/* * * Copyright (C) 2017 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include #include #include #include #include #include #include #include #include #include #define __STDC_FORMAT_MACROS #include #include #include #include #include #include #include #include #include #include #include #include #define LOG_TAG "XfrmController" #include #include #include #include #include #include #include #include #include "Fwmark.h" #include "InterfaceController.h" #include "NetdConstants.h" #include "NetlinkCommands.h" #include "Permission.h" #include "XfrmController.h" #include "android-base/stringprintf.h" #include "android-base/strings.h" #include "android-base/unique_fd.h" #include "netdutils/DumpWriter.h" #include "netdutils/Fd.h" #include "netdutils/Slice.h" #include "netdutils/Syscalls.h" using android::net::INetd; using android::netdutils::DumpWriter; using android::netdutils::Fd; using android::netdutils::ScopedIndent; using android::netdutils::Slice; using android::netdutils::Status; using android::netdutils::StatusOr; using android::netdutils::Syscalls; namespace android { namespace net { // Exposed for testing constexpr uint32_t ALGO_MASK_AUTH_ALL = ~0; // Exposed for testing constexpr uint32_t ALGO_MASK_CRYPT_ALL = ~0; // Exposed for testing constexpr uint32_t ALGO_MASK_AEAD_ALL = ~0; // Exposed for testing constexpr uint8_t REPLAY_WINDOW_SIZE = 32; namespace { constexpr uint32_t RAND_SPI_MIN = 256; constexpr uint32_t RAND_SPI_MAX = 0xFFFFFFFE; constexpr uint32_t INVALID_SPI = 0; constexpr const char* INFO_KIND_VTI = "vti"; constexpr const char* INFO_KIND_VTI6 = "vti6"; constexpr const char* INFO_KIND_XFRMI = "xfrm"; constexpr int INFO_KIND_MAX_LEN = 8; constexpr int LOOPBACK_IFINDEX = 1; bool mIsXfrmIntfSupported = false; static inline bool isEngBuild() { static const std::string sBuildType = android::base::GetProperty("ro.build.type", "user"); return sBuildType == "eng"; } #define XFRM_MSG_TRANS(x) \ case x: \ return #x; const char* xfrmMsgTypeToString(uint16_t msg) { switch (msg) { XFRM_MSG_TRANS(XFRM_MSG_NEWSA) XFRM_MSG_TRANS(XFRM_MSG_DELSA) XFRM_MSG_TRANS(XFRM_MSG_GETSA) XFRM_MSG_TRANS(XFRM_MSG_NEWPOLICY) XFRM_MSG_TRANS(XFRM_MSG_DELPOLICY) XFRM_MSG_TRANS(XFRM_MSG_GETPOLICY) XFRM_MSG_TRANS(XFRM_MSG_ALLOCSPI) XFRM_MSG_TRANS(XFRM_MSG_ACQUIRE) XFRM_MSG_TRANS(XFRM_MSG_EXPIRE) XFRM_MSG_TRANS(XFRM_MSG_UPDPOLICY) XFRM_MSG_TRANS(XFRM_MSG_UPDSA) XFRM_MSG_TRANS(XFRM_MSG_POLEXPIRE) XFRM_MSG_TRANS(XFRM_MSG_FLUSHSA) XFRM_MSG_TRANS(XFRM_MSG_FLUSHPOLICY) XFRM_MSG_TRANS(XFRM_MSG_NEWAE) XFRM_MSG_TRANS(XFRM_MSG_GETAE) XFRM_MSG_TRANS(XFRM_MSG_REPORT) XFRM_MSG_TRANS(XFRM_MSG_MIGRATE) XFRM_MSG_TRANS(XFRM_MSG_NEWSADINFO) XFRM_MSG_TRANS(XFRM_MSG_GETSADINFO) XFRM_MSG_TRANS(XFRM_MSG_GETSPDINFO) XFRM_MSG_TRANS(XFRM_MSG_NEWSPDINFO) XFRM_MSG_TRANS(XFRM_MSG_MAPPING) default: return "XFRM_MSG UNKNOWN"; } } // actually const but cannot be declared as such for reasons uint8_t kPadBytesArray[] = {0, 0, 0}; void* kPadBytes = static_cast(kPadBytesArray); #define LOG_HEX(__desc16__, __buf__, __len__) \ do { \ if (isEngBuild()) { \ logHex(__desc16__, __buf__, __len__); \ } \ } while (0) #define LOG_IOV(__iov__) \ do { \ if (isEngBuild()) { \ logIov(__iov__); \ } \ } while (0) void logHex(const char* desc16, const char* buf, size_t len) { char* printBuf = new char[len * 2 + 1 + 26]; // len->ascii, +newline, +prefix strlen int offset = 0; if (desc16) { sprintf(printBuf, "{%-16s}", desc16); offset += 18; // prefix string length } sprintf(printBuf + offset, "[%4.4u]: ", (len > 9999) ? 9999 : (unsigned)len); offset += 8; for (uint32_t j = 0; j < (uint32_t)len; j++) { sprintf(&printBuf[j * 2 + offset], "%0.2x", (unsigned char)buf[j]); } ALOGD("%s", printBuf); delete[] printBuf; } void logIov(const std::vector& iov) { for (const iovec& row : iov) { logHex(nullptr, reinterpret_cast(row.iov_base), row.iov_len); } } size_t fillNlAttr(__u16 nlaType, size_t valueSize, nlattr* nlAttr) { size_t dataLen = valueSize; int padLength = NLMSG_ALIGN(dataLen) - dataLen; nlAttr->nla_len = (__u16)(dataLen + sizeof(nlattr)); nlAttr->nla_type = nlaType; return padLength; } size_t fillNlAttrIpAddress(__u16 nlaType, int family, const std::string& value, nlattr* nlAttr, Slice ipAddress) { inet_pton(family, value.c_str(), ipAddress.base()); return fillNlAttr(nlaType, (family == AF_INET) ? sizeof(in_addr) : sizeof(in6_addr), nlAttr); } size_t fillNlAttrU32(__u16 nlaType, uint32_t value, XfrmController::nlattr_payload_u32* nlAttr) { nlAttr->value = value; return fillNlAttr(nlaType, sizeof(value), &nlAttr->hdr); } // returns the address family, placing the string in the provided buffer StatusOr convertStringAddress(const std::string& addr, uint8_t* buffer) { if (inet_pton(AF_INET, addr.c_str(), buffer) == 1) { return AF_INET; } else if (inet_pton(AF_INET6, addr.c_str(), buffer) == 1) { return AF_INET6; } else { return Status(EAFNOSUPPORT); } } // TODO: Need to consider a way to refer to the sSycalls instance inline Syscalls& getSyscallInstance() { return netdutils::sSyscalls.get(); } class XfrmSocketImpl : public XfrmSocket { private: static constexpr int NLMSG_DEFAULTSIZE = 8192; union NetlinkResponse { nlmsghdr hdr; struct _err_ { nlmsghdr hdr; nlmsgerr err; } err; struct _buf_ { nlmsghdr hdr; char buf[NLMSG_DEFAULTSIZE]; } buf; }; public: netdutils::Status open() override { mSock = openNetlinkSocket(NETLINK_XFRM); if (mSock < 0) { ALOGW("Could not get a new socket, line=%d", __LINE__); return netdutils::statusFromErrno(-mSock, "Could not open netlink socket"); } return netdutils::status::ok; } static netdutils::Status validateResponse(NetlinkResponse response, size_t len) { if (len < sizeof(nlmsghdr)) { ALOGW("Invalid response message received over netlink"); return netdutils::statusFromErrno(EBADMSG, "Invalid message"); } switch (response.hdr.nlmsg_type) { case NLMSG_NOOP: case NLMSG_DONE: return netdutils::status::ok; case NLMSG_OVERRUN: ALOGD("Netlink request overran kernel buffer"); return netdutils::statusFromErrno(EBADMSG, "Kernel buffer overrun"); case NLMSG_ERROR: if (len < sizeof(NetlinkResponse::_err_)) { ALOGD("Netlink message received malformed error response"); return netdutils::statusFromErrno(EBADMSG, "Malformed error response"); } return netdutils::statusFromErrno( -response.err.err.error, "Error