From b901d928361cc6f2ff03909a0f7a18640252ee27 Mon Sep 17 00:00:00 2001 From: Konstantin Ananyev Date: Wed, 27 May 2020 15:16:51 +0100 Subject: [PATCH] bpf: support packet data load instructions To fill the gap with linux kernel eBPF implementation, add support for two non-generic instructions: (BPF_ABS | | BPF_LD) and (BPF_IND | | BPF_LD) which are used to access packet data. These instructions can only be used when BPF context is a pointer to 'struct rte_mbuf' (i.e: RTE_BPF_ARG_PTR_MBUF type). Signed-off-by: Konstantin Ananyev --- app/test/test_bpf.c | 463 +++++++++++++++++++++++++ doc/guides/prog_guide/bpf_lib.rst | 30 +- doc/guides/rel_notes/release_20_08.rst | 7 + lib/librte_bpf/bpf_exec.c | 57 +++ lib/librte_bpf/bpf_validate.c | 77 ++++ 5 files changed, 633 insertions(+), 1 deletion(-) diff --git a/app/test/test_bpf.c b/app/test/test_bpf.c index 4a61a7d7cb..7c3de96c62 100644 --- a/app/test/test_bpf.c +++ b/app/test/test_bpf.c @@ -43,6 +43,14 @@ struct dummy_net { struct rte_ipv4_hdr ip_hdr; }; +#define DUMMY_MBUF_NUM 2 + +/* first mbuf in the packet, should always be at offset 0 */ +struct dummy_mbuf { + struct rte_mbuf mb[DUMMY_MBUF_NUM]; + uint8_t buf[DUMMY_MBUF_NUM][RTE_MBUF_DEFAULT_BUF_SIZE]; +}; + #define TEST_FILL_1 0xDEADBEEF #define TEST_MUL_1 21 @@ -2444,6 +2452,413 @@ static const struct rte_bpf_xsym test_call5_xsym[] = { }, }; +/* load mbuf (BPF_ABS/BPF_IND) test-cases */ +static const struct ebpf_insn test_ld_mbuf1_prog[] = { + + /* BPF_ABS/BPF_IND implicitly expect mbuf ptr in R6 */ + { + .code = (EBPF_ALU64 | EBPF_MOV | BPF_X), + .dst_reg = EBPF_REG_6, + .src_reg = EBPF_REG_1, + }, + /* load IPv4 version and IHL */ + { + .code = (BPF_LD | BPF_ABS | BPF_B), + .imm = offsetof(struct rte_ipv4_hdr, version_ihl), + }, + /* check IP version */ + { + .code = (EBPF_ALU64 | EBPF_MOV | BPF_X), + .dst_reg = EBPF_REG_2, + .src_reg = EBPF_REG_0, + }, + { + .code = (BPF_ALU | BPF_AND | BPF_K), + .dst_reg = EBPF_REG_2, + .imm = 0xf0, + }, + { + .code = (BPF_JMP | BPF_JEQ | BPF_K), + .dst_reg = EBPF_REG_2, + .imm = IPVERSION << 4, + .off = 2, + }, + /* invalid IP version, return 0 */ + { + .code = (EBPF_ALU64 | BPF_XOR | BPF_X), + .dst_reg = EBPF_REG_0, + .src_reg = EBPF_REG_0, + }, + { + .code = (BPF_JMP | EBPF_EXIT), + }, + /* load 3-rd byte of IP data */ + { + .code = (BPF_ALU | BPF_AND | BPF_K), + .dst_reg = EBPF_REG_0, + .imm = RTE_IPV4_HDR_IHL_MASK, + }, + { + .code = (BPF_ALU | BPF_LSH | BPF_K), + .dst_reg = EBPF_REG_0, + .imm = 2, + }, + { + .code = (BPF_LD | BPF_IND | BPF_B), + .src_reg = EBPF_REG_0, + .imm = 3, + }, + { + .code = (EBPF_ALU64 | EBPF_MOV | BPF_X), + .dst_reg = EBPF_REG_7, + .src_reg = EBPF_REG_0, + }, + /* load IPv4 src addr */ + { + .code = (BPF_LD | BPF_ABS | BPF_W), + .imm = offsetof(struct rte_ipv4_hdr, src_addr), + }, + { + .code = (EBPF_ALU64 | BPF_ADD | BPF_X), + .dst_reg = EBPF_REG_7, + .src_reg = EBPF_REG_0, + }, + /* load IPv4 total length */ + { + .code = (BPF_LD | BPF_ABS | BPF_H), + .imm = offsetof(struct rte_ipv4_hdr, total_length), + }, + { + .code = (EBPF_ALU64 | EBPF_MOV | BPF_X), + .dst_reg = EBPF_REG_8, + .src_reg = EBPF_REG_0, + }, + /* load last 4 bytes of IP data */ + { + .code = (BPF_LD | BPF_IND | BPF_W), + .src_reg = EBPF_REG_8, + .imm = -(int32_t)sizeof(uint32_t), + }, + { + .code = (EBPF_ALU64 | BPF_ADD | BPF_X), + .dst_reg = EBPF_REG_7, + .src_reg = EBPF_REG_0, + }, + /* load 2 bytes from the middle of IP data */ + { + .code = (EBPF_ALU64 | BPF_RSH | BPF_K), + .dst_reg = EBPF_REG_8, + .imm = 1, + }, + { + .code = (BPF_LD | BPF_IND | BPF_H), + .src_reg = EBPF_REG_8, + }, + { + .code = (EBPF_ALU64 | BPF_ADD | BPF_X), + .dst_reg = EBPF_REG_0, + .src_reg = EBPF_REG_7, + }, + { + .code = (BPF_JMP | EBPF_EXIT), + }, +}; + +static void +dummy_mbuf_prep(struct rte_mbuf *mb, uint8_t buf[], uint32_t buf_len, + uint32_t data_len) +{ + uint32_t i; + uint8_t *db; + + mb->buf_addr = buf; + mb->buf_iova = (uintptr_t)buf; + mb->buf_len = buf_len; + rte_mbuf_refcnt_set(mb, 1); + + /* set pool pointer to dummy value, test doesn't use it */ + mb->pool = (void *)buf; + + rte_pktmbuf_reset(mb); + db = (uint8_t *)rte_pktmbuf_append(mb, data_len); + + for (i = 0; i != data_len; i++) + db[i] = i; +} + +static void +test_ld_mbuf1_prepare(void *arg) +{ + struct dummy_mbuf *dm; + struct rte_ipv4_hdr *ph; + + const uint32_t plen = 400; + const struct rte_ipv4_hdr iph = { + .version_ihl = RTE_IPV4_VHL_DEF, + .total_length = rte_cpu_to_be_16(plen), + .time_to_live = IPDEFTTL, + .next_proto_id = IPPROTO_RAW, + .src_addr = rte_cpu_to_be_32(RTE_IPV4_LOOPBACK), + .dst_addr = rte_cpu_to_be_32(RTE_IPV4_BROADCAST), + }; + + dm = arg; + memset(dm, 0, sizeof(*dm)); + + dummy_mbuf_prep(&dm->mb[0], dm->buf[0], sizeof(dm->buf[0]), + plen / 2 + 1); + dummy_mbuf_prep(&dm->mb[1], dm->buf[1], sizeof(dm->buf[0]), + plen / 2 - 1); + + rte_pktmbuf_chain(&dm->mb[0], &dm->mb[1]); + + ph = rte_pktmbuf_mtod(dm->mb, typeof(ph)); + memcpy(ph, &iph, sizeof(iph)); +} + +static uint64_t +test_ld_mbuf1(const struct rte_mbuf *pkt) +{ + uint64_t n, v; + const uint8_t *p8; + const uint16_t *p16; + const uint32_t *p32; + struct dummy_offset dof; + + /* load IPv4 version and IHL */ + p8 = rte_pktmbuf_read(pkt, + offsetof(struct rte_ipv4_hdr, version_ihl), sizeof(*p8), + &dof); + if (p8 == NULL) + return 0; + + /* check IP version */ + if ((p8[0] & 0xf0) != IPVERSION << 4) + return 0; + + n = (p8[0] & RTE_IPV4_HDR_IHL_MASK) * RTE_IPV4_IHL_MULTIPLIER; + + /* load 3-rd byte of IP data */ + p8 = rte_pktmbuf_read(pkt, n + 3, sizeof(*p8), &dof); + if (p8 == NULL) + return 0; + + v = p8[0]; + + /* load IPv4 src addr */ + p32 = rte_pktmbuf_read(pkt, + offsetof(struct rte_ipv4_hdr, src_addr), sizeof(*p32), + &dof); + if (p32 == NULL) + return 0; + + v += rte_be_to_cpu_32(p32[0]); + + /* load IPv4 total length */ + p16 = rte_pktmbuf_read(pkt, + offsetof(struct rte_ipv4_hdr, total_length), sizeof(*p16), + &dof); + if (p16 == NULL) + return 0; + + n = rte_be_to_cpu_16(p16[0]); + + /* load last 4 bytes of IP data */ + p32 = rte_pktmbuf_read(pkt, n - sizeof(*p32), sizeof(*p32), &dof); + if (p32 == NULL) + return 0; + + v += rte_be_to_cpu_32(p32[0]); + + /* load 2 bytes from the middle of IP data */ + p16 = rte_pktmbuf_read(pkt, n / 2, sizeof(*p16), &dof); + if (p16 == NULL) + return 0; + + v += rte_be_to_cpu_16(p16[0]); + return v; +} + +static int +test_ld_mbuf1_check(uint64_t rc, const void *arg) +{ + const struct dummy_mbuf *dm; + uint64_t v; + + dm = arg; + v = test_ld_mbuf1(dm->mb); + return cmp_res(__func__, v, rc, arg, arg, 0); +} + +/* + * same as ld_mbuf1, but then trancate the mbuf by 1B, + * so load of last 4B fail. + */ +static void +test_ld_mbuf2_prepare(void *arg) +{ + struct dummy_mbuf *dm; + + test_ld_mbuf1_prepare(arg); + dm = arg; + rte_pktmbuf_trim(dm->mb, 1); +} + +static int +test_ld_mbuf2_check(uint64_t rc, const void *arg) +{ + return cmp_res(__func__, 0, rc, arg, arg, 0); +} + +/* same as test_ld_mbuf1, but now store intermediate results on the stack */ +static const struct ebpf_insn test_ld_mbuf3_prog[] = { + + /* BPF_ABS/BPF_IND implicitly expect mbuf ptr in R6 */ + { + .code = (EBPF_ALU64 | EBPF_MOV | BPF_X), + .dst_reg = EBPF_REG_6, + .src_reg = EBPF_REG_1, + }, + /* load IPv4 version and IHL */ + { + .code = (BPF_LD | BPF_ABS | BPF_B), + .imm = offsetof(struct rte_ipv4_hdr, version_ihl), + }, + /* check IP version */ + { + .code = (EBPF_ALU64 | EBPF_MOV | BPF_X), + .dst_reg = EBPF_REG_2, + .src_reg = EBPF_REG_0, + }, + { + .code = (BPF_ALU | BPF_AND | BPF_K), + .dst_reg = EBPF_REG_2, + .imm = 0xf0, + }, + { + .code = (BPF_JMP | BPF_JEQ | BPF_K), + .dst_reg = EBPF_REG_2, + .imm = IPVERSION << 4, + .off = 2, + }, + /* invalid IP version, return 0 */ + { + .code = (EBPF_ALU64 | BPF_XOR | BPF_X), + .dst_reg = EBPF_REG_0, + .src_reg = EBPF_REG_0, + }, + { + .code = (BPF_JMP | EBPF_EXIT), + }, + /* load 3-rd byte of IP data */ + { + .code = (BPF_ALU | BPF_AND | BPF_K), + .dst_reg = EBPF_REG_0, + .imm = RTE_IPV4_HDR_IHL_MASK, + }, + { + .code = (BPF_ALU | BPF_LSH | BPF_K), + .dst_reg = EBPF_REG_0, + .imm = 2, + }, + { + .code = (BPF_LD | BPF_IND | BPF_B), + .src_reg = EBPF_REG_0, + .imm = 3, + }, + { + .code = (BPF_STX | BPF_MEM | BPF_B), + .dst_reg = EBPF_REG_10, + .src_reg = EBPF_REG_0, + .off = (int16_t)(offsetof(struct dummy_offset, u8) - + sizeof(struct dummy_offset)), + }, + /* load IPv4 src addr */ + { + .code = (BPF_LD | BPF_ABS | BPF_W), + .imm = offsetof(struct rte_ipv4_hdr, src_addr), + }, + { + .code = (BPF_STX | BPF_MEM | BPF_W), + .dst_reg = EBPF_REG_10, + .src_reg = EBPF_REG_0, + .off = (int16_t)(offsetof(struct dummy_offset, u32) - + sizeof(struct