Commit | Line | Data |
---|---|---|
a0d0e21e LW |
1 | package Net::Ping; |
2 | ||
b124990b | 3 | require 5.002; |
a0d0e21e LW |
4 | require Exporter; |
5 | ||
a3b93737 | 6 | use strict; |
b124990b | 7 | use vars qw(@ISA @EXPORT $VERSION |
9539e94f JH |
8 | $def_timeout $def_proto $def_factor |
9 | $max_datasize $pingstring $hires $source_verify $syn_forking); | |
f569508e | 10 | use Fcntl qw( F_GETFL F_SETFL O_NONBLOCK ); |
eb194dd9 | 11 | use Socket qw( SOCK_DGRAM SOCK_STREAM SOCK_RAW PF_INET SOL_SOCKET SO_ERROR |
e82f584b | 12 | inet_aton inet_ntoa sockaddr_in ); |
eb194dd9 | 13 | use POSIX qw( ENOTCONN ECONNREFUSED ECONNRESET EINPROGRESS EWOULDBLOCK EAGAIN WNOHANG ); |
f569508e | 14 | use FileHandle; |
a3b93737 | 15 | use Carp; |
a79c1648 | 16 | |
a0d0e21e | 17 | @ISA = qw(Exporter); |
a3b93737 | 18 | @EXPORT = qw(pingecho); |
5d6b07c5 | 19 | $VERSION = "2.35"; |
03550e9d JH |
20 | |
21 | sub SOL_IP { 0; }; | |
22 | sub IP_TOS { 1; }; | |
a0d0e21e | 23 | |
a3b93737 | 24 | # Constants |
a0d0e21e | 25 | |
a3b93737 | 26 | $def_timeout = 5; # Default timeout to wait for a reply |
a5a165b1 | 27 | $def_proto = "tcp"; # Default protocol to use for pinging |
9539e94f | 28 | $def_factor = 1.2; # Default exponential backoff rate. |
a3b93737 | 29 | $max_datasize = 1024; # Maximum data bytes in a packet |
b124990b JH |
30 | # The data we exchange with the server for the stream protocol |
31 | $pingstring = "pingschwingping!\n"; | |
5d20095f | 32 | $source_verify = 1; # Default is to verify source endpoint |
f569508e | 33 | $syn_forking = 0; |
a0d0e21e | 34 | |
ef73e1db JH |
35 | if ($^O =~ /Win32/i) { |
36 | # Hack to avoid this Win32 spewage: | |
37 | # Your vendor has not defined POSIX macro ECONNREFUSED | |
5d6b07c5 NC |
38 | my @pairs = (ECONNREFUSED => 10061, # "Unknown Error" Special Win32 Response? |
39 | ENOTCONN => 10057, | |
40 | ECONNRESET => 10054, | |
41 | EINPROGRESS => 10036, | |
42 | EWOULDBLOCK => 10035, | |
43 | ); | |
44 | while (my $name = shift @pairs) { | |
45 | my $value = shift @pairs; | |
46 | # When defined, these all are non-zero | |
47 | unless (eval $name) { | |
48 | no strict 'refs'; | |
49 | *{$name} = defined prototype \&{$name} ? sub () {$value} : sub {$value}; | |
50 | } | |
51 | } | |
eb194dd9 | 52 | # $syn_forking = 1; # XXX possibly useful in < Win2K ? |
ef73e1db JH |
53 | }; |
54 | ||
f569508e HS |
55 | # h2ph "asm/socket.h" |
56 | # require "asm/socket.ph"; | |
57 | sub SO_BINDTODEVICE {25;} | |
58 | ||
a3b93737 RM |
59 | # Description: The pingecho() subroutine is provided for backward |
60 | # compatibility with the original Net::Ping. It accepts a host | |
61 | # name/IP and an optional timeout in seconds. Create a tcp ping | |
62 | # object and try pinging the host. The result of the ping is returned. | |
a0d0e21e | 63 | |
a3b93737 RM |
64 | sub pingecho |
65 | { | |
e82f584b JH |
66 | my ($host, # Name or IP number of host to ping |
67 | $timeout # Optional timeout in seconds | |
68 | ) = @_; | |
69 | my ($p); # A ping object | |
a0d0e21e | 70 | |
e82f584b JH |
71 | $p = Net::Ping->new("tcp", $timeout); |
72 | $p->ping($host); # Going out of scope closes the connection | |
a3b93737 | 73 | } |
a0d0e21e | 74 | |
a3b93737 RM |
75 | # Description: The new() method creates a new ping object. Optional |
76 | # parameters may be specified for the protocol to use, the timeout in | |
77 | # seconds and the size in bytes of additional data which should be | |
78 | # included in the packet. | |
79 | # After the optional parameters are checked, the data is constructed | |
80 | # and a socket is opened if appropriate. The object is returned. | |
81 | ||
82 | sub new | |
83 | { | |
e82f584b JH |
84 | my ($this, |
85 | $proto, # Optional protocol to use for pinging | |
86 | $timeout, # Optional timeout in seconds | |
f569508e HS |
87 | $data_size, # Optional additional bytes of data |
88 | $device, # Optional device to use | |
03550e9d | 89 | $tos, # Optional ToS to set |
e82f584b JH |
90 | ) = @_; |
91 | my $class = ref($this) || $this; | |
92 | my $self = {}; | |
93 | my ($cnt, # Count through data bytes | |
94 | $min_datasize # Minimum data bytes required | |
95 | ); | |
96 | ||
97 | bless($self, $class); | |
98 | ||
99 | $proto = $def_proto unless $proto; # Determine the protocol | |
f569508e HS |
100 | croak('Protocol for ping must be "icmp", "udp", "tcp", "syn", "stream", or "external"') |
101 | unless $proto =~ m/^(icmp|udp|tcp|syn|stream|external)$/; | |
e82f584b JH |
102 | $self->{"proto"} = $proto; |
103 | ||
104 | $timeout = $def_timeout unless $timeout; # Determine the timeout | |
105 | croak("Default timeout for ping must be greater than 0 seconds") | |
106 | if $timeout <= 0; | |
107 | $self->{"timeout"} = $timeout; | |
108 | ||
f569508e HS |
109 | $self->{"device"} = $device; |
110 | ||
03550e9d JH |
111 | $self->{"tos"} = $tos; |
112 | ||
e82f584b JH |
113 | $min_datasize = ($proto eq "udp") ? 1 : 0; # Determine data size |
114 | $data_size = $min_datasize unless defined($data_size) && $proto ne "tcp"; | |
115 | croak("Data for ping must be from $min_datasize to $max_datasize bytes") | |
116 | if ($data_size < $min_datasize) || ($data_size > $max_datasize); | |
117 | $data_size-- if $self->{"proto"} eq "udp"; # We provide the first byte | |
118 | $self->{"data_size"} = $data_size; | |
119 | ||
120 | $self->{"data"} = ""; # Construct data bytes | |
121 | for ($cnt = 0; $cnt < $self->{"data_size"}; $cnt++) | |
122 | { | |
123 | $self->{"data"} .= chr($cnt % 256); | |
124 | } | |
125 | ||
126 | $self->{"local_addr"} = undef; # Don't bind by default | |
9539e94f | 127 | $self->{"retrans"} = $def_factor; # Default exponential backoff rate |
c94ff782 | 128 | $self->{"econnrefused"} = undef; # Default Connection refused behavior |
f569508e | 129 | |
e82f584b JH |
130 | $self->{"seq"} = 0; # For counting packets |
131 | if ($self->{"proto"} eq "udp") # Open a socket | |
132 | { | |
133 | $self->{"proto_num"} = (getprotobyname('udp'))[2] || | |
134 | croak("Can't udp protocol by name"); | |
135 | $self->{"port_num"} = (getservbyname('echo', 'udp'))[2] || | |
136 | croak("Can't get udp echo port by name"); | |
137 | $self->{"fh"} = FileHandle->new(); | |
138 | socket($self->{"fh"}, PF_INET, SOCK_DGRAM, | |
139 | $self->{"proto_num"}) || | |
140 | croak("udp socket error - $!"); | |
f569508e HS |
141 | if ($self->{'device'}) { |
142 | setsockopt($self->{"fh"}, SOL_SOCKET, SO_BINDTODEVICE(), pack("Z*", $self->{'device'})) | |
143 | or croak "error binding to device $self->{'device'} $!"; | |
144 | } | |
03550e9d JH |
145 | if ($self->{'tos'}) { |
146 | setsockopt($self->{"fh"}, SOL_IP, IP_TOS(), pack("I*", $self->{'tos'})) | |
147 | or croak "error configuring tos to $self->{'tos'} $!"; | |
148 | } | |
e82f584b JH |
149 | } |
150 | elsif ($self->{"proto"} eq "icmp") | |
151 | { | |
f569508e | 152 | croak("icmp ping requires root privilege") if ($> and $^O ne 'VMS' and $^O ne 'cygwin'); |
e82f584b JH |
153 | $self->{"proto_num"} = (getprotobyname('icmp'))[2] || |
154 | croak("Can't get icmp protocol by name"); | |
155 | $self->{"pid"} = $$ & 0xffff; # Save lower 16 bits of pid | |
156 | $self->{"fh"} = FileHandle->new(); | |
157 | socket($self->{"fh"}, PF_INET, SOCK_RAW, $self->{"proto_num"}) || | |
158 | croak("icmp socket error - $!"); | |
f569508e HS |
159 | if ($self->{'device'}) { |
160 | setsockopt($self->{"fh"}, SOL_SOCKET, SO_BINDTODEVICE(), pack("Z*", $self->{'device'})) | |
161 | or croak "error binding to device $self->{'device'} $!"; | |
162 | } | |
03550e9d JH |
163 | if ($self->{'tos'}) { |
164 | setsockopt($self->{"fh"}, SOL_IP, IP_TOS(), pack("I*", $self->{'tos'})) | |
165 | or croak "error configuring tos to $self->{'tos'} $!"; | |
166 | } | |
e82f584b JH |
167 | } |
168 | elsif ($self->{"proto"} eq "tcp" || $self->{"proto"} eq "stream") | |
169 | { | |
170 | $self->{"proto_num"} = (getprotobyname('tcp'))[2] || | |
171 | croak("Can't get tcp protocol by name"); | |
172 | $self->{"port_num"} = (getservbyname('echo', 'tcp'))[2] || | |
173 | croak("Can't get tcp echo port by name"); | |
174 | $self->{"fh"} = FileHandle->new(); | |
175 | } | |
f569508e HS |
176 | elsif ($self->{"proto"} eq "syn") |
177 | { | |
178 | $self->{"proto_num"} = (getprotobyname('tcp'))[2] || | |
179 | croak("Can't get tcp protocol by name"); | |
180 | $self->{"port_num"} = (getservbyname('echo', 'tcp'))[2] || | |
181 | croak("Can't get tcp echo port by name"); | |
182 | if ($syn_forking) { | |
183 | $self->{"fork_rd"} = FileHandle->new(); | |
184 | $self->{"fork_wr"} = FileHandle->new(); | |
185 | pipe($self->{"fork_rd"}, $self->{"fork_wr"}); | |
186 | $self->{"fh"} = FileHandle->new(); | |
69c74a9c HS |
187 | $self->{"good"} = {}; |
188 | $self->{"bad"} = {}; | |
f569508e HS |
189 | } else { |
190 | $self->{"wbits"} = ""; | |
191 | $self->{"bad"} = {}; | |
192 | } | |
193 | $self->{"syn"} = {}; | |
194 | $self->{"stop_time"} = 0; | |
195 | } | |
196 | elsif ($self->{"proto"} eq "external") | |
197 | { | |
198 | # No preliminary work needs to be done. | |
199 | } | |
e82f584b JH |
200 | |
201 | return($self); | |
a3b93737 | 202 | } |
a0d0e21e | 203 | |
49afa5f6 JH |
204 | # Description: Set the local IP address from which pings will be sent. |
205 | # For ICMP and UDP pings, this calls bind() on the already-opened socket; | |
