# sha256.tcl - Copyright (C) 2005 Pat Thoyts <[email protected]>
#
# SHA1 defined by FIPS 180-2, "The Secure Hash Standard"
# HMAC defined by RFC 2104, "Keyed-Hashing for Message Authentication"
#
# This is an implementation of the secure hash algorithms specified in the
# FIPS 180-2 document.
#
# This implementation permits incremental updating of the hash and
# provides support for external compiled implementations using critcl.
#
# This implementation permits incremental updating of the hash and
# provides support for external compiled implementations either using
# critcl (sha256c).
#
# Ref: http://csrc.nist.gov/publications/fips/fips180-2/fips180-2.pdf
# http://csrc.nist.gov/publications/fips/fips180-2/fips180-2withchangenotice.pdf
#
# -------------------------------------------------------------------------
# See the file "license.terms" for information on usage and redistribution
# of this file, and for a DISCLAIMER OF ALL WARRANTIES.
# -------------------------------------------------------------------------
# @mdgen EXCLUDE: sha256c.tcl
package require Tcl 8.2; # tcl minimum version
namespace eval ::sha2 {
variable accel
array set accel {tcl 0 critcl 0}
variable loaded {}
namespace export sha256 hmac \
SHA256Init SHA256Update SHA256Final
variable uid
if {![info exists uid]} {
set uid 0
}
variable K
if {![info exists K]} {
# FIPS 180-2: 4.2.2 SHA-256 constants
set K [list \
0x428a2f98 0x71374491 0xb5c0fbcf 0xe9b5dba5 \
0x3956c25b 0x59f111f1 0x923f82a4 0xab1c5ed5 \
0xd807aa98 0x12835b01 0x243185be 0x550c7dc3 \
0x72be5d74 0x80deb1fe 0x9bdc06a7 0xc19bf174 \
0xe49b69c1 0xefbe4786 0x0fc19dc6 0x240ca1cc \
0x2de92c6f 0x4a7484aa 0x5cb0a9dc 0x76f988da \
0x983e5152 0xa831c66d 0xb00327c8 0xbf597fc7 \
0xc6e00bf3 0xd5a79147 0x06ca6351 0x14292967 \
0x27b70a85 0x2e1b2138 0x4d2c6dfc 0x53380d13 \
0x650a7354 0x766a0abb 0x81c2c92e 0x92722c85 \
0xa2bfe8a1 0xa81a664b 0xc24b8b70 0xc76c51a3 \
0xd192e819 0xd6990624 0xf40e3585 0x106aa070 \
0x19a4c116 0x1e376c08 0x2748774c 0x34b0bcb5 \
0x391c0cb3 0x4ed8aa4a 0x5b9cca4f 0x682e6ff3 \
0x748f82ee 0x78a5636f 0x84c87814 0x8cc70208 \
0x90befffa 0xa4506ceb 0xbef9a3f7 0xc67178f2 \
]
}
}
# -------------------------------------------------------------------------
# Management of sha256 implementations.
# LoadAccelerator --
#
# This package can make use of a number of compiled extensions to
# accelerate the digest computation. This procedure manages the
# use of these extensions within the package. During normal usage
# this should not be called, but the test package manipulates the
# list of enabled accelerators.
#
proc ::sha2::LoadAccelerator {name} {
variable accel
set r 0
switch -exact -- $name {
tcl {
# Already present (this file)
set r 1
}
critcl {
if {![catch {package require tcllibc}]
|| ![catch {package require sha256c}]} {
set r [expr {[info commands ::sha2::sha256c_update] != {}}]
}
}
default {
return -code error "invalid accelerator $key:\
must be one of [join [KnownImplementations] {, }]"
