peridot/vendor/cloud.google.com/go/auth/internal/internal.go
2024-10-16 12:56:53 +02:00

199 lines
5.6 KiB
Go

// Copyright 2023 Google LLC
//
// 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 internal
import (
"context"
"crypto/rsa"
"crypto/x509"
"encoding/json"
"encoding/pem"
"errors"
"fmt"
"io"
"net/http"
"os"
"sync"
"time"
"cloud.google.com/go/compute/metadata"
)
const (
// TokenTypeBearer is the auth header prefix for bearer tokens.
TokenTypeBearer = "Bearer"
// QuotaProjectEnvVar is the environment variable for setting the quota
// project.
QuotaProjectEnvVar = "GOOGLE_CLOUD_QUOTA_PROJECT"
projectEnvVar = "GOOGLE_CLOUD_PROJECT"
maxBodySize = 1 << 20
// DefaultUniverseDomain is the default value for universe domain.
// Universe domain is the default service domain for a given Cloud universe.
DefaultUniverseDomain = "googleapis.com"
)
// CloneDefaultClient returns a [http.Client] with some good defaults.
func CloneDefaultClient() *http.Client {
return &http.Client{
Transport: http.DefaultTransport.(*http.Transport).Clone(),
Timeout: 30 * time.Second,
}
}
// ParseKey converts the binary contents of a private key file
// to an *rsa.PrivateKey. It detects whether the private key is in a
// PEM container or not. If so, it extracts the the private key
// from PEM container before conversion. It only supports PEM
// containers with no passphrase.
func ParseKey(key []byte) (*rsa.PrivateKey, error) {
block, _ := pem.Decode(key)
if block != nil {
key = block.Bytes
}
parsedKey, err := x509.ParsePKCS8PrivateKey(key)
if err != nil {
parsedKey, err = x509.ParsePKCS1PrivateKey(key)
if err != nil {
return nil, fmt.Errorf("private key should be a PEM or plain PKCS1 or PKCS8: %w", err)
}
}
parsed, ok := parsedKey.(*rsa.PrivateKey)
if !ok {
return nil, errors.New("private key is invalid")
}
return parsed, nil
}
// GetQuotaProject retrieves quota project with precedence being: override,
// environment variable, creds json file.
func GetQuotaProject(b []byte, override string) string {
if override != "" {
return override
}
if env := os.Getenv(QuotaProjectEnvVar); env != "" {
return env
}
if b == nil {
return ""
}
var v struct {
QuotaProject string `json:"quota_project_id"`
}
if err := json.Unmarshal(b, &v); err != nil {
return ""
}
return v.QuotaProject
}
// GetProjectID retrieves project with precedence being: override,
// environment variable, creds json file.
func GetProjectID(b []byte, override string) string {
if override != "" {
return override
}
if env := os.Getenv(projectEnvVar); env != "" {
return env
}
if b == nil {
return ""
}
var v struct {
ProjectID string `json:"project_id"` // standard service account key
Project string `json:"project"` // gdch key
}
if err := json.Unmarshal(b, &v); err != nil {
return ""
}
if v.ProjectID != "" {
return v.ProjectID
}
return v.Project
}
// DoRequest executes the provided req with the client. It reads the response
// body, closes it, and returns it.
func DoRequest(client *http.Client, req *http.Request) (*http.Response, []byte, error) {
resp, err := client.Do(req)
if err != nil {
return nil, nil, err
}
defer resp.Body.Close()
body, err := ReadAll(io.LimitReader(resp.Body, maxBodySize))
if err != nil {
return nil, nil, err
}
return resp, body, nil
}
// ReadAll consumes the whole reader and safely reads the content of its body
// with some overflow protection.
func ReadAll(r io.Reader) ([]byte, error) {
return io.ReadAll(io.LimitReader(r, maxBodySize))
}
// StaticCredentialsProperty is a helper for creating static credentials
// properties.
func StaticCredentialsProperty(s string) StaticProperty {
return StaticProperty(s)
}
// StaticProperty always returns that value of the underlying string.
type StaticProperty string
// GetProperty loads the properly value provided the given context.
func (p StaticProperty) GetProperty(context.Context) (string, error) {
return string(p), nil
}
// ComputeUniverseDomainProvider fetches the credentials universe domain from
// the google cloud metadata service.
type ComputeUniverseDomainProvider struct {
universeDomainOnce sync.Once
universeDomain string
universeDomainErr error
}
// GetProperty fetches the credentials universe domain from the google cloud
// metadata service.
func (c *ComputeUniverseDomainProvider) GetProperty(ctx context.Context) (string, error) {
c.universeDomainOnce.Do(func() {
c.universeDomain, c.universeDomainErr = getMetadataUniverseDomain(ctx)
})
if c.universeDomainErr != nil {
return "", c.universeDomainErr
}
return c.universeDomain, nil
}
// httpGetMetadataUniverseDomain is a package var for unit test substitution.
var httpGetMetadataUniverseDomain = func(ctx context.Context) (string, error) {
client := metadata.NewClient(&http.Client{Timeout: time.Second})
return client.GetWithContext(ctx, "universe/universe_domain")
}
func getMetadataUniverseDomain(ctx context.Context) (string, error) {
universeDomain, err := httpGetMetadataUniverseDomain(ctx)
if err == nil {
return universeDomain, nil
}
if _, ok := err.(metadata.NotDefinedError); ok {
// http.StatusNotFound (404)
return DefaultUniverseDomain, nil
}
return "", err
}