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Diffstat (limited to 'src/arch/i386/interface/syslinux/comboot_call.c')
-rw-r--r--src/arch/i386/interface/syslinux/comboot_call.c598
1 files changed, 598 insertions, 0 deletions
diff --git a/src/arch/i386/interface/syslinux/comboot_call.c b/src/arch/i386/interface/syslinux/comboot_call.c
new file mode 100644
index 00000000..5a400ede
--- /dev/null
+++ b/src/arch/i386/interface/syslinux/comboot_call.c
@@ -0,0 +1,598 @@
+/*
+ * Copyright (C) 2008 Daniel Verkamp <daniel@drv.nu>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+/**
+ * @file SYSLINUX COMBOOT API
+ *
+ */
+
+#include <errno.h>
+#include <realmode.h>
+#include <biosint.h>
+#include <console.h>
+#include <stdlib.h>
+#include <comboot.h>
+#include <bzimage.h>
+#include <pxe_call.h>
+#include <setjmp.h>
+#include <string.h>
+#include <gpxe/posix_io.h>
+#include <gpxe/process.h>
+#include <gpxe/serial.h>
+#include <gpxe/init.h>
+
+/** The "SYSLINUX" version string */
+static char __data16_array ( syslinux_version, [] ) = "gPXE " VERSION;
+#define syslinux_version __use_data16 ( syslinux_version )
+
+/** The "SYSLINUX" copyright string */
+static char __data16_array ( syslinux_copyright, [] ) = "http://etherboot.org";
+#define syslinux_copyright __use_data16 ( syslinux_copyright )
+
+static char __data16_array ( syslinux_configuration_file, [] ) = "";
+#define syslinux_configuration_file __use_data16 ( syslinux_configuration_file )
+
+/** Feature flags */
+static uint8_t __data16 ( comboot_feature_flags ) = COMBOOT_FEATURE_IDLE_LOOP;
+#define comboot_feature_flags __use_data16 ( comboot_feature_flags )
+
+static struct segoff __text16 ( int20_vector );
+#define int20_vector __use_text16 ( int20_vector )
+
+static struct segoff __text16 ( int21_vector );
+#define int21_vector __use_text16 ( int21_vector )
+
+static struct segoff __text16 ( int22_vector );
+#define int22_vector __use_text16 ( int22_vector )
+
+extern void int20_wrapper ( void );
+extern void int21_wrapper ( void );
+extern void int22_wrapper ( void );
+
+/* setjmp/longjmp context buffer used to return after loading an image */
+jmp_buf comboot_return;
+
+/* Command line to execute when returning via comboot_return
+ * with COMBOOT_RETURN_RUN_KERNEL
+ */
+char *comboot_kernel_cmdline;
+
+/* Mode flags set by INT 22h AX=0017h */
+static uint16_t comboot_graphics_mode = 0;
+
+
+/**
+ * Print a string with a particular terminator
+ */
+static void print_user_string ( unsigned int segment, unsigned int offset, char terminator ) {
+ int i = 0;
+ char c;
+ userptr_t str = real_to_user ( segment, offset );
+ for ( ; ; ) {
+ copy_from_user ( &c, str, i, 1 );
+ if ( c == terminator ) break;
+ putchar ( c );
+ i++;
+ }
+}
+
+
+/**
+ * Perform a series of memory copies from a list in low memory
+ */
+static void shuffle ( unsigned int list_segment, unsigned int list_offset, unsigned int count )
+{
+ comboot_shuffle_descriptor shuf[COMBOOT_MAX_SHUFFLE_DESCRIPTORS];
+ unsigned int i;
+
+ /* Copy shuffle descriptor list so it doesn't get overwritten */
