From a6ed38361b1e0f08d630bd491051c254d1fc71b9 Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Thu, 30 Jul 2015 16:04:22 +0200 Subject: bpf_jit_disasm: also support reading jit dump from file This patch adds support to read the dmesg BPF JIT dump also from a file instead of the klog buffer. I found this quite useful when going through some 'before/after patch' logs. It also fixes a regex leak found by valgrind when no image dump was found. Signed-off-by: Daniel Borkmann Signed-off-by: David S. Miller --- tools/net/bpf_jit_disasm.c | 109 +++++++++++++++++++++++++++++++++++++-------- 1 file changed, 90 insertions(+), 19 deletions(-) (limited to 'tools') diff --git a/tools/net/bpf_jit_disasm.c b/tools/net/bpf_jit_disasm.c index 618c2bcd4eab..2cd3d4c99738 100644 --- a/tools/net/bpf_jit_disasm.c +++ b/tools/net/bpf_jit_disasm.c @@ -22,9 +22,14 @@ #include #include #include +#include +#include #include #include -#include +#include + +#define CMD_ACTION_SIZE_BUFFER 10 +#define CMD_ACTION_READ_ALL 3 static void get_exec_path(char *tpath, size_t size) { @@ -87,20 +92,66 @@ static void get_asm_insns(uint8_t *image, size_t len, int opcodes) bfd_close(bfdf); } -static char *get_klog_buff(int *klen) +static char *get_klog_buff(unsigned int *klen) { - int ret, len = klogctl(10, NULL, 0); - char *buff = malloc(len); + int ret, len; + char *buff; + + len = klogctl(CMD_ACTION_SIZE_BUFFER, NULL, 0); + buff = malloc(len); + if (!buff) + return NULL; + + ret = klogctl(CMD_ACTION_READ_ALL, buff, len); + if (ret < 0) { + free(buff); + return NULL; + } - assert(buff && klen); - ret = klogctl(3, buff, len); - assert(ret >= 0); *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_klog_buff(char *buff) +static void put_log_buff(char *buff) { free(buff); } @@ -138,8 +189,10 @@ static int get_last_jit_image(char *haystack, size_t hlen, ptr = haystack + off - (pmatch[0].rm_eo - pmatch[0].rm_so); ret = sscanf(ptr, "flen=%d proglen=%d pass=%d image=%lx", &flen, &proglen, &pass, &base); - if (ret != 4) + if (ret != 4) { + regfree(®ex); return 0; + } tmp = ptr = haystack + off; while ((ptr = strtok(tmp, "\n")) != NULL && ulen < ilen) { @@ -169,31 +222,49 @@ static int get_last_jit_image(char *haystack, size_t hlen, return ulen; } +static void usage(void) +{ + printf("Usage: bpf_jit_disasm [...]\n"); + printf(" -o Also display related opcodes (default: off).\n"); + printf(" -f Read last image dump from file or stdin (default: klog).\n"); + printf(" -h Display this help.\n"); +} + int main(int argc, char **argv) { - int len, klen, opcodes = 0; - char *kbuff; + unsigned int len, klen, opt, opcodes = 0; static uint8_t image[32768]; + char *kbuff, *file = NULL; - if (argc > 1) { - if (!strncmp("-o", argv[argc - 1], 2)) { + while ((opt = getopt(argc, argv, "of:")) != -1) { + switch (opt) { + case 'o': opcodes = 1; - } else { - printf("usage: bpf_jit_disasm [-o: show opcodes]\n"); - exit(0); + break; + case 'f': + file = optarg; + break; + default: + usage(); + return -1; } } bfd_init(); memset(image, 0, sizeof(image)); - kbuff = get_klog_buff(&klen); + kbuff = get_log_buff(file, &klen); + if (!kbuff) { + fprintf(stderr, "Could not retrieve log buffer!