#include "gold.h"
+#include <cerrno>
#include <cstring>
#include <algorithm>
#include <iostream>
#include <utility>
+#include <fcntl.h>
+#include <unistd.h>
+#include "libiberty.h"
+#include "md5.h"
+#include "sha1.h"
#include "parameters.h"
#include "options.h"
unattached_section_list_(), special_output_list_(),
section_headers_(NULL), tls_segment_(NULL), symtab_section_(NULL),
dynsym_section_(NULL), dynamic_section_(NULL), dynamic_data_(NULL),
- eh_frame_section_(NULL), group_signatures_(), output_file_size_(-1),
+ eh_frame_section_(NULL), eh_frame_data_(NULL), eh_frame_hdr_section_(NULL),
+ build_id_note_(NULL), group_signatures_(), output_file_size_(-1),
input_requires_executable_stack_(false),
input_with_gnu_stack_note_(false),
input_without_gnu_stack_note_(false),
this->create_gold_note();
this->create_executable_stack_info(target);
+ this->create_build_id();
Output_segment* phdr_seg = NULL;
if (!parameters->options().relocatable() && !parameters->doing_static_link())
return off;
}
-// Create a .note section for an executable or shared library. This
-// records the version of gold used to create the binary.
+// Create a note header following the format defined in the ELF ABI.
+// NAME is the name, NOTE_TYPE is the type, DESCSZ is the size of the
+// descriptor. ALLOCATE is true if the section should be allocated in
+// memory. This returns the new note section. It sets
+// *TRAILING_PADDING to the number of trailing zero bytes required.
-void
-Layout::create_gold_note()
+Output_section*
+Layout::create_note(const char* name, int note_type, size_t descsz,
+ bool allocate, size_t* trailing_padding)
{
- if (parameters->options().relocatable())
- return;
-
// Authorities all agree that the values in a .note field should
// be aligned on 4-byte boundaries for 32-bit binaries. However,
// they differ on what the alignment is for 64-bit binaries.
#endif
// The contents of the .note section.
- const char* name = "GNU";
- std::string desc(std::string("gold ") + gold::get_version_string());
size_t namesz = strlen(name) + 1;
size_t aligned_namesz = align_address(namesz, size / 8);
- size_t descsz = desc.length() + 1;
size_t aligned_descsz = align_address(descsz, size / 8);
- const int note_type = 4;
- size_t notesz = 3 * (size / 8) + aligned_namesz + aligned_descsz;
+ size_t notehdrsz = 3 * (size / 8) + aligned_namesz;
- unsigned char buffer[128];
- gold_assert(sizeof buffer >= notesz);
- memset(buffer, 0, notesz);
+ unsigned char* buffer = new unsigned char[notehdrsz];
+ memset(buffer, 0, notehdrsz);
bool is_big_endian = parameters->target().is_big_endian();
gold_unreachable();
memcpy(buffer + 3 * (size / 8), name, namesz);
- memcpy(buffer + 3 * (size / 8) + aligned_namesz, desc.data(), descsz);
const char* note_name = this->namepool_.add(".note", false, NULL);
+ elfcpp::Elf_Xword flags = 0;
+ if (allocate)
+ flags = elfcpp::SHF_ALLOC;
Output_section* os = this->make_output_section(note_name,
elfcpp::SHT_NOTE,
- 0);
- Output_section_data* posd = new Output_data_const(buffer, notesz,
- size / 8);
+ flags);
+ Output_section_data* posd = new Output_data_const_buffer(buffer, notehdrsz,
+ size / 8);
+ os->add_output_section_data(posd);
+
+ *trailing_padding = aligned_descsz - descsz;
+
+ return os;
+}
+
+// For an executable or shared library, create a note to record the
+// version of gold used to create the binary.
+
+void
+Layout::create_gold_note()
+{
+ if (parameters->options().relocatable())
+ return;
+
+ std::string desc = std::string("gold ") + gold::get_version_string();
+
+ size_t trailing_padding;
+ Output_section *os = this->create_note("GNU", elfcpp::NT_GNU_GOLD_VERSION,
+ desc.size(), false, &trailing_padding);
+
+ Output_section_data* posd = new Output_data_const(desc, 4);
os->add_output_section_data(posd);
+
+ if (trailing_padding > 0)
+ {
+ posd = new Output_data_fixed_space(trailing_padding, 0);
+ os->add_output_section_data(posd);
+ }
}
// Record whether the stack should be executable. This can be set
}
}
+// If --build-id was used, set up the build ID note.
+
+void
+Layout::create_build_id()
+{
+ if (!parameters->options().user_set_build_id())
+ return;
+
+ const char* style = parameters->options().build_id();
+ if (strcmp(style, "none") == 0)
+ return;
+
+ // Set DESCSZ to the size of the note descriptor. When possible,
+ // set DESC to the note descriptor contents.
