Re: [PATCH v3 1/3] tools: Add initial code for btmon-logger

[Szymon Janc <szymon.janc@codecoup.pl>]

On Monday, 19 February 2018 14:46:06 CET Szymon Janc wrote:
> This is intended for use for automated logging or unatrended systems.
> It doesn't contain any packet decoding functionality which results
> in much smaller binary.
> ---
>  .gitignore           |   1 +
>  Makefile.tools       |   5 +
>  tools/btmon-logger.c | 350
> +++++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 356
> insertions(+)
>  create mode 100644 tools/btmon-logger.c
> 
> diff --git a/.gitignore b/.gitignore
> index 47808059b..33ec66048 100644
> --- a/.gitignore
> +++ b/.gitignore
> @@ -118,6 +118,7 @@ tools/btconfig
>  tools/btmgmt
>  tools/btsnoop
>  tools/btpclient
> +tools/btmon-logger
>  peripheral/btsensor
>  monitor/btmon
>  emulator/btvirt
> diff --git a/Makefile.tools b/Makefile.tools
> index 71d083e71..ba4b9b7d7 100644
> --- a/Makefile.tools
> +++ b/Makefile.tools
> @@ -62,6 +62,11 @@ monitor_btmon_SOURCES = monitor/main.c monitor/bt.h \
>  				monitor/tty.h
>  monitor_btmon_LDADD = lib/libbluetooth-internal.la \
>  				src/libshared-mainloop.la @UDEV_LIBS@
> +
> +noinst_PROGRAMS += tools/btmon-logger
> +
> +tools_btmon_logger_SOURCES = tools/btmon-logger.c lib/monitor.h
> +tools_btmon_logger_LDADD = src/libshared-mainloop.la
>  endif
> 
>  if TESTING
> diff --git a/tools/btmon-logger.c b/tools/btmon-logger.c
> new file mode 100644
> index 000000000..9787e6b03
> --- /dev/null
> +++ b/tools/btmon-logger.c
> @@ -0,0 +1,350 @@
> +/*
> + *
> + *  BlueZ - Bluetooth protocol stack for Linux
> + *
> + *  Copyright (C) 2017-2018  Codecoup
> + *  Copyright (C) 2011-2014  Intel Corporation
> + *  Copyright (C) 2002-2010  Marcel Holtmann <marcel@holtmann.org>
> + *
> + *
> + *  This program is free software; you can redistribute it and/or modify
> + *  it under the terms of 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.
> + *
> + *  This program 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 a copy of the GNU General Public License
> + *  along with this program; if not, write to the Free Software
> + *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 
> USA + *
> + */
> +
> +#ifdef HAVE_CONFIG_H
> +#include <config.h>
> +#endif
> +
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <limits.h>
> +#include <string.h>
> +#include <time.h>
> +#include <getopt.h>
> +#include <unistd.h>
> +#include <sys/socket.h>
> +
> +#include "lib/bluetooth.h"
> +#include "lib/hci.h"
> +
> +#include "src/shared/util.h"
> +#include "src/shared/mainloop.h"
> +#include "src/shared/btsnoop.h"
> +
> +#define MONITOR_INDEX_NONE 0xffff
> +
> +struct monitor_hdr {
> +	uint16_t opcode;
> +	uint16_t index;
> +	uint16_t len;
> +} __attribute__ ((packed));
> +
> +struct btsnoop_hdr {
> +	uint8_t		id[8];		/* Identification Pattern */
> +	uint32_t	version;	/* Version Number = 1 */
> +	uint32_t	type;		/* Datalink Type */
> +} __attribute__ ((packed));
> +#define BTSNOOP_HDR_SIZE (sizeof(struct btsnoop_hdr))
> +
> +struct btsnoop_pkt {
> +	uint32_t	size;		/* Original Length */
> +	uint32_t	len;		/* Included Length */
> +	uint32_t	flags;		/* Packet Flags */
> +	uint32_t	drops;		/* Cumulative Drops */
> +	uint64_t	ts;		/* Timestamp microseconds */
> +	uint8_t		data[0];	/* Packet Data */
> +} __attribute__ ((packed));
> +#define BTSNOOP_PKT_SIZE (sizeof(struct btsnoop_pkt))
> +
> +static const char *path = ".";
