* character).
*/
#define ADDR_STR_LEN 20
+#define BUILD_ID_NOTE_NAME "GNU"
BT_HIDDEN
int bin_info_init(void)
bin->elf_path = g_build_path("/", target_prefix,
path, NULL);
} else {
- bin->elf_path = strdup(path);
+ bin->elf_path = g_strdup(path);
}
if (!bin->elf_path) {
bin->memsz = memsz;
bin->low_addr = low_addr;
bin->high_addr = bin->low_addr + bin->memsz;
+ bin->build_id = NULL;
+ bin->build_id_len = 0;
+ bin->file_build_id_matches = false;
return bin;
g_free(bin);
}
+/**
+ * Initialize the ELF file for a given executable.
+ *
+ * @param bin bin_info instance
+ * @returns 0 on success, negative value on error.
+ */
+static
+int bin_info_set_elf_file(struct bin_info *bin)
+{
+ int elf_fd = -1;
+ Elf *elf_file = NULL;
+
+ if (!bin) {
+ goto error;
+ }
+
+ elf_fd = open(bin->elf_path, O_RDONLY);
+ if (elf_fd < 0) {
+ elf_fd = -errno;
+ BT_LOGE("Failed to open %s\n", bin->elf_path);
+ goto error;
+ }
+
+ elf_file = elf_begin(elf_fd, ELF_C_READ, NULL);
+ if (!elf_file) {
+ BT_LOGE("elf_begin failed: %s\n", elf_errmsg(-1));
+ goto error;
+ }
+
+ if (elf_kind(elf_file) != ELF_K_ELF) {
+ BT_LOGE("Error: %s is not an ELF object\n",
+ bin->elf_path);
+ goto error;
+ }
+
+ bin->elf_fd = elf_fd;
+ bin->elf_file = elf_file;
+ return 0;
+
+error:
+ if (elf_fd >= 0) {
+ close(elf_fd);
+ elf_fd = -1;
+ }
+ elf_end(elf_file);
+ return elf_fd;
+}
+
+/**
+ * From a note section data buffer, check if it is a build id note.
+ *
+ * @param buf Pointer to a note section
+ *
+ * @returns 1 on match, 0 if `buf` does not contain a
+ * valid build id note
+ */
+static
+int is_build_id_note_section(uint8_t *buf)
+{
+ int ret = 0;
+ uint32_t name_sz, desc_sz, note_type;
+
+ /* The note section header has 3 32bit integer for the following:
+ * - Section name size
+ * - Description size
+ * - Note type
+ */
+ name_sz = (uint32_t) *buf;
+ buf += sizeof(name_sz);
+
+ buf += sizeof(desc_sz);
+
+ note_type = (uint32_t) *buf;
+ buf += sizeof(note_type);
+
+ /* Check the note type. */
+ if (note_type != NT_GNU_BUILD_ID) {
+ goto invalid;
+ }
+
+ /* Check the note name. */
+ if (memcmp(buf, BUILD_ID_NOTE_NAME, name_sz) != 0) {
+ goto invalid;
+ }
+
+ ret = 1;
+
+invalid:
+ return ret;
+}
+
+/**
+ * From a build id note section data buffer, check if the build id it contains
+ * is identical to the build id passed as parameter.
+ *
+ * @param file_build_id_note Pointer to the file build id note section.
+ * @param build_id Pointer to a build id to compare to.
+ * @param build_id_len length of the build id.
+ *
+ * @returns 1 on match, 0 otherwise.
+ */
+static
+int is_build_id_note_section_matching(uint8_t *file_build_id_note,
+ uint8_t *build_id, size_t build_id_len)
+{
+ uint32_t name_sz, desc_sz, note_type;
+
+ if (build_id_len <= 0) {
+ goto end;
+ }
+
+ /* The note section header has 3 32bit integer for the following:
+ * - Section name size
+ * - Description size
+ * - Note type
+ */
+ name_sz = (uint32_t) *file_build_id_note;
+ file_build_id_note += sizeof(name_sz);
+ file_build_id_note += sizeof(desc_sz);
+ file_build_id_note += sizeof(note_type);
+
+ /*
+ * Move the pointer pass the name char array. This corresponds to the
+ * beginning of the description section. The description is the build
+ * id in the case of a build id note.
+ */
+ file_build_id_note += name_sz;
+
+ /*
+ * Compare the binary build id with the supplied build id.
+ */
+ if (memcmp(build_id, file_build_id_note, build_id_len) == 0) {
+ return 1;
+ }
+end:
+ return 0;
+}
+
+/**
+ * Checks if the build id stored in `bin` (bin->build_id) is matching the build
+ * id of the ondisk file (bin->elf_file).
+ *
+ * @param bin bin_info instance
+ * @param build_id build id to compare ot the on disk file
+ * @param build_id_len length of the build id
+ *
+ * @returns 1 on if the build id of stored in `bin` matches
+ * the build id of the ondisk file.
+ * 0 on if they are different or an error occured.