+ size_t descsz;
+ std::string desc;
+ if (strcmp(style, "md5") == 0)
+ descsz = 128 / 8;
+ else if (strcmp(style, "sha1") == 0)
+ descsz = 160 / 8;
+ else if (strcmp(style, "uuid") == 0)
+ {
+ const size_t uuidsz = 128 / 8;
+
+ char buffer[uuidsz];
+ memset(buffer, 0, uuidsz);
+
+ int descriptor = ::open("/dev/urandom", O_RDONLY);
+ if (descriptor < 0)
+ gold_error(_("--build-id=uuid failed: could not open /dev/urandom: %s"),
+ strerror(errno));
+ else
+ {
+ ssize_t got = ::read(descriptor, buffer, uuidsz);
+ ::close(descriptor);
+ if (got < 0)
+ gold_error(_("/dev/urandom: read failed: %s"), strerror(errno));
+ else if (static_cast<size_t>(got) != uuidsz)
+ gold_error(_("/dev/urandom: expected %zu bytes, got %zd bytes"),
+ uuidsz, got);
+ }
+
+ desc.assign(buffer, uuidsz);
+ descsz = uuidsz;
+ }
+ else if (strncmp(style, "0x", 2) == 0)
+ {
+ hex_init();
+ const char* p = style + 2;
+ while (*p != '\0')
+ {
+ if (hex_p(p[0]) && hex_p(p[1]))
+ {
+ char c = (hex_value(p[0]) << 4) | hex_value(p[1]);
+ desc += c;
+ p += 2;
+ }
+ else if (*p == '-' || *p == ':')
+ ++p;
+ else
+ gold_fatal(_("--build-id argument '%s' not a valid hex number"),
+ style);
+ }
+ descsz = desc.size();
+ }
+ else
+ gold_fatal(_("unrecognized --build-id argument '%s'"), style);
+
+ // Create the note.
+ size_t trailing_padding;
+ Output_section* os = this->create_note("GNU", elfcpp::NT_GNU_BUILD_ID,
+ descsz, true, &trailing_padding);
+
+ if (!desc.empty())
+ {
+ // We know the value already, so we fill it in now.
+ gold_assert(desc.size() == descsz);
+
+ Output_section_data* posd = new Output_data_const(desc, 4);
+ os->add_output_section_data(posd);
+
+ if (trailing_padding != 0)
+ {
+ posd = new Output_data_fixed_space(trailing_padding, 0);
+ os->add_output_section_data(posd);
+ }
+ }
+ else
+ {
+ // We need to compute a checksum after we have completed the
+ // link.
+ gold_assert(trailing_padding == 0);
+ this->build_id_note_ = new Output_data_fixed_space(descsz, 4);
+ os->add_output_section_data(this->build_id_note_);
+ os->set_after_input_sections();
+ }
+}
+
// Return whether SEG1 should be before SEG2 in the output file. This
// is based entirely on the segment type and flags. When this is
// called the segment addresses has normally not yet been set.
this->section_headers_->write(of);
}
+// If the build ID requires computing a checksum, do so here, and
+// write it out. We compute a checksum over the entire file because
+// that is simplest.
+
+void
+Layout::write_build_id(Output_file* of) const
+{
+ if (this->build_id_note_ == NULL)
+ return;
+
+ const unsigned char* iv = of->get_input_view(0, this->output_file_size_);
+
+ unsigned char* ov = of->get_output_view(this->build_id_note_->offset(),
+ this->build_id_note_->data_size());
+
+ const char* style = parameters->options().build_id();
+ if (strcmp(style, "sha1") == 0)
+ {
+ sha1_ctx ctx;
+ sha1_init_ctx(&ctx);
+ sha1_process_bytes(iv, this->output_file_size_, &ctx);
+ sha1_finish_ctx(&ctx, ov);
+ }
+ else if (strcmp(style, "md5") == 0)
+ {
+ md5_ctx ctx;
+ md5_init_ctx(&ctx);
+ md5_process_bytes(iv, this->output_file_size_, &ctx);
+ md5_finish_ctx(&ctx, ov);
+ }
+ else
+ gold_unreachable();
+
+ of->write_output_view(this->build_id_note_->offset(),
+ this->build_id_note_->data_size(),
+ ov);
+
+ of->free_input_view(0, this->output_file_size_, iv);
+}
+
// Write out a binary file. This is called after the link is
// complete. IN is the temporary output file we used to generate the
// ELF code. We simply walk through the segments, read them from
void
Close_task_runner::run(Workqueue*, const Task*)
{
+ // If we need to compute a checksum for the BUILD if, we do so here.
+ this->layout_->write_build_id(this->of_);
+
// If we've been asked to create a binary file, we do so here.
if (this->options_->oformat_enum() != General_options::OBJECT_FORMAT_ELF)
this->layout_->write_binary(this->of_);
projects / deliverable / binutils-gdb.git / commitdiff
