trusty/coverage/coverage.cpp - android_system_core - Gitiles

 /*
  * Copyright (C) 2020 The Android Open Sourete 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.
  */

 #define LOG_TAG "coverage"

 #include <BufferAllocator/BufferAllocator.h>
 #include <android-base/file.h>
 #include <android-base/logging.h>
 #include <android-base/unique_fd.h>
 #include <assert.h>
 #include <log/log.h>
 #include <stdio.h>
 #include <sys/mman.h>
 #include <sys/uio.h>
 #include <trusty/coverage/coverage.h>
 #include <trusty/coverage/record.h>
 #include <trusty/coverage/tipc.h>
 #include <trusty/tipc.h>
 #include <iostream>

 #define COVERAGE_CLIENT_PORT "com.android.trusty.coverage.client"

 namespace android {
 namespace trusty {
 namespace coverage {

 using android::base::ErrnoError;
 using android::base::Error;
 using std::string;
 using std::to_string;
 using std::unique_ptr;

 static inline uintptr_t RoundPageUp(uintptr_t val) {
     return (val + (PAGE_SIZE - 1)) & ~(PAGE_SIZE - 1);
 }

 CoverageRecord::CoverageRecord(string tipc_dev, struct uuid* uuid)
     : tipc_dev_(std::move(tipc_dev)),
       coverage_srv_fd_(-1),
       uuid_(*uuid),
       sancov_filename_(),
       record_len_(0),
       shm_(NULL),
       shm_len_(0) {}

 CoverageRecord::CoverageRecord(string tipc_dev, struct uuid* uuid, string module_name)
     : tipc_dev_(std::move(tipc_dev)),
       coverage_srv_fd_(-1),
       uuid_(*uuid),
       sancov_filename_(module_name + "." + to_string(getpid()) + ".sancov"),
       record_len_(0),
       shm_(NULL),
       shm_len_(0) {}

 CoverageRecord::~CoverageRecord() {
     if (shm_) {
         if (sancov_filename_) {
             auto res = SaveSancovFile(*sancov_filename_);
             if (!res.ok()) {
                 ALOGE("Could not write sancov file for module: %s\n", sancov_filename_->c_str());
             }
         }

         munmap((void*)shm_, shm_len_);
     }
 }

 Result<void> CoverageRecord::Rpc(coverage_client_req* req, int req_fd, coverage_client_resp* resp) {
     int rc;

     if (req_fd < 0) {
         rc = write(coverage_srv_fd_, req, sizeof(*req));
     } else {
         iovec iov = {
                 .iov_base = req,
                 .iov_len = sizeof(*req),
         };

         trusty_shm shm = {
                 .fd = req_fd,
                 .transfer = TRUSTY_SHARE,
         };

         rc = tipc_send(coverage_srv_fd_, &iov, 1, &shm, 1);
     }

     if (rc != (int)sizeof(*req)) {
         return ErrnoError() << "failed to send request to coverage server: ";
     }

     rc = read(coverage_srv_fd_, resp, sizeof(*resp));
     if (rc != (int)sizeof(*resp)) {
         return ErrnoError() << "failed to read reply from coverage server: ";
     }

     if (resp->hdr.cmd != (req->hdr.cmd | COVERAGE_CLIENT_CMD_RESP_BIT)) {
         return ErrnoError() << "unknown response cmd: " << resp->hdr.cmd;
     }

     return {};
 }

 Result<void> CoverageRecord::Open() {
     coverage_client_req req;
     coverage_client_resp resp;

     if (shm_) {
         return {}; /* already initialized */
     }

     int fd = tipc_connect(tipc_dev_.c_str(), COVERAGE_CLIENT_PORT);
     if (fd < 0) {
         // Don't error out to support fuzzing builds without coverage, e.g. for repros.
         std::cerr << "WARNING!!! Failed to connect to Trusty coverarge server." << std::endl;
         return {};
     }
     coverage_srv_fd_.reset(fd);

     req.hdr.cmd = COVERAGE_CLIENT_CMD_OPEN;
     req.open_args.uuid = uuid_;
     auto ret = Rpc(&req, -1, &resp);
     if (!ret.ok()) {
         return Error() << "failed to open coverage client: " << ret.error();
     }
     record_len_ = resp.open_args.record_len;
     shm_len_ = RoundPageUp(record_len_);