netlink message"); // Netlink errors are negative errno. case XFRM_MSG_NEWSA: break; } if (response.hdr.nlmsg_type < XFRM_MSG_BASE /*== NLMSG_MIN_TYPE*/ || response.hdr.nlmsg_type > XFRM_MSG_MAX) { ALOGD("Netlink message responded with an out-of-range message ID"); return netdutils::statusFromErrno(EBADMSG, "Invalid message ID"); } // TODO Add more message validation here return netdutils::status::ok; } netdutils::Status sendMessage(uint16_t nlMsgType, uint16_t nlMsgFlags, uint16_t nlMsgSeqNum, std::vector* iovecs) const override { nlmsghdr nlMsg = { .nlmsg_type = nlMsgType, .nlmsg_flags = nlMsgFlags, .nlmsg_seq = nlMsgSeqNum, }; (*iovecs)[0].iov_base = &nlMsg; (*iovecs)[0].iov_len = NLMSG_HDRLEN; for (const iovec& iov : *iovecs) { nlMsg.nlmsg_len += iov.iov_len; } ALOGD("Sending Netlink XFRM Message: %s", xfrmMsgTypeToString(nlMsgType)); LOG_IOV(*iovecs); StatusOr writeResult = getSyscallInstance().writev(mSock, *iovecs); if (!isOk(writeResult)) { ALOGE("netlink socket writev failed (%s)", toString(writeResult).c_str()); return writeResult; } if (nlMsg.nlmsg_len != writeResult.value()) { ALOGE("Invalid netlink message length sent %d", static_cast(writeResult.value())); return netdutils::statusFromErrno(EBADMSG, "Invalid message length"); } NetlinkResponse response = {}; StatusOr readResult = getSyscallInstance().read(Fd(mSock), netdutils::makeSlice(response)); if (!isOk(readResult)) { ALOGE("netlink response error (%s)", toString(readResult).c_str()); return readResult; } LOG_HEX("netlink msg resp", reinterpret_cast(readResult.value().base()), readResult.value().size()); Status validateStatus = validateResponse(response, readResult.value().size()); if (!isOk(validateStatus)) { ALOGE("netlink response contains error (%s)", toString(validateStatus).c_str()); } return validateStatus; } }; StatusOr convertToXfrmAddr(const std::string& strAddr, xfrm_address_t* xfrmAddr) { if (strAddr.length() == 0) { memset(xfrmAddr, 0, sizeof(*xfrmAddr)); return AF_UNSPEC; } if (inet_pton(AF_INET6, strAddr.c_str(), reinterpret_cast(xfrmAddr))) { return AF_INET6; } else if (inet_pton(AF_INET, strAddr.c_str(), reinterpret_cast(xfrmAddr))) { return AF_INET; } else { return netdutils::statusFromErrno(EAFNOSUPPORT, "Invalid address family"); } } void fillXfrmNlaHdr(nlattr* hdr, uint16_t type, uint16_t len) { hdr->nla_type = type; hdr->nla_len = len; } void fillXfrmCurLifetimeDefaults(xfrm_lifetime_cur* cur) { memset(reinterpret_cast(cur), 0, sizeof(*cur)); } void fillXfrmLifetimeDefaults(xfrm_lifetime_cfg* cfg) { cfg->soft_byte_limit = XFRM_INF; cfg->hard_byte_limit = XFRM_INF; cfg->soft_packet_limit = XFRM_INF; cfg->hard_packet_limit = XFRM_INF; } /* * Allocate SPIs within an (inclusive) range of min-max. * returns 0 (INVALID_SPI) once the entire range has been parsed. */ class RandomSpi { public: RandomSpi(int min, int max) : mMin(min) { // Re-seeding should be safe because the seed itself is // sufficiently random and we don't need secure random std::mt19937 rnd = std::mt19937(std::random_device()()); mNext = std::uniform_int_distribution<>(1, INT_MAX)(rnd); mSize = max - min + 1; mCount = mSize; } uint32_t next() { if (!mCount) return 0; mCount--; return (mNext++ % mSize) + mMin; } private: uint32_t mNext; uint32_t mSize; uint32_t mMin; uint32_t mCount; }; } // namespace // // Begin XfrmController Impl // // XfrmController::XfrmController(void) {} // Test-only constructor allowing override of XFRM Interface support checks XfrmController::XfrmController(bool xfrmIntfSupport) { mIsXfrmIntfSupported = xfrmIntfSupport; } netdutils::Status XfrmController::Init() { RETURN_IF_NOT_OK(flushInterfaces()); mIsXfrmIntfSupported = isXfrmIntfSupported(); XfrmSocketImpl sock; RETURN_IF_NOT_OK(sock.open()); RETURN_IF_NOT_OK(flushSaDb(sock)); return flushPolicyDb(sock); } netdutils::Status XfrmController::flushInterfaces() { const auto& ifaces = InterfaceController::getIfaceNames(); RETURN_IF_NOT_OK(ifaces); const String8 ifPrefix8 = String8(INetd::IPSEC_INTERFACE_PREFIX().string()); for (const std::string& iface : ifaces.value()) { netdutils::Status status; // Look for the reserved interface prefix, which must be in the name at position 0 if (android::base::StartsWith(iface.c_str(), ifPrefix8.c_str())) { RETURN_IF_NOT_OK(ipSecRemoveTunnelInterface(iface)); } } return netdutils::status::ok; } netdutils::Status XfrmController::flushSaDb(const XfrmSocket& s) { struct xfrm_usersa_flush flushUserSa = {.proto = IPSEC_PROTO_ANY}; std::vector iov = {{nullptr, 0}, // reserved for the eventual addition of a NLMSG_HDR {&flushUserSa, sizeof(flushUserSa)}, // xfrm_usersa_flush structure {kPadBytes, NLMSG_ALIGN(sizeof(flushUserSa)) - sizeof(flushUserSa)}}; return s.sendMessage(XFRM_MSG_FLUSHSA, NETLINK_REQUEST_FLAGS, 0, &iov); } netdutils::Status XfrmController::flushPolicyDb(const XfrmSocket& s) { std::vector iov = {{nullptr, 0}}; // reserved for the eventual addition of a NLMSG_HDR return s.sendMessage(XFRM_MSG_FLUSHPOLICY, NETLINK_REQUEST_FLAGS, 0, &iov); } bool XfrmController::isXfrmIntfSupported() { const char* IPSEC_TEST_INTF_NAME = "ipsec_test"; const int32_t XFRM_TEST_IF_ID = 0xFFFF; bool errored = false; errored |= ipSecAddXfrmInterface(IPSEC_TEST_INTF_NAME, XFRM_TEST_IF_ID, NETLINK_ROUTE_CREATE_FLAGS) .code(); errored |= ipSecRemoveTunnelInterface(IPSEC_TEST_INTF_NAME).code(); return !errored; } netdutils::Status XfrmController::ipSecSetEncapSocketOwner(int socketFd, int newUid, uid_t callerUid) { ALOGD("XfrmController:%s, line=%d", __FUNCTION__, __LINE__); const int fd = socketFd; struct stat info; if (fstat(fd, &info)) { return netdutils::statusFromErrno(errno, "Failed to stat socket file descriptor"); } if (info.st_uid != callerUid) { return netdutils::statusFromErrno(EPERM, "fchown disabled for non-owner calls"); } if (S_ISSOCK(info.st_mode) == 0) { return netdutils::statusFromErrno(EINVAL, "File descriptor was not a socket"); } int optval; socklen_t optlen = sizeof(optval); netdutils::Status status = getSyscallInstance().getsockopt(Fd(fd), IPPROTO_UDP, UDP_ENCAP, &optval, &optlen); if (status != netdutils::status::ok) { return status; } if (optval != UDP_ENCAP_ESPINUDP && optval != UDP_ENCAP_ESPINUDP_NON_IKE) { return netdutils::statusFromErrno(EINVAL, "Socket did not have