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|
#include <stdlib.h>
#include <string.h>
#include <openssl/md5.h>
#include <openssl/sha.h>
#include "triton.h"
#include "events.h"
#include "log.h"
#include "pwdb.h"
#include "radius_p.h"
#include "attr_defs.h"
#include "memdebug.h"
static int decrypt_chap_mppe_keys(struct rad_req_t *req, struct rad_attr_t *attr, const uint8_t *challenge, uint8_t *key)
{
MD5_CTX md5_ctx;
SHA_CTX sha1_ctx;
uint8_t md5[MD5_DIGEST_LENGTH];
uint8_t sha1[SHA_DIGEST_LENGTH];
uint8_t plain[32];
int i;
if (attr->len != 32) {
log_ppp_warn("radius: %s: incorrect attribute length (%i)\n", attr->attr->name, attr->len);
return -1;
}
memcpy(plain, attr->val.octets, 32);
MD5_Init(&md5_ctx);
MD5_Update(&md5_ctx, conf_auth_secret, strlen(conf_auth_secret));
MD5_Update(&md5_ctx, req->pack->buf + 4, 16);
MD5_Final(md5, &md5_ctx);
for (i = 0; i < 16; i++)
plain[i] ^= md5[i];
MD5_Init(&md5_ctx);
MD5_Update(&md5_ctx, conf_auth_secret, strlen(conf_auth_secret));
MD5_Update(&md5_ctx, attr->val.octets, 16);
MD5_Final(md5, &md5_ctx);
for (i = 0; i < 16; i++)
plain[i + 16] ^= md5[i];
SHA1_Init(&sha1_ctx);
SHA1_Update(&sha1_ctx, plain + 8, 16);
SHA1_Update(&sha1_ctx, plain + 8, 16);
SHA1_Update(&sha1_ctx, challenge, 8);
SHA1_Final(sha1, &sha1_ctx);
memcpy(key, sha1, 16);
return 0;
}
static int decrypt_mppe_key(struct rad_req_t *req, struct rad_attr_t *attr, uint8_t *key)
{
MD5_CTX md5_ctx;
uint8_t md5[16];
uint8_t plain[32];
int i;
if (attr->len != 34) {
log_ppp_warn("radius: %s: incorrect attribute length (%i)\n", attr->attr->name, attr->len);
return -1;
}
if ((attr->val.octets[0] & 0x80) == 0) {
log_ppp_warn("radius: %s: incorrect salt value (%x)\n", attr->attr->name, attr->len);
return -1;
}
MD5_Init(&md5_ctx);
MD5_Update(&md5_ctx, conf_auth_secret, strlen(conf_auth_secret));
MD5_Update(&md5_ctx, req->pack->buf + 4, 16);
MD5_Update(&md5_ctx, attr->val.octets, 2);
MD5_Final(md5, &md5_ctx);
memcpy(plain, attr->val.octets + 2, 32);
for (i = 0; i < 16; i++)
plain[i] ^= md5[i];
if (plain[0] != 16) {
log_ppp_warn("radius: %s: incorrect key length (%i)\n", attr->attr->name, plain[0]);
return -1;
}
MD5_Init(&md5_ctx);
MD5_Update(&md5_ctx, conf_auth_secret, strlen(conf_auth_secret));
MD5_Update(&md5_ctx, attr->val.octets + 2, 16);
MD5_Final(md5, &md5_ctx);
plain[16] ^= md5[0];
memcpy(key, plain + 1, 16);
return 0;
}
static uint8_t* encrypt_password(const char *passwd, const char *secret, const uint8_t *RA, int *epasswd_len)
{
uint8_t *epasswd;
int i, j, chunk_cnt;
uint8_t b[16], c[16];
MD5_CTX ctx;
if (strlen(passwd))
chunk_cnt = (strlen(passwd) - 1) / 16 + 1;
else {
*epasswd_len = 0;
return (uint8_t *)1;
}
epasswd = _malloc(chunk_cnt * 16);
if (!epasswd) {
log_emerg("radius: out of memory\n");
return NULL;
}
memset(epasswd, 0, chunk_cnt * 16);
memcpy(epasswd, passwd, strlen(passwd));
memcpy(c, RA, 16);
for (i = 0; i < chunk_cnt; i++) {
MD5_Init(&ctx);
MD5_Update(&ctx, secret, strlen(secret));
MD5_Update(&ctx, c, 16);
MD5_Final(b, &ctx);
for(j = 0; j < 16; j++)
epasswd[i * 16 + j] ^= b[j];
