#!/usr/bin/perl
# IBM(c) 2107 EPL license http://www.eclipse.org/legal/epl-v10.html
#(C)IBM Corp
#modified by jbjohnso@us.ibm.com
#This module abstracts the session management aspects of IPMI
package xCAT::IPMI;
use Carp qw/confess cluck/;
BEGIN
{
$::XCATROOT = $ENV{'XCATROOT'} ? $ENV{'XCATROOT'} : '/opt/xcat';
}
use lib "$::XCATROOT/lib/perl";
use strict;
use warnings "all";
use Time::HiRes qw/time/;
use IO::Socket::INET qw/!AF_INET6 !PF_INET6/;
my $initialtimeout=0.5;
use constant STATE_OPENSESSION=>1;
use constant STATE_EXPECTINGRAKP2=>2;
use constant STATE_EXPECTINGRAKP4=>3;
use constant STATE_ESTABLISHED=>4;
use constant STATE_FAILED=>5;
#my $ipmidbg;
#open($ipmidbg,">","/tmp/ipmidbg");
#sub dprint {
# return;
# my $self = shift;
# foreach (@_) {
# foreach (split /\n/,$_) {
# print $ipmidbg $self->{bmc}.": ".$_."\n";
# }
# }
#}
my $doipv6=eval {
require Socket6;
require IO::Socket::INET6;
IO::Socket::INET6->import();
1;
};
use IO::Select;
#use Data::Dumper;
use Digest::MD5 qw/md5/;
my $pendingpackets=0;
my %tabooseq; #TODO: this is a global which means one taboo in the whole set causes unrelated session objects to consider it taboo unnecessarily
my $maxpending; #determined dynamically based on rcvbuf detection
my $ipmi2support;
if ( -f "/etc/debian_release" or -f "/etc/debian_version"){
$ipmi2support = eval {
require Digest::SHA;
Digest::SHA->import(qw/sha1/);
require Digest::HMAC_SHA1;
Digest::HMAC_SHA1->import(qw/hmac_sha1/);
1;
};
}
else {
$ipmi2support = eval {
require Digest::SHA1;
Digest::SHA1->import(qw/sha1/);
require Digest::HMAC_SHA1;
Digest::HMAC_SHA1->import(qw/hmac_sha1/);
1;
};
}
use Crypt::Rijndael;
use Crypt::CBC;
sub hexdump {
foreach (@_) {
printf "%02X ",$_;
}
print "\n";
}
my %payload_types = ( #help readability in certain areas of code by specifying payload by name rather than number
'ipmi' => 0,
'sol' => 1,
'rmcpplusopenreq' => 0x10,
'rmcpplusopenresponse' => 0x11,
'rakp1' => 0x12,
'rakp2' => 0x13,
'rakp3' => 0x14,
'rakp4' => 0x15,
);
my %rmcp_codes = ( #human friendly translations of rmcp+ code numbers
1 => "Insufficient resources to create new session (wait for existing sessions to timeout)",
2 => "Invalid Session ID", #this shouldn't occur...
3 => "Invalid payload type",#shouldn't occur..
4 => "Invalid authentication algorithm", #if this happens, we need to enhance our mechanism for detecting supported auth algorithms
5 => "Invalid integrity algorithm", #same as above
6 => "No matching authentication payload",
7 => "No matching integrity payload",
8 => "Inactive Session ID", #this suggests the session was timed out while trying to negotiate, shouldn't happen
9 => "Invalid role",
0xa => "Unauthorised role or privilege level requested",
0xb => "Insufficient resources to create a session at the requested role",
0xc => "Invalid username length",
0xd => "Unauthorized name",
0xe => "Unauthorized GUID",
0xf => "Invalid integrity check value",
0x10 => "Invalid confidentiality algorithm",
0x11 => "No cipher suite match with proposed security algorithms",
0x12 => "Illegal or unrecognized parameter", #have never observed this, would most likely mean a bug in xCAT or IPMI device
);
my $socket; #global socket for all sessions to share. Fun fun
my $select = IO::Select->new();
our %bmc_handlers; #hash from bmc address to a live session management object.
#only one allowed at a time per bmc
my %sessions_waiting; #track session objects that may want to retry a packet, value is timestamp to 'wake' object for retransmit
sub new {
my $proto = shift;
my $class = ref $proto || $proto;
my $self = {};
bless $self,$class;
my %args = @_;
unless ($ipmi2support) {
$self->{ipmi15only} = 1;
}
$self->{privlevel} = 4;
unless ($args{'bmc'} and defined $args{'userid'} and defined $args{'password'}) {
$self->{error}="bmc, userid, and password must be specified";
return $self;
}
foreach (keys %args) { #store all passed parameters
$self->{$_} = $args{$_};
}
unless ($args{'port'}) { #default to port 623 unless specified
$self->{'port'} = 623;
}
unless ($socket) {
if ($doipv6) {
$socket = IO::Socket::INET6->new(Proto => 'udp');
} else {
$socket = IO::Socket::INET->new(Proto => 'udp');
}
if (-r "/proc/sys/net/core/rmem_max") { # we can detect the maximum allowed socket, read it.
