Improve error checking in i2d_ASN1_bio_stream()

The streaming BIO API is full of missing error checks. This diff reverts
the logic so that the single call to ASN1_item_i2d_bio() is error checked
(it has the usual 1/0 return values), unindents the bulk of the code and
propagates the SMIME_crlf_copy() return value (alos 1/0) to be the actual
error.

ok jsing

diff --git a/lib/libcrypto/asn1/asn_mime.c b/lib/libcrypto/asn1/asn_mime.c
index 56a428a..5418535 100644 (file)
--- a/lib/libcrypto/asn1/asn_mime.c
+++ b/lib/libcrypto/asn1/asn_mime.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: asn_mime.c,v 1.32 2023/07/05 21:23:36 beck Exp $ */
+/* $OpenBSD: asn_mime.c,v 1.33 2024/03/29 03:23:01 tb Exp $ */
 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
  * project.
  */
@@ -118,29 +118,30 @@ int
 i2d_ASN1_bio_stream(BIO *out, ASN1_VALUE *val, BIO *in, int flags,
     const ASN1_ITEM *it)
 {
-       /* If streaming create stream BIO and copy all content through it */
-       if (flags & SMIME_STREAM) {
-               BIO *bio, *tbio;
-               bio = BIO_new_NDEF(out, val, it);
-               if (!bio) {
-                       ASN1error(ERR_R_MALLOC_FAILURE);
-                       return 0;
-               }
-               SMIME_crlf_copy(in, bio, flags);
-               (void)BIO_flush(bio);
-               /* Free up successive BIOs until we hit the old output BIO */
-               do {
-                       tbio = BIO_pop(bio);
-                       BIO_free(bio);
-                       bio = tbio;
-               } while (bio != out);
+       BIO *bio, *tbio;
+       int ret;
+
+       /* Without streaming, write out the ASN.1 structure's content. */
+       if ((flags & SMIME_STREAM) == 0)
+               return ASN1_item_i2d_bio(it, out, val);
+
+       /* If streaming, create a stream BIO and copy all content through it. */
+       if ((bio = BIO_new_NDEF(out, val, it)) == NULL) {
+               ASN1error(ERR_R_MALLOC_FAILURE);
+               return 0;
        }
-       /* else just write out ASN1 structure which will have all content
-        * stored internally
-        */
-       else
-               ASN1_item_i2d_bio(it, out, val);
-       return 1;
+
+       ret = SMIME_crlf_copy(in, bio, flags);
+       (void)BIO_flush(bio);
+
+       /* Free up successive BIOs until we hit the old output BIO. */
+       do {
+               tbio = BIO_pop(bio);
+               BIO_free(bio);
+               bio = tbio;
+       } while (bio != out);
+
+       return ret;
 }
 
 /* Base 64 read and write of ASN1 structure */