usr.bin/kzip/kzip.c

   1 /*
   2  * ----------------------------------------------------------------------------
   3  * "THE BEER-WARE LICENSE" (Revision 42):
   4  * <phk@login.dknet.dk> wrote this file.  As long as you retain this notice you
   5  * can do whatever you want with this stuff. If we meet some day, and you think
   6  * this stuff is worth it, you can buy me a beer in return.   Poul-Henning Kamp
   7  * ----------------------------------------------------------------------------
   8  *
   9  * Copyright (C) 1993  Hannu Savolainen
  10  * Ported to 386bsd by Serge Vakulenko
  11  * based on tools/build.c by Linus Torvalds
  12  *
  13  * $FreeBSD: src/usr.bin/kzip/kzip.c,v 1.13.2.2 2000/07/20 10:35:20 kris Exp $
  14  */
  15
  16 #include <err.h>
  17 #include <stdio.h>
  18 #include <stdlib.h>
  19 #include <unistd.h>
  20 #include <sys/file.h>
  21 #include <sys/types.h>
  22 #include <sys/stat.h>
  23 #include <sys/param.h>
  24 #include <sys/wait.h>
  25 #include <a.out.h>
  26 #include <string.h>
  27
  28 /*
  29  * This is the limit because a kzip'ed kernel loads at 3Mb and
  30  * ends up at 1Mb
  31  */
  32 #define MAXIMAGE        (2*1024*1024)
  33
  34 static char string_names[] = {"_input_data\0_input_len\0"};
  35
  36 static struct nlist var_names[2] = {                    /* Symbol table */
  37         { { (char*)  4 }, N_EXT|N_TEXT, 0, 0, 0 },      /* _input_data  */
  38         { { (char*) 16 }, N_EXT|N_TEXT, 0, 0, 0 },      /* _input_len */
  39 };
  40
  41 static int
  42 extract(char *file)
  43 {
  44         int sz;
  45         char buf[BUFSIZ];
  46         struct exec hdr;
  47
  48         if (read(0, (char *)&hdr, sizeof(hdr)) != sizeof(hdr))
  49                 err(2, "%s", file);
  50         if (hdr.a_magic != ZMAGIC)
  51                 errx(2, "bad magic in file %s, probably not a kernel", file);
  52         if (lseek(0, N_TXTOFF(hdr), 0) < 0)
  53                 err(2, "%s", file);
  54
  55         sz = N_SYMOFF(hdr) - N_TXTOFF(hdr);
  56
  57         while (sz) {
  58                 size_t l;
  59                 ssize_t n;
  60
  61                 l = sz;
  62                 if (l > sizeof(buf))
  63                         l = sizeof(buf);
  64
  65                 n = read(0, buf, l);
  66                 if (n != l) {
  67                         if (n == -1)
  68                                 err(1, "%s", file);
  69                         else
  70                                 errx(1, "unexpected EOF");
  71                 }
  72
  73                 write(1, buf, l);
  74                 sz -= l;
  75         }
  76         exit(0);
  77 }
  78
  79 static int
  80 piggyback(char *file)
  81 {
  82         int n, len;
  83         struct exec hdr;                        /* object header */
  84         char image[MAXIMAGE];                   /* kernel image buffer */
  85
  86         len = 0;
  87         while ((n = read(0, &image[len], sizeof(image)-len+1)) > 0)
  88               len += n;
  89
  90         if (n < 0)
  91                 err(1, "stdin");
  92
  93         if (len >= sizeof(image))
  94                 errx(1, "input too large");
  95
  96         /*
  97          *      Output object header
  98          */
  99         memset(&hdr,0,sizeof hdr);
 100         hdr.a_magic = OMAGIC;
 101         hdr.a_text = len + sizeof(long);
 102         hdr.a_syms = sizeof(var_names);
 103         write(1, (char *)&hdr, sizeof(hdr));
 104
 105         /*
 106          *      Output text segment (compressed system & len)
 107          */
 108         write(1, image, len);
 109         write(1, (char *)&len, sizeof(len));
 110
 111         /*
 112          *      Output symbol table
 113          */
