/*
* mschap_authenticate() - authenticate user based on given
* attributes and configuration.
* We will try to find out password in configuration
* or in configured passwd file.
* If one is found we will check paraneters given by NAS.
*
* If PW_SMB_ACCOUNT_CTRL is not set to ACB_PWNOTREQ we must have
* one of:
* PAP: PW_USER_PASSWORD or
* MS-CHAP: PW_MSCHAP_CHALLENGE and PW_MSCHAP_RESPONSE or
* MS-CHAP2: PW_MSCHAP_CHALLENGE and PW_MSCHAP2_RESPONSE
* In case of password mismatch or locked account we MAY return
* PW_MSCHAP_ERROR for MS-CHAP or MS-CHAP v2
* If MS-CHAP2 succeeds we MUST return
* PW_MSCHAP2_SUCCESS
*/
static int mschap_authenticate(void * instance, REQUEST *request)
{
#define inst ((rlm_mschap_t *)instance)
VALUE_PAIR *challenge = NULL;
VALUE_PAIR *response = NULL;
VALUE_PAIR *password = NULL;
VALUE_PAIR *lm_password, *nt_password, *smb_ctrl;
VALUE_PAIR *username;
uint8_t nthashhash[16];
char msch2resp[42];
char *username_string;
int chap = 0;
int do_ntlm_auth;
/*
* If we have ntlm_auth configured, use it unless told
* otherwise
*/
do_ntlm_auth = (inst->ntlm_auth != NULL);
/*
* If we have an ntlm_auth configuration, then we may
* want to suppress it.
*/
if (do_ntlm_auth) {
VALUE_PAIR *vp = pairfind(request->config_items,
PW_MS_CHAP_USE_NTLM_AUTH);
if (vp) do_ntlm_auth = vp->vp_integer;
}
/*
* Find the SMB-Account-Ctrl attribute, or the
* SMB-Account-Ctrl-Text attribute.
*/
smb_ctrl = pairfind(request->config_items, PW_SMB_ACCOUNT_CTRL);
if (!smb_ctrl) {
password = pairfind(request->config_items,
PW_SMB_ACCOUNT_CTRL_TEXT);
if (password) {
smb_ctrl = radius_pairmake(request,
&request->config_items,
"SMB-Account-CTRL", "0",
T_OP_SET);
if (smb_ctrl) {
smb_ctrl->vp_integer = pdb_decode_acct_ctrl(password->vp_strvalue);
}
}
}
/*
* We're configured to do MS-CHAP authentication.
* and account control information exists. Enforce it.
*/
if (smb_ctrl) {
/*
* Password is not required.
*/
if ((smb_ctrl->vp_integer & ACB_PWNOTREQ) != 0) {
RDEBUG2("SMB-Account-Ctrl says no password is required.");
return RLM_MODULE_OK;
}
}
/*
* Decide how to get the passwords.
*/
password = pairfind(request->config_items, PW_CLEARTEXT_PASSWORD);
/*
* We need an LM-Password.
*/
lm_password = pairfind(request->config_items, PW_LM_PASSWORD);
if (lm_password) {
/*
* Allow raw octets.
*/
if ((lm_password->length == 16) ||
((lm_password->length == 32) &&
(fr_hex2bin(lm_password->vp_strvalue,
lm_password->vp_octets, 16) == 16))) {
RDEBUG2("Found LM-Password");
lm_password->length = 16;
} else {
radlog_request(L_ERR, 0, request, "Invalid LM-Password");
lm_password = NULL;
}
} else if (!password) {
if (!do_ntlm_auth) RDEBUG2("No Cleartext-Password configured. Cannot create LM-Password.");
} else { /* there is a configured Cleartext-Password */
lm_password = radius_pairmake(request, &request->config_items,
"LM-Password", "", T_OP_EQ);
if (!lm_password) {
radlog_request(L_ERR, 0, request, "No memory");
} else {
smbdes_lmpwdhash(password->vp_strvalue,
lm_password->vp_octets);
lm_password->length = 16;
}
}
/*
* We need an NT-Password.