dummy_offset)), + }, + /* load IPv4 total length */ + { + .code = (BPF_LD | BPF_ABS | BPF_H), + .imm = offsetof(struct rte_ipv4_hdr, total_length), + }, + { + .code = (EBPF_ALU64 | EBPF_MOV | BPF_X), + .dst_reg = EBPF_REG_8, + .src_reg = EBPF_REG_0, + }, + /* load last 4 bytes of IP data */ + { + .code = (BPF_LD | BPF_IND | BPF_W), + .src_reg = EBPF_REG_8, + .imm = -(int32_t)sizeof(uint32_t), + }, + { + .code = (BPF_STX | BPF_MEM | EBPF_DW), + .dst_reg = EBPF_REG_10, + .src_reg = EBPF_REG_0, + .off = (int16_t)(offsetof(struct dummy_offset, u64) - + sizeof(struct dummy_offset)), + }, + /* load 2 bytes from the middle of IP data */ + { + .code = (EBPF_ALU64 | BPF_RSH | BPF_K), + .dst_reg = EBPF_REG_8, + .imm = 1, + }, + { + .code = (BPF_LD | BPF_IND | BPF_H), + .src_reg = EBPF_REG_8, + }, + { + .code = (BPF_LDX | BPF_MEM | EBPF_DW), + .dst_reg = EBPF_REG_1, + .src_reg = EBPF_REG_10, + .off = (int16_t)(offsetof(struct dummy_offset, u64) - + sizeof(struct dummy_offset)), + }, + { + .code = (EBPF_ALU64 | BPF_ADD | BPF_X), + .dst_reg = EBPF_REG_0, + .src_reg = EBPF_REG_1, + }, + { + .code = (BPF_LDX | BPF_MEM | BPF_W), + .dst_reg = EBPF_REG_1, + .src_reg = EBPF_REG_10, + .off = (int16_t)(offsetof(struct dummy_offset, u32) - + sizeof(struct dummy_offset)), + }, + { + .code = (EBPF_ALU64 | BPF_ADD | BPF_X), + .dst_reg = EBPF_REG_0, + .src_reg = EBPF_REG_1, + }, + { + .code = (BPF_LDX | BPF_MEM | BPF_B), + .dst_reg = EBPF_REG_1, + .src_reg = EBPF_REG_10, + .off = (int16_t)(offsetof(struct dummy_offset, u8) - + sizeof(struct dummy_offset)), + }, + { + .code = (EBPF_ALU64 | BPF_ADD | BPF_X), + .dst_reg = EBPF_REG_0, + .src_reg = EBPF_REG_1, + }, + { + .code = (BPF_JMP | EBPF_EXIT), + }, +}; + /* all bpf test cases */ static const struct bpf_test tests[] = { { @@ -2704,6 +3119,54 @@ static const struct bpf_test tests[] = { /* for now don't support function calls on 32 bit platform */ .allow_fail = (sizeof(uint64_t) != sizeof(uintptr_t)), }, + { + .name = "test_ld_mbuf1", + .arg_sz = sizeof(struct dummy_mbuf), + .prm = { + .ins = test_ld_mbuf1_prog, + .nb_ins = RTE_DIM(test_ld_mbuf1_prog), + .prog_arg = { + .type = RTE_BPF_ARG_PTR_MBUF, + .buf_size = sizeof(struct dummy_mbuf), + }, + }, + .prepare = test_ld_mbuf1_prepare, + .check_result = test_ld_mbuf1_check, + /* mbuf as input argument is not supported on 32 bit platform */ + .allow_fail = (sizeof(uint64_t) != sizeof(uintptr_t)), + }, + { + .name = "test_ld_mbuf2", + .arg_sz = sizeof(struct dummy_mbuf), + .prm = { + .ins = test_ld_mbuf1_prog, + .nb_ins = RTE_DIM(test_ld_mbuf1_prog), + .prog_arg = { + .type = RTE_BPF_ARG_PTR_MBUF, + .buf_size = sizeof(struct dummy_mbuf), + }, + }, + .prepare = test_ld_mbuf2_prepare, + .check_result = test_ld_mbuf2_check, + /* mbuf as input argument is not supported on 32 bit platform */ + .allow_fail = (sizeof(uint64_t) != sizeof(uintptr_t)), + }, + { + .name = "test_ld_mbuf3", + .arg_sz = sizeof(struct dummy_mbuf), + .prm = { + .ins = test_ld_mbuf3_prog, + .nb_ins = RTE_DIM(test_ld_mbuf3_prog), + .prog_arg = { + .type = RTE_BPF_ARG_PTR_MBUF, + .buf_size = sizeof(struct dummy_mbuf), + }, + }, + .prepare = test_ld_mbuf1_prepare, + .check_result = test_ld_mbuf1_check, + /* mbuf as input argument is not supported on 32 bit platform */ + .allow_fail = (sizeof(uint64_t) != sizeof(uintptr_t)), + }, }; static int diff --git a/doc/guides/prog_guide/bpf_lib.rst b/doc/guides/prog_guide/bpf_lib.rst index 9c728da7bd..1feb7734a3 100644 --- a/doc/guides/prog_guide/bpf_lib.rst +++ b/doc/guides/prog_guide/bpf_lib.rst @@ -27,6 +27,35 @@ The library API provides the following basic operations: * Load BPF program from the ELF file and install callback to execute it on given ethdev port/queue. +Packet data load instructions +----------------------------- + +DPDK supports two non-generic instructions: ``(BPF_ABS | size | BPF_LD)`` +and ``(BPF_IND | size | BPF_LD)`` which are used to access packet data. +These instructions can only be used when execution context is a pointer to +``struct rte_mbuf`` and have seven implicit operands. +Register ``R6`` is an implicit input that must contain pointer to ``rte_mbuf``. +Register ``R0`` is an implicit output which contains the data fetched from the +packet. Registers ``R1-R5`` are scratch registers +and must not be used to store the data across these instructions. +These instructions have implicit program exit condition as well. When +eBPF program is trying to access the data beyond the packet boundary, +the interpreter will abort the execution of the program. JIT compilers +therefore must preserve this property. ``src_reg`` and ``imm32`` fields are +explicit inputs to these instructions. +For example, ``(BPF_IND | BPF_W | BPF_LD)`` means: + +.. code-block:: c + + uint32_t tmp; + R0 = rte_pktmbuf_read((const struct rte_mbuf *)R6, src_reg + imm32, + sizeof(tmp), &tmp); + if (R0 == NULL) return FAILED; + R0 = ntohl(*(uint32_t *)R0); + +and ``R1-R5`` were scratched. + + Not currently supported eBPF features ------------------------------------- @@ -34,5 +63,4 @@ Not currently supported eBPF features - cBPF - tail-pointer call - eBPF MAP - - skb - external function calls for 32-bit platforms diff --git a/doc/guides/rel_notes/release_20_08.rst b/doc/guides/rel_notes/release_20_08.rst index f5a22bc4b9..7629b1fb38 100644 --- a/doc/guides/rel_notes/release_20_08.rst +++ b/doc/guides/rel_notes/release_20_08.rst @@ -68,6 +68,13 @@ New Features * Added new PMD devarg ``reclaim_mem_mode``. +* **Added support for BPF_ABS/BPF_IND load instructions.