NetBSD-5.0.2/dist/wpa/src/eap_server/eap_sim_db.c
/*
* hostapd / EAP-SIM database/authenticator gateway
* Copyright (c) 2005-2007, 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.
*
* This is an example implementation of the EAP-SIM/AKA database/authentication
* gateway interface that is using an external program as an SS7 gateway to
* GSM/UMTS authentication center (HLR/AuC). hlr_auc_gw is an example
* implementation of such a gateway program. This eap_sim_db.c takes care of
* EAP-SIM/AKA pseudonyms and re-auth identities. It can be used with different
* gateway implementations for HLR/AuC access. Alternatively, it can also be
* completely replaced if the in-memory database of pseudonyms/re-auth
* identities is not suitable for some cases.
*/
#include "includes.h"
#include <sys/un.h>
#include "common.h"
#include "eap_common/eap_sim_common.h"
#include "eap_server/eap_sim_db.h"
#include "eloop.h"
struct eap_sim_pseudonym {
struct eap_sim_pseudonym *next;
u8 *identity;
size_t identity_len;
char *pseudonym;
};
struct eap_sim_db_pending {
struct eap_sim_db_pending *next;
u8 imsi[20];
size_t imsi_len;
enum { PENDING, SUCCESS, FAILURE } state;
void *cb_session_ctx;
struct os_time timestamp;
int aka;
union {
struct {
u8 kc[EAP_SIM_MAX_CHAL][EAP_SIM_KC_LEN];
u8 sres[EAP_SIM_MAX_CHAL][EAP_SIM_SRES_LEN];
u8 rand[EAP_SIM_MAX_CHAL][GSM_RAND_LEN];
int num_chal;
} sim;
struct {
u8 rand[EAP_AKA_RAND_LEN];
u8 autn[EAP_AKA_AUTN_LEN];
u8 ik[EAP_AKA_IK_LEN];
u8 ck[EAP_AKA_CK_LEN];
u8 res[EAP_AKA_RES_MAX_LEN];
size_t res_len;
} aka;
} u;
};
struct eap_sim_db_data {
int sock;
char *fname;
char *local_sock;
void (*get_complete_cb)(void *ctx, void *session_ctx);
void *ctx;
struct eap_sim_pseudonym *pseudonyms;
struct eap_sim_reauth *reauths;
struct eap_sim_db_pending *pending;
};
static struct eap_sim_db_pending *
eap_sim_db_get_pending(struct eap_sim_db_data *data, const u8 *imsi,
size_t imsi_len, int aka)
{
struct eap_sim_db_pending *entry, *prev = NULL;
entry = data->pending;
while (entry) {
if (entry->aka == aka && entry->imsi_len == imsi_len &&
os_memcmp(entry->imsi, imsi, imsi_len) == 0) {
if (prev)
prev->next = entry->next;
else
data->pending = entry->next;
break;
}
prev = entry;
entry = entry->next;
}
return entry;
}
static void eap_sim_db_add_pending(struct eap_sim_db_data *data,
struct eap_sim_db_pending *entry)
{
entry->next = data->pending;
data->pending = entry;
}
static void eap_sim_db_sim_resp_auth(struct eap_sim_db_data *data,
const char *imsi, char *buf)
{
char *start, *end, *pos;
struct eap_sim_db_pending *entry;
int num_chal;
/*
* SIM-RESP-AUTH <IMSI> Kc(i):SRES(i):RAND(i) ...
* SIM-RESP-AUTH <IMSI> FAILURE
* (IMSI = ASCII string, Kc/SRES/RAND = hex string)
*/
entry = eap_sim_db_get_pending(data, (u8 *) imsi, os_strlen(imsi), 0);
if (entry == NULL) {
wpa_printf(MSG_DEBUG, "EAP-SIM DB: No pending entry for the "
"received message found");
return;
}
start = buf;
if (os_strncmp(start, "FAILURE", 7) == 0) {
wpa_printf(MSG_DEBUG, "EAP-SIM DB: External server reported "
"failure");
entry->state = FAILURE;
eap_sim_db_add_pending(data, entry);
data->get_complete_cb(data->ctx, entry->cb_session_ctx);
return;
}
num_chal = 0;
while (num_chal < EAP_SIM_MAX_CHAL) {
end = os_strchr(start, ' ');
if (end)
*end = '\0';
pos = os_strchr(start, ':');
if (pos == NULL)
goto parse_fail;
*pos = '\0';
if (hexstr2bin(start, entry->u.sim.kc[num_chal],
EAP_SIM_KC_LEN))
goto parse_fail;
start = pos + 1;
pos = os_strchr(start, ':');
if (pos == NULL)
goto parse_fail;
*pos = '\0';
if (hexstr2bin(start, entry->u.sim.sres[num_chal],
EAP_SIM_SRES_LEN))
goto parse_fail;
start = pos + 1;
if (hexstr2bin(start, entry->u.sim.rand[num_chal],
GSM_RAND_LEN))
goto parse_fail;
num_chal++;
if (end == NULL)
break;
else
start = end + 1;
}
entry->u.sim.num_chal = num_chal;
entry->state = SUCCESS;
wpa_printf(MSG_DEBUG, "EAP-SIM DB: Authentication data parsed "
"successfully - callback");
eap_sim_db_add_pending(data, entry);
data->get_complete_cb(data->ctx, entry->cb_session_ctx);
return;
parse_fail:
