From 020e4a8f5622944c2a49a7eaeefd198c8a25bfd8 Mon Sep 17 00:00:00 2001 From: fiatjaf Date: Mon, 1 Dec 2025 09:42:34 -0300 Subject: [PATCH] grasp: spread stuff into multiple files. --- khatru/grasp/handlers.go | 86 +++++ khatru/grasp/helpers.go | 175 ++++++++++ khatru/grasp/info.go | 104 ++++++ khatru/grasp/read.go | 117 +++++++ khatru/grasp/server.go | 726 --------------------------------------- khatru/grasp/write.go | 305 ++++++++++++++++ 6 files changed, 787 insertions(+), 726 deletions(-) create mode 100644 khatru/grasp/handlers.go create mode 100644 khatru/grasp/helpers.go create mode 100644 khatru/grasp/info.go create mode 100644 khatru/grasp/read.go create mode 100644 khatru/grasp/write.go diff --git a/khatru/grasp/handlers.go b/khatru/grasp/handlers.go new file mode 100644 index 0000000..1521188 --- /dev/null +++ b/khatru/grasp/handlers.go @@ -0,0 +1,86 @@ +package grasp + +import ( + "fmt" + "net/http" + "regexp" + "strings" + + "fiatjaf.com/nostr" + "fiatjaf.com/nostr/nip19" +) + +var asciiPattern = regexp.MustCompile(`^[\w-.]+$`) + +// handleGitRequest validates .git suffix and decodes npub, then calls the handler +func (gs *GraspServer) handleGitRequest( + w http.ResponseWriter, + r *http.Request, + base http.Handler, + handler func(http.ResponseWriter, + *http.Request, + nostr.PubKey, + string, + ), +) { + npub := r.PathValue("npub") + repoWithGit := r.PathValue("repo") + + // validate .git suffix + if !strings.HasSuffix(repoWithGit, ".git") { + base.ServeHTTP(w, r) + return + } + + repoName := strings.TrimSuffix(repoWithGit, ".git") + + // validate repo name + if !asciiPattern.MatchString(repoName) { + http.Error(w, "invalid repository name", 400) + return + } + + // decode npub to pubkey + _, value, err := nip19.Decode(npub) + if err != nil { + http.Error(w, "invalid npub", 400) + return + } + pk, ok := value.(nostr.PubKey) + if !ok { + http.Error(w, "invalid npub", 400) + return + } + + handler(w, r, pk, repoName) +} + +// serveRepoPage serves a webpage for the repository +func (gs *GraspServer) serveRepoPage(w http.ResponseWriter, r *http.Request, npub, repoName string) { + w.Header().Set("Content-Type", "text/html") + html := fmt.Sprintf(` + + + %s/%s - NIP-34 Git Repository + + + +

Repository: %s/%s

+
+

This is a NIP-34 git repository served over Nostr.

+
+

Clone this repository

+

Use a git-nostr client to clone:

+ 
git clone %s/%s/%s.git
+

Browse

+

Use a git-nostr web client or Nostr client to browse this repository.

