Replace asn1_tlc_clear and asn1_tlc_clear_nc macros with a function.

Call the replacement asn1_tlc_invalidate() since it does not actually
clear the ASN1_TLC.

While here, name the ASN1_TLC variables consistently as ctx, remove a
pointless comment and simplify ASN1_item_d2i() slightly.

ok inoguchi@ tb@

diff --git a/lib/libcrypto/asn1/tasn_dec.c b/lib/libcrypto/asn1/tasn_dec.c
index ab3ff8c..331b147 100644 (file)
--- a/lib/libcrypto/asn1/tasn_dec.c
+++ b/lib/libcrypto/asn1/tasn_dec.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: tasn_dec.c,v 1.40 2021/12/03 17:23:16 jsing Exp $ */
+/* $OpenBSD: tasn_dec.c,v 1.41 2021/12/03 17:27:34 jsing Exp $ */
 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
  * project 2000.
  */
@@ -115,45 +115,40 @@ ASN1_tag2bit(int tag)
        return tag2bit[tag];
 }
 
-/* Macro to initialize and invalidate the cache */
-
-#define asn1_tlc_clear(c)      if (c) (c)->valid = 0
-/* Version to avoid compiler warning about 'c' always non-NULL */
-#define asn1_tlc_clear_nc(c)   (c)->valid = 0
-
-/* Decode an ASN1 item, this currently behaves just
- * like a standard 'd2i' function. 'in' points to
- * a buffer to read the data from, in future we will
- * have more advanced versions that can input data
- * a piece at a time and this will simply be a special
- * case.
- */
+static void
+asn1_tlc_invalidate(ASN1_TLC *ctx)
+{
+       if (ctx != NULL)
+               ctx->valid = 0;
+}
 
 ASN1_VALUE *
 ASN1_item_d2i(ASN1_VALUE **pval, const unsigned char **in, long len,
     const ASN1_ITEM *it)
 {
-       ASN1_TLC c;
        ASN1_VALUE *ptmpval = NULL;
+       ASN1_TLC ctx;
 
-       if (!pval)
+       asn1_tlc_invalidate(&ctx);
+
+       if (pval == NULL)
                pval = &ptmpval;
-       asn1_tlc_clear_nc(&c);
-       if (asn1_item_ex_d2i(pval, in, len, it, -1, 0, 0, &c, 0) > 0)
-               return *pval;
-       return NULL;
+       if (asn1_item_ex_d2i(pval, in, len, it, -1, 0, 0, &ctx, 0) <= 0)
+               return NULL;
+
+       return *pval;
 }
 
 int
 ASN1_template_d2i(ASN1_VALUE **pval, const unsigned char **in, long len,
     const ASN1_TEMPLATE *tt)
 {
-       ASN1_TLC c;
+       ASN1_TLC ctx;
 
-       asn1_tlc_clear_nc(&c);
-       return asn1_template_ex_d2i(pval, in, len, tt, 0, &c, 0);
-}
+       asn1_tlc_invalidate(&ctx);
 
+       return asn1_template_ex_d2i(pval, in, len, tt, 0, &ctx, 0);
+}
 
 /* Decode an item, taking care of IMPLICIT tagging, if any.
  * If 'opt' set and tag mismatch return -1 to handle OPTIONAL
@@ -749,10 +744,9 @@ asn1_d2i_ex_primitive(ASN1_VALUE **pval, const unsigned char **in, long inlen,
                 * when we have a exact match wont work
                 */
                if (utype == V_ASN1_OTHER) {
-                       asn1_tlc_clear(ctx);
-               }
-               /* SEQUENCE and SET must be constructed */
-               else if (!cst) {
+                       asn1_tlc_invalidate(ctx);
+               } else if (!cst) {
+                       /* SEQUENCE and SET must be constructed */
                        ASN1error(ASN1_R_TYPE_NOT_CONSTRUCTED);
                        return 0;
                }
@@ -1148,7 +1142,7 @@ asn1_check_tlen(long *olen, int *otag, unsigned char *oclass, char *inf,
                         */
                        if (!(i & 0x81) && ((plen + ctx->hdrlen) > len)) {
                                ASN1error(ASN1_R_TOO_LONG);
-                               asn1_tlc_clear(ctx);
+                               asn1_tlc_invalidate(ctx);
                                return 0;
                        }
                }
@@ -1156,7 +1150,7 @@ asn1_check_tlen(long *olen, int *otag, unsigned char *oclass, char *inf,
 
        if (i & 0x80) {
                ASN1error(ASN1_R_BAD_OBJECT_HEADER);
-               asn1_tlc_clear(ctx);
+               asn1_tlc_invalidate(ctx);
                return 0;
        }
        if (exptag >= 0) {
@@ -1166,13 +1160,13 @@ asn1_check_tlen(long *olen, int *otag, unsigned char *oclass, char *inf,
                         */
                        if (opt)
                                return -1;
-                       asn1_tlc_clear(ctx);
+                       asn1_tlc_invalidate(ctx);
                        ASN1error(ASN1_R_WRONG_TAG);
                        return 0;
                }
                /* We have a tag and class match:
                 * assume we are going to do something with it */
-               asn1_tlc_clear(ctx);
+               asn1_tlc_invalidate(ctx);
        }
 
        if (i & 1)