wpa_printf(MSG_DEBUG, "EAP-SIM DB: Failed to parse response string");
os_free(entry);
}
static void eap_sim_db_aka_resp_auth(struct eap_sim_db_data *data,
const char *imsi, char *buf)
{
char *start, *end;
struct eap_sim_db_pending *entry;
/*
* AKA-RESP-AUTH <IMSI> <RAND> <AUTN> <IK> <CK> <RES>
* AKA-RESP-AUTH <IMSI> FAILURE
* (IMSI = ASCII string, RAND/AUTN/IK/CK/RES = hex string)
*/
entry = eap_sim_db_get_pending(data, (u8 *) imsi, os_strlen(imsi), 1);
if (entry == NULL) {
wpa_printf(MSG_DEBUG, "EAP-SIM DB: No pending entry for the "
"received message found");
return;
}
start = buf;
if (os_strncmp(start, "FAILURE", 7) == 0) {
wpa_printf(MSG_DEBUG, "EAP-SIM DB: External server reported "
"failure");
entry->state = FAILURE;
eap_sim_db_add_pending(data, entry);
data->get_complete_cb(data->ctx, entry->cb_session_ctx);
return;
}
end = os_strchr(start, ' ');
if (end == NULL)
goto parse_fail;
*end = '\0';
if (hexstr2bin(start, entry->u.aka.rand, EAP_AKA_RAND_LEN))
goto parse_fail;
start = end + 1;
end = os_strchr(start, ' ');
if (end == NULL)
goto parse_fail;
*end = '\0';
if (hexstr2bin(start, entry->u.aka.autn, EAP_AKA_AUTN_LEN))
goto parse_fail;
start = end + 1;
end = os_strchr(start, ' ');
if (end == NULL)
goto parse_fail;
*end = '\0';
if (hexstr2bin(start, entry->u.aka.ik, EAP_AKA_IK_LEN))
goto parse_fail;
start = end + 1;
end = os_strchr(start, ' ');
if (end == NULL)
goto parse_fail;
*end = '\0';
if (hexstr2bin(start, entry->u.aka.ck, EAP_AKA_CK_LEN))
goto parse_fail;
start = end + 1;
end = os_strchr(start, ' ');
if (end)
*end = '\0';
else {
end = start;
while (*end)
end++;
}
entry->u.aka.res_len = (end - start) / 2;
if (entry->u.aka.res_len > EAP_AKA_RES_MAX_LEN) {
wpa_printf(MSG_DEBUG, "EAP-SIM DB: Too long RES");
entry->u.aka.res_len = 0;
goto parse_fail;
}
if (hexstr2bin(start, entry->u.aka.res, entry->u.aka.res_len))
goto parse_fail;
entry->state = SUCCESS;
wpa_printf(MSG_DEBUG, "EAP-SIM DB: Authentication data parsed "
"successfully - callback");
eap_sim_db_add_pending(data, entry);
data->get_complete_cb(data->ctx, entry->cb_session_ctx);
return;
parse_fail:
wpa_printf(MSG_DEBUG, "EAP-SIM DB: Failed to parse response string");
os_free(entry);
}
static void eap_sim_db_receive(int sock, void *eloop_ctx, void *sock_ctx)
{
struct eap_sim_db_data *data = eloop_ctx;
char buf[1000], *pos, *cmd, *imsi;
int res;
res = recv(sock, buf, sizeof(buf), 0);
if (res < 0)
return;
wpa_hexdump_ascii_key(MSG_MSGDUMP, "EAP-SIM DB: Received from an "
"external source", (u8 *) buf, res);
if (res == 0)
return;
if (res >= (int) sizeof(buf))
res = sizeof(buf) - 1;
buf[res] = '\0';
if (data->get_complete_cb == NULL) {
wpa_printf(MSG_DEBUG, "EAP-SIM DB: No get_complete_cb "
"registered");
return;
}
/* <cmd> <IMSI> ... */
cmd = buf;
pos = os_strchr(cmd, ' ');
if (pos == NULL)
goto parse_fail;
*pos = '\0';
imsi = pos + 1;
pos = os_strchr(imsi, ' ');
if (pos == NULL)
goto parse_fail;
*pos = '\0';
wpa_printf(MSG_DEBUG, "EAP-SIM DB: External response=%s for IMSI %s",
cmd, imsi);
if (os_strcmp(cmd, "SIM-RESP-AUTH") == 0)
eap_sim_db_sim_resp_auth(data, imsi, pos + 1);
else if (os_strcmp(cmd, "AKA-RESP-AUTH") == 0)
eap_sim_db_aka_resp_auth(data, imsi, pos + 1);
else
wpa_printf(MSG_INFO, "EAP-SIM DB: Unknown external response "
"'%s'", cmd);
return;
parse_fail:
wpa_printf(MSG_DEBUG, "EAP-SIM DB: Failed to parse response string");
}
static int eap_sim_db_open_socket(struct eap_sim_db_data *data)
{
struct sockaddr_un addr;
static int counter = 0;
if (os_strncmp(data->fname, "unix:", 5) != 0)
return -1;
data->sock = socket(PF_UNIX, SOCK_DGRAM, 0);
if (data->sock < 0) {
perror("socket(eap_sim_db)");
return -1;
}
os_memset(&addr, 0, sizeof(addr));
addr.sun_family = AF_UNIX;
os_snprintf(addr.sun_path, sizeof(addr.sun_path),
"/tmp/eap_sim_db_%d-%d", getpid(), counter++);
data->local_sock = os_strdup(addr.sun_path);
if (bind(data->sock, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
perror("bind(eap_sim_db)");
close(data->sock);
data->sock = -1;
return -1;
}
os_memset(&addr, 0, sizeof(addr));
addr.sun_family = AF_UNIX;
