src/usr/pxemenu.c

   1 /*
   2  * Copyright (C) 2009 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., 675 Mass Ave, Cambridge, MA 02139, USA.
  17  */
  18
  19 FILE_LICENCE ( GPL2_OR_LATER );
  20
  21 #include <stdint.h>
  22 #include <stdlib.h>
  23 #include <stdio.h>
  24 #include <string.h>
  25 #include <errno.h>
  26 #include <ctype.h>
  27 #include <byteswap.h>
  28 #include <curses.h>
  29 #include <console.h>
  30 #include <gpxe/dhcp.h>
  31 #include <gpxe/keys.h>
  32 #include <gpxe/timer.h>
  33 #include <gpxe/process.h>
  34 #include <usr/dhcpmgmt.h>
  35 #include <usr/autoboot.h>
  36
  37 /** @file
  38  *
  39  * PXE Boot Menus
  40  *
  41  */
  42
  43 /* Colour pairs */
  44 #define CPAIR_NORMAL    1
  45 #define CPAIR_SELECT    2
  46
  47 /** A PXE boot menu item */
  48 struct pxe_menu_item {
  49         /** Boot Server type */
  50         unsigned int type;
  51         /** Description */
  52         char *desc;
  53 };
  54
  55 /**
  56  * A PXE boot menu
  57  *
  58  * This structure encapsulates the menu information provided via DHCP
  59  * options.
  60  */
  61 struct pxe_menu {
  62         /** Prompt string (optional) */
  63         const char *prompt;
  64         /** Timeout (in seconds)
  65          *
  66          * Negative indicates no timeout (i.e. wait indefinitely)
  67          */
  68         int timeout;
  69         /** Number of menu items */
  70         unsigned int num_items;
  71         /** Selected menu item */
  72         unsigned int selection;
  73         /** Menu items */
  74         struct pxe_menu_item items[0];
  75 };
  76
  77 /**
  78  * Parse and allocate PXE boot menu
  79  *
  80  * @v menu              PXE boot menu to fill in
  81  * @ret rc              Return status code
  82  *
  83  * It is the callers responsibility to eventually free the allocated
  84  * boot menu.
  85  */
  86 static int pxe_menu_parse ( struct pxe_menu **menu ) {
  87         struct setting pxe_boot_menu_prompt_setting =
  88                 { .tag = DHCP_PXE_BOOT_MENU_PROMPT };
  89         struct setting pxe_boot_menu_setting =
  90                 { .tag = DHCP_PXE_BOOT_MENU };
  91         uint8_t raw_menu[256];
  92         int raw_prompt_len;
  93         int raw_menu_len;
  94         struct dhcp_pxe_boot_menu *raw_menu_item;
  95         struct dhcp_pxe_boot_menu_prompt *raw_menu_prompt;
  96         void *raw_menu_end;
  97         unsigned int num_menu_items;
  98         unsigned int i;
  99         int rc;
 100
 101         /* Fetch raw menu */
 102         memset ( raw_menu, 0, sizeof ( raw_menu ) );
 103         if ( ( raw_menu_len = fetch_setting ( NULL, &pxe_boot_menu_setting,
 104                                               raw_menu,
 105                                               sizeof ( raw_menu ) ) ) < 0 ) {
 106                 rc = raw_menu_len;
 107                 DBG ( "Could not retrieve raw PXE boot menu: %s\n",
 108                       strerror ( rc ) );
 109                 return rc;
 110         }
 111         if ( raw_menu_len >= ( int ) sizeof ( raw_menu ) ) {
 112                 DBG ( "Raw PXE boot menu too large for buffer\n" );
 113                 return -ENOSPC;
 114         }
 115         raw_menu_end = ( raw_menu + raw_menu_len );
 116
 117         /* Fetch raw prompt length */
 118         raw_prompt_len = fetch_setting_len ( NULL,
 119                                              &pxe_boot_menu_prompt_setting );
 120         if ( raw_prompt_len < 0 )
 121                 raw_prompt_len = 0;
 122
 123         /* Count menu items */
 124         num_menu_items = 0;
 125         raw_menu_item = ( ( void * ) raw_menu );
 126         while ( 1 ) {
 127                 if ( ( ( ( void * ) raw_menu_item ) +
 128                        sizeof ( *raw_menu_item ) ) > raw_menu_end )
 129                         break;
 130                 if ( ( ( ( void * ) raw_menu_item ) +
 131                        sizeof ( *raw_menu_item ) +
 132                        raw_menu_item->desc_len ) > raw_menu_end )
 133                         break;
 134                 num_menu_items++;
 135                 raw_menu_item = ( ( ( void * ) raw_menu_item ) +
 136                                   sizeof ( *raw_menu_item ) +
 137                                   raw_menu_item->desc_len );
 138         }
 139
 140         /* Allocate space for parsed menu */
 141         *menu = zalloc ( sizeof ( **menu ) +
 142                          ( num_menu_items * sizeof ( (*menu)->items[0] ) ) +
 143                          raw_menu_len + 1 /* NUL */ +
 144                          raw_prompt_len + 1 /* NUL */ );
 145         if ( ! *menu ) {
 146                 DBG ( "Could not allocate PXE boot menu\n" );
 147                 return -ENOMEM;
 148         }
 149
 150         /* Fill in parsed menu */
 151         (*menu)->num_items = num_menu_items;
 152         raw_menu_item = ( ( ( void * ) (*menu) ) + sizeof ( **menu ) +
 153                           ( num_menu_items * sizeof ( (*menu)->items[0] ) ) );
 154         memcpy ( raw_menu_item, raw_menu, raw_menu_len );
 155         for ( i = 0 ; i < num_menu_items ; i++ ) {
 156                 (*menu)->items[i].type = le16_to_cpu ( raw_menu_item->type );
 157                 (*menu)->items[i].desc = raw_menu_item->desc;
 158                 /* Set type to 0; this ensures that the description
 159                  * for the previous menu item is NUL-terminated.
