Provide t2i_ASN1_OBJECT_internal() and use it for OBJ_txt2obj()

The current OBJ_txt2obj() implementation converts the text to ASN.1
object content octets, builds a full DER encoding from it, then feeds
the entire thing back through the DER to ASN.1 object conversion. Rather
than doing this crazy dance, provide an t2i_ASN1_OBJECT_internal() function
that converts the text to ASN.1 object content octets, then creates a new
ASN1_OBJECT and attaches the content octets to it.

ok inoguchi@ tb@

1 files changed, 38 insertions, 1 deletions

diff --git a/src/lib/libcrypto/asn1/a_object.c b/src/lib/libcrypto/asn1/a_object.c
index 0061ccb880..56a08a3cb4 100644
--- a/src/lib/libcrypto/asn1/a_object.c
+++ b/src/lib/libcrypto/asn1/a_object.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: a_object.c,v 1.42 2022/03/19 17:35:52 jsing Exp $ */
+/* $OpenBSD: a_object.c,v 1.43 2022/03/19 17:49:32 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -475,6 +475,43 @@ i2t_ASN1_OBJECT(char *buf, int buf_len, const ASN1_OBJECT *aobj)
         return i2t_ASN1_OBJECT_internal(aobj, buf, buf_len, 0);
 }
 
+ASN1_OBJECT *
+t2i_ASN1_OBJECT_internal(const char *oid)
+{
+        ASN1_OBJECT *aobj = NULL;
+        uint8_t *data = NULL;
+        size_t data_len;
+        CBB cbb;
+        CBS cbs;
+
+        memset(&cbb, 0, sizeof(cbb));
+
+        CBS_init(&cbs, oid, strlen(oid));
+
+        if (!CBB_init(&cbb, 0))
+                goto err;
+        if (!a2c_ASN1_OBJECT_internal(&cbb, &cbs))
+                goto err;
+        if (!CBB_finish(&cbb, &data, &data_len))
+                goto err;
+
+        if (data_len > INT_MAX)
+                goto err;
+
+        if ((aobj = ASN1_OBJECT_new()) == NULL)
+                goto err;
+
+        aobj->data = data;
+        aobj->length = (int)data_len;
+        data = NULL;
+
+ err:
+        CBB_cleanup(&cbb);
+        free(data);
+
+        return aobj;
+}
+
 int
 i2a_ASN1_OBJECT(BIO *bp, const ASN1_OBJECT *aobj)
 {