view hgext/gpg.py @ 29021:92d37fb3f1aa stable

verify: don't init subrepo when missing one is referenced (issue5128) (API)

Initializing a subrepo when one doesn't exist is the right thing to do when the
parent is being updated, but in few other cases.  Unfortunately, there isn't
enough context in the subrepo module to distinguish this case.  This same issue
can be caused with other subrepo aware commands, so there is a general issue
here beyond the scope of this fix.

A simpler attempt I tried was to add an '_updating' boolean to localrepo, and
set/clear it around the call to mergemod.update() in hg.updaterepo().  That
mostly worked, but doesn't handle the case where archive will clone the subrepo
if it is missing.  (I vaguely recall that there may be other commands that will
clone if needed like this, but certainly not all do.  It seems both handy, and a
bit surprising for what should be a read only operation.  It might be nice if
all commands did this consistently, but we probably need Angel's subrepo caching
first, to not make a mess of the working directory.)

I originally handled 'Exception' in order to pick up the Aborts raised in
subrepo.state(), but this turns out to be unnecessary because that is called
once and cached by ctx.sub() when iterating the subrepos.

It was suggested in the bug discussion to skip looking at the subrepo links
unless -S is specified.  I don't really like that idea because missing a subrepo
or (less likely, but worse) a corrupt .hgsubstate is a problem of the parent
repo when checking out a revision.  The -S option seems like a better fit for
functionality that would recurse into each subrepo and do a full verification.

Ultimately, the default value for 'allowcreate' should probably be flipped, but
since the default behavior was to allow creation, this is less risky for now.

# Copyright 2005, 2006 Benoit Boissinot <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

'''commands to sign and verify changesets'''

import os, tempfile, binascii
from mercurial import util, commands, match, cmdutil, error
from mercurial import node as hgnode
from mercurial.i18n import _

cmdtable = {}
command = cmdutil.command(cmdtable)
# Note for extension authors: ONLY specify testedwith = 'internal' for
# extensions which SHIP WITH MERCURIAL. Non-mainline extensions should
# be specifying the version(s) of Mercurial they are tested with, or
# leave the attribute unspecified.
testedwith = 'internal'

class gpg(object):
    def __init__(self, path, key=None):
        self.path = path
        self.key = (key and " --local-user \"%s\"" % key) or ""

    def sign(self, data):
        gpgcmd = "%s --sign --detach-sign%s" % (self.path, self.key)
        return util.filter(data, gpgcmd)

    def verify(self, data, sig):
        """ returns of the good and bad signatures"""
        sigfile = datafile = None
        try:
            # create temporary files
            fd, sigfile = tempfile.mkstemp(prefix="hg-gpg-", suffix=".sig")
            fp = os.fdopen(fd, 'wb')
            fp.write(sig)
            fp.close()
            fd, datafile = tempfile.mkstemp(prefix="hg-gpg-", suffix=".txt")
            fp = os.fdopen(fd, 'wb')
            fp.write(data)
            fp.close()
            gpgcmd = ("%s --logger-fd 1 --status-fd 1 --verify "
                      "\"%s\" \"%s\"" % (self.path, sigfile, datafile))
            ret = util.filter("", gpgcmd)
        finally:
            for f in (sigfile, datafile):
                try:
                    if f:
                        os.unlink(f)
                except OSError:
                    pass
        keys = []
        key, fingerprint = None, None
        for l in ret.splitlines():
            # see DETAILS in the gnupg documentation
            # filter the logger output
            if not l.startswith("[GNUPG:]"):
                continue
            l = l[9:]
            if l.startswith("VALIDSIG"):
                # fingerprint of the primary key
                fingerprint = l.split()[10]
            elif l.startswith("ERRSIG"):
                key = l.split(" ", 3)[:2]
                key.append("")
                fingerprint = None
            elif (l.startswith("GOODSIG") or
                  l.startswith("EXPSIG") or
                  l.startswith("EXPKEYSIG") or
                  l.startswith("BADSIG")):
                if key is not None:
                    keys.append(key + [fingerprint])
                key = l.split(" ", 2)
                fingerprint = None
        if key is not None:
            keys.append(key + [fingerprint])
        return keys

