From 8c12c6939aab9106db14ec2d11d983bc5b29fb2c Mon Sep 17 00:00:00 2001 From: Niall Sheridan Date: Sun, 7 Jul 2019 21:33:44 +0100 Subject: Switch to modules --- .../gorilla/securecookie/securecookie.go | 646 --------------------- 1 file changed, 646 deletions(-) delete mode 100644 vendor/github.com/gorilla/securecookie/securecookie.go (limited to 'vendor/github.com/gorilla/securecookie/securecookie.go') diff --git a/vendor/github.com/gorilla/securecookie/securecookie.go b/vendor/github.com/gorilla/securecookie/securecookie.go deleted file mode 100644 index 61af390..0000000 --- a/vendor/github.com/gorilla/securecookie/securecookie.go +++ /dev/null @@ -1,646 +0,0 @@ -// Copyright 2012 The Gorilla Authors. All rights reserved. -// Use of this source code is governed by a BSD-style -// license that can be found in the LICENSE file. - -package securecookie - -import ( - "bytes" - "crypto/aes" - "crypto/cipher" - "crypto/hmac" - "crypto/rand" - "crypto/sha256" - "crypto/subtle" - "encoding/base64" - "encoding/gob" - "encoding/json" - "fmt" - "hash" - "io" - "strconv" - "strings" - "time" -) - -// Error is the interface of all errors returned by functions in this library. -type Error interface { - error - - // IsUsage returns true for errors indicating the client code probably - // uses this library incorrectly. For example, the client may have - // failed to provide a valid hash key, or may have failed to configure - // the Serializer adequately for encoding value. - IsUsage() bool - - // IsDecode returns true for errors indicating that a cookie could not - // be decoded and validated. Since cookies are usually untrusted - // user-provided input, errors of this type should be expected. - // Usually, the proper action is simply to reject the request. - IsDecode() bool - - // IsInternal returns true for unexpected errors occurring in the - // securecookie implementation. - IsInternal() bool - - // Cause, if it returns a non-nil value, indicates that this error was - // propagated from some underlying library. If this method returns nil, - // this error was raised directly by this library. - // - // Cause is provided principally for debugging/logging purposes; it is - // rare that application logic should perform meaningfully different - // logic based on Cause. See, for example, the caveats described on - // (MultiError).Cause(). - Cause() error -} - -// errorType is a bitmask giving the error type(s) of an cookieError value. -type errorType int - -const ( - usageError = errorType(1 << iota) - decodeError - internalError -) - -type cookieError struct { - typ errorType - msg string - cause error -} - -func (e cookieError) IsUsage() bool { return (e.typ & usageError) != 0 } -func (e cookieError) IsDecode() bool { return (e.typ & decodeError) != 0 } -func (e cookieError) IsInternal() bool { return (e.typ & internalError) != 0 } - -func (e cookieError) Cause() error { return e.cause } - -func (e cookieError) Error() string { - parts := []string{"securecookie: "} - if e.msg == "" { - parts = append(parts, "error") - } else { - parts = append(parts, e.msg) - } - if c := e.Cause(); c != nil { - parts = append(parts, " - caused by: ", c.Error()) - } - return strings.Join(parts, "") -} - -var ( - errGeneratingIV = cookieError{typ: internalError, msg: "failed to generate random iv"} - - errNoCodecs = cookieError{typ: usageError, msg: "no codecs provided"} - errHashKeyNotSet = cookieError{typ: usageError, msg: "hash key is not set"} - errBlockKeyNotSet = cookieError{typ: usageError, msg: "block key is not set"} - errEncodedValueTooLong = cookieError{typ: usageError, msg: "the value is too long"} - - errValueToDecodeTooLong = cookieError{typ: decodeError, msg: "the value is too long"} - errTimestampInvalid = cookieError{typ: decodeError, msg: "invalid timestamp"} - errTimestampTooNew = cookieError{typ: decodeError, msg: "timestamp is too new"} - errTimestampExpired = cookieError{typ: decodeError, msg: "expired timestamp"} - errDecryptionFailed = cookieError{typ: decodeError, msg: "the value could not be decrypted"} - errValueNotByte = cookieError{typ: decodeError, msg: "value not a []byte."