Make elfload not use hooks. Opt for flags and iterators instead.

2013-03-02 16:45:57 +01:00 · 2013-03-02 16:45:57 +01:00 · 73bf57e2c8
commit 73bf57e2c8
parent 7f8c105f61
9 changed files with 298 additions and 629 deletions
--- a/grub-core/kern/elfXX.c
+++ b/grub-core/kern/elfXX.c
@ -0,0 +1,144 @@
+int
+grub_elf_is_elfXX (grub_elf_t elf)
+{
+  return elf->ehdr.ehdrXX.e_ident[EI_CLASS] == ELFCLASSXX;
+}
+
+grub_err_t
+grub_elfXX_load_phdrs (grub_elf_t elf)
+{
+  grub_ssize_t phdrs_size;
+
+  if (elf->phdrs)
+    return GRUB_ERR_NONE;
+
+  phdrs_size = elf->ehdr.ehdrXX.e_phnum * elf->ehdr.ehdrXX.e_phentsize;
+
+  grub_dprintf ("elf", "Loading program headers at 0x%llx, size 0x%lx.\n",
+		(unsigned long long) elf->ehdr.ehdrXX.e_phoff,
+		(unsigned long) phdrs_size);
+
+  elf->phdrs = grub_malloc (phdrs_size);
+  if (! elf->phdrs)
+    return grub_errno;
+
+  if ((grub_file_seek (elf->file, elf->ehdr.ehdrXX.e_phoff) == (grub_off_t) -1)
+      || (grub_file_read (elf->file, elf->phdrs, phdrs_size) != phdrs_size))
+    {
+      if (!grub_errno)
+	grub_error (GRUB_ERR_FILE_READ_ERROR, N_("premature end of file %s"),
+		    elf->filename);
+      return grub_errno;
+    }
+
+  return GRUB_ERR_NONE;
+}
+
+/* Calculate the amount of memory spanned by the segments.  */
+grub_size_t
+grub_elfXX_size (grub_elf_t elf,
+		 ElfXX_Addr *base, grub_uintXX_t *max_align)
+{
+  ElfXX_Addr segments_start = (ElfXX_Addr) -1;
+  ElfXX_Addr segments_end = 0;
+  int nr_phdrs = 0;
+  grub_uint32_t curr_align = 1;
+  ElfXX_Phdr *phdr;
+
+  /* Run through the program headers to calculate the total memory size we
+   * should claim.  */
+  FOR_ELFXX_PHDRS (elf, phdr)
+    {
+      /* Only consider loadable segments.  */
+      if (phdr->p_type != PT_LOAD)
+	continue;
+      nr_phdrs++;
+      if (phdr->p_paddr < segments_start)
+	segments_start = phdr->p_paddr;
+      if (phdr->p_paddr + phdr->p_memsz > segments_end)
+	segments_end = phdr->p_paddr + phdr->p_memsz;
+      if (curr_align < phdr->p_align)
+	curr_align = phdr->p_align;
+    }
+
+  if (base)
+    *base = 0;
+
+  if (nr_phdrs == 0)
+    {
+      grub_error (GRUB_ERR_BAD_OS, "no program headers present");
+      return 0;
+    }
+
+  if (segments_end < segments_start)
+    {
+      /* Very bad addresses.  */
+      grub_error (GRUB_ERR_BAD_OS, "bad program header load addresses");
+      return 0;
+    }
+
+  if (base)
+    *base = segments_start;
+  if (max_align)
+    *max_align = curr_align;
+  return segments_end - segments_start;
+}
+
+grub_err_t
+grub_elfXX_load (grub_elf_t elf, const char *filename,
+		 void *load_offset, enum grub_elf_load_flags load_flags,
+		 grub_addr_t *base, grub_size_t *size)
+{
+  grub_addr_t load_base = (grub_addr_t) -1ULL;
+  grub_size_t load_size = 0;
+  ElfXX_Phdr *phdr;
+
+  FOR_ELFXX_PHDRS(elf, phdr)
+  {
+    grub_addr_t load_addr;
+
+    if (phdr->p_type != PT_LOAD && !((load_flags & GRUB_ELF_LOAD_FLAGS_LOAD_PT_DYNAMIC) && phdr->p_type == PT_DYNAMIC))
+      continue;
+
+    load_addr = (grub_addr_t) phdr->p_paddr;
+    if (load_flags & GRUB_ELF_LOAD_FLAGS_28BITS)
+      load_addr &= 0xFFFFFFF;
+    load_addr += (grub_addr_t) load_offset;
+
+    if (load_addr < load_base)
+      load_base = load_addr;
+
+    grub_dprintf ("elf", "Loading segment at 0x%llx, size 0x%llx\n",
+		  (unsigned long long) load_addr,
+		  (unsigned long long) phdr->p_memsz);
+
+    if (grub_file_seek (elf->file, phdr->p_offset) == (grub_off_t) -1)
+      return grub_errno;
+
+    if (phdr->p_filesz)
+      {
+	grub_ssize_t read;
+	read = grub_file_read (elf->file, (void *) load_addr, phdr->p_filesz);
+	if (read != (grub_ssize_t) phdr->p_filesz)
+	  {
+	    if (!grub_errno)
+	      grub_error (GRUB_ERR_FILE_READ_ERROR, N_("premature end of file %s"),
+			  filename);
+	    return grub_errno;
+	  }
+      }
+
+    if (phdr->p_filesz < phdr->p_memsz)
+      grub_memset ((void *) (long) (load_addr + phdr->p_filesz),
+		   0, phdr->p_memsz - phdr->p_filesz);
+
+    load_size += phdr->p_memsz;
+  }
+
+  if (base)
+    *base = load_base;
+  if (size)
+    *size = load_size;
+
+  return grub_errno;
+}