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-rw-r--r--vidix/kernelhelper/dhahelper.c361
1 files changed, 361 insertions, 0 deletions
diff --git a/vidix/kernelhelper/dhahelper.c b/vidix/kernelhelper/dhahelper.c
new file mode 100644
index 0000000000..f5b6fe825c
--- /dev/null
+++ b/vidix/kernelhelper/dhahelper.c
@@ -0,0 +1,361 @@
+/*
+ Direct Hardware Access kernel helper
+
+ (C) 2002 Alex Beregszaszi <alex@fsn.hu>
+
+ Accessing hardware from userspace as USER (no root needed!)
+
+ Tested on 2.2.x (2.2.19) and 2.4.x (2.4.3,2.4.17).
+
+ License: GPL
+
+ WARNING! THIS MODULE VIOLATES SEVERAL SECURITY LINES! DON'T USE IT
+ ON PRODUCTION SYSTEMS, ONLY AT HOME, ON A "SINGLE-USER" SYSTEM.
+ NO WARRANTY!
+
+ Tech:
+ Communication between userspace and kernelspace goes over character
+ device using ioctl.
+
+ Usage:
+ mknod -m 666 /dev/dhahelper c 180 0
+
+ Also you can change the major number, setting the "dhahelper_major"
+ module parameter, the default is 180, specified in dhahelper.h.
+
+ Note: do not use other than minor==0, the module forbids it.
+
+ TODO:
+ * do memory mapping without fops:mmap
+ * implement unmap memory
+ * select (request?) a "valid" major number (from Linux project? ;)
+ * make security
+ * is pci handling needed? (libdha does this with lowlevel port funcs)
+ * is mttr handling needed?
+ * test on older kernels (2.0.x (?))
+*/
+
+#ifndef MODULE
+#define MODULE
+#endif
+
+#ifndef __KERNEL__
+#define __KERNEL__
+#endif
+
+#include <linux/config.h>
+
+#ifdef CONFIG_MODVERSION
+#define MODVERSION
+#include <linux/modversions.h>
+#endif
+
+#include <linux/version.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,4,10)
+#include <linux/malloc.h>
+#else
+#include <linux/slab.h>
+#endif
+
+#include <linux/pci.h>
+#include <linux/ioport.h>
+#include <linux/init.h>
+
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <asm/io.h>
+
+#include <linux/mman.h>
+
+#include <linux/fs.h>
+#include <linux/unistd.h>
+
+#include "dhahelper.h"
+
+MODULE_AUTHOR("Alex Beregszaszi <alex@fsn.hu>");
+MODULE_DESCRIPTION("Provides userspace access to hardware (security violation!)");
+#ifdef MODULE_LICENSE
+MODULE_LICENSE("GPL");
+#endif
+
+static int dhahelper_major = DEFAULT_MAJOR;
+MODULE_PARM(dhahelper_major, "i");
+MODULE_PARM_DESC(dhahelper_major, "Major number of dhahelper characterdevice");
+
+/* 0 = silent */
+/* 1 = report errors (default) */
+/* 2 = debug */
+static int dhahelper_verbosity = 1;
+MODULE_PARM(dhahelper_verbosity, "i");
+MODULE_PARM_DESC(dhahelper_verbosity, "Level of verbosity (0 = silent, 1 = only errors, 2 = debug)");
+
+static dhahelper_memory_t last_mem_request;
+
+
+static int dhahelper_open(struct inode *inode, struct file *file)
+{
+ if (dhahelper_verbosity > 1)
+ printk(KERN_DEBUG "dhahelper: device opened\n");
+
+ if (MINOR(inode->i_rdev) != 0)
+ return(-ENXIO);
+
+ MOD_INC_USE_COUNT;
+
+ return(0);
+}
+
+static int dhahelper_release(struct inode *inode, struct file *file)
+{
+ if (dhahelper_verbosity > 1)
+ printk(KERN_DEBUG "dhahelper: device released\n");
+
+ if (MINOR(inode->i_rdev) != 0)
+ return(-ENXIO);
+
+ MOD_DEC_USE_COUNT;
+
+ return(0);
+}
+
+static int dhahelper_ioctl(struct inode *inode, struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+ if (dhahelper_verbosity > 1)
+ printk(KERN_DEBUG "dhahelper: ioctl(cmd=%x, arg=%lx)\n",
+ cmd, arg);
+
+ if (MINOR(inode->i_rdev) != 0)
+ return(-ENXIO);
+
+ switch(cmd)
+ {
+ case DHAHELPER_GET_VERSION:
+ {
+ int version = API_VERSION;
+
+ if (copy_to_user((int *)arg, &version, sizeof(int)))
+ {
+ if (dhahelper_verbosity > 0)
+ printk(KERN_ERR "dhahelper: failed copy to userspace\n");
+ return(-EFAULT);
+ }
+
+ break;
+ }
+ case DHAHELPER_PORT:
+ {
+ dhahelper_port_t port;
+
+ if (copy_from_user(&port, (dhahelper_port_t *)arg, sizeof(dhahelper_port_t)))
+ {
+ if (dhahelper_verbosity > 0)
+ printk(KERN_ERR "dhahelper: failed copy from userspace\n");
+ return(-EFAULT);
+ }
+
+ switch(port.operation)
+ {
+ case PORT_OP_READ:
+ {
+ switch(port.size)
+ {
+ case 1:
+ port.value = inb(port.addr);
+ break;
+ case 2:
+ port.value = inw(port.addr);
+ break;
+ case 4:
+ port.value = inl(port.addr);
+ break;
+ default:
+ if (dhahelper_verbosity > 0)
+ printk(KERN_ERR "dhahelper: invalid port read size (%d)\n",
+ port.size);
+ return(-EINVAL);
+ }
+ break;
+ }
+ case PORT_OP_WRITE:
+ {
+ switch(port.size)
+ {
+ case 1:
+ outb(port.value, port.addr);
+ break;
+ case 2:
+ outw(port.value, port.addr);
+ break;
+ case 4:
+ outl(port.value, port.addr);
+ break;
+ default:
+ if (dhahelper_verbosity > 0)
+ printk(KERN_ERR "dhahelper: invalid port write size (%d)\n",
+ port.size);
+ return(-EINVAL);
+ }
+ break;
+ }
+ default:
+ if (dhahelper_verbosity > 0)
+ printk(KERN_ERR "dhahelper: invalid port operation (%d)\n",
+ port.operation);
+ return(-EINVAL);
+ }
+
+ /* copy back only if read was performed */
+ if (port.operation == PORT_OP_READ)
+ if (copy_to_user((dhahelper_port_t *)arg, &port, sizeof(dhahelper_port_t)))
+ {
+ if (dhahelper_verbosity > 0)
+ printk(KERN_ERR "dhahelper: failed copy to userspace\n");
+ return(-EFAULT);
+ }
+
+ break;
+ }
+ case DHAHELPER_MEMORY:
+ {
+ dhahelper_memory_t mem;
+
+ if (copy_from_user(&mem, (dhahelper_memory_t *)arg, sizeof(dhahelper_memory_t)))
+ {
+ if (dhahelper_verbosity > 0)
+ printk(KERN_ERR "dhahelper: failed copy from userspace\n");
+ return(-EFAULT);
+ }
+
+ switch(mem.operation)
+ {
+ case MEMORY_OP_MAP:
+ {
+#if 1
+ memcpy(&last_mem_request, &mem, sizeof(dhahelper_memory_t));
+#else
+ mem.ret = do_mmap(file, mem.start, mem.size, PROT_READ|PROT_WRITE,
+ MAP_SHARED, mem.offset);
+#endif
+
+ break;
+ }
+ case MEMORY_OP_UNMAP:
+ break;
+ default:
+ if (dhahelper_verbosity > 0)
+ printk(KERN_ERR "dhahelper: invalid memory operation (%d)\n",
+ mem.operation);
+ return(-EINVAL);
+ }
+
+ if (copy_to_user((dhahelper_memory_t *)arg, &mem, sizeof(dhahelper_memory_t)))
+ {
+ if (dhahelper_verbosity > 0)
+ printk(KERN_ERR "dhahelper: failed copy to userspace\n");
+ return(-EFAULT);
+ }
+
+ break;
+ }
+ default:
+ if (dhahelper_verbosity > 0)
+ printk(KERN_ERR "dhahelper: invalid ioctl (%x)\n", cmd);
+ return(-EINVAL);
+ }
+
+ return(0);
+}
+
+static int dhahelper_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ if (last_mem_request.operation != MEMORY_OP_MAP)
+ {
+ if (dhahelper_verbosity > 0)
+ printk(KERN_ERR "dhahelper: mapping not requested before mmap\n");
+ return(-EFAULT);
+ }
+
+ if (dhahelper_verbosity > 1)
+ printk(KERN_INFO "dhahelper: mapping %x (size: %x)\n",
+ last_mem_request.start+last_mem_request.offset, last_mem_request.size);
+
+ if (remap_page_range(0, last_mem_request.start + last_mem_request.offset,
+ last_mem_request.size, vma->vm_page_prot))
+ {
+ if (dhahelper_verbosity > 0)
+ printk(KERN_ERR "dhahelper: error mapping memory\n");
+ return(-EFAULT);
+ }
+
+ return(0);
+}
+
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,4,0)
+static struct file_operations dhahelper_fops =
+{
+ /*llseek*/ NULL,
+ /*read*/ NULL,
+ /*write*/ NULL,
+ /*readdir*/ NULL,
+ /*poll*/ NULL,
+ /*ioctl*/ dhahelper_ioctl,
+ /*mmap*/ dhahelper_mmap,
+ /*open*/ dhahelper_open,
+ /*flush*/ NULL,
+ /*release*/ dhahelper_release,
+ /* zero out the last 5 entries too ? */
+};
+#else
+static struct file_operations dhahelper_fops =
+{
+ owner: THIS_MODULE,
+ ioctl: dhahelper_ioctl,
+ mmap: dhahelper_mmap,
+ open: dhahelper_open,
+ release: dhahelper_release
+};
+#endif
+
+#if KERNEL_VERSION < KERNEL_VERSION(2,4,0)
+int init_module(void)
+#else
+static int __init init_dhahelper(void)
+#endif
+{
+ printk(KERN_INFO "Direct Hardware Access kernel helper (C) Alex Beregszaszi\n");
+
+ if(register_chrdev(dhahelper_major, "dhahelper", &dhahelper_fops))
+ {
+ if (dhahelper_verbosity > 0)
+ printk(KERN_ERR "dhahelper: unable to register character device (major: %d)\n",
+ dhahelper_major);
+ return(-EIO);
+ }
+
+ return(0);
+}
+
+#if KERNEL_VERSION < KERNEL_VERSION(2,4,0)
+void cleanup_module(void)
+#else
+static void __exit exit_dhahelper(void)
+#endif
+{
+ unregister_chrdev(dhahelper_major, "dhahelper");
+}
+
+EXPORT_NO_SYMBOLS;
+
+#if KERNEL_VERSION >= KERNEL_VERSION(2,4,0)
+module_init(init_dhahelper);
+module_exit(exit_dhahelper);
+#endif
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