+ +`, npub, repoName, npub, repoName, r.Host, npub, repoName) + fmt.Fprint(w, html) +} diff --git a/khatru/grasp/helpers.go b/khatru/grasp/helpers.go new file mode 100644 index 0000000..87efa19 --- /dev/null +++ b/khatru/grasp/helpers.go @@ -0,0 +1,175 @@ +package grasp + +import ( + "bytes" + "context" + "errors" + "fmt" + "io" + "net/http" + "slices" + "strings" + + "fiatjaf.com/nostr" + "fiatjaf.com/nostr/nip34" + "github.com/go-git/go-git/v5/plumbing/format/pktline" +) + +const zeroRef = "0000000000000000000000000000000000000000" + +// validatePush checks if a push is authorized via NIP-34 repository state events +func (gs *GraspServer) validatePush( + ctx context.Context, + pubkey nostr.PubKey, + repoName string, + bodyBytes []byte, +) error { + // query for repository state events (kind 30618) + if gs.Relay.QueryStored == nil { + return errors.New("relay has no QueryStored function") + } + + // check state + var state nip34.RepositoryState + for evt := range gs.Relay.QueryStored(ctx, nostr.Filter{ + Kinds: []nostr.Kind{nostr.KindRepositoryState}, + Authors: []nostr.PubKey{pubkey}, + Tags: nostr.TagMap{"d": []string{repoName}}, + Limit: 1, + }) { + state = nip34.ParseRepositoryState(evt) + } + if state.Event.ID == nostr.ZeroID { + return fmt.Errorf("no state found for repository '%s'", repoName) + } + + // get repository announcement to check maintainers + var announcement nip34.Repository + for evt := range gs.Relay.QueryStored(ctx, nostr.Filter{ + Kinds: []nostr.Kind{nostr.KindRepositoryAnnouncement}, + Authors: []nostr.PubKey{pubkey}, + Tags: nostr.TagMap{"d": []string{repoName}}, + Limit: 1, + }) { + announcement = nip34.ParseRepository(evt) + } + if announcement.Event.ID == nostr.ZeroID { + return fmt.Errorf("no announcement found for repository '%s'", repoName) + } + + // ensure pusher is authorized (owner or maintainer) + if pubkey != announcement.PubKey && !slices.Contains(announcement.Maintainers, pubkey) { + return fmt.Errorf("pusher '%s' is not authorized for repository '%s'", pubkey, repoName) + } + + // parse pktline to extract and validate all push refs + pkt := pktline.NewScanner(bytes.NewReader(bodyBytes)) + for pkt.Scan() { + if err := pkt.Err(); err != nil { + return fmt.Errorf("invalid pkt: %v", err) + } + line := string(pkt.Bytes()) + if len(line) < 40 { + continue + } + + spl := strings.Split(line, " ") + from := spl[0] + to := spl[1] + ref := strings.TrimRight(spl[2], "\x00") + + // handle refs/nostr/ pushes + if strings.HasPrefix(ref, "refs/nostr/") { + // query for the event + eventId := ref[11:] + id, err := nostr.IDFromHex(eventId) + if err != nil { + return fmt.Errorf("push rejected: invalid event id %s", eventId) + } + var foundEvent bool + for evt := range gs.Relay.QueryStored(ctx, nostr.Filter{ + IDs: []nostr.ID{id}, + }) { + // check if event has a "c" tag matching the commit + hasMatchingCommit := false + for _, tag := range evt.Tags { + if tag[0] == "c" && len(tag) > 1 && tag[1] == to { + hasMatchingCommit = true + break + } + } + if !hasMatchingCommit { + return fmt.Errorf("push rejected: event %s has different tip (expected %s)", eventId, to) + } + foundEvent = true + break + } + if !foundEvent { + return fmt.Errorf("push rejected: event %s not found", eventId) + } + continue + } + + // validate branch pushes + if strings.HasPrefix(ref, "refs/heads/") { + branchName := ref[11:] + // pushing a branch + if commitId, exists := state.Branches[branchName]; exists && to == commitId { + continue + } + // deleting a branch + if _, exists := state.Branches[branchName]; to == zeroRef && !exists { + continue + } + return fmt.Errorf("push unauthorized: ref %s %s->%s does not match state", ref, from, to) + } + + // validate tag pushes + if strings.HasPrefix(ref, "refs/tags/") { + tagName := ref[10:] + // pushing a tag + if commitId, exists := state.Tags[tagName]; exists && to == commitId { + continue + } + // deleting a tag + if _, exists := state.Tags[tagName]; to == zeroRef && !exists { + continue + } + return fmt.Errorf("push unauthorized: ref %s %s->%s does not match state", ref, from, to) + } + } + + return nil +} + +// repoExists checks if a repository has an announcement event (kind 30617) +func (gs *GraspServer) repoExists(pubkey nostr.PubKey, repoName string) bool { + for range gs.Relay.QueryStored(context.Background(), nostr.Filter{ + Kinds: []nostr.Kind{nostr.KindRepositoryAnnouncement}, + Authors: []nostr.PubKey{pubkey}, + Tags: nostr.TagMap{"d": []string{repoName}}, + }) { + return true + } + return false +} + +// newWriteFlusher creates a write flusher for streaming responses +func (gs *GraspServer) newWriteFlusher(w http.ResponseWriter) io.Writer { + return writeFlusher{w.