upstream: some more corrections for documentation problems spotted

by Ron Frederick

document certifiate private key format
correct flags type for sk-ssh-ed25519@openssh.com keys

OpenBSD-Commit-ID: fc4e9a1ed7f9f7f9dd83e2e2c59327912e933e74

diff --git a/PROTOCOL.u2f b/PROTOCOL.u2f
index 823f53634aa7d5390fabdf0718064852ece6892d..32bfa20f3160b1eeccd718f1914dbe5e1022311c 100644 (file)
--- a/PROTOCOL.u2f
+++ b/PROTOCOL.u2f
@@ -86,7 +86,7 @@ With a private half consisting of:
        string          "sk-ssh-ed25519@openssh.com"
        string          public key
        string          application (user-specified, but typically "ssh:")
-       uint32          flags
+       uint8           flags
        string          key_handle
        string          reserved
 
@@ -110,6 +110,8 @@ information to the public key:
        string          signature key
        string          signature
 
+and for security key ed25519 certificates:
+
        string          "sk-ssh-ed25519-cert-v01@openssh.com"
        string          nonce
        string          public key
@@ -126,6 +128,15 @@ information to the public key:
        string          signature key
        string          signature
 
+Both security key certificates use the following encoding for private keys:
+
+       string          type (e.g. "sk-ssh-ed25519-cert-v01@openssh.com")
+       string          pubkey (the above key/cert structure)
+       string          application
+       uint8           flags
+       string          key_handle
+       string          reserved
+
 During key generation, the hardware also returns attestation information
 that may be used to cryptographically prove that a given key is
 hardware-backed. Unfortunately, the protocol required for this proof is
@@ -188,7 +199,6 @@ For Ed25519 keys the signature is encoded as:
        byte            flags
        uint32          counter
 
-
 ssh-agent protocol extensions
 -----------------------------