[PATCH] binfmt_som

SOM is the file format used for HPUX binaries.

fs/Makefile

@@ -29,6 +29,7 @@ obj-$(CONFIG_BINFMT_MISC)	+= binfmt_misc.o
 obj-y				+= binfmt_script.o
 
 obj-$(CONFIG_BINFMT_ELF)	+= binfmt_elf.o
+obj-$(CONFIG_BINFMT_SOM)	+= binfmt_som.o
 
 obj-$(CONFIG_QUOTA)		+= dquot.o
 obj-$(CONFIG_QFMT_V1)		+= quota_v1.o

fs/binfmt_som.c

+/*
+ * linux/fs/binfmt_som.c
+ *
+ * These are the functions used to load SOM format executables as used
+ * by HP-UX.  
+ *
+ * Copyright 1999 Matthew Wilcox <willy@bofh.ai>
+ * based on binfmt_elf which is
+ * Copyright 1993, 1994: Eric Youngdale (ericy@cais.com).
+ */
+
+#include <linux/module.h>
+
+#include <linux/fs.h>
+#include <linux/stat.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/mman.h>
+#include <linux/errno.h>
+#include <linux/signal.h>
+#include <linux/binfmts.h>
+#include <linux/som.h>
+#include <linux/string.h>
+#include <linux/file.h>
+#include <linux/fcntl.h>
+#include <linux/ptrace.h>
+#include <linux/slab.h>
+#include <linux/shm.h>
+#include <linux/personality.h>
+#include <linux/init.h>
+
+#include <asm/uaccess.h>
+#include <asm/pgtable.h>
+
+#include <linux/config.h>
+
+#include <linux/elf.h>
+
+static int load_som_binary(struct linux_binprm * bprm, struct pt_regs * regs);
+static int load_som_library(struct file *);
+
+/*
+ * If we don't support core dumping, then supply a NULL so we
+ * don't even try.
+ */
+#if 0
+static int som_core_dump(long signr, struct pt_regs * regs);
+#else
+#define som_core_dump	NULL
+#endif
+
+#define SOM_PAGESTART(_v) ((_v) & ~(unsigned long)(SOM_PAGESIZE-1))
+#define SOM_PAGEOFFSET(_v) ((_v) & (SOM_PAGESIZE-1))
+#define SOM_PAGEALIGN(_v) (((_v) + SOM_PAGESIZE - 1) & ~(SOM_PAGESIZE - 1))
+
+static struct linux_binfmt som_format = {
+	NULL, THIS_MODULE, load_som_binary, load_som_library, som_core_dump, SOM_PAGESIZE
+};
+
+/*
+ * create_som_tables() parses the env- and arg-strings in new user
+ * memory and creates the pointer tables from them, and puts their
+ * addresses on the "stack", returning the new stack pointer value.
+ */
+static void create_som_tables(struct linux_binprm *bprm)
+{
+	char **argv, **envp;
+	int argc = bprm->argc;
+	int envc = bprm->envc;
+	unsigned long p;
+	unsigned long *sp;
+
+	/* Word-align the stack pointer */
+	sp = (unsigned long *)((bprm->p + 3) & ~3);
+
+	envp = (char **) sp;
+	sp += envc + 1;
+	argv = (char **) sp;
+	sp += argc + 1;
+
+	__put_user((unsigned long) envp,++sp);
+	__put_user((unsigned long) argv,++sp);
+
+	__put_user(argc, ++sp);
+
+	bprm->p = (unsigned long) sp;
+
+	p = current->mm->arg_start;
+	while (argc-- > 0) {
+		__put_user((char *)p,argv++);
+		p += strlen_user((char *)p);
+	}
+	__put_user(NULL, argv);
+	current->mm->arg_end = current->mm->env_start = p;
+	while (envc-- > 0) {
+		__put_user((char *)p,envp++);
+		p += strlen_user((char *)p);
+	}
+	__put_user(NULL, envp);
+	current->mm->env_end = p;