     BufferAllocator allocator;

     fd = allocator.Alloc("system", shm_len_);
     if (fd < 0) {
         return ErrnoError() << "failed to create dmabuf of size " << shm_len_
                             << " err code: " << fd;
     }
     unique_fd dma_buf(fd);

     void* shm = mmap(0, shm_len_, PROT_READ | PROT_WRITE, MAP_SHARED, dma_buf, 0);
     if (shm == MAP_FAILED) {
         return ErrnoError() << "failed to map memfd: ";
     }

     req.hdr.cmd = COVERAGE_CLIENT_CMD_SHARE_RECORD;
     req.share_record_args.shm_len = shm_len_;
     ret = Rpc(&req, dma_buf, &resp);
     if (!ret.ok()) {
         return Error() << "failed to send shared memory: " << ret.error();
     }

     shm_ = shm;
     return {};
 }

 bool CoverageRecord::IsOpen() {
     return shm_;
 }

 void CoverageRecord::ResetFullRecord() {
     auto header_region = GetRegionBounds(COV_START);
     if (!header_region.ok()) {
         // If the header cannot be parsed, we can't reset the proper region yet.
         return;
     }

     for (size_t i = header_region->second; i < shm_len_; i++) {
         *((volatile uint8_t*)shm_ + i) = 0;
     }
 }

 void CoverageRecord::ResetCounts() {
     volatile uint8_t* begin = nullptr;
     volatile uint8_t* end = nullptr;
     GetRawCounts(&begin, &end);

     for (volatile uint8_t* x = begin; x < end; x++) {
         *x = 0;
     }
 }

 void CoverageRecord::ResetPCs() {
     volatile uintptr_t* begin = nullptr;
     volatile uintptr_t* end = nullptr;
     GetRawPCs(&begin, &end);

     for (volatile uintptr_t* x = begin; x < end; x++) {
         *x = 0;
     }
 }

 Result<std::pair<size_t, size_t>> CoverageRecord::GetRegionBounds(uint32_t region_type) {
     assert(shm_);

     auto header = (volatile struct coverage_record_header*)shm_;

     if (header->type != COV_START) {
         return Error() << "Header not yet valid";
     }

     for (++header; header->type != COV_TOTAL_LENGTH; ++header) {
         if (header->type == region_type) {
             // Coverage record must end with a COV_TOTAL_LENGTH header entry, so
             // it is always safe to read the next entry since we don't iterate
             // over the COV_TOTAL_LENGTH entry.
             return {{header->offset, (header + 1)->offset}};
         }
     }

     return Error() << "Could not find coverage region type: " << region_type;
 }

 void CoverageRecord::GetRawData(volatile void** begin, volatile void** end) {
     assert(shm_);

     *begin = shm_;
     *end = (uint8_t*)(*begin) + record_len_;
 }

 void CoverageRecord::GetRawCounts(volatile uint8_t** begin, volatile uint8_t** end) {
     auto region = GetRegionBounds(COV_8BIT_COUNTERS);
     if (!region.ok()) {
         *begin = 0;
         *end = 0;
         return;
     }

     assert(region->second <= record_len_);

     *begin = (volatile uint8_t*)shm_ + region->first;
     *end = (volatile uint8_t*)shm_ + region->second;
 }

 void CoverageRecord::GetRawPCs(volatile uintptr_t** begin, volatile uintptr_t** end) {
     auto region = GetRegionBounds(COV_INSTR_PCS);
     if (!region.ok()) {
         *begin = 0;
         *end = 0;
         return;
     }

     assert(region->second <= record_len_);

     *begin = (volatile uintptr_t*)((volatile uint8_t*)shm_ + region->first);
     *end = (volatile uintptr_t*)((volatile uint8_t*)shm_ + region->second);
 }

 uint64_t CoverageRecord::TotalEdgeCounts() {
     assert(shm_);

     uint64_t counter = 0;

     volatile uint8_t* begin = NULL;
     volatile uint8_t* end = NULL;

     GetRawCounts(&begin, &end);

     for (volatile uint8_t* x = begin; x < end; x++) {
         counter += *x;
     }

     return counter;
 }

 Result<void> CoverageRecord::SaveSancovFile(const std::string& filename) {
     android::base::unique_fd output_fd(TEMP_FAILURE_RETRY(creat(filename.c_str(), 00644)));
     if (!output_fd.ok()) {
         return ErrnoError() << "Could not open sancov file";
     }

     uint64_t magic;
     if (sizeof(uintptr_t) == 8) {
         magic = 0xC0BFFFFFFFFFFF64;
     } else if (sizeof(uintptr_t) == 4) {
         magic = 0xC0BFFFFFFFFFFF32;
     }
     WriteFully(output_fd, &magic, sizeof(magic));

     volatile uintptr_t* begin = nullptr;
     volatile uintptr_t* end = nullptr;

     GetRawPCs(&begin, &end);

     for (volatile uintptr_t* pc_ptr = begin; pc_ptr < end; pc_ptr++) {
         uintptr_t pc = *pc_ptr;
         if (pc) {
             WriteFully(output_fd, &pc, sizeof(pc));
         }
     }

     return {};
 }

 }  // namespace coverage
 }  // namespace trusty
 }  // namespace android
	/*
	* Copyright (C) 2020 The Android Open Sourete 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.
	*/

