app/dumpcap: add new packet capture application
authorStephen Hemminger <stephen@networkplumber.org>
Wed, 20 Oct 2021 21:42:31 +0000 (14:42 -0700)
committerThomas Monjalon <thomas@monjalon.net>
Fri, 22 Oct 2021 20:40:58 +0000 (22:40 +0200)
This is a new packet capture application to replace existing pdump.
The new application works like Wireshark dumpcap program and supports
the pdump API features.

It is not complete yet some features such as filtering are not implemented.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
MAINTAINERS
app/dumpcap/main.c [new file with mode: 0644]
app/dumpcap/meson.build [new file with mode: 0644]
app/meson.build
doc/guides/howto/img/packet_capture_framework.svg
doc/guides/howto/packet_capture_framework.rst
doc/guides/prog_guide/pdump_lib.rst
doc/guides/rel_notes/release_21_11.rst
doc/guides/tools/dumpcap.rst [new file with mode: 0644]
doc/guides/tools/index.rst

index 578bc2c..d04e3d7 100644 (file)
@@ -1440,6 +1440,8 @@ F: doc/guides/prog_guide/pcapng_lib.rst
 F: app/test/test_pcapng.c
 F: app/pdump/
 F: doc/guides/tools/pdump.rst
+F: app/dumpcap/
+F: doc/guides/tools/dumpcap.rst
 
