gotosocial/internal/storage/storage.go
tobi 1e2db7a32f
[feature/bugfix] Probe S3 storage for CSP uri, add config flag for extra URIs (#2134)
* [feature/bugfix] Probe S3 storage for CSP uri, add config flag for extra URIs

* env parsing tests, my coy mistress
2023-08-20 13:35:55 +02:00

274 lines
8.2 KiB
Go

// GoToSocial
// Copyright (C) GoToSocial Authors admin@gotosocial.org
// SPDX-License-Identifier: AGPL-3.0-or-later
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
package storage
import (
"context"
"fmt"
"io"
"mime"
"net/url"
"path"
"time"
"codeberg.org/gruf/go-bytesize"
"codeberg.org/gruf/go-cache/v3/ttl"
"codeberg.org/gruf/go-store/v2/storage"
"github.com/minio/minio-go/v7"
"github.com/minio/minio-go/v7/pkg/credentials"
"github.com/superseriousbusiness/gotosocial/internal/config"
"github.com/superseriousbusiness/gotosocial/internal/gtserror"
"github.com/superseriousbusiness/gotosocial/internal/log"
)
const (
urlCacheTTL = time.Hour * 24
urlCacheExpiryFrequency = time.Minute * 5
)
// PresignedURL represents a pre signed S3 URL with
// an expiry time.
type PresignedURL struct {
*url.URL
Expiry time.Time // link expires at this time
}
var (
// Ptrs to underlying storage library errors.
ErrAlreadyExists = storage.ErrAlreadyExists
ErrNotFound = storage.ErrNotFound
)
// Driver wraps a kv.KVStore to also provide S3 presigned GET URLs.
type Driver struct {
// Underlying storage
Storage storage.Storage
// S3-only parameters
Proxy bool
Bucket string
PresignedCache *ttl.Cache[string, PresignedURL]
}
// Get returns the byte value for key in storage.
func (d *Driver) Get(ctx context.Context, key string) ([]byte, error) {
return d.Storage.ReadBytes(ctx, key)
}
// GetStream returns an io.ReadCloser for the value bytes at key in the storage.
func (d *Driver) GetStream(ctx context.Context, key string) (io.ReadCloser, error) {
return d.Storage.ReadStream(ctx, key)
}
// Put writes the supplied value bytes at key in the storage
func (d *Driver) Put(ctx context.Context, key string, value []byte) (int, error) {
return d.Storage.WriteBytes(ctx, key, value)
}
// PutStream writes the bytes from supplied reader at key in the storage
func (d *Driver) PutStream(ctx context.Context, key string, r io.Reader) (int64, error) {
return d.Storage.WriteStream(ctx, key, r)
}
// Remove attempts to remove the supplied key (and corresponding value) from storage.
func (d *Driver) Delete(ctx context.Context, key string) error {
return d.Storage.Remove(ctx, key)
}
// Has checks if the supplied key is in the storage.
func (d *Driver) Has(ctx context.Context, key string) (bool, error) {
return d.Storage.Stat(ctx, key)
}
// WalkKeys walks the keys in the storage.
func (d *Driver) WalkKeys(ctx context.Context, walk func(context.Context, string) error) error {
return d.Storage.WalkKeys(ctx, storage.WalkKeysOptions{
WalkFn: func(ctx context.Context, entry storage.Entry) error {
if entry.Key == "store.lock" {
return nil // skip this.
}
return walk(ctx, entry.Key)
},
})
}
// Close will close the storage, releasing any file locks.
func (d *Driver) Close() error {
return d.Storage.Close()
}
// URL will return a presigned GET object URL, but only if running on S3 storage with proxying disabled.
func (d *Driver) URL(ctx context.Context, key string) *PresignedURL {
// Check whether S3 *without* proxying is enabled
s3, ok := d.Storage.(*storage.S3Storage)
if !ok || d.Proxy {
return nil
}
// Check cache underlying cache map directly to
// avoid extending the TTL (which cache.Get() does).
d.PresignedCache.Lock()
e, ok := d.PresignedCache.Cache.Get(key)
d.PresignedCache.Unlock()
if ok {
return &e.Value
}
u, err := s3.Client().PresignedGetObject(ctx, d.Bucket, key, urlCacheTTL, url.Values{
"response-content-type": []string{mime.TypeByExtension(path.Ext(key))},
})
if err != nil {
// If URL request fails, fallback is to fetch the file. So ignore the error here
