trygen.py

#!/usr/bin/env python

import sys

operation = sys.argv[1]

var = []
function = []
loop = []
expected = '0'
unexpected = 'nonzero'
extrabytes = '0'

if operation == 'core':
  loop = 512
  var = [['h','OUTPUTBYTES'],['n','INPUTBYTES'],['k','KEYBYTES'],['c','CONSTBYTES']]
  function = [['',['h'],[],['n','k','c']]]

if operation == 'hashblocks':
  loop = 4096
  var = [['h','STATEBYTES'],['m',0]]
  function = [['',[],['h'],['m','mlen']]]
  expected = 'mlen % crypto_hashblocks_BLOCKBYTES'
  unexpected = 'unexpected value'

if operation == 'hash':
  loop = 64
  var = [['h','BYTES'],['m',0]]
  function = [['',['h'],[],['m','mlen']]]

if operation == 'stream':
  loop = 512
  var = [['k','KEYBYTES'],['n','NONCEBYTES'],['m',0],['c',0],['s',0]]
  function = [['',['s'],[],['slen','n','k']],['_xor',['c'],[],['m','mlen','n','k']]]

if operation in ['auth','onetimeauth']:
  loop = 4096
  var = [['h','BYTES'],['m',0],['k','KEYBYTES']]
  function = [['',['h'],[],['m','mlen','k']],['_verify',[],[],['h','m','mlen','k']]]

if operation == 'secretbox':
  loop = 4096
  var = [['k','KEYBYTES']]
  var += [['n','NONCEBYTES']]
  var += [['m',0]] # original message
  var += [['c',0]] # boxed message
  var += [['t',0]] # opened message
  function = [['',['c'],[],['m','mlen','n','k']]]
  function += [['_open',['t'],[],['c','clen','n','k']]]

if operation == 'aead':
  loop = 64
  var = [['k','KEYBYTES']]
  var += [['s','NSECBYTES']]
  var += [['p','NPUBBYTES']]
  var += [['a',0]] # additional data
  var += [['m',0]] # original message
  var += [['c',0]] # boxed message
  var += [['t',0]] # opened message
  var += [['r','NSECBYTES']] # opened s
  function = [['_encrypt',['c','&clen'],[],['m','mlen','a','alen','s','p','k']]]
  function += [['_decrypt',['t','&tlen','r'],[],['c','clen','a','alen','p','k']]]
  extrabytes = 'crypto_aead_ABYTES'

if operation == 'scalarmult':
  loop = 64
  var = [['a','SCALARBYTES']] # alice secret key
  var += [['b','SCALARBYTES']] # bob secret key
  var += [['c','BYTES']] # alice public key
  var += [['d','BYTES']] # bob public key
  var += [['e','BYTES']] # alice shared secret
  var += [['f','BYTES']] # bob shared secret
  function = [['_base',['c'],[],['a']]]
  function += [['_base',['d'],[],['b']]]
  function += [['',['e'],[],['a','d']]]
  function += [['',['f'],[],['b','c']]]

if operation == 'box':
  loop = 512
  var = [['a','SECRETKEYBYTES']] # alice secret key
  var += [['b','SECRETKEYBYTES']] # bob secret key
  var += [['y','PUBLICKEYBYTES']] # alice public key
  var += [['z','PUBLICKEYBYTES']] # bob public key
  var += [['e','BEFORENMBYTES']] # alice shared secret
  var += [['f','BEFORENMBYTES']] # bob shared secret
  var += [['n','NONCEBYTES']]
  var += [['m',0]] # original message
  var += [['c',0]] # boxed message
  var += [['d',0]] # boxed message, second try
  var += [['t',0]] # opened message
  function = [['_keypair',['y','a'],[],[]]]
  function += [['_keypair',['z','b'],[],[]]]
  function += [['',['c'],[],['m','mlen','n','z','a']]]
  function += [['_open',['t'],[],['c','clen','n','y','b']]]
  function += [['_beforenm',['e'],[],['z','a']]]
  function += [['_beforenm',['f'],[],['y','b']]]
  function += [['_afternm',['d'],[],['m','mlen','n','e']]]
  function += [['_open_afternm',['t'],[],['d','dlen','n','f']]]

if operation == 'dh':
  loop = 64
  var = [['a','SECRETKEYBYTES']] # alice secret key
  var += [['b','SECRETKEYBYTES']] # bob secret key
  var += [['c','PUBLICKEYBYTES']] # alice public key
  var += [['d','PUBLICKEYBYTES']] # bob public key
  var += [['e','BYTES']] # alice shared secret
  var += [['f','BYTES']] # bob shared secret
  function = [['_keypair',['c','a'],[],[]]]
  function += [['_keypair',['d','b'],[],[]]]
  function += [['',['e'],[],['d','a']]]
  function += [['',['f'],[],['c','b']]]

