Below a patch to pre-2.1.45-7 is attached that does the following:
- update binfmt_misc docs (esp. Java section)
- revert some changes to binfmt_misc (well, the 'quickshot'/'fast draw')
- add dput and dget symbols to kernel/ksyms.c to let binfmt_misc compile
as a module
Please apply before 2.1.45
Richard.
diff -u --recursive --new-file pre-linux-2.1.45-6/Documentation/binfmt_misc.txt pre-linux-2.1.45-6x/Documentation/binfmt_misc.txt
--- pre-linux-2.1.45-6/Documentation/binfmt_misc.txt Tue Jul 15 14:29:11 1997
+++ pre-linux-2.1.45-6x/Documentation/binfmt_misc.txt Tue Jul 15 18:23:29 1997
@@ -1,26 +1,26 @@
- Kernel Support for miscellaneous (your favourite) Binary Formats v1.1
- =====================================================================
+ Kernel Support for miscellaneous (your favourite) Binary Formats v1.1
+ =====================================================================
This Kernel feature allows to invoke almost (for restrictions see below) every
-program by simply typing it's name in the shell.
+program by simply typing its name in the shell.
This includes for example compiled Java(TM), Python or Emacs programs.
-To achieve this you must tell binfmt_misc which interpreter has to be invoked with
-which binary. Binfmt_misc recognises the binary-type by matching some bytes at the
-beginning of the file with a magic byte sequence (masking out specified bits) you
-have supplied. Binfmt_misc can also recognise a filename extension (aka .com) and
-optionally strip it off.
+To achieve this you must tell binfmt_misc which interpreter has to be invoked
+with which binary. Binfmt_misc recognises the binary-type by matching some bytes
+at the beginning of the file with a magic byte sequence (masking out specified
+bits) you have supplied. Binfmt_misc can also recognise a filename extension
+(aka .com) and optionally strip it off.
To actually register a new binary type, you have to set up a string looking like
-:name:type:offset:magic:mask:interpreter: (where you can choose the ':' upon your
-needs) and echo it to /proc/sys/fs/binfmt_misc/register.
+:name:type:offset:magic:mask:interpreter: (where you can choose the ':' upon
+your needs) and echo it to /proc/sys/fs/binfmt_misc/register.
Here is what the fields mean:
- 'name' is an identifier string. A new /proc file will be created with this
- this name below /proc/sys/fs/binfmt_misc
+ name below /proc/sys/fs/binfmt_misc
- 'type' is the type of recognition. Give 'M' for magic and 'E' for extension.
- Give the corresponding lowercase letter to let binfmt_misc strip of the
+ Give the corresponding lowercase letter to let binfmt_misc strip off the
filename extension.
- - 'offset' is the offset of the magic/mask in the file counted in bytes. This
+ - 'offset' is the offset of the magic/mask in the file, counted in bytes. This
defaults to 0 if you omit it (i.e. you write ':name:type::magic...')
- 'magic' is the byte sequence binfmt_misc is matching for. The magic string
may contain hex-encoded characters like \x0a or \xA4. In a shell environment
@@ -28,26 +28,23 @@
If you chose filename extension matching, this is the extension to be
recognised (the \x0a specials are not allowed). Extension matching is case
sensitive!
- - 'mask' is an (optional, defaults to all 0xff) mask. You can mask out some bits
- from matching by supplying a string like magic and as long as magic. The
- mask is anded with the byte sequence of the file.
+ - 'mask' is an (optional, defaults to all 0xff) mask. You can mask out some
+ bits from matching by supplying a string like magic and as long as magic.
+ The mask is anded with the byte sequence of the file.
- 'interpreter' is the program that should be invoked with the binary as first
argument (specify the full path)
There are some restrictions:
- the whole register string may not exceed 255 characters
- - the magic must resist in the first 128 bytes of the file, i.e. offset+size(magic)
- has to be less than 128
+ - the magic must resist in the first 128 bytes of the file, i.e.
+ offset+size(magic) has to be less than 128
- the interpreter string may not exceed 127 characters
-You may want to add the binary formats in one of your /etc/rc scripts during boot-up.
-Read the manual of your init program to figure out how to do this right.
+You may want to add the binary formats in one of your /etc/rc scripts during
+boot-up. Read the manual of your init program to figure out how to do this
+right.
A few examples (assumed you are in /proc/sys/fs/binfmt_misc):
-- enable Java(TM)-support (like binfmt_java):
- echo ":Java:M::\xca\xfe\xba\xbe::/usr/local/bin/java:" > register
- echo :Applet:M::\<\!--applet::/usr/local/bin/appletviewer: > register
-
- enable support for em86 (like binfmt_em86, for Alpha AXP only):
echo ":i386:M::\x7fELF\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x03:\xff\xff\xff\xff\xff\xfe\xfe\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfb\xff\xff:/bin/em86:" > register
echo ":i486:M::\x7fELF\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x06:\xff\xff\xff\xff\xff\xfe\xfe\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfb\xff\xff:/bin/em86:" > register
@@ -57,8 +54,9 @@
- enable support for DOS/Windows executables (using mzloader and dosemu/wine):
echo ":DOSWin:M::MZ::/usr/sbin/mzloader:" > register
- echo ":DOS:E::com::/usr/sbin/mzloader:" > register
- echo ":DOS2:E::exe::/usr/sbin/mzloader:" > register
+ echo ":DOScom:E::com::/usr/sbin/mzloader:" > register
+ echo ":DOSexe:E::exe::/usr/sbin/mzloader:" > register
+
You can enable/disable binfmt_misc or one binary type by echoing 0 (to disable)
or 1 (to enable) to /proc/sys/fs/binfmt_misc/status or /proc/.../the_name.
