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-rw-r--r--contrib/syslinux-4.02/com32/mboot/map.c353
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diff --git a/contrib/syslinux-4.02/com32/mboot/map.c b/contrib/syslinux-4.02/com32/mboot/map.c
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+++ b/contrib/syslinux-4.02/com32/mboot/map.c
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+/* ----------------------------------------------------------------------- *
+ *
+ * Copyright 2007-2008 H. Peter Anvin - All Rights Reserved
+ * Copyright 2009-2010 Intel Corporation; author: H. Peter Anvin
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom
+ * the Software is furnished to do so, subject to the following
+ * conditions:
+ *
+ * The above copyright notice and this permission notice shall
+ * be included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * map.c
+ *
+ * Functions that deal with the memory map of various objects
+ */
+
+#include "mboot.h"
+
+static struct syslinux_movelist *ml = NULL;
+static struct syslinux_memmap *mmap = NULL, *amap = NULL;
+static addr_t mboot_high_water_mark = 0x100000;
+
+/*
+ * Note: although there is no such thing in the spec, at least Xen makes
+ * assumptions as to where in the memory space Grub would have loaded
+ * certain things. To support that, if "high" is set, then allocate this
+ * at an address strictly above any previous allocations.
+ *
+ * As a precaution, this also pads the data with zero up to the next
+ * alignment datum.
+ */
+addr_t map_data(const void *data, size_t len, size_t align, int flags)
+{
+ addr_t start = (flags & MAP_HIGH) ? mboot_high_water_mark : 0x2000;
+ addr_t pad = (flags & MAP_NOPAD) ? 0 : -len & (align - 1);
+ addr_t xlen = len + pad;
+
+ if (syslinux_memmap_find(amap, SMT_FREE, &start, &xlen, align) ||
+ syslinux_add_memmap(&amap, start, len + pad, SMT_ALLOC) ||
+ syslinux_add_movelist(&ml, start, (addr_t) data, len) ||
+ (pad && syslinux_add_memmap(&mmap, start + len, pad, SMT_ZERO))) {
+ printf("Cannot map %zu bytes\n", len + pad);
+ return 0;
+ }
+
+ dprintf("Mapping 0x%08x bytes (%#x pad) at 0x%08x\n", len, pad, start);
+
+ if (start + len + pad > mboot_high_water_mark)
+ mboot_high_water_mark = start + len + pad;
+
+ return start;
+}
+
+addr_t map_string(const char *string)
+{
+ if (!string)
+ return 0;
+ else
+ return map_data(string, strlen(string) + 1, 1, 0);
+}
+
+int init_map(void)
+{
+ /*
+ * Note: mmap is the memory map (containing free and zeroed regions)
+ * needed by syslinux_shuffle_boot_pm(); amap is a map where we keep
+ * track ourselves which target memory ranges have already been
+ * allocated.
+ */
+ mmap = syslinux_memory_map();
+ amap = syslinux_dup_memmap(mmap);
+ if (!mmap || !amap) {
+ error("Failed to allocate initial memory map!\n");
+ return -1;
+ }
+#if DEBUG
+ dprintf("Initial memory map:\n");
+ syslinux_dump_memmap(stdout, mmap);
+#endif
+
+ return 0;
+}
+
+struct multiboot_header *map_image(void *ptr, size_t len)
+{
+ struct multiboot_header *mbh;
+ int mbh_len;
+ char *cptr = ptr;
+ Elf32_Ehdr *eh = ptr;
+ Elf32_Phdr *ph;
+ Elf32_Shdr *sh;
+ unsigned int i, mbh_offset;
+ uint32_t bad_flags;
+
+ /*
+ * Search for the multiboot header...