206 | # for TCP pings, just saves the address to be used when the socket is | |
207 | # opened. Returns non-zero if successful; croaks on error. | |
208 | sub bind | |
209 | { | |
e82f584b JH |
210 | my ($self, |
211 | $local_addr # Name or IP number of local interface | |
212 | ) = @_; | |
213 | my ($ip # Packed IP number of $local_addr | |
214 | ); | |
215 | ||
216 | croak("Usage: \$p->bind(\$local_addr)") unless @_ == 2; | |
217 | croak("already bound") if defined($self->{"local_addr"}) && | |
218 | ($self->{"proto"} eq "udp" || $self->{"proto"} eq "icmp"); | |
219 | ||
220 | $ip = inet_aton($local_addr); | |
221 | croak("nonexistent local address $local_addr") unless defined($ip); | |
222 | $self->{"local_addr"} = $ip; # Only used if proto is tcp | |
223 | ||
224 | if ($self->{"proto"} eq "udp" || $self->{"proto"} eq "icmp") | |
225 | { | |
226 | CORE::bind($self->{"fh"}, sockaddr_in(0, $ip)) || | |
227 | croak("$self->{'proto'} bind error - $!"); | |
228 | } | |
03550e9d | 229 | elsif (($self->{"proto"} ne "tcp") && ($self->{"proto"} ne "syn")) |
e82f584b JH |
230 | { |
231 | croak("Unknown protocol \"$self->{proto}\" in bind()"); | |
232 | } | |
233 | ||
234 | return 1; | |
235 | } | |
49afa5f6 | 236 | |
eb194dd9 GS |
237 | # Description: A select() wrapper that compensates for platform |
238 | # peculiarities. | |
239 | sub mselect | |
240 | { | |
241 | if ($_[3] > 0 and $^O eq 'MSWin32') { | |
242 | # On windows, select() doesn't process the message loop, | |
243 | # but sleep() will, allowing alarm() to interrupt the latter. | |
244 | # So we chop up the timeout into smaller pieces and interleave | |
245 | # select() and sleep() calls. | |
246 | my $t = $_[3]; | |
247 | my $gran = 0.5; # polling granularity in seconds | |
248 | my @args = @_; | |
249 | while (1) { | |
250 | $gran = $t if $gran > $t; | |
251 | my $nfound = select($_[0], $_[1], $_[2], $gran); | |
95d3daf0 | 252 | undef $nfound if $nfound == -1; |
eb194dd9 GS |
253 | $t -= $gran; |
254 | return $nfound if $nfound or !defined($nfound) or $t <= 0; | |
255 | ||
256 | sleep(0); | |
257 | ($_[0], $_[1], $_[2]) = @args; | |
258 | } | |
259 | } | |
260 | else { | |
95d3daf0 RGS |
261 | my $nfound = select($_[0], $_[1], $_[2], $_[3]); |
262 | undef $nfound if $nfound == -1; | |
263 | return $nfound; | |
eb194dd9 GS |
264 | } |
265 | } | |
49afa5f6 | 266 | |
3c4b39be | 267 | # Description: Allow UDP source endpoint comparison to be |
15d96390 JH |
268 | # skipped for those remote interfaces that do |
269 | # not response from the same endpoint. | |
270 | ||
271 | sub source_verify | |
272 | { | |
273 | my $self = shift; | |
5d20095f JH |
274 | $source_verify = 1 unless defined |
275 | ($source_verify = ((defined $self) && (ref $self)) ? shift() : $self); | |
15d96390 JH |
276 | } |
277 | ||
c94ff782 JH |
278 | # Description: Set whether or not the connect |
279 | # behavior should enforce remote service | |
280 | # availability as well as reachability. | |
f569508e | 281 | |
c94ff782 | 282 | sub service_check |
f569508e HS |
283 | { |
284 | my $self = shift; | |
c94ff782 JH |
285 | $self->{"econnrefused"} = 1 unless defined |
286 | ($self->{"econnrefused"} = shift()); | |
287 | } | |
288 | ||
289 | sub tcp_service_check | |
290 | { | |
291 | service_check(@_); | |
f569508e HS |
292 | } |
293 | ||
9539e94f JH |
294 | # Description: Set exponential backoff for retransmission. |
295 | # Should be > 1 to retain exponential properties. | |
296 | # If set to 0, retransmissions are disabled. | |
297 | ||
298 | sub retrans | |
299 | { | |
300 | my $self = shift; | |
301 | $self->{"retrans"} = shift; | |
302 | } | |
303 | ||
e82f584b JH |
304 | # Description: allows the module to use milliseconds as returned by |
305 | # the Time::HiRes module | |
49afa5f6 | 306 | |
e82f584b JH |
307 | $hires = 0; |
308 | sub hires | |
309 | { | |
310 | my $self = shift; | |
311 | $hires = 1 unless defined | |
312 | ($hires = ((defined $self) && (ref $self)) ? shift() : $self); | |
313 | require Time::HiRes if $hires; | |
49afa5f6 JH |
314 | } |
315 | ||
e82f584b JH |
316 | sub time |
317 | { | |
318 | return $hires ? Time::HiRes::time() : CORE::time(); | |
319 | } | |
49afa5f6 | 320 | |
9c36735d JH |
321 | # Description: Sets or clears the O_NONBLOCK flag on a file handle. |
322 | sub socket_blocking_mode | |
323 | { | |
324 | my ($self, | |
325 | $fh, # the file handle whose flags are to be modified | |
326 | $block) = @_; # if true then set the blocking | |
327 | # mode (clear O_NONBLOCK), otherwise | |
328 | # set the non-blocking mode (set O_NONBLOCK) | |
329 | ||
330 | my $flags; | |
d135e082 CB |
331 | if ($^O eq 'MSWin32' || $^O eq 'VMS') { |
332 | # FIONBIO enables non-blocking sockets on windows and vms. | |
333 | # FIONBIO is (0x80000000|(4<<16)|(ord('f')<<8)|126), as per winsock.h, ioctl.h | |
eb194dd9 GS |
334 | my $f = 0x8004667e; |
335 | my $v = pack("L", $block ? 0 : 1); | |
336 | ioctl($fh, $f, $v) or croak("ioctl failed: $!"); | |
337 | return; | |
338 | } | |
9c36735d JH |
339 | if ($flags = fcntl($fh, F_GETFL, 0)) { |
340 | $flags = $block ? ($flags & ~O_NONBLOCK) : ($flags | O_NONBLOCK); | |
341 | if (!fcntl($fh, F_SETFL, $flags)) { | |
342 | croak("fcntl F_SETFL: $!"); | |
343 | } | |
344 | } else { | |
345 | croak("fcntl F_GETFL: $!"); | |
346 | } | |
347 | } | |
348 | ||
a3b93737 RM |
349 | # Description: Ping a host name or IP number with an optional timeout. |
350 | # First lookup the host, and return undef if it is not found. Otherwise | |
b124990b | 351 | # perform the specific ping method based on the protocol. Return the |
a3b93737 RM |
352 | # result of the ping. |
353 | ||
354 | sub ping | |
355 | { | |
e82f584b JH |
356 | my ($self, |
357 | $host, # Name or IP number of host to ping | |
358 | $timeout, # Seconds after which ping times out | |
359 | ) = @_; | |
360 | my ($ip, # Packed IP number of $host | |
361 | $ret, # The return value | |
362 | $ping_time, # When ping began | |
363 | ); | |
364 | ||
365 | croak("Usage: \$p->ping(\$host [, \$timeout])") unless @_ == 2 || @_ == 3; | |
366 | $timeout = $self->{"timeout"} unless $timeout; | |
367 | croak("Timeout must be greater than 0 seconds") if $timeout <= 0; | |
368 | ||
369 | $ip = inet_aton($host); | |
c94ff782 | 370 | return () unless defined($ip); # Does host exist? |
e82f584b JH |
371 | |
372 | # Dispatch to the appropriate routine. | |
373 | $ping_time = &time(); | |
374 | if ($self->{"proto"} eq "external") { | |
375 | $ret = $self->ping_external($ip, $timeout); | |
376 | } | |
377 | elsif ($self->{"proto"} eq "udp") { | |
378 | $ret = $self->ping_udp($ip, $timeout); | |
379 | } | |
380 | elsif ($self->{"proto"} eq "icmp") { | |
381 | $ret = $self->ping_icmp($ip, $timeout); | |
382 | } | |
383 | elsif ($self->{"proto"} eq "tcp") { | |
384 | $ret = $self->ping_tcp($ip, $timeout); | |
385 | } | |
386 | elsif ($self->{"proto"} eq "stream") { | |
387 | $ret = $self->ping_stream($ip, $timeout); | |
f569508e HS |
388 | } |
389 | elsif ($self->{"proto"} eq "syn") { | |
390 | $ret = $self->ping_syn($host, $ip, $ping_time, $ping_time+$timeout); | |
e82f584b | 391 | } else { |
787ecdfa | 392 | croak("Unknown protocol \"$self->{proto}\" in ping()"); |
e82f584b JH |
393 | } |
394 | ||
395 | return wantarray ? ($ret, &time() - $ping_time, inet_ntoa($ip)) : $ret; | |
787ecdfa JH |
396 | } |
397 | ||
398 | # Uses Net::Ping::External to do an external ping. | |
399 | sub ping_external { | |
400 | my ($self, | |
401 | $ip, # Packed IP number of the host | |
402 | $timeout # Seconds after which ping times out | |
403 | ) = @_; | |
404 | ||
b124990b JH |
405 | eval { require Net::Ping::External; } |
406 | or croak('Protocol "external" not supported on your system: Net::Ping::External not found'); | |
787ecdfa | 407 | return Net::Ping::External::ping(ip => $ip, timeout => $timeout); |
a3b93737 | 408 | } |
a0d0e21e | 409 | |
46b9c7d8 GA |
410 | use constant ICMP_ECHOREPLY => 0; # ICMP packet types |
411 | use constant ICMP_UNREACHABLE => 3; # ICMP packet types | |
412 | use constant ICMP_ECHO => 8; | |
413 | use constant ICMP_STRUCT => "C2 n3 A"; # Structure of a minimal ICMP packet | |
414 | use constant SUBCODE => 0; # No ICMP subcode for ECHO and ECHOREPLY | |
415 | use constant ICMP_FLAGS => 0; # No special flags for send or recv | |
416 | use constant ICMP_PORT => 0; # No port with ICMP | |
49afa5f6 | 417 | |
a3b93737 RM |
418 | sub ping_icmp |
419 | { | |
e82f584b JH |
420 | my ($self, |
421 | $ip, # Packed IP number of the host | |
422 | $timeout # Seconds after which ping times out | |
423 | ) = @_; | |
424 | ||
425 | my ($saddr, # sockaddr_in with port and ip | |
426 | $checksum, # Checksum of ICMP packet | |
427 | $msg, # ICMP packet to send | |
428 | $len_msg, # Length of $msg | |
429 | $rbits, # Read bits, filehandles for reading | |
430 | $nfound, # Number of ready filehandles found | |
431 | $finish_time, # Time ping should be finished | |
432 | $done, # set to 1 when we are done | |
433 | $ret, # Return value | |
434 | $recv_msg, # Received message including IP header | |
435 | $from_saddr, # sockaddr_in of sender | |
436 | $from_port, # Port packet was sent from | |
437 | $from_ip, # Packed IP of sender | |
438 | $from_type, # ICMP type | |
439 | $from_subcode, # ICMP subcode | |
440 | $from_chk, # ICMP packet checksum | |
441 | $from_pid, # ICMP packet id | |
442 | $from_seq, # ICMP packet sequence | |
