morgan pushed to branch tor-browser-128.2.0esr-14.0-1 at The Tor Project / Applications / Tor Browser

Commits: 600fa3e4 by Pier Angelo Vendrame at 2024-08-27T09:53:22+02:00 fixup! Bug 42472: Spoof timezone in XSLT.

Revert "Bug 42472: Spoof timezone in XSLT."

This reverts commit 7bdf1f4f6cd90346da288435564ca67d1b0e58e5.

- - - - - fb25351a by Fatih at 2024-08-27T09:53:53+02:00 Bug 1891690: Return GMT when RFPTarget::JSDateTimeUTC is enabled. r=timhuang

Differential Revision: https://phabricator.services.mozilla.com/D216411 - - - - - 365873be by Fatih at 2024-08-27T09:54:19+02:00 Bug 1912129: Reduce time precision for EXSLT date time function. r=timhuang

Differential Revision: https://phabricator.services.mozilla.com/D218783 - - - - -

4 changed files:

- browser/components/resistfingerprinting/test/browser/browser.toml - + browser/components/resistfingerprinting/test/browser/browser_exslt_time_precision.js - + browser/components/resistfingerprinting/test/browser/browser_exslt_timezone_load.js - dom/xslt/xslt/txEXSLTFunctions.cpp

Changes:

===================================== browser/components/resistfingerprinting/test/browser/browser.toml ===================================== @@ -196,3 +196,7 @@ lineno = "172"

["browser_timezone.js"] lineno = "176" + +["browser_exslt_timezone_load.js"] + +["browser_exslt_time_precision.js"]

===================================== browser/components/resistfingerprinting/test/browser/browser_exslt_time_precision.js ===================================== @@ -0,0 +1,71 @@ +/** + * Bug 1912129 - A test case for verifying EXSLT date will report second-precise + * time fingerprinting resistance is enabled. + */ + +function getTime(tab) { + const extractTime = function () { + const xslText = ` + <xsl:stylesheet version="1.0" + xmlns:xsl="http://www.w3.org/1999/XSL/Transform" + xmlns:date="http://exslt.org/dates-and-times" + extension-element-prefixes="date"> + <xsl:output method="text" /> + <xsl:template match="/"> + <xsl:value-of select="date:date-time()" /> + </xsl:template> + </xsl:stylesheet>`; + + const parser = new DOMParser(); + const xsltProcessor = new XSLTProcessor(); + const xslStylesheet = parser.parseFromString(xslText, "application/xml"); + xsltProcessor.importStylesheet(xslStylesheet); + const xmlDoc = parser.parseFromString("<test />", "application/xml"); + const styledDoc = xsltProcessor.transformToDocument(xmlDoc); + const time = styledDoc.firstChild.textContent; + + return time; + }; + + const extractTimeExpr = `(${extractTime.toString()})();`; + + return SpecialPowers.spawn( + tab.linkedBrowser, + [extractTimeExpr], + async funccode => content.eval(funccode) + ); +} + +add_task(async function test_new_window() { + await SpecialPowers.pushPrefEnv({ + set: [ + ["privacy.fingerprintingProtection", true], + ["privacy.fingerprintingProtection.overrides", "+ReduceTimerPrecision"], + ], + }); + + // Open a tab for extracting the time from XSLT. + const tab = await BrowserTestUtils.openNewForegroundTab({ + gBrowser, + opening: TEST_PATH + "file_dummy.html", + forceNewProcess: true, + }); + + for (let i = 0; i < 10; i++) { + // eslint-disable-next-line mozilla/no-arbitrary-setTimeout + await new Promise(res => setTimeout(res, 25)); + + // The regex could be a lot shorter (e.g. /.(\d{3})/) but I wrote the whole + // thing to make sure the time is in the expected format and to allow us + // to re-use this regex in the future if we need to. + // Note: Date format is not locale dependent. + const regex = /\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}.(\d{3})[-+]\d{2}:\d{2}/; + const time = await getTime(tab); + const [, milliseconds] = time.match(regex); + + is(milliseconds, "000", "Date's precision was reduced to seconds."); + } + + BrowserTestUtils.removeTab(tab); + await SpecialPowers.popPrefEnv(); +});

