aboutsummaryrefslogtreecommitdiffstats
path: root/src/eap_server/eap_server_tnc.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/eap_server/eap_server_tnc.c')
-rw-r--r--src/eap_server/eap_server_tnc.c548
1 files changed, 548 insertions, 0 deletions
diff --git a/src/eap_server/eap_server_tnc.c b/src/eap_server/eap_server_tnc.c
new file mode 100644
index 0000000..b4fd495
--- /dev/null
+++ b/src/eap_server/eap_server_tnc.c
@@ -0,0 +1,548 @@
+/*
+ * EAP server method: EAP-TNC (Trusted Network Connect)
+ * Copyright (c) 2007-2010, 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 "base64.h"
+#include "eap_i.h"
+#include "tncs.h"
+
+
+struct eap_tnc_data {
+ enum { START, CONTINUE, RECOMMENDATION, FRAG_ACK, WAIT_FRAG_ACK, DONE,
+ FAIL } state;
+ enum { ALLOW, ISOLATE, NO_ACCESS, NO_RECOMMENDATION } recommendation;
+ struct tncs_data *tncs;
+ struct wpabuf *in_buf;
+ struct wpabuf *out_buf;
+ size_t out_used;
+ size_t fragment_size;
+ int was_done:1;
+ int was_fail:1;
+};
+
+
+/* EAP-TNC Flags */
+#define EAP_TNC_FLAGS_LENGTH_INCLUDED 0x80
+#define EAP_TNC_FLAGS_MORE_FRAGMENTS 0x40
+#define EAP_TNC_FLAGS_START 0x20
+#define EAP_TNC_VERSION_MASK 0x07
+
+#define EAP_TNC_VERSION 1
+
+
+static void * eap_tnc_init(struct eap_sm *sm)
+{
+ struct eap_tnc_data *data;
+
+ data = os_zalloc(sizeof(*data));
+ if (data == NULL)
+ return NULL;
+ data->state = START;
+ data->tncs = tncs_init();
+ if (data->tncs == NULL) {
+ os_free(data);
+ return NULL;
+ }
+
+ data->fragment_size = 1300;
+
+ return data;
+}
+
+
+static void eap_tnc_reset(struct eap_sm *sm, void *priv)
+{
+ struct eap_tnc_data *data = priv;
+ wpabuf_free(data->in_buf);
+ wpabuf_free(data->out_buf);
+ tncs_deinit(data->tncs);
+ os_free(data);
+}
+
+
+static struct wpabuf * eap_tnc_build_start(struct eap_sm *sm,
+ struct eap_tnc_data *data, u8 id)
+{
+ struct wpabuf *req;
+
+ req = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_TNC, 1, EAP_CODE_REQUEST,
+ id);
+ if (req == NULL) {
+ wpa_printf(MSG_ERROR, "EAP-TNC: Failed to allocate memory for "
+ "request");
+ data->state = FAIL;
+ return NULL;
+ }
+
+ wpabuf_put_u8(req, EAP_TNC_FLAGS_START | EAP_TNC_VERSION);
+
+ data->state = CONTINUE;
+
+ return req;
+}
+
+
+static struct wpabuf * eap_tnc_build(struct eap_sm *sm,
+ struct eap_tnc_data *data)
+{
+ struct wpabuf *req;
+ u8 *rpos, *rpos1;
+ size_t rlen;
+ char *start_buf, *end_buf;
+ size_t start_len, end_len;
+ size_t imv_len;
+
+ imv_len = tncs_total_send_len(data->tncs);
+
+ start_buf = tncs_if_tnccs_start(data->tncs);
+ if (start_buf == NULL)
+ return NULL;
+ start_len = os_strlen(start_buf);
+ end_buf = tncs_if_tnccs_end();
+ if (end_buf == NULL) {
+ os_free(start_buf);
+ return NULL;
+ }
+ end_len = os_strlen(end_buf);
+
+ rlen = start_len + imv_len + end_len;
+ req = wpabuf_alloc(rlen);
+ if (req == NULL) {
+ os_free(start_buf);
+ os_free(end_buf);
+ return NULL;
+ }
+
+ wpabuf_put_data(req, start_buf, start_len);
+ os_free(start_buf);
+
+ rpos1 = wpabuf_put(req, 0);
+ rpos = tncs_copy_send_buf(data->tncs, rpos1);
+ wpabuf_put(req, rpos - rpos1);
+
+ wpabuf_put_data(req, end_buf, end_len);
+ os_free(end_buf);
+