+ copy_from_user ( shuf, real_to_user ( list_segment, list_offset ), 0,
+ count * sizeof( comboot_shuffle_descriptor ) );
+
+ /* Do the copies */
+ for ( i = 0; i < count; i++ ) {
+ userptr_t src_u = phys_to_user ( shuf[ i ].src );
+ userptr_t dest_u = phys_to_user ( shuf[ i ].dest );
+
+ if ( shuf[ i ].src == 0xFFFFFFFF ) {
+ /* Fill with 0 instead of copying */
+ memset_user ( dest_u, 0, 0, shuf[ i ].len );
+ } else if ( shuf[ i ].dest == 0xFFFFFFFF ) {
+ /* Copy new list of descriptors */
+ count = shuf[ i ].len / sizeof( comboot_shuffle_descriptor );
+ assert ( count <= COMBOOT_MAX_SHUFFLE_DESCRIPTORS );
+ copy_from_user ( shuf, src_u, 0, shuf[ i ].len );
+ i = -1;
+ } else {
+ /* Regular copy */
+ memmove_user ( dest_u, 0, src_u, 0, shuf[ i ].len );
+ }
+ }
+}
+
+
+/**
+ * Set default text mode
+ */
+void comboot_force_text_mode ( void ) {
+ if ( comboot_graphics_mode & COMBOOT_VIDEO_VESA ) {
+ /* Set VGA mode 3 via VESA VBE mode set */
+ __asm__ __volatile__ (
+ REAL_CODE (
+ "mov $0x4F02, %%ax\n\t"
+ "mov $0x03, %%bx\n\t"
+ "int $0x10\n\t"
+ )
+ : : );
+ } else if ( comboot_graphics_mode & COMBOOT_VIDEO_GRAPHICS ) {
+ /* Set VGA mode 3 via standard VGA mode set */
+ __asm__ __volatile__ (
+ REAL_CODE (
+ "mov $0x03, %%ax\n\t"
+ "int $0x10\n\t"
+ )
+ : : );
+ }
+
+ comboot_graphics_mode = 0;
+}
+
+
+/**
+ * Run the kernel specified in comboot_kernel_cmdline
+ */
+void comboot_run_kernel ( )
+{
+ char *initrd;
+
+ comboot_force_text_mode ( );
+
+ DBG ( "COMBOOT: executing image '%s'\n", comboot_kernel_cmdline );
+
+ /* Find initrd= parameter, if any */
+ if ( ( initrd = strstr ( comboot_kernel_cmdline, "initrd=" ) ) ) {
+ char old_char = '\0';
+ char *initrd_end = strchr( initrd, ' ' );
+
+ /* Replace space after end of parameter
+ * with a nul terminator if this is not
+ * the last parameter
+ */
+ if ( initrd_end ) {
+ old_char = *initrd_end;
+ *initrd_end = '\0';
+ }
+
+ /* Replace = with space to get 'initrd filename'
+ * command suitable for system()
+ */
+ initrd[6] = ' ';
+
+ DBG( "COMBOOT: loading initrd '%s'\n", initrd );
+
+ system ( initrd );
+
+ /* Restore space after parameter */
+ if ( initrd_end ) {
+ *initrd_end = old_char;
+ }
+
+ /* Restore = */
+ initrd[6] = '=';
+ }
+
+ /* Load kernel */
+ DBG ( "COMBOOT: loading kernel '%s'\n", comboot_kernel_cmdline );
+ system ( comboot_kernel_cmdline );
+
+ free ( comboot_kernel_cmdline );
+
+ /* Boot */
+ system ( "boot" );
+
+ DBG ( "COMBOOT: back from executing command\n" );
+}
+
+
+/**
+ * Terminate program interrupt handler
+ */
+static __cdecl void int20 ( struct i386_all_regs *ix86 __unused ) {
+ longjmp ( comboot_return, COMBOOT_RETURN_EXIT );
+}
+
+
+/**
+ * DOS-compatible API
+ */
+static __cdecl void int21 ( struct i386_all_regs *ix86 ) {
+ ix86->flags |= CF;
+
+ switch ( ix86->regs.ah ) {
+ case 0x00:
+ case 0x4C: /* Terminate program */
+ longjmp ( comboot_return, COMBOOT_RETURN_EXIT );
+ break;
+
+ case 0x01: /* Get Key with Echo */
+ case 0x08: /* Get Key without Echo */
+ /* TODO: handle extended characters? */
