des.tcl

Linux下的MSN聊天程序源码

		    # puts "right2: [format %x $right2]";

		    # The result is attained by passing these bytes through the S selection functions
		    set temp $left;
		    set left $right;
		    set right [expr {$temp ^ ([lindex $spfunction2 [expr {($right1 >> 24) & 0x3f}]] | \
						 [lindex $spfunction4 [expr {($right1 >> 16) & 0x3f}]] | \
						 [lindex $spfunction6 [expr {($right1 >>  8) & 0x3f}]] | \
						 [lindex $spfunction8 [expr {$right1 & 0x3f}]] | \
						 [lindex $spfunction1 [expr {($right2 >> 24) & 0x3f}]] | \
						 [lindex $spfunction3 [expr {($right2 >> 16) & 0x3f}]] | \
						 [lindex $spfunction5 [expr {($right2 >>  8) & 0x3f}]] | \
						  [lindex $spfunction7 [expr {$right2 & 0x3f}]])}];
 
		    # puts "Left iter: [format %x $left]";
		    # puts "Right iter: [format %x $right]";

		}
		set temp $left;
		set left $right;
		set right $temp; # Unreverse left and right
	    }; # For either 1 or 3 iterations

	    #puts "Left Iterated: [format %x $left]";
	    #puts "Right Iterated: [format %x $right]";

	    # Move then each one bit to the right
	    set left [expr {((($left >> 1) & 0x7fffffff) | (($left << 31) & 0xffffffff))}]; 
	    set right [expr {((($right >> 1) & 0x7fffffff) | (($right << 31) & 0xffffffff))}]; 

	    #puts "Left shifted: [format %x $left]";
	    #puts "Right shifted: [format %x $right]";

	    # Now perform IP-1, which is IP in the opposite direction
	    set temp [expr {((($left >> 1) & 0x7fffffff) ^ $right) & 0x55555555}];
	    set right [expr {$right ^ $temp}];
	    set left [expr {$left ^ ($temp << 1)}];
	    set temp [expr {((($right >> 8) & 0x00ffffff) ^ $left) & 0x00ff00ff}];
	    set left [expr {$left ^ $temp}];
	    set right [expr {$right ^ ($temp << 8)}];
	    set temp [expr {((($right >> 2) & 0x3fffffff) ^ $left) & 0x33333333}]; 
	    set left [expr {$left ^ $temp}];
	    set right [expr {$right ^ ($temp << 2)}];
	    set temp [expr {((($left >> 16) & 0x0000ffff) ^ $right) & 0x0000ffff}];
	    set right [expr {$right ^ $temp}];
	    set left [expr {$left ^ ($temp << 16)}];
	    set temp [expr {((($left >> 4) & 0x0fffffff) ^ $right) & 0x0f0f0f0f}];
	    set right [expr {$right ^ $temp}];
	    set left [expr {$left ^ ($temp << 4)}];

	    #puts "Left IP-1: [format %x $left]";
	    #puts "Right IP-1: [format %x $right]";

	    # For Cipher Block Chaining mode, xor the message with the previous result
	    if {$mode == 1} {
		if {$encrypt} {
		    set cbcleft $left;
		    set cbcright $right;
		} else {
		    set left [expr {$left ^ $cbcleft2}];
		    set right [expr {$right ^ $cbcright2}];
		}
	    }

	    append tempresult [binary format H16 [format %08x%08x $left $right]]

	    #puts "Left final: [format %x $left]";
	    #puts "Right final: [format %x $right]";

	    incr chunk 8;
	    if {$chunk == 512} {
		append result $tempresult
		set tempresult {};
		set chunk 0;
	    }
	}; # For every 8 characters, or 64 bits in the message

