blob: e0b9ccc08aca14bb6469237fb49fc7daa2e61e61 (
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
|
package middleware
import (
"net/http"
"strings"
)
// AllowContentEncoding enforces a whitelist of request Content-Encoding otherwise responds
// with a 415 Unsupported Media Type status.
func AllowContentEncoding(contentEncoding ...string) func(next http.Handler) http.Handler {
allowedEncodings := make(map[string]struct{}, len(contentEncoding))
for _, encoding := range contentEncoding {
allowedEncodings[strings.TrimSpace(strings.ToLower(encoding))] = struct{}{}
}
return func(next http.Handler) http.Handler {
fn := func(w http.ResponseWriter, r *http.Request) {
requestEncodings := r.Header["Content-Encoding"]
// skip check for empty content body or no Content-Encoding
if r.ContentLength == 0 {
next.ServeHTTP(w, r)
return
}
// All encodings in the request must be allowed
for _, encoding := range requestEncodings {
if _, ok := allowedEncodings[strings.TrimSpace(strings.ToLower(encoding))]; !ok {
w.WriteHeader(http.StatusUnsupportedMediaType)
return
}
}
next.ServeHTTP(w, r)
}
return http.HandlerFunc(fn)
}
}
|
