upstream: U2F/FIDO middleware interface

Supports enrolling (generating) keys and signatures.

feedback & ok markus@

OpenBSD-Commit-ID: 73d1dd5939454f9c7bd840f48236cba41e8ad592

1 files changed, 63 insertions, 0 deletions

diff --git a/sk-api.h b/sk-api.h
new file mode 100644
index 00000000..1de73342
--- /dev/null
+++ b/sk-api.h
@@ -0,0 +1,63 @@
+/* $OpenBSD: sk-api.h,v 1.1 2019/10/31 21:16:20 djm Exp $ */
+/*
+ * Copyright (c) 2019 Google LLC
+ *
+ * Permission to use, copy, modify, and 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 THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR 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.
+ */
+
+#ifndef _SK_API_H
+#define _SK_API_H 1
+
+#include <stddef.h>
+#include <stdint.h>
+
+/* Flags */
+#define SSH_SK_USER_PRESENCE_REQD	0x01
+
+struct sk_enroll_response {
+	uint8_t *public_key;
+	size_t public_key_len;
+	uint8_t *key_handle;
+	size_t key_handle_len;
+	uint8_t *signature;
+	size_t signature_len;
+	uint8_t *attestation_cert;
+	size_t attestation_cert_len;
+};
+
+struct sk_sign_response {
+	uint8_t flags;
+	uint32_t counter;
+	uint8_t *sig_r;
+	size_t sig_r_len;
+	uint8_t *sig_s;
+	size_t sig_s_len;
+};
+
+#define SSH_SK_VERSION_MAJOR		0x00010000 /* current API version */
+#define SSH_SK_VERSION_MAJOR_MASK	0xffff0000
+
+/* Return the version of the middleware API */
+uint32_t sk_api_version(void);
+
+/* Enroll a U2F key (private key generation) */
+int sk_enroll(const uint8_t *challenge, size_t challenge_len,
+    const char *application, uint8_t flags,
+    struct sk_enroll_response **enroll_response);
+
+/* Sign a challenge */
+int sk_sign(const uint8_t *message, size_t message_len,
+    const char *application, const uint8_t *key_handle, size_t key_handle_len,
+    uint8_t flags, struct sk_sign_response **sign_response);
+
+#endif /* _SK_API_H */