Hide lttng_ust_elf symbols
authorMichael Jeanson <mjeanson@efficios.com>
Fri, 16 Apr 2021 20:56:14 +0000 (16:56 -0400)
committerMathieu Desnoyers <mathieu.desnoyers@efficios.com>
Mon, 19 Apr 2021 17:34:37 +0000 (13:34 -0400)
Change-Id: I5747d0dd9c5fe3d2fdba4f5606e8aa1b7138016a
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
src/common/Makefile.am
src/common/elf.c [new file with mode: 0644]
src/common/elf.h
src/common/utils.c [new file with mode: 0644]
src/common/utils.h [new file with mode: 0644]
src/lib/lttng-ust/Makefile.am
src/lib/lttng-ust/lttng-tracer-core.h
src/lib/lttng-ust/lttng-ust-comm.c
src/lib/lttng-ust/lttng-ust-elf.c [deleted file]
src/lib/lttng-ust/lttng-ust-elf.h [deleted file]
tests/unit/ust-elf/Makefile.am

index a53e4ce750404f3dbe7e9c59f64a0bc2049e18fc..777764fd7750be3e00d32d3c7a823592d48fd1e4 100644 (file)
@@ -13,7 +13,6 @@ noinst_HEADERS = \
        clock.h \
        creds.h \
        dynamic-type.h \
-       elf.h \
        err-ptr.h \
        events.h \
        hash.h \
@@ -138,6 +137,8 @@ libsnprintf_la_SOURCES = \
 
 # Common library
 libcommon_la_SOURCES = \
+       elf.c \
+       elf.h \
        getenv.c \
        getenv.h \
        logging.c \
@@ -146,6 +147,8 @@ libcommon_la_SOURCES = \
        smp.h \
        strutils.c \
        strutils.h \
+       utils.c \
+       utils.h \
        patient.c
 
 libcommon_la_LIBADD = \
diff --git a/src/common/elf.c b/src/common/elf.c
new file mode 100644 (file)
index 0000000..b418176
--- /dev/null
@@ -0,0 +1,705 @@
+/*
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ *
+ * Copyright (C) 2015 Antoine Busque <abusque@efficios.com>
+ */
+
+#define _LGPL_SOURCE
+#include <fcntl.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include <lttng/ust-utils.h>
+
+#include "common/elf.h"
+#include "common/logging.h"
+#include "common/macros.h"
+#include "common/ust-fd.h"
+#include "common/utils.h"
+
+#define BUF_LEN        4096
+
+#ifndef NT_GNU_BUILD_ID
+# define NT_GNU_BUILD_ID       3
+#endif
+
+/*
+ * Retrieve the nth (where n is the `index` argument) phdr (program
+ * header) from the given elf instance.
+ *
+ * A pointer to the phdr is returned on success, NULL on failure.
+ */
+static
+struct lttng_ust_elf_phdr *lttng_ust_elf_get_phdr(struct lttng_ust_elf *elf,
+                                               uint16_t index)
+{
+       struct lttng_ust_elf_phdr *phdr = NULL;
+       off_t offset;
+
+       if (!elf) {
+               goto error;
+       }
+
+       if (index >= elf->ehdr->e_phnum) {
+               goto error;
+       }
+
+       phdr = zmalloc(sizeof(struct lttng_ust_elf_phdr));
+       if (!phdr) {
+               goto error;
+       }
+
+       offset = (off_t) elf->ehdr->e_phoff
+                       + (off_t) index * elf->ehdr->e_phentsize;
+       if (lseek(elf->fd, offset, SEEK_SET) < 0) {
+               goto error;
+       }
+
+       if (is_elf_32_bit(elf)) {
+               Elf32_Phdr elf_phdr;
+
+               if (lttng_ust_read(elf->fd, &elf_phdr, sizeof(elf_phdr))
+                               < sizeof(elf_phdr)) {
+                       goto error;
+               }
+               if (!is_elf_native_endian(elf)) {
+                       bswap_phdr(elf_phdr);
+               }
+               copy_phdr(elf_phdr, *phdr);
+       } else {
+               Elf64_Phdr elf_phdr;
+
+               if (lttng_ust_read(elf->fd, &elf_phdr, sizeof(elf_phdr))
+                               < sizeof(elf_phdr)) {
+                       goto error;
+               }
+               if (!is_elf_native_endian(elf)) {
+                       bswap_phdr(elf_phdr);
+               }
+               copy_phdr(elf_phdr, *phdr);
+       }
+
+       return phdr;
+
+error:
+       free(phdr);
+       return NULL;
+}
+
+/*
+ * Retrieve the nth (where n is the `index` argument) shdr (section
+ * header) from the given elf instance.
+ *
+ * A pointer to the shdr is returned on success, NULL on failure.
+ */
+static
+struct lttng_ust_elf_shdr *lttng_ust_elf_get_shdr(struct lttng_ust_elf *elf,
+                                               uint16_t index)
+{
+       struct lttng_ust_elf_shdr *shdr = NULL;
+       off_t offset;
+
+       if (!elf) {
+               goto error;
+       }
+
+       if (index >= elf->ehdr->e_shnum) {
+               goto error;
+       }
+
+       shdr = zmalloc(sizeof(struct lttng_ust_elf_shdr));
+       if (!shdr) {
+               goto error;
+       }
+
+       offset = (off_t) elf->ehdr->e_shoff
+                       + (off_t) index * elf->ehdr->e_shentsize;
+       if (lseek(elf->fd, offset, SEEK_SET) < 0) {
+               goto error;
+       }
+
+       if (is_elf_32_bit(elf)) {
+               Elf32_Shdr elf_shdr;
+
+               if (lttng_ust_read(elf->fd, &elf_shdr, sizeof(elf_shdr))
+                               < sizeof(elf_shdr)) {
+                       goto error;
+               }
+               if (!is_elf_native_endian(elf)) {
+                       bswap_shdr(elf_shdr);
+               }
+               copy_shdr(elf_shdr, *shdr);
+       } else {
+               Elf64_Shdr elf_shdr;
+
+               if (lttng_ust_read(elf->fd, &elf_shdr, sizeof(elf_shdr))
+                               < sizeof(elf_shdr)) {
+                       goto error;
+               }
+               if (!is_elf_native_endian(elf)) {
+                       bswap_shdr(elf_shdr);
+               }
+               copy_shdr(elf_shdr, *shdr);
+       }
+
+       return shdr;
+
+error:
+       free(shdr);
+       return NULL;
+}
+
+/*
+ * Lookup a section's name from a given offset (usually from an shdr's
+ * sh_name value) in bytes relative to the beginning of the section
+ * names string table.
+ *
+ * If no name is found, NULL is returned.
+ */
+static
+char *lttng_ust_elf_get_section_name(struct lttng_ust_elf *elf, off_t offset)
+{
+       char *name = NULL;
+       size_t len = 0, to_read;        /* len does not include \0 */
+
+       if (!elf) {
+               goto error;
+       }
+
+       if (offset >= elf->section_names_size) {
+               goto error;
+       }
+
+       if (lseek(elf->fd, elf->section_names_offset + offset, SEEK_SET) < 0) {
+               goto error;
+       }
+
+       to_read = elf->section_names_size - offset;
+
+       /* Find first \0 after or at current location, remember len. */
+       for (;;) {
+               char buf[BUF_LEN];
+               ssize_t read_len;
+               size_t i;
+
+               if (!to_read) {
+                       goto error;
+               }
+               read_len = lttng_ust_read(elf->fd, buf,
+                       min_t(size_t, BUF_LEN, to_read));
+               if (read_len <= 0) {
+                       goto error;
+               }
+               for (i = 0; i < read_len; i++) {
+                       if (buf[i] == '\0') {
+                               len += i;
+                               goto end;
+                       }
+               }
+               len += read_len;
+               to_read -= read_len;
+       }
+end:
+       name = zmalloc(sizeof(char) * (len + 1));       /* + 1 for \0 */
+       if (!name) {
+               goto error;
+       }
+       if (lseek(elf->fd, elf->section_names_offset + offset,
+               SEEK_SET) < 0) {
+               goto error;
+       }
+       if (lttng_ust_read(elf->fd, name, len + 1) < len + 1) {
+               goto error;
+       }
+
+       return name;
+
+error:
+       free(name);
+       return NULL;
+}
+
+/*
+ * Create an instance of lttng_ust_elf for the ELF file located at
+ * `path`.
