remove @EAP_LDFLAGS@, no longer exists
[mech_eap.orig] / libeap / src / eap_server / eap_server_ikev2.c
diff --git a/libeap/src/eap_server/eap_server_ikev2.c b/libeap/src/eap_server/eap_server_ikev2.c
new file mode 100644 (file)
index 0000000..ec4fa87
--- /dev/null
@@ -0,0 +1,539 @@
+/*
+ * EAP-IKEv2 server (RFC 5106)
+ * Copyright (c) 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.
+ */
+
+#include "includes.h"
+
+#include "common.h"
+#include "eap_i.h"
+#include "eap_common/eap_ikev2_common.h"
+#include "ikev2.h"
+
+
+struct eap_ikev2_data {
+       struct ikev2_initiator_data ikev2;
+       enum { MSG, FRAG_ACK, WAIT_FRAG_ACK, DONE, FAIL } state;
+       struct wpabuf *in_buf;
+       struct wpabuf *out_buf;
+       size_t out_used;
+       size_t fragment_size;
+       int keys_ready;
+       u8 keymat[EAP_MSK_LEN + EAP_EMSK_LEN];
+       int keymat_ok;
+};
+
+
+static const u8 * eap_ikev2_get_shared_secret(void *ctx, const u8 *IDr,
+                                             size_t IDr_len,
+                                             size_t *secret_len)
+{
+       struct eap_sm *sm = ctx;
+
+       if (IDr == NULL) {
+               wpa_printf(MSG_DEBUG, "EAP-IKEV2: No IDr received - default "
+                          "to user identity from EAP-Identity");
+               IDr = sm->identity;
+               IDr_len = sm->identity_len;
+       }
+
+       if (eap_user_get(sm, IDr, IDr_len, 0) < 0 || sm->user == NULL ||
+           sm->user->password == NULL) {
+               wpa_printf(MSG_DEBUG, "EAP-IKEV2: No user entry found");
+               return NULL;
+       }
+
+       *secret_len = sm->user->password_len;
+       return sm->user->password;
+}
+
+
+static const char * eap_ikev2_state_txt(int state)
+{
+       switch (state) {
+       case MSG:
+               return "MSG";
+       case FRAG_ACK:
+               return "FRAG_ACK";
+       case WAIT_FRAG_ACK:
+               return "WAIT_FRAG_ACK";
+       case DONE:
+               return "DONE";
+       case FAIL:
+               return "FAIL";
+       default:
+               return "?";
+       }
+}
+
+
+static void eap_ikev2_state(struct eap_ikev2_data *data, int state)
+{
+       wpa_printf(MSG_DEBUG, "EAP-IKEV2: %s -> %s",
+                  eap_ikev2_state_txt(data->state),
+                  eap_ikev2_state_txt(state));
+       data->state = state;
+}
+
+
+static void * eap_ikev2_init(struct eap_sm *sm)
+{
+       struct eap_ikev2_data *data;
+
+       data = os_zalloc(sizeof(*data));
+       if (data == NULL)
+               return NULL;
+       data->state = MSG;
+       data->fragment_size = sm->fragment_size > 0 ? sm->fragment_size :
+               IKEV2_FRAGMENT_SIZE;
+       data->ikev2.state = SA_INIT;
+       data->ikev2.peer_auth = PEER_AUTH_SECRET;
+       data->ikev2.key_pad = (u8 *) os_strdup("Key Pad for EAP-IKEv2");
+       if (data->ikev2.key_pad == NULL)
+               goto failed;
+       data->ikev2.key_pad_len = 21;
+
+       /* TODO: make proposals configurable */
+       data->ikev2.proposal.proposal_num = 1;
+       data->ikev2.proposal.integ = AUTH_HMAC_SHA1_96;
+       data->ikev2.proposal.prf = PRF_HMAC_SHA1;
+       data->ikev2.proposal.encr = ENCR_AES_CBC;
+       data->ikev2.proposal.dh = DH_GROUP2_1024BIT_MODP;
+
+       data->ikev2.IDi = (u8 *) os_strdup("hostapd");
+       data->ikev2.IDi_len = 7;
+
+       data->ikev2.get_shared_secret = eap_ikev2_get_shared_secret;
+       data->ikev2.cb_ctx = sm;
+
+       return data;
+
+failed:
+       ikev2_initiator_deinit(&data->ikev2);
+       os_free(data);