} - errValueNotBytePtr = cookieError{typ: decodeError, msg: "value not a pointer to []byte."} - - // ErrMacInvalid indicates that cookie decoding failed because the HMAC - // could not be extracted and verified. Direct use of this error - // variable is deprecated; it is public only for legacy compatibility, - // and may be privatized in the future, as it is rarely useful to - // distinguish between this error and other Error implementations. - ErrMacInvalid = cookieError{typ: decodeError, msg: "the value is not valid"} -) - -// Codec defines an interface to encode and decode cookie values. -type Codec interface { - Encode(name string, value interface{}) (string, error) - Decode(name, value string, dst interface{}) error -} - -// New returns a new SecureCookie. -// -// hashKey is required, used to authenticate values using HMAC. Create it using -// GenerateRandomKey(). It is recommended to use a key with 32 or 64 bytes. -// -// blockKey is optional, used to encrypt values. Create it using -// GenerateRandomKey(). The key length must correspond to the block size -// of the encryption algorithm. For AES, used by default, valid lengths are -// 16, 24, or 32 bytes to select AES-128, AES-192, or AES-256. -// The default encoder used for cookie serialization is encoding/gob. -// -// Note that keys created using GenerateRandomKey() are not automatically -// persisted. New keys will be created when the application is restarted, and -// previously issued cookies will not be able to be decoded. -func New(hashKey, blockKey []byte) *SecureCookie { - s := &SecureCookie{ - hashKey: hashKey, - blockKey: blockKey, - hashFunc: sha256.New, - maxAge: 86400 * 30, - maxLength: 4096, - sz: GobEncoder{}, - } - if len(hashKey) == 0 { - s.err = errHashKeyNotSet - } - if blockKey != nil { - s.BlockFunc(aes.NewCipher) - } - return s -} - -// SecureCookie encodes and decodes authenticated and optionally encrypted -// cookie values. -type SecureCookie struct { - hashKey []byte - hashFunc func() hash.Hash - blockKey []byte - block cipher.Block - maxLength int - maxAge int64 - minAge int64 - err error - sz Serializer - // For testing purposes, the function that returns the current timestamp. - // If not set, it will use time.Now().UTC().Unix(). - timeFunc func() int64 -} - -// Serializer provides an interface for providing custom serializers for cookie -// values. -type Serializer interface { - Serialize(src interface{}) ([]byte, error) - Deserialize(src []byte, dst interface{}) error -} - -// GobEncoder encodes cookie values using encoding/gob. This is the simplest -// encoder and can handle complex types via gob.Register. -type GobEncoder struct{} - -// JSONEncoder encodes cookie values using encoding/json. Users who wish to -// encode complex types need to satisfy the json.Marshaller and -// json.Unmarshaller interfaces. -type JSONEncoder struct{} - -// NopEncoder does not encode cookie values, and instead simply accepts a []byte -// (as an interface{}) and returns a []byte. This is particularly useful when -// you encoding an object upstream and do not wish to re-encode it. -type NopEncoder struct{} - -// MaxLength restricts the maximum length, in bytes, for the cookie value. -// -// Default is 4096, which is the maximum value accepted by Internet Explorer. -func (s *SecureCookie) MaxLength(value int) *SecureCookie { - s.maxLength = value - return s -} - -// MaxAge restricts the maximum age, in seconds, for the cookie value. -// -// Default is 86400 * 30. Set it to 0 for no restriction. -func (s *SecureCookie) MaxAge(value int) *SecureCookie { - s.maxAge = int64(value) - return s -} - -// MinAge restricts the minimum age, in seconds, for the cookie value. -// -// Default is 0 (no restriction). -func (s *SecureCookie) MinAge(value int) *SecureCookie { - s.minAge = int64(value) - return s -} - -// HashFunc sets the hash function used to create HMAC. -// -// Default is crypto/sha256.New. -func (s *SecureCookie) HashFunc(f func() hash.Hash) *SecureCookie { - s.hashFunc = f - return s -} - -// BlockFunc sets the encryption function used to create a cipher.Block. -// -// Default is crypto/aes.New. -func (s *SecureCookie) BlockFunc(f