-/* See the file COPYING for licensing information. */
+/* Copyright 2010-2013 NORDUnet A/S. All rights reserved.
+ See LICENSE for licensing information. */
#if defined HAVE_CONFIG_H
#include <config.h>
#endif
+#include <stdlib.h>
+#include <unistd.h>
#include <assert.h>
+#include <fcntl.h>
+#include <limits.h>
#include <openssl/ssl.h>
+#include <openssl/err.h>
+#include <openssl/bn.h>
+#include <openssl/x509v3.h>
+#include <openssl/rand.h>
#include <radsec/radsec.h>
#include <radsec/radsec-impl.h>
#include <regex.h>
-#include "rsp_list.h"
-#include "../radsecproxy.h"
+#include "radsecproxy/list.h"
+#include "radsecproxy/radsecproxy.h"
+
+#include "tls.h"
static struct tls *
_get_tlsconf (struct rs_connection *conn, const struct rs_realm *realm)
return c;
}
+#if defined RS_ENABLE_TLS_PSK
+static unsigned int
+psk_client_cb (SSL *ssl,
+ const char *hint,
+ char *identity,
+ unsigned int max_identity_len,
+ unsigned char *psk,
+ unsigned int max_psk_len)
+{
+ struct rs_connection *conn = NULL;
+ struct rs_credentials *cred = NULL;
+
+ conn = SSL_get_ex_data (ssl, 0);
+ assert (conn != NULL);
+ cred = conn->active_peer->realm->transport_cred;
+ assert (cred != NULL);
+ /* NOTE: Ignoring identity hint from server. */
+
+ if (strlen (cred->identity) + 1 > max_identity_len)
+ {
+ rs_err_conn_push (conn, RSE_CRED, "PSK identity longer than max %d",
+ max_identity_len - 1);
+ return 0;
+ }
+ strcpy (identity, cred->identity);
+
+ switch (cred->secret_encoding)
+ {
+ case RS_KEY_ENCODING_UTF8:
+ cred->secret_len = strlen (cred->secret);
+ if (cred->secret_len > max_psk_len)
+ {
+ rs_err_conn_push (conn, RSE_CRED, "PSK secret longer than max %d",
+ max_psk_len);
+ return 0;
+ }
+ memcpy (psk, cred->secret, cred->secret_len);
+ break;
+ case RS_KEY_ENCODING_ASCII_HEX:
+ {
+ BIGNUM *bn = NULL;
+
+ if (BN_hex2bn (&bn, cred->secret) == 0)
+ {
+ rs_err_conn_push (conn, RSE_CRED, "Unable to convert pskhexstr");
+ if (bn != NULL)
+ BN_clear_free (bn);
+ return 0;
+ }
+ if ((unsigned int) BN_num_bytes (bn) > max_psk_len)
+ {
+ rs_err_conn_push (conn, RSE_CRED, "PSK secret longer than max %d",
+ max_psk_len);
+ BN_clear_free (bn);
+ return 0;
+ }
+ cred->secret_len = BN_bn2bin (bn, psk);
+ BN_clear_free (bn);
+ }
+ break;
+ default:
+ assert (!"unknown psk encoding");
+ }
+
+ return cred->secret_len;
+}
+#endif /* RS_ENABLE_TLS_PSK */
+
+/** Read \a buf_len bytes from one of the random devices into \a
+ buf. Return 0 on success and -1 on failure. */
+static int
+load_rand_ (uint8_t *buf, size_t buf_len)
+{
+ static const char *fns[] = {"/dev/urandom", "/dev/random", NULL};
+ int i;
+
+ if (buf_len > SSIZE_MAX)
+ return -1;
+
+ for (i = 0; fns[i] != NULL; i++)
+ {
+ size_t nread = 0;
+ int fd = open (fns[i], O_RDONLY);
+ if (fd < 0)
+ continue;
+ while (nread != buf_len)
+ {
+ ssize_t r = read (fd, buf + nread, buf_len - nread);
+ if (r < 0)
+ return -1;
+ if (r == 0)
+ break;
+ nread += r;
+ }
+ close (fd);
+ if (nread != buf_len)
+ return -1;
+ return 0;
+ }
+ return -1;
+}
+
+/** Initialise OpenSSL's PRNG by possibly invoking RAND_poll() and by
+ feeding RAND_seed() data from one of the random devices. If either
+ succeeds, we're happy and return 0. */
+static int
+init_openssl_rand_ (void)
+{
+ long openssl_version = 0;
+ int openssl_random_init_flag = 0;
+ int our_random_init_flag = 0;
+ uint8_t buf[32];
+
+ /* Older OpenSSL has a crash bug in RAND_poll (when a file it opens
+ gets a file descriptor with a number higher than FD_SETSIZE) so
+ use it only for newer versions. */
+ openssl_version = SSLeay ();
+ if (openssl_version >= OPENSSL_V (0,9,8,'c'))
+ openssl_random_init_flag = RAND_poll ();
+
+ our_random_init_flag = !load_rand_ (buf, sizeof(buf));
+ if (our_random_init_flag)
+ RAND_seed (buf, sizeof(buf));
+ memset (buf, 0, sizeof(buf)); /* FIXME: What if memset() is optimised out? */
+
+ if (!openssl_random_init_flag && !our_random_init_flag)
+ return -1;
+ if (!RAND_bytes (buf, sizeof(buf)))
+ return -1;
+ return 0;
+}
+
+/** Initialise the TLS library. Return 0 on success, -1 on failure. */
int
-rs_tls_init (struct rs_connection *conn)
+tls_init (void)
{
- struct rs_context *ctx;
- struct tls *tlsconf;
- SSL_CTX *ssl_ctx;
- SSL *ssl;
+ SSL_load_error_strings ();
+ SSL_library_init ();