 
 Packet Framework
diff --git a/app/dumpcap/main.c b/app/dumpcap/main.c
new file mode 100644 (file)
index 0000000..baf9eee
--- /dev/null
@@ -0,0 +1,844 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2019-2020 Microsoft Corporation
+ *
+ * DPDK application to dump network traffic
+ * This is designed to look and act like the Wireshark
+ * dumpcap program.
+ */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <getopt.h>
+#include <inttypes.h>
+#include <limits.h>
+#include <signal.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/queue.h>
+#include <sys/types.h>
+#include <sys/utsname.h>
+#include <time.h>
+#include <unistd.h>
+
+#include <rte_alarm.h>
+#include <rte_bpf.h>
+#include <rte_config.h>
+#include <rte_debug.h>
+#include <rte_eal.h>
+#include <rte_errno.h>
+#include <rte_ethdev.h>
+#include <rte_lcore.h>
+#include <rte_malloc.h>
+#include <rte_mbuf.h>
+#include <rte_mempool.h>
+#include <rte_pcapng.h>
+#include <rte_pdump.h>
+#include <rte_ring.h>
+#include <rte_string_fns.h>
+#include <rte_time.h>
+#include <rte_version.h>
+
+#include <pcap/pcap.h>
+#include <pcap/bpf.h>
+
+#define RING_NAME "capture-ring"
+#define MONITOR_INTERVAL  (500 * 1000)
+#define MBUF_POOL_CACHE_SIZE 32
+#define BURST_SIZE 32
+#define SLEEP_THRESHOLD 1000
+
+/* command line flags */
+static const char *progname;
+static bool quit_signal;
+static bool group_read;
+static bool quiet;
+static bool promiscuous_mode = true;
+static bool use_pcapng = true;
+static char *output_name;
+static const char *filter_str;
+static unsigned int ring_size = 2048;
+static const char *capture_comment;
+static uint32_t snaplen = RTE_MBUF_DEFAULT_BUF_SIZE;
+static bool dump_bpf;
+static struct {
+       uint64_t  duration;     /* nanoseconds */
+       unsigned long packets;  /* number of packets in file */
+       size_t size;            /* file size (bytes) */
+} stop;
+
+/* Running state */
+static struct rte_bpf_prm *bpf_prm;
+static uint64_t start_time, end_time;
+static uint64_t packets_received;
+static size_t file_size;
+
+struct interface {
+       TAILQ_ENTRY(interface) next;
+       uint16_t port;
+       char name[RTE_ETH_NAME_MAX_LEN];
+
+       struct rte_rxtx_callback *rx_cb[RTE_MAX_QUEUES_PER_PORT];
+};
+
+TAILQ_HEAD(interface_list, interface);
+static struct interface_list interfaces = TAILQ_HEAD_INITIALIZER(interfaces);
+static struct interface *port2intf[RTE_MAX_ETHPORTS];
+
+/* Can do either pcap or pcapng format output */
+typedef union {
+       rte_pcapng_t  *pcapng;
+       pcap_dumper_t *dumper;
+} dumpcap_out_t;
+
+static void usage(void)
+{
+       printf("Usage: %s [options] ...\n\n", progname);
+       printf("Capture Interface:\n"
+              "  -i <interface>           name or port index of interface\n"
+              "  -f <capture filter>      packet filter in libpcap filter syntax\n");
+       printf("  -s <snaplen>, --snapshot-length <snaplen>\n"
+              "                           packet snapshot length (def: %u)\n",
+              RTE_MBUF_DEFAULT_BUF_SIZE);
+       printf("  -p, --no-promiscuous-mode\n"
+              "                           don't capture in promiscuous mode\n"
+              "  -D, --list-interfaces    print list of interfaces and exit\n"
+              "  -d                       print generated BPF code for capture filter\n"
+              "\n"
+              "Stop conditions:\n"
+              "  -c <packet count>        stop after n packets (def: infinite)\n"
+              "  -a <autostop cond.> ..., --autostop <autostop cond.> ...\n"
+              "                           duration:NUM - stop after NUM seconds\n"
+              "                           filesize:NUM - stop this file after NUM kB\n"
+              "                            packets:NUM - stop after NUM packets\n"
+              "Output (files):\n"
+              "  -w <filename>            name of file to save (def: tempfile)\n"
+              "  -g                       enable group read access on the output file(s)\n"
+              "  -n                       use pcapng format instead of pcap (default)\n"
+              "  -P                       use libpcap format instead of pcapng\n"
+              "  --capture-comment <comment>\n"
+              "                           add a capture comment to the output file\n"
+              "\n"
+              "Miscellaneous:\n"
+              "  -q                       don't report packet capture counts\n"
+              "  -v, --version            print version information and exit\n"
+              "  -h, --help               display this help and exit\n"
+              "\n"
+              "Use Ctrl-C to stop capturing at any time.\n");
+}
+
+static const char *version(void)
+{
+       static char str[128];
+
+       snprintf(str, sizeof(str),
+                "%s 1.0 (%s)\n", progname, rte_version());
+       return str;
+}
+
+/* Parse numeric argument from command line */
+static unsigned long get_uint(const char *arg, const char *name,
+                            unsigned int limit)
+{
+       unsigned long u;
+       char *endp;
+
+       u = strtoul(arg, &endp, 0);
+       if (*arg == '\0' || *endp != '\0')
+               rte_exit(EXIT_FAILURE,
+                        "Specified %s \"%s\" is not a valid number\n",
+                        name, arg);
+       if (limit && u > limit)
+               rte_exit(EXIT_FAILURE,
+                        "Specified %s \"%s\" is too large (greater than %u)\n",
+                        name, arg, limit);
+
+       return u;
+}
+
+/* Set auto stop values */
+static void auto_stop(char *opt)
+{
+       char *value, *endp;
+
+       value = strchr(opt, ':');
+       if (value == NULL)
+               rte_exit(EXIT_FAILURE,
+                        "Missing colon in auto stop parameter\n");
+
+       *value++ = '\0';
+       if (strcmp(opt, "duration") == 0) {
+               double interval = strtod(value, &endp);
+
+               if (*value == '\0' || *endp != '\0' || interval <= 0)
+                       rte_exit(EXIT_FAILURE,
+                                "Invalid duration \"%s\"\n", value);
+               stop.duration = NSEC_PER_SEC * interval;
+       } else if (strcmp(opt, "filesize") == 0) {
+               stop.size = get_uint(value, "filesize", 0) * 1024;
+       } else if (strcmp(opt, "packets") == 0) {
+               stop.packets = get_uint(value, "packets", 0);
+       } else {
+               rte_exit(EXIT_FAILURE,
+                        "Unknown autostop parameter \"%s\"\n", opt);
+       }
+}
+
+/* Add interface to list of interfaces to capture */
+static void add_interface(uint16_t port, const char *name)
+{
+       struct interface *intf;
+
+       intf = malloc(sizeof(*intf));
+       if (!intf)
+               rte_exit(EXIT_FAILURE, "no memory for interface\n");
+
+       memset(intf, 0, sizeof(*intf));
+       rte_strscpy(intf->name, name, sizeof(intf->name));
