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authorJouni Malinen <jouni.malinen@atheros.com>2010-02-19 16:54:07 (GMT)
committerJouni Malinen <j@w1.fi>2010-02-19 16:54:07 (GMT)
commit94d9bfd59bbfbdbe3e77ba95f73be3c84455ab9a (patch)
treed0df47afff426058d3f8de5190c4892b40ea53f9 /src/eap_server/eap_server_psk.c
parent6fa2ec2d2b7afa5347af0c4fa9beb8a147e897cf (diff)
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Rename EAP server source files to avoid duplicate names
This makes it easier to build both EAP peer and server functionality into the same project with some toolchains.
Diffstat (limited to 'src/eap_server/eap_server_psk.c')
-rw-r--r--src/eap_server/eap_server_psk.c517
1 files changed, 517 insertions, 0 deletions
diff --git a/src/eap_server/eap_server_psk.c b/src/eap_server/eap_server_psk.c
new file mode 100644
index 0000000..4c30346
--- /dev/null
+++ b/src/eap_server/eap_server_psk.c
@@ -0,0 +1,517 @@
+/*
+ * hostapd / EAP-PSK (RFC 4764) server
+ * Copyright (c) 2005-2007, 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.
+ *
+ * Note: EAP-PSK is an EAP authentication method and as such, completely
+ * different from WPA-PSK. This file is not needed for WPA-PSK functionality.
+ */
+
+#include "includes.h"
+
+#include "common.h"
+#include "crypto/aes_wrap.h"
+#include "eap_common/eap_psk_common.h"
+#include "eap_server/eap_i.h"
+
+
+struct eap_psk_data {
+ enum { PSK_1, PSK_3, SUCCESS, FAILURE } state;
+ u8 rand_s[EAP_PSK_RAND_LEN];
+ u8 rand_p[EAP_PSK_RAND_LEN];
+ u8 *id_p, *id_s;
+ size_t id_p_len, id_s_len;
+ u8 ak[EAP_PSK_AK_LEN], kdk[EAP_PSK_KDK_LEN], tek[EAP_PSK_TEK_LEN];
+ u8 msk[EAP_MSK_LEN];
+ u8 emsk[EAP_EMSK_LEN];
+};
+
+
+static void * eap_psk_init(struct eap_sm *sm)
+{
+ struct eap_psk_data *data;
+
+ data = os_zalloc(sizeof(*data));
+ if (data == NULL)
+ return NULL;
+ data->state = PSK_1;
+ data->id_s = (u8 *) "hostapd";
+ data->id_s_len = 7;
+
+ return data;
+}
+
+
+static void eap_psk_reset(struct eap_sm *sm, void *priv)
+{
+ struct eap_psk_data *data = priv;
+ os_free(data->id_p);
+ os_free(data);
+}
+
+
+static struct wpabuf * eap_psk_build_1(struct eap_sm *sm,
+ struct eap_psk_data *data, u8 id)
+{
+ struct wpabuf *req;
+ struct eap_psk_hdr_1 *psk;
+
+ wpa_printf(MSG_DEBUG, "EAP-PSK: PSK-1 (sending)");
+
+ if (os_get_random(data->rand_s, EAP_PSK_RAND_LEN)) {
+ wpa_printf(MSG_ERROR, "EAP-PSK: Failed to get random data");
+ data->state = FAILURE;
+ return NULL;
+ }
+ wpa_hexdump(MSG_MSGDUMP, "EAP-PSK: RAND_S (server rand)",
+ data->rand_s, EAP_PSK_RAND_LEN);
+
+ req = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_PSK,
+ sizeof(*psk) + data->id_s_len,
+ EAP_CODE_REQUEST, id);
+ if (req == NULL) {
+ wpa_printf(MSG_ERROR, "EAP-PSK: Failed to allocate memory "