*/
nt_password = pairfind(request->config_items, PW_NT_PASSWORD);
if (nt_password) {
if ((nt_password->length == 16) ||
((nt_password->length == 32) &&
(fr_hex2bin(nt_password->vp_strvalue,
nt_password->vp_octets, 16) == 16))) {
RDEBUG2("Found NT-Password");
nt_password->length = 16;
} else {
radlog_request(L_ERR, 0, request, "Invalid NT-Password");
nt_password = NULL;
}
} else if (!password) {
if (!do_ntlm_auth) RDEBUG2("No Cleartext-Password configured. Cannot create NT-Password.");
} else { /* there is a configured Cleartext-Password */
nt_password = radius_pairmake(request, &request->config_items,
"NT-Password", "", T_OP_EQ);
if (!nt_password) {
radlog_request(L_ERR, 0, request, "No memory");
return RLM_MODULE_FAIL;
} else {
mschap_ntpwdhash(nt_password->vp_octets,
password->vp_strvalue);
nt_password->length = 16;
}
}
challenge = pairfind(request->packet->vps, PW_MSCHAP_CHALLENGE);
if (!challenge) {
RDEBUG("ERROR: You set 'Auth-Type = MS-CHAP' for a request that does not contain any MS-CHAP attributes!");
return RLM_MODULE_REJECT;
}
/*
* We also require an MS-CHAP-Response.
*/
response = pairfind(request->packet->vps, PW_MSCHAP_RESPONSE);
/*
* MS-CHAP-Response, means MS-CHAPv1
*/
if (response) {
int offset;
/*
* MS-CHAPv1 challenges are 8 octets.
*/
if (challenge->length < 8) {
radlog_request(L_AUTH, 0, request, "MS-CHAP-Challenge has the wrong format.");
return RLM_MODULE_INVALID;
}
/*
* Responses are 50 octets.
*/
if (response->length < 50) {
radlog_request(L_AUTH, 0, request, "MS-CHAP-Response has the wrong format.");
return RLM_MODULE_INVALID;
}
/*
* We are doing MS-CHAP. Calculate the MS-CHAP
* response
*/
if (response->vp_octets[1] & 0x01) {
RDEBUG2("Client is using MS-CHAPv1 with NT-Password");
password = nt_password;
offset = 26;
} else {
RDEBUG2("Client is using MS-CHAPv1 with LM-Password");
password = lm_password;
offset = 2;
}
/*
* Do the MS-CHAP authentication.
*/
if (do_mschap(inst, request, password, challenge->vp_octets,
response->vp_octets + offset, nthashhash,
do_ntlm_auth) < 0) {
RDEBUG2("MS-CHAP-Response is incorrect.");
goto do_error;
}
chap = 1;
} else if ((response = pairfind(request->packet->vps, PW_MSCHAP2_RESPONSE)) != NULL) {
uint8_t mschapv1_challenge[16];
VALUE_PAIR *name_attr, *response_name;
/*
* MS-CHAPv2 challenges are 16 octets.
*/
if (challenge->length < 16) {
radlog_request(L_AUTH, 0, request, "MS-CHAP-Challenge has the wrong format.");
return RLM_MODULE_INVALID;
}
/*
* Responses are 50 octets.
*/
if (response->length < 50) {
radlog_request(L_AUTH, 0, request, "MS-CHAP-Response has the wrong format.");
return RLM_MODULE_INVALID;
}
/*
* We also require a User-Name
*/
username = pairfind(request->packet->vps, PW_USER_NAME);
if (!username) {
radlog_request(L_AUTH, 0, request, "We require a User-Name for MS-CHAPv2");
return RLM_MODULE_INVALID;
}
/*
* Check for MS-CHAP-User-Name and if found, use it
* to construct the MSCHAPv1 challenge. This is
* set by rlm_eap_mschap to the MS-CHAP Response
* packet Name field.
*
* We prefer this to the User-Name in the
* packet.
*/
response_name = pairfind(request->packet->vps, PW_MS_CHAP_USER_NAME);
if (response_name) {
name_attr = response_name;
} else {
name_attr = username;
}
/*
* with_ntdomain_hack moved here, too.
*/
if ((username_string = strchr(name_attr->vp_strvalue, '\\')) != NULL) {
if (inst->with_ntdomain_hack) {
username_string++;
} else {
RDEBUG2("NT Domain delimeter found, should we have enabled with_ntdomain_hack?");
username_string = name_attr->vp_strvalue;
}
} else {
username_string = name_attr->vp_strvalue;
}
if (response_name &&
((username->length != response_name->length) ||
(strncasecmp(username->vp_strvalue, response_name->vp_strvalue, username->length) != 0))) {
RDEBUG("ERROR: User-Name (%s) is not the same as MS-CHAP Name (%s) from EAP-MSCHAPv2", username->vp_strvalue, response_name->vp_strvalue);
return RLM_MODULE_REJECT;
}
/*
* The old "mschapv2" function has been moved to
* here.
*
* MS-CHAPv2 takes some additional data to create an
* MS-CHAPv1 challenge, and then does MS-CHAPv1.
