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@

1 files changed, 26 insertions, 32 deletions

diff --git a/src/lib/libcrypto/asn1/tasn_dec.c b/src/lib/libcrypto/asn1/tasn_dec.c
index ab3ff8c3bc..331b147936 100644
--- a/src/lib/libcrypto/asn1/tasn_dec.c
+++ b/src/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)