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Diffstat (limited to '')
-rw-r--r-- | kexec/arch/i386/kexec-nbi.c | 249 |
1 files changed, 249 insertions, 0 deletions
diff --git a/kexec/arch/i386/kexec-nbi.c b/kexec/arch/i386/kexec-nbi.c new file mode 100644 index 0000000..8eb2154 --- /dev/null +++ b/kexec/arch/i386/kexec-nbi.c @@ -0,0 +1,249 @@ +/* + * kexec: Linux boots Linux + * + * Copyright (C) 2005 Eric Biederman (ebiederm@xmission.com) + * + * 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 (version 2 of the License). + * + * 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. + */ +#define _GNU_SOURCE +#include <stdio.h> +#include <string.h> +#include <stdlib.h> +#include <errno.h> +#include <limits.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <unistd.h> +#include <getopt.h> +#include <elf.h> +#include "../../kexec.h" +#include "../../kexec-elf.h" +#include "../../kexec-elf-boot.h" +#include "kexec-x86.h" +#include <arch/options.h> + +struct segheader +{ + uint8_t length; + uint8_t vendortag; + uint8_t reserved; + uint8_t flags; +#define NBI_SEG 0x3 +#define NBI_SEG_ABSOLUTE 0 +#define NBI_SEG_APPEND 1 +#define NBI_SEG_NEGATIVE 2 +#define NBI_SEG_PREPEND 3 +#define NBI_LAST_SEG (1 << 2) + uint32_t loadaddr; + uint32_t imglength; + uint32_t memlength; +}; + +struct imgheader +{ +#define NBI_MAGIC "\x36\x13\x03\x1b" + uint8_t magic[4]; +#define NBI_RETURNS (1 << 8) +#define NBI_ENTRY32 (1 << 31) + uint32_t length; /* and flags */ + struct { uint16_t bx, ds; } segoff; + union { + struct { uint16_t ip, cs; } segoff; + uint32_t linear; + } execaddr; +}; + + +static const int probe_debug = 0; + +int nbi_probe(const char *buf, off_t len) +{ + struct imgheader hdr; + struct segheader seg; + off_t seg_off; + /* If we don't have enough data give up */ + if (((uintmax_t)len < (uintmax_t)sizeof(hdr)) || (len < 512)) { + return -1; + } + memcpy(&hdr, buf, sizeof(hdr)); + if (memcmp(hdr.magic, NBI_MAGIC, sizeof(hdr.magic)) != 0) { + return -1; + } + /* Ensure we have a properly sized header */ + if (((hdr.length & 0xf)*4) != sizeof(hdr)) { + if (probe_debug) { + fprintf(stderr, "NBI: Bad vendor header size\n"); + } + return -1; + } + /* Ensure the vendor header is not too large. + * This can't actually happen but.... + */ + if ((((hdr.length & 0xf0) >> 4)*4) > (512 - sizeof(hdr))) { + if (probe_debug) { + fprintf(stderr, "NBI: vendor headr too large\n"); + } + return -1; + } + /* Reserved bits are set in the image... */ + if ((hdr.length & 0x7ffffe00)) { + if (probe_debug) { + fprintf(stderr, "NBI: Reserved header bits set\n"); + } + return -1; + } + /* If the image can return refuse to load it */ + if (hdr.length & (1 << 8)) { + if (probe_debug) { + printf("NBI: image wants to return\n"); + } + return -1; + } + /* Now verify the segments all fit within 512 bytes */ + seg_off = (((hdr.length & 0xf0) >> 4) + (hdr.length & 0x0f)) << 2; + do { + memcpy(&seg, buf + seg_off, sizeof(seg)); + if ((seg.length & 0xf) != 4) { + if (probe_debug) { + fprintf(stderr, "NBI: Invalid segment length\n"); + } + return -1; + } + seg_off += ((seg.length & 0xf) + ((seg.length >> 4) & 0xf)) << 2; + if (seg.flags & 0xf8) { + if (probe_debug) { + fprintf(stderr, "NBI: segment reserved flags set\n"); + } + return -1; + } + if ((seg.flags & NBI_SEG) == NBI_SEG_NEGATIVE) { + if (probe_debug) { + fprintf(stderr, "NBI: negative segment addresses not supported\n"); + } + return -1; + } + if (seg_off > 512) { + if (probe_debug) { + fprintf(stderr, "NBI: segment outside 512 header\n"); + } + return -1; + } + } while(!