+ "request");
+ data->state = FAILURE;
+ return NULL;
+ }
+
+ psk = wpabuf_put(req, sizeof(*psk));
+ psk->flags = EAP_PSK_FLAGS_SET_T(0); /* T=0 */
+ os_memcpy(psk->rand_s, data->rand_s, EAP_PSK_RAND_LEN);
+ wpabuf_put_data(req, data->id_s, data->id_s_len);
+
+ return req;
+}
+
+
+static struct wpabuf * eap_psk_build_3(struct eap_sm *sm,
+ struct eap_psk_data *data, u8 id)
+{
+ struct wpabuf *req;
+ struct eap_psk_hdr_3 *psk;
+ u8 *buf, *pchannel, nonce[16];
+ size_t buflen;
+
+ wpa_printf(MSG_DEBUG, "EAP-PSK: PSK-3 (sending)");
+
+ req = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_PSK,
+ sizeof(*psk) + 4 + 16 + 1, EAP_CODE_REQUEST, id);
+ if (req == NULL) {
+ wpa_printf(MSG_ERROR, "EAP-PSK: Failed to allocate memory "
+ "request");
+ data->state = FAILURE;
+ return NULL;
+ }
+
+ psk = wpabuf_put(req, sizeof(*psk));
+ psk->flags = EAP_PSK_FLAGS_SET_T(2); /* T=2 */
+ os_memcpy(psk->rand_s, data->rand_s, EAP_PSK_RAND_LEN);
+
+ /* MAC_S = OMAC1-AES-128(AK, ID_S||RAND_P) */
+ buflen = data->id_s_len + EAP_PSK_RAND_LEN;
+ buf = os_malloc(buflen);
+ if (buf == NULL)
+ goto fail;
+
+ os_memcpy(buf, data->id_s, data->id_s_len);
+ os_memcpy(buf + data->id_s_len, data->rand_p, EAP_PSK_RAND_LEN);
+ if (omac1_aes_128(data->ak, buf, buflen, psk->mac_s))
+ goto fail;
+ os_free(buf);
+
+ if (eap_psk_derive_keys(data->kdk, data->rand_p, data->tek, data->msk,
+ data->emsk))
+ goto fail;
+ wpa_hexdump_key(MSG_DEBUG, "EAP-PSK: TEK", data->tek, EAP_PSK_TEK_LEN);
+ wpa_hexdump_key(MSG_DEBUG, "EAP-PSK: MSK", data->msk, EAP_MSK_LEN);
+ wpa_hexdump_key(MSG_DEBUG, "EAP-PSK: EMSK", data->emsk, EAP_EMSK_LEN);
+
+ os_memset(nonce, 0, sizeof(nonce));
+ pchannel = wpabuf_put(req, 4 + 16 + 1);
+ os_memcpy(pchannel, nonce + 12, 4);
+ os_memset(pchannel + 4, 0, 16); /* Tag */
+ pchannel[4 + 16] = EAP_PSK_R_FLAG_DONE_SUCCESS << 6;
+ wpa_hexdump(MSG_DEBUG, "EAP-PSK: PCHANNEL (plaintext)",
+ pchannel, 4 + 16 + 1);
+ if (aes_128_eax_encrypt(data->tek, nonce, sizeof(nonce),
+ wpabuf_head(req), 22,
+ pchannel + 4 + 16, 1, pchannel + 4))
+ goto fail;
+ wpa_hexdump(MSG_DEBUG, "EAP-PSK: PCHANNEL (encrypted)",
+ pchannel, 4 + 16 + 1);
+
+ return req;
+
+fail:
+ wpabuf_free(req);
+ data->state = FAILURE;
+ return NULL;
+}
+
+
+static struct wpabuf * eap_psk_buildReq(struct eap_sm *sm, void *priv, u8 id)
+{
+ struct eap_psk_data *data = priv;
+
+ switch (data->state) {
+ case PSK_1:
+ return eap_psk_build_1(sm, data, id);
+ case PSK_3:
+ return eap_psk_build_3(sm, data, id);
+ default:
+ wpa_printf(MSG_DEBUG, "EAP-PSK: Unknown state %d in buildReq",
+ data->state);
+ break;
+ }
+ return NULL;
+}
+
+
+static Boolean eap_psk_check(struct eap_sm *sm, void *priv,
+ struct wpabuf *respData)
+{
+ struct eap_psk_data *data = priv;
+ size_t len;
+ u8 t;
