ASR_BASE
Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/marvell/linux/tools/bpf/bpf_jit_disasm.c b/marvell/linux/tools/bpf/bpf_jit_disasm.c
new file mode 100644
index 0000000..c8ae958
--- /dev/null
+++ b/marvell/linux/tools/bpf/bpf_jit_disasm.c
@@ -0,0 +1,329 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Minimal BPF JIT image disassembler
+ *
+ * Disassembles BPF JIT compiler emitted opcodes back to asm insn's for
+ * debugging or verification purposes.
+ *
+ * To get the disassembly of the JIT code, do the following:
+ *
+ * 1) `echo 2 > /proc/sys/net/core/bpf_jit_enable`
+ * 2) Load a BPF filter (e.g. `tcpdump -p -n -s 0 -i eth1 host 192.168.20.0/24`)
+ * 3) Run e.g. `bpf_jit_disasm -o` to read out the last JIT code
+ *
+ * Copyright 2013 Daniel Borkmann <borkmann@redhat.com>
+ */
+
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <assert.h>
+#include <unistd.h>
+#include <string.h>
+#include <bfd.h>
+#include <dis-asm.h>
+#include <regex.h>
+#include <fcntl.h>
+#include <sys/klog.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <limits.h>
+
+#define CMD_ACTION_SIZE_BUFFER 10
+#define CMD_ACTION_READ_ALL 3
+
+static void get_exec_path(char *tpath, size_t size)
+{
+ char *path;
+ ssize_t len;
+
+ snprintf(tpath, size, "/proc/%d/exe", (int) getpid());
+ tpath[size - 1] = 0;
+
+ path = strdup(tpath);
+ assert(path);
+
+ len = readlink(path, tpath, size);
+ tpath[len] = 0;
+
+ free(path);
+}
+
+static void get_asm_insns(uint8_t *image, size_t len, int opcodes)
+{
+ int count, i, pc = 0;
+ char tpath[PATH_MAX];
+ struct disassemble_info info;
+ disassembler_ftype disassemble;
+ bfd *bfdf;
+
+ memset(tpath, 0, sizeof(tpath));
+ get_exec_path(tpath, sizeof(tpath));
+
+ bfdf = bfd_openr(tpath, NULL);
+ assert(bfdf);
+ assert(bfd_check_format(bfdf, bfd_object));
+
+ init_disassemble_info(&info, stdout, (fprintf_ftype) fprintf);
+ info.arch = bfd_get_arch(bfdf);
+ info.mach = bfd_get_mach(bfdf);
+ info.buffer = image;
+ info.buffer_length = len;
+
+ disassemble_init_for_target(&info);
+
+#ifdef DISASM_FOUR_ARGS_SIGNATURE
+ disassemble = disassembler(info.arch,
+ bfd_big_endian(bfdf),
+ info.mach,
+ bfdf);
+#else
+ disassemble = disassembler(bfdf);
+#endif
+ assert(disassemble);
+
+ do {
+ printf("%4x:\t", pc);
+
+ count = disassemble(pc, &info);
+
+ if (opcodes) {
+ printf("\n\t");
+ for (i = 0; i < count; ++i)
+ printf("%02x ", (uint8_t) image[pc + i]);
+ }
+ printf("\n");
+
+ pc += count;
+ } while(count > 0 && pc < len);
+
+ bfd_close(bfdf);
+}
+
+static char *get_klog_buff(unsigned int *klen)
+{
+ int ret, len;
+ char *buff;
+
+ len = klogctl(CMD_ACTION_SIZE_BUFFER, NULL, 0);
+ if (len < 0)
+ return NULL;
+
+ buff = malloc(len);
+ if (!buff)
+ return NULL;
+
+ ret = klogctl(CMD_ACTION_READ_ALL, buff, len);
+ if (ret < 0) {
+ free(buff);
+ return NULL;
+ }
+
+ *klen = ret;
+ return buff;
+}
+
+static char *get_flog_buff(const char *file, unsigned int *klen)
+{
+ int fd, ret, len;
+ struct stat fi;
+ char *buff;
+
+ fd = open(file, O_RDONLY);
+ if (fd < 0)
+ return NULL;
+
+ ret = fstat(fd, &fi);
+ if (ret < 0 || !S_ISREG(fi.st_mode))
+ goto out;
+
+ len = fi.st_size + 1;
+ buff = malloc(len);
+ if (!buff)
+ goto out;
+
+ memset(buff, 0, len);
+ ret = read(fd, buff, len - 1);
+ if (ret <= 0)
+ goto out_free;
+
+ close(fd);
+ *klen = ret;
+ return buff;
+out_free:
+ free(buff);
+out:
+ close(fd);
+ return NULL;
+}
+
+static char *get_log_buff(const char *file, unsigned int *klen)