@@ -66,6 +64,25 @@
You can remove one entry or all entries by echoing -1 to /proc/.../the_name
or /proc/sys/fs/binfmt_misc/status.
+
+
+Emulating binfmt_java:
+======================
+
+To emulate binfmt_java the following register-strings are necessary
+(the first two for byte-compiled Java binaries, the third for applets
+contained in a html-file). Register exactly in this order!
+ ":Java:M::\xca\xfe\xba\xbe::/usr/local/java/bin/java:"
+ ":JavaC:e::class::/usr/local/java/bin/java:"
+ ":Applet:E::html::/usr/local/java/bin/appletviewer:"
+
+To add a Java-executable to your path you can either make a symbolic
+link to the .class file elsewhere in your path (cut the .class-extension
+in the destination name for convenience) or add the directory of your
+.class files to your PATH environment. In both cases, ensure that the
+.class files are in your CLASSPATH environment!
+
+This is sort of ugly - Javas filename handling is just broken.
HINTS:
diff -u --recursive --new-file pre-linux-2.1.45-6/fs/binfmt_misc.c pre-linux-2.1.45-6x/fs/binfmt_misc.c
--- pre-linux-2.1.45-6/fs/binfmt_misc.c Tue Jul 15 14:29:01 1997
+++ pre-linux-2.1.45-6x/fs/binfmt_misc.c Tue Jul 15 23:00:57 1997
@@ -50,7 +50,7 @@
#define ENTRY_ENABLED 1 /* the old binfmt_entry.enabled */
#define ENTRY_MAGIC 8 /* not filename detection */
-#define ENTRY_STRIP_EXT 32 /* strip of last filename extension */
+#define ENTRY_STRIP_EXT 32 /* strip off last filename extension */
static int load_misc_binary(struct linux_binprm *bprm, struct pt_regs *regs);
static void entry_proc_cleanup(struct binfmt_entry *e);
@@ -162,6 +162,7 @@
char *iname_addr = iname, *p;
int retval, fmt_flags = 0;
+ MOD_INC_USE_COUNT;
if (!enabled) {
retval = -ENOEXEC;
goto _ret;
@@ -208,6 +209,7 @@
if (retval >= 0)
retval = search_binary_handler(bprm, regs);
_ret:
+ MOD_DEC_USE_COUNT;
return retval;
}
@@ -266,13 +268,18 @@
struct binfmt_entry *e;
int memsize, cnt = count - 1, err = 0;
+ MOD_INC_USE_COUNT;
/* some sanity checks */
- if ((count < 11) || (count > 256))
- return -EINVAL;
+ if ((count < 11) || (count > 256)) {
+ err = -EINVAL;
+ goto _err;
+ }
memsize = sizeof(struct binfmt_entry) + count;
- if (!(e = (struct binfmt_entry *) kmalloc(memsize, GFP_USER)))
- return -ENOMEM;
+ if (!(e = (struct binfmt_entry *) kmalloc(memsize, GFP_USER))) {
+ err = -ENOMEM;
+ goto _err;
+ }
sp = buffer + 1;
del = buffer[0];
@@ -309,7 +316,8 @@
!(e->proc_name) || !(e->interpreter) ||
entry_proc_setup(e)) {
kfree(e);
- return -EINVAL;
+ err = -EINVAL;
+ goto _err;
}
write_lock(&entries_lock);
@@ -317,7 +325,10 @@
entries = e;
write_unlock(&entries_lock);
- return count;
+ err = count;
+_err:
+ MOD_DEC_USE_COUNT;
+ return err;
}
/*
@@ -332,6 +343,7 @@
char *dp;
int elen, i;
+ MOD_INC_USE_COUNT;
#ifndef VERBOSE_STATUS
if (data) {
read_lock(&entries_lock);
@@ -391,6 +403,7 @@
*eof = (elen <= count) ? 1 : 0;
*start = page + off;
+ MOD_DEC_USE_COUNT;
return elen;
}
@@ -404,6 +417,7 @@
struct binfmt_entry *e;
int res = count;
+ MOD_INC_USE_COUNT;
if (((buffer[0] == '1') || (buffer[0] == '0')) &&
((count == 1) || ((count == 2) && (buffer[1] == '\n')))) {
if (data) {
@@ -423,6 +437,7 @@
} else {
res = -EINVAL;
}
+ MOD_DEC_USE_COUNT;
return res;
}
diff -u --recursive --new-file pre-linux-2.1.45-6/kernel/ksyms.c pre-linux-2.1.45-6x/kernel/ksyms.c
--- pre-linux-2.1.45-6/kernel/ksyms.c Tue Jul 15 15:47:49 1997
+++ pre-linux-2.1.45-6x/kernel/ksyms.c Tue Jul 15 15:48:04 1997
@@ -178,6 +178,8 @@
EXPORT_SYMBOL(posix_test_lock);
EXPORT_SYMBOL(posix_block_lock);
EXPORT_SYMBOL(posix_unblock_lock);
+EXPORT_SYMBOL(dput);
+EXPORT_SYMBOL(dget);
#if !defined(CONFIG_NFSD) && defined(CONFIG_NFSD_MODULE)
EXPORT_SYMBOL(do_nfsservctl);