1 files changed, 561 insertions, 0 deletions

diff --git a/contrib/syslinux-4.02/gpxe/src/arch/i386/image/bzimage.c b/contrib/syslinux-4.02/gpxe/src/arch/i386/image/bzimage.c
new file mode 100644
index 0000000..1945099
--- /dev/null
+++ b/contrib/syslinux-4.02/gpxe/src/arch/i386/image/bzimage.c
@@ -0,0 +1,561 @@
+/*
+ * Copyright (C) 2007 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * 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_LICENCE ( GPL2_OR_LATER );
+
+/**
+ * @file
+ *
+ * Linux bzImage image format
+ *
+ */
+
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <assert.h>
+#include <realmode.h>
+#include <bzimage.h>
+#include <gpxe/uaccess.h>
+#include <gpxe/image.h>
+#include <gpxe/segment.h>
+#include <gpxe/init.h>
+#include <gpxe/cpio.h>
+#include <gpxe/features.h>
+
+FEATURE ( FEATURE_IMAGE, "bzImage", DHCP_EB_FEATURE_BZIMAGE, 1 );
+
+struct image_type bzimage_image_type __image_type ( PROBE_NORMAL );
+
+/**
+ * bzImage context
+ */
+struct bzimage_context {
+	/** Boot protocol version */
+	unsigned int version;
+	/** Real-mode kernel portion load segment address */
+	unsigned int rm_kernel_seg;
+	/** Real-mode kernel portion load address */
+	userptr_t rm_kernel;
+	/** Real-mode kernel portion file size */
+	size_t rm_filesz;
+	/** Real-mode heap top (offset from rm_kernel) */
+	size_t rm_heap;
+	/** Command line (offset from rm_kernel) */
+	size_t rm_cmdline;
+	/** Command line maximum length */
+	size_t cmdline_size;
+	/** Real-mode kernel portion total memory size */
+	size_t rm_memsz;
+	/** Non-real-mode kernel portion load address */
+	userptr_t pm_kernel;
+	/** Non-real-mode kernel portion file and memory size */
+	size_t pm_sz;
+	/** Video mode */
+	unsigned int vid_mode;
+	/** Memory limit */
+	uint64_t mem_limit;
+	/** Initrd address */
+	physaddr_t ramdisk_image;
+	/** Initrd size */
+	physaddr_t ramdisk_size;
+
+	/** Command line magic block */
+	struct bzimage_cmdline cmdline_magic;
+	/** bzImage header */
+	struct bzimage_header bzhdr;
+};
+
+/**
+ * Parse bzImage header
+ *
+ * @v image		bzImage file
+ * @v bzimg		bzImage context
+ * @v src		bzImage to parse
+ * @ret rc		Return status code
+ */
+static int bzimage_parse_header ( struct image *image,
+				  struct bzimage_context *bzimg,
+				  userptr_t src ) {
+	unsigned int syssize;
+	int is_bzimage;
+
+	/* Sanity check */
+	if ( image->len < ( BZI_HDR_OFFSET + sizeof ( bzimg->bzhdr ) ) ) {
+		DBGC ( image, "bzImage %p too short for kernel header\n",
+		       image );
+		return -ENOEXEC;
+	}
+
+	/* Read in header structures */
+	memset ( bzimg, 0, sizeof ( *bzimg ) );
+	copy_from_user ( &bzimg->cmdline_magic, src, BZI_CMDLINE_OFFSET,
+			 sizeof ( bzimg->cmdline_magic ) );
+	copy_from_user ( &bzimg->bzhdr, src, BZI_HDR_OFFSET,
+			 sizeof ( bzimg->bzhdr ) );
+
+	/* Calculate size of real-mode portion */
+	bzimg->rm_filesz =
+		( ( bzimg->bzhdr.setup_sects ? bzimg->bzhdr.setup_sects : 4 ) + 1 ) << 9;
+	if ( bzimg->rm_filesz > image->len ) {
+		DBGC ( image, "bzImage %p too short for %zd byte of setup\n",
+		       image, bzimg->rm_filesz );
+		return -ENOEXEC;
+	}
+	bzimg->rm_memsz = BZI_ASSUMED_RM_SIZE;
+
+	/* Calculate size of protected-mode portion */
+	bzimg->pm_sz = ( image->len - bzimg->rm_filesz );
+	syssize = ( ( bzimg->pm_sz + 15 ) / 16 );
+
+	/* Check for signatures and determine version */
+	if ( bzimg->bzhdr.boot_flag != BZI_BOOT_FLAG ) {
+		DBGC ( image, "bzImage %p missing 55AA signature\n", image );
+		return -ENOEXEC;
+	}
+	if ( bzimg->bzhdr.header == BZI_SIGNATURE ) {
+		/* 2.00+ */
+		bzimg->version = bzimg->bzhdr.version;
+	} else {
+		/* Pre-2.00.  Check that the syssize field is correct,
+		 * as a guard against accepting arbitrary binary data,
+		 * since the 55AA check is pretty lax.  Note that the
+		 * syssize field is unreliable for protocols between
+		 * 2.00 and 2.03 inclusive, so we should not always
+		 * check this field.
