Add "origin" field to EVP_CIPHER, EVP_MD

Add a "where did this EVP_{CIPHER,MD} come from" flag: global, via fetch,
or via EVP_{CIPHER,MD}_meth_new.  Update EVP_{CIPHER,MD}_free to handle all
three origins. The flag is deliberately right before some function pointers,
so that compile-time failures (int/pointer) will occur, as opposed to
taking a bit in the existing "flags" field.  The "global variable" flag
is non-zero, so the default case of using OPENSSL_zalloc (for provider
ciphers), will do the right thing. Ref-counting is a no-op for
Make up_ref no-op for global MD and CIPHER objects

Deprecate EVP_MD_CTX_md().  Added EVP_MD_CTX_get0_md() (same semantics as
the deprecated function) and EVP_MD_CTX_get1_md().  Likewise, deprecate
EVP_CIPHER_CTX_cipher() in favor of EVP_CIPHER_CTX_get0_cipher(), and add
EVP_CIPHER_CTX_get1_CIPHER().

Refactor EVP_MD_free() and EVP_MD_meth_free() to call new common
evp_md_free_int() function.
Refactor EVP_CIPHER_free() and EVP_CIPHER_meth_free() to call new common
evp_cipher_free_int() function.

Also change some flags tests to explicit test == or != zero. E.g.,
        if (flags & x) --> if ((flags & x) != 0)
        if (!(flags & x)) --> if ((flags & x) == 0)
Only done for those lines where "get0_cipher" calls were made.

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/14193)

1 files changed, 13 insertions, 6 deletions

diff --git a/crypto/evp/evp_enc.c b/crypto/evp/evp_enc.c
index 9073312dfd..2de2a11e5a 100644
--- a/crypto/evp/evp_enc.c
+++ b/crypto/evp/evp_enc.c
@@ -325,7 +325,8 @@ static int evp_cipher_init_internal(EVP_CIPHER_CTX *ctx,
         return 0;
     }
 
-    if (!(EVP_CIPHER_flags(EVP_CIPHER_CTX_cipher(ctx)) & EVP_CIPH_CUSTOM_IV)) {
+    if ((EVP_CIPHER_flags(EVP_CIPHER_CTX_get0_cipher(ctx))
+                & EVP_CIPH_CUSTOM_IV) == 0) {
         switch (EVP_CIPHER_CTX_mode(ctx)) {
 
         case EVP_CIPH_STREAM_CIPHER:
@@ -1602,23 +1603,29 @@ int EVP_CIPHER_up_ref(EVP_CIPHER *cipher)
 {
     int ref = 0;
 
-    CRYPTO_UP_REF(&cipher->refcnt, &ref, cipher->lock);
+    if (cipher->origin == EVP_ORIG_DYNAMIC)
+        CRYPTO_UP_REF(&cipher->refcnt, &ref, cipher->lock);
     return 1;
 }
 
+void evp_cipher_free_int(EVP_CIPHER *cipher)
+{
+    ossl_provider_free(cipher->prov);
+    CRYPTO_THREAD_lock_free(cipher->lock);
+    OPENSSL_free(cipher);
+}
+
 void EVP_CIPHER_free(EVP_CIPHER *cipher)
 {
     int i;
 
-    if (cipher == NULL || cipher->prov == NULL)
+    if (cipher == NULL || cipher->origin != EVP_ORIG_DYNAMIC)
         return;
 
     CRYPTO_DOWN_REF(&cipher->refcnt, &i, cipher->lock);
     if (i > 0)
         return;
-    ossl_provider_free(cipher->prov);
-    CRYPTO_THREAD_lock_free(cipher->lock);
-    OPENSSL_free(cipher);
+    evp_cipher_free_int(cipher);
 }
 
 void EVP_CIPHER_do_all_provided(OSSL_LIB_CTX *libctx,