memcpy(c, epasswd + i * 16, 16);
}
*epasswd_len = chunk_cnt * 16;
return epasswd;
}
static int rad_auth_send(struct rad_req_t *req)
{
int i;
for(i = 0; i < conf_max_try; i++) {
__sync_add_and_fetch(&stat_auth_sent, 1);
if (rad_req_send(req, conf_verbose))
goto out;
rad_req_wait(req, conf_timeout);
if (req->reply) {
if (req->reply->id != req->pack->id) {
__sync_add_and_fetch(&stat_auth_lost, 1);
rad_packet_free(req->reply);
req->reply = NULL;
} else
break;
} else
__sync_add_and_fetch(&stat_auth_lost, 1);
}
if (!req->reply)
log_ppp_warn("radius:auth: no response\n");
else if (req->reply->code == CODE_ACCESS_ACCEPT) {
if (rad_proc_attrs(req))
return PWDB_DENIED;
return PWDB_SUCCESS;
}
out:
return PWDB_DENIED;
}
int rad_auth_pap(struct radius_pd_t *rpd, const char *username, va_list args)
{
struct rad_req_t *req;
int r = PWDB_DENIED;
//int id = va_arg(args, int);
const char *passwd = va_arg(args, const char *);
uint8_t *epasswd;
int epasswd_len;
req = rad_req_alloc(rpd, CODE_ACCESS_REQUEST, username);
if (!req)
return PWDB_DENIED;
epasswd = encrypt_password(passwd, conf_auth_secret, req->RA, &epasswd_len);
if (!epasswd)
goto out;
if (rad_packet_add_octets(req->pack, NULL, "User-Password", epasswd, epasswd_len)) {
if (epasswd_len)
_free(epasswd);
goto out;
}
if (epasswd_len)
_free(epasswd);
if (conf_sid_in_auth)
if (rad_packet_add_str(req->pack, NULL, "Acct-Session-Id", rpd->ppp->sessionid))
return -1;
r = rad_auth_send(req);
if (r == PWDB_SUCCESS) {
struct ev_radius_t ev = {
.ppp = rpd->ppp,
.request = req->pack,
.reply = req->reply,
};
triton_event_fire(EV_RADIUS_ACCESS_ACCEPT, &ev);
}
out:
rad_req_free(req);
return r;
}
int rad_auth_chap_md5(struct radius_pd_t *rpd, const char *username, va_list args)
{
int r = PWDB_DENIED;
uint8_t chap_password[17];
int id = va_arg(args, int);
uint8_t *challenge = va_arg(args, uint8_t *);
int challenge_len = va_arg(args, int);
uint8_t *response = va_arg(args, uint8_t *);
chap_password[0] = id;
memcpy(chap_password + 1, response, 16);
if (!rpd->auth_req) {
rpd->auth_req = rad_req_alloc(rpd, CODE_ACCESS_REQUEST, username);
if (!rpd->auth_req)
return PWDB_DENIED;
if (challenge_len == 16)
memcpy(rpd->auth_req->RA, challenge, 16);
else {
if (rad_packet_add_octets(rpd->auth_req->pack, NULL, "CHAP-Challenge", challenge, challenge_len))
goto out;
}
if (rad_packet_add_octets(rpd->auth_req->pack, NULL, "CHAP-Password", chap_password, 17))
goto out;
} else {
if (challenge_len == 16)
memcpy(rpd->auth_req->RA, challenge, 16);
else {
if (rad_packet_change_octets(rpd->auth_req->pack, NULL, "CHAP-Challenge", challenge, challenge_len))
goto out;
}
if (rad_packet_change_octets(rpd->auth_req->pack, NULL, "CHAP-Password", chap_password, 17))
goto out;
if (rpd->attr_state) {
if (rad_packet_find_attr(rpd->auth_req->pack, NULL, "State")) {
if (rad_packet_change_octets(rpd->auth_req->pack, NULL, "State", rpd->attr_state, rpd->attr_state_len))
goto out;
} else {
if (rad_packet_add_octets(rpd->auth_req->pack, NULL, "State", rpd->attr_state, rpd->attr_state_len))
