hostap/src/eap_server/eap_server_tnc.c
Jouni Malinen 997de7aa5c Remove unnecessary base64.h inclusion
All the TNC base64 operations are within tncs.c, so there is no point in
including base64.h into eap_server_tnc.c.

Signed-hostap: Jouni Malinen <j@w1.fi>
2012-08-19 18:41:45 +03:00

575 lines
14 KiB
C

/*
* EAP server method: EAP-TNC (Trusted Network Connect)
* Copyright (c) 2007-2010, Jouni Malinen <j@w1.fi>
*
* This software may be distributed under the terms of the BSD license.
* See README for more details.
*/
#include "includes.h"
#include "common.h"
#include "eap_i.h"
#include "tncs.h"
struct eap_tnc_data {
enum eap_tnc_state {
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;
unsigned int was_done:1;
unsigned 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 const char * eap_tnc_state_txt(enum eap_tnc_state state)
{
switch (state) {
case START:
return "START";
case CONTINUE:
return "CONTINUE";
case RECOMMENDATION:
return "RECOMMENDATION";
case FRAG_ACK:
return "FRAG_ACK";
case WAIT_FRAG_ACK:
return "WAIT_FRAG_ACK";
case DONE:
return "DONE";
case FAIL:
return "FAIL";
}
return "??";
}
static void eap_tnc_set_state(struct eap_tnc_data *data,
enum eap_tnc_state new_state)
{
wpa_printf(MSG_DEBUG, "EAP-TNC: %s -> %s",
eap_tnc_state_txt(data->state),
eap_tnc_state_txt(new_state));
data->state = new_state;
}
static void * eap_tnc_init(struct eap_sm *sm)
{
struct eap_tnc_data *data;
data = os_zalloc(sizeof(*data));
if (data == NULL)
return NULL;
eap_tnc_set_state(data, START);
data->tncs = tncs_init();
if (data->tncs == NULL) {
os_free(data);
return NULL;
}
data->fragment_size = sm->fragment_size > 100 ?
sm->fragment_size - 98 : 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");
eap_tnc_set_state(data, FAIL);
return NULL;
}
wpabuf_put_u8(req, EAP_TNC_FLAGS_START | EAP_TNC_VERSION);
eap_tnc_set_state(data, 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:
eap_tnc_set_state(data, DONE);
break;
case ISOLATE:
eap_tnc_set_state(data, FAIL);
/* TODO: support assignment to a different VLAN */
break;
case NO_ACCESS:
eap_tnc_set_state(data, FAIL);
break;
case NO_RECOMMENDATION:
eap_tnc_set_state(data, 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;
if (data->was_fail)
eap_tnc_set_state(data, FAIL);
else if (data->was_done)
eap_tnc_set_state(data, DONE);
} 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;
eap_tnc_set_state(data, 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");
eap_tnc_set_state(data, RECOMMENDATION);
data->recommendation = ALLOW;
break;
case TNCCS_RECOMMENDATION_NO_RECOMMENDATION:
wpa_printf(MSG_DEBUG, "EAP-TNC: TNCS has no recommendation");
eap_tnc_set_state(data, RECOMMENDATION);
data->recommendation = NO_RECOMMENDATION;
break;
case TNCCS_RECOMMENDATION_ISOLATE:
wpa_printf(MSG_DEBUG, "EAP-TNC: TNCS requested isolation");
eap_tnc_set_state(data, RECOMMENDATION);
data->recommendation = ISOLATE;
break;
case TNCCS_RECOMMENDATION_NO_ACCESS:
wpa_printf(MSG_DEBUG, "EAP-TNC: TNCS rejected access");
eap_tnc_set_state(data, RECOMMENDATION);
data->recommendation = NO_ACCESS;
break;
case TNCCS_PROCESS_ERROR:
wpa_printf(MSG_DEBUG, "EAP-TNC: TNCS processing error");
eap_tnc_set_state(data, 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");
eap_tnc_set_state(data, 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");
eap_tnc_set_state(data, 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));
eap_tnc_set_state(data, 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");
eap_tnc_set_state(data, FAIL);
return;
}
wpa_printf(MSG_DEBUG, "EAP-TNC: Fragment acknowledged");
eap_tnc_set_state(data, CONTINUE);
return;
}
if (data->in_buf && eap_tnc_process_cont(data, pos, end - pos) < 0) {
eap_tnc_set_state(data, FAIL);
return;
}
if (flags & EAP_TNC_FLAGS_MORE_FRAGMENTS) {
if (eap_tnc_process_fragment(data, flags, message_length,
pos, end - pos) < 0)
eap_tnc_set_state(data, FAIL);
else
eap_tnc_set_state(data, FRAG_ACK);
return;
} else if (data->state == FRAG_ACK) {
wpa_printf(MSG_DEBUG, "EAP-TNC: All fragments received");
eap_tnc_set_state(data, 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;
}