+ const u8 *pos;
+
+ pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_PSK, respData, &len);
+ if (pos == NULL || len < 1) {
+ wpa_printf(MSG_INFO, "EAP-PSK: Invalid frame");
+ return TRUE;
+ }
+ t = EAP_PSK_FLAGS_GET_T(*pos);
+
+ wpa_printf(MSG_DEBUG, "EAP-PSK: received frame: T=%d", t);
+
+ if (data->state == PSK_1 && t != 1) {
+ wpa_printf(MSG_DEBUG, "EAP-PSK: Expected PSK-2 - "
+ "ignore T=%d", t);
+ return TRUE;
+ }
+
+ if (data->state == PSK_3 && t != 3) {
+ wpa_printf(MSG_DEBUG, "EAP-PSK: Expected PSK-4 - "
+ "ignore T=%d", t);
+ return TRUE;
+ }
+
+ if ((t == 1 && len < sizeof(struct eap_psk_hdr_2)) ||
+ (t == 3 && len < sizeof(struct eap_psk_hdr_4))) {
+ wpa_printf(MSG_DEBUG, "EAP-PSK: Too short frame");
+ return TRUE;
+ }
+
+ return FALSE;
+}
+
+
+static void eap_psk_process_2(struct eap_sm *sm,
+ struct eap_psk_data *data,
+ struct wpabuf *respData)
+{
+ const struct eap_psk_hdr_2 *resp;
+ u8 *pos, mac[EAP_PSK_MAC_LEN], *buf;
+ size_t left, buflen;
+ int i;
+ const u8 *cpos;
+
+ if (data->state != PSK_1)
+ return;
+
+ wpa_printf(MSG_DEBUG, "EAP-PSK: Received PSK-2");
+
+ cpos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_PSK, respData,
+ &left);
+ if (cpos == NULL || left < sizeof(*resp)) {
+ wpa_printf(MSG_INFO, "EAP-PSK: Invalid frame");
+ return;
+ }
+ resp = (const struct eap_psk_hdr_2 *) cpos;
+ cpos = (const u8 *) (resp + 1);
+ left -= sizeof(*resp);
+
+ os_free(data->id_p);
+ data->id_p = os_malloc(left);
+ if (data->id_p == NULL) {
+ wpa_printf(MSG_INFO, "EAP-PSK: Failed to allocate memory for "
+ "ID_P");
+ return;
+ }
+ os_memcpy(data->id_p, cpos, left);
+ data->id_p_len = left;
+ wpa_hexdump_ascii(MSG_MSGDUMP, "EAP-PSK: ID_P",
+ data->id_p, data->id_p_len);
+
+ if (eap_user_get(sm, data->id_p, data->id_p_len, 0) < 0) {
+ wpa_hexdump_ascii(MSG_DEBUG, "EAP-PSK: unknown ID_P",
+ data->id_p, data->id_p_len);
+ data->state = FAILURE;
+ return;
+ }
+
+ for (i = 0;
+ i < EAP_MAX_METHODS &&
+ (sm->user->methods[i].vendor != EAP_VENDOR_IETF ||
+ sm->user->methods[i].method != EAP_TYPE_NONE);
+ i++) {
+ if (sm->user->methods[i].vendor == EAP_VENDOR_IETF &&
+ sm->user->methods[i].method == EAP_TYPE_PSK)
+ break;
+ }
+
+ if (i >= EAP_MAX_METHODS ||
+ sm->user->methods[i].vendor != EAP_VENDOR_IETF ||
+ sm->user->methods[i].method != EAP_TYPE_PSK) {
+ wpa_hexdump_ascii(MSG_DEBUG,
+ "EAP-PSK: EAP-PSK not enabled for ID_P",
+ data->id_p, data->id_p_len);
+ data->state = FAILURE;
+ return;
+ }
+
+ if (sm->user->password == NULL ||
+ sm->user->password_len != EAP_PSK_PSK_LEN) {
+ wpa_hexdump_ascii(MSG_DEBUG, "EAP-PSK: invalid password in "
+ "user database for ID_P",
+ data->id_p, data->id_p_len);
+ data->state = FAILURE;
+ return;
+ }
+ if (eap_psk_key_setup(sm->user->password, data->ak, data->kdk)) {
