summaryrefslogtreecommitdiffhomepage
path: root/demo.py
blob: 963f7d83a3d44868b03dc4114e43c9c4fa939dc5 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
#!/usr/bin/python

import sys, os, socket, threading, getpass, logging, time, base64, select, termios, tty, traceback
import paramiko


#####   utility functions

def load_host_keys():
    filename = os.environ['HOME'] + '/.ssh/known_hosts'
    keys = {}
    try:
        f = open(filename, 'r')
    except Exception, e:
        print '*** Unable to open host keys file (%s)' % filename
        return
    for line in f:
        keylist = line.split(' ')
        if len(keylist) != 3:
            continue
        hostlist, keytype, key = keylist
        hosts = hostlist.split(',')
        for host in hosts:
            if not keys.has_key(host):
                keys[host] = {}
            keys[host][keytype] = base64.decodestring(key)
    f.close()
    return keys


#####   main demo

# setup logging
l = logging.getLogger("paramiko")
l.setLevel(logging.DEBUG)
if len(l.handlers) == 0:
    f = open('demo.log', 'w')
    lh = logging.StreamHandler(f)
    lh.setFormatter(logging.Formatter('%(levelname)-.3s [%(asctime)s] %(name)s: %(message)s', '%Y%m%d:%H%M%S'))
    l.addHandler(lh)

username = ''
if len(sys.argv) > 1:
    hostname = sys.argv[1]
    if hostname.find('@') >= 0:
        username, hostname = hostname.split('@')
else:
    hostname = raw_input('Hostname: ')
if len(hostname) == 0:
    print '*** Hostname required.'
    sys.exit(1)
port = 22
if hostname.find(':') >= 0:
    hostname, portstr = hostname.split(':')
    port = int(portstr)

# now connect
try:
    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    sock.connect((hostname, port))
except Exception, e:
    print '*** Connect failed: ' + str(e)
    traceback.print_exc()
    sys.exit(1)

try:
    event = threading.Event()
    t = paramiko.Transport(sock)
    t.start_client(event)
    # print repr(t)
    event.wait(15)
    if not t.is_active():
        print '*** SSH negotiation failed.'
        sys.exit(1)
    # print repr(t)

    keys = load_host_keys()
    keytype, hostkey = t.get_remote_server_key()
    if not keys.has_key(hostname):
        print '*** WARNING: Unknown host key!'
    elif not keys[hostname].has_key(keytype):
        print '*** WARNING: Unknown host key!'
    elif keys[hostname][keytype] != hostkey:
        print '*** WARNING: Host key has changed!!!'
        sys.exit(1)
    else:
        print '*** Host key OK.'

    event.clear()

    # get username
    if username == '':
        default_username = getpass.getuser()
        username = raw_input('Username [%s]: ' % default_username)
        if len(username) == 0:
            username = default_username

    # ask for what kind of authentication to try
    default_auth = 'p'
    auth = raw_input('Auth by (p)assword, (r)sa key, or (d)ss key? [%s] ' % default_auth)
    if len(auth) == 0:
        auth = default_auth

    if auth == 'r':
        key = paramiko.RSAKey()
        default_path = os.environ['HOME'] + '/.ssh/id_rsa'
        path = raw_input('RSA key [%s]: ' % default_path)
        if len(path) == 0:
            path = default_path
        key.read_private_key_file(path)
        t.auth_key(username, key, event)
    elif auth == 'd':
        key = paramiko.DSSKey()
        default_path = os.environ['HOME'] + '/.ssh/id_dsa'
        path = raw_input('DSS key [%s]: ' % default_path)
        if len(path) == 0:
            path = default_path
        key.read_private_key_file(path)
        t.auth_key(username, key, event)
    else:
        pw = getpass.getpass('Password for %s@%s: ' % (username, hostname))
        t.auth_password(username, pw, event)

    event.wait(10)
    # print repr(t)
    if not t.is_authenticated():
        print '*** Authentication failed. :('
        t.close()
        sys.exit(1)

    chan = t.open_session()
    chan.get_pty()
    chan.invoke_shell()
    print '*** Here we go!'
    print

    try:
        oldtty = termios.tcgetattr(sys.stdin)
        tty.setraw(sys.stdin.fileno())
        tty.setcbreak(sys.stdin.fileno())
        chan.settimeout(0.0)

        while 1:
            r, w, e = select.select([chan, sys.stdin], [], [])
            if chan in r:
                try:
                    x = chan.recv(1024)
                    if len(x) == 0:
                        print
                        print '*** EOF\r\n',
                        break
                    sys.stdout.write(x)
                    sys.stdout.flush()
                except socket.timeout:
                    pass
            if sys.stdin in r:
                # FIXME: reading 1 byte at a time is incredibly dumb.
                x = sys.stdin.read(1)
                if len(x) == 0:
                    print
                    print '*** Bye.\r\n',
                    break
                chan.send(x)

    finally:
        termios.tcsetattr(sys.stdin, termios.TCSADRAIN, oldtty)

    chan.close()
    t.close()

except Exception, e:
    print '*** Caught exception: ' + str(e.__class__) + ': ' + str(e)
    traceback.print_exc()
    try:
        t.close()
    except:
        pass
    sys.exit(1)