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author | iddqd <iddqd@yandex-team.com> | 2024-12-19 10:46:06 +0300 |
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committer | iddqd <iddqd@yandex-team.com> | 2024-12-19 10:59:56 +0300 |
commit | bb0840c0025a75dd3b85b746ebcec7deb7d9fe1c (patch) | |
tree | 85bc5522e873d9d5c37df278f0300c26fe9e729e /contrib/libs/breakpad/src/common/linux/file_id.cc | |
parent | 1353077f79bb3547792b2fc86c22a695f0bc76f9 (diff) | |
download | ydb-bb0840c0025a75dd3b85b746ebcec7deb7d9fe1c.tar.gz |
Add contib/libs/breakpad to export
commit_hash:9d85255f8d9249f14105e4626bf4484805b8aed4
Diffstat (limited to 'contrib/libs/breakpad/src/common/linux/file_id.cc')
-rw-r--r-- | contrib/libs/breakpad/src/common/linux/file_id.cc | 203 |
1 files changed, 203 insertions, 0 deletions
diff --git a/contrib/libs/breakpad/src/common/linux/file_id.cc b/contrib/libs/breakpad/src/common/linux/file_id.cc new file mode 100644 index 0000000000..b483eb5c02 --- /dev/null +++ b/contrib/libs/breakpad/src/common/linux/file_id.cc @@ -0,0 +1,203 @@ +// Copyright (c) 2006, Google Inc. +// All rights reserved. +// +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following disclaimer +// in the documentation and/or other materials provided with the +// distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived from +// this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +// +// file_id.cc: Return a unique identifier for a file +// +// See file_id.h for documentation +// + +#include "common/linux/file_id.h" + +#include <arpa/inet.h> +#include <assert.h> +#include <string.h> + +#include <algorithm> +#include <string> + +#include "common/linux/elf_gnu_compat.h" +#include "common/linux/elfutils.h" +#include "common/linux/linux_libc_support.h" +#include "common/linux/memory_mapped_file.h" +#include "common/using_std_string.h" +#include "third_party/lss/linux_syscall_support.h" + +namespace google_breakpad { +namespace elf { + +// Used in a few places for backwards-compatibility. +const size_t kMDGUIDSize = sizeof(MDGUID); + +FileID::FileID(const char* path) : path_(path) {} + +// ELF note name and desc are 32-bits word padded. +#define NOTE_PADDING(a) ((a + 3) & ~3) + +// These functions are also used inside the crashed process, so be safe +// and use the syscall/libc wrappers instead of direct syscalls or libc. + +static bool ElfClassBuildIDNoteIdentifier(const void* section, size_t length, + wasteful_vector<uint8_t>& identifier) { + static_assert(sizeof(ElfClass32::Nhdr) == sizeof(ElfClass64::Nhdr), + "Elf32_Nhdr and Elf64_Nhdr should be the same"); + typedef typename ElfClass32::Nhdr Nhdr; + + const void* section_end = reinterpret_cast<const char*>(section) + length; + const Nhdr* note_header = reinterpret_cast<const Nhdr*>(section); + while (reinterpret_cast<const void*>(note_header) < section_end) { + if (note_header->n_type == NT_GNU_BUILD_ID) + break; + note_header = reinterpret_cast<const Nhdr*>( + reinterpret_cast<const char*>(note_header) + sizeof(Nhdr) + + NOTE_PADDING(note_header->n_namesz) + + NOTE_PADDING(note_header->n_descsz)); + } + if (reinterpret_cast<const void*>(note_header) >= section_end || + note_header->n_descsz == 0) { + return false; + } + + const uint8_t* build_id = reinterpret_cast<const uint8_t*>(note_header) + + sizeof(Nhdr) + NOTE_PADDING(note_header->n_namesz); + identifier.insert(identifier.end(), + build_id, + build_id + note_header->n_descsz); + + return true; +} + +// Attempt to locate a .note.gnu.build-id section in an ELF binary +// and copy it into |identifier|. +static bool FindElfBuildIDNote(const void* elf_mapped_base, + wasteful_vector<uint8_t>& identifier) { + PageAllocator allocator; + // lld normally creates 2 PT_NOTEs, gold normally creates 1. + auto_wasteful_vector<ElfSegment, 2> segs(&allocator); + if (FindElfSegments(elf_mapped_base, PT_NOTE, &segs)) { + for (ElfSegment& seg : segs) { + if (ElfClassBuildIDNoteIdentifier(seg.start, seg.size, identifier)) { + return true; + } + } + } + + void* note_section; + size_t note_size; + if (FindElfSection(elf_mapped_base, ".note.gnu.build-id", SHT_NOTE, + (const void**)¬e_section, ¬e_size)) { + return ElfClassBuildIDNoteIdentifier(note_section, note_size, identifier); + } + + return false; +} + +// Attempt to locate the .text section of an ELF binary and generate +// a simple hash by XORing the first page worth of bytes into |identifier|. +static bool HashElfTextSection(const void* elf_mapped_base, + wasteful_vector<uint8_t>& identifier) { + identifier.resize(kMDGUIDSize); + + void* text_section; + size_t text_size; + if (!FindElfSection(elf_mapped_base, ".text", SHT_PROGBITS, + (const void**)&text_section, &text_size) || + text_size == 0) { + return false; + } + + // Only provide |kMDGUIDSize| bytes to keep identifiers produced by this + // function backwards-compatible. + my_memset(&identifier[0], 0, kMDGUIDSize); + const uint8_t* ptr = reinterpret_cast<const uint8_t*>(text_section); + const uint8_t* ptr_end = ptr + std::min(text_size, static_cast<size_t>(4096)); + while (ptr < ptr_end) { + for (unsigned i = 0; i < kMDGUIDSize; i++) + identifier[i] ^= ptr[i]; + ptr += kMDGUIDSize; + } + return true; +} + +// static +bool FileID::ElfFileIdentifierFromMappedFile(const void* base, + wasteful_vector<uint8_t>& identifier) { + // Look for a build id note first. + if (FindElfBuildIDNote(base, identifier)) + return true; + + // Fall back on hashing the first page of the text section. + return HashElfTextSection(base, identifier); +} + +bool FileID::ElfFileIdentifier(wasteful_vector<uint8_t>& identifier) { + MemoryMappedFile mapped_file(path_.c_str(), 0); + if (!mapped_file.data()) // Should probably check if size >= ElfW(Ehdr)? + return false; + + return ElfFileIdentifierFromMappedFile(mapped_file.data(), identifier); +} + +// These three functions are not ever called in an unsafe context, so it's OK +// to allocate memory and use libc. +static string bytes_to_hex_string(const uint8_t* bytes, size_t count) { + string result; + for (unsigned int idx = 0; idx < count; ++idx) { + char buf[3]; + snprintf(buf, sizeof(buf), "%02X", bytes[idx]); + result.append(buf); + } + return result; +} + +// static +string FileID::ConvertIdentifierToUUIDString( + const wasteful_vector<uint8_t>& identifier) { + uint8_t identifier_swapped[kMDGUIDSize] = { 0 }; + + // Endian-ness swap to match dump processor expectation. + memcpy(identifier_swapped, &identifier[0], + std::min(kMDGUIDSize, identifier.size())); + uint32_t* data1 = reinterpret_cast<uint32_t*>(identifier_swapped); + *data1 = htonl(*data1); + uint16_t* data2 = reinterpret_cast<uint16_t*>(identifier_swapped + 4); + *data2 = htons(*data2); + uint16_t* data3 = reinterpret_cast<uint16_t*>(identifier_swapped + 6); + *data3 = htons(*data3); + + return bytes_to_hex_string(identifier_swapped, kMDGUIDSize); +} + +// static +string FileID::ConvertIdentifierToString( + const wasteful_vector<uint8_t>& identifier) { + return bytes_to_hex_string(&identifier[0], identifier.size()); +} + +} // elf +} // namespace google_breakpad |