*/
RDEBUG2("Creating challenge hash with username: %s",
username_string);
mschap_challenge_hash(response->vp_octets + 2, /* peer challenge */
challenge->vp_octets, /* our challenge */
username_string, /* user name */
mschapv1_challenge); /* resulting challenge */
RDEBUG2("Client is using MS-CHAPv2 for %s, we need NT-Password",
username_string);
#ifdef __APPLE__
if (inst->open_directory) {
return do_od_mschap(request, response, challenge, username_string);
}
#endif
if (do_mschap(inst, request, nt_password, mschapv1_challenge,
response->vp_octets + 26, nthashhash,
do_ntlm_auth) < 0) {
int i;
char buffer[128];
RDEBUG2("FAILED: MS-CHAP2-Response is incorrect");
do_error:
snprintf(buffer, sizeof(buffer), "E=691 R=%d",
inst->allow_retry);
if (inst->retry_msg) {
snprintf(buffer + 9, sizeof(buffer) - 9, " C=");
for (i = 0; i < 16; i++) {
snprintf(buffer + 12 + i*2,
sizeof(buffer) - 12 - i*2, "%02x",
fr_rand() & 0xff);
}
snprintf(buffer + 44, sizeof(buffer) - 44,
" V=3 M=%s", inst->retry_msg);
}
mschap_add_reply(request, &request->reply->vps,
*response->vp_octets, "MS-CHAP-Error",
buffer, strlen(buffer));
return RLM_MODULE_REJECT;
}
mschap_auth_response(username_string, /* without the domain */
nthashhash, /* nt-hash-hash */
response->vp_octets + 26, /* peer response */
response->vp_octets + 2, /* peer challenge */
challenge->vp_octets, /* our challenge */
msch2resp); /* calculated MPPE key */
mschap_add_reply(request, &request->reply->vps, *response->vp_octets,
"MS-CHAP2-Success", msch2resp, 42);
chap = 2;
} else { /* Neither CHAPv1 or CHAPv2 response: die */
RDEBUG("ERROR: You set 'Auth-Type = MS-CHAP' for a request that does not contain any MS-CHAP attributes!");
return RLM_MODULE_INVALID;
}
/*
* We have a CHAP response, but the account may be
* disabled. Reject the user with the same error code
* we use when their password is invalid.
*/
if (smb_ctrl) {
/*
* Account is disabled.
*
* They're found, but they don't exist, so we
* return 'not found'.
*/
if (((smb_ctrl->vp_integer & ACB_DISABLED) != 0) ||
((smb_ctrl->vp_integer & (ACB_NORMAL|ACB_WSTRUST)) == 0)) {
RDEBUG2("SMB-Account-Ctrl says that the account is disabled, or is not a normal or workstatin trust account.");
mschap_add_reply(request, &request->reply->vps,
*response->vp_octets,
"MS-CHAP-Error", "E=691 R=1", 9);
return RLM_MODULE_NOTFOUND;
}
/*
* User is locked out.
*/
if ((smb_ctrl->vp_integer & ACB_AUTOLOCK) != 0) {
RDEBUG2("SMB-Account-Ctrl says that the account is locked out.");
mschap_add_reply(request, &request->reply->vps,
*response->vp_octets,
"MS-CHAP-Error", "E=647 R=0", 9);
return RLM_MODULE_USERLOCK;
}
}
/* now create MPPE attributes */
if (inst->use_mppe) {
uint8_t mppe_sendkey[34];
uint8_t mppe_recvkey[34];
if (chap == 1){
RDEBUG2("adding MS-CHAPv1 MPPE keys");
memset(mppe_sendkey, 0, 32);
if (lm_password) {
memcpy(mppe_sendkey, lm_password->vp_octets, 8);
}
/*
* According to RFC 2548 we
* should send NT hash. But in
* practice it doesn't work.
* Instead, we should send nthashhash
*
* This is an error on RFC 2548.
*/
/*
* do_mschap cares to zero nthashhash if NT hash
* is not available.