(interface { + io.Writer + http.Flusher + })} +} + +type writeFlusher struct { + wf interface { + io.Writer + http.Flusher + } +} + +func (w writeFlusher) Write(p []byte) (int, error) { + defer w.wf.Flush() + return w.wf.Write(p) +} diff --git a/khatru/grasp/info.go b/khatru/grasp/info.go new file mode 100644 index 0000000..9c8bb00 --- /dev/null +++ b/khatru/grasp/info.go @@ -0,0 +1,104 @@ +package grasp + +import ( + "bytes" + "fmt" + "io" + "net/http" + "os" + "os/exec" + "path/filepath" + "strings" + "syscall" + + "fiatjaf.com/nostr" +) + +// handleInfoRefs handles the git info/refs endpoint +func (gs *GraspServer) handleInfoRefs( + w http.ResponseWriter, + r *http.Request, + pubkey nostr.PubKey, + repoName string, +) { + if !gs.repoExists(pubkey, repoName) { + w.Header().Set("content-type", "text/plain; charset=UTF-8") + w.WriteHeader(404) + fmt.Fprintf(w, "repository announcement event not found during info-refs\n") + return + } + + repoPath := filepath.Join(gs.RepositoryDir, repoName) + serviceName := r.URL.Query().Get("service") + + w.Header().Set("Connection", "Keep-Alive") + w.Header().Set("Cache-Control", "no-cache, max-age=0, must-revalidate") + w.Header().Set("Content-Type", "application/x-"+serviceName+"-advertisement") + + if _, err := os.Stat(repoPath); os.IsNotExist(err) { + // if the repo doesn't exist that's because it wasn't pushed yet, so return an empty response + + // service advertisement header: packet-line with "# service=\n" + serviceLine := fmt.Sprintf("# service=%s\n", serviceName) + // write packet line + length := len(serviceLine) + 4 + fmt.Fprintf(w, "%04x%s", length, serviceLine) + + // flush + w.Write([]byte("0000")) + + // another flush packet to indicate end of refs + w.Write([]byte("0000")) + + return + } + + if err := gs.runInfoRefs(w, r, serviceName, repoPath); err != nil { + gs.Log("error on info-refs rpc: %s\n", err) + return + } +} + +// runInfoRefs executes git-upload-pack with --http-backend-info-refs +func (gs *GraspServer) runInfoRefs(w http.ResponseWriter, r *http.Request, serviceName, repoPath string) error { + cmd := exec.Command(serviceName, "--stateless-rpc", "--http-backend-info-refs", ".") + cmd.SysProcAttr = &syscall.SysProcAttr{Setpgid: true} + cmd.Dir = repoPath + cmd.Env = append(os.Environ(), fmt.Sprintf("GIT_PROTOCOL=%s", r.Header.Get("Git-Protocol"))) + + var stderr bytes.Buffer + cmd.Stderr = &stderr + + stdoutPipe, err := cmd.StdoutPipe() + if err != nil { + return fmt.Errorf("failed to create stdout pipe: %w", err) + } + + // write pack line header only if not git protocol v2 + if !strings.Contains(r.Header.Get("Git-Protocol"), "version=2") { + // packLine + s := "# service=" + serviceName + "\n" + if _, err := fmt.Fprintf(w, "%04x%s", len(s)+4, s); err != nil { + return fmt.Errorf("failed to write pack line: %w", err) + } + + // packFlush + if _, err := fmt.Fprint(w, "0000"); err != nil { + return fmt.Errorf("failed to flush pack: %w", err) + } + } + + if err := cmd.Start(); err != nil { + return fmt.Errorf("failed to start %s: %w, %s", serviceName, err, stderr.String()) + } + + io.Copy(gs.newWriteFlusher(w), stdoutPipe) + stdoutPipe.Close() + + if err := cmd.Wait(); err != nil { + gs.Log("%s failed: %w, stderr: %s", serviceName, err, stderr.String()) + return fmt.Errorf("%s failed: %w, stderr: %s", serviceName, err, stderr.String()) + } + + return nil +} diff --git a/khatru/grasp/read.go b/khatru/grasp/read.go new file mode 100644 index 0000000..2658fac --- /dev/null +++ b/khatru/grasp/read.go @@ -0,0 +1,117 @@ +package grasp + +import ( + "bytes" + "compress/gzip" + "fmt" + "io" + "net/http" + "os" + "os/exec" + "path/filepath" + "syscall" + + "fiatjaf.com/nostr" +) + +func (gs *GraspServer) handleGitUploadPack( + w http.ResponseWriter, + r *http.Request, + pubkey nostr.PubKey, + repoName string, +) { + repoPath := filepath.Join(gs.RepositoryDir, repoName) + + // for upload-pack (pull), check if repository exists + if !gs.repoExists(pubkey, repoName) { + w.Header().Set("content-type", "text/plain; charset=UTF-8") + w.WriteHeader(404) + fmt.Fprintf(w, "repository announcement event not found during upload-pack\n") + return + } + + if gs.OnRead != nil { + reject, msg := gs.OnRead(r.Context(), pubkey, repoName) + if reject { + w.Header().Set("content-type", "text/plain; charset=UTF-8") + w.WriteHeader(403) + fmt.Fprintf(w, "%s\n", msg) + return + } + } + + const expectedContentType = "application/x-git-upload-pack-request" + contentType := r.Header.Get("Content-Type") + if contentType != expectedContentType { + w.Header().Set("content-type", "text/plain; charset=UTF-8") + w.WriteHeader(415) + fmt.Fprintf(w, "expected Content-Type: '%s', but received '%s'\n", expectedContentType, contentType) + return + } + + var bodyReader io.ReadCloser = r.Body + if r.Header.Get("Content-Encoding") == "gzip" { + gzipReader, err := gzip.NewReader(r.Body) + if err != nil { + w.Header().Set("content-type", "text/plain; charset=UTF-8") + w.WriteHeader(500) + fmt.Fprintf(w, "failed to create gzip reader, handler: UploadPack, error: %v\n", err) + return + } + defer gzipReader.Close() + bodyReader = gzipReader + } + + w.Header().Set("Content-Type", "application/x-git-upload-pack-result") + w.Header().Set("Connection", "Keep-Alive") + w.Header().Set("Cache-Control", "no-cache, max-age=0, must-revalidate") + w.WriteHeader(200) + + if err := gs.runUploadPack(w, r, repoPath, bodyReader); err != nil { + w.Header().Set("content-type", "text/plain; charset=UTF-8") + w.WriteHeader(403) + fmt.Fprintf(w, "failed to execute git-upload-pack, handler: UploadPack, error: %v\n", err) + return + } +} + +// runUploadPack executes git-upload-pack for pull operations +func (gs *GraspServer) runUploadPack(w http.ResponseWriter, r *http.Request, repoPath string, bodyReader io.ReadCloser) error { + cmd := exec.Command("git", "upload-pack", "--stateless-rpc", ".") + cmd.SysProcAttr = &syscall.SysProcAttr{Setpgid: true} + cmd.Dir = repoPath + cmd.Env = append(os.Environ(), fmt.Sprintf("GIT_PROTOCOL=%s", r.Header.Get("Git-Protocol"))) + + var stderr bytes.Buffer + cmd.Stderr = &stderr + + stdoutPipe, err := cmd.StdoutPipe() + if err != nil { + return fmt.Errorf("failed to create stdout pipe: %w", err) + } + + stdinPipe, err := cmd.StdinPipe() + if err != nil { + return fmt.Errorf("failed to create stdin pipe: %w", err) + } + + if err := cmd.Start(); err != nil { + return fmt.Errorf("failed to start git-upload-pack: %w", err) + } + + // copy input to stdin + go func() { + defer stdinPipe.Close() + io.Copy(stdinPipe, bodyReader) + }() + + // copy output to response + io.Copy(gs.newWriteFlusher(w), stdoutPipe) + stdoutPipe.Close() + + if err := cmd.Wait(); err != nil { + return fmt.Errorf("git-upload-pack failed: %w, stderr: %s", err, stderr.String()) + } + + return nil +} diff --git a/khatru/grasp/server.go b/khatru/grasp/server.go index 100c35c..d125373 100644 --- a/khatru/grasp/server.go +++ b/khatru/grasp/server.go @@ -1,34 +1,15 @@ package grasp import ( - "bytes" - "compress/gzip" "context" - "errors" "fmt" - "io" "net/http" "os" - "os/exec" - "path/filepath" - "regexp" - "slices" - "strings" - "sync" - "syscall" - "time" "fiatjaf.com/nostr" "fiatjaf.com/nostr/khatru" - "fiatjaf.com/nostr/nip19" - "fiatjaf.com/nostr/nip34" - "github.com/go-git/go-git/v5/plumbing/format/pktline" ) -const zeroRef = "0000000000000000000000000000000000000000" - -var asciiPattern = regexp.MustCompile(`^[\w-.]+$`) - type GraspServer struct { ServiceURL string RepositoryDir string @@ -92,710 +73,3 @@ func New(rl *khatru.Relay, repositoryDir string) *GraspServer { return gs } - -// handleGitRequest validates .git suffix and decodes npub, then calls the handler -func (gs *GraspServer) handleGitRequest( - w http.ResponseWriter, - r *http.Request, - base http.Handler, - handler func(http.ResponseWriter, - *http.Request, - nostr.PubKey, - string, - ), -) { - npub := r.PathValue("npub") - repoWithGit := r.PathValue("repo") - - // validate .git suffix - if !strings.HasSuffix(repoWithGit, ".git") { - base.ServeHTTP(w, r) - return - } - - repoName := strings.TrimSuffix(repoWithGit, ".git") - - // validate repo name - if !asciiPattern.MatchString(repoName) { - http.Error(w, "invalid repository name", 400) - return - } - - // decode npub to pubkey - _, value, err := nip19.Decode(npub) - if err != nil { - http.Error(w, "invalid npub", 400) - return - } - pk, ok := value.(nostr.PubKey) - if !ok { - http.Error(w, "invalid npub", 400) - return - } - - handler(w, r, pk, repoName) -} - -// handleInfoRefs handles the git info/refs endpoint -func (gs *GraspServer) handleInfoRefs( - w http.ResponseWriter, - r *http.Request, - pubkey nostr.PubKey, - repoName string, -) { - if !gs.repoExists(pubkey, repoName) { - w.Header().Set("content-type", "text/plain; charset=UTF-8") - w.WriteHeader(404) - fmt.Fprintf(w, "repository announcement event not found during info-refs\n") - return - } - - repoPath := filepath.Join(gs.RepositoryDir, repoName) - serviceName := r.URL.Query().Get("service") - - w.Header().Set("Connection", "Keep-Alive") - w.Header().Set("Cache-Control", "no-cache, max-age=0, must-revalidate") - w.Header().Set("Content-Type", "application/x-"+serviceName+"-advertisement") - - if _, err := os.Stat(repoPath); os.IsNotExist(err) { - // if the repo doesn't exist that's because it wasn't pushed yet, so return an empty response - - // service advertisement header: packet-line with "# service=\n" - serviceLine := fmt.Sprintf("# service=%s\n", serviceName) - // write packet line - length := len(serviceLine) + 4 - fmt.Fprintf(w, "%04x%s", length, serviceLine) - - // flush - w.Write([]byte("0000")) - - // another flush packet to indicate end of refs - w.Write([]byte("0000")) - - return - } - - if err := gs.runInfoRefs(w, r, serviceName, repoPath); err != nil { - gs.Log("error on info-refs rpc: %s\n", err) - return - } -} - -func (gs *GraspServer) handleGitUploadPack( - w http.ResponseWriter, - r *http.Request, - pubkey nostr.PubKey, - repoName string, -) { - repoPath := filepath.Join(gs.RepositoryDir, repoName) - - // for upload-pack (pull), check if repository exists - if !gs.repoExists(pubkey, repoName) { - w.Header().Set("content-type", "text/plain; charset=UTF-8") - w.WriteHeader(404) - fmt.Fprintf(w, "repository announcement event not found during upload-pack\n") - return - } - - if gs.OnRead != nil { - reject, msg := gs.OnRead(r.Context(), pubkey, repoName) - if reject { - w.Header().Set("content-type", "text/plain; charset=UTF-8") - w.WriteHeader(403) - fmt.Fprintf(w, "%s\n", msg) - return - } - } - - const expectedContentType = "application/x-git-upload-pack-request" - contentType := r.Header.Get("Content-Type") - if contentType != expectedContentType { - w.Header().Set("content-type", "text/plain; charset=UTF-8") - w.WriteHeader(415) - fmt.Fprintf(w, "expected Content-Type: '%s', but received '%s'\n", expectedContentType, contentType) - return - } - - var bodyReader io.ReadCloser = r.Body - if r.Header.Get("Content-Encoding") == "gzip" { - gzipReader, err := gzip.NewReader(r.Body) - if err != nil { - w.Header().Set("content-type", "text/plain; charset=UTF-8") - w.WriteHeader(500) - fmt.Fprintf(w, "failed to create gzip reader, handler: UploadPack, error: %v\n", err) - return - } - defer gzipReader.Close() - bodyReader = gzipReader - } - - w.Header().Set("Content-Type", "application/x-git-upload-pack-result") - w.Header().Set("Connection", "Keep-Alive") - w.Header().Set("Cache-Control", "no-cache, max-age=0, must-revalidate") - w.WriteHeader(200) - - if err := gs.runUploadPack(w, r, repoPath, bodyReader); err != nil { - w.Header().Set("content-type", "text/plain; charset=UTF-8") - w.WriteHeader(403) - fmt.Fprintf(w, "failed to execute git-upload-pack, handler: UploadPack, error: %v\n", err) - return - } -} - -func (gs *GraspServer) handleGitReceivePack( - w http.ResponseWriter, - r *http.Request, - pubkey nostr.PubKey, - repoName string, -) { - // for receive-pack (push), validate authorization via NIP-34 events - body := &bytes.Buffer{} - io.Copy(body, r.Body) - - if err := gs.validatePush(r.Context(), pubkey, repoName, body.Bytes()); err != nil { - w.Header().Set("content-type", "text/plain; charset=UTF-8") - w.WriteHeader(403) - fmt.Fprintf(w, "unauthorized push: %v\n", err) - return - } - - if gs.OnWrite != nil { - reject, msg := gs.OnWrite(r.Context(), pubkey, repoName) - if reject { - w.Header().Set("content-type", "text/plain; charset=UTF-8") - w.WriteHeader(403) - fmt.Fprintf(w, "%s\n", msg) - return - } - } - - repoPath := filepath.Join(gs.RepositoryDir, repoName) - - // initialize git repo if it doesn't exist - if _, err := os.Stat(repoPath); os.IsNotExist(err) { - if err := os.MkdirAll(repoPath, 0755); err != nil { - w.Header().Set("content-type", "text/plain; charset=UTF-8") - w.WriteHeader(500) - fmt.Fprintf(w, "failed to create repository: %s\n", err) - return - } - - cmd := exec.Command("git", "init", "--bare") - cmd.Dir = repoPath - if output, err := cmd.CombinedOutput(); err != nil { - w.Header().Set("content-type", "text/plain; charset=UTF-8") - w.WriteHeader(500) - fmt.Fprintf(w, "failed to initialize repository: %s, output: %s\n", err, string(output)) - return - } - - // disable denyNonFastForwards and denyCurrentBranch to allow force pushes - for _, config := range []struct { - key string - value string - }{ - {"receive.denyNonFastForwards", "false"}, - {"receive.denyCurrentBranch", "updateInstead"}, - {"uploadpack.allowReachableSHA1InWant", "true"}, - {"uploadpack.allowTipSHA1InWant", "true"}, - } { - cmd = exec.Command("git", "config", config.key, config.value) - cmd.Dir = repoPath - if output, err := cmd.CombinedOutput(); err != nil { - w.Header().Set("content-type", "text/plain; charset=UTF-8") - w.WriteHeader(500) - fmt.Fprintf(w, "failed to configure repository with %s=%s: %s, output: %s\n", - config.key, config.value, err, string(output)) - return - } - } - } - - w.Header().Set("Content-Type", "application/x-git-receive-pack-result") - w.Header().Set("Connection", "Keep-Alive") - w.Header().Set("Cache-Control", "no-cache, max-age=0, must-revalidate") - - if err := gs.runReceivePack(w, r, repoPath, io.NopCloser(bytes.NewReader(body.Bytes()))); err != nil { - w.Header().Set("content-type", "text/plain; charset=UTF-8") - w.WriteHeader(403) - fmt.Fprintf(w, "runReceivePack: %v\n", err) - return - } - - // update HEAD per state announcement - if err := gs.updateHEAD(r.Context(), pubkey, repoName, repoPath); err != nil { - w.Header().Set("content-type", "text/plain; charset=UTF-8") - w.WriteHeader(403) - fmt.Fprintf(w, "failed to update HEAD: %v\n", err) - return - } - - // cleanup merged patches - go gs.cleanupMergedPatches(r.Context(), pubkey, repoName, repoPath) -} - -// validatePush checks if a push is authorized via NIP-34 repository state events -func (gs *GraspServer) validatePush( - ctx context.Context, - pubkey nostr.PubKey, - repoName string, - bodyBytes []byte, -) error { - // query for repository state events (kind 30618) - if gs.Relay.QueryStored == nil { - return errors.New("relay has no QueryStored function") - } - - // check state - var state nip34.RepositoryState - for evt := range gs.Relay.QueryStored(ctx, nostr.Filter{ - Kinds: []nostr.Kind{nostr.KindRepositoryState}, - Authors: []nostr.PubKey{pubkey}, - Tags: nostr.TagMap{"d": []string{repoName}}, - Limit: 1, - }) { - state = nip34.ParseRepositoryState(evt) - } - if state.Event.ID == nostr.ZeroID { - return fmt.Errorf("no state found for repository '%s'", repoName) - } - - // get repository announcement to check maintainers - var announcement nip34.Repository - for evt := range gs.Relay.QueryStored(ctx, nostr.Filter{ - Kinds: []nostr.Kind{nostr.KindRepositoryAnnouncement}, - Authors: []nostr.PubKey{pubkey}, - Tags: nostr.TagMap{"d": []string{repoName}}, - Limit: 1, - }) { - announcement = nip34.ParseRepository(evt) - } - if announcement.Event.ID == nostr.ZeroID { - return fmt.Errorf("no announcement found for repository '%s'", repoName) - } - - // ensure pusher is authorized (owner or maintainer) - if pubkey != announcement.PubKey && !slices.Contains(announcement.Maintainers, pubkey) { - return fmt.Errorf("pusher '%s' is not authorized for repository '%s'", pubkey, repoName) - } - - // parse pktline to extract and validate all push refs - pkt := pktline.NewScanner(bytes.NewReader(bodyBytes)) - for pkt.Scan() { - if err := pkt.Err(); err != nil { - return fmt.Errorf("invalid pkt: %v", err) - } - line := string(pkt.Bytes()) - if len(line) < 40 { - continue - } - - spl := strings.Split(line, " ") - from := spl[0] - to := spl[1] - ref := strings.TrimRight(spl[2], "\x00") - - // handle refs/nostr/ pushes - if strings.HasPrefix(ref, "refs/nostr/") { - // query for the event - eventId := ref[11:] - id, err := nostr.IDFromHex(eventId) - if err != nil { - return fmt.Errorf("push rejected: invalid event id %s", eventId) - } - var foundEvent bool - for evt := range gs.Relay.QueryStored(ctx, nostr.Filter{ - IDs: []nostr.ID{id}, - }) { - // check if event has a "c" tag matching the commit - hasMatchingCommit := false - for _, tag := range evt.Tags { - if tag[0] == "c" && len(tag) > 1 && tag[1] == to { - hasMatchingCommit = true - break - } - } - if !hasMatchingCommit { - return fmt.Errorf("push rejected: event %s has different tip (expected %s)", eventId, to) - } - foundEvent = true - break - } - if !foundEvent { - return fmt.Errorf("push rejected: event %s not found", eventId) - } - continue - } - - // validate branch pushes - if strings.HasPrefix(ref, "refs/heads/") { - branchName := ref[11:] - // pushing a branch - if commitId, exists := state.Branches[branchName]; exists && to == commitId { - continue - } - // deleting a branch - if _, exists := state.Branches[branchName]; to == zeroRef && !exists { - continue - } - return fmt.Errorf("push unauthorized: ref %s %s->%s does not match state", ref, from, to) - } - - // validate tag pushes - if strings.HasPrefix(ref, "refs/tags/") { - tagName := ref[10:] - // pushing a tag - if commitId, exists := state.Tags[tagName]; exists && to == commitId { - continue - } - // deleting a tag - if _, exists := state.Tags[tagName]; to == zeroRef && !exists { - continue - } - return fmt.Errorf("push unauthorized: ref %s %s->%s does not match state", ref, from, to) - } - } - - return nil -} - -// repoExists checks if a repository has an announcement event (kind 30617) -func (gs *GraspServer) repoExists(pubkey nostr.PubKey, repoName string) bool { - for range gs.Relay.QueryStored(context.Background(), nostr.Filter{ - Kinds: []nostr.Kind{nostr.KindRepositoryAnnouncement}, - Authors: []nostr.PubKey{pubkey}, - Tags: nostr.TagMap{"d": []string{repoName}}, - }) { - return true - } - return false -} - -// runInfoRefs executes git-upload-pack with --http-backend-info-refs -func (gs *GraspServer) runInfoRefs(w http.ResponseWriter, r *http.Request, serviceName, repoPath string) error { - cmd := exec.Command(serviceName, "--stateless-rpc", "--http-backend-info-refs", ".") - cmd.SysProcAttr = &syscall.SysProcAttr{Setpgid: true} - cmd.Dir = repoPath - cmd.Env = append(os.Environ(), fmt.Sprintf("GIT_PROTOCOL=%s", r.Header.Get("Git-Protocol"))) - - var stderr bytes.Buffer - cmd.Stderr = &stderr - - stdoutPipe, err := cmd.StdoutPipe() - if err != nil { - return fmt.Errorf("failed to create stdout pipe: %w", err) - } - - // write pack line header only if not git protocol v2 - if !strings.Contains(r.Header.Get("Git-Protocol"), "version=2") { - // packLine - s := "# service=" + serviceName + "\n" - if _, err := fmt.Fprintf(w, "%04x%s", len(s)+4, s); err != nil { - return fmt.Errorf("failed to write pack line: %w", err) - } - - // packFlush - if _, err := fmt.Fprint(w, "0000"); err != nil { - return fmt.Errorf("failed to flush pack: %w", err) - } - } - - if err := cmd.Start(); err != nil { - return fmt.Errorf("failed to start %s: %w, %s", serviceName, err, stderr.String()) - } - - io.Copy(gs.newWriteFlusher(w), stdoutPipe) - stdoutPipe.Close() - - if err := cmd.Wait(); err != nil { - gs.Log("%s failed: %w, stderr: %s", serviceName, err, stderr.String()) - return fmt.Errorf("%s failed: %w, stderr: %s", serviceName, err, stderr.String()) - } - - return nil -} - -// runUploadPack executes git-upload-pack for pull operations -func (gs *GraspServer) runUploadPack(w http.ResponseWriter, r *http.Request, repoPath string, bodyReader io.ReadCloser) error { - cmd := exec.Command("git", "upload-pack", "--stateless-rpc", ".") - cmd.SysProcAttr = &syscall.SysProcAttr{Setpgid: true} - cmd.Dir = repoPath - cmd.Env = append(os.Environ(), fmt.Sprintf("GIT_PROTOCOL=%s", r.Header.Get("Git-Protocol"))) - - var stderr bytes.Buffer - cmd.Stderr = &stderr - - stdoutPipe, err := cmd.StdoutPipe() - if err != nil { - return fmt.Errorf("failed to create stdout pipe: %w", err) - } - - stdinPipe, err := cmd.StdinPipe() - if err != nil { - return fmt.Errorf("failed to create stdin pipe: %w", err) - } - - if err := cmd.Start(); err != nil { - return fmt.Errorf("failed to start git-upload-pack: %w", err) - } - - // copy input to stdin - go func() { - defer stdinPipe.Close() - io.Copy(stdinPipe, bodyReader) - }() - - // copy output to response - io.Copy(gs.newWriteFlusher(w), stdoutPipe) - stdoutPipe.Close() - - if err := cmd.Wait(); err != nil { - return fmt.Errorf("git-upload-pack failed: %w, stderr: %s", err, stderr.String()) - } - - return nil -} - -// runReceivePack executes git-receive-pack for push operations -func (gs *GraspServer) runReceivePack(w http.ResponseWriter, r *http.Request, repoPath string, bodyReader io.ReadCloser) error { - cmd := exec.Command("git", "receive-pack", "--stateless-rpc", ".") - cmd.SysProcAttr = &syscall.SysProcAttr{Setpgid: true} - cmd.Dir = repoPath - cmd.Env = append(os.Environ(), fmt.Sprintf("GIT_PROTOCOL=%s", r.Header.Get("Git-Protocol"))) - - var stderr