}
}
set accel($name) $r
return $r
}
# ::sha2::Implementations --
#
# Determines which implementations are
# present, i.e. loaded.
#
# Arguments:
# None.
#
# Results:
# A list of implementation keys.
proc ::sha2::Implementations {} {
variable accel
set res {}
foreach n [array names accel] {
if {!$accel($n)} continue
lappend res $n
}
return $res
}
# ::sha2::KnownImplementations --
#
# Determines which implementations are known
# as possible implementations.
#
# Arguments:
# None.
#
# Results:
# A list of implementation keys. In the order
# of preference, most prefered first.
proc ::sha2::KnownImplementations {} {
return {critcl tcl}
}
proc ::sha2::Names {} {
return {
critcl {tcllibc based}
tcl {pure Tcl}
}
}
# ::sha2::SwitchTo --
#
# Activates a loaded named implementation.
#
# Arguments:
# key Name of the implementation to activate.
#
# Results:
# None.
proc ::sha2::SwitchTo {key} {
variable accel
variable loaded
if {[string equal $key $loaded]} {
# No change, nothing to do.
return
} elseif {![string equal $key ""]} {
# Validate the target implementation of the switch.
if {![info exists accel($key)]} {
return -code error "Unable to activate unknown implementation \"$key\""
} elseif {![info exists accel($key)] || !$accel($key)} {
return -code error "Unable to activate missing implementation \"$key\""
}
}
# Deactivate the previous implementation, if there was any.
if {![string equal $loaded ""]} {
foreach c {
SHA256Init SHA224Init
SHA256Final SHA224Final
SHA256Update
} {
rename ::sha2::$c ::sha2::${c}-${loaded}
}
}
# Activate the new implementation, if there is any.
if {![string equal $key ""]} {
foreach c {
SHA256Init SHA224Init
SHA256Final SHA224Final
SHA256Update
} {
rename ::sha2::${c}-${key} ::sha2::$c
}
}
# Remember the active implementation, for deactivation by future
# switches.
set loaded $key
return
}
# -------------------------------------------------------------------------
# SHA256Init --
#
# Create and initialize an SHA256 state variable. This will be
# cleaned up when we call SHA256Final
#
proc ::sha2::SHA256Init-tcl {} {
variable uid
set token [namespace current]::[incr uid]
upvar #0 $token tok
# FIPS 180-2: 5.3.2 Setting the initial hash value
array set tok \
[list \
A [expr {int(0x6a09e667)}] \
B [expr {int(0xbb67ae85)}] \
C [expr {int(0x3c6ef372)}] \
D [expr {int(0xa54ff53a)}] \
E [expr {int(0x510e527f)}] \
F [expr {int(0x9b05688c)}] \
G [expr {int(0x1f83d9ab)}] \
H [expr {int(0x5be0cd19)}] \
n 0 i "" v 256]
return $token
}
proc ::sha2::SHA256Init-critcl {} {
variable uid
set token [namespace current]::[incr uid]
upvar #0 $token tok
# FIPS 180-2: 5.3.2 Setting the initial hash value
set tok(sha256c) [sha256c_init256]
return $token
}
# SHA256Update --
#
# This is called to add more data into the hash. You may call this
# as many times as you require. Note that passing in "ABC" is equivalent
# to passing these letters in as separate calls -- hence this proc
# permits hashing of chunked data
#
# If we have a C-based implementation available, then we will use
# it here in preference to the pure-Tcl implementation.
#
proc ::sha2::SHA256Update-tcl {token data} {
upvar #0 $token state
# Update the state values
incr state(n) [string length $data]
append state(i) $data
# Calculate the hash for any complete blocks
set len [string length $state(i)]
for {set n 0} {($n + 64) <= $len} {} {
SHA256Transform $token [string range $state(i) $n [incr n 64]]
}
# Adjust the state for the blocks completed.
set state(i) [string range $state(i) $n end]
return
}
proc ::sha2::SHA256Update-critcl {token data} {
upvar #0 $token state
set state(sha256c) [sha256c_update $data $state(sha256c)]
return
}
# SHA256Final --
#
# This procedure is used to close the current hash and returns the
# hash data. Once this procedure has been called the hash context
# is freed and cannot be used again.
#
# Note that the output is 256 bits represented as binary data.
#
proc ::sha2::SHA256Final-tcl {token} {
upvar #0 $token state
SHA256Penultimate $token
# Output
set r [bytes $state(A)][bytes $state(B)][bytes $state(C)][bytes $state(D)][bytes $state(E)][bytes $state(F)][bytes $state(G)][bytes $state(H)]
unset state
return $r
}
proc ::sha2::SHA256Final-critcl {token} {
upvar #0 $token state
set r $state(sha256c)
unset state
return $r
}
# SHA256Penultimate --
#
#
proc ::sha2::SHA256Penultimate {token} {
upvar #0 $token state
# FIPS 180-2: 5.1.1: Padding the message
#
set len [string length $state(i)]
set pad [expr {56 - ($len % 64)}]
if {$len % 64 > 56} {
incr pad 64
}
if {$pad == 0} {
incr pad 64
}
append state(i) [binary format a$pad \x80]