+
+       printf("Capturing on '%s'\n", name);
+
+       port2intf[port] = intf;
+       TAILQ_INSERT_TAIL(&interfaces, intf, next);
+}
+
+/* Select all valid DPDK interfaces */
+static void select_all_interfaces(void)
+{
+       char name[RTE_ETH_NAME_MAX_LEN];
+       uint16_t p;
+
+       RTE_ETH_FOREACH_DEV(p) {
+               if (rte_eth_dev_get_name_by_port(p, name) < 0)
+                       continue;
+               add_interface(p, name);
+       }
+}
+
+/*
+ * Choose interface to capture if no -i option given.
+ * Select the first DPDK port, this matches what dumpcap does.
+ */
+static void set_default_interface(void)
+{
+       char name[RTE_ETH_NAME_MAX_LEN];
+       uint16_t p;
+
+       RTE_ETH_FOREACH_DEV(p) {
+               if (rte_eth_dev_get_name_by_port(p, name) < 0)
+                       continue;
+               add_interface(p, name);
+               return;
+       }
+       rte_exit(EXIT_FAILURE, "No usable interfaces found\n");
+}
+
+/* Lookup interface by name or port and add it to the list */
+static void select_interface(const char *arg)
+{
+       uint16_t port;
+
+       if (strcmp(arg, "*"))
+               select_all_interfaces();
+       else if (rte_eth_dev_get_port_by_name(arg, &port) == 0)
+               add_interface(port, arg);
+       else {
+               char name[RTE_ETH_NAME_MAX_LEN];
+
+               port = get_uint(arg, "port_number", UINT16_MAX);
+               if (rte_eth_dev_get_name_by_port(port, name) < 0)
+                       rte_exit(EXIT_FAILURE, "Invalid port number %u\n",
+                                port);
+               add_interface(port, name);
+       }
+}
+
+/* Display list of possible interfaces that can be used. */
+static void show_interfaces(void)
+{
+       char name[RTE_ETH_NAME_MAX_LEN];
+       uint16_t p;
+
+       RTE_ETH_FOREACH_DEV(p) {
+               if (rte_eth_dev_get_name_by_port(p, name) < 0)
+                       continue;
+               printf("%u. %s\n", p, name);
+       }
+}
+
+static void compile_filter(void)
+{
+       struct bpf_program bf;
+       pcap_t *pcap;
+
+       pcap = pcap_open_dead(DLT_EN10MB, snaplen);
+       if (!pcap)
+               rte_exit(EXIT_FAILURE, "can not open pcap\n");
+
+       if (pcap_compile(pcap, &bf, filter_str,
+                        1, PCAP_NETMASK_UNKNOWN) != 0)
+               rte_exit(EXIT_FAILURE, "pcap filter string not valid (%s)\n",
+                        pcap_geterr(pcap));
+
+       bpf_prm = rte_bpf_convert(&bf);
+       if (bpf_prm == NULL)
+               rte_exit(EXIT_FAILURE,
+                        "bpf convert failed\n");
+
+       if (dump_bpf) {
+               printf("cBPF program (%u insns)\n", bf.bf_len);
+               bpf_dump(&bf, 1);
+               printf("\neBPF program (%u insns)\n", bpf_prm->nb_ins);
+               rte_bpf_dump(stdout, bpf_prm->ins, bpf_prm->nb_ins);
+               exit(0);
+       }
+
+       /* Don't care about original program any more */
+       pcap_freecode(&bf);
+       pcap_close(pcap);
+}
+
+/*
+ * Parse command line options.
+ * These are chosen to be similar to dumpcap command.
+ */
+static void parse_opts(int argc, char **argv)
+{
+       static const struct option long_options[] = {
+               { "autostop",        required_argument, NULL, 'a' },
+               { "capture-comment", required_argument, NULL, 0 },
+               { "help",            no_argument,       NULL, 'h' },
+               { "interface",       required_argument, NULL, 'i' },
+               { "list-interfaces", no_argument,       NULL, 'D' },
+               { "no-promiscuous-mode", no_argument,   NULL, 'p' },
+               { "output-file",     required_argument, NULL, 'w' },
+               { "ring-buffer",     required_argument, NULL, 'b' },
+               { "snapshot-length", required_argument, NULL, 's' },
+               { "version",         no_argument,       NULL, 'v' },
+               { NULL },
+       };
+       int option_index, c;
+
+       for (;;) {
+               c = getopt_long(argc, argv, "a:b:c:dDf:ghi:nN:pPqs:vw:",
+                               long_options, &option_index);
+               if (c == -1)
+                       break;
+
+               switch (c) {
+               case 0:
+                       switch (option_index) {
+                       case 0:
+                               capture_comment = optarg;
+                               break;
+                       default:
+                               usage();
+                               exit(1);
+                       }
+                       break;
+               case 'a':
+                       auto_stop(optarg);
+                       break;
+               case 'b':
+                       rte_exit(EXIT_FAILURE,
+                                "multiple files not implemented\n");
+                       break;
+               case 'c':
+                       stop.packets = get_uint(optarg, "packet_count", 0);
+                       break;
+               case 'd':
+                       dump_bpf = true;
+                       break;
+               case 'D':
+                       show_interfaces();
+                       exit(0);
+               case 'f':
+                       filter_str = optarg;
+                       break;
+               case 'g':
+                       group_read = true;
+                       break;
+               case 'h':
+                       printf("%s\n\n", version());
+                       usage();
+                       exit(0);
+               case 'i':
+                       select_interface(optarg);
+                       break;
+               case 'n':
+                       use_pcapng = true;
+                       break;
+               case 'N':
+                       ring_size = get_uint(optarg, "packet_limit", 0);
+                       break;
+               case 'p':
+                       promiscuous_mode = false;
+                       break;
+               case 'P':
+                       use_pcapng = false;
+                       break;
+               case 'q':
+                       quiet = true;
+                       break;
+               case 's':
+                       snaplen = get_uint(optarg, "snap_len", 0);
+                       break;
+               case 'w':
+                       output_name = optarg;
+                       break;
+               case 'v':
+                       printf("%s\n", version());
+                       exit(0);
+               default:
+                       fprintf(stderr, "Invalid option: %s\n",
+                               argv[optind - 1]);
+                       usage();
+                       exit(1);
+               }
+       }
+}
+
+static void
+signal_handler(int sig_num __rte_unused)
+{
+       __atomic_store_n(&quit_signal, true, __ATOMIC_RELAXED);
+}
+