(seg.flags & NBI_LAST_SEG)); + return 0; +} + +void nbi_usage(void) +{ + printf( "\n" + ); +} + +int nbi_load(int argc, char **argv, const char *buf, off_t UNUSED(len), + struct kexec_info *info) +{ + struct imgheader hdr; + struct segheader seg; + off_t seg_off; + off_t file_off; + uint32_t last0, last1; + int opt; + + static const struct option options[] = { + KEXEC_ARCH_OPTIONS + { 0, 0, NULL, 0 }, + }; + + static const char short_options[] = KEXEC_OPT_STR ""; + + /* + * Parse the command line arguments + */ + while((opt = getopt_long(argc, argv, short_options, options, 0)) != -1) { + switch(opt) { + default: + /* Ignore core options */ + if (opt < OPT_ARCH_MAX) { + break; + } + } + } + /* Get a copy of the header */ + memcpy(&hdr, buf, sizeof(hdr)); + + /* Load the first 512 bytes */ + add_segment(info, buf + 0, 512, + (hdr.segoff.ds << 4) + hdr.segoff.bx, 512); + + /* Initialize variables */ + file_off = 512; + last0 = (hdr.segoff.ds << 4) + hdr.segoff.bx; + last1 = last0 + 512; + + /* Load the segments */ + seg_off = (((hdr.length & 0xf0) >> 4) + (hdr.length & 0x0f)) << 2; + do { + uint32_t loadaddr; + memcpy(&seg, buf + seg_off, sizeof(seg)); + seg_off += ((seg.length & 0xf) + ((seg.length >> 4) & 0xf)) << 2; + if ((seg.flags & NBI_SEG) == NBI_SEG_ABSOLUTE) { + loadaddr = seg.loadaddr; + } + else if ((seg.flags & NBI_SEG) == NBI_SEG_APPEND) { + loadaddr = last1 + seg.loadaddr; + } +#if 0 + else if ((seg.flags & NBI_SEG) == NBI_SEG_NEGATIVE) { + loadaddr = memsize - seg.loadaddr; + } +#endif + else if ((seg.flags & NBI_SEG) == NBI_SEG_PREPEND) { + loadaddr = last0 - seg.loadaddr; + } + else { + printf("warning: unhandled segment of type %0x\n", + seg.flags & NBI_SEG); + continue; + } + add_segment(info, buf + file_off, seg.imglength, + loadaddr, seg.memlength); + last0 = loadaddr; + last1 = last0 + seg.memlength; + file_off += seg.imglength; + } while(!(seg.flags & NBI_LAST_SEG)); + + if (hdr.length & NBI_ENTRY32) { + struct entry32_regs regs32; + /* Initialize the registers */ + elf_rel_get_symbol(&info->rhdr, "entry32_regs32", ®s32, sizeof(regs32)); + regs32.eip = hdr.execaddr.linear; + elf_rel_set_symbol(&info->rhdr, "entry32_regs32", ®s32, sizeof(regs32)); + } + else { + struct entry32_regs regs32; + struct entry16_regs regs16; + + /* Initialize the 16 bit registers */ + elf_rel_get_symbol(&info->rhdr, "entry16_regs", ®s16, sizeof(regs16)); + regs16.cs = hdr.execaddr.segoff.cs; + regs16.ip = hdr.execaddr.segoff.ip; + elf_rel_set_symbol(&info->rhdr, "entry16_regs", ®s16, sizeof(regs16)); + + /* Initialize the 32 bit registers */ + elf_rel_get_symbol(&info->rhdr, "entry32_regs", ®s32, sizeof(regs32)); + regs32.eip = elf_rel_get_addr(&info->rhdr, "entry16"); + elf_rel_set_symbol(&info->rhdr, "entry32_regs", ®s32, sizeof(regs32)); + } + return 0; +} |