** + + Added support for two BPF non-generic instructions: + ``(BPF_ABS | | BPF_LD)`` and ``(BPF_IND | | BPF_LD)`` + which are used to access packet data in a safe manner. Currently JIT support + for these instructions is implemented for x86 only. + Removed Items ------------- diff --git a/lib/librte_bpf/bpf_exec.c b/lib/librte_bpf/bpf_exec.c index 1bb2266436..b921112feb 100644 --- a/lib/librte_bpf/bpf_exec.c +++ b/lib/librte_bpf/bpf_exec.c @@ -74,6 +74,26 @@ (uintptr_t)((reg)[(ins)->dst_reg] + (ins)->off), \ reg[ins->src_reg])) +/* BPF_LD | BPF_ABS/BPF_IND */ + +#define NOP(x) (x) + +#define BPF_LD_ABS(bpf, reg, ins, type, op) do { \ + const type *p = bpf_ld_mbuf(bpf, reg, ins, (ins)->imm, sizeof(type)); \ + if (p == NULL) \ + return 0; \ + reg[EBPF_REG_0] = op(p[0]); \ +} while (0) + +#define BPF_LD_IND(bpf, reg, ins, type, op) do { \ + uint32_t ofs = reg[ins->src_reg] + (ins)->imm; \ + const type *p = bpf_ld_mbuf(bpf, reg, ins, ofs, sizeof(type)); \ + if (p == NULL) \ + return 0; \ + reg[EBPF_REG_0] = op(p[0]); \ +} while (0) + + static inline void bpf_alu_be(uint64_t reg[EBPF_REG_NUM], const struct ebpf_insn *ins) { @@ -112,6 +132,23 @@ bpf_alu_le(uint64_t reg[EBPF_REG_NUM], const struct ebpf_insn *ins) } } +static inline const void * +bpf_ld_mbuf(const struct rte_bpf *bpf, uint64_t reg[EBPF_REG_NUM], + const struct ebpf_insn *ins, uint32_t off, uint32_t len) +{ + const struct rte_mbuf *mb; + const void *p; + + mb = (const struct rte_mbuf *)(uintptr_t)reg[EBPF_REG_6]; + p = rte_pktmbuf_read(mb, off, len, reg + EBPF_REG_0); + if (p == NULL) + RTE_BPF_LOG(DEBUG, "%s(bpf=%p, mbuf=%p, ofs=%u, len=%u): " + "load beyond packet boundary at pc: %#zx;\n", + __func__, bpf, mb, off, len, + (uintptr_t)(ins) - (uintptr_t)(bpf)->prm.ins); + return p; +} + static inline uint64_t bpf_exec(const struct rte_bpf *bpf, uint64_t reg[EBPF_REG_NUM]) { @@ -296,6 +333,26 @@ bpf_exec(const struct rte_bpf *bpf, uint64_t reg[EBPF_REG_NUM]) (uint64_t)(uint32_t)ins[1].imm << 32; ins++; break; + /* load absolute instructions */ + case (BPF_LD | BPF_ABS | BPF_B): + BPF_LD_ABS(bpf, reg, ins, uint8_t, NOP); + break; + case (BPF_LD | BPF_ABS | BPF_H): + BPF_LD_ABS(bpf, reg, ins, uint16_t, rte_be_to_cpu_16); + break; + case (BPF_LD | BPF_ABS | BPF_W): + BPF_LD_ABS(bpf, reg, ins, uint32_t, rte_be_to_cpu_32); + break; + /* load indirect instructions */ + case (BPF_LD | BPF_IND | BPF_B): + BPF_LD_IND(bpf, reg, ins, uint8_t, NOP); + break; + case (BPF_LD | BPF_IND | BPF_H): + BPF_LD_IND(bpf, reg, ins, uint16_t, rte_be_to_cpu_16); + break; + case (BPF_LD | BPF_IND | BPF_W): + BPF_LD_IND(bpf, reg, ins, uint32_t, rte_be_to_cpu_32); + break; /* store instructions */ case (BPF_STX | BPF_MEM | BPF_B): BPF_ST_REG(reg, ins, uint8_t); diff --git a/lib/librte_bpf/bpf_validate.c b/lib/librte_bpf/bpf_validate.c index 80d21fabbe..fecdda0e1b 100644 --- a/lib/librte_bpf/bpf_validate.c +++ b/lib/librte_bpf/bpf_validate.c @@ -102,6 +102,9 @@ struct bpf_ins_check { #define WRT_REGS RTE_LEN2MASK(EBPF_REG_10, uint16_t) #define ZERO_REG RTE_LEN2MASK(EBPF_REG_1, uint16_t) +/* For