| /* |
| * Copyright (c) 2015 Cisco and/or its affiliates. |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at: |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| /* |
| Copyright (c) 2008 Eliot Dresselhaus |
| |
| Permission is hereby granted, free of charge, to any person obtaining |
| a copy of this software and associated documentation files (the |
| "Software"), to deal in the Software without restriction, including |
| without limitation the rights to use, copy, modify, merge, publish, |
| distribute, sublicense, and/or sell copies of the Software, and to |
| permit persons to whom the Software is furnished to do so, subject to |
| the following conditions: |
| |
| The above copyright notice and this permission notice shall be |
| included in all copies or substantial portions of the Software. |
| |
| THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, |
| EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF |
| MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND |
| NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE |
| LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION |
| OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION |
| WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. |
| */ |
| |
| #include <vppinfra/elf.h> |
| |
| #include <sys/types.h> |
| #include <sys/stat.h> |
| #include <fcntl.h> |
| |
| #ifndef CLIB_UNIX |
| #error "unix only" |
| #endif |
| |
| typedef struct { |
| elf_main_t elf_main; |
| char * input_file; |
| char * output_file; |
| char * set_interpreter; |
| char * set_rpath; |
| int unset_rpath; |
| int verbose; |
| int quiet; |
| int allow_elf_shared; |
| /* for use in the optimized / simplified case */ |
| u64 file_size; |
| u64 interpreter_offset; |
| u64 rpath_offset; |
| } elf_tool_main_t; |
| |
| static clib_error_t * elf_set_interpreter (elf_main_t * em, |
| elf_tool_main_t * tm) |
| { |
| elf_segment_t * g; |
| elf_section_t * s; |
| clib_error_t * error; |
| char * interp = tm->set_interpreter; |
| |
| switch (em->first_header.file_type) |
| { |
| case ELF_EXEC: |
| break; |
| |
| case ELF_SHARED: |
| if (tm->allow_elf_shared) |
| break; |
| /* Note flowthrough */ |
| default: |
| return clib_error_return (0, "unacceptable file_type"); |
| } |
| |
| vec_foreach (g, em->segments) |
| { |
| if (g->header.type == ELF_SEGMENT_INTERP) |
| break; |
| } |
| |
| if (g >= vec_end (em->segments)) |
| return clib_error_return (0, "interpreter not found"); |
| |
| if (g->header.memory_size < 1 + strlen (interp)) |
| return clib_error_return (0, "given interpreter does not fit; must be less than %d bytes (`%s' given)", |
| g->header.memory_size, interp); |
| |
| error = elf_get_section_by_start_address (em, g->header.virtual_address, &s); |
| if (error) |
| return error; |
| |
| /* Put in new null terminated string. */ |
| memset (s->contents, 0, vec_len (s->contents)); |
| memcpy (s->contents, interp, strlen (interp)); |
| |
| return 0; |
| } |
| |
| static void |
| delete_rpath_for_section (elf_main_t * em, elf_section_t * s) |
| { |
| elf64_dynamic_entry_t * e; |
| elf64_dynamic_entry_t * new_es = 0; |
| |
| vec_foreach (e, em->dynamic_entries) |
| { |
| switch (e->type) |
| { |
| case ELF_DYNAMIC_ENTRY_RPATH: |
| case ELF_DYNAMIC_ENTRY_RUN_PATH: |
| break; |
| |
| default: |
| vec_add1 (new_es, e[0]); |
| break; |
| } |
| } |
| |
| /* Pad so as to keep section size constant. */ |
| { |
| elf64_dynamic_entry_t e_end; |
| e_end.type = ELF_DYNAMIC_ENTRY_END; |
| e_end.data = 0; |
| while (vec_len (new_es) < vec_len (em->dynamic_entries)) |
| vec_add1 (new_es, e_end); |
| } |
| |