+ *
+ * Return a pointer to the instance on success, NULL on failure.
+ */
+struct lttng_ust_elf *lttng_ust_elf_create(const char *path)
+{
+       uint8_t e_ident[EI_NIDENT];
+       struct lttng_ust_elf_shdr *section_names_shdr;
+       struct lttng_ust_elf *elf = NULL;
+       int ret, fd;
+
+       elf = zmalloc(sizeof(struct lttng_ust_elf));
+       if (!elf) {
+               goto error;
+       }
+
+       /* Initialize fd field to -1. 0 is a valid fd number */
+       elf->fd = -1;
+
+       elf->path = strdup(path);
+       if (!elf->path) {
+               goto error;
+       }
+
+       lttng_ust_lock_fd_tracker();
+       fd = open(elf->path, O_RDONLY | O_CLOEXEC);
+       if (fd < 0) {
+               lttng_ust_unlock_fd_tracker();
+               goto error;
+       }
+
+       ret = lttng_ust_add_fd_to_tracker(fd);
+       if (ret < 0) {
+               ret = close(fd);
+               if (ret) {
+                       PERROR("close on elf->fd");
+               }
+               ret = -1;
+               lttng_ust_unlock_fd_tracker();
+               goto error;
+       }
+       elf->fd = ret;
+       lttng_ust_unlock_fd_tracker();
+
+       if (lttng_ust_read(elf->fd, e_ident, EI_NIDENT) < EI_NIDENT) {
+               goto error;
+       }
+       elf->bitness = e_ident[EI_CLASS];
+       elf->endianness = e_ident[EI_DATA];
+
+       if (lseek(elf->fd, 0, SEEK_SET) < 0) {
+               goto error;
+       }
+
+       elf->ehdr = zmalloc(sizeof(struct lttng_ust_elf_ehdr));
+       if (!elf->ehdr) {
+               goto error;
+       }
+
+       if (is_elf_32_bit(elf)) {
+               Elf32_Ehdr elf_ehdr;
+
+               if (lttng_ust_read(elf->fd, &elf_ehdr, sizeof(elf_ehdr))
+                               < sizeof(elf_ehdr)) {
+                       goto error;
+               }
+               if (!is_elf_native_endian(elf)) {
+                       bswap_ehdr(elf_ehdr);
+               }
+               copy_ehdr(elf_ehdr, *(elf->ehdr));
+       } else {
+               Elf64_Ehdr elf_ehdr;
+
+               if (lttng_ust_read(elf->fd, &elf_ehdr, sizeof(elf_ehdr))
+                               < sizeof(elf_ehdr)) {
+                       goto error;
+               }
+               if (!is_elf_native_endian(elf)) {
+                       bswap_ehdr(elf_ehdr);
+               }
+               copy_ehdr(elf_ehdr, *(elf->ehdr));
+       }
+
+       section_names_shdr = lttng_ust_elf_get_shdr(elf, elf->ehdr->e_shstrndx);
+       if (!section_names_shdr) {
+               goto error;
+       }
+
+       elf->section_names_offset = section_names_shdr->sh_offset;
+       elf->section_names_size = section_names_shdr->sh_size;
+
+       free(section_names_shdr);
+       return elf;
+
+error:
+       lttng_ust_elf_destroy(elf);
+       return NULL;
+}
+
+/*
+ * Test whether the ELF file is position independent code (PIC)
+ */
+uint8_t lttng_ust_elf_is_pic(struct lttng_ust_elf *elf)
+{
+       /*
+        * PIC has and e_type value of ET_DYN, see ELF specification
+        * version 1.1 p. 1-3.
+        */
+       return elf->ehdr->e_type == ET_DYN;
+}
+
+/*
+ * Destroy the given lttng_ust_elf instance.
+ */
+void lttng_ust_elf_destroy(struct lttng_ust_elf *elf)
+{
+       int ret;
+
+       if (!elf) {
+               return;
+       }
+
+       if (elf->fd >= 0) {
+               lttng_ust_lock_fd_tracker();
+               ret = close(elf->fd);
+               if (!ret) {
+                       lttng_ust_delete_fd_from_tracker(elf->fd);
+               } else {
+                       PERROR("close");
+                       abort();
+               }
+               lttng_ust_unlock_fd_tracker();
+       }
+
+       free(elf->ehdr);
+       free(elf->path);
+       free(elf);
+}
+
+/*
+ * Compute the total in-memory size of the ELF file, in bytes.
+ *
+ * Returns 0 if successful, -1 if not. On success, the memory size is
+ * returned through the out parameter `memsz`.
+ */
+int lttng_ust_elf_get_memsz(struct lttng_ust_elf *elf, uint64_t *memsz)
+{
+       uint16_t i;
+       uint64_t low_addr = UINT64_MAX, high_addr = 0;
+
+       if (!elf || !memsz) {
+               goto error;
+       }
+
+       for (i = 0; i < elf->ehdr->e_phnum; ++i) {
+               struct lttng_ust_elf_phdr *phdr;
+
+               phdr = lttng_ust_elf_get_phdr(elf, i);
+               if (!phdr) {
+                       goto error;
+               }
+
+               /*
+                * Only PT_LOAD segments contribute to memsz. Skip
+                * other segments.
+                */
+               if (phdr->p_type != PT_LOAD) {
+                       goto next_loop;
+               }
+
+               low_addr = min_t(uint64_t, low_addr, phdr->p_vaddr);
+               high_addr = max_t(uint64_t, high_addr,
+                               phdr->p_vaddr + phdr->p_memsz);
+       next_loop:
+               free(phdr);
+       }
+
+       if (high_addr < low_addr) {
+               /* No PT_LOAD segments or corrupted data. */
+               goto error;
+       }
+
+       *memsz = high_addr - low_addr;
+       return 0;
+error:
+       return -1;
+}
+
+/*
+ * Internal method used to try and get the build_id from a PT_NOTE
+ * segment ranging from `offset` to `segment_end`.
+ *
+ * If the function returns successfully, the out parameter `found`
+ * indicates whether the build id information was present in the
+ * segment or not. If `found` is not 0, the out parameters `build_id`
+ * and `length` will both have been set with the retrieved
+ * information.
+ *
+ * Returns 0 on success, -1 if an error occurred.
+ */
+static
+int lttng_ust_elf_get_build_id_from_segment(
+       struct lttng_ust_elf *elf, uint8_t **build_id, size_t *length,
+       off_t offset, off_t segment_end)
+{
+       uint8_t *_build_id = NULL;      /* Silence old gcc warning. */
+       size_t _length = 0;             /* Silence old gcc warning. */
+
+       while (offset < segment_end) {
+               struct lttng_ust_elf_nhdr nhdr;
+               size_t read_len;
+
+               /* Align start of note entry */
+               offset += lttng_ust_offset_align(offset, ELF_NOTE_ENTRY_ALIGN);
+               if (offset >= segment_end) {
+                       break;
+               }
+               /*
+                * We seek manually because if the note isn't the
+                * build id the data following the header will not
+                * have been read.
+                */
+               if (lseek(elf->fd, offset, SEEK_SET) < 0) {
+                       goto error;
+               }
+               if (lttng_ust_read(elf->fd, &nhdr, sizeof(nhdr))
+                               < sizeof(nhdr)) {
+                       goto error;
+               }
+
+               if (!is_elf_native_endian(elf)) {
+                       nhdr.n_namesz = bswap_32(nhdr.n_namesz);
+                       nhdr.n_descsz = bswap_32(nhdr.n_descsz);
+                       nhdr.n_type = bswap_32(nhdr.n_type);
+               }
+
+               offset += sizeof(nhdr) + nhdr.n_namesz;
+               /* Align start of desc entry */
+               offset += lttng_ust_offset_align(offset, ELF_NOTE_DESC_ALIGN);
+
+               if (nhdr.n_type != NT_GNU_BUILD_ID) {
+                       /*
+                        * Ignore non build id notes but still
+                        * increase the offset.