+ wpa_hexdump_ascii(MSG_MSGDUMP, "EAP-TNC: Request",
+ wpabuf_head(req), wpabuf_len(req));
+
+ return req;
+}
+
+
+static struct wpabuf * eap_tnc_build_recommendation(struct eap_sm *sm,
+ struct eap_tnc_data *data)
+{
+ switch (data->recommendation) {
+ case ALLOW:
+ data->state = DONE;
+ break;
+ case ISOLATE:
+ data->state = FAIL;
+ /* TODO: support assignment to a different VLAN */
+ break;
+ case NO_ACCESS:
+ data->state = FAIL;
+ break;
+ case NO_RECOMMENDATION:
+ data->state = DONE;
+ break;
+ default:
+ wpa_printf(MSG_DEBUG, "EAP-TNC: Unknown recommendation");
+ return NULL;
+ }
+
+ return eap_tnc_build(sm, data);
+}
+
+
+static struct wpabuf * eap_tnc_build_frag_ack(u8 id, u8 code)
+{
+ struct wpabuf *msg;
+
+ msg = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_TNC, 1, code, id);
+ if (msg == NULL) {
+ wpa_printf(MSG_ERROR, "EAP-TNC: Failed to allocate memory "
+ "for fragment ack");
+ return NULL;
+ }
+ wpabuf_put_u8(msg, EAP_TNC_VERSION); /* Flags */
+
+ wpa_printf(MSG_DEBUG, "EAP-TNC: Send fragment ack");
+
+ return msg;
+}
+
+
+static struct wpabuf * eap_tnc_build_msg(struct eap_tnc_data *data, u8 id)
+{
+ struct wpabuf *req;
+ u8 flags;
+ size_t send_len, plen;
+
+ wpa_printf(MSG_DEBUG, "EAP-TNC: Generating Request");
+
+ flags = EAP_TNC_VERSION;
+ send_len = wpabuf_len(data->out_buf) - data->out_used;
+ if (1 + send_len > data->fragment_size) {
+ send_len = data->fragment_size - 1;
+ flags |= EAP_TNC_FLAGS_MORE_FRAGMENTS;
+ if (data->out_used == 0) {
+ flags |= EAP_TNC_FLAGS_LENGTH_INCLUDED;
+ send_len -= 4;
+ }
+ }
+
+ plen = 1 + send_len;
+ if (flags & EAP_TNC_FLAGS_LENGTH_INCLUDED)
+ plen += 4;
+ req = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_TNC, plen,
+ EAP_CODE_REQUEST, id);
+ if (req == NULL)
+ return NULL;
+
+ wpabuf_put_u8(req, flags); /* Flags */
+ if (flags & EAP_TNC_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 (data->out_used == wpabuf_len(data->out_buf)) {
+ wpa_printf(MSG_DEBUG, "EAP-TNC: 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-TNC: Sending out %lu bytes "
+ "(%lu more to send)", (unsigned long) send_len,
+ (unsigned long) wpabuf_len(data->out_buf) -
+ data->out_used);
+ if (data->state == FAIL)
+ data->was_fail = 1;
+ else if (data->state == DONE)
+ data->was_done = 1;
+ data->state = WAIT_FRAG_ACK;
+ }
+
+ return req;
+}
+
+
+static struct wpabuf * eap_tnc_buildReq(struct eap_sm *sm, void *priv, u8 id)
+{
+ struct eap_tnc_data *data = priv;
+
+ switch (data->state) {
+ case START:
+ tncs_init_connection(data->tncs);
+ return eap_tnc_build_start(sm, data, id);
+ case CONTINUE:
+ if (data->out_buf == NULL) {
+ data->out_buf = eap_tnc_build(sm, data);
+ if (data->out_buf == NULL) {
+ wpa_printf(MSG_DEBUG, "EAP-TNC: Failed to "
+ "generate message");
+ return NULL;
+ }
+ data->out_used = 0;
+ }
+ return eap_tnc_build_msg(data, id);
+ case RECOMMENDATION:
+ if (data->out_buf == NULL) {
+ data->out_buf = eap_tnc_build_recommendation(sm, data);
+ if (data->out_buf == NULL) {
+ wpa_printf(MSG_DEBUG, "EAP-TNC: Failed to "
+ "generate recommendation message");
+ return NULL;
+ }
+ data->out_used = 0;
+ }
+ return eap_tnc_build_msg(data, id);
