This allows OpenVPN to load non-default providers. This is mainly
useful for loading the legacy provider with --provider legacy default

Patch v4: use spaces to seperate providers, unload providers.

Signed-off-by: Arne Schwabe <a...@rfc2549.org>
---
 doc/man-sections/generic-options.rst | 10 ++++++++++
 src/openvpn/crypto_backend.h         | 14 +++++++++++++
 src/openvpn/crypto_mbedtls.c         | 13 ++++++++++++
 src/openvpn/crypto_mbedtls.h         |  3 +++
 src/openvpn/crypto_openssl.c         | 30 ++++++++++++++++++++++++++++
 src/openvpn/crypto_openssl.h         |  9 +++++++++
 src/openvpn/openvpn.c                | 13 ++++++++++++
 src/openvpn/options.c                |  7 +++++++
 src/openvpn/options.h                |  9 +++++++++
 9 files changed, 108 insertions(+)

diff --git a/doc/man-sections/generic-options.rst 
b/doc/man-sections/generic-options.rst
index e6c1fe455..f5b8a9135 100644
--- a/doc/man-sections/generic-options.rst
+++ b/doc/man-sections/generic-options.rst
@@ -280,6 +280,16 @@ which mode OpenVPN is configured as.
   This option solves the problem by persisting keys across :code:`SIGUSR1`
   resets, so they don't need to be re-read.
 
+--provider providers
+  Load the : separated list of (OpenSSL) providers. This is mainly useful for
+  using an external provider for key management like tpm2-openssl or to load
+  the legacy provider with
+
+  ::
+
+      --provider "legacy:default"
+
+
 --remap-usr1 signal
   Control whether internally or externally generated :code:`SIGUSR1` signals
   are remapped to :code:`SIGHUP` (restart without persisting state) or
diff --git a/src/openvpn/crypto_backend.h b/src/openvpn/crypto_backend.h
index 5aab3e1b7..40984c559 100644
--- a/src/openvpn/crypto_backend.h
+++ b/src/openvpn/crypto_backend.h
@@ -78,6 +78,20 @@ void crypto_clear_error(void);
  */
 void crypto_init_lib_engine(const char *engine_name);
 
+
+/**
+ * Load the given (OpenSSL) providers
+ * @param provider name of providers to load
+ * @return reference to the loaded provider
+ */
+provider_t *crypto_load_provider(const char *provider);
+
+/**
+ * Unloads the given (OpneSSL) provider
+ * @param provider pointer to the provider to unload
+ */
+void crypto_unload_provider(const char* provname, provider_t *provider);
+
 #ifdef DMALLOC
 /*
  * OpenSSL memory debugging.  If dmalloc debugging is enabled, tell
diff --git a/src/openvpn/crypto_mbedtls.c b/src/openvpn/crypto_mbedtls.c
index 08b9e004f..39dbf38a5 100644
--- a/src/openvpn/crypto_mbedtls.c
+++ b/src/openvpn/crypto_mbedtls.c
@@ -69,6 +69,19 @@ crypto_init_lib_engine(const char *engine_name)
         "available");
 }
 
+provider_t *crypto_load_provider(const char *provider)
+{
+    if (provider)
+    {
+        msg(M_WARN, "Note: mbed TLS provider functionality is not available");
+    }
+    return NULL;
+}
+
+void crypto_unload_provider(const char* provname, provider_t *provider)
+{
+}
+
 /*
  *
  * Functions related to the core crypto library
diff --git a/src/openvpn/crypto_mbedtls.h b/src/openvpn/crypto_mbedtls.h
index 019de01d1..758ab1b40 100644
--- a/src/openvpn/crypto_mbedtls.h
+++ b/src/openvpn/crypto_mbedtls.h
@@ -48,6 +48,9 @@ typedef mbedtls_md_context_t md_ctx_t;
 /** Generic HMAC %context. */
 typedef mbedtls_md_context_t hmac_ctx_t;
 
+/* Use a dummy type for the provider */
+typedef void provider_t;
+
 /** Maximum length of an IV */
 #define OPENVPN_MAX_IV_LENGTH   MBEDTLS_MAX_IV_LENGTH
 
diff --git a/src/openvpn/crypto_openssl.c b/src/openvpn/crypto_openssl.c
index cc1d62210..ab38d6e5c 100644
--- a/src/openvpn/crypto_openssl.c
+++ b/src/openvpn/crypto_openssl.c
@@ -54,6 +54,9 @@
 #if (OPENSSL_VERSION_NUMBER >= 0x10100000L) && 
!defined(LIBRESSL_VERSION_NUMBER)
 #include <openssl/kdf.h>
 #endif
+#if OPENSSL_VERSION_NUMBER >= 0x30000000L
+#include <openssl/provider.h>
+#endif
 
 #if defined(_WIN32) && defined(OPENSSL_NO_EC)
 #error Windows build with OPENSSL_NO_EC: disabling EC key is not supported.
@@ -149,6 +152,33 @@ crypto_init_lib_engine(const char *engine_name)
 #endif
 }
 