 114         var_names[1].n_value = len;
 115         write(1, (char *)&var_names, sizeof(var_names));
 116
 117         /*
 118          *      Output string table
 119          */
 120         len = sizeof(string_names) + sizeof(len);
 121         write(1, (char *)&len, sizeof(len));
 122         write(1, string_names, sizeof(string_names));
 123
 124         return (0);
 125 }
 126
 127 static void
 128 usage(void)
 129 {
 130         fprintf(stderr, "usage: kzip [-v] [ -l loadaddr] kernel\n");
 131         exit(1);
 132 }
 133
 134 int
 135 main(int argc, char **argv)
 136 {
 137         pid_t Pext, Pgzip, Ppiggy, Pld;
 138         int pipe1[2], pipe2[2];
 139         int status, fdi, fdo, fdn, c, verbose;
 140         int size;
 141         struct exec hdr;
 142         int zip_size, offset;
 143         struct stat st;
 144         u_long forceaddr = 0, entry;
 145         char *kernname;
 146         char obj[MAXPATHLEN + 1];
 147         char out[MAXPATHLEN + 1];
 148         char base[32];
 149
 150         while ((c = getopt(argc, argv, "l:v")) != -1) {
 151                 switch (c) {
 152                 case 'l':
 153                         forceaddr = strtoul(optarg, NULL, 0);
 154                         if (forceaddr == 0)
 155                                 errx(1, "invalid load address");
 156                         break;
 157                 case 'v':
 158                         verbose++;
 159                         break;
 160                 default:
 161                         usage();
 162                 }
 163         }
 164
 165         if ((argc - optind) != 1)
 166                 usage();
 167
 168         argc -= optind;
 169         argv += optind;
 170
 171         kernname = argv[0];
 172
 173         if (strlen(kernname) > MAXPATHLEN - 3)
 174                 errx(1, "%s: File name too long", kernname);
 175         strcpy(obj, kernname); strcat(obj,".o");
 176         strcpy(out, kernname); strcat(out,".kz");
 177
 178         fdi = open(kernname ,O_RDONLY);
 179         if(fdi<0) {
 180                 warn("%s", kernname);
 181                 return 2;
 182         }
 183
 184         /* figure out how big the uncompressed image will be */
 185         if (read(fdi, (char *)&hdr, sizeof(hdr)) != sizeof(hdr))
 186                 err(2, "%s", argv[1]);
 187
 188         size = hdr.a_text + hdr.a_data + hdr.a_bss;
 189         entry = hdr.a_entry & 0x00FFFFFF;
 190
 191         lseek(fdi, 0, SEEK_SET);
 192
 193         if (verbose) {
 194                 printf("real kernel start address will be: 0x%lx\n", entry);
 195                 printf("real kernel end   address will be: 0x%lx\n", entry+size);
 196         }
 197
 198
 199         fdo = open(obj,O_WRONLY|O_TRUNC|O_CREAT,0666);
 200         if(fdo<0) {
 201                 warn("%s", obj);
 202                 return 2;
 203         }
 204
 205         if (pipe(pipe1) < 0) { perror("pipe()"); return 1; }
 206
 207         if (pipe(pipe2) < 0) { perror("pipe()"); return 1; }
 208
 209         Pext = fork();
 210         if (Pext < 0) { perror("fork()"); return 1; }
 211         if (!Pext) {
 212                 dup2(fdi,0);
 213                 dup2(pipe1[1],1);
 214                 close(pipe1[0]); close(pipe1[1]);
 215                 close(pipe2[0]); close(pipe2[1]);
 216                 close(fdi); close(fdo);
 217                 extract(kernname);
 218                 exit(0);
 219         }
 220
 221         Pgzip = fork();
 222         if (Pgzip < 0) { perror("fork()"); return 1; }
 223         if (!Pgzip) {
 224                 dup2(pipe1[0],0);
 225                 dup2(pipe2[1],1);
 226                 close(pipe1[0]); close(pipe1[1]);
 227                 close(pipe2[0]); close(pipe2[1]);