	#define LOG_TAG "coverage"

	#include <BufferAllocator/BufferAllocator.h>
	#include <android-base/file.h>
	#include <android-base/logging.h>
	#include <android-base/unique_fd.h>
	#include <assert.h>
	#include <log/log.h>
	#include <stdio.h>
	#include <sys/mman.h>
	#include <sys/uio.h>
	#include <trusty/coverage/coverage.h>
	#include <trusty/coverage/record.h>
	#include <trusty/coverage/tipc.h>
	#include <trusty/tipc.h>
	#include <iostream>

	#define COVERAGE_CLIENT_PORT "com.android.trusty.coverage.client"

	namespace android {
	namespace trusty {
	namespace coverage {

	using android::base::ErrnoError;
	using android::base::Error;
	using std::string;
	using std::to_string;
	using std::unique_ptr;

	static inline uintptr_t RoundPageUp(uintptr_t val) {
	return (val + (PAGE_SIZE - 1)) & ~(PAGE_SIZE - 1);
	}

	CoverageRecord::CoverageRecord(string tipc_dev, struct uuid* uuid)
	: tipc_dev_(std::move(tipc_dev)),
	coverage_srv_fd_(-1),
	uuid_(*uuid),
	sancov_filename_(),
	record_len_(0),
	shm_(NULL),
	shm_len_(0) {}

	CoverageRecord::CoverageRecord(string tipc_dev, struct uuid* uuid, string module_name)
	: tipc_dev_(std::move(tipc_dev)),
	coverage_srv_fd_(-1),
	uuid_(*uuid),
	sancov_filename_(module_name + "." + to_string(getpid()) + ".sancov"),
	record_len_(0),
	shm_(NULL),
	shm_len_(0) {}

	CoverageRecord::~CoverageRecord() {
	if (shm_) {
	if (sancov_filename_) {
	auto res = SaveSancovFile(*sancov_filename_);
	if (!res.ok()) {
	ALOGE("Could not write sancov file for module: %s\n", sancov_filename_->c_str());
	}
	}

	munmap((void*)shm_, shm_len_);
	}
	}

	Result<void> CoverageRecord::Rpc(coverage_client_req* req, int req_fd, coverage_client_resp* resp) {
	int rc;

	if (req_fd < 0) {
	rc = write(coverage_srv_fd_, req, sizeof(*req));
	} else {
	iovec iov = {
	.iov_base = req,
	.iov_len = sizeof(*req),
	};

	trusty_shm shm = {
	.fd = req_fd,
	.transfer = TRUSTY_SHARE,
	};

	rc = tipc_send(coverage_srv_fd_, &iov, 1, &shm, 1);
	}

	if (rc != (int)sizeof(*req)) {
	return ErrnoError() << "failed to send request to coverage server: ";
	}

	rc = read(coverage_srv_fd_, resp, sizeof(*resp));
	if (rc != (int)sizeof(*resp)) {
	return ErrnoError() << "failed to read reply from coverage server: ";
	}

	if (resp->hdr.cmd != (req->hdr.cmd \| COVERAGE_CLIENT_CMD_RESP_BIT)) {
	return ErrnoError() << "unknown response cmd: " << resp->hdr.cmd;
	}

	return {};
	}

	Result<void> CoverageRecord::Open() {
	coverage_client_req req;
	coverage_client_resp resp;

	if (shm_) {
	return {}; /* already initialized */
	}

	int fd = tipc_connect(tipc_dev_.c_str(), COVERAGE_CLIENT_PORT);
	if (fd < 0) {
	// Don't error out to support fuzzing builds without coverage, e.g. for repros.
	std::cerr << "WARNING!!! Failed to connect to Trusty coverarge server." << std::endl;
	return {};
	}
	coverage_srv_fd_.reset(fd);

	req.hdr.cmd = COVERAGE_CLIENT_CMD_OPEN;
	req.open_args.uuid = uuid_;
	auto ret = Rpc(&req, -1, &resp);
	if (!ret.ok()) {
	return Error() << "failed to open coverage client: " << ret.error();
	}
	record_len_ = resp.open_args.record_len;
	shm_len_ = RoundPageUp(record_len_);

