Merge pull request #19 from hlandauf/master

Add SSHFP

ifa-0001.md

@@ -460,7 +460,7 @@ Except where otherwise specified, any item with a value of `null` SHALL be treat
 
     The value for this item SHALL be of one of the following forms:
     
-    - An array of zero or more value. Each such value SHALL be a string conforming to the textual format specified in RFC 1876 s. 3 for the type-specific data.
+    - An array of zero or more values. Each such value SHALL be a string conforming to the textual format specified in RFC 1876 s. 3 for the type-specific data.
 
     - A string. Where this form is encountered, it SHALL be substituted with an array containing that string and be processed as though that was what as encountered, as per the above form.
 
@@ -473,6 +473,29 @@ Except where otherwise specified, any item with a value of `null` SHALL be treat
 
         "loc": "10 Downing Street"
 
+  - "sshfp": Used to identify zero or more SSH server key fingerprints. This item shall map to zero or more DNS resource records of type "SSHFP", and is semantically equivalent to that set of resource records.
+
+    The value for this item SHALL be one of the following forms:
+
+    - An array of zero or more items. Each such value shall represent a SSHFP record, and SHALL be of the following form:
+
+      - An array of at least three values.
+
+        The first value SHALL be a non-negative integer expressible in 8 bits expressing the Algorithm field of the SSHFP record (RFC 4255 s. 3.1.1).
+
+        The second value SHALL be a non-negative integer expressible in 8 bits expressing the Fingerprint Type field of the SSHFP record (RFC 4255 s. 3.1.2).
+
+        The third value SHALL be a string containing the base64 encoding of the Fingerprint field of the SSHFP record (RFC 4255 s. 3.1.3).
+
+        The textual expression of this field in RFC 4255 uses hex encoding. Therefore this field must be converted to the correct form by decoding it and reencoding it using base64.
+
+        Any additional values in the array beyond the first three MUST be ignored.
+
+    Examples:
+
+        "sshfp": []
+        "sshfp": [[2,1,"EjRWeJq83vZ4kBI0VniavN72eJA="]]  // conversion of example at RFC 4255 s. 3.1.2
+
 #### Administrative Constructs
 
   - "info": This optional item can be used to provide WHOIS-like information.