GODRIVER-3454 Support custom AWS credential provider.

ext/awsauth/doc.go

@@ -0,0 +1,24 @@
+// Copyright (C) MongoDB, Inc. 2017-present.
+//
+// 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
+
+// This package allows credential providers and signers in AWS SDK v2 to be
+// supplied to the MongoDB Go Driver for use with the MONGODB-AWS authentication
+// mechanism.
+//
+// This package is a separate module to avoid adding the AWS SDK as a dependency
+// of the main driver. Users who don't need AWS authentication won't need to
+// import the AWS SDK.
+//
+// NewCredentialsProvider() adapts an AWS CredentialsProvider to be used in:
+//
+//	ClientOptions
+//	ClientEncryptionOptions
+//	AutoEncryptionOptions
+//
+// NewSigner() adapts an AWS HTTPSigner to be used in:
+//
+//	ClientOptions
+package awsauth

ext/awsauth/go.mod

@@ -0,0 +1,33 @@
+module go.mongodb.org/mongo-driver/v2/awsauth
+
+go 1.23
+
+require (
+	github.com/aws/aws-sdk-go-v2 v1.41.1
+	github.com/aws/aws-sdk-go-v2/config v1.32.7
+	go.mongodb.org/mongo-driver/v2 v2.0.0-beta2
+)
+
+require (
+	github.com/aws/aws-sdk-go-v2/credentials v1.19.7 // indirect
+	github.com/aws/aws-sdk-go-v2/feature/ec2/imds v1.18.17 // indirect
+	github.com/aws/aws-sdk-go-v2/internal/configsources v1.4.17 // indirect
+	github.com/aws/aws-sdk-go-v2/internal/endpoints/v2 v2.7.17 // indirect
+	github.com/aws/aws-sdk-go-v2/internal/ini v1.8.4 // indirect
+	github.com/aws/aws-sdk-go-v2/service/internal/accept-encoding v1.13.4 // indirect
+	github.com/aws/aws-sdk-go-v2/service/internal/presigned-url v1.13.17 // indirect
+	github.com/aws/aws-sdk-go-v2/service/signin v1.0.5 // indirect
+	github.com/aws/aws-sdk-go-v2/service/sso v1.30.9 // indirect
+	github.com/aws/aws-sdk-go-v2/service/ssooidc v1.35.13 // indirect
+	github.com/aws/aws-sdk-go-v2/service/sts v1.41.6 // indirect
+	github.com/aws/smithy-go v1.24.0 // indirect
+	github.com/golang/snappy v1.0.0 // indirect
+	github.com/klauspost/compress v1.17.6 // indirect
+	github.com/xdg-go/pbkdf2 v1.0.0 // indirect
+	github.com/xdg-go/scram v1.2.0 // indirect
+	github.com/xdg-go/stringprep v1.0.4 // indirect
+	github.com/youmark/pkcs8 v0.0.0-20240726163527-a2c0da244d78 // indirect
+	golang.org/x/crypto v0.33.0 // indirect
+	golang.org/x/sync v0.11.0 // indirect
+	golang.org/x/text v0.22.0 // indirect
+)

