busybox/networking/netstat.c
James Byrne 6937487be7 libbb: reduce the overhead of single parameter bb_error_msg() calls
Back in 2007, commit 0c97c9d437 ("'simple' error message functions by
Loic Grenie") introduced bb_simple_perror_msg() to allow for a lower
overhead call to bb_perror_msg() when only a string was being printed
with no parameters. This saves space for some CPU architectures because
it avoids the overhead of a call to a variadic function. However there
has never been a simple version of bb_error_msg(), and since 2007 many
new calls to bb_perror_msg() have been added that only take a single
parameter and so could have been using bb_simple_perror_message().

This changeset introduces 'simple' versions of bb_info_msg(),
bb_error_msg(), bb_error_msg_and_die(), bb_herror_msg() and
bb_herror_msg_and_die(), and replaces all calls that only take a
single parameter, or use something like ("%s", arg), with calls to the
corresponding 'simple' version.

Since it is likely that single parameter calls to the variadic functions
may be accidentally reintroduced in the future a new debugging config
option WARN_SIMPLE_MSG has been introduced. This uses some macro magic
which will cause any such calls to generate a warning, but this is
turned off by default to avoid use of the unpleasant macros in normal
circumstances.

This is a large changeset due to the number of calls that have been
replaced. The only files that contain changes other than simple
substitution of function calls are libbb.h, libbb/herror_msg.c,
libbb/verror_msg.c and libbb/xfuncs_printf.c. In miscutils/devfsd.c,
networking/udhcp/common.h and util-linux/mdev.c additonal macros have
been added for logging so that single parameter and multiple parameter
logging variants exist.

The amount of space saved varies considerably by architecture, and was
found to be as follows (for 'defconfig' using GCC 7.4):

Arm:     -92 bytes
MIPS:    -52 bytes
PPC:   -1836 bytes
x86_64: -938 bytes

Note that for the MIPS architecture only an exception had to be made
disabling the 'simple' calls for 'udhcp' (in networking/udhcp/common.h)
because it made these files larger on MIPS.

Signed-off-by: James Byrne <james.byrne@origamienergy.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2019-07-02 11:35:03 +02:00

776 lines
20 KiB
C

/* vi: set sw=4 ts=4: */
/*
* Mini netstat implementation(s) for busybox
* based in part on the netstat implementation from net-tools.
*
* Copyright (C) 2002 by Bart Visscher <magick@linux-fan.com>
*
* 2002-04-20
* IPV6 support added by Bart Visscher <magick@linux-fan.com>
*
* 2008-07-10
* optional '-p' flag support ported from net-tools by G. Somlo <somlo@cmu.edu>
*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
//config:config NETSTAT
//config: bool "netstat (10 kb)"
//config: default y
//config: select PLATFORM_LINUX
//config: help
//config: netstat prints information about the Linux networking subsystem.
//config:
//config:config FEATURE_NETSTAT_WIDE
//config: bool "Enable wide output"
//config: default y
//config: depends on NETSTAT
//config: help
//config: Add support for wide columns. Useful when displaying IPv6 addresses
//config: (-W option).
//config:
//config:config FEATURE_NETSTAT_PRG
//config: bool "Enable PID/Program name output"
//config: default y
//config: depends on NETSTAT
//config: help
//config: Add support for -p flag to print out PID and program name.
//config: +700 bytes of code.