goto out;
}
}
if (rad_packet_build(rpd->auth_req->pack, rpd->auth_req->RA))
return -1;
}
if (conf_sid_in_auth)
if (rad_packet_add_str(rpd->auth_req->pack, NULL, "Acct-Session-Id", rpd->ppp->sessionid))
goto out;
r = rad_auth_send(rpd->auth_req);
if (r == PWDB_SUCCESS) {
struct ev_radius_t ev = {
.ppp = rpd->ppp,
.request = rpd->auth_req->pack,
.reply = rpd->auth_req->reply,
};
triton_event_fire(EV_RADIUS_ACCESS_ACCEPT, &ev);
rpd->auth_req->pack->id++;
}
return r;
out:
rad_req_free(rpd->auth_req);
rpd->auth_req = NULL;
return r;
}
static void setup_mppe(struct rad_req_t *req, const uint8_t *challenge)
{
struct rad_attr_t *attr;
uint8_t mppe_recv_key[16];
uint8_t mppe_send_key[16];
struct ev_mppe_keys_t ev_mppe = {
.ppp = req->rpd->ppp,
};
list_for_each_entry(attr, &req->reply->attrs, entry) {
if (attr->vendor && attr->vendor->id == Vendor_Microsoft) {
switch (attr->attr->id) {
case MS_CHAP_MPPE_Keys:
if (decrypt_chap_mppe_keys(req, attr, challenge, mppe_recv_key))
continue;
ev_mppe.recv_key = mppe_recv_key;
ev_mppe.send_key = mppe_recv_key;
break;
case MS_MPPE_Recv_Key:
if (decrypt_mppe_key(req, attr, mppe_recv_key))
continue;
ev_mppe.recv_key = mppe_recv_key;
break;
case MS_MPPE_Send_Key:
if (decrypt_mppe_key(req, attr, mppe_send_key))
continue;
ev_mppe.send_key = mppe_send_key;
break;
case MS_MPPE_Encryption_Policy:
ev_mppe.policy = attr->val.integer;
break;
case MS_MPPE_Encryption_Type:
ev_mppe.type = attr->val.integer;
break;
}
}
}
if (ev_mppe.recv_key && ev_mppe.send_key)
triton_event_fire(EV_MPPE_KEYS, &ev_mppe);
}
int rad_auth_mschap_v1(struct radius_pd_t *rpd, const char *username, va_list args)
{
int r = PWDB_DENIED;
uint8_t response[50];
int id = va_arg(args, int);
const uint8_t *challenge = va_arg(args, const uint8_t *);
int challenge_len = va_arg(args, int);
const uint8_t *lm_response = va_arg(args, const uint8_t *);
const uint8_t *nt_response = va_arg(args, const uint8_t *);
int flags = va_arg(args, int);
response[0] = id;
response[1] = flags;
memcpy(response + 2, lm_response, 24);
memcpy(response + 2 + 24, nt_response, 24);
if (!rpd->auth_req) {
rpd->auth_req = rad_req_alloc(rpd, CODE_ACCESS_REQUEST, username);
if (!rpd->auth_req)
return PWDB_DENIED;
if (rad_packet_add_octets(rpd->auth_req->pack, "Microsoft", "MS-CHAP-Challenge", challenge, challenge_len))
goto out;
if (rad_packet_add_octets(rpd->auth_req->pack, "Microsoft", "MS-CHAP-Response", response, sizeof(response)))
goto out;
} else {
if (rad_packet_change_octets(rpd->auth_req->pack, "Microsoft", "MS-CHAP-Challenge", challenge, challenge_len))
goto out;
if (rad_packet_change_octets(rpd->auth_req->pack, "Microsoft", "MS-CHAP-Response", response, sizeof(response)))
goto out;
if (rpd->attr_state) {
if (rad_packet_find_attr(rpd->auth_req->pack, NULL, "State")) {
if (rad_packet_change_octets(rpd->auth_req->pack, NULL, "State", rpd->attr_state, rpd->attr_state_len))
goto out;
} else {
if (rad_packet_add_octets(rpd->auth_req->pack, NULL, "State", rpd->attr_state, rpd->attr_state_len))
goto out;
}
}
