Added support for using SHA256-based stronger key derivation for WPA2

IEEE 802.11w/D6.0 defines new AKMPs to indicate SHA256-based algorithms for
key derivation (and AES-CMAC for EAPOL-Key MIC). Add support for using new
AKMPs and clean up AKMP processing with helper functions in defs.h.
This commit is contained in:
Jouni Malinen 2008-08-31 22:57:28 +03:00
parent 9b71728bba
commit 565861976d
28 changed files with 343 additions and 151 deletions

View file

@ -79,6 +79,7 @@ int wpa_eapol_key_mic(const u8 *key, int ver, const u8 *buf, size_t len,
* @nonce2: SNonce or ANonce
* @ptk: Buffer for pairwise transient key
* @ptk_len: Length of PTK
* @use_sha256: Whether to use SHA256-based KDF
*
* IEEE Std 802.11i-2004 - 8.5.1.2 Pairwise key hierarchy
* PTK = PRF-X(PMK, "Pairwise key expansion",
@ -92,7 +93,7 @@ int wpa_eapol_key_mic(const u8 *key, int ver, const u8 *buf, size_t len,
void wpa_pmk_to_ptk(const u8 *pmk, size_t pmk_len, const char *label,
const u8 *addr1, const u8 *addr2,
const u8 *nonce1, const u8 *nonce2,
u8 *ptk, size_t ptk_len)
u8 *ptk, size_t ptk_len, int use_sha256)
{
u8 data[2 * ETH_ALEN + 2 * WPA_NONCE_LEN];
@ -114,7 +115,14 @@ void wpa_pmk_to_ptk(const u8 *pmk, size_t pmk_len, const char *label,
WPA_NONCE_LEN);
}
sha1_prf(pmk, pmk_len, label, data, sizeof(data), ptk, ptk_len);
#ifdef CONFIG_IEEE80211W
if (use_sha256)
sha256_prf(pmk, pmk_len, label, data, sizeof(data),
ptk, ptk_len);
else
#endif /* CONFIG_IEEE80211W */
sha1_prf(pmk, pmk_len, label, data, sizeof(data), ptk,
ptk_len);
wpa_printf(MSG_DEBUG, "WPA: PTK derivation - A1=" MACSTR " A2=" MACSTR,
MAC2STR(addr1), MAC2STR(addr2));
@ -214,6 +222,12 @@ static int rsn_key_mgmt_to_bitfield(const u8 *s)
if (RSN_SELECTOR_GET(s) == RSN_AUTH_KEY_MGMT_FT_PSK)
return WPA_KEY_MGMT_FT_PSK;
#endif /* CONFIG_IEEE80211R */
#ifdef CONFIG_IEEE80211W
if (RSN_SELECTOR_GET(s) == RSN_AUTH_KEY_MGMT_802_1X_SHA256)
return WPA_KEY_MGMT_IEEE8021X_SHA256;
if (RSN_SELECTOR_GET(s) == RSN_AUTH_KEY_MGMT_PSK_SHA256)
return WPA_KEY_MGMT_PSK_SHA256;
#endif /* CONFIG_IEEE80211W */
return 0;
}
#endif /* CONFIG_NO_WPA2 */