diff options
Diffstat (limited to 'security/manager/ssl/nsNSSIOLayer.cpp')
| -rw-r--r-- | security/manager/ssl/nsNSSIOLayer.cpp | 1740 |
1 files changed, 1740 insertions, 0 deletions
diff --git a/security/manager/ssl/nsNSSIOLayer.cpp b/security/manager/ssl/nsNSSIOLayer.cpp new file mode 100644 index 0000000000..1db4568a1d --- /dev/null +++ b/security/manager/ssl/nsNSSIOLayer.cpp @@ -0,0 +1,1740 @@ +/* -*- 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/. */ + +#include "nsNSSIOLayer.h" + +#include <algorithm> +#include <utility> +#include <vector> + +#include "NSSCertDBTrustDomain.h" +#include "NSSErrorsService.h" +#include "NSSSocketControl.h" +#include "PSMRunnable.h" +#include "SSLServerCertVerification.h" +#include "ScopedNSSTypes.h" +#include "SharedSSLState.h" +#include "TLSClientAuthCertSelection.h" +#include "keyhi.h" +#include "mozilla/Base64.h" +#include "mozilla/Casting.h" +#include "mozilla/DebugOnly.h" +#include "mozilla/Logging.h" +#include "mozilla/Preferences.h" +#include "mozilla/RandomNum.h" +#include "mozilla/StaticPrefs_security.h" +#include "mozilla/Telemetry.h" +#include "mozilla/ipc/BackgroundChild.h" +#include "mozilla/ipc/PBackgroundChild.h" +#include "mozilla/net/SSLTokensCache.h" +#include "mozilla/net/SocketProcessChild.h" +#include "mozilla/psm/IPCClientCertsChild.h" +#include "mozilla/psm/PIPCClientCertsChild.h" +#include "mozpkix/pkixnss.h" +#include "mozpkix/pkixtypes.h" +#include "mozpkix/pkixutil.h" +#include "nsArray.h" +#include "nsArrayUtils.h" +#include "nsCRT.h" +#include "nsCharSeparatedTokenizer.h" +#include "nsClientAuthRemember.h" +#include "nsContentUtils.h" +#include "nsIClientAuthDialogs.h" +#include "nsISocketProvider.h" +#include "nsISocketTransport.h" +#include "nsIWebProgressListener.h" +#include "nsNSSCertHelper.h" +#include "nsNSSComponent.h" +#include "nsNSSHelper.h" +#include "nsPrintfCString.h" +#include "nsServiceManagerUtils.h" +#include "prmem.h" +#include "prnetdb.h" +#include "secder.h" +#include "secerr.h" +#include "ssl.h" +#include "sslerr.h" +#include "sslexp.h" +#include "sslproto.h" + +using namespace mozilla::psm; +using namespace mozilla::ipc; + +// #define DEBUG_SSL_VERBOSE //Enable this define to get minimal +// reports when doing SSL read/write + +// #define DUMP_BUFFER //Enable this define along with +// DEBUG_SSL_VERBOSE to dump SSL +// read/write buffer to a log. +// Uses PR_LOG except on Mac where +// we always write out to our own +// file. + +namespace { + +// The NSSSocketInfo tls flags are meant to be opaque to most calling +// applications but provide a mechanism for direct TLS manipulation when +// experimenting with new features in the scope of a single socket. They do not +// create a persistent ABI. +// +// Use of these flags creates a new 'sharedSSLState' so existing states for +// intolerance are not carried to sockets that use these flags (and intolerance +// they discover does not impact other normal sockets not using the flags.) +// +// Their current definitions are: +// +// bits 0-2 (mask 0x07) specify the max tls version +// 0 means no override 1->4 are 1.0, 1.1, 1.2, 1.3, 4->7 unused +// bits 3-5 (mask 0x38) specify the tls fallback limit +// 0 means no override, values 1->4 match prefs +// bit 6 (mask 0x40) was used to specify compat mode. Temporarily reserved. + +enum { + kTLSProviderFlagMaxVersion10 = 0x01, + kTLSProviderFlagMaxVersion11 = 0x02, + kTLSProviderFlagMaxVersion12 = 0x03, + kTLSProviderFlagMaxVersion13 = 0x04, +}; + +static uint32_t getTLSProviderFlagMaxVersion(uint32_t flags) { + return (flags & 0x07); +} + +static uint32_t getTLSProviderFlagFallbackLimit(uint32_t flags) { + return (flags & 0x38) >> 3; +} + +void getSiteKey(const nsACString& hostName, uint16_t port, + /*out*/ nsACString& key) { + key = hostName; + key.AppendLiteral(":"); + key.AppendInt(port); +} + +} // unnamed namespace + +extern LazyLogModule gPIPNSSLog; + +void nsSSLIOLayerHelpers::Cleanup() { + MutexAutoLock lock(mutex); + mTLSIntoleranceInfo.Clear(); + mInsecureFallbackSites.Clear(); +} + +namespace { + +enum Operation { reading, writing, not_reading_or_writing }; + +int32_t checkHandshake(int32_t bytesTransfered, bool wasReading, + PRFileDesc* ssl_layer_fd, NSSSocketControl* socketInfo); + +NSSSocketControl* getSocketInfoIfRunning(PRFileDesc* fd, Operation op) { + if (!fd || !fd->lower || !fd->secret || + fd->identity != nsSSLIOLayerHelpers::nsSSLIOLayerIdentity) { + NS_ERROR("bad file descriptor passed to getSocketInfoIfRunning"); + PR_SetError(PR_BAD_DESCRIPTOR_ERROR, 0); + return nullptr; + } + + NSSSocketControl* socketInfo = (NSSSocketControl*)fd->secret; + + if (socketInfo->IsCanceled()) { + PRErrorCode err = socketInfo->GetErrorCode(); + PR_SetError(err, 0); + if (op == reading || op == writing) { + // We must do TLS intolerance checks for reads and writes, for timeouts + // in particular. + (void)checkHandshake(-1, op == reading, fd, socketInfo); + } + + // If we get here, it is probably because cert verification failed and this + // is the first I/O attempt since that failure. + return nullptr; + } + + return socketInfo; +} + +} // namespace + +static PRStatus nsSSLIOLayerConnect(PRFileDesc* fd, const PRNetAddr* addr, + PRIntervalTime timeout) { + MOZ_LOG(gPIPNSSLog, LogLevel::Debug, + ("[%p] connecting SSL socket\n", (void*)fd)); + if (!getSocketInfoIfRunning(fd, not_reading_or_writing)) return PR_FAILURE; + + PRStatus status = fd->lower->methods->connect(fd->lower, addr, timeout); + if (status != PR_SUCCESS) { + MOZ_LOG(gPIPNSSLog, LogLevel::Error, + ("[%p] Lower layer connect error: %d\n", (void*)fd, PR_GetError())); + return status; + } + + MOZ_LOG(gPIPNSSLog, LogLevel::Debug, ("[%p] Connect\n", (void*)fd)); + return status; +} + +void nsSSLIOLayerHelpers::rememberTolerantAtVersion(const nsACString& hostName, + int16_t port, + uint16_t tolerant) { + nsCString key; + getSiteKey(hostName, port, key); + + MutexAutoLock lock(mutex); + + IntoleranceEntry entry; + if (mTLSIntoleranceInfo.Get(key, &entry)) { + entry.AssertInvariant(); + entry.tolerant = std::max(entry.tolerant, tolerant); + if (entry.intolerant != 0 && entry.intolerant <= entry.tolerant) { + entry.intolerant = entry.tolerant + 1; + entry.intoleranceReason = 0; // lose the reason + } + } else { + entry.tolerant = tolerant; + entry.intolerant = 0; + entry.intoleranceReason = 0; + } + + entry.AssertInvariant(); + + mTLSIntoleranceInfo.InsertOrUpdate(key, entry); +} + +void nsSSLIOLayerHelpers::forgetIntolerance(const nsACString& hostName, + int16_t port) { + nsCString key; + getSiteKey(hostName, port, key); + + MutexAutoLock lock(mutex); + + IntoleranceEntry entry; + if (mTLSIntoleranceInfo.Get(key, &entry)) { + entry.AssertInvariant(); + + entry.intolerant = 0; + entry.intoleranceReason = 0; + + entry.AssertInvariant(); + mTLSIntoleranceInfo.InsertOrUpdate(key, entry); + } +} + +bool nsSSLIOLayerHelpers::fallbackLimitReached(const nsACString& hostName, + uint16_t intolerant) { + if (isInsecureFallbackSite(hostName)) { + return intolerant <= SSL_LIBRARY_VERSION_TLS_1_0; + } + return intolerant <= mVersionFallbackLimit; +} + +// returns true if we should retry the handshake +bool nsSSLIOLayerHelpers::rememberIntolerantAtVersion( + const nsACString& hostName, int16_t port, uint16_t minVersion, + uint16_t intolerant, PRErrorCode intoleranceReason) { + if (intolerant <= minVersion || fallbackLimitReached(hostName, intolerant)) { + // We can't fall back any further. Assume that intolerance isn't the issue. + forgetIntolerance(hostName, port); + return false; + } + + nsCString key; + getSiteKey(hostName, port, key); + + MutexAutoLock lock(mutex); + + IntoleranceEntry entry; + if (mTLSIntoleranceInfo.Get(key, &entry)) { + entry.AssertInvariant(); + if (intolerant <= entry.tolerant) { + // We already know the server is tolerant at an equal or higher version. + return false; + } + if ((entry.intolerant != 0 && intolerant >= entry.intolerant)) { + // We already know that the server is intolerant at a lower version. + return true; + } + } else { + entry.tolerant = 0; + } + + entry.intolerant = intolerant; + entry.intoleranceReason = intoleranceReason; + entry.AssertInvariant(); + mTLSIntoleranceInfo.InsertOrUpdate(key, entry); + + return true; +} + +void nsSSLIOLayerHelpers::adjustForTLSIntolerance( + const nsACString& hostName, int16_t port, + /*in/out*/ SSLVersionRange& range) { + IntoleranceEntry entry; + + { + nsCString key; + getSiteKey(hostName, port, key); + + MutexAutoLock lock(mutex); + if (!mTLSIntoleranceInfo.Get(key, &entry)) { + return; + } + } + + entry.AssertInvariant(); + + if (entry.intolerant != 0) { + // We've tried connecting at a higher range but failed, so try at the + // version we haven't tried yet, unless we have reached the minimum. + if (range.min < entry.intolerant) { + range.max = entry.intolerant - 1; + } + } +} + +PRErrorCode nsSSLIOLayerHelpers::getIntoleranceReason( + const nsACString& hostName, int16_t port) { + IntoleranceEntry entry; + + { + nsCString key; + getSiteKey(hostName, port, key); + + MutexAutoLock lock(mutex); + if (!mTLSIntoleranceInfo.Get(key, &entry)) { + return 0; + } + } + + entry.AssertInvariant(); + return entry.intoleranceReason; +} + +bool nsSSLIOLayerHelpers::nsSSLIOLayerInitialized = false; +PRDescIdentity nsSSLIOLayerHelpers::nsSSLIOLayerIdentity; +PRDescIdentity nsSSLIOLayerHelpers::nsSSLPlaintextLayerIdentity; +PRIOMethods nsSSLIOLayerHelpers::nsSSLIOLayerMethods; +PRIOMethods nsSSLIOLayerHelpers::nsSSLPlaintextLayerMethods; + +static PRStatus nsSSLIOLayerClose(PRFileDesc* fd) { + if (!fd) return PR_FAILURE; + + MOZ_LOG(gPIPNSSLog, LogLevel::Debug, + ("[%p] Shutting down socket\n", (void*)fd)); + + NSSSocketControl* socketInfo = (NSSSocketControl*)fd->secret; + MOZ_ASSERT(socketInfo, "NSSSocketControl was null for an fd"); + + return socketInfo->CloseSocketAndDestroy(); +} + +#if defined(DEBUG_SSL_VERBOSE) && defined(DUMP_BUFFER) +// Dumps a (potentially binary) buffer using SSM_DEBUG. (We could have used +// the version in ssltrace.c, but that's specifically tailored to SSLTRACE.) +# define DUMPBUF_LINESIZE 24 +static void nsDumpBuffer(unsigned char* buf, int len) { + char hexbuf[DUMPBUF_LINESIZE * 3 + 1]; + char chrbuf[DUMPBUF_LINESIZE + 1]; + static const char* hex = "0123456789abcdef"; + int i = 0; + int l = 0; + char ch; + char* c; + char* h; + if (len == 0) return; + hexbuf[DUMPBUF_LINESIZE * 3] = '\0'; + chrbuf[DUMPBUF_LINESIZE] = '\0'; + (void)memset(hexbuf, 0x20, DUMPBUF_LINESIZE * 3); + (void)memset(chrbuf, 0x20, DUMPBUF_LINESIZE); + h = hexbuf; + c = chrbuf; + + while (i < len) { + ch = buf[i]; + + if (l == DUMPBUF_LINESIZE) { + MOZ_LOG(gPIPNSSLog, LogLevel::Debug, ("%s%s\n", hexbuf, chrbuf)); + (void)memset(hexbuf, 0x20, DUMPBUF_LINESIZE * 3); + (void)memset(chrbuf, 0x20, DUMPBUF_LINESIZE); + h = hexbuf; + c = chrbuf; + l = 0; + } + + // Convert a character to hex. + *h++ = hex[(ch >> 4) & 0xf]; + *h++ = hex[ch & 0xf]; + h++; + + // Put the character (if it's printable) into the character buffer. + if ((ch >= 0x20) && (ch <= 0x7e)) { + *c++ = ch; + } else { + *c++ = '.'; + } + i++; + l++; + } + MOZ_LOG(gPIPNSSLog, LogLevel::Debug, ("%s%s\n", hexbuf, chrbuf)); +} + +# define DEBUG_DUMP_BUFFER(buf, len) nsDumpBuffer(buf, len) +#else +# define DEBUG_DUMP_BUFFER(buf, len) +#endif + +namespace { + +uint32_t tlsIntoleranceTelemetryBucket(PRErrorCode err) { + // returns a numeric code for where we track various errors in telemetry + // only errors that cause version fallback are tracked, + // so this is also used to determine which errors can cause version fallback + switch (err) { + case SSL_ERROR_BAD_MAC_ALERT: + return 1; + case SSL_ERROR_BAD_MAC_READ: + return 2; + case SSL_ERROR_HANDSHAKE_FAILURE_ALERT: + return 3; + case SSL_ERROR_HANDSHAKE_UNEXPECTED_ALERT: + return 4; + case SSL_ERROR_ILLEGAL_PARAMETER_ALERT: + return 6; + case SSL_ERROR_NO_CYPHER_OVERLAP: + return 7; + case SSL_ERROR_UNSUPPORTED_VERSION: + return 10; + case SSL_ERROR_PROTOCOL_VERSION_ALERT: + return 11; + case SSL_ERROR_BAD_HANDSHAKE_HASH_VALUE: + return 13; + case SSL_ERROR_DECODE_ERROR_ALERT: + return 14; + case PR_CONNECT_RESET_ERROR: + return 16; + case PR_END_OF_FILE_ERROR: + return 17; + case SSL_ERROR_INTERNAL_ERROR_ALERT: + return 18; + default: + return 0; + } +} + +bool retryDueToTLSIntolerance(PRErrorCode err, NSSSocketControl* socketInfo) { + // This function is supposed to decide which error codes should + // be used to conclude server is TLS intolerant. + // Note this only happens during the initial SSL handshake. + + if (StaticPrefs::security_tls_ech_disable_grease_on_fallback() && + socketInfo->GetEchExtensionStatus() == EchExtensionStatus::kGREASE) { + // Don't record any intolerances if we used ECH GREASE but force a retry. + return true; + } + + SSLVersionRange range = socketInfo->GetTLSVersionRange(); + nsSSLIOLayerHelpers& helpers = socketInfo->SharedState().IOLayerHelpers(); + + if (err == SSL_ERROR_UNSUPPORTED_VERSION && + range.min == SSL_LIBRARY_VERSION_TLS_1_0) { + socketInfo->SetSecurityState(nsIWebProgressListener::STATE_IS_INSECURE | + nsIWebProgressListener::STATE_USES_SSL_3); + } + + // NSS will return SSL_ERROR_RX_MALFORMED_SERVER_HELLO if anti-downgrade + // detected the downgrade. + if (err == SSL_ERROR_INAPPROPRIATE_FALLBACK_ALERT || + err == SSL_ERROR_RX_MALFORMED_SERVER_HELLO) { + // This is a clear signal that we've fallen back too many versions. Treat + // this as a hard failure, but forget any intolerance so that later attempts + // don't use this version (i.e., range.max) and trigger the error again. + + // First, track the original cause of the version fallback. This uses the + // same buckets as the telemetry below, except that bucket 0 will include + // all cases where there wasn't an original reason. + PRErrorCode originalReason = helpers.getIntoleranceReason( + socketInfo->GetHostName(), socketInfo->GetPort()); + Telemetry::Accumulate(Telemetry::SSL_VERSION_FALLBACK_INAPPROPRIATE, + tlsIntoleranceTelemetryBucket(originalReason)); + + helpers.forgetIntolerance(socketInfo->GetHostName(), socketInfo->GetPort()); + + return false; + } + + // When not using a proxy we'll see a connection reset error. + // When using a proxy, we'll see an end of file error. + + // Don't allow STARTTLS connections to fall back on connection