	# Return the result as an array
	return ${result}$tempresult
    }; # End of des

    if { $initialize_amsn == 1 } {
 
	variable pc2bytes0 [list 0 0x4 0x20000000 0x20000004 0x10000 0x10004 0x20010000 0x20010004 0x200 0x204 0x20000200 0x20000204 0x10200 0x10204 0x20010200 0x20010204]
	variable pc2bytes1 [list 0 0x1 0x100000 0x100001 0x4000000 0x4000001 0x4100000 0x4100001 0x100 0x101 0x100100 0x100101 0x4000100 0x4000101 0x4100100 0x4100101]
	variable pc2bytes2 [list 0 0x8 0x800 0x808 0x1000000 0x1000008 0x1000800 0x1000808 0 0x8 0x800 0x808 0x1000000 0x1000008 0x1000800 0x1000808]
	variable pc2bytes3 [list 0 0x200000 0x8000000 0x8200000 0x2000 0x202000 0x8002000 0x8202000 0x20000 0x220000 0x8020000 0x8220000 0x22000 0x222000 0x8022000 0x8222000]
	variable pc2bytes4 [list 0 0x40000 0x10 0x40010 0 0x40000 0x10 0x40010 0x1000 0x41000 0x1010 0x41010 0x1000 0x41000 0x1010 0x41010]
	variable pc2bytes5 [list 0 0x400 0x20 0x420 0 0x400 0x20 0x420 0x2000000 0x2000400 0x2000020 0x2000420 0x2000000 0x2000400 0x2000020 0x2000420]
	variable pc2bytes6 [list 0 0x10000000 0x80000 0x10080000 0x2 0x10000002 0x80002 0x10080002 0 0x10000000 0x80000 0x10080000 0x2 0x10000002 0x80002 0x10080002]
	variable pc2bytes7 [list 0 0x10000 0x800 0x10800 0x20000000 0x20010000 0x20000800 0x20010800 0x20000 0x30000 0x20800 0x30800 0x20020000 0x20030000 0x20020800 0x20030800]
	variable pc2bytes8 [list 0 0x40000 0 0x40000 0x2 0x40002 0x2 0x40002 0x2000000 0x2040000 0x2000000 0x2040000 0x2000002 0x2040002 0x2000002 0x2040002]
	variable pc2bytes9 [list 0 0x10000000 0x8 0x10000008 0 0x10000000 0x8 0x10000008 0x400 0x10000400 0x408 0x10000408 0x400 0x10000400 0x408 0x10000408]
	variable pc2bytes10 [list 0 0x20 0 0x20 0x100000 0x100020 0x100000 0x100020 0x2000 0x2020 0x2000 0x2020 0x102000 0x102020 0x102000 0x102020]
	variable pc2bytes11 [list 0 0x1000000 0x200 0x1000200 0x200000 0x1200000 0x200200 0x1200200 0x4000000 0x5000000 0x4000200 0x5000200 0x4200000 0x5200000 0x4200200 0x5200200]
	variable pc2bytes12 [list 0 0x1000 0x8000000 0x8001000 0x80000 0x81000 0x8080000 0x8081000 0x10 0x1010 0x8000010 0x8001010 0x80010 0x81010 0x8080010 0x8081010]
	variable pc2bytes13 [list 0 0x4 0x100 0x104 0 0x4 0x100 0x104 0x1 0x5 0x101 0x105 0x1 0x5 0x101 0x105]

	# Now define the left shifts which need to be done
	variable shifts {0  0  1  1  1  1  1  1  0  1  1  1  1  1  1  0};
    }

    # Procedure: createKeys
    # Input:
    #   key     : The 64-bit DES key or the 192-bit 3DES key
    #             (Note: The lsb of each byte is ignored; odd parity
    #             is not required).
    # Output:
    # The 16 (DES) or 48 (3DES) subkeys.
    proc createKeys {key} {
	variable pc2bytes0
	variable pc2bytes1
	variable pc2bytes2
	variable pc2bytes3
	variable pc2bytes4
	variable pc2bytes5
	variable pc2bytes6
	variable pc2bytes7
	variable pc2bytes8
	variable pc2bytes9
	variable pc2bytes10
	variable pc2bytes11
	variable pc2bytes12
	variable pc2bytes13
	variable shifts

	# How many iterations (1 for des, 3 for triple des)
	set iterations [expr {([string length $key] >= 24) ? 3 : 1}];
	# Stores the return keys
	set keys {}
	# Other variables
	set lefttemp {}; set righttemp {}
	set m 0
	# Either 1 or 3 iterations
	for {set j 0} {$j < $iterations} {incr j} {
	    binary scan $key x${m}H8H8 lefttemp righttemp
	    set left {}
	    append left "0x" $lefttemp
	    set right {}
	    append right "0x" $righttemp
	    incr m 8

