'dev sha-1 as function by homa 02/2024
'all variables are unsigned 32-bit
Option EXPLICIT
Print sha1("mmbasic_sha-1")
End
'
'SHA-1 hash function, takes an input (maximum 183 character!!)
'and produces a 160-bit(20-byte) hash value
Function sha1(m$) As string
 'Initializing hash variables
 Local h0=&h67452301
 Local h1=&hEFCDAB89
 Local h2=&h98BADCFE
 Local h3=&h10325476
 Local h4=&hC3D2E1F0
 '
 Local block$(2) As string 'or chunk
 Local word(79) As integer
 Local w As integer 'w ord counter
 Local pm$ As string
 Local ol, pl As integer  'original length, padded length
 Local b, bmax As integer 'b lock max and counter
 Local wa,wb,wc,wd,we,wf, wk, wtemp As integer
 '
 'Pre-processing (padding message)
 ol=Len(m$)
 pm$=m$+Chr$(&h80)
 pl=448-((ol+1)*8 Mod 512)
 pm$=pm$+String$(pl/8, 0)
 pm$=pm$+Bin2str$(int64,ol*8,big) 'big-endian format!
 '
 'Break padded message into blocks of 512 bits (maximum of 3)
 'This also means a maximum of 183 characters for the incoming message!
 'as the basic length of string in mmbasic is 255 characters!
 Select Case Len(pm$)
   Case 64
     block$(0)=pm$
     bmax=0
   Case 128
     block$(0)=Mid$(pm$,1,64)
     block$(1)=Mid$(pm$,65,64)
     bmax=1
   Case 192
     block$(0)=Mid$(pm$,1,64)
     block$(1)=Mid$(pm$,65,64)
     block$(2)=Mid$(pm$,129,64)
     bmax=2
   Case Else
     bmax=-1
 End Select
 '
 For b=0 To bmax 'main loop
   'words |  split block in 16 32-bit big-endian words w(i), 0 = i = 15
   For w=0 To 15
     word(w)=Str2bin(uint32,Mid$(block$(b),w*4+1,4),big)
   Next w
   For w=16 To 79 ' and extend
     word(w)=(word(w-3) Xor word(w-8) Xor word(w-14) Xor word(w-16))
     word(w) = lrt(word(w), 1)
   Next w
   'Initializing the working variables
   wa=h0
   wb=h1
   wc=h2
   wd=h3
   we=h4
   'Compression function
   For w=0 To 79
     Select Case w
       Case 0 To 19
         'wf=(wb And wc) Or ((Not wb) And wd)
         wf= wd Xor (wb And (wc Xor wd))      'Alternative required by NOT
         wk=&h5A827999
       Case 20 To 39
         wf=wb Xor wc Xor wd
         wk=&h6ED9EBA1
       Case 40 To 59
         wf=(wb And wc) Or (wb And wd) Or (wc And wd)
         wk=&h8F1BBCDC
       Case 60 To 79
         wf=wb Xor wc Xor wd
         wk=&hCA62C1D6
     End Select
     '... fix it with ... And &hFFFFFFFF ... due to 32bit!
     wtemp = (  lrt(wa, 5) + wf  ) And &hFFFFFFFF
     wtemp = (  wtemp + we       ) And &hFFFFFFFF
     wtemp = (  wtemp + wk       ) And &hFFFFFFFF
     wtemp = (  wtemp + word(w)  ) And &hFFFFFFFF
     we = wd
     wd = wc
     wc = lrt(wb, 30)
     wb = wa
     wa = wtemp
   Next w
   'Add this block's hash to result so far
   'and the 64to32bit-FIX
   h0 = ( h0 + wa ) And &hFFFFFFFF
   h1 = ( h1 + wb ) And &hFFFFFFFF
   h2 = ( h2 + wc ) And &hFFFFFFFF
   h3 = ( h3 + wd ) And &hFFFFFFFF
   h4 = ( h4 + we ) And &hFFFFFFFF
 Next b
 'digest hash - string hex
 sha1=Hex$(h0,8)+Hex$(h1,8)+Hex$(h2,8)+Hex$(h3,8)+Hex$(h4,8)
End Function
'
Function lrt(a1,a2) 'left rotate for 32bit
 lrt =( (a1 << a2) Or (a1 >> (32-a2)) ) And &hFFFFFFFF
End Function

> option list
PicoMiteVGA MMBasic Version 5.08.00
OPTION SYSTEM I2C GP14,GP15
OPTION COLOURCODE ON
OPTION KEYBOARD GR
OPTION CPUSPEED (KHz) 252000
OPTION SDCARD GP13, GP10, GP11, GP12
OPTION AUDIO GP4,GP5', ON PWM CHANNEL 2
OPTION RTC AUTO ENABLE
OPTION MODBUFF ENABLE
> run
004C50C315E7D77687F670F68EE12D6E7579A3FC
>