view tests/test-eol.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.

Test EOL extension

  $ cat >> $HGRCPATH <<EOF
  > [diff]
  > git = True
  > EOF

Set up helpers

  $ cat > switch-eol.py <<EOF
  > from __future__ import absolute_import
  > import os
  > import sys
  > try:
  >     import msvcrt
  >     msvcrt.setmode(sys.stdin.fileno(), os.O_BINARY)
  >     msvcrt.setmode(sys.stdout.fileno(), os.O_BINARY)
  > except ImportError:
  >     pass
  > (old, new) = sys.argv[1] == 'LF' and ('\n', '\r\n') or ('\r\n', '\n')
  > print("%% switching encoding from %r to %r" % (old, new))
  > for path in sys.argv[2:]:
  >     data = file(path, 'rb').read()
  >     data = data.replace(old, new)
  >     file(path, 'wb').write(data)
  > EOF

  $ seteol () {
  >     if [ $1 = "LF" ]; then
  >         EOL='\n'
  >     else
  >         EOL='\r\n'
  >     fi
  > }

  $ makerepo () {
  >     seteol $1
  >     echo "% setup $1 repository"
  >     hg init repo
  >     cd repo
  >     cat > .hgeol <<EOF
  > [repository]
  > native = $1
  > [patterns]
  > mixed.txt = BIN
  > **.txt = native
  > EOF
  >     printf "first${EOL}second${EOL}third${EOL}" > a.txt
  >     hg commit --addremove -m 'checkin'
  >     echo
  >     cd ..
  > }

  $ dotest () {
  >     seteol $1
  >     echo "% hg clone repo repo-$1"
  >     hg clone --noupdate repo repo-$1
  >     cd repo-$1
  >     cat > .hg/hgrc <<EOF
  > [extensions]
  > eol =
  > [eol]
  > native = $1
  > EOF
  >     hg update
  >     echo '% a.txt'
  >     cat a.txt
  >     echo '% hg cat a.txt'
  >     hg cat a.txt
  >     printf "fourth${EOL}" >> a.txt
  >     echo '% a.txt'
  >     cat a.txt
  >     hg diff
  >     $PYTHON ../switch-eol.py $1 a.txt
  >     echo '% hg diff only reports a single changed line:'
  >     hg diff
  >     echo "% reverting back to $1 format"
  >     hg revert a.txt
  >     cat a.txt
  >     printf "first\r\nsecond\n" > mixed.txt
  >     hg add mixed.txt
  >     echo "% hg commit of inconsistent .txt file marked as binary (should work)"
  >     hg commit -m 'binary file'
  >     echo "% hg commit of inconsistent .txt file marked as native (should fail)"
  >     printf "first\nsecond\r\nthird\nfourth\r\n" > a.txt
  >     hg commit -m 'inconsistent file'
  >     echo "% hg commit --config eol.only-consistent=False (should work)"
  >     hg commit --config eol.only-consistent=False -m 'inconsistent file'
  >     echo "% hg commit of binary .txt file marked as native (binary files always okay)"
  >     printf "first${EOL}\0${EOL}third${EOL}" > a.txt
  >     hg commit -m 'binary file'
  >     cd ..
  >     rm -r repo-$1
  > }

  $ makemixedrepo () {
  >     echo
  >     echo "# setup $1 repository"
  >     hg init mixed
  >     cd mixed
  >     printf "foo\r\nbar\r\nbaz\r\n" > win.txt
  >     printf "foo\nbar\nbaz\n" > unix.txt
  >     #printf "foo\r\nbar\nbaz\r\n" > mixed.txt
  >     hg commit --addremove -m 'created mixed files'
  >     echo "# setting repository-native EOLs to $1"
  >     cat > .hgeol <<EOF
  > [repository]
  > native = $1
  > [patterns]
  > **.txt = native
  > EOF
  >     hg commit --addremove -m 'added .hgeol'
  >     cd ..
  > }

