Unbreak ASN.1 indefinite length encoding.

In r1.25 of tasn_enc.c a check was added to ensure that asn1_ex_i2c()
returned the same value on both calls, however in the ndef case the len
variable gets changed between calls. Keep a copy of the original value to
test against.

Issue reported by niklas, who encountered a test failure in rust-openssl.

ok miod@ tb@

diff --git a/lib/libcrypto/asn1/tasn_enc.c b/lib/libcrypto/asn1/tasn_enc.c
index d42c5ea..e0f26b9 100644 (file)
--- a/lib/libcrypto/asn1/tasn_enc.c
+++ b/lib/libcrypto/asn1/tasn_enc.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: tasn_enc.c,v 1.25 2022/08/20 17:55:08 jsing Exp $ */
+/* $OpenBSD: tasn_enc.c,v 1.26 2022/10/17 18:03:15 jsing Exp $ */
 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
  * project 2000.
  */
@@ -494,7 +494,7 @@ static int
 asn1_i2d_ex_primitive(ASN1_VALUE **pval, unsigned char **out,
     const ASN1_ITEM *it, int tag, int aclass)
 {
-       int len;
+       int olen, len;
        int utype;
        int usetag;
        int ndef = 0;
@@ -505,7 +505,7 @@ asn1_i2d_ex_primitive(ASN1_VALUE **pval, unsigned char **out,
         * out the underlying type.
         */
 
-       len = asn1_ex_i2c(pval, NULL, &utype, it);
+       olen = len = asn1_ex_i2c(pval, NULL, &utype, it);
 
        /* If SEQUENCE, SET or OTHER then header is
         * included in pseudo content octets so don't
@@ -541,7 +541,7 @@ asn1_i2d_ex_primitive(ASN1_VALUE **pval, unsigned char **out,
        if (out) {
                if (usetag)
                        ASN1_put_object(out, ndef, len, tag, aclass);
-               if (asn1_ex_i2c(pval, *out, &utype, it) != len)
+               if (asn1_ex_i2c(pval, *out, &utype, it) != olen)
                        return -1;
                if (ndef)
                        ASN1_put_eoc(out);