+       return NULL;
+}
+
+
+static void eap_ikev2_reset(struct eap_sm *sm, void *priv)
+{
+       struct eap_ikev2_data *data = priv;
+       wpabuf_free(data->in_buf);
+       wpabuf_free(data->out_buf);
+       ikev2_initiator_deinit(&data->ikev2);
+       os_free(data);
+}
+
+
+static struct wpabuf * eap_ikev2_build_msg(struct eap_ikev2_data *data, u8 id)
+{
+       struct wpabuf *req;
+       u8 flags;
+       size_t send_len, plen, icv_len = 0;
+
+       wpa_printf(MSG_DEBUG, "EAP-IKEV2: Generating Request");
+
+       flags = 0;
+       send_len = wpabuf_len(data->out_buf) - data->out_used;
+       if (1 + send_len > data->fragment_size) {
+               send_len = data->fragment_size - 1;
+               flags |= IKEV2_FLAGS_MORE_FRAGMENTS;
+               if (data->out_used == 0) {
+                       flags |= IKEV2_FLAGS_LENGTH_INCLUDED;
+                       send_len -= 4;
+               }
+       }
+
+       plen = 1 + send_len;
+       if (flags & IKEV2_FLAGS_LENGTH_INCLUDED)
+               plen += 4;
+       if (data->keys_ready) {
+               const struct ikev2_integ_alg *integ;
+               wpa_printf(MSG_DEBUG, "EAP-IKEV2: Add Integrity Checksum "
+                          "Data");
+               flags |= IKEV2_FLAGS_ICV_INCLUDED;
+               integ = ikev2_get_integ(data->ikev2.proposal.integ);
+               if (integ == NULL) {
+                       wpa_printf(MSG_DEBUG, "EAP-IKEV2: Unknown INTEG "
+                                  "transform / cannot generate ICV");
+                       return NULL;
+               }
+               icv_len = integ->hash_len;
+
+               plen += icv_len;
+       }
+       req = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_IKEV2, plen,
+                           EAP_CODE_REQUEST, id);
+       if (req == NULL)
+               return NULL;
+
+       wpabuf_put_u8(req, flags); /* Flags */
+       if (flags & IKEV2_FLAGS_LENGTH_INCLUDED)
+               wpabuf_put_be32(req, wpabuf_len(data->out_buf));
+
+       wpabuf_put_data(req, wpabuf_head_u8(data->out_buf) + data->out_used,
+                       send_len);
+       data->out_used += send_len;
+
+       if (flags & IKEV2_FLAGS_ICV_INCLUDED) {
+               const u8 *msg = wpabuf_head(req);
+               size_t len = wpabuf_len(req);
+               ikev2_integ_hash(data->ikev2.proposal.integ,
+                                data->ikev2.keys.SK_ai,
+                                data->ikev2.keys.SK_integ_len,
+                                msg, len, wpabuf_put(req, icv_len));
+       }
+
+       if (data->out_used == wpabuf_len(data->out_buf)) {
+               wpa_printf(MSG_DEBUG, "EAP-IKEV2: Sending out %lu bytes "
+                          "(message sent completely)",
+                          (unsigned long) send_len);
+               wpabuf_free(data->out_buf);
+               data->out_buf = NULL;
+               data->out_used = 0;
+       } else {
+               wpa_printf(MSG_DEBUG, "EAP-IKEV2: Sending out %lu bytes "
+                          "(%lu more to send)", (unsigned long) send_len,
+                          (unsigned long) wpabuf_len(data->out_buf) -
+                          data->out_used);
+               eap_ikev2_state(data, WAIT_FRAG_ACK);
+       }
+
+       return req;
+}
+
+
+static struct wpabuf * eap_ikev2_buildReq(struct eap_sm *sm, void *priv, u8 id)
+{
+       struct eap_ikev2_data *data = priv;
+
+       switch (data->state) {
+       case MSG:
+               if (data->out_buf == NULL) {
+                       data->out_buf = ikev2_initiator_build(&data->ikev2);