if (rad_packet_build(rpd->auth_req->pack, rpd->auth_req->RA))
return -1;
}
if (conf_sid_in_auth)
if (rad_packet_add_str(rpd->auth_req->pack, NULL, "Acct-Session-Id", rpd->ppp->sessionid))
goto out;
r = rad_auth_send(rpd->auth_req);
if (r == PWDB_SUCCESS) {
struct ev_radius_t ev = {
.ppp = rpd->ppp,
.request = rpd->auth_req->pack,
.reply = rpd->auth_req->reply,
};
triton_event_fire(EV_RADIUS_ACCESS_ACCEPT, &ev);
setup_mppe(rpd->auth_req, challenge);
rpd->auth_req->pack->id++;
}
return r;
out:
rad_req_free(rpd->auth_req);
rpd->auth_req = NULL;
return r;
}
int rad_auth_mschap_v2(struct radius_pd_t *rpd, const char *username, va_list args)
{
int r = PWDB_DENIED;
struct rad_attr_t *ra;
uint8_t mschap_response[50];
int id = va_arg(args, int);
const uint8_t *challenge = va_arg(args, const uint8_t *);
const uint8_t *peer_challenge = va_arg(args, const uint8_t *);
const uint8_t *reserved = va_arg(args, const uint8_t *);
const uint8_t *response = va_arg(args, const uint8_t *);
int flags = va_arg(args, int);
uint8_t *authenticator = va_arg(args, uint8_t *);
mschap_response[0] = id;
mschap_response[1] = flags;
memcpy(mschap_response + 2, peer_challenge, 16);
memcpy(mschap_response + 2 + 16, reserved, 8);
memcpy(mschap_response + 2 + 16 + 8, response, 24);
if (!rpd->auth_req) {
rpd->auth_req = rad_req_alloc(rpd, CODE_ACCESS_REQUEST, username);
if (!rpd->auth_req)
return PWDB_DENIED;
if (rad_packet_add_octets(rpd->auth_req->pack, "Microsoft", "MS-CHAP-Challenge", challenge, 16))
goto out;
if (rad_packet_add_octets(rpd->auth_req->pack, "Microsoft", "MS-CHAP2-Response", mschap_response, sizeof(mschap_response)))
goto out;
} else {
if (rad_packet_change_octets(rpd->auth_req->pack, "Microsoft", "MS-CHAP-Challenge", challenge, 16))
goto out;
if (rad_packet_change_octets(rpd->auth_req->pack, "Microsoft", "MS-CHAP2-Response", mschap_response, sizeof(mschap_response)))
goto out;
if (rpd->attr_state) {
if (rad_packet_find_attr(rpd->auth_req->pack, NULL, "State")) {
if (rad_packet_change_octets(rpd->auth_req->pack, NULL, "State", rpd->attr_state, rpd->attr_state_len))
goto out;
} else {
if (rad_packet_add_octets(rpd->auth_req->pack, NULL, "State", rpd->attr_state, rpd->attr_state_len))
goto out;
}
}
if (rad_packet_build(rpd->auth_req->pack, rpd->auth_req->RA))
return -1;
}
if (conf_sid_in_auth)
if (rad_packet_add_str(rpd->auth_req->pack, NULL, "Acct-Session-Id", rpd->ppp->sessionid))
goto out;
r = rad_auth_send(rpd->auth_req);
if (r == PWDB_SUCCESS) {
ra = rad_packet_find_attr(rpd->auth_req->reply, "Microsoft", "MS-CHAP2-Success");
if (!ra) {
log_error("radius:auth:mschap-v2: 'MS-CHAP-Success' not found in radius response\n");
r = PWDB_DENIED;
} else
memcpy(authenticator, ra->val.octets + 3, 40);
}
if (r == PWDB_SUCCESS) {
struct ev_radius_t ev = {
.ppp = rpd->ppp,
.request = rpd->auth_req->pack,
.reply = rpd->auth_req->reply,
};
triton_event_fire(EV_RADIUS_ACCESS_ACCEPT, &ev);
setup_mppe(rpd->auth_req, NULL);
rpd->auth_req->pack->id++;
}
return r;
out:
rad_req_free(rpd->auth_req);
rpd->auth_req = NULL;
return r;
}
|