+}
+
+static int check_som_header(struct som_hdr *som_ex)
+{
+	int *buf = (int *)som_ex;
+	int i, ck;
+
+	if (som_ex->system_id != SOM_SID_PARISC_1_0 &&
+	    som_ex->system_id != SOM_SID_PARISC_1_1 &&
+	    som_ex->system_id != SOM_SID_PARISC_2_0)
+		return -ENOEXEC;
+
+	if (som_ex->a_magic != SOM_EXEC_NONSHARE &&
+	    som_ex->a_magic != SOM_EXEC_SHARE &&
+	    som_ex->a_magic != SOM_EXEC_DEMAND)
+		return -ENOEXEC;
+
+	if (som_ex->version_id != SOM_ID_OLD &&
+	    som_ex->version_id != SOM_ID_NEW)
+		return -ENOEXEC;
+
+	ck = 0;
+	for (i=0; i<32; i++)
+		ck ^= buf[i];
+	if (ck != 0)
+		return -ENOEXEC;
+
+	return 0;
+}
+
+static int map_som_binary(struct file *file,
+		const struct som_exec_auxhdr *hpuxhdr)
+{
+	unsigned long code_start, code_size, data_start, data_size;
+	unsigned long bss_start, som_brk;
+	int retval;
+	int prot = PROT_READ | PROT_EXEC;
+	int flags = MAP_FIXED|MAP_PRIVATE|MAP_DENYWRITE|MAP_EXECUTABLE;
+
+	mm_segment_t old_fs = get_fs();
+	set_fs(get_ds());
+
+	code_start = SOM_PAGESTART(hpuxhdr->exec_tmem);
+	code_size = SOM_PAGEALIGN(hpuxhdr->exec_tsize);
+	current->mm->start_code = code_start;
+	current->mm->end_code = code_start + code_size;
+	down_write(&current->mm->mmap_sem);
+	retval = do_mmap(file, code_start, code_size, prot,
+			flags, SOM_PAGESTART(hpuxhdr->exec_tfile));
+	up_write(&current->mm->mmap_sem);
+	if (retval < 0 && retval > -1024)
+		goto out;
+
+	data_start = SOM_PAGESTART(hpuxhdr->exec_dmem);
+	data_size = SOM_PAGEALIGN(hpuxhdr->exec_dsize);
+	current->mm->start_data = data_start;
+	current->mm->end_data = bss_start = data_start + data_size;
+	down_write(&current->mm->mmap_sem);
+	retval = do_mmap(file, data_start, data_size,
+			prot | PROT_WRITE, flags,
+			SOM_PAGESTART(hpuxhdr->exec_dfile));
+	up_write(&current->mm->mmap_sem);
+	if (retval < 0 && retval > -1024)
+		goto out;
+
+	som_brk = bss_start + SOM_PAGEALIGN(hpuxhdr->exec_bsize);
+	current->mm->start_brk = current->mm->brk = som_brk;
+	down_write(&current->mm->mmap_sem);
+	retval = do_mmap(NULL, bss_start, som_brk - bss_start,
+			prot | PROT_WRITE, MAP_FIXED | MAP_PRIVATE, 0);
+	up_write(&current->mm->mmap_sem);
+	if (retval > 0 || retval < -1024)
+		retval = 0;
+out:
+	set_fs(old_fs);
+	return retval;
+}
+
+
+/*
+ * These are the functions used to load SOM executables and shared
+ * libraries.  There is no binary dependent code anywhere else.
+ */
+
+static inline int
+do_load_som_binary(struct linux_binprm * bprm, struct pt_regs * regs)
+{
+	int som_exec_fileno;
+	int retval;
+	unsigned int size;
+	unsigned long som_entry;
+	struct som_hdr *som_ex;
+	struct som_exec_auxhdr *hpuxhdr;
+
+	/* Get the exec-header */
+	som_ex = (struct som_hdr *) bprm->buf;
+
+	retval = check_som_header(som_ex);
+	if (retval != 0)
+		goto out;
+
+	/* Now read in the auxiliary header information */
+
+	retval = -ENOMEM;
+	size = som_ex->aux_header_size;