*/
memcpy(mppe_sendkey + 8,
nthashhash, 16);
mppe_add_reply(request,
"MS-CHAP-MPPE-Keys",
mppe_sendkey, 32);
} else if (chap == 2) {
RDEBUG2("adding MS-CHAPv2 MPPE keys");
mppe_chap2_gen_keys128(nthashhash,
response->vp_octets + 26,
mppe_sendkey, mppe_recvkey);
mppe_add_reply(request,
"MS-MPPE-Recv-Key",
mppe_recvkey, 16);
mppe_add_reply(request,
"MS-MPPE-Send-Key",
mppe_sendkey, 16);
}
radius_pairmake(request, &request->reply->vps,
"MS-MPPE-Encryption-Policy",
(inst->require_encryption)? "0x00000002":"0x00000001",
T_OP_EQ);
radius_pairmake(request, &request->reply->vps,
"MS-MPPE-Encryption-Types",
(inst->require_strong)? "0x00000004":"0x00000006",
T_OP_EQ);
} /* else we weren't asked to use MPPE */
return RLM_MODULE_OK;
#undef inst
}
int
eap_mschap(struct iked *env, struct iked_sa *sa, struct eap_message *eap)
{
struct iked_user *usr;
struct eap_message *resp;
struct eap_mschap_response *msr;
struct eap_mschap_peer *msp;
struct eap_mschap *ms;
struct eap_mschap_success *mss;
u_int8_t *ptr, *pass;
size_t len, passlen;
char *name, *msg;
u_int8_t ntresponse[EAP_MSCHAP_NTRESPONSE_SZ];
u_int8_t successmsg[EAP_MSCHAP_SUCCESS_SZ];
struct ibuf *eapmsg = NULL;
int ret = -1;
if (!sa_stateok(sa, IKEV2_STATE_EAP)) {
log_debug("%s: unexpected EAP", __func__);
return (0); /* ignore */
}
if (sa->sa_hdr.sh_initiator) {
log_debug("%s: initiator EAP not supported", __func__);
return (-1);
}
/* Only MSCHAP-V2 */
if (eap->eap_type != EAP_TYPE_MSCHAP_V2) {
log_debug("%s: unsupported type EAP-%s", __func__,
print_map(eap->eap_type, eap_type_map));
return (-1);
}
if (betoh16(eap->eap_length) < (sizeof(*eap) + sizeof(*ms))) {
log_debug("%s: short message", __func__);
return (-1);
}
ms = (struct eap_mschap *)(eap + 1);
ptr = (u_int8_t *)(eap + 1);
switch (ms->ms_opcode) {
case EAP_MSOPCODE_RESPONSE:
msr = (struct eap_mschap_response *)ms;
if (betoh16(eap->eap_length) < (sizeof(*eap) + sizeof(*msr))) {
log_debug("%s: short response", __func__);
return (-1);
}
ptr += sizeof(*msr);
len = betoh16(eap->eap_length) -
sizeof(*eap) - sizeof(*msr);
if (len == 0 && sa->sa_eapid != NULL)
name = strdup(sa->sa_eapid);
else
name = get_string(ptr, len);
if (name == NULL) {
log_debug("%s: invalid response name", __func__);
return (-1);
}
if ((usr = user_lookup(env, name)) == NULL) {
log_debug("%s: unknown user '%s'", __func__, name);
free(name);
return (-1);
}
free(name);
if ((pass = string2unicode(usr->usr_pass, &passlen)) == NULL)
return (-1);
msp = &msr->msr_response.resp_peer;
mschap_nt_response(ibuf_data(sa->sa_eap.id_buf),
msp->msp_challenge, usr->usr_name, strlen(usr->usr_name),
pass, passlen, ntresponse);
if (memcmp(ntresponse, msp->msp_ntresponse,
sizeof(ntresponse)) != 0) {
log_debug("%s: '%s' authentication failed", __func__,
usr->usr_name);
free(pass);
/* XXX should we send an EAP failure packet? */
return (-1);
}
bzero(&successmsg, sizeof(successmsg));
mschap_auth_response(pass, passlen,
ntresponse, ibuf_data(sa->sa_eap.id_buf),
msp->msp_challenge, usr->usr_name, strlen(usr->usr_name),
successmsg);
if ((sa->sa_eapmsk = ibuf_new(NULL, MSCHAP_MSK_SZ)) == NULL) {
log_debug("%s: failed to get MSK", __func__);
free(pass);
return (-1);
}
mschap_msk(pass, passlen, ntresponse,
ibuf_data(sa->sa_eapmsk));
free(pass);
log_info("%s: '%s' authenticated", __func__, usr->usr_name);
if ((eapmsg = ibuf_static()) == NULL)
return (-1);
msg = " M=Welcome";
if ((resp = ibuf_advance(eapmsg, sizeof(*resp))) == NULL)
goto done;