ext/awsauth/go.sum

@@ -0,0 +1,76 @@
+github.com/aws/aws-sdk-go-v2 v1.41.1 h1:ABlyEARCDLN034NhxlRUSZr4l71mh+T5KAeGh6cerhU=
+github.com/aws/aws-sdk-go-v2 v1.41.1/go.mod h1:MayyLB8y+buD9hZqkCW3kX1AKq07Y5pXxtgB+rRFhz0=
+github.com/aws/aws-sdk-go-v2/config v1.32.7 h1:vxUyWGUwmkQ2g19n7JY/9YL8MfAIl7bTesIUykECXmY=
+github.com/aws/aws-sdk-go-v2/config v1.32.7/go.mod h1:2/Qm5vKUU/r7Y+zUk/Ptt2MDAEKAfUtKc1+3U1Mo3oY=
+github.com/aws/aws-sdk-go-v2/credentials v1.19.7 h1:tHK47VqqtJxOymRrNtUXN5SP/zUTvZKeLx4tH6PGQc8=
+github.com/aws/aws-sdk-go-v2/credentials v1.19.7/go.mod h1:qOZk8sPDrxhf+4Wf4oT2urYJrYt3RejHSzgAquYeppw=
+github.com/aws/aws-sdk-go-v2/feature/ec2/imds v1.18.17 h1:I0GyV8wiYrP8XpA70g1HBcQO1JlQxCMTW9npl5UbDHY=
+github.com/aws/aws-sdk-go-v2/feature/ec2/imds v1.18.17/go.mod h1:tyw7BOl5bBe/oqvoIeECFJjMdzXoa/dfVz3QQ5lgHGA=
+github.com/aws/aws-sdk-go-v2/internal/configsources v1.4.17 h1:xOLELNKGp2vsiteLsvLPwxC+mYmO6OZ8PYgiuPJzF8U=
+github.com/aws/aws-sdk-go-v2/internal/configsources v1.4.17/go.mod h1:5M5CI3D12dNOtH3/mk6minaRwI2/37ifCURZISxA/IQ=
+github.com/aws/aws-sdk-go-v2/internal/endpoints/v2 v2.7.17 h1:WWLqlh79iO48yLkj1v3ISRNiv+3KdQoZ6JWyfcsyQik=
+github.com/aws/aws-sdk-go-v2/internal/endpoints/v2 v2.7.17/go.mod h1:EhG22vHRrvF8oXSTYStZhJc1aUgKtnJe+aOiFEV90cM=
+github.com/aws/aws-sdk-go-v2/internal/ini v1.8.4 h1:WKuaxf++XKWlHWu9ECbMlha8WOEGm0OUEZqm4K/Gcfk=
+github.com/aws/aws-sdk-go-v2/internal/ini v1.8.4/go.mod h1:ZWy7j6v1vWGmPReu0iSGvRiise4YI5SkR3OHKTZ6Wuc=
+github.com/aws/aws-sdk-go-v2/service/internal/accept-encoding v1.13.4 h1:0ryTNEdJbzUCEWkVXEXoqlXV72J5keC1GvILMOuD00E=
+github.com/aws/aws-sdk-go-v2/service/internal/accept-encoding v1.13.4/go.mod h1:HQ4qwNZh32C3CBeO6iJLQlgtMzqeG17ziAA/3KDJFow=
+github.com/aws/aws-sdk-go-v2/service/internal/presigned-url v1.13.17 h1:RuNSMoozM8oXlgLG/n6WLaFGoea7/CddrCfIiSA+xdY=
+github.com/aws/aws-sdk-go-v2/service/internal/presigned-url v1.13.17/go.mod h1:F2xxQ9TZz5gDWsclCtPQscGpP0VUOc8RqgFM3vDENmU=
+github.com/aws/aws-sdk-go-v2/service/signin v1.0.5 h1:VrhDvQib/i0lxvr3zqlUwLwJP4fpmpyD9wYG1vfSu+Y=
+github.com/aws/aws-sdk-go-v2/service/signin v1.0.5/go.mod h1:k029+U8SY30/3/ras4G/Fnv/b88N4mAfliNn08Dem4M=
+github.com/aws/aws-sdk-go-v2/service/sso v1.30.9 h1:v6EiMvhEYBoHABfbGB4alOYmCIrcgyPPiBE1wZAEbqk=
+github.com/aws/aws-sdk-go-v2/service/sso v1.30.9/go.mod h1:yifAsgBxgJWn3ggx70A3urX2AN49Y5sJTD1UQFlfqBw=
+github.com/aws/aws-sdk-go-v2/service/ssooidc v1.35.13 h1:gd84Omyu9JLriJVCbGApcLzVR3XtmC4ZDPcAI6Ftvds=
+github.com/aws/aws-sdk-go-v2/service/ssooidc v1.35.13/go.mod h1:sTGThjphYE4Ohw8vJiRStAcu3rbjtXRsdNB0TvZ5wwo=
+github.com/aws/aws-sdk-go-v2/service/sts v1.41.6 h1:5fFjR/ToSOzB2OQ/XqWpZBmNvmP/pJ1jOWYlFDJTjRQ=
+github.com/aws/aws-sdk-go-v2/service/sts v1.41.6/go.mod h1:qgFDZQSD/Kys7nJnVqYlWKnh0SSdMjAi0uSwON4wgYQ=
+github.com/aws/smithy-go v1.24.0 h1:LpilSUItNPFr1eY85RYgTIg5eIEPtvFbskaFcmmIUnk=
+github.com/aws/smithy-go v1.24.0/go.mod h1:LEj2LM3rBRQJxPZTB4KuzZkaZYnZPnvgIhb4pu07mx0=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
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+go.mongodb.org/mongo-driver/v2 v2.0.0-beta2/go.mod h1:UGLb3ZgEzaY0cCbJpH9UFt9B6gEXiTPzsnJS38nBeoU=
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ext/awsauth/mongoaws.go