+		 */
+		bzimg->version = 0x0100;
+		if ( bzimg->bzhdr.syssize != syssize ) {
+			DBGC ( image, "bzImage %p bad syssize %x (expected "
+			       "%x)\n", image, bzimg->bzhdr.syssize, syssize );
+			return -ENOEXEC;
+		}
+	}
+
+	/* Determine image type */
+	is_bzimage = ( ( bzimg->version >= 0x0200 ) ?
+		       ( bzimg->bzhdr.loadflags & BZI_LOAD_HIGH ) : 0 );
+
+	/* Calculate load address of real-mode portion */
+	bzimg->rm_kernel_seg = ( is_bzimage ? 0x1000 : 0x9000 );
+	bzimg->rm_kernel = real_to_user ( bzimg->rm_kernel_seg, 0 );
+
+	/* Allow space for the stack and heap */
+	bzimg->rm_memsz += BZI_STACK_SIZE;
+	bzimg->rm_heap = bzimg->rm_memsz;
+
+	/* Allow space for the command line */
+	bzimg->rm_cmdline = bzimg->rm_memsz;
+	bzimg->rm_memsz += BZI_CMDLINE_SIZE;
+
+	/* Calculate load address of protected-mode portion */
+	bzimg->pm_kernel = phys_to_user ( is_bzimage ? BZI_LOAD_HIGH_ADDR
+					: BZI_LOAD_LOW_ADDR );
+
+	/* Extract video mode */
+	bzimg->vid_mode = bzimg->bzhdr.vid_mode;
+
+	/* Extract memory limit */
+	bzimg->mem_limit = ( ( bzimg->version >= 0x0203 ) ?
+			     bzimg->bzhdr.initrd_addr_max : BZI_INITRD_MAX );
+
+	/* Extract command line size */
+	bzimg->cmdline_size = ( ( bzimg->version >= 0x0206 ) ?
+				bzimg->bzhdr.cmdline_size : BZI_CMDLINE_SIZE );
+
+	DBGC ( image, "bzImage %p version %04x RM %#lx+%#zx PM %#lx+%#zx "
+	       "cmdlen %zd\n", image, bzimg->version,
+	       user_to_phys ( bzimg->rm_kernel, 0 ), bzimg->rm_filesz,
+	       user_to_phys ( bzimg->pm_kernel, 0 ), bzimg->pm_sz,
+	       bzimg->cmdline_size );
+
+	return 0;
+}
+
+/**
+ * Update bzImage header in loaded kernel
+ *
+ * @v image		bzImage file
+ * @v bzimg		bzImage context
+ * @v dst		bzImage to update
+ */
+static void bzimage_update_header ( struct image *image,
+				    struct bzimage_context *bzimg,
+				    userptr_t dst ) {
+
+	/* Set loader type */
+	if ( bzimg->version >= 0x0200 )
+		bzimg->bzhdr.type_of_loader = BZI_LOADER_TYPE_GPXE;
+
+	/* Set heap end pointer */
+	if ( bzimg->version >= 0x0201 ) {
+		bzimg->bzhdr.heap_end_ptr = ( bzimg->rm_heap - 0x200 );
+		bzimg->bzhdr.loadflags |= BZI_CAN_USE_HEAP;
+	}
+
+	/* Set command line */
+	if ( bzimg->version >= 0x0202 ) {
+		bzimg->bzhdr.cmd_line_ptr = user_to_phys ( bzimg->rm_kernel,
+							   bzimg->rm_cmdline );
+	} else {
+		bzimg->cmdline_magic.magic = BZI_CMDLINE_MAGIC;
+		bzimg->cmdline_magic.offset = bzimg->rm_cmdline;
+		bzimg->bzhdr.setup_move_size = bzimg->rm_memsz;
+	}
+
+	/* Set video mode */
+	bzimg->bzhdr.vid_mode = bzimg->vid_mode;
+
+	/* Set initrd address */
+	if ( bzimg->version >= 0x0200 ) {