+ ix86->regs.al = getchar( );
+
+ /* Enter */
+ if ( ix86->regs.al == 0x0A )
+ ix86->regs.al = 0x0D;
+
+ if ( ix86->regs.ah == 0x01 )
+ putchar ( ix86->regs.al );
+
+ ix86->flags &= ~CF;
+ break;
+
+ case 0x02: /* Write Character */
+ putchar ( ix86->regs.dl );
+ ix86->flags &= ~CF;
+ break;
+
+ case 0x04: /* Write Character to Serial Port */
+ serial_putc ( ix86->regs.dl );
+ ix86->flags &= ~CF;
+ break;
+
+ case 0x09: /* Write DOS String to Console */
+ print_user_string ( ix86->segs.ds, ix86->regs.dx, '$' );
+ ix86->flags &= ~CF;
+ break;
+
+ case 0x0B: /* Check Keyboard */
+ if ( iskey() )
+ ix86->regs.al = 0xFF;
+ else
+ ix86->regs.al = 0x00;
+
+ ix86->flags &= ~CF;
+ break;
+
+ case 0x30: /* Check DOS Version */
+ /* Bottom halves all 0; top halves spell "SYSLINUX" */
+ ix86->regs.eax = 0x59530000;
+ ix86->regs.ebx = 0x4C530000;
+ ix86->regs.ecx = 0x4E490000;
+ ix86->regs.edx = 0x58550000;
+ ix86->flags &= ~CF;
+ break;
+
+ default:
+ DBG ( "COMBOOT unknown int21 function %02x\n", ix86->regs.ah );
+ break;
+ }
+}
+
+
+/**
+ * SYSLINUX API
+ */
+static __cdecl void int22 ( struct i386_all_regs *ix86 ) {
+ ix86->flags |= CF;
+
+ switch ( ix86->regs.ax ) {
+ case 0x0001: /* Get Version */
+
+ /* Number of INT 22h API functions available */
+ ix86->regs.ax = 0x0018;
+
+ /* SYSLINUX version number */
+ ix86->regs.ch = 0; /* major */
+ ix86->regs.cl = 0; /* minor */
+
+ /* SYSLINUX derivative ID */
+ ix86->regs.dl = BZI_LOADER_TYPE_GPXE;
+
+ /* SYSLINUX version and copyright strings */
+ ix86->segs.es = rm_ds;
+ ix86->regs.si = ( ( unsigned ) __from_data16 ( syslinux_version ) );
+ ix86->regs.di = ( ( unsigned ) __from_data16 ( syslinux_copyright ) );
+
+ ix86->flags &= ~CF;
+ break;
+
+ case 0x0002: /* Write String */
+ print_user_string ( ix86->segs.es, ix86->regs.bx, '\0' );
+ ix86->flags &= ~CF;
+ break;
+
+ case 0x0003: /* Run command */
+ {
+ userptr_t cmd_u = real_to_user ( ix86->segs.es, ix86->regs.bx );
+ int len = strlen_user ( cmd_u, 0 );
+ char cmd[len + 1];
+ copy_from_user ( cmd, cmd_u, 0, len + 1 );
+ DBG ( "COMBOOT: executing command '%s'\n", cmd );
+
+ comboot_kernel_cmdline = strdup ( cmd );
+
+ DBG ( "COMBOOT: returning to run image...\n" );
+ longjmp ( comboot_return, COMBOOT_RETURN_RUN_KERNEL );
+ }
+ break;
+
+ case 0x0004: /* Run default command */
+ /* FIXME: just exit for now */
+ longjmp ( comboot_return, COMBOOT_RETURN_EXIT );
+ break;
+
+ case 0x0005: /* Force text mode */
+ comboot_force_text_mode ( );
+ ix86->flags &= ~CF;
+ break;
+
+ case 0x0006: /* Open file */
+ {
+ int fd;
+ userptr_t file_u = real_to_user ( ix86->segs.es, ix86->regs.si );
+ int len = strlen_user ( file_u, 0 );
+ char file[len + 1];
+
+ copy_from_user ( file, file_u, 0, len + 1 );
+
+ if ( file[0] == '\0' ) {
+ DBG ( "COMBOOT: attempted open with empty file name\n" );
+ break;
+ }
+
+ DBG ( "COMBOOT: opening file '%s'\n", file );
+
+ fd = open ( file );
+
+ if ( fd < 0 ) {
+ DBG ( "COMBOOT: error opening file %s\n", file );
+ break;
+ }
+
+ /* This relies on the fact that a gPXE POSIX fd will
+ * always fit in 16 bits.
