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mirror of https://github.com/go-gitea/gitea synced 2024-11-15 06:34:25 +00:00
gitea/modules/lfstransfer/backend/backend.go
ConcurrentCrab 8a9fd7f771
Add pure SSH LFS support (#31516)
Fixes #17554
/claim #17554

Docs PR https://gitea.com/gitea/docs/pulls/49

To test, run pushes like: `GIT_TRACE=1` git push. The trace output
should mention "pure SSH connection".
2024-09-27 10:27:37 -04:00

302 lines
8.9 KiB
Go

// Copyright 2024 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT
package backend
import (
"bytes"
"context"
"encoding/base64"
"fmt"
"io"
"net/http"
"net/url"
"strconv"
"code.gitea.io/gitea/modules/json"
"code.gitea.io/gitea/modules/lfs"
"code.gitea.io/gitea/modules/setting"
"github.com/charmbracelet/git-lfs-transfer/transfer"
)
// Version is the git-lfs-transfer protocol version number.
const Version = "1"
// Capabilities is a list of Git LFS capabilities supported by this package.
var Capabilities = []string{
"version=" + Version,
"locking",
}
var _ transfer.Backend = &GiteaBackend{}
// GiteaBackend is an adapter between git-lfs-transfer library and Gitea's internal LFS API
type GiteaBackend struct {
ctx context.Context
server *url.URL
op string
token string
itoken string
logger transfer.Logger
}
func New(ctx context.Context, repo, op, token string, logger transfer.Logger) (transfer.Backend, error) {
// runServ guarantees repo will be in form [owner]/[name].git
server, err := url.Parse(setting.LocalURL)
if err != nil {
return nil, err
}
server = server.JoinPath("api/internal/repo", repo, "info/lfs")
return &GiteaBackend{ctx: ctx, server: server, op: op, token: token, itoken: fmt.Sprintf("Bearer %s", setting.InternalToken), logger: logger}, nil
}
// Batch implements transfer.Backend
func (g *GiteaBackend) Batch(_ string, pointers []transfer.BatchItem, args transfer.Args) ([]transfer.BatchItem, error) {
reqBody := lfs.BatchRequest{Operation: g.op}
if transfer, ok := args[argTransfer]; ok {
reqBody.Transfers = []string{transfer}
}
if ref, ok := args[argRefname]; ok {
reqBody.Ref = &lfs.Reference{Name: ref}
}
reqBody.Objects = make([]lfs.Pointer, len(pointers))
for i := range pointers {
reqBody.Objects[i].Oid = pointers[i].Oid
reqBody.Objects[i].Size = pointers[i].Size
}
bodyBytes, err := json.Marshal(reqBody)
if err != nil {
g.logger.Log("json marshal error", err)
return nil, err
}
url := g.server.JoinPath("objects/batch").String()
headers := map[string]string{
headerAuthorisation: g.itoken,
headerAuthX: g.token,
headerAccept: mimeGitLFS,
headerContentType: mimeGitLFS,
}
req := newInternalRequest(g.ctx, url, http.MethodPost, headers, bodyBytes)
resp, err := req.Response()
if err != nil {
g.logger.Log("http request error", err)
return nil, err
}
if resp.StatusCode != http.StatusOK {
g.logger.Log("http statuscode error", resp.StatusCode, statusCodeToErr(resp.StatusCode))
return nil, statusCodeToErr(resp.StatusCode)
}
defer resp.Body.Close()
respBytes, err := io.ReadAll(resp.Body)
if err != nil {
g.logger.Log("http read error", err)
return nil, err
}
var respBody lfs.BatchResponse
err = json.Unmarshal(respBytes, &respBody)
if err != nil {
g.logger.Log("json umarshal error", err)
return nil, err
}
// rebuild slice, we can't rely on order in resp being the same as req
pointers = pointers[:0]
opNum := opMap[g.op]
for _, obj := range respBody.Objects {
pointer := transfer.Pointer{Oid: obj.Pointer.Oid, Size: obj.Pointer.Size}
item := transfer.BatchItem{Pointer: pointer, Args: map[string]string{}}
switch opNum {
case opDownload:
if action, ok := obj.Actions[actionDownload]; ok {
item.Present = true
idMap := obj.Actions
idMapBytes, err := json.Marshal(idMap)
if err != nil {
g.logger.Log("json marshal error", err)
return nil, err
}
idMapStr := base64.StdEncoding.EncodeToString(idMapBytes)
item.Args[argID] = idMapStr
if authHeader, ok := action.Header[headerAuthorisation]; ok {
authHeaderB64 := base64.StdEncoding.EncodeToString([]byte(authHeader))
item.Args[argToken] = authHeaderB64
}
if action.ExpiresAt != nil {
item.Args[argExpiresAt] = action.ExpiresAt.String()
}
} else {
// must be an error, but the SSH protocol can't propagate individual errors
g.logger.Log("object not found", obj.Pointer.Oid, obj.Pointer.Size)
item.Present = false
}
case opUpload:
if action, ok := obj.Actions[actionUpload]; ok {
item.Present = false
idMap := obj.Actions
idMapBytes, err := json.Marshal(idMap)
if err != nil {
g.logger.Log("json marshal error", err)
return nil, err
}
idMapStr := base64.StdEncoding.EncodeToString(idMapBytes)