bytes.Buffer - cmd.Stderr = &stderr - - stdoutPipe, err := cmd.StdoutPipe() - if err != nil { - return fmt.Errorf("failed to create stdout pipe: %w", err) - } - - stdinPipe, err := cmd.StdinPipe() - if err != nil { - return fmt.Errorf("failed to create stdin pipe: %w", err) - } - - if err := cmd.Start(); err != nil { - return fmt.Errorf("failed to start git-receive-pack: %w", err) - } - - wg := sync.WaitGroup{} - - // copy input to stdin - wg.Go(func() { - defer stdinPipe.Close() - if _, err := io.Copy(stdinPipe, bodyReader); err != nil { - gs.Log("failed to copy to stdin pipe: %s", err) - } - }) - - // copy output to response - wg.Go(func() { - defer stdoutPipe.Close() - if _, err := io.Copy(gs.newWriteFlusher(w), stdoutPipe); err != nil { - gs.Log("failed to copy to write flusher: %s", err) - } - }) - - wg.Wait() - - if err := cmd.Wait(); err != nil { - return fmt.Errorf("git-receive-pack failed: %w, stderr: %s", err, stderr.String()) - } - - return nil -} - -// updateHEAD updates the repository HEAD based on the latest state announcement -func (gs *GraspServer) updateHEAD(ctx context.Context, pubkey nostr.PubKey, repoName, repoPath string) error { - if gs.Relay.QueryStored == nil { - return fmt.Errorf("no QueryStored function") - } - - // query for the latest state event - var latestState *nip34.RepositoryState - for evt := range gs.Relay.QueryStored(ctx, nostr.Filter{ - Kinds: []nostr.Kind{nostr.KindRepositoryState}, - Authors: []nostr.PubKey{pubkey}, - Tags: nostr.TagMap{"d": []string{repoName}}, - Limit: 1, - }) { - state := nip34.ParseRepositoryState(evt) - latestState = &state - break - } - - if latestState == nil || latestState.HEAD == "" { - // no state or no HEAD specified - return nil - } - - // verify the HEAD branch exists in the state - if _, exists := latestState.Branches[latestState.HEAD]; !exists { - return fmt.Errorf("HEAD branch %s not found in state", latestState.HEAD) - } - - // update HEAD using git symbolic-ref - cmd := exec.Command("git", "symbolic-ref", "HEAD", "refs/heads/"+latestState.HEAD) - cmd.Dir = repoPath - if output, err := cmd.CombinedOutput(); err != nil { - return fmt.Errorf("failed to update HEAD: %w, output: %s", err, string(output)) - } - return nil -} - -// cleanupMergedPatches removes refs/nostr/ refs that have been merged into branches -func (gs *GraspServer) cleanupMergedPatches(ctx context.Context, pubkey nostr.PubKey, repoName, repoPath string) { - // use background context since request context will be cancelled - ctx = context.Background() - - // wait 20 minutes before cleanup to allow events to propagate - time.Sleep(20 * time.Minute) - - if gs.Relay.QueryStored == nil { - return - } - - // get current state to know which branches exist - var state *nip34.RepositoryState - for evt := range gs.Relay.QueryStored(ctx, nostr.Filter{ - Kinds: []nostr.Kind{nostr.KindRepositoryState}, - Authors: []nostr.PubKey{pubkey}, - Tags: nostr.TagMap{"d": []string{repoName}}, - Limit: 1, - }) { - parsed := nip34.ParseRepositoryState(evt) - state = &parsed - break - } - - if state == nil { - return - } - - // list all refs/nostr/* refs - cmd := exec.Command("git", "for-each-ref", "--format=%(refname)", "refs/nostr") - cmd.Dir = repoPath - output, err := cmd.Output() - if err != nil { - // no refs/nostr refs, nothing to clean up - return - } - - refs := strings.Split(strings.TrimSpace(string(output)), "\n") - for _, ref := range refs { - if ref == "" { - continue - } - - eventId := strings.TrimPrefix(ref, "refs/nostr/") - id, err := nostr.IDFromHex(eventId) - if err != nil { - return - } - - // check if there's still a valid patch event with a "c" tag referencing this commit - hasValidEvent := false - for evt := range gs.Relay.QueryStored(ctx, nostr.Filter{ - IDs: []nostr.ID{id}, - }) { - // check if event has a "c" tag - for _, tag := range evt.Tags { - if tag[0] == "c" && len(tag) > 1 { - hasValidEvent = true - break - } - } - break - } - - if !hasValidEvent { - // no valid event, delete the ref - cmd := exec.Command("git", "update-ref", "-d", ref) - cmd.Dir = repoPath - if err := cmd.Run(); err != nil { - gs.Log("failed to delete ref %s: %s\n", ref, err) - } else { - gs.Log("deleted ref %s (no corresponding event)\n", ref) - } - continue - } - - // check if the commit is merged into any branch - for branchName, commitId := range state.Branches { - // get the commit ID for this ref - cmd := exec.Command("git", "rev-parse", ref) - cmd.Dir = repoPath - refCommit, err := cmd.Output() - if err != nil { - continue - } - - // check if ref commit is ancestor of branch head - cmd = exec.Command("git", "merge-base", "--is-ancestor", strings.TrimSpace(string(refCommit)), commitId) - cmd.Dir = repoPath - if err := cmd.Run(); err == nil { - // it's merged! delete the ref - cmd := exec.Command("git", "update-ref", "-d", ref) - cmd.Dir = repoPath - if err := cmd.Run(); err != nil { - gs.Log("failed to delete ref %s: %s\n", ref, err) - } else { - gs.Log("deleted ref %s (merged into %s)\n", ref, branchName) - } - break - } - } - } -} - -// serveRepoPage serves a webpage for the repository -func (gs *GraspServer) serveRepoPage(w http.ResponseWriter, r *http.Request, npub, repoName string) { - w.Header().Set("Content-Type", "text/html") - html := fmt.Sprintf(` - - - %s/%s - NIP-34 Git Repository - - - -

