FILS: Advertise ERP domain in FILS Indication element

Calculate the hashed realm from hostapd erp_domain configuration
parameter and add this to the FILS Indication element when ERP is
enabled.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>

src/ap/ieee802_11_shared.c

@@ -613,7 +613,11 @@ u8 * hostapd_eid_fils_indic(struct hostapd_data *hapd, u8 *eid, int hessid)
 	*pos++ = WLAN_EID_FILS_INDICATION;
 	len = pos++;
 	/* TODO: B0..B2: Number of Public Key Identifiers */
-	/* TODO: B3..B5: Number of Realm Identifiers */
+	if (hapd->conf->erp_domain) {
+		/* TODO: Support for setting multiple domain identifiers */
+		/* B3..B5: Number of Realm Identifiers */
+		fils_info |= BIT(3);
+	}
 	/* TODO: B6: FILS IP Address Configuration */
 	if (hapd->conf->fils_cache_id_set)
 		fils_info |= BIT(7);
@@ -634,6 +638,13 @@ u8 * hostapd_eid_fils_indic(struct hostapd_data *hapd, u8 *eid, int hessid)
 		os_memcpy(pos, hapd->conf->hessid, ETH_ALEN);
 		pos += ETH_ALEN;
 	}
+	if (hapd->conf->erp_domain) {
+		u16 hash;
+
+		hash = fils_domain_name_hash(hapd->conf->erp_domain);
+		WPA_PUT_LE16(pos, hash);
+		pos += 2;
+	}
 	*len = pos - len - 1;
 #endif /* CONFIG_FILS */
 

src/common/wpa_common.c

@@ -9,6 +9,7 @@
 #include "includes.h"
 
 #include "common.h"
+#include "utils/crc32.h"
 #include "crypto/md5.h"
 #include "crypto/sha1.h"
 #include "crypto/sha256.h"
@@ -1755,3 +1756,25 @@ int wpa_select_ap_group_cipher(int wpa, int wpa_pairwise, int rsn_pairwise)
 		return WPA_CIPHER_CCMP_256;
 	return WPA_CIPHER_CCMP;
 }
+
+
+#ifdef CONFIG_FILS
+u16 fils_domain_name_hash(const char *domain)
+{
+	char buf[255], *wpos = buf;
+	const char *pos = domain;
+	size_t len;
+	u32 crc;
+
+	for (len = 0; len < sizeof(buf) && *pos; len++) {
+		if (isalpha(*pos) && isupper(*pos))
+			*wpos++ = tolower(*pos);
+		else
+			*wpos++ = *pos;
+		pos++;
+	}
+
+	crc = crc32((const u8 *) buf, len);
+	return crc & 0xffff;
+}
+#endif /* CONFIG_FILS */

src/common/wpa_common.h

@@ -455,5 +455,6 @@ int wpa_parse_cipher(const char *value);
 int wpa_write_ciphers(char *start, char *end, int ciphers, const char *delim);
 int wpa_select_ap_group_cipher(int wpa, int wpa_pairwise, int rsn_pairwise);
 unsigned int wpa_mic_len(int akmp);
+u16 fils_domain_name_hash(const char *domain);
 
 #endif /* WPA_COMMON_H */