IPXE/ipxe-3fe683e/src/arch/x86/core/runtime.c

   1 /*
   2  * Copyright (C) 2011 Michael Brown <mbrown@fensystems.co.uk>.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License as
   6  * published by the Free Software Foundation; either version 2 of the
   7  * License, or any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  17  * 02110-1301, USA.
  18  *
  19  * You can also choose to distribute this program under the terms of
  20  * the Unmodified Binary Distribution Licence (as given in the file
  21  * COPYING.UBDL), provided that you have satisfied its requirements.
  22  */
  23
  24 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
  25
  26 /** @file
  27  *
  28  * Command line and initrd passed to iPXE at runtime
  29  *
  30  */
  31
  32 #include <stddef.h>
  33 #include <stdint.h>
  34 #include <stdlib.h>
  35 #include <ctype.h>
  36 #include <errno.h>
  37 #include <assert.h>
  38 #include <ipxe/init.h>
  39 #include <ipxe/image.h>
  40 #include <ipxe/script.h>
  41 #include <ipxe/umalloc.h>
  42 #include <realmode.h>
  43 #include <ventoy.h>
  44
  45 /** Command line physical address
  46  *
  47  * This can be set by the prefix.
  48  */
  49 uint32_t __bss16 ( cmdline_phys );
  50 #define cmdline_phys __use_data16 ( cmdline_phys )
  51
  52 /** initrd physical address
  53  *
  54  * This can be set by the prefix.
  55  */
  56 uint32_t __bss16 ( initrd_phys );
  57 #define initrd_phys __use_data16 ( initrd_phys )
  58
  59 /** initrd length
  60  *
  61  * This can be set by the prefix.
  62  */
  63 uint32_t __bss16 ( initrd_len );
  64 #define initrd_len __use_data16 ( initrd_len )
  65
  66 /** Internal copy of the command line */
  67 static char *cmdline_copy;
  68
  69 /** Free command line image */
  70 static void cmdline_image_free ( struct refcnt *refcnt ) {
  71         struct image *image = container_of ( refcnt, struct image, refcnt );
  72
  73         DBGC ( image, "RUNTIME freeing command line\n" );
  74         free ( cmdline_copy );
  75 }
  76
  77 /** Embedded script representing the command line */
  78 static struct image cmdline_image = {
  79         .refcnt = REF_INIT ( cmdline_image_free ),
  80         .name = "<CMDLINE>",
  81         .type = &script_image_type,
  82 };
  83
  84 /** Colour for debug messages */
  85 #define colour &cmdline_image
  86
  87 /**
  88  * Strip unwanted cruft from command line
  89  *
  90  * @v cmdline           Command line
  91  * @v cruft             Initial substring of cruft to strip
  92  */
  93 static void cmdline_strip ( char *cmdline, const char *cruft ) {
  94         char *strip;
  95         char *strip_end;
  96
  97         /* Find unwanted cruft, if present */
  98         if ( ! ( strip = strstr ( cmdline, cruft ) ) )
  99                 return;
 100
 101         /* Strip unwanted cruft */
 102         strip_end = strchr ( strip, ' ' );
 103         if ( strip_end ) {
 104                 *strip_end = '\0';
 105                 DBGC ( colour, "RUNTIME stripping \"%s\"\n", strip );
 106                 strcpy ( strip, ( strip_end + 1 ) );
 107         } else {
 108                 DBGC ( colour, "RUNTIME stripping \"%s\"\n", strip );
 109                 *strip = '\0';
 110         }
 111 }
 112
 113 /**
 114  * Initialise command line
 115  *
 116  * @ret rc              Return status code
 117  */
 118 static int cmdline_init ( void ) {
 119         userptr_t cmdline_user;
 120         char *cmdline;
 121         size_t len;
 122         int rc;
 123
 124         /* Do nothing if no command line was specified */
 125         if ( ! cmdline_phys ) {
 126                 DBGC ( colour, "RUNTIME found no command line\n" );
 127                 return 0;
 128         }
 129         cmdline_user = phys_to_user ( cmdline_phys );
 130         len = ( strlen_user ( cmdline_user, 0 ) + 1 /* NUL */ );
 131
 132         /* Allocate and copy command line */
 133         cmdline_copy = malloc ( len );
 134         if ( ! cmdline_copy ) {
 135                 DBGC ( colour, "RUNTIME could not allocate %zd bytes for "
 136                        "command line\n", len );
 137                 rc = -ENOMEM;
 138                 goto err_alloc_cmdline_copy;
 139         }
 140         cmdline = cmdline_copy;
 141         copy_from_user ( cmdline, cmdline_user, 0, len );
 142         DBGC ( colour, "RUNTIME found command line \"%s\" at %08x\n",
 143                cmdline, cmdline_phys );
 144