+ */
+#if (POSIX_FD_MAX > 65535)
+#error POSIX_FD_MAX too large
+#endif
+ ix86->regs.si = (uint16_t) fd;
+
+ ix86->regs.cx = COMBOOT_FILE_BLOCKSZ;
+ ix86->regs.eax = fsize ( fd );
+ ix86->flags &= ~CF;
+ }
+ break;
+
+ case 0x0007: /* Read file */
+ {
+ int fd = ix86->regs.si;
+ int len = ix86->regs.cx * COMBOOT_FILE_BLOCKSZ;
+ int rc;
+ fd_set fds;
+ userptr_t buf = real_to_user ( ix86->segs.es, ix86->regs.bx );
+
+ /* Wait for data ready to read */
+ FD_ZERO ( &fds );
+ FD_SET ( fd, &fds );
+
+ select ( &fds, 1 );
+
+ rc = read_user ( fd, buf, 0, len );
+ if ( rc < 0 ) {
+ DBG ( "COMBOOT: read failed\n" );
+ ix86->regs.si = 0;
+ break;
+ }
+
+ ix86->regs.ecx = rc;
+ ix86->flags &= ~CF;
+ }
+ break;
+
+ case 0x0008: /* Close file */
+ {
+ int fd = ix86->regs.si;
+ close ( fd );
+ ix86->flags &= ~CF;
+ }
+ break;
+
+ case 0x0009: /* Call PXE Stack */
+ pxe_api_call ( ix86 );
+ ix86->flags &= ~CF;
+ break;
+
+ case 0x000A: /* Get Derivative-Specific Information */
+
+ /* gPXE has its own derivative ID, so there is no defined
+ * output here; just return AL for now */
+ ix86->regs.al = BZI_LOADER_TYPE_GPXE;
+ ix86->flags &= ~CF;
+ break;
+
+ case 0x000B: /* Get Serial Console Configuration */
+ /* FIXME: stub */
+ ix86->regs.dx = 0;
+ ix86->flags &= ~CF;
+ break;
+
+ case 0x000E: /* Get configuration file name */
+ /* FIXME: stub */
+ ix86->segs.es = rm_ds;
+ ix86->regs.bx = ( ( unsigned ) __from_data16 ( syslinux_configuration_file ) );
+ ix86->flags &= ~CF;
+ break;
+
+ case 0x000F: /* Get IPAPPEND strings */
+ /* FIXME: stub */
+ ix86->regs.cx = 0;
+ ix86->segs.es = 0;
+ ix86->regs.bx = 0;
+ ix86->flags &= ~CF;
+ break;
+
+ case 0x0010: /* Resolve hostname */
+ {
+ userptr_t hostname_u = real_to_user ( ix86->segs.es, ix86->regs.bx );
+ int len = strlen_user ( hostname_u, 0 );
+ char hostname[len];
+ struct in_addr addr;
+
+ copy_from_user ( hostname, hostname_u, 0, len + 1 );
+
+ /* TODO:
+ * "If the hostname does not contain a dot (.), the
+ * local domain name is automatically appended."