@@ -0,0 +1,90 @@
+// Copyright (C) MongoDB, Inc. 2017-present.
+//
+// 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
+
+package awsauth
+
+import (
+	"context"
+	"crypto/sha256"
+	"encoding/hex"
+	"errors"
+	"net/http"
+	"time"
+
+	"github.com/aws/aws-sdk-go-v2/aws"
+	v4 "github.com/aws/aws-sdk-go-v2/aws/signer/v4"
+
+	"go.mongodb.org/mongo-driver/v2/mongo/options"
+)
+
+const (
+	// emptyStringSHA256 is a SHA256 of an empty string
+	emptyStringSHA256 = `e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855`
+)
+
+var _ options.AWSCredentialsProvider = (*CredentialsProvider)(nil)
+
+// CredentialsProvider adapts an AWS SDK v2 CredentialsProvider to the
+// options.AWSCredentialsProvider interface used by the MongoDB Go Driver.
+type CredentialsProvider struct {
+	provider aws.CredentialsProvider
+}
+
+// NewCredentialsProvider returns a CredentialsProvider that wraps AWS
+// CredentialsProvider. CredentialsProvider is expected to not be nil.
+func NewCredentialsProvider(credentialsProvider aws.CredentialsProvider) (*CredentialsProvider, error) {
+	if credentialsProvider == nil {
+		return nil, errors.New("nil provider")
+	}
+	return &CredentialsProvider{
+		provider: credentialsProvider,
+	}, nil
+}
+
+// Retrieve returns the credentials.
+func (p *CredentialsProvider) Retrieve(ctx context.Context) (options.AWSCredentials, error) {
+	creds, err := p.provider.Retrieve(ctx)
+	return options.AWSCredentials(creds), err
+}
+
+var _ options.AWSSigner = (*Signer)(nil)
+
+// Signer adapts an AWS SDK v2 SigV4 HTTP signer to the options.AWSSigner
+// interface used by the MongoDB Go Driver.
+type Signer struct {
+	signer v4.HTTPSigner
+}
+
+// NewSigner creates a new Signer from the provided AWS HTTPSigner. HTTPSigner
+// is expected to not be nil.
+func NewSigner(httpSigner v4.HTTPSigner) (*Signer, error) {
+	if httpSigner == nil {
+		return nil, errors.New("nil httpSigner")
+	}
+	return &Signer{
+		signer: httpSigner,
+	}, nil
+}
+
+// Sign signs AWS SigV4 requests.  The payload parameter should be the raw
+// request body. This method computes the SHA256 hash of the payload before
+// signing. If payload is empty, the precomputed hash of an empty string is
+// used.
+func (s *Signer) Sign(
+	ctx context.Context, creds options.AWSCredentials, r *http.Request,
+	payload, service, region string, signingTime time.Time,
+) error {
+	if len(payload) == 0 {
+		payload = emptyStringSHA256
+	} else {
+		hash := sha256.Sum256([]byte(payload))
+		payload = hex.EncodeToString(hash[:])
+	}
+	if creds.SessionToken != "" {
+		r.Header.Set("X-Amz-Security-Token", creds.SessionToken)
+	}
+	return s.signer.SignHTTP(ctx, aws.Credentials(creds), r, payload, service, region, signingTime)
+}

