patch-2.1.75 linux/include/linux/filter.h

• Lines: 108
• Date: Sun Dec 21 17:41:24 1997
• Orig file: v2.1.74/linux/include/linux/filter.h
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.1.74/linux/include/linux/filter.h linux/include/linux/filter.h
@@ -0,0 +1,107 @@
+/*
+ * Linux Socket Filter Data Structures
+ */
+
+#ifndef __LINUX_FILTER_H__
+#define __LINUX_FILTER_H__
+
+/*
+ * Current version of the filter code architecture.
+ */
+#define BPF_MAJOR_VERSION 1
+#define BPF_MINOR_VERSION 1
+
+/*
+ *	Try and keep these values and structures similar to BSD, especially
+ *	the BPF code definitions which need to match so you can share filters
+ */
+ 
+struct sock_filter	/* Filter block */
+{
+        u16	code;   /* Actual filter code */
+        u8	jt;	/* Jump true */
+        u8	jf;	/* Jump false */
+        u32	k;      /* Generic multiuse field */
+};
+
+struct sock_fprog	/* Required for SO_ATTACH_FILTER. */
+{
+        unsigned short         len;	/* Number of filter blocks */
+        struct sock_filter     *filter;
+};
+
+/*
+ * Instruction classes
+ */
+
+#define BPF_CLASS(code) ((code) & 0x07)
+#define         BPF_LD          0x00
+#define         BPF_LDX         0x01
+#define         BPF_ST          0x02
+#define         BPF_STX         0x03
+#define         BPF_ALU         0x04
+#define         BPF_JMP         0x05
+#define         BPF_RET         0x06
+#define         BPF_MISC        0x07
+
+/* ld/ldx fields */
+#define BPF_SIZE(code)  ((code) & 0x18)
+#define         BPF_W           0x00
+#define         BPF_H           0x08
+#define         BPF_B           0x10
+#define BPF_MODE(code)  ((code) & 0xe0)
+#define         BPF_IMM         0x00
+#define         BPF_ABS         0x20
+#define         BPF_IND         0x40
+#define         BPF_MEM         0x60
+#define         BPF_LEN         0x80
+#define         BPF_MSH         0xa0
+
+/* alu/jmp fields */
+#define BPF_OP(code)    ((code) & 0xf0)
+#define         BPF_ADD         0x00
+#define         BPF_SUB         0x10
+#define         BPF_MUL         0x20
+#define         BPF_DIV         0x30
+#define         BPF_OR          0x40
+#define         BPF_AND         0x50
+#define         BPF_LSH         0x60
+#define         BPF_RSH         0x70
+#define         BPF_NEG         0x80
+#define         BPF_JA          0x00
+#define         BPF_JEQ         0x10
+#define         BPF_JGT         0x20
+#define         BPF_JGE         0x30
+#define         BPF_JSET        0x40
+#define BPF_SRC(code)   ((code) & 0x08)
+#define         BPF_K           0x00
+#define         BPF_X           0x08
+
+/* ret - BPF_K and BPF_X also apply */
+#define BPF_RVAL(code)  ((code) & 0x18)
+#define         BPF_A           0x10
+
+/* misc */
+#define BPF_MISCOP(code) ((code) & 0xf8)
+#define         BPF_TAX         0x00
+#define         BPF_TXA         0x80
+
+#define BPF_MAXINSNS 512
+
+/*
+ * Macros for filter block array initializers.
+ */
+#define BPF_STMT(code, k) { (unsigned short)(code), 0, 0, k }
+#define BPF_JUMP(code, k, jt, jf) { (unsigned short)(code), jt, jf, k }
+
+/*
+ * Number of scratch memory words for: BPF_ST and BPF_STX
+ */
+#define BPF_MEMWORDS 16
+
+#ifdef __KERNEL__
+extern int sk_run_filter(unsigned char *data, int len, struct sock_filter *filter, int flen);
+extern int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk);
+#endif /* __KERNEL__ */
+
+#endif /* __LINUX_FILTER_H__ */