+ */
+ mbh_len = 0;
+ for (mbh_offset = 0; mbh_offset < MULTIBOOT_SEARCH; mbh_offset += 4) {
+ mbh = (struct multiboot_header *)((char *)ptr + mbh_offset);
+ if (mbh->magic != MULTIBOOT_MAGIC)
+ continue;
+ if (mbh->magic + mbh->flags + mbh->checksum)
+ continue;
+ if (mbh->flags & MULTIBOOT_VIDEO_MODE)
+ mbh_len = 48;
+ else if (mbh->flags & MULTIBOOT_AOUT_KLUDGE)
+ mbh_len = 32;
+ else
+ mbh_len = 12;
+
+ if (mbh_offset + mbh_len > len)
+ mbh_len = 0; /* Invalid... */
+ else
+ break; /* Found something... */
+ }
+
+ if (mbh_len) {
+ bad_flags = mbh->flags & MULTIBOOT_UNSUPPORTED;
+ if (bad_flags) {
+ printf("Unsupported Multiboot flags set: %#x\n", bad_flags);
+ return NULL;
+ }
+ }
+
+ if (len < sizeof(Elf32_Ehdr) ||
+ memcmp(eh->e_ident, "\x7f" "ELF\1\1\1", 6) ||
+ (eh->e_machine != EM_386 && eh->e_machine != EM_486 &&
+ eh->e_machine != EM_X86_64) ||
+ eh->e_version != EV_CURRENT ||
+ eh->e_ehsize < sizeof(Elf32_Ehdr) || eh->e_ehsize >= len ||
+ eh->e_phentsize < sizeof(Elf32_Phdr) ||
+ !eh->e_phnum || eh->e_phoff + eh->e_phentsize * eh->e_phnum > len)
+ eh = NULL; /* No valid ELF header found */
+
+ /* Is this a Solaris kernel? */
+ if (!set.solaris && eh && kernel_is_solaris(eh))
+ opt.solaris = true;
+
+ /*
+ * Note: the Multiboot Specification implies that AOUT_KLUDGE should
+ * have precedence over the ELF header. However, Grub disagrees, and
+ * Grub is "the reference bootloader" for the Multiboot Specification.
+ * This is insane, since it makes the AOUT_KLUDGE bit functionally
+ * useless, but at least Solaris apparently depends on this behavior.
+ */
+ if (eh && !(opt.aout && mbh_len && (mbh->flags & MULTIBOOT_AOUT_KLUDGE))) {
+ regs.eip = eh->e_entry; /* Can be overridden further down... */
+
+ ph = (Elf32_Phdr *) (cptr + eh->e_phoff);
+
+ for (i = 0; i < eh->e_phnum; i++) {
+ if (ph->p_type == PT_LOAD || ph->p_type == PT_PHDR) {
+ /*
+ * This loads at p_paddr, which matches Grub. However, if
+ * e_entry falls within the p_vaddr range of this PHDR, then
+ * adjust it to match the p_paddr range... this is how Grub
+ * behaves, so it's by definition correct (it doesn't have to
+ * make sense...)
+ */
+ addr_t addr = ph->p_paddr;
+ addr_t msize = ph->p_memsz;
+ addr_t dsize = min(msize, ph->p_filesz);
+
+ if (eh->e_entry >= ph->p_vaddr
+ && eh->e_entry < ph->p_vaddr + msize)
+ regs.eip = eh->e_entry + (ph->p_paddr - ph->p_vaddr);
+
+ dprintf("Segment at 0x%08x data 0x%08x len 0x%08x\n",
+ addr, dsize, msize);
+
+ if (syslinux_memmap_type(amap, addr, msize) != SMT_FREE) {
+ printf
+ ("Memory segment at 0x%08x (len 0x%08x) is unavailable\n",
+ addr, msize);
+ return NULL; /* Memory region unavailable */
+ }
+
+ /* Mark this region as allocated in the available map */
+ if (syslinux_add_memmap(&amap, addr, msize, SMT_ALLOC)) {
+ error("Overlapping segments found in ELF header\n");
+ return NULL;
+ }
+
+ if (ph->p_filesz) {
+ /* Data present region. Create a move entry for it. */
+ if (syslinux_add_movelist
+ (&ml, addr, (addr_t) cptr + ph->p_offset, dsize)) {
+ error("Failed to map PHDR data\n");
+ return NULL;
+ }
+ }
+ if (msize > dsize) {
+ /* Zero-filled region. Mark as a zero region in the memory map. */
+ if (syslinux_add_memmap
+ (&mmap, addr + dsize, msize - dsize, SMT_ZERO)) {
+ error("Failed to map PHDR zero region\n");
+ return NULL;
+ }
+ }
+ if (addr + msize > mboot_high_water_mark)
+ mboot_high_water_mark = addr + msize;
+ } else {
+ /* Ignore this program header */
+ }
+
+ ph = (Elf32_Phdr *) ((char *)ph + eh->e_phentsize);
+ }
+
+ /* Load the ELF symbol table */
+ if (eh->e_shoff) {
+ addr_t addr, len;
+
+ sh = (Elf32_Shdr *) ((char *)eh + eh->e_shoff);
+
+ len = eh->e_shentsize * eh->e_shnum;
+ /*
+ * Align this, but don't pad -- in general this means a bunch of
+ * smaller sections gets packed into a single page.