+ */
+static
+int is_build_id_matching(struct bin_info *bin)
+{
+ int ret, is_build_id, is_matching = 0;
+ Elf_Scn *curr_section = NULL, *next_section = NULL;
+ Elf_Data *note_data = NULL;
+ GElf_Shdr *curr_section_hdr = NULL;
+
+ if (!bin->build_id) {
+ goto error;
+ }
+
+ /* Set ELF file if it hasn't been accessed yet. */
+ if (!bin->elf_file) {
+ ret = bin_info_set_elf_file(bin);
+ if (ret) {
+ /* Failed to set ELF file. */
+ goto error;
+ }
+ }
+
+ curr_section_hdr = g_new0(GElf_Shdr, 1);
+ if (!curr_section_hdr) {
+ goto error;
+ }
+
+ next_section = elf_nextscn(bin->elf_file, curr_section);
+ if (!next_section) {
+ goto error;
+ }
+
+ while (next_section) {
+ curr_section = next_section;
+ next_section = elf_nextscn(bin->elf_file, curr_section);
+
+ curr_section_hdr = gelf_getshdr(curr_section, curr_section_hdr);
+
+ if (!curr_section_hdr) {
+ goto error;
+ }
+
+ if (curr_section_hdr->sh_type != SHT_NOTE) {
+ continue;
+ }
+
+ note_data = elf_getdata(curr_section, NULL);
+ if (!note_data) {
+ goto error;
+ }
+
+ /* Check if the note is of the build-id type. */
+ is_build_id = is_build_id_note_section(note_data->d_buf);
+ if (!is_build_id) {
+ continue;
+ }
+
+ /*
+ * Compare the build id of the on-disk file and
+ * the build id recorded in the trace.
+ */
+ is_matching = is_build_id_note_section_matching(note_data->d_buf,
+ bin->build_id, bin->build_id_len);
+ if (!is_matching) {
+ break;
+ }
+ }
+error:
+ g_free(curr_section_hdr);
+ return is_matching;
+}
+
BT_HIDDEN
int bin_info_set_build_id(struct bin_info *bin, uint8_t *build_id,
size_t build_id_len)
goto error;
}
- bin->build_id = malloc(build_id_len);
+ /* Set the build id. */
+ bin->build_id = g_new0(uint8_t, build_id_len);
if (!bin->build_id) {
goto error;
}
memcpy(bin->build_id, build_id, build_id_len);
bin->build_id_len = build_id_len;
+ /*
+ * Check if the file found on the file system has the same build id
+ * that what was recorded in the trace.
+ */
+ bin->file_build_id_matches = is_build_id_matching(bin);
+ if (!bin->file_build_id_matches) {
+ BT_LOGD_STR("Supplied Build ID does not match Build ID of the "
+ "binary or library found on the file system.");
+ goto error;
+ }
+
/*
* Reset the is_elf_only flag in case it had been set
* previously, because we might find separate debug info using
return 0;
error:
-
return -1;
}
/**
* Try to set the dwarf_info for a given bin_info instance via the
- * build ID method.
+ * debug-link method.
*
* @param bin bin_info instance for which to retrieve the
* DWARF info via debug link
return ret;
}
-/**
- * Initialize the ELF file for a given executable.
- *
- * @param bin bin_info instance
- * @returns 0 on success, negative value on error.
- */
-static
-int bin_info_set_elf_file(struct bin_info *bin)
-{
- int elf_fd = -1;
- Elf *elf_file = NULL;
-
- if (!bin) {
- goto error;
- }
-
- elf_fd = open(bin->elf_path, O_RDONLY);
- if (elf_fd < 0) {
- elf_fd = -errno;
- BT_LOGD("Failed to open ELF file: path=\"%s\"", bin->elf_path);
- goto error;
- }
-
- elf_file = elf_begin(elf_fd, ELF_C_READ, NULL);
- if (!elf_file) {
- BT_LOGD("elf_begin() failed: %s.", elf_errmsg(-1));
- goto error;
- }
-
- if (elf_kind(elf_file) != ELF_K_ELF) {
- BT_LOGD("ELF file is not an ELF object: path=\"%s\"",
- bin->elf_path);
- goto error;
- }
-
- bin->elf_fd = elf_fd;
- bin->elf_file = elf_file;
- return 0;
-
-error:
- if (elf_fd >= 0) {
- close(elf_fd);
- elf_fd = -1;
- }
- elf_end(elf_file);
- return elf_fd;
-}
-
BT_HIDDEN
void source_location_destroy(struct source_location *src_loc)
{
goto error;
}
+ /*
+ * If the bin_info has a build id but it does not match the build id
+ * that was found on the file system, return an error.
+ */
+ if (bin->build_id && !bin->file_build_id_matches) {
+ goto error;
+ }
+
/* Set DWARF info if it hasn't been accessed yet. */
if (!bin->dwarf_info && !bin->is_elf_only) {
ret = bin_info_set_dwarf_info(bin);
goto error;
}
+ /*
+ * If the bin_info has a build id but it does not match the build id
+ * that was found on the file system, return an error.
+ */
+ if (bin->build_id && !bin->file_build_id_matches) {
+ goto error;
+ }
+
if (bin->is_pic) {
addr -= bin->low_addr;
ret = asprintf(&_bin_loc, "+%#0" PRIx64, addr);
goto error;
}
+ /*
+ * If the bin_info has a build id but it does not match the build id
+ * that was found on the file system, return an error.
+ */
+ if (bin->build_id && !bin->file_build_id_matches) {
+ goto error;
+ }
+
/* Set DWARF info if it hasn't been accessed yet. */
if (!bin->dwarf_info && !bin->is_elf_only) {
if (bin_info_set_dwarf_info(bin)) {
projects / babeltrace.git / blobdiff