443 | $from_msg # ICMP message | |
444 | ); | |
445 | ||
446 | $self->{"seq"} = ($self->{"seq"} + 1) % 65536; # Increment sequence | |
447 | $checksum = 0; # No checksum for starters | |
448 | $msg = pack(ICMP_STRUCT . $self->{"data_size"}, ICMP_ECHO, SUBCODE, | |
449 | $checksum, $self->{"pid"}, $self->{"seq"}, $self->{"data"}); | |
450 | $checksum = Net::Ping->checksum($msg); | |
451 | $msg = pack(ICMP_STRUCT . $self->{"data_size"}, ICMP_ECHO, SUBCODE, | |
452 | $checksum, $self->{"pid"}, $self->{"seq"}, $self->{"data"}); | |
453 | $len_msg = length($msg); | |
454 | $saddr = sockaddr_in(ICMP_PORT, $ip); | |
9c36735d JH |
455 | $self->{"from_ip"} = undef; |
456 | $self->{"from_type"} = undef; | |
457 | $self->{"from_subcode"} = undef; | |
e82f584b JH |
458 | send($self->{"fh"}, $msg, ICMP_FLAGS, $saddr); # Send the message |
459 | ||
460 | $rbits = ""; | |
461 | vec($rbits, $self->{"fh"}->fileno(), 1) = 1; | |
462 | $ret = 0; | |
463 | $done = 0; | |
464 | $finish_time = &time() + $timeout; # Must be done by this time | |
465 | while (!$done && $timeout > 0) # Keep trying if we have time | |
466 | { | |
eb194dd9 | 467 | $nfound = mselect((my $rout=$rbits), undef, undef, $timeout); # Wait for packet |
e82f584b | 468 | $timeout = $finish_time - &time(); # Get remaining time |
95d3daf0 | 469 | if (!defined($nfound)) # Hmm, a strange error |
a3b93737 | 470 | { |
e82f584b JH |
471 | $ret = undef; |
472 | $done = 1; | |
473 | } | |
474 | elsif ($nfound) # Got a packet from somewhere | |
475 | { | |
476 | $recv_msg = ""; | |
9539e94f JH |
477 | $from_pid = -1; |
478 | $from_seq = -1; | |
e82f584b JH |
479 | $from_saddr = recv($self->{"fh"}, $recv_msg, 1500, ICMP_FLAGS); |
480 | ($from_port, $from_ip) = sockaddr_in($from_saddr); | |
9c36735d | 481 | ($from_type, $from_subcode) = unpack("C2", substr($recv_msg, 20, 2)); |
9539e94f JH |
482 | if ($from_type == ICMP_ECHOREPLY) { |
483 | ($from_pid, $from_seq) = unpack("n3", substr($recv_msg, 24, 4)) | |
484 | if length $recv_msg >= 28; | |
9c36735d | 485 | } else { |
9539e94f JH |
486 | ($from_pid, $from_seq) = unpack("n3", substr($recv_msg, 52, 4)) |
487 | if length $recv_msg >= 56; | |
9c36735d JH |
488 | } |
489 | $self->{"from_ip"} = $from_ip; | |
490 | $self->{"from_type"} = $from_type; | |
491 | $self->{"from_subcode"} = $from_subcode; | |
492 | if (($from_pid == $self->{"pid"}) && # Does the packet check out? | |
af96568d | 493 | (! $source_verify || (inet_ntoa($from_ip) eq inet_ntoa($ip))) && |
9c36735d | 494 | ($from_seq == $self->{"seq"})) { |
46b9c7d8 | 495 | if ($from_type == ICMP_ECHOREPLY) { |
9c36735d | 496 | $ret = 1; |
46b9c7d8 GA |
497 | $done = 1; |
498 | } elsif ($from_type == ICMP_UNREACHABLE) { | |
499 | $done = 1; | |
9c36735d | 500 | } |
e82f584b | 501 | } |
9c36735d | 502 | } else { # Oops, timed out |
e82f584b JH |
503 | $done = 1; |
504 | } | |
505 | } | |
506 | return $ret; | |
a3b93737 RM |
507 | } |
508 | ||
9c36735d JH |
509 | sub icmp_result { |
510 | my ($self) = @_; | |
511 | my $ip = $self->{"from_ip"} || ""; | |
512 | $ip = "\0\0\0\0" unless 4 == length $ip; | |
513 | return (inet_ntoa($ip),($self->{"from_type"} || 0), ($self->{"from_subcode"} || 0)); | |
514 | } | |
515 | ||
a3b93737 RM |
516 | # Description: Do a checksum on the message. Basically sum all of |
517 | # the short words and fold the high order bits into the low order bits. | |
518 | ||
519 | sub checksum | |
520 | { | |
e82f584b JH |
521 | my ($class, |
522 | $msg # The message to checksum | |
523 | ) = @_; | |
524 | my ($len_msg, # Length of the message | |
525 | $num_short, # The number of short words in the message | |
526 | $short, # One short word | |
527 | $chk # The checksum | |
528 | ); | |
529 | ||
530 | $len_msg = length($msg); | |
531 | $num_short = int($len_msg / 2); | |
532 | $chk = 0; | |
9c36735d | 533 | foreach $short (unpack("n$num_short", $msg)) |
e82f584b JH |
534 | { |
535 | $chk += $short; | |
536 | } # Add the odd byte in | |
537 | $chk += (unpack("C", substr($msg, $len_msg - 1, 1)) << 8) if $len_msg % 2; | |
538 | $chk = ($chk >> 16) + ($chk & 0xffff); # Fold high into low | |
539 | return(~(($chk >> 16) + $chk) & 0xffff); # Again and complement | |
a3b93737 RM |
540 | } |
541 | ||
787ecdfa | 542 | |
b124990b JH |
543 | # Description: Perform a tcp echo ping. Since a tcp connection is |
544 | # host specific, we have to open and close each connection here. We | |
545 | # can't just leave a socket open. Because of the robust nature of | |
546 | # tcp, it will take a while before it gives up trying to establish a | |
547 | # connection. Therefore, we use select() on a non-blocking socket to | |
548 | # check against our timeout. No data bytes are actually | |
549 | # sent since the successful establishment of a connection is proof | |
550 | # enough of the reachability of the remote host. Also, tcp is | |
551 | # expensive and doesn't need our help to add to the overhead. | |
552 | ||
553 | sub ping_tcp | |
787ecdfa | 554 | { |
e82f584b JH |
555 | my ($self, |
556 | $ip, # Packed IP number of the host | |
557 | $timeout # Seconds after which ping times out | |
558 | ) = @_; | |
559 | my ($ret # The return value | |
560 | ); | |
561 | ||
9c36735d | 562 | $! = 0; |
e82f584b | 563 | $ret = $self -> tcp_connect( $ip, $timeout); |
c94ff782 | 564 | if (!$self->{"econnrefused"} && |
f569508e HS |
565 | $! == ECONNREFUSED) { |
566 | $ret = 1; # "Connection refused" means reachable | |
567 | } | |
e82f584b JH |
568 | $self->{"fh"}->close(); |
569 | return $ret; | |
787ecdfa JH |
570 | } |
571 | ||
b124990b | 572 | sub tcp_connect |
787ecdfa | 573 | { |
e82f584b JH |
574 | my ($self, |
575 | $ip, # Packed IP number of the host | |
576 | $timeout # Seconds after which connect times out | |
577 | ) = @_; | |
578 | my ($saddr); # Packed IP and Port | |
b124990b | 579 | |
e82f584b | 580 | $saddr = sockaddr_in($self->{"port_num"}, $ip); |
b124990b | 581 | |
e82f584b | 582 | my $ret = 0; # Default to unreachable |
b124990b | 583 | |
e82f584b JH |
584 | my $do_socket = sub { |
585 | socket($self->{"fh"}, PF_INET, SOCK_STREAM, $self->{"proto_num"}) || | |
586 | croak("tcp socket error - $!"); | |
587 | if (defined $self->{"local_addr"} && | |
588 | !CORE::bind($self->{"fh"}, sockaddr_in(0, $self->{"local_addr"}))) { | |
589 | croak("tcp bind error - $!"); | |
590 | } | |
f569508e HS |
591 | if ($self->{'device'}) { |
592 | setsockopt($self->{"fh"}, SOL_SOCKET, SO_BINDTODEVICE(), pack("Z*", $self->{'device'})) | |
593 | or croak("error binding to device $self->{'device'} $!"); | |
594 | } | |
03550e9d JH |
595 | if ($self->{'tos'}) { |
596 | setsockopt($self->{"fh"}, SOL_IP, IP_TOS(), pack("I*", $self->{'tos'})) | |
597 | or croak "error configuring tos to $self->{'tos'} $!"; | |
598 | } | |
e82f584b JH |
599 | }; |
600 | my $do_connect = sub { | |
9c36735d | 601 | $self->{"ip"} = $ip; |
6dbac12b GS |
602 | # ECONNREFUSED is 10061 on MSWin32. If we pass it as child error through $?, |
603 | # we'll get (10061 & 255) = 77, so we cannot check it in the parent process. | |
604 | return ($ret = connect($self->{"fh"}, $saddr) || ($! == ECONNREFUSED && !$self->{"econnrefused"})); | |
e82f584b | 605 | }; |
9c36735d JH |
606 | my $do_connect_nb = sub { |
607 | # Set O_NONBLOCK property on filehandle | |
608 | $self->socket_blocking_mode($self->{"fh"}, 0); | |
609 | ||
610 | # start the connection attempt | |
611 | if (!connect($self->{"fh"}, $saddr)) { | |
612 | if ($! == ECONNREFUSED) { | |
c94ff782 | 613 | $ret = 1 unless $self->{"econnrefused"}; |
eb194dd9 | 614 | } elsif ($! != EINPROGRESS && ($^O ne 'MSWin32' || $! != EWOULDBLOCK)) { |
9c36735d | 615 | # EINPROGRESS is the expected error code after a connect() |
c94ff782 JH |
616 | # on a non-blocking socket. But if the kernel immediately |
617 | # determined that this connect() will never work, | |
618 | # Simply respond with "unreachable" status. | |
619 | # (This can occur on some platforms with errno | |
620 | # EHOSTUNREACH or ENETUNREACH.) | |
621 | return 0; | |
622 | } else { | |
623 | # Got the expected EINPROGRESS. | |
624 | # Just wait for connection completion... | |
eb194dd9 GS |
625 | my ($wbits, $wout, $wexc); |
626 | $wout = $wexc = $wbits = ""; | |
9c36735d JH |
627 | vec($wbits, $self->{"fh"}->fileno, 1) = 1; |
628 | ||
eb194dd9 GS |
629 | my $nfound = mselect(undef, |
630 | ($wout = $wbits), | |
631 | ($^O eq 'MSWin32' ? ($wexc = $wbits) : undef), | |
632 | $timeout); | |
9c36735d JH |
633 | warn("select: $!") unless defined $nfound; |
634 | ||
635 | if ($nfound && vec($wout, $self->{"fh"}->fileno, 1)) { | |
636 | # the socket is ready for writing so the connection | |
637 | # attempt completed. test whether the connection | |
638 | # attempt was successful or not | |
639 | ||
640 | if (getpeername($self->{"fh"})) { | |
641 | # Connection established to remote host | |
642 | $ret = 1; | |
643 | } else { | |
644 | # TCP ACK will never come from this host | |
645 | # because there was an error connecting. | |
e82f584b | 646 | |
9c36735d JH |
647 | # This should set $! to the correct error. |
648 | my $char; | |
649 | sysread($self->{"fh"},$char,1); | |
650 | $! = ECONNREFUSED if ($! == EAGAIN && $^O =~ /cygwin/i); | |
e82f584b | 651 | |
c94ff782 | 652 | $ret = 1 if (!$self->{"econnrefused"} |
9c36735d JH |
653 | && $! == ECONNREFUSED); |
654 | } | |