+	if (size > SOM_PAGESIZE)
+		goto out;
+	hpuxhdr = (struct som_exec_auxhdr *) kmalloc(size, GFP_KERNEL);
+	if (!hpuxhdr)
+		goto out;
+
+	retval = kernel_read(bprm->file, som_ex->aux_header_location,
+			(char *) hpuxhdr, size);
+	if (retval < 0)
+		goto out_free;
+
+	retval = get_unused_fd();
+	if (retval < 0)
+		goto out_free;
+	get_file(bprm->file);
+	fd_install(som_exec_fileno = retval, bprm->file);
+
+	/* Flush all traces of the currently running executable */
+	retval = flush_old_exec(bprm);
+	if (retval)
+		goto out_free;
+
+	/* OK, This is the point of no return */
+	current->flags &= ~PF_FORKNOEXEC;
+	current->personality = PER_HPUX;
+
+	/* Set the task size for HP-UX processes such that
+	 * the gateway page is outside the address space.
+	 * This can be fixed later, but for now, this is much
+	 * easier.
+	 */
+
+	current->thread.task_size = 0xc0000000;
+
+	/* Set map base to allow enough room for hp-ux heap growth */
+
+	current->thread.map_base = 0x80000000;
+
+	retval = map_som_binary(bprm->file, hpuxhdr);
+	if (retval < 0)
+		goto out_free;
+
+	som_entry = hpuxhdr->exec_entry;
+	kfree(hpuxhdr);
+
+	set_binfmt(&som_format);
+	compute_creds(bprm);
+	setup_arg_pages(bprm);
+
+	create_som_tables(bprm);
+
+	current->mm->start_stack = bprm->p;
+	current->mm->rss = 0;
+
+#if 0
+	printk("(start_brk) %08lx\n" , (unsigned long) current->mm->start_brk);
+	printk("(end_code) %08lx\n" , (unsigned long) current->mm->end_code);
+	printk("(start_code) %08lx\n" , (unsigned long) current->mm->start_code);
+	printk("(end_data) %08lx\n" , (unsigned long) current->mm->end_data);
+	printk("(start_stack) %08lx\n" , (unsigned long) current->mm->start_stack);
+	printk("(brk) %08lx\n" , (unsigned long) current->mm->brk);
+#endif
+
+	map_hpux_gateway_page(current,current->mm);
+
+	start_thread_som(regs, som_entry, bprm->p);
+	if (current->ptrace & PT_PTRACED)
+		send_sig(SIGTRAP, current, 0);
+	return 0;
+
+	/* error cleanup */
+out_free:
+	kfree(hpuxhdr);
+out:
+	return retval;
+}
+
+static int
+load_som_binary(struct linux_binprm * bprm, struct pt_regs * regs)
+{
+	int retval;
+
+	MOD_INC_USE_COUNT;
+	retval = do_load_som_binary(bprm, regs);
+	MOD_DEC_USE_COUNT;
+	return retval;
+}
+
+static inline int
+do_load_som_library(struct file *f)
+{
+/* No lib support in SOM yet.  gizza chance.. */
+	return -ENOEXEC;
+}
+
+static int load_som_library(struct file *f)
+{
+	int retval;
+
+	MOD_INC_USE_COUNT;
+	retval = do_load_som_library(f);
+	MOD_DEC_USE_COUNT;
+	return retval;
+}
+
+	/* Install the SOM loader.
+	 * N.B. We *rely* on the table being the right size with the
+	 * right number of free slots...
+	 */
+
+static int __init init_som_binfmt(void)
+{
+	return register_binfmt(&som_format);
+}
+
+static void __exit exit_som_binfmt(void)
+{
+	/* Remove the SOM loader. */
+	unregister_binfmt(&som_format);
+}
+
+module_init(init_som_binfmt);
+module_exit(exit_som_binfmt);
+