\n"); + return -1; + } len = get_last_jit_image(kbuff, klen, image, sizeof(image)); if (len > 0) get_asm_insns(image, len, opcodes); + else + fprintf(stderr, "No JIT image found!\n"); - put_klog_buff(kbuff); - + put_log_buff(kbuff); return 0; } -- cgit v1.2.3-58-ga151 From 95e22792fa5460e579a69171777ff79d8725be29 Mon Sep 17 00:00:00 2001 From: Willem de Bruijn Date: Fri, 14 Aug 2015 22:31:36 -0400 Subject: selftests/net: test classic bpf fanout mode Test PACKET_FANOUT_CBPF by inserting a cBPF program that selects a socket by payload. Requires modifying the test program to send packets with multiple payloads. Also fix a bug in testing the return value of mmap() Signed-off-by: Willem de Bruijn Signed-off-by: David S. Miller --- tools/testing/selftests/net/psock_fanout.c | 16 ++++++++++++---- tools/testing/selftests/net/psock_lib.h | 29 +++++++++++++++++++++-------- 2 files changed, 33 insertions(+), 12 deletions(-) (limited to 'tools') diff --git a/tools/testing/selftests/net/psock_fanout.c b/tools/testing/selftests/net/psock_fanout.c index 08c2a36ef7a9..baf46a20e1b3 100644 --- a/tools/testing/selftests/net/psock_fanout.c +++ b/tools/testing/selftests/net/psock_fanout.c @@ -19,6 +19,7 @@ * - PACKET_FANOUT_LB * - PACKET_FANOUT_CPU * - PACKET_FANOUT_ROLLOVER + * - PACKET_FANOUT_CBPF * * Todo: * - functionality: PACKET_FANOUT_FLAG_DEFRAG @@ -115,8 +116,8 @@ static char *sock_fanout_open_ring(int fd) ring = mmap(0, req.tp_block_size * req.tp_block_nr, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0); - if (!ring) { - fprintf(stderr, "packetsock ring mmap\n"); + if (ring == MAP_FAILED) { + perror("packetsock ring mmap"); exit(1); } @@ -209,6 +210,7 @@ static int test_datapath(uint16_t typeflags, int port_off, { const int expect0[] = { 0, 0 }; char *rings[2]; + uint8_t type = typeflags & 0xFF; int fds[2], fds_udp[2][2], ret; fprintf(stderr, "test: datapath 0x%hx\n", typeflags); @@ -219,6 +221,9 @@ static int test_datapath(uint16_t typeflags, int port_off, fprintf(stderr, "ERROR: failed open\n"); exit(1); } + if (type == PACKET_FANOUT_CBPF) + sock_setfilter(fds[0], SOL_PACKET, PACKET_FANOUT_DATA); + rings[0] = sock_fanout_open_ring(fds[0]); rings[1] = sock_fanout_open_ring(fds[1]); pair_udp_open(fds_udp[0], PORT_BASE); @@ -227,11 +232,11 @@ static int test_datapath(uint16_t typeflags, int port_off, /* Send data, but not enough to overflow a queue */ pair_udp_send(fds_udp[0], 15); - pair_udp_send(fds_udp[1], 5); + pair_udp_send_char(fds_udp[1], 5, DATA_CHAR_1); ret = sock_fanout_read(fds, rings, expect1); /* Send more data, overflow the queue */ - pair_udp_send(fds_udp[0], 15); + pair_udp_send_char(fds_udp[0], 15, DATA_CHAR_1); /* TODO: ensure consistent order between expect1 and expect2 */ ret |= sock_fanout_read(fds, rings, expect2); @@ -275,6 +280,7 @@ int main(int argc, char **argv) const int expect_rb[2][2] = { { 15, 5 }, { 20, 15 } }; const int expect_cpu0[2][2] = { { 20, 0 }, { 20, 0 } }; const int expect_cpu1[2][2] = { { 0, 20 }, { 0, 20 } }; + const int expect_bpf[2][2] = { { 15, 5 }, { 15, 20 } }; int port_off = 2, tries = 