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authorJakub Kicinski <jakub.kicinski@netronome.com>2017-10-04 20:10:03 -0700
committerDavid S. Miller <davem@davemloft.net>2017-10-04 21:45:05 -0700
commita92bb546cff0b31d96d5919ebfeda9c678756b42 (patch)
tree74bfc93750a0fe9fce2601edec22f02baa46b562 /tools/net/bpf_dbg.c
parentMerge branch 'enslavement-extack' (diff)
downloadlinux-dev-a92bb546cff0b31d96d5919ebfeda9c678756b42.tar.xz
linux-dev-a92bb546cff0b31d96d5919ebfeda9c678756b42.zip
tools: rename tools/net directory to tools/bpf
We currently only have BPF tools in the tools/net directory. We are about to add more BPF tools there, not necessarily networking related, rename the directory and related Makefile targets to bpf. Suggested-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Simon Horman <simon.horman@netronome.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'tools/net/bpf_dbg.c')
-rw-r--r--tools/net/bpf_dbg.c1395
1 files changed, 0 insertions, 1395 deletions
diff --git a/tools/net/bpf_dbg.c b/tools/net/bpf_dbg.c
deleted file mode 100644
index 4f254bcc4423..000000000000
--- a/tools/net/bpf_dbg.c
+++ /dev/null
@@ -1,1395 +0,0 @@
-/*
- * Minimal BPF debugger
- *
- * Minimal BPF debugger that mimics the kernel's engine (w/o extensions)
- * and allows for single stepping through selected packets from a pcap
- * with a provided user filter in order to facilitate verification of a
- * BPF program. Besides others, this is useful to verify BPF programs
- * before attaching to a live system, and can be used in socket filters,
- * cls_bpf, xt_bpf, team driver and e.g. PTP code; in particular when a
- * single more complex BPF program is being used. Reasons for a more
- * complex BPF program are likely primarily to optimize execution time
- * for making a verdict when multiple simple BPF programs are combined
- * into one in order to prevent parsing same headers multiple times.
- *
- * More on how to debug BPF opcodes see Documentation/networking/filter.txt
- * which is the main document on BPF. Mini howto for getting started:
- *
- * 1) `./bpf_dbg` to enter the shell (shell cmds denoted with '>'):
- * 2) > load bpf 6,40 0 0 12,21 0 3 20... (output from `bpf_asm` or
- * `tcpdump -iem1 -ddd port 22 | tr '\n' ','` to load as filter)
- * 3) > load pcap foo.pcap
- * 4) > run <n>/disassemble/dump/quit (self-explanatory)
- * 5) > breakpoint 2 (sets bp at loaded BPF insns 2, do `run` then;
- * multiple bps can be set, of course, a call to `breakpoint`
- * w/o args shows currently loaded bps, `breakpoint reset` for
- * resetting all breakpoints)
- * 6) > select 3 (`run` etc will start from the 3rd packet in the pcap)
- * 7) > step [-<n>, +<n>] (performs single stepping through the BPF)
- *
- * Copyright 2013 Daniel Borkmann <borkmann@redhat.com>
- * Licensed under the GNU General Public License, version 2.0 (GPLv2)
- */
-
-#include <stdio.h>
-#include <unistd.h>
-#include <stdlib.h>
-#include <ctype.h>
-#include <stdbool.h>
-#include <stdarg.h>
-#include <setjmp.h>
-#include <linux/filter.h>
-#include <linux/if_packet.h>
-#include <readline/readline.h>
-#include <readline/history.h>
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <sys/stat.h>
-#include <sys/mman.h>
-#include <fcntl.h>
-#include <errno.h>
-#include <signal.h>
-#include <arpa/inet.h>
-#include <net/ethernet.h>
-
-#define TCPDUMP_MAGIC 0xa1b2c3d4
-
-#define BPF_LDX_B (BPF_LDX | BPF_B)
-#define BPF_LDX_W (BPF_LDX | BPF_W)
-#define BPF_JMP_JA (BPF_JMP | BPF_JA)
-#define BPF_JMP_JEQ (BPF_JMP | BPF_JEQ)
-#define BPF_JMP_JGT (BPF_JMP | BPF_JGT)
-#define BPF_JMP_JGE (BPF_JMP | BPF_JGE)
-#define BPF_JMP_JSET (BPF_JMP | BPF_JSET)
-#define BPF_ALU_ADD (BPF_ALU | BPF_ADD)
-#define BPF_ALU_SUB (BPF_ALU | BPF_SUB)
-#define BPF_ALU_MUL (BPF_ALU | BPF_MUL)
-#define BPF_ALU_DIV (BPF_ALU | BPF_DIV)
