ui-snapshot.c

   1 /* ui-snapshot.c: generate snapshot of a commit
   2  *
   3  * Copyright (C) 2006-2014 cgit Development Team <cgit@lists.zx2c4.com>
   4  *
   5  * Licensed under GNU General Public License v2
   6  *   (see COPYING for full license text)
   7  */
   8
   9 #include "cgit.h"
  10 #include "ui-snapshot.h"
  11 #include "html.h"
  12 #include "ui-shared.h"
  13
  14 static int write_archive_type(const char *format, const char *hex, const char *prefix)
  15 {
  16         struct argv_array argv = ARGV_ARRAY_INIT;
  17         const char **nargv;
  18         int result;
  19         argv_array_push(&argv, "snapshot");
  20         argv_array_push(&argv, format);
  21         if (prefix) {
  22                 struct strbuf buf = STRBUF_INIT;
  23                 strbuf_addstr(&buf, prefix);
  24                 strbuf_addch(&buf, '/');
  25                 argv_array_push(&argv, "--prefix");
  26                 argv_array_push(&argv, buf.buf);
  27                 strbuf_release(&buf);
  28         }
  29         argv_array_push(&argv, hex);
  30         /*
  31          * Now we need to copy the pointers to arguments into a new
  32          * structure because write_archive will rearrange its arguments
  33          * which may result in duplicated/missing entries causing leaks
  34          * or double-frees in argv_array_clear.
  35          */
  36         nargv = xmalloc(sizeof(char *) * (argv.argc + 1));
  37         /* argv_array guarantees a trailing NULL entry. */
  38         memcpy(nargv, argv.argv, sizeof(char *) * (argv.argc + 1));
  39
  40         result = write_archive(argv.argc, nargv, NULL, the_repository, NULL, 0);
  41         argv_array_clear(&argv);
  42         free(nargv);
  43         return result;
  44 }
  45
  46 static int write_tar_archive(const char *hex, const char *prefix)
  47 {
  48         return write_archive_type("--format=tar", hex, prefix);
  49 }
  50
  51 static int write_zip_archive(const char *hex, const char *prefix)
  52 {
  53         return write_archive_type("--format=zip", hex, prefix);
  54 }
  55
  56 static int write_compressed_tar_archive(const char *hex,
  57                                         const char *prefix,
  58                                         char *filter_argv[])
  59 {
  60         int rv;
  61         struct cgit_exec_filter f;
  62         cgit_exec_filter_init(&f, filter_argv[0], filter_argv);
  63
  64         cgit_open_filter(&f.base);
  65         rv = write_tar_archive(hex, prefix);
  66         cgit_close_filter(&f.base);
  67         return rv;
  68 }
  69
  70 static int write_tar_gzip_archive(const char *hex, const char *prefix)
  71 {
  72         char *argv[] = { "gzip", "-n", NULL };
  73         return write_compressed_tar_archive(hex, prefix, argv);
  74 }
  75
  76 static int write_tar_bzip2_archive(const char *hex, const char *prefix)
  77 {
  78         char *argv[] = { "bzip2", NULL };
  79         return write_compressed_tar_archive(hex, prefix, argv);
  80 }
  81
  82 static int write_tar_lzip_archive(const char *hex, const char *prefix)
  83 {
  84         char *argv[] = { "lzip", NULL };
  85         return write_compressed_tar_archive(hex, prefix, argv);
  86 }
  87
  88 static int write_tar_xz_archive(const char *hex, const char *prefix)
  89 {
  90         char *argv[] = { "xz", NULL };
  91         return write_compressed_tar_archive(hex, prefix, argv);
  92 }
  93
  94 const struct cgit_snapshot_format cgit_snapshot_formats[] = {
  95         /* .tar must remain the 0 index */
  96         { ".tar",       "application/x-tar",    write_tar_archive       },
  97         { ".tar.gz",    "application/x-gzip",   write_tar_gzip_archive  },
  98         { ".tar.bz2",   "application/x-bzip2",  write_tar_bzip2_archive },
  99         { ".tar.lz",    "application/x-lzip",   write_tar_lzip_archive  },
 100         { ".tar.xz",    "application/x-xz",     write_tar_xz_archive    },