# Append length in bits as big-endian wide int.
set dlen [expr {8 * $state(n)}]
append state(i) [binary format II 0 $dlen]
# Calculate the hash for the remaining block.
set len [string length $state(i)]
for {set n 0} {($n + 64) <= $len} {} {
SHA256Transform $token [string range $state(i) $n [incr n 64]]
}
}
# -------------------------------------------------------------------------
proc ::sha2::SHA224Init-tcl {} {
variable uid
set token [namespace current]::[incr uid]
upvar #0 $token tok
# FIPS 180-2 (change notice 1) (1): SHA-224 initialization values
array set tok \
[list \
A [expr {int(0xc1059ed8)}] \
B [expr {int(0x367cd507)}] \
C [expr {int(0x3070dd17)}] \
D [expr {int(0xf70e5939)}] \
E [expr {int(0xffc00b31)}] \
F [expr {int(0x68581511)}] \
G [expr {int(0x64f98fa7)}] \
H [expr {int(0xbefa4fa4)}] \
n 0 i "" v 224]
return $token
}
proc ::sha2::SHA224Init-critcl {} {
variable uid
set token [namespace current]::[incr uid]
upvar #0 $token tok
# FIPS 180-2 (change notice 1) (1): SHA-224 initialization values
set tok(sha256c) [sha256c_init224]
return $token
}
interp alias {} ::sha2::SHA224Update {} ::sha2::SHA256Update
proc ::sha2::SHA224Final-tcl {token} {
upvar #0 $token state
SHA256Penultimate $token
# Output
set r [bytes $state(A)][bytes $state(B)][bytes $state(C)][bytes $state(D)][bytes $state(E)][bytes $state(F)][bytes $state(G)]
unset state
return $r
}
proc ::sha2::SHA224Final-critcl {token} {
upvar #0 $token state
# Trim result down to 224 bits (by 4 bytes).
# See output below, A..G, not A..H
set r [string range $state(sha256c) 0 end-4]
unset state
return $r
}
# -------------------------------------------------------------------------
# HMAC Hashed Message Authentication (RFC 2104)
#
# hmac = H(K xor opad, H(K xor ipad, text))
#
# HMACInit --
#
# This is equivalent to the SHA1Init procedure except that a key is
# added into the algorithm
#
proc ::sha2::HMACInit {K} {
# Key K is adjusted to be 64 bytes long. If K is larger, then use
# the SHA1 digest of K and pad this instead.
set len [string length $K]
if {$len > 64} {
set tok [SHA256Init]
SHA256Update $tok $K
set K [SHA256Final $tok]
set len [string length $K]
}
set pad [expr {64 - $len}]
append K [string repeat \0 $pad]
# Cacluate the padding buffers.
set Ki {}
set Ko {}
binary scan $K i16 Ks
foreach k $Ks {
append Ki [binary format i [expr {$k ^ 0x36363636}]]
append Ko [binary format i [expr {$k ^ 0x5c5c5c5c}]]
}
set tok [SHA256Init]
SHA256Update $tok $Ki; # initialize with the inner pad
# preserve the Ko value for the final stage.
# FRINK: nocheck
set [subst $tok](Ko) $Ko
return $tok
}
# HMACUpdate --
#
# Identical to calling SHA256Update
#
proc ::sha2::HMACUpdate {token data} {
SHA256Update $token $data
return
}
# HMACFinal --
#
# This is equivalent to the SHA256Final procedure. The hash context is
# closed and the binary representation of the hash result is returned.
#
proc ::sha2::HMACFinal {token} {
upvar #0 $token state
set tok [SHA256Init]; # init the outer hashing function
SHA256Update $tok $state(Ko); # prepare with the outer pad.