	    #puts "Left key: $left"
	    #puts "Right key: $right"

	    set temp [expr {(($left >> 4) ^ $right) & 0x0f0f0f0f}]
	    set right [expr {$right ^ $temp}]
	    set left [expr {$left ^ ($temp << 4)}]
	    set temp [expr {(($right >> 16) ^ $left) & 0x0000ffff}]
	    set left [expr {$left ^ $temp}]
	    set right [expr {$right ^ ($temp << 16)}]
	    set temp [expr {(($left >> 2) ^ $right) & 0x33333333}]
	    set right [expr {$right ^ $temp}]
	    set left [expr {$left ^ ($temp << 2)}]
	    set temp [expr {(($right >> 16) ^ $left) & 0x0000ffff}]
	    set left [expr {$left ^ $temp}]
	    set right [expr {$right ^ ($temp << 16)}]
	    set temp [expr {(($left >> 1) ^ $right) & 0x55555555}]
	    set right [expr {$right ^ $temp}]
	    set left [expr {$left ^ ($temp << 1)}]
	    set temp [expr {(($right >> 8) ^ $left) & 0x00ff00ff}]
	    set left [expr {$left ^ $temp}]
	    set right [expr {$right ^ ($temp << 8)}]
	    set temp [expr {(($left >> 1) ^ $right) & 0x55555555}]
	    set right [expr {$right ^ $temp}]
	    set left [expr {$left ^ ($temp << 1)}]
	    
	    #puts "Left key PC1: [format %x $left]"
	    #puts "Right key PC1: [format %x $right]"

	    # The right side needs to be shifted and to get the last four bits of the left side
	    set temp [expr {($left << 8) | (($right >> 20) & 0x000000f0)}];
	    # Left needs to be put upside down
	    set left [expr {($right << 24) | (($right << 8) & 0x00ff0000) | \
				(($right >> 8) & 0x0000ff00) | (($right >> 24) & 0x000000f0)}];
	    set right $temp;

	    #puts "Left key juggle: [format %x $left]"
	    #puts "Right key juggle: [format %x $right]"

	    # Now go through and perform these shifts on the left and right keys
	    foreach i $shifts  {
		# Shift the keys either one or two bits to the left
		if {$i} {
		    set left [expr {($left << 2) | (($left >> 26) & 0x0000003f)}];
		    set right [expr {($right << 2) | (($right >> 26) & 0x0000003f)}];
		} else {
		    set left [expr {($left << 1) | (($left >> 27) & 0x0000001f)}];
		    set right [expr {($right << 1) | (($right >> 27) & 0x0000001f)}];
		}
		set left [expr {$left & 0xfffffff0}];
		set right [expr {$right & 0xfffffff0}];

		# Now apply PC-2, in such a way that E is easier when encrypting or decrypting
		# this conversion will look like PC-2 except only the last 6 bits of each byte are used
		# rather than 48 consecutive bits and the order of lines will be according to 
		# how the S selection functions will be applied: S2, S4, S6, S8, S1, S3, S5, S7
		set lefttemp [expr {[lindex $pc2bytes0 [expr {($left >> 28) & 0x0000000f}]] | \
					[lindex $pc2bytes1 [expr {($left >> 24) & 0x0000000f}]] | \
					[lindex $pc2bytes2 [expr {($left >> 20) & 0x0000000f}]] | \
					[lindex $pc2bytes3 [expr {($left >> 16) & 0x0000000f}]] | \
					[lindex $pc2bytes4 [expr {($left >> 12) & 0x0000000f}]] | \
					[lindex $pc2bytes5 [expr {($left >> 8) & 0x0000000f}]] | \
					[lindex $pc2bytes6 [expr {($left >> 4) & 0x0000000f}]]}];
		set righttemp [expr {[lindex $pc2bytes7 [expr {($right >> 28) & 0x0000000f}]] | \
					 [lindex $pc2bytes8 [expr {($right >> 24) & 0x0000000f}]] | \
					 [lindex $pc2bytes9 [expr {($right >> 20) & 0x0000000f}]] | \
					 [lindex $pc2bytes10 [expr {($right >> 16) & 0x0000000f}]] | \
					 [lindex $pc2bytes11 [expr {($right >> 12) & 0x0000000f}]] | \
					 [lindex $pc2bytes12 [expr {($right >> 8) & 0x0000000f}]] | \
					 [lindex $pc2bytes13 [expr {($right >> 4) & 0x0000000f}]]}];
		set temp [expr {(($righttemp >> 16) ^ $lefttemp) & 0x0000ffff}];
		lappend keys [expr {$lefttemp ^ $temp}];
		lappend keys [expr {$righttemp ^ ($temp << 16)}];
	    }
	}; # For each iterations
	# Return the keys we've created
	return $keys;
    }; # End of createKeys
}; # End of des namespace eval

package provide tclDES 0.5