+                       if (data->out_buf == NULL) {
+                               wpa_printf(MSG_DEBUG, "EAP-IKEV2: Failed to "
+                                          "generate IKEv2 message");
+                               return NULL;
+                       }
+                       data->out_used = 0;
+               }
+               /* pass through */
+       case WAIT_FRAG_ACK:
+               return eap_ikev2_build_msg(data, id);
+       case FRAG_ACK:
+               return eap_ikev2_build_frag_ack(id, EAP_CODE_REQUEST);
+       default:
+               wpa_printf(MSG_DEBUG, "EAP-IKEV2: Unexpected state %d in "
+                          "buildReq", data->state);
+               return NULL;
+       }
+}
+
+
+static Boolean eap_ikev2_check(struct eap_sm *sm, void *priv,
+                              struct wpabuf *respData)
+{
+       const u8 *pos;
+       size_t len;
+
+       pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_IKEV2, respData,
+                              &len);
+       if (pos == NULL) {
+               wpa_printf(MSG_INFO, "EAP-IKEV2: Invalid frame");
+               return TRUE;
+       }
+
+       return FALSE;
+}
+
+
+static int eap_ikev2_process_icv(struct eap_ikev2_data *data,
+                                const struct wpabuf *respData,
+                                u8 flags, const u8 *pos, const u8 **end)
+{
+       if (flags & IKEV2_FLAGS_ICV_INCLUDED) {
+               int icv_len = eap_ikev2_validate_icv(
+                       data->ikev2.proposal.integ, &data->ikev2.keys, 0,
+                       respData, pos, *end);
+               if (icv_len < 0)
+                       return -1;
+               /* Hide Integrity Checksum Data from further processing */
+               *end -= icv_len;
+       } else if (data->keys_ready) {
+               wpa_printf(MSG_INFO, "EAP-IKEV2: The message should have "
+                          "included integrity checksum");
+               return -1;
+       }
+
+       return 0;
+}
+
+
+static int eap_ikev2_process_cont(struct eap_ikev2_data *data,
+                                 const u8 *buf, size_t len)
+{
+       /* Process continuation of a pending message */
+       if (len > wpabuf_tailroom(data->in_buf)) {
+               wpa_printf(MSG_DEBUG, "EAP-IKEV2: Fragment overflow");
+               eap_ikev2_state(data, FAIL);
+               return -1;
+       }
+
+       wpabuf_put_data(data->in_buf, buf, len);
+       wpa_printf(MSG_DEBUG, "EAP-IKEV2: Received %lu bytes, waiting for %lu "
+                  "bytes more", (unsigned long) len,
+                  (unsigned long) wpabuf_tailroom(data->in_buf));
+
+       return 0;
+}
+
+
+static int eap_ikev2_process_fragment(struct eap_ikev2_data *data,
+                                     u8 flags, u32 message_length,
+                                     const u8 *buf, size_t len)
+{
+       /* Process a fragment that is not the last one of the message */
+       if (data->in_buf == NULL && !(flags & IKEV2_FLAGS_LENGTH_INCLUDED)) {
+               wpa_printf(MSG_DEBUG, "EAP-IKEV2: No Message Length field in "
+                          "a fragmented packet");
+               return -1;
+       }
+
+       if (data->in_buf == NULL) {
+               /* First fragment of the message */
+               data->in_buf = wpabuf_alloc(message_length);
+               if (data->in_buf == NULL) {
+                       wpa_printf(MSG_DEBUG, "EAP-IKEV2: No memory for "
+                                  "message");
+                       return -1;
