On Wed Nov 11, 2020 at 1:53 PM HST, Rui Salvaterra wrote: > Drop our local sstrip copy and use the current ELFKickers upstream > version. > Patch the original makefile in order to avoid building elftoc, since it > fails > with musl's elf.h. This is fine, since we only need sstrip anyway. > Finally, add the possibility to pass additional arguments to sstrip (-z > being > the obvious candidate). > > Signed-off-by: Rui Salvaterra <rsalvate...@gmail.com>
LGTM, tested and works fine. Could you please create a slightly more verbose patch name for 001-compile.patch? Do you see any possible success in pinging upstream to unify their versioning? sstrip 3.1a still outputs version 2.0. Please create an additional patch to enable -z by default. > --- > config/Config-build.in | 8 + > rules.mk | 2 +- > tools/sstrip/Makefile | 15 +- > tools/sstrip/patches/001-compile.patch | 19 + > tools/sstrip/src/sstrip.c | 466 ------------------------- > 5 files changed, 36 insertions(+), 474 deletions(-) > create mode 100644 tools/sstrip/patches/001-compile.patch > delete mode 100644 tools/sstrip/src/sstrip.c > > diff --git a/config/Config-build.in b/config/Config-build.in > index 178afbdb94..c54bc243c5 100644 > --- a/config/Config-build.in > +++ b/config/Config-build.in > @@ -182,6 +182,14 @@ menu "Global build settings" > help > Specifies arguments passed to the strip command when stripping binaries. > > + config SSTRIP_ARGS > + string > + prompt "Sstrip arguments" > + depends on USE_SSTRIP > + default "" > + help > + Specifies arguments passed to the sstrip command when stripping > binaries. > + > config STRIP_KERNEL_EXPORTS > bool "Strip unnecessary exports from the kernel image" > help > diff --git a/rules.mk b/rules.mk > index e416126030..5c1c141c11 100644 > --- a/rules.mk > +++ b/rules.mk > @@ -328,7 +328,7 @@ else > STRIP:=$(TARGET_CROSS)strip $(call qstrip,$(CONFIG_STRIP_ARGS)) > else > ifneq ($(CONFIG_USE_SSTRIP),) > - STRIP:=$(STAGING_DIR_HOST)/bin/sstrip > + STRIP:=$(STAGING_DIR_HOST)/bin/sstrip $(call > qstrip,$(CONFIG_SSTRIP_ARGS)) > endif > endif > RSTRIP= \ > diff --git a/tools/sstrip/Makefile b/tools/sstrip/Makefile > index bab172a95a..590d183db0 100644 > --- a/tools/sstrip/Makefile > +++ b/tools/sstrip/Makefile > @@ -6,18 +6,19 @@ > # > include $(TOPDIR)/rules.mk > > -PKG_NAME:=sstrip > -PKG_VERSION:=2.0 > +PKG_NAME:=ELFkickers > +PKG_VERSION:=3.1a > + > +PKG_SOURCE_URL:=https://www.muppetlabs.com/~breadbox/pub/software > +PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.gz > +PKG_HASH:=06430880aaf4919c5f99fc629da7000347421668c2cf32bced2d401aac276508 > + > PKG_RELEASE:=1 > > include $(INCLUDE_DIR)/host-build.mk > > -define Host/Compile > - $(HOSTCC) $(HOST_CFLAGS) -include endian.h -o $(HOST_BUILD_DIR)/sstrip > src/sstrip.c > -endef > - > define Host/Install > - $(CP) $(HOST_BUILD_DIR)/sstrip $(STAGING_DIR_HOST)/bin/ > + $(CP) $(HOST_BUILD_DIR)/bin/sstrip $(STAGING_DIR_HOST)/bin/ > endef > > define Host/Clean > diff --git a/tools/sstrip/patches/001-compile.patch > b/tools/sstrip/patches/001-compile.patch > new file mode 100644 > index 0000000000..9d3346edfb > --- /dev/null > +++ b/tools/sstrip/patches/001-compile.patch > @@ -0,0 +1,19 @@ > +--- a/Makefile > ++++ b/Makefile > +@@ -2,7 +2,7 @@ > + > + prefix = /usr/local > + > +-PROGRAMS = elfls objres rebind sstrip elftoc ebfc infect > ++PROGRAMS = elfls objres rebind sstrip ebfc infect > + > + all: $(PROGRAMS) > + > +@@ -19,7 +19,6 @@ elfls: bin/elfls doc/elfls.1 > + objres: bin/objres doc/objres.1 > + rebind: bin/rebind doc/rebind.1 > + sstrip: bin/sstrip doc/sstrip.1 > +-elftoc: bin/elftoc doc/elftoc.1 > + ebfc: bin/ebfc doc/ebfc.1 > + infect: bin/infect doc/infect.1 > + > diff --git a/tools/sstrip/src/sstrip.c b/tools/sstrip/src/sstrip.c > deleted file mode 100644 > index 12cf12e095..0000000000 > --- a/tools/sstrip/src/sstrip.c > +++ /dev/null > @@ -1,466 +0,0 @@ > -/* http://www.muppetlabs.com/~breadbox/software/elfkickers.html */ > - > -/* sstrip: Copyright (C) 1999-2001 by Brian Raiter, under the GNU > - * General Public License. No warranty. See COPYING for details. > - * > - * Aug 23, 2004 Hacked by Manuel Novoa III <m...