-#define BPF_ALU_MOD (BPF_ALU | BPF_MOD)
-#define BPF_ALU_NEG (BPF_ALU | BPF_NEG)
-#define BPF_ALU_AND (BPF_ALU | BPF_AND)
-#define BPF_ALU_OR (BPF_ALU | BPF_OR)
-#define BPF_ALU_XOR (BPF_ALU | BPF_XOR)
-#define BPF_ALU_LSH (BPF_ALU | BPF_LSH)
-#define BPF_ALU_RSH (BPF_ALU | BPF_RSH)
-#define BPF_MISC_TAX (BPF_MISC | BPF_TAX)
-#define BPF_MISC_TXA (BPF_MISC | BPF_TXA)
-#define BPF_LD_B (BPF_LD | BPF_B)
-#define BPF_LD_H (BPF_LD | BPF_H)
-#define BPF_LD_W (BPF_LD | BPF_W)
-
-#ifndef array_size
-# define array_size(x) (sizeof(x) / sizeof((x)[0]))
-#endif
-
-#ifndef __check_format_printf
-# define __check_format_printf(pos_fmtstr, pos_fmtargs) \
- __attribute__ ((format (printf, (pos_fmtstr), (pos_fmtargs))))
-#endif
-
-enum {
- CMD_OK,
- CMD_ERR,
- CMD_EX,
-};
-
-struct shell_cmd {
- const char *name;
- int (*func)(char *args);
-};
-
-struct pcap_filehdr {
- uint32_t magic;
- uint16_t version_major;
- uint16_t version_minor;
- int32_t thiszone;
- uint32_t sigfigs;
- uint32_t snaplen;
- uint32_t linktype;
-};
-
-struct pcap_timeval {
- int32_t tv_sec;
- int32_t tv_usec;
-};
-
-struct pcap_pkthdr {
- struct pcap_timeval ts;
- uint32_t caplen;
- uint32_t len;
-};
-
-struct bpf_regs {
- uint32_t A;
- uint32_t X;
- uint32_t M[BPF_MEMWORDS];
- uint32_t R;
- bool Rs;
- uint16_t Pc;
-};
-
-static struct sock_filter bpf_image[BPF_MAXINSNS + 1];
-static unsigned int bpf_prog_len;
-
-static int bpf_breakpoints[64];
-static struct bpf_regs bpf_regs[BPF_MAXINSNS + 1];
-static struct bpf_regs bpf_curr;
-static unsigned int bpf_regs_len;
-
-static int pcap_fd = -1;
-static unsigned int pcap_packet;
-static size_t pcap_map_size;
-static char *pcap_ptr_va_start, *pcap_ptr_va_curr;
-
-static const char * const op_table[] = {
- [BPF_ST] = "st",
- [BPF_STX] = "stx",
- [BPF_LD_B] = "ldb",
- [BPF_LD_H] = "ldh",
- [BPF_LD_W] = "ld",
- [BPF_LDX] = "ldx",
- [BPF_LDX_B] = "ldxb",
- [BPF_JMP_JA] = "ja",
- [BPF_JMP_JEQ] = "jeq",
- [BPF_JMP_JGT] = "jgt",
- [BPF_JMP_JGE] = "jge",
- [BPF_JMP_JSET] = "jset",
- [BPF_ALU_ADD] = "add",
- [BPF_ALU_SUB] = "sub",
- [BPF_ALU_MUL] = "mul",
- [BPF_ALU_DIV] = "div",
- [BPF_ALU_MOD] = "mod",
- [BPF_ALU_NEG] = "neg",
- [BPF_ALU_AND] = "and",
- [BPF_ALU_OR] = "or",
- [BPF_ALU_XOR] = "xor",
- [BPF_ALU_LSH] = "lsh",
- [BPF_ALU_RSH] = "rsh",
- [BPF_MISC_TAX] = "tax",
- [BPF_MISC_TXA] = "txa",
- [BPF_RET] = "ret",
-};
-
-static __check_format_printf(1, 2) int rl_printf(const char *fmt, ...)
-{
- int ret;
- va_list vl;
-
- va_start(vl, fmt);
- ret = vfprintf(rl_outstream, fmt, vl);
- va_end(vl);
-
- return ret;
-}
-
-static int matches(const char *cmd, const char *pattern)
-{
- int len = strlen(cmd);
-
- if (len > strlen(pattern))
- return -1;
-
- return memcmp(pattern, cmd, len);
-}
-
-static void hex_dump(const uint8_t *buf, size_t len)
-{
- int i;
-
- rl_printf("%3u: ", 0);
- for (i = 0; i < len; i++) {
- if (i && !(i % 16))
- rl_printf("\n%3u: ", i);
- rl_printf("%02x ", buf[i]);
- }
- rl_printf("\n");
-}
-
-static bool bpf_prog_loaded(void)
-{
- if (bpf_prog_len == 0)
- rl_printf("no bpf program loaded!\n");
-
- return bpf_prog_len > 0;
-}
-
-static void bpf_disasm(const struct sock_filter f, unsigned int i)
-{
- const char *op, *fmt;
- int val = f.k;
- char buf[256];
-
- switch (f.code) {
- case BPF_RET | BPF_K:
- op = op_table[BPF_RET];
- fmt = "#%#x";
- break;
- case BPF_RET | BPF_A:
- op = op_table[BPF_RET];
- fmt = "a";
- break;
- case BPF_RET | BPF_X:
- op = op_table[BPF_RET];
- fmt = "x";
- break;
- case BPF_MISC_TAX:
- op = op_table[BPF_MISC_TAX];
- fmt = "";
- break;
- case BPF_MISC_TXA:
- op = op_table[BPF_MISC_TXA];
- fmt = "";
- break;
- case BPF_ST:
- op = op_table[BPF_ST];
- fmt = "M[%d]";
- break;
- case BPF_STX:
- op = op_table[BPF_STX];
- fmt = "M[%d]";
- break;
- case BPF_LD_W | BPF_ABS:
- op = op_table[BPF_LD_W];
- fmt = "[%d]";
- break;