include/linux/som.h

+#ifndef _LINUX_SOM_H
+#define _LINUX_SOM_H
+
+/* File format definition for SOM executables / shared libraries */
+
+/* we need struct timespec */
+#include <linux/time.h>
+
+#define SOM_PAGESIZE 4096
+
+/* this is the SOM header */
+struct som_hdr {
+	short		system_id;		/* magic number - system */
+	short		a_magic;		/* magic number - file type */
+	unsigned int	version_id;		/* versiod ID: YYMMDDHH */
+	struct timespec	file_time;		/* system clock */
+	unsigned int	entry_space;		/* space for entry point */
+	unsigned int	entry_subspace;		/* subspace for entry point */
+	unsigned int	entry_offset;		/* offset of entry point */
+	unsigned int	aux_header_location;	/* auxiliary header location */
+	unsigned int	aux_header_size;	/* auxiliary header size */
+	unsigned int	som_length;		/* length of entire SOM */
+	unsigned int	presumed_dp;		/* compiler's DP value */
+	unsigned int	space_location;		/* space dictionary location */
+	unsigned int	space_total;		/* number of space entries */
+	unsigned int	subspace_location;	/* subspace entries location */
+	unsigned int	subspace_total;		/* number of subspace entries */
+	unsigned int	loader_fixup_location;	/* MPE/iX loader fixup */
+	unsigned int	loader_fixup_total;	/* number of fixup records */
+	unsigned int	space_strings_location;	/* (sub)space names */
+	unsigned int	space_strings_size;	/* size of strings area */
+	unsigned int	init_array_location;	/* reserved */
+	unsigned int	init_array_total;	/* reserved */
+	unsigned int	compiler_location;	/* module dictionary */
+	unsigned int	compiler_total;		/* number of modules */
+	unsigned int	symbol_location;	/* symbol dictionary */
+	unsigned int	symbol_total;		/* number of symbols */
+	unsigned int	fixup_request_location;	/* fixup requests */
+	unsigned int	fixup_request_total;	/* number of fixup requests */
+	unsigned int	symbol_strings_location;/* module & symbol names area */
+	unsigned int	symbol_strings_size;	/* size of strings area */
+	unsigned int	unloadable_sp_location;	/* unloadable spaces location */
+	unsigned int	unloadable_sp_size;	/* size of data */
+	unsigned int	checksum;
+};
+
+/* values for system_id */
+
+#define SOM_SID_PARISC_1_0	0x020b
+#define SOM_SID_PARISC_1_1	0x0210
+#define SOM_SID_PARISC_2_0	0x0214
+
+/* values for a_magic */
+
+#define SOM_LIB_EXEC		0x0104
+#define SOM_RELOCATABLE		0x0106
+#define SOM_EXEC_NONSHARE	0x0107
+#define SOM_EXEC_SHARE		0x0108
+#define SOM_EXEC_DEMAND		0x010B
+#define SOM_LIB_DYN		0x010D
+#define SOM_LIB_SHARE		0x010E
+#define SOM_LIB_RELOC		0x0619
+
+/* values for version_id.  Decimal not hex, yes.  Grr. */
+
+#define SOM_ID_OLD		85082112
+#define SOM_ID_NEW		87102412
+
+struct aux_id {
+	unsigned int	mandatory :1;	/* the linker must understand this */
+	unsigned int	copy	  :1;	/* Must be copied by the linker */
+	unsigned int	append	  :1;	/* Must be merged by the linker */
+	unsigned int	ignore	  :1;	/* Discard section if unknown */
+	unsigned int	reserved  :12;
+	unsigned int	type	  :16;	/* Header type */
+	unsigned int	length;		/* length of _following_ data */
+};
+
+/* The Exec Auxiliary Header.  Called The HP-UX Header within HP apparently. */
+struct som_exec_auxhdr {
+	struct aux_id	som_auxhdr;
+	int		exec_tsize;	/* Text size in bytes */
+	int		exec_tmem;	/* Address to load text at */
+	int		exec_tfile;	/* Location of text in file */
+	int		exec_dsize;	/* Data size in bytes */
+	int		exec_dmem;	/* Address to load data at */
+	int		exec_dfile;	/* Location of data in file */
+	int		exec_bsize;	/* Uninitialised data (bss) */
+	int		exec_entry;	/* Address to start executing */
+	int		exec_flags;	/* loader flags */
+	int		exec_bfill;	/* initialisation value for bss */
+};
+
+/* Oh, the things people do to avoid casts.  Shame it'll break with gcc's
+ * new aliasing rules really.
+ */
+union name_pt {
+	char *		n_name;
+	unsigned int	n_strx;
+};
+
+/* The Space Dictionary */
+struct space_dictionary_record {
+	union name_pt	name;			/* index to subspace name */
+	unsigned int	is_loadable	:1;	/* loadable */
+	unsigned int	is_defined	:1;	/* defined within file */
+	unsigned int	is_private	:1;	/* not sharable */
+	unsigned int	has_intermediate_code :1; /* contains intermediate code */
+	unsigned int	is_tspecific	:1;	/* thread specific */
+	unsigned int	reserved	:11;	/* for future expansion */
+	unsigned int	sort_key	:8;	/* for linker */
+	unsigned int	reserved2	:8;	/* for future expansion */
+
+	int		space_number;		/* index */
+	int		subspace_index;		/* index into subspace dict */
+	unsigned int	subspace_quantity;	/* number of subspaces */
+	int		loader_fix_index;	/* for loader */
+	unsigned int	loader_fix_quantity;	/* for loader */
+	int		init_pointer_index;	/* data pointer array index */
+	unsigned int	init_pointer_quantity;	/* number of data pointers */
+};
+
+/* The Subspace Dictionary */
+struct subspace_dictionary_record {
+	int		space_index;
+	unsigned int	access_control_bits :7;
+	unsigned int	memory_resident	:1;
+	unsigned int	dup_common	:1;
+	unsigned int	is_common	:1;
+	unsigned int	quadrant	:2;
+	unsigned int	initially_frozen :1;
+	unsigned int	is_first	:1;
+	unsigned int	code_only	:1;
+	unsigned int	sort_key	:8;
+	unsigned int	replicate_init	:1;
+	unsigned int	continuation	:1;
+	unsigned int	is_tspecific	:1;
+	unsigned int	is_comdat	:1;
+	unsigned int	reserved	:4;
+
+	int		file_loc_init_value;
+	unsigned int	initialization_length;
+	unsigned int	subspace_start;
+	unsigned int	subspace_length;
+
+	unsigned int	reserved2	:5;
+	unsigned int	alignment	:27;
+
+	union name_pt	name;
+	int		fixup_request_index;
+	unsigned int	fixup_request_quantity;
+};
+
+#endif /* _LINUX_SOM_H */