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-rw-r--r--src/common/linux/crc32.cc70
-rw-r--r--src/common/linux/crc32.h53
-rw-r--r--src/common/linux/dump_symbols.cc75
3 files changed, 175 insertions, 23 deletions
diff --git a/src/common/linux/crc32.cc b/src/common/linux/crc32.cc
new file mode 100644
index 00000000..8df636ce
--- /dev/null
+++ b/src/common/linux/crc32.cc
@@ -0,0 +1,70 @@
+// Copyright 2014 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.
+
+#include "common/linux/crc32.h"
+
+namespace google_breakpad {
+
+// This implementation is based on the sample implementation in RFC 1952.
+
+// CRC32 polynomial, in reversed form.
+// See RFC 1952, or http://en.wikipedia.org/wiki/Cyclic_redundancy_check
+static const uint32_t kCrc32Polynomial = 0xEDB88320;
+static uint32_t kCrc32Table[256] = { 0 };
+
+#define arraysize(f) (sizeof(f) / sizeof(*f))
+
+static void EnsureCrc32TableInited() {
+ if (kCrc32Table[arraysize(kCrc32Table) - 1])
+ return; // already inited
+ for (uint32_t i = 0; i < arraysize(kCrc32Table); ++i) {
+ uint32_t c = i;
+ for (size_t j = 0; j < 8; ++j) {
+ if (c & 1) {
+ c = kCrc32Polynomial ^ (c >> 1);
+ } else {
+ c >>= 1;
+ }
+ }
+ kCrc32Table[i] = c;
+ }
+}
+
+uint32_t UpdateCrc32(uint32_t start, const void* buf, size_t len) {
+ EnsureCrc32TableInited();
+
+ uint32_t c = start ^ 0xFFFFFFFF;
+ const uint8_t* u = static_cast<const uint8_t*>(buf);
+ for (size_t i = 0; i < len; ++i) {
+ c = kCrc32Table[(c ^ u[i]) & 0xFF] ^ (c >> 8);
+ }
+ return c ^ 0xFFFFFFFF;
+}
+
+} // namespace google_breakpad
diff --git a/src/common/linux/crc32.h b/src/common/linux/crc32.h
new file mode 100644
index 00000000..e3d9db92
--- /dev/null
+++ b/src/common/linux/crc32.h
@@ -0,0 +1,53 @@
+// Copyright 2014 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.
+
+#ifndef COMMON_LINUX_CRC32_H_
+#define COMMON_LINUX_CRC32_H_
+
+#include <stdint.h>
+
+#include <string>
+
+namespace google_breakpad {
+
+// Updates a CRC32 checksum with |len| bytes from |buf|. |initial| holds the
+// checksum result from the previous update; for the first call, it should be 0.
+uint32_t UpdateCrc32(uint32_t initial, const void* buf, size_t len);
+
+// Computes a CRC32 checksum using |len| bytes from |buf|.
+inline uint32_t ComputeCrc32(const void* buf, size_t len) {
+ return UpdateCrc32(0, buf, len);
+}
+inline uint32_t ComputeCrc32(const std::string& str) {
+ return ComputeCrc32(str.c_str(), str.size());
+}
+
+} // namespace google_breakpad
+
+#endif // COMMON_LINUX_CRC32_H_
diff --git a/src/common/linux/dump_symbols.cc b/src/common/linux/dump_symbols.cc
index 75dcfd4c..b03bea87 100644
--- a/src/common/linux/dump_symbols.cc
+++ b/src/common/linux/dump_symbols.cc
@@ -57,6 +57,8 @@
#include "common/dwarf_cfi_to_module.h"
#include "common/dwarf_cu_to_module.h"
#include "common/dwarf_line_to_module.h"
+#include "common/linux/crc32.h"
+#include "common/linux/eintr_wrapper.h"
#include "common/linux/elfutils.h"
#include "common/linux/elfutils-inl.h"
#include "common/linux/elf_symbols_to_module.h"
@@ -141,7 +143,7 @@ class MmapWrapper {
private:
bool is_set_;
- void *base_;
+ void* base_;
size_t size_;
};
@@ -204,8 +206,8 @@ class DumperLineToModule: public DwarfCUToModule::LineToModuleHandler {
void StartCompilationUnit(const string& compilation_dir) {
compilation_dir_ = compilation_dir;
}
- void ReadProgram(const char *program, uint64 length,
- Module *module, std::vector<Module::Line> *lines) {
+ void ReadProgram(const char* program, uint64 length,
+ Module* module, std::vector<Module::Line>* lines) {
DwarfLineToModule handler(module, compilation_dir_, lines);
dwarf2reader::LineInfo parser(program, length, byte_reader_, &handler);
parser.Start();
@@ -369,7 +371,7 @@ bool LoadELF(const string& obj_file, MmapWrapper* map_wrapper,
obj_file.c_str(), strerror(errno));
return false;
}
- void *obj_base = mmap(NULL, st.st_size,
+ void* obj_base = mmap(NULL, st.st_size,
PROT_READ | PROT_WRITE, MAP_PRIVATE, obj_fd, 0);
if (obj_base == MAP_FAILED) {
fprintf(stderr, "Failed to mmap ELF file '%s': %s\n",
@@ -405,19 +407,19 @@ bool ElfEndianness(const typename ElfClass::Ehdr* elf_header,
// Read the .gnu_debuglink and get the debug file name. If anything goes
// wrong, return an empty string.