+/* Return the time since 1/1/1970 in nanoseconds */
+static uint64_t create_timestamp(void)
+{
+       struct timespec now;
+
+       clock_gettime(CLOCK_MONOTONIC, &now);
+       return rte_timespec_to_ns(&now);
+}
+
+static void
+cleanup_pdump_resources(void)
+{
+       struct interface *intf;
+
+       TAILQ_FOREACH(intf, &interfaces, next) {
+               rte_pdump_disable(intf->port,
+                                 RTE_PDUMP_ALL_QUEUES, RTE_PDUMP_FLAG_RXTX);
+               if (promiscuous_mode)
+                       rte_eth_promiscuous_disable(intf->port);
+       }
+}
+
+/* Alarm signal handler, used to check that primary process */
+static void
+monitor_primary(void *arg __rte_unused)
+{
+       if (__atomic_load_n(&quit_signal, __ATOMIC_RELAXED))
+               return;
+
+       if (rte_eal_primary_proc_alive(NULL)) {
+               rte_eal_alarm_set(MONITOR_INTERVAL, monitor_primary, NULL);
+       } else {
+               fprintf(stderr,
+                       "Primary process is no longer active, exiting...\n");
+               __atomic_store_n(&quit_signal, true, __ATOMIC_RELAXED);
+       }
+}
+
+/* Setup handler to check when primary exits. */
+static void
+enable_primary_monitor(void)
+{
+       int ret;
+
+       /* Once primary exits, so will pdump. */
+       ret = rte_eal_alarm_set(MONITOR_INTERVAL, monitor_primary, NULL);
+       if (ret < 0)
+               fprintf(stderr, "Fail to enable monitor:%d\n", ret);
+}
+
+static void
+disable_primary_monitor(void)
+{
+       int ret;
+
+       ret = rte_eal_alarm_cancel(monitor_primary, NULL);
+       if (ret < 0)
+               fprintf(stderr, "Fail to disable monitor:%d\n", ret);
+}
+
+static void
+report_packet_stats(dumpcap_out_t out)
+{
+       struct rte_pdump_stats pdump_stats;
+       struct interface *intf;
+       uint64_t ifrecv, ifdrop;
+       double percent;
+
+       fputc('\n', stderr);
+       TAILQ_FOREACH(intf, &interfaces, next) {
+               if (rte_pdump_stats(intf->port, &pdump_stats) < 0)
+                       continue;
+
+               /* do what Wiretap does */
+               ifrecv = pdump_stats.accepted + pdump_stats.filtered;
+               ifdrop = pdump_stats.nombuf + pdump_stats.ringfull;
+
+               if (use_pcapng)
+                       rte_pcapng_write_stats(out.pcapng, intf->port, NULL,
+                                              start_time, end_time,
+                                              ifrecv, ifdrop);
+
+               if (ifrecv == 0)
+                       percent = 0;
+               else
+                       percent = 100. * ifrecv / (ifrecv + ifdrop);
+
+               fprintf(stderr,
+                       "Packets received/dropped on interface '%s': "
+                       "%"PRIu64 "/%" PRIu64 " (%.1f)\n",
+                       intf->name, ifrecv, ifdrop, percent);
+       }
+}
+
+/*
+ * Start DPDK EAL with arguments.
+ * Unlike most DPDK programs, this application does not use the
+ * typical EAL command line arguments.
+ * We don't want to expose all the DPDK internals to the user.
+ */
+static void dpdk_init(void)
+{
+       static const char * const args[] = {
+               "dumpcap", "--proc-type", "secondary",
+               "--log-level", "notice"
+
+       };
+       const int eal_argc = RTE_DIM(args);
+       char **eal_argv;
+       unsigned int i;
+
+       /* DPDK API requires mutable versions of command line arguments. */
+       eal_argv = calloc(eal_argc + 1, sizeof(char *));
+       if (eal_argv == NULL)
+               rte_panic("No memory\n");
+
+       eal_argv[0] = strdup(progname);
+       for (i = 1; i < RTE_DIM(args); i++)
+               eal_argv[i] = strdup(args[i]);
+
+       if (rte_eal_init(eal_argc, eal_argv) < 0)
+               rte_exit(EXIT_FAILURE, "EAL init failed: is primary process running?\n");
+
+       if (rte_eth_dev_count_avail() == 0)
+               rte_exit(EXIT_FAILURE, "No Ethernet ports found\n");
+}
+
+/* Create packet ring shared between callbacks and process */
+static struct rte_ring *create_ring(void)
+{
+       struct rte_ring *ring;
+       size_t size, log2;
+
+       /* Find next power of 2 >= size. */
+       size = ring_size;
+       log2 = sizeof(size) * 8 - __builtin_clzl(size - 1);
+       size = 1u << log2;
+
+       if (size != ring_size) {
+               fprintf(stderr, "Ring size %u rounded up to %zu\n",
+                       ring_size, size);
+               ring_size = size;
+       }
+
+       ring = rte_ring_lookup(RING_NAME);
+       if (ring == NULL) {
+               ring = rte_ring_create(RING_NAME, ring_size,
+                                       rte_socket_id(), 0);
+               if (ring == NULL)
+                       rte_exit(EXIT_FAILURE, "Could not create ring :%s\n",
+                                rte_strerror(rte_errno));
+       }
+       return ring;
+}
+
+static struct rte_mempool *create_mempool(void)
+{
+       static const char pool_name[] = "capture_mbufs";
+       size_t num_mbufs = 2 * ring_size;
+       struct rte_mempool *mp;
+
+       mp = rte_mempool_lookup(pool_name);
+       if (mp)
+               return mp;
+
+       mp = rte_pktmbuf_pool_create_by_ops(pool_name, num_mbufs,
+                                           MBUF_POOL_CACHE_SIZE, 0,
+                                           rte_pcapng_mbuf_size(snaplen),
+                                           rte_socket_id(), "ring_mp_sc");
+       if (mp == NULL)
+               rte_exit(EXIT_FAILURE,
+                        "Mempool (%s) creation failed: %s\n", pool_name,
+                        rte_strerror(rte_errno));
+
+       return mp;
+}
+
+/*
+ * Get Operating System information.
+ * Returns an string allocated via malloc().
+ */
+static char *get_os_info(void)
+{
+       struct utsname uts;
+       char *osname = NULL;
+
+       if (uname(&uts) < 0)
+               return NULL;
+
+       if (asprintf(&osname, "%s %s",
+                    uts.sysname, uts.release) == -1)
+               return NULL;
+
+       return osname;
+}
+
+static dumpcap_out_t create_output(void)
+{
+       dumpcap_out_t ret;
+       static char tmp_path[PATH_MAX];
+       int fd;
+
+       /* If no filename specified make a tempfile name */
+       if (output_name == NULL) {
+               struct interface *intf;
+               struct tm *tm;
+               time_t now;
+               char ts[32];
+
+               intf = TAILQ_FIRST(&interfaces);
+               now = time(NULL);
+               tm = localtime(&now);
+               if (!tm)
+                       rte_panic("localtime failed\n");
+
+               strftime(ts, sizeof(ts), "%Y%m%d%H%M%S", tm);
+
+               snprintf(tmp_path, sizeof(tmp_path),
+                        "/tmp/%s_%u_%s_%s.%s",
+                        progname, intf->port, intf->name, ts,
+                        use_pcapng ? "pcapng" : "pcap");
+               output_name = tmp_path;
