/*
* check if any crls are about to expire
*/
void
check_crls(void)
{
#ifdef HAVE_THREADS
x509crl_t *crl;
time_t current_time = time(NULL);
lock_crl_list("check_crls");
crl = x509crls;
while (crl != NULL)
{
time_t time_left = crl->nextUpdate - current_time;
u_char buf[ASN1_BUF_LEN];
DBG(DBG_X509,
dntoa(buf, ASN1_BUF_LEN, crl->issuer);
DBG_log("issuer: '%s'",buf);
if (crl->authKeyID.ptr != NULL)
{
datatot(crl->authKeyID.ptr, crl->authKeyID.len, ':'
, buf, ASN1_BUF_LEN);
DBG_log("authkey: %s", buf);
}
DBG_log("%ld seconds left", time_left)
)
if (time_left < 2*crl_check_interval)
add_crl_fetch_request(crl->issuer, crl->distributionPoints);
crl = crl->next;
}
unlock_crl_list("check_crls");
#endif
}
void free_crls(void)
{
lock_crl_list("free_crls");
while (x509crls != NULL)
free_first_crl();
unlock_crl_list("free_crls");
}
/*
* verify if a cert hasn't been revoked by a crl
*/
static bool verify_by_crl(/*const*/ x509cert_t *cert, bool strict,
realtime_t *until)
{
x509crl_t *crl;
char ibuf[ASN1_BUF_LEN], cbuf[ASN1_BUF_LEN];
lock_crl_list("verify_by_crl");
crl = get_x509crl(cert->issuer, cert->authKeySerialNumber,
cert->authKeyID);
dntoa(ibuf, ASN1_BUF_LEN, cert->issuer);
if (crl == NULL) {
unlock_crl_list("verify_by_crl");
libreswan_log("no crl from issuer \"%s\" found (strict=%s)",
ibuf,
strict ? "yes" : "no");
#if defined(LIBCURL) || defined(LDAP_VER)
if (cert->crlDistributionPoints != NULL) {
add_crl_fetch_request(cert->issuer,
cert->crlDistributionPoints);
wake_fetch_thread("verify_by_crl");
}
#endif
if (strict)
return FALSE;
} else {
x509cert_t *issuer_cert;
bool valid;
DBG(DBG_X509,
DBG_log("issuer crl \"%s\" found", ibuf));
#if defined(LIBCURL) || defined(LDAP_VER)
add_distribution_points(cert->crlDistributionPoints,
&crl->distributionPoints);
#endif
lock_authcert_list("verify_by_crl");
issuer_cert = get_authcert(crl->issuer,
crl->authKeySerialNumber,
crl->authKeyID, AUTH_CA);
dntoa(cbuf, ASN1_BUF_LEN, crl->issuer);
valid = check_signature(crl->tbsCertList, crl->signature,
crl->algorithm, issuer_cert);
unlock_authcert_list("verify_by_crl");
if (valid) {
bool revoked_crl, expired_crl;
DBG(DBG_X509,
DBG_log("valid crl signature on \"%s\"", cbuf));
/* with strict crl policy the public key must have the same
* lifetime as the crl
*/
if (strict && realbefore(crl->nextUpdate, *until))
*until = crl->nextUpdate;
/* has the certificate been revoked? */
revoked_crl = x509_check_revocation(crl,
cert->serialNumber);
/* is the crl still valid? */
expired_crl = realbefore(crl->nextUpdate, realnow());
unlock_crl_list("verify_by_crl");
if (expired_crl) {
char tbuf[REALTIMETOA_BUF];
libreswan_log(
"crl update for \"%s\" is overdue since %s",
cbuf,
realtimetoa(crl->nextUpdate, TRUE,
tbuf, sizeof(tbuf)));
#if defined(LIBCURL) || defined(LDAP_VER)
/* try to fetch a crl update */
if (cert->crlDistributionPoints != NULL) {
add_crl_fetch_request(cert->issuer,
cert->crlDistributionPoints);
wake_fetch_thread("verify_by_crl");
}
#endif
} else {
DBG(DBG_X509,
DBG_log("crl is \"%s\" valid", cbuf));
}
if (revoked_crl || (strict && expired_crl)) {
/* remove any cached public keys */
remove_x509_public_key(cert);
return FALSE;
}
} else {
unlock_crl_list("verify_by_crl");
libreswan_log("invalid crl signature on \"%s\"", cbuf);
if (strict)
return FALSE;
}
}
return TRUE;
}
/*
* Insert X.509 CRL into chained list
*/
bool insert_crl(chunk_t blob, chunk_t crl_uri)
{
x509crl_t *crl = alloc_thing(x509crl_t, "x509crl");
*crl = empty_x509crl;
if (parse_x509crl(blob, 0, crl)) {
x509cert_t *issuer_cert;
x509crl_t *oldcrl;
bool valid_sig;
generalName_t *gn;
/* add distribution point */
gn = alloc_thing(generalName_t, "generalName");
gn->kind = GN_URI;
gn->name = crl_uri;
gn->next = crl->distributionPoints;
crl->distributionPoints = gn;
lock_authcert_list("insert_crl");
/* get the issuer cacert */
issuer_cert = get_authcert(crl->issuer,
crl->authKeySerialNumber,
crl->authKeyID, AUTH_CA);
if (issuer_cert == NULL) {
chunk_t *n = &crl->distributionPoints->name;
loglog(RC_LOG_SERIOUS,
"CRL rejected: crl issuer cacert not found for %.*s",
(int)n->len, (char *)n->ptr);
free_crl(crl);
unlock_authcert_list("insert_crl");
return FALSE;
}
DBG(DBG_X509,
DBG_log("crl issuer cacert found"));
/* check the issuer's signature of the crl */
valid_sig = check_signature(crl->tbsCertList, crl->signature,
crl->algorithm, issuer_cert);
unlock_authcert_list("insert_crl");
if (!valid_sig) {
free_crl(crl);
return FALSE;
}
DBG(DBG_X509,
DBG_log("valid crl signature"));
lock_crl_list("insert_crl");
oldcrl = get_x509crl(crl->issuer, crl->authKeySerialNumber,
crl->authKeyID);
if (oldcrl != NULL) {
if (realbefore(oldcrl->thisUpdate, crl->thisUpdate)) {
/* old CRL is older than new CRL: replace */
#if defined(LIBCURL) || defined(LDAP_VER)
/* keep any known CRL distribution points */
add_distribution_points(
oldcrl->distributionPoints,
&crl->distributionPoints);
#endif
/* now delete the old CRL */
free_first_crl();
DBG(DBG_X509,
DBG_log("thisUpdate is newer - existing crl deleted"));
} else {
/* old CRL is not older than new CRL: keep old one */
unlock_crl_list("insert_crls");
DBG(DBG_X509,
DBG_log("thisUpdate is not newer - existing crl not replaced"));
free_crl(crl);
/*
* is the fetched crl valid?
* now + 2 * crl_check_interval < oldcrl->nextUpdate
*/
return realbefore(realtimesum(realnow(), deltatimescale(2, 1, crl_check_interval)), oldcrl->nextUpdate);
}
}
/* insert new CRL */
crl->next = x509crls;
x509crls = crl;
unlock_crl_list("insert_crl");
/*
* is the new crl valid?
* now + 2 * crl_check_interval < crl->nextUpdate
*/
return realbefore(realtimesum(realnow(), deltatimescale(2, 1, crl_check_interval)), crl->nextUpdate);
} else {
loglog(RC_LOG_SERIOUS, " error in X.509 crl %s",
(char *)crl_uri.ptr);
free_crl(crl);
return FALSE;
}
}
