// Copyright 2018 The gVisor Authors. // // 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 "test/util/proc_util.h" #include <algorithm> #include <iostream> #include <vector> #include "absl/strings/ascii.h" #include "absl/strings/str_cat.h" #include "absl/strings/str_split.h" #include "absl/strings/string_view.h" #include "test/util/fs_util.h" #include "test/util/test_util.h" namespace gvisor { namespace testing { // Parses a single line from /proc/<xxx>/maps. PosixErrorOr<ProcMapsEntry> ParseProcMapsLine(absl::string_view line) { ProcMapsEntry map_entry = {}; // Limit splitting to 6 parts so that if there is a file path and it contains // spaces, the file path is not split. std::vector<std::string> parts = absl::StrSplit(line, absl::MaxSplits(' ', 5), absl::SkipEmpty()); // parts.size() should be 6 if there is a file name specified, and 5 // otherwise. if (parts.size() < 5) { return PosixError(EINVAL, absl::StrCat("Invalid line: ", line)); } // Address range in the form X-X where X are hex values without leading 0x. std::vector<std::string> addresses = absl::StrSplit(parts[0], '-'); if (addresses.size() != 2) { return PosixError(EINVAL, absl::StrCat("Invalid address range: ", parts[0])); } ASSIGN_OR_RETURN_ERRNO(map_entry.start, AtoiBase(addresses[0], 16)); ASSIGN_OR_RETURN_ERRNO(map_entry.end, AtoiBase(addresses[1], 16)); // Permissions are four bytes of the form rwxp or - if permission not set. if (parts[1].size() != 4) { return PosixError(EINVAL, absl::StrCat("Invalid permission field: ", parts[1])); } map_entry.readable = parts[1][0] == 'r'; map_entry.writable = parts[1][1] == 'w'; map_entry.executable = parts[1][2] == 'x'; map_entry.priv = parts[1][3] == 'p'; ASSIGN_OR_RETURN_ERRNO(map_entry.offset, AtoiBase(parts[2], 16)); std::vector<std::string> device = absl::StrSplit(parts[3], ':'); if (device.size() != 2) { return PosixError(EINVAL, absl::StrCat("Invalid device: ", parts[3])); } ASSIGN_OR_RETURN_ERRNO(map_entry.major, AtoiBase(device[0], 16)); ASSIGN_OR_RETURN_ERRNO(map_entry.minor, AtoiBase(device[1], 16)); ASSIGN_OR_RETURN_ERRNO(map_entry.inode, Atoi<int64_t>(parts[4])); if (parts.size() == 6) { // A filename is present. However, absl::StrSplit retained the whitespace // between the inode number and the filename. map_entry.filename = std::string(absl::StripLeadingAsciiWhitespace(parts[5])); } return map_entry; } PosixErrorOr<std::vector<ProcMapsEntry>> ParseProcMaps( absl::string_view contents) { std::vector<ProcMapsEntry> entries; auto lines = absl::StrSplit(contents, '\n', absl::SkipEmpty()); for (const auto& l : lines) { std::cout << "line: " << l << std::endl; ASSIGN_OR_RETURN_ERRNO(auto entry, ParseProcMapsLine(l)); entries.push_back(entry); } return entries; } PosixErrorOr<bool> IsVsyscallEnabled() { ASSIGN_OR_RETURN_ERRNO(auto contents, GetContents("/proc/self/maps")); ASSIGN_OR_RETURN_ERRNO(auto maps, ParseProcMaps(contents)); return std::any_of(maps.begin(), maps.end(), [](const ProcMapsEntry& e) { return e.filename == "[vsyscall]"; }); } } // namespace testing } // namespace gvisor