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-rw-r--r--wiretap/bpf-engine.c318
1 files changed, 0 insertions, 318 deletions
diff --git a/wiretap/bpf-engine.c b/wiretap/bpf-engine.c
deleted file mode 100644
index d1bff53587..0000000000
--- a/wiretap/bpf-engine.c
+++ /dev/null
@@ -1,318 +0,0 @@
-/* bpf-engine.c
- * ------------
- * The BPF engine used for offline ("display") filters in wiretap.
- * The code is taken from the Linux Socket Filter, and only slightly
- * modified for use in wiretap.
- *
- * Gilbert Ramirez <gram@verdict.uthscsa.edu>
- */
-
-/*
- * Linux Socket Filter - Kernel level socket filtering
- *
- * Author:
- * Jay Schulist <Jay.Schulist@spacs.k12.wi.us>
- *
- * Based on the design of:
- * - The Berkeley Packet Filter
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
- */
-
-#include <glib.h>
-#include "wtap.h"
-#include "bpf-engine.h"
-
-
-/*
- * Decode and apply filter instructions to the skb->data.
- * Return length to keep, 0 for none. skb is the data we are
- * filtering, filter is the array of filter instructions, and
- * len is the number of filter blocks in the array.
- */
-
-int bpf_run_filter(unsigned char *data, int len, struct bpf_instruction *filter, int flen)
-{
- struct bpf_instruction *fentry; /* We walk down these */
- guint32 A = 0; /* Accumulator */
- guint32 X = 0; /* Index Register */
- guint32 mem[BPF_MEMWORDS]; /* Scratch Memory Store */
- int k;
- int pc;
- int *t;
-
- /*
- * Process array of filter instructions.
- */
-
- for(pc = 0; pc < flen; pc++)
- {
- fentry = &filter[pc];
- if(fentry->code & BPF_X)
- t=&X;
- else
- t=&fentry->k;
-
- switch(fentry->code)
- {
- case BPF_ALU|BPF_ADD|BPF_X:
- case BPF_ALU|BPF_ADD|BPF_K:
- A += *t;
- continue;
-
- case BPF_ALU|BPF_SUB|BPF_X:
- case BPF_ALU|BPF_SUB|BPF_K:
- A -= *t;
- continue;
-
- case BPF_ALU|BPF_MUL|BPF_X:
- case BPF_ALU|BPF_MUL|BPF_K:
- A *= *t;
- continue;
-
- case BPF_ALU|BPF_DIV|BPF_X:
- case BPF_ALU|BPF_DIV|BPF_K:
- if(*t == 0)
- return (0);
- A /= *t;
- continue;
-
- case BPF_ALU|BPF_AND|BPF_X:
- case BPF_ALU|BPF_AND|BPF_K:
- A &= *t;
- continue;
-
- case BPF_ALU|BPF_OR|BPF_X:
- case BPF_ALU|BPF_OR|BPF_K:
- A |= *t;
- continue;
-
- case BPF_ALU|BPF_LSH|BPF_X:
- case BPF_ALU|BPF_LSH|BPF_K:
- A <<= *t;
- continue;
-
- case BPF_ALU|BPF_RSH|BPF_X:
- case BPF_ALU|BPF_RSH|BPF_K:
- A >>= *t;
- continue;
-
- case BPF_ALU|BPF_NEG:
- A = -A;
- continue;
-
- case BPF_JMP|BPF_JA:
- pc += fentry->k;
- continue;
-
- case BPF_JMP|BPF_JGT|BPF_K:
- pc += (A > fentry->k) ? fentry->jt : fentry->jf;
- continue;
-
- case BPF_JMP|BPF_JGE|BPF_K:
- pc += (A >= fentry->k) ? fentry->jt : fentry->jf;
- continue;
-
- case BPF_JMP|BPF_JEQ|BPF_K:
- pc += (A == fentry->k) ? fentry->jt : fentry->jf;
- continue;
-
- case BPF_JMP|BPF_JSET|BPF_K:
- pc += (A & fentry->k) ? fentry->jt : fentry->jf;
- continue;
-
- case BPF_JMP|BPF_JGT|BPF_X:
- pc += (A > X) ? fentry->jt : fentry->jf;
- continue;
-
- case BPF_JMP|BPF_JGE|BPF_X:
- pc += (A >= X) ? fentry->jt : fentry->jf;
- continue;
-
- case BPF_JMP|BPF_JEQ|BPF_X:
- pc += (A == X) ? fentry->jt : fentry->jf;
- continue;
-
- case BPF_JMP|BPF_JSET|BPF_X:
- pc += (A & X) ? fentry->jt : fentry->jf;
- continue;
- case BPF_LD|BPF_W|BPF_ABS:
- k = fentry->k;
- if(k + sizeof(long) > len)
- return (0);
- A = pntohl(&data[k]);
- continue;
-
- case BPF_LD|BPF_H|BPF_ABS:
- k = fentry->k;
- if(k + sizeof(short) > len)
- return (0);
- A = pntohs(&data[k]);
- continue;
-
- case BPF_LD|BPF_B|BPF_ABS:
- k = fentry->k;
- if(k >= len)
- return (0);
- A = data[k];
- continue;
-
- case BPF_LD|BPF_W|BPF_LEN:
- A = len;
- continue;
-
- case BPF_LDX|BPF_W|BPF_LEN:
- X = len;
- continue;
-
- case BPF_LD|BPF_W|BPF_IND:
- k = X + fentry->k;
- if(k + sizeof(guint32) > len)
- return (0);
- A = pntohl(&data[k]);
- continue;
-
- case BPF_LD|BPF_H|BPF_IND:
- k = X + fentry->k;
- if(k + sizeof(guint16) > len)
- return (0);
- A = pntohs(&data[k]);
- continue;
-
- case BPF_LD|BPF_B|BPF_IND:
- k = X + fentry->k;
- if(k >= len)
- return (0);
- A = data[k];
- continue;
-
- case BPF_LDX|BPF_B|BPF_MSH:
- /*
- * Hack for BPF to handle TOS etc
- */
- k = fentry->k;
- if(k >= len)
- return (0);
- X = (data[fentry->k] & 0xf) << 2;
- continue;
-
- case BPF_LD|BPF_IMM:
- A = fentry->k;
- continue;
-
- case BPF_LDX|BPF_IMM:
- X = fentry->k;
- continue;
-
- case BPF_LD|BPF_MEM:
- A = mem[fentry->k];
- continue;
-
- case BPF_LDX|BPF_MEM:
- X = mem[fentry->k];
- continue;
-
- case BPF_MISC|BPF_TAX:
- X = A;
- continue;
-
- case BPF_MISC|BPF_TXA:
- A = X;
- continue;
-
- case BPF_RET|BPF_K:
- return ((unsigned int)fentry->k);
-
- case BPF_RET|BPF_A:
- return ((unsigned int)A);
-
- case BPF_ST:
- mem[fentry->k] = A;
- continue;
-
- case BPF_STX:
- mem[fentry->k] = X;
- continue;
-
-
-
- default:
- /* Invalid instruction counts as RET */
- return (0);
- }
- }
-
- g_error("Filter ruleset ran off the end.\n");
- return (0);
-}
-
-/*
- * Check the user's filter code. If we let some ugly
- * filter code slip through kaboom!
- */
-
-int bpf_chk_filter(struct bpf_instruction *filter, int flen)
-{
- struct bpf_instruction *ftest;
- int pc;
-
- /*
- * Check the filter code now.
- */
- for(pc = 0; pc < flen; pc++)
- {
- /*
- * All jumps are forward as they are not signed
- */
-
- ftest = &filter[pc];
- if(BPF_CLASS(ftest->code) == BPF_JMP)
- {
- /*
- * But they mustn't jump off the end.
- */
- if(BPF_OP(ftest->code) == BPF_JA)
- {
- if(pc + ftest->k + 1>= (unsigned)flen)
- return (-1);
- }
- else
- {
- /*
- * For conditionals both must be safe
- */
- if(pc + ftest->jt +1 >= flen || pc + ftest->jf +1 >= flen)
- return (-1);
- }
- }
-
- /*
- * Check that memory operations use valid addresses.
- */
-
- if(ftest->k <0 || ftest->k >= BPF_MEMWORDS)
- {
- /*
- * But it might not be a memory operation...
- */
-
- if (BPF_CLASS(ftest->code) == BPF_ST)
- return -1;
- if((BPF_CLASS(ftest->code) == BPF_LD) &&
- (BPF_MODE(ftest->code) == BPF_MEM))
- return (-1);
- }
- }
-
- /*
- * The program must end with a return. We don't care where they
- * jumped within the script (its always forwards) but in the
- * end they _will_ hit this.
- */
-
- return (BPF_CLASS(filter[flen - 1].code) == BPF_RET)?0:-1;
-}
-
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-27 02:20:58 +0000