//applet:IF_NETSTAT(APPLET(netstat, BB_DIR_BIN, BB_SUID_DROP))
//kbuild:lib-$(CONFIG_NETSTAT) += netstat.o
#include "libbb.h"
#include "inet_common.h"
//usage:#define netstat_trivial_usage
//usage: "[-"IF_ROUTE("r")"al] [-tuwx] [-en"IF_FEATURE_NETSTAT_WIDE("W")IF_FEATURE_NETSTAT_PRG("p")"]"
//usage:#define netstat_full_usage "\n\n"
//usage: "Display networking information\n"
//usage: IF_ROUTE(
//usage: "\n -r Routing table"
//usage: )
//usage: "\n -a All sockets"
//usage: "\n -l Listening sockets"
//usage: "\n Else: connected sockets"
//usage: "\n -t TCP sockets"
//usage: "\n -u UDP sockets"
//usage: "\n -w Raw sockets"
//usage: "\n -x Unix sockets"
//usage: "\n Else: all socket types"
//usage: "\n -e Other/more information"
//usage: "\n -n Don't resolve names"
//usage: IF_FEATURE_NETSTAT_WIDE(
//usage: "\n -W Wide display"
//usage: )
//usage: IF_FEATURE_NETSTAT_PRG(
//usage: "\n -p Show PID/program name for sockets"
//usage: )
#define NETSTAT_OPTS "laentuwx" \
IF_ROUTE( "r") \
IF_FEATURE_NETSTAT_WIDE("W") \
IF_FEATURE_NETSTAT_PRG( "p")
enum {
OPT_sock_listen = 1 << 0, // l
OPT_sock_all = 1 << 1, // a
OPT_extended = 1 << 2, // e
OPT_noresolve = 1 << 3, // n
OPT_sock_tcp = 1 << 4, // t
OPT_sock_udp = 1 << 5, // u
OPT_sock_raw = 1 << 6, // w
OPT_sock_unix = 1 << 7, // x
OPTBIT_x = 7,
IF_ROUTE( OPTBIT_ROUTE,)
IF_FEATURE_NETSTAT_WIDE(OPTBIT_WIDE ,)
IF_FEATURE_NETSTAT_PRG( OPTBIT_PRG ,)
OPT_route = IF_ROUTE( (1 << OPTBIT_ROUTE)) + 0, // r
OPT_wide = IF_FEATURE_NETSTAT_WIDE((1 << OPTBIT_WIDE )) + 0, // W
OPT_prg = IF_FEATURE_NETSTAT_PRG( (1 << OPTBIT_PRG )) + 0, // p
};
#define NETSTAT_CONNECTED 0x01
#define NETSTAT_LISTENING 0x02
#define NETSTAT_NUMERIC 0x04
/* Must match getopt32 option string */
#define NETSTAT_TCP 0x10
#define NETSTAT_UDP 0x20
#define NETSTAT_RAW 0x40
#define NETSTAT_UNIX 0x80
#define NETSTAT_ALLPROTO (NETSTAT_TCP|NETSTAT_UDP|NETSTAT_RAW|NETSTAT_UNIX)
enum {
TCP_ESTABLISHED = 1,
TCP_SYN_SENT,
TCP_SYN_RECV,
TCP_FIN_WAIT1,
TCP_FIN_WAIT2,
TCP_TIME_WAIT,
TCP_CLOSE,
TCP_CLOSE_WAIT,
TCP_LAST_ACK,
TCP_LISTEN,
TCP_CLOSING, /* now a valid state */
};
static const char *const tcp_state[] = {
"",
"ESTABLISHED",
"SYN_SENT",
"SYN_RECV",
"FIN_WAIT1",
"FIN_WAIT2",
"TIME_WAIT",
"CLOSE",
"CLOSE_WAIT",
"LAST_ACK",
"LISTEN",
"CLOSING"
};
typedef enum {
SS_FREE = 0, /* not allocated */
SS_UNCONNECTED, /* unconnected to any socket */
SS_CONNECTING, /* in process of connecting */
SS_CONNECTED, /* connected to socket */
SS_DISCONNECTING /* in process of disconnecting */
} socket_state;
#define SO_ACCEPTCON (1<<16) /* performed a listen */
#define SO_WAITDATA (1<<17) /* wait data to read */
#define SO_NOSPACE (1<<18) /* no space to write */
#define ADDR_NORMAL_WIDTH 23
/* When there are IPv6 connections the IPv6 addresses will be
* truncated to none-recognition. The '-W' option makes the
* address columns wide enough to accommodate for longest possible
* IPv6 addresses, i.e. addresses of the form
* xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:ddd.ddd.ddd.ddd
*/
#define ADDR_WIDE 51 /* INET6_ADDRSTRLEN + 5 for the port number */
#if ENABLE_FEATURE_NETSTAT_WIDE
