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authorAlberto Gonzalez Iniesta <agi@inittab.org>2014-04-16 17:32:08 +0200
committerAlberto Gonzalez Iniesta <agi@inittab.org>2014-04-16 17:32:08 +0200
commit0af7f64094c65cba7ee45bd2679e6826bcf598cb (patch)
tree43702d27f33b48a461e3f84d1931b89aa3070d4f /src/openvpn/ssl_openssl.c
parent70b71e008cc968ee53d6b8af9f7a006f13c27e2a (diff)
Imported Upstream version 2.3.3upstream/2.3.3
Diffstat (limited to 'src/openvpn/ssl_openssl.c')
-rw-r--r--src/openvpn/ssl_openssl.c143
1 files changed, 121 insertions, 22 deletions
diff --git a/src/openvpn/ssl_openssl.c b/src/openvpn/ssl_openssl.c
index 79cc056..5689e7c 100644
--- a/src/openvpn/ssl_openssl.c
+++ b/src/openvpn/ssl_openssl.c
@@ -103,8 +103,17 @@ tmp_rsa_cb (SSL * s, int is_export, int keylength)
static RSA *rsa_tmp = NULL;
if (rsa_tmp == NULL)
{
+ int ret = -1;
+ BIGNUM *bn = BN_new();
+ rsa_tmp = RSA_new();
+
msg (D_HANDSHAKE, "Generating temp (%d bit) RSA key", keylength);
- rsa_tmp = RSA_generate_key (keylength, RSA_F4, NULL, NULL);
+
+ if(!bn || !BN_set_word(bn, RSA_F4) ||
+ !RSA_generate_key_ex(rsa_tmp, keylength, bn, NULL))
+ msg(M_SSLERR, "Failed to generate temp RSA key");
+
+ if (bn) BN_free( bn );
}
return (rsa_tmp);
}
@@ -114,10 +123,10 @@ tls_ctx_server_new(struct tls_root_ctx *ctx)
{
ASSERT(NULL != ctx);
- ctx->ctx = SSL_CTX_new (TLSv1_server_method ());
+ ctx->ctx = SSL_CTX_new (SSLv23_server_method ());
if (ctx->ctx == NULL)
- msg (M_SSLERR, "SSL_CTX_new TLSv1_server_method");
+ msg (M_SSLERR, "SSL_CTX_new SSLv23_server_method");
SSL_CTX_set_tmp_rsa_callback (ctx->ctx, tmp_rsa_cb);
}
@@ -127,10 +136,10 @@ tls_ctx_client_new(struct tls_root_ctx *ctx)
{
ASSERT(NULL != ctx);
- ctx->ctx = SSL_CTX_new (TLSv1_client_method ());
+ ctx->ctx = SSL_CTX_new (SSLv23_client_method ());
if (ctx->ctx == NULL)
- msg (M_SSLERR, "SSL_CTX_new TLSv1_client_method");
+ msg (M_SSLERR, "SSL_CTX_new SSLv23_client_method");
}
void
@@ -174,13 +183,46 @@ info_callback (INFO_CALLBACK_SSL_CONST SSL * s, int where, int ret)
}
}
+/*
+ * Return maximum TLS version supported by local OpenSSL library.
+ * Assume that presence of SSL_OP_NO_TLSvX macro indicates that
+ * TLSvX is supported.
+ */
+int
+tls_version_max(void)
+{
+#if defined(SSL_OP_NO_TLSv1_2)
+ return TLS_VER_1_2;
+#elif defined(SSL_OP_NO_TLSv1_1)
+ return TLS_VER_1_1;
+#else
+ return TLS_VER_1_0;
+#endif
+}
+
void
tls_ctx_set_options (struct tls_root_ctx *ctx, unsigned int ssl_flags)
{
ASSERT(NULL != ctx);
+ /* process SSL options including minimum TLS version we will accept from peer */
+ {
+ long sslopt = SSL_OP_SINGLE_DH_USE | SSL_OP_NO_TICKET | SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3;
+ const int tls_version_min = (ssl_flags >> SSLF_TLS_VERSION_SHIFT) & SSLF_TLS_VERSION_MASK;
+ if (tls_version_min > TLS_VER_1_0)
+ sslopt |= SSL_OP_NO_TLSv1;
+#ifdef SSL_OP_NO_TLSv1_1
+ if (tls_version_min > TLS_VER_1_1)
+ sslopt |= SSL_OP_NO_TLSv1_1;
+#endif
+#ifdef SSL_OP_NO_TLSv1_2
+ if (tls_version_min > TLS_VER_1_2)
+ sslopt |= SSL_OP_NO_TLSv1_2;
+#endif
+ SSL_CTX_set_options (ctx->ctx, sslopt);
+ }
+
SSL_CTX_set_session_cache_mode (ctx->ctx, SSL_SESS_CACHE_OFF);
- SSL_CTX_set_options (ctx->ctx, SSL_OP_SINGLE_DH_USE);
SSL_CTX_set_default_passwd_cb (ctx->ctx, pem_password_callback);
/* Require peer certificate verification */
@@ -380,16 +422,34 @@ tls_ctx_load_pkcs12(struct tls_root_ctx *ctx, const char *pkcs12_file,
/* Set Certificate Verification chain */
if (load_ca_file)
{
+ /* Add CAs from PKCS12 to the cert store and mark them as trusted.