func([]byte) (cipher.Block, error)) *SecureCookie { - if s.blockKey == nil { - s.err = errBlockKeyNotSet - } else if block, err := f(s.blockKey); err == nil { - s.block = block - } else { - s.err = cookieError{cause: err, typ: usageError} - } - return s -} - -// Encoding sets the encoding/serialization method for cookies. -// -// Default is encoding/gob. To encode special structures using encoding/gob, -// they must be registered first using gob.Register(). -func (s *SecureCookie) SetSerializer(sz Serializer) *SecureCookie { - s.sz = sz - - return s -} - -// Encode encodes a cookie value. -// -// It serializes, optionally encrypts, signs with a message authentication code, -// and finally encodes the value. -// -// The name argument is the cookie name. It is stored with the encoded value. -// The value argument is the value to be encoded. It can be any value that can -// be encoded using the currently selected serializer; see SetSerializer(). -// -// It is the client's responsibility to ensure that value, when encoded using -// the current serialization/encryption settings on s and then base64-encoded, -// is shorter than the maximum permissible length. -func (s *SecureCookie) Encode(name string, value interface{}) (string, error) { - if s.err != nil { - return "", s.err - } - if s.hashKey == nil { - s.err = errHashKeyNotSet - return "", s.err - } - var err error - var b []byte - // 1. Serialize. - if b, err = s.sz.Serialize(value); err != nil { - return "", cookieError{cause: err, typ: usageError} - } - // 2. Encrypt (optional). - if s.block != nil { - if b, err = encrypt(s.block, b); err != nil { - return "", cookieError{cause: err, typ: usageError} - } - } - b = encode(b) - // 3. Create MAC for "name|date|value". Extra pipe to be used later. - b = []byte(fmt.Sprintf("%s|%d|%s|", name, s.timestamp(), b)) - mac := createMac(hmac.New(s.hashFunc, s.hashKey), b[:len(b)-1]) - // Append mac, remove name. - b = append(b, mac...)[len(name)+1:] - // 4. Encode to base64. - b = encode(b) - // 5. Check length. - if s.maxLength != 0 && len(b) > s.maxLength { - return "", errEncodedValueTooLong - } - // Done. - return string(b), nil -} - -// Decode decodes a cookie value. -// -// It decodes, verifies a message authentication code, optionally decrypts and -// finally deserializes the value. -// -// The name argument is the cookie name. It must be the same name used when -// it was stored. The value argument is the encoded cookie value. The dst -// argument is where the cookie will be decoded. It must be a pointer. -func (s *SecureCookie) Decode(name, value string, dst interface{}) error { - if s.err != nil { - return s.err - } - if s.hashKey == nil { - s.err = errHashKeyNotSet - return s.err - } - // 1. Check length. - if s.maxLength != 0 && len(value) > s.maxLength { - return errValueToDecodeTooLong - } - // 2. Decode from base64. - b, err := decode([]byte(value)) - if err != nil { - return err - } - // 3. Verify MAC. Value is "date|value|mac". - parts := bytes.SplitN(b, []byte("|"), 3) - if len(parts) != 3 { - return ErrMacInvalid - } - h := hmac.New(s.hashFunc, s.hashKey) - b = append([]byte(name+"|"), b[:len(b)-len(parts[2])-1]...) - if err = verifyMac(h, b, parts[2]); err != nil { - return err - } - // 4. Verify date ranges. - var t1 int64 - if t1, err = strconv.ParseInt(string(parts[0]), 10, 64); err != nil { - return errTimestampInvalid - } - t2 := s.timestamp() - if s.minAge != 0 && t1 > t2-s.minAge { - return errTimestampTooNew - } - if s.maxAge != 0 && t1 < t2-s.maxAge { - return errTimestampExpired - } - // 5. Decrypt (optional). - b, err = decode(parts[1]) - if err != nil { - return err - } - if s.block != nil { - if b, err = decrypt(s.block, b); err != nil { - return err - } - } - // 6. Deserialize. - if err = s.sz.Deserialize(b, dst); err != nil { - return cookieError{cause: err, typ: decodeError} - } - // Done. - return nil -} - -// timestamp returns the current timestamp, in seconds. -// -// For testing purposes, the function that generates the timestamp can be -// overridden. If not set, it will return time.Now().UTC().Unix(). -func (s *SecureCookie) timestamp() int64 { - if s.timeFunc == nil { - return