SHA256Update $tok [SHA256Final $token]; # hash the inner result
return [SHA256Final $tok]
}
# -------------------------------------------------------------------------
# Description:
# This is the core SHA1 algorithm. It is a lot like the MD4 algorithm but
# includes an extra round and a set of constant modifiers throughout.
#
set ::sha2::SHA256Transform_body {
variable K
upvar #0 $token state
# FIPS 180-2: 6.2.2 SHA-256 Hash computation.
binary scan $msg I* blocks
set blockLen [llength $blocks]
for {set i 0} {$i < $blockLen} {incr i 16} {
set W [lrange $blocks $i [expr {$i+15}]]
# FIPS 180-2: 6.2.2 (1) Prepare the message schedule
# For t = 16 to 64
# let Wt = (sigma1(Wt-2) + Wt-7 + sigma0(Wt-15) + Wt-16)
set t2 13
set t7 8
set t15 0
set t16 -1
for {set t 16} {$t < 64} {incr t} {
lappend W [expr {([sigma1 [lindex $W [incr t2]]] \
+ [lindex $W [incr t7]] \
+ [sigma0 [lindex $W [incr t15]]] \
+ [lindex $W [incr t16]]) & 0xffffffff}]
}
# FIPS 180-2: 6.2.2 (2) Initialise the working variables
set A $state(A)
set B $state(B)
set C $state(C)
set D $state(D)
set E $state(E)
set F $state(F)
set G $state(G)
set H $state(H)
# FIPS 180-2: 6.2.2 (3) Do permutation rounds
# For t = 0 to 63 do
# T1 = h + SIGMA1(e) + Ch(e,f,g) + Kt + Wt
# T2 = SIGMA0(a) + Maj(a,b,c)
# h = g; g = f; f = e; e = d + T1; d = c; c = b; b = a;
# a = T1 + T2
#
for {set t 0} {$t < 64} {incr t} {
set T1 [expr {($H + [SIGMA1 $E] + [Ch $E $F $G]
+ [lindex $K $t] + [lindex $W $t]) & 0xffffffff}]
set T2 [expr {([SIGMA0 $A] + [Maj $A $B $C]) & 0xffffffff}]
set H $G
set G $F
set F $E
set E [expr {($D + $T1) & 0xffffffff}]
set D $C
set C $B
set B $A
set A [expr {($T1 + $T2) & 0xffffffff}]
}
# FIPS 180-2: 6.2.2 (4) Compute the intermediate hash
incr state(A) $A
incr state(B) $B
incr state(C) $C
incr state(D) $D
incr state(E) $E
incr state(F) $F
incr state(G) $G
incr state(H) $H
}
return
}
# -------------------------------------------------------------------------
# FIPS 180-2: 4.1.2 equation 4.2
proc ::sha2::Ch {x y z} {
return [expr {($x & $y) ^ (~$x & $z)}]
}
# FIPS 180-2: 4.1.2 equation 4.3
proc ::sha2::Maj {x y z} {
return [expr {($x & $y) ^ ($x & $z) ^ ($y & $z)}]
}
# FIPS 180-2: 4.1.2 equation 4.4
# (x >>> 2) ^ (x >>> 13) ^ (x >>> 22)
proc ::sha2::SIGMA0 {x} {
return [expr {[>>> $x 2] ^ [>>> $x 13] ^ [>>> $x 22]}]
}
# FIPS 180-2: 4.1.2 equation 4.5
# (x >>> 6) ^ (x >>> 11) ^ (x >>> 25)
proc ::sha2::SIGMA1 {x} {
return [expr {[>>> $x 6] ^ [>>> $x 11] ^ [>>> $x 25]}]
}
# FIPS 180-2: 4.1.2 equation 4.6
# s0 = (x >>> 7) ^ (x >>> 18) ^ (x >> 3)
proc ::sha2::sigma0 {x} {
#return [expr {[>>> $x 7] ^ [>>> $x 18] ^ (($x >> 3) & 0x1fffffff)}]
return [expr {((($x<<25) | (($x>>7) & (0x7FFFFFFF>>6))) \
^ (($x<<14) | (($x>>18) & (0x7FFFFFFF>>17))) & 0xFFFFFFFF) \
^ (($x>>3) & 0x1fffffff)}]
}
# FIPS 180-2: 4.1.2 equation 4.7
# s1 = (x >>> 17) ^ (x >>> 19) ^ (x >> 10)
proc ::sha2::sigma1 {x} {
#return [expr {[>>> $x 17] ^ [>>> $x 19] ^ (($x >> 10) & 0x003fffff)}]
return [expr {((($x<<15) | (($x>>17) & (0x7FFFFFFF>>16))) \
^ (($x<<13) | (($x>>19) & (0x7FFFFFFF>>18))) & 0xFFFFFFFF) \
^ (($x >> 10) & 0x003fffff)}]
}
# 32bit rotate-right
proc ::sha2::>>> {v n} {
return [expr {(($v << (32 - $n)) \
| (($v >> $n) & (0x7FFFFFFF >> ($n - 1)))) \
& 0xFFFFFFFF}]
}
# 32bit rotate-left
proc ::sha2::<<< {v n} {
return [expr {((($v << $n) \
| (($v >> (32 - $n)) \
& (0x7FFFFFFF >> (31 - $n))))) \
& 0xFFFFFFFF}]
