From f5c711c8551496a91018ca07e4306f08ede7eef1 Mon Sep 17 00:00:00 2001
From: Jouni Malinen <j@w1.fi>
Date: Sat, 16 Apr 2022 18:48:29 +0300
Subject: [PATCH] OpenSSL: Unload providers only at process exit

The previous mechanism of unloaded the providers from tls_deinit() did
not work correctly for some cases. In particular, it was possible for
hostapd to end up unloading both providers and not being able to recover
from this if TLS server was not enabled.

Address this more cleanly by introducing a new crypto_unload() function
that will be called when the process is exiting.

Fixes: 097ca6bf0b6f ("OpenSSL: Unload providers on deinit")
Signed-off-by: Jouni Malinen <j@w1.fi>
---
 hostapd/main.c                  | 2 ++
 src/crypto/crypto.h             | 8 ++++++++
 src/crypto/crypto_gnutls.c      | 5 +++++
 src/crypto/crypto_internal.c    | 5 +++++
 src/crypto/crypto_libtomcrypt.c | 5 +++++
 src/crypto/crypto_linux.c       | 5 +++++
 src/crypto/crypto_nettle.c      | 5 +++++
 src/crypto/crypto_none.c        | 5 +++++
 src/crypto/crypto_openssl.c     | 8 +++++++-
 src/crypto/crypto_wolfssl.c     | 5 +++++
 src/crypto/tls_openssl.c        | 3 ---
 wpa_supplicant/eapol_test.c     | 2 ++
 wpa_supplicant/main.c           | 2 ++
 wpa_supplicant/preauth_test.c   | 2 ++
 14 files changed, 58 insertions(+), 4 deletions(-)

diff --git a/hostapd/main.c b/hostapd/main.c
index 7c347f905..4503d24ae 100644
--- a/hostapd/main.c
+++ b/hostapd/main.c
@@ -15,6 +15,7 @@
 #include "utils/common.h"
 #include "utils/eloop.h"
 #include "utils/uuid.h"
+#include "crypto/crypto.h"
 #include "crypto/random.h"
 #include "crypto/tls.h"
 #include "common/version.h"
@@ -933,6 +934,7 @@ int main(int argc, char *argv[])
 
 	fst_global_deinit();
 
+	crypto_unload();
 	os_program_deinit();
 
 	return ret;
diff --git a/src/crypto/crypto.h b/src/crypto/crypto.h
index e6150b0cf..410196597 100644
--- a/src/crypto/crypto.h
+++ b/src/crypto/crypto.h
@@ -1275,4 +1275,12 @@ struct wpabuf * crypto_csr_sign(struct crypto_csr *csr,
 				struct crypto_ec_key *key,
 				enum crypto_hash_alg algo);
 
+/**
+ * crypto_unload - Unload crypto resources
+ *
+ * This function is called just before the process exits to allow dynamic
+ * resource allocations to be freed.
+ */
+void crypto_unload(void);
+
 #endif /* CRYPTO_H */
diff --git a/src/crypto/crypto_gnutls.c b/src/crypto/crypto_gnutls.c
index 4ef11462b..a7a163f5c 100644
--- a/src/crypto/crypto_gnutls.c
+++ b/src/crypto/crypto_gnutls.c
@@ -504,3 +504,8 @@ void crypto_cipher_deinit(struct crypto_cipher *ctx)
 	gcry_cipher_close(ctx->dec);
 	os_free(ctx);
 }
+
+
+void crypto_unload(void)
+{
+}
diff --git a/src/crypto/crypto_internal.c b/src/crypto/crypto_internal.c
index aad40af16..d15c363c9 100644
--- a/src/crypto/crypto_internal.c
+++ b/src/crypto/crypto_internal.c
@@ -326,3 +326,8 @@ int crypto_global_init(void)
 void crypto_global_deinit(void)
 {
 }
+
+
+void crypto_unload(void)
+{
+}
diff --git a/src/crypto/crypto_libtomcrypt.c b/src/crypto/crypto_libtomcrypt.c
index ed30efa02..fd79c1a40 100644
--- a/src/crypto/crypto_libtomcrypt.c
+++ b/src/crypto/crypto_libtomcrypt.c
@@ -766,3 +766,8 @@ fail:
 }
 
