/**
* eap_mschapv2_process - Process an EAP-MSCHAPv2 challenge message
* @sm: Pointer to EAP state machine allocated with eap_peer_sm_init()
* @data: Pointer to private EAP method data from eap_mschapv2_init()
* @ret: Return values from EAP request validation and processing
* @req: Pointer to EAP-MSCHAPv2 header from the request
* @req_len: Length of the EAP-MSCHAPv2 data
* @id: EAP identifier used in the request
* Returns: Pointer to allocated EAP response packet (eapRespData) or %NULL if
* no reply available
*/
static struct wpabuf * eap_mschapv2_challenge(
struct eap_sm *sm, struct eap_mschapv2_data *data,
struct eap_method_ret *ret, const struct eap_mschapv2_hdr *req,
size_t req_len, u8 id)
{
size_t len, challenge_len;
const u8 *pos, *challenge;
if (eap_get_config_identity(sm, &len) == NULL ||
eap_get_config_password(sm, &len) == NULL)
return NULL;
wpa_printf(MSG_DEBUG, "EAP-MSCHAPV2: Received challenge");
if (req_len < sizeof(*req) + 1) {
wpa_printf(MSG_INFO, "EAP-MSCHAPV2: Too short challenge data "
"(len %lu)", (unsigned long) req_len);
ret->ignore = TRUE;
return NULL;
}
pos = (const u8 *) (req + 1);
challenge_len = *pos++;
len = req_len - sizeof(*req) - 1;
if (challenge_len != MSCHAPV2_CHAL_LEN) {
wpa_printf(MSG_INFO, "EAP-MSCHAPV2: Invalid challenge length "
"%lu", (unsigned long) challenge_len);
ret->ignore = TRUE;
return NULL;
}
if (len < challenge_len) {
wpa_printf(MSG_INFO, "EAP-MSCHAPV2: Too short challenge"
" packet: len=%lu challenge_len=%lu",
(unsigned long) len, (unsigned long) challenge_len);
ret->ignore = TRUE;
return NULL;
}
if (data->passwd_change_challenge_valid) {
wpa_printf(MSG_DEBUG, "EAP-MSCHAPV2: Using challenge from the "
"failure message");
challenge = data->passwd_change_challenge;
} else
challenge = pos;
pos += challenge_len;
len -= challenge_len;
wpa_hexdump_ascii(MSG_DEBUG, "EAP-MSCHAPV2: Authentication Servername",
pos, len);
ret->ignore = FALSE;
ret->methodState = METHOD_MAY_CONT;
ret->decision = DECISION_FAIL;
ret->allowNotifications = TRUE;
return eap_mschapv2_challenge_reply(sm, data, id, req->mschapv2_id,
challenge);
}
static struct wpabuf *
eap_mschapv2_challenge(
struct eap_sm *sm, struct eap_mschapv2_data *data,
struct eap_method_ret *ret, const struct eap_mschapv2_hdr *req,
size_t req_len, u8 id)
{
size_t len, challenge_len;
const u8 *pos, *challenge;
if (eap_get_config_identity(sm, &len) == NULL ||
eap_get_config_password(sm, &len) == NULL)
return NULL;
if (req_len < sizeof(*req) + 1) {
ret->ignore = true;
return NULL;
}
pos = (const u8 *)(req + 1);
challenge_len = *pos++;
len = req_len - sizeof(*req) - 1;
if (challenge_len != MSCHAPV2_CHAL_LEN) {
ret->ignore = true;
return NULL;
}
if (len < challenge_len) {
ret->ignore = true;
return NULL;
}
if (data->passwd_change_challenge_valid)
challenge = data->passwd_change_challenge;
else
challenge = pos;
pos += challenge_len;
len -= challenge_len;
ret->ignore = false;
ret->methodState = METHOD_MAY_CONT;
ret->decision = DECISION_FAIL;
ret->allowNotifications = true;
return eap_mschapv2_challenge_reply(sm, data, id, req->mschapv2_id,
challenge);
}
