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author | Tamal Saha <tamal@appscode.com> | 2019-08-23 09:40:30 -0700 |
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committer | techknowlogick <techknowlogick@gitea.io> | 2019-08-23 12:40:29 -0400 |
commit | 171b3598778a1ecd0a921c71ed6755bfef68f7f0 (patch) | |
tree | 02857629ef9e8e26ee0ee559153f803f77b588b7 /vendor/gitea.com/macaron/csrf/xsrf.go | |
parent | ca6fb004ac50fc924861112403895d637c6a2d1d (diff) | |
download | gitea-171b3598778a1ecd0a921c71ed6755bfef68f7f0.tar.gz gitea-171b3598778a1ecd0a921c71ed6755bfef68f7f0.zip |
Use gitea forked macaron (#7933)
Signed-off-by: Tamal Saha <tamal@appscode.com>
Diffstat (limited to 'vendor/gitea.com/macaron/csrf/xsrf.go')
-rw-r--r-- | vendor/gitea.com/macaron/csrf/xsrf.go | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/vendor/gitea.com/macaron/csrf/xsrf.go b/vendor/gitea.com/macaron/csrf/xsrf.go new file mode 100644 index 0000000000..7f31894f95 --- /dev/null +++ b/vendor/gitea.com/macaron/csrf/xsrf.go @@ -0,0 +1,97 @@ +// Copyright 2012 Google Inc. All Rights Reserved. +// Copyright 2014 The Macaron Authors +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package csrf + +import ( + "bytes" + "crypto/hmac" + "crypto/sha1" + "crypto/subtle" + "encoding/base64" + "fmt" + "strconv" + "strings" + "time" +) + +// The duration that XSRF tokens are valid. +// It is exported so clients may set cookie timeouts that match generated tokens. +const TIMEOUT = 24 * time.Hour + +// clean sanitizes a string for inclusion in a token by replacing all ":"s. +func clean(s string) string { + return strings.Replace(s, ":", "_", -1) +} + +// GenerateToken returns a URL-safe secure XSRF token that expires in 24 hours. +// +// key is a secret key for your application. +// userID is a unique identifier for the user. +// actionID is the action the user is taking (e.g. POSTing to a particular path). +func GenerateToken(key, userID, actionID string) string { + return generateTokenAtTime(key, userID, actionID, time.Now()) +} + +// generateTokenAtTime is like Generate, but returns a token that expires 24 hours from now. +func generateTokenAtTime(key, userID, actionID string, now time.Time) string { + h := hmac.New(sha1.New, []byte(key)) + fmt.Fprintf(h, "%s:%s:%d", clean(userID), clean(actionID), now.UnixNano()) + tok := fmt.Sprintf("%s:%d", h.Sum(nil), now.UnixNano()) + return base64.RawURLEncoding.EncodeToString([]byte(tok)) +} + +// Valid returns true if token is a valid, unexpired token returned by Generate. +func ValidToken(token, key, userID, actionID string) bool { + return validTokenAtTime(token, key, userID, actionID, time.Now()) +} + +// validTokenAtTime is like Valid, but it uses now to check if the token is expired. +func validTokenAtTime(token, key, userID, actionID string, now time.Time) bool { + // Decode the token. + data, err := base64.RawURLEncoding.DecodeString(token) + if err != nil { + return false + } + + // Extract the issue time of the token. + sep := bytes.LastIndex(data, []byte{':'}) + if sep < 0 { + return false + } + nanos, err := strconv.ParseInt(string(data[sep+1:]), 10, 64) + if err != nil { + return false + } + issueTime := time.Unix(0, nanos) + + // Check that the token is not expired. + if now.Sub(issueTime) >= TIMEOUT { + return false + } + + // Check that the token is not from the future. + // Allow 1 minute grace period in case the token is being verified on a + // machine whose clock is behind the machine that issued the token. + if issueTime.After(now.Add(1 * time.Minute)) { + return false + } + + expected := generateTokenAtTime(key, userID, actionID, issueTime) + + // Check that the token matches the expected value. + // Use constant time comparison to avoid timing attacks. + return subtle.ConstantTimeCompare([]byte(token), []byte(expected)) == 1 +} |