+                        */
+                       offset += nhdr.n_descsz;
+                       continue;
+               }
+
+               _length = nhdr.n_descsz;
+               _build_id = zmalloc(sizeof(uint8_t) * _length);
+               if (!_build_id) {
+                       goto error;
+               }
+
+               if (lseek(elf->fd, offset, SEEK_SET) < 0) {
+                       goto error;
+               }
+               read_len = sizeof(*_build_id) * _length;
+               if (lttng_ust_read(elf->fd, _build_id, read_len) < read_len) {
+                       goto error;
+               }
+
+               break;
+       }
+
+       if (_build_id) {
+               *build_id = _build_id;
+               *length = _length;
+       }
+
+       return 0;
+error:
+       free(_build_id);
+       return -1;
+}
+
+/*
+ * Retrieve a build ID (an array of bytes) from the corresponding
+ * section in the ELF file. The length of the build ID can be either
+ * 16 or 20 bytes depending on the method used to generate it, hence
+ * the length out parameter.
+ *
+ * If the function returns successfully, the out parameter `found`
+ * indicates whether the build id information was present in the ELF
+ * file or not. If `found` is not 0, the out parameters `build_id` and
+ * `length` will both have been set with the retrieved information.
+ *
+ * Returns 0 on success, -1 if an error occurred.
+ */
+int lttng_ust_elf_get_build_id(struct lttng_ust_elf *elf, uint8_t **build_id,
+                       size_t *length, int *found)
+{
+       uint16_t i;
+       uint8_t *_build_id = NULL;      /* Silence old gcc warning. */
+       size_t _length = 0;             /* Silence old gcc warning. */
+
+       if (!elf || !build_id || !length || !found) {
+               goto error;
+       }
+
+       for (i = 0; i < elf->ehdr->e_phnum; ++i) {
+               off_t offset, segment_end;
+               struct lttng_ust_elf_phdr *phdr;
+               int ret = 0;
+
+               phdr = lttng_ust_elf_get_phdr(elf, i);
+               if (!phdr) {
+                       goto error;
+               }
+
+               /* Build ID will be contained in a PT_NOTE segment. */
+               if (phdr->p_type != PT_NOTE) {
+                       goto next_loop;
+               }
+
+               offset = phdr->p_offset;
+               segment_end = offset + phdr->p_filesz;
+               ret = lttng_ust_elf_get_build_id_from_segment(
+                       elf, &_build_id, &_length, offset, segment_end);
+       next_loop:
+               free(phdr);
+               if (ret) {
+                       goto error;
+               }
+               if (_build_id) {
+                       break;
+               }
+       }
+
+       if (_build_id) {
+               *build_id = _build_id;
+               *length = _length;
+               *found = 1;
+       } else {
+               *found = 0;
+       }
+
+       return 0;
+error:
+       free(_build_id);
+       return -1;
+}
+
+/*
+ * Try to retrieve filename and CRC from given ELF section `shdr`.
+ *
+ * If the function returns successfully, the out parameter `found`
+ * indicates whether the debug link information was present in the ELF
+ * section or not. If `found` is not 0, the out parameters `filename` and
+ * `crc` will both have been set with the retrieved information.
+ *
+ * Returns 0 on success, -1 if an error occurred.
+ */
+static
+int lttng_ust_elf_get_debug_link_from_section(struct lttng_ust_elf *elf,
+                                       char **filename, uint32_t *crc,
+                                       struct lttng_ust_elf_shdr *shdr)
+{
+       char *_filename = NULL;         /* Silence old gcc warning. */
+       size_t filename_len;
+       char *section_name = NULL;
+       uint32_t _crc = 0;              /* Silence old gcc warning. */
+
+       if (!elf || !filename || !crc || !shdr) {
+               goto error;
+       }
+
+       /*
+        * The .gnu_debuglink section is of type SHT_PROGBITS,
+        * skip the other sections.
+        */
+       if (shdr->sh_type != SHT_PROGBITS) {
+               goto end;
+       }
+
+       section_name = lttng_ust_elf_get_section_name(elf,
+                                               shdr->sh_name);
+       if (!section_name) {
+               goto end;
+       }
+       if (strcmp(section_name, ".gnu_debuglink")) {
+               goto end;
+       }
+
+       /*
+        * The length of the filename is the sh_size excluding the CRC
+        * which comes after it in the section.
+        */
+       _filename = zmalloc(sizeof(char) * (shdr->sh_size - ELF_CRC_SIZE));
+       if (!_filename) {
+               goto error;
+       }
+       if (lseek(elf->fd, shdr->sh_offset, SEEK_SET) < 0) {
+               goto error;
+       }
+       filename_len = sizeof(*_filename) * (shdr->sh_size - ELF_CRC_SIZE);
+       if (lttng_ust_read(elf->fd, _filename, filename_len) < filename_len) {
+               goto error;
+       }
+       if (lttng_ust_read(elf->fd, &_crc, sizeof(_crc)) < sizeof(_crc)) {
+               goto error;
+       }
+       if (!is_elf_native_endian(elf)) {
+               _crc = bswap_32(_crc);
+       }
+
+end:
+       free(section_name);
+       if (_filename) {
+               *filename = _filename;
+               *crc = _crc;
+       }
+
+       return 0;
+
+error:
+       free(_filename);
+       free(section_name);
+       return -1;
+}
+
+/*
+ * Retrieve filename and CRC from ELF's .gnu_debuglink section, if any.
+ *
+ * If the function returns successfully, the out parameter `found`
+ * indicates whether the debug link information was present in the ELF
+ * file or not. If `found` is not 0, the out parameters `filename` and
+ * `crc` will both have been set with the retrieved information.
+ *
+ * Returns 0 on success, -1 if an error occurred.
+ */
+int lttng_ust_elf_get_debug_link(struct lttng_ust_elf *elf, char **filename,
+                               uint32_t *crc, int *found)
+{
+       int ret;
+       uint16_t i;
+       char *_filename = NULL;         /* Silence old gcc warning. */
+       uint32_t _crc = 0;              /* Silence old gcc warning. */
+
+       if (!elf || !filename || !crc || !found) {
+               goto error;
+       }
+
+       for (i = 0; i < elf->ehdr->e_shnum; ++i) {
+               struct lttng_ust_elf_shdr *shdr = NULL;
+
+               shdr = lttng_ust_elf_get_shdr(elf, i);
+               if (!shdr) {
+                       goto error;
+               }
+
+               ret = lttng_ust_elf_get_debug_link_from_section(
+                       elf, &_filename, &_crc, shdr);
+               free(shdr);
+
+               if (ret) {
+                       goto error;
+               }
+               if (_filename) {
+                       break;
+               }
+       }
+
+       if (_filename) {
+               *filename = _filename;
+               *crc = _crc;
+               *found = 1;
+       } else {
+               *found = 0;
+       }
+
+       return 0;
+
+error:
+       free(_filename);
+       return -1;
+}
index ea0351de2933d682712c1a0e90cbeac6552c4788..17f946768c376143b8b87be53cce8596c1bc5b2e 100644 (file)
@@ -10,6 +10,9 @@
 #include <stdlib.h>
 #include <stdint.h>
 #include <stdio.h>
+#include <elf.h>
+
+#include <lttng/ust-endian.h>
 
 struct lttng_ust_elf_ehdr {
        uint16_t e_type;
@@ -67,13 +70,163 @@ struct lttng_ust_elf {
        uint8_t endianness;
 };
 
-struct lttng_ust_elf *lttng_ust_elf_create(const char *path);
-void lttng_ust_elf_destroy(struct lttng_ust_elf *elf);
-uint8_t lttng_ust_elf_is_pic(struct lttng_ust_elf *elf);
-int lttng_ust_elf_get_memsz(struct lttng_ust_elf *elf, uint64_t *memsz);
+/*
+ * Determine native endianness in order to convert when reading an ELF
+ * file if there is a mismatch.