> +static const char *prefix = "hci";
> +static bool suffix_date = false;
> +static size_t write_limit = 0;
> +static size_t write_size = 0;
> +
> +static struct btsnoop *btsnoop_file = NULL;
> +
> +static bool create_btsnoop(void)
> +{
> +	static char real_path[FILENAME_MAX];
> +	struct timeval tv;
> +
> +	gettimeofday(&tv, NULL);
> +
> +	if (suffix_date) {
> +		struct tm tm;
> +
> +		localtime_r(&tv.tv_sec, &tm);
> +
> +		snprintf(real_path, FILENAME_MAX,
> +				"%s/%s_%04d-%02d-%02d_%02d:%02d:%02d.btsnoop",
> +				path, prefix, tm.tm_year + 1900, tm.tm_mon + 1,
> +				tm.tm_mday, tm.tm_hour, tm.tm_min, tm.tm_sec);
> +	} else {
> +		static unsigned int cnt = 0;
> +
> +		snprintf(real_path, sizeof(real_path), "%s/%s_%u.btsnoop",
> +							path, prefix, cnt++);
> +	}
> +
> +	btsnoop_file = btsnoop_create(real_path, BTSNOOP_FORMAT_MONITOR);
> +	if(!btsnoop_file)
> +		return false;
> +
> +	write_size = BTSNOOP_HDR_SIZE;
> +
> +	return true;
> +}
> +
> +static void rotate_btsnoop(uint16_t pktlen)
> +{
> +	write_size += BTSNOOP_PKT_SIZE + pktlen;
> +
> +	if (write_size <= write_limit)
> +		return;
> +
> +	btsnoop_unref(btsnoop_file);
> +
> +	if (!create_btsnoop()) {
> +		fprintf(stderr, "Failed to create btsnoop file, exiting.\n");
> +		mainloop_quit();
> +		return;
> +	}
> +
> +	write_size += BTSNOOP_PKT_SIZE + pktlen;
> +}
> +
> +static void data_callback(int fd, uint32_t events, void *user_data)
> +{
> +	uint8_t buf[BTSNOOP_MAX_PACKET_SIZE];
> +	unsigned char control[64];
> +	struct monitor_hdr hdr;
> +	struct msghdr msg;
> +	struct iovec iov[2];
> +
> +	if (events & (EPOLLERR | EPOLLHUP)) {
> +		mainloop_remove_fd(fd);
> +		return;
> +	}
> +
> +	iov[0].iov_base = &hdr;
> +	iov[0].iov_len = sizeof(hdr);
> +	iov[1].iov_base = buf;
> +	iov[1].iov_len = sizeof(buf);
> +
> +	memset(&msg, 0, sizeof(msg));
> +	msg.msg_iov = iov;
> +	msg.msg_iovlen = 2;
> +	msg.msg_control = control;
> +	msg.msg_controllen = sizeof(control);
> +
> +	while (1) {
> +		struct cmsghdr *cmsg;
> +		struct timeval *tv = NULL;
> +		struct timeval ctv;
> +		uint16_t opcode, index, pktlen;
> +		ssize_t len;
> +
> +		len = recvmsg(fd, &msg, MSG_DONTWAIT);
> +		if (len < 0)
> +			break;
> +
> +		if (len < (ssize_t) sizeof(hdr))
> +			break;
> +
> +		for (cmsg = CMSG_FIRSTHDR(&msg); cmsg != NULL;
> +					cmsg = CMSG_NXTHDR(&msg, cmsg)) {
> +			if (cmsg->cmsg_level != SOL_SOCKET)
> +				continue;
> +
> +			if (cmsg->cmsg_type == SCM_TIMESTAMP) {
> +				memcpy(&ctv, CMSG_DATA(cmsg), sizeof(ctv));
> +				tv = &ctv;
> +			}
> +		}
> +
> +		opcode = le16_to_cpu(hdr.opcode);
> +		index  = le16_to_cpu(hdr.index);
> +		pktlen = le16_to_cpu(hdr.len);
> +
> +		if (write_limit)
> +			rotate_btsnoop(pktlen);
> +
> +		btsnoop_write_hci(btsnoop_file, tv, index, opcode, 0, buf,
> +									pktlen);
> +	}
> +}
> +
> +static bool open_monitor_channel(void)
> +{
> +	struct sockaddr_hci addr;
> +	int fd, opt = 1;
> +
> +	fd = socket(AF_BLUETOOTH, SOCK_RAW | SOCK_CLOEXEC, BTPROTO_HCI);
> +	if (fd < 0) {
> +		perror("Failed to open monitor channel");
> +		return false;
> +	}
> +
> +	memset(&addr, 0, sizeof(addr));
> +	addr.hci_family = AF_BLUETOOTH;
> +	addr.hci_dev = HCI_DEV_NONE;
> +	addr.hci_channel = HCI_CHANNEL_MONITOR;
> +
> +	if (bind(fd, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
> +		perror("Failed to bind monitor channel");
> +		close(fd);
> +		return false;
> +	}
> +