- case BPF_LD_H | BPF_ABS:
- op = op_table[BPF_LD_H];
- fmt = "[%d]";
- break;
- case BPF_LD_B | BPF_ABS:
- op = op_table[BPF_LD_B];
- fmt = "[%d]";
- break;
- case BPF_LD_W | BPF_LEN:
- op = op_table[BPF_LD_W];
- fmt = "#len";
- break;
- case BPF_LD_W | BPF_IND:
- op = op_table[BPF_LD_W];
- fmt = "[x+%d]";
- break;
- case BPF_LD_H | BPF_IND:
- op = op_table[BPF_LD_H];
- fmt = "[x+%d]";
- break;
- case BPF_LD_B | BPF_IND:
- op = op_table[BPF_LD_B];
- fmt = "[x+%d]";
- break;
- case BPF_LD | BPF_IMM:
- op = op_table[BPF_LD_W];
- fmt = "#%#x";
- break;
- case BPF_LDX | BPF_IMM:
- op = op_table[BPF_LDX];
- fmt = "#%#x";
- break;
- case BPF_LDX_B | BPF_MSH:
- op = op_table[BPF_LDX_B];
- fmt = "4*([%d]&0xf)";
- break;
- case BPF_LD | BPF_MEM:
- op = op_table[BPF_LD_W];
- fmt = "M[%d]";
- break;
- case BPF_LDX | BPF_MEM:
- op = op_table[BPF_LDX];
- fmt = "M[%d]";
- break;
- case BPF_JMP_JA:
- op = op_table[BPF_JMP_JA];
- fmt = "%d";
- val = i + 1 + f.k;
- break;
- case BPF_JMP_JGT | BPF_X:
- op = op_table[BPF_JMP_JGT];
- fmt = "x";
- break;
- case BPF_JMP_JGT | BPF_K:
- op = op_table[BPF_JMP_JGT];
- fmt = "#%#x";
- break;
- case BPF_JMP_JGE | BPF_X:
- op = op_table[BPF_JMP_JGE];
- fmt = "x";
- break;
- case BPF_JMP_JGE | BPF_K:
- op = op_table[BPF_JMP_JGE];
- fmt = "#%#x";
- break;
- case BPF_JMP_JEQ | BPF_X:
- op = op_table[BPF_JMP_JEQ];
- fmt = "x";
- break;
- case BPF_JMP_JEQ | BPF_K:
- op = op_table[BPF_JMP_JEQ];
- fmt = "#%#x";
- break;
- case BPF_JMP_JSET | BPF_X:
- op = op_table[BPF_JMP_JSET];
- fmt = "x";
- break;
- case BPF_JMP_JSET | BPF_K:
- op = op_table[BPF_JMP_JSET];
- fmt = "#%#x";
- break;
- case BPF_ALU_NEG:
- op = op_table[BPF_ALU_NEG];
- fmt = "";
- break;
- case BPF_ALU_LSH | BPF_X:
- op = op_table[BPF_ALU_LSH];
- fmt = "x";
- break;
- case BPF_ALU_LSH | BPF_K:
- op = op_table[BPF_ALU_LSH];
- fmt = "#%d";
- break;
- case BPF_ALU_RSH | BPF_X:
- op = op_table[BPF_ALU_RSH];
- fmt = "x";
- break;
- case BPF_ALU_RSH | BPF_K:
- op = op_table[BPF_ALU_RSH];
- fmt = "#%d";
- break;
- case BPF_ALU_ADD | BPF_X:
- op = op_table[BPF_ALU_ADD];
- fmt = "x";
- break;
- case BPF_ALU_ADD | BPF_K:
- op = op_table[BPF_ALU_ADD];
- fmt = "#%d";
- break;
- case BPF_ALU_SUB | BPF_X:
- op = op_table[BPF_ALU_SUB];
- fmt = "x";
- break;
- case BPF_ALU_SUB | BPF_K:
- op = op_table[BPF_ALU_SUB];
- fmt = "#%d";
- break;
- case BPF_ALU_MUL | BPF_X:
- op = op_table[BPF_ALU_MUL];
- fmt = "x";
- break;
- case BPF_ALU_MUL | BPF_K:
- op = op_table[BPF_ALU_MUL];
- fmt = "#%d";
- break;
- case BPF_ALU_DIV | BPF_X:
- op = op_table[BPF_ALU_DIV];
- fmt = "x";
- break;
- case BPF_ALU_DIV | BPF_K:
- op = op_table[BPF_ALU_DIV];
- fmt = "#%d";
- break;
- case BPF_ALU_MOD | BPF_X:
- op = op_table[BPF_ALU_MOD];
- fmt = "x";
- break;
- case BPF_ALU_MOD | BPF_K:
- op = op_table[BPF_ALU_MOD];
- fmt = "#%d";
- break;
- case BPF_ALU_AND | BPF_X:
- op = op_table[BPF_ALU_AND];
- fmt = "x";
- break;
- case BPF_ALU_AND | BPF_K:
- op = op_table[BPF_ALU_AND];
- fmt = "#%#x";
- break;
- case BPF_ALU_OR | BPF_X:
- op = op_table[BPF_ALU_OR];
- fmt = "x";
- break;
- case BPF_ALU_OR | BPF_K:
- op = op_table[BPF_ALU_OR];
- fmt = "#%#x";
- break;
- case BPF_ALU_XOR | BPF_X:
- op = op_table[BPF_ALU_XOR];
- fmt = "x";
- break;
- case BPF_ALU_XOR | BPF_K:
- op = op_table[BPF_ALU_XOR];
- fmt = "#%#x";
- break;
- default:
- op = "nosup";
- fmt = "%#x";
- val = f.code;
- break;
- }
-
- memset(buf, 0, sizeof(buf));
- snprintf(buf, sizeof(buf), fmt, val);
- buf[sizeof(buf) - 1] = 0;
-
- if ((BPF_CLASS(f.code) == BPF_JMP && BPF_OP(f.code) != BPF_JA))
- rl_printf("l%d:\t%s %s, l%d, l%d\n", i, op, buf,
- i + 1 + f.jt, i + 1 + f.jf);
- else
- rl_printf("l%d:\t%s %s\n", i, op, buf);
-}
-
-static void bpf_dump_curr(struct bpf_regs *r, struct sock_filter *f)
-{
- int i, m = 0;
-
- rl_printf("pc: [%u]\n", r->Pc);