5, ret; test_control_single(); @@ -295,6 +301,8 @@ int main(int argc, char **argv) port_off, expect_lb[0], expect_lb[1]); ret |= test_datapath(PACKET_FANOUT_ROLLOVER, port_off, expect_rb[0], expect_rb[1]); + ret |= test_datapath(PACKET_FANOUT_CBPF, + port_off, expect_bpf[0], expect_bpf[1]); set_cpuaffinity(0); ret |= test_datapath(PACKET_FANOUT_CPU, port_off, diff --git a/tools/testing/selftests/net/psock_lib.h b/tools/testing/selftests/net/psock_lib.h index 37da54ac85a9..24bc7ec1be7d 100644 --- a/tools/testing/selftests/net/psock_lib.h +++ b/tools/testing/selftests/net/psock_lib.h @@ -30,6 +30,7 @@ #define DATA_LEN 100 #define DATA_CHAR 'a' +#define DATA_CHAR_1 'b' #define PORT_BASE 8000 @@ -37,29 +38,36 @@ # define __maybe_unused __attribute__ ((__unused__)) #endif -static __maybe_unused void pair_udp_setfilter(int fd) +static __maybe_unused void sock_setfilter(int fd, int lvl, int optnum) { struct sock_filter bpf_filter[] = { { 0x80, 0, 0, 0x00000000 }, /* LD pktlen */ - { 0x35, 0, 5, DATA_LEN }, /* JGE DATA_LEN [f goto nomatch]*/ + { 0x35, 0, 4, DATA_LEN }, /* JGE DATA_LEN [f goto nomatch]*/ { 0x30, 0, 0, 0x00000050 }, /* LD ip[80] */ - { 0x15, 0, 3, DATA_CHAR }, /* JEQ DATA_CHAR [f goto nomatch]*/ - { 0x30, 0, 0, 0x00000051 }, /* LD ip[81] */ - { 0x15, 0, 1, DATA_CHAR }, /* JEQ DATA_CHAR [f goto nomatch]*/ + { 0x15, 1, 0, DATA_CHAR }, /* JEQ DATA_CHAR [t goto match]*/ + { 0x15, 0, 1, DATA_CHAR_1}, /* JEQ DATA_CHAR_1 [t goto match]*/ { 0x06, 0, 0, 0x00000060 }, /* RET match */ { 0x06, 0, 0, 0x00000000 }, /* RET no match */ }; struct sock_fprog bpf_prog; + if (lvl == SOL_PACKET && optnum == PACKET_FANOUT_DATA) + bpf_filter[5].code = 0x16; /* RET A */ + bpf_prog.filter = bpf_filter; bpf_prog.len = sizeof(bpf_filter) / sizeof(struct sock_filter); - if (setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, &bpf_prog, + if (setsockopt(fd, lvl, optnum, &bpf_prog, sizeof(bpf_prog))) { perror("setsockopt SO_ATTACH_FILTER"); exit(1); } } +static __maybe_unused void pair_udp_setfilter(int fd) +{ + sock_setfilter(fd, SOL_SOCKET, SO_ATTACH_FILTER); +} + static __maybe_unused void pair_udp_open(int fds[], uint16_t port) { struct sockaddr_in saddr, daddr; @@ -96,11 +104,11 @@ static __maybe_unused void pair_udp_open(int fds[], uint16_t port) } } -static __maybe_unused void pair_udp_send(int fds[], int num) +static __maybe_unused void pair_udp_send_char(int fds[], int num, char payload) { char buf[DATA_LEN], rbuf[DATA_LEN]; - memset(buf, DATA_CHAR, sizeof(buf)); + memset(buf, payload, sizeof(buf)); while (num--) { /* Should really handle EINTR and EAGAIN */ if (write(fds[0], buf, sizeof(buf)) != sizeof(buf)) { @@ -118,6 +126,11 @@ static __maybe_unused void pair_udp_send(int fds[], int num) } } +static __maybe_unused void pair_udp_send(int fds[], int num) +{ + return pair_udp_send_char(fds, num, DATA_CHAR); +} + static __maybe_unused void pair_udp_close(int fds[]) { close(fds[0]); -- cgit v1.2.3-58-ga151 From 30da679e679dbe7bb103c5d9c137ec5a070b7150 Mon Sep 17 00:00:00 2001 From: Willem de Bruijn Date: Fri, 14 Aug 2015 22:31:37 -0400 Subject: selftests/net: test extended BPF fanout mode Test