UDP-encap sockopt set"); } if (fchown(fd, newUid, -1)) { return netdutils::statusFromErrno(errno, "Failed to fchown socket file descriptor"); } return netdutils::status::ok; } netdutils::Status XfrmController::ipSecAllocateSpi(int32_t transformId, const std::string& sourceAddress, const std::string& destinationAddress, int32_t inSpi, int32_t* outSpi) { ALOGD("XfrmController:%s, line=%d", __FUNCTION__, __LINE__); ALOGD("transformId=%d", transformId); ALOGD("sourceAddress=%s", sourceAddress.c_str()); ALOGD("destinationAddress=%s", destinationAddress.c_str()); ALOGD("inSpi=%0.8x", inSpi); XfrmSaInfo saInfo{}; netdutils::Status ret = fillXfrmCommonInfo(sourceAddress, destinationAddress, INVALID_SPI, 0, 0, transformId, 0, &saInfo); if (!isOk(ret)) { return ret; } XfrmSocketImpl sock; netdutils::Status socketStatus = sock.open(); if (!isOk(socketStatus)) { ALOGD("Sock open failed for XFRM, line=%d", __LINE__); return socketStatus; } int minSpi = RAND_SPI_MIN, maxSpi = RAND_SPI_MAX; if (inSpi) minSpi = maxSpi = inSpi; ret = allocateSpi(saInfo, minSpi, maxSpi, reinterpret_cast(outSpi), sock); if (!isOk(ret)) { // TODO: May want to return a new Status with a modified status string ALOGD("Failed to Allocate an SPI, line=%d", __LINE__); *outSpi = INVALID_SPI; } return ret; } netdutils::Status XfrmController::ipSecAddSecurityAssociation( int32_t transformId, int32_t mode, const std::string& sourceAddress, const std::string& destinationAddress, int32_t underlyingNetId, int32_t spi, int32_t markValue, int32_t markMask, const std::string& authAlgo, const std::vector& authKey, int32_t authTruncBits, const std::string& cryptAlgo, const std::vector& cryptKey, int32_t cryptTruncBits, const std::string& aeadAlgo, const std::vector& aeadKey, int32_t aeadIcvBits, int32_t encapType, int32_t encapLocalPort, int32_t encapRemotePort, int32_t xfrmInterfaceId) { ALOGD("XfrmController::%s, line=%d", __FUNCTION__, __LINE__); ALOGD("transformId=%d", transformId); ALOGD("mode=%d", mode); ALOGD("sourceAddress=%s", sourceAddress.c_str()); ALOGD("destinationAddress=%s", destinationAddress.c_str()); ALOGD("underlyingNetworkId=%d", underlyingNetId); ALOGD("spi=%0.8x", spi); ALOGD("markValue=%x", markValue); ALOGD("markMask=%x", markMask); ALOGD("authAlgo=%s", authAlgo.c_str()); ALOGD("authTruncBits=%d", authTruncBits); ALOGD("cryptAlgo=%s", cryptAlgo.c_str()); ALOGD("cryptTruncBits=%d,", cryptTruncBits); ALOGD("aeadAlgo=%s", aeadAlgo.c_str()); ALOGD("aeadIcvBits=%d,", aeadIcvBits); ALOGD("encapType=%d", encapType); ALOGD("encapLocalPort=%d", encapLocalPort); ALOGD("encapRemotePort=%d", encapRemotePort); ALOGD("xfrmInterfaceId=%d", xfrmInterfaceId); XfrmSaInfo saInfo{}; netdutils::Status ret = fillXfrmCommonInfo(sourceAddress, destinationAddress, spi, markValue, markMask, transformId, xfrmInterfaceId, &saInfo); if (!isOk(ret)) { return ret; } saInfo.auth = XfrmAlgo{ .name = authAlgo, .key = authKey, .truncLenBits = static_cast(authTruncBits)}; saInfo.crypt = XfrmAlgo{ .name = cryptAlgo, .key = cryptKey, .truncLenBits = static_cast(cryptTruncBits)}; saInfo.aead = XfrmAlgo{ .name = aeadAlgo, .key = aeadKey, .truncLenBits = static_cast(aeadIcvBits)}; switch (static_cast(mode)) { case XfrmMode::TRANSPORT: case XfrmMode::TUNNEL: saInfo.mode = static_cast(mode); break; default: return netdutils::statusFromErrno(EINVAL, "Invalid xfrm mode"); } XfrmSocketImpl sock; netdutils::Status socketStatus = sock.open(); if (!isOk(socketStatus)) { ALOGD("Sock open failed for XFRM, line=%d", __LINE__); return socketStatus; } switch (static_cast(encapType)) { case XfrmEncapType::ESPINUDP: case XfrmEncapType::ESPINUDP_NON_IKE: if (saInfo.addrFamily != AF_INET) { return netdutils::statusFromErrno(EAFNOSUPPORT, "IPv6 encap not supported"); } // The ports are not used on input SAs, so this is OK to be wrong when // direction is ultimately input. saInfo.encap.srcPort = encapLocalPort; saInfo.encap.dstPort = encapRemotePort; [[fallthrough]]; case XfrmEncapType::NONE: saInfo.encap.type = static_cast(encapType); break; default: return netdutils::statusFromErrno(EINVAL, "Invalid encap type"); } saInfo.netId = underlyingNetId; ret = updateSecurityAssociation(saInfo, sock); if (!isOk(ret)) { ALOGD("Failed updating a Security Association, line=%d", __LINE__); } return ret; } netdutils::Status XfrmController::ipSecDeleteSecurityAssociation( int32_t transformId, const std::string& sourceAddress, const std::string& destinationAddress, int32_t spi, int32_t markValue, int32_t markMask, int32_t xfrmInterfaceId) { ALOGD("XfrmController:%s, line=%d", __FUNCTION__, __LINE__); ALOGD("transformId=%d", transformId); ALOGD("sourceAddress=%s", sourceAddress.c_str()); ALOGD("destinationAddress=%s", destinationAddress.c_str()); ALOGD("spi=%0.8x", spi); ALOGD("markValue=%x", markValue); ALOGD("markMask=%x", markMask); ALOGD("xfrmInterfaceId=%d", xfrmInterfaceId); XfrmSaInfo saInfo{}; netdutils::Status ret = fillXfrmCommonInfo(sourceAddress, destinationAddress, spi, markValue, markMask, transformId, xfrmInterfaceId, &saInfo); if (!isOk(ret)) { return ret; } XfrmSocketImpl sock; netdutils::Status socketStatus = sock.open(); if (!isOk(socketStatus)) { ALOGD("Sock open failed for XFRM, line=%d", __LINE__); return socketStatus; } ret = deleteSecurityAssociation(saInfo, sock); if (!isOk(ret)) { ALOGD("Failed to delete Security Association, line=%d", __LINE__); } return ret; } netdutils::Status XfrmController::fillXfrmCommonInfo(const std::string& sourceAddress, const std::string& destinationAddress, int32_t spi, int32_t markValue, int32_t markMask, int32_t transformId, int32_t xfrmInterfaceId, XfrmCommonInfo* info) { // Use the addresses to determine the address family and do validation xfrm_address_t sourceXfrmAddr{}, destXfrmAddr{}; StatusOr sourceFamily, destFamily; sourceFamily = convertToXfrmAddr(sourceAddress, &sourceXfrmAddr); destFamily = convertToXfrmAddr(destinationAddress, &destXfrmAddr); if (!isOk(sourceFamily) || !isOk(destFamily)) { return netdutils::statusFromErrno(EINVAL, "Invalid address " + sourceAddress + "/" + destinationAddress); } if (destFamily.value() == AF_UNSPEC || (sourceFamily.value() != AF_UNSPEC && sourceFamily.value() != destFamily.value())) { ALOGD("Invalid or Mismatched Address Families, %d != %d, line=%d", sourceFamily.value(), destFamily.value(), __LINE__); return netdutils::statusFromErrno(EINVAL, "Invalid or mismatched address families"); } info->addrFamily = destFamily.value(); info->dstAddr = destXfrmAddr; info->srcAddr = sourceXfrmAddr; return fillXfrmCommonInfo(spi, markValue, markMask, transformId, xfrmInterfaceId, info); } netdutils::Status XfrmController::fillXfrmCommonInfo(int32_t spi, int32_t markValue, int32_t markMask, int32_t transformId, int32_t xfrmInterfaceId, XfrmCommonInfo* info) { info->transformId = transformId; info->spi = htonl(spi); if (mIsXfrmIntfSupported) { info->xfrm_if_id = xfrmInterfaceId; } else { info->mark.v = markValue; info->mark.m = markMask; } return netdutils::status::ok; } netdutils::Status XfrmController::ipSecApplyTransportModeTransform( int socketFd, int32_t transformId, int32_t direction, const std::string& sourceAddress, const std::string& destinationAddress, int32_t spi) { ALOGD("XfrmController::%s, line=%d", __FUNCTION__, __LINE__); ALOGD("transformId=%d", transformId); ALOGD("direction=%d", direction); ALOGD("sourceAddress=%s", sourceAddress.c_str()); ALOGD("destinationAddress=%s", destinationAddress.c_str()); ALOGD("spi=%0.8x", spi); StatusOr ret = getSyscallInstance().getsockname(Fd(socketFd)); if (!isOk(ret)) { ALOGE("Failed to get socket info in %s", __FUNCTION__); return ret; } struct sockaddr_storage saddr = ret.value(); XfrmSpInfo spInfo{}; netdutils::Status status = fillXfrmCommonInfo(sourceAddress, destinationAddress, spi, 0, 0, transformId, 0, &spInfo); if (!isOk(status)) { ALOGE("Couldn't build SA ID %s", __FUNCTION__); return status; } spInfo.selAddrFamily = spInfo.addrFamily; // Allow dual stack sockets. Dual stack sockets are guaranteed to never have an AF_INET source // address; the source address would instead be an IPv4-mapped address. Thus, disallow AF_INET // sockets with mismatched address families (All other cases are acceptable). if (saddr.ss_family == AF_INET && spInfo.addrFamily != AF_INET) { ALOGE("IPV4 socket address family(%d) should match IPV4 Transform " "address family(%d)!", saddr.ss_family, spInfo.addrFamily); return netdutils::statusFromErrno(EINVAL, "Mismatched address family"); } struct { xfrm_userpolicy_info info; xfrm_user_tmpl tmpl; } policy{}; fillUserSpInfo(spInfo, static_cast(direction), &policy.info); fillUserTemplate(spInfo, &policy.tmpl); LOG_HEX("XfrmUserPolicy", reinterpret_cast(&policy), sizeof(policy)); int sockOpt, sockLayer; switch (saddr.ss_family) { case AF_INET: sockOpt = IP_XFRM_POLICY; sockLayer = SOL_IP; break; case AF_INET6: sockOpt = IPV6_XFRM_POLICY; sockLayer = SOL_IPV6; break; default: return netdutils::statusFromErrno(EAFNOSUPPORT, "Invalid address family"); } status = getSyscallInstance().setsockopt(Fd(socketFd), sockLayer, sockOpt, policy); if (!isOk(status)) { ALOGE("Error setting socket option for XFRM! (%s)", toString(status).c_str()); } return status; } netdutils::Status XfrmController::ipSecRemoveTransportModeTransform(int socketFd) { ALOGD("XfrmController::%s, line=%d", __FUNCTION__, __LINE__); StatusOr ret = getSyscallInstance().getsockname(Fd(socketFd)); if (!isOk(ret)) { ALOGE("Failed to get socket info in %s! (%s)", __FUNCTION__, toString(ret).c_str()); return ret; } int sockOpt, sockLayer; switch (ret.value().ss_family) { case AF_INET: sockOpt = IP_XFRM_POLICY; sockLayer = SOL_IP; break; case AF_INET6: sockOpt = IPV6_XFRM_POLICY; sockLayer = SOL_IPV6; break; default: return netdutils::statusFromErrno(EAFNOSUPPORT, "Invalid address family"); } // Kernel will delete the security policy on this socket for both direction // if optval is set to NULL and optlen is set to 0. netdutils::Status status = getSyscallInstance().setsockopt(Fd(socketFd), sockLayer, sockOpt, nullptr, 0); if (!isOk(status)) { ALOGE("Error removing socket option for XFRM! (%s)", toString(status).c_str()); } return status; } netdutils::Status XfrmController::ipSecAddSecurityPolicy( int32_t transformId, int32_t selAddrFamily, int32_t direction, const std::string& tmplSrcAddress, const std::string& tmplDstAddress, int32_t spi, int32_t markValue, int32_t markMask, int32_t xfrmInterfaceId) { return processSecurityPolicy(transformId, selAddrFamily, direction, tmplSrcAddress, tmplDstAddress, spi, markValue, markMask, xfrmInterfaceId, XFRM_MSG_NEWPOLICY); } netdutils::Status XfrmController::ipSecUpdateSecurityPolicy( int32_t transformId, int32_t selAddrFamily, int32_t direction, const std::string& tmplSrcAddress, const std::string& tmplDstAddress, int32_t spi, int32_t markValue, int32_t markMask, int32_t xfrmInterfaceId) { return processSecurityPolicy(transformId, selAddrFamily, direction, tmplSrcAddress, tmplDstAddress, spi, markValue, markMask, xfrmInterfaceId, XFRM_MSG_UPDPOLICY); } netdutils::Status XfrmController::ipSecDeleteSecurityPolicy(int32_t transformId, int32_t selAddrFamily, int32_t direction, int32_t markValue, int32_t markMask, int32_t xfrmInterfaceId) { return processSecurityPolicy(transformId, selAddrFamily, direction, "", "", 0, markValue, markMask, xfrmInterfaceId, XFRM_MSG_DELPOLICY); } netdutils::Status XfrmController::processSecurityPolicy( int32_t transformId, int32_t selAddrFamily, int32_t direction, const std::string& tmplSrcAddress, const std::string& tmplDstAddress, int32_t spi, int32_t markValue, int32_t markMask, int32_t xfrmInterfaceId, int32_t msgType) { ALOGD("XfrmController::%s, line=%d", __FUNCTION__, __LINE__); ALOGD("selAddrFamily=%s", selAddrFamily == AF_INET6 ? "AF_INET6" : "AF_INET"); ALOGD("transformId=%d", transformId); ALOGD("direction=%d", direction); ALOGD("tmplSrcAddress=%s", tmplSrcAddress.c_str()); ALOGD("tmplDstAddress=%s", tmplDstAddress.c_str()); ALOGD("spi=%0.8x", spi); ALOGD("markValue=%d", markValue); ALOGD("markMask=%d", markMask); ALOGD("msgType=%d", msgType); ALOGD("xfrmInterfaceId=%d", xfrmInterfaceId); XfrmSpInfo spInfo{}; spInfo.mode = XfrmMode::TUNNEL; XfrmSocketImpl sock; RETURN_IF_NOT_OK(sock.open()); // Set the correct address families. Tunnel mode policies use wildcard selectors, while // templates have addresses set. These may be different address families. This method is called // separately for IPv4 and IPv6 policies, and thus only need to map a single inner address // family to the outer address