From 693996d5f6fddbb8d152e2980733ebfff5dbdd9f Mon Sep 17 00:00:00 2001
From: Scott Kitterman <scott@kitterman.com>
Date: Tue, 6 Jun 2017 01:05:25 -0400
Subject: [PATCH] Add command line option to dkimsign.py to select signing
 algorithm

---
 ChangeLog   | 1 +
 dkimsign.py | 7 +++++--
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 1ad12db..ca5c121 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -3,6 +3,7 @@ UNRELEASED Version 0.7.0
       is more extensible
     - Add command line options to dkimsign.py to select header and body
       canonicalization algorithmns (LP: #1272724)
+    - Add command line option to dkimsign.py to select signing algorithm
 
 2017-05-30 Version 0.6.2
     - Fixed problem with header folding that caused the first line to be
diff --git a/dkimsign.py b/dkimsign.py
index 115a2d1..b73d0b6 100644
--- a/dkimsign.py
+++ b/dkimsign.py
@@ -44,9 +44,11 @@ parser.add_argument('--hcanon', choices=['simple', 'relaxed'],
 parser.add_argument('--bcanon', choices=['simple', 'relaxed'],
     default='simple',
     help='Body canonicalization algorithm: default=simple')
+parser.add_argument('--signalg', choices=['rsa-sha256', 'rsa-sha1'],
+    default='rsa-sha256',
+    help='Signature algorithm: default=rsa-sha256')
 parser.add_argument('--identity', help='Optional value for i= tag.')
 args=parser.parse_args(arguments)
-signature_algorithm=b'rsa-sha256'
 include_headers = None
 length = None
 logger = None
@@ -58,6 +60,7 @@ if sys.version_info[0] >= 3:
         args.identity = bytes(args.identity, encoding='UTF-8')
     args.hcanon = bytes(args.hcanon, encoding='UTF-8')
     args.bcanon = bytes(args.bcanon, encoding='UTF-8')
+    args.signalg = bytes(args.signalg, encoding='UTF-8')
     # Make sys.stdin and stdout binary streams.
     sys.stdin = sys.stdin.detach()
     sys.stdout = sys.stdout.detach()
@@ -66,7 +69,7 @@ canonicalize = (args.hcanon, args.bcanon)
 message = sys.stdin.read()
 try:
     d = dkim.DKIM(message,logger=logger,
-                  signature_algorithm=signature_algorithm)
+                  signature_algorithm=args.signalg)
     sig = d.sign(args.selector, args.domain, open(
                  args.privatekeyfile, "rb").read(), identity = args.identity,
                  canonicalize=canonicalize, include_headers=include_headers,