pgweb/vendor/github.com/gin-gonic/gin/auth.go
2017-01-20 13:21:18 -06:00

93 lines
2.8 KiB
Go

// Copyright 2014 Manu Martinez-Almeida. All rights reserved.
// Use of this source code is governed by a MIT style
// license that can be found in the LICENSE file.
package gin
import (
"crypto/subtle"
"encoding/base64"
"strconv"
)
const AuthUserKey = "user"
type (
Accounts map[string]string
authPair struct {
Value string
User string
}
authPairs []authPair
)
func (a authPairs) searchCredential(authValue string) (string, bool) {
if len(authValue) == 0 {
return "", false
}
for _, pair := range a {
if pair.Value == authValue {
return pair.User, true
}
}
return "", false
}
// BasicAuthForRealm returns a Basic HTTP Authorization middleware. It takes as arguments a map[string]string where
// the key is the user name and the value is the password, as well as the name of the Realm.
// If the realm is empty, "Authorization Required" will be used by default.
// (see http://tools.ietf.org/html/rfc2617#section-1.2)
func BasicAuthForRealm(accounts Accounts, realm string) HandlerFunc {
if realm == "" {
realm = "Authorization Required"
}
realm = "Basic realm=" + strconv.Quote(realm)
pairs := processAccounts(accounts)
return func(c *Context) {
// Search user in the slice of allowed credentials
user, found := pairs.searchCredential(c.Request.Header.Get("Authorization"))
if !found {
// Credentials doesn't match, we return 401 and abort handlers chain.
c.Header("WWW-Authenticate", realm)
c.AbortWithStatus(401)
} else {
// The user credentials was found, set user's id to key AuthUserKey in this context, the userId can be read later using
// c.MustGet(gin.AuthUserKey)
c.Set(AuthUserKey, user)
}
}
}
// BasicAuth returns a Basic HTTP Authorization middleware. It takes as argument a map[string]string where
// the key is the user name and the value is the password.
func BasicAuth(accounts Accounts) HandlerFunc {
return BasicAuthForRealm(accounts, "")
}
func processAccounts(accounts Accounts) authPairs {
assert1(len(accounts) > 0, "Empty list of authorized credentials")
pairs := make(authPairs, 0, len(accounts))
for user, password := range accounts {
assert1(len(user) > 0, "User can not be empty")
value := authorizationHeader(user, password)
pairs = append(pairs, authPair{
Value: value,
User: user,
})
}
return pairs
}
func authorizationHeader(user, password string) string {
base := user + ":" + password
return "Basic " + base64.StdEncoding.EncodeToString([]byte(base))
}
func secureCompare(given, actual string) bool {
if subtle.ConstantTimeEq(int32(len(given)), int32(len(actual))) == 1 {
return subtle.ConstantTimeCompare([]byte(given), []byte(actual)) == 1
}
/* Securely compare actual to itself to keep constant time, but always return false */
return subtle.ConstantTimeCompare([]byte(actual), []byte(actual)) == 1 && false
}