  $ testmixed () {
  >     echo
  >     echo "% hg clone mixed mixed-$1"
  >     hg clone mixed mixed-$1
  >     cd mixed-$1
  >     echo '% hg status (eol extension not yet activated)'
  >     hg status
  >     cat > .hg/hgrc <<EOF
  > [extensions]
  > eol =
  > [eol]
  > native = $1
  > EOF
  >     echo '% hg status (eol activated)'
  >     hg status
  >     echo '% hg commit'
  >     hg commit -m 'synchronized EOLs'
  >     echo '% hg status'
  >     hg status
  >     cd ..
  >     rm -r mixed-$1
  > }

Basic tests

  $ makerepo LF
  % setup LF repository
  adding .hgeol
  adding a.txt
  
  $ dotest LF
  % hg clone repo repo-LF
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  % a.txt
  first
  second
  third
  % hg cat a.txt
  first
  second
  third
  % a.txt
  first
  second
  third
  fourth
  diff --git a/a.txt b/a.txt
  --- a/a.txt
  +++ b/a.txt
  @@ -1,3 +1,4 @@
   first
   second
   third
  +fourth
  % switching encoding from '\n' to '\r\n'
  % hg diff only reports a single changed line:
  diff --git a/a.txt b/a.txt
  --- a/a.txt
  +++ b/a.txt
  @@ -1,3 +1,4 @@
   first
   second
   third
  +fourth
  % reverting back to LF format
  first
  second
  third
  % hg commit of inconsistent .txt file marked as binary (should work)
  % hg commit of inconsistent .txt file marked as native (should fail)
  abort: inconsistent newline style in a.txt
  
  % hg commit --config eol.only-consistent=False (should work)
  % hg commit of binary .txt file marked as native (binary files always okay)
  $ dotest CRLF
  % hg clone repo repo-CRLF
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  % a.txt
  first\r (esc)
  second\r (esc)
  third\r (esc)
  % hg cat a.txt
  first
  second
  third
  % a.txt
  first\r (esc)
  second\r (esc)
  third\r (esc)
  fourth\r (esc)
  diff --git a/a.txt b/a.txt
  --- a/a.txt
  +++ b/a.txt
  @@ -1,3 +1,4 @@
   first
   second
   third
  +fourth
  % switching encoding from '\r\n' to '\n'
  % hg diff only reports a single changed line:
  diff --git a/a.txt b/a.txt
  --- a/a.txt
  +++ b/a.txt
  @@ -1,3 +1,4 @@
   first
   second
   third
  +fourth
  % reverting back to CRLF format
  first\r (esc)
  second\r (esc)
  third\r (esc)
  % hg commit of inconsistent .txt file marked as binary (should work)
  % hg commit of inconsistent .txt file marked as native (should fail)
  abort: inconsistent newline style in a.txt
  
  % hg commit --config eol.only-consistent=False (should work)
  % hg commit of binary .txt file marked as native (binary files always okay)
  $ rm -r repo
  $ makerepo CRLF
  % setup CRLF repository
  adding .hgeol
  adding a.txt
  
  $ dotest LF
  % hg clone repo repo-LF
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  % a.txt
  first
  second
  third
  % hg cat a.txt
  first\r (esc)
  second\r (esc)
  third\r (esc)
  % a.txt
  first
  second
  third
  fourth
  diff --git a/a.txt b/a.txt
  --- a/a.txt
  +++ b/a.txt
  @@ -1,3 +1,4 @@
   first\r (esc)
   second\r (esc)
   third\r (esc)
  +fourth\r (esc)
  % switching encoding from '\n' to '\r\n'
  % hg diff only reports a single changed line:
  diff --git a/a.txt b/a.txt
  --- a/a.txt
  +++ b/a.txt
  @@ -1,3 +1,4 @@
   first\r (esc)
   second\r (esc)
   third\r (esc)
  +fourth\r (esc)
  % reverting back to LF format
  first
  second
  third
  % hg commit of inconsistent .txt file marked as binary (should work)
  % hg commit of inconsistent .txt file marked as native (should fail)
  abort: inconsistent newline style in a.txt
  