+       }
+
+       if (strcmp(output_name, "-") == 0)
+               fd = STDOUT_FILENO;
+       else {
+               mode_t mode = group_read ? 0640 : 0600;
+
+               fd = open(output_name, O_WRONLY | O_CREAT, mode);
+               if (fd < 0)
+                       rte_exit(EXIT_FAILURE, "Can not open \"%s\": %s\n",
+                                output_name, strerror(errno));
+       }
+
+       if (use_pcapng) {
+               char *os = get_os_info();
+
+               ret.pcapng = rte_pcapng_fdopen(fd, os, NULL,
+                                          version(), capture_comment);
+               if (ret.pcapng == NULL)
+                       rte_exit(EXIT_FAILURE, "pcapng_fdopen failed: %s\n",
+                                strerror(rte_errno));
+               free(os);
+       } else {
+               pcap_t *pcap;
+
+               pcap = pcap_open_dead_with_tstamp_precision(DLT_EN10MB, snaplen,
+                                                           PCAP_TSTAMP_PRECISION_NANO);
+               if (pcap == NULL)
+                       rte_exit(EXIT_FAILURE, "pcap_open_dead failed\n");
+
+               ret.dumper = pcap_dump_fopen(pcap, fdopen(fd, "w"));
+               if (ret.dumper == NULL)
+                       rte_exit(EXIT_FAILURE, "pcap_dump_fopen failed: %s\n",
+                                pcap_geterr(pcap));
+       }
+
+       return ret;
+}
+
+static void enable_pdump(struct rte_ring *r, struct rte_mempool *mp)
+{
+       struct interface *intf;
+       uint32_t flags;
+       int ret;
+
+       flags = RTE_PDUMP_FLAG_RXTX;
+       if (use_pcapng)
+               flags |= RTE_PDUMP_FLAG_PCAPNG;
+
+       TAILQ_FOREACH(intf, &interfaces, next) {
+               if (promiscuous_mode)
+                       rte_eth_promiscuous_enable(intf->port);
+
+               ret = rte_pdump_enable_bpf(intf->port, RTE_PDUMP_ALL_QUEUES,
+                                          flags, snaplen,
+                                          r, mp, bpf_prm);
+               if (ret < 0)
+                       rte_exit(EXIT_FAILURE,
+                                "Packet dump enable failed: %s\n",
+                                rte_strerror(-ret));
+       }
+}
+
+/*
+ * Show current count of captured packets
+ * with backspaces to overwrite last value.
+ */
+static void show_count(uint64_t count)
+{
+       unsigned int i;
+       static unsigned int bt;
+
+       for (i = 0; i < bt; i++)
+               fputc('\b', stderr);
+
+       bt = fprintf(stderr, "%"PRIu64" ", count);
+}
+
+/* Write multiple packets in older pcap format */
+static ssize_t
+pcap_write_packets(pcap_dumper_t *dumper,
+                  struct rte_mbuf *pkts[], uint16_t n)
+{
+       uint8_t temp_data[snaplen];
+       struct pcap_pkthdr header;
+       uint16_t i;
+       size_t total = 0;
+
+       gettimeofday(&header.ts, NULL);
+
+       for (i = 0; i < n; i++) {
+               struct rte_mbuf *m = pkts[i];
+
+               header.len = rte_pktmbuf_pkt_len(m);
+               header.caplen = RTE_MIN(header.len, snaplen);
+
+               pcap_dump((u_char *)dumper, &header,
+                         rte_pktmbuf_read(m, 0, header.caplen, temp_data));
+
+               total += sizeof(header) + header.len;
+       }
+
+       return total;
+}
+
+/* Process all packets in ring and dump to capture file */
+static int process_ring(dumpcap_out_t out, struct rte_ring *r)
+{
+       struct rte_mbuf *pkts[BURST_SIZE];
+       unsigned int avail, n;
+       static unsigned int empty_count;
+       ssize_t written;
+
+       n = rte_ring_sc_dequeue_burst(r, (void **) pkts, BURST_SIZE,
+                                     &avail);
+       if (n == 0) {
+               /* don't consume endless amounts of cpu if idle */
+               if (empty_count < SLEEP_THRESHOLD)
+                       ++empty_count;
+               else
+                       usleep(10);
+               return 0;
+       }
+
+       empty_count = (avail == 0);
+
+       if (use_pcapng)
+               written = rte_pcapng_write_packets(out.pcapng, pkts, n);
+       else
+               written = pcap_write_packets(out.dumper, pkts, n);
+
+       rte_pktmbuf_free_bulk(pkts, n);
+
+       if (written < 0)
+               return -1;
+
+       file_size += written;
+       packets_received += n;
+       if (!quiet)
+               show_count(packets_received);
+
+       return 0;
+}
+
+int main(int argc, char **argv)
+{
+       struct rte_ring *r;
+       struct rte_mempool *mp;
+       dumpcap_out_t out;
+
+       progname = argv[0];
+
+       dpdk_init();
+       parse_opts(argc, argv);
+
+       if (filter_str)
+               compile_filter();
+
+       if (TAILQ_EMPTY(&interfaces))
+               set_default_interface();
+
+       r = create_ring();
+       mp = create_mempool();
+       out = create_output();
+
+       start_time = create_timestamp();
+       enable_pdump(r, mp);
+
+       signal(SIGINT, signal_handler);
+       signal(SIGPIPE, SIG_IGN);
+
+       enable_primary_monitor();
+
+       if (!quiet) {
+               fprintf(stderr, "Packets captured: ");
+               show_count(0);
+       }
+
+       while (!__atomic_load_n(&quit_signal, __ATOMIC_RELAXED)) {
+               if (process_ring(out, r) < 0) {
+                       fprintf(stderr, "pcapng file write failed; %s\n",
+                               strerror(errno));
+                       break;
+               }
+
+               if (stop.size && file_size >= stop.size)
+                       break;
+
+               if (stop.packets && packets_received >= stop.packets)
+                       break;
+
+               if (stop.duration != 0 &&
+                   create_timestamp() - start_time > stop.duration)
+                       break;
+       }
+
+       end_time = create_timestamp();
+       disable_primary_monitor();
+
+       if (rte_eal_primary_proc_alive(NULL))
+               report_packet_stats(out);
+
+       if (use_pcapng)
+               rte_pcapng_close(out.pcapng);
+       else
+               pcap_dump_close(out.dumper);
+
+       cleanup_pdump_resources();
+       rte_free(bpf_filter);
+       rte_ring_free(r);
+       rte_mempool_free(mp);
+
+       return rte_eal_cleanup() ? EXIT_FAILURE : 0;
+}
diff --git a/app/dumpcap/meson.build b/app/dumpcap/meson.build
new file mode 100644 (file)
index 0000000..ad4fc6a
--- /dev/null
@@ -0,0 +1,16 @@
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright(c) 2019 Microsoft Corporation
+
+if not dpdk_conf.has('RTE_PORT_PCAP')
+    build = false
+    reason = 'missing dependency, "libpcap"'
+endif
+
+if is_windows
+    build = false
+    reason = 'not supported on Windows'
+    subdir_done()
+endif
+
+sources = files('main.c')
+deps += ['ethdev', 'pdump', 'pcapng', 'bpf']
index 4c60498..e41a2e3 100644 (file)
@@ -2,6 +2,7 @@
 # Copyright(c) 2017-2019 Intel Corporation
 