	BufferAllocator allocator;

	fd = allocator.Alloc("system", shm_len_);
	if (fd < 0) {
	return ErrnoError() << "failed to create dmabuf of size " << shm_len_
	<< " err code: " << fd;
	}
	unique_fd dma_buf(fd);

	void* shm = mmap(0, shm_len_, PROT_READ \| PROT_WRITE, MAP_SHARED, dma_buf, 0);
	if (shm == MAP_FAILED) {
	return ErrnoError() << "failed to map memfd: ";
	}

	req.hdr.cmd = COVERAGE_CLIENT_CMD_SHARE_RECORD;
	req.share_record_args.shm_len = shm_len_;
	ret = Rpc(&req, dma_buf, &resp);
	if (!ret.ok()) {
	return Error() << "failed to send shared memory: " << ret.error();
	}

	shm_ = shm;
	return {};
	}

	bool CoverageRecord::IsOpen() {
	return shm_;
	}

	void CoverageRecord::ResetFullRecord() {
	auto header_region = GetRegionBounds(COV_START);
	if (!header_region.ok()) {
	// If the header cannot be parsed, we can't reset the proper region yet.
	return;
	}

	for (size_t i = header_region->second; i < shm_len_; i++) {
	((volatile uint8_t)shm_ + i) = 0;
	}
	}

	void CoverageRecord::ResetCounts() {
	volatile uint8_t* begin = nullptr;
	volatile uint8_t* end = nullptr;
	GetRawCounts(&begin, &end);

	for (volatile uint8_t* x = begin; x < end; x++) {
	*x = 0;
	}
	}

	void CoverageRecord::ResetPCs() {
	volatile uintptr_t* begin = nullptr;
	volatile uintptr_t* end = nullptr;
	GetRawPCs(&begin, &end);

	for (volatile uintptr_t* x = begin; x < end; x++) {
	*x = 0;
	}
	}

	Result<std::pair<size_t, size_t>> CoverageRecord::GetRegionBounds(uint32_t region_type) {
	assert(shm_);

	auto header = (volatile struct coverage_record_header*)shm_;

	if (header->type != COV_START) {
	return Error() << "Header not yet valid";
	}

	for (++header; header->type != COV_TOTAL_LENGTH; ++header) {
	if (header->type == region_type) {
	// Coverage record must end with a COV_TOTAL_LENGTH header entry, so
	// it is always safe to read the next entry since we don't iterate
	// over the COV_TOTAL_LENGTH entry.
	return {{header->offset, (header + 1)->offset}};
	}
	}

	return Error() << "Could not find coverage region type: " << region_type;
	}

	void CoverageRecord::GetRawData(volatile void begin, volatile void end) {
	assert(shm_);

	*begin = shm_;
	end = (uint8_t)(*begin) + record_len_;
	}

	void CoverageRecord::GetRawCounts(volatile uint8_t begin, volatile uint8_t end) {
	auto region = GetRegionBounds(COV_8BIT_COUNTERS);
	if (!region.ok()) {
	*begin = 0;
	*end = 0;
	return;
	}

	assert(region->second <= record_len_);

	begin = (volatile uint8_t)shm_ + region->first;
	end = (volatile uint8_t)shm_ + region->second;
	}

	void CoverageRecord::GetRawPCs(volatile uintptr_t begin, volatile uintptr_t end) {
	auto region = GetRegionBounds(COV_INSTR_PCS);
	if (!region.ok()) {
	*begin = 0;
	*end = 0;
	return;
	}

	assert(region->second <= record_len_);

	begin = (volatile uintptr_t)((volatile uint8_t*)shm_ + region->first);
	end = (volatile uintptr_t)((volatile uint8_t*)shm_ + region->second);
	}

	uint64_t CoverageRecord::TotalEdgeCounts() {
	assert(shm_);

	uint64_t counter = 0;

	volatile uint8_t* begin = NULL;
	volatile uint8_t* end = NULL;

	GetRawCounts(&begin, &end);

	for (volatile uint8_t* x = begin; x < end; x++) {
	counter += *x;
	}

	return counter;
	}

	Result<void> CoverageRecord::SaveSancovFile(const std::string& filename) {
	android::base::unique_fd output_fd(TEMP_FAILURE_RETRY(creat(filename.c_str(), 00644)));
	if (!output_fd.ok()) {
	return ErrnoError() << "Could not open sancov file";
	}

	uint64_t magic;
	if (sizeof(uintptr_t) == 8) {
	magic = 0xC0BFFFFFFFFFFF64;
	} else if (sizeof(uintptr_t) == 4) {
	magic = 0xC0BFFFFFFFFFFF32;
	}
	WriteFully(output_fd, &magic, sizeof(magic));

	volatile uintptr_t* begin = nullptr;
	volatile uintptr_t* end = nullptr;

	GetRawPCs(&begin, &end);

	for (volatile uintptr_t* pc_ptr = begin; pc_ptr < end; pc_ptr++) {
	uintptr_t pc = *pc_ptr;
	if (pc) {
	WriteFully(output_fd, &pc, sizeof(pc));
	}
	}

	return {};
	}

	} // namespace coverage
	} // namespace trusty
	} // namespace android