# define FMT_NET_CONN_DATA "%s %6lu %6lu %-*s %-*s %-12s"
# define FMT_NET_CONN_HEADER "\nProto Recv-Q Send-Q %-*s %-*s State %s\n"
#else
# define FMT_NET_CONN_DATA "%s %6lu %6lu %-23s %-23s %-12s"
# define FMT_NET_CONN_HEADER "\nProto Recv-Q Send-Q %-23s %-23s State %s\n"
#endif
#define PROGNAME_WIDTH 20
#define PROGNAME_WIDTH_STR "20"
/* PROGNAME_WIDTH chars: 12345678901234567890 */
#define PROGNAME_BANNER "PID/Program name "
struct prg_node {
struct prg_node *next;
long inode;
char name[PROGNAME_WIDTH];
};
#define PRG_HASH_SIZE 211
struct globals {
smallint flags;
#if ENABLE_FEATURE_NETSTAT_PRG
smallint prg_cache_loaded;
struct prg_node *prg_hash[PRG_HASH_SIZE];
#endif
#if ENABLE_FEATURE_NETSTAT_PRG
const char *progname_banner;
#endif
#if ENABLE_FEATURE_NETSTAT_WIDE
unsigned addr_width;
#endif
};
#define G (*ptr_to_globals)
#define flags (G.flags )
#define prg_cache_loaded (G.prg_cache_loaded)
#define prg_hash (G.prg_hash )
#if ENABLE_FEATURE_NETSTAT_PRG
# define progname_banner (G.progname_banner )
#else
# define progname_banner ""
#endif
#define INIT_G() do { \
SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
flags = NETSTAT_CONNECTED | NETSTAT_ALLPROTO; \
} while (0)
#if ENABLE_FEATURE_NETSTAT_PRG
/* Deliberately truncating long to unsigned *int* */
#define PRG_HASHIT(x) ((unsigned)(x) % PRG_HASH_SIZE)
static void prg_cache_add(long inode, char *name)
{
unsigned hi = PRG_HASHIT(inode);
struct prg_node **pnp, *pn;
prg_cache_loaded = 2;
for (pnp = prg_hash + hi; (pn = *pnp) != NULL; pnp = &pn->next) {
if (pn->inode == inode) {
/* Some warning should be appropriate here
* as we got multiple processes for one i-node */
return;
}
}
*pnp = xzalloc(sizeof(struct prg_node));
pn = *pnp;
pn->inode = inode;
safe_strncpy(pn->name, name, PROGNAME_WIDTH);
}
static const char *prg_cache_get(long inode)
{
unsigned hi = PRG_HASHIT(inode);
struct prg_node *pn;
for (pn = prg_hash[hi]; pn; pn = pn->next)
if (pn->inode == inode)
return pn->name;
return "-";
}
#if ENABLE_FEATURE_CLEAN_UP
static void prg_cache_clear(void)
{
struct prg_node **pnp, *pn;
for (pnp = prg_hash; pnp < prg_hash + PRG_HASH_SIZE; pnp++) {
while ((pn = *pnp) != NULL) {
*pnp = pn->next;
free(pn);
}
}
}
#else
#define prg_cache_clear() ((void)0)
#endif
static long extract_socket_inode(const char *lname)
{
long inode = -1;
if (is_prefixed_with(lname, "socket:[")) {
/* "socket:[12345]", extract the "12345" as inode */
inode = bb_strtoul(lname + sizeof("socket:[")-1, (char**)&lname, 0);
if (*lname != ']')
inode = -1;
} else if (is_prefixed_with(lname, "[0000]:")) {
/* "[0000]:12345", extract the "12345" as inode */
inode = bb_strtoul(lname + sizeof("[0000]:")-1, NULL, 0);
if (errno) /* not NUL terminated? */
inode = -1;
}
#if 0 /* bb_strtol returns all-ones bit pattern on ERANGE anyway */
if (errno == ERANGE)
inode = -1;
#endif
return inode;
}
static int FAST_FUNC add_to_prg_cache_if_socket(const char *fileName,
struct stat *statbuf UNUSED_PARAM,
void *pid_slash_progname,
int depth UNUSED_PARAM)
{
char *linkname;
long inode;
linkname = xmalloc_readlink(fileName);
if (linkname != NULL) {
inode = extract_socket_inode(linkname);
free(linkname);
if (inode >= 0)
prg_cache_add(inode, (char *)pid_slash_progname);
}
return TRUE;
}
