| #!/usr/bin/python |
| # @lint-avoid-python-3-compatibility-imports |
| # |
| # tcplife Trace the lifespan of TCP sessions and summarize. |
| # For Linux, uses BCC, BPF. Embedded C. |
| # |
| # USAGE: tcplife [-h] [-C] [-S] [-p PID] [interval [count]] |
| # |
| # This uses dynamic tracing of kernel functions, and will need to be updated |
| # to match kernel changes. |
| # |
| # While throughput counters are emitted, they are fetched in a low-overhead |
| # manner: reading members of the tcp_info struct on TCP close. ie, we do not |
| # trace send/receive. |
| # |
| # Copyright 2016 Netflix, Inc. |
| # Licensed under the Apache License, Version 2.0 (the "License") |
| # |
| # IDEA: Julia Evans |
| # |
| # 18-Oct-2016 Brendan Gregg Created this. |
| |
| from __future__ import print_function |
| from bcc import BPF |
| import argparse |
| from socket import inet_ntop, ntohs, AF_INET, AF_INET6 |
| from struct import pack |
| import ctypes as ct |
| from time import strftime |
| |
| # arguments |
| examples = """examples: |
| ./tcplife # trace all TCP connect()s |
| ./tcplife -t # include time column (HH:MM:SS) |
| ./tcplife -w # wider colums (fit IPv6) |
| ./tcplife -stT # csv output, with times & timestamps |
| ./tcplife -p 181 # only trace PID 181 |
| ./tcplife -L 80 # only trace local port 80 |
| ./tcplife -L 80,81 # only trace local ports 80 and 81 |
| ./tcplife -D 80 # only trace remote port 80 |
| """ |
| parser = argparse.ArgumentParser( |
| description="Trace the lifespan of TCP sessions and summarize", |
| formatter_class=argparse.RawDescriptionHelpFormatter, |
| epilog=examples) |
| parser.add_argument("-T", "--time", action="store_true", |
| help="include time column on output (HH:MM:SS)") |
| parser.add_argument("-t", "--timestamp", action="store_true", |
| help="include timestamp on output (seconds)") |
| parser.add_argument("-w", "--wide", action="store_true", |
| help="wide column output (fits IPv6 addresses)") |
| parser.add_argument("-s", "--csv", action="store_true", |
| help="comma seperated values output") |
| parser.add_argument("-p", "--pid", |
| help="trace this PID only") |
| parser.add_argument("-L", "--localport", |
| help="comma-separated list of local ports to trace.") |
| parser.add_argument("-D", "--remoteport", |
| help="comma-separated list of remote ports to trace.") |
| args = parser.parse_args() |
| debug = 0 |
| |
| # define BPF program |
| bpf_text = """ |
| #include <uapi/linux/ptrace.h> |
| #define KBUILD_MODNAME "foo" |
| #include <linux/tcp.h> |
| #include <net/sock.h> |
| #include <bcc/proto.h> |
| |
| BPF_HASH(birth, struct sock *, u64); |
| |
| // separate data structs for ipv4 and ipv6 |
| struct ipv4_data_t { |
| // XXX: switch some to u32's when supported |
| u64 ts_us; |
| u64 pid; |
| u64 saddr; |
| u64 daddr; |
| u64 ports; |
| u64 rx_b; |
| u64 tx_b; |
| u64 span_us; |
| char task[TASK_COMM_LEN]; |
| }; |
| BPF_PERF_OUTPUT(ipv4_events); |
| |
| struct ipv6_data_t { |