resets or + // EOF. + if ((err == PR_CONNECT_RESET_ERROR || err == PR_END_OF_FILE_ERROR) && + socketInfo->GetForSTARTTLS()) { + return false; + } + + uint32_t reason = tlsIntoleranceTelemetryBucket(err); + if (reason == 0) { + return false; + } + + Telemetry::HistogramID pre; + Telemetry::HistogramID post; + switch (range.max) { + case SSL_LIBRARY_VERSION_TLS_1_3: + pre = Telemetry::SSL_TLS13_INTOLERANCE_REASON_PRE; + post = Telemetry::SSL_TLS13_INTOLERANCE_REASON_POST; + break; + case SSL_LIBRARY_VERSION_TLS_1_2: + pre = Telemetry::SSL_TLS12_INTOLERANCE_REASON_PRE; + post = Telemetry::SSL_TLS12_INTOLERANCE_REASON_POST; + break; + case SSL_LIBRARY_VERSION_TLS_1_1: + pre = Telemetry::SSL_TLS11_INTOLERANCE_REASON_PRE; + post = Telemetry::SSL_TLS11_INTOLERANCE_REASON_POST; + break; + case SSL_LIBRARY_VERSION_TLS_1_0: + pre = Telemetry::SSL_TLS10_INTOLERANCE_REASON_PRE; + post = Telemetry::SSL_TLS10_INTOLERANCE_REASON_POST; + break; + default: + MOZ_CRASH("impossible TLS version"); + return false; + } + + // The difference between _PRE and _POST represents how often we avoided + // TLS intolerance fallback due to remembered tolerance. + Telemetry::Accumulate(pre, reason); + + if (!helpers.rememberIntolerantAtVersion(socketInfo->GetHostName(), + socketInfo->GetPort(), range.min, + range.max, err)) { + return false; + } + + Telemetry::Accumulate(post, reason); + + return true; +} + +// Ensure that we haven't added too many errors to fit. +static_assert((SSL_ERROR_END_OF_LIST - SSL_ERROR_BASE) <= 256, + "too many SSL errors"); +static_assert((SEC_ERROR_END_OF_LIST - SEC_ERROR_BASE) <= 256, + "too many SEC errors"); +static_assert((PR_MAX_ERROR - PR_NSPR_ERROR_BASE) <= 128, + "too many NSPR errors"); +static_assert((mozilla::pkix::ERROR_BASE - mozilla::pkix::END_OF_LIST) < 31, + "too many moz::pkix errors"); + +static void reportHandshakeResult(int32_t bytesTransferred, bool wasReading, + PRErrorCode err, + NSSSocketControl* socketInfo) { + uint32_t bucket; + + // A negative bytesTransferred or a 0 read are errors. + if (bytesTransferred > 0) { + bucket = 0; + } else if ((bytesTransferred == 0) && !wasReading) { + // PR_Write() is defined to never return 0, but let's make sure. + // https://developer.mozilla.org/en-US/docs/Mozilla/Projects/NSPR/Reference/PR_Write. + MOZ_ASSERT(false); + bucket = 671; + } else if (IS_SSL_ERROR(err)) { + bucket = err - SSL_ERROR_BASE; + MOZ_ASSERT(bucket > 0); // SSL_ERROR_EXPORT_ONLY_SERVER isn't used. + } else if (IS_SEC_ERROR(err)) { + bucket = (err - SEC_ERROR_BASE) + 256; + } else if ((err >= PR_NSPR_ERROR_BASE) && (err < PR_MAX_ERROR)) { + bucket = (err - PR_NSPR_ERROR_BASE) + 512; + } else if ((err >= mozilla::pkix::ERROR_BASE) && + (err < mozilla::pkix::ERROR_LIMIT)) { + bucket = (err - mozilla::pkix::ERROR_BASE) + 640; + } else { + bucket = 671; + } + + uint32_t flags = socketInfo->GetProviderFlags(); + if (!(flags & nsISocketProvider::IS_RETRY)) { + Telemetry::Accumulate(Telemetry::SSL_HANDSHAKE_RESULT_FIRST_TRY, bucket); + } + + if (flags & nsISocketProvider::BE_CONSERVATIVE) { + Telemetry::Accumulate(Telemetry::SSL_HANDSHAKE_RESULT_CONSERVATIVE, bucket); + } + + switch (socketInfo->GetEchExtensionStatus()) { + case EchExtensionStatus::kGREASE: + Telemetry::Accumulate(Telemetry::SSL_HANDSHAKE_RESULT_ECH_GREASE, bucket); + break; + case EchExtensionStatus::kReal: + Telemetry::Accumulate(Telemetry::SSL_HANDSHAKE_RESULT_ECH, bucket); + break; + default: + break; + } + Telemetry::Accumulate(Telemetry::SSL_HANDSHAKE_RESULT, bucket); + + if (bucket == 0) { + nsCOMPtr<nsITransportSecurityInfo> securityInfo; + if (NS_FAILED(socketInfo->GetSecurityInfo(getter_AddRefs(securityInfo))) || + !securityInfo) { + return; + } + // Web Privacy Telemetry for successful connections. + bool success = true; + + bool usedPrivateDNS = false; + success &= securityInfo->GetUsedPrivateDNS(&usedPrivateDNS) == NS_OK; + + bool madeOCSPRequest = false; + success &= securityInfo->GetMadeOCSPRequests(&madeOCSPRequest) == NS_OK; + + uint16_t protocolVersion = 0; + success &= securityInfo->GetProtocolVersion(&protocolVersion) == NS_OK; + bool usedTLS13 = protocolVersion == 4; + + bool usedECH = false; + success &= securityInfo->GetIsAcceptedEch(&usedECH) == NS_OK; + + // As bucket is 0 we are reporting the results of a sucessful connection + // and so TransportSecurityInfo should be populated. However, this isn't + // happening in all cases, see Bug 1789458. + if (success) { + uint8_t TLSPrivacyResult = 0; + TLSPrivacyResult |= usedTLS13 << 0; + TLSPrivacyResult |= !madeOCSPRequest << 1; + TLSPrivacyResult |= usedPrivateDNS << 2; + TLSPrivacyResult |= usedECH << 3; + + Telemetry::Accumulate(Telemetry::SSL_HANDSHAKE_PRIVACY, TLSPrivacyResult); + } + } +} + +// Check the status of the handshake. This is where PSM checks for TLS +// intolerance and potentially sets up TLS intolerance fallback by noting the +// intolerance, setting the NSPR error to PR_CONNECT_RESET_ERROR, and returning +// -1 as the bytes transferred so that necko retries the connection. +// Otherwise, PSM returns the bytes transferred unchanged. +int32_t checkHandshake(int32_t bytesTransferred, bool wasReading, + PRFileDesc* ssl_layer_fd, NSSSocketControl* socketInfo) { + const PRErrorCode originalError = PR_GetError(); + + // If the connection would block, return early. + if (bytesTransferred < 0 && originalError == PR_WOULD_BLOCK_ERROR) { + PR_SetError(PR_WOULD_BLOCK_ERROR, 0); + return bytesTransferred; + } + + // We only need to do TLS intolerance checking for the first transfer. + bool handleHandshakeResultNow = socketInfo->IsHandshakePending(); + if (!handleHandshakeResultNow) { + // If we've encountered an error since the handshake, ensure the socket + // control is cancelled, so that getSocketInfoIfRunning will correctly + // cause us to fail if another part of Gecko (erroneously) calls an I/O + // function (PR_Send/PR_Recv/etc.) again on this socket. + if (bytesTransferred < 0) { + if (!socketInfo->IsCanceled()) { + socketInfo->SetCanceled(originalError); + } + PR_SetError(originalError, 0); + } + return bytesTransferred; + } + + // TLS intolerant servers only cause the first transfer to fail, so let's + // set the HandshakePending attribute to false so that we don't try this logic + // again in a subsequent transfer. + socketInfo->SetHandshakeNotPending(); + // Report the result once for each handshake. Note that this does not + // get handshakes which are cancelled before any reads or writes + // happen. + reportHandshakeResult(bytesTransferred, wasReading, originalError, + socketInfo); + + // If there was no error, return early. The case where we read 0 bytes is not + // considered an error by NSS, but PSM interprets this as TLS intolerance, so + // we turn it into an error. Writes of 0 bytes are an error, because PR_Write + // is never supposed to return 0. + if (bytesTransferred > 0) { + return bytesTransferred; + } + + // There was some sort of error. Determine what it was and if we want to + // retry the connection due to TLS intolerance. + PRErrorCode errorToUse = originalError; + // Turn zero-length reads into errors and handle zero-length write