 101         { ".zip",       "application/x-zip",    write_zip_archive       },
 102         { NULL }
 103 };
 104
 105 static struct notes_tree snapshot_sig_notes[ARRAY_SIZE(cgit_snapshot_formats)];
 106
 107 const struct object_id *cgit_snapshot_get_sig(const char *ref,
 108                                               const struct cgit_snapshot_format *f)
 109 {
 110         struct notes_tree *tree;
 111         struct object_id oid;
 112
 113         if (get_oid(ref, &oid))
 114                 return NULL;
 115
 116         tree = &snapshot_sig_notes[f - &cgit_snapshot_formats[0]];
 117         if (!tree->initialized) {
 118                 struct strbuf notes_ref = STRBUF_INIT;
 119
 120                 strbuf_addf(&notes_ref, "refs/notes/signatures/%s",
 121                             f->suffix + 1);
 122
 123                 init_notes(tree, notes_ref.buf, combine_notes_ignore, 0);
 124                 strbuf_release(&notes_ref);
 125         }
 126
 127         return get_note(tree, &oid);
 128 }
 129
 130 static const struct cgit_snapshot_format *get_format(const char *filename)
 131 {
 132         const struct cgit_snapshot_format *fmt;
 133
 134         for (fmt = cgit_snapshot_formats; fmt->suffix; fmt++) {
 135                 if (ends_with(filename, fmt->suffix))
 136                         return fmt;
 137         }
 138         return NULL;
 139 }
 140
 141 const unsigned cgit_snapshot_format_bit(const struct cgit_snapshot_format *f)
 142 {
 143         return BIT(f - &cgit_snapshot_formats[0]);
 144 }
 145
 146 static int make_snapshot(const struct cgit_snapshot_format *format,
 147                          const char *hex, const char *prefix,
 148                          const char *filename)
 149 {
 150         struct object_id oid;
 151
 152         if (get_oid(hex, &oid)) {
 153                 cgit_print_error_page(404, "Not found",
 154                                 "Bad object id: %s", hex);
 155                 return 1;
 156         }
 157         if (!lookup_commit_reference(the_repository, &oid)) {
 158                 cgit_print_error_page(400, "Bad request",
 159                                 "Not a commit reference: %s", hex);
 160                 return 1;
 161         }
 162         ctx.page.etag = oid_to_hex(&oid);
 163         ctx.page.mimetype = xstrdup(format->mimetype);
 164         ctx.page.filename = xstrdup(filename);
 165         cgit_print_http_headers();
 166         init_archivers();
 167         format->write_func(hex, prefix);
 168         return 0;
 169 }
 170
 171 static int write_sig(const struct cgit_snapshot_format *format,
 172                      const char *hex, const char *archive,
 173                      const char *filename)
 174 {
 175         const struct object_id *note = cgit_snapshot_get_sig(hex, format);
 176         enum object_type type;
 177         unsigned long size;
 178         char *buf;
 179
 180         if (!note) {
 181                 cgit_print_error_page(404, "Not found",
 182                                 "No signature for %s", archive);
 183                 return 0;
 184         }
 185
 186         buf = read_object_file(note, &type, &size);
 187         if (!buf) {
 188                 cgit_print_error_page(404, "Not found", "Not found");
 189                 return 0;
 190         }
 191
 192         html("X-Content-Type-Options: nosniff\n");
 193         html("Content-Security-Policy: default-src 'none'\n");
 194         ctx.page.etag = oid_to_hex(note);
 195         ctx.page.mimetype = xstrdup("application/pgp-signature");
 196         ctx.page.filename = xstrdup(filename);
 197         cgit_print_http_headers();
 198
 199         html_raw(buf, size);
 200         free(buf);
 201         return 0;
 202 }
 203
 204 /* Try to guess the requested revision from the requested snapshot name.
 205  * First the format extension is stripped, e.g. "cgit-0.7.2.tar.gz" become
 206  * "cgit-0.7.2". If this is a valid commit object name we've got a winner.
