view tests/test-convert-bzr.t @ 36755:ff4bc0ab6740 stable

wireproto: check permissions when executing "batch" command (BC) (SEC)

For as long as the "batch" command has existed (introduced by
bd88561afb4b and first released as part of Mercurial 1.9), that command
(like most wire commands introduced after 2008) lacked an entry in
the hgweb permissions table. And since we don't verify permissions if
an entry is missing from the permissions table, this meant that
executing a command via "batch" would bypass all permissions
checks.

The security implications are significant: a Mercurial HTTP server
would allow writes via "batch" wire protocol commands as long as
the HTTP request were processed by Mercurial and the process running
the Mercurial HTTP server had write access to the repository. The
Mercurial defaults of servers being read-only and the various web.*
config options to define access control were bypassed.

In addition, "batch" could be used to exfiltrate data from servers
that were configured to not allow read access.

Both forms of permissions bypass could be mitigated to some extent
by using HTTP authentication. This would prevent HTTP requests from
hitting Mercurial's server logic. However, any authenticated request
would still be able to bypass permissions checks via "batch" commands.

The easiest exploit was to send "pushkey" commands via "batch" and
modify the state of bookmarks, phases, and obsolescence markers.
However, I suspect a well-crafted HTTP request could trick the server
into running the "unbundle" wire protocol command, effectively
performing a full `hg push` to create new changesets on the remote.

This commit plugs this gaping security hole by having the "batch"
command perform permissions checking on each sub-command that is
being batched. We do this by threading a permissions checking
callable all the way to the protocol handler. The threading is a
bit hacky from a code perspective. But it preserves API compatibility,
which is the proper thing to do on the stable branch.

One of the subtle things we do is assume that a command with an
undefined permission is a "push" command. This is the safest thing to
do from a security perspective: we don't want to take chances that
a command could perform a write even though the server is configured
to not allow writes.

As the test changes demonstrate, it is no longer possible to bypass
permissions via the "batch" wire protocol command.

.. bc::

   The "batch" wire protocol command now enforces permissions of
   each invoked sub-command. Wire protocol commands must define
   their operation type or the "batch" command will assume they
   can write data and will prevent their execution on HTTP servers
   unless the HTTP request method is POST, the server is configured
   to allow pushes, and the (possibly authenticated) HTTP user is
   authorized to perform a push.

#require bzr

  $ . "$TESTDIR/bzr-definitions"

create and rename on the same file in the same step

  $ mkdir test-createandrename
  $ cd test-createandrename
  $ bzr init -q source

test empty repo conversion (issue3233)

  $ hg convert source source-hg
  initializing destination source-hg repository
  scanning source...
  sorting...
  converting...

back to the rename stuff

  $ cd source
  $ echo a > a
  $ echo c > c
  $ echo e > e
  $ bzr add -q a c e
  $ bzr commit -q -m 'Initial add: a, c, e'
  $ bzr mv a b
  a => b
  $ bzr mv c d
  c => d
  $ bzr mv e f
  e => f
  $ echo a2 >> a
  $ mkdir e
  $ bzr add -q a e
  $ bzr commit -q -m 'rename a into b, create a, rename c into d'
  $ cd ..
  $ hg convert source source-hg
  scanning source...
  sorting...
  converting...
  1 Initial add: a, c, e
  0 rename a into b, create a, rename c into d
  $ glog -R source-hg
  o  1@source "rename a into b, create a, rename c into d" files: a b c d e f
  |
  o  0@source "Initial add: a, c, e" files: a c e
  

manifest

  $ hg manifest -R source-hg -r tip
  a
  b
  d
  f

test --rev option

  $ hg convert -r 1 source source-1-hg
  initializing destination source-1-hg repository
  scanning source...
  sorting...
  converting...
  0 Initial add: a, c, e
  $ glog -R source-1-hg
  o  0@source "Initial add: a, c, e" files: a c e
  

test with filemap

  $ cat > filemap <<EOF
  > exclude a
  > EOF
  $ hg convert --filemap filemap source source-filemap-hg
  initializing destination source-filemap-hg repository
  scanning source...
  sorting...
  converting...
  1 Initial add: a, c, e
  0 rename a into b, create a, rename c into d
  $ hg -R source-filemap-hg manifest -r tip
  b
  d
  f

convert from lightweight checkout

  $ bzr checkout --lightweight source source-light
  $ hg convert -s bzr source-light source-light-hg
  initializing destination source-light-hg repository
  warning: lightweight checkouts may cause conversion failures, try with a regular branch instead.
  $TESTTMP/test-createandrename/source-light does not look like a Bazaar repository
  abort: source-light: missing or unsupported repository
  [255]

extract timestamps that look just like hg's {date|isodate}:
yyyy-mm-dd HH:MM zzzz (no seconds!)
compare timestamps

