add elf loader to grub boot; doesn't do aseg opening yet (todo!)

diff --git a/grubload/Makefile b/grubload/Makefile
index 971fb5ce2eb312e7b3f6d065c3119841751f32f8..041f09c0b41bff219ccb8443079134ee3f06c57a 100644 (file)
--- a/grubload/Makefile
+++ b/grubload/Makefile
@@ -1,4 +1,4 @@
-OBJS=multiboot_c.o multiboot_asm.o console.o minilib.o
+OBJS=multiboot_c.o multiboot_asm.o console.o minilib.o loader.o

 CC=gcc
 CFLAGS=-nostdlib -I../include -I. -fno-builtin -nostdinc
 
 CC=gcc
 CFLAGS=-nostdlib -I../include -I. -fno-builtin -nostdinc
 

diff --git a/grubload/loader.c b/grubload/loader.c
new file mode 100644 (file)
index 0000000..4ecba2a
--- /dev/null
+++ b/grubload/loader.c
@@ -0,0 +1,49 @@
+#include "minilib.h"
+#include "../include/elf.h"
+
+static const unsigned char elf_ident[4] = { 0x7F, 'E', 'L', 'F' }; 
+
+int load_elf (char * buf, int size) {
+
+       Elf32_Ehdr * elf_hdr = (Elf32_Ehdr *) buf;
+       Elf32_Shdr * elf_sec_hdrs = (Elf32_Shdr *) (buf + elf_hdr->e_shoff);
+
+       /* Sanity check on ELF file */
+       if (memcmp(elf_hdr->e_ident, elf_ident, sizeof(elf_ident))) return -1;
+       if (elf_hdr->e_type != ET_EXEC) return -1;
+       if (elf_hdr->e_machine != EM_386) return -1;
+       if (elf_hdr->e_version != EV_CURRENT) return -1;
+       if (size < sizeof(Elf32_Ehdr)) return -1;
+       if (((char *)&elf_sec_hdrs[elf_hdr->e_shnum]) > (buf + size)) return -1;
+
+       char * string_table = buf + elf_sec_hdrs[elf_hdr->e_shstrndx].sh_offset;
+
+       if (string_table > (buf + size)) return -1;
+
+       int i;
+       for (i = 0; i < elf_hdr->e_shnum; i++) {
+
+               if (elf_sec_hdrs[i].sh_name == SHN_UNDEF) {
+                       continue;
+               }
+
+               char * section_name = string_table + elf_sec_hdrs[i].sh_name;
+
+               if ((elf_sec_hdrs[i].sh_type != SHT_PROGBITS) || !(elf_sec_hdrs[i].sh_flags & SHF_ALLOC)) {
+                       puts("Skipping ");
+                       puts(section_name);
+                       puts("\n");
+                       continue;
+               }
+
+               puts("Loading ");
+               puts(section_name);
+               puts("\n");
+
+               memcpy(elf_sec_hdrs[i].sh_addr,
+                      buf + elf_sec_hdrs[i].sh_offset,
+                      elf_sec_hdrs[i].sh_size);
+       }
+
+       return 0;
+}

diff --git a/grubload/loader.h b/grubload/loader.h
new file mode 100644 (file)
index 0000000..e5d5c52
--- /dev/null
+++ b/grubload/loader.h
@@ -0,0 +1,2 @@
+int load_elf (char * buf, int size) ;
+

diff --git a/grubload/minilib.c b/grubload/minilib.c
index f2ab6629d858238d8fd76b0634e1e06536110c5d..b9813d7992fae94635eafc6fdc02776de76084cc 100644 (file)
--- a/grubload/minilib.c
+++ b/grubload/minilib.c
@@ -20,6 +20,24 @@ void memmove(unsigned char *dest, unsigned char *src, int bytes)
                        *(dest++) = *(src++);
 }
 