my $sysctl;
open ($sysctl,"<","/proc/sys/net/core/rmem_max");
my $maxrcvbuf=<$sysctl>;
my $rcvbuf = $socket->sockopt(SO_RCVBUF);
if ($maxrcvbuf > $rcvbuf) {
$socket->sockopt(SO_RCVBUF,$maxrcvbuf/2);
}
$maxpending=$maxrcvbuf/1500; #probably could have maxpending go higher, but just go with typical MTU as a guess
} else { #We do not have a way to determine how high we could set RCVBUF, so read the current value and run with it
my $rcvbuf = $socket->sockopt(SO_RCVBUF);
$maxpending=$rcvbuf/1500; #probably could have maxpending go higher, but just go with typical MTU as a guess
}
$select->add($socket);
}
my $bmc_n;
my ($family, $socktype, $protocol, $saddr, $name, $ip, $service);
if ($doipv6) {
($family, $socktype, $protocol, $saddr, $name) = Socket6::getaddrinfo($self->{bmc},623,AF_UNSPEC,SOCK_DGRAM,0);
($ip,$service) = Socket6::getnameinfo($saddr,Socket6::NI_NUMERICHOST());
}
unless ($saddr or $bmc_n = inet_aton($self->{bmc})) {
$self->{error} = "Could not resolve ".$self->{bmc}." to an address";
return $self;
}
if ($ip and $ip =~ /::ffff:\d+\.\d+\.+\d+\.\d+/) {
$ip =~ s/::ffff://;
} elsif (not $ip and $bmc_n) {
$ip = inet_ntoa($bmc_n);
}
$bmc_handlers{$ip}=$self;
if ($saddr) {
$self->{peeraddr} = $saddr;
} else {
$self->{peeraddr} = sockaddr_in($self->{port},$bmc_n);
}
$self->init();
return $self;
}
sub login {
my $self = shift;
my %args = @_;
if ($self->{logged}) {
$args{callback}->("SUCCESS",$args{callback_args});
return;
}
$self->{onlogon} = $args{callback};
$self->{onlogon_args} = $args{callback_args};
$self->{logontries}=5;
$self->get_channel_auth_cap();
}
sub logout {
my $self = shift;
my %args = @_;
$self->{onlogout} = $args{callback};
$self->{onlogout_args} = $args{callback_args};
unless ($self->{logged}) {
if ( $self->{onlogout}) { $self->{onlogout}->("SUCCESS",$self->{onlogout_args}); }
return;
}
$self->{noretry}=1;
$self->subcmd(netfn=>0x6,command=>0x3c,data=>$self->{sessionid},callback=>\&logged_out,callback_args=>$self);
$self->{logged}=0; #seeing as how we are going to take it on faith the logout happened, do the callback now
if ( $self->{onlogout}) {
$self->{onlogout}->("SUCCESS",$self->{onlogout_args});
}
}
sub logged_out {
return;
my $rsp = shift;
my $self = shift;
if (defined $rsp->{code} and $rsp->{code} == 0) {
$self->{logged}=0;
if ( $self->{onlogout}) {
$self->{onlogout}->("SUCCESS",$self->{onlogout_args});
}
} else {
if ( $self->{onlogout}) {
$self->{onlogout}->("ERROR:",$self->{onlogout_args});
}
}
}
sub get_channel_auth_cap { #implement special case for session management command
my $self = shift;
if (defined $self->{ipmi15only}) {
$self->subcmd(netfn=>0x6,command=>0x38,data=>[0x0e,0x04],callback=>\&got_channel_auth_cap,callback_args=>$self);
} else {
$self->subcmd(netfn=>0x6,command=>0x38,data=>[0x8e,0x04],callback=>\&got_channel_auth_cap,callback_args=>$self);
}
#0x8e, set bit to signify recognition of IPMI 2.0 and request channel 'e', current.
#0x04, request administrator privilege
}
sub get_session_challenge {
my $self = shift;
my @user;
if ($self->{userbytes}) {
@user = @{$self->{userbytes}};
} else {
@user = unpack("C*",$self->{userid});
for (my $i=scalar @user;$i<16;$i++) {
$user[$i]=0;
}
$self->{userbytes} = \@user;
}
$self->subcmd(netfn=>0x6,command=>0x39,data=>[2,@user],callback=>\&got_session_challenge,callback_args=>$self); #we only support MD5, we would have errored out if not supported
}
sub got_session_challenge {
my $rsp = shift;
my $self = shift;
my @data = @{$rsp->{data}};
my %localcodes = ( 0x81 => "Invalid user name", 0x82 => "null user disabled" );
my $code = $rsp->{code}; #just to save me some typing
if ($code) {
my $errtxt = sprintf("ERROR: Get challenge failed with %02xh",$code);
if ($localcodes{$code}) {
$errtxt .= " ($localcodes{$code})";
} #TODO: generic codes
$self->{onlogon}->($errtxt, $self->{onlogon_args});
return;
}
$self->{sessionid} = [splice @data,0,4];
$self->{authtype}=2; #switch to auth mode
$self->activate_session(@data);
}
sub activate_session {
my $self = shift;
my @challenge = @_;
my @data = (2,4,@challenge,1,0,0,0);
$self->subcmd(netfn=>0x6,command=>0x3a,data=>\@data,callback=>\&session_activated,callback_args=>$self);
}
sub session_activated {
my $rsp = shift;
my $self = shift;
my $code = $rsp->{code}; #just to save me some typing
my %localcodes = (
0x81 => "No available login slots",
0x82 => "No available login slots for ".$self->{userid},
0x83 => "No slot available as administrator",