static int FAST_FUNC dir_act(const char *fileName,
struct stat *statbuf UNUSED_PARAM,
void *userData UNUSED_PARAM,
int depth)
{
const char *pid;
char *pid_slash_progname;
char proc_pid_fname[sizeof("/proc/%u/cmdline") + sizeof(long)*3];
char cmdline_buf[512];
int n, len;
if (depth == 0) /* "/proc" itself */
return TRUE; /* continue looking one level below /proc */
pid = fileName + sizeof("/proc/")-1; /* point after "/proc/" */
if (!isdigit(pid[0])) /* skip /proc entries which aren't processes */
return SKIP;
len = snprintf(proc_pid_fname, sizeof(proc_pid_fname), "%s/cmdline", fileName);
n = open_read_close(proc_pid_fname, cmdline_buf, sizeof(cmdline_buf) - 1);
if (n < 0)
return FALSE;
cmdline_buf[n] = '\0';
/* go through all files in /proc/PID/fd and check whether they are sockets */
strcpy(proc_pid_fname + len - (sizeof("cmdline")-1), "fd");
pid_slash_progname = concat_path_file(pid, bb_basename(cmdline_buf)); /* "PID/argv0" */
n = recursive_action(proc_pid_fname,
ACTION_RECURSE | ACTION_QUIET,
add_to_prg_cache_if_socket,
NULL,
(void *)pid_slash_progname,
0);
free(pid_slash_progname);
if (!n)
return FALSE; /* signal permissions error to caller */
return SKIP; /* caller should not recurse further into this dir */
}
static void prg_cache_load(void)
{
int load_ok;
prg_cache_loaded = 1;
load_ok = recursive_action("/proc", ACTION_RECURSE | ACTION_QUIET,
NULL, dir_act, NULL, 0);
if (load_ok)
return;
if (prg_cache_loaded == 1)
bb_simple_error_msg("can't scan /proc - are you root?");
else
bb_simple_error_msg("showing only processes with your user ID");
}
#else
#define prg_cache_clear() ((void)0)
#endif //ENABLE_FEATURE_NETSTAT_PRG
#if ENABLE_FEATURE_IPV6
static void build_ipv6_addr(char* local_addr, struct sockaddr_in6* localaddr)
{
char addr6[INET6_ADDRSTRLEN];
struct in6_addr in6;
sscanf(local_addr, "%08X%08X%08X%08X",
&in6.s6_addr32[0], &in6.s6_addr32[1],
&in6.s6_addr32[2], &in6.s6_addr32[3]);
inet_ntop(AF_INET6, &in6, addr6, sizeof(addr6));
inet_pton(AF_INET6, addr6, &localaddr->sin6_addr);
localaddr->sin6_family = AF_INET6;
}
#endif
static void build_ipv4_addr(char* local_addr, struct sockaddr_in* localaddr)
{
sscanf(local_addr, "%X", &localaddr->sin_addr.s_addr);
localaddr->sin_family = AF_INET;
}
static const char *get_sname(int port, const char *proto, int numeric)
{
if (!port)
return "*";
if (!numeric) {
struct servent *se = getservbyport(port, proto);
if (se)
return se->s_name;
}
/* hummm, we may return static buffer here!! */
return itoa(ntohs(port));
}
static char *ip_port_str(struct sockaddr *addr, int port, const char *proto, int numeric)
{
char *host, *host_port;
/* Code which used "*" for INADDR_ANY is removed: it's ambiguous
* in IPv6, while "0.0.0.0" is not. */
host = NULL;
if (!numeric)
host = xmalloc_sockaddr2host_noport(addr);
if (!host)
host = xmalloc_sockaddr2dotted_noport(addr);
host_port = xasprintf("%s:%s", host, get_sname(htons(port), proto, numeric));
free(host);
return host_port;
}
struct inet_params {
int local_port, rem_port, state, uid;
union {
struct sockaddr sa;
struct sockaddr_in sin;
#if ENABLE_FEATURE_IPV6
struct sockaddr_in6 sin6;
#endif
} localaddr, remaddr;
unsigned long rxq, txq, inode;