@codepoet.org> to > - * handle targets of different endianness and/or elf class, making > - * it more useful in a cross-devel environment. > - */ > - > -/* ============== original README =================== > - * > - * sstrip is a small utility that removes the contents at the end of an > - * ELF file that are not part of the program's memory image. > - * > - * Most ELF executables are built with both a program header table and > a > - * section header table. However, only the former is required in order > - * for the OS to load, link and execute a program. sstrip attempts to > - * extract the ELF header, the program header table, and its contents, > - * leaving everything else in the bit bucket. It can only remove parts > of > - * the file that occur at the end, after the parts to be saved. > However, > - * this almost always includes the section header table, and > occasionally > - * a few random sections that are not used when running a program. > - * > - * It should be noted that the GNU bfd library is (understandably) > - * dependent on the section header table as an index to the file's > - * contents. Thus, an executable file that has no section header table > - * cannot be used with gdb, objdump, or any other program based upon > the > - * bfd library, at all. In fact, the program will not even recognize > the > - * file as a valid executable. (This limitation is noted in the source > - * code comments for bfd, and is marked "FIXME", so this may change at > - * some future date. However, I would imagine that it is a pretty > - * low-priority item, as executables without a section header table are > - * rare in the extreme.) This probably also explains why strip doesn't > - * offer the option to do this. > - * > - * Shared library files may also have their section header table > removed. > - * Such a library will still function; however, it will no longer be > - * possible for a compiler to link a new program against it. > - * > - * As an added bonus, sstrip also tries to removes trailing zero bytes > - * from the end of the file. (This normally cannot be done with an > - * executable that has a section header table.) > - * > - * sstrip is a very simplistic program. It depends upon the common > - * practice of putting the parts of the file that contribute to the > - * memory image at the front, and the remaining material at the end. > This > - * permits it to discard the latter material without affecting file > - * offsets and memory addresses in what remains. Of course, the ELF > - * standard permits files to be organized in almost any order, so if a > - * pathological linker decided to put its section headers at the top, > - * sstrip would be useless on such executables. > - */ > - > -#include <stdio.h> > -#include <stdlib.h> > -#include <string.h> > -#include <errno.h> > -#include <unistd.h> > -#include <fcntl.h> > -#include <elf.h> > -#include <byteswap.h> > - > -#ifndef TRUE > -#define TRUE 1 > -#define FALSE 0 > -#endif > - > -/* The name of the program. > - */ > -static char const *progname; > - > -/* The name of the current file. > - */ > -static char const *filename; > - > - > -/* A simple error-handling function. FALSE is always returned for the > - * convenience of the caller. > - */ > -static int err(char const *errmsg) > -{ > - fprintf(stderr, "%s: %s: %s\n", progname, filename, errmsg); > - return FALSE; > -} > - > -/* A flag to signal the need for endian reversal. > - */ > -static int do_reverse_endian; > - > -/* Get a value from the elf header, compensating for