+ */
+#if BYTE_ORDER == LITTLE_ENDIAN
+#define NATIVE_ELF_ENDIANNESS ELFDATA2LSB
+#else
+#define NATIVE_ELF_ENDIANNESS ELFDATA2MSB
+#endif
+
+/*
+ * The size in bytes of the debug link CRC as contained in an ELF
+ * section.
+ */
+#define ELF_CRC_SIZE           4
+/*
+ * ELF notes are aligned on 4 bytes. ref: ELF specification version
+ * 1.1 p. 2-5.
+ */
+#define ELF_NOTE_ENTRY_ALIGN   4
+/*
+ * Within an ELF note, the `desc` field is also aligned on 4
+ * bytes. ref: ELF specification version 1.1 p. 2-5.
+ */
+#define ELF_NOTE_DESC_ALIGN    4
+
+#define bswap(x)                               \
+       do {                                    \
+               switch (sizeof(x)) {            \
+               case 8:                         \
+                       x = bswap_64(x);        \
+                       break;                  \
+               case 4:                         \
+                       x = bswap_32(x);        \
+                       break;                  \
+               case 2:                         \
+                       x = bswap_16(x);        \
+                       break;                  \
+               case 1:                         \
+                       break;                  \
+               default:                        \
+                       abort();                \
+               }                               \
+       } while (0)
+
+#define bswap_phdr(phdr)               \
+       do {                            \
+               bswap((phdr).p_type);   \
+               bswap((phdr).p_offset); \
+               bswap((phdr).p_filesz); \
+               bswap((phdr).p_memsz);  \
+               bswap((phdr).p_align);  \
+               bswap((phdr).p_vaddr);  \
+       } while (0)
+
+#define bswap_shdr(shdr)                   \
+       do {                                \
+               bswap((shdr).sh_name);      \
+               bswap((shdr).sh_type);      \
+               bswap((shdr).sh_flags);     \
+               bswap((shdr).sh_addr);      \
+               bswap((shdr).sh_offset);    \
+               bswap((shdr).sh_size);      \
+               bswap((shdr).sh_link);      \
+               bswap((shdr).sh_info);      \
+               bswap((shdr).sh_addralign); \
+               bswap((shdr).sh_entsize);   \
+       } while (0)
+
+#define bswap_ehdr(ehdr)                               \
+       do {                                            \
+               bswap((ehdr).e_type);                   \
+               bswap((ehdr).e_machine);                \
+               bswap((ehdr).e_version);                \
+               bswap((ehdr).e_entry);                  \
+               bswap((ehdr).e_phoff);                  \
+               bswap((ehdr).e_shoff);                  \
+               bswap((ehdr).e_flags);                  \
+               bswap((ehdr).e_ehsize);                 \
+               bswap((ehdr).e_phentsize);              \
+               bswap((ehdr).e_phnum);                  \
+               bswap((ehdr).e_shentsize);              \
+               bswap((ehdr).e_shnum);                  \
+               bswap((ehdr).e_shstrndx);               \
+       } while (0)
+
+#define copy_phdr(src_phdr, dst_phdr)                          \
+       do {                                                    \
+               (dst_phdr).p_type = (src_phdr).p_type;          \
+               (dst_phdr).p_offset = (src_phdr).p_offset;      \
+               (dst_phdr).p_filesz = (src_phdr).p_filesz;      \
+               (dst_phdr).p_memsz = (src_phdr).p_memsz;        \
+               (dst_phdr).p_align = (src_phdr).p_align;        \
+               (dst_phdr).p_vaddr = (src_phdr).p_vaddr;        \
+       } while (0)
+
+#define copy_shdr(src_shdr, dst_shdr)                                  \
+       do {                                                            \
+               (dst_shdr).sh_name = (src_shdr).sh_name;                \
+               (dst_shdr).sh_type = (src_shdr).sh_type;                \
+               (dst_shdr).sh_flags = (src_shdr).sh_flags;              \
+               (dst_shdr).sh_addr = (src_shdr).sh_addr;                \
+               (dst_shdr).sh_offset = (src_shdr).sh_offset;            \
+               (dst_shdr).sh_size = (src_shdr).sh_size;                \
+               (dst_shdr).sh_link = (src_shdr).sh_link;                \
+               (dst_shdr).sh_info = (src_shdr).sh_info;                \
+               (dst_shdr).sh_addralign = (src_shdr).sh_addralign;      \
+               (dst_shdr).sh_entsize = (src_shdr).sh_entsize;          \
+       } while (0)
+
+#define copy_ehdr(src_ehdr, dst_ehdr)                                  \
+       do {                                                            \
+               (dst_ehdr).e_type = (src_ehdr).e_type;                  \
+               (dst_ehdr).e_machine = (src_ehdr).e_machine;            \
+               (dst_ehdr).e_version = (src_ehdr).e_version;            \
+               (dst_ehdr).e_entry = (src_ehdr).e_entry;                \
+               (dst_ehdr).e_phoff = (src_ehdr).e_phoff;                \
+               (dst_ehdr).e_shoff = (src_ehdr).e_shoff;                \
+               (dst_ehdr).e_flags = (src_ehdr).e_flags;                \
+               (dst_ehdr).e_ehsize = (src_ehdr).e_ehsize;              \
+               (dst_ehdr).e_phentsize = (src_ehdr).e_phentsize;        \
+               (dst_ehdr).e_phnum = (src_ehdr).e_phnum;                \
+               (dst_ehdr).e_shentsize = (src_ehdr).e_shentsize;        \
+               (dst_ehdr).e_shnum = (src_ehdr).e_shnum;                \
+               (dst_ehdr).e_shstrndx = (src_ehdr).e_shstrndx;          \
+       } while (0)
+
+static inline
+int is_elf_32_bit(struct lttng_ust_elf *elf)
+{
+       return elf->bitness == ELFCLASS32;
+}
+
+static inline
+int is_elf_native_endian(struct lttng_ust_elf *elf)
+{
+       return elf->endianness == NATIVE_ELF_ENDIANNESS;
+}
+
+struct lttng_ust_elf *lttng_ust_elf_create(const char *path)
+       __attribute__((visibility("hidden")));
+
+void lttng_ust_elf_destroy(struct lttng_ust_elf *elf)
+       __attribute__((visibility("hidden")));
+
+uint8_t lttng_ust_elf_is_pic(struct lttng_ust_elf *elf)
+       __attribute__((visibility("hidden")));
+
+int lttng_ust_elf_get_memsz(struct lttng_ust_elf *elf, uint64_t *memsz)
+       __attribute__((visibility("hidden")));
+
 int lttng_ust_elf_get_build_id(struct lttng_ust_elf *elf, uint8_t **build_id,
-                       size_t *length, int *found);
+                       size_t *length, int *found)
+       __attribute__((visibility("hidden")));
+
 int lttng_ust_elf_get_debug_link(struct lttng_ust_elf *elf, char **filename,
-                       uint32_t *crc, int *found);
+                       uint32_t *crc, int *found)
+       __attribute__((visibility("hidden")));
 
 #endif /* _UST_COMMON_ELF_H */
diff --git a/src/common/utils.c b/src/common/utils.c
new file mode 100644 (file)
index 0000000..108f76d
--- /dev/null
@@ -0,0 +1,31 @@
+/*
+ * SPDX-License-Identifier: LGPL-2.1-only
+ *
+ * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca>
+ * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ */
+
+#include <errno.h>
+#include <stdio.h>
+#include <unistd.h>
+
+#include "common/utils.h"
+
+ssize_t lttng_ust_read(int fd, void *buf, size_t len)
+{
+       ssize_t ret;
+       size_t copied = 0, to_copy = len;
+
+       do {
+               ret = read(fd, buf + copied, to_copy);
+               if (ret > 0) {
+                       copied += ret;
+                       to_copy -= ret;
+               }
+       } while ((ret > 0 && to_copy > 0)
+               || (ret < 0 && errno == EINTR));
+       if (ret > 0) {
+               ret = copied;
+       }
+       return ret;
+}
diff --git a/src/common/utils.h b/src/common/utils.h
new file mode 100644 (file)
index 0000000..31ece9e
--- /dev/null
@@ -0,0 +1,13 @@
+/*
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ *
+ * Copyright (C) 2021 Michael Jeanson <mjeanson@efficios.com>
+ */
+
+#ifndef _UST_COMMON_UTILS_H
+#define _UST_COMMON_UTILS_H
+
+ssize_t lttng_ust_read(int fd, void *buf, size_t len)
+       __attribute__((visibility("hidden")));
+
+#endif
index 4aa576bef7fa3f08894faa312d9b198a7368c145..7f82ebdec00758ae4677c4a56f47f49c91d476aa 100644 (file)
@@ -41,8 +41,6 @@ liblttng_ust_runtime_la_SOURCES = \
        lttng-context-vsgid.c \
        lttng-context.c \
        lttng-events.c \
-       lttng-ust-elf.c \
-       lttng-ust-elf.h \
        lttng-ust-statedump.c \
        lttng-ust-statedump.h \
        lttng-ust-statedump-provider.h \
index ade4636a7bee7fc78f1067e7ca58fa41eee586e9..bfead6e53c364c9389df2e3ab9cd26c7c00e467a 100644 (file)
@@ -73,9 +73,6 @@ char* lttng_ust_sockinfo_get_procname(void *owner)
 void lttng_ust_sockinfo_session_enabled(void *owner)
        __attribute__((visibility("hidden")));
 
-ssize_t lttng_ust_read(int fd, void *buf, size_t len)
-       __attribute__((visibility("hidden")));
-
 size_t lttng_ust_dummy_get_size(void *priv, size_t offset)
        __attribute__((visibility("hidden")));
 
index 2f96167e419601bf48e75c3ccc87f4b65a606ffa..c84594ba8c69408ce316eb83b3a057a11a6e7cbd 100644 (file)
@@ -357,24 +357,6 @@ static int got_timeout_env;
 
 static char *get_map_shm(struct sock_info *sock_info);
 
-ssize_t lttng_ust_read(int fd, void *buf, size_t len)
-{
-       ssize_t ret;
-       size_t copied = 0, to_copy = len;
-
-       do {
-               ret = read(fd, buf + copied, to_copy);
-               if (ret > 0) {
-                       copied += ret;
-                       to_copy -= ret;
-               }
-       } while ((ret > 0 && to_copy > 0)
-               || (ret < 0 && errno == EINTR));
-       if (ret > 0) {
-               ret = copied;
-       }
-       return ret;
-}
 /*
  * Returns the HOME directory path. Caller MUST NOT free(3) the returned
  * pointer.
diff --git a/src/lib/lttng-ust/lttng-ust-elf.c b/src/lib/lttng-ust/lttng-ust-elf.c
deleted file mode 100644 (file)
index 5980536..0000000
+++ /dev/null
@@ -1,706 +0,0 @@
-/*
- * SPDX-License-Identifier: LGPL-2.1-or-later
- *
- * Copyright (C) 2015 Antoine Busque <abusque@efficios.com>
- */
-
-#define _LGPL_SOURCE
-#include <fcntl.h>
-#include <stdbool.h>
-#include <stdint.h>
-#include <string.h>
-#include <sys/stat.h>
-#include <sys/types.h>
-#include <unistd.h>
-
-#include <lttng/ust-utils.h>
-
-#include "common/elf.h"
-#include "common/ust-fd.h"
-
-#include "lttng-tracer-core.h"
-#include "lttng-ust-elf.h"
-#include "common/macros.h"
-
-#define BUF_LEN        4096
-
-#ifndef NT_GNU_BUILD_ID
-# define NT_GNU_BUILD_ID       3
-#endif
-
-/*
- * Retrieve the nth (where n is the `index` argument) phdr (program
- * header) from the given elf instance.
- *
- * A pointer to the phdr is returned on success, NULL on failure.
- */
-static
-struct lttng_ust_elf_phdr *lttng_ust_elf_get_phdr(struct lttng_ust_elf *elf,
-                                               uint16_t index)
-{
-       struct lttng_ust_elf_phdr *phdr = NULL;
-       off_t offset;
-
-       if (!elf) {
-               goto error;
-       }
-
-       if (index >= elf->ehdr->e_phnum) {
-               goto error;
-       }
-
-       phdr = zmalloc(sizeof(struct lttng_ust_elf_phdr));
-       if (!phdr) {
-               goto error;
-       }
-
-       offset = (off_t) elf->ehdr->e_phoff
-                       + (off_t) index * elf->ehdr->e_phentsize;
-       if (lseek(elf->fd, offset, SEEK_SET) < 0) {
-               goto error;
-       }
-
-       if (is_elf_32_bit(elf)) {
-               Elf32_Phdr elf_phdr;
-
-               if (lttng_ust_read(elf->fd, &elf_phdr, sizeof(elf_phdr))
-                               < sizeof(elf_phdr)) {
-                       goto error;
-               }
-               if (!is_elf_native_endian(elf)) {
-                       bswap_phdr(elf_phdr);
-               }
-               copy_phdr(elf_phdr, *phdr);
-       } else {
-               Elf64_Phdr elf_phdr;
-
-               if (lttng_ust_read(elf->fd, &elf_phdr, sizeof(elf_phdr))
-                               < sizeof(elf_phdr)) {
-                       goto error;
-               }
-               if (!is_elf_native_endian(elf)) {
-                       bswap_phdr(elf_phdr);
-               }
-               copy_phdr(elf_phdr, *phdr);
-       }
-
-       return phdr;
-
-error:
-       free(phdr);
-       return NULL;
-}
-
-/*
- * Retrieve the nth (where n is the `index` argument) shdr (section
- * header) from the given elf instance.
- *
- * A pointer to the shdr is returned on success, NULL on failure.
- */
-static
-struct lttng_ust_elf_shdr *lttng_ust_elf_get_shdr(struct lttng_ust_elf *elf,
-                                               uint16_t index)
-{
-       struct lttng_ust_elf_shdr *shdr = NULL;
-       off_t offset;
-
-       if (!elf) {
-               goto error;
-       }
-
-       if (index >= elf->ehdr->e_shnum) {
-               goto error;
-       }
-
-       shdr = zmalloc(sizeof(struct lttng_ust_elf_shdr));
-       if (!shdr) {
-               goto error;
-       }
-
-       offset = (off_t) elf->ehdr->e_shoff
-                       + (off_t) index * elf->ehdr->e_shentsize;
-       if (lseek(elf->fd, offset, SEEK_SET) < 0) {
-               goto error;
-       }
-
-       if (is_elf_32_bit(elf)) {
-               Elf32_Shdr elf_shdr;
-
-               if (lttng_ust_read(elf->fd, &elf_shdr, sizeof(elf_shdr))
-                               < sizeof(elf_shdr)) {
-                       goto error;
-               }
-               if (!is_elf_native_endian(elf)) {
-                       bswap_shdr(elf_shdr);
-               }
-               copy_shdr(elf_shdr, *shdr);
-       } else {
-               Elf64_Shdr elf_shdr;
-
-               if (lttng_ust_read(elf->fd, &elf_shdr, sizeof(elf_shdr))
-                               < sizeof(elf_shdr)) {
-                       goto error;
-               }
-               if (!is_elf_native_endian(elf)) {
-                       bswap_shdr(elf_shdr);
-               }
-               copy_shdr(elf_shdr, *shdr);
-       }
-
-       return shdr;
-
-error:
-       free(shdr);
-       return NULL;
-}
-
-/*
- * Lookup a section's name from a given offset (usually from an shdr's
- * sh_name value) in bytes relative to the beginning of the section
- * names string table.