os_strlcpy(addr.sun_path, data->fname + 5, sizeof(addr.sun_path));
if (connect(data->sock, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
perror("connect(eap_sim_db)");
wpa_hexdump_ascii(MSG_INFO, "HLR/AuC GW socket",
(u8 *) addr.sun_path,
os_strlen(addr.sun_path));
close(data->sock);
data->sock = -1;
return -1;
}
eloop_register_read_sock(data->sock, eap_sim_db_receive, data, NULL);
return 0;
}
static void eap_sim_db_close_socket(struct eap_sim_db_data *data)
{
if (data->sock >= 0) {
eloop_unregister_read_sock(data->sock);
close(data->sock);
data->sock = -1;
}
if (data->local_sock) {
unlink(data->local_sock);
os_free(data->local_sock);
data->local_sock = NULL;
}
}
/**
* eap_sim_db_init - Initialize EAP-SIM DB / authentication gateway interface
* @config: Configuration data (e.g., file name)
* @get_complete_cb: Callback function for reporting availability of triplets
* @ctx: Context pointer for get_complete_cb
* Returns: Pointer to a private data structure or %NULL on failure
*/
void * eap_sim_db_init(const char *config,
void (*get_complete_cb)(void *ctx, void *session_ctx),
void *ctx)
{
struct eap_sim_db_data *data;
data = os_zalloc(sizeof(*data));
if (data == NULL)
return NULL;
data->sock = -1;
data->get_complete_cb = get_complete_cb;
data->ctx = ctx;
data->fname = os_strdup(config);
if (data->fname == NULL)
goto fail;
if (os_strncmp(data->fname, "unix:", 5) == 0) {
if (eap_sim_db_open_socket(data))
goto fail;
}
return data;
fail:
eap_sim_db_close_socket(data);
os_free(data->fname);
os_free(data);
return NULL;
}
static void eap_sim_db_free_pseudonym(struct eap_sim_pseudonym *p)
{
os_free(p->identity);
os_free(p->pseudonym);
os_free(p);
}
static void eap_sim_db_free_reauth(struct eap_sim_reauth *r)
{
os_free(r->identity);
os_free(r->reauth_id);
os_free(r);
}
/**
* eap_sim_db_deinit - Deinitialize EAP-SIM DB/authentication gw interface
* @priv: Private data pointer from eap_sim_db_init()
*/
void eap_sim_db_deinit(void *priv)
{
struct eap_sim_db_data *data = priv;
struct eap_sim_pseudonym *p, *prev;
struct eap_sim_reauth *r, *prevr;
struct eap_sim_db_pending *pending, *prev_pending;
eap_sim_db_close_socket(data);
os_free(data->fname);
p = data->pseudonyms;
while (p) {
prev = p;
p = p->next;
eap_sim_db_free_pseudonym(prev);
}
r = data->reauths;
while (r) {
prevr = r;
r = r->next;
eap_sim_db_free_reauth(prevr);
}
pending = data->pending;
while (pending) {
prev_pending = pending;
pending = pending->next;
os_free(prev_pending);
}
os_free(data);
}
static int eap_sim_db_send(struct eap_sim_db_data *data, const char *msg,
size_t len)
{
int _errno = 0;
if (send(data->sock, msg, len, 0) < 0) {
_errno = errno;
perror("send[EAP-SIM DB UNIX]");
}
if (_errno == ENOTCONN || _errno == EDESTADDRREQ || _errno == EINVAL ||
_errno == ECONNREFUSED) {
/* Try to reconnect */
eap_sim_db_close_socket(data);
if (eap_sim_db_open_socket(data) < 0)
return -1;
wpa_printf(MSG_DEBUG, "EAP-SIM DB: Reconnected to the "
"external server");
if (send(data->sock, msg, len, 0) < 0) {
perror("send[EAP-SIM DB UNIX]");
return -1;
}
}
return 0;
}
static void eap_sim_db_expire_pending(struct eap_sim_db_data *data)
{
/* TODO: add limit for maximum length for pending list; remove latest
* (i.e., last) entry from the list if the limit is reached; could also
* use timeout to expire pending entries */
}
/**
* eap_sim_db_get_gsm_triplets - Get GSM triplets
* @priv: Private data pointer from eap_sim_db_init()
* @identity: User name identity
* @identity_len: Length of identity in bytes
* @max_chal: Maximum number of triplets
* @_rand: Buffer for RAND values
* @kc: Buffer for Kc values
* @sres: Buffer for SRES values
* @cb_session_ctx: Session callback context for get_complete_cb()
* Returns: Number of triplets received (has to be less than or equal to
* max_chal), -1 (EAP_SIM_DB_FAILURE) on error (e.g., user not found), or
* -2 (EAP_SIM_DB_PENDING) if results are not yet available. In this case, the
* callback function registered with eap_sim_db_init() will be called once the
* results become available.