Repository: %s/%s

-
-

This is a NIP-34 git repository served over Nostr.

-
-

Clone this repository

-

Use a git-nostr client to clone:

- 
git clone %s/%s/%s.git
-

Browse

-

Use a git-nostr web client or Nostr client to browse this repository.

- -`, npub, repoName, npub, repoName, r.Host, npub, repoName) - fmt.Fprint(w, html) -} - -// newWriteFlusher creates a write flusher for streaming responses -func (gs *GraspServer) newWriteFlusher(w http.ResponseWriter) io.Writer { - return writeFlusher{w.(interface { - io.Writer - http.Flusher - })} -} - -type writeFlusher struct { - wf interface { - io.Writer - http.Flusher - } -} - -func (w writeFlusher) Write(p []byte) (int, error) { - defer w.wf.Flush() - return w.wf.Write(p) -} diff --git a/khatru/grasp/write.go b/khatru/grasp/write.go new file mode 100644 index 0000000..c1a0297 --- /dev/null +++ b/khatru/grasp/write.go @@ -0,0 +1,305 @@ +package grasp + +import ( + "bytes" + "context" + "fmt" + "io" + "net/http" + "os" + "os/exec" + "path/filepath" + "strings" + "sync" + "syscall" + "time" + + "fiatjaf.com/nostr" + "fiatjaf.com/nostr/nip34" +) + +func (gs *GraspServer) handleGitReceivePack( + w http.ResponseWriter, + r *http.Request, + pubkey nostr.PubKey, + repoName string, +) { + // for receive-pack (push), validate authorization via NIP-34 events + body := &bytes.Buffer{} + io.Copy(body, r.Body) + + if err := gs.validatePush(r.Context(), pubkey, repoName, body.Bytes()); err != nil { + w.Header().Set("content-type", "text/plain; charset=UTF-8") + w.WriteHeader(403) + fmt.Fprintf(w, "unauthorized push: %v\n", err) + return + } + + if gs.OnWrite != nil { + reject, msg := gs.OnWrite(r.Context(), pubkey, repoName) + if reject { + w.Header().Set("content-type", "text/plain; charset=UTF-8") + w.WriteHeader(403) + fmt.Fprintf(w, "%s\n", msg) + return + } + } + + repoPath := filepath.Join(gs.RepositoryDir, repoName) + + // initialize git repo if it doesn't exist + if _, err := os.Stat(repoPath); os.IsNotExist(err) { + if err := os.MkdirAll(repoPath, 0755); err != nil { + w.Header().Set("content-type", "text/plain; charset=UTF-8") + w.WriteHeader(500) + fmt.Fprintf(w, "failed to create repository: %s\n", err) + return + } + + cmd := exec.Command("git", "init", "--bare") + cmd.Dir = repoPath + if output, err := cmd.CombinedOutput(); err != nil { + w.Header().Set("content-type", "text/plain; charset=UTF-8") + w.WriteHeader(500) + fmt.Fprintf(w, "failed to initialize repository: %s, output: %s\n", err, string(output)) + return + } + + // disable denyNonFastForwards and denyCurrentBranch to allow force pushes + for _, config := range []struct { + key string + value string + }{ + {"receive.denyNonFastForwards", "false"}, + {"receive.denyCurrentBranch", "updateInstead"}, + {"uploadpack.allowReachableSHA1InWant", "true"}, + {"uploadpack.allowTipSHA1InWant", "true"}, + } { + cmd = exec.Command("git", "config", config.key, config.value) + cmd.Dir = repoPath + if output, err := cmd.CombinedOutput(); err != nil { + w.Header().Set("content-type", "text/plain; charset=UTF-8") + w.WriteHeader(500) + fmt.Fprintf(w, "failed to configure repository with %s=%s: %s, output: %s\n", + config.key, config.value, err, string(output)) + return + } + } + } + + w.Header().Set("Content-Type", "application/x-git-receive-pack-result") + w.Header().Set("Connection", "Keep-Alive") + w.Header().Set("Cache-Control", "no-cache, max-age=0, must-revalidate") + + if err := gs.runReceivePack(w, r, repoPath, io.NopCloser(bytes.NewReader(body.Bytes()))); err != nil { + w.Header().Set("content-type", "text/plain; charset=UTF-8") + w.WriteHeader(403) + fmt.Fprintf(w, "runReceivePack: %v\n", err) + return + } + + // update HEAD per state announcement + if err := gs.updateHEAD(r.Context(), pubkey, repoName, repoPath); err != nil { + w.Header().Set("content-type", "text/plain; charset=UTF-8") + w.WriteHeader(403) + fmt.Fprintf(w, "failed to update HEAD: %v\n", err) + return + } + + // cleanup merged patches + go gs.cleanupMergedPatches(r.Context(), pubkey, repoName, repoPath) +} + +// runReceivePack executes git-receive-pack for push operations +func (gs *GraspServer) runReceivePack(w http.ResponseWriter, r *http.Request, repoPath string, bodyReader io.ReadCloser) error { + cmd := exec.Command("git", "receive-pack", "--stateless-rpc", ".") + cmd.SysProcAttr = &syscall.SysProcAttr{Setpgid: true} + cmd.Dir = repoPath + cmd.Env = append(os.Environ(), fmt.Sprintf("GIT_PROTOCOL=%s", r.Header.Get("Git-Protocol"))) + + var stderr bytes.Buffer + cmd.Stderr = &stderr + + stdoutPipe, err := cmd.StdoutPipe() + if err != nil { + return fmt.Errorf("failed to create stdout pipe: %w", err) + } + + stdinPipe, err := cmd.StdinPipe() + if err != nil { + return fmt.Errorf("failed to create stdin pipe: %w", err) + } + + if err := cmd.Start(); err != nil { + return fmt.Errorf("failed to start git-receive-pack: %w", err) + } + + wg := sync.WaitGroup{} + + // copy input to stdin + wg.Go(func() { + defer stdinPipe.Close() + if _, err := io.Copy(stdinPipe, bodyReader); err != nil { + gs.Log("failed to copy to stdin pipe: %s", err) + } + }) + + // copy output to response + wg.Go(func() { + defer stdoutPipe.Close() + if _, err := io.Copy(gs.newWriteFlusher(w), stdoutPipe); err != nil { + gs.Log("failed to copy to write flusher: %s", err) + } + }) + + wg.Wait() + + if err := cmd.Wait(); err != nil { + return fmt.Errorf("git-receive-pack failed: %w, stderr: %s", err, stderr.String()) + } + + return nil +} + +// updateHEAD updates the repository HEAD based on the latest state announcement +func (gs *GraspServer) updateHEAD(ctx context.Context, pubkey nostr.PubKey, repoName, repoPath string) error { + if gs.Relay.QueryStored == nil { + return fmt.Errorf("no QueryStored function") + } + + // query for the latest state event + var latestState *nip34.RepositoryState + for evt := range gs.Relay.QueryStored(ctx, nostr.Filter{ + Kinds: []nostr.Kind{nostr.KindRepositoryState}, + Authors: []nostr.PubKey{pubkey}, + Tags: nostr.TagMap{"d": []string{repoName}}, + Limit: 1, + }) { + state := nip34.ParseRepositoryState(evt) + latestState = &state + break + } + + if latestState == nil || latestState.HEAD == "" { + // no state or no HEAD specified + return nil + } + + // verify the HEAD branch exists in the state + if _, exists := latestState.Branches[latestState.HEAD]; !exists { + return fmt.Errorf("HEAD branch %s not found in state", latestState.HEAD) + } + + // update HEAD using git symbolic-ref + cmd := exec.Command("git", "symbolic-ref", "HEAD", "refs/heads/"+latestState.HEAD) + cmd.Dir = repoPath + if output, err := cmd.CombinedOutput(); err != nil { + return fmt.Errorf("failed to update HEAD: %w, output: %s", err, string(output)) + } + return nil +} + +// cleanupMergedPatches removes refs/nostr/ refs that have been merged into branches +func (gs *GraspServer) cleanupMergedPatches(ctx context.Context, pubkey nostr.PubKey, repoName, repoPath string) { + // use background context since request context will be cancelled + ctx = context.Background() + + // wait 20 minutes before cleanup to allow events to propagate + time.Sleep(20 * time.Minute) + + if gs.Relay.QueryStored == nil { + return + } + + // get current state to know which branches exist + var state *nip34.RepositoryState + for evt := range gs.Relay.QueryStored(ctx, nostr.Filter{ + Kinds: []nostr.Kind{nostr.KindRepositoryState}, + Authors: []nostr.PubKey{pubkey}, + Tags: nostr.TagMap{"d": []string{repoName}}, + Limit: 1, + }) { + parsed := nip34.ParseRepositoryState(evt) + state = &parsed + break + } + + if state == nil { + return + } + + // list all refs/nostr/* refs + cmd := exec.Command("git", "for-each-ref", "--format=%(refname)", "refs/nostr") + cmd.Dir = repoPath + output, err := cmd.Output() + if err != nil { + // no refs/nostr refs, nothing to clean up + return + } + + refs := strings.Split(strings.TrimSpace(string(output)), "\n") + for _, ref := range refs { + if ref == "" { + continue + } + + eventId := strings.TrimPrefix(ref, "refs/nostr/") + id, err := nostr.IDFromHex(eventId) + if err != nil { + return + } + + // check if there's still a valid patch event with a "c" tag referencing this commit + hasValidEvent := false + for evt := range gs.Relay.QueryStored(ctx, nostr.Filter{ + IDs: []nostr.ID{id}, + }) { + // check if event has a "c" tag + for _, tag := range evt.Tags { + if tag[0] == "c" && len(tag) > 1 { + hasValidEvent = true + break + } + } + break + } + + if !hasValidEvent { + // no valid event, delete the ref + cmd := exec.Command("git", "update-ref", "-d", ref) + cmd.Dir = repoPath + if err := cmd.Run(); err != nil { + gs.Log("failed to delete ref %s: %s\n", ref, err) + } else { + gs.Log("deleted ref %s (no corresponding event)\n", ref) + } + continue + } + + // check if the commit is merged into any branch + for branchName, commitId := range state.Branches { + // get the commit ID for this ref + cmd := exec.Command("git", "rev-parse", ref) + cmd.Dir = repoPath + refCommit, err := cmd.Output() + if err != nil { + continue + } + + // check if ref commit is ancestor of branch head + cmd = exec.Command("git", "merge-base", "--is-ancestor", strings.TrimSpace(string(refCommit)), commitId) + cmd.Dir = repoPath + if err := cmd.Run(); err == nil { + // it's merged! delete the ref + cmd := exec.Command("git", "update-ref", "-d", ref) + cmd.Dir = repoPath + if err := cmd.Run(); err != nil { + gs.Log("failed to delete ref %s: %s\n", ref, err) + } else { + gs.Log("deleted ref %s (merged into %s)\n", ref, branchName) + } + break + } + } + } +}