- *
- * If no name is found, NULL is returned.
- */
-static
-char *lttng_ust_elf_get_section_name(struct lttng_ust_elf *elf, off_t offset)
-{
-       char *name = NULL;
-       size_t len = 0, to_read;        /* len does not include \0 */
-
-       if (!elf) {
-               goto error;
-       }
-
-       if (offset >= elf->section_names_size) {
-               goto error;
-       }
-
-       if (lseek(elf->fd, elf->section_names_offset + offset, SEEK_SET) < 0) {
-               goto error;
-       }
-
-       to_read = elf->section_names_size - offset;
-
-       /* Find first \0 after or at current location, remember len. */
-       for (;;) {
-               char buf[BUF_LEN];
-               ssize_t read_len;
-               size_t i;
-
-               if (!to_read) {
-                       goto error;
-               }
-               read_len = lttng_ust_read(elf->fd, buf,
-                       min_t(size_t, BUF_LEN, to_read));
-               if (read_len <= 0) {
-                       goto error;
-               }
-               for (i = 0; i < read_len; i++) {
-                       if (buf[i] == '\0') {
-                               len += i;
-                               goto end;
-                       }
-               }
-               len += read_len;
-               to_read -= read_len;
-       }
-end:
-       name = zmalloc(sizeof(char) * (len + 1));       /* + 1 for \0 */
-       if (!name) {
-               goto error;
-       }
-       if (lseek(elf->fd, elf->section_names_offset + offset,
-               SEEK_SET) < 0) {
-               goto error;
-       }
-       if (lttng_ust_read(elf->fd, name, len + 1) < len + 1) {
-               goto error;
-       }
-
-       return name;
-
-error:
-       free(name);
-       return NULL;
-}
-
-/*
- * Create an instance of lttng_ust_elf for the ELF file located at
- * `path`.
- *
- * Return a pointer to the instance on success, NULL on failure.
- */
-struct lttng_ust_elf *lttng_ust_elf_create(const char *path)
-{
-       uint8_t e_ident[EI_NIDENT];
-       struct lttng_ust_elf_shdr *section_names_shdr;
-       struct lttng_ust_elf *elf = NULL;
-       int ret, fd;
-
-       elf = zmalloc(sizeof(struct lttng_ust_elf));
-       if (!elf) {
-               goto error;
-       }
-
-       /* Initialize fd field to -1. 0 is a valid fd number */
-       elf->fd = -1;
-
-       elf->path = strdup(path);
-       if (!elf->path) {
-               goto error;
-       }
-
-       lttng_ust_lock_fd_tracker();
-       fd = open(elf->path, O_RDONLY | O_CLOEXEC);
-       if (fd < 0) {
-               lttng_ust_unlock_fd_tracker();
-               goto error;
-       }
-
-       ret = lttng_ust_add_fd_to_tracker(fd);
-       if (ret < 0) {
-               ret = close(fd);
-               if (ret) {
-                       PERROR("close on elf->fd");
-               }
-               ret = -1;
-               lttng_ust_unlock_fd_tracker();
-               goto error;
-       }
-       elf->fd = ret;
-       lttng_ust_unlock_fd_tracker();
-
-       if (lttng_ust_read(elf->fd, e_ident, EI_NIDENT) < EI_NIDENT) {
-               goto error;
-       }
-       elf->bitness = e_ident[EI_CLASS];
-       elf->endianness = e_ident[EI_DATA];
-
-       if (lseek(elf->fd, 0, SEEK_SET) < 0) {
-               goto error;
-       }
-
-       elf->ehdr = zmalloc(sizeof(struct lttng_ust_elf_ehdr));
-       if (!elf->ehdr) {
-               goto error;
-       }
-
-       if (is_elf_32_bit(elf)) {
-               Elf32_Ehdr elf_ehdr;
-
-               if (lttng_ust_read(elf->fd, &elf_ehdr, sizeof(elf_ehdr))
-                               < sizeof(elf_ehdr)) {
-                       goto error;
-               }
-               if (!is_elf_native_endian(elf)) {
-                       bswap_ehdr(elf_ehdr);
-               }
-               copy_ehdr(elf_ehdr, *(elf->ehdr));
-       } else {
-               Elf64_Ehdr elf_ehdr;
-
-               if (lttng_ust_read(elf->fd, &elf_ehdr, sizeof(elf_ehdr))
-                               < sizeof(elf_ehdr)) {
-                       goto error;
-               }
-               if (!is_elf_native_endian(elf)) {
-                       bswap_ehdr(elf_ehdr);
-               }
-               copy_ehdr(elf_ehdr, *(elf->ehdr));
-       }
-
-       section_names_shdr = lttng_ust_elf_get_shdr(elf, elf->ehdr->e_shstrndx);
-       if (!section_names_shdr) {
-               goto error;
-       }
-
-       elf->section_names_offset = section_names_shdr->sh_offset;
-       elf->section_names_size = section_names_shdr->sh_size;
-
-       free(section_names_shdr);
-       return elf;
-
-error:
-       lttng_ust_elf_destroy(elf);
-       return NULL;
-}
-
-/*
- * Test whether the ELF file is position independent code (PIC)
- */
-uint8_t lttng_ust_elf_is_pic(struct lttng_ust_elf *elf)
-{
-       /*
-        * PIC has and e_type value of ET_DYN, see ELF specification
-        * version 1.1 p. 1-3.
-        */
-       return elf->ehdr->e_type == ET_DYN;
-}
-
-/*
- * Destroy the given lttng_ust_elf instance.
- */
-void lttng_ust_elf_destroy(struct lttng_ust_elf *elf)
-{
-       int ret;
-
-       if (!elf) {
-               return;
-       }
-
-       if (elf->fd >= 0) {
-               lttng_ust_lock_fd_tracker();
-               ret = close(elf->fd);
-               if (!ret) {
-                       lttng_ust_delete_fd_from_tracker(elf->fd);
-               } else {
-                       PERROR("close");
-                       abort();
-               }
-               lttng_ust_unlock_fd_tracker();
-       }
-
-       free(elf->ehdr);
-       free(elf->path);
-       free(elf);
-}
-
-/*
- * Compute the total in-memory size of the ELF file, in bytes.
- *
- * Returns 0 if successful, -1 if not. On success, the memory size is
- * returned through the out parameter `memsz`.
- */
-int lttng_ust_elf_get_memsz(struct lttng_ust_elf *elf, uint64_t *memsz)
-{
-       uint16_t i;
-       uint64_t low_addr = UINT64_MAX, high_addr = 0;
-
-       if (!elf || !memsz) {
-               goto error;
-       }
-
-       for (i = 0; i < elf->ehdr->e_phnum; ++i) {
-               struct lttng_ust_elf_phdr *phdr;
-
-               phdr = lttng_ust_elf_get_phdr(elf, i);
-               if (!phdr) {
-                       goto error;
-               }
-
-               /*
-                * Only PT_LOAD segments contribute to memsz. Skip
-                * other segments.
-                */
-               if (phdr->p_type != PT_LOAD) {
-                       goto next_loop;
-               }
-
-               low_addr = min_t(uint64_t, low_addr, phdr->p_vaddr);
-               high_addr = max_t(uint64_t, high_addr,
-                               phdr->p_vaddr + phdr->p_memsz);
-       next_loop:
-               free(phdr);
-       }
-
-       if (high_addr < low_addr) {
-               /* No PT_LOAD segments or corrupted data. */
-               goto error;
-       }
-
-       *memsz = high_addr - low_addr;
-       return 0;
-error:
-       return -1;
-}
-
-/*
- * Internal method used to try and get the build_id from a PT_NOTE
- * segment ranging from `offset` to `segment_end`.
- *
- * If the function returns successfully, the out parameter `found`
- * indicates whether the build id information was present in the
- * segment or not. If `found` is not 0, the out parameters `build_id`
- * and `length` will both have been set with the retrieved
- * information.
- *
- * Returns 0 on success, -1 if an error occurred.