*
* In most cases, the user name is '1' | IMSI, i.e., 1 followed by the IMSI in
* ASCII format.
*
* When using an external server for GSM triplets, this function can always
* start a request and return EAP_SIM_DB_PENDING immediately if authentication
* triplets are not available. Once the triplets are received, callback
* function registered with eap_sim_db_init() is called to notify EAP state
* machine to reprocess the message. This eap_sim_db_get_gsm_triplets()
* function will then be called again and the newly received triplets will then
* be given to the caller.
*/
int eap_sim_db_get_gsm_triplets(void *priv, const u8 *identity,
size_t identity_len, int max_chal,
u8 *_rand, u8 *kc, u8 *sres,
void *cb_session_ctx)
{
struct eap_sim_db_data *data = priv;
struct eap_sim_db_pending *entry;
int len, ret;
size_t i;
char msg[40];
if (identity_len < 2 || identity[0] != EAP_SIM_PERMANENT_PREFIX) {
wpa_hexdump_ascii(MSG_DEBUG, "EAP-SIM DB: unexpected identity",
identity, identity_len);
return EAP_SIM_DB_FAILURE;
}
identity++;
identity_len--;
for (i = 0; i < identity_len; i++) {
if (identity[i] == '@') {
identity_len = i;
break;
}
}
if (identity_len + 1 > sizeof(entry->imsi)) {
wpa_hexdump_ascii(MSG_DEBUG, "EAP-SIM DB: unexpected identity",
identity, identity_len);
return EAP_SIM_DB_FAILURE;
}
wpa_hexdump_ascii(MSG_DEBUG, "EAP-SIM DB: Get GSM triplets for IMSI",
identity, identity_len);
entry = eap_sim_db_get_pending(data, identity, identity_len, 0);
if (entry) {
int num_chal;
if (entry->state == FAILURE) {
wpa_printf(MSG_DEBUG, "EAP-SIM DB: Pending entry -> "
"failure");
os_free(entry);
return EAP_SIM_DB_FAILURE;
}
if (entry->state == PENDING) {
wpa_printf(MSG_DEBUG, "EAP-SIM DB: Pending entry -> "
"still pending");
eap_sim_db_add_pending(data, entry);
return EAP_SIM_DB_PENDING;
}
wpa_printf(MSG_DEBUG, "EAP-SIM DB: Pending entry -> "
"%d challenges", entry->u.sim.num_chal);
num_chal = entry->u.sim.num_chal;
if (num_chal > max_chal)
num_chal = max_chal;
os_memcpy(_rand, entry->u.sim.rand, num_chal * GSM_RAND_LEN);
os_memcpy(sres, entry->u.sim.sres,
num_chal * EAP_SIM_SRES_LEN);
os_memcpy(kc, entry->u.sim.kc, num_chal * EAP_SIM_KC_LEN);
os_free(entry);
return num_chal;
}
if (data->sock < 0) {
if (eap_sim_db_open_socket(data) < 0)
return EAP_SIM_DB_FAILURE;
}
len = os_snprintf(msg, sizeof(msg), "SIM-REQ-AUTH ");
if (len < 0 || len + identity_len >= sizeof(msg))
return EAP_SIM_DB_FAILURE;
os_memcpy(msg + len, identity, identity_len);
len += identity_len;
ret = os_snprintf(msg + len, sizeof(msg) - len, " %d", max_chal);
if (ret < 0 || (size_t) ret >= sizeof(msg) - len)
return EAP_SIM_DB_FAILURE;
len += ret;
wpa_hexdump(MSG_DEBUG, "EAP-SIM DB: requesting SIM authentication "
"data for IMSI", identity, identity_len);
if (eap_sim_db_send(data, msg, len) < 0)
return EAP_SIM_DB_FAILURE;
entry = os_zalloc(sizeof(*entry));
if (entry == NULL)
return EAP_SIM_DB_FAILURE;
os_get_time(&entry->timestamp);
os_memcpy(entry->imsi, identity, identity_len);
entry->imsi_len = identity_len;
entry->cb_session_ctx = cb_session_ctx;
entry->state = PENDING;
eap_sim_db_add_pending(data, entry);
eap_sim_db_expire_pending(data);
return EAP_SIM_DB_PENDING;
}
static struct eap_sim_pseudonym *
eap_sim_db_get_pseudonym(struct eap_sim_db_data *data, const u8 *identity,
size_t identity_len)
{
char *pseudonym;
size_t len;
struct eap_sim_pseudonym *p;
if (identity_len == 0 ||
(identity[0] != EAP_SIM_PSEUDONYM_PREFIX &&
identity[0] != EAP_AKA_PSEUDONYM_PREFIX))
return NULL;
/* Remove possible realm from identity */
len = 0;
while (len < identity_len) {
if (identity[len] == '@')
break;
len++;
}
pseudonym = os_malloc(len + 1);
if (pseudonym == NULL)
return NULL;
os_memcpy(pseudonym, identity, len);
pseudonym[len] = '\0';
p = data->pseudonyms;
while (p) {
if (os_strcmp(p->pseudonym, pseudonym) == 0)
break;
p = p->next;
}
os_free(pseudonym);
return p;
}
static struct eap_sim_pseudonym *
eap_sim_db_get_pseudonym_id(struct eap_sim_db_data *data, const u8 *identity,
size_t identity_len)
{
struct eap_sim_pseudonym *p;
