blob: 4188675b03b6643335d488f4954bdd0fa3ecf305 (
plain) (
blame)
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
|
package middleware
import (
"strings"
"github.com/labstack/echo/v4"
)
type (
// TrailingSlashConfig defines the config for TrailingSlash middleware.
TrailingSlashConfig struct {
// Skipper defines a function to skip middleware.
Skipper Skipper
// Status code to be used when redirecting the request.
// Optional, but when provided the request is redirected using this code.
RedirectCode int `yaml:"redirect_code"`
}
)
var (
// DefaultTrailingSlashConfig is the default TrailingSlash middleware config.
DefaultTrailingSlashConfig = TrailingSlashConfig{
Skipper: DefaultSkipper,
}
)
// AddTrailingSlash returns a root level (before router) middleware which adds a
// trailing slash to the request `URL#Path`.
//
// Usage `Echo#Pre(AddTrailingSlash())`
func AddTrailingSlash() echo.MiddlewareFunc {
return AddTrailingSlashWithConfig(DefaultTrailingSlashConfig)
}
// AddTrailingSlashWithConfig returns a AddTrailingSlash middleware with config.
// See `AddTrailingSlash()`.
func AddTrailingSlashWithConfig(config TrailingSlashConfig) echo.MiddlewareFunc {
// Defaults
if config.Skipper == nil {
config.Skipper = DefaultTrailingSlashConfig.Skipper
}
return func(next echo.HandlerFunc) echo.HandlerFunc {
return func(c echo.Context) error {
if config.Skipper(c) {
return next(c)
}
req := c.Request()
url := req.URL
path := url.Path
qs := c.QueryString()
if !strings.HasSuffix(path, "/") {
path += "/"
uri := path
if qs != "" {
uri += "?" + qs
}
// Redirect
if config.RedirectCode != 0 {
return c.Redirect(config.RedirectCode, sanitizeURI(uri))
}
// Forward
req.RequestURI = uri
url.Path = path
}
return next(c)
}
}
}
// RemoveTrailingSlash returns a root level (before router) middleware which removes
// a trailing slash from the request URI.
//
// Usage `Echo#Pre(RemoveTrailingSlash())`
func RemoveTrailingSlash() echo.MiddlewareFunc {
return RemoveTrailingSlashWithConfig(TrailingSlashConfig{})
}
// RemoveTrailingSlashWithConfig returns a RemoveTrailingSlash middleware with config.
// See `RemoveTrailingSlash()`.
func RemoveTrailingSlashWithConfig(config TrailingSlashConfig) echo.MiddlewareFunc {
// Defaults
if config.Skipper == nil {
config.Skipper = DefaultTrailingSlashConfig.Skipper
}
return func(next echo.HandlerFunc) echo.HandlerFunc {
return func(c echo.Context) error {
if config.Skipper(c) {
return next(c)
}
req := c.Request()
url := req.URL
path := url.Path
qs := c.QueryString()
l := len(path) - 1
if l > 0 && strings.HasSuffix(path, "/") {
path = path[:l]
uri := path
if qs != "" {
uri += "?" + qs
}
// Redirect
if config.RedirectCode != 0 {
return c.Redirect(config.RedirectCode, sanitizeURI(uri))
}
// Forward
req.RequestURI = uri
url.Path = path
}
return next(c)
}
}
}
func sanitizeURI(uri string) string {
// double slash `\\`, `//` or even `\/` is absolute uri for browsers and by redirecting request to that uri
// we are vulnerable to open redirect attack. so replace all slashes from the beginning with single slash
if len(uri) > 1 && (uri[0] == '\\' || uri[0] == '/') && (uri[1] == '\\' || uri[1] == '/') {
uri = "/" + strings.TrimLeft(uri, `/\`)
}
return uri
}
|
