to PRF data
00110  * \param string pointer to input string
00111  *
00112  */
00113 void ieee_802_11_prf_update(ieee_802_11_prf_t *prf, uint8_t *string);
00114 
00115 /**
00116  * \brief Finish PRF process
00117  *
00118  *  Finish PRF process
00119  *
00120  * \param prf pointer to PRF data
00121  * \param result pointer to result string
00122  *
00123  * \return < 0 failure
00124  * \return >= 0 success
00125  *
00126  */
00127 int8_t ieee_802_11_prf_finish(ieee_802_11_prf_t *prf, uint8_t *result);
00128 
00129 #endif /* IEEE_802_11_*/