/* $NetBSD: elfstrip.c,v 1.5 1997/10/18 13:54:55 lukem Exp $ */ /* * Copyright (c) 1995 * Ted Lemon (hereinafter referred to as the author) * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /* elf2elf.c */ #include #include #include #include #include #include #include #include /*#include */ #include #include struct sect { unsigned long vaddr; unsigned long len; }; int elf32_strip __P((const char *)); int main __P((int argc, char *argv[])); int phcmp __P((const void *, const void *)); void usage __P((void)); void *saveRead(int file, off_t offset, int len, char *name); void placeWrite(int file, off_t offset, int len, char *name, void *data); extern int errno; int xflag = 0; int main(argc, argv) int argc; char *argv[]; { int ch; while ((ch = getopt(argc, argv, "dx")) != -1) switch (ch) { case 'x': xflag = 1; /* FALLTHROUGH */ case 'd': #ifdef notyet sfcn = s_stab; #endif break; case '?': default: usage(); } argc -= optind; argv += optind; /* Check args... */ if (argc < 1) { usage(); } while (argc > 0) { elf32_strip(argv[0]); argc--; argv++; } return (0); } int elf32_strip(filename) const char *filename; { Elf32_Ehdr ex; Elf32_Phdr *ph; int i; int infile; unsigned long lastp; Elf32_Phdr **indt; void *segment; if ((infile = open(filename, O_RDWR)) < 0) { fprintf(stderr, "Can't open %s for read/write: %s\n", filename, strerror(errno)); exit(1); } /* Read the header, which is at the beginning of the file... */ /* ** printf("elf header from file 0 size %x\n", sizeof ex); */ i = read(infile, &ex, sizeof ex); if (i != sizeof ex) { fprintf(stderr, "ex: %s: %s.\n", filename, i ? strerror(errno) : "End of file reached"); exit(1); } if (strncmp(ex.e_ident, Elf32_e_ident, sizeof(ex.e_ident)) != 0) { fprintf(stderr, "strip: %s not ELF format\n", filename); return (0); } /* Devalidate section headers */ ex.e_shoff = 0; ex.e_shnum = 0; ex.e_shentsize = 0; ex.e_shstrndx = 0; placeWrite(infile, 0, sizeof ex, "ex", &ex); /* Read the program headers... */ /* ** printf("program headers from file %x size %x\n", ** ex.phoff, ex.phcount * sizeof (Elf32_Phdr)); */ lastp = ex.e_phoff + ex.e_phnum * sizeof(Elf32_Phdr); ph = (Elf32_Phdr *) saveRead(infile, ex.e_phoff, ex.e_phnum * sizeof(Elf32_Phdr), "ph"); indt = (Elf32_Phdr **) malloc(ex.e_phnum * sizeof(Elf32_Phdr **)); for (i = 0; i < ex.e_phnum; i++) { indt[i] = ph + i; } qsort(indt, ex.e_phnum, sizeof(Elf32_Phdr **), phcmp); for (i = 0; i < ex.e_phnum; i++) { Elf32_Phdr *php = indt[i]; /* Section types we can ignore... */ if (php->p_type == Elf_pt_null || php->p_type == Elf_pt_note || php->p_type == Elf_pt_phdr || php->p_type == Elf_pt_mips_reginfo) { printf("segment type %ld ignored file %lx size %lx\n", (long)php->p_type, (long)php->p_offset, (long)php->p_filesz); continue; } /* Section types we can't handle... */ else if (php->p_type != Elf_pt_load) { fprintf(stderr, "Program header %d type %ld can't be converted.\n", php - ph, (long)php->p_type); exit(1); } /* ** printf("segment %d load file %x size %x end %x\n", ** php-ph, ** php->p_offset, php->p_filesz, php->p_offset + php->p_filesz); */ if ((php->p_offset - lastp) > 0x2000) { int pg; pg = ((php->p_offset - lastp) / 0x2000); pg *= 0x2000; segment = saveRead(infile, php->p_offset, php->p_filesz, "segment"); php->p_offset -= pg; placeWrite(infile, php->p_offset, php->p_filesz, "segment", segment); /* ** printf("Move segment %d shift %x to %x\n", ** php-ph, pg, php->p_offset); */ } lastp = php->p_offset + php->p_filesz; } placeWrite(infile, ex.e_phoff, ex.e_phnum * sizeof(Elf32_Phdr), "ph", ph); ftruncate(infile, lastp); /* Looks like we won... */ exit(0); } int phcmp(vh1, vh2) const void *vh1, *vh2; { Elf32_Phdr **h1, **h2; h1 = (Elf32_Phdr **) vh1; h2 = (Elf32_Phdr **) vh2; if ((*h1)->p_offset > (*h2)->p_offset) return 1; else if ((*h1)->p_offset < (*h2)->p_offset) return -1; else return 0; } void * saveRead(int file, off_t offset, int len, char *name) { void *tmp; int count; off_t off; if ((off = lseek(file, offset, SEEK_SET)) < 0) { fprintf(stderr, "%s: fseek: %s\n", name, strerror(errno)); exit(1); } if (!(tmp = malloc(len))) { fprintf(stderr, "%s: Can't allocate %d bytes.\n", name, len); exit(1); } count = read(file, tmp, len); if (count != len) { fprintf(stderr, "%s: read: %s.\n", name, count ? strerror(errno) : "End of file reached"); exit(1); } return tmp; } void placeWrite(int file, off_t offset, int len, char *name, void *data) { int count; off_t off; if ((off = lseek(file, offset, SEEK_SET)) < 0) { fprintf(stderr, "%s: lseek: %s\n", name, strerror(errno)); exit(1); } count = write(file, data, len); if (count != len) { fprintf(stderr, "%s: write: %s.\n", name, strerror(errno)); exit(1); } } void usage() { (void) fprintf(stderr, "usage: strip [-dx] file ...\n"); exit(1); }