com32/modules/gpxecmd.c

   1 /* ----------------------------------------------------------------------- *
   2  *
   3  *   Copyright 2008 H. Peter Anvin - All Rights Reserved
   4  *
   5  *   This program is free software; you can redistribute it and/or modify
   6  *   it under the terms of the GNU General Public License as published by
   7  *   the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
   8  *   Boston MA 02110-1301, USA; either version 2 of the License, or
   9  *   (at your option) any later version; incorporated herein by reference.
  10  *
  11  * ----------------------------------------------------------------------- */
  12
  13 /*
  14  * gpxecmd.c
  15  *
  16  * Invoke an arbitrary gPXE command, if available.
  17  */
  18
  19 #include <alloca.h>
  20 #include <inttypes.h>
  21 #include <stdio.h>
  22 #include <console.h>
  23 #include <com32.h>
  24 #include <string.h>
  25 #include <sys/gpxe.h>
  26
  27 struct segoff16 {
  28     uint16_t offs, seg;
  29 };
  30
  31 struct s_PXENV_FILE_EXEC {
  32     uint16_t Status;
  33     struct segoff16 Command;
  34 };
  35
  36 static void gpxecmd(const char **args)
  37 {
  38     char *q;
  39     struct s_PXENV_FILE_EXEC *fx;
  40     com32sys_t reg;
  41
  42     memset(&reg, 0, sizeof reg);
  43
  44     fx = __com32.cs_bounce;
  45     q = (char *)(fx + 1);
  46
  47     fx->Status = 1;
  48     fx->Command.offs = OFFS(q);
  49     fx->Command.seg = SEG(q);
  50
  51     while (*args) {
  52         q = stpcpy(q, *args);
  53         *q++ = ' ';
  54         args++;
  55     }
  56     *--q = '\0';
  57
  58     memset(&reg, 0, sizeof reg);
  59     reg.eax.w[0] = 0x0009;
  60     reg.ebx.w[0] = 0x00e5;      /* PXENV_FILE_EXEC */
  61     reg.edi.w[0] = OFFS(fx);
  62     reg.es = SEG(fx);
  63
  64     __intcall(0x22, &reg, &reg);
  65
  66     /* This should not return... */
  67 }
  68
  69 int main(int argc, const char *argv[])
  70 {
  71     openconsole(&dev_null_r, &dev_stdcon_w);
  72
  73     if (argc < 2) {
  74         printf("Usage: gpxecmd command...\n");
  75         return 1;
  76     }
  77
  78     if (!is_gpxe()) {
  79         printf("gpxecmd: gPXE API not detected\n");
  80         return 1;
  81     }
  82
  83     gpxecmd(argv + 1);
  84
  85     return 0;
  86 }