endianness. > - */ > -#define EGET(X) \ > - (__extension__ ({ \ > - uint64_t __res; \ > - if (!do_reverse_endian) { \ > - __res = (X); \ > - } else if (sizeof(X) == 1) { \ > - __res = (X); \ > - } else if (sizeof(X) == 2) { \ > - __res = bswap_16((X)); \ > - } else if (sizeof(X) == 4) { \ > - __res = bswap_32((X)); \ > - } else if (sizeof(X) == 8) { \ > - __res = bswap_64((X)); \ > - } else { \ > - fprintf(stderr, "%s: %s: EGET failed for size %zu\n", \ > - progname, filename, sizeof(X)); \ > - exit(EXIT_FAILURE); \ > - } \ > - __res; \ > - })) > - > -/* Set a value 'Y' in the elf header to 'X', compensating for > endianness. > - */ > -#define ESET(Y,X) \ > - do if (!do_reverse_endian) { \ > - Y = (X); \ > - } else if (sizeof(Y) == 1) { \ > - Y = (X); \ > - } else if (sizeof(Y) == 2) { \ > - Y = bswap_16((uint16_t)(X)); \ > - } else if (sizeof(Y) == 4) { \ > - Y = bswap_32((uint32_t)(X)); \ > - } else if (sizeof(Y) == 8) { \ > - Y = bswap_64((uint64_t)(X)); \ > - } else { \ > - fprintf(stderr, "%s: %s: ESET failed for size %zu\n", \ > - progname, filename, sizeof(Y)); \ > - exit(EXIT_FAILURE); \ > - } while (0) > - > - > -/* A macro for I/O errors: The given error message is used only when > - * errno is not set. > - */ > -#define ferr(msg) (err(errno ? strerror(errno) : (msg))) > - > - > - > -#define HEADER_FUNCTIONS(CLASS) \ > - \ > -/* readelfheader() reads the ELF header into our global variable, and \ > - * checks to make sure that this is in fact a file that we should be \ > - * munging. \ > - */ \ > -static int readelfheader ## CLASS (int fd, Elf ## CLASS ## _Ehdr *ehdr) > \ > -{ \ > - if (read(fd, ((char *)ehdr)+EI_NIDENT, sizeof(*ehdr) - EI_NIDENT) \ > - != sizeof(*ehdr) - EI_NIDENT) \ > - return ferr("missing or incomplete ELF header."); \ > - \ > - /* Verify the sizes of the ELF header and the program segment \ > - * header table entries. \ > - */ \ > - if (EGET(ehdr->e_ehsize) != sizeof(Elf ## CLASS ## _Ehdr)) \ > - return err("unrecognized ELF header size."); \ > - if (EGET(ehdr->e_phentsize) != sizeof(Elf ## CLASS ## _Phdr)) \ > - return err("unrecognized program segment header size."); \ > - \ > - /* Finally, check the file type. \ > - */ \ > - if (EGET(ehdr->e_type) != ET_EXEC && EGET(ehdr->e_type) != ET_DYN) \ > - return err("not an executable or shared-object library."); \ > - \ > - return TRUE; \ > -} \ > - \ > -/* readphdrtable() loads the program segment header table into memory. > \ > - */ \ > -static int readphdrtable ## CLASS (int fd, Elf ## CLASS ## _Ehdr const > *ehdr, \ > - Elf ## CLASS ## _Phdr **phdrs) \ > -{ \ > - size_t size; \ > - \ > - if (!EGET(ehdr->e_phoff) || !EGET(ehdr->e_phnum) \ > -) return err("ELF file has no program header table."); \ > - \ > - size = EGET(ehdr->e_phnum) * sizeof **phdrs; \ > - if (!(*phdrs = malloc(size))) \ > - return err("Out of memory!"); \ > - \ > - errno = 0; \ > - if (read(fd, *phdrs, size) != (ssize_t)size) \ > - return ferr("missing or incomplete program segment header table."); \ > - \ > - return TRUE; \ > -} \ > - \ > -/* getmemorysize() determines the offset of the last byte of the file \ > - * that is referenced by an entry in the program segment header table. > \ > - * (Anything in the file after that point is not used when the program > \ > - * is executing, and thus can be safely discarded.) \ > - */ \ > -static int getmemorysize ## CLASS (Elf ## CLASS ## _Ehdr const *ehdr, \ > - Elf ## CLASS ## _Phdr const *phdrs, \ > - unsigned long *newsize) \ > -{ \ > - Elf ## CLASS ## _Phdr const *phdr; \ > - unsigned long size, n; \ > - size_t i; \ > - \ > - /* Start by setting the size to include the ELF header and the \ > - * complete program segment header table. \ > - */ \ > - size = EGET(ehdr->e_phoff) + EGET(ehdr->e_phnum) * sizeof *phdrs; \ > - if (size < sizeof *ehdr) \ > - size = sizeof *ehdr; \ > - \ > - /* Then