mercurial/hgweb/webutil.py

sslutil: document and slightly refactor validation logic

This main purpose of this patch is to make it clearer that fingerprint
pinning takes precedence over CA verification. This will make
subsequent refactoring to the validation code easier to read.

# hgweb/webutil.py - utility library for the web interface.
#
# Copyright 21 May 2005 - (c) 2005 Jake Edge <[e-mail]>
# Copyright 2005-2007 Matt Mackall <[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.

from __future__ import absolute_import

import copy
import difflib
import os
import re

from ..i18n import _
from ..node import hex, nullid, short

from .common import (
    ErrorResponse,
    HTTP_NOT_FOUND,
    paritygen,
)

from .. import (
    context,
    error,
    match,
    patch,
    pathutil,
    templatefilters,
    ui as uimod,
    util,
)

def up(p):
    if p[0] != "/":
        p = "/" + p
    if p[-1] == "/":
        p = p[:-1]
    up = os.path.dirname(p)
    if up == "/":
        return "/"
    return up + "/"

def _navseq(step, firststep=None):
    if firststep:
        yield firststep
        if firststep >= 20 and firststep <= 40:
            firststep = 50
            yield firststep
        assert step > 0
        assert firststep > 0
        while step <= firststep:
            step *= 10
    while True:
        yield 1 * step
        yield 3 * step
        step *= 10

class revnav(object):

    def __init__(self, repo):
        """Navigation generation object

        :repo: repo object we generate nav for
        """
        # used for hex generation
        self._revlog = repo.changelog

    def __nonzero__(self):
        """return True if any revision to navigate over"""
        return self._first() is not None

    def _first(self):
        """return the minimum non-filtered changeset or None"""
        try:
            return iter(self._revlog).next()
        except StopIteration:
            return None

    def hex(self, rev):
        return hex(self._revlog.node(rev))

    def gen(self, pos, pagelen, limit):
        """computes label and revision id for navigation link

        :pos: is the revision relative to which we generate navigation.
        :pagelen: the size of each navigation page
        :limit: how far shall we link

        The return is:
            - a single element tuple
            - containing a dictionary with a `before` and `after` key
            - values are generator functions taking arbitrary number of kwargs
            - yield items are dictionaries with `label` and `node` keys
        """
        if not self:
            # empty repo
            return ({'before': (), 'after': ()},)

        targets = []
        for f in _navseq(1, pagelen):
            if f > limit:
                break
            targets.append(pos + f)
            targets.append(pos - f)
        targets.sort()

        first = self._first()
        navbefore = [("(%i)" % first, self.hex(first))]
        navafter = []
        for rev in targets:
            if rev not in self._revlog:
                continue
            if pos < rev < limit:
                navafter.append(("+%d" % abs(rev - pos), self.hex(rev)))
            if 0 < rev < pos:
                navbefore.append(("-%d" % abs(rev - pos), self.hex(rev)))


        navafter.append(("tip", "tip"))

        data = lambda i: {"label": i[0], "node": i[1]}
        return ({'before': lambda **map: (data(i) for i in navbefore),
                 'after':  lambda **map: (data(i) for i in navafter)},)

class filerevnav(revnav):

    def __init__(self, repo, path):
        """Navigation generation object

        :repo: repo object we generate nav for
        :path: path of the file we generate nav for
        """
        # used for iteration
        self._changelog = repo.unfiltered().changelog
        # used for hex generation
        self._revlog = repo.file(path)

    def hex(self, rev):
        return hex(self._changelog.node(self._revlog.linkrev(rev)))

class _siblings(object):
    def __init__(self, siblings=[], hiderev=None):
        self.siblings = [s for s in siblings if s.node() != nullid]
        if len(self.siblings) == 1 and self.siblings[0].rev() == hiderev:
            self.siblings = []

    def __iter__(self):
        for s in self.siblings:
            d = {
                'node': s.hex(),
                'rev': s.rev(),
                'user': s.user(),
                'date': s.date(),
                'description': s.description(),
                'branch': s.branch(),
            }
            if util.safehasattr(s, 'path'):
                d['file'] = s.path()
            yield d

    def __len__(self):
        return len(self.siblings)

def parents(ctx, hide=None):
    if isinstance(ctx, context.basefilectx):
        introrev = ctx.introrev()
        if ctx.changectx().rev() != introrev:
            return _siblings([ctx.repo()[introrev]], hide)
    return _siblings(ctx.parents(), hide)

def children(ctx, hide=None):
    return _siblings(ctx.children(), hide)

def renamelink(fctx):
    r = fctx.renamed()
    if r:
        return [{'file': r[0], 'node': hex(r[1])}]
    return []

def nodetagsdict(repo, node):
    return [{"name": i} for i in repo.nodetags(node)]

