1 files changed, 71 insertions, 0 deletions

diff --git a/source4/auth/gensec/gensec_krb5.c b/source4/auth/gensec/gensec_krb5.c
index 9939105ad5..ca933f5b0f 100644
--- a/source4/auth/gensec/gensec_krb5.c
+++ b/source4/auth/gensec/gensec_krb5.c
@@ -39,6 +39,7 @@
 #include "param/param.h"
 #include "auth/auth_sam_reply.h"
 #include "lib/util/util_net.h"
+#include "../lib/util/asn1.h"
 
 _PUBLIC_ NTSTATUS gensec_krb5_init(void);
 
@@ -392,6 +393,76 @@ static NTSTATUS gensec_fake_gssapi_krb5_client_start(struct gensec_security *gen
 	return gensec_krb5_common_client_start(gensec_security, true);
 }
 
+
+/*
+  generate a krb5 GSS-API wrapper packet given a ticket
+*/
+static DATA_BLOB gensec_gssapi_gen_krb5_wrap(TALLOC_CTX *mem_ctx, const DATA_BLOB *ticket, const uint8_t tok_id[2])
+{
+	struct asn1_data *data;
+	DATA_BLOB ret;
+
+	data = asn1_init(mem_ctx);
+	if (!data || !ticket->data) {
+		return data_blob(NULL,0);
+	}
+
+	asn1_push_tag(data, ASN1_APPLICATION(0));
+	asn1_write_OID(data, GENSEC_OID_KERBEROS5);
+
+	asn1_write(data, tok_id, 2);
+	asn1_write(data, ticket->data, ticket->length);
+	asn1_pop_tag(data);
+
+	if (data->has_error) {
+		DEBUG(1,("Failed to build krb5 wrapper at offset %d\n", (int)data->ofs));
+		asn1_free(data);
+		return data_blob(NULL,0);
+	}
+
+	ret = data_blob_talloc(mem_ctx, data->data, data->length);
+	asn1_free(data);
+
+	return ret;
+}
+
+/*
+  parse a krb5 GSS-API wrapper packet giving a ticket
+*/
+static bool gensec_gssapi_parse_krb5_wrap(TALLOC_CTX *mem_ctx, const DATA_BLOB *blob, DATA_BLOB *ticket, uint8_t tok_id[2])
+{
+	bool ret;
+	struct asn1_data *data = asn1_init(mem_ctx);
+	int data_remaining;
+
+	if (!data) {
+		return false;
+	}
+
+	asn1_load(data, *blob);
+	asn1_start_tag(data, ASN1_APPLICATION(0));
+	asn1_check_OID(data, GENSEC_OID_KERBEROS5);
+
+	data_remaining = asn1_tag_remaining(data);
+
+	if (data_remaining < 3) {
+		data->has_error = true;
+	} else {
+		asn1_read(data, tok_id, 2);
+		data_remaining -= 2;
+		*ticket = data_blob_talloc(mem_ctx, NULL, data_remaining);
+		asn1_read(data, ticket->data, ticket->length);
+	}
+
+	asn1_end_tag(data);
+
+	ret = !data->has_error;
+
+	asn1_free(data);
+
+	return ret;
+}
+
 /**
  * Next state function for the Krb5 GENSEC mechanism
  *