func decodeDockerConfigFieldAuth(field string) (username, password string, err error) {

	var decoded []byte

	// StdEncoding can only decode padded string
	// RawStdEncoding can only decode unpadded string
	if strings.HasSuffix(strings.TrimSpace(field), "=") {
		// decode padded data
		decoded, err = base64.StdEncoding.DecodeString(field)
	} else {
		// decode unpadded data
		decoded, err = base64.RawStdEncoding.DecodeString(field)

	credentials := `{
	"auths":{
		"%v":{
			"username": "%v",
			"password": "%v",
			"email": "******@****.***",
			"auth": "%v"
		}
	}
}`
	auth := base64.StdEncoding.EncodeToString([]byte(user + ":" + passwd))
	return fmt.Sprintf(credentials, registry, user, passwd, auth)

	// the chance of colliding hash P(N,X) approximates to 1-e^(-(N^2)/2^(8X+1)).
	// P(10,000, 8) ~= 2.7*10^(-12), which is low enough.
	// See https://en.wikipedia.org/wiki/Birthday_problem#Approximations.
	return base64.StdEncoding.EncodeToString(bytes[:8])

		if s, _ := getLine(restOfEndLine); len(s) != 0 {
			continue
		}

		base64Data := removeSpacesAndTabs(rest[:endIndex])
		p.Bytes = make([]byte, base64.StdEncoding.DecodedLen(len(base64Data)))
		n, err := base64.StdEncoding.Decode(p.Bytes, base64Data)
		if err != nil {
			continue
		}
		p.Bytes = p.Bytes[:n]

		// the -1 is because we might have only matched pemEnd without the

		"X-Amz-Server-Side-Encryption-Context":        []string{base64.StdEncoding.EncodeToString([]byte("{}"))},
	}, ShouldFail: false}, // 3
	{Header: http.Header{
		"X-Amz-Server-Side-Encryption":                []string{"aws:kms"},
		"X-Amz-Server-Side-Encryption-Aws-Kms-Key-Id": []string{"s3-007-293847485-724784"},
		"X-Amz-Server-Side-Encryption-Context":        []string{base64.StdEncoding.EncodeToString([]byte(`{"bucket": "some-bucket"}`))},

			t.Fatalf("Test %d: ciphertext mismatch: got %x - want %x", i, key.Ciphertext, test.Key.Ciphertext)
		}
	}
}

func mustDecodeB64(s string) []byte {
	b, err := base64.StdEncoding.DecodeString(s)
	if err != nil {
		panic(err)
	}
	return b

	if err != nil {
		return nil, err
	}

	// Use base64 of encKey as the key into the cache because hashicorp/golang-lru
	// cannot hash []uint8.
	if t.cacheEnabled {
		t.transformers.Add(base64.StdEncoding.EncodeToString(encKey), transformer)
		metrics.RecordDekCacheFillPercent(float64(t.transformers.Len()) / float64(t.cacheSize))
	}
	return transformer, nil
}

	// as Base64 encoding of a value is not unique:
	// For example "aGVsbG8=" and "aGVsbG8=\r" will result in the same byte slice.
	signature1, err := base64.StdEncoding.DecodeString(sig1)
	if err != nil {
		return false
	}
	signature2, err := base64.StdEncoding.DecodeString(sig2)
	if err != nil {
		return false
	}
	return subtle.ConstantTimeCompare(signature1, signature2) == 1
}

// Return canonical headers.

	rCASecret := secret.GetValidationContext()
	if rCASecret != nil {
		trustCA := rCASecret.GetTrustedCa()
		if trustCA != nil {
			inlineBytes := trustCA.GetInlineBytes()
			if inlineBytes != nil {
				returnStr = base64.StdEncoding.EncodeToString(inlineBytes)
				returnErr = nil
			} else {
				returnStr = ""
				returnErr = fmt.Errorf("can not retrieve inlineBytes from trustCA section")
			}
		} else {
			returnStr = ""

		t.Fatalf("error running profile collection: %v\noutput: %s", err, out)
	}

	// Log the binary output for debugging failures.
	b64 := make([]byte, base64.StdEncoding.EncodedLen(len(out)))
	base64.StdEncoding.Encode(b64, out)
	t.Logf("Output in base64.StdEncoding: %s", b64)

	p, err := profile.Parse(bytes.NewReader(out))
	if err != nil {
		t.Fatalf("Parse got err %v want nil", err)
	}