Remove/combine redundant call of EVP_CipherInit before EVP_CipherInit_Ex

EVP_CipherInit basically is the same EVP_CipherInit_ex except that it
in some instances it resets/inits the ctx parameter first. We already
call EVP_CIPHER_CTX_reset to reset/init the ctx before. Also ensure that
EVP_CipherInit_Ex gets the cipher to actually be able to initialise the
context.

OpenSSL 1.0.2:

https://github.com/openssl/openssl/blob/OpenSSL_1_0_2-stable/crypto/evp/evp_enc.c#L94

EVP_CipherInit calls first EVP_CIPHER_CTX_init and then EVP_CipherInit_ex

Our openssl_compat.h has

for these older OpenSSL versions

OpenSSL 3.0:

https://github.com/openssl/openssl/blob/openssl-3.2/crypto/evp/evp_enc.c#L450

basically the same as 1.0.2. Just that method names have been changed.

Change-Id: I911e25949a8647b567fd4178683534d4404ab469
Signed-off-by: Arne Schwabe <arne@rfc2549.org>
Acked-by: Gert Doering <gert@greenie.muc.de>
Message-Id: <20240402134909.6340-1-gert@greenie.muc.de>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg28523.html
Signed-off-by: Gert Doering <gert@greenie.muc.de>

diff --git a/src/openvpn/crypto_openssl.c b/src/openvpn/crypto_openssl.c
index bfc5e37b82c54db97e428e3681770ada72ff7ea8..b2c4eb6413f30a5b15f66b5d2024cf84bb602f75 100644 (file)
--- a/src/openvpn/crypto_openssl.c
+++ b/src/openvpn/crypto_openssl.c
@@ -846,11 +846,7 @@ cipher_ctx_init(EVP_CIPHER_CTX *ctx, const uint8_t *key,
     evp_cipher_type *kt = cipher_get(ciphername);
 
     EVP_CIPHER_CTX_reset(ctx);
-    if (!EVP_CipherInit(ctx, kt, NULL, NULL, enc))
-    {
-        crypto_msg(M_FATAL, "EVP cipher init #1");
-    }
-    if (!EVP_CipherInit_ex(ctx, NULL, NULL, key, NULL, enc))
+    if (!EVP_CipherInit_ex(ctx, kt, NULL, key, NULL, enc))
     {
         crypto_msg(M_FATAL, "EVP cipher init #2");
     }