| vec_free (em->dynamic_entries); |
| em->dynamic_entries = new_es; |
| |
| elf_set_dynamic_entries (em); |
| } |
| |
| static void delete_rpath (elf_main_t * em) |
| { |
| elf_section_t * s; |
| |
| vec_foreach (s, em->sections) |
| { |
| switch (s->header.type) |
| { |
| case ELF_SECTION_DYNAMIC: |
| delete_rpath_for_section (em, s); |
| break; |
| |
| default: |
| break; |
| } |
| } |
| } |
| |
| static clib_error_t * |
| set_rpath_for_section (elf_main_t * em, elf_section_t * s, char * new_rpath) |
| { |
| elf64_dynamic_entry_t * e; |
| char * old_rpath; |
| int old_len, new_len = strlen (new_rpath); |
| u8 * new_string_table = vec_dup (em->dynamic_string_table); |
| |
| vec_foreach (e, em->dynamic_entries) |
| { |
| switch (e->type) |
| { |
| case ELF_DYNAMIC_ENTRY_RPATH: |
| case ELF_DYNAMIC_ENTRY_RUN_PATH: |
| old_rpath = (char *) new_string_table + e->data; |
| old_len = strlen (old_rpath); |
| if (old_len < new_len) |
| return clib_error_return (0, "rpath of `%s' does not fit (old rpath `%s')", |
| new_rpath, old_rpath); |
| strcpy (old_rpath, new_rpath); |
| break; |
| |
| default: |
| break; |
| } |
| } |
| |
| elf_set_section_contents (em, em->dynamic_string_table_section_index, |
| new_string_table, |
| vec_bytes (new_string_table)); |
| |
| return 0; |
| } |
| |
| static clib_error_t * |
| set_rpath (elf_main_t * em, char * rpath) |
| { |
| clib_error_t * error = 0; |
| elf_section_t * s; |
| |
| vec_foreach (s, em->sections) |
| { |
| switch (s->header.type) |
| { |
| case ELF_SECTION_DYNAMIC: |
| error = set_rpath_for_section (em, s, rpath); |
| if (error) |
| return error; |
| break; |
| |
| default: |
| break; |
| } |
| } |
| |
| return error; |
| } |
| |
| static clib_error_t * |
| set_interpreter_rpath (elf_tool_main_t * tm) |
| { |
| int ifd = -1, ofd = -1; |
| struct stat fd_stat; |
| u8 *idp = 0; /* warning be gone */ |
| u64 mmap_length = 0, i; |
| u32 run_length; |
| u8 in_run; |
| u64 offset0 = 0, offset1 = 0; |
| clib_error_t * error; |
| int fix_in_place = 0; |
| |
| if (!strcmp (tm->input_file, tm->output_file)) |
| fix_in_place = 1; |
| |
| ifd = open (tm->input_file, O_RDWR); |
| if (ifd < 0) |
| { |
| error = clib_error_return_unix (0, "open `%s'", tm->input_file); |
| goto done; |
| } |
| |
| if (fstat (ifd, &fd_stat) < 0) |
| { |
| error = clib_error_return_unix (0, "fstat `%s'", tm->input_file); |
| goto done; |
| } |
| |
| if (!(fd_stat.st_mode & S_IFREG)) |
| { |
| error = clib_error_return (0, "%s is not a regular file", tm->input_file); |
| goto done; |
| } |
| |
| mmap_length = fd_stat.st_size; |
| if (mmap_length < 4) |
| { |
| error = clib_error_return (0, "%s too short", tm->input_file); |
| goto done; |
| } |
| |
| /* COW-mapping, since we intend to write the fixups */ |
| if (fix_in_place) |
| idp = mmap (0, mmap_length, PROT_READ | PROT_WRITE, MAP_SHARED, |
| ifd, /* offset */ 0); |
| else |
| idp = mmap (0, mmap_length, PROT_READ | PROT_WRITE, MAP_PRIVATE, |
| ifd, /* offset */ 0); |
| if (~pointer_to_uword (idp) == 0) |
| { |
| mmap_length = 0; |
| error = clib_error_return_unix (0, "mmap `%s'", tm->input_file); |
| goto done; |
| } |
| |
| if (idp[0] != 0x7f || idp[1] != 'E' || idp[2] != 'L' || idp[3] != 'F') |
| { |
| error = clib_error_return (0, "not an ELF file '%s'", tm->input_file); |
| goto done; |
| } |
| |
| in_run = 0; |
| run_length = 0; |
| |
| for (i = 0; i < mmap_length; i++) |
| { |
| if (idp[i] == '/') |
| { |
| if (in_run) |
| run_length++; |
| else |
| { |
| in_run = 1; |
| run_length = 1; |
| } |
| } |
| else |
| { |
| if (in_run && run_length >= 16) |
| { |
| if (offset0 == 0) |
| offset0 = (i - run_length); |
