Moved rsn_pmkid() into shared code to avoid duplication

[wpasupplicant] / src / common / wpa_common.c

diff --git a/src/common/wpa_common.c b/src/common/wpa_common.c
index c9ff319..0e3984f 100644 (file)
--- a/src/common/wpa_common.c
+++ b/src/common/wpa_common.c
@@ -568,3 +568,37 @@ void wpa_pmk_r1_to_ptk(const u8 *pmk_r1, const u8 *snonce, const u8 *anonce,
 }
 
 #endif /* CONFIG_IEEE80211R */
+
+
+/**
+ * rsn_pmkid - Calculate PMK identifier
+ * @pmk: Pairwise master key
+ * @pmk_len: Length of pmk in bytes
+ * @aa: Authenticator address
+ * @spa: Supplicant address
+ * @pmkid: Buffer for PMKID
+ * @use_sha256: Whether to use SHA256-based KDF
+ *
+ * IEEE Std 802.11i-2004 - 8.5.1.2 Pairwise key hierarchy
+ * PMKID = HMAC-SHA1-128(PMK, "PMK Name" || AA || SPA)
+ */
+void rsn_pmkid(const u8 *pmk, size_t pmk_len, const u8 *aa, const u8 *spa,
+              u8 *pmkid, int use_sha256)
+{
+       char *title = "PMK Name";
+       const u8 *addr[3];
+       const size_t len[3] = { 8, ETH_ALEN, ETH_ALEN };
+       unsigned char hash[SHA256_MAC_LEN];
+
+       addr[0] = (u8 *) title;
+       addr[1] = aa;
+       addr[2] = spa;
+
+#ifdef CONFIG_IEEE80211W
+       if (use_sha256)
+               hmac_sha256_vector(pmk, pmk_len, 3, addr, len, hash);
+       else
+#endif /* CONFIG_IEEE80211W */
+               hmac_sha1_vector(pmk, pmk_len, 3, addr, len, hash);
+       os_memcpy(pmkid, hash, PMKID_LEN);
+}