def nodebookmarksdict(repo, node):
    return [{"name": i} for i in repo.nodebookmarks(node)]

def nodebranchdict(repo, ctx):
    branches = []
    branch = ctx.branch()
    # If this is an empty repo, ctx.node() == nullid,
    # ctx.branch() == 'default'.
    try:
        branchnode = repo.branchtip(branch)
    except error.RepoLookupError:
        branchnode = None
    if branchnode == ctx.node():
        branches.append({"name": branch})
    return branches

def nodeinbranch(repo, ctx):
    branches = []
    branch = ctx.branch()
    try:
        branchnode = repo.branchtip(branch)
    except error.RepoLookupError:
        branchnode = None
    if branch != 'default' and branchnode != ctx.node():
        branches.append({"name": branch})
    return branches

def nodebranchnodefault(ctx):
    branches = []
    branch = ctx.branch()
    if branch != 'default':
        branches.append({"name": branch})
    return branches

def showtag(repo, tmpl, t1, node=nullid, **args):
    for t in repo.nodetags(node):
        yield tmpl(t1, tag=t, **args)

def showbookmark(repo, tmpl, t1, node=nullid, **args):
    for t in repo.nodebookmarks(node):
        yield tmpl(t1, bookmark=t, **args)

def branchentries(repo, stripecount, limit=0):
    tips = []
    heads = repo.heads()
    parity = paritygen(stripecount)
    sortkey = lambda item: (not item[1], item[0].rev())

    def entries(**map):
        count = 0
        if not tips:
            for tag, hs, tip, closed in repo.branchmap().iterbranches():
                tips.append((repo[tip], closed))
        for ctx, closed in sorted(tips, key=sortkey, reverse=True):
            if limit > 0 and count >= limit:
                return
            count += 1
            if closed:
                status = 'closed'
            elif ctx.node() not in heads:
                status = 'inactive'
            else:
                status = 'open'
            yield {
                'parity': parity.next(),
                'branch': ctx.branch(),
                'status': status,
                'node': ctx.hex(),
                'date': ctx.date()
            }

    return entries

def cleanpath(repo, path):
    path = path.lstrip('/')
    return pathutil.canonpath(repo.root, '', path)

def changeidctx(repo, changeid):
    try:
        ctx = repo[changeid]
    except error.RepoError:
        man = repo.manifest
        ctx = repo[man.linkrev(man.rev(man.lookup(changeid)))]

    return ctx

def changectx(repo, req):
    changeid = "tip"
    if 'node' in req.form:
        changeid = req.form['node'][0]
        ipos = changeid.find(':')
        if ipos != -1:
            changeid = changeid[(ipos + 1):]
    elif 'manifest' in req.form:
        changeid = req.form['manifest'][0]

    return changeidctx(repo, changeid)

def basechangectx(repo, req):
    if 'node' in req.form:
        changeid = req.form['node'][0]
        ipos = changeid.find(':')
        if ipos != -1:
            changeid = changeid[:ipos]
            return changeidctx(repo, changeid)

    return None

def filectx(repo, req):
    if 'file' not in req.form:
        raise ErrorResponse(HTTP_NOT_FOUND, 'file not given')
    path = cleanpath(repo, req.form['file'][0])
    if 'node' in req.form:
        changeid = req.form['node'][0]
    elif 'filenode' in req.form:
        changeid = req.form['filenode'][0]
    else:
        raise ErrorResponse(HTTP_NOT_FOUND, 'node or filenode not given')
    try:
        fctx = repo[changeid][path]
    except error.RepoError:
        fctx = repo.filectx(path, fileid=changeid)

    return fctx

def commonentry(repo, ctx):
    node = ctx.node()
    return {
        'rev': ctx.rev(),
        'node': hex(node),
        'author': ctx.user(),
        'desc': ctx.description(),
        'date': ctx.date(),
        'extra': ctx.extra(),
        'phase': ctx.phasestr(),
        'branch': nodebranchnodefault(ctx),
        'inbranch': nodeinbranch(repo, ctx),
        'branches': nodebranchdict(repo, ctx),
        'tags': nodetagsdict(repo, node),
        'bookmarks': nodebookmarksdict(repo, node),
        'parent': lambda **x: parents(ctx),
        'child': lambda **x: children(ctx),
    }

def changelistentry(web, ctx, tmpl):
    '''Obtain a dictionary to be used for entries in a changelist.