resp->eap_code = EAP_CODE_REQUEST;
resp->eap_id = eap->eap_id + 1;
resp->eap_length = htobe16(sizeof(*resp) + sizeof(*mss) +
sizeof(successmsg) + strlen(msg));
resp->eap_type = EAP_TYPE_MSCHAP_V2;
if ((mss = ibuf_advance(eapmsg, sizeof(*mss))) == NULL)
goto done;
mss->mss_opcode = EAP_MSOPCODE_SUCCESS;
mss->mss_id = msr->msr_id;
mss->mss_length = htobe16(sizeof(*mss) +
sizeof(successmsg) + strlen(msg));
if (ibuf_add(eapmsg, successmsg, sizeof(successmsg)) != 0)
goto done;
if (ibuf_add(eapmsg, msg, strlen(msg)) != 0)
goto done;
break;
case EAP_MSOPCODE_SUCCESS:
if ((eapmsg = ibuf_static()) == NULL)
return (-1);
if ((resp = ibuf_advance(eapmsg, sizeof(*resp))) == NULL)
goto done;
resp->eap_code = EAP_CODE_RESPONSE;
resp->eap_id = eap->eap_id;
resp->eap_length = htobe16(sizeof(*resp) + sizeof(*ms));
resp->eap_type = EAP_TYPE_MSCHAP_V2;
if ((ms = ibuf_advance(eapmsg, sizeof(*ms))) == NULL)
goto done;
ms->ms_opcode = EAP_MSOPCODE_SUCCESS;
break;
case EAP_MSOPCODE_FAILURE:
case EAP_MSOPCODE_CHANGE_PASSWORD:
case EAP_MSOPCODE_CHALLENGE:
default:
log_debug("%s: EAP-%s unsupported "
"responder operation %s", __func__,
print_map(eap->eap_type, eap_type_map),
print_map(ms->ms_opcode, eap_msopcode_map));
return (-1);
}
if (eapmsg != NULL)
ret = ikev2_send_ike_e(env, sa, eapmsg,
IKEV2_PAYLOAD_EAP, IKEV2_EXCHANGE_IKE_AUTH, 1);
if (ret == 0)
sa_state(env, sa, IKEV2_STATE_AUTH_SUCCESS);
done:
ibuf_release(eapmsg);
return (ret);
}
static void
mschapv2_authenticate(chap *_this, int id, char *username, u_char *challenge,
int lchallenge, u_char *response)
{
int i, rval, passlen, lpkt;
u_char *pkt;
char password[MAX_PASSWORD_LENGTH * 2], ntresponse[24];
#ifdef USE_NPPPD_MPPE
char pwdhash[16], pwdhashhash[16];
#endif
CHAP_DBG((_this, LOG_DEBUG, "%s()", __func__));
pkt = ppp_packetbuf(_this->ppp, PPP_PROTO_CHAP) + HEADERLEN;
lpkt = _this->ppp->mru - HEADERLEN;
passlen = sizeof(password) / 2;
rval = npppd_get_user_password(_this->ppp->pppd, _this->ppp, username,
password, &passlen);
if (rval != 0) {
switch (rval) {
case 1:
chap_log(_this, LOG_INFO,
"username=\"%s\" user unknown", username);
break;
default:
chap_log(_this, LOG_ERR,
"username=\"%s\" generic error", username);
break;
}
goto auth_failed;
}
/* Convert the string charset from ASCII to UTF16-LE */
passlen = strlen(password);
for (i = passlen - 1; i >= 0; i--) {
password[i*2] = password[i];
password[i*2+1] = 0;
}
mschap_nt_response(challenge, response, username, strlen(username),
password, passlen * 2, ntresponse);
if (memcmp(ntresponse, response + 24, 24) != 0) {
chap_log(_this, LOG_INFO,
"username=\"%s\" password mismatch.", username);
goto auth_failed;
}
/*
* Authentication succeed
*/
CHAP_DBG((_this, LOG_DEBUG, "%s() OK", __func__));
mschap_auth_response(password, passlen * 2, ntresponse,
challenge, response, username, strlen(username), pkt);
lpkt = 42;
#ifdef USE_NPPPD_MPPE
if (_this->ppp->mppe.enabled != 0) {
mschap_ntpassword_hash(password, passlen * 2, pwdhash);
mschap_ntpassword_hash(pwdhash, sizeof(pwdhash), pwdhashhash);
mschap_masterkey(pwdhashhash, ntresponse,
_this->ppp->mppe.master_key);
mschap_asymetric_startkey(_this->ppp->mppe.master_key,
_this->ppp->mppe.recv.master_key, MPPE_KEYLEN, 0, 1);
mschap_asymetric_startkey(_this->ppp->mppe.master_key,
_this->ppp->mppe.send.master_key, MPPE_KEYLEN, 1, 1);
}
#endif
chap_response(_this, 1, pkt, lpkt);
return;
auth_failed:
/* No extra information */
mschapv2_send_error(_this, ERROR_AUTHENTICATION_FAILURE, 0);
return;
}