LD_IND R6 is an implicit CTX register. */ +#define IND_SRC_REGS (WRT_REGS ^ 1 << EBPF_REG_6) + /* * check and evaluate functions for particular instruction types. */ @@ -580,6 +583,42 @@ eval_neg(struct bpf_reg_val *rd, size_t opsz, uint64_t msk) rd->s.min = RTE_MIN(sx, sy); } +static const char * +eval_ld_mbuf(struct bpf_verifier *bvf, const struct ebpf_insn *ins) +{ + uint32_t i, mode; + struct bpf_reg_val *rv, ri, rs; + + mode = BPF_MODE(ins->code); + + /* R6 is an implicit input that must contain pointer to mbuf */ + if (bvf->evst->rv[EBPF_REG_6].v.type != RTE_BPF_ARG_PTR_MBUF) + return "invalid type for implicit ctx register"; + + if (mode == BPF_IND) { + rs = bvf->evst->rv[ins->src_reg]; + if (rs.v.type != RTE_BPF_ARG_RAW) + return "unexpected type for src register"; + + eval_fill_imm(&ri, UINT64_MAX, ins->imm); + eval_add(&rs, &ri, UINT64_MAX); + + if (rs.s.max < 0 || rs.u.min > UINT32_MAX) + return "mbuf boundary violation"; + } + + /* R1-R5 scratch registers */ + for (i = EBPF_REG_1; i != EBPF_REG_6; i++) + bvf->evst->rv[i].v.type = RTE_BPF_ARG_UNDEF; + + /* R0 is an implicit output, contains data fetched from the packet */ + rv = bvf->evst->rv + EBPF_REG_0; + rv->v.size = bpf_size(BPF_SIZE(ins->code)); + eval_fill_max_bound(rv, RTE_LEN2MASK(rv->v.size * CHAR_BIT, uint64_t)); + + return NULL; +} + /* * check that destination and source operand are in defined state. */ @@ -1425,6 +1464,44 @@ static const struct bpf_ins_check ins_chk[UINT8_MAX + 1] = { .imm = { .min = 0, .max = UINT32_MAX}, .eval = eval_ld_imm64, }, + /* load absolute instructions */ + [(BPF_LD | BPF_ABS | BPF_B)] = { + .mask = {. dreg = ZERO_REG, .sreg = ZERO_REG}, + .off = { .min = 0, .max = 0}, + .imm = { .min = 0, .max = INT32_MAX}, + .eval = eval_ld_mbuf, + }, + [(BPF_LD | BPF_ABS | BPF_H)] = { + .mask = {. dreg = ZERO_REG, .sreg = ZERO_REG}, + .off = { .min = 0, .max = 0}, + .imm = { .min = 0, .max = INT32_MAX}, + .eval = eval_ld_mbuf, + }, + [(BPF_LD | BPF_ABS | BPF_W)] = { + .mask = {. dreg = ZERO_REG, .sreg = ZERO_REG}, + .off = { .min = 0, .max = 0}, + .imm = { .min = 0, .max = INT32_MAX}, + .eval = eval_ld_mbuf, + }, + /* load indirect instructions */ + [(BPF_LD | BPF_IND | BPF_B)] = { + .mask = {. dreg = ZERO_REG, .sreg = IND_SRC_REGS}, + .off = { .min = 0, .max = 0}, + .imm = { .min = 0, .max = UINT32_MAX}, + .eval = eval_ld_mbuf, + }, + [(BPF_LD | BPF_IND | BPF_H)] = { + .mask = {. dreg = ZERO_REG, .sreg = IND_SRC_REGS}, + .off = { .min = 0, .max = 0}, + .imm = { .min = 0, .max = UINT32_MAX}, + .eval = eval_ld_mbuf, + }, + [(BPF_LD | BPF_IND | BPF_W)] = { + .mask = {. dreg = ZERO_REG, .sreg = IND_SRC_REGS}, + .off = { .min = 0, .max = 0}, + .imm = { .min = 0, .max = UINT32_MAX}, + .eval = eval_ld_mbuf, + }, /* store REG instructions */ [(BPF_STX | BPF_MEM | BPF_B)] = { .mask = { .dreg = ALL_REGS, .sreg = ALL_REGS}, -- 2.20.1