| u64 ts_us; |
| u64 pid; |
| unsigned __int128 saddr; |
| unsigned __int128 daddr; |
| u64 ports; |
| u64 rx_b; |
| u64 tx_b; |
| u64 span_us; |
| char task[TASK_COMM_LEN]; |
| }; |
| BPF_PERF_OUTPUT(ipv6_events); |
| |
| struct id_t { |
| u32 pid; |
| char task[TASK_COMM_LEN]; |
| }; |
| BPF_HASH(whoami, struct sock *, struct id_t); |
| |
| int kprobe__tcp_set_state(struct pt_regs *ctx, struct sock *sk, int state) |
| { |
| u32 pid = bpf_get_current_pid_tgid() >> 32; |
| |
| // lport is either used in a filter here, or later |
| u16 lport = sk->__sk_common.skc_num; |
| FILTER_LPORT |
| |
| // dport is either used in a filter here, or later |
| u16 dport = sk->__sk_common.skc_dport; |
| FILTER_DPORT |
| |
| /* |
| * This tool includes PID and comm context. It's best effort, and may |
| * be wrong in some situations. It currently works like this: |
| * - record timestamp on any state < TCP_FIN_WAIT1 |
| * - cache task context on: |
| * TCP_SYN_SENT: tracing from client |
| * TCP_LAST_ACK: client-closed from server |
| * - do output on TCP_CLOSE: |
| * fetch task context if cached, or use current task |
| */ |
| |
| // capture birth time |
| if (state < TCP_FIN_WAIT1) { |
| /* |
| * Matching just ESTABLISHED may be sufficient, provided no code-path |
| * sets ESTABLISHED without a tcp_set_state() call. Until we know |
| * that for sure, match all early states to increase chances a |
| * timestamp is set. |
| * Note that this needs to be set before the PID filter later on, |
| * since the PID isn't reliable for these early stages, so we must |
| * save all timestamps and do the PID filter later when we can. |
| */ |
| u64 ts = bpf_ktime_get_ns(); |
| birth.update(&sk, &ts); |
| } |
| |
| // record PID & comm on SYN_SENT |
| if (state == TCP_SYN_SENT || state == TCP_LAST_ACK) { |
| // now we can PID filter, both here and a little later on for CLOSE |
| FILTER_PID |
| struct id_t me = {.pid = pid}; |
| bpf_get_current_comm(&me.task, sizeof(me.task)); |
| whoami.update(&sk, &me); |
| } |
| |
| if (state != TCP_CLOSE) |
| return 0; |
| |
| // calculate lifespan |
| u64 *tsp, delta_us; |
| tsp = birth.lookup(&sk); |
| if (tsp == 0) { |
| whoami.delete(&sk); // may not exist |
| return 0; // missed create |
| } |
| delta_us = (bpf_ktime_get_ns() - *tsp) / 1000; |
| birth.delete(&sk); |
| |
| // fetch possible cached data, and filter |
| struct id_t *mep; |
| mep = whoami.lookup(&sk); |
| if (mep != 0) |
| pid = mep->pid; |
| FILTER_PID |
| |
| // get throughput stats. see tcp_get_info(). |
| u64 rx_b = 0, tx_b = 0, sport = 0; |
| struct tcp_sock *tp = (struct tcp_sock *)sk; |
| rx_b = tp->bytes_received; |
| tx_b = tp->bytes_acked; |
| |
| u16 family = sk->__sk_common.skc_family; |
| |
| if (family == AF_INET) { |
| struct ipv4_data_t data4 = {.span_us = delta_us, |
| .rx_b = rx_b, .tx_b = tx_b}; |
| data4.ts_us = bpf_ktime_get_ns() / 1000; |
| data4.saddr = sk->__sk_common.skc_rcv_saddr; |
| data4.daddr = sk->__sk_common.skc_daddr; |