> +	if (setsockopt(fd, SOL_SOCKET, SO_TIMESTAMP, &opt, sizeof(opt)) < 0) {
> +		perror("Failed to enable timestamps");
> +		close(fd);
> +		return false;
> +	}
> +
> +	if (setsockopt(fd, SOL_SOCKET, SO_PASSCRED, &opt, sizeof(opt)) < 0) {
> +		perror("Failed to enable credentials");
> +		close(fd);
> +		return false;
> +	}
> +
> +	mainloop_add_fd(fd, EPOLLIN, data_callback, NULL, NULL);
> +
> +	return true;
> +}
> +
> +static void signal_callback(int signum, void *user_data)
> +{
> +	switch (signum) {
> +	case SIGINT:
> +	case SIGTERM:
> +		mainloop_quit();
> +		break;
> +	}
> +}
> +
> +static void usage(void)
> +{
> +	printf("btmon-logger - Bluetooth monitor\n"
> +		"Usage:\n");
> +	printf("\tbtmon-logger [options]\n");
> +	printf("options:\n"
> +		"\t-p, --path <path>      Save traces in specified path\n"
> +		"\t-P, --prefix <name>    Prefix filenames (defaults: \"hci\"\n"
> +		"\t-d, --date             Suffix filenames with date\n"
> +		"\t-l, --limit <limit>    Limit btsnoop file size (rotate)\n"
> +		"\t-v, --version          Show version\n"
> +		"\t-h, --help             Show help options\n");
> +}
> +
> +static const struct option main_options[] = {
> +	{ "path",	required_argument,	NULL, 'p' },
> +	{ "prefix",	required_argument,	NULL, 'P' },
> +	{ "date",	no_argument,		NULL, 'd' },
> +	{ "limit",	required_argument,	NULL, 'l' },
> +	{ "version",	no_argument,		NULL, 'v' },
> +	{ "help",	no_argument,		NULL, 'h' },
> +	{ }
> +};
> +
> +int main(int argc, char *argv[])
> +{
> +	sigset_t mask;
> +	char *endptr;
> +	int ret;
> +
> +	mainloop_init();
> +
> +	while (true) {
> +		int opt;
> +
> +		opt = getopt_long(argc, argv, "p:P:dl:Lvh", main_options,
> +									NULL);
> +		if (opt < 0)
> +			break;
> +
> +		switch (opt) {
> +		case 'p':
> +			path = optarg;
> +			if (strlen(path) > PATH_MAX) {
> +				fprintf(stderr, "Too long path\n");
> +				return EXIT_FAILURE;
> +			}
> +			break;
> +		case 'P':
> +			prefix = optarg;
> +			break;
> +		case 'd':
> +			suffix_date = true;
> +			break;
> +		case 'l':
> +			write_limit = strtoul(optarg, &endptr, 10);
> +
> +			if (write_limit == ULONG_MAX) {
> +				fprintf(stderr, "Invalid limit\n");
> +				return EXIT_FAILURE;
> +			}
> +
> +			if (*endptr != '\0') {
> +				if (*endptr == 'K' || *endptr == 'k') {
> +					write_limit *= 1024;
> +				} else if (*endptr == 'M' || *endptr == 'm') {
> +					write_limit *= 1024 * 1024;
> +				} else {
> +					fprintf(stderr, "Invalid limit\n");
> +					return EXIT_FAILURE;
> +				}
> +			}
> +
> +			/* limit this to reasonable size */
> +			if (write_limit < 4096) {
> +				fprintf(stderr, "Too small limit value\n");
> +				return EXIT_FAILURE;
> +			}
> +			break;
> +		case 'v':
> +			printf("%s\n", VERSION);
> +			return EXIT_SUCCESS;
> +		case 'h':
> +			usage();
> +			return EXIT_SUCCESS;
> +		default:
> +			return EXIT_FAILURE;
> +		}
> +	}
> +
> +	if (argc - optind > 0) {
> +		fprintf(stderr, "Invalid command line parameters\n");
> +		return EXIT_FAILURE;
> +	}
> +
> +	if (!open_monitor_channel() || !create_btsnoop())
> +		return EXIT_FAILURE;
> +
> +	sigemptyset(&mask);
> +	sigaddset(&mask, SIGINT);
> +	sigaddset(&mask, SIGTERM);
> +
> +	mainloop_set_signal(&mask, signal_callback, NULL, NULL);
> +
> +	printf("Bluetooth monitor ver %s\n", VERSION);
> +
> +	ret = mainloop_run();
> +
> +	btsnoop_unref(btsnoop_file);
> +
> +	return ret;
> +}


Any comments on this?

-- 
pozdrawiam
Szymon Janc