- rl_printf("code: [%u] jt[%u] jf[%u] k[%u]\n",
- f->code, f->jt, f->jf, f->k);
- rl_printf("curr: ");
- bpf_disasm(*f, r->Pc);
-
- if (f->jt || f->jf) {
- rl_printf("jt: ");
- bpf_disasm(*(f + f->jt + 1), r->Pc + f->jt + 1);
- rl_printf("jf: ");
- bpf_disasm(*(f + f->jf + 1), r->Pc + f->jf + 1);
- }
-
- rl_printf("A: [%#08x][%u]\n", r->A, r->A);
- rl_printf("X: [%#08x][%u]\n", r->X, r->X);
- if (r->Rs)
- rl_printf("ret: [%#08x][%u]!\n", r->R, r->R);
-
- for (i = 0; i < BPF_MEMWORDS; i++) {
- if (r->M[i]) {
- m++;
- rl_printf("M[%d]: [%#08x][%u]\n", i, r->M[i], r->M[i]);
- }
- }
- if (m == 0)
- rl_printf("M[0,%d]: [%#08x][%u]\n", BPF_MEMWORDS - 1, 0, 0);
-}
-
-static void bpf_dump_pkt(uint8_t *pkt, uint32_t pkt_caplen, uint32_t pkt_len)
-{
- if (pkt_caplen != pkt_len)
- rl_printf("cap: %u, len: %u\n", pkt_caplen, pkt_len);
- else
- rl_printf("len: %u\n", pkt_len);
-
- hex_dump(pkt, pkt_caplen);
-}
-
-static void bpf_disasm_all(const struct sock_filter *f, unsigned int len)
-{
- unsigned int i;
-
- for (i = 0; i < len; i++)
- bpf_disasm(f[i], i);
-}
-
-static void bpf_dump_all(const struct sock_filter *f, unsigned int len)
-{
- unsigned int i;
-
- rl_printf("/* { op, jt, jf, k }, */\n");
- for (i = 0; i < len; i++)
- rl_printf("{ %#04x, %2u, %2u, %#010x },\n",
- f[i].code, f[i].jt, f[i].jf, f[i].k);
-}
-
-static bool bpf_runnable(struct sock_filter *f, unsigned int len)
-{
- int sock, ret, i;
- struct sock_fprog bpf = {
- .filter = f,
- .len = len,
- };
-
- sock = socket(AF_INET, SOCK_DGRAM, 0);
- if (sock < 0) {
- rl_printf("cannot open socket!\n");
- return false;
- }
- ret = setsockopt(sock, SOL_SOCKET, SO_ATTACH_FILTER, &bpf, sizeof(bpf));
- close(sock);
- if (ret < 0) {
- rl_printf("program not allowed to run by kernel!\n");
- return false;
- }
- for (i = 0; i < len; i++) {
- if (BPF_CLASS(f[i].code) == BPF_LD &&
- f[i].k > SKF_AD_OFF) {
- rl_printf("extensions currently not supported!\n");
- return false;
- }
- }
-
- return true;
-}
-
-static void bpf_reset_breakpoints(void)
-{
- int i;
-
- for (i = 0; i < array_size(bpf_breakpoints); i++)
- bpf_breakpoints[i] = -1;
-}
-
-static void bpf_set_breakpoints(unsigned int where)
-{
- int i;
- bool set = false;
-
- for (i = 0; i < array_size(bpf_breakpoints); i++) {
- if (bpf_breakpoints[i] == (int) where) {
- rl_printf("breakpoint already set!\n");
- set = true;
- break;
- }
-
- if (bpf_breakpoints[i] == -1 && set == false) {
- bpf_breakpoints[i] = where;
- set = true;
- }
- }
-
- if (!set)
- rl_printf("too many breakpoints set, reset first!\n");
-}
-
-static void bpf_dump_breakpoints(void)
-{
- int i;
-
- rl_printf("breakpoints: ");
-
- for (i = 0; i < array_size(bpf_breakpoints); i++) {
- if (bpf_breakpoints[i] < 0)
- continue;
- rl_printf("%d ", bpf_breakpoints[i]);
- }
-
- rl_printf("\n");
-}
-
-static void bpf_reset(void)
-{
- bpf_regs_len = 0;
-
- memset(bpf_regs, 0, sizeof(bpf_regs));
- memset(&bpf_curr, 0, sizeof(bpf_curr));
-}
-
-static void bpf_safe_regs(void)
-{
- memcpy(&bpf_regs[bpf_regs_len++], &bpf_curr, sizeof(bpf_curr));
-}
-
-static bool bpf_restore_regs(int off)
-{
- unsigned int index = bpf_regs_len - 1 + off;
-
- if (index == 0) {
- bpf_reset();
- return true;
- } else if (index < bpf_regs_len) {
- memcpy(&bpf_curr, &bpf_regs[index], sizeof(bpf_curr));
- bpf_regs_len = index;
- return true;
- } else {
- rl_printf("reached bottom of register history stack!\n");
- return false;
- }
-}
-
-static uint32_t extract_u32(uint8_t *pkt, uint32_t off)
-{
- uint32_t r;
-
- memcpy(&r, &pkt[off], sizeof(r));
-
- return ntohl(r);
-}
-
-static uint16_t extract_u16(uint8_t *pkt, uint32_t off)
-{
- uint16_t r;
-
- memcpy(&r, &pkt[off], sizeof(r));
-
- return ntohs(r);
-}
-
-static uint8_t extract_u8(uint8_t *pkt, uint32_t off)
-{
- return pkt[off];
-}
-
-static void set_return(struct bpf_regs *r)
-{
- r->R = 0;
- r->Rs = true;