keep extending the size to include whatever data the \ > - * program segment header table references. \ > - */ \ > - for (i = 0, phdr = phdrs ; i < EGET(ehdr->e_phnum) ; ++i, ++phdr) { \ > - if (EGET(phdr->p_type) != PT_NULL) { \ > - n = EGET(phdr->p_offset) + EGET(phdr->p_filesz); \ > - if (n > size) \ > - size = n; \ > - } \ > - } \ > - \ > - *newsize = size; \ > - return TRUE; \ > -} \ > - \ > -/* modifyheaders() removes references to the section header table if \ > - * it was stripped, and reduces program header table entries that \ > - * included truncated bytes at the end of the file. \ > - */ \ > -static int modifyheaders ## CLASS (Elf ## CLASS ## _Ehdr *ehdr, \ > - Elf ## CLASS ## _Phdr *phdrs, \ > - unsigned long newsize) \ > -{ \ > - Elf ## CLASS ## _Phdr *phdr; \ > - size_t i; \ > - \ > - /* If the section header table is gone, then remove all references \ > - * to it in the ELF header. \ > - */ \ > - if (EGET(ehdr->e_shoff) >= newsize) { \ > - ESET(ehdr->e_shoff,0); \ > - ESET(ehdr->e_shnum,0); \ > - ESET(ehdr->e_shentsize,0); \ > - ESET(ehdr->e_shstrndx,0); \ > - } \ > - \ > - /* The program adjusts the file size of any segment that was \ > - * truncated. The case of a segment being completely stripped out \ > - * is handled separately. \ > - */ \ > - for (i = 0, phdr = phdrs ; i < EGET(ehdr->e_phnum) ; ++i, ++phdr) { \ > - if (EGET(phdr->p_offset) >= newsize) { \ > - ESET(phdr->p_offset,newsize); \ > - ESET(phdr->p_filesz,0); \ > - } else if (EGET(phdr->p_offset) + EGET(phdr->p_filesz) > newsize) { \ > - ESET(phdr->p_filesz, newsize - EGET(phdr->p_offset)); \ > - } \ > - } \ > - \ > - return TRUE; \ > -} \ > - \ > -/* commitchanges() writes the new headers back to the original file \ > - * and sets the file to its new size. \ > - */ \ > -static int commitchanges ## CLASS (int fd, Elf ## CLASS ## _Ehdr const > *ehdr, \ > - Elf ## CLASS ## _Phdr *phdrs, \ > - unsigned long newsize) \ > -{ \ > - size_t n; \ > - \ > - /* Save the changes to the ELF header, if any. \ > - */ \ > - if (lseek(fd, 0, SEEK_SET)) \ > - return ferr("could not rewind file"); \ > - errno = 0; \ > - if (write(fd, ehdr, sizeof *ehdr) != sizeof *ehdr) \ > - return err("could not modify file"); \ > - \ > - /* Save the changes to the program segment header table, if any. \ > - */ \ > - if (lseek(fd, EGET(ehdr->e_phoff), SEEK_SET) == (off_t)-1) { \ > - err("could not seek in file."); \ > - goto warning; \ > - } \ > - n = EGET(ehdr->e_phnum) * sizeof *phdrs; \ > - if (write(fd, phdrs, n) != (ssize_t)n) { \ > - err("could not write to file"); \ > - goto warning; \ > - } \ > - \ > - /* Eleventh-hour sanity check: don't truncate before the end of \ > - * the program segment header table. \ > - */ \ > - if (newsize < EGET(ehdr->e_phoff) + n) \ > - newsize = EGET(ehdr->e_phoff) + n; \ > - \ > - /* Chop off the end of the file. \ > - */ \ > - if (ftruncate(fd, newsize)) { \ > - err("could not resize file"); \ > - goto warning; \ > - } \ > - \ > - return TRUE; \ > - \ > - warning: \ > - return err("ELF file may have been corrupted!"); \ > -} > - > - > -/* First elements of Elf32_Ehdr and Elf64_Ehdr are common. > - */ > -static int readelfheaderident(int fd, Elf32_Ehdr *ehdr) > -{ > - errno = 0; > - if (read(fd, ehdr, EI_NIDENT) != EI_NIDENT) > - return ferr("missing or incomplete ELF header."); > - > - /* Check the ELF signature. > - */ > - if (!(ehdr->e_ident[EI_MAG0] == ELFMAG0 && > - ehdr->e_ident[EI_MAG1] == ELFMAG1 && > - ehdr->e_ident[EI_MAG2] == ELFMAG2 && > - ehdr->e_ident[EI_MAG3] == ELFMAG3)) > - { > - err("missing ELF signature."); > - return -1; > - } > - > - /* Compare the file's class and endianness with the program's. > - */ > -#if __BYTE_ORDER == __LITTLE_ENDIAN > - if (ehdr->e_ident[EI_DATA] == ELFDATA2LSB) { > - do_reverse_endian = 0; > - } else if (ehdr->e_ident[EI_DATA] == ELFDATA2MSB) { > -/* fprintf(stderr, "ELF file has different endianness.