Squashed 'third_party/elfutils/' content from commit 555e15e
Change-Id: I61cde98949e47e5c8c09c33260de17f30921be79
git-subtree-dir: third_party/elfutils
git-subtree-split: 555e15ebe8bf1eb33d00747173cfc80cc65648a4
diff --git a/libcpu/bpf_disasm.c b/libcpu/bpf_disasm.c
new file mode 100644
index 0000000..054aba2
--- /dev/null
+++ b/libcpu/bpf_disasm.c
@@ -0,0 +1,480 @@
+/* Disassembler for BPF.
+ Copyright (C) 2016 Red Hat, Inc.
+ This file is part of elfutils.
+
+ This file is free software; you can redistribute it and/or modify
+ it under the terms of either
+
+ * the GNU Lesser General Public License as published by the Free
+ Software Foundation; either version 3 of the License, or (at
+ your option) any later version
+
+ or
+
+ * 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
+
+ or both in parallel, as here.
+
+ elfutils is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ General Public License for more details.
+
+ You should have received copies of the GNU General Public License and
+ the GNU Lesser General Public License along with this program. If
+ not, see <http://www.gnu.org/licenses/>. */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <assert.h>
+#include <string.h>
+#include <stdio.h>
+#include <gelf.h>
+#include <inttypes.h>
+#include "bpf.h"
+
+#include "../libelf/common.h"
+#include "../libebl/libeblP.h"
+
+static const char class_string[8][8] = {
+ [BPF_LD] = "ld",
+ [BPF_LDX] = "ldx",
+ [BPF_ST] = "st",
+ [BPF_STX] = "stx",
+ [BPF_ALU] = "alu",
+ [BPF_JMP] = "jmp",
+ [BPF_RET] = "6", /* completely unused in ebpf */
+ [BPF_ALU64] = "alu64",
+};
+
+
+#define REG(N) "r%" #N "$d"
+#define REGU(N) "(u32)" REG(N)
+#define REGS(N) "(s64)" REG(N)
+
+#define IMMS(N) "%" #N "$d"
+#define IMMX(N) "%" #N "$#x"
+
+#define OFF(N) "%" #N "$+d"
+#define JMP(N) "%" #N "$#x"
+
+#define A32(O, S) REG(1) " = " REGU(1) " " #O " " S
+#define A64(O, S) REG(1) " " #O "= " S
+#define J64(D, O, S) "if " D " " #O " " S " goto " JMP(3)
+#define LOAD(T) REG(1) " = *(" #T " *)(" REG(2) OFF(3) ")"
+#define STORE(T, S) "*(" #T " *)(" REG(1) OFF(3) ") = " S
+#define XADD(T, S) "lock *(" #T " *)(" REG(1) OFF(3) ") += " S
+#define LDSKB(T, S) "r0 = *(" #T " *)skb[" S "]"
+
+static void
+bswap_bpf_insn (struct bpf_insn *p)
+{
+ /* Note that the dst_reg and src_reg fields are 4-bit bitfields.
+ That means these two nibbles are (typically) layed out in the
+ opposite order between big- and little-endian hosts. This is
+ not required by any standard, but does happen to be true for
+ at least ppc, s390, arm and mips as big-endian hosts. */
+ int t = p->dst_reg;
+ p->dst_reg = p->src_reg;
+ p->src_reg = t;
+