 207  * Otherwise, if the snapshot name has a prefix matching the result from
 208  * repo_basename(), we strip the basename and any following '-' and '_'
 209  * characters ("cgit-0.7.2" -> "0.7.2") and check the resulting name once
 210  * more. If this still isn't a valid commit object name, we check if pre-
 211  * pending a 'v' or a 'V' to the remaining snapshot name ("0.7.2" ->
 212  * "v0.7.2") gives us something valid.
 213  */
 214 static const char *get_ref_from_filename(const struct cgit_repo *repo,
 215                                          const char *filename,
 216                                          const struct cgit_snapshot_format *format)
 217 {
 218         const char *reponame;
 219         struct object_id oid;
 220         struct strbuf snapshot = STRBUF_INIT;
 221         int result = 1;
 222
 223         strbuf_addstr(&snapshot, filename);
 224         strbuf_setlen(&snapshot, snapshot.len - strlen(format->suffix));
 225
 226         if (get_oid(snapshot.buf, &oid) == 0)
 227                 goto out;
 228
 229         reponame = cgit_snapshot_prefix(repo);
 230         if (starts_with(snapshot.buf, reponame)) {
 231                 const char *new_start = snapshot.buf;
 232                 new_start += strlen(reponame);
 233                 while (new_start && (*new_start == '-' || *new_start == '_'))
 234                         new_start++;
 235                 strbuf_splice(&snapshot, 0, new_start - snapshot.buf, "", 0);
 236         }
 237
 238         if (get_oid(snapshot.buf, &oid) == 0)
 239                 goto out;
 240
 241         strbuf_insert(&snapshot, 0, "v", 1);
 242         if (get_oid(snapshot.buf, &oid) == 0)
 243                 goto out;
 244
 245         strbuf_splice(&snapshot, 0, 1, "V", 1);
 246         if (get_oid(snapshot.buf, &oid) == 0)
 247                 goto out;
 248
 249         result = 0;
 250         strbuf_release(&snapshot);
 251
 252 out:
 253         return result ? strbuf_detach(&snapshot, NULL) : NULL;
 254 }
 255
 256 void cgit_print_snapshot(const char *head, const char *hex,
 257                          const char *filename, int dwim)
 258 {
 259         const struct cgit_snapshot_format* f;
 260         const char *sig_filename = NULL;
 261         char *adj_filename = NULL;
 262         char *prefix = NULL;
 263
 264         if (!filename) {
 265                 cgit_print_error_page(400, "Bad request",
 266                                 "No snapshot name specified");
 267                 return;
 268         }
 269
 270         if (ends_with(filename, ".asc")) {
 271                 sig_filename = filename;
 272
 273                 /* Strip ".asc" from filename for common format processing */
 274                 adj_filename = xstrdup(filename);
 275                 adj_filename[strlen(adj_filename) - 4] = '\0';
 276                 filename = adj_filename;
 277         }
 278
 279         f = get_format(filename);
 280         if (!f || (!sig_filename && !(ctx.repo->snapshots & cgit_snapshot_format_bit(f)))) {
 281                 cgit_print_error_page(400, "Bad request",
 282                                 "Unsupported snapshot format: %s", filename);
 283                 return;
 284         }
 285
 286         if (!hex && dwim) {
 287                 hex = get_ref_from_filename(ctx.repo, filename, f);
 288                 if (hex == NULL) {
 289                         cgit_print_error_page(404, "Not found", "Not found");
 290                         return;
 291                 }
 292                 prefix = xstrdup(filename);
 293                 prefix[strlen(filename) - strlen(f->suffix)] = '\0';
 294         }
 295
 296         if (!hex)
 297                 hex = head;
 298
 299         if (!prefix)
 300                 prefix = xstrdup(cgit_snapshot_prefix(ctx.repo));
 301
 302         if (sig_filename)
 303                 write_sig(f, hex, filename, sig_filename);
 304         else
 305                 make_snapshot(f, hex, prefix, filename);
 306
 307         free(prefix);
 308         free(adj_filename);
 309 }