655 | } else { | |
eb194dd9 GS |
656 | # the connection attempt timed out (or there were connect |
657 | # errors on Windows) | |
658 | if ($^O =~ 'MSWin32') { | |
659 | # If the connect will fail on a non-blocking socket, | |
660 | # winsock reports ECONNREFUSED as an exception, and we | |
661 | # need to fetch the socket-level error code via getsockopt() | |
662 | # instead of using the thread-level error code that is in $!. | |
663 | if ($nfound && vec($wexc, $self->{"fh"}->fileno, 1)) { | |
664 | $! = unpack("i", getsockopt($self->{"fh"}, SOL_SOCKET, | |
665 | SO_ERROR)); | |
666 | } | |
667 | } | |
9c36735d JH |
668 | } |
669 | } | |
670 | } else { | |
671 | # Connection established to remote host | |
672 | $ret = 1; | |
673 | } | |
674 | ||
675 | # Unset O_NONBLOCK property on filehandle | |
676 | $self->socket_blocking_mode($self->{"fh"}, 1); | |
677 | $self->{"ip"} = $ip; | |
678 | return $ret; | |
679 | }; | |
680 | ||
681 | if ($syn_forking) { | |
682 | # Buggy Winsock API doesn't allow nonblocking connect. | |
e82f584b JH |
683 | # Hence, if our OS is Windows, we need to create a separate |
684 | # process to do the blocking connect attempt. | |
eb194dd9 GS |
685 | # XXX Above comments are not true at least for Win2K, where |
686 | # nonblocking connect works. | |
e82f584b JH |
687 | |
688 | $| = 1; # Clear buffer prior to fork to prevent duplicate flushing. | |
9c36735d JH |
689 | $self->{'tcp_chld'} = fork; |
690 | if (!$self->{'tcp_chld'}) { | |
691 | if (!defined $self->{'tcp_chld'}) { | |
e82f584b | 692 | # Fork did not work |
9c36735d | 693 | warn "Fork error: $!"; |
e82f584b | 694 | return 0; |
b124990b | 695 | } |
b124990b JH |
696 | &{ $do_socket }(); |
697 | ||
e82f584b | 698 | # Try a slow blocking connect() call |
9c36735d | 699 | # and report the status to the parent. |
e82f584b JH |
700 | if ( &{ $do_connect }() ) { |
701 | $self->{"fh"}->close(); | |
702 | # No error | |
703 | exit 0; | |
b124990b | 704 | } else { |
e82f584b | 705 | # Pass the error status to the parent |
6dbac12b GS |
706 | # Make sure that $! <= 255 |
707 | exit($! <= 255 ? $! : 255); | |
b124990b | 708 | } |
e82f584b | 709 | } |
b124990b | 710 | |
e82f584b JH |
711 | &{ $do_socket }(); |
712 | ||
713 | my $patience = &time() + $timeout; | |
714 | ||
9c36735d JH |
715 | my ($child, $child_errno); |
716 | $? = 0; $child_errno = 0; | |
e82f584b JH |
717 | # Wait up to the timeout |
718 | # And clean off the zombie | |
719 | do { | |
9c36735d JH |
720 | $child = waitpid($self->{'tcp_chld'}, &WNOHANG()); |
721 | $child_errno = $? >> 8; | |
e82f584b | 722 | select(undef, undef, undef, 0.1); |
9c36735d JH |
723 | } while &time() < $patience && $child != $self->{'tcp_chld'}; |
724 | ||
725 | if ($child == $self->{'tcp_chld'}) { | |
726 | if ($self->{"proto"} eq "stream") { | |
727 | # We need the socket connected here, in parent | |
728 | # Should be safe to connect because the child finished | |
729 | # within the timeout | |
730 | &{ $do_connect }(); | |
731 | } | |
6dbac12b GS |
732 | # $ret cannot be set by the child process |
733 | $ret = !$child_errno; | |
e82f584b JH |
734 | } else { |
735 | # Time must have run out. | |
e82f584b | 736 | # Put that choking client out of its misery |
9c36735d | 737 | kill "KILL", $self->{'tcp_chld'}; |
e82f584b | 738 | # Clean off the zombie |
9c36735d | 739 | waitpid($self->{'tcp_chld'}, 0); |
e82f584b | 740 | $ret = 0; |
b124990b | 741 | } |
9c36735d JH |
742 | delete $self->{'tcp_chld'}; |
743 | $! = $child_errno; | |
744 | } else { | |
e82f584b JH |
745 | # Otherwise don't waste the resources to fork |
746 | ||
747 | &{ $do_socket }(); | |
748 | ||
9c36735d | 749 | &{ $do_connect_nb }(); |
e82f584b | 750 | } |
787ecdfa | 751 | |
e82f584b | 752 | return $ret; |
787ecdfa JH |
753 | } |
754 | ||
9c36735d JH |
755 | sub DESTROY { |
756 | my $self = shift; | |
757 | if ($self->{'proto'} eq 'tcp' && | |
758 | $self->{'tcp_chld'}) { | |
759 | # Put that choking client out of its misery | |
760 | kill "KILL", $self->{'tcp_chld'}; | |
761 | # Clean off the zombie | |
762 | waitpid($self->{'tcp_chld'}, 0); | |
763 | } | |
764 | } | |
765 | ||
787ecdfa JH |
766 | # This writes the given string to the socket and then reads it |
767 | # back. It returns 1 on success, 0 on failure. | |
768 | sub tcp_echo | |
769 | { | |
e82f584b JH |
770 | my $self = shift; |
771 | my $timeout = shift; | |
772 | my $pingstring = shift; | |
773 | ||
774 | my $ret = undef; | |
775 | my $time = &time(); | |
776 | my $wrstr = $pingstring; | |
777 | my $rdstr = ""; | |
778 | ||
779 | eval <<'EOM'; | |
780 | do { | |
781 | my $rin = ""; | |
782 | vec($rin, $self->{"fh"}->fileno(), 1) = 1; | |
783 | ||
784 | my $rout = undef; | |
785 | if($wrstr) { | |
786 | $rout = ""; | |
787 | vec($rout, $self->{"fh"}->fileno(), 1) = 1; | |
788 | } | |
789 | ||
eb194dd9 | 790 | if(mselect($rin, $rout, undef, ($time + $timeout) - &time())) { |
e82f584b JH |
791 | |
792 | if($rout && vec($rout,$self->{"fh"}->fileno(),1)) { | |
9c36735d | 793 | my $num = syswrite($self->{"fh"}, $wrstr, length $wrstr); |
e82f584b JH |
794 | if($num) { |
795 | # If it was a partial write, update and try again. | |
796 | $wrstr = substr($wrstr,$num); | |
797 | } else { | |
798 | # There was an error. | |
799 | $ret = 0; | |
800 | } | |
801 | } | |
802 | ||
803 | if(vec($rin,$self->{"fh"}->fileno(),1)) { | |
804 | my $reply; | |
805 | if(sysread($self->{"fh"},$reply,length($pingstring)-length($rdstr))) { | |
806 | $rdstr .= $reply; | |
807 | $ret = 1 if $rdstr eq $pingstring; | |
808 | } else { | |
809 | # There was an error. | |
810 | $ret = 0; | |
811 | } | |
812 | } | |
813 | ||
814 | } | |
815 | } until &time() > ($time + $timeout) || defined($ret); | |
787ecdfa JH |
816 | EOM |
817 | ||
e82f584b | 818 | return $ret; |
787ecdfa JH |
819 | } |
820 | ||
787ecdfa | 821 | |
787ecdfa | 822 | |
787ecdfa JH |
823 | |
824 | # Description: Perform a stream ping. If the tcp connection isn't | |
825 | # already open, it opens it. It then sends some data and waits for | |
826 | # a reply. It leaves the stream open on exit. | |
827 | ||
828 | sub ping_stream | |
829 | { | |
e82f584b JH |
830 | my ($self, |
831 | $ip, # Packed IP number of the host | |
832 | $timeout # Seconds after which ping times out | |
833 | ) = @_; | |
072620d9 | 834 | |
e82f584b JH |
835 | # Open the stream if it's not already open |
836 | if(!defined $self->{"fh"}->fileno()) { | |
837 | $self->tcp_connect($ip, $timeout) or return 0; | |
838 | } | |
787ecdfa | 839 | |
e82f584b JH |
840 | croak "tried to switch servers while stream pinging" |
841 | if $self->{"ip"} ne $ip; | |
842 | ||
843 | return $self->tcp_echo($timeout, $pingstring); | |
787ecdfa JH |
844 | } |
845 | ||
846 | # Description: opens the stream. You would do this if you want to | |
847 | # separate the overhead of opening the stream from the first ping. | |
848 | ||
849 | sub open | |
850 | { | |
e82f584b JH |
851 | my ($self, |
852 | $host, # Host or IP address | |
853 | $timeout # Seconds after which open times out | |
854 | ) = @_; | |
855 | ||
856 | my ($ip); # Packed IP number of the host | |
857 | $ip = inet_aton($host); | |
858 | $timeout = $self->{"timeout"} unless $timeout; | |
859 | ||
860 | if($self->{"proto"} eq "stream") { | |
861 | if(defined($self->{"fh"}->fileno())) { | |
862 | croak("socket is already open"); | |
863 | } else { | |
864 | $self->tcp_connect($ip, $timeout); | |
b124990b | 865 | } |
e82f584b | 866 | } |
072620d9 SB |
867 | } |
868 | ||
b124990b | 869 | |
a3b93737 RM |
870 | # Description: Perform a udp echo ping. Construct a message of |
871 | # at least the one-byte sequence number and any additional data bytes. | |
872 | # Send the message out and wait for a message to come back. If we | |
873 | # get a message, make sure all of its parts match. If they do, we are | |
874 | # done. Otherwise go back and wait for the message until we run out | |
875 | # of time. Return the result of our efforts. | |
876 | ||
49afa5f6 | 877 | use constant UDP_FLAGS => 0; # Nothing special on send or recv |
a3b93737 RM |
878 | sub ping_udp |
879 | { | |
e82f584b JH |
880 | my ($self, |
881 | $ip, # Packed IP number of the host | |
882 | $timeout # Seconds after which ping times out | |
883 | ) = @_; | |
884 | ||
885 | my ($saddr, # sockaddr_in with port and ip | |
886 | $ret, # The return value | |
887 | $msg, # Message to be echoed | |
888 | $finish_time, # Time ping should be finished | |
9539e94f JH |
889 | $flush, # Whether socket needs to be disconnected |
890 | $connect, # Whether socket needs to be connected | |
e82f584b JH |
891 | $done, # Set to 1 when we are done pinging |
892 | $rbits, # Read bits, filehandles for reading | |
893 | $nfound, # Number of ready filehandles found | |
894 | $from_saddr, # sockaddr_in of sender | |
895 | $from_msg, # Characters echoed by $host | |
896 | $from_port, # Port message was echoed from | |
897 | $from_ip # Packed IP number of sender | |
898 | ); | |
899 | ||
900 | $saddr = sockaddr_in($self->{"port_num"}, $ip); | |
901 | $self->{"seq"} = ($self->{"seq"} + 1) % 256; # Increment sequence | |
902 | $msg = chr($self->{"seq"}) . $self->{"data"}; # Add data if any | |
9539e94f JH |
903 | |
904 | if ($self->{"connected"}) { | |
905 | if ($self->{"connected"} ne $saddr) { | |
906 | # Still connected to wrong destination. | |