0x84 => "Session sequence number out of range",
0x85 => "Invalid session ID",
0x86 => $self->{userid}. " is not allowed to be Administrator or Administrator not allowed over network",
);
if ($code) {
my $errtxt = sprintf("ERROR: Unable to log in to BMC due to code %02xh",$code);
if ($localcodes{$code}) {
$errtxt .= " ($localcodes{$code})";
}
$self->{onlogon}->($errtxt, $self->{onlogon_args});
return;
}
if ($rsp->{error}) {
$self->{onlogon}->($rsp->{error}, $self->{onlogon_args});
return;
}
my @data = @{$rsp->{data}};
$self->{sessionid} = [splice @data,1,4];
$self->{sequencenumber}=$data[1]+($data[2]<<8)+($data[3]<<16)+($data[4]<<24);
$self->{sequencenumberbytes} = [splice @data,1,4];
$self->set_admin_level();
}
sub set_admin_level {
my $self= shift;
$self->subcmd(netfn=>0x6,command=>0x3b,data=>[$self->{privlevel}],callback=>\&admin_level_set,callback_args=>$self);
}
sub admin_level_set {
my $rsp = shift;
my $self = shift;
my %localcodes = (
0x80 => $self->{userid}." is not allowed administrator access",
0x81 => "This user or channel is not allowed administrator access",
0x82 => "Cannot disable User Level authentication",
);
my $code = $rsp->{code};
if ($code) {
my $errtxt = sprintf("ERROR: Failed requesting administrator privilege %02xh",$code);
if ($localcodes{$code}) {
$errtxt .= " (".$localcodes{$code}.")";
}
$self->{onlogon}->($errtxt,$self->{onlogon_args});
} else {
$self->{logged}=1;
$self->{onlogon}->("SUCCESS",$self->{onlogon_args});
}
}
sub got_channel_auth_cap {
my $rsp = shift;
my $self = shift;
if ($rsp->{error}) {
$self->{onlogon}->("ERROR: ".$rsp->{error}, $self->{onlogon_args});
return;
}
my $code = $rsp->{code}; #just to save me some typing
if ($code == 0xcc and not defined $self->{ipmi15only}) { #ok, most likely a stupid ipmi 1.5 bmc
$self->{ipmi15only}=1;
return $self->get_channel_auth_cap();
}
if ($code != 0) {
$self->{onlogon}->("ERROR: Get channel capabilities failed with $code", $self->{onlogon_args});
return;
}
my @data = @{$rsp->{data}};
$self->{currentchannel} = $data[0];
if (($data[1] & 0b10000000) and ($data[3] & 0b10)) {
$self->{ipmiversion} = '2.0';
}
if ($self->{ipmiversion} eq '1.5') {
unless ($data[1] & 0b100) {
$self->{onlogon}->("ERROR: MD5 is required but not enabeld or available on target BMC",$self->{onlogon_args});
}
$self->get_session_challenge();
} elsif ($self->{ipmiversion} eq '2.0') { #do rmcp+
$self->open_rmcpplus_request();
}
}
sub open_rmcpplus_request {
my $self = shift;
$self->{'authtype'}=6;
unless ($self->{localsid}) { $self->{localsid}=358098297; } #this is an arbitrary number of no significance
$self->{localsid}+=1; #new session ID if we are relogging
my @sidbytes = unpack("C4",pack("N",$self->{localsid}));
$self->{sidm} = \@sidbytes;
unless ($self->{rmcptag}) { $self->{rmcptag} = 1; }
$self->{rmcptag}+=1;
my @payload = ($self->{rmcptag},#message tag,
0, #requested privilege role, 0 is highest allowed
0,0, #reserved
@sidbytes,
0,0,0,8,1,0,0,0, #table 13-17, request sha
1,0,0,8,1,0,0,0); #sha integrity
push @payload,(2,0,0,8,1,0,0,0); # aes
$self->{sessionestablishmentcontext} = STATE_OPENSESSION;
$self->sendpayload(payload=>\@payload,type=>$payload_types{'rmcpplusopenreq'});
}
sub checksum {
my $self = shift;
my $sum = 0;
foreach(@_) {
$sum += $_;
}
$sum = ~$sum + 1;
return($sum&0xff);
}
sub subcmd {
my $self = shift;
my %args = @_;
$self->{expectedcmd}=$args{command};
$self->{expectednetfn}=$args{netfn}+1;
my $seqincrement=7;
while ($tabooseq{$self->{expectednetfn}}->{$self->{expectedcmd}}->{$self->{seqlun}} and $seqincrement) { #avoid using a seqlun formerly marked 'taboo', but don't advance by more than 7, just in case
$tabooseq{$self->{expectednetfn}}->{$self->{expectedcmd}}->{$self->{seqlun}}--; #forgive a taboo lun over time...
$self->{seqlun} += 4; #increment by 1<<2
$self->{seqlun} &= 0xff; #make sure we don't get too large a seqlun
$seqincrement--; #assure seq number doesn't go beyond 7 even if it means going taboo, one enhancement would be to pick the *least* taboo instead of just giving up
}
my $rsaddr=0x20; #figrue 13-4, rssa by old code
my @rnl = ($rsaddr,$args{netfn}<<2);
my @rest = ($self->{rqaddr},$self->{seqlun},$args{command},@{$args{data}});
my @payload=(@rnl,$self->checksum(@rnl),@rest,$self->checksum(@rest));
$self->{ipmicallback} = $args{callback};
$self->{ipmicallback_args} = $args{callback_args};
my $type = $payload_types{'ipmi'};
if ($self->{integrityalgo}) {