if (identity_len == 0 ||
(identity[0] != EAP_SIM_PERMANENT_PREFIX &&
identity[0] != EAP_AKA_PERMANENT_PREFIX))
return NULL;
p = data->pseudonyms;
while (p) {
if (identity_len == p->identity_len &&
os_memcmp(p->identity, identity, identity_len) == 0)
break;
p = p->next;
}
return p;
}
static struct eap_sim_reauth *
eap_sim_db_get_reauth(struct eap_sim_db_data *data, const u8 *identity,
size_t identity_len)
{
char *reauth_id;
size_t len;
struct eap_sim_reauth *r;
if (identity_len == 0 ||
(identity[0] != EAP_SIM_REAUTH_ID_PREFIX &&
identity[0] != EAP_AKA_REAUTH_ID_PREFIX))
return NULL;
/* Remove possible realm from identity */
len = 0;
while (len < identity_len) {
if (identity[len] == '@')
break;
len++;
}
reauth_id = os_malloc(len + 1);
if (reauth_id == NULL)
return NULL;
os_memcpy(reauth_id, identity, len);
reauth_id[len] = '\0';
r = data->reauths;
while (r) {
if (os_strcmp(r->reauth_id, reauth_id) == 0)
break;
r = r->next;
}
os_free(reauth_id);
return r;
}
static struct eap_sim_reauth *
eap_sim_db_get_reauth_id(struct eap_sim_db_data *data, const u8 *identity,
size_t identity_len)
{
struct eap_sim_pseudonym *p;
struct eap_sim_reauth *r;
if (identity_len == 0)
return NULL;
p = eap_sim_db_get_pseudonym(data, identity, identity_len);
if (p == NULL)
p = eap_sim_db_get_pseudonym_id(data, identity, identity_len);
if (p) {
identity = p->identity;
identity_len = p->identity_len;
}
r = data->reauths;
while (r) {
if (identity_len == r->identity_len &&
os_memcmp(r->identity, identity, identity_len) == 0)
break;
r = r->next;
}
return r;
}
/**
* eap_sim_db_identity_known - Verify whether the given identity is known
* @priv: Private data pointer from eap_sim_db_init()
* @identity: User name identity
* @identity_len: Length of identity in bytes
* Returns: 0 if the user is found or -1 on failure
*
* In most cases, the user name is ['0','1'] | IMSI, i.e., 1 followed by the
* IMSI in ASCII format, ['2','3'] | pseudonym, or ['4','5'] | reauth_id.
*/
int eap_sim_db_identity_known(void *priv, const u8 *identity,
size_t identity_len)
{
struct eap_sim_db_data *data = priv;
if (identity == NULL || identity_len < 2)
return -1;
if (identity[0] == EAP_SIM_PSEUDONYM_PREFIX ||
identity[0] == EAP_AKA_PSEUDONYM_PREFIX) {
struct eap_sim_pseudonym *p =
eap_sim_db_get_pseudonym(data, identity, identity_len);
return p ? 0 : -1;
}
if (identity[0] == EAP_SIM_REAUTH_ID_PREFIX ||
identity[0] == EAP_AKA_REAUTH_ID_PREFIX) {
struct eap_sim_reauth *r =
eap_sim_db_get_reauth(data, identity, identity_len);
return r ? 0 : -1;
}
if (identity[0] != EAP_SIM_PERMANENT_PREFIX &&
identity[0] != EAP_AKA_PERMANENT_PREFIX) {
/* Unknown identity prefix */
return -1;
}
/* TODO: Should consider asking HLR/AuC gateway whether this permanent
* identity is known. If it is, EAP-SIM/AKA can skip identity request.
* In case of EAP-AKA, this would reduce number of needed round-trips.
* Ideally, this would be done with one wait, i.e., just request
* authentication data and store it for the next use. This would then
* need to use similar pending-request functionality as the normal
* request for authentication data at later phase.
*/
return -1;
}
static char * eap_sim_db_get_next(struct eap_sim_db_data *data, char prefix)
{
char *id, *pos, *end;
u8 buf[10];
if (os_get_random(buf, sizeof(buf)))
return NULL;
id = os_malloc(sizeof(buf) * 2 + 2);
if (id == NULL)
return NULL;
pos = id;
end = id + sizeof(buf) * 2 + 2;
*pos++ = prefix;
pos += wpa_snprintf_hex(pos, end - pos, buf, sizeof(buf));
return id;
}
/**
* eap_sim_db_get_next_pseudonym - EAP-SIM DB: Get next pseudonym
* @priv: Private data pointer from eap_sim_db_init()
* @aka: Using EAP-AKA instead of EAP-SIM
* Returns: Next pseudonym (allocated string) or %NULL on failure
*
* This function is used to generate a pseudonym for EAP-SIM. The returned
* pseudonym is not added to database at this point; it will need to be added
* with eap_sim_db_add_pseudonym() once the authentication has been completed
* successfully. Caller is responsible for freeing the returned buffer.