-}
-
-static void bpf_single_step(struct bpf_regs *r, struct sock_filter *f,
- uint8_t *pkt, uint32_t pkt_caplen,
- uint32_t pkt_len)
-{
- uint32_t K = f->k;
- int d;
-
- switch (f->code) {
- case BPF_RET | BPF_K:
- r->R = K;
- r->Rs = true;
- break;
- case BPF_RET | BPF_A:
- r->R = r->A;
- r->Rs = true;
- break;
- case BPF_RET | BPF_X:
- r->R = r->X;
- r->Rs = true;
- break;
- case BPF_MISC_TAX:
- r->X = r->A;
- break;
- case BPF_MISC_TXA:
- r->A = r->X;
- break;
- case BPF_ST:
- r->M[K] = r->A;
- break;
- case BPF_STX:
- r->M[K] = r->X;
- break;
- case BPF_LD_W | BPF_ABS:
- d = pkt_caplen - K;
- if (d >= sizeof(uint32_t))
- r->A = extract_u32(pkt, K);
- else
- set_return(r);
- break;
- case BPF_LD_H | BPF_ABS:
- d = pkt_caplen - K;
- if (d >= sizeof(uint16_t))
- r->A = extract_u16(pkt, K);
- else
- set_return(r);
- break;
- case BPF_LD_B | BPF_ABS:
- d = pkt_caplen - K;
- if (d >= sizeof(uint8_t))
- r->A = extract_u8(pkt, K);
- else
- set_return(r);
- break;
- case BPF_LD_W | BPF_IND:
- d = pkt_caplen - (r->X + K);
- if (d >= sizeof(uint32_t))
- r->A = extract_u32(pkt, r->X + K);
- break;
- case BPF_LD_H | BPF_IND:
- d = pkt_caplen - (r->X + K);
- if (d >= sizeof(uint16_t))
- r->A = extract_u16(pkt, r->X + K);
- else
- set_return(r);
- break;
- case BPF_LD_B | BPF_IND:
- d = pkt_caplen - (r->X + K);
- if (d >= sizeof(uint8_t))
- r->A = extract_u8(pkt, r->X + K);
- else
- set_return(r);
- break;
- case BPF_LDX_B | BPF_MSH:
- d = pkt_caplen - K;
- if (d >= sizeof(uint8_t)) {
- r->X = extract_u8(pkt, K);
- r->X = (r->X & 0xf) << 2;
- } else
- set_return(r);
- break;
- case BPF_LD_W | BPF_LEN:
- r->A = pkt_len;
- break;
- case BPF_LDX_W | BPF_LEN:
- r->A = pkt_len;
- break;
- case BPF_LD | BPF_IMM:
- r->A = K;
- break;
- case BPF_LDX | BPF_IMM:
- r->X = K;
- break;
- case BPF_LD | BPF_MEM:
- r->A = r->M[K];
- break;
- case BPF_LDX | BPF_MEM:
- r->X = r->M[K];
- break;
- case BPF_JMP_JA:
- r->Pc += K;
- break;
- case BPF_JMP_JGT | BPF_X:
- r->Pc += r->A > r->X ? f->jt : f->jf;
- break;
- case BPF_JMP_JGT | BPF_K:
- r->Pc += r->A > K ? f->jt : f->jf;
- break;
- case BPF_JMP_JGE | BPF_X:
- r->Pc += r->A >= r->X ? f->jt : f->jf;
- break;
- case BPF_JMP_JGE | BPF_K:
- r->Pc += r->A >= K ? f->jt : f->jf;
- break;
- case BPF_JMP_JEQ | BPF_X:
- r->Pc += r->A == r->X ? f->jt : f->jf;
- break;
- case BPF_JMP_JEQ | BPF_K:
- r->Pc += r->A == K ? f->jt : f->jf;
- break;
- case BPF_JMP_JSET | BPF_X:
- r->Pc += r->A & r->X ? f->jt : f->jf;
- break;
- case BPF_JMP_JSET | BPF_K:
- r->Pc += r->A & K ? f->jt : f->jf;
- break;
- case BPF_ALU_NEG:
- r->A = -r->A;
- break;
- case BPF_ALU_LSH | BPF_X:
- r->A <<= r->X;
- break;
- case BPF_ALU_LSH | BPF_K:
- r->A <<= K;
- break;
- case BPF_ALU_RSH | BPF_X:
- r->A >>= r->X;
- break;
- case BPF_ALU_RSH | BPF_K:
- r->A >>= K;
- break;
- case BPF_ALU_ADD | BPF_X:
- r->A += r->X;
- break;
- case BPF_ALU_ADD | BPF_K:
- r->A += K;
- break;
- case BPF_ALU_SUB | BPF_X:
- r->A -= r->X;
- break;
- case BPF_ALU_SUB | BPF_K:
- r->A -= K;
- break;
- case BPF_ALU_MUL | BPF_X:
- r->A *= r->X;
- break;
- case BPF_ALU_MUL | BPF_K:
- r->A *= K;
- break;
- case BPF_ALU_DIV | BPF_X:
- case BPF_ALU_MOD | BPF_X:
- if (r->X == 0) {
- set_return(r);
- break;
- }
- goto do_div;
- case BPF_ALU_DIV | BPF_K:
- case BPF_ALU_MOD | BPF_K:
- if (K == 0) {
- set_return(r);
- break;
- }
-do_div:
- switch (f->code) {
- case BPF_ALU_DIV | BPF_X:
- r->A /= r->X;
- break;
- case BPF_ALU_DIV | BPF_K:
- r->A /= K;
- break;
- case BPF_ALU_MOD | BPF_X:
- r->A %= r->X;
- break;
- case BPF_ALU_MOD | BPF_K:
- r->A %= K;
- break;
- }
- break;
- case BPF_ALU_AND | BPF_X:
- r->A &= r->X;
- break;
- case BPF_ALU_AND | BPF_K:
- r->A &= K;
- break;
- case BPF_ALU_OR | BPF_X:
- r->A |= r->X;
- break;
- case BPF_ALU_OR | BPF_K:
- r->A |= K;
- break;
- case BPF_ALU_XOR | BPF_X:
- r->A ^= r->X;
- break;
- case BPF_ALU_XOR | BPF_K:
- r->A ^= K;
- break;
- }
-}
-
-static bool bpf_pc_has_breakpoint(uint16_t pc)
-{
- int i;
-
- for (i = 0; i < array_size(bpf_breakpoints); i++) {
- if (bpf_breakpoints[i] < 0)
- continue;
- if (bpf_breakpoints[i] == pc)
- return true;
- }
-
- return false;
-}
-
-static bool bpf_handle_breakpoint(struct bpf_regs *r, struct sock_filter *f,
- uint8_t *pkt, uint32_t pkt_caplen,
- uint32_t pkt_len)
-{
- rl_printf("-- register dump --\n");
- bpf_dump_curr(r, &f[r->Pc]);
- rl_printf("-- packet dump --\n");
- bpf_dump_pkt(pkt, pkt_caplen, pkt_len);
- rl_printf("(breakpoint)\n");
- return true;
-}
-
-static int bpf_run_all(struct sock_filter *f, uint16_t bpf_len, uint8_t *pkt,
- uint32_t pkt_caplen, uint32_t pkt_len)
-{
- bool stop = false;
-
- while (bpf_curr.Rs == false && stop == false) {
- bpf_safe_regs();
-
- if (bpf_pc_has_breakpoint(bpf_curr.Pc))
- stop = bpf_handle_breakpoint(&bpf_curr, f, pkt,
- pkt_caplen, pkt_len);
-
- bpf_single_step(&bpf_curr, &f[bpf_curr.Pc], pkt, pkt_caplen,
- pkt_len);
- bpf_curr.Pc++;
- }
-
- return stop ? -1 : bpf_curr.R;
-}
-
-static int bpf_run_stepping(struct sock_filter *f, uint16_t bpf_len,
- uint8_t *pkt, uint32_t pkt_caplen,
- uint32_t pkt_len, int next)
-{
- bool stop = false;
- int i = 1;
-
- while (bpf_curr.Rs == false && stop == false) {
- bpf_safe_regs();
-
- if (i++ == next)
- stop = bpf_handle_breakpoint(&bpf_curr, f, pkt,
- pkt_caplen, pkt_len);
-
- bpf_single_step(&bpf_curr, &f[bpf_curr.Pc], pkt, pkt_caplen,
- pkt_len);
- bpf_curr.Pc++;
- }
-
- return stop ? -1 : bpf_curr.R;
-}
-
-static bool pcap_loaded(void)
-{
- if (pcap_fd < 0)
- rl_printf("no pcap file loaded!\n");
-
- return pcap_fd >= 0;
-}
-
-static struct pcap_pkthdr *pcap_curr_pkt(void)
-{
- return (void *) pcap_ptr_va_curr;
-}
-
-static bool pcap_next_pkt(void)
-{
- struct pcap_pkthdr *hdr = pcap_curr_pkt();
-
- if (pcap_ptr_va_curr + sizeof(*hdr) -
- pcap_ptr_va_start >= pcap_map_size)
- return false;
- if (hdr->caplen == 0 || hdr->len == 0 || hdr->caplen > hdr->len)
- return false;
- if (pcap_ptr_va_curr + sizeof(*hdr) + hdr->caplen -
- pcap_ptr_va_start >= pcap_map_size)
- return false;
-
- pcap_ptr_va_curr += (sizeof(*hdr) + hdr->caplen);
- return true;
-}
-
-static void pcap_reset_pkt(void)
-{
- pcap_ptr_va_curr = pcap_ptr_va_start + sizeof(struct pcap_filehdr);
-}
-
-static int try_load_pcap(const char *file)
-{
- struct pcap_filehdr *hdr;
- struct stat sb;
- int ret;
-
- pcap_fd = open(file, O_RDONLY);
- if (pcap_fd < 0) {
- rl_printf("cannot open pcap [%s]!\n", strerror(errno));
- return CMD_ERR;
- }
-
- ret = fstat(pcap_fd, &sb);
- if (ret < 0) {
- rl_printf("cannot fstat pcap file!\n");
- return CMD_ERR;
- }
-
- if (!S_ISREG(sb.st_mode)) {
- rl_printf("not a regular pcap file, duh!\n");
- return CMD_ERR;
- }
-
- pcap_map_size = sb.st_size;
- if (pcap_map_size <= sizeof(struct pcap_filehdr)) {
- rl_printf("pcap file too small!\n");
- return CMD_ERR;
- }
-
- pcap_ptr_va_start = mmap(NULL, pcap_map_size, PROT_READ,
- MAP_SHARED | MAP_LOCKED, pcap_fd, 0);
- if (pcap_ptr_va_start == MAP_FAILED) {
- rl_printf("mmap of file failed!");
- return CMD_ERR;
- }
-
- hdr = (void *) pcap_ptr_va_start;
- if (hdr->magic != TCPDUMP_MAGIC) {
- rl_printf("wrong pcap magic!\n");
- return CMD_ERR;
- }
-
- pcap_reset_pkt();
-
- return CMD_OK;
-
-}
-
-static void try_close_pcap(void)
-{
- if (pcap_fd >= 0) {
- munmap(pcap_ptr_va_start, pcap_map_size);
- close(pcap_fd);
-
- pcap_ptr_va_start = pcap_ptr_va_curr = NULL;
- pcap_map_size = 0;
- pcap_packet = 0;
- pcap_fd = -1;
- }
-}
-
-static int cmd_load_bpf(char *bpf_string)
-{
- char sp, *token, separator = ',';
- unsigned short bpf_len, i = 0;
- struct sock_filter tmp;
-
- bpf_prog_len = 0;
- memset(bpf_image, 0, sizeof(bpf_image));
-
- if (sscanf(bpf_string, "%hu%c", &bpf_len, &sp) != 2 ||