$type = $type | 0b01000000; #add integrity
}
if ($self->{confalgo}) {
$type = $type | 0b10000000; #add secrecy
}
$self->sendpayload(payload=>\@payload,type=>$type,delayxmit=>$args{delayxmit});
}
sub waitforrsp {
my $self=shift;
my %args=@_;
my $data;
my $peerport;
my $peerhost;
my $timeout; #TODO: code to scan pending objects to find soonest retry deadline
my $curtime=time();
if (defined $args{timeout}) { $timeout = $args{timeout}; }
foreach (keys %sessions_waiting) {
if (defined $timeout and $timeout == 0) { last; } #once we get to zero, then there is no lower and anything else is a waste
if ($sessions_waiting{$_}->{timeout} <= $curtime) {
$timeout=0; #this waitforrsp must go as quickly to retry as possible, but give it a chance this iteration to clear without timedout being called
#if something defferred entry into waitforrsp so long that there was no chance to check for response, this grants at least one shot at getting data
}
if (defined $timeout) {
if ($timeout < $sessions_waiting{$_}->{timeout}-$curtime) {
next;
}
}
$timeout = $sessions_waiting{$_}->{timeout}-$curtime;
}
unless (defined $timeout) {
return scalar (keys %sessions_waiting);
}
if ($select->can_read($timeout)) {
while ($select->can_read(0)) {
my @ipmiq=();
while ($select->can_read(0)) {
$peerport = $socket->recv($data,1500,0);
push @ipmiq,[$peerport,$data];
}
while (@ipmiq) {
my $datagram = shift @ipmiq;
($peerport,$data) = @$datagram;
route_ipmiresponse($peerport,unpack("C*",$data));
while ($select->can_read(0)) {
$peerport = $socket->recv($data,1500,0);
push @ipmiq,[$peerport,$data];
}
}
}
}
foreach (keys %sessions_waiting) { #now that we have given all incoming packets a chance, if some sessions were past due when we entered
#take timeout response action now
if ($sessions_waiting{$_}->{timeout} <= $curtime) {
my $session = $sessions_waiting{$_}->{ipmisession};
delete $sessions_waiting{$_};
$pendingpackets-=1;
$session->timedout();
next;
}
}
return scalar (keys %sessions_waiting);
}
sub timedout {
my $self = shift;
unless (ref $self->{pendingargs}) {
return;
}
$self->{nowait}=1;
$self->{timeout} += 1; #$self->{timeout}*2;
if ($self->{noretry}) { return; }
if ($self->{timeout} > 5) { #giveup, really
$self->{timeout}=$initialtimeout+(0.5*rand());
my $rsp={};
$rsp->{error} = "timeout";
$self->{ipmicallback}->($rsp,$self->{ipmicallback_args});
$self->{nowait}=0;
return;
} elsif ($self->{sessionestablishmentcontext} == STATE_FAILED) {
return;
}
if ($self->{sessionestablishmentcontext} == STATE_OPENSESSION) { #in this particular case, we want to craft a new rmcp session request with a new client side session id, to aid in distinguishing retry from new
$self->open_rmcpplus_request();
#experimintation has showed rakp1 and 3 are best done with a straightforward retry, not something fancy...
#stale rakp3 in a ipmi2 implementation that can't handle it will be detected through rmcp status code rather than assuming we must start over.
} elsif ($self->{sessionestablishmentcontext} == STATE_EXPECTINGRAKP2) { #in this particular case, we want to craft a new rmcp session request with a new client side session id, to aid in distinguishing retry from new
$self->relog();
} elsif ($self->{sessionestablishmentcontext} == STATE_EXPECTINGRAKP4) { #in this particular case, we want to craft a new rmcp session request with a new client side session id, to aid in distinguishing retry from new
$self->relog();
} else {
$self->{hasretried}=1; #remember that we have retried at the moment
$self->sendpayload(%{$self->{pendingargs}},nowait=>1); #do not induce the xmit to wait for packets, just spit it out. timedout is in a wait-for-packets loop already, so it's fine
}
$self->{nowait}=0;
}
sub route_ipmiresponse {
my $sockaddr=shift;
my @rsp = @_;
unless (
$rsp[0] == 0x6 and
$rsp[2] == 0xff and
$rsp[3] == 0x07) {
return; #ignore non-ipmi packets
}
my $host;
my $port;
#($port,$host) = sockaddr_in6($sockaddr);
#$host = inet_ntoa($host);
if ($doipv6) {
($host,$port) = Socket6::getnameinfo($sockaddr,Socket6::NI_NUMERICHOST());
} else {
($port,$host) = sockaddr_in($sockaddr);
$host = inet_ntoa($host);
}
if ($host =~ /::ffff:\d+\.\d+\.+\d+\.\d+/) {
$host =~ s/::ffff://;
}
if ($bmc_handlers{$host}) {
$pendingpackets-=1;
$bmc_handlers{$host}->handle_ipmi_packet(@rsp);
}
}
sub handle_ipmi_packet {
#return zero if we like the response
my $self = shift;
my @rsp = @_;
if ($rsp[4] == 0 or $rsp[4] == 2) { #IPMI 1.5 (check 0 assumption...)