ext/awsauth/mongoaws_example_test.go

@@ -0,0 +1,64 @@
+// Copyright (C) MongoDB, Inc. 2017-present.
+//
+// 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
+
+package awsauth
+
+import (
+	"context"
+
+	v4 "github.com/aws/aws-sdk-go-v2/aws/signer/v4"
+	"github.com/aws/aws-sdk-go-v2/config"
+	"go.mongodb.org/mongo-driver/v2/mongo"
+	"go.mongodb.org/mongo-driver/v2/mongo/options"
+)
+
+func ExampleNewCredentialsProvider() {
+	cfg, err := config.LoadDefaultConfig(context.TODO())
+	if err != nil {
+		panic(err)
+	}
+	awsCredentialProvider, err := NewCredentialsProvider(cfg.Credentials)
+	if err != nil {
+		panic(err)
+	}
+	credential := options.Credential{
+		AuthMechanism:          "MONGODB-AWS",
+		AWSCredentialsProvider: awsCredentialProvider,
+	}
+	client, err := mongo.Connect(
+		options.Client().SetAuth(credential))
+	if err != nil {
+		panic(err)
+	}
+	_ = client
+}
+
+func ExampleNewSigner() {
+	cfg, err := config.LoadDefaultConfig(context.TODO())
+	if err != nil {
+		panic(err)
+	}
+	awsCredentialProvider, err := NewCredentialsProvider(cfg.Credentials)
+	if err != nil {
+		panic(err)
+	}
+	awsSigner, err := NewSigner(v4.NewSigner())
+	if err != nil {
+		panic(err)
+	}
+	_ = awsSigner
+	credential := options.Credential{
+		AuthMechanism:          "MONGODB-AWS",
+		AWSCredentialsProvider: awsCredentialProvider,
+		AWSSigner:              awsSigner,
+	}
+	client, err := mongo.Connect(
+		options.Client().SetAuth(credential))
+	if err != nil {
+		panic(err)
+	}
+	_ = client
+}

go.work

@@ -9,4 +9,5 @@ use (
 	./internal/cmd/faas/awslambda/mongodb
 	./internal/test/compilecheck
 	./internal/test/goleak
+	./ext/awsauth
 )

internal/aws/credentials/chain_provider.go

@@ -11,25 +11,20 @@
 package credentials
 
 import (
+	"context"
+	"errors"
+
 	"go.mongodb.org/mongo-driver/v2/internal/aws/awserr"
 )
 
-// A ChainProvider will search for a provider which returns credentials
-// and cache that provider until Retrieve is called again.
-//
 // The ChainProvider provides a way of chaining multiple providers together
 // which will pick the first available using priority order of the Providers
 // in the list.
 //
 // If none of the Providers retrieve valid credentials Value, ChainProvider's
-// Retrieve() will return the error ErrNoValidProvidersFoundInChain.
-//
-// If a Provider is found which returns valid credentials Value ChainProvider
-// will cache that Provider for all calls to IsExpired(), until Retrieve is
-// called again.
+// Retrieve() will return an error.
 type ChainProvider struct {
 	Providers []Provider
-	curr      Provider
 }
 
 // NewChainCredentials returns a pointer to a new Credentials object
@@ -42,31 +37,19 @@ func NewChainCredentials(providers []Provider) *Credentials {
 
 // Retrieve returns the credentials value or error if no provider returned
 // without error.
-//
-// If a provider is found it will be cached and any calls to IsExpired()
-// will return the expired state of the cached provider.
-func (c *ChainProvider) Retrieve() (Value, error) {
+func (c *ChainProvider) Retrieve(ctx context.Context) (Value, error) {
 	errs := make([]error, 0, len(c.Providers))
 	for _, p := range c.Providers {
-		creds, err := p.Retrieve()
+		creds, err := p.Retrieve(ctx)
 		if err == nil {
-			c.curr = p
-			return creds, nil
+			if !creds.Expired() && creds.HasKeys() {
+				return creds, nil
+			}
+			err = errors.New("credentials are invalid")
 		}
 		errs = append(errs, err)
 	}
-	c.curr = nil
 
 	err := awserr.NewBatchError("NoCredentialProviders", "no valid providers in chain", errs)
 	return Value{}, err
 }
-
-// IsExpired will returned the expired state of the currently cached provider
-// if there is one.  If there is no current provider, true will be returned.
-func (c *ChainProvider) IsExpired() bool {
-	if c.curr != nil {
-		return c.curr.IsExpired()
-	}
-
-	return true
-}