 160                  * (Final item is NUL-terminated anyway.)
 161                  */
 162                 raw_menu_item->type = 0;
 163                 raw_menu_item = ( ( ( void * ) raw_menu_item ) +
 164                                   sizeof ( *raw_menu_item ) +
 165                                   raw_menu_item->desc_len );
 166         }
 167         if ( raw_prompt_len ) {
 168                 raw_menu_prompt = ( ( ( void * ) raw_menu_item ) +
 169                                     1 /* NUL */ );
 170                 fetch_setting ( NULL, &pxe_boot_menu_prompt_setting,
 171                                 raw_menu_prompt, raw_prompt_len );
 172                 (*menu)->timeout =
 173                         ( ( raw_menu_prompt->timeout == 0xff ) ?
 174                           -1 : raw_menu_prompt->timeout );
 175                 (*menu)->prompt = raw_menu_prompt->prompt;
 176         } else {
 177                 (*menu)->timeout = -1;
 178         }
 179
 180         return 0;
 181 }
 182
 183 /**
 184  * Draw PXE boot menu item
 185  *
 186  * @v menu              PXE boot menu
 187  * @v index             Index of item to draw
 188  * @v selected          Item is selected
 189  */
 190 static void pxe_menu_draw_item ( struct pxe_menu *menu,
 191                                  unsigned int index, int selected ) {
 192         char buf[COLS+1];
 193         size_t len;
 194         unsigned int row;
 195
 196         /* Prepare space-padded row content */
 197         len = snprintf ( buf, sizeof ( buf ), " %c. %s",
 198                          ( 'A' + index ), menu->items[index].desc );
 199         while ( len < ( sizeof ( buf ) - 1 ) )
 200                 buf[len++] = ' ';
 201         buf[ sizeof ( buf ) - 1 ] = '\0';
 202
 203         /* Draw row */
 204         row = ( LINES - menu->num_items + index );
 205         color_set ( ( selected ? CPAIR_SELECT : CPAIR_NORMAL ), NULL );
 206         mvprintw ( row, 0, "%s", buf );
 207         move ( row, 1 );
 208 }
 209
 210 /**
 211  * Make selection from PXE boot menu
 212  *
 213  * @v menu              PXE boot menu
 214  * @ret rc              Return status code
 215  */
 216 static int pxe_menu_select ( struct pxe_menu *menu ) {
 217         int key;
 218         unsigned int key_selection;
 219         unsigned int i;
 220         int rc = 0;
 221
 222         /* Initialise UI */
 223         initscr();
 224         start_color();
 225         init_pair ( CPAIR_NORMAL, COLOR_WHITE, COLOR_BLACK );
 226         init_pair ( CPAIR_SELECT, COLOR_BLACK, COLOR_WHITE );
 227         color_set ( CPAIR_NORMAL, NULL );
 228
 229         /* Draw initial menu */
 230         for ( i = 0 ; i < menu->num_items ; i++ )
 231                 printf ( "\n" );
 232         for ( i = 0 ; i < menu->num_items ; i++ )
 233                 pxe_menu_draw_item ( menu, ( menu->num_items - i - 1 ), 0 );
 234
 235         while ( 1 ) {
 236
 237                 /* Highlight currently selected item */
 238                 pxe_menu_draw_item ( menu, menu->selection, 1 );
 239
 240                 /* Wait for keyboard input */
 241                 while ( ! iskey() )
 242                         step();
 243                 key = getkey();
 244
 245                 /* Unhighlight currently selected item */
 246                 pxe_menu_draw_item ( menu, menu->selection, 0 );
 247
 248                 /* Act upon key */
 249                 if ( ( key == CR ) || ( key == LF ) ) {
 250                         pxe_menu_draw_item ( menu, menu->selection, 1 );
 251                         break;
 252                 } else if ( ( key == CTRL_C ) || ( key == ESC ) ) {
 253                         rc = -ECANCELED;
 254                         break;
 255                 } else if ( key == KEY_UP ) {
 256                         if ( menu->selection > 0 )
 257                                 menu->selection--;
 258                 } else if ( key == KEY_DOWN ) {
 259                         if ( menu->selection < ( menu->num_items - 1 ) )
 260                                 menu->selection++;
 261                 } else if ( ( key < KEY_MIN ) &&
 262                             ( ( key_selection = ( toupper ( key ) - 'A' ) )
 263                               < menu->num_items ) ) {
 264                         menu->selection = key_selection;