 #endif /* CONFIG_MODEXP */
+
+
+void crypto_unload(void)
+{
+}
diff --git a/src/crypto/crypto_linux.c b/src/crypto/crypto_linux.c
index 17244561b..9278e2797 100644
--- a/src/crypto/crypto_linux.c
+++ b/src/crypto/crypto_linux.c
@@ -1007,3 +1007,8 @@ int crypto_global_init(void)
 void crypto_global_deinit(void)
 {
 }
+
+
+void crypto_unload(void)
+{
+}
diff --git a/src/crypto/crypto_nettle.c b/src/crypto/crypto_nettle.c
index f85d36532..d74502772 100644
--- a/src/crypto/crypto_nettle.c
+++ b/src/crypto/crypto_nettle.c
@@ -467,3 +467,8 @@ void crypto_cipher_deinit(struct crypto_cipher *ctx)
 {
 	bin_clear_free(ctx, sizeof(*ctx));
 }
+
+
+void crypto_unload(void)
+{
+}
diff --git a/src/crypto/crypto_none.c b/src/crypto/crypto_none.c
index 547919418..a0dc0f52b 100644
--- a/src/crypto/crypto_none.c
+++ b/src/crypto/crypto_none.c
@@ -22,3 +22,8 @@ int des_encrypt(const u8 *clear, const u8 *key, u8 *cypher)
 {
 	return 0;
 }
+
+
+void crypto_unload(void)
+{
+}
diff --git a/src/crypto/crypto_openssl.c b/src/crypto/crypto_openssl.c
index e1b3d15fc..cd7ebf0d9 100644
--- a/src/crypto/crypto_openssl.c
+++ b/src/crypto/crypto_openssl.c
@@ -152,7 +152,7 @@ void openssl_load_legacy_provider(void)
 }
 
 
-void openssl_unload_legacy_provider(void)
+static void openssl_unload_legacy_provider(void)
 {
 #if OPENSSL_VERSION_NUMBER >= 0x30000000L
 	if (openssl_legacy_provider) {
@@ -3797,3 +3797,9 @@ struct wpabuf * crypto_csr_sign(struct crypto_csr *csr,
 }
 
 #endif /* CONFIG_ECC */
+
+
+void crypto_unload(void)
+{
+	openssl_unload_legacy_provider();
+}
diff --git a/src/crypto/crypto_wolfssl.c b/src/crypto/crypto_wolfssl.c
index 00ecf6135..4ae85e083 100644
--- a/src/crypto/crypto_wolfssl.c
+++ b/src/crypto/crypto_wolfssl.c
@@ -1823,3 +1823,8 @@ size_t crypto_ecdh_prime_len(struct crypto_ecdh *ecdh)
 }
 
 #endif /* CONFIG_ECC */
+
+
+void crypto_unload(void)
+{
+}
diff --git a/src/crypto/tls_openssl.c b/src/crypto/tls_openssl.c
index 270d45fa2..e539cbae0 100644
--- a/src/crypto/tls_openssl.c
+++ b/src/crypto/tls_openssl.c
@@ -1128,8 +1128,6 @@ void tls_deinit(void *ssl_ctx)
 
 	tls_openssl_ref_count--;
 	if (tls_openssl_ref_count == 0) {
-		void openssl_unload_legacy_provider(void);
-
 #if OPENSSL_VERSION_NUMBER < 0x10100000L || \
 	(defined(LIBRESSL_VERSION_NUMBER) && \
 	 LIBRESSL_VERSION_NUMBER < 0x20700000L)
@@ -1145,7 +1143,6 @@ void tls_deinit(void *ssl_ctx)
 		tls_global->ocsp_stapling_response = NULL;
 		os_free(tls_global);
 		tls_global = NULL;
-		openssl_unload_legacy_provider();
 	}
 
 	os_free(data->check_cert_subject);
diff --git a/wpa_supplicant/eapol_test.c b/wpa_supplicant/eapol_test.c
index e256ac50e..2289de8e6 100644
--- a/wpa_supplicant/eapol_test.c
+++ b/wpa_supplicant/eapol_test.c
@@ -15,6 +15,7 @@
 #include "common.h"
 #include "utils/ext_password.h"
 #include "common/version.h"
+#include "crypto/crypto.h"
 #include "crypto/tls.h"
 #include "config.h"
 #include "eapol_supp/eapol_supp_sm.h"
@@ -1549,6 +1550,7 @@ int main(int argc, char *argv[])
 	else
 		printf("SUCCESS\n");
 
+	crypto_unload();
 	os_program_deinit();
 
 	return ret;
diff --git a/wpa_supplicant/main.c b/wpa_supplicant/main.c
index 51a8a0298..9229eb51f 100644
--- a/wpa_supplicant/main.c
+++ b/wpa_supplicant/main.c
@@ -12,6 +12,7 @@
 #endif /* __linux__ */
 
 #include "common.h"
+#include "crypto/crypto.h"
 #include "fst/fst.h"
 #include "wpa_supplicant_i.h"
 #include "driver_i.h"
@@ -403,6 +404,7 @@ out:
 #endif /* CONFIG_MATCH_IFACE */
 	os_free(params.pid_file);
 
+	crypto_unload();
 	os_program_deinit();
 
 	return exitcode;
diff --git a/wpa_supplicant/preauth_test.c b/wpa_supplicant/preauth_test.c
index 31b55325f..3ae99da04 100644
--- a/wpa_supplicant/preauth_test.c
+++ b/wpa_supplicant/preauth_test.c
@@ -13,6 +13,7 @@
 #include <assert.h>
 
 #include "common.h"
+#include "crypto/crypto.h"
 #include "config.h"
 #include "eapol_supp/eapol_supp_sm.h"
 #include "eloop.h"
@@ -365,6 +366,7 @@ int main(int argc, char *argv[])
 
 	eloop_destroy();
 
+	crypto_unload();
 	os_program_deinit();
 
 	return ret;