my $remsequencenumber=$rsp[5]+$rsp[6]>>8+$rsp[7]>>16+$rsp[8]>>24;
if ($self->{remotesequencenumber} and $remsequencenumber < $self->{remotesequencenumber} ) {
return 5; #ignore malformed sequence number
}
$self->{remotesequencenumber}=$remsequencenumber;
$self->{remotesequencebytes} = [@rsp[5..8]];
if ($rsp[4] != $self->{authtype}) {
return 2; # not thinking about packets that do not match our preferred auth type
}
unless ($rsp[9] == $self->{sessionid}->[0] and
$rsp[10] == $self->{sessionid}->[1] and
$rsp[11] == $self->{sessionid}->[2] and
$rsp[12] == $self->{sessionid}->[3]) {
return 1; #this response does not match our current session id, ignore it
}
my @authcode=();
if ($rsp[4] == 2) {
@authcode = splice @rsp,13,16;
}
my @payload = splice (@rsp,14,$rsp[13]);
if (@authcode) { #authcode is longer than 0, check it
$self->{checkremotecode}=1;
my @expectedauthcode = $self->ipmi15authcode(@payload);
$self->{checkremotecode}=0;
foreach (0..15) {
if ($expectedauthcode[$_] != $authcode[$_]) {
return 3; #invalid authcode
}
}
}
return $self->parse_ipmi_payload(@payload);
} elsif ($rsp[4] == 6) { #IPMI 2.0
if (($rsp[5]& 0b00111111) == 0x11) {
return $self->got_rmcp_response(splice @rsp,16); #the function always leaves ourselves waiting, no need to deregister
} elsif (($rsp[5]& 0b00111111) == 0x13) {
return $self->got_rakp2(splice @rsp,16); #same as above
} elsif (($rsp[5]& 0b00111111) == 0x15) {
return $self->got_rakp4(splice @rsp,16); #same as above
} elsif (($rsp[5]& 0b00111111) == 0x0) { #ipmi payload, sophisticated logic to follow
my $encrypted;
if ($rsp[5]&0b10000000) {
$encrypted=1;
}
unless ($rsp[5]&0b01000000) {
return 3; #we refuse to examine unauthenticated packets in this context
}
splice (@rsp,0,4); #ditch the rmcp header
my @authcode = splice(@rsp,-12);#strip away authcode and remember it
my @expectedcode = unpack("C*",hmac_sha1(pack("C*",@rsp),$self->{k1}));
splice (@expectedcode,12);
foreach (@expectedcode) {
unless ($_ == shift @authcode) {
return 3; #authcode bad, pretend it never existed
}
}
my $thissid = unpack("N",pack("C*",$rsp[2],$rsp[3],$rsp[4],$rsp[5]));
unless ($thissid==$self->{localsid}) {
return 1; #this response does not match our current session id, ignore it
}
my $remsequencenumber=$rsp[6]+$rsp[7]>>8+$rsp[8]>>16+$rsp[9]>>24;
if ($self->{remotesequencenumber} and $remsequencenumber < $self->{remotesequencenumber} ) {
return 5; #ignore malformed sequence number
}
$self->{remotesequencenumber}=$remsequencenumber;
my $psize = $rsp[10]+($rsp[11]<<8);
my @payload = splice(@rsp,12,$psize);
if ($encrypted) {
my $iv = pack("C*",splice @payload,0,16);
my $cipher = Crypt::CBC->new(-literal_key => 1,-key=>$self->{aeskey},-cipher=>"Crypt::Rijndael",-header=>"none",-iv=>$iv,-keysize=>16,-blocksize=>16,-padding=>\&cbc_pad);
my $crypted = pack("C*",@payload);
@payload = unpack("C*",$cipher->decrypt($crypted));
}
return $self->parse_ipmi_payload(@payload);
} else {
return 6; #unsupported payload
}
} else {
return 7; #unsupported ASF traffic
}
}
sub cbc_pad {
my $block = shift;
my $size = shift;
my $mode = shift;
if ($mode eq 'e') {
my $neededpad=$size-length($block)%$size;
$neededpad -= 1;
my @pad=unpack("C*",$block);
foreach (1..$neededpad) {
push @pad,$_;
}
push @pad,$neededpad;
return pack("C*",@pad);
} elsif ($mode eq 'd') {
my @block = unpack("C*",$block);
my $count = pop @block;
unless ($count) {
return pack("C*",@block);
}
splice @block,0-$count;
return pack("C*",@block);
}
}
sub got_rmcp_response {
my $self = shift;
my @data = @_;
my $byte = shift @data;
unless ($self->{sessionestablishmentcontext} and $self->{sessionestablishmentcontext} != STATE_ESTABLISHED) {
#we would ignore an RMCP+ open session response if we are not in an IPMI2 negotiation, so we have to have *some* state that isn't established for this to be kosher
return 9; #now's not the time for this response, ignore it
}
unless ($byte == $self->{rmcptag}) { #make sure this rmcp response is specifically the last one we sent.... we don't want to happily proceed with the risk a retry request blew up our temp session id without letting us know
return 9;
}
$byte = shift @data;
unless ($byte == 0x00) {
if ($rmcp_codes{$byte}) {
$self->{onlogon}->("ERROR: ".$rmcp_codes{$byte},$self->{onlogon_args}); #TODO: errors
} else {
$self->{onlogon}->("ERROR: $byte code on opening RMCP+ session",$self->{onlogon_args}); #TODO: errors
}
return 9;
}
$byte = shift @data;
unless ($byte >= 4) {
$self->{onlogon}->("ERROR: Cannot acquire sufficient privilege",$self->{onlogon_args});
return 9;
}
splice @data,0,5;
$self->{pendingsessionid} = [splice @data,0,4];
#TODO: if we retried, and the first answer comes back but the second answer is dropped, log in will fail as we do not know our correct session id
#basically, we would have to retry open session requested until RAKP2 *confirmed* good
$self->send_rakp1();
return 0;
}
sub send_rakp3 {
#TODO: this is the point where OPEN RMCP SESSION REQUEST should have retry stopped, not send_rakp1
my $self = shift;
$self->{rmcptag}+=1;
my @payload = ($self->{rmcptag},0,0,0,@{$self->{pendingsessionid}});
my @user = unpack("C*",$self->{userid});
push @payload,unpack("C*",hmac_sha1(pack("C*",@{$self->{remoterandomnumber}},@{$self->{sidm}},$self->{privlevel},scalar @user,@user),$self->{password}));
$self->sendpayload(payload=>\@payload,type=>$payload_types{'rakp3'});
}
sub send_rakp1 {
my $self = shift;
$self->{rmcptag}+=1;
my @payload = ($self->{rmcptag},0,0,0,@{$self->{pendingsessionid}});
$self->{randomnumber}=[];
foreach (1..16) {
my $randomnumber = int(rand(255));
push @{$self->{randomnumber}},$randomnumber;
}
push @payload, @{$self->{randomnumber}};
push @payload,($self->{privlevel},0,0); # request priv
my @user = unpack("C*",$self->{userid});
push @payload,scalar @user;
push @payload,@user;
$self->{sessionestablishmentcontext} = STATE_EXPECTINGRAKP2;
$self->sendpayload(payload=>\@payload,type=>$payload_types{'rakp1'});
}
sub init {
my $self = shift;
$self->{sessionestablishmentcontext} = 0;
$self->{'sequencenumber'} = 0; #init sequence number
$self->{'sequencenumberbytes'} = [0,0,0,0]; #init sequence number
$self->{'sessionid'} = [0,0,0,0]; # init session id
$self->{'authtype'}=0; # first messages will have auth type of 0
$self->{'ipmiversion'}='1.5'; # send first packet as 1.5
$self->{'timeout'}=$initialtimeout+(0.5*rand()); #start at a quick timeout, increase on retry
$self->{'seqlun'}=0; #the IPMB seqlun combo, increment by 4s
$self->{rqaddr}=0x81; #Per table '5-4' system sofware ids in the ipmi spec, we are allowed 0x81-0x8d software ids
#A problem with ipmi is that chatty commands (rinv) can mistake stale data for new if sequence number overflows
#for example, if 'get firmware information' command is retried, and happens to have sequence number 4,
#64 transactions later a reply to the retry comes up, the data is passed into the callback function because of ambiguity introduced by the
#overflowed sequence number
#to mitigate this, we will iterate rqaddr every time the seqlun counter overflows
#of course, this still means that rqaddr will, itself, overflow, but it mitigates things because:
#448 instead of 64 transactions are now required before ambiguity is possible
#A stale reply has to come in after the conversation has advanced at least 448 transactions, meaning longer delay on extraneous reply before this is a problem
#even if a stale reply comes in at *about* the right time, it has to match an exact multiple of 448 instead of 64, which is significantly less likely.