errors. + if (bytesTransferred == 0) { + if (wasReading) { + errorToUse = PR_END_OF_FILE_ERROR; + } else { + errorToUse = SEC_ERROR_LIBRARY_FAILURE; + } + bytesTransferred = -1; + } + bool wantRetry = retryDueToTLSIntolerance(errorToUse, socketInfo); + // Set the error on the socket control and cancel it. + if (!socketInfo->IsCanceled()) { + socketInfo->SetCanceled(errorToUse); + } + + if (wantRetry) { + MOZ_LOG(gPIPNSSLog, LogLevel::Debug, + ("[%p] checkHandshake: will retry with lower max TLS version", + ssl_layer_fd)); + // Setting the error PR_CONNECT_RESET_ERROR causes necko to retry the + // connection. + PR_SetError(PR_CONNECT_RESET_ERROR, 0); + } else { + PR_SetError(originalError, 0); + } + + return bytesTransferred; +} + +} // namespace + +static int16_t nsSSLIOLayerPoll(PRFileDesc* fd, int16_t in_flags, + int16_t* out_flags) { + if (!out_flags) { + NS_WARNING("nsSSLIOLayerPoll called with null out_flags"); + return 0; + } + + *out_flags = 0; + + NSSSocketControl* socketInfo = + getSocketInfoIfRunning(fd, not_reading_or_writing); + + if (!socketInfo) { + // If we get here, it is probably because certificate validation failed + // and this is the first I/O operation after the failure. + MOZ_LOG( + gPIPNSSLog, LogLevel::Debug, + ("[%p] polling SSL socket right after certificate verification failed " + "or NSS shutdown or SDR logout %d\n", + fd, (int)in_flags)); + + MOZ_ASSERT(in_flags & PR_POLL_EXCEPT, + "Caller did not poll for EXCEPT (canceled)"); + // Since this poll method cannot return errors, we want the caller to call + // PR_Send/PR_Recv right away to get the error, so we tell that we are + // ready for whatever I/O they are asking for. (See getSocketInfoIfRunning). + *out_flags = in_flags | PR_POLL_EXCEPT; // see also bug 480619 + return in_flags; + } + + MOZ_LOG(gPIPNSSLog, LogLevel::Verbose, + (socketInfo->IsWaitingForCertVerification() + ? "[%p] polling SSL socket during certificate verification " + "using lower %d\n" + : "[%p] poll SSL socket using lower %d\n", + fd, (int)in_flags)); + + // We want the handshake to continue during certificate validation, so we + // don't need to do anything special here. libssl automatically blocks when + // it reaches any point that would be unsafe to send/receive something before + // cert validation is complete. + int16_t result = fd->lower->methods->poll(fd->lower, in_flags, out_flags); + MOZ_LOG(gPIPNSSLog, LogLevel::Verbose, + ("[%p] poll SSL socket returned %d\n", (void*)fd, (int)result)); + return result; +} + +nsSSLIOLayerHelpers::nsSSLIOLayerHelpers(uint32_t aTlsFlags) + : mTreatUnsafeNegotiationAsBroken(false), + mTLSIntoleranceInfo(), + mVersionFallbackLimit(SSL_LIBRARY_VERSION_TLS_1_0), + mutex("nsSSLIOLayerHelpers.mutex"), + mTlsFlags(aTlsFlags) {} + +// PSMAvailable and PSMAvailable64 are reachable, but they're unimplemented in +// PSM, so we set an error and return -1. +static int32_t PSMAvailable(PRFileDesc*) { + PR_SetError(PR_NOT_IMPLEMENTED_ERROR, 0); + return -1; +} + +static int64_t PSMAvailable64(PRFileDesc*) { + PR_SetError(PR_NOT_IMPLEMENTED_ERROR, 0); + return -1; +} + +static PRStatus PSMGetsockname(PRFileDesc* fd, PRNetAddr* addr) { + if (!getSocketInfoIfRunning(fd, not_reading_or_writing)) return PR_FAILURE; + + return fd->lower->methods->getsockname(fd->lower, addr); +} + +static PRStatus PSMGetpeername(PRFileDesc* fd, PRNetAddr* addr) { + if (!getSocketInfoIfRunning(fd, not_reading_or_writing)) return PR_FAILURE; + + return fd->lower->methods->getpeername(fd->lower, addr); +} + +static PRStatus PSMGetsocketoption(PRFileDesc* fd, PRSocketOptionData* data) { + if (!getSocketInfoIfRunning(fd, not_reading_or_writing)) return PR_FAILURE; + + return fd->lower->methods->getsocketoption(fd, data); +} + +static PRStatus PSMSetsocketoption(PRFileDesc* fd, + const PRSocketOptionData* data) { + if (!getSocketInfoIfRunning(fd, not_reading_or_writing)) return PR_FAILURE; + + return fd->lower->methods->setsocketoption(fd, data); +} + +static int32_t PSMRecv(PRFileDesc* fd, void* buf, int32_t amount, int flags, + PRIntervalTime timeout) { + NSSSocketControl* socketInfo = getSocketInfoIfRunning(fd, reading); + if (!socketInfo) return -1; + + if (flags != PR_MSG_PEEK && flags != 0) { + PR_SetError(PR_INVALID_ARGUMENT_ERROR, 0); + return -1; + } + + int32_t bytesRead = + fd->lower->methods->recv(fd->lower, buf, amount, flags, timeout); + + MOZ_LOG(gPIPNSSLog, LogLevel::Verbose, + ("[%p] read %d bytes\n", (void*)fd, bytesRead)); + +#ifdef DEBUG_SSL_VERBOSE + DEBUG_DUMP_BUFFER((unsigned char*)buf, bytesRead); +#endif + + return checkHandshake(bytesRead, true, fd, socketInfo); +} + +static int32_t PSMSend(PRFileDesc* fd, const void* buf, int32_t amount, + int flags, PRIntervalTime timeout) { + NSSSocketControl* socketInfo = getSocketInfoIfRunning(fd, writing); + if (!socketInfo) return -1; + + if (flags != 0) { + PR_SetError(PR_INVALID_ARGUMENT_ERROR, 0); + return -1; + } + +#ifdef DEBUG_SSL_VERBOSE + DEBUG_DUMP_BUFFER((unsigned char*)buf, amount); +#endif + + if (socketInfo->IsShortWritePending() && amount > 0) { + // We got "SSL short write" last time, try to flush the pending byte. +#ifdef DEBUG + socketInfo->CheckShortWrittenBuffer(static_cast<const unsigned char*>(buf), + amount); +#endif + + buf = socketInfo->GetShortWritePendingByteRef(); + amount = 1; + + MOZ_LOG(gPIPNSSLog, LogLevel::Verbose, + ("[%p] pushing 1 byte after SSL short write", fd)); + } + + int32_t bytesWritten = + fd->lower->methods->send(fd->lower, buf, amount, flags, timeout); + + // NSS indicates that it can't write all requested data (due to network + // congestion, for example) by returning either one less than the amount + // of data requested or 16383, if the requested amount is greater than + // 16384. We refer to this as a "short write". If we simply returned + // the amount that NSS did write, the layer above us would then call + // PSMSend with a very small amount of data (often 1). This is inefficient + // and can lead to alternating between sending large packets and very small + // packets. To prevent this, we alert the layer calling us that the operation + // would block and that it should be retried later, with the same data. + // When it does, we tell NSS to write the remaining byte it didn't write + // in the previous call. We then return the total number of bytes written, + // which is the number that caused the short write plus the additional byte + // we just wrote out. + + // The 16384 value is based on libssl's maximum buffer size: + // MAX_FRAGMENT_LENGTH - 1 + // + // It's in a private header, though, filed bug 1394822 to expose it. + static const int32_t kShortWrite16k = 16383; + + if ((amount > 1 && bytesWritten == (amount - 1)) || + (amount > kShortWrite16k && bytesWritten == kShortWrite16k)) { + // This is indication of an "SSL short write", block to force retry. + socketInfo->SetShortWritePending( + bytesWritten + 1, // The amount to return after the flush + *(static_cast<const unsigned char*>(buf) + bytesWritten)); + + MOZ_LOG( + gPIPNSSLog, LogLevel::Verbose, + ("[%p] indicated SSL short write for %d bytes (written just %d bytes)", + fd, amount, bytesWritten)); + + bytesWritten = -1; + PR_SetError(PR_WOULD_BLOCK_ERROR, 0); + +#ifdef DEBUG + socketInfo->RememberShortWrittenBuffer( + static_cast<const unsigned char*>(buf)); +#endif + + } else if (socketInfo->IsShortWritePending() && bytesWritten == 1) { + // We have now flushed all pending data in the SSL socket + // after the indicated short write. Tell the upper layer + // it has sent all its data now. + MOZ_LOG(gPIPNSSLog, LogLevel::Verbose, + ("[%p] finished SSL short write", fd)); + + bytesWritten = socketInfo->ResetShortWritePending(); + } + + MOZ_LOG(gPIPNSSLog, LogLevel::Verbose, + ("[%p] wrote %d bytes\n", fd, bytesWritten)); + + return checkHandshake(bytesWritten, false, fd, socketInfo); +} + +static PRStatus PSMBind(PRFileDesc* fd, const PRNetAddr* addr) { + if (!getSocketInfoIfRunning(fd, not_reading_or_writing)) return PR_FAILURE; + + return fd->lower->methods->bind(fd->lower, addr); +} + +static int32_t nsSSLIOLayerRead(PRFileDesc* fd, void* buf, int32_t amount) { + return PSMRecv(fd, buf, amount, 0, PR_INTERVAL_NO_TIMEOUT); +} + +static int32_t nsSSLIOLayerWrite(PRFileDesc* fd, const void* buf, + int32_t amount) { + return PSMSend(fd, buf, amount, 0, PR_INTERVAL_NO_TIMEOUT); +} + +static PRStatus PSMConnectcontinue(PRFileDesc* fd, int16_t out_flags) { + if (!getSocketInfoIfRunning(fd, not_reading_or_writing)) { + return PR_FAILURE; + } + + return fd->lower->methods->connectcontinue(fd, out_flags); +} + +namespace { + +class PrefObserver : public nsIObserver { + public: + NS_DECL_THREADSAFE_ISUPPORTS + NS_DECL_NSIOBSERVER + explicit PrefObserver(nsSSLIOLayerHelpers* aOwner) : mOwner(aOwner) {} + + protected: + virtual ~PrefObserver() = default; + + private: + nsSSLIOLayerHelpers* mOwner; +}; + +} // unnamed namespace + +NS_IMPL_ISUPPORTS(PrefObserver, nsIObserver) + +NS_IMETHODIMP +PrefObserver::Observe(nsISupports* aSubject, const char* aTopic, + const char16_t* someData) { + if (nsCRT::strcmp(aTopic, NS_PREFBRANCH_PREFCHANGE_TOPIC_ID) == 0) { + NS_ConvertUTF16toUTF8 prefName(someData); + + if (prefName.EqualsLiteral( + "security.ssl.treat_unsafe_negotiation_as_broken")) { + bool enabled; + Preferences::GetBool("security.ssl.treat_unsafe_negotiation_as_broken", + &enabled); + mOwner->setTreatUnsafeNegotiationAsBroken(enabled); + } else if (prefName.EqualsLiteral("security.tls.version.fallback-limit")) { + mOwner->loadVersionFallbackLimit(); + } else if (prefName.EqualsLiteral("security.tls.insecure_fallback_hosts")) { + // Changes to the allowlist on the public side will update the pref. + // Don't propagate the changes to the private side. + if (mOwner->isPublic()) { + mOwner->initInsecureFallbackSites(); + } + } + } + return NS_OK; +} + +static int32_t PlaintextRecv(PRFileDesc* fd, void* buf, int32_t amount, + int flags, PRIntervalTime timeout) { + // The shutdownlocker is not needed here because it will already be + // held higher in the stack + NSSSocketControl* socketInfo = nullptr; + + int32_t bytesRead = + fd->lower->methods->recv(fd->lower, buf, amount, flags, timeout); + if (fd->identity == nsSSLIOLayerHelpers::nsSSLPlaintextLayerIdentity) + socketInfo = (NSSSocketControl*)fd->secret; + + if ((bytesRead > 0) && socketInfo) + socketInfo->AddPlaintextBytesRead(bytesRead); + return bytesRead; +} + +nsSSLIOLayerHelpers::~nsSSLIOLayerHelpers() { + // mPrefObserver will only be set if this->Init was called. The GTest tests + // do not call Init. + if (mPrefObserver) { + Preferences::RemoveObserver( + mPrefObserver, "security.ssl.treat_unsafe_negotiation_as_broken"); + Preferences::RemoveObserver(mPrefObserver, + "security.tls.version.fallback-limit"); + Preferences::RemoveObserver(mPrefObserver, + "security.tls.insecure_fallback_hosts"); + } +} + +template <typename R, R return_value, typename... Args> +static R InvalidPRIOMethod(Args...) { + MOZ_ASSERT_UNREACHABLE("I/O method is invalid"); + PR_SetError(PR_NOT_IMPLEMENTED_ERROR, 0); + return return_value; +} + +nsresult nsSSLIOLayerHelpers::Init() { + if (!nsSSLIOLayerInitialized) { + MOZ_ASSERT(NS_IsMainThread()); + nsSSLIOLayerInitialized = true; + nsSSLIOLayerIdentity = PR_GetUniqueIdentity("NSS layer"); + nsSSLIOLayerMethods = *PR_GetDefaultIOMethods(); + + nsSSLIOLayerMethods.fsync = + InvalidPRIOMethod<PRStatus, PR_FAILURE, PRFileDesc*>; + nsSSLIOLayerMethods.seek = + InvalidPRIOMethod<int32_t, -1, PRFileDesc*, int32_t, PRSeekWhence>; + nsSSLIOLayerMethods.seek64 = + InvalidPRIOMethod<int64_t, -1, PRFileDesc*, int64_t, PRSeekWhence>; + nsSSLIOLayerMethods.fileInfo = + InvalidPRIOMethod<PRStatus, PR_FAILURE, PRFileDesc*, PRFileInfo*>; + nsSSLIOLayerMethods.fileInfo64 = + InvalidPRIOMethod<PRStatus, PR_FAILURE, PRFileDesc*, PRFileInfo64*>; + nsSSLIOLayerMethods.writev = + InvalidPRIOMethod<int32_t, -1, PRFileDesc*, const PRIOVec*, int32_t, + PRIntervalTime>; + nsSSLIOLayerMethods.accept = + InvalidPRIOMethod<PRFileDesc*, nullptr, PRFileDesc*, PRNetAddr*, + PRIntervalTime>; + nsSSLIOLayerMethods.listen = + InvalidPRIOMethod<PRStatus, PR_FAILURE, PRFileDesc*, int>; + nsSSLIOLayerMethods.shutdown = + InvalidPRIOMethod<PRStatus, PR_FAILURE, PRFileDesc*, int>; + nsSSLIOLayerMethods.recvfrom = + InvalidPRIOMethod<int32_t, -1, PRFileDesc*, void*, int32_t, int, + PRNetAddr*, PRIntervalTime>; + nsSSLIOLayerMethods.sendto = + InvalidPRIOMethod<int32_t, -1, PRFileDesc*, const void*, int32_t, int, + const PRNetAddr*, PRIntervalTime>; + nsSSLIOLayerMethods.acceptread = + InvalidPRIOMethod<int32_t, -1, PRFileDesc*, PRFileDesc**, PRNetAddr**, + void*, int32_t, PRIntervalTime>; + nsSSLIOLayerMethods.transmitfile = + InvalidPRIOMethod<int32_t, -1, PRFileDesc*, PRFileDesc*, const void*, + int32_t, PRTransmitFileFlags, PRIntervalTime>; + nsSSLIOLayerMethods.sendfile = + InvalidPRIOMethod<int32_t, -1, PRFileDesc*, PRSendFileData*, + PRTransmitFileFlags, PRIntervalTime>; + + nsSSLIOLayerMethods.available = PSMAvailable; + nsSSLIOLayerMethods.available64 = PSMAvailable64; + nsSSLIOLayerMethods.getsockname = PSMGetsockname; + nsSSLIOLayerMethods.getpeername = PSMGetpeername; + nsSSLIOLayerMethods.getsocketoption = PSMGetsocketoption; + nsSSLIOLayerMethods.setsocketoption = PSMSetsocketoption; + nsSSLIOLayerMethods.recv = PSMRecv; + nsSSLIOLayerMethods.send = PSMSend; + nsSSLIOLayerMethods.connectcontinue = PSMConnectcontinue; + nsSSLIOLayerMethods.bind = PSMBind; + + nsSSLIOLayerMethods.connect = nsSSLIOLayerConnect; + nsSSLIOLayerMethods.close = nsSSLIOLayerClose; + nsSSLIOLayerMethods.write = nsSSLIOLayerWrite; + nsSSLIOLayerMethods.read = nsSSLIOLayerRead; + nsSSLIOLayerMethods.poll = nsSSLIOLayerPoll; + + nsSSLPlaintextLayerIdentity = PR_GetUniqueIdentity("Plaintxext PSM layer"); + nsSSLPlaintextLayerMethods = *PR_GetDefaultIOMethods(); + nsSSLPlaintextLayerMethods.recv = PlaintextRecv; + } + + loadVersionFallbackLimit(); + + // non main thread helpers will need to use defaults + if (NS_IsMainThread()) { + bool enabled = false; + Preferences::GetBool("security.ssl.treat_unsafe_negotiation_as_broken", + &enabled); + setTreatUnsafeNegotiationAsBroken(enabled); + + initInsecureFallbackSites(); + + mPrefObserver = new