+ */
+ addr = map_data(sh, len, 4096, MAP_HIGH | MAP_NOPAD);
+ if (!addr) {
+ error("Failed to map symbol table\n");
+ return NULL;
+ }
+
+ mbinfo.flags |= MB_INFO_ELF_SHDR;
+ mbinfo.syms.e.addr = addr;
+ mbinfo.syms.e.num = eh->e_shnum;
+ mbinfo.syms.e.size = eh->e_shentsize;
+ mbinfo.syms.e.shndx = eh->e_shstrndx;
+
+ for (i = 0; i < eh->e_shnum; i++) {
+ addr_t align;
+
+ if (!sh[i].sh_size)
+ continue; /* Empty section */
+ if (sh[i].sh_flags & SHF_ALLOC)
+ continue; /* SHF_ALLOC sections should have PHDRs */
+
+ align = sh[i].sh_addralign ? sh[i].sh_addralign : 0;
+ addr = map_data((char *)ptr + sh[i].sh_offset, sh[i].sh_size,
+ align, MAP_HIGH);
+ if (!addr) {
+ error("Failed to map symbol section\n");
+ return NULL;
+ }
+ sh[i].sh_addr = addr;
+ }
+ }
+ } else if (mbh_len && (mbh->flags & MULTIBOOT_AOUT_KLUDGE)) {
+ /*
+ * a.out kludge thing...
+ */
+ char *data_ptr;
+ addr_t data_len, bss_len;
+ addr_t bss_addr;
+
+ regs.eip = mbh->entry_addr;
+
+ data_ptr = (char *)mbh - (mbh->header_addr - mbh->load_addr);
+
+ if (mbh->load_end_addr)
+ data_len = mbh->load_end_addr - mbh->load_addr;
+ else
+ data_len = len - mbh_offset + (mbh->header_addr - mbh->load_addr);
+
+ bss_addr = mbh->load_addr + data_len;
+
+ if (mbh->bss_end_addr)
+ bss_len = mbh->bss_end_addr - mbh->load_end_addr;
+ else
+ bss_len = 0;
+
+ if (syslinux_memmap_type(amap, mbh->load_addr, data_len + bss_len)
+ != SMT_FREE) {
+ printf("Memory segment at 0x%08x (len 0x%08x) is unavailable\n",
+ mbh->load_addr, data_len + bss_len);
+ return NULL; /* Memory region unavailable */
+ }
+ if (syslinux_add_memmap(&amap, mbh->load_addr,
+ data_len + bss_len, SMT_ALLOC)) {
+ error("Failed to claim a.out address space!\n");
+ return NULL;
+ }
+ if (data_len)
+ if (syslinux_add_movelist(&ml, mbh->load_addr, (addr_t) data_ptr,
+ data_len)) {
+ error("Failed to map a.out data\n");
+ return NULL;
+ }
+ if (bss_len)
+ if (syslinux_add_memmap
+ (&mmap, bss_addr, bss_len, SMT_ZERO)) {
+ error("Failed to map a.out bss\n");
+ return NULL;
+ }
+ if (bss_addr + bss_len > mboot_high_water_mark)
+ mboot_high_water_mark = bss_addr + bss_len;
+ } else {
+ error
+ ("Invalid Multiboot image: neither ELF header nor a.out kludge found\n");
+ return NULL;
+ }
+
+ return mbh;
+}
+
+/*
+ * Set up a stack. This isn't actually required by the spec, but it seems
+ * like a prudent thing to do. Also, put enough zeros at the top of the
+ * stack that something that looks for an ELF invocation record will know
+ * there isn't one.
+ */
+static void mboot_map_stack(void)
+{
+ addr_t start, len;
+
+ if (syslinux_memmap_largest(amap, SMT_FREE, &start, &len) || len < 64)
+ return; /* Not much we can do, here... */
+
+ regs.esp = (start + len - 32) & ~15;
+ dprintf("Mapping stack at 0x%08x\n", regs.esp);
+ syslinux_add_memmap(&mmap, regs.esp, 32, SMT_ZERO);
+}
+
+void mboot_run(int bootflags)
+{
+ mboot_map_stack();
+
+ dprintf("Running, eip = 0x%08x, ebx = 0x%08x\n", regs.eip, regs.ebx);
+
+ regs.eax = MULTIBOOT_VALID;
+ syslinux_shuffle_boot_pm(ml, mmap, bootflags, &regs);
+}
generated by cgit v1.2.3-55-g7522 (git 2.39.0) at 2024-05-17 14:42:31 +0200