                        *(dest++) = *(src++);
 }
 

+int memcmp (unsigned char *a2, unsigned char *a1, int bytes) {
+       while (bytes--)
+       {
+               if (*(a2++) != *(a1++))
+                       return 1;
+       }
+       return 0;
+}
+
+int strcmp (unsigned char *a2, unsigned char *a1) {
+       while (1) {
+               if (*a2 != *a1) return 1;
+               if (*a2 == 0) return 0;
+               a1++;
+               a2++;
+       }
+}
+

 int strlen(char *c)
 {
        int l = 0;
 int strlen(char *c)
 {
        int l = 0;

diff --git a/grubload/minilib.h b/grubload/minilib.h
new file mode 100644 (file)
index 0000000..e0fc16b
--- /dev/null
+++ b/grubload/minilib.h
@@ -0,0 +1,33 @@
+#ifndef __MINILIB_H
+#define __MINILIB_H
+
+#define MINILIB 1
+
+#ifndef __int8_t_defined
+# define __int8_t_defined
+typedef signed char             int8_t;
+typedef short int               int16_t;
+typedef int                     int32_t;
+# if __WORDSIZE == 64
+typedef long int                int64_t;
+# else
+__extension__
+typedef long long int           int64_t;
+# endif
+#endif
+
+/* Unsigned.  */
+typedef unsigned char           uint8_t;
+typedef unsigned short int      uint16_t;
+#ifndef __uint32_t_defined
+typedef unsigned int            uint32_t;
+# define __uint32_t_defined
+#endif
+#if __WORDSIZE == 64
+typedef unsigned long int       uint64_t;
+#else
+__extension__
+typedef unsigned long long int  uint64_t;
+#endif
+
+#endif

diff --git a/grubload/multiboot_c.c b/grubload/multiboot_c.c
index c87b6755634dfab2c8b7b10c669f83ff33f6397d..f87168704fe0be9d15df95afdf03e40012354623 100644 (file)
--- a/grubload/multiboot_c.c
+++ b/grubload/multiboot_c.c
@@ -33,7 +33,8 @@ void c_start(unsigned int magic, struct mb_info *wee)
        puts("Grubptr is: ");
        puthex(*grubptr);
        puts("\n");
        puts("Grubptr is: ");
        puthex(*grubptr);
        puts("\n");

-       
+
+

        for (i = 0; i < wee->mod_cnt; i++)
        {
                puts("Module:\n");
        for (i = 0; i < wee->mod_cnt; i++)
        {
                puts("Module:\n");


@@ -41,6 +42,16 @@ void c_start(unsigned int magic, struct mb_info *wee)
                puts("  Size: "); puthex(wee->mods[i].mod_end - wee->mods[i].mod_start); puts("\n");
                puts("  Name: "); puts(wee->mods[i].mod_string); puts("\n");
        }
                puts("  Size: "); puthex(wee->mods[i].mod_end - wee->mods[i].mod_start); puts("\n");
                puts("  Name: "); puts(wee->mods[i].mod_string); puts("\n");
        }

+
+       if ((wee->mod_cnt != 1) || (strcmp(wee->mods[0].mod_string, "aseg.elf")))
+       {
+               puts("Expected 1 module called aseg.elf.\n");
+               while(1) asm("hlt");
+       }
+
+       load_elf(wee->mods[0].mod_start, wee->mods[0].mod_end - wee->mods[0].mod_start);
+
+

        while (1)
                ;
 }
        while (1)
                ;
 }

diff --git a/include/elf.h b/include/elf.h
index 7240b699cfc5ce1d42d6a5ca191afd3b493aee76..0d5abbd0f72edd850c80994fc2ccc4ed76c28e91 100644 (file)
--- a/include/elf.h
+++ b/include/elf.h
@@ -21,7 +21,9 @@
 #ifndef _ELF_H
 #define        _ELF_H 1
 
 #ifndef _ELF_H
 #define        _ELF_H 1
 

+#ifndef MINILIB

 #include <stdint.h>
 #include <stdint.h>

+#endif

 
 /* Standard ELF types.  */
 
 
 /* Standard ELF types.  */