def newgpg(ui, **opts):
    """create a new gpg instance"""
    gpgpath = ui.config("gpg", "cmd", "gpg")
    gpgkey = opts.get('key')
    if not gpgkey:
        gpgkey = ui.config("gpg", "key", None)
    return gpg(gpgpath, gpgkey)

def sigwalk(repo):
    """
    walk over every sigs, yields a couple
    ((node, version, sig), (filename, linenumber))
    """
    def parsefile(fileiter, context):
        ln = 1
        for l in fileiter:
            if not l:
                continue
            yield (l.split(" ", 2), (context, ln))
            ln += 1

    # read the heads
    fl = repo.file(".hgsigs")
    for r in reversed(fl.heads()):
        fn = ".hgsigs|%s" % hgnode.short(r)
        for item in parsefile(fl.read(r).splitlines(), fn):
            yield item
    try:
        # read local signatures
        fn = "localsigs"
        for item in parsefile(repo.vfs(fn), fn):
            yield item
    except IOError:
        pass

def getkeys(ui, repo, mygpg, sigdata, context):
    """get the keys who signed a data"""
    fn, ln = context
    node, version, sig = sigdata
    prefix = "%s:%d" % (fn, ln)
    node = hgnode.bin(node)

    data = node2txt(repo, node, version)
    sig = binascii.a2b_base64(sig)
    keys = mygpg.verify(data, sig)

    validkeys = []
    # warn for expired key and/or sigs
    for key in keys:
        if key[0] == "ERRSIG":
            ui.write(_("%s Unknown key ID \"%s\"\n")
                     % (prefix, shortkey(ui, key[1][:15])))
            continue
        if key[0] == "BADSIG":
            ui.write(_("%s Bad signature from \"%s\"\n") % (prefix, key[2]))
            continue
        if key[0] == "EXPSIG":
            ui.write(_("%s Note: Signature has expired"
                       " (signed by: \"%s\")\n") % (prefix, key[2]))
        elif key[0] == "EXPKEYSIG":
            ui.write(_("%s Note: This key has expired"
                       " (signed by: \"%s\")\n") % (prefix, key[2]))
        validkeys.append((key[1], key[2], key[3]))
    return validkeys

@command("sigs", [], _('hg sigs'))
def sigs(ui, repo):
    """list signed changesets"""
    mygpg = newgpg(ui)
    revs = {}

    for data, context in sigwalk(repo):
        node, version, sig = data
        fn, ln = context
        try:
            n = repo.lookup(node)
        except KeyError:
            ui.warn(_("%s:%d node does not exist\n") % (fn, ln))
            continue
        r = repo.changelog.rev(n)
        keys = getkeys(ui, repo, mygpg, data, context)
        if not keys:
            continue
        revs.setdefault(r, [])
        revs[r].extend(keys)
    for rev in sorted(revs, reverse=True):
        for k in revs[rev]:
            r = "%5d:%s" % (rev, hgnode.hex(repo.changelog.node(rev)))
            ui.write("%-30s %s\n" % (keystr(ui, k), r))

@command("sigcheck", [], _('hg sigcheck REV'))
def sigcheck(ui, repo, rev):
    """verify all the signatures there may be for a particular revision"""
    mygpg = newgpg(ui)
    rev = repo.lookup(rev)
    hexrev = hgnode.hex(rev)
    keys = []

    for data, context in sigwalk(repo):
        node, version, sig = data
        if node == hexrev:
            k = getkeys(ui, repo, mygpg, data, context)
            if k:
                keys.extend(k)

    if not keys:
        ui.write(_("no valid signature for %s\n") % hgnode.short(rev))
        return

