diff options
| author | Robey Pointer <robey@lag.net> | 2005-10-17 16:36:55 +0000 |
|---|---|---|
| committer | Robey Pointer <robey@lag.net> | 2005-10-17 16:36:55 +0000 |
| commit | 64d89583c73dda6c22136f3bc138d209835c68b1 (patch) | |
| tree | 0f023bd6d62b8be5d1df66c046e7c4bfc5706467 | |
| parent | 6eab0b3b4df096aa6b9421c8fe342078d182c523 (diff) | |
[project @ Arch-1:robey@lag.net--2005-master-shake%paramiko--dev--1--patch-66]
fix a test that failed once: the encoding of R or S in dss signatures might not always be exactly 20 bytes
| -rw-r--r-- | paramiko/dsskey.py | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/paramiko/dsskey.py b/paramiko/dsskey.py index 6e94d814..35bf08c0 100644 --- a/paramiko/dsskey.py +++ b/paramiko/dsskey.py @@ -88,14 +88,21 @@ class DSSKey (PKey): dss = DSA.construct((long(self.y), long(self.g), long(self.p), long(self.q), long(self.x))) # generate a suitable k qsize = len(util.deflate_long(self.q, 0)) - while 1: + while True: k = util.inflate_long(rpool.get_bytes(qsize), 1) if (k > 2) and (k < self.q): break r, s = dss.sign(util.inflate_long(digest, 1), k) m = Message() m.add_string('ssh-dss') - m.add_string(util.deflate_long(r, 0) + util.deflate_long(s, 0)) + # apparently, in rare cases, r or s may be shorter than 20 bytes! + rstr = util.deflate_long(r, 0) + sstr = util.deflate_long(s, 0) + if len(rstr) < 20: + rstr = '\x00' * (20 - len(rstr)) + rstr + if len(sstr) < 20: + sstr = '\x00' * (20 - len(sstr)) + sstr + m.add_string(rstr + sstr) return m def verify_ssh_sig(self, data, msg): |