 apps = [
+        'dumpcap',
         'pdump',
         'proc-info',
         'test-acl',
index a76baf7..1c2646a 100644 (file)
@@ -1,6 +1,4 @@
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index 9fc0dc9..24d4bd0 100644 (file)
@@ -14,7 +14,7 @@ and enhanced in 21.11.
 The DPDK packet capture framework consists of the libraries
 for collecting packets ``librte_pdump``
 and writing packets to a file ``librte_pcapng``.
-There is an application: ``dpdk-pdump``.
+There are two sample applications: ``dpdk-dumpcap`` and older ``dpdk-pdump``.
 
 Introduction
 ------------
@@ -28,37 +28,48 @@ and its usage is recommended for debugging purposes.
 The :doc:`librte_pcapng <../prog_guide/pcapng_lib>` library provides the API
 to format packets and write them to a file in Pcapng format.
 
-The application which initializes the packet capture framework will be a primary process
-and the application that enables or disables the packet capture will
-be a secondary process. The primary process sends the Rx and Tx packets from the DPDK ports
-to the secondary process.
-
-In DPDK the ``testpmd`` application can be used to initialize the packet
-capture framework and acts as a server, and the ``dpdk-pdump`` tool acts as a
-client. To view Rx or Tx packets of ``testpmd``, the application should be
-launched first, and then the ``dpdk-pdump`` tool. Packets from ``testpmd``
-will be sent to the tool, which then sends them on to the Pcap PMD device and
-that device writes them to the Pcap file or to an external interface depending
-on the command-line option used.
+The :doc:`dpdk-dumpcap <../tools/dumpcap>` is a tool that captures packets in
+like Wireshark dumpcap does for Linux.
+It runs as a DPDK secondary process and captures packets
+from one or more interfaces and writes them to a file in Pcapng format.
+The ``dpdk-dumpcap`` tool is designed to take
+most of the same options as the Wireshark ``dumpcap`` command.
+
+Without any options it will use the packet capture framework
+to capture traffic from the first available DPDK port.
+
+The ``dpdk-testpmd`` application can be used to initialize
+the packet capture framework and acts as a server,
+and the ``dpdk-dumpcap`` tool acts as a client.
+To view Rx or Tx packets of ``dpdk-testpmd``,
+the application should be launched first,
+and then the ``dpdk-dumpcap`` tool.
+Packets from ``dpdk-testpmd`` will be sent to the tool,
+and then to the Pcapng file.
 
