From ab637dcb37057f433932ecc8d45e129cd2d14170 Mon Sep 17 00:00:00 2001 From: Jouni Malinen Date: Thu, 16 Aug 2012 22:24:11 +0300 Subject: [PATCH] Move SHA256-based PRF function into a separate C file This makes it easier to conditionally build in SHA256 functions based on which TLS/crypto library is used. Signed-hostap: Jouni Malinen --- hostapd/Android.mk | 1 + hostapd/Makefile | 1 + src/crypto/sha256-prf.c | 64 +++++++++++++++++++++++++++++++++++++++ src/crypto/sha256.c | 51 ------------------------------- wpa_supplicant/Android.mk | 1 + wpa_supplicant/Makefile | 1 + 6 files changed, 68 insertions(+), 51 deletions(-) create mode 100644 src/crypto/sha256-prf.c diff --git a/hostapd/Android.mk b/hostapd/Android.mk index 5a0136b17..23d86f093 100644 --- a/hostapd/Android.mk +++ b/hostapd/Android.mk @@ -721,6 +721,7 @@ endif ifdef NEED_SHA256 OBJS += src/crypto/sha256.c +OBJS += src/crypto/sha256-prf.c ifdef CONFIG_INTERNAL_SHA256 OBJS += src/crypto/sha256-internal.c endif diff --git a/hostapd/Makefile b/hostapd/Makefile index 120eca638..c2f0530b3 100644 --- a/hostapd/Makefile +++ b/hostapd/Makefile @@ -713,6 +713,7 @@ endif ifdef NEED_SHA256 CFLAGS += -DCONFIG_SHA256 OBJS += ../src/crypto/sha256.o +OBJS += ../src/crypto/sha256-prf.o ifdef CONFIG_INTERNAL_SHA256 OBJS += ../src/crypto/sha256-internal.o endif diff --git a/src/crypto/sha256-prf.c b/src/crypto/sha256-prf.c new file mode 100644 index 000000000..0da6d130a --- /dev/null +++ b/src/crypto/sha256-prf.c @@ -0,0 +1,64 @@ +/* + * SHA256-based PRF (IEEE 802.11r) + * Copyright (c) 2003-2007, Jouni Malinen + * + * 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) +{ + 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]; + + 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 * 8); + 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); + break; + } + counter++; + } +} diff --git a/src/crypto/sha256.c b/src/crypto/sha256.c index 5c09ed197..493acda87 100644 --- a/src/crypto/sha256.c +++ b/src/crypto/sha256.c @@ -98,54 +98,3 @@ void hmac_sha256(const u8 *key, size_t key_len, const u8 *data, { hmac_sha256_vector(key, key_len, 1, &data, &data_len, mac); } - - -/** - * 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) -{ - 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]; - - 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 * 8); - 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); - break; - } - counter++; - } -} diff --git a/wpa_supplicant/Android.mk b/wpa_supplicant/Android.mk index 9b51f0773..d0254ab9f 100644 --- a/wpa_supplicant/Android.mk +++ b/wpa_supplicant/Android.mk @@ -1123,6 +1123,7 @@ SHA256OBJS = # none by default ifdef NEED_SHA256 L_CFLAGS += -DCONFIG_SHA256 SHA256OBJS += src/crypto/sha256.c +SHA256OBJS += src/crypto/sha256-prf.c ifdef CONFIG_INTERNAL_SHA256 SHA256OBJS += src/crypto/sha256-internal.c endif diff --git a/wpa_supplicant/Makefile b/wpa_supplicant/Makefile index 70c5788a8..2f42ea100 100644 --- a/wpa_supplicant/Makefile +++ b/wpa_supplicant/Makefile @@ -1154,6 +1154,7 @@ SHA256OBJS = # none by default ifdef NEED_SHA256 CFLAGS += -DCONFIG_SHA256 SHA256OBJS += ../src/crypto/sha256.o +SHA256OBJS += ../src/crypto/sha256-prf.o ifdef CONFIG_INTERNAL_SHA256 SHA256OBJS += ../src/crypto/sha256-internal.o endif