907 | # Need to flush out the old one. | |
908 | $flush = 1; | |
909 | } | |
910 | } else { | |
911 | # Not connected yet. | |
912 | # Need to connect() before send() | |
913 | $connect = 1; | |
914 | } | |
915 | ||
c94ff782 JH |
916 | # Have to connect() and send() instead of sendto() |
917 | # in order to pick up on the ECONNREFUSED setting | |
918 | # from recv() or double send() errno as utilized in | |
919 | # the concept by rdw @ perlmonks. See: | |
920 | # http://perlmonks.thepen.com/42898.html | |
9539e94f JH |
921 | if ($flush) { |
922 | # Need to socket() again to flush the descriptor | |
923 | # This will disconnect from the old saddr. | |
924 | socket($self->{"fh"}, PF_INET, SOCK_DGRAM, | |
925 | $self->{"proto_num"}); | |
926 | } | |
927 | # Connect the socket if it isn't already connected | |
928 | # to the right destination. | |
929 | if ($flush || $connect) { | |
930 | connect($self->{"fh"}, $saddr); # Tie destination to socket | |
931 | $self->{"connected"} = $saddr; | |
932 | } | |
c94ff782 | 933 | send($self->{"fh"}, $msg, UDP_FLAGS); # Send it |
e82f584b JH |
934 | |
935 | $rbits = ""; | |
936 | vec($rbits, $self->{"fh"}->fileno(), 1) = 1; | |
937 | $ret = 0; # Default to unreachable | |
938 | $done = 0; | |
c94ff782 | 939 | my $retrans = 0.01; |
9539e94f | 940 | my $factor = $self->{"retrans"}; |
e82f584b JH |
941 | $finish_time = &time() + $timeout; # Ping needs to be done by then |
942 | while (!$done && $timeout > 0) | |
943 | { | |
9539e94f JH |
944 | if ($factor > 1) |
945 | { | |
946 | $timeout = $retrans if $timeout > $retrans; | |
947 | $retrans*= $factor; # Exponential backoff | |
948 | } | |
eb194dd9 | 949 | $nfound = mselect((my $rout=$rbits), undef, undef, $timeout); # Wait for response |
c94ff782 | 950 | my $why = $!; |
e82f584b JH |
951 | $timeout = $finish_time - &time(); # Get remaining time |
952 | ||
953 | if (!defined($nfound)) # Hmm, a strange error | |
a3b93737 | 954 | { |
e82f584b JH |
955 | $ret = undef; |
956 | $done = 1; | |
a3b93737 | 957 | } |
e82f584b JH |
958 | elsif ($nfound) # A packet is waiting |
959 | { | |
960 | $from_msg = ""; | |
c94ff782 JH |
961 | $from_saddr = recv($self->{"fh"}, $from_msg, 1500, UDP_FLAGS); |
962 | if (!$from_saddr) { | |
963 | # For example an unreachable host will make recv() fail. | |
964 | if (!$self->{"econnrefused"} && | |
9539e94f JH |
965 | ($! == ECONNREFUSED || |
966 | $! == ECONNRESET)) { | |
c94ff782 JH |
967 | # "Connection refused" means reachable |
968 | # Good, continue | |
969 | $ret = 1; | |
970 | } | |
e82f584b | 971 | $done = 1; |
c94ff782 JH |
972 | } else { |
973 | ($from_port, $from_ip) = sockaddr_in($from_saddr); | |
974 | if (!$source_verify || | |
975 | (($from_ip eq $ip) && # Does the packet check out? | |
976 | ($from_port == $self->{"port_num"}) && | |
977 | ($from_msg eq $msg))) | |
978 | { | |
979 | $ret = 1; # It's a winner | |
980 | $done = 1; | |
981 | } | |
e82f584b JH |
982 | } |
983 | } | |
c94ff782 | 984 | elsif ($timeout <= 0) # Oops, timed out |
e82f584b JH |
985 | { |
986 | $done = 1; | |
987 | } | |
c94ff782 JH |
988 | else |
989 | { | |
990 | # Send another in case the last one dropped | |
991 | if (send($self->{"fh"}, $msg, UDP_FLAGS)) { | |
992 | # Another send worked? The previous udp packet | |
993 | # must have gotten lost or is still in transit. | |
994 | # Hopefully this new packet will arrive safely. | |
995 | } else { | |
996 | if (!$self->{"econnrefused"} && | |
997 | $! == ECONNREFUSED) { | |
998 | # "Connection refused" means reachable | |
999 | # Good, continue | |
1000 | $ret = 1; | |
1001 | } | |
1002 | $done = 1; | |
1003 | } | |
1004 | } | |
e82f584b | 1005 | } |
a5a165b1 | 1006 | return $ret; |
b124990b | 1007 | } |
a0d0e21e | 1008 | |
f569508e HS |
1009 | # Description: Send a TCP SYN packet to host specified. |
1010 | sub ping_syn | |
1011 | { | |
1012 | my $self = shift; | |
1013 | my $host = shift; | |
1014 | my $ip = shift; | |
1015 | my $start_time = shift; | |
1016 | my $stop_time = shift; | |
1017 | ||
1018 | if ($syn_forking) { | |
1019 | return $self->ping_syn_fork($host, $ip, $start_time, $stop_time); | |
1020 | } | |
1021 | ||
1022 | my $fh = FileHandle->new(); | |
1023 | my $saddr = sockaddr_in($self->{"port_num"}, $ip); | |
1024 | ||
1025 | # Create TCP socket | |
1026 | if (!socket ($fh, PF_INET, SOCK_STREAM, $self->{"proto_num"})) { | |
1027 | croak("tcp socket error - $!"); | |
1028 | } | |
1029 | ||
1030 | if (defined $self->{"local_addr"} && | |
1031 | !CORE::bind($fh, sockaddr_in(0, $self->{"local_addr"}))) { | |
1032 | croak("tcp bind error - $!"); | |
1033 | } | |
1034 | ||
1035 | if ($self->{'device'}) { | |
1036 | setsockopt($fh, SOL_SOCKET, SO_BINDTODEVICE(), pack("Z*", $self->{'device'})) | |
1037 | or croak("error binding to device $self->{'device'} $!"); | |
1038 | } | |
03550e9d JH |
1039 | if ($self->{'tos'}) { |
1040 | setsockopt($fh, SOL_IP, IP_TOS(), pack("I*", $self->{'tos'})) | |
1041 | or croak "error configuring tos to $self->{'tos'} $!"; | |
1042 | } | |
f569508e | 1043 | # Set O_NONBLOCK property on filehandle |
9c36735d | 1044 | $self->socket_blocking_mode($fh, 0); |
f569508e HS |
1045 | |
1046 | # Attempt the non-blocking connect | |
1047 | # by just sending the TCP SYN packet | |
1048 | if (connect($fh, $saddr)) { | |
1049 | # Non-blocking, yet still connected? | |
69c74a9c HS |
1050 | # Must have connected very quickly, |
1051 | # or else it wasn't very non-blocking. | |
1052 | #warn "WARNING: Nonblocking connect connected anyway? ($^O)"; | |
1053 | } else { | |
f569508e | 1054 | # Error occurred connecting. |
eb194dd9 | 1055 | if ($! == EINPROGRESS || ($^O eq 'MSWin32' && $! == EWOULDBLOCK)) { |
69c74a9c HS |
1056 | # The connection is just still in progress. |
1057 | # This is the expected condition. | |
1058 | } else { | |
1059 | # Just save the error and continue on. | |
1060 | # The ack() can check the status later. | |
f569508e | 1061 | $self->{"bad"}->{$host} = $!; |
f569508e HS |
1062 | } |
1063 | } | |
1064 | ||
1065 | my $entry = [ $host, $ip, $fh, $start_time, $stop_time ]; | |
1066 | $self->{"syn"}->{$fh->fileno} = $entry; | |
1067 | if ($self->{"stop_time"} < $stop_time) { | |
1068 | $self->{"stop_time"} = $stop_time; | |
1069 | } | |
1070 | vec($self->{"wbits"}, $fh->fileno, 1) = 1; | |
1071 | ||
1072 | return 1; | |
1073 | } | |
1074 | ||
1075 | sub ping_syn_fork { | |
1076 | my ($self, $host, $ip, $start_time, $stop_time) = @_; | |
1077 | ||
1078 | # Buggy Winsock API doesn't allow nonblocking connect. | |
1079 | # Hence, if our OS is Windows, we need to create a separate | |
1080 | # process to do the blocking connect attempt. | |
1081 | my $pid = fork(); | |
1082 | if (defined $pid) { | |
1083 | if ($pid) { | |
1084 | # Parent process | |
1085 | my $entry = [ $host, $ip, $pid, $start_time, $stop_time ]; | |
1086 | $self->{"syn"}->{$pid} = $entry; | |
1087 | if ($self->{"stop_time"} < $stop_time) { | |
1088 | $self->{"stop_time"} = $stop_time; | |
1089 | } | |
1090 | } else { | |
1091 | # Child process | |
1092 | my $saddr = sockaddr_in($self->{"port_num"}, $ip); | |
1093 | ||
1094 | # Create TCP socket | |
1095 | if (!socket ($self->{"fh"}, PF_INET, SOCK_STREAM, $self->{"proto_num"})) { | |
1096 | croak("tcp socket error - $!"); | |
1097 | } | |
1098 | ||
1099 | if (defined $self->{"local_addr"} && | |
1100 | !CORE::bind($self->{"fh"}, sockaddr_in(0, $self->{"local_addr"}))) { | |
1101 | croak("tcp bind error - $!"); | |
1102 | } | |
1103 | ||
1104 | if ($self->{'device'}) { | |
1105 | setsockopt($self->{"fh"}, SOL_SOCKET, SO_BINDTODEVICE(), pack("Z*", $self->{'device'})) | |
1106 | or croak("error binding to device $self->{'device'} $!"); | |
1107 | } | |
03550e9d JH |
1108 | if ($self->{'tos'}) { |
1109 | setsockopt($self->{"fh"}, SOL_IP, IP_TOS(), pack("I*", $self->{'tos'})) | |
1110 | or croak "error configuring tos to $self->{'tos'} $!"; | |
1111 | } | |
f569508e HS |
1112 | |
1113 | $!=0; | |
1114 | # Try to connect (could take a long time) | |
1115 | connect($self->{"fh"}, $saddr); | |
1116 | # Notify parent of connect error status | |
1117 | my $err = $!+0; | |
1118 | my $wrstr = "$$ $err"; | |
9c36735d JH |
1119 | # Force to 16 chars including \n |
1120 | $wrstr .= " "x(15 - length $wrstr). "\n"; | |
1121 | syswrite($self->{"fork_wr"}, $wrstr, length $wrstr); | |
f569508e HS |
1122 | exit; |
1123 | } | |
1124 | } else { | |
1125 | # fork() failed? | |
1126 | die "fork: $!"; | |
1127 | } | |
1128 | return 1; | |
1129 | } | |
1130 | ||
1131 | # Description: Wait for TCP ACK from host specified | |
1132 | # from ping_syn above. If no host is specified, wait | |
1133 | # for TCP ACK from any of the hosts in the SYN queue. | |
1134 | sub ack | |
1135 | { | |
1136 | my $self = shift; | |
1137 | ||
1138 | if ($self->{"proto"} eq "syn") { | |
1139 | if ($syn_forking) { | |
1140 | my @answer = $self->ack_unfork(shift); | |
1141 | return wantarray ? @answer : $answer[0]; | |
1142 | } | |
1143 | my $wbits = ""; | |
1144 | my $stop_time = 0; | |
1145 | if (my $host = shift) { | |
1146 | # Host passed as arg | |
1147 | if (exists $self->{"bad"}->{$host}) { | |
c94ff782 | 1148 | if (!$self->{"econnrefused"} && |
69c74a9c HS |
1149 | $self->{"bad"}->{ $host } && |
1150 | (($! = ECONNREFUSED)>0) && | |
1151 | $self->{"bad"}->{ $host } eq "$!") { | |
1152 | # "Connection refused" means reachable | |