+ /* The other 2 and 4 byte fields are trivially converted. */
+ CONVERT (p->off);
+ CONVERT (p->imm);
+}
+
+int
+bpf_disasm (Ebl *ebl, const uint8_t **startp, const uint8_t *end,
+ GElf_Addr addr, const char *fmt __attribute__((unused)),
+ DisasmOutputCB_t outcb,
+ DisasmGetSymCB_t symcb __attribute__((unused)),
+ void *outcbarg,
+ void *symcbarg __attribute__((unused)))
+{
+ const bool need_bswap = MY_ELFDATA != ebl->data;
+ const uint8_t *start = *startp;
+ char buf[128];
+ int len, retval = 0;
+
+ while (start + sizeof(struct bpf_insn) <= end)
+ {
+ struct bpf_insn i;
+ unsigned code, class, jmp;
+ const char *code_fmt;
+
+ memcpy(&i, start, sizeof(struct bpf_insn));
+ if (need_bswap)
+ bswap_bpf_insn (&i);
+
+ start += sizeof(struct bpf_insn);
+ addr += sizeof(struct bpf_insn);
+ jmp = addr + i.off * sizeof(struct bpf_insn);
+
+ code = i.code;
+ switch (code)
+ {
+ case BPF_LD | BPF_IMM | BPF_DW:
+ {
+ struct bpf_insn i2;
+ uint64_t imm64;
+
+ if (start + sizeof(struct bpf_insn) > end)
+ {
+ start -= sizeof(struct bpf_insn);
+ *startp = start;
+ goto done;
+ }
+ memcpy(&i2, start, sizeof(struct bpf_insn));
+ if (need_bswap)
+ bswap_bpf_insn (&i2);
+ start += sizeof(struct bpf_insn);
+ addr += sizeof(struct bpf_insn);
+
+ imm64 = (uint32_t)i.imm | ((uint64_t)i2.imm << 32);
+ switch (i.src_reg)
+ {
+ case 0:
+ code_fmt = REG(1) " = %2$#" PRIx64;
+ break;
+ case BPF_PSEUDO_MAP_FD:
+ code_fmt = REG(1) " = map_fd(%2$#" PRIx64 ")";
+ break;
+ default:
+ code_fmt = REG(1) " = ld_pseudo(%3$d, %2$#" PRIx64 ")";
+ break;
+ }
+ len = snprintf(buf, sizeof(buf), code_fmt,
+ i.dst_reg, imm64, i.src_reg);
+ }
+ break;
+
+ case BPF_JMP | BPF_EXIT:
+ len = snprintf(buf, sizeof(buf), "exit");
+ break;
+ case BPF_JMP | BPF_JA:
+ len = snprintf(buf, sizeof(buf), "goto " JMP(1), jmp);
+ break;
+ case BPF_JMP | BPF_CALL:
+ code_fmt = "call " IMMS(1);
+ goto do_imm;
+
+ case BPF_ALU | BPF_END | BPF_TO_LE:
+ /* The imm field contains {16,32,64}. */
+ code_fmt = REG(1) " = le" IMMS(2) "(" REG(1) ")";
+ goto do_dst_imm;
+ case BPF_ALU | BPF_END | BPF_TO_BE:
+ code_fmt = REG(1) " = be" IMMS(2) "(" REG(1) ")";
+ goto do_dst_imm;
+
+ case BPF_ALU | BPF_ADD | BPF_K:
+ code_fmt = A32(+, IMMS(2));
+ goto do_dst_imm;
+ case BPF_ALU | BPF_SUB | BPF_K:
+ code_fmt = A32(-, IMMS(2));
+ goto do_dst_imm;
+ case BPF_ALU | BPF_MUL | BPF_K:
+ code_fmt = A32(*, IMMS(2));
+ goto do_dst_imm;
+ case BPF_ALU | BPF_DIV | BPF_K:
+ code_fmt = A32(/, IMMS(2));
+ goto do_dst_imm;
+ case BPF_ALU | BPF_OR | BPF_K:
+ code_fmt = A32(|, IMMX(2));
+ goto do_dst_imm;
+ case BPF_ALU | BPF_AND | BPF_K:
+ code_fmt = A32(&, IMMX(2));
+ goto do_dst_imm;