 Some things to note:
 
-* The ``dpdk-pdump`` tool can only be used in conjunction with a primary
+* All tools using ``librte_pdump`` can only be used in conjunction with a primary
   application which has the packet capture framework initialized already. In
   dpdk, only ``testpmd`` is modified to initialize packet capture framework,
-  other applications remain untouched. So, if the ``dpdk-pdump`` tool has to
+  other applications remain untouched. So, if the ``dpdk-dumpcap`` tool has to
   be used with any application other than the testpmd, the user needs to
   explicitly modify that application to call the packet capture framework
   initialization code. Refer to the ``app/test-pmd/testpmd.c`` code and look
   for ``pdump`` keyword to see how this is done.
 
-* The ``dpdk-pdump`` tool depends on the libpcap based PMD.
+* The ``dpdk-pdump`` tool is an older tool
+  created as demonstration of ``librte_pdump`` library.
+  The ``dpdk-pdump`` tool provides more limited functionality
+  and depends on the Pcap PMD.
+  It is retained only for compatibility reasons;
+  users should use ``dpdk-dumpcap`` instead.
 
 
 Test Environment
 ----------------
 
-The overview of using the Packet Capture Framework and the ``dpdk-pdump`` tool
+The overview of using the Packet Capture Framework and the ``dpdk-dumpcap`` utility
 for packet capturing on the DPDK port in
 :numref:`figure_packet_capture_framework`.
 
@@ -66,13 +77,13 @@ for packet capturing on the DPDK port in
 
 .. figure:: img/packet_capture_framework.*
 
-   Packet capturing on a DPDK port using the dpdk-pdump tool.
+   Packet capturing on a DPDK port using the dpdk-dumpcap utility.
 
 
 Running the Application
 -----------------------
 
-The following steps demonstrate how to run the ``dpdk-pdump`` tool to capture
+The following steps demonstrate how to run the ``dpdk-dumpcap`` tool to capture
 Rx side packets on dpdk_port0 in :numref:`figure_packet_capture_framework` and
 inspect them using ``tcpdump``.
 
@@ -80,16 +91,15 @@ inspect them using ``tcpdump``.
 
      sudo <build_dir>/app/dpdk-testpmd -c 0xf0 -n 4 -- -i --port-topology=chained
 
-#. Launch the pdump tool as follows::
+#. Launch the dpdk-dumpcap as follows::
 
-     sudo <build_dir>/app/dpdk-pdump -- \
-          --pdump 'port=0,queue=*,rx-dev=/tmp/capture.pcap'
+     sudo <build_dir>/app/dpdk-dumpcap -w /tmp/capture.pcapng
 
 #. Send traffic to dpdk_port0 from traffic generator.
-   Inspect packets captured in the file capture.pcap using a tool
-   that can interpret Pcap files, for example tcpdump::
+   Inspect packets captured in the file capture.pcapng using a tool
+   such as tcpdump or tshark that can interpret Pcapng files::
 
