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-rw-r--r--fs/binfmt_em86.c115
1 files changed, 115 insertions, 0 deletions
diff --git a/fs/binfmt_em86.c b/fs/binfmt_em86.c
new file mode 100644
index 0000000..1f2d1ad
--- /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");
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