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author | Christopher Speller <crspeller@gmail.com> | 2016-05-12 15:08:58 -0400 |
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committer | Christopher Speller <crspeller@gmail.com> | 2016-05-12 16:37:29 -0400 |
commit | 84d2482ddbff9564c9ad75b2d30af66e3ddfd44d (patch) | |
tree | 8bfa567d2b6381f4a996ada2deff8a16aa85a3ac /Godeps/_workspace/src/github.com/dgryski/dgoogauth/googauth.go | |
parent | d1efb66ad7b017f0fbfe6f0c20843b30f396e504 (diff) | |
download | chat-84d2482ddbff9564c9ad75b2d30af66e3ddfd44d.tar.gz chat-84d2482ddbff9564c9ad75b2d30af66e3ddfd44d.tar.bz2 chat-84d2482ddbff9564c9ad75b2d30af66e3ddfd44d.zip |
Updating go depencancies. Switching to go1.6 vendoring (#2949)
Diffstat (limited to 'Godeps/_workspace/src/github.com/dgryski/dgoogauth/googauth.go')
-rw-r--r-- | Godeps/_workspace/src/github.com/dgryski/dgoogauth/googauth.go | 199 |
1 files changed, 0 insertions, 199 deletions
diff --git a/Godeps/_workspace/src/github.com/dgryski/dgoogauth/googauth.go b/Godeps/_workspace/src/github.com/dgryski/dgoogauth/googauth.go deleted file mode 100644 index 1efddcc20..000000000 --- a/Godeps/_workspace/src/github.com/dgryski/dgoogauth/googauth.go +++ /dev/null @@ -1,199 +0,0 @@ -/* -Package dgoogauth implements the one-time password algorithms supported by Google Authenticator - -This package supports the HMAC-Based One-time Password (HOTP) algorithm -specified in RFC 4226 and the Time-based One-time Password (TOTP) algorithm -specified in RFC 6238. -*/ -package dgoogauth - -import ( - "crypto/hmac" - "crypto/sha1" - "encoding/base32" - "encoding/binary" - "errors" - "net/url" - "sort" - "strconv" - "time" -) - -// Much of this code assumes int == int64, which probably is not the case. - -// ComputeCode computes the response code for a 64-bit challenge 'value' using the secret 'secret'. -// To avoid breaking compatibility with the previous API, it returns an invalid code (-1) when an error occurs, -// but does not silently ignore them (it forces a mismatch so the code will be rejected). -func ComputeCode(secret string, value int64) int { - - key, err := base32.StdEncoding.DecodeString(secret) - if err != nil { - return -1 - } - - hash := hmac.New(sha1.New, key) - err = binary.Write(hash, binary.BigEndian, value) - if err != nil { - return -1 - } - h := hash.Sum(nil) - - offset := h[19] & 0x0f - - truncated := binary.BigEndian.Uint32(h[offset : offset+4]) - - truncated &= 0x7fffffff - code := truncated % 1000000 - - return int(code) -} - -// ErrInvalidCode indicate the supplied one-time code was not valid -var ErrInvalidCode = errors.New("invalid code") - -// OTPConfig is a one-time-password configuration. This object will be modified by calls to -// Authenticate and should be saved to ensure the codes are in fact only used -// once. -type OTPConfig struct { - Secret string // 80-bit base32 encoded string of the user's secret - WindowSize int // valid range: technically 0..100 or so, but beyond 3-5 is probably bad security - HotpCounter int // the current otp counter. 0 if the user uses time-based codes instead. - DisallowReuse []int // timestamps in the current window unavailable for re-use - ScratchCodes []int // an array of 8-digit numeric codes that can be used to log in - UTC bool // use UTC for the timestamp instead of local time -} - -func (c *OTPConfig) checkScratchCodes(code int) bool { - - for i, v := range c.ScratchCodes { - if code == v { - // remove this code from the list of valid ones - l := len(c.ScratchCodes) - 1 - c.ScratchCodes[i] = c.ScratchCodes[l] // copy last element over this element - c.ScratchCodes = c.ScratchCodes[0:l] // and trim the list length by 1 - return true - } - } - - return false -} - -func (c *OTPConfig) checkHotpCode(code int) bool { - - for i := 0; i < c.WindowSize; i++ { - if ComputeCode(c.Secret, int64(c.HotpCounter+i)) == code { - c.HotpCounter += i + 1 - // We don't check for overflow here, which means you can only authenticate 2^63 times - // After that, the counter is negative and the above 'if' test will fail. - // This matches the behaviour of the PAM module. - return true - } - } - - // we must always advance the counter if we tried to authenticate with it - c.HotpCounter++ - return false -} - -func (c *OTPConfig) checkTotpCode(t0, code int) bool { - - minT := t0 - (c.WindowSize / 2) - maxT := t0 + (c.WindowSize / 2) - for t := minT; t <= maxT; t++ { - if ComputeCode(c.Secret, int64(t)) == code { - - if c.DisallowReuse != nil { - for _, timeCode := range c.DisallowReuse { - if timeCode == t { - return false - } - } - - // code hasn't been used before - c.DisallowReuse = append(c.DisallowReuse, t) - - // remove all time codes outside of the valid window - sort.Ints(c.DisallowReuse) - min := 0 - for c.DisallowReuse[min] < minT { - min++ - } - // FIXME: check we don't have an off-by-one error here - c.DisallowReuse = c.DisallowReuse[min:] - } - - return true - } - } - - return false -} - -// Authenticate a one-time-password against the given OTPConfig -// Returns true/false if the authentication was successful. -// Returns error if the password is incorrectly formatted (not a zero-padded 6 or non-zero-padded 8 digit number). -func (c *OTPConfig) Authenticate(password string) (bool, error) { - - var scratch bool - - switch { - case len(password) == 6 && password[0] >= '0' && password[0] <= '9': - break - case len(password) == 8 && password[0] >= '1' && password[0] <= '9': - scratch = true - break - default: - return false, ErrInvalidCode - } - - code, err := strconv.Atoi(password) - - if err != nil { - return false, ErrInvalidCode - } - - if scratch { - return c.checkScratchCodes(code), nil - } - - // we have a counter value we can use - if c.HotpCounter > 0 { - return c.checkHotpCode(code), nil - } - - var t0 int - // assume we're on Time-based OTP - if c.UTC { - t0 = int(time.Now().UTC().Unix() / 30) - } else { - t0 = int(time.Now().Unix() / 30) - } - return c.checkTotpCode(t0, code), nil -} - -// ProvisionURI generates a URI that can be turned into a QR code to configure -// a Google Authenticator mobile app. -func (c *OTPConfig) ProvisionURI(user string) string { - return c.ProvisionURIWithIssuer(user, "") -} - -// ProvisionURIWithIssuer generates a URI that can be turned into a QR code -// to configure a Google Authenticator mobile app. It respects the recommendations -// on how to avoid conflicting accounts. -// -// See https://code.google.com/p/google-authenticator/wiki/ConflictingAccounts -func (c *OTPConfig) ProvisionURIWithIssuer(user string, issuer string) string { - auth := "totp/" - q := make(url.Values) - if c.HotpCounter > 0 { - auth = "hotp/" - q.Add("counter", strconv.Itoa(c.HotpCounter)) - } - q.Add("secret", c.Secret) - if issuer != "" { - q.Add("issuer", issuer) - auth += issuer + ":" - } - - return "otpauth://" + auth + user + "?" + q.Encode() -} |