+ data->state = FAILURE;
+ return;
+ }
+ wpa_hexdump_key(MSG_DEBUG, "EAP-PSK: AK", data->ak, EAP_PSK_AK_LEN);
+ wpa_hexdump_key(MSG_DEBUG, "EAP-PSK: KDK", data->kdk, EAP_PSK_KDK_LEN);
+
+ wpa_hexdump(MSG_MSGDUMP, "EAP-PSK: RAND_P (client rand)",
+ resp->rand_p, EAP_PSK_RAND_LEN);
+ os_memcpy(data->rand_p, resp->rand_p, EAP_PSK_RAND_LEN);
+
+ /* MAC_P = OMAC1-AES-128(AK, ID_P||ID_S||RAND_S||RAND_P) */
+ buflen = data->id_p_len + data->id_s_len + 2 * EAP_PSK_RAND_LEN;
+ buf = os_malloc(buflen);
+ if (buf == NULL) {
+ data->state = FAILURE;
+ return;
+ }
+ os_memcpy(buf, data->id_p, data->id_p_len);
+ pos = buf + data->id_p_len;
+ os_memcpy(pos, data->id_s, data->id_s_len);
+ pos += data->id_s_len;
+ os_memcpy(pos, data->rand_s, EAP_PSK_RAND_LEN);
+ pos += EAP_PSK_RAND_LEN;
+ os_memcpy(pos, data->rand_p, EAP_PSK_RAND_LEN);
+ if (omac1_aes_128(data->ak, buf, buflen, mac)) {
+ os_free(buf);
+ data->state = FAILURE;
+ return;
+ }
+ os_free(buf);
+ wpa_hexdump(MSG_DEBUG, "EAP-PSK: MAC_P", resp->mac_p, EAP_PSK_MAC_LEN);
+ if (os_memcmp(mac, resp->mac_p, EAP_PSK_MAC_LEN) != 0) {
+ wpa_printf(MSG_INFO, "EAP-PSK: Invalid MAC_P");
+ wpa_hexdump(MSG_MSGDUMP, "EAP-PSK: Expected MAC_P",
+ mac, EAP_PSK_MAC_LEN);
+ data->state = FAILURE;
+ return;
+ }
+
+ data->state = PSK_3;
+}
+
+
+static void eap_psk_process_4(struct eap_sm *sm,
+ struct eap_psk_data *data,
+ struct wpabuf *respData)
+{
+ const struct eap_psk_hdr_4 *resp;
+ u8 *decrypted, nonce[16];
+ size_t left;
+ const u8 *pos, *tag;
+
+ if (data->state != PSK_3)
+ return;
+
+ wpa_printf(MSG_DEBUG, "EAP-PSK: Received PSK-4");
+
+ pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_PSK, respData, &left);
+ if (pos == NULL || left < sizeof(*resp)) {
+ wpa_printf(MSG_INFO, "EAP-PSK: Invalid frame");
+ return;
+ }
+ resp = (const struct eap_psk_hdr_4 *) pos;
+ pos = (const u8 *) (resp + 1);
+ left -= sizeof(*resp);
+
+ wpa_hexdump(MSG_MSGDUMP, "EAP-PSK: Encrypted PCHANNEL", pos, left);
+
+ if (left < 4 + 16 + 1) {
+ wpa_printf(MSG_INFO, "EAP-PSK: Too short PCHANNEL data in "
+ "PSK-4 (len=%lu, expected 21)",
+ (unsigned long) left);
+ return;
+ }
+
+ if (pos[0] == 0 && pos[1] == 0 && pos[2] == 0 && pos[3] == 0) {
+ wpa_printf(MSG_DEBUG, "EAP-PSK: Nonce did not increase");
+ return;
+ }
+
+ os_memset(nonce, 0, 12);
+ os_memcpy(nonce + 12, pos, 4);
+ pos += 4;
+ left -= 4;
+ tag = pos;
+ pos += 16;
+ left -= 16;
+
+ decrypted = os_malloc(left);
+ if (decrypted == NULL)
+ return;
+ os_memcpy(decrypted, pos, left);
+
+ if (aes_128_eax_decrypt(data->tek, nonce, sizeof(nonce),
+ wpabuf_head(respData), 22, decrypted, left,
+ tag)) {
+ wpa_printf(MSG_WARNING, "EAP-PSK: PCHANNEL decryption failed");
+ os_free(decrypted);
+ data->state = FAILURE;
+ return;