#I abandoned this strategy, but leaving it documented for posterity. The issue is that some operations don't like the client changing software id
#midstream (notably SDR reservations).
#ipmi spec does contain some guidance in the BT section of the spec 'Using the Seq Field'. There is guidance elsewhere about sequence numbers higher than 8 beyond current
#but I'm not sure if thet means 'session sequence number' or 'seq', which are very very different.
#one tangible recommendation is for the combination of command+seq+netfn to be unique, which can certainly help, so we should track netfn and command to make sure response
#matches at least the expected command and netfn.
#additionally, it looks like we could implement a sort of 'taboo' sequence number scheme. When we ascertain that we are retrying, we flag the current sequence number to be
#'taboo' in the future. When the time comes to increment sequence number, we mark the current combination of command+netfn+seq as 'taboo'
#should circumstances suggest that we are about to transmit a packet with a taboo combination, we bump sequence number until no longer taboo, no more than 8 bumps.
#if we should incur 7 bumps, clear the taboo list and continue on, hoping for best (pessimistically assuming the spec means seq number or that someone could at least interpret it that way)
#I'll implement this later...
$self->{'logged'}=0;
}
sub relog {
my $self=shift;
$self->init();
$self->{logontries} -= 1;
$self->get_channel_auth_cap();
}
sub got_rakp4 {
my $self = shift;
my @data = @_;
my $byte = shift @data;
unless ($self->{sessionestablishmentcontext} == STATE_EXPECTINGRAKP4) { #ignore rakp4 unless we are explicitly expecting RAKP4
return 9; #now's not the time for this response, ignore it
}
unless ($byte == $self->{rmcptag}) { #make sure this rmcp response is specifically the last one we sent.... we don't want to happily proceed with the risk a retry request blew up our temp session id without letting us know
return 9;
}
$byte = shift @data;
unless ($byte == 0x00) {
if (($byte == 0x02) and $self->{logontries}) {
#ok, turns out an IPMI2 device may optimistically assume that since it has transmitted RAKP4, it's done with this whole RAKP exchange, thus
#code 2 can happen.... To workaround this, code 2 is taken as a cue to start over if we haven't got an rakp2 yet
$self->relog();
}
if (($byte == 0x02 or $byte == 15) and $self->{logontries}) { # most likely scenario is that a retry earlier in the process invalided the flow this packet came in on, ignore it and hope the retries all sort out
#UPDATE: turns out open rmcp session request shenanigans were to blame, rakp2 straight retransmits seems safe
#the biggest risk: that we did not receive the correct rakp2, so the prudent thing to be doing in this time interval would be retrying RAKP1...
#ipmi2 session negotiation is a bit weird in how retries can corrupt state and we effectively should be rewinding a bit...
#TODO: think about retry logic hard to decide how many packets we can retry
#thought: can we match a failed RAKP2 to the last RAKP1 we transmitted? If we can, and we see the last RAKP1 was in fact the one this response is for, that
#would definitely mean we should rewinnd to open session rquest..
#ditto for rakp4, if we can confirm rakp is for the last transmitted rakp3, then we need to rewind to send_rakp1...
#$self->relog();
return;
}
if ($rmcp_codes{$byte}) {
$self->{onlogon}->("ERROR: ".$rmcp_codes{$byte},$self->{onlogon_args}); #TODO: errors
} else {
$self->{onlogon}->("ERROR: $byte code on opening RMCP+ session",$self->{onlogon_args}); #TODO: errors
}
return 9;
}
splice @data,0,6; #discard reserved bytes and session id
my @expectauthcode = unpack("C*",hmac_sha1(pack("C*",@{$self->{randomnumber}},@{$self->{pendingsessionid}},@{$self->{remoteguid}}),$self->{sik}));
foreach (@expectauthcode[0..11]) {
unless ($_ == (shift @data)) {
#we'll just ignore this transgression...... *this time*
#$self->{onlogon}->("ERROR: failure in final rakp exchange message",$self->{onlogon_args});
return 9;
}
}
$self->{sessionid} = $self->{pendingsessionid};
$self->{integrityalgo}='sha1';
$self->{confalgo} = 'aes';
$self->{sequencenumber}=1;
$self->{sequencenumberbytes}=[1,0,0,0];
$self->{sessionestablishmentcontext} = STATE_ESTABLISHED; #will move on to relying upon session sequence number
$self->set_admin_level();
return 0;
}
sub got_rakp2 {
my $self=shift;
my @data = @_;
my $byte = shift @data;
unless ($self->{sessionestablishmentcontext} >= STATE_EXPECTINGRAKP2 and $self->{sessionestablishmentcontext} != STATE_ESTABLISHED) {
#we will bail out unless the state is either EXPECTINGRAKP2 or EXPECTINGRAKP4.
