submodule: allow only certain protocols for submodule fetches

Some protocols (like git-remote-ext) can execute arbitrary
code found in the URL. The URLs that submodules use may come
from arbitrary sources (e.g., .gitmodules files in a remote
repository). Let's restrict submodules to fetching from a
known-good subset of protocols.

Note that we apply this restriction to all submodule
commands, whether the URL comes from .gitmodules or not.
This is more restrictive than we need to be; for example, in
the tests we run:

  git submodule add ext::...

which should be trusted, as the URL comes directly from the
command line provided by the user. But doing it this way is
simpler, and makes it much less likely that we would miss a
case. And since such protocols should be an exception
(especially because nobody who clones from them will be able
to update the submodules!), it's not likely to inconvenience
anyone in practice.

Reported-by: Blake Burkhart <bburky@bburky.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2 files changed
tree: 1b94b1eff66ebbc258722f59b60ca64eac0c6de3
  1. block-sha1/
  2. builtin/
  3. compat/
  4. contrib/
  5. Documentation/
  6. ewah/
  7. git-gui/
  8. gitk-git/
  9. gitweb/
  10. mergetools/
  11. perl/
  12. po/
  13. ppc/
  14. t/
  15. templates/
  16. vcs-svn/
  17. xdiff/
  18. .gitattributes
  19. .gitignore
  20. .mailmap
  21. abspath.c
  22. aclocal.m4
  23. advice.c
  24. advice.h
  25. alias.c
  26. alloc.c
  27. archive-tar.c
  28. archive-zip.c
  29. archive.c
  30. archive.h
  31. argv-array.c
  32. argv-array.h
  33. attr.c
  34. attr.h
  35. base85.c
  36. bisect.c
  37. bisect.h
  38. blob.c
  39. blob.h
  40. branch.c
  41. branch.h
  42. builtin.h
  43. bulk-checkin.c
  44. bulk-checkin.h
  45. bundle.c
  46. bundle.h
  47. cache-tree.c
  48. cache-tree.h
  49. cache.h
  50. check-builtins.sh
  51. check-racy.c
  52. check_bindir
  53. color.c
  54. color.h
  55. column.c
  56. column.h
  57. combine-diff.c
  58. command-list.txt
  59. commit-slab.h
  60. commit.c
  61. commit.h
  62. config.c
  63. config.mak.in
  64. config.mak.uname
  65. configure.ac
  66. connect.c
  67. connect.h
  68. connected.c
  69. connected.h
  70. convert.c
  71. convert.h
  72. copy.c
  73. COPYING
  74. credential-cache--daemon.c
  75. credential-cache.c
  76. credential-store.c
  77. credential.c
  78. credential.h
  79. csum-file.c
  80. csum-file.h
  81. ctype.c
  82. daemon.c
  83. date.c
  84. decorate.c
  85. decorate.h
  86. delta.h
  87. diff-delta.c
  88. diff-lib.c
  89. diff-no-index.c
  90. diff.c
  91. diff.h
  92. diffcore-break.c
  93. diffcore-delta.c
  94. diffcore-order.c
  95. diffcore-pickaxe.c
  96. diffcore-rename.c
  97. diffcore.h
  98. dir.c
  99. dir.h
  100. editor.c
  101. entry.c
  102. environment.c
  103. exec_cmd.c
  104. exec_cmd.h
  105. fast-import.c
  106. fetch-pack.c
  107. fetch-pack.h
  108. fmt-merge-msg.h
  109. fsck.c
  110. fsck.h
  111. generate-cmdlist.sh
  112. gettext.c
  113. gettext.h
  114. git-add--interactive.perl
  115. git-am.sh
  116. git-archimport.perl
  117. git-bisect.sh
  118. git-compat-util.h
  119. git-cvsexportcommit.perl
  120. git-cvsimport.perl
  121. git-cvsserver.perl
  122. git-difftool--helper.sh
  123. git-difftool.perl
  124. git-filter-branch.sh
  125. git-instaweb.sh
  126. git-merge-octopus.sh
  127. git-merge-one-file.sh
  128. git-merge-resolve.sh
  129. git-mergetool--lib.sh
  130. git-mergetool.sh
  131. git-p4.py
  132. git-parse-remote.sh
  133. git-pull.sh
  134. git-quiltimport.sh
  135. git-rebase--am.sh
  136. git-rebase--interactive.sh
  137. git-rebase--merge.sh
  138. git-rebase.sh
  139. git-relink.perl
  140. git-remote-testgit.sh
  141. git-request-pull.sh
  142. git-send-email.perl
  143. git-sh-i18n.sh
  144. git-sh-setup.sh
  145. git-stash.sh
  146. git-submodule.sh
  147. git-svn.perl
  148. GIT-VERSION-GEN
  149. git-web--browse.sh
  150. git.c
  151. git.rc
  152. git.spec.in
  153. gpg-interface.c
  154. gpg-interface.h
  155. graph.c
  156. graph.h
  157. grep.c
  158. grep.h
  159. hashmap.c
  160. hashmap.h
  161. help.c
  162. help.h
  163. hex.c
  164. http-backend.c
  165. http-fetch.c