 265                         pxe_menu_draw_item ( menu, menu->selection, 1 );
 266                         break;
 267                 }
 268         }
 269
 270         /* Shut down UI */
 271         endwin();
 272
 273         return rc;
 274 }
 275
 276 /**
 277  * Prompt for (and make selection from) PXE boot menu
 278  *
 279  * @v menu              PXE boot menu
 280  * @ret rc              Return status code
 281  */
 282 static int pxe_menu_prompt_and_select ( struct pxe_menu *menu ) {
 283         unsigned long start = currticks();
 284         unsigned long now;
 285         unsigned long elapsed;
 286         size_t len = 0;
 287         int key;
 288         int rc = 0;
 289
 290         /* Display menu immediately, if specified to do so */
 291         if ( menu->timeout < 0 ) {
 292                 if ( menu->prompt )
 293                         printf ( "%s\n", menu->prompt );
 294                 return pxe_menu_select ( menu );
 295         }
 296
 297         /* Display prompt, if specified */
 298         if ( menu->prompt )
 299                 printf ( "%s", menu->prompt );
 300
 301         /* Wait for timeout, if specified */
 302         while ( menu->timeout > 0 ) {
 303                 if ( ! len )
 304                         len = printf ( " (%d)", menu->timeout );
 305                 if ( iskey() ) {
 306                         key = getkey();
 307                         if ( key == KEY_F8 ) {
 308                                 /* Display menu */
 309                                 printf ( "\n" );
 310                                 return pxe_menu_select ( menu );
 311                         } else if ( ( key == CTRL_C ) || ( key == ESC ) ) {
 312                                 /* Abort */
 313                                 rc = -ECANCELED;
 314                                 break;
 315                         } else {
 316                                 /* Stop waiting */
 317                                 break;
 318                         }
 319                 }
 320                 now = currticks();
 321                 elapsed = ( now - start );
 322                 if ( elapsed >= TICKS_PER_SEC ) {
 323                         menu->timeout -= 1;
 324                         do {
 325                                 printf ( "\b \b" );
 326                         } while ( --len );
 327                         start = now;
 328                 }
 329         }
 330
 331         /* Return with default option selected */
 332         printf ( "\n" );
 333         return rc;
 334 }
 335
 336 /**
 337  * Boot using PXE boot menu
 338  *
 339  * @ret rc              Return status code
 340  *
 341  * Note that a success return status indicates that a PXE boot menu
 342  * item has been selected, and that the DHCP session should perform a
 343  * boot server request/ack.
 344  */
 345 int pxe_menu_boot ( struct net_device *netdev ) {
 346         struct pxe_menu *menu;
 347         unsigned int pxe_type;
 348         struct settings *pxebs_settings;
 349         struct in_addr next_server;
 350         char filename[256];
 351         int rc;
 352
 353         /* Parse and allocate boot menu */
 354         if ( ( rc = pxe_menu_parse ( &menu ) ) != 0 )
 355                 return rc;
 356
 357         /* Make selection from boot menu */
 358         if ( ( rc = pxe_menu_prompt_and_select ( menu ) ) != 0 ) {
 359                 free ( menu );
 360                 return rc;
 361         }
 362         pxe_type = menu->items[menu->selection].type;
 363
 364         /* Free boot menu */
 365         free ( menu );
 366
 367         /* Return immediately if local boot selected */
 368         if ( ! pxe_type )
 369                 return 0;
 370
 371         /* Attempt PXE Boot Server Discovery */
 372         if ( ( rc = pxebs ( netdev, pxe_type ) ) != 0 )
 373                 return rc;
 374
 375         /* Attempt boot */
 376         pxebs_settings = find_settings ( PXEBS_SETTINGS_NAME );
 377         assert ( pxebs_settings );
 378         fetch_ipv4_setting ( pxebs_settings, &next_server_setting,
 379                              &next_server );
 380         fetch_string_setting ( pxebs_settings, &filename_setting,
 381                                filename, sizeof ( filename ) );
 382         return boot_next_server_and_filename ( next_server, filename );
 383 }