+		bzimg->bzhdr.ramdisk_image = bzimg->ramdisk_image;
+		bzimg->bzhdr.ramdisk_size = bzimg->ramdisk_size;
+	}
+
+	/* Write out header structures */
+	copy_to_user ( dst, BZI_CMDLINE_OFFSET, &bzimg->cmdline_magic,
+		       sizeof ( bzimg->cmdline_magic ) );
+	copy_to_user ( dst, BZI_HDR_OFFSET, &bzimg->bzhdr,
+		       sizeof ( bzimg->bzhdr ) );
+
+	DBGC ( image, "bzImage %p vidmode %d\n", image, bzimg->vid_mode );
+}
+
+/**
+ * Parse kernel command line for bootloader parameters
+ *
+ * @v image		bzImage file
+ * @v bzimg		bzImage context
+ * @v cmdline		Kernel command line
+ * @ret rc		Return status code
+ */
+static int bzimage_parse_cmdline ( struct image *image,
+				   struct bzimage_context *bzimg,
+				   const char *cmdline ) {
+	char *vga;
+	char *mem;
+
+	/* Look for "vga=" */
+	if ( ( vga = strstr ( cmdline, "vga=" ) ) ) {
+		vga += 4;
+		if ( strcmp ( vga, "normal" ) == 0 ) {
+			bzimg->vid_mode = BZI_VID_MODE_NORMAL;
+		} else if ( strcmp ( vga, "ext" ) == 0 ) {
+			bzimg->vid_mode = BZI_VID_MODE_EXT;
+		} else if ( strcmp ( vga, "ask" ) == 0 ) {
+			bzimg->vid_mode = BZI_VID_MODE_ASK;
+		} else {
+			bzimg->vid_mode = strtoul ( vga, &vga, 0 );
+			if ( *vga && ( *vga != ' ' ) ) {
+				DBGC ( image, "bzImage %p strange \"vga=\""
+				       "terminator '%c'\n", image, *vga );
+			}
+		}
+	}
+
+	/* Look for "mem=" */
+	if ( ( mem = strstr ( cmdline, "mem=" ) ) ) {
+		mem += 4;
+		bzimg->mem_limit = strtoul ( mem, &mem, 0 );
+		switch ( *mem ) {
+		case 'G':
+		case 'g':
+			bzimg->mem_limit <<= 10;
+		case 'M':
+		case 'm':
+			bzimg->mem_limit <<= 10;
+		case 'K':
+		case 'k':
+			bzimg->mem_limit <<= 10;
+			break;
+		case '\0':
+		case ' ':
+			break;
+		default:
+			DBGC ( image, "bzImage %p strange \"mem=\" "
+			       "terminator '%c'\n", image, *mem );
+			break;
+		}
+		bzimg->mem_limit -= 1;
+	}
+
+	return 0;
+}
+
+/**
+ * Set command line
+ *
+ * @v image		bzImage image
+ * @v bzimg		bzImage context
+ * @v cmdline		Kernel command line
+ * @ret rc		Return status code
+ */
+static int bzimage_set_cmdline ( struct image *image,
+				 struct bzimage_context *bzimg,
+				 const char *cmdline ) {
+	size_t cmdline_len;
+
+	/* Copy command line down to real-mode portion */
+	cmdline_len = ( strlen ( cmdline ) + 1 );
+	if ( cmdline_len > bzimg->cmdline_size )
+		cmdline_len = bzimg->cmdline_size;
+	copy_to_user ( bzimg->rm_kernel, bzimg->rm_cmdline,
+		       cmdline, cmdline_len );
+	DBGC ( image, "bzImage %p command line \"%s\"\n", image, cmdline );
+
+	return 0;
+}
+
+/**
+ * Load initrd
+ *
+ * @v image		bzImage image
+ * @v initrd		initrd image