1153 | # Good, continue | |
1154 | } else { | |
1155 | # ECONNREFUSED means no good | |
1156 | return (); | |
1157 | } | |
f569508e HS |
1158 | } |
1159 | my $host_fd = undef; | |
1160 | foreach my $fd (keys %{ $self->{"syn"} }) { | |
1161 | my $entry = $self->{"syn"}->{$fd}; | |
1162 | if ($entry->[0] eq $host) { | |
1163 | $host_fd = $fd; | |
1164 | $stop_time = $entry->[4] | |
1165 | || croak("Corrupted SYN entry for [$host]"); | |
1166 | last; | |
1167 | } | |
1168 | } | |
1169 | croak("ack called on [$host] without calling ping first!") | |
1170 | unless defined $host_fd; | |
1171 | vec($wbits, $host_fd, 1) = 1; | |
1172 | } else { | |
1173 | # No $host passed so scan all hosts | |
1174 | # Use the latest stop_time | |
1175 | $stop_time = $self->{"stop_time"}; | |
1176 | # Use all the bits | |
1177 | $wbits = $self->{"wbits"}; | |
1178 | } | |
1179 | ||
9c36735d | 1180 | while ($wbits !~ /^\0*\z/) { |
f569508e HS |
1181 | my $timeout = $stop_time - &time(); |
1182 | # Force a minimum of 10 ms timeout. | |
69c74a9c HS |
1183 | $timeout = 0.01 if $timeout <= 0.01; |
1184 | ||
1185 | my $winner_fd = undef; | |
1186 | my $wout = $wbits; | |
1187 | my $fd = 0; | |
1188 | # Do "bad" fds from $wbits first | |
9c36735d | 1189 | while ($wout !~ /^\0*\z/) { |
69c74a9c HS |
1190 | if (vec($wout, $fd, 1)) { |
1191 | # Wipe it from future scanning. | |
1192 | vec($wout, $fd, 1) = 0; | |
1193 | if (my $entry = $self->{"syn"}->{$fd}) { | |
1194 | if ($self->{"bad"}->{ $entry->[0] }) { | |
1195 | $winner_fd = $fd; | |
1196 | last; | |
1197 | } | |
1198 | } | |
1199 | } | |
1200 | $fd++; | |
1201 | } | |
1202 | ||
eb194dd9 | 1203 | if (defined($winner_fd) or my $nfound = mselect(undef, ($wout=$wbits), undef, $timeout)) { |
69c74a9c HS |
1204 | if (defined $winner_fd) { |
1205 | $fd = $winner_fd; | |
1206 | } else { | |
1207 | # Done waiting for one of the ACKs | |
1208 | $fd = 0; | |
1209 | # Determine which one | |
9c36735d | 1210 | while ($wout !~ /^\0*\z/ && |
69c74a9c HS |
1211 | !vec($wout, $fd, 1)) { |
1212 | $fd++; | |
1213 | } | |
f569508e HS |
1214 | } |
1215 | if (my $entry = $self->{"syn"}->{$fd}) { | |
69c74a9c HS |
1216 | # Wipe it from future scanning. |
1217 | delete $self->{"syn"}->{$fd}; | |
1218 | vec($self->{"wbits"}, $fd, 1) = 0; | |
1219 | vec($wbits, $fd, 1) = 0; | |
c94ff782 | 1220 | if (!$self->{"econnrefused"} && |
69c74a9c HS |
1221 | $self->{"bad"}->{ $entry->[0] } && |
1222 | (($! = ECONNREFUSED)>0) && | |
1223 | $self->{"bad"}->{ $entry->[0] } eq "$!") { | |
1224 | # "Connection refused" means reachable | |
1225 | # Good, continue | |
1226 | } elsif (getpeername($entry->[2])) { | |
f569508e | 1227 | # Connection established to remote host |
69c74a9c | 1228 | # Good, continue |
f569508e HS |
1229 | } else { |
1230 | # TCP ACK will never come from this host | |
1231 | # because there was an error connecting. | |
1232 | ||
f569508e HS |
1233 | # This should set $! to the correct error. |
1234 | my $char; | |
9c36735d | 1235 | sysread($entry->[2],$char,1); |
f569508e HS |
1236 | # Store the excuse why the connection failed. |
1237 | $self->{"bad"}->{$entry->[0]} = $!; | |
c94ff782 | 1238 | if (!$self->{"econnrefused"} && |
69c74a9c HS |
1239 | (($! == ECONNREFUSED) || |
1240 | ($! == EAGAIN && $^O =~ /cygwin/i))) { | |
f569508e | 1241 | # "Connection refused" means reachable |
69c74a9c HS |
1242 | # Good, continue |
1243 | } else { | |
1244 | # No good, try the next socket... | |
1245 | next; | |
f569508e | 1246 | } |
f569508e | 1247 | } |
69c74a9c HS |
1248 | # Everything passed okay, return the answer |
1249 | return wantarray ? | |
1250 | ($entry->[0], &time() - $entry->[3], inet_ntoa($entry->[1])) | |
1251 | : $entry->[0]; | |
f569508e HS |
1252 | } else { |
1253 | warn "Corrupted SYN entry: unknown fd [$fd] ready!"; | |
1254 | vec($wbits, $fd, 1) = 0; | |
1255 | vec($self->{"wbits"}, $fd, 1) = 0; | |
1256 | } | |
1257 | } elsif (defined $nfound) { | |
1258 | # Timed out waiting for ACK | |
1259 | foreach my $fd (keys %{ $self->{"syn"} }) { | |
1260 | if (vec($wbits, $fd, 1)) { | |
1261 | my $entry = $self->{"syn"}->{$fd}; | |
1262 | $self->{"bad"}->{$entry->[0]} = "Timed out"; | |
1263 | vec($wbits, $fd, 1) = 0; | |
1264 | vec($self->{"wbits"}, $fd, 1) = 0; | |
1265 | delete $self->{"syn"}->{$fd}; | |
1266 | } | |
1267 | } | |
1268 | } else { | |
1269 | # Weird error occurred with select() | |
1270 | warn("select: $!"); | |
1271 | $self->{"syn"} = {}; | |
1272 | $wbits = ""; | |
1273 | } | |
1274 | } | |
1275 | } | |
1276 | return (); | |
1277 | } | |
1278 | ||
1279 | sub ack_unfork { | |
69c74a9c | 1280 | my ($self,$host) = @_; |
f569508e | 1281 | my $stop_time = $self->{"stop_time"}; |
69c74a9c | 1282 | if ($host) { |
f569508e | 1283 | # Host passed as arg |
69c74a9c HS |
1284 | if (my $entry = $self->{"good"}->{$host}) { |
1285 | delete $self->{"good"}->{$host}; | |
1286 | return ($entry->[0], &time() - $entry->[3], inet_ntoa($entry->[1])); | |
1287 | } | |
f569508e HS |
1288 | } |
1289 | ||
1290 | my $rbits = ""; | |
1291 | my $timeout; | |
69c74a9c | 1292 | |
f569508e HS |
1293 | if (keys %{ $self->{"syn"} }) { |
1294 | # Scan all hosts that are left | |
1295 | vec($rbits, fileno($self->{"fork_rd"}), 1) = 1; | |
1296 | $timeout = $stop_time - &time(); | |
69c74a9c HS |
1297 | # Force a minimum of 10 ms timeout. |
1298 | $timeout = 0.01 if $timeout < 0.01; | |
f569508e HS |
1299 | } else { |
1300 | # No hosts left to wait for | |
1301 | $timeout = 0; | |
1302 | } | |
1303 | ||
1304 | if ($timeout > 0) { | |
69c74a9c HS |
1305 | my $nfound; |
1306 | while ( keys %{ $self->{"syn"} } and | |
eb194dd9 | 1307 | $nfound = mselect((my $rout=$rbits), undef, undef, $timeout)) { |
f569508e | 1308 | # Done waiting for one of the ACKs |
9c36735d | 1309 | if (!sysread($self->{"fork_rd"}, $_, 16)) { |
f569508e HS |
1310 | # Socket closed, which means all children are done. |
1311 | return (); | |
1312 | } | |
1313 | my ($pid, $how) = split; | |
1314 | if ($pid) { | |
1315 | # Flush the zombie | |
1316 | waitpid($pid, 0); | |
1317 | if (my $entry = $self->{"syn"}->{$pid}) { | |
1318 | # Connection attempt to remote host is done | |
1319 | delete $self->{"syn"}->{$pid}; | |
1320 | if (!$how || # If there was no error connecting | |
c94ff782 | 1321 | (!$self->{"econnrefused"} && |
f569508e | 1322 | $how == ECONNREFUSED)) { # "Connection refused" means reachable |
69c74a9c HS |
1323 | if ($host && $entry->[0] ne $host) { |
1324 | # A good connection, but not the host we need. | |
1325 | # Move it from the "syn" hash to the "good" hash. | |
1326 | $self->{"good"}->{$entry->[0]} = $entry; | |
1327 | # And wait for the next winner | |
1328 | next; | |
1329 | } | |
f569508e HS |
1330 | return ($entry->[0], &time() - $entry->[3], inet_ntoa($entry->[1])); |
1331 | } | |
1332 | } else { | |
1333 | # Should never happen | |
1334 | die "Unknown ping from pid [$pid]"; | |
1335 | } | |
1336 | } else { | |
1337 | die "Empty response from status socket?"; | |
1338 | } | |
69c74a9c HS |
1339 | } |
1340 | if (defined $nfound) { | |
f569508e HS |
1341 | # Timed out waiting for ACK status |
1342 | } else { | |
1343 | # Weird error occurred with select() | |
1344 | warn("select: $!"); | |
1345 | } | |
1346 | } | |
1347 | if (my @synners = keys %{ $self->{"syn"} }) { | |
1348 | # Kill all the synners | |
1349 | kill 9, @synners; | |
1350 | foreach my $pid (@synners) { | |
1351 | # Wait for the deaths to finish | |
1352 | # Then flush off the zombie | |
1353 | waitpid($pid, 0); | |
1354 | } | |
1355 | } | |
1356 | $self->{"syn"} = {}; | |
1357 | return (); | |
1358 | } | |
1359 | ||
1360 | # Description: Tell why the ack() failed | |
1361 | sub nack { | |
1362 | my $self = shift; | |
1363 | my $host = shift || croak('Usage> nack($failed_ack_host)'); | |
1364 | return $self->{"bad"}->{$host} || undef; | |
1365 | } | |
1366 | ||
1367 | # Description: Close the connection. | |
a3b93737 RM |
1368 | |
1369 | sub close | |
1370 | { | |
e82f584b | 1371 | my ($self) = @_; |
a3b93737 | 1372 | |
f569508e HS |
1373 | if ($self->{"proto"} eq "syn") { |
1374 | delete $self->{"syn"}; | |
1375 | } elsif ($self->{"proto"} eq "tcp") { | |
1376 | # The connection will already be closed | |
1377 | } else { | |
1378 | $self->{"fh"}->close(); | |
1379 | } | |
a3b93737 RM |
1380 | } |
1381 | ||
af96568d RGS |
1382 | sub port_number { |
1383 | my $self = shift; | |
1384 | if(@_) { | |
1385 | $self->{port_num} = shift @_; | |
1386 | $self->service_check(1); | |
1387 | } | |
1388 | return $self->{port_num}; | |
1389 | } | |
1390 | ||
a3b93737 | 1391 | |
a0d0e21e | 1392 | 1; |
8e07c86e AD |
1393 | __END__ |
1394 | ||
8e07c86e AD |
1395 | =head1 NAME |
1396 | ||
a3b93737 | 1397 | Net::Ping - check a remote host for reachability |
8e07c86e AD |
1398 | |
1399 | =head1 SYNOPSIS | |
1400 | ||
1401 | use Net::Ping; | |
8e07c86e | 1402 | |
a3b93737 RM |
1403 | $p = Net::Ping->new(); |
1404 | print "$host is alive.\n" if $p->ping($host); | |
1405 | $p->close(); | |
1406 | ||
1407 | $p = Net::Ping->new("icmp"); | |
49afa5f6 | 1408 | $p->bind($my_addr); # Specify source interface of pings |
a3b93737 RM |
1409 | foreach $host (@host_array) |
1410 | { | |
1411 | print "$host is "; | |
1412 | print "NOT " unless $p->ping($host, 2); | |
1413 | print "reachable.\n"; | |
1414 | sleep(1); | |
1415 | } | |
1416 | $p->close(); | |