+ case WAIT_FRAG_ACK:
+ return eap_tnc_build_msg(data, id);
+ case FRAG_ACK:
+ return eap_tnc_build_frag_ack(id, EAP_CODE_REQUEST);
+ case DONE:
+ case FAIL:
+ return NULL;
+ }
+
+ return NULL;
+}
+
+
+static Boolean eap_tnc_check(struct eap_sm *sm, void *priv,
+ struct wpabuf *respData)
+{
+ struct eap_tnc_data *data = priv;
+ const u8 *pos;
+ size_t len;
+
+ pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_TNC, respData,
+ &len);
+ if (pos == NULL) {
+ wpa_printf(MSG_INFO, "EAP-TNC: Invalid frame");
+ return TRUE;
+ }
+
+ if (len == 0 && data->state != WAIT_FRAG_ACK) {
+ wpa_printf(MSG_INFO, "EAP-TNC: Invalid frame (empty)");
+ return TRUE;
+ }
+
+ if (len == 0)
+ return FALSE; /* Fragment ACK does not include flags */
+
+ if ((*pos & EAP_TNC_VERSION_MASK) != EAP_TNC_VERSION) {
+ wpa_printf(MSG_DEBUG, "EAP-TNC: Unsupported version %d",
+ *pos & EAP_TNC_VERSION_MASK);
+ return TRUE;
+ }
+
+ if (*pos & EAP_TNC_FLAGS_START) {
+ wpa_printf(MSG_DEBUG, "EAP-TNC: Peer used Start flag");
+ return TRUE;
+ }
+
+ return FALSE;
+}
+
+
+static void tncs_process(struct eap_tnc_data *data, struct wpabuf *inbuf)
+{
+ enum tncs_process_res res;
+
+ res = tncs_process_if_tnccs(data->tncs, wpabuf_head(inbuf),
+ wpabuf_len(inbuf));
+ switch (res) {
+ case TNCCS_RECOMMENDATION_ALLOW:
+ wpa_printf(MSG_DEBUG, "EAP-TNC: TNCS allowed access");
+ data->state = RECOMMENDATION;
+ data->recommendation = ALLOW;
+ break;
+ case TNCCS_RECOMMENDATION_NO_RECOMMENDATION:
+ wpa_printf(MSG_DEBUG, "EAP-TNC: TNCS has no recommendation");
+ data->state = RECOMMENDATION;
+ data->recommendation = NO_RECOMMENDATION;
+ break;
+ case TNCCS_RECOMMENDATION_ISOLATE:
+ wpa_printf(MSG_DEBUG, "EAP-TNC: TNCS requested isolation");
+ data->state = RECOMMENDATION;
+ data->recommendation = ISOLATE;
+ break;
+ case TNCCS_RECOMMENDATION_NO_ACCESS:
+ wpa_printf(MSG_DEBUG, "EAP-TNC: TNCS rejected access");
+ data->state = RECOMMENDATION;
+ data->recommendation = NO_ACCESS;
+ break;
+ case TNCCS_PROCESS_ERROR:
+ wpa_printf(MSG_DEBUG, "EAP-TNC: TNCS processing error");
+ data->state = FAIL;
+ break;
+ default:
+ break;
+ }
+}
+
+
+static int eap_tnc_process_cont(struct eap_tnc_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-TNC: Fragment overflow");
+ data->state = FAIL;
+ return -1;
+ }
+
+ wpabuf_put_data(data->in_buf, buf, len);
+ wpa_printf(MSG_DEBUG, "EAP-TNC: Received %lu bytes, waiting for %lu "
+ "bytes more", (unsigned long) len,
+ (unsigned long) wpabuf_tailroom(data->in_buf));
+
+ return 0;
+}
+
+
+static int eap_tnc_process_fragment(struct eap_tnc_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 & EAP_TNC_FLAGS_LENGTH_INCLUDED)) {
+ wpa_printf(MSG_DEBUG, "EAP-TNC: 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-TNC: No memory for "
+ "message");
+ return -1;
+ }
+ wpabuf_put_data(data->in_buf, buf, len);
+ wpa_printf(MSG_DEBUG, "EAP-TNC: Received %lu bytes in first "
+ "fragment, waiting for %lu bytes more",
+ (unsigned long) len,
+ (unsigned long) wpabuf_tailroom(data->in_buf));
+ }
+
+ return 0;
+}
+
+
+static void eap_tnc_process(struct eap_sm *sm, void *priv,
+ struct wpabuf *respData)
+{
+ struct eap_tnc_data *data = priv;