};
static int scan_inet_proc_line(struct inet_params *param, char *line)
{
int num;
/* IPv6 /proc files use 32-char hex representation
* of IPv6 address, followed by :PORT_IN_HEX
*/
char local_addr[33], rem_addr[33]; /* 32 + 1 for NUL */
num = sscanf(line,
"%*d: %32[0-9A-Fa-f]:%X "
"%32[0-9A-Fa-f]:%X %X "
"%lX:%lX %*X:%*X "
"%*X %d %*d %lu ",
local_addr, &param->local_port,
rem_addr, &param->rem_port, &param->state,
&param->txq, &param->rxq,
&param->uid, &param->inode);
if (num < 9) {
return 1; /* error */
}
if (strlen(local_addr) > 8) {
#if ENABLE_FEATURE_IPV6
build_ipv6_addr(local_addr, &param->localaddr.sin6);
build_ipv6_addr(rem_addr, &param->remaddr.sin6);
#endif
} else {
build_ipv4_addr(local_addr, &param->localaddr.sin);
build_ipv4_addr(rem_addr, &param->remaddr.sin);
}
return 0;
}
static void print_inet_line(struct inet_params *param,
const char *state_str, const char *proto, int is_connected)
{
if ((is_connected && (flags & NETSTAT_CONNECTED))
|| (!is_connected && (flags & NETSTAT_LISTENING))
) {
char *l = ip_port_str(
&param->localaddr.sa, param->local_port,
proto, flags & NETSTAT_NUMERIC);
char *r = ip_port_str(
&param->remaddr.sa, param->rem_port,
proto, flags & NETSTAT_NUMERIC);
printf(FMT_NET_CONN_DATA,
proto, param->rxq, param->txq,
IF_FEATURE_NETSTAT_WIDE(G.addr_width,) l,
IF_FEATURE_NETSTAT_WIDE(G.addr_width,) r,
state_str);
#if ENABLE_FEATURE_NETSTAT_PRG
if (option_mask32 & OPT_prg)
printf("%."PROGNAME_WIDTH_STR"s", prg_cache_get(param->inode));
#endif
bb_putchar('\n');
free(l);
free(r);
}
}
static int FAST_FUNC tcp_do_one(char *line)
{
struct inet_params param;
memset(&param, 0, sizeof(param));
if (scan_inet_proc_line(&param, line))
return 1;
print_inet_line(&param, tcp_state[param.state], "tcp", param.rem_port);
return 0;
}
#if ENABLE_FEATURE_IPV6
# define NOT_NULL_ADDR(A) ( \
( (A.sa.sa_family == AF_INET6) \
&& (A.sin6.sin6_addr.s6_addr32[0] | A.sin6.sin6_addr.s6_addr32[1] | \
A.sin6.sin6_addr.s6_addr32[2] | A.sin6.sin6_addr.s6_addr32[3]) \
) || ( \
(A.sa.sa_family == AF_INET) \
&& A.sin.sin_addr.s_addr != 0 \
) \
)
#else
# define NOT_NULL_ADDR(A) (A.sin.sin_addr.s_addr)
#endif
static int FAST_FUNC udp_do_one(char *line)
{
int have_remaddr;
const char *state_str;
struct inet_params param;
memset(&param, 0, sizeof(param)); /* otherwise we display garbage IPv6 scope_ids */
if (scan_inet_proc_line(&param, line))
return 1;
state_str = "UNKNOWN";
switch (param.state) {
case TCP_ESTABLISHED:
state_str = "ESTABLISHED";
break;
case TCP_CLOSE:
state_str = "";
break;
}
have_remaddr = NOT_NULL_ADDR(param.remaddr);
print_inet_line(&param, state_str, "udp", have_remaddr);
return 0;
}
static int FAST_FUNC raw_do_one(char *line)
{
int have_remaddr;
struct inet_params param;
if (scan_inet_proc_line(&param, line))
return 1;
have_remaddr = NOT_NULL_ADDR(param.remaddr);
print_inet_line(&param, itoa(param.state), "raw", have_remaddr);
return 0;
}
static int FAST_FUNC unix_do_one(char *line)
{
unsigned long refcnt, proto, unix_flags;
unsigned long inode;
int type, state;
int num, path_ofs;
const char *ss_proto, *ss_state, *ss_type;
char ss_flags[32];
/* 2.6.15 may report lines like "... @/tmp/fam-user-^@^@^@^@^@^@^@..."