*/
char * eap_sim_db_get_next_pseudonym(void *priv, int aka)
{
struct eap_sim_db_data *data = priv;
return eap_sim_db_get_next(data, aka ? EAP_AKA_PSEUDONYM_PREFIX :
EAP_SIM_PSEUDONYM_PREFIX);
}
/**
* eap_sim_db_get_next_reauth_id - EAP-SIM DB: Get next reauth_id
* @priv: Private data pointer from eap_sim_db_init()
* @aka: Using EAP-AKA instead of EAP-SIM
* Returns: Next reauth_id (allocated string) or %NULL on failure
*
* This function is used to generate a fast re-authentication identity for
* EAP-SIM. The returned reauth_id is not added to database at this point; it
* will need to be added with eap_sim_db_add_reauth() once the authentication
* has been completed successfully. Caller is responsible for freeing the
* returned buffer.
*/
char * eap_sim_db_get_next_reauth_id(void *priv, int aka)
{
struct eap_sim_db_data *data = priv;
return eap_sim_db_get_next(data, aka ? EAP_AKA_REAUTH_ID_PREFIX :
EAP_SIM_REAUTH_ID_PREFIX);
}
/**
* eap_sim_db_add_pseudonym - EAP-SIM DB: Add new pseudonym
* @priv: Private data pointer from eap_sim_db_init()
* @identity: Identity of the user (may be permanent identity or pseudonym)
* @identity_len: Length of identity
* @pseudonym: Pseudonym for this user. This needs to be an allocated buffer,
* e.g., return value from eap_sim_db_get_next_pseudonym(). Caller must not
* free it.
* Returns: 0 on success, -1 on failure
*
* This function adds a new pseudonym for EAP-SIM user. EAP-SIM DB is
* responsible of freeing pseudonym buffer once it is not needed anymore.
*/
int eap_sim_db_add_pseudonym(void *priv, const u8 *identity,
size_t identity_len, char *pseudonym)
{
struct eap_sim_db_data *data = priv;
struct eap_sim_pseudonym *p;
wpa_hexdump_ascii(MSG_DEBUG, "EAP-SIM DB: Add pseudonym for identity",
identity, identity_len);
wpa_printf(MSG_DEBUG, "EAP-SIM DB: Pseudonym: %s", pseudonym);
/* TODO: could store last two pseudonyms */
p = eap_sim_db_get_pseudonym(data, identity, identity_len);
if (p == NULL)
p = eap_sim_db_get_pseudonym_id(data, identity, identity_len);
if (p) {
wpa_printf(MSG_DEBUG, "EAP-SIM DB: Replacing previous "
"pseudonym: %s", p->pseudonym);
os_free(p->pseudonym);
p->pseudonym = pseudonym;
return 0;
}
p = os_zalloc(sizeof(*p));
if (p == NULL) {
os_free(pseudonym);
return -1;
}
p->next = data->pseudonyms;
p->identity = os_malloc(identity_len);
if (p->identity == NULL) {
os_free(p);
os_free(pseudonym);
return -1;
}
os_memcpy(p->identity, identity, identity_len);
p->identity_len = identity_len;
p->pseudonym = pseudonym;
data->pseudonyms = p;
wpa_printf(MSG_DEBUG, "EAP-SIM DB: Added new pseudonym entry");
return 0;
}
/**
* eap_sim_db_add_reauth - EAP-SIM DB: Add new re-authentication entry
* @priv: Private data pointer from eap_sim_db_init()
* @identity: Identity of the user (may be permanent identity or pseudonym)
* @identity_len: Length of identity
* @reauth_id: reauth_id for this user. This needs to be an allocated buffer,
* e.g., return value from eap_sim_db_get_next_reauth_id(). Caller must not
* free it.
* @mk: 16-byte MK from the previous full authentication
* Returns: 0 on success, -1 on failure
*
* This function adds a new re-authentication entry for an EAP-SIM user.
* EAP-SIM DB is responsible of freeing reauth_id buffer once it is not needed
* anymore.
