kgzcmp.c revision 76224
1/* 2 * Copyright (c) 1999 Global Technology Associates, Inc. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 17 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS 18 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 19 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 20 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR 21 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 22 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE 23 * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, 24 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 * 26 * $FreeBSD: head/usr.sbin/kgzip/kgzcmp.c 76224 2001-05-02 23:56:21Z obrien $ 27 */ 28 29#include <sys/types.h> 30#include <sys/stat.h> 31#include <sys/wait.h> 32#include <machine/elf.h> 33 34#include <err.h> 35#include <fcntl.h> 36#include <stdio.h> 37#include <stdlib.h> 38#include <unistd.h> 39 40#include <a.out.h> 41 42#include "aouthdr.h" 43#include "elfhdr.h" 44#include "kgzip.h" 45 46static void mk_data(const struct iodesc *i, const struct iodesc *, 47 struct kgz_hdr *, size_t); 48static int ld_elf(const struct iodesc *, const struct iodesc *, 49 struct kgz_hdr *, const Elf32_Ehdr *); 50static int ld_aout(const struct iodesc *, const struct iodesc *, 51 struct kgz_hdr *, const struct exec *); 52 53/* 54 * Compress executable and output it in relocatable object format. 55 */ 56void 57kgzcmp(struct kgz_hdr *kh, const char *f1, const char *f2) 58{ 59 struct iodesc idi, ido; 60 61 if ((idi.fd = open(idi.fname = f1, O_RDONLY)) == -1) 62 err(1, "%s", idi.fname); 63 if ((ido.fd = open(ido.fname = f2, O_CREAT | O_TRUNC | O_WRONLY, 64 0666)) == -1) 65 err(1, "%s", ido.fname); 66 kh->ident[0] = KGZ_ID0; 67 kh->ident[1] = KGZ_ID1; 68 kh->ident[2] = KGZ_ID2; 69 kh->ident[3] = KGZ_ID3; 70 mk_data(&idi, &ido, kh, 71 (format == F_AOUT ? sizeof(struct kgz_aouthdr0) : 72 sizeof(struct kgz_elfhdr)) + 73 sizeof(struct kgz_hdr)); 74 kh->dload &= 0xffffff; 75 kh->entry &= 0xffffff; 76 if (format == F_AOUT) { 77 struct kgz_aouthdr0 ahdr0 = aouthdr0; 78 struct kgz_aouthdr1 ahdr1 = aouthdr1; 79 unsigned x = (sizeof(struct kgz_hdr) + kh->nsize) & (16 - 1); 80 if (x) { 81 x = 16 - x; 82 xzero(&ido, x); 83 } 84 xwrite(&ido, &ahdr1, sizeof(ahdr1)); 85 ahdr0.a.a_data += kh->nsize + x; 86 xseek(&ido, 0); 87 xwrite(&ido, &ahdr0, sizeof(ahdr0)); 88 } else { 89 struct kgz_elfhdr ehdr = elfhdr; 90 ehdr.st[KGZ_ST_KGZ_NDATA].st_size = kh->nsize; 91 ehdr.sh[KGZ_SH_DATA].sh_size += kh->nsize; 92 xseek(&ido, 0); 93 xwrite(&ido, &ehdr, sizeof(ehdr)); 94 } 95 xwrite(&ido, kh, sizeof(*kh)); 96 xclose(&ido); 97 xclose(&idi); 98} 99 100/* 101 * Make encoded (compressed) data. 102 */ 103static void 104mk_data(const struct iodesc * idi, const struct iodesc * ido, 105 struct kgz_hdr * kh, size_t off) 106{ 107 union { 108 struct exec ex; 109 Elf32_Ehdr ee; 110 } hdr; 111 struct stat sb; 112 struct iodesc idp; 113 int fd[2]; 114 pid_t pid; 115 size_t n; 116 int fmt, status, e; 117 118 n = xread(idi, &hdr, sizeof(hdr), 0); 119 fmt = 0; 120 if (n >= sizeof(hdr.ee) && IS_ELF(hdr.ee)) 121 fmt = F_ELF; 122 else if (n >= sizeof(hdr.ex) && N_GETMAGIC(hdr.ex) == ZMAGIC) 123 fmt = F_AOUT; 124 if (!fmt) 125 errx(1, "%s: Format not supported", idi->fname); 126 xseek(ido, off); 127 if (pipe(fd)) 128 err(1, NULL); 129 switch (pid = fork()) { 130 case -1: 131 err(1, NULL); 132 case 0: 133 close(fd[1]); 134 dup2(fd[0], STDIN_FILENO); 135 close(fd[0]); 136 close(idi->fd); 137 dup2(ido->fd, STDOUT_FILENO); 138 close(ido->fd); 139 execlp("gzip", "gzip", "-9", NULL); 140 warn(NULL); 141 _exit(1); 142 default: 143 close(fd[0]); 144 idp.fname = "(pipe)"; 145 idp.fd = fd[1]; 146 e = fmt == F_ELF ? ld_elf(idi, &idp, kh, &hdr.ee) : 147 fmt == F_AOUT ? ld_aout(idi, &idp, kh, &hdr.ex) : -1; 148 close(fd[1]); 149 if ((pid = waitpid(pid, &status, 0)) == -1) 150 err(1, NULL); 151 if (WIFSIGNALED(status) || WEXITSTATUS(status)) 152 exit(1); 153 } 154 if (e) 155 errx(1, "%s: Invalid format", idi->fname); 156 if (fstat(ido->fd, &sb)) 157 err(1, "%s", ido->fname); 158 kh->nsize = sb.st_size - off; 159} 160 161/* 162 * "Load" an ELF-format executable. 163 */ 164static int 165ld_elf(const struct iodesc * idi, const struct iodesc * ido, 166 struct kgz_hdr * kh, const Elf32_Ehdr * e) 167{ 168 Elf32_Phdr p; 169 size_t load, addr, n; 170 unsigned x, i; 171 172 load = addr = n = 0; 173 for (x = i = 0; i < e->e_phnum; i++) { 174 if (xread(idi, &p, sizeof(p), 175 e->e_phoff + i * e->e_phentsize) != e->e_phentsize) 176 return -1; 177 if (p.p_type != PT_LOAD) 178 continue; 179 if (!x) 180 load = addr = p.p_vaddr; 181 else { 182 if (p.p_vaddr < addr) 183 return -1; 184 n = p.p_vaddr - addr; 185 if (n) { 186 xzero(ido, n); 187 addr += n; 188 } 189 } 190 if (p.p_memsz < p.p_filesz) 191 return -1; 192 n = p.p_memsz - p.p_filesz; 193 xcopy(idi, ido, p.p_filesz, p.p_offset); 194 addr += p.p_filesz; 195 x++; 196 } 197 if (!x) 198 return -1; 199 kh->dload = load; 200 kh->dsize = addr - load; 201 kh->isize = kh->dsize + n; 202 kh->entry = e->e_entry; 203 return 0; 204} 205 206/* 207 * "Load" an a.out-format executable. 208 */ 209static int 210ld_aout(const struct iodesc * idi, const struct iodesc * ido, 211 struct kgz_hdr * kh, const struct exec * a) 212{ 213 size_t load, addr; 214 215 load = addr = N_TXTADDR(*a); 216 xcopy(idi, ido, a->a_text, N_TXTOFF(*a)); 217 addr += a->a_text; 218 if (N_DATADDR(*a) != addr) 219 return -1; 220 xcopy(idi, ido, a->a_data, N_DATOFF(*a)); 221 addr += a->a_data; 222 kh->dload = load; 223 kh->dsize = addr - load; 224 kh->isize = kh->dsize + a->a_bss; 225 kh->entry = a->a_entry; 226 return 0; 227} 228