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
180
181
182
183
|
// Copyright 2012 The Go-MySQL-Driver Authors. All rights reserved.
//
// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this file,
// You can obtain one at http://mozilla.org/MPL/2.0/.
// Package mysql provides a MySQL driver for Go's database/sql package
//
// The driver should be used via the database/sql package:
//
// import "database/sql"
// import _ "github.com/go-sql-driver/mysql"
//
// db, err := sql.Open("mysql", "user:password@/dbname")
//
// See https://github.com/go-sql-driver/mysql#usage for details
package mysql
import (
"database/sql"
"database/sql/driver"
"net"
)
// MySQLDriver is exported to make the driver directly accessible.
// In general the driver is used via the database/sql package.
type MySQLDriver struct{}
// DialFunc is a function which can be used to establish the network connection.
// Custom dial functions must be registered with RegisterDial
type DialFunc func(addr string) (net.Conn, error)
var dials map[string]DialFunc
// RegisterDial registers a custom dial function. It can then be used by the
// network address mynet(addr), where mynet is the registered new network.
// addr is passed as a parameter to the dial function.
func RegisterDial(net string, dial DialFunc) {
if dials == nil {
dials = make(map[string]DialFunc)
}
dials[net] = dial
}
// Open new Connection.
// See https://github.com/go-sql-driver/mysql#dsn-data-source-name for how
// the DSN string is formated
func (d MySQLDriver) Open(dsn string) (driver.Conn, error) {
var err error
// New mysqlConn
mc := &mysqlConn{
maxAllowedPacket: maxPacketSize,
maxWriteSize: maxPacketSize - 1,
}
mc.cfg, err = ParseDSN(dsn)
if err != nil {
return nil, err
}
mc.parseTime = mc.cfg.ParseTime
mc.strict = mc.cfg.Strict
// Connect to Server
if dial, ok := dials[mc.cfg.Net]; ok {
mc.netConn, err = dial(mc.cfg.Addr)
} else {
nd := net.Dialer{Timeout: mc.cfg.Timeout}
mc.netConn, err = nd.Dial(mc.cfg.Net, mc.cfg.Addr)
}
if err != nil {
return nil, err
}
// Enable TCP Keepalives on TCP connections
if tc, ok := mc.netConn.(*net.TCPConn); ok {
if err := tc.SetKeepAlive(true); err != nil {
// Don't send COM_QUIT before handshake.
mc.netConn.Close()
mc.netConn = nil
return nil, err
}
}
mc.buf = newBuffer(mc.netConn)
// Set I/O timeouts
mc.buf.timeout = mc.cfg.ReadTimeout
mc.writeTimeout = mc.cfg.WriteTimeout
// Reading Handshake Initialization Packet
cipher, err := mc.readInitPacket()
if err != nil {
mc.cleanup()
return nil, err
}
// Send Client Authentication Packet
if err = mc.writeAuthPacket(cipher); err != nil {
mc.cleanup()
return nil, err
}
// Handle response to auth packet, switch methods if possible
if err = handleAuthResult(mc, cipher); err != nil {
// Authentication failed and MySQL has already closed the connection
// (https://dev.mysql.com/doc/internals/en/authentication-fails.html).
// Do not send COM_QUIT, just cleanup and return the error.
mc.cleanup()
return nil, err
}
if mc.cfg.MaxAllowedPacket > 0 {
mc.maxAllowedPacket = mc.cfg.MaxAllowedPacket
} else {
// Get max allowed packet size
maxap, err := mc.getSystemVar("max_allowed_packet")
if err != nil {
mc.Close()
return nil, err
}
mc.maxAllowedPacket = stringToInt(maxap) - 1
}
if mc.maxAllowedPacket < maxPacketSize {
mc.maxWriteSize = mc.maxAllowedPacket
}
// Handle DSN Params
err = mc.handleParams()
if err != nil {
mc.Close()
return nil, err
}
return mc, nil
}
func handleAuthResult(mc *mysqlConn, oldCipher []byte) error {
// Read Result Packet
cipher, err := mc.readResultOK()
if err == nil {
return nil // auth successful
}
if mc.cfg == nil {
return err // auth failed and retry not possible
}
// Retry auth if configured to do so.
if mc.cfg.AllowOldPasswords && err == ErrOldPassword {
// Retry with old authentication method. Note: there are edge cases
// where this should work but doesn't; this is currently "wontfix":
// https://github.com/go-sql-driver/mysql/issues/184
// If CLIENT_PLUGIN_AUTH capability is not supported, no new cipher is
// sent and we have to keep using the cipher sent in the init packet.
if cipher == nil {
cipher = oldCipher
}
if err = mc.writeOldAuthPacket(cipher); err != nil {
return err
}
_, err = mc.readResultOK()
} else if mc.cfg.AllowCleartextPasswords && err == ErrCleartextPassword {
// Retry with clear text password for
// http://dev.mysql.com/doc/refman/5.7/en/cleartext-authentication-plugin.html
// http://dev.mysql.com/doc/refman/5.7/en/pam-authentication-plugin.html
if err = mc.writeClearAuthPacket(); err != nil {
return err
}
_, err = mc.readResultOK()
} else if mc.cfg.AllowNativePasswords && err == ErrNativePassword {
if err = mc.writeNativeAuthPacket(cipher); err != nil {
return err
}
_, err = mc.readResultOK()
}
return err
}
func init() {
sql.Register("mysql", &MySQLDriver{})
}
|