*/
int eap_sim_db_add_reauth(void *priv, const u8 *identity,
size_t identity_len, char *reauth_id, u16 counter,
const u8 *mk)
{
struct eap_sim_db_data *data = priv;
struct eap_sim_reauth *r;
wpa_hexdump_ascii(MSG_DEBUG, "EAP-SIM DB: Add reauth_id for identity",
identity, identity_len);
wpa_printf(MSG_DEBUG, "EAP-SIM DB: reauth_id: %s", reauth_id);
r = eap_sim_db_get_reauth(data, identity, identity_len);
if (r == NULL)
r = eap_sim_db_get_reauth_id(data, identity, identity_len);
if (r) {
wpa_printf(MSG_DEBUG, "EAP-SIM DB: Replacing previous "
"reauth_id: %s", r->reauth_id);
os_free(r->reauth_id);
r->reauth_id = reauth_id;
} else {
r = os_zalloc(sizeof(*r));
if (r == NULL) {
os_free(reauth_id);
return -1;
}
r->next = data->reauths;
r->identity = os_malloc(identity_len);
if (r->identity == NULL) {
os_free(r);
os_free(reauth_id);
return -1;
}
os_memcpy(r->identity, identity, identity_len);
r->identity_len = identity_len;
r->reauth_id = reauth_id;
data->reauths = r;
wpa_printf(MSG_DEBUG, "EAP-SIM DB: Added new reauth entry");
}
r->counter = counter;
os_memcpy(r->mk, mk, EAP_SIM_MK_LEN);
return 0;
}
/**
* eap_sim_db_get_permanent - EAP-SIM DB: Get permanent identity
* @priv: Private data pointer from eap_sim_db_init()
* @identity: Identity of the user (may be permanent identity or pseudonym)
* @identity_len: Length of identity
* @len: Buffer for length of the returned permanent identity
* Returns: Pointer to the permanent identity, or %NULL if not found
*/
const u8 * eap_sim_db_get_permanent(void *priv, const u8 *identity,
size_t identity_len, size_t *len)
{
struct eap_sim_db_data *data = priv;
struct eap_sim_pseudonym *p;
if (identity == NULL)
return NULL;
p = eap_sim_db_get_pseudonym(data, identity, identity_len);
if (p == NULL)
p = eap_sim_db_get_pseudonym_id(data, identity, identity_len);
if (p == NULL)
return NULL;
*len = p->identity_len;
return p->identity;
}
/**
* eap_sim_db_get_reauth_entry - EAP-SIM DB: Get re-authentication entry
* @priv: Private data pointer from eap_sim_db_init()
* @identity: Identity of the user (may be permanent identity, pseudonym, or
* reauth_id)
* @identity_len: Length of identity
* @len: Buffer for length of the returned permanent identity
* Returns: Pointer to the re-auth entry, or %NULL if not found
*/
struct eap_sim_reauth *
eap_sim_db_get_reauth_entry(void *priv, const u8 *identity,
size_t identity_len)
{
struct eap_sim_db_data *data = priv;
struct eap_sim_reauth *r;
if (identity == NULL)
return NULL;
r = eap_sim_db_get_reauth(data, identity, identity_len);
if (r == NULL)
r = eap_sim_db_get_reauth_id(data, identity, identity_len);
return r;
}
/**
* eap_sim_db_remove_reauth - EAP-SIM DB: Remove re-authentication entry
* @priv: Private data pointer from eap_sim_db_init()
* @reauth: Pointer to re-authentication entry from
* eap_sim_db_get_reauth_entry()
*/
void eap_sim_db_remove_reauth(void *priv, struct eap_sim_reauth *reauth)
{
struct eap_sim_db_data *data = priv;
struct eap_sim_reauth *r, *prev = NULL;
r = data->reauths;
while (r) {
if (r == reauth) {
if (prev)
prev->next = r->next;
else
data->reauths = r->next;
eap_sim_db_free_reauth(r);
return;
}
prev = r;
r = r->next;
}
}
/**
* eap_sim_db_get_aka_auth - Get AKA authentication values
* @priv: Private data pointer from eap_sim_db_init()
* @identity: User name identity
* @identity_len: Length of identity in bytes
* @_rand: Buffer for RAND value
* @autn: Buffer for AUTN value
* @ik: Buffer for IK value
* @ck: Buffer for CK value
* @res: Buffer for RES value
* @res_len: Buffer for RES length
* @cb_session_ctx: Session callback context for get_complete_cb()
* Returns: 0 on success, -1 (EAP_SIM_DB_FAILURE) on error (e.g., user not
* found), or -2 (EAP_SIM_DB_PENDING) if results are not yet available. In this
* case, the callback function registered with eap_sim_db_init() will be
* called once the results become available.
*
* In most cases, the user name is '0' | IMSI, i.e., 0 followed by the IMSI in
* ASCII format.
*
* When using an external server for AKA authentication, this function can
* always start a request and return EAP_SIM_DB_PENDING immediately if
* authentication triplets are not available. Once the authentication data are
* received, callback function registered with eap_sim_db_init() is called to
* notify EAP state machine to reprocess the message. This
* eap_sim_db_get_aka_auth() function will then be called again and the newly
* received triplets will then be given to the caller.