+ case BPF_ALU | BPF_LSH | BPF_K:
+ code_fmt = A32(<<, IMMS(2));
+ goto do_dst_imm;
+ case BPF_ALU | BPF_RSH | BPF_K:
+ code_fmt = A32(>>, IMMS(2));
+ goto do_dst_imm;
+ case BPF_ALU | BPF_MOD | BPF_K:
+ code_fmt = A32(%%, IMMS(2));
+ goto do_dst_imm;
+ case BPF_ALU | BPF_XOR | BPF_K:
+ code_fmt = A32(^, IMMX(2));
+ goto do_dst_imm;
+ case BPF_ALU | BPF_MOV | BPF_K:
+ code_fmt = REG(1) " = " IMMX(2);
+ goto do_dst_imm;
+ case BPF_ALU | BPF_ARSH | BPF_K:
+ code_fmt = REG(1) " = (u32)((s32)" REG(1) " >> " IMMS(2) ")";
+ goto do_dst_imm;
+
+ case BPF_ALU | BPF_ADD | BPF_X:
+ code_fmt = A32(+, REGU(2));
+ goto do_dst_src;
+ case BPF_ALU | BPF_SUB | BPF_X:
+ code_fmt = A32(-, REGU(2));
+ goto do_dst_src;
+ case BPF_ALU | BPF_MUL | BPF_X:
+ code_fmt = A32(*, REGU(2));
+ goto do_dst_src;
+ case BPF_ALU | BPF_DIV | BPF_X:
+ code_fmt = A32(/, REGU(2));
+ goto do_dst_src;
+ case BPF_ALU | BPF_OR | BPF_X:
+ code_fmt = A32(|, REGU(2));
+ goto do_dst_src;
+ case BPF_ALU | BPF_AND | BPF_X:
+ code_fmt = A32(&, REGU(2));
+ goto do_dst_src;
+ case BPF_ALU | BPF_LSH | BPF_X:
+ code_fmt = A32(<<, REGU(2));
+ goto do_dst_src;
+ case BPF_ALU | BPF_RSH | BPF_X:
+ code_fmt = A32(>>, REGU(2));
+ goto do_dst_src;
+ case BPF_ALU | BPF_MOD | BPF_X:
+ code_fmt = A32(%%, REGU(2));
+ goto do_dst_src;
+ case BPF_ALU | BPF_XOR | BPF_X:
+ code_fmt = A32(^, REGU(2));
+ goto do_dst_src;
+ case BPF_ALU | BPF_MOV | BPF_X:
+ code_fmt = REG(1) " = " REGU(2);
+ goto do_dst_src;
+ case BPF_ALU | BPF_ARSH | BPF_X:
+ code_fmt = REG(1) " = (u32)((s32)" REG(1) " >> " REG(2) ")";
+ goto do_dst_src;
+
+ case BPF_ALU64 | BPF_ADD | BPF_K:
+ code_fmt = A64(+, IMMS(2));
+ goto do_dst_imm;
+ case BPF_ALU64 | BPF_SUB | BPF_K:
+ code_fmt = A64(-, IMMS(2));
+ goto do_dst_imm;
+ case BPF_ALU64 | BPF_MUL | BPF_K:
+ code_fmt = A64(*, IMMS(2));
+ goto do_dst_imm;
+ case BPF_ALU64 | BPF_DIV | BPF_K:
+ code_fmt = A64(/, IMMS(2));
+ goto do_dst_imm;
+ case BPF_ALU64 | BPF_OR | BPF_K:
+ code_fmt = A64(|, IMMS(2));
+ goto do_dst_imm;
+ case BPF_ALU64 | BPF_AND | BPF_K:
+ code_fmt = A64(&, IMMS(2));
+ goto do_dst_imm;
+ case BPF_ALU64 | BPF_LSH | BPF_K:
+ code_fmt = A64(<<, IMMS(2));
+ goto do_dst_imm;
+ case BPF_ALU64 | BPF_RSH | BPF_K:
+ code_fmt = A64(>>, IMMS(2));
+ goto do_dst_imm;
+ case BPF_ALU64 | BPF_MOD | BPF_K:
+ code_fmt = A64(%%, IMMS(2));
+ goto do_dst_imm;
+ case BPF_ALU64 | BPF_XOR | BPF_K:
+ code_fmt = A64(^, IMMS(2));
+ goto do_dst_imm;
+ case BPF_ALU64 | BPF_MOV | BPF_K:
+ code_fmt = REG(1) " = " IMMS(2);
+ goto do_dst_imm;
+ case BPF_ALU64 | BPF_ARSH | BPF_K:
+ code_fmt = REG(1) " = (s64)" REG(1) " >> " IMMS(2);
+ goto do_dst_imm;
+
+ case BPF_ALU64 | BPF_ADD | BPF_X:
+ code_fmt = A64(+, REG(2));
+ goto do_dst_src;
+ case BPF_ALU64 | BPF_SUB | BPF_X:
+ code_fmt = A64(-, REG(2));
+ goto do_dst_src;
+ case BPF_ALU64 | BPF_MUL | BPF_X:
+ code_fmt = A64(*, REG(2));
+ goto do_dst_src;
+ case BPF_ALU64 | BPF_DIV | BPF_X:
+ code_fmt = A64(/, REG(2));
+ goto do_dst_src;
+ case BPF_ALU64 | BPF_OR | BPF_X:
+ code_fmt = A64(|, REG(2));
+ goto do_dst_src;
+ case BPF_ALU64 | BPF_AND | BPF_X:
+ code_fmt = A64(&, REG(2));
+ goto do_dst_src;
+ case BPF_ALU64 | BPF_LSH | BPF_X:
+ code_fmt = A64(<<, REG(2));
+ goto do_dst_src;
+ case BPF_ALU64 | BPF_RSH | BPF_X:
+ code_fmt = A64(>>, REG(2));
+ goto do_dst_src;
+ case BPF_ALU64 | BPF_MOD | BPF_X:
+ code_fmt = A64(%%, REG(2));
+ goto do_dst_src;
+ case BPF_ALU64 | BPF_XOR | BPF_X:
+ code_fmt = A64(^, REG(2));
+ goto do_dst_src;
+ case BPF_ALU64 | BPF_MOV | BPF_X:
+ code_fmt = REG(1) " = " REG(2);
+ goto do_dst_src;
+ case BPF_ALU64 | BPF_ARSH | BPF_X:
+ code_fmt = REG(1) " = (s64)" REG(1) " >> " REG(2);
+ goto do_dst_src;
+
+ case BPF_ALU | BPF_NEG:
+ code_fmt = REG(1) " = (u32)-" REG(1);
+ goto do_dst_src;
+ case BPF_ALU64 | BPF_NEG:
+ code_fmt = REG(1) " = -" REG(1);
+ goto do_dst_src;
+
+ case BPF_JMP | BPF_JEQ | BPF_K:
+ code_fmt = J64(REG(1), ==, IMMS(2));
+ goto do_dst_imm_jmp;
+ case BPF_JMP | BPF_JGT | BPF_K:
+ code_fmt = J64(REG(1), >, IMMS(2));
+ goto do_dst_imm_jmp;
+ case BPF_JMP | BPF_JGE | BPF_K:
+ code_fmt = J64(REG(1), >=, IMMS(2));
+ goto do_dst_imm_jmp;
+ case BPF_JMP | BPF_JSET | BPF_K:
+ code_fmt = J64(REG(1), &, IMMS(2));
+ goto do_dst_imm_jmp;
+ case BPF_JMP | BPF_JNE | BPF_K:
+ code_fmt = J64(REG(1), !=, IMMS(2));
+ goto do_dst_imm_jmp;
+ case BPF_JMP | BPF_JSGT | BPF_K:
+ code_fmt = J64(REGS(1), >, IMMS(2));
+ goto do_dst_imm_jmp;
+ case BPF_JMP | BPF_JSGE | BPF_K:
+ code_fmt = J64(REGS(1), >=, IMMS(2));
+ goto do_dst_imm_jmp;
+
+ case BPF_JMP | BPF_JEQ | BPF_X:
+ code_fmt = J64(REG(1), ==, REG(2));
+ goto do_dst_src_jmp;
+ case BPF_JMP | BPF_JGT | BPF_X:
+ code_fmt = J64(REG(1), >, REG(2));
+ goto do_dst_src_jmp;
+ case BPF_JMP | BPF_JGE | BPF_X:
+ code_fmt = J64(REG(1), >=, REG(2));
+ goto do_dst_src_jmp;
+ case BPF_JMP | BPF_JSET | BPF_X:
+ code_fmt = J64(REG(1), &, REG(2));
+ goto do_dst_src_jmp;
+ case BPF_JMP | BPF_JNE | BPF_X:
+ code_fmt = J64(REG(1), !=, REG(2));
+ goto do_dst_src_jmp;
+ case BPF_JMP | BPF_JSGT | BPF_X:
+ code_fmt = J64(REGS(1), >, REGS(2));
+ goto do_dst_src_jmp;
+ case BPF_JMP | BPF_JSGE | BPF_X:
+ code_fmt = J64(REGS(1), >=, REGS(2));
+ goto do_dst_src_jmp;
+
+ case BPF_LDX | BPF_MEM | BPF_B:
+ code_fmt = LOAD(u8);
+ goto do_dst_src_off;
+ case BPF_LDX | BPF_MEM | BPF_H:
+ code_fmt = LOAD(u16);
+ goto do_dst_src_off;
+ case BPF_LDX | BPF_MEM | BPF_W:
+ code_fmt = LOAD(u32);
+ goto do_dst_src_off;
+ case BPF_LDX | BPF_MEM | BPF_DW:
+ code_fmt = LOAD(u64);
+ goto do_dst_src_off;
+
+ case BPF_STX | BPF_MEM | BPF_B:
+ code_fmt = STORE(u8, REG(2));
+ goto do_dst_src_off;
+ case BPF_STX | BPF_MEM | BPF_H:
+ code_fmt = STORE(u16, REG(2));
+ goto do_dst_src_off;
+ case BPF_STX | BPF_MEM | BPF_W:
+ code_fmt = STORE(u32, REG(2));
+ goto do_dst_src_off;
+ case BPF_STX | BPF_MEM | BPF_DW:
+ code_fmt = STORE(u64, REG(2));
+ goto do_dst_src_off;
+
+ case BPF_STX | BPF_XADD | BPF_W:
+ code_fmt = XADD(u32, REG(2));
+ goto do_dst_src_off;
+ case BPF_STX | BPF_XADD | BPF_DW:
+ code_fmt = XADD(u64, REG(2));
+ goto do_dst_src_off;
+
+ case BPF_ST | BPF_MEM | BPF_B:
+ code_fmt = STORE(u8, IMMS(2));
+ goto do_dst_imm_off;
+ case BPF_ST | BPF_MEM | BPF_H:
+ code_fmt = STORE(u16, IMMS(2));
+ goto do_dst_imm_off;
+ case BPF_ST | BPF_MEM | BPF_W:
+ code_fmt = STORE(u32, IMMS(2));
+ goto do_dst_imm_off;
+ case BPF_ST | BPF_MEM | BPF_DW:
+ code_fmt = STORE(u64, IMMS(2));
+ goto do_dst_imm_off;
+
+ case BPF_LD | BPF_ABS | BPF_B:
+ code_fmt = LDSKB(u8, IMMS(1));
+ goto do_imm;
+ case BPF_LD | BPF_ABS | BPF_H:
+ code_fmt = LDSKB(u16, IMMS(1));
+ goto do_imm;
+ case BPF_LD | BPF_ABS | BPF_W:
+ code_fmt = LDSKB(u32, IMMS(1));
+ goto do_imm;
+
+ case BPF_LD | BPF_IND | BPF_B:
+ code_fmt = LDSKB(u8, REG(1) "+" IMMS(2));
+ goto do_src_imm;
+ case BPF_LD | BPF_IND | BPF_H:
+ code_fmt = LDSKB(u16, REG(1) "+" IMMS(2));
+ goto do_src_imm;
+ case BPF_LD | BPF_IND | BPF_W:
+ code_fmt = LDSKB(u32, REG(1) "+" IMMS(2));
+ goto do_src_imm;
+
+ do_imm:
+ len = snprintf(buf, sizeof(buf), code_fmt, i.imm);
+ break;
+ do_dst_imm:
+ len = snprintf(buf, sizeof(buf), code_fmt, i.dst_reg, i.imm);
+ break;
+ do_src_imm:
+ len = snprintf(buf, sizeof(buf), code_fmt, i.src_reg, i.imm);
+ break;
+ do_dst_src:
+ len = snprintf(buf, sizeof(buf), code_fmt, i.dst_reg, i.src_reg);
+ break;
+ do_dst_imm_jmp:
+ len = snprintf(buf, sizeof(buf), code_fmt, i.dst_reg, i.imm, jmp);
+ break;
+ do_dst_src_jmp:
+ len = snprintf(buf, sizeof(buf), code_fmt,
+ i.dst_reg, i.src_reg, jmp);
+ break;
+ do_dst_imm_off:
+ len = snprintf(buf, sizeof(buf), code_fmt, i.dst_reg, i.imm, i.off);
+ break;
+ do_dst_src_off:
+ len = snprintf(buf, sizeof(buf), code_fmt,
+ i.dst_reg, i.src_reg, i.off);
+ break;
+
+ default:
+ class = BPF_CLASS(code);
+ len = snprintf(buf, sizeof(buf), "invalid class %s",
+ class_string[class]);
+ break;
+ }
+
+ *startp = start;
+ retval = outcb (buf, len, outcbarg);
+ if (retval != 0)
+ goto done;
+ }
+
+ done:
+ return retval;
+}