+ * They're also used to fill in the chain of intermediate certs as
+ * necessary.
+ */
if (ca && sk_X509_num(ca))
{
for (i = 0; i < sk_X509_num(ca); i++)
{
- if (!X509_STORE_add_cert(ctx->ctx->cert_store,sk_X509_value(ca, i)))
+ if (!X509_STORE_add_cert(ctx->ctx->cert_store,sk_X509_value(ca, i)))
msg (M_SSLERR, "Cannot add certificate to certificate chain (X509_STORE_add_cert)");
if (!SSL_CTX_add_client_CA(ctx->ctx, sk_X509_value(ca, i)))
msg (M_SSLERR, "Cannot add certificate to client CA list (SSL_CTX_add_client_CA)");
}
}
+ } else {
+ /* If trusted CA certs were loaded from a PEM file, and we ignore the
+ * ones in PKCS12, do load PKCS12-provided certs to the client extra
+ * certs chain just in case they include intermediate CAs needed to
+ * prove my identity to the other end. This does not make them trusted.
+ */
+ if (ca && sk_X509_num(ca))
+ {
+ for (i = 0; i < sk_X509_num(ca); i++)
+ {
+ if (!SSL_CTX_add_extra_chain_cert(ctx->ctx,sk_X509_value(ca, i)))
+ msg (M_SSLERR, "Cannot add extra certificate to chain (SSL_CTX_add_extra_chain_cert)");
+ }
+ }
}
return 0;
}
@@ -423,9 +483,10 @@ tls_ctx_add_extra_certs (struct tls_root_ctx *ctx, BIO *bio)
}
}
-void
-tls_ctx_load_cert_file (struct tls_root_ctx *ctx, const char *cert_file,
- const char *cert_file_inline, X509 **x509
+/* Like tls_ctx_load_cert, but returns a copy of the certificate in **X509 */
+static void
+tls_ctx_load_cert_file_and_copy (struct tls_root_ctx *ctx,
+ const char *cert_file, const char *cert_file_inline, X509 **x509
)
{
BIO *in = NULL;
@@ -480,6 +541,13 @@ end:
}
void
+tls_ctx_load_cert_file (struct tls_root_ctx *ctx, const char *cert_file,
+ const char *cert_file_inline)
+{
+ tls_ctx_load_cert_file_and_copy (ctx, cert_file, cert_file_inline, NULL);
+}
+
+void
tls_ctx_free_cert_file (X509 *x509)
{
X509_free(x509);
@@ -616,15 +684,19 @@ rsa_priv_enc(int flen, const unsigned char *from, unsigned char *to, RSA *rsa, i
}
int
-tls_ctx_use_external_private_key (struct tls_root_ctx *ctx, X509 *cert)
+tls_ctx_use_external_private_key (struct tls_root_ctx *ctx,
+ const char *cert_file, const char *cert_file_inline)
{
RSA *rsa = NULL;
RSA *pub_rsa;
RSA_METHOD *rsa_meth;
+ X509 *cert = NULL;
ASSERT (NULL != ctx);
ASSERT (NULL != cert);
+ tls_ctx_load_cert_file_and_copy (ctx, cert_file, cert_file_inline, &cert);
+
/* allocate custom RSA method object */
ALLOC_OBJ_CLEAR (rsa_meth, RSA_METHOD);
rsa_meth->name = "OpenVPN external private key RSA Method";
@@ -659,10 +731,13 @@ tls_ctx_use_external_private_key (struct tls_root_ctx *ctx, X509 *cert)
if (!SSL_CTX_use_RSAPrivateKey(ctx->ctx, rsa))
goto err;
+ X509_free(cert);
RSA_free(rsa); /* doesn't necessarily free, just decrements refcount */
return 1;
err:
+ if (cert)
+ X509_free(cert);
if (rsa)
RSA_free(rsa);
else
@@ -694,7 +769,7 @@ tls_ctx_load_ca (struct tls_root_ctx *ctx, const char *ca_file,
X509_STORE *store = NULL;
X509_NAME *xn = NULL;
BIO *in = NULL;
- int i, added = 0;
+ int i, added = 0, prev = 0;
ASSERT(NULL != ctx);