-template<typename ElfClass>
string ReadDebugLink(const char* debuglink,
- size_t debuglink_size,
+ const size_t debuglink_size,
+ const bool big_endian,
const string& obj_file,
const std::vector<string>& debug_dirs) {
- size_t debuglink_len = strlen(debuglink) + 5; // '\0' + CRC32.
- debuglink_len = 4 * ((debuglink_len + 3) / 4); // Round to nearest 4 bytes.
+ size_t debuglink_len = strlen(debuglink) + 5; // Include '\0' + CRC32.
+ debuglink_len = 4 * ((debuglink_len + 3) / 4); // Round up to 4 bytes.
// Sanity check.
if (debuglink_len != debuglink_size) {
fprintf(stderr, "Mismatched .gnu_debuglink string / section size: "
"%zx %zx\n", debuglink_len, debuglink_size);
- return "";
+ return string();
}
bool found = false;
@@ -428,10 +430,39 @@ string ReadDebugLink(const char* debuglink,
const string& debug_dir = *it;
debuglink_path = debug_dir + "/" + debuglink;
debuglink_fd = open(debuglink_path.c_str(), O_RDONLY);
- if (debuglink_fd >= 0) {
- found = true;
- break;
+ if (debuglink_fd < 0)
+ continue;
+
+ FDWrapper debuglink_fd_wrapper(debuglink_fd);
+
+ // The CRC is the last 4 bytes in |debuglink|.
+ const dwarf2reader::Endianness endianness = big_endian ?
+ dwarf2reader::ENDIANNESS_BIG : dwarf2reader::ENDIANNESS_LITTLE;
+ dwarf2reader::ByteReader byte_reader(endianness);
+ uint32_t expected_crc =
+ byte_reader.ReadFourBytes(&debuglink[debuglink_size - 4]);
+
+ uint32_t actual_crc = 0;
+ while (true) {
+ const size_t kReadSize = 4096;
+ char buf[kReadSize];
+ ssize_t bytes_read = HANDLE_EINTR(read(debuglink_fd, &buf, kReadSize));
+ if (bytes_read < 0) {
+ fprintf(stderr, "Error reading debug ELF file %s.\n",
+ debuglink_path.c_str());
+ return string();
+ }
+ if (bytes_read == 0)
+ break;
+ actual_crc = google_breakpad::UpdateCrc32(actual_crc, buf, bytes_read);
}
+ if (actual_crc != expected_crc) {
+ fprintf(stderr, "Error reading debug ELF file - CRC32 mismatch: %s\n",
+ debuglink_path.c_str());
+ continue;
+ }
+ found = true;
+ break;
}
if (!found) {
@@ -441,13 +472,9 @@ string ReadDebugLink(const char* debuglink,
const string debug_dir = *it;
fprintf(stderr, " %s/%s\n", debug_dir.c_str(), debuglink);
}
- return "";
+ return string();
}
- FDWrapper debuglink_fd_wrapper(debuglink_fd);
- // TODO(thestig) check the CRC-32 at the end of the .gnu_debuglink
- // section.
-
return debuglink_path;
}
@@ -545,7 +572,7 @@ bool LoadSymbols(const string& obj_file,
module->SetLoadAddress(loading_addr);
info->set_loading_addr(loading_addr, obj_file);
- Word debug_section_type =
+ Word debug_section_type =
elf_header->e_machine == EM_MIPS ? SHT_MIPS_DWARF : SHT_PROGBITS;
const Shdr* sections =
GetOffset<ElfClass, Shdr>(elf_header, elf_header->e_shoff);
@@ -657,10 +684,12 @@ bool LoadSymbols(const string& obj_file,
const char* debuglink_contents =
GetOffset<ElfClass, char>(elf_header,
gnu_debuglink_section->sh_offset);
- string debuglink_file
- = ReadDebugLink<ElfClass>(debuglink_contents,
- gnu_debuglink_section->sh_size,
- obj_file, info->debug_dirs());
+ string debuglink_file =
+ ReadDebugLink(debuglink_contents,
+ gnu_debuglink_section->sh_size,
+ big_endian,
+ obj_file,
+ info->debug_dirs());
info->set_debuglink_file(debuglink_file);
} else {
fprintf(stderr, ".gnu_debuglink section found in '%s', "
@@ -759,7 +788,7 @@ string FormatIdentifier(unsigned char identifier[16]) {
// last slash, or the whole filename if there are no slashes.
string BaseFileName(const string &filename) {
// Lots of copies! basename's behavior is less than ideal.
- char *c_filename = strdup(filename.c_str());
+ char* c_filename = strdup(filename.c_str());
string base = basename(c_filename);
free(c_filename);
return base;
generated by cgit v1.2.1 (git 2.18.0) at 2025-01-11 23:18:40 +0000