+               }
+               wpabuf_put_data(data->in_buf, buf, len);
+               wpa_printf(MSG_DEBUG, "EAP-IKEV2: Received %lu bytes in first "
+                          "fragment, waiting for %lu bytes more",
+                          (unsigned long) len,
+                          (unsigned long) wpabuf_tailroom(data->in_buf));
+       }
+
+       return 0;
+}
+
+
+static int eap_ikev2_server_keymat(struct eap_ikev2_data *data)
+{
+       if (eap_ikev2_derive_keymat(
+                   data->ikev2.proposal.prf, &data->ikev2.keys,
+                   data->ikev2.i_nonce, data->ikev2.i_nonce_len,
+                   data->ikev2.r_nonce, data->ikev2.r_nonce_len,
+                   data->keymat) < 0) {
+               wpa_printf(MSG_DEBUG, "EAP-IKEV2: Failed to derive "
+                          "key material");
+               return -1;
+       }
+       data->keymat_ok = 1;
+       return 0;
+}
+
+
+static void eap_ikev2_process(struct eap_sm *sm, void *priv,
+                             struct wpabuf *respData)
+{
+       struct eap_ikev2_data *data = priv;
+       const u8 *start, *pos, *end;
+       size_t len;
+       u8 flags;
+       u32 message_length = 0;
+       struct wpabuf tmpbuf;
+
+       pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_IKEV2, respData,
+                              &len);
+       if (pos == NULL)
+               return; /* Should not happen; message already verified */
+
+       start = pos;
+       end = start + len;
+
+       if (len == 0) {
+               /* fragment ack */
+               flags = 0;
+       } else
+               flags = *pos++;
+
+       if (eap_ikev2_process_icv(data, respData, flags, pos, &end) < 0) {
+               eap_ikev2_state(data, FAIL);
+               return;
+       }
+
+       if (flags & IKEV2_FLAGS_LENGTH_INCLUDED) {
+               if (end - pos < 4) {
+                       wpa_printf(MSG_DEBUG, "EAP-IKEV2: Message underflow");
+                       eap_ikev2_state(data, FAIL);
+                       return;
+               }
+               message_length = WPA_GET_BE32(pos);
+               pos += 4;
+
+               if (message_length < (u32) (end - pos)) {
+                       wpa_printf(MSG_DEBUG, "EAP-IKEV2: Invalid Message "
+                                  "Length (%d; %ld remaining in this msg)",
+                                  message_length, (long) (end - pos));
+                       eap_ikev2_state(data, FAIL);
+                       return;
+               }
+       }
+       wpa_printf(MSG_DEBUG, "EAP-IKEV2: Received packet: Flags 0x%x "
+                  "Message Length %u", flags, message_length);
+
+       if (data->state == WAIT_FRAG_ACK) {
+               if (len != 0) {
+                       wpa_printf(MSG_DEBUG, "EAP-IKEV2: Unexpected payload "
+                                  "in WAIT_FRAG_ACK state");
+                       eap_ikev2_state(data, FAIL);
+                       return;
+               }
+               wpa_printf(MSG_DEBUG, "EAP-IKEV2: Fragment acknowledged");
+               eap_ikev2_state(data, MSG);
+               return;
+       }
+
+       if (data->in_buf && eap_ikev2_process_cont(data, pos, end - pos) < 0) {
+               eap_ikev2_state(data, FAIL);
+               return;
+       }
+               
+       if (flags & IKEV2_FLAGS_MORE_FRAGMENTS) {
+               if (eap_ikev2_process_fragment(data, flags, message_length,
+                                              pos, end - pos) < 0)
+                       eap_ikev2_state(data, FAIL);