time.Now().UTC().Unix() - } - return s.timeFunc() -} - -// Authentication ------------------------------------------------------------- - -// createMac creates a message authentication code (MAC). -func createMac(h hash.Hash, value []byte) []byte { - h.Write(value) - return h.Sum(nil) -} - -// verifyMac verifies that a message authentication code (MAC) is valid. -func verifyMac(h hash.Hash, value []byte, mac []byte) error { - mac2 := createMac(h, value) - // Check that both MACs are of equal length, as subtle.ConstantTimeCompare - // does not do this prior to Go 1.4. - if len(mac) == len(mac2) && subtle.ConstantTimeCompare(mac, mac2) == 1 { - return nil - } - return ErrMacInvalid -} - -// Encryption ----------------------------------------------------------------- - -// encrypt encrypts a value using the given block in counter mode. -// -// A random initialization vector (http://goo.gl/zF67k) with the length of the -// block size is prepended to the resulting ciphertext. -func encrypt(block cipher.Block, value []byte) ([]byte, error) { - iv := GenerateRandomKey(block.BlockSize()) - if iv == nil { - return nil, errGeneratingIV - } - // Encrypt it. - stream := cipher.NewCTR(block, iv) - stream.XORKeyStream(value, value) - // Return iv + ciphertext. - return append(iv, value...), nil -} - -// decrypt decrypts a value using the given block in counter mode. -// -// The value to be decrypted must be prepended by a initialization vector -// (http://goo.gl/zF67k) with the length of the block size. -func decrypt(block cipher.Block, value []byte) ([]byte, error) { - size := block.BlockSize() - if len(value) > size { - // Extract iv. - iv := value[:size] - // Extract ciphertext. - value = value[size:] - // Decrypt it. - stream := cipher.NewCTR(block, iv) - stream.XORKeyStream(value, value) - return value, nil - } - return nil, errDecryptionFailed -} - -// Serialization -------------------------------------------------------------- - -// Serialize encodes a value using gob. -func (e GobEncoder) Serialize(src interface{}) ([]byte, error) { - buf := new(bytes.Buffer) - enc := gob.NewEncoder(buf) - if err := enc.Encode(src); err != nil { - return nil, cookieError{cause: err, typ: usageError} - } - return buf.Bytes(), nil -} - -// Deserialize decodes a value using gob. -func (e GobEncoder) Deserialize(src []byte, dst interface{}) error { - dec := gob.NewDecoder(bytes.NewBuffer(src)) - if err := dec.Decode(dst); err != nil { - return cookieError{cause: err, typ: decodeError} - } - return nil -} - -// Serialize encodes a value using encoding/json. -func (e JSONEncoder) Serialize(src interface{}) ([]byte, error) { - buf := new(bytes.Buffer) - enc := json.NewEncoder(buf) - if err := enc.Encode(src); err != nil { - return nil, cookieError{cause: err, typ: usageError} - } - return buf.Bytes(), nil -} - -// Deserialize decodes a value using encoding/json. -func (e JSONEncoder) Deserialize(src []byte, dst interface{}) error { - dec := json.NewDecoder(bytes.NewReader(src)) - if err := dec.Decode(dst); err != nil { - return cookieError{cause: err, typ: decodeError} - } - return nil -} - -// Serialize passes a []byte through as-is. -func (e NopEncoder) Serialize(src interface{}) ([]byte, error) { - if b, ok := src.([]byte); ok { - return b, nil - } - - return nil, errValueNotByte -} - -// Deserialize passes a []byte through as-is. -func (e NopEncoder) Deserialize(src []byte, dst interface{}) error { - if dat, ok := dst.(*[]byte); ok { - *dat = src - return nil - } - return errValueNotBytePtr -} - -// Encoding ------------------------------------------------------------------- - -// encode encodes a value using base64. -func encode(value []byte) []byte { - encoded := make([]byte, base64.URLEncoding.EncodedLen(len(value))) - base64.URLEncoding.Encode(encoded, value) - return encoded -} - -// decode decodes a cookie using base64. -func decode(value []byte) ([]byte, error) { - decoded := make([]byte, base64.URLEncoding.DecodedLen(len(value))) - b, err := base64.URLEncoding.Decode(decoded, value) - if err != nil { - return nil, cookieError{cause: err, typ: decodeError, msg: "base64 decode failed"} - } - return decoded[:b], nil -} - -// Helpers -------------------------------------------------------------------- - -// GenerateRandomKey creates a random key with the given length in bytes. -// On failure, returns nil. -// -// Callers should explicitly check for the possibility of a nil return, treat -// it as a failure of the system random number generator, and not continue. -func GenerateRandomKey(length int) []byte { - k := make([]byte, length) - if _, err := io.ReadFull(rand.Reader, k); err != nil { - return nil - } - return k -} - -// CodecsFromPairs returns a slice of SecureCookie instances. -// -// It is a convenience function to create a list of codecs for key rotation. Note -// that the generated Codecs will have the default options applied: callers -// should iterate over each Codec and type-assert the underlying *SecureCookie to -// change these. -// -// Example: -// -// codecs := securecookie.CodecsFromPairs( -// []byte("new-hash-key"), -// []byte("new-block-key"), -// []byte("old-hash-key"), -// []byte("old-block-key"), -// ) -// -// // Modify each instance. -// for _, s := range codecs { -// if cookie, ok := s.(*securecookie.SecureCookie); ok { -// cookie.MaxAge(86400 * 7) -// cookie.SetSerializer(securecookie.JSONEncoder{}) -// cookie.HashFunc(sha512.New512_256) -// } -// } -// -func CodecsFromPairs(keyPairs ...[]byte) []Codec { - codecs := make([]Codec, len(keyPairs)/2+len(keyPairs)%2) - for i := 0; i < len(keyPairs); i += 2 { - var blockKey []byte - if i+1 < len(keyPairs) { - blockKey = keyPairs[i+1] - } - codecs[i/2] = New(keyPairs[i], blockKey) - } - return codecs -} - -// EncodeMulti encodes a cookie value using a group of codecs. -// -// The codecs are tried in order. Multiple codecs are accepted to allow -// key rotation. -// -// On error, may return a MultiError. -func EncodeMulti(name string, value interface{}, codecs ...Codec) (string, error) { - if len(codecs) == 0 { - return "", errNoCodecs - } - - var errors MultiError - for _, codec := range codecs { - encoded, err := codec.Encode(name, value) - if err == nil { - return encoded, nil - } - errors = append(errors, err) - } - return "", errors -} - -// DecodeMulti decodes a cookie value using a group of codecs. -// -// The codecs are tried in order. Multiple codecs are accepted to allow -// key rotation. -// -// On error, may return a MultiError. -func DecodeMulti(name string, value string, dst interface{}, codecs ...Codec) error { - if len(codecs) == 0 { - return errNoCodecs - } - - var errors MultiError - for _, codec := range codecs { - err := codec.Decode(name, value, dst) - if err == nil { - return nil - } - errors = append(errors, err) - } - return errors -} - -// MultiError groups multiple errors. -type MultiError []error - -func (m MultiError) IsUsage() bool { return m.any(func(e Error) bool { return e.IsUsage() }) } -func (m MultiError) IsDecode() bool { return m.any(func(e Error) bool { return e.IsDecode() }) } -func (m MultiError) IsInternal() bool { return m.any(func(e Error) bool { return e.IsInternal() }) } - -// Cause returns nil for MultiError; there is no unique underlying cause in the -// general case. -// -// Note: we could conceivably return a non-nil Cause only when there is exactly -// one child error with a Cause. However, it would be brittle for client code -// to rely on the arity of causes inside a MultiError, so we have opted not to -// provide this functionality. Clients which really wish to access the Causes -// of the underlying errors are free to iterate through the errors themselves. -func (m MultiError) Cause() error { return nil } - -func (m MultiError) Error() string { - s, n := "", 0 - for _, e := range m { - if e != nil { - if n == 0 { - s = e.Error() - } - n++ - } - } - switch n { - case 0: - return "(0 errors)" - case 1: - return s - case 2: - return s + " (and 1 other error)" - } - return fmt.Sprintf("%s (and %d other errors)", s, n-1) -} - -// any returns true if any element of m is an Error for which pred returns true. -func (m MultiError) any(pred func(Error) bool) bool { - for _, e := range m { - if ourErr, ok := e.(Error); ok && pred(ourErr) { - return true - } - } - return false -} -- cgit v1.2.3