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@

Author: jsing

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)
 {

src/lib/libcrypto/asn1/asn1_locl.h

@@ -1,4 +1,4 @@
-/* $OpenBSD: asn1_locl.h,v 1.22 2022/03/13 14:58:14 jsing Exp $ */
+/* $OpenBSD: asn1_locl.h,v 1.23 2022/03/19 17:49:32 jsing Exp $ */
 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
  * project 2006.
  */
@@ -201,5 +201,6 @@ int asn1_tag2charwidth(int tag);
 
 int i2t_ASN1_OBJECT_internal(const ASN1_OBJECT *aobj, char *buf, int buf_len,
     int no_name);
+ASN1_OBJECT *t2i_ASN1_OBJECT_internal(const char *oid);
 
 __END_HIDDEN_DECLS

src/lib/libcrypto/objects/obj_dat.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: obj_dat.c,v 1.48 2022/03/02 11:28:00 jsing Exp $ */
+/* $OpenBSD: obj_dat.c,v 1.49 2022/03/19 17:49:32 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -485,42 +485,15 @@ OBJ_obj2nid(const ASN1_OBJECT *a)
 ASN1_OBJECT *
 OBJ_txt2obj(const char *s, int no_name)
 {
-	int nid = NID_undef;
-	ASN1_OBJECT *op = NULL;
-	unsigned char *buf;
-	unsigned char *p;
-	const unsigned char *cp;
-	int i, j;
+	int nid;
 
 	if (!no_name) {
 		if (((nid = OBJ_sn2nid(s)) != NID_undef) ||
 		    ((nid = OBJ_ln2nid(s)) != NID_undef) )
 			return OBJ_nid2obj(nid);
 	}
 
-	/* Work out size of content octets */
-	i = a2d_ASN1_OBJECT(NULL, 0, s, -1);
-	if (i <= 0) {
-		/* Don't clear the error */
-		/*ERR_clear_error();*/
-		return NULL;
-	}
-	/* Work out total size */
-	j = ASN1_object_size(0, i, V_ASN1_OBJECT);
-
-	if ((buf = malloc(j)) == NULL)
-		return NULL;
-
-	p = buf;
-	/* Write out tag+length */
-	ASN1_put_object(&p, 0, i, V_ASN1_OBJECT, V_ASN1_UNIVERSAL);
-	/* Write out contents */
-	a2d_ASN1_OBJECT(p, i, s, -1);
-
-	cp = buf;
-	op = d2i_ASN1_OBJECT(NULL, &cp, j);
-	free(buf);
-	return op;
+	return t2i_ASN1_OBJECT_internal(s);
 }
 
 int