+provider_t *
+crypto_load_provider(const char *provider)
+{
+#if OPENSSL_VERSION_NUMBER >= 0x30000000L
+    /* Load providers into the default (NULL) library context */
+    OSSL_PROVIDER* prov = OSSL_PROVIDER_load(NULL, provider);
+    if (!prov)
+    {
+        crypto_msg(M_FATAL, "failed to load provider '%s'", provider);
+    }
+    return prov;
+#else  /* OPENSSL_VERSION_NUMBER >= 0x30000000L */
+    msg(M_WARN, "Note: OpenSSL hardware crypto engine functionality is not 
available");
+    return NULL;
+#endif
+}
+
+void crypto_unload_provider(const char* provname, provider_t *provider)
+{
+#if OPENSSL_VERSION_NUMBER >= 0x30000000L
+    if (!OSSL_PROVIDER_unload(provider))
+    {
+        crypto_msg(M_FATAL, "failed to undload provider '%s'", provname);
+    }
+#endif
+}
+
 /*
  *
  * Functions related to the core crypto library
diff --git a/src/openvpn/crypto_openssl.h b/src/openvpn/crypto_openssl.h
index e540a76b9..446f08508 100644
--- a/src/openvpn/crypto_openssl.h
+++ b/src/openvpn/crypto_openssl.h
@@ -33,6 +33,10 @@
 #include <openssl/hmac.h>
 #include <openssl/md5.h>
 #include <openssl/sha.h>
+#if OPENSSL_VERSION_NUMBER >= 0x30000000L
+#include <openssl/provider.h>
+#endif
+
 
 /** Generic cipher key type %context. */
 typedef EVP_CIPHER cipher_kt_t;
@@ -49,12 +53,17 @@ typedef EVP_MD_CTX md_ctx_t;
 /** Generic HMAC %context. */
 #if OPENSSL_VERSION_NUMBER < 0x30000000L
 typedef HMAC_CTX hmac_ctx_t;
+
+/* Use a dummy type for the provider */
+typedef void provider_t;
 #else
 typedef struct {
     OSSL_PARAM params[3];
     uint8_t key[EVP_MAX_KEY_LENGTH];
     EVP_MAC_CTX *ctx;
 } hmac_ctx_t;
+
+typedef OSSL_PROVIDER provider_t;
 #endif
 
 /** Maximum length of an IV */
diff --git a/src/openvpn/openvpn.c b/src/openvpn/openvpn.c
index da06f59c2..095d448b0 100644
--- a/src/openvpn/openvpn.c
+++ b/src/openvpn/openvpn.c
@@ -112,10 +112,23 @@ void init_early(struct context *c)
     /* init verbosity and mute levels */
     init_verb_mute(c, IVM_LEVEL_1);
 
+    /* Initialise OpenVPN provider, this needs to be initialised this
+    * early since option post-processing and also openssl info
+    * printing depends on it */
+    for (int j=1; j < MAX_PARMS && c->options.providers.names[j]; j++)
+    {
+        c->options.providers.providers[j] =
+            crypto_load_provider(c->options.providers.names[j]);
+    }
 }
 
 static void uninit_early(struct context *c)
 {
+    for (int j=1; j < MAX_PARMS && c->options.providers.providers[j]; j++)
+    {
+        crypto_unload_provider(c->options.providers.names[j],
+                               c->options.providers.providers[j]);
+    }
     net_ctx_free(&c->net_ctx);
 }
 
diff --git a/src/openvpn/options.c b/src/openvpn/options.c
index b5d65d293..87062d58d 100644
--- a/src/openvpn/options.c
+++ b/src/openvpn/options.c
@@ -8157,6 +8157,13 @@ add_option(struct options *options,
             options->engine = "auto";
         }
     }
+    else if (streq(p[0], "provider") && p[1])
+    {
+        for (size_t j = 1; j < MAX_PARMS && p[j] != NULL;j++)
+        {
+            options->providers.names[j] = p[j];
+        }
+    }
 #endif /* ENABLE_CRYPTO_MBEDTLS */
 #ifdef ENABLE_PREDICTION_RESISTANCE
     else if (streq(p[0], "use-prediction-resistance") && !p[1])
diff --git a/src/openvpn/options.h b/src/openvpn/options.h
index 20b34ed4e..d4f41cd71 100644
--- a/src/openvpn/options.h
+++ b/src/openvpn/options.h
@@ -179,6 +179,14 @@ struct remote_list
     struct remote_entry *array[CONNECTION_LIST_SIZE];
 };
 
+struct provider_list
+{
+    /* Names of the providers */
+    const char *names[MAX_PARMS];
+    /* Pointers to the loaded providers to unload them */
+    provider_t *providers[MAX_PARMS];
+};
+
 enum vlan_acceptable_frames
 {
     VLAN_ONLY_TAGGED,
@@ -519,6 +527,7 @@ struct options
     const char *ncp_ciphers;
     const char *authname;
     const char *engine;
+    struct provider_list providers;
     bool replay;
     bool mute_replay_warnings;
     int replay_window;
-- 
2.33.0



_______________________________________________
Openvpn-devel mailing list
Openvpn-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/openvpn-devel

Reply via email to