}
# -------------------------------------------------------------------------
# We speed up the SHA256Transform code while maintaining readability in the
# source code by substituting inline for a number of functions.
# The idea is to reduce the number of [expr] calls.
# Inline the Ch function
regsub -all -line \
{\[Ch (\$[ABCDEFGH]) (\$[ABCDEFGH]) (\$[ABCDEFGH])\]} \
$::sha2::SHA256Transform_body \
{((\1 \& \2) ^ ((~\1) \& \3))} \
::sha2::SHA256Transform_body
# Inline the Maj function
regsub -all -line \
{\[Maj (\$[ABCDEFGH]) (\$[ABCDEFGH]) (\$[ABCDEFGH])\]} \
$::sha2::SHA256Transform_body \
{((\1 \& \2) ^ (\1 \& \3) ^ (\2 \& \3))} \
::sha2::SHA256Transform_body
# Inline the SIGMA0 function
regsub -all -line \
{\[SIGMA0 (\$[ABCDEFGH])\]} \
$::sha2::SHA256Transform_body \
{((((\1<<30) | ((\1>>2) \& (0x7FFFFFFF>>1))) \& 0xFFFFFFFF) \
^ (((\1<<19) | ((\1>>13) \& (0x7FFFFFFF>>12))) \& 0xFFFFFFFF) \
^ (((\1<<10) | ((\1>>22) \& (0x7FFFFFFF>>21))) \& 0xFFFFFFFF) \
)} \
::sha2::SHA256Transform_body
# Inline the SIGMA1 function
regsub -all -line \
{\[SIGMA1 (\$[ABCDEFGH])\]} \
$::sha2::SHA256Transform_body \
{((((\1<<26) | ((\1>>6) \& (0x7FFFFFFF>>5))) \& 0xFFFFFFFF) \
^ (((\1<<21) | ((\1>>11) \& (0x7FFFFFFF>>10))) \& 0xFFFFFFFF) \
^ (((\1<<7) | ((\1>>25) \& (0x7FFFFFFF>>24))) \& 0xFFFFFFFF) \
)} \
::sha2::SHA256Transform_body
proc ::sha2::SHA256Transform {token msg} $::sha2::SHA256Transform_body
# -------------------------------------------------------------------------
# Convert a integer value into a binary string in big-endian order.
proc ::sha2::byte {n v} {expr {((0xFF << (8 * $n)) & $v) >> (8 * $n)}}
proc ::sha2::bytes {v} {
#format %c%c%c%c [byte 3 $v] [byte 2 $v] [byte 1 $v] [byte 0 $v]
format %c%c%c%c \
[expr {((0xFF000000 & $v) >> 24) & 0xFF}] \
[expr {(0xFF0000 & $v) >> 16}] \
[expr {(0xFF00 & $v) >> 8}] \
[expr {0xFF & $v}]
}
# -------------------------------------------------------------------------
proc ::sha2::Hex {data} {
binary scan $data H* result
return $result
}
# -------------------------------------------------------------------------
# Description:
# Pop the nth element off a list. Used in options processing.
#
proc ::sha2::Pop {varname {nth 0}} {
upvar $varname args
set r [lindex $args $nth]
set args [lreplace $args $nth $nth]
