d/freebsd-skq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Allow TCP connections to be filtered by stack and state.

Browse Source 
Choose the command line options to be consistent with the ones of
sockstat.

Sponsored by:	Netflix, Inc.
This commit is contained in:
tuexen 2017-09-12 13:39:44 +00:00
parent 56b9f343a0
commit f7025df466
2 changed files with 110 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

77
usr.sbin/tcpdrop/tcpdrop.8
View File

@ -17,7 +17,7 @@
.\"
.\" $FreeBSD$
.\"
.Dd January 30, 2013
.Dd September 12, 2017
.Dt TCPDROP 8
.Os
.Sh NAME
@ -32,6 +32,16 @@
.Nm tcpdrop
.Op Fl l
.Fl a
.Nm tcpdrop
.Op Fl l
.Fl S Ar stack
.Nm tcpdrop
.Op Fl l
.Fl s Ar state
.Nm tcpdrop
.Op Fl l
.Fl S Ar stack
.Fl s Ar state
.Sh DESCRIPTION
The
.Nm
@ -41,15 +51,49 @@ If
.Fl a
is specified then
.Nm
will attempt to drop all active connections.
The
.Fl l
flag may be given to list the tcpdrop invocation to drop all active
connections one at a time.
will attempt to drop all TCP connections.
.Pp
If
.Fl a
is not specified then only the connection between the given local
.Fl S Ar stack
is specified then
.Nm
will attempt to drop all connections using the TCP stack
.Ar stack .
.Pp
If
.Fl s Ar state
is specified then
.Nm
will attempt to drop all TCP connections being in the state
.Ar state .
.Ar state
is one of
.Dv SYN_SENT ,
.Dv SYN_RCVD ,
.Dv ESTABLISHED ,
.Dv CLOSE_WAIT ,
.Dv FIN_WAIT_1 ,
.Dv CLOSING ,
.Dv LAST_ACK ,
.Dv FIN_WAIT_2 , or
.Dv TIME_WAIT .
.Pp
The
.Fl l
flag may be given in addition to the
.Fl a ,
.Fl S ,
or
.Fl s
options to list the tcpdrop invocation to drop all corresponding TCP
connections one at a time.
.Pp
If none of the
.Fl a ,
.Fl S ,
or
.Fl s
options are specified then only the connection between the given local
address
.Ar local-address ,
port
@ -89,6 +133,23 @@ port 22, the port used by
.Bd -literal -offset indent
# tcpdrop -l -a | grep -vw 22 | sh
.Ed
.Pp
The following command will drop all connections using the TCP stack
fastack:
.Bd -literal -offset indent
# tcpdrop -S fastack
.Ed
.Pp
To drop all TCP connections in the LAST_ACK state use:
.Bd -literal -offset indent
# tcpdrop -s LAST_ACK
.Ed
.Pp
To drop all TCP connections using the TCP stack fastack and being in the
LAST_ACK state use:
.Bd -literal -offset indent
# tcpdrop -S fastack -s LAST_ACK
.Ed
.Sh SEE ALSO
.Xr netstat 1 ,
.Xr sockstat 1

49
usr.sbin/tcpdrop/tcpdrop.c
View File

@ -54,7 +54,7 @@ static char *findport(const char *);
static struct xinpgen *getxpcblist(const char *);
static void sockinfo(const struct sockaddr *, struct host_service *);
static bool tcpdrop(const struct sockaddr *, const struct sockaddr *);
static bool tcpdropall(void);
static bool tcpdropall(const char *, int);
static bool tcpdropbyname(const char *, const char *, const char *,
const char *);
static bool tcpdropconn(const struct in_conninfo *);
@ -66,13 +66,17 @@ static void usage(void);
int
main(int argc, char *argv[])
{
char stack[TCP_FUNCTION_NAME_LEN_MAX];
char *lport, *fport;
bool dropall;
int ch;
bool dropall, dropallstack;
int ch, state;
dropall = false;
dropallstack = false;
memset(stack, 0, TCP_FUNCTION_NAME_LEN_MAX);
state = -1;
while ((ch = getopt(argc, argv, "al")) != -1) {
while ((ch = getopt(argc, argv, "alS:s:")) != -1) {
switch (ch) {
case 'a':
dropall = true;
@ -80,6 +84,17 @@ main(int argc, char *argv[])
case 'l':
tcpdrop_list_commands = true;
break;
case 'S':
dropallstack = true;
strncpy(stack, optarg, TCP_FUNCTION_NAME_LEN_MAX);
break;
case 's':
dropallstack = true;
for (state = 0; state < TCP_NSTATES; state++) {
if (strcmp(tcpstates[state], optarg) == 0)
break;
}
break;
default:
usage();
}
@ -87,10 +102,16 @@ main(int argc, char *argv[])
argc -= optind;
argv += optind;
if (dropall) {
if (state == TCP_NSTATES ||
state == TCPS_CLOSED ||
state == TCPS_LISTEN)
usage();
if (dropall && dropallstack)
usage();
if (dropall || dropallstack) {
if (argc != 0)
usage();
if (!tcpdropall())
if (!tcpdropall(stack, state))
exit(1);
exit(0);
}
@ -202,7 +223,7 @@ tcpdrop(const struct sockaddr *lsa, const struct sockaddr *fsa)
}
static bool
tcpdropall(void)
tcpdropall(const char *stack, int state)
{
struct xinpgen *head, *xinp;
struct xtcpcb *xtp;
@ -234,6 +255,15 @@ tcpdropall(void)
if (xtp->t_state == TCPS_LISTEN)
continue;
/* If requested, skip sockets not having the requested state. */
if ((state != -1) && (xtp->t_state != state))
continue;
/* If requested, skip sockets not having the requested stack. */
if (strnlen(stack, TCP_FUNCTION_NAME_LEN_MAX) > 0 &&
strncmp(xtp->xt_stack, stack, TCP_FUNCTION_NAME_LEN_MAX))
continue;
if (!tcpdropconn(&xip->inp_inc))
ok = false;
}
@ -348,6 +378,9 @@ usage(void)
"usage: tcpdrop local-address local-port foreign-address foreign-port\n"
" tcpdrop local-address:local-port foreign-address:foreign-port\n"
" tcpdrop local-address.local-port foreign-address.foreign-port\n"
" tcpdrop [-l] -a\n");
" tcpdrop [-l] -a\n"
" tcpdrop [-l] -S stack\n"
" tcpdrop [-l] -s state\n"
" tcpdrop [-l] -S stack -s state\n");
exit(1);
}