gecko-dev/netwerk/dns/nsEffectiveTLDService.cpp
2012-05-21 12:12:37 +01:00

248 lines
8.2 KiB
C++

//* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
// This service reads a file of rules describing TLD-like domain names. For a
// complete description of the expected file format and parsing rules, see
// http://wiki.mozilla.org/Gecko:Effective_TLD_Service
#include "mozilla/Util.h"
#include "nsEffectiveTLDService.h"
#include "nsIIDNService.h"
#include "nsNetUtil.h"
#include "prnetdb.h"
#include "mozilla/FunctionTimer.h"
using namespace mozilla;
NS_IMPL_ISUPPORTS1(nsEffectiveTLDService, nsIEffectiveTLDService)
// ----------------------------------------------------------------------
static const ETLDEntry gEntries[] =
#include "etld_data.inc"
;
// ----------------------------------------------------------------------
nsresult
nsEffectiveTLDService::Init()
{
NS_TIME_FUNCTION;
// We'll probably have to rehash at least once, since nsTHashtable doesn't
// use a perfect hash, but at least we'll save a few rehashes along the way.
// Next optimization here is to precompute the hash using something like
// gperf, but one step at a time. :-)
mHash.Init(ArrayLength(gEntries) - 1);
nsresult rv;
mIDNService = do_GetService(NS_IDNSERVICE_CONTRACTID, &rv);
if (NS_FAILED(rv)) return rv;
// Initialize eTLD hash from static array
for (PRUint32 i = 0; i < ArrayLength(gEntries) - 1; i++) {
#ifdef DEBUG
nsDependentCString name(gEntries[i].domain);
nsCAutoString normalizedName(gEntries[i].domain);
NS_ASSERTION(NS_SUCCEEDED(NormalizeHostname(normalizedName)),
"normalization failure!");
NS_ASSERTION(name.Equals(normalizedName), "domain not normalized!");
#endif
nsDomainEntry *entry = mHash.PutEntry(gEntries[i].domain);
NS_ENSURE_TRUE(entry, NS_ERROR_OUT_OF_MEMORY);
entry->SetData(&gEntries[i]);
}
return NS_OK;
}
// External function for dealing with URI's correctly.
// Pulls out the host portion from an nsIURI, and calls through to
// GetPublicSuffixFromHost().
NS_IMETHODIMP
nsEffectiveTLDService::GetPublicSuffix(nsIURI *aURI,
nsACString &aPublicSuffix)
{
NS_ENSURE_ARG_POINTER(aURI);
nsCOMPtr<nsIURI> innerURI = NS_GetInnermostURI(aURI);
NS_ENSURE_ARG_POINTER(innerURI);
nsCAutoString host;
nsresult rv = innerURI->GetAsciiHost(host);
if (NS_FAILED(rv)) return rv;
return GetBaseDomainInternal(host, 0, aPublicSuffix);
}
// External function for dealing with URI's correctly.
// Pulls out the host portion from an nsIURI, and calls through to
// GetBaseDomainFromHost().
NS_IMETHODIMP
nsEffectiveTLDService::GetBaseDomain(nsIURI *aURI,
PRUint32 aAdditionalParts,
nsACString &aBaseDomain)
{
NS_ENSURE_ARG_POINTER(aURI);
nsCOMPtr<nsIURI> innerURI = NS_GetInnermostURI(aURI);
NS_ENSURE_ARG_POINTER(innerURI);
nsCAutoString host;
nsresult rv = innerURI->GetAsciiHost(host);
if (NS_FAILED(rv)) return rv;
return GetBaseDomainInternal(host, aAdditionalParts + 1, aBaseDomain);
}
// External function for dealing with a host string directly: finds the public
// suffix (e.g. co.uk) for the given hostname. See GetBaseDomainInternal().
NS_IMETHODIMP
nsEffectiveTLDService::GetPublicSuffixFromHost(const nsACString &aHostname,
nsACString &aPublicSuffix)
{
// Create a mutable copy of the hostname and normalize it to ACE.
// This will fail if the hostname includes invalid characters.
nsCAutoString normHostname(aHostname);
nsresult rv = NormalizeHostname(normHostname);
if (NS_FAILED(rv)) return rv;
return GetBaseDomainInternal(normHostname, 0, aPublicSuffix);
}
// External function for dealing with a host string directly: finds the base
// domain (e.g. www.co.uk) for the given hostname and number of subdomain parts
// requested. See GetBaseDomainInternal().
