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authorSichen Zhao <1473996754@qq.com>2017-08-01 20:43:41 +0800
committerSebastian Huber <sebastian.huber@embedded-brains.de>2017-11-10 13:33:02 +0100
commit9c9d11b481ce0dcdfa9c69e6781cc15435cfb043 (patch)
tree3d0e6678afcdbb17d35606398f220fba66dcfa7b /freebsd/contrib/wpa/src/crypto/sha256-prf.c
parentFix build for non-FDT platforms (diff)
downloadrtems-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.c102
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));
+}