 228                 close(fdi); close(fdo);
 229                 execlp("gzip", "gzip", "-9", "-n", NULL);
 230                 exit(0);
 231         }
 232
 233         Ppiggy = fork();
 234         if (Ppiggy < 0) { warn("fork()"); return 1; }
 235         if (!Ppiggy) {
 236                 dup2(pipe2[0],0);
 237                 dup2(fdo,1);
 238                 close(pipe1[0]); close(pipe1[1]);
 239                 close(pipe2[0]); close(pipe2[1]);
 240                 close(fdi); close(fdo);
 241                 piggyback(obj);
 242                 exit(0);
 243         }
 244
 245         close(pipe1[0]); close(pipe1[1]);
 246         close(pipe2[0]); close(pipe2[1]);
 247         close(fdi); close(fdo);
 248
 249         if (waitpid(Pext, &status,0) < 0)
 250                 { warn("waitpid(Pextract)"); return 1; }
 251
 252         if(status) {
 253                 warnx("extract returned %x",status);
 254                 return 3;
 255         }
 256
 257         if (waitpid(Pgzip, &status,0) < 0)
 258                 { perror("waitpid(Pgzip)"); return 1; }
 259
 260         if(status) {
 261                 warnx("gzip returned %x",status);
 262                 return 3;
 263         }
 264
 265         if (waitpid(Ppiggy, &status,0) < 0)
 266                 { warn("waitpid(Ppiggy)"); return 1; }
 267
 268         if(status) {
 269                 warnx("piggyback returned %x",status);
 270                 return 3;
 271         }
 272
 273         if (forceaddr)
 274                 offset = forceaddr;
 275         else {
 276                 /* a kludge to dynamically figure out where to start it */
 277                 if (stat(obj, &st) < 0) {
 278                         warn("cannot get size of compressed data");
 279                         return 3;
 280                 }
 281                 zip_size = (int)st.st_size;
 282                 offset = entry + size - zip_size + 0x8000; /* fudge factor */
 283         }
 284         sprintf(base, "0x%x", roundup(offset, 4096));
 285
 286         Pld = fork();
 287         if (Pld < 0) { warn("fork()"); return 1; }
 288         if (!Pld) {
 289                 execlp("ld",
 290                         "ld",
 291                         "-aout",
 292                         "-Bstatic",
 293                         "-Z",
 294                         "-T",
 295                         base,
 296                         "-o",
 297                         out,
 298                         "/usr/lib/aout/kzhead.o",
 299                         obj,
 300                         "/usr/lib/aout/kztail.o",
 301                         NULL);
 302                 exit(2);
 303         }
 304
 305         if (waitpid(Pld, &status,0) < 0)
 306                 { warn("waitpid(Pld)"); return 1; }
 307
 308         if(status) {
 309                 warnx("ld returned %x",status);
 310                 return 3;
 311         }
 312
 313         if (verbose) {
 314
 315                 fdn = open(obj ,O_RDONLY);
 316                 if(fdn<0) {
 317                         warn("%s", obj);
 318                         return 3;
 319                 }
 320
 321                 /* figure out how big the compressed image is */
 322                 if (read(fdn, (char *)&hdr, sizeof(hdr)) != sizeof(hdr)) {
 323                         warn("%s", obj);
 324                         return 3;
 325                 }
 326                 close(fdn);
 327
 328                 size = hdr.a_text + hdr.a_data + hdr.a_bss;
 329
 330                 printf("kzip data   start address will be: 0x%x\n",offset);
 331                 printf("kzip data   end   address will be: 0x%x\n",offset+size);
 332         }
 333
 334         unlink(obj);
 335         exit(0);
 336 }