    This function is called when producing items for the "entries" list passed
    to the "shortlog" and "changelog" templates.
    '''
    repo = web.repo
    rev = ctx.rev()
    n = ctx.node()
    showtags = showtag(repo, tmpl, 'changelogtag', n)
    files = listfilediffs(tmpl, ctx.files(), n, web.maxfiles)

    entry = commonentry(repo, ctx)
    entry.update(
        allparents=lambda **x: parents(ctx),
        parent=lambda **x: parents(ctx, rev - 1),
        child=lambda **x: children(ctx, rev + 1),
        changelogtag=showtags,
        files=files,
    )
    return entry

def symrevorshortnode(req, ctx):
    if 'node' in req.form:
        return templatefilters.revescape(req.form['node'][0])
    else:
        return short(ctx.node())

def changesetentry(web, req, tmpl, ctx):
    '''Obtain a dictionary to be used to render the "changeset" template.'''

    showtags = showtag(web.repo, tmpl, 'changesettag', ctx.node())
    showbookmarks = showbookmark(web.repo, tmpl, 'changesetbookmark',
                                 ctx.node())
    showbranch = nodebranchnodefault(ctx)

    files = []
    parity = paritygen(web.stripecount)
    for blockno, f in enumerate(ctx.files()):
        template = f in ctx and 'filenodelink' or 'filenolink'
        files.append(tmpl(template,
                          node=ctx.hex(), file=f, blockno=blockno + 1,
                          parity=parity.next()))

    basectx = basechangectx(web.repo, req)
    if basectx is None:
        basectx = ctx.p1()

    style = web.config('web', 'style', 'paper')
    if 'style' in req.form:
        style = req.form['style'][0]

    parity = paritygen(web.stripecount)
    diff = diffs(web.repo, tmpl, ctx, basectx, None, parity, style)

    parity = paritygen(web.stripecount)
    diffstatsgen = diffstatgen(ctx, basectx)
    diffstats = diffstat(tmpl, ctx, diffstatsgen, parity)

    return dict(
        diff=diff,
        symrev=symrevorshortnode(req, ctx),
        basenode=basectx.hex(),
        changesettag=showtags,
        changesetbookmark=showbookmarks,
        changesetbranch=showbranch,
        files=files,
        diffsummary=lambda **x: diffsummary(diffstatsgen),
        diffstat=diffstats,
        archives=web.archivelist(ctx.hex()),
        **commonentry(web.repo, ctx))

def listfilediffs(tmpl, files, node, max):
    for f in files[:max]:
        yield tmpl('filedifflink', node=hex(node), file=f)
    if len(files) > max:
        yield tmpl('fileellipses')

def diffs(repo, tmpl, ctx, basectx, files, parity, style):

    def countgen():
        start = 1
        while True:
            yield start
            start += 1

    blockcount = countgen()
    def prettyprintlines(diff, blockno):
        for lineno, l in enumerate(diff.splitlines(True)):
            difflineno = "%d.%d" % (blockno, lineno + 1)
            if l.startswith('+'):
                ltype = "difflineplus"
            elif l.startswith('-'):
                ltype = "difflineminus"
            elif l.startswith('@'):
                ltype = "difflineat"
            else:
                ltype = "diffline"
            yield tmpl(ltype,
                       line=l,
                       lineno=lineno + 1,
                       lineid="l%s" % difflineno,
                       linenumber="% 8s" % difflineno)

    if files:
        m = match.exact(repo.root, repo.getcwd(), files)
    else:
        m = match.always(repo.root, repo.getcwd())

    diffopts = patch.diffopts(repo.ui, untrusted=True)
    if basectx is None:
        parents = ctx.parents()
        if parents:
            node1 = parents[0].node()
        else:
            node1 = nullid
    else:
        node1 = basectx.node()
    node2 = ctx.node()

    block = []
    for chunk in patch.diff(repo, node1, node2, m, opts=diffopts):
        if chunk.startswith('diff') and block:
            blockno = blockcount.next()
            yield tmpl('diffblock', parity=parity.next(), blockno=blockno,
                       lines=prettyprintlines(''.join(block), blockno))
            block = []
        if chunk.startswith('diff') and style != 'raw':
            chunk = ''.join(chunk.splitlines(True)[1:])
        block.append(chunk)
    blockno = blockcount.next()
    yield tmpl('diffblock', parity=parity.next(), blockno=blockno,
               lines=prettyprintlines(''.join(block), blockno))

def compare(tmpl, context, leftlines, rightlines):
    '''Generator function that provides side-by-side comparison data.'''

