Add EVP_CIPHER_CTX_tag_length()

There is no deprecated CTRL support for this new field.

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/9698)

2 files changed, 13 insertions, 0 deletions

diff --git a/crypto/evp/evp_lib.c b/crypto/evp/evp_lib.c
index 9c3edb3322..5be04b0502 100644
--- a/crypto/evp/evp_lib.c
+++ b/crypto/evp/evp_lib.c
@@ -336,6 +336,17 @@ legacy:
     return v;
 }
 
+int EVP_CIPHER_CTX_tag_length(const EVP_CIPHER_CTX *ctx)
+{
+    int ret;
+    size_t v = 0;
+    OSSL_PARAM params[2] = { OSSL_PARAM_END, OSSL_PARAM_END };
+
+    params[0] = OSSL_PARAM_construct_size_t(OSSL_CIPHER_PARAM_AEAD_TAGLEN, &v);
+    ret = evp_do_ciph_ctx_getparams(ctx->cipher, ctx->provctx, params);
+    return ret == 1 ? (int)v : 0;
+}
+
 const unsigned char *EVP_CIPHER_CTX_original_iv(const EVP_CIPHER_CTX *ctx)
 {
     return ctx->oiv;
diff --git a/crypto/evp/evp_utils.c b/crypto/evp/evp_utils.c
index e5cd5b84e1..3da208a69f 100644
--- a/crypto/evp/evp_utils.c
+++ b/crypto/evp/evp_utils.c
@@ -25,6 +25,8 @@
  * use the same value, and other callers will have to compensate.
  */
 #define PARAM_CHECK(obj, func, errfunc)                                        \
+    if (obj == NULL)                                                           \
+        return 0;                                                              \
     if (obj->prov == NULL)                                                     \
         return EVP_CTRL_RET_UNSUPPORTED;                                       \
     if (obj->func == NULL) {                                                   \