return $r
}
# -------------------------------------------------------------------------
# fileevent handler for chunked file hashing.
#
proc ::sha2::Chunk {token channel {chunksize 4096}} {
upvar #0 $token state
if {[eof $channel]} {
fileevent $channel readable {}
set state(reading) 0
}
SHA256Update $token [read $channel $chunksize]
}
# -------------------------------------------------------------------------
proc ::sha2::_sha256 {ver args} {
array set opts {-hex 0 -filename {} -channel {} -chunksize 4096}
if {[llength $args] == 1} {
set opts(-hex) 1
} else {
while {[string match -* [set option [lindex $args 0]]]} {
switch -glob -- $option {
-hex { set opts(-hex) 1 }
-bin { set opts(-hex) 0 }
-file* { set opts(-filename) [Pop args 1] }
-channel { set opts(-channel) [Pop args 1] }
-chunksize { set opts(-chunksize) [Pop args 1] }
default {
if {[llength $args] == 1} { break }
if {[string compare $option "--"] == 0} { Pop args; break }
set err [join [lsort [concat -bin [array names opts]]] ", "]
return -code error "bad option $option:\
must be one of $err"
}
}
Pop args
}
}
if {$opts(-filename) != {}} {
set opts(-channel) [open $opts(-filename) r]
fconfigure $opts(-channel) -translation binary
}
if {$opts(-channel) == {}} {
if {[llength $args] != 1} {
return -code error "wrong # args: should be\
\"[namespace current]::sha$ver ?-hex|-bin? -filename file\
| -channel channel | string\""
}
set tok [SHA${ver}Init]
SHA${ver}Update $tok [lindex $args 0]
set r [SHA${ver}Final $tok]
} else {
set tok [SHA${ver}Init]
# FRINK: nocheck
set [subst $tok](reading) 1
fileevent $opts(-channel) readable \
[list [namespace origin Chunk] \
$tok $opts(-channel) $opts(-chunksize)]
# FRINK: nocheck
vwait [subst $tok](reading)
set r [SHA${ver}Final $tok]
# If we opened the channel - we should close it too.
if {$opts(-filename) != {}} {
close $opts(-channel)
}
}
if {$opts(-hex)} {
set r [Hex $r]
}
return $r
}
interp alias {} ::sha2::sha256 {} ::sha2::_sha256 256
interp alias {} ::sha2::sha224 {} ::sha2::_sha256 224
# -------------------------------------------------------------------------
proc ::sha2::hmac {args} {
array set opts {-hex 1 -filename {} -channel {} -chunksize 4096}
if {[llength $args] != 2} {
while {[string match -* [set option [lindex $args 0]]]} {
switch -glob -- $option {
-key { set opts(-key) [Pop args 1] }
-hex { set opts(-hex) 1 }
-bin { set opts(-hex) 0 }
-file* { set opts(-filename) [Pop args 1] }
-channel { set opts(-channel) [Pop args 1] }
-chunksize { set opts(-chunksize) [Pop args 1] }
default {
if {[llength $args] == 1} { break }
if {[string compare $option "--"] == 0} { Pop args; break }
set err [join [lsort [array names opts]] ", "]
return -code error "bad option $option:\
must be one of $err"
}
}
Pop args
}
}
if {[llength $args] == 2} {
set opts(-key) [Pop args]
}
if {![info exists opts(-key)]} {
return -code error "wrong # args:\
should be \"hmac ?-hex? -key key -filename file | string\""
}
if {$opts(-filename) != {}} {
set opts(-channel) [open $opts(-filename) r]
fconfigure $opts(-channel) -translation binary
}
if {$opts(-channel) == {}} {
if {[llength $args] != 1} {
return -code error "wrong # args:\
should be \"hmac ?-hex? -key key -filename file | string\""
}
set tok [HMACInit $opts(-key)]
HMACUpdate $tok [lindex $args 0]
set r [HMACFinal $tok]
} else {
set tok [HMACInit $opts(-key)]
# FRINK: nocheck
set [subst $tok](reading) 1
fileevent $opts(-channel) readable \
[list [namespace origin Chunk] \
$tok $opts(-channel) $opts(-chunksize)]
# FRINK: nocheck
vwait [subst $tok](reading)
set r [HMACFinal $tok]
# If we opened the channel - we should close it too.
if {$opts(-filename) != {}} {
close $opts(-channel)
}
}
if {$opts(-hex)} {
set r [Hex $r]
}
return $r
}
# -------------------------------------------------------------------------
# Try and load a compiled extension to help.
namespace eval ::sha2 {
variable e {}
foreach e [KnownImplementations] {
if {[LoadAccelerator $e]} {
SwitchTo $e
break
}
}
unset e
}
package provide sha256 1.0.3
# -------------------------------------------------------------------------
# Local Variables:
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