1 files changed, 115 insertions, 0 deletions

diff --git a/fs/binfmt_em86.c b/fs/binfmt_em86.c
new file mode 100644
index 000000000000..1f2d1ad63319
--- /dev/null
+++ b/fs/binfmt_em86.c
@@ -0,0 +1,115 @@
+/*
+ *  linux/fs/binfmt_em86.c
+ *
+ *  Based on linux/fs/binfmt_script.c
+ *  Copyright (C) 1996  Martin von Löwis
+ *  original #!-checking implemented by tytso.
+ *
+ *  em86 changes Copyright (C) 1997  Jim Paradis
+ */
+
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/stat.h>
+#include <linux/slab.h>
+#include <linux/smp_lock.h>
+#include <linux/binfmts.h>
+#include <linux/elf.h>
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/errno.h>
+
+
+#define EM86_INTERP     "/usr/bin/em86"
+#define EM86_I_NAME     "em86"
+
+static int load_em86(struct linux_binprm *bprm,struct pt_regs *regs)
+{
+        char *interp, *i_name, *i_arg;
+        struct file * file;
+        int retval;
+        struct elfhdr   elf_ex;
+
+        /* Make sure this is a Linux/Intel ELF executable... */
+        elf_ex = *((struct elfhdr *)bprm->buf);
+
+        if (memcmp(elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
+                return  -ENOEXEC;
+
+        /* First of all, some simple consistency checks */
+        if ((elf_ex.e_type != ET_EXEC && elf_ex.e_type != ET_DYN) ||
+                (!((elf_ex.e_machine == EM_386) || (elf_ex.e_machine == EM_486))) ||
+                (!bprm->file->f_op || !bprm->file->f_op->mmap)) {
+                        return -ENOEXEC;
+        }
+
+        bprm->sh_bang++;        /* Well, the bang-shell is implicit... */
+        allow_write_access(bprm->file);
+        fput(bprm->file);
+        bprm->file = NULL;
+
+        /* Unlike in the script case, we don't have to do any hairy
+         * parsing to find our interpreter... it's hardcoded!
+         */
+        interp = EM86_INTERP;
+        i_name = EM86_I_NAME;
+        i_arg = NULL;           /* We reserve the right to add an arg later */
+
+        /*
+         * Splice in (1) the interpreter's name for argv[0]
+         *           (2) (optional) argument to interpreter
+         *           (3) filename of emulated file (replace argv[0])
+         *
+         * This is done in reverse order, because of how the
+         * user environment and arguments are stored.
+         */
+        remove_arg_zero(bprm);
+        retval = copy_strings_kernel(1, &bprm->filename, bprm);
+        if (retval < 0) return retval; 
+        bprm->argc++;
+        if (i_arg) {
+                retval = copy_strings_kernel(1, &i_arg, bprm);
+                if (retval < 0) return retval; 
+                bprm->argc++;
+        }
+        retval = copy_strings_kernel(1, &i_name, bprm);
+        if (retval < 0) return retval;
+        bprm->argc++;
+
+        /*
+         * OK, now restart the process with the interpreter's inode.
+         * Note that we use open_exec() as the name is now in kernel
+         * space, and we don't need to copy it.
+         */
+        file = open_exec(interp);
+        if (IS_ERR(file))
+                return PTR_ERR(file);
+
+        bprm->file = file;
+
+        retval = prepare_binprm(bprm);
+        if (retval < 0)
+                return retval;
+
+        return search_binary_handler(bprm, regs);
+}
+
+static struct linux_binfmt em86_format = {
+        .module         = THIS_MODULE,
+        .load_binary    = load_em86,
+};
+
+static int __init init_em86_binfmt(void)
+{
+        return register_binfmt(&em86_format);
+}
+
+static void __exit exit_em86_binfmt(void)
+{
+        unregister_binfmt(&em86_format);
+}
+
+core_initcall(init_em86_binfmt);
+module_exit(exit_em86_binfmt);
+MODULE_LICENSE("GPL");