\n"); */ > - do_reverse_endian = 1; > - } > -#elif __BYTE_ORDER == __BIG_ENDIAN > - if (ehdr->e_ident[EI_DATA] == ELFDATA2LSB) { > -/* fprintf(stderr, "ELF file has different endianness.\n"); */ > - do_reverse_endian = 1; > - } else if (ehdr->e_ident[EI_DATA] == ELFDATA2MSB) { > - do_reverse_endian = 0; > - } > -#else > -#error unkown endianness > -#endif > - else { > - err("Unsupported endianness"); > - return -1; > - } > - > - /* Check the target architecture. > - */ > -/* if (EGET(ehdr->e_machine) != ELF_ARCH) { */ > -/* /\* return err("ELF file created for different architecture."); *\/ > */ > -/* fprintf(stderr, "ELF file created for different architecture.\n"); > */ > -/* } */ > - return ehdr->e_ident[EI_CLASS]; > -} > - > - > -HEADER_FUNCTIONS(32) > - > -HEADER_FUNCTIONS(64) > - > -/* truncatezeros() examines the bytes at the end of the file's > - * size-to-be, and reduces the size to exclude any trailing zero > - * bytes. > - */ > -static int truncatezeros(int fd, unsigned long *newsize) > -{ > - unsigned char contents[1024]; > - unsigned long size, n; > - > - size = *newsize; > - do { > - n = sizeof contents; > - if (n > size) > - n = size; > - if (lseek(fd, size - n, SEEK_SET) == (off_t)-1) > - return ferr("cannot seek in file."); > - if (read(fd, contents, n) != (ssize_t)n) > - return ferr("cannot read file contents"); > - while (n && !contents[--n]) > - --size; > - } while (size && !n); > - > - /* Sanity check. > - */ > - if (!size) > - return err("ELF file is completely blank!"); > - > - *newsize = size; > - return TRUE; > -} > - > -/* main() loops over the cmdline arguments, leaving all the real work > - * to the other functions. > - */ > -int main(int argc, char *argv[]) > -{ > - int fd; > - union { > - Elf32_Ehdr ehdr32; > - Elf64_Ehdr ehdr64; > - } e; > - union { > - Elf32_Phdr *phdrs32; > - Elf64_Phdr *phdrs64; > - } p; > - unsigned long newsize; > - char **arg; > - int failures = 0; > - > - if (argc < 2 || argv[1][0] == '-') { > - printf("Usage: sstrip FILE...\n" > - "sstrip discards all nonessential bytes from an executable.\n\n" > - "Version 2.0-X Copyright (C) 2000,2001 Brian Raiter.\n" > - "Cross-devel hacks Copyright (C) 2004 Manuel Novoa III.\n" > - "This program is free software, licensed under the GNU\n" > - "General Public License. There is absolutely no warranty.\n"); > - return EXIT_SUCCESS; > - } > - > - progname = argv[0]; > - > - for (arg = argv + 1 ; *arg != NULL ; ++arg) { > - filename = *arg; > - > - fd = open(*arg, O_RDWR); > - if (fd < 0) { > - ferr("can't open"); > - ++failures; > - continue; > - } > - > - switch (readelfheaderident(fd, &e.ehdr32)) { > - case ELFCLASS32: > - if (!(readelfheader32(fd, &e.ehdr32) && > - readphdrtable32(fd, &e.ehdr32, &p.phdrs32) && > - getmemorysize32(&e.ehdr32, p.phdrs32, &newsize) && > - truncatezeros(fd, &newsize) && > - modifyheaders32(&e.ehdr32, p.phdrs32, newsize) && > - commitchanges32(fd, &e.ehdr32, p.phdrs32, newsize))) > - ++failures; > - break; > - case ELFCLASS64: > - if (!(readelfheader64(fd, &e.ehdr64) && > - readphdrtable64(fd, &e.ehdr64, &p.phdrs64) && > - getmemorysize64(&e.ehdr64, p.phdrs64, &newsize) && > - truncatezeros(fd, &newsize) && > - modifyheaders64(&e.ehdr64, p.phdrs64, newsize) && > - commitchanges64(fd, &e.ehdr64, p.phdrs64, newsize))) > - ++failures; > - break; > - default: > - ++failures; > - break; > - } > - close(fd); > - } > - > - return failures ? EXIT_FAILURE : EXIT_SUCCESS; > -} > -- > 2.29.2 > > > _______________________________________________ > openwrt-devel mailing list > openwrt-devel@lists.openwrt.org > https://lists.openwrt.org/mailman/listinfo/openwrt-devel _______________________________________________ openwrt-devel mailing list openwrt-devel@lists.openwrt.org https://lists.openwrt.org/mailman/listinfo/openwrt-devel
