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author | Sichen Zhao <1473996754@qq.com> | 2017-08-01 20:43:41 +0800 |
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committer | Sebastian Huber <sebastian.huber@embedded-brains.de> | 2017-11-10 13:33:02 +0100 |
commit | 9c9d11b481ce0dcdfa9c69e6781cc15435cfb043 (patch) | |
tree | 3d0e6678afcdbb17d35606398f220fba66dcfa7b /freebsd/contrib/wpa/src/crypto/sha256-prf.c | |
parent | Fix build for non-FDT platforms (diff) | |
download | rtems-libbsd-9c9d11b481ce0dcdfa9c69e6781cc15435cfb043.tar.bz2 |
Import wpa from FreeBSD
Diffstat (limited to 'freebsd/contrib/wpa/src/crypto/sha256-prf.c')
-rw-r--r-- | freebsd/contrib/wpa/src/crypto/sha256-prf.c | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/freebsd/contrib/wpa/src/crypto/sha256-prf.c b/freebsd/contrib/wpa/src/crypto/sha256-prf.c new file mode 100644 index 00000000..76496214 --- /dev/null +++ b/freebsd/contrib/wpa/src/crypto/sha256-prf.c @@ -0,0 +1,102 @@ +#include <machine/rtems-bsd-user-space.h> + +/* + * SHA256-based PRF (IEEE 802.11r) + * Copyright (c) 2003-2013, Jouni Malinen <j@w1.fi> + * + * This software may be distributed under the terms of the BSD license. + * See README for more details. + */ + +#include "includes.h" + +#include "common.h" +#include "sha256.h" +#include "crypto.h" + + +/** + * sha256_prf - SHA256-based Pseudo-Random Function (IEEE 802.11r, 8.5.1.5.2) + * @key: Key for PRF + * @key_len: Length of the key in bytes + * @label: A unique label for each purpose of the PRF + * @data: Extra data to bind into the key + * @data_len: Length of the data + * @buf: Buffer for the generated pseudo-random key + * @buf_len: Number of bytes of key to generate + * + * This function is used to derive new, cryptographically separate keys from a + * given key. + */ +void sha256_prf(const u8 *key, size_t key_len, const char *label, + const u8 *data, size_t data_len, u8 *buf, size_t buf_len) +{ + sha256_prf_bits(key, key_len, label, data, data_len, buf, buf_len * 8); +} + + +/** + * sha256_prf_bits - IEEE Std 802.11-2012, 11.6.1.7.2 Key derivation function + * @key: Key for KDF + * @key_len: Length of the key in bytes + * @label: A unique label for each purpose of the PRF + * @data: Extra data to bind into the key + * @data_len: Length of the data + * @buf: Buffer for the generated pseudo-random key + * @buf_len: Number of bits of key to generate + * + * This function is used to derive new, cryptographically separate keys from a + * given key. If the requested buf_len is not divisible by eight, the least + * significant 1-7 bits of the last octet in the output are not part of the + * requested output. + */ +void sha256_prf_bits(const u8 *key, size_t key_len, const char *label, + const u8 *data, size_t data_len, u8 *buf, + size_t buf_len_bits) +{ + u16 counter = 1; + size_t pos, plen; + u8 hash[SHA256_MAC_LEN]; + const u8 *addr[4]; + size_t len[4]; + u8 counter_le[2], length_le[2]; + size_t buf_len = (buf_len_bits + 7) / 8; + + addr[0] = counter_le; + len[0] = 2; + addr[1] = (u8 *) label; + len[1] = os_strlen(label); + addr[2] = data; + len[2] = data_len; + addr[3] = length_le; + len[3] = sizeof(length_le); + + WPA_PUT_LE16(length_le, buf_len_bits); + pos = 0; + while (pos < buf_len) { + plen = buf_len - pos; + WPA_PUT_LE16(counter_le, counter); + if (plen >= SHA256_MAC_LEN) { + hmac_sha256_vector(key, key_len, 4, addr, len, + &buf[pos]); + pos += SHA256_MAC_LEN; + } else { + hmac_sha256_vector(key, key_len, 4, addr, len, hash); + os_memcpy(&buf[pos], hash, plen); + pos += plen; + break; + } + counter++; + } + + /* + * Mask out unused bits in the last octet if it does not use all the + * bits. + */ + if (buf_len_bits % 8) { + u8 mask = 0xff << (8 - buf_len_bits % 8); + buf[pos - 1] &= mask; + } + + os_memset(hash, 0, sizeof(hash)); +} |