item.Args[argID] = idMapStr
if authHeader, ok := action.Header[headerAuthorisation]; ok {
authHeaderB64 := base64.StdEncoding.EncodeToString([]byte(authHeader))
item.Args[argToken] = authHeaderB64
}
if action.ExpiresAt != nil {
item.Args[argExpiresAt] = action.ExpiresAt.String()
}
} else {
item.Present = true
}
}
pointers = append(pointers, item)
}
return pointers, nil
}
// Download implements transfer.Backend. The returned reader must be closed by the
// caller.
func (g *GiteaBackend) Download(oid string, args transfer.Args) (io.ReadCloser, int64, error) {
idMapStr, exists := args[argID]
if !exists {
return nil, 0, ErrMissingID
}
idMapBytes, err := base64.StdEncoding.DecodeString(idMapStr)
if err != nil {
g.logger.Log("base64 decode error", err)
return nil, 0, transfer.ErrCorruptData
}
idMap := map[string]*lfs.Link{}
err = json.Unmarshal(idMapBytes, &idMap)
if err != nil {
g.logger.Log("json unmarshal error", err)
return nil, 0, transfer.ErrCorruptData
}
action, exists := idMap[actionDownload]
if !exists {
g.logger.Log("argument id incorrect")
return nil, 0, transfer.ErrCorruptData
}
url := action.Href
headers := map[string]string{
headerAuthorisation: g.itoken,
headerAuthX: g.token,
headerAccept: mimeOctetStream,
}
req := newInternalRequest(g.ctx, url, http.MethodGet, headers, nil)
resp, err := req.Response()
if err != nil {
return nil, 0, err
}
if resp.StatusCode != http.StatusOK {
return nil, 0, statusCodeToErr(resp.StatusCode)
}
defer resp.Body.Close()
respBytes, err := io.ReadAll(resp.Body)
if err != nil {
return nil, 0, err
}
respSize := int64(len(respBytes))
respBuf := io.NopCloser(bytes.NewBuffer(respBytes))
return respBuf, respSize, nil
}
// StartUpload implements transfer.Backend.
func (g *GiteaBackend) Upload(oid string, size int64, r io.Reader, args transfer.Args) error {
idMapStr, exists := args[argID]
if !exists {
return ErrMissingID
}
idMapBytes, err := base64.StdEncoding.DecodeString(idMapStr)
if err != nil {
g.logger.Log("base64 decode error", err)
return transfer.ErrCorruptData
}
idMap := map[string]*lfs.Link{}
err = json.Unmarshal(idMapBytes, &idMap)
if err != nil {
g.logger.Log("json unmarshal error", err)
return transfer.ErrCorruptData
}
action, exists := idMap[actionUpload]
if !exists {
g.logger.Log("argument id incorrect")
return transfer.ErrCorruptData
}
url := action.Href
headers := map[string]string{
headerAuthorisation: g.itoken,
headerAuthX: g.token,
headerContentType: mimeOctetStream,
headerContentLength: strconv.FormatInt(size, 10),
}
reqBytes, err := io.ReadAll(r)
if err != nil {
return err
}
req := newInternalRequest(g.ctx, url, http.MethodPut, headers, reqBytes)
resp, err := req.Response()
if err != nil {
return err
}
if resp.StatusCode != http.StatusOK {
return statusCodeToErr(resp.StatusCode)
}
return nil
}
// Verify implements transfer.Backend.
func (g *GiteaBackend) Verify(oid string, size int64, args transfer.Args) (transfer.Status, error) {
reqBody := lfs.Pointer{Oid: oid, Size: size}
bodyBytes, err := json.Marshal(reqBody)
if err != nil {
return transfer.NewStatus(transfer.StatusInternalServerError), err
}
idMapStr, exists := args[argID]
if !exists {
return transfer.NewStatus(transfer.StatusBadRequest, "missing argument: id"), ErrMissingID
}
idMapBytes, err := base64.StdEncoding.DecodeString(idMapStr)
if err != nil {
g.logger.Log("base64 decode error", err)
return transfer.NewStatus(transfer.StatusBadRequest, "corrupt argument: id"), transfer.ErrCorruptData
}
idMap := map[string]*lfs.Link{}
err = json.Unmarshal(idMapBytes, &idMap)
if err != nil {
g.logger.Log("json unmarshal error", err)
return transfer.NewStatus(transfer.StatusBadRequest, "corrupt argument: id"), transfer.ErrCorruptData
}
action, exists := idMap[actionVerify]
if !exists {
// the server sent no verify action
return transfer.SuccessStatus(), nil
}
url := action.Href
headers := map[string]string{
headerAuthorisation: g.itoken,
headerAuthX: g.token,
headerAccept: mimeGitLFS,
headerContentType: mimeGitLFS,
}
req := newInternalRequest(g.ctx, url, http.MethodPost, headers, bodyBytes)
resp, err := req.Response()
if err != nil {
return transfer.NewStatus(transfer.StatusInternalServerError), err
}
if resp.StatusCode != http.StatusOK {
return transfer.NewStatus(uint32(resp.StatusCode), http.StatusText(resp.StatusCode)), statusCodeToErr(resp.StatusCode)
}
return transfer.SuccessStatus(), nil
}
// LockBackend implements transfer.Backend.
func (g *GiteaBackend) LockBackend(_ transfer.Args) transfer.LockBackend {
return newGiteaLockBackend(g)
}