- */
-static
-int lttng_ust_elf_get_build_id_from_segment(
-       struct lttng_ust_elf *elf, uint8_t **build_id, size_t *length,
-       off_t offset, off_t segment_end)
-{
-       uint8_t *_build_id = NULL;      /* Silence old gcc warning. */
-       size_t _length = 0;             /* Silence old gcc warning. */
-
-       while (offset < segment_end) {
-               struct lttng_ust_elf_nhdr nhdr;
-               size_t read_len;
-
-               /* Align start of note entry */
-               offset += lttng_ust_offset_align(offset, ELF_NOTE_ENTRY_ALIGN);
-               if (offset >= segment_end) {
-                       break;
-               }
-               /*
-                * We seek manually because if the note isn't the
-                * build id the data following the header will not
-                * have been read.
-                */
-               if (lseek(elf->fd, offset, SEEK_SET) < 0) {
-                       goto error;
-               }
-               if (lttng_ust_read(elf->fd, &nhdr, sizeof(nhdr))
-                               < sizeof(nhdr)) {
-                       goto error;
-               }
-
-               if (!is_elf_native_endian(elf)) {
-                       nhdr.n_namesz = bswap_32(nhdr.n_namesz);
-                       nhdr.n_descsz = bswap_32(nhdr.n_descsz);
-                       nhdr.n_type = bswap_32(nhdr.n_type);
-               }
-
-               offset += sizeof(nhdr) + nhdr.n_namesz;
-               /* Align start of desc entry */
-               offset += lttng_ust_offset_align(offset, ELF_NOTE_DESC_ALIGN);
-
-               if (nhdr.n_type != NT_GNU_BUILD_ID) {
-                       /*
-                        * Ignore non build id notes but still
-                        * increase the offset.
-                        */
-                       offset += nhdr.n_descsz;
-                       continue;
-               }
-
-               _length = nhdr.n_descsz;
-               _build_id = zmalloc(sizeof(uint8_t) * _length);
-               if (!_build_id) {
-                       goto error;
-               }
-
-               if (lseek(elf->fd, offset, SEEK_SET) < 0) {
-                       goto error;
-               }
-               read_len = sizeof(*_build_id) * _length;
-               if (lttng_ust_read(elf->fd, _build_id, read_len) < read_len) {
-                       goto error;
-               }
-
-               break;
-       }
-
-       if (_build_id) {
-               *build_id = _build_id;
-               *length = _length;
-       }
-
-       return 0;
-error:
-       free(_build_id);
-       return -1;
-}
-
-/*
- * Retrieve a build ID (an array of bytes) from the corresponding
- * section in the ELF file. The length of the build ID can be either
- * 16 or 20 bytes depending on the method used to generate it, hence
- * the length out parameter.
- *
- * If the function returns successfully, the out parameter `found`
- * indicates whether the build id information was present in the ELF
- * file or not. If `found` is not 0, the out parameters `build_id` and
- * `length` will both have been set with the retrieved information.
- *
- * Returns 0 on success, -1 if an error occurred.
- */
-int lttng_ust_elf_get_build_id(struct lttng_ust_elf *elf, uint8_t **build_id,
-                       size_t *length, int *found)
-{
-       uint16_t i;
-       uint8_t *_build_id = NULL;      /* Silence old gcc warning. */
-       size_t _length = 0;             /* Silence old gcc warning. */
-
-       if (!elf || !build_id || !length || !found) {
-               goto error;
-       }
-
-       for (i = 0; i < elf->ehdr->e_phnum; ++i) {
-               off_t offset, segment_end;
-               struct lttng_ust_elf_phdr *phdr;
-               int ret = 0;
-
-               phdr = lttng_ust_elf_get_phdr(elf, i);
-               if (!phdr) {
-                       goto error;
-               }
-
-               /* Build ID will be contained in a PT_NOTE segment. */
-               if (phdr->p_type != PT_NOTE) {
-                       goto next_loop;
-               }
-
-               offset = phdr->p_offset;
-               segment_end = offset + phdr->p_filesz;
-               ret = lttng_ust_elf_get_build_id_from_segment(
-                       elf, &_build_id, &_length, offset, segment_end);
-       next_loop:
-               free(phdr);
-               if (ret) {
-                       goto error;
-               }
-               if (_build_id) {
-                       break;
-               }
-       }
-
-       if (_build_id) {
-               *build_id = _build_id;
-               *length = _length;
-               *found = 1;
-       } else {
-               *found = 0;
-       }
-
-       return 0;
-error:
-       free(_build_id);
-       return -1;
-}
-
-/*
- * Try to retrieve filename and CRC from given ELF section `shdr`.
- *
- * If the function returns successfully, the out parameter `found`
- * indicates whether the debug link information was present in the ELF
- * section or not. If `found` is not 0, the out parameters `filename` and
- * `crc` will both have been set with the retrieved information.
- *
- * Returns 0 on success, -1 if an error occurred.
- */
-static
-int lttng_ust_elf_get_debug_link_from_section(struct lttng_ust_elf *elf,
-                                       char **filename, uint32_t *crc,
-                                       struct lttng_ust_elf_shdr *shdr)
-{
-       char *_filename = NULL;         /* Silence old gcc warning. */
-       size_t filename_len;
-       char *section_name = NULL;
-       uint32_t _crc = 0;              /* Silence old gcc warning. */
-
-       if (!elf || !filename || !crc || !shdr) {
-               goto error;
-       }
-
-       /*
-        * The .gnu_debuglink section is of type SHT_PROGBITS,
-        * skip the other sections.
-        */
-       if (shdr->sh_type != SHT_PROGBITS) {
-               goto end;
-       }
-
-       section_name = lttng_ust_elf_get_section_name(elf,
-                                               shdr->sh_name);
-       if (!section_name) {
-               goto end;
-       }
-       if (strcmp(section_name, ".gnu_debuglink")) {
-               goto end;
-       }
-
-       /*
-        * The length of the filename is the sh_size excluding the CRC
-        * which comes after it in the section.
-        */
-       _filename = zmalloc(sizeof(char) * (shdr->sh_size - ELF_CRC_SIZE));
-       if (!_filename) {
-               goto error;
-       }
-       if (lseek(elf->fd, shdr->sh_offset, SEEK_SET) < 0) {
-               goto error;
-       }
-       filename_len = sizeof(*_filename) * (shdr->sh_size - ELF_CRC_SIZE);
-       if (lttng_ust_read(elf->fd, _filename, filename_len) < filename_len) {
-               goto error;
-       }
-       if (lttng_ust_read(elf->fd, &_crc, sizeof(_crc)) < sizeof(_crc)) {
-               goto error;
-       }
-       if (!is_elf_native_endian(elf)) {
-               _crc = bswap_32(_crc);
-       }
-
-end:
-       free(section_name);
-       if (_filename) {
-               *filename = _filename;
-               *crc = _crc;
-       }
-
-       return 0;
-
-error:
-       free(_filename);
-       free(section_name);
-       return -1;
-}
-
-/*
- * Retrieve filename and CRC from ELF's .gnu_debuglink section, if any.
- *
- * If the function returns successfully, the out parameter `found`
- * indicates whether the debug link information was present in the ELF
- * file or not. If `found` is not 0, the out parameters `filename` and
- * `crc` will both have been set with the retrieved information.
- *
- * Returns 0 on success, -1 if an error occurred.