#the reason being that if an old rakp1 retry actually made it and we were just too aggressive, then a previous rakp2 is invalidated and invalid session id or the integrity check value is bad
return 9; #now's not the time for this response, ignore it
}
unless ($byte == $self->{rmcptag}) { #make sure this rmcp response is specifically the last one we sent.... we don't want to happily proceed with the risk a retry request blew up our temp session id without letting us know
return 9;
}
$byte = shift @data;
unless ($byte == 0x00) {
if ($byte == 0x9 and $self->{privlevel} == 4) {
# this is probably an environment that wants to give us only operator
# try to connect again at 3.
$self->{privlevel} = 3;
$self->relog();
return;
}
if ($byte == 0x02) { #invalid session id is almost certainly because a retry on rmcp+ open session response rendered our session id invalid, ignore this in the hope that we'll get an answer for our retry that invalidated us..
#$self->relog();
#TODO: probably should disable RAKP1 retry here... high likelihood that we'll just spew a bad RAKP1 and Open Session Request retry would be more appropriate to try to discern a valid session id
return;
}
if ($rmcp_codes{$byte}) {
$self->{onlogon}->("ERROR: ".$rmcp_codes{$byte},$self->{onlogon_args}); #TODO: errors
} else {
$self->{onlogon}->("ERROR: $byte code on opening RMCP+ session",$self->{onlogon_args}); #TODO: errors
}
return 9;
}
splice @data,0,6; # throw away reserved bytes, and session id, might need to check
$self->{remoterandomnumber} = [];
foreach (1..16) {
push @{$self->{remoterandomnumber}},(shift @data);
}
$self->{remoteguid} = [];
foreach (1..16) {
push @{$self->{remoteguid}},(shift @data);
}
#Data now represents authcode.. sha1 only..
my @user = unpack("C*",$self->{userid});
my $ulength = scalar @user;
my $hmacdata = pack("C*",(@{$self->{sidm}},@{$self->{pendingsessionid}},@{$self->{randomnumber}},@{$self->{remoterandomnumber}},@{$self->{remoteguid}},$self->{privlevel},$ulength,@user));
my @expectedhash = (unpack("C*",hmac_sha1($hmacdata,$self->{password})));
foreach (0..(scalar(@expectedhash)-1)) {
if ($expectedhash[$_] != $data[$_]) {
$self->{sessionestablishmentcontext}=STATE_FAILED;
$self->{onlogon}->("ERROR: Incorrect password provided",$self->{onlogon_args});
return 9;
}
}
$self->{sik} = hmac_sha1(pack("C*",@{$self->{randomnumber}},@{$self->{remoterandomnumber}},$self->{privlevel},$ulength,@user),$self->{password});
$self->{k1} = hmac_sha1(pack("C*",1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1),$self->{sik});
$self->{k2} = hmac_sha1(pack("C*",2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2),$self->{sik});
my @aeskey = unpack("C*",$self->{k2});
$self->{aeskey} = pack("C*",(splice @aeskey,0,16));
$self->{sessionestablishmentcontext} = STATE_EXPECTINGRAKP4;
$self->send_rakp3();
return 0;
}
sub parse_ipmi_payload {
my $self=shift;
my @payload = @_;
#for now, just trash the headers, this has been validated to death anyway
#except seqlun, that one is important
unless ($payload[4] == $self->{seqlun} and $payload[1]>>2 == $self->{expectednetfn} and $payload[5] == $self->{expectedcmd} ) {
#both sequence number and arqaddr must match, because we are using rqaddr to extend the sequence number
#print "Successfully didn't get confused by stale response ".$payload[4]." and ".($self->{seqlun}-4)."\n";
#hexdump(@payload);
return 1; #response mismatch
}
if ($self->{hasretried}) { #if we sent this out multiple times, mark the sequence as taboo
$self->{hasretried}=0;
$tabooseq{$self->{expectednetfn}}->{$self->{expectedcmd}}->{$self->{seqlun}}=16; #consider a lun taboo for 16 overflow cycles
}
#set to impossible values to reflect the fact we expect *no* command/nnetfn at the moment
$self->{expectednetfn}=0x1ff;
$self->{expectedcmd}=0x1ff;
$self->{seqlun} += 4; #increment by 1<<2
if ($self->{seqlun} > 0xff) { #overflow case
#Problem with rqaddr iteration strategy to get more sequence numbers, changing swid invalidates reservation ids for some BMCs...
