2 * GRUB -- GRand Unified Bootloader
3 * Copyright (C) 2013 Free Software Foundation, Inc.
5 * GRUB is free software: you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation, either version 3 of the License, or
8 * (at your option) any later version.
10 * GRUB is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with GRUB. If not, see <http://www.gnu.org/licenses/>.
19 #include <grub/xen_file.h>
20 #include <grub/i386/linux.h>
21 #include <grub/misc.h>
23 #define XZ_MAGIC "\3757zXZ\0"
26 grub_xen_file (grub_file_t file)
29 struct linux_i386_kernel_header lh;
31 grub_uint32_t payload_offset, payload_length;
32 grub_uint8_t magic[6];
34 elf = grub_elf_file (file, file->name);
37 grub_errno = GRUB_ERR_NONE;
39 if (grub_file_seek (file, 0) == (grub_off_t) -1)
42 if (grub_file_read (file, &lh, sizeof (lh)) != sizeof (lh))
45 if (lh.boot_flag != grub_cpu_to_le16_compile_time (0xaa55)
46 || lh.header != grub_cpu_to_le32_compile_time (GRUB_LINUX_I386_MAGIC_SIGNATURE)
47 || grub_le_to_cpu16 (lh.version) < 0x0208)
49 grub_error (GRUB_ERR_BAD_OS, "version too old for xen boot");
53 payload_length = lh.payload_length;
54 payload_offset = (lh.setup_sects + 1) * 512
57 if (payload_length < sizeof (magic))
59 grub_error (GRUB_ERR_BAD_OS, "payload too short");
63 grub_dprintf ("xen", "found bzimage payload 0x%llx-0x%llx\n",
64 (unsigned long long) payload_offset,
65 (unsigned long long) lh.payload_length);
67 grub_file_seek (file, payload_offset);
69 if (grub_file_read (file, &magic, sizeof (magic)) != sizeof (magic))
72 grub_error (GRUB_ERR_BAD_OS, N_("premature end of file %s"),
77 /* Kernel suffixes xz payload with their uncompressed size.
79 if (grub_memcmp (magic, XZ_MAGIC, sizeof (XZ_MAGIC) - 1) == 0)
81 off_file = grub_file_offset_open (file, payload_offset,
86 elf = grub_elf_file (off_file, file->name);
89 grub_file_offset_close (off_file);
92 grub_error (GRUB_ERR_BAD_OS, "not xen image");
97 grub_xen_get_info (grub_elf_t elf, struct grub_xen_file_info * xi)
99 grub_memset (xi, 0, sizeof (*xi));
101 if (grub_elf_is_elf64 (elf)
102 && elf->ehdr.ehdr64.e_machine
103 == grub_cpu_to_le16_compile_time (EM_X86_64)
104 && elf->ehdr.ehdr64.e_ident[EI_DATA] == ELFDATA2LSB)
106 xi->arch = GRUB_XEN_FILE_X86_64;
107 return grub_xen_get_info64 (elf, xi);
109 if (grub_elf_is_elf32 (elf)
110 && elf->ehdr.ehdr32.e_machine == grub_cpu_to_le16_compile_time (EM_386)
111 && elf->ehdr.ehdr32.e_ident[EI_DATA] == ELFDATA2LSB)
113 xi->arch = GRUB_XEN_FILE_I386;
114 return grub_xen_get_info32 (elf, xi);
116 return grub_error (GRUB_ERR_BAD_OS, "unknown ELF type");