+{
+ return file ? get_flog_buff(file, klen) : get_klog_buff(klen);
+}
+
+static void put_log_buff(char *buff)
+{
+ free(buff);
+}
+
+static uint8_t *get_last_jit_image(char *haystack, size_t hlen,
+ unsigned int *ilen)
+{
+ char *ptr, *pptr, *tmp;
+ off_t off = 0;
+ unsigned int proglen;
+ int ret, flen, pass, ulen = 0;
+ regmatch_t pmatch[1];
+ unsigned long base;
+ regex_t regex;
+ uint8_t *image;
+
+ if (hlen == 0)
+ return NULL;
+
+ ret = regcomp(®ex, "flen=[[:alnum:]]+ proglen=[[:digit:]]+ "
+ "pass=[[:digit:]]+ image=[[:xdigit:]]+", REG_EXTENDED);
+ assert(ret == 0);
+
+ ptr = haystack;
+ memset(pmatch, 0, sizeof(pmatch));
+
+ while (1) {
+ ret = regexec(®ex, ptr, 1, pmatch, 0);
+ if (ret == 0) {
+ ptr += pmatch[0].rm_eo;
+ off += pmatch[0].rm_eo;
+ assert(off < hlen);
+ } else
+ break;
+ }
+
+ ptr = haystack + off - (pmatch[0].rm_eo - pmatch[0].rm_so);
+ ret = sscanf(ptr, "flen=%d proglen=%u pass=%d image=%lx",
+ &flen, &proglen, &pass, &base);
+ if (ret != 4) {
+ regfree(®ex);
+ return NULL;
+ }
+ if (proglen > 1000000) {
+ printf("proglen of %d too big, stopping\n", proglen);
+ return NULL;
+ }
+
+ image = malloc(proglen);
+ if (!image) {
+ printf("Out of memory\n");
+ return NULL;
+ }
+ memset(image, 0, proglen);
+
+ tmp = ptr = haystack + off;
+ while ((ptr = strtok(tmp, "\n")) != NULL && ulen < proglen) {
+ tmp = NULL;
+ if (!strstr(ptr, "JIT code"))
+ continue;
+ pptr = ptr;
+ while ((ptr = strstr(pptr, ":")))
+ pptr = ptr + 1;
+ ptr = pptr;
+ do {
+ image[ulen++] = (uint8_t) strtoul(pptr, &pptr, 16);
+ if (ptr == pptr) {
+ ulen--;
+ break;
+ }
+ if (ulen >= proglen)
+ break;
+ ptr = pptr;
+ } while (1);
+ }
+
+ assert(ulen == proglen);
+ printf("%u bytes emitted from JIT compiler (pass:%d, flen:%d)\n",
+ proglen, pass, flen);
+ printf("%lx + <x>:\n", base);
+
+ regfree(®ex);
+ *ilen = ulen;
+ return image;
+}
+
+static void usage(void)
+{
+ printf("Usage: bpf_jit_disasm [...]\n");
+ printf(" -o Also display related opcodes (default: off).\n");
+ printf(" -O <file> Write binary image of code to file, don't disassemble to stdout.\n");
+ printf(" -f <file> Read last image dump from file or stdin (default: klog).\n");
+ printf(" -h Display this help.\n");
+}
+
+int main(int argc, char **argv)
+{
+ unsigned int len, klen, opt, opcodes = 0;
+ char *kbuff, *file = NULL;
+ char *ofile = NULL;
+ int ofd;
+ ssize_t nr;
+ uint8_t *pos;
+ uint8_t *image = NULL;
+
+ while ((opt = getopt(argc, argv, "of:O:")) != -1) {
+ switch (opt) {
+ case 'o':
+ opcodes = 1;
+ break;
+ case 'O':
+ ofile = optarg;
+ break;
+ case 'f':
+ file = optarg;
+ break;
+ default:
+ usage();
+ return -1;
+ }
+ }
+
+ bfd_init();
+
+ kbuff = get_log_buff(file, &klen);
+ if (!kbuff) {
+ fprintf(stderr, "Could not retrieve log buffer!\n");
+ return -1;
+ }
+
+ image = get_last_jit_image(kbuff, klen, &len);
+ if (!image) {
+ fprintf(stderr, "No JIT image found!\n");
+ goto done;
+ }
+ if (!ofile) {
+ get_asm_insns(image, len, opcodes);
+ goto done;
+ }
+
+ ofd = open(ofile, O_WRONLY | O_CREAT | O_TRUNC, DEFFILEMODE);
+ if (ofd < 0) {
+ fprintf(stderr, "Could not open file %s for writing: ", ofile);
+ perror(NULL);
+ goto done;
+ }
+ pos = image;
+ do {
+ nr = write(ofd, pos, len);
+ if (nr < 0) {
+ fprintf(stderr, "Could not write data to %s: ", ofile);
+ perror(NULL);
+ goto done;
+ }
+ len -= nr;
+ pos += nr;
+ } while (len);
+ close(ofd);
+
+done:
+ put_log_buff(kbuff);
+ free(image);
+ return 0;
+}