+ * @v address		Address at which to load, or UNULL
+ * @ret len		Length of loaded image, rounded up to 4 bytes
+ */
+static size_t bzimage_load_initrd ( struct image *image,
+				    struct image *initrd,
+				    userptr_t address ) {
+	char *filename = initrd->cmdline;
+	struct cpio_header cpio;
+        size_t offset = 0;
+
+	/* Do not include kernel image itself as an initrd */
+	if ( initrd == image )
+		return 0;
+
+	/* Create cpio header before non-prebuilt images */
+	if ( filename && filename[0] ) {
+		size_t name_len = ( strlen ( filename ) + 1 );
+
+		DBGC ( image, "bzImage %p inserting initrd %p as %s\n",
+		       image, initrd, filename );
+		memset ( &cpio, '0', sizeof ( cpio ) );
+		memcpy ( cpio.c_magic, CPIO_MAGIC, sizeof ( cpio.c_magic ) );
+		cpio_set_field ( cpio.c_mode, 0100644 );
+		cpio_set_field ( cpio.c_nlink, 1 );
+		cpio_set_field ( cpio.c_filesize, initrd->len );
+		cpio_set_field ( cpio.c_namesize, name_len );
+		if ( address ) {
+			copy_to_user ( address, offset, &cpio,
+				       sizeof ( cpio ) );
+		}
+		offset += sizeof ( cpio );
+		if ( address ) {
+			copy_to_user ( address, offset, filename,
+				       name_len );
+		}
+		offset += name_len;
+		offset = ( ( offset + 0x03 ) & ~0x03 );
+	}
+
+	/* Copy in initrd image body */
+	if ( address )
+		memcpy_user ( address, offset, initrd->data, 0, initrd->len );
+	offset += initrd->len;
+	if ( address ) {
+		DBGC ( image, "bzImage %p has initrd %p at [%lx,%lx)\n",
+		       image, initrd, user_to_phys ( address, 0 ),
+		       user_to_phys ( address, offset ) );
+	}
+
+	/* Round up to 4-byte boundary */
+	offset = ( ( offset + 0x03 ) & ~0x03 );
+	return offset;
+}
+
+/**
+ * Load initrds, if any
+ *
+ * @v image		bzImage image
+ * @v bzimg		bzImage context
+ * @ret rc		Return status code
+ */
+static int bzimage_load_initrds ( struct image *image,
+				  struct bzimage_context *bzimg ) {
+	struct image *initrd;
+	size_t total_len = 0;
+	physaddr_t address;
+	int rc;
+
+	/* Add up length of all initrd images */
+	for_each_image ( initrd )
+		total_len += bzimage_load_initrd ( image, initrd, UNULL );
+
+	/* Give up if no initrd images found */
+	if ( ! total_len )
+		return 0;
+
+	/* Find a suitable start address.  Try 1MB boundaries,
+	 * starting from the downloaded kernel image itself and
+	 * working downwards until we hit an available region.
+	 */
+	for ( address = ( user_to_phys ( image->data, 0 ) & ~0xfffff ) ; ;
+	      address -= 0x100000 ) {
+		/* Check that we're not going to overwrite the
+		 * kernel itself.  This check isn't totally
+		 * accurate, but errs on the side of caution.