    # print summary
    ui.write("%s is signed by:\n" % hgnode.short(rev))
    for key in keys:
        ui.write(" %s\n" % keystr(ui, key))

def keystr(ui, key):
    """associate a string to a key (username, comment)"""
    keyid, user, fingerprint = key
    comment = ui.config("gpg", fingerprint, None)
    if comment:
        return "%s (%s)" % (user, comment)
    else:
        return user

@command("sign",
         [('l', 'local', None, _('make the signature local')),
          ('f', 'force', None, _('sign even if the sigfile is modified')),
          ('', 'no-commit', None, _('do not commit the sigfile after signing')),
          ('k', 'key', '',
           _('the key id to sign with'), _('ID')),
          ('m', 'message', '',
           _('use text as commit message'), _('TEXT')),
          ('e', 'edit', False, _('invoke editor on commit messages')),
         ] + commands.commitopts2,
         _('hg sign [OPTION]... [REV]...'))
def sign(ui, repo, *revs, **opts):
    """add a signature for the current or given revision

    If no revision is given, the parent of the working directory is used,
    or tip if no revision is checked out.

    The ``gpg.cmd`` config setting can be used to specify the command
    to run. A default key can be specified with ``gpg.key``.

    See :hg:`help dates` for a list of formats valid for -d/--date.
    """
    with repo.wlock():
        return _dosign(ui, repo, *revs, **opts)

def _dosign(ui, repo, *revs, **opts):
    mygpg = newgpg(ui, **opts)
    sigver = "0"
    sigmessage = ""

    date = opts.get('date')
    if date:
        opts['date'] = util.parsedate(date)

    if revs:
        nodes = [repo.lookup(n) for n in revs]
    else:
        nodes = [node for node in repo.dirstate.parents()
                 if node != hgnode.nullid]
        if len(nodes) > 1:
            raise error.Abort(_('uncommitted merge - please provide a '
                               'specific revision'))
        if not nodes:
            nodes = [repo.changelog.tip()]

    for n in nodes:
        hexnode = hgnode.hex(n)
        ui.write(_("signing %d:%s\n") % (repo.changelog.rev(n),
                                         hgnode.short(n)))
        # build data
        data = node2txt(repo, n, sigver)
        sig = mygpg.sign(data)
        if not sig:
            raise error.Abort(_("error while signing"))
        sig = binascii.b2a_base64(sig)
        sig = sig.replace("\n", "")
        sigmessage += "%s %s %s\n" % (hexnode, sigver, sig)

    # write it
    if opts['local']:
        repo.vfs.append("localsigs", sigmessage)
        return

    if not opts["force"]:
        msigs = match.exact(repo.root, '', ['.hgsigs'])
        if any(repo.status(match=msigs, unknown=True, ignored=True)):
            raise error.Abort(_("working copy of .hgsigs is changed "),
                             hint=_("please commit .hgsigs manually"))

    sigsfile = repo.wfile(".hgsigs", "ab")
    sigsfile.write(sigmessage)
    sigsfile.close()

    if '.hgsigs' not in repo.dirstate:
        repo[None].add([".hgsigs"])

    if opts["no_commit"]:
        return

    message = opts['message']
    if not message:
        # we don't translate commit messages
        message = "\n".join(["Added signature for changeset %s"
                             % hgnode.short(n)
                             for n in nodes])
    try:
        editor = cmdutil.getcommiteditor(editform='gpg.sign', **opts)
        repo.commit(message, opts['user'], opts['date'], match=msigs,
                    editor=editor)
    except ValueError as inst:
        raise error.Abort(str(inst))

def shortkey(ui, key):
    if len(key) != 16:
        ui.debug("key ID \"%s\" format error\n" % key)
        return key

    return key[-8:]

def node2txt(repo, node, ver):
    """map a manifest into some text"""
    if ver == "0":
        return "%s\n" % hgnode.hex(node)
    else:
        raise error.Abort(_("unknown signature version"))