Reworked libelf to support relocation

Split elf.c into elf32.c and elf64.c for better readability. Added relocation
code to libelf for 64-bit ELF images, modified the Paflof Makefile to link
the executable with relocation information and load Paflof now to the upper
end of the memory.

Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>

1 files changed, 72 insertions, 2 deletions

diff --git a/include/libelf.h b/include/libelf.h
index 905c76b..7407cf3 100644
--- a/include/libelf.h
+++ b/include/libelf.h
@@ -1,5 +1,5 @@
 /******************************************************************************
- * Copyright (c) 2004, 2008 IBM Corporation
+ * Copyright (c) 2004, 2011 IBM Corporation
  * All rights reserved.
  * This program and the accompanying materials
  * are made available under the terms of the BSD License
@@ -10,9 +10,79 @@
  *     IBM Corporation - initial implementation
  *****************************************************************************/
 
+/*
+ * ELF loader library
+ */
+
 #ifndef __LIBELF_H
 #define __LIBELF_H
 
-int load_elf_file(unsigned long *, unsigned long *);
+#include <stdint.h>
+
+/* ELF object file types */
+#define ET_NONE		0	/* No file type */
+#define ET_REL		1	/* Relocatable file */
+#define ET_EXEC		2	/* Executable file */
+#define ET_DYN		3	/* Shared object file */
+#define ET_CORE		4	/* Core file */
+
+/* Generic ELF header */
+struct ehdr {
+	uint32_t ei_ident;
+	uint8_t ei_class;
+	uint8_t ei_data;
+	uint8_t ei_version;
+	uint8_t ei_pad[9];
+	uint16_t e_type;
+	uint16_t e_machine;
+	uint32_t e_version;
+};
+
+/* Section types (sh_type) */
+#define SHT_NULL	0	/* Unused section header */
+#define SHT_PROGBITS	1	/* Information defined by the program */
+#define SHT_SYMTAB	2	/* Linker symbol table */
+#define SHT_STRTAB	3	/* String table */
+#define SHT_RELA	4	/* "Rela" type relocation entries */
+#define SHT_HASH	5	/* Symbol hash table */
+#define SHT_DYNAMIC	6	/* Dynamic linking tables */
+#define SHT_NOTE	7	/* Note information */
+#define SHT_NOBITS	8	/* Uninitialized space */
+#define SHT_REL 	9	/* "Rel" type relocation entries */
+#define SHT_SHLIB	10	/* Reserved */
+#define SHT_DYNSYM	11	/* Dynamic loader symbol table */
+
+/* Section attributs (sh_flags) */
+#define SHF_WRITE	0x1
+#define SHF_ALLOC	0x2
+#define SHF_EXECINSTR	0x4
+
+/* Segment types (p_type) */
+#define PT_NULL 	0	/* Unused entry */
+#define PT_LOAD 	1	/* Loadable segment */
+#define PT_DYNAMIC	2	/* Dynamic linking tables */
+#define PT_INTERP	3	/* Program interpreter path name */
+#define PT_NOTE 	4	/* Note sections */
+
+
+int elf_load_file(void *file_addr, unsigned long *entry,
+                  int (*pre_load)(void*, long),
+                  void (*post_load)(void*, long));
+int elf_load_file_to_addr(void *file_addr, void *addr, unsigned long *entry,
+                          int (*pre_load)(void*, long),
+                          void (*post_load)(void*, long));
+
+unsigned int elf_load_segments32(void *file_addr, signed long offset,
+                                 int (*pre_load)(void*, long),
+                                 void (*post_load)(void*, long));
+unsigned long elf_load_segments64(void *file_addr, signed long offset,
+                                  int (*pre_load)(void*, long),
+                                  void (*post_load)(void*, long));
+
+long elf_get_base_addr(void *file_addr);
+long elf_get_base_addr32(void *file_addr);
+long elf_get_base_addr64(void *file_addr);
+
+void elf_relocate64(void *file_addr, signed long offset);
 
 #endif				/* __LIBELF_H */