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-rw-r--r--contrib/wpa/src/wps/wps_common.c337
1 files changed, 337 insertions, 0 deletions
diff --git a/contrib/wpa/src/wps/wps_common.c b/contrib/wpa/src/wps/wps_common.c
new file mode 100644
index 0000000..48af303
--- /dev/null
+++ b/contrib/wpa/src/wps/wps_common.c
@@ -0,0 +1,337 @@
+/*
+ * Wi-Fi Protected Setup - common functionality
+ * Copyright (c) 2008, Jouni Malinen <j@w1.fi>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Alternatively, this software may be distributed under the terms of BSD
+ * license.
+ *
+ * See README and COPYING for more details.
+ */
+
+#include "includes.h"
+
+#include "common.h"
+#include "dh_groups.h"
+#include "sha256.h"
+#include "aes_wrap.h"
+#include "crypto.h"
+#include "wps_i.h"
+#include "wps_dev_attr.h"
+
+
+void wps_kdf(const u8 *key, const u8 *label_prefix, size_t label_prefix_len,
+ const char *label, u8 *res, size_t res_len)
+{
+ u8 i_buf[4], key_bits[4];
+ const u8 *addr[4];
+ size_t len[4];
+ int i, iter;
+ u8 hash[SHA256_MAC_LEN], *opos;
+ size_t left;
+
+ WPA_PUT_BE32(key_bits, res_len * 8);
+
+ addr[0] = i_buf;
+ len[0] = sizeof(i_buf);
+ addr[1] = label_prefix;
+ len[1] = label_prefix_len;
+ addr[2] = (const u8 *) label;
+ len[2] = os_strlen(label);
+ addr[3] = key_bits;
+ len[3] = sizeof(key_bits);
+
+ iter = (res_len + SHA256_MAC_LEN - 1) / SHA256_MAC_LEN;
+ opos = res;
+ left = res_len;
+
+ for (i = 1; i <= iter; i++) {
+ WPA_PUT_BE32(i_buf, i);
+ hmac_sha256_vector(key, SHA256_MAC_LEN, 4, addr, len, hash);
+ if (i < iter) {
+ os_memcpy(opos, hash, SHA256_MAC_LEN);
+ opos += SHA256_MAC_LEN;
+ left -= SHA256_MAC_LEN;
+ } else
+ os_memcpy(opos, hash, left);
+ }
+}
+
+
+int wps_derive_keys(struct wps_data *wps)
+{
+ struct wpabuf *pubkey, *dh_shared;
+ u8 dhkey[SHA256_MAC_LEN], kdk[SHA256_MAC_LEN];
+ const u8 *addr[3];
+ size_t len[3];
+ u8 keys[WPS_AUTHKEY_LEN + WPS_KEYWRAPKEY_LEN + WPS_EMSK_LEN];
+
+ if (wps->dh_privkey == NULL) {
+ wpa_printf(MSG_DEBUG, "WPS: Own DH private key not available");
+ return -1;
+ }
+
+ pubkey = wps->registrar ? wps->dh_pubkey_e : wps->dh_pubkey_r;
+ if (pubkey == NULL) {
+ wpa_printf(MSG_DEBUG, "WPS: Peer DH public key not available");
+ return -1;
+ }
+
+ dh_shared = dh_derive_shared(pubkey, wps->dh_privkey,
+ dh_groups_get(WPS_DH_GROUP));
+ dh_shared = wpabuf_zeropad(dh_shared, 192);
+ if (dh_shared == NULL) {
+ wpa_printf(MSG_DEBUG, "WPS: Failed to derive DH shared key");
+ return -1;
+ }
+
+ /* Own DH private key is not needed anymore */
+ wpabuf_free(wps->dh_privkey);
+ wps->dh_privkey = NULL;
+
+ wpa_hexdump_buf_key(MSG_DEBUG, "WPS: DH shared key", dh_shared);
+
+ /* DHKey = SHA-256(g^AB mod p) */
+ addr[0] = wpabuf_head(dh_shared);
+ len[0] = wpabuf_len(dh_shared);
+ sha256_vector(1, addr, len, dhkey);
+ wpa_hexdump_key(MSG_DEBUG, "WPS: DHKey", dhkey, sizeof(dhkey));
+ wpabuf_free(dh_shared);
+
+ /* KDK = HMAC-SHA-256_DHKey(N1 || EnrolleeMAC || N2) */
+ addr[0] = wps->nonce_e;
+ len[0] = WPS_NONCE_LEN;
+ addr[1] = wps->mac_addr_e;
+ len[1] = ETH_ALEN;
+ addr[2] = wps->nonce_r;
+ len[2] = WPS_NONCE_LEN;
+ hmac_sha256_vector(dhkey, sizeof(dhkey), 3, addr, len, kdk);