  $ cd source
  $ bzr log | \
  >   sed '/timestamp/!d;s/.\{15\}\([0-9: -]\{16\}\):.. \(.[0-9]\{4\}\)/\1 \2/' \
  >   > ../bzr-timestamps
  $ cd ..
  $ hg -R source-hg log --template "{date|isodate}\n" > hg-timestamps
  $ cmp bzr-timestamps hg-timestamps || diff -u bzr-timestamps hg-timestamps
  $ cd ..

merge

  $ mkdir test-merge
  $ cd test-merge
  $ cat > helper.py <<EOF
  > import sys
  > from bzrlib import workingtree
  > wt = workingtree.WorkingTree.open('.')
  > 
  > message, stamp = sys.argv[1:]
  > wt.commit(message, timestamp=int(stamp))
  > EOF
  $ bzr init -q source
  $ cd source
  $ echo content > a
  $ echo content2 > b
  $ bzr add -q a b
  $ bzr commit -q -m 'Initial add'
  $ cd ..
  $ bzr branch -q source source-improve
  $ cd source
  $ echo more >> a
  $ $PYTHON ../helper.py 'Editing a' 100
  $ cd ../source-improve
  $ echo content3 >> b
  $ $PYTHON ../helper.py 'Editing b' 200
  $ cd ../source
  $ bzr merge -q ../source-improve
  $ bzr commit -q -m 'Merged improve branch'
  $ cd ..
  $ hg convert --datesort source source-hg
  initializing destination source-hg repository
  scanning source...
  sorting...
  converting...
  3 Initial add
  2 Editing a
  1 Editing b
  0 Merged improve branch
  $ glog -R source-hg
  o    3@source "Merged improve branch" files:
  |\
  | o  2@source-improve "Editing b" files: b
  | |
  o |  1@source "Editing a" files: a
  |/
  o  0@source "Initial add" files: a b
  
  $ cd ..

#if symlink execbit

symlinks and executable files

  $ mkdir test-symlinks
  $ cd test-symlinks
  $ bzr init -q source
  $ cd source
  $ touch program
  $ chmod +x program
  $ ln -s program altname
  $ mkdir d
  $ echo a > d/a
  $ ln -s a syma
  $ bzr add -q altname program syma d/a
  $ bzr commit -q -m 'Initial setup'
  $ touch newprog
  $ chmod +x newprog
  $ rm altname
  $ ln -s newprog altname
  $ chmod -x program
  $ bzr add -q newprog
  $ bzr commit -q -m 'Symlink changed, x bits changed'
  $ cd ..
  $ hg convert source source-hg
  initializing destination source-hg repository
  scanning source...
  sorting...
  converting...
  1 Initial setup
  0 Symlink changed, x bits changed
  $ manifest source-hg 0
  % manifest of 0
  644 @ altname
  644   d/a
  755 * program
  644 @ syma
  $ manifest source-hg tip
  % manifest of tip
  644 @ altname
  644   d/a
  755 * newprog
  644   program
  644 @ syma

test the symlinks can be recreated

  $ cd source-hg
  $ hg up
  5 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg cat syma; echo
  a
  $ cd ../..

#endif

Multiple branches

  $ bzr init-repo -q --no-trees repo
  $ bzr init -q repo/trunk
  $ bzr co repo/trunk repo-trunk
  $ cd repo-trunk
  $ echo a > a
  $ bzr add -q a
  $ bzr ci -qm adda
  $ bzr tag trunk-tag
  Created tag trunk-tag.
  $ bzr switch -b branch
  Tree is up to date at revision 1.
  Switched to branch: *repo/branch/ (glob)
  $ sleep 1
  $ echo b > b
  $ bzr add -q b
  $ bzr ci -qm addb
  $ bzr tag branch-tag
  Created tag branch-tag.
  $ bzr switch --force ../repo/trunk
  Updated to revision 1.
  Switched to branch: */repo/trunk/ (glob)
  $ sleep 1
  $ echo a >> a
  $ bzr ci -qm changea
  $ cd ..
  $ hg convert --datesort repo repo-bzr
  initializing destination repo-bzr repository
  scanning source...
  sorting...
  converting...
  2 adda
  1 addb
  0 changea
  updating tags
  $ (cd repo-bzr; glog)
  o  3@default "update tags" files: .hgtags
  |
  o  2@default "changea" files: a
  |
  | o  1@branch "addb" files: b
  |/
  o  0@default "adda" files: a
  

Test tags (converted identifiers are not stable because bzr ones are
not and get incorporated in extra fields).

  $ hg -R repo-bzr tags
  tip                                3:* (glob)
  branch-tag                         1:* (glob)
  trunk-tag                          0:* (glob)

Nested repositories (issue3254)

  $ bzr init-repo -q --no-trees repo/inner
  $ bzr init -q repo/inner/trunk
  $ bzr co repo/inner/trunk inner-trunk
  $ cd inner-trunk
  $ echo b > b
  $ bzr add -q b
  $ bzr ci -qm addb
  $ cd ..
  $ hg convert --datesort repo noinner-bzr
  initializing destination noinner-bzr repository
  scanning source...
  sorting...
  converting...
  2 adda
  1 addb
  0 changea
  updating tags