# if ($self->{rqaddr} == 0x8d) { #rqaddr itself is forced to overflow
# $self->{rqaddr}=0x81;
# } else {
# $self->{rqaddr}+=2; #table 5-4 demands rqaddr be odd for software ids, so we must increment by 2
#}
$self->{seqlun} &= 0xff; #keep it one byte
}
delete $sessions_waiting{$self}; #deregister self as satisfied, callback will reregister if appropriate
delete $self->{pendingargs};
splice @payload,0,5; #remove rsaddr/netfs/lun/checksum/rq/seq/lun
pop @payload; #remove checksum
my $rsp;
$rsp->{cmd} = shift @payload;
$rsp->{code} = shift @payload;
$rsp->{data} = \@payload;
$self->{timeout}=$initialtimeout+(0.5*rand());
$self->{ipmicallback}->($rsp,$self->{ipmicallback_args});
return 0;
}
sub ipmi15authcode {
my $self = shift;
#per table 22-22 'authcode algorithms'
my @data = @_;
my @password;
my @code;
if ($self->{passbytes}) {
@password = @{$self->{passbytes}};
} else {
@password = unpack("C*",$self->{password});
for (my $i=scalar @password;$i<16;$i++) {
$password[$i]=0;
}
$self->{passbytes} = \@password;
}
my @sequencebytes = @{$self->{sequencenumberbytes}};
if ($self->{checkremotecode}) {
@sequencebytes = @{$self->{remotesequencebytes}};
}
if ($self->{authtype} == 0) {
return ();
} elsif ($self->{authtype} == 2) {
return unpack("C*",md5(pack("C*",@password,@{$self->{sessionid}},@data,@sequencebytes,@password))); #ignoring single-session channels
}
#Not supporting plaintext passwords, that would be asinine
}
#this function accepts a generic ipmi command and applies current session data and handles the 1.5<->2.0 differences
sub sendpayload {
#implementation used section 13.6, examle ipmi over lan packet
my $self = shift;
my %args = @_;
my @msg = (0x6,0x0,0xff,0x07); #RMCP header is constant in IPMI
my $type = $args{type} & 0b00111111;
my @payload = @{$args{payload}};
$self->{pendingargs} = \%args;
push @msg,$self->{'authtype'}; # add authtype byte (will support 0 only for session establishment, 2 for ipmi 1.5, 6 for ipmi2
if ($self->{'ipmiversion'} eq '2.0') { #TODO: revisit this to see if assembly makes sense
push @msg, $args{type};
if ($type == 2) {
push @msg,@{$self->{'iana'}},0;
push @msg,@{$self->{'oem_payload_id'}};
}
push @msg,@{$self->{sessionid}};
}
push @msg,@{$self->{sequencenumberbytes}};
if ($self->{'ipmiversion'} eq '1.5') { #ipmi 2.0 for some reason swapped session id and seq number location
push @msg,@{$self->{sessionid}};
unless ($self->{authtype} == 0) {
push @msg,$self->ipmi15authcode(@payload);
}
push @msg,scalar(@payload);
push @msg,@payload;
#TODO: sweat a pad or not? spec isn't crystal clear on the 'legacy pad' and it sounds like it is just for some old crappy nics that have no business in a good server
} elsif ($self->{'ipmiversion'} eq '2.0') {
#TODO:
my $size = scalar(@payload);
if ($self->{confalgo}) {
my $pad = ($size+1)%16;
if ($pad) { $pad = 16-$pad; }
my $newsize =$size+$pad+17;
push @msg,($newsize&0xff,$newsize>>8);
my @iv;
foreach (1..16) { #generate a new iv for outbound packet
my $num = int(rand(255));
push @msg,$num;
push @iv, $num;
}
my $cipher = Crypt::CBC->new(-literal_key => 1,-key=>$self->{aeskey},-cipher=>"Rijndael",-header=>"none",-iv=>pack("C*",@iv),-keysize=>16,-padding=>\&cbc_pad);
push @msg,(unpack("C*",$cipher->encrypt(pack("C*",@payload))));
} else {
push @msg,($size&0xff,$size>>8);
push @msg,@payload;
}
if ($self->{integrityalgo}) {
my @integdata = @msg[4..(scalar @msg)-1];
my $neededpad=((scalar @integdata)+2)%4;
if ($neededpad) { $neededpad = 4-$neededpad; }
for (my $i=0;$i<$neededpad;$i++) {
push @integdata,0xff;
push @msg,0xff;
}
push @msg,$neededpad;
push @integdata,$neededpad;
push @msg,7;
push @integdata,7;
my $intdata = pack("C*",@integdata);
my @acode = unpack("C*",hmac_sha1($intdata,$self->{k1}));
push @msg,splice @acode,0,12;
#push integrity pad
#push @msg,0x7; #reserved byte in 2.0
#push integrity data
}
}
unless ($args{nowait} or $self->{nowait}) { #if nowait indicated, the packet will be sent regardless of maxpending
#primary use case would be retries that should represent no delta to pending sessions in aggregate and therefore couldn't exceed maxpending anywy
#if we did do this on timedout, waitforrsp may recurse, which is a complicated issue. Theoretically, if waitforrsp protected itself, it
#would act the same, but best be explicit about nowait if practice does not match theory
#another scenario is if we have urgent payload for a BMC (PET acknowledge, negotiating login if temp session id is very short lived
$self->waitforrsp(timeout=>0); #the intent here is to interrupt outgoing activity to give a chance to respond to incoming data
#until we send, the ball is in our court so things are less time critical
while ($pendingpackets > $maxpending) { #if we hit our ceiling, wait until a slot frees up, which can't happen until either a packet is received or someone gives up
$self->waitforrsp();
}
}
$socket->send(pack("C*",@msg),0,$self->{peeraddr});
$sessions_waiting{$self}={};
$sessions_waiting{$self}->{ipmisession}=$self;
if ($args{delayxmit}) {
$sessions_waiting{$self}->{timeout}=time()+$args{delayxmit};
$self->{timeout}=($initialtimeout+(0.5*rand()))/2; #since we are burning one of the retry attempts, start the backoff algorithm faster to make it come out even
undef $args{delayxmit};
return; #don't actually transmit packet, use retry timer to start us off
} else {
$sessions_waiting{$self}->{timeout}=time()+$self->{timeout};
}
$pendingpackets+=1;
if ($self->{sequencenumber}) { #if using non-zero, increment, otherwise..
$self->{sequencenumber} += 1;
$self->{sequencenumberbytes} = [$self->{sequencenumber}&0xff,($self->{sequencenumber}>>8)&0xff,($self->{sequencenumber}>>16)&0xff,($self->{sequencenumber}>>24)&0xff];
}
}
1;