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Diffstat (limited to 'test/util/proc_util.cc')
-rw-r--r-- | test/util/proc_util.cc | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/test/util/proc_util.cc b/test/util/proc_util.cc new file mode 100644 index 000000000..34d636ba9 --- /dev/null +++ b/test/util/proc_util.cc @@ -0,0 +1,107 @@ +// 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 |