+ }
+ wpa_hexdump(MSG_DEBUG, "EAP-PSK: Decrypted PCHANNEL message",
+ decrypted, left);
+
+ /* Verify R flag */
+ switch (decrypted[0] >> 6) {
+ case EAP_PSK_R_FLAG_CONT:
+ wpa_printf(MSG_DEBUG, "EAP-PSK: R flag - CONT - unsupported");
+ data->state = FAILURE;
+ break;
+ case EAP_PSK_R_FLAG_DONE_SUCCESS:
+ wpa_printf(MSG_DEBUG, "EAP-PSK: R flag - DONE_SUCCESS");
+ data->state = SUCCESS;
+ break;
+ case EAP_PSK_R_FLAG_DONE_FAILURE:
+ wpa_printf(MSG_DEBUG, "EAP-PSK: R flag - DONE_FAILURE");
+ data->state = FAILURE;
+ break;
+ }
+ os_free(decrypted);
+}
+
+
+static void eap_psk_process(struct eap_sm *sm, void *priv,
+ struct wpabuf *respData)
+{
+ struct eap_psk_data *data = priv;
+ const u8 *pos;
+ size_t len;
+
+ if (sm->user == NULL || sm->user->password == NULL) {
+ wpa_printf(MSG_INFO, "EAP-PSK: Plaintext password not "
+ "configured");
+ data->state = FAILURE;
+ return;
+ }
+
+ pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_PSK, respData, &len);
+ if (pos == NULL || len < 1)
+ return;
+
+ switch (EAP_PSK_FLAGS_GET_T(*pos)) {
+ case 1:
+ eap_psk_process_2(sm, data, respData);
+ break;
+ case 3:
+ eap_psk_process_4(sm, data, respData);
+ break;
+ }
+}
+
+
+static Boolean eap_psk_isDone(struct eap_sm *sm, void *priv)
+{
+ struct eap_psk_data *data = priv;
+ return data->state == SUCCESS || data->state == FAILURE;
+}
+
+
+static u8 * eap_psk_getKey(struct eap_sm *sm, void *priv, size_t *len)
+{
+ struct eap_psk_data *data = priv;
+ u8 *key;
+
+ if (data->state != SUCCESS)
+ return NULL;
+
+ key = os_malloc(EAP_MSK_LEN);
+ if (key == NULL)
+ return NULL;
+ os_memcpy(key, data->msk, EAP_MSK_LEN);
+ *len = EAP_MSK_LEN;
+
+ return key;
+}
+
+
+static u8 * eap_psk_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
+{
+ struct eap_psk_data *data = priv;
+ u8 *key;
+
+ if (data->state != SUCCESS)
+ return NULL;
+
+ key = os_malloc(EAP_EMSK_LEN);
+ if (key == NULL)
+ return NULL;
+ os_memcpy(key, data->emsk, EAP_EMSK_LEN);
+ *len = EAP_EMSK_LEN;
+
+ return key;
+}
+
+
+static Boolean eap_psk_isSuccess(struct eap_sm *sm, void *priv)
+{
+ struct eap_psk_data *data = priv;
+ return data->state == SUCCESS;
+}
+
+
+int eap_server_psk_register(void)
+{
+ struct eap_method *eap;
+ int ret;
+
+ eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
+ EAP_VENDOR_IETF, EAP_TYPE_PSK, "PSK");
+ if (eap == NULL)
+ return -1;
+
+ eap->init = eap_psk_init;
+ eap->reset = eap_psk_reset;
+ eap->buildReq = eap_psk_buildReq;
+ eap->check = eap_psk_check;
+ eap->process = eap_psk_process;
+ eap->isDone = eap_psk_isDone;
+ eap->getKey = eap_psk_getKey;
+ eap->isSuccess = eap_psk_isSuccess;
+ eap->get_emsk = eap_psk_get_emsk;
+
+ ret = eap_server_method_register(eap);
+ if (ret)
+ eap_server_method_free(eap);
+ return ret;
+}