 145         /* Mark command line as consumed */
 146         cmdline_phys = 0;
 147
 148         /* Strip unwanted cruft from the command line */
 149         cmdline_strip ( cmdline, "BOOT_IMAGE=" );
 150         cmdline_strip ( cmdline, "initrd=" );
 151         while ( isspace ( *cmdline ) )
 152                 cmdline++;
 153         DBGC ( colour, "RUNTIME using command line \"%s\"\n", cmdline );
 154
 155         /* Prepare and register image */
 156         cmdline_image.data = virt_to_user ( cmdline );
 157         cmdline_image.len = strlen ( cmdline );
 158         if ( cmdline_image.len ) {
 159                 if ( ( rc = register_image ( &cmdline_image ) ) != 0 ) {
 160                         DBGC ( colour, "RUNTIME could not register command "
 161                                "line: %s\n", strerror ( rc ) );
 162                         goto err_register_image;
 163                 }
 164         }
 165
 166         /* Drop our reference to the image */
 167         image_put ( &cmdline_image );
 168
 169         return 0;
 170
 171  err_register_image:
 172         image_put ( &cmdline_image );
 173  err_alloc_cmdline_copy:
 174         return rc;
 175 }
 176
 177 /**
 178  * Initialise initrd
 179  *
 180  * @ret rc              Return status code
 181  */
 182 static int initrd_init ( void ) {
 183         struct image *image;
 184         int rc;
 185
 186         /* Do nothing if no initrd was specified */
 187         if ( ! initrd_phys ) {
 188                 DBGC ( colour, "RUNTIME found no initrd\n" );
 189                 return 0;
 190         }
 191         if ( ! initrd_len ) {
 192                 DBGC ( colour, "RUNTIME found empty initrd\n" );
 193                 return 0;
 194         }
 195         DBGC ( colour, "RUNTIME found initrd at [%x,%x)\n",
 196                initrd_phys, ( initrd_phys + initrd_len ) );
 197
 198         /* Allocate image */
 199         image = alloc_image ( NULL );
 200         if ( ! image ) {
 201                 DBGC ( colour, "RUNTIME could not allocate image for "
 202                        "initrd\n" );
 203                 rc = -ENOMEM;
 204                 goto err_alloc_image;
 205         }
 206         if ( ( rc = image_set_name ( image, "<INITRD>" ) ) != 0 ) {
 207                 DBGC ( colour, "RUNTIME could not set image name: %s\n",
 208                        strerror ( rc ) );
 209                 goto err_set_name;
 210         }
 211
 212         /* Allocate and copy initrd content */
 213         image->data = umalloc ( initrd_len );
 214         if ( ! image->data ) {
 215                 DBGC ( colour, "RUNTIME could not allocate %d bytes for "
 216                        "initrd\n", initrd_len );
 217                 rc = -ENOMEM;
 218                 goto err_umalloc;
 219         }
 220         image->len = initrd_len;
 221         memcpy_user ( image->data, 0, phys_to_user ( initrd_phys ), 0,
 222                       initrd_len );
 223
 224     g_initrd_addr = (void *)image->data;
 225     g_initrd_len = image->len;
 226     g_cmdline_copy = cmdline_copy;
 227
 228
 229         /* Mark initrd as consumed */
 230         initrd_phys = 0;
 231
 232         /* Register image */
 233         if ( ( rc = register_image ( image ) ) != 0 ) {
 234                 DBGC ( colour, "RUNTIME could not register initrd: %s\n",
 235                        strerror ( rc ) );
 236                 goto err_register_image;
 237         }
 238
 239         /* Drop our reference to the image */
 240         image_put ( image );
 241
 242         return 0;
 243
 244  err_register_image:
 245  err_umalloc:
 246  err_set_name:
 247         image_put ( image );
 248  err_alloc_image:
 249         return rc;
 250 }
 251
 252 /**
 253  * Initialise command line and initrd
 254  *
 255  */
 256 static void runtime_init ( void ) {
 257         int rc;
 258
 259         /* Initialise command line */
 260         if ( ( rc = cmdline_init() ) != 0 ) {
 261                 /* No way to report failure */
 262                 return;
 263         }
 264
 265         /* Initialise initrd */
 266         if ( ( rc = initrd_init() ) != 0 ) {
 267                 /* No way to report failure */
 268                 return;
 269         }
 270 }
 271
 272 /** Command line and initrd initialisation function */
 273 struct startup_fn runtime_startup_fn __startup_fn ( STARTUP_NORMAL ) = {
 274         .name = "runtime",
 275         .startup = runtime_init,
 276 };