*/
int eap_sim_db_get_aka_auth(void *priv, const u8 *identity,
size_t identity_len, u8 *_rand, u8 *autn, u8 *ik,
u8 *ck, u8 *res, size_t *res_len,
void *cb_session_ctx)
{
struct eap_sim_db_data *data = priv;
struct eap_sim_db_pending *entry;
int len;
size_t i;
char msg[40];
if (identity_len < 2 || identity == NULL ||
identity[0] != EAP_AKA_PERMANENT_PREFIX) {
wpa_hexdump_ascii(MSG_DEBUG, "EAP-SIM DB: unexpected identity",
identity, identity_len);
return EAP_SIM_DB_FAILURE;
}
identity++;
identity_len--;
for (i = 0; i < identity_len; i++) {
if (identity[i] == '@') {
identity_len = i;
break;
}
}
if (identity_len + 1 > sizeof(entry->imsi)) {
wpa_hexdump_ascii(MSG_DEBUG, "EAP-SIM DB: unexpected identity",
identity, identity_len);
return EAP_SIM_DB_FAILURE;
}
wpa_hexdump_ascii(MSG_DEBUG, "EAP-SIM DB: Get AKA auth for IMSI",
identity, identity_len);
entry = eap_sim_db_get_pending(data, identity, identity_len, 1);
if (entry) {
if (entry->state == FAILURE) {
os_free(entry);
wpa_printf(MSG_DEBUG, "EAP-SIM DB: Failure");
return EAP_SIM_DB_FAILURE;
}
if (entry->state == PENDING) {
eap_sim_db_add_pending(data, entry);
wpa_printf(MSG_DEBUG, "EAP-SIM DB: Pending");
return EAP_SIM_DB_PENDING;
}
wpa_printf(MSG_DEBUG, "EAP-SIM DB: Returning successfully "
"received authentication data");
os_memcpy(_rand, entry->u.aka.rand, EAP_AKA_RAND_LEN);
os_memcpy(autn, entry->u.aka.autn, EAP_AKA_AUTN_LEN);
os_memcpy(ik, entry->u.aka.ik, EAP_AKA_IK_LEN);
os_memcpy(ck, entry->u.aka.ck, EAP_AKA_CK_LEN);
os_memcpy(res, entry->u.aka.res, EAP_AKA_RES_MAX_LEN);
*res_len = entry->u.aka.res_len;
os_free(entry);
return 0;
}
if (data->sock < 0) {
if (eap_sim_db_open_socket(data) < 0)
return EAP_SIM_DB_FAILURE;
}
len = os_snprintf(msg, sizeof(msg), "AKA-REQ-AUTH ");
if (len < 0 || len + identity_len >= sizeof(msg))
return EAP_SIM_DB_FAILURE;
os_memcpy(msg + len, identity, identity_len);
len += identity_len;
wpa_hexdump(MSG_DEBUG, "EAP-SIM DB: requesting AKA authentication "
"data for IMSI", identity, identity_len);
if (eap_sim_db_send(data, msg, len) < 0)
return EAP_SIM_DB_FAILURE;
entry = os_zalloc(sizeof(*entry));
if (entry == NULL)
return EAP_SIM_DB_FAILURE;
os_get_time(&entry->timestamp);
entry->aka = 1;
os_memcpy(entry->imsi, identity, identity_len);
entry->imsi_len = identity_len;
entry->cb_session_ctx = cb_session_ctx;
entry->state = PENDING;
eap_sim_db_add_pending(data, entry);
eap_sim_db_expire_pending(data);
return EAP_SIM_DB_PENDING;
}
/**
* eap_sim_db_resynchronize - Resynchronize AKA AUTN
* @priv: Private data pointer from eap_sim_db_init()
* @identity: User name identity
* @identity_len: Length of identity in bytes
* @auts: AUTS value from the peer
* @_rand: RAND value used in the rejected message
* Returns: 0 on success, -1 on failure
*
* This function is called when the peer reports synchronization failure in the
* AUTN value by sending AUTS. The AUTS and RAND values should be sent to
* HLR/AuC to allow it to resynchronize with the peer. After this,
* eap_sim_db_get_aka_auth() will be called again to to fetch updated
* RAND/AUTN values for the next challenge.
*/
int eap_sim_db_resynchronize(void *priv, const u8 *identity,
size_t identity_len, const u8 *auts,
const u8 *_rand)
{
struct eap_sim_db_data *data = priv;
size_t i;
if (identity_len < 2 || identity == NULL ||
identity[0] != EAP_AKA_PERMANENT_PREFIX) {
wpa_hexdump_ascii(MSG_DEBUG, "EAP-SIM DB: unexpected identity",
identity, identity_len);
return -1;
}
identity++;
identity_len--;
for (i = 0; i < identity_len; i++) {
if (identity[i] == '@') {
identity_len = i;
break;
}
}
if (identity_len > 20) {
wpa_hexdump_ascii(MSG_DEBUG, "EAP-SIM DB: unexpected identity",
identity, identity_len);
return -1;
}
if (data->sock >= 0) {
char msg[100];
int len, ret;
len = os_snprintf(msg, sizeof(msg), "AKA-AUTS ");
if (len < 0 || len + identity_len >= sizeof(msg))
return -1;
os_memcpy(msg + len, identity, identity_len);
len += identity_len;
ret = os_snprintf(msg + len, sizeof(msg) - len, " ");
if (ret < 0 || (size_t) ret >= sizeof(msg) - len)
return -1;
len += ret;
len += wpa_snprintf_hex(msg + len, sizeof(msg) - len,
auts, EAP_AKA_AUTS_LEN);
ret = os_snprintf(msg + len, sizeof(msg) - len, " ");
if (ret < 0 || (size_t) ret >= sizeof(msg) - len)
return -1;
len += ret;
len += wpa_snprintf_hex(msg + len, sizeof(msg) - len,
_rand, EAP_AKA_RAND_LEN);
wpa_hexdump(MSG_DEBUG, "EAP-SIM DB: reporting AKA AUTS for "
"IMSI", identity, identity_len);
if (eap_sim_db_send(data, msg, len) < 0)
return -1;
}
return 0;
}