+ */
+
+ comboot_resolv ( hostname, &addr );
+
+ ix86->regs.eax = addr.s_addr;
+ ix86->flags &= ~CF;
+ }
+ break;
+
+ case 0x0011: /* Maximum number of shuffle descriptors */
+ ix86->regs.cx = COMBOOT_MAX_SHUFFLE_DESCRIPTORS;
+ ix86->flags &= ~CF;
+ break;
+
+ case 0x0012: /* Cleanup, shuffle and boot */
+ if ( ix86->regs.cx > COMBOOT_MAX_SHUFFLE_DESCRIPTORS )
+ break;
+
+ /* Perform final cleanup */
+ shutdown ( SHUTDOWN_BOOT );
+
+ /* Perform sequence of copies */
+ shuffle ( ix86->segs.es, ix86->regs.di, ix86->regs.cx );
+
+ /* Jump to real-mode entry point */
+ __asm__ __volatile__ (
+ REAL_CODE (
+ "pushw %0\n\t"
+ "popw %%ds\n\t"
+ "pushl %1\n\t"
+ "lret\n\t"
+ )
+ :
+ : "r" ( ix86->segs.ds ),
+ "r" ( ix86->regs.ebp ),
+ "d" ( ix86->regs.ebx ),
+ "S" ( ix86->regs.esi ) );
+
+ assert ( 0 ); /* Execution should never reach this point */
+
+ break;
+
+ case 0x0013: /* Idle loop call */
+ step ( );
+ ix86->flags &= ~CF;
+ break;
+
+ case 0x0015: /* Get feature flags */
+ ix86->segs.es = rm_ds;
+ ix86->regs.bx = ( ( unsigned ) __from_data16 ( &comboot_feature_flags ) );
+ ix86->regs.cx = 1; /* Number of feature flag bytes */
+ ix86->flags &= ~CF;
+ break;
+
+ case 0x0016: /* Run kernel image */
+ {
+ userptr_t file_u = real_to_user ( ix86->segs.ds, ix86->regs.si );
+ userptr_t cmd_u = real_to_user ( ix86->segs.es, ix86->regs.bx );
+ int file_len = strlen_user ( file_u, 0 );
+ int cmd_len = strlen_user ( cmd_u, 0 );
+ char file[file_len + 1 + cmd_len + 7 + 1];
+ char cmd[cmd_len + 1];
+
+ memcpy( file, "kernel ", 7 );
+ copy_from_user ( file + 7, file_u, 0, file_len + 1 );
+ copy_from_user ( cmd, cmd_u, 0, cmd_len + 1 );
+ strcat ( file, " " );
+ strcat ( file, cmd );
+
+ DBG ( "COMBOOT: run kernel image '%s'\n", file );
+
+ comboot_kernel_cmdline = strdup ( file );
+
+ DBG ( "COMBOOT: returning to run image...\n" );
+ longjmp ( comboot_return, COMBOOT_RETURN_RUN_KERNEL );
+ }
+ break;
+
+ case 0x0017: /* Report video mode change */
+ comboot_graphics_mode = ix86->regs.bx;
+ ix86->flags &= ~CF;
+ break;
+
+ case 0x0018: /* Query custom font */
+ /* FIXME: stub */
+ ix86->regs.al = 0;
+ ix86->segs.es = 0;
+ ix86->regs.bx = 0;
+ ix86->flags &= ~CF;
+ break;
+
+ default:
+ DBG ( "COMBOOT unknown int22 function %04x\n", ix86->regs.ax );
+ break;
+ }
+}
+
+/**
+ * Hook BIOS interrupts related to COMBOOT API (INT 20h, 21h, 22h)
+ */
+void hook_comboot_interrupts ( ) {
+
+ __asm__ __volatile__ (
+ TEXT16_CODE ( "\nint20_wrapper:\n\t"
+ "pushl %0\n\t"
+ "pushw %%cs\n\t"
+ "call prot_call\n\t"
+ "addw $4, %%sp\n\t"
+ "iret\n\t" )
+ : : "i" ( int20 ) );
+
+ hook_bios_interrupt ( 0x20, ( unsigned int ) int20_wrapper,
+ &int20_vector );
+
+ __asm__ __volatile__ (
+ TEXT16_CODE ( "\nint21_wrapper:\n\t"
+ "pushl %0\n\t"
+ "pushw %%cs\n\t"
+ "call prot_call\n\t"
+ "addw $4, %%sp\n\t"
+ "iret\n\t" )
+ : : "i" ( int21 ) );
+
+ hook_bios_interrupt ( 0x21, ( unsigned int ) int21_wrapper,
+ &int21_vector );
+
+ __asm__ __volatile__ (
+ TEXT16_CODE ( "\nint22_wrapper:\n\t"
+ "pushl %0\n\t"
+ "pushw %%cs\n\t"
+ "call prot_call\n\t"
+ "addw $4, %%sp\n\t"
+ "iret\n\t" )
+ : : "i" ( int22) );
+
+ hook_bios_interrupt ( 0x22, ( unsigned int ) int22_wrapper,
+ &int22_vector );
+}
generated by cgit v1.2.3-55-g7522 (git 2.39.0) at 2024-05-23 15:01:30 +0200