| else if (offset1 == 0) |
| { |
| offset1 = (i - run_length); |
| goto found_both; |
| } |
| } |
| in_run = 0; |
| run_length = 0; |
| } |
| } |
| |
| if (offset0 == 0) |
| { |
| error = clib_error_return (0, "no fixup markers in %s", |
| tm->input_file); |
| goto done; |
| } |
| |
| found_both: |
| if (0) |
| clib_warning ("offset0 %lld (0x%llx), offset1 %lld (0x%llx)", |
| offset0, offset0, offset1, offset1); |
| |
| /* Executable file case */ |
| if (offset0 && offset1) |
| { |
| tm->interpreter_offset = offset0; |
| tm->rpath_offset = offset1; |
| } |
| else /* shared library case */ |
| { |
| tm->interpreter_offset = 0; |
| tm->rpath_offset = offset0; |
| } |
| |
| if (tm->interpreter_offset) |
| memcpy (&idp[tm->interpreter_offset], tm->set_interpreter, |
| strlen (tm->set_interpreter)+1); |
| |
| if (tm->rpath_offset) |
| memcpy (&idp[tm->rpath_offset], tm->set_rpath, |
| strlen (tm->set_rpath)+1); |
| |
| /* Write the output file... */ |
| if (fix_in_place == 0) |
| { |
| ofd = open (tm->output_file, O_RDWR | O_CREAT | O_TRUNC, 0644); |
| if (ofd < 0) |
| { |
| error = clib_error_return_unix (0, "create `%s'", tm->output_file); |
| goto done; |
| } |
| |
| if (write (ofd, idp, mmap_length) != mmap_length) |
| error = clib_error_return_unix (0, "write `%s'", tm->output_file); |
| } |
| |
| done: |
| if (mmap_length > 0) |
| munmap (idp, mmap_length); |
| close (ifd); |
| close (ofd); |
| return error; |
| } |
| |
| |
| int main (int argc, char * argv[]) |
| { |
| elf_tool_main_t _tm, * tm = &_tm; |
| elf_main_t * em = &tm->elf_main; |
| unformat_input_t i; |
| clib_error_t * error = 0; |
| |
| memset (tm, 0, sizeof (tm[0])); |
| unformat_init_command_line (&i, argv); |
| |
| while (unformat_check_input (&i) != UNFORMAT_END_OF_INPUT) |
| { |
| if (unformat (&i, "in %s", &tm->input_file)) |
| ; |
| else if (unformat (&i, "out %s", &tm->output_file)) |
| ; |
| else if (unformat (&i, "set-interpreter %s", &tm->set_interpreter)) |
| ; |
| else if (unformat (&i, "set-rpath %s", &tm->set_rpath)) |
| ; |
| else if (unformat (&i, "unset-rpath")) |
| tm->unset_rpath = 1; |
| else if (unformat (&i, "verbose")) |
| tm->verbose = ~0; |
| else if (unformat (&i, "verbose-symbols")) |
| tm->verbose |= FORMAT_ELF_MAIN_SYMBOLS; |
| else if (unformat (&i, "verbose-relocations")) |
| tm->verbose |= FORMAT_ELF_MAIN_RELOCATIONS; |
| else if (unformat (&i, "verbose-dynamic")) |
| tm->verbose |= FORMAT_ELF_MAIN_DYNAMIC; |
| else if (unformat (&i, "quiet")) |
| tm->quiet = 1; |
| else if (unformat (&i, "allow-elf-shared")) |
| tm->allow_elf_shared = 1; |
| else |
| { |
| error = unformat_parse_error (&i); |
| goto done; |
| } |
| } |
| |
| if (! tm->input_file) |
| clib_error ("no input file"); |
| |
| /* Do the typical case a stone-simple way... */ |
| if (tm->quiet && tm->set_interpreter && tm->set_rpath && tm->output_file) |
| { |
| error = set_interpreter_rpath (tm); |
| goto done; |
| } |
| |
| error = elf_read_file (em, tm->input_file); |
| |
| if (error) |
| goto done; |
| |
| if (tm->verbose) |
| fformat (stdout, "%U", format_elf_main, em, tm->verbose); |
| |
| if (tm->set_interpreter) |
| { |
| error = elf_set_interpreter (em, tm); |
| if (error) |
| goto done; |
| } |
| |
| if (tm->set_rpath) |
| { |
| error = set_rpath (em, tm->set_rpath); |
| if (error) |
| goto done; |
| } |
| |
| if (tm->unset_rpath) |
| delete_rpath (em); |
| |
| if (tm->output_file) |
| error = elf_write_file (em, tm->output_file); |
| |
| elf_main_free (em); |
| |
| done: |
| if (error) |
| { |
| if (tm->quiet == 0) |
| clib_error_report (error); |
| return 1; |
| } |
| else |
| return 0; |
| } |