PACKET_FANOUT_EBPF by inserting a program into the the kernel with bpf(), then attaching it to the fanout group. Observe the same payload-based distribution as in the PACKET_FANOUT_CBPF test. Signed-off-by: Willem de Bruijn Signed-off-by: David S. Miller --- tools/testing/selftests/net/psock_fanout.c | 53 ++++++++++++++++++++++++++++++ 1 file changed, 53 insertions(+) (limited to 'tools') diff --git a/tools/testing/selftests/net/psock_fanout.c b/tools/testing/selftests/net/psock_fanout.c index baf46a20e1b3..412459369686 100644 --- a/tools/testing/selftests/net/psock_fanout.c +++ b/tools/testing/selftests/net/psock_fanout.c @@ -20,6 +20,7 @@ * - PACKET_FANOUT_CPU * - PACKET_FANOUT_ROLLOVER * - PACKET_FANOUT_CBPF + * - PACKET_FANOUT_EBPF * * Todo: * - functionality: PACKET_FANOUT_FLAG_DEFRAG @@ -45,7 +46,9 @@ #include #include #include +#include /* for __NR_bpf */ #include +#include #include #include #include @@ -92,6 +95,51 @@ static int sock_fanout_open(uint16_t typeflags, int num_packets) return fd; } +static void sock_fanout_set_ebpf(int fd) +{ + const int len_off = __builtin_offsetof(struct __sk_buff, len); + struct bpf_insn prog[] = { + { BPF_ALU64 | BPF_MOV | BPF_X, 6, 1, 0, 0 }, + { BPF_LDX | BPF_W | BPF_MEM, 0, 6, len_off, 0 }, + { BPF_JMP | BPF_JGE | BPF_K, 0, 0, 1, DATA_LEN }, + { BPF_JMP | BPF_JA | BPF_K, 0, 0, 4, 0 }, + { BPF_LD | BPF_B | BPF_ABS, 0, 0, 0, 0x50 }, + { BPF_JMP | BPF_JEQ | BPF_K, 0, 0, 2, DATA_CHAR }, + { BPF_JMP | BPF_JEQ | BPF_K, 0, 0, 1, DATA_CHAR_1 }, + { BPF_ALU | BPF_MOV | BPF_K, 0, 0, 0, 0 }, + { BPF_JMP | BPF_EXIT, 0, 0, 0, 0 } + }; + char log_buf[512]; + union bpf_attr attr; + int pfd; + + memset(&attr, 0, sizeof(attr)); + attr.prog_type = BPF_PROG_TYPE_SOCKET_FILTER; + attr.insns = (unsigned long) prog; + attr.insn_cnt = sizeof(prog) / sizeof(prog[0]); + attr.license = (unsigned long) "GPL"; + attr.log_buf = (unsigned long) log_buf, + attr.log_size = sizeof(log_buf), + attr.log_level = 1, + + pfd = syscall(__NR_bpf, BPF_PROG_LOAD, &attr, sizeof(attr)); + if (pfd < 0) { + perror("bpf"); + fprintf(stderr, "bpf verifier:\n%s\n", log_buf); + exit(1); + } + + if (setsockopt(fd, SOL_PACKET, PACKET_FANOUT_DATA, &pfd, sizeof(pfd))) { + perror("fanout data ebpf"); + exit(1); + } + + if (close(pfd)) { + perror("close ebpf"); + exit(1); + } +} + static char *sock_fanout_open_ring(int fd) { struct tpacket_req req = { @@ -223,6 +271,8 @@ static int test_datapath(uint16_t typeflags, int port_off, } if (type == PACKET_FANOUT_CBPF) sock_setfilter(fds[0], SOL_PACKET, PACKET_FANOUT_DATA); + else if (type == PACKET_FANOUT_EBPF) + sock_fanout_set_ebpf(fds[0]); rings[0] = sock_fanout_open_ring(fds[0]); rings[1] = sock_fanout_open_ring(fds[1]); @@ -301,8 +351,11 @@ int main(int argc, char **argv) port_off, expect_lb[0], expect_lb[1]); ret |= test_datapath(PACKET_FANOUT_ROLLOVER, port_off, expect_rb[0], expect_rb[1]); + ret |= test_datapath(PACKET_FANOUT_CBPF, port_off, expect_bpf[0], expect_bpf[1]); + ret |= test_datapath(PACKET_FANOUT_EBPF, + port_off, expect_bpf[0], expect_bpf[1]); set_cpuaffinity(0); ret |= test_datapath(PACKET_FANOUT_CPU, port_off, -- cgit v1.2.3-58-ga151