  % hg commit --config eol.only-consistent=False (should work)
  % hg commit of binary .txt file marked as native (binary files always okay)
  $ dotest CRLF
  % hg clone repo repo-CRLF
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  % a.txt
  first\r (esc)
  second\r (esc)
  third\r (esc)
  % hg cat a.txt
  first\r (esc)
  second\r (esc)
  third\r (esc)
  % a.txt
  first\r (esc)
  second\r (esc)
  third\r (esc)
  fourth\r (esc)
  diff --git a/a.txt b/a.txt
  --- a/a.txt
  +++ b/a.txt
  @@ -1,3 +1,4 @@
   first\r (esc)
   second\r (esc)
   third\r (esc)
  +fourth\r (esc)
  % switching encoding from '\r\n' to '\n'
  % hg diff only reports a single changed line:
  diff --git a/a.txt b/a.txt
  --- a/a.txt
  +++ b/a.txt
  @@ -1,3 +1,4 @@
   first\r (esc)
   second\r (esc)
   third\r (esc)
  +fourth\r (esc)
  % reverting back to CRLF format
  first\r (esc)
  second\r (esc)
  third\r (esc)
  % hg commit of inconsistent .txt file marked as binary (should work)
  % hg commit of inconsistent .txt file marked as native (should fail)
  abort: inconsistent newline style in a.txt
  
  % hg commit --config eol.only-consistent=False (should work)
  % hg commit of binary .txt file marked as native (binary files always okay)
  $ rm -r repo

Mixed tests

  $ makemixedrepo LF
  
  # setup LF repository
  adding unix.txt
  adding win.txt
  # setting repository-native EOLs to LF
  adding .hgeol
  $ testmixed LF
  
  % hg clone mixed mixed-LF
  updating to branch default
  3 files updated, 0 files merged, 0 files removed, 0 files unresolved
  % hg status (eol extension not yet activated)
  % hg status (eol activated)
  M win.txt
  % hg commit
  % hg status
  $ testmixed CRLF
  
  % hg clone mixed mixed-CRLF
  updating to branch default
  3 files updated, 0 files merged, 0 files removed, 0 files unresolved
  % hg status (eol extension not yet activated)
  % hg status (eol activated)
  M win.txt
  % hg commit
  % hg status
  $ rm -r mixed
  $ makemixedrepo CRLF
  
  # setup CRLF repository
  adding unix.txt
  adding win.txt
  # setting repository-native EOLs to CRLF
  adding .hgeol
  $ testmixed LF
  
  % hg clone mixed mixed-LF
  updating to branch default
  3 files updated, 0 files merged, 0 files removed, 0 files unresolved
  % hg status (eol extension not yet activated)
  % hg status (eol activated)
  M unix.txt
  % hg commit
  % hg status
  $ testmixed CRLF
  
  % hg clone mixed mixed-CRLF
  updating to branch default
  3 files updated, 0 files merged, 0 files removed, 0 files unresolved
  % hg status (eol extension not yet activated)
  % hg status (eol activated)
  M unix.txt
  % hg commit
  % hg status
  $ rm -r mixed

  $ echo '[extensions]' >> $HGRCPATH
  $ echo 'eol =' >> $HGRCPATH

#if unix-permissions

Test issue2569 -- eol extension takes write lock on reading:

  $ hg init repo
  $ cd repo
  $ touch .hgeol
  $ hg status
  ? .hgeol
  $ chmod -R -w .hg
  $ sleep 1
  $ touch .hgeol
  $ hg status --traceback
  ? .hgeol
  $ chmod -R u+w .hg
  $ cd ..