@@ -721,6 +796,11 @@ tls_ctx_load_ca (struct tls_root_ctx *ctx, const char *ca_file,
if (info->crl)
X509_STORE_add_crl (store, info->crl);
+ if (tls_server && !info->x509)
+ {
+ msg (M_SSLERR, "X509 name was missing in TLS mode");
+ }
+
if (info->x509)
{
X509_STORE_add_cert (store, info->x509);
@@ -750,6 +830,15 @@ tls_ctx_load_ca (struct tls_root_ctx *ctx, const char *ca_file,
sk_X509_NAME_push (cert_names, xn);
}
}
+
+ if (tls_server) {
+ int cnum = sk_X509_NAME_num (cert_names);
+ if (cnum != (prev + 1)) {
+ msg (M_WARN, "Cannot load CA certificate file %s (entry %d did not validate)", np(ca_file), added);
+ }
+ prev = cnum;
+ }
+
}
sk_X509_INFO_pop_free (info_stack, X509_INFO_free);
}
@@ -757,8 +846,15 @@ tls_ctx_load_ca (struct tls_root_ctx *ctx, const char *ca_file,
if (tls_server)
SSL_CTX_set_client_CA_list (ctx->ctx, cert_names);
- if (!added || (tls_server && sk_X509_NAME_num (cert_names) != added))
- msg (M_SSLERR, "Cannot load CA certificate file %s", np(ca_file));
+ if (!added)
+ msg (M_SSLERR, "Cannot load CA certificate file %s (no entries were read)", np(ca_file));
+
+ if (tls_server) {
+ int cnum = sk_X509_NAME_num (cert_names);
+ if (cnum != added)
+ msg (M_SSLERR, "Cannot load CA certificate file %s (only %d of %d entries were valid X509 names)", np(ca_file), cnum, added);
+ }
+
if (in)
BIO_free (in);
}
@@ -1015,7 +1111,7 @@ bio_read (BIO *bio, struct buffer *buf, int maxlen, const char *desc)
}
void
-key_state_ssl_init(struct key_state_ssl *ks_ssl, const struct tls_root_ctx *ssl_ctx, bool is_server, void *session)
+key_state_ssl_init(struct key_state_ssl *ks_ssl, const struct tls_root_ctx *ssl_ctx, bool is_server, struct tls_session *session)
{
ASSERT(NULL != ssl_ctx);
ASSERT(ks_ssl);
@@ -1188,23 +1284,26 @@ print_details (struct key_state_ssl * ks_ssl, const char *prefix)
}
void
-show_available_tls_ciphers ()
+show_available_tls_ciphers (const char *cipher_list)
{
- SSL_CTX *ctx;
+ struct tls_root_ctx tls_ctx;
SSL *ssl;
const char *cipher_name;
const char *print_name;
const tls_cipher_name_pair *pair;
int priority = 0;
- ctx = SSL_CTX_new (TLSv1_method ());
- if (!ctx)
+ tls_ctx.ctx = SSL_CTX_new (SSLv23_method ());
+ if (!tls_ctx.ctx)
msg (M_SSLERR, "Cannot create SSL_CTX object");
- ssl = SSL_new (ctx);
+ ssl = SSL_new (tls_ctx.ctx);
if (!ssl)
msg (M_SSLERR, "Cannot create SSL object");
+ if (cipher_list)
+ tls_ctx_restrict_ciphers(&tls_ctx, cipher_list);
+
printf ("Available TLS Ciphers,\n");
printf ("listed in order of preference:\n\n");
while ((cipher_name = SSL_get_cipher_list (ssl, priority++)))
@@ -1222,7 +1321,7 @@ show_available_tls_ciphers ()
printf ("\n");
SSL_free (ssl);
- SSL_CTX_free (ctx);
+ SSL_CTX_free (tls_ctx.ctx);
}
void
@@ -1232,7 +1331,7 @@ get_highest_preference_tls_cipher (char *buf, int size)
SSL *ssl;
const char *cipher_name;
- ctx = SSL_CTX_new (TLSv1_method ());
+ ctx = SSL_CTX_new (SSLv23_method ());
if (!ctx)
msg (M_SSLERR, "Cannot create SSL_CTX object");
ssl = SSL_new (ctx);