NS_IMETHODIMP
nsEffectiveTLDService::GetBaseDomainFromHost(const nsACString &aHostname,
PRUint32 aAdditionalParts,
nsACString &aBaseDomain)
{
// Create a mutable copy of the hostname and normalize it to ACE.
// This will fail if the hostname includes invalid characters.
nsCAutoString normHostname(aHostname);
nsresult rv = NormalizeHostname(normHostname);
if (NS_FAILED(rv)) return rv;
return GetBaseDomainInternal(normHostname, aAdditionalParts + 1, aBaseDomain);
}
// Finds the base domain for a host, with requested number of additional parts.
// This will fail, generating an error, if the host is an IPv4/IPv6 address,
// if more subdomain parts are requested than are available, or if the hostname
// includes characters that are not valid in a URL. Normalization is performed
// on the host string and the result will be in UTF8.
nsresult
nsEffectiveTLDService::GetBaseDomainInternal(nsCString &aHostname,
PRUint32 aAdditionalParts,
nsACString &aBaseDomain)
{
if (aHostname.IsEmpty())
return NS_ERROR_INSUFFICIENT_DOMAIN_LEVELS;
// chomp any trailing dot, and keep track of it for later
bool trailingDot = aHostname.Last() == '.';
if (trailingDot)
aHostname.Truncate(aHostname.Length() - 1);
// check the edge cases of the host being '.' or having a second trailing '.',
// since subsequent checks won't catch it.
if (aHostname.IsEmpty() || aHostname.Last() == '.')
return NS_ERROR_INVALID_ARG;
// Check if we're dealing with an IPv4/IPv6 hostname, and return
PRNetAddr addr;
PRStatus result = PR_StringToNetAddr(aHostname.get(), &addr);
if (result == PR_SUCCESS)
return NS_ERROR_HOST_IS_IP_ADDRESS;
// Walk up the domain tree, most specific to least specific,
// looking for matches at each level. Note that a given level may
// have multiple attributes (e.g. IsWild() and IsNormal()).
const char *prevDomain = nsnull;
const char *currDomain = aHostname.get();
const char *nextDot = strchr(currDomain, '.');
const char *end = currDomain + aHostname.Length();
const char *eTLD = currDomain;
while (1) {
// sanity check the string we're about to look up: it should not begin with
// a '.'; this would mean the hostname began with a '.' or had an
// embedded '..' sequence.
if (*currDomain == '.')
return NS_ERROR_INVALID_ARG;
// perform the hash lookup.
nsDomainEntry *entry = mHash.GetEntry(currDomain);
if (entry) {
if (entry->IsWild() && prevDomain) {
// wildcard rules imply an eTLD one level inferior to the match.
eTLD = prevDomain;
break;
} else if (entry->IsNormal() || !nextDot) {
// specific match, or we've hit the top domain level
eTLD = currDomain;
break;
} else if (entry->IsException()) {
// exception rules imply an eTLD one level superior to the match.
eTLD = nextDot + 1;
break;
}
}
if (!nextDot) {
// we've hit the top domain level; use it by default.
eTLD = currDomain;
break;
}
prevDomain = currDomain;
currDomain = nextDot + 1;
nextDot = strchr(currDomain, '.');
}
// count off the number of requested domains.
const char *begin = aHostname.get();
const char *iter = eTLD;
while (1) {
if (iter == begin)
break;
if (*(--iter) == '.' && aAdditionalParts-- == 0) {
++iter;
++aAdditionalParts;
break;
}
}
if (aAdditionalParts != 0)
return NS_ERROR_INSUFFICIENT_DOMAIN_LEVELS;
aBaseDomain = Substring(iter, end);
// add on the trailing dot, if applicable
if (trailingDot)
aBaseDomain.Append('.');
return NS_OK;
}
// Normalizes the given hostname, component by component. ASCII/ACE
// components are lower-cased, and UTF-8 components are normalized per
// RFC 3454 and converted to ACE.
nsresult
nsEffectiveTLDService::NormalizeHostname(nsCString &aHostname)
{
if (!IsASCII(aHostname)) {
nsresult rv = mIDNService->ConvertUTF8toACE(aHostname, aHostname);
if (NS_FAILED(rv))
return rv;
}
ToLowerCase(aHostname);
return NS_OK;
}