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7 """Class representing a TLS session."""
8
9 from .utils.compat import *
10 from .mathtls import *
11 from .constants import *
12
14 """
15 This class represents a TLS session.
16
17 TLS distinguishes between connections and sessions. A new
18 handshake creates both a connection and a session. Data is
19 transmitted over the connection.
20
21 The session contains a more permanent record of the handshake. The
22 session can be inspected to determine handshake results. The
23 session can also be used to create a new connection through
24 "session resumption". If the client and server both support this,
25 they can create a new connection based on an old session without
26 the overhead of a full handshake.
27
28 The session for a L{tlslite.TLSConnection.TLSConnection} can be
29 retrieved from the connection's 'session' attribute.
30
31 @type srpUsername: str
32 @ivar srpUsername: The client's SRP username (or None).
33
34 @type clientCertChain: L{tlslite.x509certchain.X509CertChain}
35 @ivar clientCertChain: The client's certificate chain (or None).
36
37 @type serverCertChain: L{tlslite.x509certchain.X509CertChain}
38 @ivar serverCertChain: The server's certificate chain (or None).
39
40 @type tackExt: L{tack.structures.TackExtension.TackExtension}
41 @ivar tackExt: The server's TackExtension (or None).
42
43 @type tackInHelloExt: L{bool}
44 @ivar tackInHelloExt:True if a TACK was presented via TLS Extension.
45
46 @type encryptThenMAC: bool
47 @ivar encryptThenMAC: True if connection uses CBC cipher in
48 encrypt-then-MAC mode
49 """
50
52 self.masterSecret = bytearray(0)
53 self.sessionID = bytearray(0)
54 self.cipherSuite = 0
55 self.srpUsername = ""
56 self.clientCertChain = None
57 self.serverCertChain = None
58 self.tackExt = None
59 self.tackInHelloExt = False
60 self.serverName = ""
61 self.resumable = False
62 self.encryptThenMAC = False
63
64 - def create(self, masterSecret, sessionID, cipherSuite,
65 srpUsername, clientCertChain, serverCertChain,
66 tackExt, tackInHelloExt, serverName, resumable=True,
67 encryptThenMAC=False):
68 self.masterSecret = masterSecret
69 self.sessionID = sessionID
70 self.cipherSuite = cipherSuite
71 self.srpUsername = srpUsername
72 self.clientCertChain = clientCertChain
73 self.serverCertChain = serverCertChain
74 self.tackExt = tackExt
75 self.tackInHelloExt = tackInHelloExt
76 self.serverName = serverName
77 self.resumable = resumable
78 self.encryptThenMAC = encryptThenMAC
79
81 other = Session()
82 other.masterSecret = self.masterSecret
83 other.sessionID = self.sessionID
84 other.cipherSuite = self.cipherSuite
85 other.srpUsername = self.srpUsername
86 other.clientCertChain = self.clientCertChain
87 other.serverCertChain = self.serverCertChain
88 other.tackExt = self.tackExt
89 other.tackInHelloExt = self.tackInHelloExt
90 other.serverName = self.serverName
91 other.resumable = self.resumable
92 other.encryptThenMAC = self.encryptThenMAC
93 return other
94
96 """If this session can be used for session resumption.
97
98 @rtype: bool
99 @return: If this session can be used for session resumption.
100 """
101 return self.resumable and self.sessionID
102
104
105 if (not boolean) or (boolean and self.sessionID):
106 self.resumable = boolean
107
113
115 if self.tackExt and self.tackExt.break_sigs:
116 return self.tackExt.break_sigs
117 else:
118 return None
119
121 """Get the name of the cipher used with this connection.
122
123 @rtype: str
124 @return: The name of the cipher used with this connection.
125 """
126 return CipherSuite.canonicalCipherName(self.cipherSuite)
127
129 """Get the name of the HMAC hash algo used with this connection.
130
131 @rtype: str
132 @return: The name of the HMAC hash algo used with this connection.
133 """
134 return CipherSuite.canonicalMacName(self.cipherSuite)
135