#endif

Test cleverencode: and cleverdecode: aliases for win32text extension

  $ cat <<EOF >> $HGRCPATH
  > [encode]
  > **.txt = cleverencode:
  > [decode]
  > **.txt = cleverdecode:
  > EOF

  $ hg init win32compat
  $ cd win32compat
  $ printf "foo\r\nbar\r\nbaz\r\n" > win.txt
  $ printf "foo\nbar\nbaz\n" > unix.txt
  $ hg add
  adding unix.txt
  adding win.txt
  $ hg commit -m checkin

Check that both files have LF line-endings in the repository:

  $ hg cat win.txt
  foo
  bar
  baz
  $ hg cat unix.txt
  foo
  bar
  baz

Test handling of a broken .hgeol file:

  $ touch .hgeol
  $ hg add .hgeol
  $ hg commit -m 'clean version'
  $ echo "bad" > .hgeol
  $ hg status
  warning: ignoring .hgeol file due to parse error at .hgeol:1: bad
  M .hgeol
  $ hg revert .hgeol
  warning: ignoring .hgeol file due to parse error at .hgeol:1: bad
  $ hg status
  ? .hgeol.orig

Test eol.only-consistent can be specified in .hgeol

  $ cd $TESTTMP
  $ hg init only-consistent
  $ cd only-consistent
  $ printf "first\nsecond\r\n" > a.txt
  $ hg add a.txt
  $ cat > .hgeol << EOF
  > [eol]
  > only-consistent = True
  > EOF
  $ hg commit -m 'inconsistent'
  abort: inconsistent newline style in a.txt
  
  [255]
  $ cat > .hgeol << EOF
  > [eol]
  > only-consistent = False
  > EOF
  $ hg commit -m 'consistent'

  $ hg init subrepo
  $ hg -R subrepo pull -qu .
  $ echo "subrepo = subrepo" > .hgsub
  $ hg ci -Am "add subrepo"
  adding .hgeol
  adding .hgsub
  $ hg archive -S ../archive
  $ find ../archive/* | sort
  ../archive/a.txt
  ../archive/subrepo
  ../archive/subrepo/a.txt
  $ cat ../archive/a.txt ../archive/subrepo/a.txt
  first\r (esc)
  second\r (esc)
  first\r (esc)
  second\r (esc)

Test trailing newline

  $ cat >> $HGRCPATH <<EOF
  > [extensions]
  > eol=
  > EOF

setup repository

  $ cd $TESTTMP
  $ hg init trailing
  $ cd trailing
  $ cat > .hgeol <<EOF
  > [patterns]
  > **.txt = native
  > [eol]
  > fix-trailing-newline = False
  > EOF

add text without trailing newline

  $ printf "first\nsecond" > a.txt
  $ hg commit --addremove -m 'checking in'
  adding .hgeol
  adding a.txt
  $ rm a.txt
  $ hg update -C -q
  $ cat a.txt
  first
  second (no-eol)

  $ cat > .hgeol <<EOF
  > [patterns]
  > **.txt = native
  > [eol]
  > fix-trailing-newline = True
  > EOF
  $ printf "third\nfourth" > a.txt
  $ hg commit -m 'checking in with newline fix'
  $ rm a.txt
  $ hg update -C -q
  $ cat a.txt
  third
  fourth

append a line without trailing newline

  $ printf "fifth" >> a.txt
  $ hg commit -m 'adding another line line'
  $ rm a.txt
  $ hg update -C -q
  $ cat a.txt
  third
  fourth
  fifth

amend of changesets with renamed/deleted files expose new code paths

  $ hg mv a.txt b.txt
  $ hg ci --amend -q
  $ hg diff -c.
  diff --git a/a.txt b/b.txt
  rename from a.txt
  rename to b.txt
  --- a/a.txt
  +++ b/b.txt
  @@ -1,2 +1,3 @@
   third
   fourth
  +fifth

  $ cd ..