| // a workaround until data4 compiles with separate lport/dport |
| data4.pid = pid; |
| data4.ports = ntohs(dport) + ((0ULL + lport) << 32); |
| if (mep == 0) { |
| bpf_get_current_comm(&data4.task, sizeof(data4.task)); |
| } else { |
| bpf_probe_read(&data4.task, sizeof(data4.task), (void *)mep->task); |
| } |
| ipv4_events.perf_submit(ctx, &data4, sizeof(data4)); |
| |
| } else /* 6 */ { |
| struct ipv6_data_t data6 = {.span_us = delta_us, |
| .rx_b = rx_b, .tx_b = tx_b}; |
| data6.ts_us = bpf_ktime_get_ns() / 1000; |
| bpf_probe_read(&data6.saddr, sizeof(data6.saddr), |
| sk->__sk_common.skc_v6_rcv_saddr.in6_u.u6_addr32); |
| bpf_probe_read(&data6.daddr, sizeof(data6.daddr), |
| sk->__sk_common.skc_v6_daddr.in6_u.u6_addr32); |
| // a workaround until data6 compiles with separate lport/dport |
| data6.ports = ntohs(dport) + ((0ULL + lport) << 32); |
| data6.pid = pid; |
| if (mep == 0) { |
| bpf_get_current_comm(&data6.task, sizeof(data6.task)); |
| } else { |
| bpf_probe_read(&data6.task, sizeof(data6.task), (void *)mep->task); |
| } |
| ipv6_events.perf_submit(ctx, &data6, sizeof(data6)); |
| } |
| |
| if (mep != 0) |
| whoami.delete(&sk); |
| |
| return 0; |
| } |
| """ |
| |
| # code substitutions |
| if args.pid: |
| bpf_text = bpf_text.replace('FILTER_PID', |
| 'if (pid != %s) { return 0; }' % args.pid) |
| if args.remoteport: |
| dports = [int(dport) for dport in args.remoteport.split(',')] |
| dports_if = ' && '.join(['dport != %d' % ntohs(dport) for dport in dports]) |
| bpf_text = bpf_text.replace('FILTER_DPORT', |
| 'if (%s) { birth.delete(&sk); return 0; }' % dports_if) |
| if args.localport: |
| lports = [int(lport) for lport in args.localport.split(',')] |
| lports_if = ' && '.join(['lport != %d' % lport for lport in lports]) |
| bpf_text = bpf_text.replace('FILTER_LPORT', |
| 'if (%s) { birth.delete(&sk); return 0; }' % lports_if) |
| bpf_text = bpf_text.replace('FILTER_PID', '') |
| bpf_text = bpf_text.replace('FILTER_DPORT', '') |
| bpf_text = bpf_text.replace('FILTER_LPORT', '') |
| |
| if debug: |
| print(bpf_text) |
| |
| # event data |
| TASK_COMM_LEN = 16 # linux/sched.h |
| |
| class Data_ipv4(ct.Structure): |
| _fields_ = [ |
| ("ts_us", ct.c_ulonglong), |
| ("pid", ct.c_ulonglong), |
| ("saddr", ct.c_ulonglong), |
| ("daddr", ct.c_ulonglong), |
| ("ports", ct.c_ulonglong), |
| ("rx_b", ct.c_ulonglong), |
| ("tx_b", ct.c_ulonglong), |
| ("span_us", ct.c_ulonglong), |
| ("task", ct.c_char * TASK_COMM_LEN) |
| ] |
| |
| class Data_ipv6(ct.Structure): |
| _fields_ = [ |
| ("ts_us", ct.c_ulonglong), |
| ("pid", ct.c_ulonglong), |
| ("saddr", (ct.c_ulonglong * 2)), |
| ("daddr", (ct.c_ulonglong * 2)), |
| ("ports", ct.c_ulonglong), |
| ("rx_b", ct.c_ulonglong), |
| ("tx_b", ct.c_ulonglong), |
| ("span_us", ct.c_ulonglong), |
| ("task", ct.c_char * TASK_COMM_LEN) |
| ] |
| |
| # |
| # Setup output formats |
| # |
| # Don't change the default output (next 2 lines): this fits in 80 chars. I |