+ wpa_hexdump_key(MSG_DEBUG, "WPS: KDK", kdk, sizeof(kdk));
+
+ wps_kdf(kdk, NULL, 0, "Wi-Fi Easy and Secure Key Derivation",
+ keys, sizeof(keys));
+ os_memcpy(wps->authkey, keys, WPS_AUTHKEY_LEN);
+ os_memcpy(wps->keywrapkey, keys + WPS_AUTHKEY_LEN, WPS_KEYWRAPKEY_LEN);
+ os_memcpy(wps->emsk, keys + WPS_AUTHKEY_LEN + WPS_KEYWRAPKEY_LEN,
+ WPS_EMSK_LEN);
+
+ wpa_hexdump_key(MSG_DEBUG, "WPS: AuthKey",
+ wps->authkey, WPS_AUTHKEY_LEN);
+ wpa_hexdump_key(MSG_DEBUG, "WPS: KeyWrapKey",
+ wps->keywrapkey, WPS_KEYWRAPKEY_LEN);
+ wpa_hexdump_key(MSG_DEBUG, "WPS: EMSK", wps->emsk, WPS_EMSK_LEN);
+
+ return 0;
+}
+
+
+int wps_derive_mgmt_keys(struct wps_data *wps)
+{
+ u8 nonces[2 * WPS_NONCE_LEN];
+ u8 keys[WPS_MGMTAUTHKEY_LEN + WPS_MGMTENCKEY_LEN];
+ u8 hash[SHA256_MAC_LEN];
+ const u8 *addr[2];
+ size_t len[2];
+ const char *auth_label = "WFA-WLAN-Management-MgmtAuthKey";
+ const char *enc_label = "WFA-WLAN-Management-MgmtEncKey";
+
+ /* MgmtAuthKey || MgmtEncKey =
+ * kdf(EMSK, N1 || N2 || "WFA-WLAN-Management-Keys", 384) */
+ os_memcpy(nonces, wps->nonce_e, WPS_NONCE_LEN);
+ os_memcpy(nonces + WPS_NONCE_LEN, wps->nonce_r, WPS_NONCE_LEN);
+ wps_kdf(wps->emsk, nonces, sizeof(nonces), "WFA-WLAN-Management-Keys",
+ keys, sizeof(keys));
+ os_memcpy(wps->mgmt_auth_key, keys, WPS_MGMTAUTHKEY_LEN);
+ os_memcpy(wps->mgmt_enc_key, keys + WPS_MGMTAUTHKEY_LEN,
+ WPS_MGMTENCKEY_LEN);
+
+ addr[0] = nonces;
+ len[0] = sizeof(nonces);
+
+ /* MgmtEncKeyID = first 128 bits of
+ * SHA-256(N1 || N2 || "WFA-WLAN-Management-MgmtAuthKey") */
+ addr[1] = (const u8 *) auth_label;
+ len[1] = os_strlen(auth_label);
+ sha256_vector(2, addr, len, hash);
+ os_memcpy(wps->mgmt_auth_key_id, hash, WPS_MGMT_KEY_ID_LEN);
+
+ /* MgmtEncKeyID = first 128 bits of
+ * SHA-256(N1 || N2 || "WFA-WLAN-Management-MgmtEncKey") */
+ addr[1] = (const u8 *) enc_label;
+ len[1] = os_strlen(enc_label);
+ sha256_vector(2, addr, len, hash);
+ os_memcpy(wps->mgmt_enc_key_id, hash, WPS_MGMT_KEY_ID_LEN);
+
+ wpa_hexdump_key(MSG_DEBUG, "WPS: MgmtAuthKey",
+ wps->mgmt_auth_key, WPS_MGMTAUTHKEY_LEN);
+ wpa_hexdump(MSG_DEBUG, "WPS: MgmtAuthKeyID",
+ wps->mgmt_auth_key_id, WPS_MGMT_KEY_ID_LEN);
+ wpa_hexdump_key(MSG_DEBUG, "WPS: MgmtEncKey",
+ wps->mgmt_enc_key, WPS_MGMTENCKEY_LEN);
+ wpa_hexdump(MSG_DEBUG, "WPS: MgmtEncKeyID",
+ wps->mgmt_enc_key_id, WPS_MGMT_KEY_ID_LEN);
+
+ return 0;
+}
+
+
+void wps_derive_psk(struct wps_data *wps, const u8 *dev_passwd,
+ size_t dev_passwd_len)
+{
+ u8 hash[SHA256_MAC_LEN];
+
+ hmac_sha256(wps->authkey, WPS_AUTHKEY_LEN, dev_passwd,
+ (dev_passwd_len + 1) / 2, hash);
+ os_memcpy(wps->psk1, hash, WPS_PSK_LEN);
+ hmac_sha256(wps->authkey, WPS_AUTHKEY_LEN,
+ dev_passwd + (dev_passwd_len + 1) / 2,
+ dev_passwd_len / 2, hash);
+ os_memcpy(wps->psk2, hash, WPS_PSK_LEN);
+
+ wpa_hexdump_ascii_key(MSG_DEBUG, "WPS: Device Password",
+ dev_passwd, dev_passwd_len);
+ wpa_hexdump_key(MSG_DEBUG, "WPS: PSK1", wps->psk1, WPS_PSK_LEN);
+ wpa_hexdump_key(MSG_DEBUG, "WPS: PSK2", wps->psk2, WPS_PSK_LEN);
+}
+
+
+struct wpabuf * wps_decrypt_encr_settings(struct wps_data *wps, const u8 *encr,
+ size_t encr_len)
+{
