add Linux_i686

Linux_i686/bin/edsig

@@ -0,0 +1,88 @@
+#!/usr/bin/python
+
+import os, sys
+import ed25519
+from hashlib import sha256
+
+def help():
+    print """\
+Usage: (ed25519 version %s)
+
+ edsig generate [STEM]
+   creates keypair, writes to 'STEM.signing.key' and 'STEM.verifying.key'
+   default is to 'signing.key' and 'verifying.key'
+
+ edsig sign (signing.key|keyfile) message.file
+   prints signature to stdout
+   If message.file is "-", reads from stdin.
+
+ edsig verify (verifying.key|keyfile) message.file (signature|sigfile)
+   prints 'good signature!' or raises exception
+   If message.file is "-", reads from stdin.
+
+Key-providing arguments can either be the key itself, or point to a file
+containing the key.
+""" % ed25519.__version__
+
+def remove_prefix(prefix, s):
+    if not s.startswith(prefix):
+        raise ValueError("no prefix found")
+    return s[len(prefix):]
+
+def data_from_arg(arg, prefix, keylen, readable):
+    if (readable
+        and arg.startswith(prefix)
+        and len(remove_prefix(prefix, arg))==keylen):
+        return arg
+    if os.path.isfile(arg):
+        return open(arg,"r").read()
+    raise ValueError("unable to get data from '%s'" % arg)
+
+def message_rep(msg_arg):
+    if msg_arg == "-":
+        f = sys.stdin
+    else:
+        f = open(msg_arg, "rb")
+    h = sha256()
+    while True:
+        data = f.read(16*1024)
+        if not data:
+            break
+        h.update(data)
+    return h.digest()
+
+if len(sys.argv) < 2:
+    help()
+elif sys.argv[1] == "generate":
+    sk,vk = ed25519.create_keypair()
+    if len(sys.argv) > 2:
+        sk_outfile = sys.argv[2]+".signing.key"
+        vk_outfile = sys.argv[2]+".verifying.key"
+    else:
+        sk_outfile = "signing.key"
+        vk_outfile = "verifying.key"
+    sk_s = sk.to_seed(prefix="sign0-")
+    vk_s = vk.to_ascii("verf0-", "base32")
+    open(sk_outfile,"w").write(sk_s)
+    open(vk_outfile,"w").write(vk_s+"\n")
+    print "wrote private signing key to", sk_outfile
+    print "write public verifying key to", vk_outfile
+elif sys.argv[1] == "sign":
+    sk_arg = sys.argv[2]
+    msg_arg = sys.argv[3]
+    sk = ed25519.SigningKey(data_from_arg(sk_arg, "sign0-", 52, False),
+                            prefix="sign0-")
+    sig = sk.sign(message_rep(msg_arg), prefix="sig0-", encoding="base32")
+    print sig
+elif sys.argv[1] == "verify":
+    vk_arg = sys.argv[2]
+    msg_arg = sys.argv[3]
+    sig_arg = sys.argv[4]
+    vk = ed25519.VerifyingKey(data_from_arg(vk_arg, "verf0-", 52, True),
+                              prefix="verf0-", encoding="base32")
+    sig = data_from_arg(sig_arg, "sig0-", 103, True)
+    vk.verify(sig, message_rep(msg_arg),
+              prefix="sig0-", encoding="base32") # could raise BadSignature
+    print "good signature!"
+else:
+    help()