PrefObserver(this); + Preferences::AddStrongObserver( + mPrefObserver, "security.ssl.treat_unsafe_negotiation_as_broken"); + Preferences::AddStrongObserver(mPrefObserver, + "security.tls.version.fallback-limit"); + Preferences::AddStrongObserver(mPrefObserver, + "security.tls.insecure_fallback_hosts"); + } else { + MOZ_ASSERT(mTlsFlags, "Only per socket version can ignore prefs"); + } + + return NS_OK; +} + +void nsSSLIOLayerHelpers::loadVersionFallbackLimit() { + // see nsNSSComponent::SetEnabledTLSVersions for pref handling rules + uint32_t limit = 3; // TLS 1.2 + + if (NS_IsMainThread()) { + limit = Preferences::GetUint("security.tls.version.fallback-limit", + 3); // 3 = TLS 1.2 + } + + // set fallback limit if it is set in the tls flags + uint32_t tlsFlagsFallbackLimit = getTLSProviderFlagFallbackLimit(mTlsFlags); + + if (tlsFlagsFallbackLimit) { + limit = tlsFlagsFallbackLimit; + MOZ_LOG(gPIPNSSLog, LogLevel::Debug, + ("loadVersionFallbackLimit overriden by tlsFlags %d\n", limit)); + } + + SSLVersionRange defaults = {SSL_LIBRARY_VERSION_TLS_1_2, + SSL_LIBRARY_VERSION_TLS_1_2}; + SSLVersionRange filledInRange; + nsNSSComponent::FillTLSVersionRange(filledInRange, limit, limit, defaults); + if (filledInRange.max < SSL_LIBRARY_VERSION_TLS_1_2) { + filledInRange.max = SSL_LIBRARY_VERSION_TLS_1_2; + } + + mVersionFallbackLimit = filledInRange.max; +} + +void nsSSLIOLayerHelpers::clearStoredData() { + MOZ_ASSERT(NS_IsMainThread()); + initInsecureFallbackSites(); + + MutexAutoLock lock(mutex); + mTLSIntoleranceInfo.Clear(); +} + +void nsSSLIOLayerHelpers::setInsecureFallbackSites(const nsCString& str) { + MutexAutoLock lock(mutex); + + mInsecureFallbackSites.Clear(); + + for (const nsACString& host : nsCCharSeparatedTokenizer(str, ',').ToRange()) { + if (!host.IsEmpty()) { + mInsecureFallbackSites.PutEntry(host); + } + } +} + +void nsSSLIOLayerHelpers::initInsecureFallbackSites() { + MOZ_ASSERT(NS_IsMainThread()); + nsAutoCString insecureFallbackHosts; + Preferences::GetCString("security.tls.insecure_fallback_hosts", + insecureFallbackHosts); + setInsecureFallbackSites(insecureFallbackHosts); +} + +bool nsSSLIOLayerHelpers::isPublic() const { + return this == &PublicSSLState()->IOLayerHelpers(); +} + +class FallbackPrefRemover final : public Runnable { + public: + explicit FallbackPrefRemover(const nsACString& aHost) + : mozilla::Runnable("FallbackPrefRemover"), mHost(aHost) {} + NS_IMETHOD Run() override; + + private: + nsCString mHost; +}; + +NS_IMETHODIMP +FallbackPrefRemover::Run() { + MOZ_ASSERT(NS_IsMainThread()); + nsAutoCString oldValue; + Preferences::GetCString("security.tls.insecure_fallback_hosts", oldValue); + nsCString newValue; + for (const nsACString& host : + nsCCharSeparatedTokenizer(oldValue, ',').ToRange()) { + if (host.Equals(mHost)) { + continue; + } + if (!newValue.IsEmpty()) { + newValue.Append(','); + } + newValue.Append(host); + } + Preferences::SetCString("security.tls.insecure_fallback_hosts", newValue); + return NS_OK; +} + +void nsSSLIOLayerHelpers::removeInsecureFallbackSite(const nsACString& hostname, + uint16_t port) { + forgetIntolerance(hostname, port); + { + MutexAutoLock lock(mutex); + if (!mInsecureFallbackSites.Contains(hostname)) { + return; + } + mInsecureFallbackSites.RemoveEntry(hostname); + } + if (!isPublic()) { + return; + } + RefPtr<Runnable> runnable = new FallbackPrefRemover(hostname); + if (NS_IsMainThread()) { + runnable->Run(); + } else { + NS_DispatchToMainThread(runnable); + } +} + +bool nsSSLIOLayerHelpers::isInsecureFallbackSite(const nsACString& hostname) { + MutexAutoLock lock(mutex); + return mInsecureFallbackSites.Contains(hostname); +} + +void nsSSLIOLayerHelpers::setTreatUnsafeNegotiationAsBroken(bool broken) { + MutexAutoLock lock(mutex); + mTreatUnsafeNegotiationAsBroken = broken; +} + +bool nsSSLIOLayerHelpers::treatUnsafeNegotiationAsBroken() { + MutexAutoLock lock(mutex); + return mTreatUnsafeNegotiationAsBroken; +} + +nsresult nsSSLIOLayerNewSocket(int32_t family, const char* host, int32_t port, + nsIProxyInfo* proxy, + const OriginAttributes& originAttributes, + PRFileDesc** fd, + nsITLSSocketControl** tlsSocketControl, + bool forSTARTTLS, uint32_t flags, + uint32_t tlsFlags) { + PRFileDesc* sock = PR_OpenTCPSocket(family); + if (!sock) return NS_ERROR_OUT_OF_MEMORY; + + nsresult rv = + nsSSLIOLayerAddToSocket(family, host, port, proxy, originAttributes, sock, + tlsSocketControl, forSTARTTLS, flags, tlsFlags); + if (NS_FAILED(rv)) { + PR_Close(sock); + return rv; + } + + *fd = sock; + return NS_OK; +} + +static PRFileDesc* nsSSLIOLayerImportFD(PRFileDesc* fd, + NSSSocketControl* infoObject, + const char* host, bool haveHTTPSProxy) { + PRFileDesc* sslSock = SSL_ImportFD(nullptr, fd); + if (!sslSock) { + MOZ_ASSERT_UNREACHABLE("NSS: Error importing socket"); + return nullptr; + } + SSL_SetPKCS11PinArg(sslSock, (nsIInterfaceRequestor*)infoObject); + SSL_HandshakeCallback(sslSock, HandshakeCallback, infoObject); + SSL_SetCanFalseStartCallback(sslSock, CanFalseStartCallback, infoObject); + + // Disable this hook if we connect anonymously. See bug 466080. + uint32_t flags = 0; + infoObject->GetProviderFlags(&flags); + // Provide the client cert to HTTPS proxy no matter if it is anonymous. + if (flags & nsISocketProvider::ANONYMOUS_CONNECT && !haveHTTPSProxy && + !(flags & nsISocketProvider::ANONYMOUS_CONNECT_ALLOW_CLIENT_CERT)) { + SSL_GetClientAuthDataHook(sslSock, nullptr, infoObject); + } else { + SSL_GetClientAuthDataHook(sslSock, SSLGetClientAuthDataHook, infoObject); + } + + if (SECSuccess != + SSL_AuthCertificateHook(sslSock, AuthCertificateHook, infoObject)) { + MOZ_ASSERT_UNREACHABLE("Failed to configure AuthCertificateHook"); + goto loser; + } + + if (SECSuccess != SSL_SetURL(sslSock, host)) { + MOZ_ASSERT_UNREACHABLE("SSL_SetURL failed"); + goto loser; + } + + return sslSock; +loser: + if (sslSock) { + PR_Close(sslSock); + } + return nullptr; +} + +// Please change getSignatureName in nsNSSCallbacks.cpp when changing the list +// here. See NOTE at SSL_SignatureSchemePrefSet call site. +static const SSLSignatureScheme sEnabledSignatureSchemes[] = { + ssl_sig_ecdsa_secp256r1_sha256, + ssl_sig_ecdsa_secp384r1_sha384, + ssl_sig_ecdsa_secp521r1_sha512, + ssl_sig_rsa_pss_sha256, + ssl_sig_rsa_pss_sha384, + ssl_sig_rsa_pss_sha512, + ssl_sig_rsa_pkcs1_sha256, + ssl_sig_rsa_pkcs1_sha384, + ssl_sig_rsa_pkcs1_sha512, +#if !defined(EARLY_BETA_OR_EARLIER) + ssl_sig_ecdsa_sha1, +#endif + ssl_sig_rsa_pkcs1_sha1, +}; + +static nsresult nsSSLIOLayerSetOptions(PRFileDesc* fd, bool forSTARTTLS, + bool haveProxy, const char* host, + int32_t port, + NSSSocketControl* infoObject) { + if (forSTARTTLS || haveProxy) { + if (SECSuccess != SSL_OptionSet(fd, SSL_SECURITY, false)) { + return NS_ERROR_FAILURE; + } + } + + SSLVersionRange range; + if (SSL_VersionRangeGet(fd, &range) != SECSuccess) { + return NS_ERROR_FAILURE; + } + + // Set TLS 1.3 compat mode. + if (SECSuccess != SSL_OptionSet(fd, SSL_ENABLE_TLS13_COMPAT_MODE, PR_TRUE)) { + MOZ_LOG(gPIPNSSLog, LogLevel::Error, + ("[%p] nsSSLIOLayerSetOptions: Setting compat mode failed\n", fd)); + } + + // setting TLS max version + uint32_t versionFlags = + getTLSProviderFlagMaxVersion(infoObject->GetProviderTlsFlags()); + if (versionFlags) { + MOZ_LOG( + gPIPNSSLog, LogLevel::Debug, + ("[%p] nsSSLIOLayerSetOptions: version flags %d\n", fd, versionFlags)); + if (versionFlags == kTLSProviderFlagMaxVersion10) { + range.max = SSL_LIBRARY_VERSION_TLS_1_0; + } else if (versionFlags == kTLSProviderFlagMaxVersion11) { + range.max = SSL_LIBRARY_VERSION_TLS_1_1; + } else if (versionFlags == kTLSProviderFlagMaxVersion12) { + range.max = SSL_LIBRARY_VERSION_TLS_1_2; + } else if (versionFlags == kTLSProviderFlagMaxVersion13) { + range.max = SSL_LIBRARY_VERSION_TLS_1_3; + } else { + MOZ_LOG(gPIPNSSLog, LogLevel::Error, + ("[%p] nsSSLIOLayerSetOptions: unknown version flags %d\n", fd, + versionFlags)); + } + } + + if ((infoObject->GetProviderFlags() & nsISocketProvider::BE_CONSERVATIVE) && + (range.max > SSL_LIBRARY_VERSION_TLS_1_2)) { + MOZ_LOG(gPIPNSSLog, LogLevel::Debug, + ("[%p] nsSSLIOLayerSetOptions: range.max limited to 1.2 due to " + "BE_CONSERVATIVE flag\n", + fd)); + range.max = SSL_LIBRARY_VERSION_TLS_1_2; + } + + uint16_t maxEnabledVersion = range.max; + infoObject->SharedState().IOLayerHelpers().adjustForTLSIntolerance( + infoObject->GetHostName(), infoObject->GetPort(), range); + MOZ_LOG( + gPIPNSSLog, LogLevel::Debug, + ("[%p] nsSSLIOLayerSetOptions: using TLS version range (0x%04x,0x%04x)\n", + fd, static_cast<unsigned int>(range.min), + static_cast<unsigned int>(range.max))); + + // If the user has set their minimum version to something higher than what + // we've now set the maximum to, this will result in an inconsistent version + // range unless we fix it up. This will override their preference, but we only + // do this for sites critical to the operation of the browser (e.g. update + // servers) and telemetry experiments. + if (range.min > range.max) { + range.min = range.max; + } + + if (SSL_VersionRangeSet(fd, &range) != SECSuccess) { + return NS_ERROR_FAILURE; + } + infoObject->SetTLSVersionRange(range); + + // when adjustForTLSIntolerance tweaks the maximum version downward, + // we tell the server using this SCSV so they can detect a downgrade attack + if (range.max < maxEnabledVersion) { + MOZ_LOG(gPIPNSSLog, LogLevel::Debug, + ("[%p] nsSSLIOLayerSetOptions: enabling TLS_FALLBACK_SCSV\n", fd)); + // Some servers will choke if we send the fallback SCSV with TLS 1.2. + if (range.max < SSL_LIBRARY_VERSION_TLS_1_2) { + if (SECSuccess != SSL_OptionSet(fd, SSL_ENABLE_FALLBACK_SCSV, true)) { + return NS_ERROR_FAILURE; + } + } + // tell NSS the max enabled version to make anti-downgrade effective + if (SECSuccess != SSL_SetDowngradeCheckVersion(fd, maxEnabledVersion)) { + return NS_ERROR_FAILURE; + } + } + + // Enable ECH GREASE if suitable. Has no impact if 'real' ECH is being used. + if (range.max >= SSL_LIBRARY_VERSION_TLS_1_3 && + !(infoObject->GetProviderFlags() & (nsISocketProvider::BE_CONSERVATIVE | + nsISocketTransport::DONT_TRY_ECH)) && + StaticPrefs::security_tls_ech_grease_probability()) { + if ((RandomUint64().valueOr(0) % 100) >= + 100 - StaticPrefs::security_tls_ech_grease_probability()) { + MOZ_LOG(gPIPNSSLog, LogLevel::Debug, + ("[%p] nsSSLIOLayerSetOptions: enabling TLS ECH Grease\n", fd)); + if (SECSuccess != SSL_EnableTls13GreaseEch(fd, PR_TRUE)) { + return NS_ERROR_FAILURE; + } + // ECH Padding can be between 1 and 255 + if (SECSuccess != + SSL_SetTls13GreaseEchSize( + fd, std::clamp(StaticPrefs::security_tls_ech_grease_size(), 1U, + 255U))) { + return NS_ERROR_FAILURE; + } + infoObject->UpdateEchExtensionStatus(EchExtensionStatus::kGREASE); + } + } + + // Include a modest set of named groups. + // Please change getKeaGroupName in nsNSSCallbacks.cpp when changing the list + // here. + const SSLNamedGroup namedGroups[] = { + ssl_grp_ec_curve25519, ssl_grp_ec_secp256r1, ssl_grp_ec_secp384r1, + ssl_grp_ec_secp521r1, ssl_grp_ffdhe_2048, ssl_grp_ffdhe_3072}; + if (SECSuccess != SSL_NamedGroupConfig(fd, namedGroups, + mozilla::ArrayLength(namedGroups))) { + return NS_ERROR_FAILURE; + } + // This ensures that we send key shares for X25519 and P-256 in TLS 1.3, so + // that servers are less likely to use HelloRetryRequest. + if (SECSuccess != SSL_SendAdditionalKeyShares(fd, 1)) { + return NS_ERROR_FAILURE; + } + + // NOTE: Should this list ever include ssl_sig_rsa_pss_pss_sha* (or should + // it become possible to enable this scheme via a pref), it is required + // to test that a Delegated Credential containing a small-modulus RSA-PSS SPKI + // is properly rejected. NSS will not advertise PKCS1 or RSAE schemes (which + // the |ssl_sig_rsa_pss_*| defines alias, meaning we will not currently accept + // any RSA DC. + if (SECSuccess != SSL_SignatureSchemePrefSet( + fd, sEnabledSignatureSchemes, + mozilla::ArrayLength(sEnabledSignatureSchemes))) { + return NS_ERROR_FAILURE; + } + + bool enabled = infoObject->SharedState().IsOCSPStaplingEnabled(); + if (SECSuccess != SSL_OptionSet(fd, SSL_ENABLE_OCSP_STAPLING, enabled)) { + return NS_ERROR_FAILURE; + } + + bool sctsEnabled = infoObject->SharedState().IsSignedCertTimestampsEnabled(); + if (SECSuccess != + SSL_OptionSet(fd, SSL_ENABLE_SIGNED_CERT_TIMESTAMPS, sctsEnabled)) { + return NS_ERROR_FAILURE; + } + + if (SECSuccess != SSL_OptionSet(fd, SSL_HANDSHAKE_AS_CLIENT, true)) { + return NS_ERROR_FAILURE; + } + +#if defined(__arm__) && not defined(__ARM_FEATURE_CRYPTO) + unsigned int enabledCiphers = 0; + std::vector<uint16_t> ciphers(SSL_GetNumImplementedCiphers()); + + // Returns only the enabled (reflecting prefs) ciphers, ordered + // by their occurence in + // https://hg.mozilla.org/projects/nss/file/a75ea4cdacd95282c6c245ebb849c25e84ccd908/lib/ssl/ssl3con.c#l87 + if (SSL_CipherSuiteOrderGet(fd, ciphers.data(), &enabledCiphers) != + SECSuccess) { + return NS_ERROR_FAILURE; + } + + // On ARM, prefer (TLS_CHACHA20_POLY1305_SHA256) over AES when hardware + // support for AES isn't available. However, it may be disabled. If enabled, + // it will either be element [0] or [1]*. If [0], we're done. If [1], swap it + // with [0] (TLS_AES_128_GCM_SHA256). + // *(assuming the compile-time order remains unchanged) + if (enabledCiphers > 1) { + if (ciphers[0] != TLS_CHACHA20_POLY1305_SHA256 && + ciphers[1] == TLS_CHACHA20_POLY1305_SHA256) { + std::swap(ciphers[0], ciphers[1]); + + if (SSL_CipherSuiteOrderSet(fd, ciphers.data(), enabledCiphers) != + SECSuccess) { + return NS_ERROR_FAILURE; + } + } + } +#endif + + // Set the Peer ID so that SSL proxy connections work properly and to + // separate anonymous and/or private browsing connections. + nsAutoCString peerId; + infoObject->GetPeerId(peerId); + if (SECSuccess != SSL_SetSockPeerID(fd, peerId.get())) { + return NS_ERROR_FAILURE; + } + + uint32_t flags = infoObject->GetProviderFlags(); + if (flags & nsISocketProvider::NO_PERMANENT_STORAGE) { + if (SECSuccess != SSL_OptionSet(fd, SSL_ENABLE_SESSION_TICKETS, false) || + SECSuccess != SSL_OptionSet(fd, SSL_NO_CACHE, true)) { + return NS_ERROR_FAILURE; + } + } + + return NS_OK; +} + +SECStatus StoreResumptionToken(PRFileDesc* fd, const PRUint8* resumptionToken, + unsigned int len, void* ctx) { + PRIntn val; + if (SSL_OptionGet(fd, SSL_ENABLE_SESSION_TICKETS, &val) != SECSuccess || + val == 0) { + return SECFailure; + } + + NSSSocketControl* infoObject = (NSSSocketControl*)ctx; + if (!infoObject) { + return SECFailure; + } + + nsAutoCString peerId; + infoObject->GetPeerId(peerId); + if (NS_FAILED( + net::SSLTokensCache::Put(peerId, resumptionToken, len, infoObject))) { + return SECFailure; + } + + return SECSuccess; +} + +nsresult nsSSLIOLayerAddToSocket(int32_t family, const char* host, int32_t port, + nsIProxyInfo* proxy, + const OriginAttributes& originAttributes, + PRFileDesc* fd, + nsITLSSocketControl** tlsSocketControl, + bool forSTARTTLS, uint32_t providerFlags, + uint32_t providerTlsFlags) { + PRFileDesc* layer = nullptr; + PRFileDesc* plaintextLayer = nullptr; + nsresult rv; + PRStatus stat; + + SharedSSLState* sharedState = nullptr; + RefPtr<SharedSSLState> allocatedState; + if (providerTlsFlags) { + allocatedState = new SharedSSLState(providerTlsFlags); + sharedState = allocatedState.get(); + } else { + bool isPrivate = providerFlags & nsISocketProvider::NO_PERMANENT_STORAGE || + originAttributes.mPrivateBrowsingId != + OriginAttributes().mPrivateBrowsingId; + sharedState = isPrivate ? PrivateSSLState() : PublicSSLState(); + } + + NSSSocketControl* infoObject = + new NSSSocketControl(nsDependentCString(host), port, *sharedState, + providerFlags, providerTlsFlags); + if (!infoObject) return NS_ERROR_FAILURE; + + NS_ADDREF(infoObject); + infoObject->SetForSTARTTLS(forSTARTTLS); + infoObject->SetOriginAttributes(originAttributes); + if (allocatedState) { + infoObject->SetSharedOwningReference(allocatedState); + } + + bool haveProxy = false; + bool haveHTTPSProxy = false; + if (proxy) { + nsAutoCString proxyHost; + proxy->GetHost(proxyHost); + haveProxy = !proxyHost.IsEmpty(); + nsAutoCString type; + haveHTTPSProxy = haveProxy && NS_SUCCEEDED(proxy->GetType(type)) && + type.EqualsLiteral("https"); + } + + // A plaintext observer shim is inserted so we can observe some protocol + // details without modifying nss + plaintextLayer = + PR_CreateIOLayerStub(nsSSLIOLayerHelpers::nsSSLPlaintextLayerIdentity, + &nsSSLIOLayerHelpers::nsSSLPlaintextLayerMethods); + if (plaintextLayer) { + plaintextLayer->secret = (PRFilePrivate*)infoObject; + stat = PR_PushIOLayer(fd, PR_TOP_IO_LAYER, plaintextLayer); + if (stat == PR_FAILURE) { + plaintextLayer->dtor(plaintextLayer); + plaintextLayer = nullptr; + } + } + + PRFileDesc* sslSock = + nsSSLIOLayerImportFD(fd, infoObject, host, haveHTTPSProxy); + if (!sslSock) { + MOZ_ASSERT_UNREACHABLE("NSS: Error importing socket"); + goto loser; + } + + infoObject->SetFileDescPtr(sslSock); + + rv = nsSSLIOLayerSetOptions(sslSock, forSTARTTLS, haveProxy, host, port, + infoObject); + + if (NS_FAILED(rv)) goto loser; + + // Now, layer ourselves on top of the SSL socket... + layer = PR_CreateIOLayerStub(nsSSLIOLayerHelpers::nsSSLIOLayerIdentity, + &nsSSLIOLayerHelpers::nsSSLIOLayerMethods); + if (!layer) goto loser; + + layer->secret = (PRFilePrivate*)infoObject; + stat = PR_PushIOLayer(sslSock, PR_GetLayersIdentity(sslSock), layer); + + if (stat == PR_FAILURE) { + goto loser; + } + + MOZ_LOG(gPIPNSSLog, LogLevel::Debug, ("[%p] Socket set up", (void*)sslSock)); + *tlsSocketControl = do_AddRef(infoObject).take(); + + // We are going use a clear connection first // + if (forSTARTTLS || haveProxy) { + infoObject->SetHandshakeNotPending(); + } + + infoObject->SharedState().NoteSocketCreated(); + + rv = infoObject->SetResumptionTokenFromExternalCache(); + if (NS_FAILED(rv)) { + return rv; + } + SSL_SetResumptionTokenCallback(sslSock, &StoreResumptionToken, infoObject); + + return NS_OK; +loser: + NS_IF_RELEASE(infoObject); + if (layer) { + layer->dtor(layer); + } + if (plaintextLayer) { + // Note that PR_*IOLayer operations may modify the stack of fds, so a + // previously-valid pointer may no longer point to what we think it points + // to after calling PR_PopIOLayer. We must operate on the pointer returned + // by PR_PopIOLayer. + plaintextLayer = + PR_PopIOLayer(fd, nsSSLIOLayerHelpers::nsSSLPlaintextLayerIdentity); + plaintextLayer->dtor(plaintextLayer); + } + return NS_ERROR_FAILURE; +} + +already_AddRefed<IPCClientCertsChild> GetIPCClientCertsActor() { + PBackgroundChild* backgroundActor = + BackgroundChild::GetOrCreateForSocketParentBridgeForCurrentThread(); + if (!backgroundActor) { + return nullptr; + } + RefPtr<PIPCClientCertsChild> actor = + SingleManagedOrNull(backgroundActor->ManagedPIPCClientCertsChild()); + if (!actor) { + actor = backgroundActor->SendPIPCClientCertsConstructor( + new IPCClientCertsChild()); + if (!actor) { + return nullptr; + } + } + return actor.forget().downcast<IPCClientCertsChild>(); +} + +extern "C" { + +const uint8_t kIPCClientCertsObjectTypeCert = 1; +const uint8_t kIPCClientCertsObjectTypeRSAKey = 2; +const uint8_t kIPCClientCertsObjectTypeECKey = 3; + +// This function is provided to the IPC client certs module so it can cause the +// parent process to find certificates and keys and send identifying +// information about them over IPC. +void DoFindObjects(FindObjectsCallback cb, void* ctx) { + RefPtr<IPCClientCertsChild> ipcClientCertsActor(GetIPCClientCertsActor()); + if (!ipcClientCertsActor) { + return; + } + nsTArray<IPCClientCertObject> objects; + if (!ipcClientCertsActor->SendFindObjects(&objects)) { + return; + } + for (const auto& object : objects) { + switch (object.type()) { + case IPCClientCertObject::TECKey: + cb(kIPCClientCertsObjectTypeECKey, object.get_ECKey().params().Length(), + object.get_ECKey().params().Elements(), + object.get_ECKey().cert().Length(), + object.get_ECKey().cert().Elements(), object.get_ECKey().slotType(), + ctx); + break; + case IPCClientCertObject::TRSAKey: + cb(kIPCClientCertsObjectTypeRSAKey, + object.get_RSAKey().modulus().Length(), + object.get_RSAKey().modulus().Elements(), + object.get_RSAKey().cert().Length(), + object.get_RSAKey().cert().Elements(), + object.get_RSAKey().slotType(), ctx); + break; + case IPCClientCertObject::TCertificate: + cb(kIPCClientCertsObjectTypeCert, + object.get_Certificate().der().Length(), + object.get_Certificate().der().Elements(), 0, nullptr, + object.get_Certificate().slotType(), ctx); + break; + default: + MOZ_ASSERT_UNREACHABLE("unhandled IPCClientCertObject type"); + break; + } + } +} + +// This function is provided to the IPC client certs module so it can cause the +// parent process to sign the given data using the key corresponding to the +// given certificate, using the given parameters. +void DoSign(size_t cert_len, const uint8_t* cert, size_t data_len, + const uint8_t* data, size_t params_len, const uint8_t* params, + SignCallback cb, void* ctx) { + RefPtr<IPCClientCertsChild> ipcClientCertsActor(GetIPCClientCertsActor()); + if (!ipcClientCertsActor) { + return; + } + ByteArray certBytes(nsTArray<uint8_t>(cert, cert_len)); + ByteArray dataBytes(nsTArray<uint8_t>(data, data_len)); + ByteArray paramsBytes(nsTArray<uint8_t>(params, params_len)); + ByteArray signature; + if (!ipcClientCertsActor->SendSign(certBytes, dataBytes, paramsBytes, + &signature)) { + return; + } + cb(signature.data().Length(), signature.data().Elements(), ctx); +} +} // extern "C" |