b124990b | 1417 | |
a3b93737 | 1418 | $p = Net::Ping->new("tcp", 2); |
b124990b | 1419 | # Try connecting to the www port instead of the echo port |
af96568d | 1420 | $p->port_number(getservbyname("http", "tcp")); |
a3b93737 RM |
1421 | while ($stop_time > time()) |
1422 | { | |
1423 | print "$host not reachable ", scalar(localtime()), "\n" | |
1424 | unless $p->ping($host); | |
1425 | sleep(300); | |
1426 | } | |
1427 | undef($p); | |
b124990b | 1428 | |
f569508e HS |
1429 | # Like tcp protocol, but with many hosts |
1430 | $p = Net::Ping->new("syn"); | |
af96568d | 1431 | $p->port_number(getservbyname("http", "tcp")); |
f569508e HS |
1432 | foreach $host (@host_array) { |
1433 | $p->ping($host); | |
1434 | } | |
1435 | while (($host,$rtt,$ip) = $p->ack) { | |
1436 | print "HOST: $host [$ip] ACKed in $rtt seconds.\n"; | |
1437 | } | |
1438 | ||
e82f584b JH |
1439 | # High precision syntax (requires Time::HiRes) |
1440 | $p = Net::Ping->new(); | |
1441 | $p->hires(); | |
1442 | ($ret, $duration, $ip) = $p->ping($host, 5.5); | |
1443 | printf("$host [ip: $ip] is alive (packet return time: %.2f ms)\n", 1000 * $duration) | |
1444 | if $ret; | |
1445 | $p->close(); | |
1446 | ||
a3b93737 RM |
1447 | # For backward compatibility |
1448 | print "$host is alive.\n" if pingecho($host); | |
8e07c86e | 1449 | |
a3b93737 | 1450 | =head1 DESCRIPTION |
8e07c86e | 1451 | |
a3b93737 RM |
1452 | This module contains methods to test the reachability of remote |
1453 | hosts on a network. A ping object is first created with optional | |
1454 | parameters, a variable number of hosts may be pinged multiple | |
1455 | times and then the connection is closed. | |
1456 | ||
f569508e HS |
1457 | You may choose one of six different protocols to use for the |
1458 | ping. The "tcp" protocol is the default. Note that a live remote host | |
b124990b | 1459 | may still fail to be pingable by one or more of these protocols. For |
f569508e | 1460 | example, www.microsoft.com is generally alive but not "icmp" pingable. |
787ecdfa | 1461 | |
b124990b JH |
1462 | With the "tcp" protocol the ping() method attempts to establish a |
1463 | connection to the remote host's echo port. If the connection is | |
1464 | successfully established, the remote host is considered reachable. No | |
1465 | data is actually echoed. This protocol does not require any special | |
9c36735d | 1466 | privileges but has higher overhead than the "udp" and "icmp" protocols. |
072620d9 | 1467 | |
b124990b | 1468 | Specifying the "udp" protocol causes the ping() method to send a udp |
a3b93737 RM |
1469 | packet to the remote host's echo port. If the echoed packet is |
1470 | received from the remote host and the received packet contains the | |
1471 | same data as the packet that was sent, the remote host is considered | |
1472 | reachable. This protocol does not require any special privileges. | |
b124990b | 1473 | It should be borne in mind that, for a udp ping, a host |
787ecdfa | 1474 | will be reported as unreachable if it is not running the |
b124990b JH |
1475 | appropriate echo service. For Unix-like systems see L<inetd(8)> |
1476 | for more information. | |
787ecdfa | 1477 | |
b124990b JH |
1478 | If the "icmp" protocol is specified, the ping() method sends an icmp |
1479 | echo message to the remote host, which is what the UNIX ping program | |
1480 | does. If the echoed message is received from the remote host and | |
1481 | the echoed information is correct, the remote host is considered | |
1482 | reachable. Specifying the "icmp" protocol requires that the program | |
1483 | be run as root or that the program be setuid to root. | |
787ecdfa | 1484 | |
b124990b JH |
1485 | If the "external" protocol is specified, the ping() method attempts to |
1486 | use the C<Net::Ping::External> module to ping the remote host. | |
1487 | C<Net::Ping::External> interfaces with your system's default C<ping> | |
1488 | utility to perform the ping, and generally produces relatively | |
787ecdfa JH |
1489 | accurate results. If C<Net::Ping::External> if not installed on your |
1490 | system, specifying the "external" protocol will result in an error. | |
edc5bd88 | 1491 | |
f569508e HS |
1492 | If the "syn" protocol is specified, the ping() method will only |
1493 | send a TCP SYN packet to the remote host then immediately return. | |
1494 | If the syn packet was sent successfully, it will return a true value, | |
1495 | otherwise it will return false. NOTE: Unlike the other protocols, | |
1496 | the return value does NOT determine if the remote host is alive or | |
1497 | not since the full TCP three-way handshake may not have completed | |
1498 | yet. The remote host is only considered reachable if it receives | |
3c4b39be | 1499 | a TCP ACK within the timeout specified. To begin waiting for the |
f569508e HS |
1500 | ACK packets, use the ack() method as explained below. Use the |
1501 | "syn" protocol instead the "tcp" protocol to determine reachability | |
1502 | of multiple destinations simultaneously by sending parallel TCP | |
1503 | SYN packets. It will not block while testing each remote host. | |
1504 | demo/fping is provided in this distribution to demonstrate the | |
1505 | "syn" protocol as an example. | |
1506 | This protocol does not require any special privileges. | |
1507 | ||
a3b93737 RM |
1508 | =head2 Functions |
1509 | ||
1510 | =over 4 | |
1511 | ||
03550e9d | 1512 | =item Net::Ping->new([$proto [, $def_timeout [, $bytes [, $device [, $tos ]]]]]); |
a3b93737 RM |
1513 | |
1514 | Create a new ping object. All of the parameters are optional. $proto | |
1515 | specifies the protocol to use when doing a ping. The current choices | |
f569508e HS |
1516 | are "tcp", "udp", "icmp", "stream", "syn", or "external". |
1517 | The default is "tcp". | |
a3b93737 RM |
1518 | |
1519 | If a default timeout ($def_timeout) in seconds is provided, it is used | |
1520 | when a timeout is not given to the ping() method (below). The timeout | |
1521 | must be greater than 0 and the default, if not specified, is 5 seconds. | |
1522 | ||
1523 | If the number of data bytes ($bytes) is given, that many data bytes | |
1524 | are included in the ping packet sent to the remote host. The number of | |
1525 | data bytes is ignored if the protocol is "tcp". The minimum (and | |
1526 | default) number of data bytes is 1 if the protocol is "udp" and 0 | |
1527 | otherwise. The maximum number of data bytes that can be specified is | |
1528 | 1024. | |
1529 | ||
f569508e | 1530 | If $device is given, this device is used to bind the source endpoint |
3c4b39be | 1531 | before sending the ping packet. I believe this only works with |
f569508e HS |
1532 | superuser privileges and with udp and icmp protocols at this time. |
1533 | ||
3c4b39be | 1534 | If $tos is given, this ToS is configured into the socket. |
03550e9d | 1535 | |
5d20095f JH |
1536 | =item $p->ping($host [, $timeout]); |
1537 | ||
1538 | Ping the remote host and wait for a response. $host can be either the | |
1539 | hostname or the IP number of the remote host. The optional timeout | |
1540 | must be greater than 0 seconds and defaults to whatever was specified | |
1541 | when the ping object was created. Returns a success flag. If the | |
1542 | hostname cannot be found or there is a problem with the IP number, the | |
1543 | success flag returned will be undef. Otherwise, the success flag will | |
1544 | be 1 if the host is reachable and 0 if it is not. For most practical | |
1545 | purposes, undef and 0 and can be treated as the same case. In array | |
f569508e HS |
1546 | context, the elapsed time as well as the string form of the ip the |
1547 | host resolved to are also returned. The elapsed time value will | |
5d20095f JH |
1548 | be a float, as retuned by the Time::HiRes::time() function, if hires() |
1549 | has been previously called, otherwise it is returned as an integer. | |
1550 | ||
15d96390 JH |
1551 | =item $p->source_verify( { 0 | 1 } ); |
1552 | ||
1553 | Allows source endpoint verification to be enabled or disabled. | |
1554 | This is useful for those remote destinations with multiples | |
1555 | interfaces where the response may not originate from the same | |
1556 | endpoint that the original destination endpoint was sent to. | |
5d20095f | 1557 | This only affects udp and icmp protocol pings. |
15d96390 JH |
1558 | |
1559 | This is enabled by default. | |
1560 | ||
c94ff782 | 1561 | =item $p->service_check( { 0 | 1 } ); |
f569508e | 1562 | |
c94ff782 | 1563 | Set whether or not the connect behavior should enforce |
f569508e HS |
1564 | remote service availability as well as reachability. Normally, |
1565 | if the remote server reported ECONNREFUSED, it must have been | |
1566 | reachable because of the status packet that it reported. | |
1567 | With this option enabled, the full three-way tcp handshake | |
1568 | must have been established successfully before it will | |
1569 | claim it is reachable. NOTE: It still does nothing more | |
1570 | than connect and disconnect. It does not speak any protocol | |
1571 | (i.e., HTTP or FTP) to ensure the remote server is sane in | |
1572 | any way. The remote server CPU could be grinding to a halt | |
1573 | and unresponsive to any clients connecting, but if the kernel | |
1574 | throws the ACK packet, it is considered alive anyway. To | |