families. spInfo.selAddrFamily = selAddrFamily; if (msgType == XFRM_MSG_DELPOLICY) { RETURN_IF_NOT_OK(fillXfrmCommonInfo(spi, markValue, markMask, transformId, xfrmInterfaceId, &spInfo)); return deleteTunnelModeSecurityPolicy(spInfo, sock, static_cast(direction)); } else { RETURN_IF_NOT_OK(fillXfrmCommonInfo(tmplSrcAddress, tmplDstAddress, spi, markValue, markMask, transformId, xfrmInterfaceId, &spInfo)); return updateTunnelModeSecurityPolicy(spInfo, sock, static_cast(direction), msgType); } } void XfrmController::fillXfrmSelector(const int selAddrFamily, xfrm_selector* selector) { selector->family = selAddrFamily; selector->proto = AF_UNSPEC; // TODO: do we need to match the protocol? it's // possible via the socket } netdutils::Status XfrmController::updateSecurityAssociation(const XfrmSaInfo& record, const XfrmSocket& sock) { xfrm_usersa_info usersa{}; nlattr_algo_crypt crypt{}; nlattr_algo_auth auth{}; nlattr_algo_aead aead{}; nlattr_xfrm_mark xfrmmark{}; nlattr_xfrm_output_mark xfrmoutputmark{}; nlattr_encap_tmpl encap{}; nlattr_xfrm_interface_id xfrm_if_id{}; enum { NLMSG_HDR, USERSA, USERSA_PAD, CRYPT, CRYPT_PAD, AUTH, AUTH_PAD, AEAD, AEAD_PAD, MARK, MARK_PAD, OUTPUT_MARK, OUTPUT_MARK_PAD, ENCAP, ENCAP_PAD, INTF_ID, INTF_ID_PAD, }; std::vector iov = { {nullptr, 0}, // reserved for the eventual addition of a NLMSG_HDR {&usersa, 0}, // main usersa_info struct {kPadBytes, 0}, // up to NLMSG_ALIGNTO pad bytes of padding {&crypt, 0}, // adjust size if crypt algo is present {kPadBytes, 0}, // up to NLATTR_ALIGNTO pad bytes {&auth, 0}, // adjust size if auth algo is present {kPadBytes, 0}, // up to NLATTR_ALIGNTO pad bytes {&aead, 0}, // adjust size if aead algo is present {kPadBytes, 0}, // up to NLATTR_ALIGNTO pad bytes {&xfrmmark, 0}, // adjust size if xfrm mark is present {kPadBytes, 0}, // up to NLATTR_ALIGNTO pad bytes {&xfrmoutputmark, 0}, // adjust size if xfrm output mark is present {kPadBytes, 0}, // up to NLATTR_ALIGNTO pad bytes {&encap, 0}, // adjust size if encapsulating {kPadBytes, 0}, // up to NLATTR_ALIGNTO pad bytes {&xfrm_if_id, 0}, // adjust size if interface ID is present {kPadBytes, 0}, // up to NLATTR_ALIGNTO pad bytes }; if (!record.aead.name.empty() && (!record.auth.name.empty() || !record.crypt.name.empty())) { return netdutils::statusFromErrno(EINVAL, "Invalid xfrm algo selection; AEAD is mutually " "exclusive with both Authentication and " "Encryption"); } if (record.aead.key.size() > MAX_KEY_LENGTH || record.auth.key.size() > MAX_KEY_LENGTH || record.crypt.key.size() > MAX_KEY_LENGTH) { return netdutils::statusFromErrno(EINVAL, "Key length invalid; exceeds MAX_KEY_LENGTH"); } if (record.mode != XfrmMode::TUNNEL && (record.xfrm_if_id != 0 || record.netId != 0 || record.mark.v != 0 || record.mark.m != 0)) { return netdutils::statusFromErrno(EINVAL, "xfrm_if_id, mark and netid parameters invalid " "for non tunnel-mode transform"); } else if (record.mode == XfrmMode::TUNNEL && !mIsXfrmIntfSupported && record.xfrm_if_id != 0) { return netdutils::statusFromErrno(EINVAL, "xfrm_if_id set for VTI Security Association"); } int len; len = iov[USERSA].iov_len = fillUserSaInfo(record, &usersa); iov[USERSA_PAD].iov_len = NLMSG_ALIGN(len) - len; len = iov[CRYPT].iov_len = fillNlAttrXfrmAlgoEnc(record.crypt, &crypt); iov[CRYPT_PAD].iov_len = NLA_ALIGN(len) - len; len = iov[AUTH].iov_len = fillNlAttrXfrmAlgoAuth(record.auth, &auth); iov[AUTH_PAD].iov_len = NLA_ALIGN(len) - len; len = iov[AEAD].iov_len = fillNlAttrXfrmAlgoAead(record.aead, &aead); iov[AEAD_PAD].iov_len = NLA_ALIGN(len) - len; len = iov[MARK].iov_len = fillNlAttrXfrmMark(record, &xfrmmark); iov[MARK_PAD].iov_len = NLA_ALIGN(len) - len; len = iov[OUTPUT_MARK].iov_len = fillNlAttrXfrmOutputMark(record.netId, &xfrmoutputmark); iov[OUTPUT_MARK_PAD].iov_len = NLA_ALIGN(len) - len; len = iov[ENCAP].iov_len = fillNlAttrXfrmEncapTmpl(record, &encap); iov[ENCAP_PAD].iov_len = NLA_ALIGN(len) - len; len = iov[INTF_ID].iov_len = fillNlAttrXfrmIntfId(record.xfrm_if_id, &xfrm_if_id); iov[INTF_ID_PAD].iov_len = NLA_ALIGN(len) - len; return sock.sendMessage(XFRM_MSG_UPDSA, NETLINK_REQUEST_FLAGS, 0, &iov); } int XfrmController::fillNlAttrXfrmAlgoEnc(const XfrmAlgo& inAlgo, nlattr_algo_crypt* algo) { if (inAlgo.name.empty()) { // Do not fill anything if algorithm not provided return 0; } int len = NLA_HDRLEN + sizeof(xfrm_algo); // Kernel always changes last char to null terminator; no safety checks needed. strncpy(algo->crypt.alg_name, inAlgo.name.c_str(), sizeof(algo->crypt.alg_name)); algo->crypt.alg_key_len = inAlgo.key.size() * 8; // bits memcpy(algo->key, &inAlgo.key[0], inAlgo.key.size()); len += inAlgo.key.size(); fillXfrmNlaHdr(&algo->hdr, XFRMA_ALG_CRYPT, len); return len; } int XfrmController::fillNlAttrXfrmAlgoAuth(const XfrmAlgo& inAlgo, nlattr_algo_auth* algo) { if (inAlgo.name.empty()) { // Do not fill anything if algorithm not provided return 0; } int len = NLA_HDRLEN + sizeof(xfrm_algo_auth); // Kernel always changes last char to null terminator; no safety checks needed. strncpy(algo->auth.alg_name, inAlgo.name.c_str(), sizeof(algo->auth.alg_name)); algo->auth.alg_key_len = inAlgo.key.size() * 8; // bits // This is the extra field for ALG_AUTH_TRUNC algo->auth.alg_trunc_len = inAlgo.truncLenBits; memcpy(algo->key, &inAlgo.key[0], inAlgo.key.size()); len += inAlgo.key.size(); fillXfrmNlaHdr(&algo->hdr, XFRMA_ALG_AUTH_TRUNC, len); return len; } int XfrmController::fillNlAttrXfrmAlgoAead(const XfrmAlgo& inAlgo, nlattr_algo_aead* algo) { if (inAlgo.name.empty()) { // Do not fill anything if algorithm not provided return 0; } int len = NLA_HDRLEN + sizeof(xfrm_algo_aead); // Kernel always changes last char to null terminator; no safety checks needed. strncpy(algo->aead.alg_name, inAlgo.name.c_str(), sizeof(algo->aead.alg_name)); algo->aead.alg_key_len = inAlgo.key.size() * 8; // bits // This is the extra field for ALG_AEAD. ICV length is the same as truncation length // for any AEAD algorithm. algo->aead.alg_icv_len = inAlgo.truncLenBits; memcpy(algo->key, &inAlgo.key[0], inAlgo.key.size()); len += inAlgo.key.size(); fillXfrmNlaHdr(&algo->hdr, XFRMA_ALG_AEAD, len); return len; } int XfrmController::fillNlAttrXfrmEncapTmpl(const XfrmSaInfo& record, nlattr_encap_tmpl* tmpl) { if (record.encap.type == XfrmEncapType::NONE) { return 0; } int len = NLA_HDRLEN + sizeof(xfrm_encap_tmpl); tmpl->tmpl.encap_type = static_cast(record.encap.type); tmpl->tmpl.encap_sport = htons(record.encap.srcPort); tmpl->tmpl.encap_dport = htons(record.encap.dstPort); fillXfrmNlaHdr(&tmpl->hdr, XFRMA_ENCAP, len); return len; } int XfrmController::fillUserSaInfo(const XfrmSaInfo& record, xfrm_usersa_info* usersa) { // Use AF_UNSPEC for all SAs. In transport mode, kernel picks selector family based on // usersa->family, while in tunnel mode, the XFRM_STATE_AF_UNSPEC flag allows dual-stack SAs. fillXfrmSelector(AF_UNSPEC, &usersa->sel); usersa->id.proto = IPPROTO_ESP; usersa->id.spi = record.spi; usersa->id.daddr = record.dstAddr; usersa->saddr = record.srcAddr; fillXfrmLifetimeDefaults(&usersa->lft); fillXfrmCurLifetimeDefaults(&usersa->curlft); memset(&usersa->stats, 0, sizeof(usersa->stats)); // leave stats zeroed out usersa->reqid = record.transformId; usersa->family = record.addrFamily; usersa->mode = static_cast(record.mode); usersa->replay_window = REPLAY_WINDOW_SIZE; if (record.mode == XfrmMode::TRANSPORT) { usersa->flags = 0; // TODO: should we actually set flags, XFRM_SA_XFLAG_DONT_ENCAP_DSCP? } else { usersa->flags = XFRM_STATE_AF_UNSPEC; } return sizeof(*usersa); } int XfrmController::fillUserSaId(const XfrmCommonInfo& record, xfrm_usersa_id* said) { said->daddr = record.dstAddr; said->spi = record.spi; said->family = record.addrFamily; said->proto = IPPROTO_ESP; return sizeof(*said); } netdutils::Status XfrmController::deleteSecurityAssociation(const XfrmCommonInfo& record, const XfrmSocket& sock) { xfrm_usersa_id said{}; nlattr_xfrm_mark xfrmmark{}; nlattr_xfrm_interface_id xfrm_if_id{}; enum { NLMSG_HDR, USERSAID, USERSAID_PAD, MARK, MARK_PAD, INTF_ID, INTF_ID_PAD }; std::vector iov = { {nullptr, 0}, // reserved for the eventual addition of a NLMSG_HDR {&said, 0}, // main usersa_info struct {kPadBytes, 0}, // up to NLMSG_ALIGNTO pad bytes of padding {&xfrmmark, 0}, // adjust size if xfrm mark is present {kPadBytes, 0}, // up to NLATTR_ALIGNTO pad bytes {&xfrm_if_id, 0}, // adjust size if interface ID is present {kPadBytes, 0}, // up to NLATTR_ALIGNTO pad bytes }; int len; len = iov[USERSAID].iov_len = fillUserSaId(record, &said); iov[USERSAID_PAD].iov_len = NLMSG_ALIGN(len) - len; len = iov[MARK].iov_len = fillNlAttrXfrmMark(record, &xfrmmark); iov[MARK_PAD].iov_len = NLA_ALIGN(len) - len; len = iov[INTF_ID].iov_len = fillNlAttrXfrmIntfId(record.xfrm_if_id, &xfrm_if_id); iov[INTF_ID_PAD].iov_len = NLA_ALIGN(len) - len; return sock.sendMessage(XFRM_MSG_DELSA, NETLINK_REQUEST_FLAGS, 0, &iov); } netdutils::Status XfrmController::allocateSpi(const XfrmSaInfo& record, uint32_t minSpi, uint32_t maxSpi, uint32_t* outSpi, const XfrmSocket& sock) { xfrm_userspi_info spiInfo{}; enum { NLMSG_HDR, USERSAID, USERSAID_PAD }; std::vector iov = { {nullptr, 0}, // reserved for the eventual addition of a NLMSG_HDR {&spiInfo, 0}, // main userspi_info struct {kPadBytes, 0}, // up to NLMSG_ALIGNTO pad bytes of padding }; int len; if (fillUserSaInfo(record, &spiInfo.info) == 0) { ALOGE("Failed to fill transport SA Info"); } len = iov[USERSAID].iov_len = sizeof(spiInfo); iov[USERSAID_PAD].iov_len = NLMSG_ALIGN(len) - len; RandomSpi spiGen = RandomSpi(minSpi, maxSpi); int spi; netdutils::Status ret; while ((spi = spiGen.next()) != INVALID_SPI) { spiInfo.min = spi; spiInfo.max = spi; ret = sock.sendMessage(XFRM_MSG_ALLOCSPI, NETLINK_REQUEST_FLAGS, 0, &iov); /* If the SPI is in use, we'll get ENOENT */ if (netdutils::equalToErrno(ret, ENOENT)) continue; if (isOk(ret)) { *outSpi = spi; ALOGD("Allocated an SPI: %x", *outSpi); } else { *outSpi = INVALID_SPI; ALOGE("SPI Allocation Failed with error %d", ret.code()); } return ret; } // Should always be -ENOENT if we get here return ret; } netdutils::Status XfrmController::updateTunnelModeSecurityPolicy(const XfrmSpInfo& record, const XfrmSocket& sock, XfrmDirection direction, uint16_t msgType) { xfrm_userpolicy_info userpolicy{}; nlattr_user_tmpl usertmpl{}; nlattr_xfrm_mark xfrmmark{}; nlattr_xfrm_interface_id xfrm_if_id{}; enum { NLMSG_HDR, USERPOLICY, USERPOLICY_PAD, USERTMPL, USERTMPL_PAD, MARK, MARK_PAD, INTF_ID, INTF_ID_PAD, }; std::vector iov = { {nullptr, 0}, // reserved for the eventual addition of a NLMSG_HDR {&userpolicy, 0}, // main xfrm_userpolicy_info struct {kPadBytes, 0}, // up to NLMSG_ALIGNTO pad bytes of padding {&usertmpl, 0}, // adjust size if xfrm_user_tmpl struct is present {kPadBytes, 0}, // up to NLATTR_ALIGNTO pad bytes {&xfrmmark, 0}, // adjust size if xfrm mark is present {kPadBytes, 0}, // up to NLATTR_ALIGNTO pad bytes {&xfrm_if_id, 0}, // adjust size if interface ID is present {kPadBytes, 0}, // up to NLATTR_ALIGNTO pad bytes }; int len; len = iov[USERPOLICY].iov_len = fillUserSpInfo(record, direction, &userpolicy); iov[USERPOLICY_PAD].iov_len = NLMSG_ALIGN(len) - len; len = iov[USERTMPL].iov_len = fillNlAttrUserTemplate(record, &usertmpl); iov[USERTMPL_PAD].iov_len = NLA_ALIGN(len) - len; len = iov[MARK].iov_len = fillNlAttrXfrmMark(record, &xfrmmark); iov[MARK_PAD].iov_len = NLA_ALIGN(len) - len; len = iov[INTF_ID].iov_len = fillNlAttrXfrmIntfId(record.xfrm_if_id, &xfrm_if_id); iov[INTF_ID_PAD].iov_len = NLA_ALIGN(len) - len; return sock.sendMessage(msgType, NETLINK_REQUEST_FLAGS, 0, &iov); } netdutils::Status XfrmController::deleteTunnelModeSecurityPolicy(const XfrmSpInfo& record, const XfrmSocket& sock, XfrmDirection direction) { xfrm_userpolicy_id policyid{}; nlattr_xfrm_mark xfrmmark{}; nlattr_xfrm_interface_id xfrm_if_id{}; enum { NLMSG_HDR, USERPOLICYID, USERPOLICYID_PAD, MARK, MARK_PAD, INTF_ID, INTF_ID_PAD, }; std::vector iov = { {nullptr, 0}, // reserved for the eventual addition of a NLMSG_HDR {&policyid, 0}, // main xfrm_userpolicy_id struct {kPadBytes, 0}, // up to NLMSG_ALIGNTO pad bytes of padding {&xfrmmark, 0}, // adjust size if xfrm mark is present {kPadBytes, 0}, // up to NLATTR_ALIGNTO pad bytes {&xfrm_if_id, 0}, // adjust size if interface ID is present {kPadBytes, 0}, // up to NLATTR_ALIGNTO pad bytes }; int len = iov[USERPOLICYID].iov_len = fillUserPolicyId(record, direction, &policyid); iov[USERPOLICYID_PAD].iov_len = NLMSG_ALIGN(len) - len; len = iov[MARK].iov_len = fillNlAttrXfrmMark(record, &xfrmmark); iov[MARK_PAD].iov_len = NLA_ALIGN(len) - len; len = iov[INTF_ID].iov_len = fillNlAttrXfrmIntfId(record.xfrm_if_id, &xfrm_if_id); iov[INTF_ID_PAD].iov_len = NLA_ALIGN(len) - len; return sock.sendMessage(XFRM_MSG_DELPOLICY, NETLINK_REQUEST_FLAGS, 0, &iov); } int XfrmController::fillUserSpInfo(const XfrmSpInfo& record, XfrmDirection direction, xfrm_userpolicy_info* usersp) { fillXfrmSelector(record.selAddrFamily, &usersp->sel); fillXfrmLifetimeDefaults(&usersp->lft); fillXfrmCurLifetimeDefaults(&usersp->curlft); /* if (index) index & 0x3 == dir -- must be true * xfrm_user.c:verify_newpolicy_info() */ usersp->index = 0; usersp->dir = static_cast(direction); usersp->action = XFRM_POLICY_ALLOW; usersp->flags = XFRM_POLICY_LOCALOK; usersp->share = XFRM_SHARE_UNIQUE; return sizeof(*usersp); } void XfrmController::fillUserTemplate(const XfrmSpInfo& record, xfrm_user_tmpl* tmpl) { tmpl->id.daddr = record.dstAddr; tmpl->id.spi = record.spi; tmpl->id.proto = IPPROTO_ESP; tmpl->family = record.addrFamily; tmpl->saddr = record.srcAddr; tmpl->reqid = record.transformId; tmpl->mode = static_cast(record.mode); tmpl->share = XFRM_SHARE_UNIQUE; tmpl->optional = 0; // if this is true, then a failed state lookup will be considered OK: // http://lxr.free-electrons.com/source/net/xfrm/xfrm_policy.c#L1492 tmpl->aalgos = ALGO_MASK_AUTH_ALL; // TODO: if there's a bitmask somewhere of // algos, we should find it and apply it. // I can't find one. tmpl->ealgos = ALGO_MASK_CRYPT_ALL; // TODO: if there's a bitmask somewhere... } int XfrmController::fillNlAttrUserTemplate(const XfrmSpInfo& record, nlattr_user_tmpl* tmpl) { fillUserTemplate(record, &tmpl->tmpl); int len = NLA_HDRLEN + sizeof(xfrm_user_tmpl); fillXfrmNlaHdr(&tmpl->hdr, XFRMA_TMPL, len); return len; } int XfrmController::fillNlAttrXfrmMark(const XfrmCommonInfo& record, nlattr_xfrm_mark* mark) { // Do not set if we were not given a mark if (record.mark.v == 0 && record.mark.m == 0) { return 0; } mark->mark.v = record.mark.v; // set to 0 if it's not used mark->mark.m = record.mark.m; // set to 0 if it's not used int len = NLA_HDRLEN + sizeof(xfrm_mark); fillXfrmNlaHdr(&mark->hdr, XFRMA_MARK, len); return len; } // This function sets the output mark (or set-mark in newer kernels) to that of the underlying // Network's netid. This allows outbound IPsec Tunnel mode packets to be correctly directed to a // preselected underlying Network. Packet as marked as protected from VPNs and have a network // explicitly selected to prevent interference or routing loops. Also set permission flag to // PERMISSION_SYSTEM to ensure we can use background/restricted networks. Permission to use // restricted networks is checked in IpSecService. int XfrmController::fillNlAttrXfrmOutputMark(const __u32 underlyingNetId, nlattr_xfrm_output_mark* output_mark) { // Do not set if we were not given an output mark if (underlyingNetId == 0) { return 0; } Fwmark fwmark; fwmark.netId = underlyingNetId; // TODO: Rework this to more accurately follow the underlying network fwmark.permission = PERMISSION_SYSTEM; fwmark.explicitlySelected = true; fwmark.protectedFromVpn = true; output_mark->outputMark = fwmark.intValue; int len = NLA_HDRLEN + sizeof(__u32); fillXfrmNlaHdr(&output_mark->hdr, XFRMA_OUTPUT_MARK, len); return len; } int XfrmController::fillNlAttrXfrmIntfId(const uint32_t intfIdValue, nlattr_xfrm_interface_id* intf_id) { // Do not set if we were not given an interface id if (intfIdValue == 0) { return 0; } intf_id->if_id = intfIdValue; int len = NLA_HDRLEN + sizeof(__u32); fillXfrmNlaHdr(&intf_id->hdr, XFRMA_IF_ID, len); return len; } int XfrmController::fillUserPolicyId(const XfrmSpInfo& record, XfrmDirection direction, xfrm_userpolicy_id* usersp) { // For DELPOLICY, when index is absent, selector is needed to match the policy fillXfrmSelector(record.selAddrFamily, &usersp->sel); usersp->dir = static_cast(direction); return sizeof(*usersp); } netdutils::Status XfrmController::ipSecAddTunnelInterface(const std::string& deviceName, const std::string& localAddress, const std::string& remoteAddress, int32_t ikey, int32_t okey, int32_t interfaceId, bool isUpdate) { ALOGD("XfrmController::%s, line=%d", __FUNCTION__, __LINE__); ALOGD("deviceName=%s", deviceName.c_str()); ALOGD("localAddress=%s", localAddress.c_str()); ALOGD("remoteAddress=%s", remoteAddress.c_str()); ALOGD("ikey=%0.8x", ikey); ALOGD("okey=%0.8x", okey); ALOGD("interfaceId=%0.8x", interfaceId); ALOGD("isUpdate=%d", isUpdate); uint16_t flags = isUpdate ? NETLINK_REQUEST_FLAGS : NETLINK_ROUTE_CREATE_FLAGS; if (mIsXfrmIntfSupported) { return ipSecAddXfrmInterface(deviceName, interfaceId, flags); } else { return ipSecAddVirtualTunnelInterface(deviceName, localAddress, remoteAddress, ikey, okey, flags); } } netdutils::Status XfrmController::ipSecAddXfrmInterface(const std::string& deviceName, int32_t interfaceId, uint16_t flags) { ALOGD("XfrmController::%s, line=%d", __FUNCTION__, __LINE__); if (deviceName.empty()) { return netdutils::statusFromErrno(EINVAL, "XFRM Interface deviceName empty"); } ifinfomsg ifInfoMsg{}; struct XfrmIntfCreateReq { nlattr ifNameNla; char ifName[IFNAMSIZ]; // Already aligned nlattr linkInfoNla; struct LinkInfo { nlattr infoKindNla; char infoKind[INFO_KIND_MAX_LEN]; // Already aligned nlattr infoDataNla; struct InfoData { nlattr xfrmLinkNla; uint32_t xfrmLink; nlattr xfrmIfIdNla; uint32_t xfrmIfId; } infoData; // Already aligned } linkInfo; // Already aligned } xfrmIntfCreateReq{ .ifNameNla = { .nla_len = RTA_LENGTH(IFNAMSIZ), .nla_type = IFLA_IFNAME, }, // Update .ifName via strlcpy .linkInfoNla = { .nla_len = RTA_LENGTH(sizeof(XfrmIntfCreateReq::LinkInfo)), .nla_type = IFLA_LINKINFO, }, .linkInfo = {.infoKindNla = { .nla_len = RTA_LENGTH(INFO_KIND_MAX_LEN), .nla_type = IFLA_INFO_KIND, }, // Update .infoKind via strlcpy .infoDataNla = { .nla_len = RTA_LENGTH( sizeof(XfrmIntfCreateReq::LinkInfo::InfoData)), .nla_type = IFLA_INFO_DATA, }, .infoData = { .xfrmLinkNla = { .nla_len = RTA_LENGTH(sizeof(uint32_t)), .nla_type = IFLA_XFRM_LINK, }, // Always use LOOPBACK_IFINDEX, since we use output marks for // route lookup instead. The use case of having a Network with // loopback in it is unsupported in tunnel mode. .xfrmLink = static_cast(LOOPBACK_IFINDEX), .xfrmIfIdNla = { .nla_len = RTA_LENGTH(sizeof(uint32_t)), .nla_type = IFLA_XFRM_IF_ID, }, .xfrmIfId = static_cast(interfaceId), }}}; strlcpy(xfrmIntfCreateReq.ifName, deviceName.c_str(), IFNAMSIZ); strlcpy(xfrmIntfCreateReq.linkInfo.infoKind, INFO_KIND_XFRMI, INFO_KIND_MAX_LEN); iovec iov[] = { {NULL, 0}, // reserved for the eventual addition of a NLMSG_HDR {&ifInfoMsg, sizeof(ifInfoMsg)}, {&xfrmIntfCreateReq, sizeof(xfrmIntfCreateReq)}, }; // sendNetlinkRequest returns -errno int ret = -sendNetlinkRequest(RTM_NEWLINK, flags, iov, ARRAY_SIZE(iov), nullptr); return netdutils::statusFromErrno(ret, "Add/update xfrm interface"); } netdutils::Status XfrmController::ipSecAddVirtualTunnelInterface(const std::string& deviceName, const std::string& localAddress, const std::string& remoteAddress, int32_t ikey, int32_t okey, uint16_t flags) { ALOGD("XfrmController::%s, line=%d", __FUNCTION__, __LINE__); if (deviceName.empty() || localAddress.empty() || remoteAddress.empty()) { return netdutils::statusFromErrno(EINVAL, "Required VTI creation parameter not provided"); } uint8_t PADDING_BUFFER[] = {0, 0, 0, 0}; // Find address family. uint8_t remAddr[sizeof(in6_addr)]; StatusOr statusOrRemoteFam = convertStringAddress(remoteAddress, remAddr); RETURN_IF_NOT_OK(statusOrRemoteFam); uint8_t locAddr[sizeof(in6_addr)]; StatusOr statusOrLocalFam = convertStringAddress(localAddress, locAddr); RETURN_IF_NOT_OK(statusOrLocalFam); if (statusOrLocalFam.value() != statusOrRemoteFam.value()) { return netdutils::statusFromErrno(EINVAL, "Local and remote address families do not match"); } uint16_t family = statusOrLocalFam.value(); ifinfomsg ifInfoMsg{}; // Construct IFLA_IFNAME nlattr iflaIfName; char iflaIfNameStrValue[deviceName.length() + 1]; size_t iflaIfNameLength = strlcpy(iflaIfNameStrValue, deviceName.c_str(), sizeof(iflaIfNameStrValue)); size_t iflaIfNamePad = fillNlAttr(IFLA_IFNAME, iflaIfNameLength, &iflaIfName); // Construct IFLA_INFO_KIND // Constants "vti6" and "vti" enable the kernel to call different code paths, // (ip_tunnel.c, ip6_tunnel), based on the family. const std::string infoKindValue = (family == AF_INET6) ? INFO_KIND_VTI6 : INFO_KIND_VTI; nlattr iflaIfInfoKind; char infoKindValueStrValue[infoKindValue.length() + 1]; size_t iflaIfInfoKindLength = strlcpy(infoKindValueStrValue, infoKindValue.c_str(), sizeof(infoKindValueStrValue)); size_t iflaIfInfoKindPad = fillNlAttr(IFLA_INFO_KIND, iflaIfInfoKindLength, &iflaIfInfoKind); // Construct IFLA_VTI_LOCAL nlattr iflaVtiLocal; uint8_t binaryLocalAddress[sizeof(in6_addr)]; size_t iflaVtiLocalPad = fillNlAttrIpAddress(IFLA_VTI_LOCAL, family, localAddress, &iflaVtiLocal, netdutils::makeSlice(binaryLocalAddress)); // Construct IFLA_VTI_REMOTE nlattr iflaVtiRemote; uint8_t binaryRemoteAddress[sizeof(in6_addr)]; size_t iflaVtiRemotePad = fillNlAttrIpAddress(IFLA_VTI_REMOTE, family, remoteAddress, &iflaVtiRemote, netdutils::makeSlice(binaryRemoteAddress)); // Construct IFLA_VTI_OKEY nlattr_payload_u32 iflaVtiIKey; size_t iflaVtiIKeyPad = fillNlAttrU32(IFLA_VTI_IKEY, htonl(ikey), &iflaVtiIKey); // Construct IFLA_VTI_IKEY nlattr_payload_u32 iflaVtiOKey; size_t iflaVtiOKeyPad = fillNlAttrU32(IFLA_VTI_OKEY, htonl(okey), &iflaVtiOKey); int iflaInfoDataPayloadLength = iflaVtiLocal.nla_len + iflaVtiLocalPad + iflaVtiRemote.nla_len + iflaVtiRemotePad + iflaVtiIKey.hdr.nla_len + iflaVtiIKeyPad + iflaVtiOKey.hdr.nla_len + iflaVtiOKeyPad; // Construct IFLA_INFO_DATA nlattr iflaInfoData; size_t iflaInfoDataPad = fillNlAttr(IFLA_INFO_DATA, iflaInfoDataPayloadLength, &iflaInfoData); // Construct IFLA_LINKINFO nlattr iflaLinkInfo; size_t iflaLinkInfoPad = fillNlAttr(IFLA_LINKINFO, iflaInfoData.nla_len + iflaInfoDataPad + iflaIfInfoKind.nla_len + iflaIfInfoKindPad, &iflaLinkInfo); iovec iov[] = { {nullptr, 0}, {&ifInfoMsg, sizeof(ifInfoMsg)}, {&iflaIfName, sizeof(iflaIfName)}, {iflaIfNameStrValue, iflaIfNameLength}, {&PADDING_BUFFER, iflaIfNamePad}, {&iflaLinkInfo, sizeof(iflaLinkInfo)}, {&iflaIfInfoKind, sizeof(iflaIfInfoKind)}, {infoKindValueStrValue, iflaIfInfoKindLength}, {&PADDING_BUFFER, iflaIfInfoKindPad}, {&iflaInfoData, sizeof(iflaInfoData)}, {&iflaVtiLocal, sizeof(iflaVtiLocal)}, {&binaryLocalAddress, (family == AF_INET) ? sizeof(in_addr) : sizeof(in6_addr)}, {&PADDING_BUFFER, iflaVtiLocalPad}, {&iflaVtiRemote, sizeof(iflaVtiRemote)}, {&binaryRemoteAddress, (family == AF_INET) ? sizeof(in_addr) : sizeof(in6_addr)}, {&PADDING_BUFFER, iflaVtiRemotePad}, {&iflaVtiIKey, iflaVtiIKey.hdr.nla_len}, {&PADDING_BUFFER, iflaVtiIKeyPad}, {&iflaVtiOKey, iflaVtiOKey.hdr.nla_len}, {&PADDING_BUFFER, iflaVtiOKeyPad}, {&PADDING_BUFFER, iflaInfoDataPad}, {&PADDING_BUFFER, iflaLinkInfoPad}, }; // sendNetlinkRequest returns -errno int ret = -1 * sendNetlinkRequest(RTM_NEWLINK, flags, iov, ARRAY_SIZE(iov), nullptr); return netdutils::statusFromErrno(ret, "Failed to add/update virtual tunnel interface"); } netdutils::Status XfrmController::ipSecRemoveTunnelInterface(const std::string& deviceName) { ALOGD("XfrmController::%s, line=%d", __FUNCTION__, __LINE__); ALOGD("deviceName=%s", deviceName.c_str()); if (deviceName.empty()) { return netdutils::statusFromErrno(EINVAL, "Required parameter not provided"); } uint8_t PADDING_BUFFER[] = {0, 0, 0, 0}; ifinfomsg ifInfoMsg{}; nlattr iflaIfName; char iflaIfNameStrValue[deviceName.length() + 1]; size_t iflaIfNameLength = strlcpy(iflaIfNameStrValue, deviceName.c_str(), sizeof(iflaIfNameStrValue)); size_t iflaIfNamePad = fillNlAttr(IFLA_IFNAME, iflaIfNameLength, &iflaIfName); iovec iov[] = { {nullptr, 0}, {&ifInfoMsg, sizeof(ifInfoMsg)}, {&iflaIfName, sizeof(iflaIfName)}, {iflaIfNameStrValue, iflaIfNameLength}, {&PADDING_BUFFER, iflaIfNamePad}, }; uint16_t action = RTM_DELLINK; uint16_t flags = NLM_F_REQUEST | NLM_F_ACK; // sendNetlinkRequest returns -errno int ret = -1 * sendNetlinkRequest(action, flags, iov, ARRAY_SIZE(iov), nullptr); return netdutils::statusFromErrno(ret, "Error in deleting IpSec interface " + deviceName); } void XfrmController::dump(DumpWriter& dw) { ScopedIndent indentForXfrmController(dw); dw.println("XfrmController"); ScopedIndent indentForXfrmISupport(dw); dw.println("XFRM-I support: %d", mIsXfrmIntfSupported); } } // namespace net } // namespace android