1 files changed, 104 insertions, 0 deletions
diff --git a/lib/dns/ds.c b/lib/dns/ds.c
new file mode 100644
index 0000000..e994cc5
--- /dev/null
+++ b/lib/dns/ds.c
@@ -0,0 +1,104 @@
+/*
+ * Copyright (C) 2004-2007  Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (C) 2002, 2003  Internet Software Consortium.
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
+ * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
+ * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+ * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
+ * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/* $Id: ds.c,v 1.11 2007/06/19 23:47:16 tbox Exp $ */
+
+/*! \file */
+
+#include <config.h>
+
+#include <string.h>
+
+#include <isc/buffer.h>
+#include <isc/region.h>
+#include <isc/sha1.h>
+#include <isc/sha2.h>
+#include <isc/util.h>
+
+#include <dns/ds.h>
+#include <dns/fixedname.h>
+#include <dns/name.h>
+#include <dns/rdata.h>
+#include <dns/rdatastruct.h>
+#include <dns/result.h>
+
+#include <dst/dst.h>
+
+isc_result_t
+dns_ds_buildrdata(dns_name_t *owner, dns_rdata_t *key,
+		  unsigned int digest_type, unsigned char *buffer,
+		  dns_rdata_t *rdata)
+{
+	dns_fixedname_t fname;
+	dns_name_t *name;
+	unsigned char digest[ISC_SHA256_DIGESTLENGTH];
+	isc_region_t r;
+	isc_buffer_t b;
+	dns_rdata_ds_t ds;
+
+	REQUIRE(key != NULL);
+	REQUIRE(key->type == dns_rdatatype_dnskey);
+
+	if (!dns_ds_digest_supported(digest_type))
+		return (ISC_R_NOTIMPLEMENTED);
+
+	dns_fixedname_init(&fname);
+	name = dns_fixedname_name(&fname);
+	(void)dns_name_downcase(owner, name, NULL);
+
+	memset(buffer, 0, DNS_DS_BUFFERSIZE);
+	isc_buffer_init(&b, buffer, DNS_DS_BUFFERSIZE);
+
+	if (digest_type == DNS_DSDIGEST_SHA1) {
+		isc_sha1_t sha1;
+		isc_sha1_init(&sha1);
+		dns_name_toregion(name, &r);
+		isc_sha1_update(&sha1, r.base, r.length);
+		dns_rdata_toregion(key, &r);
+		INSIST(r.length >= 4);
+		isc_sha1_update(&sha1, r.base, r.length);
+		isc_sha1_final(&sha1, digest);
+	} else {
+		isc_sha256_t sha256;
+		isc_sha256_init(&sha256);
+		dns_name_toregion(name, &r);
+		isc_sha256_update(&sha256, r.base, r.length);
+		dns_rdata_toregion(key, &r);
+		INSIST(r.length >= 4);
+		isc_sha256_update(&sha256, r.base, r.length);
+		isc_sha256_final(digest, &sha256);
+	}
+
+	ds.mctx = NULL;
+	ds.common.rdclass = key->rdclass;
+	ds.common.rdtype = dns_rdatatype_ds;
+	ds.algorithm = r.base[3];
+	ds.key_tag = dst_region_computeid(&r, ds.algorithm);
+	ds.digest_type = digest_type;
+	ds.length = (digest_type == DNS_DSDIGEST_SHA1) ?
+		    ISC_SHA1_DIGESTLENGTH : ISC_SHA256_DIGESTLENGTH;
+	ds.digest = digest;
+
+	return (dns_rdata_fromstruct(rdata, key->rdclass, dns_rdatatype_ds,
+				     &ds, &b));
+}
+
+isc_boolean_t
+dns_ds_digest_supported(unsigned int digest_type) {
+	return  (ISC_TF(digest_type == DNS_DSDIGEST_SHA1 ||
+			digest_type == DNS_DSDIGEST_SHA256));
+}