+ return init_openssl_rand_ ();
+}
+
+int
+tls_init_conn (struct rs_connection *conn)
+{
+ struct rs_context *ctx = NULL;
+ struct tls *tlsconf = NULL;
+ SSL_CTX *ssl_ctx = NULL;
+ SSL *ssl = NULL;
+ unsigned long sslerr = 0;
+
assert (conn->ctx);
ctx = conn->ctx;
tlsconf = _get_tlsconf (conn, conn->active_peer->realm);
if (!tlsconf)
return -1;
- ssl_ctx = tlsgetctx (RADPROT_TLS, tlsconf);
+ ssl_ctx = tlsgetctx (RAD_TLS, tlsconf);
if (!ssl_ctx)
{
- /* TODO: check radsecproxy error */
- return rs_err_conn_push_fl (conn, RSE_SOME_ERROR, __FILE__, __LINE__,
- NULL);
+ for (sslerr = ERR_get_error (); sslerr; sslerr = ERR_get_error ())
+ rs_err_conn_push_fl (conn, RSE_SSLERR, __FILE__, __LINE__,
+ ERR_error_string (sslerr, NULL));
+ return -1;
}
-
ssl = SSL_new (ssl_ctx);
if (!ssl)
{
- /* TODO: check and report SSL error */
- /* TODO: free ssl_ctx */
- return rs_err_conn_push_fl (conn, RSE_SOME_ERROR, __FILE__, __LINE__,
- NULL);
+ for (sslerr = ERR_get_error (); sslerr; sslerr = ERR_get_error ())
+ rs_err_conn_push_fl (conn, RSE_SSLERR, __FILE__, __LINE__,
+ ERR_error_string (sslerr, NULL));
+ return -1;
}
+#if defined RS_ENABLE_TLS_PSK
+ if (conn->active_peer->realm->transport_cred != NULL)
+ {
+ SSL_set_psk_client_callback (ssl, psk_client_cb);
+ SSL_set_ex_data (ssl, 0, conn);
+ }
+#endif /* RS_ENABLE_TLS_PSK */
+
conn->tls_ctx = ssl_ctx;
conn->tls_ssl = ssl;
rs_free (ctx, tlsconf);
return RSE_OK;
}
+
+/* draft-ietf-radext-radsec-11.txt
+
+ * Certificate validation MUST include the verification rules as
+ per [RFC5280].
+
+ * Implementations SHOULD indicate their acceptable Certification
+ Authorities as per section 7.4.4 (server side) and x.y.z
+ ["Trusted CA Indication"] (client side) of [RFC5246] (see
+ Section 3.2)
+
+ * Implementations SHOULD allow to configure a list of acceptable
+ certificates, identified via certificate fingerprint. When a
+ fingerprint configured, the fingerprint is prepended with an
+ ASCII label identifying the hash function followed by a colon.
+ Implementations MUST support SHA-1 as the hash algorithm and
+ use the ASCII label "sha-1" to identify the SHA-1 algorithm.
+ The length of a SHA-1 hash is 20 bytes and the length of the
+ corresponding fingerprint string is 65 characters. An example
+ certificate fingerprint is: sha-
+ 1:E1:2D:53:2B:7C:6B:8A:29:A2:76:C8:64:36:0B:08:4B:7A:F1:9E:9D
+
+ * Peer validation always includes a check on whether the locally
+ configured expected DNS name or IP address of the server that
+ is contacted matches its presented certificate. DNS names and
+ IP addresses can be contained in the Common Name (CN) or
+ subjectAltName entries. For verification, only one of these
+ entries is to be considered. The following precedence
+ applies: for DNS name validation, subjectAltName:DNS has
+ precedence over CN; for IP address validation, subjectAltName:
+ iPAddr has precedence over CN.
+
+ * Implementations SHOULD allow to configure a set of acceptable
+ values for subjectAltName:URI.
+ */
+int
+tls_verify_cert (struct rs_connection *conn)
+{
+ int err = 0;
+ int success = 0;
+ X509 *peer_cert = NULL;
+ struct in6_addr addr;
+ const char *hostname = NULL;
+
+ assert (conn->active_peer->conn == conn);
+ assert (conn->active_peer->hostname != NULL);
+ hostname = conn->active_peer->hostname;
+
+ /* verifytlscert() performs basic verification as described by
+ OpenSSL VERIFY(1), i.e. verification of the certificate chain. */
+ peer_cert = verifytlscert (conn->tls_ssl);
+ if (peer_cert == NULL)
+ {
+ err = rs_err_conn_push (conn, RSE_SSLERR,
+ "basic certificate validation failed");
+ goto out;
+ }
+
+ if (inet_pton (AF_INET, hostname, &addr))
+ success = (subjectaltnameaddr (peer_cert, AF_INET, &addr) == 1);
+ else if (inet_pton (AF_INET6, hostname, &addr))
+ success = (subjectaltnameaddr (peer_cert, AF_INET6, &addr) == 1);
+ else
+ success = (subjectaltnameregexp (peer_cert, GEN_DNS, hostname, NULL) == 1);
+
+ if (!success)
+ success = (cnregexp (peer_cert, hostname, NULL) == 1);
+
+ if (conn->realm->disable_hostname_check)
+ success = 1;
+ if (!success)
+ err = rs_err_conn_push (conn, RSE_CERT, "server certificate doesn't "
+ "match configured hostname \"%s\"", hostname);
+
+ out:
+ if (peer_cert != NULL)
+ X509_free (peer_cert);
+ return err;
+}