mugit/internal/handlers/git.go (view raw)
Oleksandr Smirnov
Oleksandr Smirnov
olexsmir@gmail.com fix: limit upload-pack request body to 5 MB, 1 month ago
olexsmir@gmail.com fix: limit upload-pack request body to 5 MB, 1 month ago
| 1 | package handlers |
| 2 | |
| 3 | import ( |
| 4 | "compress/gzip" |
| 5 | "fmt" |
| 6 | "io" |
| 7 | "log/slog" |
| 8 | "net/http" |
| 9 | |
| 10 | "olexsmir.xyz/mugit/internal/git" |
| 11 | ) |
| 12 | |
| 13 | func (h *handlers) infoRefsHandler(w http.ResponseWriter, r *http.Request) { |
| 14 | repo, err := h.openPublicRepo(r.PathValue("name"), "") |
| 15 | if err != nil { |
| 16 | h.gitError(w, http.StatusNotFound, "repository not found") |
| 17 | return |
| 18 | } |
| 19 | |
| 20 | service := r.URL.Query().Get("service") |
| 21 | gitProtocol := r.Header.Get("Git-Protocol") |
| 22 | switch service { |
| 23 | case "git-upload-pack": |
| 24 | w.Header().Set("Content-Type", "application/x-git-upload-pack-advertisement") |
| 25 | w.Header().Set("Connection", "Keep-Alive") |
| 26 | w.Header().Set("Cache-Control", "no-cache, max-age=0, must-revalidate") |
| 27 | |
| 28 | w.WriteHeader(http.StatusOK) |
| 29 | if err := repo.InfoRefs(r.Context(), gitProtocol, w); err != nil { |
| 30 | _ = git.PackError(w, err.Error()) |
| 31 | slog.Error("git: info/refs", "err", err) |
| 32 | return |
| 33 | } |
| 34 | |
| 35 | case "git-receive-pack": |
| 36 | h.receivePackHandler(w, r) |
| 37 | |
| 38 | default: |
| 39 | h.gitError(w, http.StatusBadRequest, "service unsupported") |
| 40 | } |
| 41 | } |
| 42 | |
| 43 | const uploadPackExpectedContentType = "application/x-git-upload-pack-request" |
| 44 | |
| 45 | func (h *handlers) uploadPackHandler(w http.ResponseWriter, r *http.Request) { |
| 46 | gitProtocol := r.Header.Get("Git-Protocol") |
| 47 | repo, err := h.openPublicRepo(r.PathValue("name"), "") |
| 48 | if err != nil { |
| 49 | h.gitError(w, http.StatusNotFound, "repository not found") |
| 50 | return |
| 51 | } |
| 52 | |
| 53 | contentType := r.Header.Get("Content-Type") |
| 54 | if contentType != uploadPackExpectedContentType { |
| 55 | h.gitError(w, http.StatusUnsupportedMediaType, "provided content type is not supported") |
| 56 | return |
| 57 | } |
| 58 | |
| 59 | r.Body = http.MaxBytesReader(w, r.Body, 5<<20) // 5 MB limit |
| 60 | |
| 61 | bodyReader := r.Body |
| 62 | if r.Header.Get("Content-Encoding") == "gzip" { |
| 63 | gzipReader, err := gzip.NewReader(r.Body) |
| 64 | if err != nil { |
| 65 | h.gitError(w, http.StatusInternalServerError, err.Error()) |
| 66 | slog.Error("git: failed to create gzip reader", "err", err) |
| 67 | return |
| 68 | } |
| 69 | defer func() { _ = gzipReader.Close() }() |
| 70 | bodyReader = gzipReader |
| 71 | } |
| 72 | |
| 73 | w.Header().Set("Content-Type", "application/x-git-upload-pack-result") |
| 74 | w.Header().Set("Connection", "Keep-Alive") |
| 75 | w.Header().Set("Cache-Control", "no-cache, max-age=0, must-revalidate") |
| 76 | |
| 77 | w.WriteHeader(http.StatusOK) |
| 78 | if err := repo.UploadPack(r.Context(), true, gitProtocol, bodyReader, newFlushWriter(w)); err != nil { |
| 79 | _ = git.PackError(w, err.Error()) |
| 80 | slog.Error("git: upload-pack", "err", err) |
| 81 | return |
| 82 | } |
| 83 | } |
| 84 | |
| 85 | func (h *handlers) receivePackHandler(w http.ResponseWriter, _ *http.Request) { |
| 86 | h.gitError(w, http.StatusForbidden, "pushes are only supported over ssh") |
| 87 | } |
| 88 | |
| 89 | func (h *handlers) archiveHandler(w http.ResponseWriter, r *http.Request) { |
| 90 | name := r.PathValue("name") |
| 91 | ref := h.parseRef(r.PathValue("ref")) |
| 92 | |
| 93 | repo, err := h.openPublicRepo(name, ref) |
| 94 | if err != nil { |
| 95 | h.write404(w, r.URL.Path, err) |
| 96 | return |
| 97 | } |
| 98 | |
| 99 | filename := fmt.Sprintf("%s-%s.tar.gz", name, ref) |
| 100 | w.Header().Set("Content-Disposition", fmt.Sprintf("attachment; filename=%q", filename)) |
| 101 | w.Header().Set("Content-Type", "application/gzip") |
| 102 | w.WriteHeader(http.StatusOK) |
| 103 | |
| 104 | if err := repo.ArchiveTar(r.Context(), ref, w); err != nil { |
| 105 | slog.Error("git: archive", "ref", ref, "err", err) |
| 106 | return |
| 107 | } |
| 108 | } |
| 109 | |
| 110 | func (h *handlers) gitError(w http.ResponseWriter, code int, msg string) { |
| 111 | w.Header().Set("content-type", "text/plain; charset=UTF-8") |
| 112 | w.WriteHeader(code) |
| 113 | _, _ = fmt.Fprintf(w, "%s\n", msg) |
| 114 | } |
| 115 | |
| 116 | func (h *handlers) openPublicRepo(name, ref string) (*git.Repo, error) { |
| 117 | name = git.ResolveName(name) |
| 118 | path, err := git.ResolvePath(h.c.Repo.Dir, name) |
| 119 | if err != nil { |
| 120 | return nil, err |
| 121 | } |
| 122 | return git.OpenPublic(path, ref) |
| 123 | } |
| 124 | |
| 125 | type flushWriter struct { |
| 126 | w io.Writer |
| 127 | f http.Flusher |
| 128 | } |
| 129 | |
| 130 | func newFlushWriter(w http.ResponseWriter) io.Writer { |
| 131 | f, _ := w.(http.Flusher) |
| 132 | return &flushWriter{w: w, f: f} |
| 133 | } |
| 134 | |
| 135 | func (fw *flushWriter) Write(p []byte) (int, error) { |
| 136 | n, err := fw.w.Write(p) |
| 137 | if fw.f != nil { |
| 138 | fw.f.Flush() |
| 139 | } |
| 140 | return n, err |
| 141 | } |