===================================== browser/components/resistfingerprinting/test/browser/browser_exslt_timezone_load.js ===================================== @@ -0,0 +1,62 @@ +/** + * Bug 1891690 - A test case for verifying EXSLT date will use Atlantic/Reykjavik + * timezone (GMT and "real" equivalent to UTC) after fingerprinting + * resistance is enabled. + */ + +function getTimeZone(tab) { + const extractTime = function () { + const xslText = ` + <xsl:stylesheet version="1.0" + xmlns:xsl="http://www.w3.org/1999/XSL/Transform" + xmlns:date="http://exslt.org/dates-and-times" + extension-element-prefixes="date"> + <xsl:output method="text" /> + <xsl:template match="/"> + <xsl:value-of select="date:date-time()" /> + </xsl:template> + </xsl:stylesheet>`; + + const parser = new DOMParser(); + const xsltProcessor = new XSLTProcessor(); + const xslStylesheet = parser.parseFromString(xslText, "application/xml"); + xsltProcessor.importStylesheet(xslStylesheet); + const xmlDoc = parser.parseFromString("<test />", "application/xml"); + const styledDoc = xsltProcessor.transformToDocument(xmlDoc); + const time = styledDoc.firstChild.textContent; + + return time; + }; + + const extractTimeExpr = `(${extractTime.toString()})();`; + + return SpecialPowers.spawn( + tab.linkedBrowser, + [extractTimeExpr], + async funccode => content.eval(funccode) + ); +} + +add_task(async function test_new_window() { + await SpecialPowers.pushPrefEnv({ + set: [ + ["privacy.fingerprintingProtection", true], + ["privacy.fingerprintingProtection.overrides", "+JSDateTimeUTC"], + ], + }); + + // Open a tab for extracting the time zone from XSLT. + const tab = await BrowserTestUtils.openNewForegroundTab({ + gBrowser, + opening: TEST_PATH + "file_dummy.html", + forceNewProcess: true, + }); + + SpecialPowers.Cu.getJSTestingFunctions().setTimeZone("America/Toronto"); + const timeZone = await getTimeZone(tab); + + ok(timeZone.endsWith("+00:00"), "Timezone was spoofed."); + + BrowserTestUtils.removeTab(tab); + await SpecialPowers.popPrefEnv(); +});

===================================== dom/xslt/xslt/txEXSLTFunctions.cpp ===================================== @@ -590,14 +590,22 @@ nsresult txEXSLTFunctionCall::evaluate(txIEvalContext* aContext, // http://exslt.org/date/functions/date-time/

PRExplodedTime prtime; - PR_ExplodeTime(PR_Now(), - nsContentUtils::ShouldResistFingerprinting( - "We are not allowed to access the document at this " - "stage (we are given a txEarlyEvalContext context).", - RFPTarget::JSDateTimeUTC) - ? PR_GMTParameters - : PR_LocalTimeParameters, - &prtime); + Document* sourceDoc = getSourceDocument(aContext); + NS_ENSURE_STATE(sourceDoc); + + PRTimeParamFn timezone = + sourceDoc->ShouldResistFingerprinting(RFPTarget::JSDateTimeUTC) + ? PR_GMTParameters + : PR_LocalTimeParameters; + + PRTime time = + sourceDoc->ShouldResistFingerprinting(RFPTarget::ReduceTimerPrecision) + ? (PRTime)nsRFPService::ReduceTimePrecisionAsSecs( + (double)PR_Now() / PR_USEC_PER_SEC, 0, + RTPCallerType::ResistFingerprinting) * + PR_USEC_PER_SEC + : PR_Now(); + PR_ExplodeTime(time, timezone, &prtime);

int32_t offset = (prtime.tm_params.tp_gmt_offset + prtime.tm_params.tp_dst_offset) / @@ -641,7 +649,7 @@ Expr::ResultType txEXSLTFunctionCall::getReturnType() {

bool txEXSLTFunctionCall::isSensitiveTo(ContextSensitivity aContext) { if (mType == txEXSLTType::NODE_SET || mType == txEXSLTType::SPLIT || - mType == txEXSLTType::TOKENIZE) { + mType == txEXSLTType::TOKENIZE || mType == txEXSLTType::DATE_TIME) { return (aContext & PRIVATE_CONTEXT) || argsSensitiveTo(aContext); } return argsSensitiveTo(aContext);

View it on GitLab: https://gitlab.torproject.org/tpo/applications/tor-browser/-/compare/6253669...