diff options
Diffstat (limited to 'ld/ldelf.c')
| -rw-r--r-- | ld/ldelf.c | 135 |
1 files changed, 133 insertions, 2 deletions
@@ -39,6 +39,9 @@ #include <glob.h> #endif #include "ldelf.h" +#ifdef HAVE_JANSSON +#include <jansson.h> +#endif struct dt_needed { @@ -49,6 +52,9 @@ struct dt_needed /* Style of .note.gnu.build-id section. */ const char *ldelf_emit_note_gnu_build_id; +/* Content of .note.package section. */ +const char *ldelf_emit_note_fdo_package_metadata; + /* These variables are required to pass information back and forth between after_open and check_needed and stat_needed and vercheck. */ @@ -1249,7 +1255,8 @@ ldelf_after_open (int use_libpath, int native, int is_linux, int is_freebsd, } } - if (ldelf_emit_note_gnu_build_id != NULL) + if (ldelf_emit_note_gnu_build_id != NULL + || ldelf_emit_note_fdo_package_metadata != NULL) { /* Find an ELF input. */ for (abfd = link_info.input_bfds; @@ -1262,11 +1269,20 @@ ldelf_after_open (int use_libpath, int native, int is_linux, int is_freebsd, /* PR 10555: If there are no ELF input files do not try to create a .note.gnu-build-id section. */ if (abfd == NULL - || !ldelf_setup_build_id (abfd)) + || (ldelf_emit_note_gnu_build_id != NULL + && !ldelf_setup_build_id (abfd))) { free ((char *) ldelf_emit_note_gnu_build_id); ldelf_emit_note_gnu_build_id = NULL; } + + if (abfd == NULL + || (ldelf_emit_note_fdo_package_metadata != NULL + && !ldelf_setup_package_metadata (abfd))) + { + free ((char *) ldelf_emit_note_fdo_package_metadata); + ldelf_emit_note_fdo_package_metadata = NULL; + } } get_elf_backend_data (link_info.output_bfd)->setup_gnu_properties (&link_info); @@ -1501,6 +1517,121 @@ ldelf_setup_build_id (bfd *ibfd) return false; } +static bool +write_package_metadata (bfd *abfd) +{ + struct elf_obj_tdata *t = elf_tdata (abfd); + const char *json; + asection *asec; + Elf_Internal_Shdr *i_shdr; + unsigned char *contents, *json_bits; + bfd_size_type size; + file_ptr position; + Elf_External_Note *e_note; + + json = t->o->package_metadata.json; + asec = t->o->package_metadata.sec; + if (bfd_is_abs_section (asec->output_section)) + { + einfo (_("%P: warning: .note.package section discarded," + " --package-metadata ignored\n")); + return true; + } + i_shdr = &elf_section_data (asec->output_section)->this_hdr; + + if (i_shdr->contents == NULL) + { + if (asec->contents == NULL) + asec->contents = (unsigned char *) xmalloc (asec->size); + contents = asec->contents; + } + else + contents = i_shdr->contents + asec->output_offset; + + e_note = (Elf_External_Note *) contents; + size = offsetof (Elf_External_Note, name[sizeof "FDO"]); + size = (size + 3) & -(bfd_size_type) 4; + json_bits = contents + size; + size = asec->size - size; + + /* Clear the package metadata field. */ + memset (json_bits, 0, size); + + bfd_h_put_32 (abfd, sizeof "FDO", &e_note->namesz); + bfd_h_put_32 (abfd, size, &e_note->descsz); + bfd_h_put_32 (abfd, FDO_PACKAGING_METADATA, &e_note->type); + memcpy (e_note->name, "FDO", sizeof "FDO"); + memcpy (json_bits, json, strlen(json)); + + position = i_shdr->sh_offset + asec->output_offset; + size = asec->size; + return (bfd_seek (abfd, position, SEEK_SET) == 0 + && bfd_bwrite (contents, size, abfd) == size); +} + +/* Make .note.package section. + https://systemd.io/ELF_PACKAGE_METADATA/ */ + +bool +ldelf_setup_package_metadata (bfd *ibfd) +{ + asection *s; + bfd_size_type size; + size_t json_length; + flagword flags; + + /* If the option wasn't specified, silently return. */ + if (!ldelf_emit_note_fdo_package_metadata) + return false; + + /* The option was specified, but it's empty, log and return. */ + json_length = strlen (ldelf_emit_note_fdo_package_metadata); + if (json_length == 0) + { + einfo (_("%P: warning: --package-metadata is empty, ignoring\n")); + return false; + } + +#ifdef HAVE_JANSSON + json_error_t json_error; + json_t *json = json_loads (ldelf_emit_note_fdo_package_metadata, + 0, &json_error); + if (!json) + { + einfo (_("%P: warning: --package-metadata=%s does not contain valid " + "JSON, ignoring: %s\n"), + ldelf_emit_note_fdo_package_metadata, json_error.text); + return false; + } + else + json_decref (json); +#endif + + size = offsetof (Elf_External_Note, name[sizeof "FDO"]); + size += json_length + 1; + size = (size + 3) & -(bfd_size_type) 4; + + flags = (SEC_ALLOC | SEC_LOAD | SEC_IN_MEMORY + | SEC_LINKER_CREATED | SEC_READONLY | SEC_DATA); + s = bfd_make_section_anyway_with_flags (ibfd, ".note.package", + flags); + if (s != NULL && bfd_set_section_alignment (s, 2)) + { + struct elf_obj_tdata *t = elf_tdata (link_info.output_bfd); + t->o->package_metadata.after_write_object_contents + = &write_package_metadata; + t->o->package_metadata.json = ldelf_emit_note_fdo_package_metadata; + t->o->package_metadata.sec = s; + elf_section_type (s) = SHT_NOTE; + s->size = size; + return true; + } + + einfo (_("%P: warning: cannot create .note.package section," + " --package-metadata ignored\n")); + return false; +} + /* Look through an expression for an assignment statement. */ static void |