1575 | really determine if the server is responding well would be | |
1576 | application specific and is beyond the scope of Net::Ping. | |
c94ff782 JH |
1577 | For udp protocol, enabling this option demands that the |
1578 | remote server replies with the same udp data that it was sent | |
1579 | as defined by the udp echo service. | |
f569508e | 1580 | |
c94ff782 | 1581 | This affects the "udp", "tcp", and "syn" protocols. |
f569508e HS |
1582 | |
1583 | This is disabled by default. | |
1584 | ||
c94ff782 JH |
1585 | =item $p->tcp_service_check( { 0 | 1 } ); |
1586 | ||
3c4b39be | 1587 | Deprecated method, but does the same as service_check() method. |
c94ff782 | 1588 | |
e82f584b JH |
1589 | =item $p->hires( { 0 | 1 } ); |
1590 | ||
1591 | Causes this module to use Time::HiRes module, allowing milliseconds | |
1592 | to be returned by subsequent calls to ping(). | |
1593 | ||
15d96390 JH |
1594 | This is disabled by default. |
1595 | ||
49afa5f6 JH |
1596 | =item $p->bind($local_addr); |
1597 | ||
1598 | Sets the source address from which pings will be sent. This must be | |
1599 | the address of one of the interfaces on the local host. $local_addr | |
1600 | may be specified as a hostname or as a text IP address such as | |
1601 | "192.168.1.1". | |
1602 | ||
1603 | If the protocol is set to "tcp", this method may be called any | |
1604 | number of times, and each call to the ping() method (below) will use | |
1605 | the most recent $local_addr. If the protocol is "icmp" or "udp", | |
1606 | then bind() must be called at most once per object, and (if it is | |
1607 | called at all) must be called before the first call to ping() for that | |
1608 | object. | |
1609 | ||
b124990b JH |
1610 | =item $p->open($host); |
1611 | ||
f569508e | 1612 | When you are using the "stream" protocol, this call pre-opens the |
b124990b JH |
1613 | tcp socket. It's only necessary to do this if you want to |
1614 | provide a different timeout when creating the connection, or | |
1615 | remove the overhead of establishing the connection from the | |
1616 | first ping. If you don't call C<open()>, the connection is | |
1617 | automatically opened the first time C<ping()> is called. | |
787ecdfa JH |
1618 | This call simply does nothing if you are using any protocol other |
1619 | than stream. | |
1620 | ||
f569508e HS |
1621 | =item $p->ack( [ $host ] ); |
1622 | ||
1623 | When using the "syn" protocol, use this method to determine | |
1624 | the reachability of the remote host. This method is meant | |
1625 | to be called up to as many times as ping() was called. Each | |
1626 | call returns the host (as passed to ping()) that came back | |
1627 | with the TCP ACK. The order in which the hosts are returned | |
1628 | may not necessarily be the same order in which they were | |
1629 | SYN queued using the ping() method. If the timeout is | |
1630 | reached before the TCP ACK is received, or if the remote | |
1631 | host is not listening on the port attempted, then the TCP | |
1632 | connection will not be established and ack() will return | |
1633 | undef. In list context, the host, the ack time, and the | |
1634 | dotted ip string will be returned instead of just the host. | |
1635 | If the optional $host argument is specified, the return | |
3c4b39be | 1636 | value will be pertaining to that host only. |
f569508e HS |
1637 | This call simply does nothing if you are using any protocol |
1638 | other than syn. | |
1639 | ||
1640 | =item $p->nack( $failed_ack_host ); | |
1641 | ||
1642 | The reason that host $failed_ack_host did not receive a | |
1643 | valid ACK. Useful to find out why when ack( $fail_ack_host ) | |
1644 | returns a false value. | |
1645 | ||
a3b93737 RM |
1646 | =item $p->close(); |
1647 | ||
1648 | Close the network connection for this ping object. The network | |
1649 | connection is also closed by "undef $p". The network connection is | |
1650 | automatically closed if the ping object goes out of scope (e.g. $p is | |
1651 | local to a subroutine and you leave the subroutine). | |
1652 | ||
af96568d RGS |
1653 | =item $p->port_number([$port_number]) |
1654 | ||
1655 | When called with a port number, the port number used to ping is set to | |
1656 | $port_number rather than using the echo port. It also has the effect | |
1657 | of calling C<$p-E<gt>service_check(1)> causing a ping to return a successful | |
1658 | response only if that specific port is accessible. This function returns | |
1659 | the value of the port that C<ping()> will connect to. | |
1660 | ||
a3b93737 RM |
1661 | =item pingecho($host [, $timeout]); |
1662 | ||
1663 | To provide backward compatibility with the previous version of | |
1664 | Net::Ping, a pingecho() subroutine is available with the same | |
1665 | functionality as before. pingecho() uses the tcp protocol. The | |
1666 | return values and parameters are the same as described for the ping() | |
1667 | method. This subroutine is obsolete and may be removed in a future | |
1668 | version of Net::Ping. | |
8e07c86e | 1669 | |
a3b93737 | 1670 | =back |
8e07c86e | 1671 | |
a3b93737 | 1672 | =head1 NOTES |
8e07c86e | 1673 | |
a3b93737 RM |
1674 | There will be less network overhead (and some efficiency in your |
1675 | program) if you specify either the udp or the icmp protocol. The tcp | |
1676 | protocol will generate 2.5 times or more traffic for each ping than | |
1677 | either udp or icmp. If many hosts are pinged frequently, you may wish | |
1678 | to implement a small wait (e.g. 25ms or more) between each ping to | |
1679 | avoid flooding your network with packets. | |
8e07c86e | 1680 | |
a3b93737 | 1681 | The icmp protocol requires that the program be run as root or that it |
787ecdfa JH |
1682 | be setuid to root. The other protocols do not require special |
1683 | privileges, but not all network devices implement tcp or udp echo. | |
8e07c86e | 1684 | |
a3b93737 RM |
1685 | Local hosts should normally respond to pings within milliseconds. |
1686 | However, on a very congested network it may take up to 3 seconds or | |
1687 | longer to receive an echo packet from the remote host. If the timeout | |
1688 | is set too low under these conditions, it will appear that the remote | |
1689 | host is not reachable (which is almost the truth). | |
8e07c86e | 1690 | |
a3b93737 | 1691 | Reachability doesn't necessarily mean that the remote host is actually |
787ecdfa JH |
1692 | functioning beyond its ability to echo packets. tcp is slightly better |
1693 | at indicating the health of a system than icmp because it uses more | |
1694 | of the networking stack to respond. | |
8e07c86e | 1695 | |
a3b93737 RM |
1696 | Because of a lack of anything better, this module uses its own |
1697 | routines to pack and unpack ICMP packets. It would be better for a | |
1698 | separate module to be written which understands all of the different | |
1699 | kinds of ICMP packets. | |
8e07c86e | 1700 | |
5d20095f JH |
1701 | =head1 INSTALL |
1702 | ||
1703 | The latest source tree is available via cvs: | |
1704 | ||
f569508e | 1705 | cvs -z3 -q -d :pserver:anonymous@cvs.roobik.com.:/usr/local/cvsroot/freeware checkout Net-Ping |
5d20095f JH |
1706 | cd Net-Ping |
1707 | ||
1708 | The tarball can be created as follows: | |
1709 | ||
1710 | perl Makefile.PL ; make ; make dist | |
1711 | ||
1712 | The latest Net::Ping release can be found at CPAN: | |
1713 | ||
1714 | $CPAN/modules/by-module/Net/ | |
1715 | ||
1716 | 1) Extract the tarball | |
1717 | ||
1718 | gtar -zxvf Net-Ping-xxxx.tar.gz | |
1719 | cd Net-Ping-xxxx | |
1720 | ||
1721 | 2) Build: | |
1722 | ||
1723 | make realclean | |
1724 | perl Makefile.PL | |
1725 | make | |
1726 | make test | |
1727 | ||
1728 | 3) Install | |
1729 | ||
1730 | make install | |
1731 | ||
1732 | Or install it RPM Style: | |
1733 | ||
1734 | rpm -ta SOURCES/Net-Ping-xxxx.tar.gz | |
1735 | ||
1736 | rpm -ih RPMS/noarch/perl-Net-Ping-xxxx.rpm | |
1737 | ||
c94ff782 JH |
1738 | =head1 BUGS |
1739 | ||
1740 | For a list of known issues, visit: | |
1741 | ||
1742 | https://rt.cpan.org/NoAuth/Bugs.html?Dist=Net-Ping | |
1743 | ||
1744 | To report a new bug, visit: | |
1745 | ||
1746 | https://rt.cpan.org/NoAuth/ReportBug.html?Queue=Net-Ping | |
1747 | ||
49afa5f6 | 1748 | =head1 AUTHORS |
b124990b | 1749 | |
e82f584b | 1750 | Current maintainer: |
49afa5f6 | 1751 | bbb@cpan.org (Rob Brown) |
b124990b | 1752 | |
e82f584b JH |
1753 | External protocol: |
1754 | colinm@cpan.org (Colin McMillen) | |
1755 | ||
b124990b JH |
1756 | Stream protocol: |
1757 | bronson@trestle.com (Scott Bronson) | |
1758 | ||
1759 | Original pingecho(): | |
1760 | karrer@bernina.ethz.ch (Andreas Karrer) | |
1761 | pmarquess@bfsec.bt.co.uk (Paul Marquess) | |
1762 | ||
1763 | Original Net::Ping author: | |
1764 | mose@ns.ccsn.edu (Russell Mosemann) | |
1765 | ||
b124990b JH |
1766 | =head1 COPYRIGHT |
1767 | ||
9c36735d | 1768 | Copyright (c) 2002-2003, Rob Brown. All rights reserved. |
49afa5f6 | 1769 | |
e82f584b | 1770 | Copyright (c) 2001, Colin McMillen. All rights reserved. |
b124990b JH |
1771 | |
1772 | This program is free software; you may redistribute it and/or | |
1773 | modify it under the same terms as Perl itself. | |
1774 | ||
03550e9d | 1775 | $Id: Ping.pm,v 1.86 2003/06/27 21:31:07 rob Exp $ |
c94ff782 | 1776 | |
a3b93737 | 1777 | =cut |