| # know it doesn't have NS or UIDs etc. I know. If you really, really, really |
| # need to add columns, columns that solve real actual problems, I'd start by |
| # adding an extended mode (-x) to included those columns. |
| # |
| header_string = "%-5s %-10.10s %s%-15s %-5s %-15s %-5s %5s %5s %s" |
| format_string = "%-5d %-10.10s %s%-15s %-5d %-15s %-5d %5d %5d %.2f" |
| if args.wide: |
| header_string = "%-5s %-16.16s %-2s %-26s %-5s %-26s %-5s %6s %6s %s" |
| format_string = "%-5d %-16.16s %-2s %-26s %-5s %-26s %-5d %6d %6d %.2f" |
| if args.csv: |
| header_string = "%s,%s,%s,%s,%s,%s,%s,%s,%s,%s" |
| format_string = "%d,%s,%s,%s,%s,%s,%d,%d,%d,%.2f" |
| |
| # process event |
| def print_ipv4_event(cpu, data, size): |
| event = ct.cast(data, ct.POINTER(Data_ipv4)).contents |
| global start_ts |
| if args.time: |
| if args.csv: |
| print("%s," % strftime("%H:%M:%S"), end="") |
| else: |
| print("%-8s " % strftime("%H:%M:%S"), end="") |
| if args.timestamp: |
| if start_ts == 0: |
| start_ts = event.ts_us |
| delta_s = (float(event.ts_us) - start_ts) / 1000000 |
| if args.csv: |
| print("%.6f," % delta_s, end="") |
| else: |
| print("%-9.6f " % delta_s, end="") |
| print(format_string % (event.pid, event.task.decode(), |
| "4" if args.wide or args.csv else "", |
| inet_ntop(AF_INET, pack("I", event.saddr)), event.ports >> 32, |
| inet_ntop(AF_INET, pack("I", event.daddr)), event.ports & 0xffffffff, |
| event.tx_b / 1024, event.rx_b / 1024, float(event.span_us) / 1000)) |
| |
| def print_ipv6_event(cpu, data, size): |
| event = ct.cast(data, ct.POINTER(Data_ipv6)).contents |
| global start_ts |
| if args.time: |
| if args.csv: |
| print("%s," % strftime("%H:%M:%S"), end="") |
| else: |
| print("%-8s " % strftime("%H:%M:%S"), end="") |
| if args.timestamp: |
| if start_ts == 0: |
| start_ts = event.ts_us |
| delta_s = (float(event.ts_us) - start_ts) / 1000000 |
| if args.csv: |
| print("%.6f," % delta_s, end="") |
| else: |
| print("%-9.6f " % delta_s, end="") |
| print(format_string % (event.pid, event.task.decode(), |
| "6" if args.wide or args.csv else "", |
| inet_ntop(AF_INET6, event.saddr), event.ports >> 32, |
| inet_ntop(AF_INET6, event.daddr), event.ports & 0xffffffff, |
| event.tx_b / 1024, event.rx_b / 1024, float(event.span_us) / 1000)) |
| |
| # initialize BPF |
| b = BPF(text=bpf_text) |
| |
| # header |
| if args.time: |
| if args.csv: |
| print("%s," % ("TIME"), end="") |
| else: |
| print("%-8s " % ("TIME"), end="") |
| if args.timestamp: |
| if args.csv: |
| print("%s," % ("TIME(s)"), end="") |
| else: |
| print("%-9s " % ("TIME(s)"), end="") |
| print(header_string % ("PID", "COMM", |
| "IP" if args.wide or args.csv else "", "LADDR", |
| "LPORT", "RADDR", "RPORT", "TX_KB", "RX_KB", "MS")) |
| |
| start_ts = 0 |
| |
| # read events |
| b["ipv4_events"].open_perf_buffer(print_ipv4_event, page_cnt=64) |
| b["ipv6_events"].open_perf_buffer(print_ipv6_event, page_cnt=64) |
| while 1: |
| b.kprobe_poll() |