+ struct wpabuf *decrypted;
+ const size_t block_size = 16;
+ size_t i;
+ u8 pad;
+ const u8 *pos;
+
+ /* AES-128-CBC */
+ if (encr == NULL || encr_len < 2 * block_size || encr_len % block_size)
+ {
+ wpa_printf(MSG_DEBUG, "WPS: No Encrypted Settings received");
+ return NULL;
+ }
+
+ decrypted = wpabuf_alloc(encr_len - block_size);
+ if (decrypted == NULL)
+ return NULL;
+
+ wpa_hexdump(MSG_MSGDUMP, "WPS: Encrypted Settings", encr, encr_len);
+ wpabuf_put_data(decrypted, encr + block_size, encr_len - block_size);
+ if (aes_128_cbc_decrypt(wps->keywrapkey, encr, wpabuf_mhead(decrypted),
+ wpabuf_len(decrypted))) {
+ wpabuf_free(decrypted);
+ return NULL;
+ }
+
+ wpa_hexdump_buf_key(MSG_MSGDUMP, "WPS: Decrypted Encrypted Settings",
+ decrypted);
+
+ pos = wpabuf_head_u8(decrypted) + wpabuf_len(decrypted) - 1;
+ pad = *pos;
+ if (pad > wpabuf_len(decrypted)) {
+ wpa_printf(MSG_DEBUG, "WPS: Invalid PKCS#5 v2.0 pad value");
+ wpabuf_free(decrypted);
+ return NULL;
+ }
+ for (i = 0; i < pad; i++) {
+ if (*pos-- != pad) {
+ wpa_printf(MSG_DEBUG, "WPS: Invalid PKCS#5 v2.0 pad "
+ "string");
+ wpabuf_free(decrypted);
+ return NULL;
+ }
+ }
+ decrypted->used -= pad;
+
+ return decrypted;
+}
+
+
+/**
+ * wps_pin_checksum - Compute PIN checksum
+ * @pin: Seven digit PIN (i.e., eight digit PIN without the checksum digit)
+ * Returns: Checksum digit
+ */
+unsigned int wps_pin_checksum(unsigned int pin)
+{
+ unsigned int accum = 0;
+ while (pin) {
+ accum += 3 * (pin % 10);
+ pin /= 10;
+ accum += pin % 10;
+ pin /= 10;
+ }
+
+ return (10 - accum % 10) % 10;
+}
+
+
+/**
+ * wps_pin_valid - Check whether a PIN has a valid checksum
+ * @pin: Eight digit PIN (i.e., including the checksum digit)
+ * Returns: 1 if checksum digit is valid, or 0 if not
+ */
+unsigned int wps_pin_valid(unsigned int pin)
+{
+ return wps_pin_checksum(pin / 10) == (pin % 10);
+}
+
+
+/**
+ * wps_generate_pin - Generate a random PIN
+ * Returns: Eight digit PIN (i.e., including the checksum digit)
+ */
+unsigned int wps_generate_pin(void)
+{
+ unsigned int val;
+
+ /* Generate seven random digits for the PIN */
+ if (os_get_random((unsigned char *) &val, sizeof(val)) < 0) {
+ struct os_time now;
+ os_get_time(&now);
+ val = os_random() ^ now.sec ^ now.usec;
+ }
+ val %= 10000000;
+
+ /* Append checksum digit */
+ return val * 10 + wps_pin_checksum(val);
+}
+
+
+void wps_fail_event(struct wps_context *wps, enum wps_msg_type msg)
+{
+ union wps_event_data data;
+
+ if (wps->event_cb == NULL)
+ return;
+
+ os_memset(&data, 0, sizeof(data));
+ data.fail.msg = msg;
+ wps->event_cb(wps->cb_ctx, WPS_EV_FAIL, &data);
+}
+
+
+void wps_success_event(struct wps_context *wps)
+{
+ if (wps->event_cb == NULL)
+ return;
+
+ wps->event_cb(wps->cb_ctx, WPS_EV_SUCCESS, NULL);
+}
+
+
+void wps_pwd_auth_fail_event(struct wps_context *wps, int enrollee, int part)
+{
+ union wps_event_data data;
+
+ if (wps->event_cb == NULL)
+ return;
+
+ os_memset(&data, 0, sizeof(data));
+ data.pwd_auth_fail.enrollee = enrollee;
+ data.pwd_auth_fail.part = part;
+ wps->event_cb(wps->cb_ctx, WPS_EV_PWD_AUTH_FAIL, &data);
+}
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