* Other users report long lines filled by NUL bytes.
* (those ^@ are NUL bytes too). We see them as empty lines. */
if (!line[0])
return 0;
path_ofs = 0; /* paranoia */
num = sscanf(line, "%*p: %lX %lX %lX %X %X %lu %n",
&refcnt, &proto, &unix_flags, &type, &state, &inode, &path_ofs);
if (num < 6) {
return 1; /* error */
}
if ((flags & (NETSTAT_LISTENING|NETSTAT_CONNECTED)) != (NETSTAT_LISTENING|NETSTAT_CONNECTED)) {
if ((state == SS_UNCONNECTED) && (unix_flags & SO_ACCEPTCON)) {
if (!(flags & NETSTAT_LISTENING))
return 0;
} else {
if (!(flags & NETSTAT_CONNECTED))
return 0;
}
}
switch (proto) {
case 0:
ss_proto = "unix";
break;
default:
ss_proto = "??";
}
switch (type) {
case SOCK_STREAM:
ss_type = "STREAM";
break;
case SOCK_DGRAM:
ss_type = "DGRAM";
break;
case SOCK_RAW:
ss_type = "RAW";
break;
case SOCK_RDM:
ss_type = "RDM";
break;
case SOCK_SEQPACKET:
ss_type = "SEQPACKET";
break;
default:
ss_type = "UNKNOWN";
}
switch (state) {
case SS_FREE:
ss_state = "FREE";
break;
case SS_UNCONNECTED:
/*
* Unconnected sockets may be listening
* for something.
*/
if (unix_flags & SO_ACCEPTCON) {
ss_state = "LISTENING";
} else {
ss_state = "";
}
break;
case SS_CONNECTING:
ss_state = "CONNECTING";
break;
case SS_CONNECTED:
ss_state = "CONNECTED";
break;
case SS_DISCONNECTING:
ss_state = "DISCONNECTING";
break;
default:
ss_state = "UNKNOWN";
}
strcpy(ss_flags, "[ ");
if (unix_flags & SO_ACCEPTCON)
strcat(ss_flags, "ACC ");
if (unix_flags & SO_WAITDATA)
strcat(ss_flags, "W ");
if (unix_flags & SO_NOSPACE)
strcat(ss_flags, "N ");
strcat(ss_flags, "]");
printf("%-5s %-6lu %-11s %-10s %-13s %6lu ",
ss_proto, refcnt, ss_flags, ss_type, ss_state, inode
);
#if ENABLE_FEATURE_NETSTAT_PRG
if (option_mask32 & OPT_prg)
printf("%-"PROGNAME_WIDTH_STR"s", prg_cache_get(inode));
#endif
/* TODO: currently we stop at first NUL byte. Is it a problem? */
line += path_ofs;
chomp(line);
while (*line)
fputc_printable(*line++, stdout);
bb_putchar('\n');
return 0;
}
static void do_info(const char *file, int FAST_FUNC (*proc)(char *))
{
int lnr;
FILE *procinfo;
char *buffer;
/* _stdin is just to save "r" param */
procinfo = fopen_or_warn_stdin(file);
if (procinfo == NULL) {
return;
}
lnr = 0;
/* Why xmalloc_fgets_str? because it doesn't stop on NULs */
while ((buffer = xmalloc_fgets_str(procinfo, "\n")) != NULL) {
/* line 0 is skipped */
if (lnr && proc(buffer))
bb_error_msg("%s: bogus data on line %d", file, lnr + 1);
lnr++;
free(buffer);
}
fclose(procinfo);
}