-     $tcpdump -nr /tmp/capture.pcap
+     $ tcpdump -nr /tmp/capture.pcapng
      reading from file /tmp/capture.pcap, link-type EN10MB (Ethernet)
      11:11:36.891404 IP 4.4.4.4.whois++ > 3.3.3.3.whois++: UDP, length 18
      11:11:36.891442 IP 4.4.4.4.whois++ > 3.3.3.3.whois++: UDP, length 18
index ea1b2f9..07b9f39 100644 (file)
@@ -89,5 +89,5 @@ function.
 Use Case: Packet Capturing
 --------------------------
 
-The DPDK ``app/pdump`` tool is developed based on this library to capture packets in DPDK.
-Users can use this as an example to develop their own packet capturing tools.
+The DPDK ``app/dpdk-dumpcap`` utility uses this library
+to capture packets in DPDK.
index 80abfaa..c0fded3 100644 (file)
@@ -242,6 +242,10 @@ New Features
 
 * **Revised packet capture framework.**
 
+  * New dpdk-dumpcap program that has most of the features
+    of the wireshark dumpcap utility including:
+    capture of multiple interfaces, filtering,
+    and stopping after number of bytes, packets.
   * New library for writing pcapng packet capture files.
   * Enhancements to the pdump library to support:
     * Packet filter with BPF.
diff --git a/doc/guides/tools/dumpcap.rst b/doc/guides/tools/dumpcap.rst
new file mode 100644 (file)
index 0000000..6fa2843
--- /dev/null
@@ -0,0 +1,90 @@
+..  SPDX-License-Identifier: BSD-3-Clause
+    Copyright(c) 2020 Microsoft Corporation.
+
+dpdk-dumpcap Application
+========================
+
+The ``dpdk-dumpcap`` tool is a Data Plane Development Kit (DPDK)
+network traffic dump tool.
+The interface is similar to the dumpcap tool in Wireshark.
+It runs as a secondary DPDK process and lets you capture packets
+that are coming into and out of a DPDK primary process.
+The ``dpdk-dumpcap`` writes files in Pcapng packet format.
+
+Without any options set, it will use DPDK to capture traffic
+from the first available DPDK interface
+and write the received raw packet data,
+along with timestamps into a pcapng file.
+
+If the ``-w`` option is not specified, ``dpdk-dumpcap`` writes
+to a newly created file with a name chosen
+based on interface name and timestamp.
+If ``-w`` option is specified, then that file is used.
+
+.. note::
+
+   * The ``dpdk-dumpcap`` tool can only be used in conjunction with a primary
+     application which has the packet capture framework initialized already.
+     In DPDK, only the ``dpdk-testpmd`` is modified to initialize
+     packet capture framework, other applications remain untouched.
+     So, if the ``dpdk-dumpcap`` tool has to be used with any application
+     other than the ``dpdk-testpmd``, user needs to explicitly modify
+     that application to call packet capture framework initialization code.
+     Refer ``app/test-pmd/testpmd.c`` code to see how this is done.
+
+   * The ``dpdk-dumpcap`` tool runs as a DPDK secondary process.
+     It exits when the primary application exits.
+
+
+Running the Application
+-----------------------
+
+To list interfaces available for capture, use ``--list-interfaces``.
+
+To filter packets in style of *tshark*, use the ``-f`` flag.
+
+To capture on multiple interfaces at once, use multiple ``-I`` flags.
+
+
+Example
+-------
+
+.. code-block:: console
+
+   # <build_dir>/app/dpdk-dumpcap --list-interfaces
+   0. 000:00:03.0
+   1. 000:00:03.1
+
+   # <build_dir>/app/dpdk-dumpcap -I 0000:00:03.0 -c 6 -w /tmp/sample.pcapng
+   Packets captured: 6
+   Packets received/dropped on interface '0000:00:03.0' 6/0
+
+   # <build_dir>/app/dpdk-dumpcap -f 'tcp port 80'
+   Packets captured: 6
+   Packets received/dropped on interface '0000:00:03.0' 10/8
+
+
+Limitations
+-----------
+
+The following option of Wireshark ``dumpcap`` is not yet implemented:
+
+   * ``-b|--ring-buffer`` -- more complex file management.
+
+The following options do not make sense in the context of DPDK.
+
+   * ``-C <byte_limit>`` -- it's a kernel thing.
+
+   * ``-t`` -- use a thread per interface.
+
+   * Timestamp type.
+
+   * Link data types. Only EN10MB (Ethernet) is supported.
+
+   * Wireless related options: ``-I|--monitor-mode`` and  ``-k <freq>``
+
+
+.. note::
+
+   * The options to ``dpdk-dumpcap`` are like the Wireshark dumpcap program
+     and are not the same as ``dpdk-pdump`` and other DPDK applications.
index 93dde41..0e5041a 100644 (file)
@@ -8,11 +8,12 @@ DPDK Tools User Guides
     :maxdepth: 2
     :numbered:
 
-    proc_info
-    pdump
-    pmdinfo
     hugepages
     devbind
+    proc_info
+    pmdinfo
+    dumpcap
+    pdump
     flow-perf
     testbbdev
     cryptoperf