+		 */
+		if ( address <= ( BZI_LOAD_HIGH_ADDR + image->len ) ) {
+			DBGC ( image, "bzImage %p could not find a location "
+			       "for initrd\n", image );
+			return -ENOBUFS;
+		}
+		/* Check that we are within the kernel's range */
+		if ( ( address + total_len - 1 ) > bzimg->mem_limit )
+			continue;
+		/* Prepare and verify segment */
+		if ( ( rc = prep_segment ( phys_to_user ( address ), 0,
+					   total_len ) ) != 0 )
+			continue;
+		/* Use this address */
+		break;
+	}
+
+	/* Record initrd location */
+	bzimg->ramdisk_image = address;
+	bzimg->ramdisk_size = total_len;
+
+	/* Construct initrd */
+	DBGC ( image, "bzImage %p constructing initrd at [%lx,%lx)\n",
+	       image, address, ( address + total_len ) );
+	for_each_image ( initrd ) {
+		address += bzimage_load_initrd ( image, initrd,
+						 phys_to_user ( address ) );
+	}
+
+	return 0;
+}
+
+/**
+ * Execute bzImage image
+ *
+ * @v image		bzImage image
+ * @ret rc		Return status code
+ */
+static int bzimage_exec ( struct image *image ) {
+	struct bzimage_context bzimg;
+	const char *cmdline = ( image->cmdline ? image->cmdline : "" );
+	int rc;
+
+	/* Read and parse header from loaded kernel */
+	if ( ( rc = bzimage_parse_header ( image, &bzimg,
+					   image->priv.user ) ) != 0 )
+		return rc;
+	assert ( bzimg.rm_kernel == image->priv.user );
+
+	/* Parse command line for bootloader parameters */
+	if ( ( rc = bzimage_parse_cmdline ( image, &bzimg, cmdline ) ) != 0)
+		return rc;
+
+	/* Store command line */
+	if ( ( rc = bzimage_set_cmdline ( image, &bzimg, cmdline ) ) != 0 )
+		return rc;
+
+	/* Load any initrds */
+	if ( ( rc = bzimage_load_initrds ( image, &bzimg ) ) != 0 )
+		return rc;
+
+	/* Update kernel header */
+	bzimage_update_header ( image, &bzimg, bzimg.rm_kernel );
+
+	/* Prepare for exiting */
+	shutdown ( SHUTDOWN_BOOT );
+
+	DBGC ( image, "bzImage %p jumping to RM kernel at %04x:0000 "
+	       "(stack %04x:%04zx)\n", image, ( bzimg.rm_kernel_seg + 0x20 ),
+	       bzimg.rm_kernel_seg, bzimg.rm_heap );
+
+	/* Jump to the kernel */
+	__asm__ __volatile__ ( REAL_CODE ( "movw %w0, %%ds\n\t"
+					   "movw %w0, %%es\n\t"
+					   "movw %w0, %%fs\n\t"
+					   "movw %w0, %%gs\n\t"
+					   "movw %w0, %%ss\n\t"
+					   "movw %w1, %%sp\n\t"
+					   "pushw %w2\n\t"
+					   "pushw $0\n\t"
+					   "lret\n\t" )
+			       : : "r" ( bzimg.rm_kernel_seg ),
+			           "r" ( bzimg.rm_heap ),
+			           "r" ( bzimg.rm_kernel_seg + 0x20 ) );
+
+	/* There is no way for the image to return, since we provide
+	 * no return address.
+	 */
+	assert ( 0 );
+
+	return -ECANCELED; /* -EIMPOSSIBLE */
+}
+
+/**
+ * Load bzImage image into memory
+ *
+ * @v image		bzImage file
+ * @ret rc		Return status code
+ */
+int bzimage_load ( struct image *image ) {
+	struct bzimage_context bzimg;
+	int rc;
+
+	/* Read and parse header from image */
+	if ( ( rc = bzimage_parse_header ( image, &bzimg,
+					   image->data ) ) != 0 )
+		return rc;
+
+	/* This is a bzImage image, valid or otherwise */
+	if ( ! image->type )
+		image->type = &bzimage_image_type;
+
+	/* Prepare segments */
+	if ( ( rc = prep_segment ( bzimg.rm_kernel, bzimg.rm_filesz,
+				   bzimg.rm_memsz ) ) != 0 ) {
+		DBGC ( image, "bzImage %p could not prepare RM segment: %s\n",
+		       image, strerror ( rc ) );
+		return rc;
+	}
+	if ( ( rc = prep_segment ( bzimg.pm_kernel, bzimg.pm_sz,
+				   bzimg.pm_sz ) ) != 0 ) {
+		DBGC ( image, "bzImage %p could not prepare PM segment: %s\n",
+		       image, strerror ( rc ) );
+		return rc;
+	}
+
+	/* Load segments */
+	memcpy_user ( bzimg.rm_kernel, 0, image->data,
+		      0, bzimg.rm_filesz );
+	memcpy_user ( bzimg.pm_kernel, 0, image->data,
+		      bzimg.rm_filesz, bzimg.pm_sz );
+
+	/* Update and write out header */
+	bzimage_update_header ( image, &bzimg, bzimg.rm_kernel );
+
+	/* Record real-mode segment in image private data field */
+	image->priv.user = bzimg.rm_kernel;
+
+	return 0;
+}
+
+/** Linux bzImage image type */
+struct image_type bzimage_image_type __image_type ( PROBE_NORMAL ) = {
+	.name = "bzImage",
+	.load = bzimage_load,
+	.exec = bzimage_exec,
+};