+               else
+                       eap_ikev2_state(data, FRAG_ACK);
+               return;
+       } else if (data->state == FRAG_ACK) {
+               wpa_printf(MSG_DEBUG, "EAP-TNC: All fragments received");
+               data->state = MSG;
+       }
+
+       if (data->in_buf == NULL) {
+               /* Wrap unfragmented messages as wpabuf without extra copy */
+               wpabuf_set(&tmpbuf, pos, end - pos);
+               data->in_buf = &tmpbuf;
+       }
+
+       if (ikev2_initiator_process(&data->ikev2, data->in_buf) < 0) {
+               if (data->in_buf == &tmpbuf)
+                       data->in_buf = NULL;
+               eap_ikev2_state(data, FAIL);
+               return;
+       }
+
+       switch (data->ikev2.state) {
+       case SA_AUTH:
+               /* SA_INIT was sent out, so message have to be
+                * integrity protected from now on. */
+               data->keys_ready = 1;
+               break;
+       case IKEV2_DONE:
+               if (data->state == FAIL)
+                       break;
+               wpa_printf(MSG_DEBUG, "EAP-IKEV2: Authentication completed "
+                          "successfully");
+               if (eap_ikev2_server_keymat(data))
+                       break;
+               eap_ikev2_state(data, DONE);
+               break;
+       default:
+               break;
+       }
+
+       if (data->in_buf != &tmpbuf)
+               wpabuf_free(data->in_buf);
+       data->in_buf = NULL;
+}
+
+
+static Boolean eap_ikev2_isDone(struct eap_sm *sm, void *priv)
+{
+       struct eap_ikev2_data *data = priv;
+       return data->state == DONE || data->state == FAIL;
+}
+
+
+static Boolean eap_ikev2_isSuccess(struct eap_sm *sm, void *priv)
+{
+       struct eap_ikev2_data *data = priv;
+       return data->state == DONE && data->ikev2.state == IKEV2_DONE &&
+               data->keymat_ok;
+}
+
+
+static u8 * eap_ikev2_getKey(struct eap_sm *sm, void *priv, size_t *len)
+{
+       struct eap_ikev2_data *data = priv;
+       u8 *key;
+
+       if (data->state != DONE || !data->keymat_ok)
+               return NULL;
+
+       key = os_malloc(EAP_MSK_LEN);
+       if (key) {
+               os_memcpy(key, data->keymat, EAP_MSK_LEN);
+               *len = EAP_MSK_LEN;
+       }
+
+       return key;
+}
+
+
+static u8 * eap_ikev2_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
+{
+       struct eap_ikev2_data *data = priv;
+       u8 *key;
+
+       if (data->state != DONE || !data->keymat_ok)
+               return NULL;
+
+       key = os_malloc(EAP_EMSK_LEN);
+       if (key) {
+               os_memcpy(key, data->keymat + EAP_MSK_LEN, EAP_EMSK_LEN);
+               *len = EAP_EMSK_LEN;
+       }
+
+       return key;
+}
+
+
+int eap_server_ikev2_register(void)
+{
+       struct eap_method *eap;
+       int ret;
+
+       eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
+                                     EAP_VENDOR_IETF, EAP_TYPE_IKEV2,
+                                     "IKEV2");
+       if (eap == NULL)
+               return -1;
+
+       eap->init = eap_ikev2_init;
+       eap->reset = eap_ikev2_reset;
+       eap->buildReq = eap_ikev2_buildReq;
+       eap->check = eap_ikev2_check;
+       eap->process = eap_ikev2_process;
+       eap->isDone = eap_ikev2_isDone;
+       eap->getKey = eap_ikev2_getKey;
+       eap->isSuccess = eap_ikev2_isSuccess;
+       eap->get_emsk = eap_ikev2_get_emsk;
+
+       ret = eap_server_method_register(eap);
+       if (ret)
+               eap_server_method_free(eap);
+       return ret;
+}