# HG changeset patch
# User Pierre-Yves David <pierre-yves.david@octobus.net>
# Date 1570419411 14400
# Node ID c17a63eb5d4c6d39567ea2aadd7687af9213526f
# Parent  c88075eb28e3281a4470fde929fbf5a13bda5f8a
sidedata: apply basic but tight security around exchange

We don't currently have code to deal with exchange between repository using
sidedata and repository not using sidedata. Until we implement such code (eg:
dropping side data when pushing to a non-sidedata repo) we prevent the two kind
of repo to speak to each other. This is somewhere similar to what 'treemanifest'
does.

Note that sidedata exchange is broken unless one use changegroup v3 anyway. See
next changeset for details.

Differential Revision: https://phab.mercurial-scm.org/D6939

diff -r c88075eb28e3 -r c17a63eb5d4c mercurial/bundle2.py
--- a/mercurial/bundle2.py	Tue Oct 08 02:19:04 2019 -0400
+++ b/mercurial/bundle2.py	Sun Oct 06 23:36:51 2019 -0400
@@ -1711,6 +1711,8 @@
             part.addparam(
                 b'targetphase', b'%d' % phases.secret, mandatory=False
             )
+        if b'exp-sidedata-flag' in repo.requirements:
+            part.addparam(b'exp-sidedata', b'1')
 
     if opts.get(b'streamv2', False):
         addpartbundlestream2(bundler, repo, stream=True)
@@ -1930,7 +1932,14 @@
 
 
 @parthandler(
-    b'changegroup', (b'version', b'nbchanges', b'treemanifest', b'targetphase')
+    b'changegroup',
+    (
+        b'version',
+        b'nbchanges',
+        b'exp-sidedata',
+        b'treemanifest',
+        b'targetphase',
+    ),
 )
 def handlechangegroup(op, inpart):
     """apply a changegroup part on the repo
@@ -1965,6 +1974,14 @@
             op.repo.ui, op.repo.requirements, op.repo.features
         )
         op.repo._writerequirements()
+
+    bundlesidedata = bool(b'exp-sidedata' in inpart.params)
+    reposidedata = bool(b'exp-sidedata-flag' in op.repo.requirements)
+    if reposidedata and not bundlesidedata:
+        msg = b"repository is using sidedata but the bundle source do not"
+        hint = b'this is currently unsupported'
+        raise error.Abort(msg, hint=hint)
+
     extrakwargs = {}
     targetphase = inpart.params.get(b'targetphase')
     if targetphase is not None:
@@ -2551,5 +2568,7 @@
         part.addparam(b'version', cgversion)
         if b'treemanifest' in repo.requirements:
             part.addparam(b'treemanifest', b'1')
+        if b'exp-sidedata-flag' in repo.requirements:
+            part.addparam(b'exp-sidedata', b'1')
 
     return bundler
diff -r c88075eb28e3 -r c17a63eb5d4c mercurial/exchange.py
--- a/mercurial/exchange.py	Tue Oct 08 02:19:04 2019 -0400
+++ b/mercurial/exchange.py	Sun Oct 06 23:36:51 2019 -0400
@@ -1049,6 +1049,8 @@
         cgpart.addparam(b'version', version)
     if b'treemanifest' in pushop.repo.requirements:
         cgpart.addparam(b'treemanifest', b'1')
+    if b'exp-sidedata-flag' in pushop.repo.requirements:
+        cgpart.addparam(b'exp-sidedata', b'1')
 
     def handlereply(op):
         """extract addchangegroup returns from server reply"""
@@ -2511,6 +2513,9 @@
     if b'treemanifest' in repo.requirements:
         part.addparam(b'treemanifest', b'1')
 
+    if b'exp-sidedata-flag' in repo.requirements:
+        part.addparam(b'exp-sidedata', b'1')
+
     if (
         kwargs.get(r'narrow', False)
         and kwargs.get(r'narrow_acl', False)