return nil
}
psu := PresignedURL{
URL: u,
Expiry: time.Now().Add(urlCacheTTL), // link expires in 24h time
}
d.PresignedCache.Set(key, psu)
return &psu
}
// ProbeCSPUri returns a URI string that can be added
// to a content-security-policy to allow requests to
// endpoints served by this driver.
//
// If the driver is not backed by non-proxying S3,
// this will return an empty string and no error.
//
// Otherwise, this function probes for a CSP URI by
// doing the following:
//
// 1. Create a temporary file in the S3 bucket.
// 2. Generate a pre-signed URL for that file.
// 3. Extract '[scheme]://[host]' from the URL.
// 4. Remove the temporary file.
// 5. Return the '[scheme]://[host]' string.
func (d *Driver) ProbeCSPUri(ctx context.Context) (string, error) {
// Check whether S3 without proxying
// is enabled. If it's not, there's
// no need to add anything to the CSP.
s3, ok := d.Storage.(*storage.S3Storage)
if !ok || d.Proxy {
return "", nil
}
const cspKey = "gotosocial-csp-probe"
// Create an empty file in S3 storage.
if _, err := d.Put(ctx, cspKey, make([]byte, 0)); err != nil {
return "", gtserror.Newf("error putting file in bucket at key %s: %w", cspKey, err)
}
// Try to clean up file whatever happens.
defer func() {
if err := d.Delete(ctx, cspKey); err != nil {
log.Warnf(ctx, "error deleting file from bucket at key %s (%v); "+
"you may want to remove this file manually from your S3 bucket", cspKey, err)
}
}()
// Get a presigned URL for that empty file.
u, err := s3.Client().PresignedGetObject(ctx, d.Bucket, cspKey, 1*time.Second, nil)
if err != nil {
return "", err
}
// Create a stripped version of the presigned
// URL that includes only the host and scheme.
uStripped := &url.URL{
Scheme: u.Scheme,
Host: u.Host,
}
return uStripped.String(), nil
}
func AutoConfig() (*Driver, error) {
switch backend := config.GetStorageBackend(); backend {
case "s3":
return NewS3Storage()
case "local":
return NewFileStorage()
default:
return nil, fmt.Errorf("invalid storage backend: %s", backend)
}
}
func NewFileStorage() (*Driver, error) {
// Load runtime configuration
basePath := config.GetStorageLocalBasePath()
// Open the disk storage implementation
disk, err := storage.OpenDisk(basePath, &storage.DiskConfig{
// Put the store lockfile in the storage dir itself.
// Normally this would not be safe, since we could end up
// overwriting the lockfile if we store a file called 'store.lock'.
// However, in this case it's OK because the keys are set by
// GtS and not the user, so we know we're never going to overwrite it.
LockFile: path.Join(basePath, "store.lock"),
WriteBufSize: int(16 * bytesize.KiB),
})
if err != nil {
return nil, fmt.Errorf("error opening disk storage: %w", err)
}
return &Driver{
Storage: disk,
}, nil
}
func NewS3Storage() (*Driver, error) {
// Load runtime configuration
endpoint := config.GetStorageS3Endpoint()
access := config.GetStorageS3AccessKey()
secret := config.GetStorageS3SecretKey()
secure := config.GetStorageS3UseSSL()
bucket := config.GetStorageS3BucketName()
// Open the s3 storage implementation
s3, err := storage.OpenS3(endpoint, bucket, &storage.S3Config{
CoreOpts: minio.Options{
Creds: credentials.NewStaticV4(access, secret, ""),
Secure: secure,
},
GetOpts: minio.GetObjectOptions{},
PutOpts: minio.PutObjectOptions{},
PutChunkSize: 5 * 1024 * 1024, // 5MiB
StatOpts: minio.StatObjectOptions{},
RemoveOpts: minio.RemoveObjectOptions{},
ListSize: 200,
})
if err != nil {
return nil, fmt.Errorf("error opening s3 storage: %w", err)
}
// ttl should be lower than the expiry used by S3 to avoid serving invalid URLs
presignedCache := ttl.New[string, PresignedURL](0, 1000, urlCacheTTL-urlCacheExpiryFrequency)
presignedCache.Start(urlCacheExpiryFrequency)
return &Driver{
Proxy: config.GetStorageS3Proxy(),
Bucket: config.GetStorageS3BucketName(),
Storage: s3,
PresignedCache: presignedCache,
}, nil
}