- sp != separator || bpf_len > BPF_MAXINSNS || bpf_len == 0) {
- rl_printf("syntax error in head length encoding!\n");
- return CMD_ERR;
- }
-
- token = bpf_string;
- while ((token = strchr(token, separator)) && (++token)[0]) {
- if (i >= bpf_len) {
- rl_printf("program exceeds encoded length!\n");
- return CMD_ERR;
- }
-
- if (sscanf(token, "%hu %hhu %hhu %u,",
- &tmp.code, &tmp.jt, &tmp.jf, &tmp.k) != 4) {
- rl_printf("syntax error at instruction %d!\n", i);
- return CMD_ERR;
- }
-
- bpf_image[i].code = tmp.code;
- bpf_image[i].jt = tmp.jt;
- bpf_image[i].jf = tmp.jf;
- bpf_image[i].k = tmp.k;
-
- i++;
- }
-
- if (i != bpf_len) {
- rl_printf("syntax error exceeding encoded length!\n");
- return CMD_ERR;
- } else
- bpf_prog_len = bpf_len;
- if (!bpf_runnable(bpf_image, bpf_prog_len))
- bpf_prog_len = 0;
-
- return CMD_OK;
-}
-
-static int cmd_load_pcap(char *file)
-{
- char *file_trim, *tmp;
-
- file_trim = strtok_r(file, " ", &tmp);
- if (file_trim == NULL)
- return CMD_ERR;
-
- try_close_pcap();
-
- return try_load_pcap(file_trim);
-}
-
-static int cmd_load(char *arg)
-{
- char *subcmd, *cont, *tmp = strdup(arg);
- int ret = CMD_OK;
-
- subcmd = strtok_r(tmp, " ", &cont);
- if (subcmd == NULL)
- goto out;
- if (matches(subcmd, "bpf") == 0) {
- bpf_reset();
- bpf_reset_breakpoints();
-
- ret = cmd_load_bpf(cont);
- } else if (matches(subcmd, "pcap") == 0) {
- ret = cmd_load_pcap(cont);
- } else {
-out:
- rl_printf("bpf <code>: load bpf code\n");
- rl_printf("pcap <file>: load pcap file\n");
- ret = CMD_ERR;
- }
-
- free(tmp);
- return ret;
-}
-
-static int cmd_step(char *num)
-{
- struct pcap_pkthdr *hdr;
- int steps, ret;
-
- if (!bpf_prog_loaded() || !pcap_loaded())
- return CMD_ERR;
-
- steps = strtol(num, NULL, 10);
- if (steps == 0 || strlen(num) == 0)
- steps = 1;
- if (steps < 0) {
- if (!bpf_restore_regs(steps))
- return CMD_ERR;
- steps = 1;
- }
-
- hdr = pcap_curr_pkt();
- ret = bpf_run_stepping(bpf_image, bpf_prog_len,
- (uint8_t *) hdr + sizeof(*hdr),
- hdr->caplen, hdr->len, steps);
- if (ret >= 0 || bpf_curr.Rs) {
- bpf_reset();
- if (!pcap_next_pkt()) {
- rl_printf("(going back to first packet)\n");
- pcap_reset_pkt();
- } else {
- rl_printf("(next packet)\n");
- }
- }
-
- return CMD_OK;
-}
-
-static int cmd_select(char *num)
-{
- unsigned int which, i;
- bool have_next = true;
-
- if (!pcap_loaded() || strlen(num) == 0)
- return CMD_ERR;
-
- which = strtoul(num, NULL, 10);
- if (which == 0) {
- rl_printf("packet count starts with 1, clamping!\n");
- which = 1;
- }
-
- pcap_reset_pkt();
- bpf_reset();
-
- for (i = 0; i < which && (have_next = pcap_next_pkt()); i++)
- /* noop */;
- if (!have_next || pcap_curr_pkt() == NULL) {
- rl_printf("no packet #%u available!\n", which);
- pcap_reset_pkt();
- return CMD_ERR;
- }
-
- return CMD_OK;
-}
-
-static int cmd_breakpoint(char *subcmd)
-{
- if (!bpf_prog_loaded())
- return CMD_ERR;
- if (strlen(subcmd) == 0)
- bpf_dump_breakpoints();
- else if (matches(subcmd, "reset") == 0)
- bpf_reset_breakpoints();
- else {
- unsigned int where = strtoul(subcmd, NULL, 10);
-
- if (where < bpf_prog_len) {
- bpf_set_breakpoints(where);
- rl_printf("breakpoint at: ");
- bpf_disasm(bpf_image[where], where);
- }
- }
-
- return CMD_OK;
-}
-
-static int cmd_run(char *num)
-{
- static uint32_t pass, fail;
- bool has_limit = true;
- int pkts = 0, i = 0;
-
- if (!bpf_prog_loaded() || !pcap_loaded())
- return CMD_ERR;
-
- pkts = strtol(num, NULL, 10);
- if (pkts == 0 || strlen(num) == 0)
- has_limit = false;
-
- do {
- struct pcap_pkthdr *hdr = pcap_curr_pkt();
- int ret = bpf_run_all(bpf_image, bpf_prog_len,
- (uint8_t *) hdr + sizeof(*hdr),
- hdr->caplen, hdr->len);
- if (ret > 0)
- pass++;
- else if (ret == 0)
- fail++;
- else
- return CMD_OK;
- bpf_reset();
- } while (pcap_next_pkt() && (!has_limit || (has_limit && ++i < pkts)));