    def compline(type, leftlineno, leftline, rightlineno, rightline):
        lineid = leftlineno and ("l%s" % leftlineno) or ''
        lineid += rightlineno and ("r%s" % rightlineno) or ''
        return tmpl('comparisonline',
                    type=type,
                    lineid=lineid,
                    leftlineno=leftlineno,
                    leftlinenumber="% 6s" % (leftlineno or ''),
                    leftline=leftline or '',
                    rightlineno=rightlineno,
                    rightlinenumber="% 6s" % (rightlineno or ''),
                    rightline=rightline or '')

    def getblock(opcodes):
        for type, llo, lhi, rlo, rhi in opcodes:
            len1 = lhi - llo
            len2 = rhi - rlo
            count = min(len1, len2)
            for i in xrange(count):
                yield compline(type=type,
                               leftlineno=llo + i + 1,
                               leftline=leftlines[llo + i],
                               rightlineno=rlo + i + 1,
                               rightline=rightlines[rlo + i])
            if len1 > len2:
                for i in xrange(llo + count, lhi):
                    yield compline(type=type,
                                   leftlineno=i + 1,
                                   leftline=leftlines[i],
                                   rightlineno=None,
                                   rightline=None)
            elif len2 > len1:
                for i in xrange(rlo + count, rhi):
                    yield compline(type=type,
                                   leftlineno=None,
                                   leftline=None,
                                   rightlineno=i + 1,
                                   rightline=rightlines[i])

    s = difflib.SequenceMatcher(None, leftlines, rightlines)
    if context < 0:
        yield tmpl('comparisonblock', lines=getblock(s.get_opcodes()))
    else:
        for oc in s.get_grouped_opcodes(n=context):
            yield tmpl('comparisonblock', lines=getblock(oc))

def diffstatgen(ctx, basectx):
    '''Generator function that provides the diffstat data.'''

    stats = patch.diffstatdata(util.iterlines(ctx.diff(basectx)))
    maxname, maxtotal, addtotal, removetotal, binary = patch.diffstatsum(stats)
    while True:
        yield stats, maxname, maxtotal, addtotal, removetotal, binary

def diffsummary(statgen):
    '''Return a short summary of the diff.'''

    stats, maxname, maxtotal, addtotal, removetotal, binary = statgen.next()
    return _(' %d files changed, %d insertions(+), %d deletions(-)\n') % (
             len(stats), addtotal, removetotal)

def diffstat(tmpl, ctx, statgen, parity):
    '''Return a diffstat template for each file in the diff.'''

    stats, maxname, maxtotal, addtotal, removetotal, binary = statgen.next()
    files = ctx.files()

    def pct(i):
        if maxtotal == 0:
            return 0
        return (float(i) / maxtotal) * 100

    fileno = 0
    for filename, adds, removes, isbinary in stats:
        template = filename in files and 'diffstatlink' or 'diffstatnolink'
        total = adds + removes
        fileno += 1
        yield tmpl(template, node=ctx.hex(), file=filename, fileno=fileno,
                   total=total, addpct=pct(adds), removepct=pct(removes),
                   parity=parity.next())

class sessionvars(object):
    def __init__(self, vars, start='?'):
        self.start = start
        self.vars = vars
    def __getitem__(self, key):
        return self.vars[key]
    def __setitem__(self, key, value):
        self.vars[key] = value
    def __copy__(self):
        return sessionvars(copy.copy(self.vars), self.start)
    def __iter__(self):
        separator = self.start
        for key, value in sorted(self.vars.iteritems()):
            yield {'name': key, 'value': str(value), 'separator': separator}
            separator = '&'

class wsgiui(uimod.ui):
    # default termwidth breaks under mod_wsgi
    def termwidth(self):
        return 80

def getwebsubs(repo):
    websubtable = []
    websubdefs = repo.ui.configitems('websub')
    # we must maintain interhg backwards compatibility
    websubdefs += repo.ui.configitems('interhg')
    for key, pattern in websubdefs:
        # grab the delimiter from the character after the "s"
        unesc = pattern[1]
        delim = re.escape(unesc)

        # identify portions of the pattern, taking care to avoid escaped
        # delimiters. the replace format and flags are optional, but
        # delimiters are required.
        match = re.match(
            r'^s%s(.+)(?:(?<=\\\\)|(?<!\\))%s(.*)%s([ilmsux])*$'
            % (delim, delim, delim), pattern)
        if not match:
            repo.ui.warn(_("websub: invalid pattern for %s: %s\n")
                              % (key, pattern))
            continue

        # we need to unescape the delimiter for regexp and format
        delim_re = re.compile(r'(?<!\\)\\%s' % delim)
        regexp = delim_re.sub(unesc, match.group(1))
        format = delim_re.sub(unesc, match.group(2))

        # the pattern allows for 6 regexp flags, so set them if necessary
        flagin = match.group(3)
        flags = 0
        if flagin:
            for flag in flagin.upper():
                flags |= re.__dict__[flag]

        try:
            regexp = re.compile(regexp, flags)
            websubtable.append((regexp, format))
        except re.error:
            repo.ui.warn(_("websub: invalid regexp for %s: %s\n")
                         % (key, regexp))
    return websubtable