int netstat_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int netstat_main(int argc UNUSED_PARAM, char **argv)
{
unsigned opt;
INIT_G();
/* Option string must match NETSTAT_xxx constants */
opt = getopt32(argv, NETSTAT_OPTS);
if (opt & OPT_sock_listen) { // -l
flags &= ~NETSTAT_CONNECTED;
flags |= NETSTAT_LISTENING;
}
if (opt & OPT_sock_all) flags |= NETSTAT_LISTENING | NETSTAT_CONNECTED; // -a
//if (opt & OPT_extended) // -e
if (opt & OPT_noresolve) flags |= NETSTAT_NUMERIC; // -n
//if (opt & OPT_sock_tcp) // -t: NETSTAT_TCP
//if (opt & OPT_sock_udp) // -u: NETSTAT_UDP
//if (opt & OPT_sock_raw) // -w: NETSTAT_RAW
//if (opt & OPT_sock_unix) // -x: NETSTAT_UNIX
#if ENABLE_ROUTE
if (opt & OPT_route) { // -r
bb_displayroutes(flags & NETSTAT_NUMERIC, !(opt & OPT_extended));
return 0;
}
#endif
#if ENABLE_FEATURE_NETSTAT_WIDE
G.addr_width = ADDR_NORMAL_WIDTH;
if (opt & OPT_wide) { // -W
G.addr_width = ADDR_WIDE;
}
#endif
#if ENABLE_FEATURE_NETSTAT_PRG
progname_banner = "";
if (opt & OPT_prg) { // -p
progname_banner = PROGNAME_BANNER;
prg_cache_load();
}
#endif
opt &= NETSTAT_ALLPROTO;
if (opt) {
flags &= ~NETSTAT_ALLPROTO;
flags |= opt;
}
if (flags & (NETSTAT_TCP|NETSTAT_UDP|NETSTAT_RAW)) {
printf("Active Internet connections "); /* xxx */
if ((flags & (NETSTAT_LISTENING|NETSTAT_CONNECTED)) == (NETSTAT_LISTENING|NETSTAT_CONNECTED))
printf("(servers and established)");
else if (flags & NETSTAT_LISTENING)
printf("(only servers)");
else
printf("(w/o servers)");
printf(FMT_NET_CONN_HEADER,
IF_FEATURE_NETSTAT_WIDE(G.addr_width,) "Local Address",
IF_FEATURE_NETSTAT_WIDE(G.addr_width,) "Foreign Address",
progname_banner
);
}
if (flags & NETSTAT_TCP) {
do_info("/proc/net/tcp", tcp_do_one);
#if ENABLE_FEATURE_IPV6
do_info("/proc/net/tcp6", tcp_do_one);
#endif
}
if (flags & NETSTAT_UDP) {
do_info("/proc/net/udp", udp_do_one);
#if ENABLE_FEATURE_IPV6
do_info("/proc/net/udp6", udp_do_one);
#endif
}
if (flags & NETSTAT_RAW) {
do_info("/proc/net/raw", raw_do_one);
#if ENABLE_FEATURE_IPV6
do_info("/proc/net/raw6", raw_do_one);
#endif
}
if (flags & NETSTAT_UNIX) {
printf("Active UNIX domain sockets ");
if ((flags & (NETSTAT_LISTENING|NETSTAT_CONNECTED)) == (NETSTAT_LISTENING|NETSTAT_CONNECTED))
printf("(servers and established)");
else if (flags & NETSTAT_LISTENING)
printf("(only servers)");
else
printf("(w/o servers)");
printf("\nProto RefCnt Flags Type State I-Node %sPath\n", progname_banner);
do_info("/proc/net/unix", unix_do_one);
}
prg_cache_clear();
return 0;
}