  166. http-push.c
  167. http-walker.c
  168. http.c
  169. http.h
  170. ident.c
  171. imap-send.c
  172. INSTALL
  173. khash.h
  174. kwset.c
  175. kwset.h
  176. levenshtein.c
  177. levenshtein.h
  178. LGPL-2.1
  179. line-log.c
  180. line-log.h
  181. line-range.c
  182. line-range.h
  183. list-objects.c
  184. list-objects.h
  185. ll-merge.c
  186. ll-merge.h
  187. lockfile.c
  188. lockfile.h
  189. log-tree.c
  190. log-tree.h
  191. mailmap.c
  192. mailmap.h
  193. Makefile
  194. match-trees.c
  195. merge-blobs.c
  196. merge-blobs.h
  197. merge-recursive.c
  198. merge-recursive.h
  199. merge.c
  200. mergesort.c
  201. mergesort.h
  202. name-hash.c
  203. notes-cache.c
  204. notes-cache.h
  205. notes-merge.c
  206. notes-merge.h
  207. notes-utils.c
  208. notes-utils.h
  209. notes.c
  210. notes.h
  211. object.c
  212. object.h
  213. pack-bitmap-write.c
  214. pack-bitmap.c
  215. pack-bitmap.h
  216. pack-check.c
  217. pack-objects.c
  218. pack-objects.h
  219. pack-revindex.c
  220. pack-revindex.h
  221. pack-write.c
  222. pack.h
  223. pager.c
  224. parse-options-cb.c
  225. parse-options.c
  226. parse-options.h
  227. patch-delta.c
  228. patch-ids.c
  229. patch-ids.h
  230. path.c
  231. pathspec.c
  232. pathspec.h
  233. pkt-line.c
  234. pkt-line.h
  235. preload-index.c
  236. pretty.c
  237. prio-queue.c
  238. prio-queue.h
  239. progress.c
  240. progress.h
  241. prompt.c
  242. prompt.h
  243. quote.c
  244. quote.h
  245. reachable.c
  246. reachable.h
  247. read-cache.c
  248. README
  249. reflog-walk.c
  250. reflog-walk.h
  251. refs.c
  252. refs.h
  253. remote-curl.c
  254. remote-testsvn.c
  255. remote.c
  256. remote.h
  257. replace_object.c
  258. rerere.c
  259. rerere.h
  260. resolve-undo.c
  261. resolve-undo.h
  262. revision.c
  263. revision.h
  264. run-command.c
  265. run-command.h
  266. send-pack.c
  267. send-pack.h
  268. sequencer.c
  269. sequencer.h
  270. server-info.c
  271. setup.c
  272. sh-i18n--envsubst.c
  273. sha1-array.c
  274. sha1-array.h
  275. sha1-lookup.c
  276. sha1-lookup.h
  277. sha1_file.c
  278. sha1_name.c
  279. shallow.c
  280. shell.c
  281. shortlog.h
  282. show-index.c
  283. sideband.c
  284. sideband.h
  285. sigchain.c
  286. sigchain.h
  287. split-index.c
  288. split-index.h
  289. strbuf.c
  290. strbuf.h
  291. streaming.c
  292. streaming.h
  293. string-list.c
  294. string-list.h
  295. submodule.c
  296. submodule.h
  297. symlinks.c
  298. tag.c
  299. tag.h
  300. tar.h
  301. test-chmtime.c
  302. test-config.c
  303. test-ctype.c
  304. test-date.c
  305. test-delta.c
  306. test-dump-cache-tree.c
  307. test-dump-split-index.c
  308. test-genrandom.c
  309. test-hashmap.c
  310. test-index-version.c
  311. test-line-buffer.c
  312. test-match-trees.c
  313. test-mergesort.c
  314. test-mktemp.c
  315. test-parse-options.c
  316. test-path-utils.c
  317. test-prio-queue.c
  318. test-read-cache.c
  319. test-regex.c
  320. test-revision-walking.c
  321. test-run-command.c
  322. test-scrap-cache-tree.c
  323. test-sha1-array.c
  324. test-sha1.c
  325. test-sha1.sh
  326. test-sigchain.c
  327. test-string-list.c
  328. test-subprocess.c
  329. test-svn-fe.c
  330. test-urlmatch-normalization.c
  331. test-wildmatch.c
  332. thread-utils.c
  333. thread-utils.h
  334. trace.c
  335. trace.h
  336. trailer.c
  337. trailer.h
  338. transport-helper.c
  339. transport.c
  340. transport.h
  341. tree-diff.c
  342. tree-walk.c
  343. tree-walk.h
  344. tree.c
  345. tree.h
  346. unicode_width.h
  347. unimplemented.sh
  348. unix-socket.c
  349. unix-socket.h
  350. unpack-trees.c
  351. unpack-trees.h
  352. update_unicode.sh
  353. upload-pack.c
  354. url.c
  355. url.h
  356. urlmatch.c
  357. urlmatch.h
  358. usage.c
  359. userdiff.c
  360. userdiff.h
  361. utf8.c
  362. utf8.h
  363. varint.c
  364. varint.h
  365. version.c
  366. version.h
  367. versioncmp.c
  368. walker.c
  369. walker.h
  370. wildmatch.c
  371. wildmatch.h
  372. wrap-for-bin.sh
  373. wrapper.c
  374. write_or_die.c
  375. ws.c
  376. wt-status.c
  377. wt-status.h
  378. xdiff-interface.c
  379. xdiff-interface.h
  380. zlib.c