- */
-int lttng_ust_elf_get_debug_link(struct lttng_ust_elf *elf, char **filename,
-                               uint32_t *crc, int *found)
-{
-       int ret;
-       uint16_t i;
-       char *_filename = NULL;         /* Silence old gcc warning. */
-       uint32_t _crc = 0;              /* Silence old gcc warning. */
-
-       if (!elf || !filename || !crc || !found) {
-               goto error;
-       }
-
-       for (i = 0; i < elf->ehdr->e_shnum; ++i) {
-               struct lttng_ust_elf_shdr *shdr = NULL;
-
-               shdr = lttng_ust_elf_get_shdr(elf, i);
-               if (!shdr) {
-                       goto error;
-               }
-
-               ret = lttng_ust_elf_get_debug_link_from_section(
-                       elf, &_filename, &_crc, shdr);
-               free(shdr);
-
-               if (ret) {
-                       goto error;
-               }
-               if (_filename) {
-                       break;
-               }
-       }
-
-       if (_filename) {
-               *filename = _filename;
-               *crc = _crc;
-               *found = 1;
-       } else {
-               *found = 0;
-       }
-
-       return 0;
-
-error:
-       free(_filename);
-       return -1;
-}
diff --git a/src/lib/lttng-ust/lttng-ust-elf.h b/src/lib/lttng-ust/lttng-ust-elf.h
deleted file mode 100644 (file)
index b052e2a..0000000
+++ /dev/null
@@ -1,152 +0,0 @@
-/*
- * SPDX-License-Identifier: LGPL-2.1-or-later
- *
- * Copyright (C) 2015 Antoine Busque <abusque@efficios.com>
- */
-
-#ifndef _LIB_LTTNG_UST_ELF_H
-#define _LIB_LTTNG_UST_ELF_H
-
-#include <elf.h>
-#include <lttng/ust-endian.h>
-
-/*
- * Determine native endianness in order to convert when reading an ELF
- * file if there is a mismatch.
- */
-#if BYTE_ORDER == LITTLE_ENDIAN
-#define NATIVE_ELF_ENDIANNESS ELFDATA2LSB
-#else
-#define NATIVE_ELF_ENDIANNESS ELFDATA2MSB
-#endif
-
-/*
- * The size in bytes of the debug link CRC as contained in an ELF
- * section.
- */
-#define ELF_CRC_SIZE           4
-/*
- * ELF notes are aligned on 4 bytes. ref: ELF specification version
- * 1.1 p. 2-5.
- */
-#define ELF_NOTE_ENTRY_ALIGN   4
-/*
- * Within an ELF note, the `desc` field is also aligned on 4
- * bytes. ref: ELF specification version 1.1 p. 2-5.
- */
-#define ELF_NOTE_DESC_ALIGN    4
-
-#define bswap(x)                               \
-       do {                                    \
-               switch (sizeof(x)) {            \
-               case 8:                         \
-                       x = bswap_64(x);        \
-                       break;                  \
-               case 4:                         \
-                       x = bswap_32(x);        \
-                       break;                  \
-               case 2:                         \
-                       x = bswap_16(x);        \
-                       break;                  \
-               case 1:                         \
-                       break;                  \
-               default:                        \
-                       abort();                \
-               }                               \
-       } while (0)
-
-#define bswap_phdr(phdr)               \
-       do {                            \
-               bswap((phdr).p_type);   \
-               bswap((phdr).p_offset); \
-               bswap((phdr).p_filesz); \
-               bswap((phdr).p_memsz);  \
-               bswap((phdr).p_align);  \
-               bswap((phdr).p_vaddr);  \
-       } while (0)
-
-#define bswap_shdr(shdr)                   \
-       do {                                \
-               bswap((shdr).sh_name);      \
-               bswap((shdr).sh_type);      \
-               bswap((shdr).sh_flags);     \
-               bswap((shdr).sh_addr);      \
-               bswap((shdr).sh_offset);    \
-               bswap((shdr).sh_size);      \
-               bswap((shdr).sh_link);      \
-               bswap((shdr).sh_info);      \
-               bswap((shdr).sh_addralign); \
-               bswap((shdr).sh_entsize);   \
-       } while (0)
-
-#define bswap_ehdr(ehdr)                               \
-       do {                                            \
-               bswap((ehdr).e_type);                   \
-               bswap((ehdr).e_machine);                \
-               bswap((ehdr).e_version);                \
-               bswap((ehdr).e_entry);                  \
-               bswap((ehdr).e_phoff);                  \
-               bswap((ehdr).e_shoff);                  \
-               bswap((ehdr).e_flags);                  \
-               bswap((ehdr).e_ehsize);                 \
-               bswap((ehdr).e_phentsize);              \
-               bswap((ehdr).e_phnum);                  \
-               bswap((ehdr).e_shentsize);              \
-               bswap((ehdr).e_shnum);                  \
-               bswap((ehdr).e_shstrndx);               \
-       } while (0)
-
-#define copy_phdr(src_phdr, dst_phdr)                          \
-       do {                                                    \
-               (dst_phdr).p_type = (src_phdr).p_type;          \
-               (dst_phdr).p_offset = (src_phdr).p_offset;      \
-               (dst_phdr).p_filesz = (src_phdr).p_filesz;      \
-               (dst_phdr).p_memsz = (src_phdr).p_memsz;        \
-               (dst_phdr).p_align = (src_phdr).p_align;        \
-               (dst_phdr).p_vaddr = (src_phdr).p_vaddr;        \
-       } while (0)
-
-#define copy_shdr(src_shdr, dst_shdr)                                  \
-       do {                                                            \
-               (dst_shdr).sh_name = (src_shdr).sh_name;                \
-               (dst_shdr).sh_type = (src_shdr).sh_type;                \
-               (dst_shdr).sh_flags = (src_shdr).sh_flags;              \
-               (dst_shdr).sh_addr = (src_shdr).sh_addr;                \
-               (dst_shdr).sh_offset = (src_shdr).sh_offset;            \
-               (dst_shdr).sh_size = (src_shdr).sh_size;                \
-               (dst_shdr).sh_link = (src_shdr).sh_link;                \
-               (dst_shdr).sh_info = (src_shdr).sh_info;                \
-               (dst_shdr).sh_addralign = (src_shdr).sh_addralign;      \
-               (dst_shdr).sh_entsize = (src_shdr).sh_entsize;          \
-       } while (0)
-
-#define copy_ehdr(src_ehdr, dst_ehdr)                                  \
-       do {                                                            \
-               (dst_ehdr).e_type = (src_ehdr).e_type;                  \
-               (dst_ehdr).e_machine = (src_ehdr).e_machine;            \
-               (dst_ehdr).e_version = (src_ehdr).e_version;            \
-               (dst_ehdr).e_entry = (src_ehdr).e_entry;                \
-               (dst_ehdr).e_phoff = (src_ehdr).e_phoff;                \
-               (dst_ehdr).e_shoff = (src_ehdr).e_shoff;                \
-               (dst_ehdr).e_flags = (src_ehdr).e_flags;                \
-               (dst_ehdr).e_ehsize = (src_ehdr).e_ehsize;              \
-               (dst_ehdr).e_phentsize = (src_ehdr).e_phentsize;        \
-               (dst_ehdr).e_phnum = (src_ehdr).e_phnum;                \
-               (dst_ehdr).e_shentsize = (src_ehdr).e_shentsize;        \
-               (dst_ehdr).e_shnum = (src_ehdr).e_shnum;                \
-               (dst_ehdr).e_shstrndx = (src_ehdr).e_shstrndx;          \
-       } while (0)
-
-static inline
-int is_elf_32_bit(struct lttng_ust_elf *elf)
-{
-       return elf->bitness == ELFCLASS32;
-}
-
-static inline
-int is_elf_native_endian(struct lttng_ust_elf *elf)
-{
-       return elf->endianness == NATIVE_ELF_ENDIANNESS;
-}
-
-#endif
index b7480556248763fd422abff5d404bdd9fd2f97b5..b469453c99a91e4e22bb052d84935ad3b96d7d6f 100644 (file)
@@ -5,7 +5,8 @@ AM_CPPFLAGS += -I$(top_srcdir)/tests/utils
 noinst_PROGRAMS = ust-elf
 ust_elf_SOURCES = ust-elf.c
 ust_elf_LDADD = \
-       $(top_builddir)/src/lib/lttng-ust/liblttng-ust.la \
+       $(top_builddir)/src/common/libcommon.la \
+       $(top_builddir)/src/lib/lttng-ust-common/liblttng-ust-common.la \
        $(top_builddir)/tests/utils/libtap.a
 
 dist_check_SCRIPTS = test_ust_elf
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