-
- rl_printf("bpf passes:%u fails:%u\n", pass, fail);
-
- pcap_reset_pkt();
- bpf_reset();
-
- pass = fail = 0;
- return CMD_OK;
-}
-
-static int cmd_disassemble(char *line_string)
-{
- bool single_line = false;
- unsigned long line;
-
- if (!bpf_prog_loaded())
- return CMD_ERR;
- if (strlen(line_string) > 0 &&
- (line = strtoul(line_string, NULL, 10)) < bpf_prog_len)
- single_line = true;
- if (single_line)
- bpf_disasm(bpf_image[line], line);
- else
- bpf_disasm_all(bpf_image, bpf_prog_len);
-
- return CMD_OK;
-}
-
-static int cmd_dump(char *dontcare)
-{
- if (!bpf_prog_loaded())
- return CMD_ERR;
-
- bpf_dump_all(bpf_image, bpf_prog_len);
-
- return CMD_OK;
-}
-
-static int cmd_quit(char *dontcare)
-{
- return CMD_EX;
-}
-
-static const struct shell_cmd cmds[] = {
- { .name = "load", .func = cmd_load },
- { .name = "select", .func = cmd_select },
- { .name = "step", .func = cmd_step },
- { .name = "run", .func = cmd_run },
- { .name = "breakpoint", .func = cmd_breakpoint },
- { .name = "disassemble", .func = cmd_disassemble },
- { .name = "dump", .func = cmd_dump },
- { .name = "quit", .func = cmd_quit },
-};
-
-static int execf(char *arg)
-{
- char *cmd, *cont, *tmp = strdup(arg);
- int i, ret = 0, len;
-
- cmd = strtok_r(tmp, " ", &cont);
- if (cmd == NULL)
- goto out;
- len = strlen(cmd);
- for (i = 0; i < array_size(cmds); i++) {
- if (len != strlen(cmds[i].name))
- continue;
- if (strncmp(cmds[i].name, cmd, len) == 0) {
- ret = cmds[i].func(cont);
- break;
- }
- }
-out:
- free(tmp);
- return ret;
-}
-
-static char *shell_comp_gen(const char *buf, int state)
-{
- static int list_index, len;
-
- if (!state) {
- list_index = 0;
- len = strlen(buf);
- }
-
- for (; list_index < array_size(cmds); ) {
- const char *name = cmds[list_index].name;
-
- list_index++;
- if (strncmp(name, buf, len) == 0)
- return strdup(name);
- }
-
- return NULL;
-}
-
-static char **shell_completion(const char *buf, int start, int end)
-{
- char **matches = NULL;
-
- if (start == 0)
- matches = rl_completion_matches(buf, shell_comp_gen);
-
- return matches;
-}
-
-static void intr_shell(int sig)
-{
- if (rl_end)
- rl_kill_line(-1, 0);
-
- rl_crlf();
- rl_refresh_line(0, 0);
- rl_free_line_state();
-}
-
-static void init_shell(FILE *fin, FILE *fout)
-{
- char file[128];
-
- snprintf(file, sizeof(file), "%s/.bpf_dbg_history", getenv("HOME"));
- read_history(file);
-
- rl_instream = fin;
- rl_outstream = fout;
-
- rl_readline_name = "bpf_dbg";
- rl_terminal_name = getenv("TERM");
-
- rl_catch_signals = 0;
- rl_catch_sigwinch = 1;
-
- rl_attempted_completion_function = shell_completion;
-
- rl_bind_key('\t', rl_complete);
-
- rl_bind_key_in_map('\t', rl_complete, emacs_meta_keymap);
- rl_bind_key_in_map('\033', rl_complete, emacs_meta_keymap);
-
- snprintf(file, sizeof(file), "%s/.bpf_dbg_init", getenv("HOME"));
- rl_read_init_file(file);
-
- rl_prep_terminal(0);
- rl_set_signals();
-
- signal(SIGINT, intr_shell);
-}
-
-static void exit_shell(FILE *fin, FILE *fout)
-{
- char file[128];
-
- snprintf(file, sizeof(file), "%s/.bpf_dbg_history", getenv("HOME"));
- write_history(file);
-
- clear_history();
- rl_deprep_terminal();
-
- try_close_pcap();
-
- if (fin != stdin)
- fclose(fin);
- if (fout != stdout)
- fclose(fout);
-}
-
-static int run_shell_loop(FILE *fin, FILE *fout)
-{
- char *buf;
-
- init_shell(fin, fout);
-
- while ((buf = readline("> ")) != NULL) {
- int ret = execf(buf);
- if (ret == CMD_EX)
- break;
- if (ret == CMD_OK && strlen(buf) > 0)
- add_history(buf);
-
- free(buf);
- }
-
- exit_shell(fin, fout);
- return 0;
-}
-
-int main(int argc, char **argv)
-{
- FILE *fin = NULL, *fout = NULL;
-
- if (argc >= 2)
- fin = fopen(argv[1], "r");
- if (argc >= 3)
- fout = fopen(argv[2], "w");
-
- return run_shell_loop(fin ? : stdin, fout ? : stdout);
-}