Initial revision

2002-12-27 08:53:07 +00:00 · 2002-12-27 08:53:07 +00:00 · 6a161fa938
commit 6a161fa938
80 changed files with 23264 additions and 0 deletions
--- a/kern/i386/dl.c
+++ b/kern/i386/dl.c
@ -0,0 +1,126 @@
+/* dl-386.c - arch-dependent part of loadable module support */
+/*
+ *  PUPA  --  Preliminary Universal Programming Architecture for GRUB
+ *  Copyright (C) 2002 Yoshinori K. Okuji <okuji@enbug.org>
+ *
+ *  PUPA 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
+ *  (at your option) 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 PUPA; if not, write to the Free Software
+ *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <pupa/dl.h>
+#include <pupa/elf.h>
+#include <pupa/misc.h>
+#include <pupa/err.h>
+
+/* Check if EHDR is a valid ELF header.  */
+int
+pupa_arch_dl_check_header (void *ehdr, unsigned size)
+{
+  Elf32_Ehdr *e = ehdr;
+
+  /* Check the header size.  */
+  if (size < sizeof (Elf32_Ehdr))
+    return 0;
+
+  /* Check the magic numbers.  */
+  if (e->e_ident[EI_MAG0] != ELFMAG0
+      || e->e_ident[EI_MAG1] != ELFMAG1
+      || e->e_ident[EI_MAG2] != ELFMAG2
+      || e->e_ident[EI_MAG3] != ELFMAG3
+      || e->e_version != EV_CURRENT
+      || e->e_ident[EI_CLASS] != ELFCLASS32
+      || e->e_ident[EI_DATA] != ELFDATA2LSB
+      || e->e_machine != EM_386
+      || e->e_type != ET_REL)
+    return 0;
+
+  /* Make sure that every section is within the core.  */
+  if (size < e->e_shoff + e->e_shentsize * e->e_shnum)
+    return 0;
+
+  return 1;
+}
+
+/* Relocate symbols.  */
+pupa_err_t
+pupa_arch_dl_relocate_symbols (pupa_dl_t mod, void *ehdr)
+{
+  Elf32_Ehdr *e = ehdr;
+  Elf32_Shdr *s;
+  Elf32_Sym *symtab;
+  Elf32_Word entsize;
+  unsigned i;
+
+  /* Find a symbol table.  */
+  for (i = 0, s = (Elf32_Shdr *) ((char *) e + e->e_shoff);
+       i < e->e_shnum;
+       i++, s = (Elf32_Shdr *) ((char *) s + e->e_shentsize))
+    if (s->sh_type == SHT_SYMTAB)
+      break;
+
+  if (i == e->e_shnum)
+    return pupa_error (PUPA_ERR_BAD_MODULE, "no symtab found");
+  
+  symtab = (Elf32_Sym *) ((char *) e + s->sh_offset);
+  entsize = s->sh_entsize;
+
+  for (i = 0, s = (Elf32_Shdr *) ((char *) e + e->e_shoff);
+       i < e->e_shnum;
+       i++, s = (Elf32_Shdr *) ((char *) s + e->e_shentsize))
+    if (s->sh_type == SHT_REL)
+      {
+	pupa_dl_segment_t seg;
+
+	/* Find the target segment.  */
+	for (seg = mod->segment; seg; seg = seg->next)
+	  if (seg->section == s->sh_info)
+	    break;
+
+	if (seg)
+	  {
+	    Elf32_Rel *rel, *max;
+	    
+	    for (rel = (Elf32_Rel *) ((char *) e + s->sh_offset),
+		   max = rel + s->sh_size / s->sh_entsize;
+		 rel < max;
+		 rel++)
+	      {
+		Elf32_Word *addr;
+		Elf32_Sym *sym;
+		
+		if (seg->size < rel->r_offset)
+		  return pupa_error (PUPA_ERR_BAD_MODULE,
+				     "reloc offset is out of the segment");
+		
+		addr = (Elf32_Word *) ((char *) seg->addr + rel->r_offset);
+		sym = (Elf32_Sym *) ((char *) symtab
+				     + entsize * ELF32_R_SYM (rel->r_info));
+		
+		switch (ELF32_R_TYPE (rel->r_info))
+		  {
+		  case R_386_32:
+		    *addr += sym->st_value;
+		    break;
+
+		  case R_386_PC32:
+		    *addr += (sym->st_value - (Elf32_Word) seg->addr
+			      - rel->r_offset);
+		    break;
+		  }
+	      }
+	  }
+      }
+
+  return PUPA_ERR_NONE;
+}