+ const u8 *pos, *end;
+ size_t len;
+ u8 flags;
+ u32 message_length = 0;
+ struct wpabuf tmpbuf;
+
+ pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_TNC, respData, &len);
+ if (pos == NULL)
+ return; /* Should not happen; message already verified */
+
+ end = pos + len;
+
+ if (len == 1 && (data->state == DONE || data->state == FAIL)) {
+ wpa_printf(MSG_DEBUG, "EAP-TNC: Peer acknowledged the last "
+ "message");
+ return;
+ }
+
+ if (len == 0) {
+ /* fragment ack */
+ flags = 0;
+ } else
+ flags = *pos++;
+
+ if (flags & EAP_TNC_FLAGS_LENGTH_INCLUDED) {
+ if (end - pos < 4) {
+ wpa_printf(MSG_DEBUG, "EAP-TNC: Message underflow");
+ data->state = FAIL;
+ return;
+ }
+ message_length = WPA_GET_BE32(pos);
+ pos += 4;
+
+ if (message_length < (u32) (end - pos)) {
+ wpa_printf(MSG_DEBUG, "EAP-TNC: Invalid Message "
+ "Length (%d; %ld remaining in this msg)",
+ message_length, (long) (end - pos));
+ data->state = FAIL;
+ return;
+ }
+ }
+ wpa_printf(MSG_DEBUG, "EAP-TNC: Received packet: Flags 0x%x "
+ "Message Length %u", flags, message_length);
+
+ if (data->state == WAIT_FRAG_ACK) {
+ if (len > 1) {
+ wpa_printf(MSG_DEBUG, "EAP-TNC: Unexpected payload "
+ "in WAIT_FRAG_ACK state");
+ data->state = FAIL;
+ return;
+ }
+ wpa_printf(MSG_DEBUG, "EAP-TNC: Fragment acknowledged");
+ if (data->was_fail)
+ data->state = FAIL;
+ else if (data->was_done)
+ data->state = DONE;
+ else
+ data->state = CONTINUE;
+ return;
+ }
+
+ if (data->in_buf && eap_tnc_process_cont(data, pos, end - pos) < 0) {
+ data->state = FAIL;
+ return;
+ }
+
+ if (flags & EAP_TNC_FLAGS_MORE_FRAGMENTS) {
+ if (eap_tnc_process_fragment(data, flags, message_length,
+ pos, end - pos) < 0)
+ data->state = FAIL;
+ else
+ data->state = FRAG_ACK;
+ return;
+ } else if (data->state == FRAG_ACK) {
+ wpa_printf(MSG_DEBUG, "EAP-TNC: All fragments received");
+ data->state = CONTINUE;
+ }
+
+ if (data->in_buf == NULL) {
+ /* Wrap unfragmented messages as wpabuf without extra copy */
+ wpabuf_set(&tmpbuf, pos, end - pos);
+ data->in_buf = &tmpbuf;
+ }
+
+ wpa_hexdump_ascii(MSG_MSGDUMP, "EAP-TNC: Received payload",
+ wpabuf_head(data->in_buf), wpabuf_len(data->in_buf));
+ tncs_process(data, data->in_buf);
+
+ if (data->in_buf != &tmpbuf)
+ wpabuf_free(data->in_buf);
+ data->in_buf = NULL;
+}
+
+
+static Boolean eap_tnc_isDone(struct eap_sm *sm, void *priv)
+{
+ struct eap_tnc_data *data = priv;
+ return data->state == DONE || data->state == FAIL;
+}
+
+
+static Boolean eap_tnc_isSuccess(struct eap_sm *sm, void *priv)
+{
+ struct eap_tnc_data *data = priv;
+ return data->state == DONE;
+}
+
+
+int eap_server_tnc_register(void)
+{
+ struct eap_method *eap;
+ int ret;
+
+ eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
+ EAP_VENDOR_IETF, EAP_TYPE_TNC, "TNC");
+ if (eap == NULL)
+ return -1;
+
+ eap->init = eap_tnc_init;
+ eap->reset = eap_tnc_reset;
+ eap->buildReq = eap_tnc_buildReq;
+ eap->check = eap_tnc_check;
+ eap->process = eap_tnc_process;
+ eap->isDone = eap_tnc_isDone;
+ eap->isSuccess = eap_tnc_isSuccess;
+
+ ret = eap_server_method_register(eap);
+ if (ret)
+ eap_server_method_free(eap);
+ return ret;
+}