if operation == 'sign':
  loop = 8
  var = [['p','PUBLICKEYBYTES']]
  var += [['s','SECRETKEYBYTES']]
  var += [['m',0]] # original message
  var += [['c',0]] # signed message
  var += [['t',0]] # opened message
  function = [['_keypair',['p','s'],[],[]]]
  function += [['',['c','&clen'],[],['m','mlen','s']]]
  function += [['_open',['t','&tlen'],[],['c','clen','p']]]
  extrabytes = 'crypto_sign_BYTES'

if operation == 'encrypt':
  loop = 8
  var = [['p','PUBLICKEYBYTES']]
  var += [['s','SECRETKEYBYTES']]
  var += [['m',0]] # original message
  var += [['c',0]] # encrypted message
  var += [['t',0]] # opened message
  function = [['_keypair',['p','s'],[],[]]]
  function += [['',['c','&clen'],[],['m','mlen','p']]]
  function += [['_open',['t','&tlen'],[],['c','clen','s']]]
  extrabytes = 'crypto_encrypt_BYTES'

length = dict()
for v,n in var: length[v] = n

print '/*'
print ' * crypto_%s/try.c version 20140429' % operation
print ' * D. J. Bernstein'
print ' * Public domain.'
print ' * Auto-generated by trygen.py; do not edit.'
print ' */'
print ''
print '#include "crypto_%s.h"' % operation
print '#include "try.h"'
if operation in ['encrypt','sign']:
  print '#include "randombytes.h"'
print ''
print 'const char *primitiveimplementation = crypto_%s_IMPLEMENTATION;' % operation
print ''

tunebytes = not operation in ['core','dh','scalarmult']
if tunebytes:
  print '#define TUNE_BYTES 1536'
  print '#ifdef SMALL'
  print '#define MAXTEST_BYTES 128'
  print '#else'
  print '#define MAXTEST_BYTES 4096'
  print '#endif'

print '#ifdef SMALL'
print '#define LOOPS %s' % loop
print '#else'
print '#define LOOPS %s' % (loop * 8)
print '#endif'
print ''

for v,n in var:
  print 'static unsigned char *%s;' % v

for v,n in var:
  print 'static unsigned char *%s2;' % v

for v,n in var:
  if n == 0:
    print 'unsigned long long %slen;' % v
  else:
    print '#define %slen crypto_%s_%s' % (v,operation,n)

# preallocate(): before resource limits are set
print ''
print 'void preallocate(void)'
print '{'
if operation in ['dh','encrypt','sign']:
  print '#ifdef RAND_R_PRNG_NOT_SEEDED'
  print '  RAND_status();'
  print '#endif'
print '}'

# allocate(): set aside storage for test, predoit, doit
print ''
print 'void allocate(void)'
print '{'
print '  unsigned long long alloclen = 0;'
if tunebytes:
  print '  if (alloclen < TUNE_BYTES) alloclen = TUNE_BYTES;'
  if extrabytes != '0':
    print '  if (alloclen < MAXTEST_BYTES + %s) alloclen = MAXTEST_BYTES + %s;' % (extrabytes,extrabytes)
  else:
    print '  if (alloclen < MAXTEST_BYTES) alloclen = MAXTEST_BYTES;'
for v,n in var:
  if n:
    print '  if (alloclen < crypto_%s_%s) alloclen = crypto_%s_%s;' % (operation,n,operation,n)
for v,n in var:
  print '  %s = alignedcalloc(alloclen);' % v
for v,n in var:
  print '  %s2 = alignedcalloc(alloclen);' % v
print '}'

# predoit(): precomputations for doit
print ''
print 'void predoit(void)'
print '{'
if operation == 'scalarmult':
  print '  randombytes(a,alen);'
  print '  randombytes(b,blen);'
if operation == 'box':
  print '  crypto_box_keypair(y,a);'
  print '  crypto_box_keypair(z,b);'
  print '  randombytes(m,mlen);'
  print '  randombytes(n,nlen);'
if operation == 'encrypt':
  print '  crypto_encrypt_keypair(p,s);'
  print '  mlen = TUNE_BYTES;'
  print '  clen = 0;'
  print '  randombytes(m,mlen);'
if operation == 'sign':
  print '  crypto_sign_keypair(p,s);'
  print '  mlen = TUNE_BYTES;'
  print '  clen = 0;'
  print '  randombytes(m,mlen);'
print '}'

# doit(): main computations to select implementation
print ''
print 'void doit(void)'
print '{'
if operation == 'aead':
  print '  crypto_aead_encrypt(c,&clen,m,TUNE_BYTES,a,TUNE_BYTES,s,p,k);'
  print '  crypto_aead_decrypt(t,&tlen,r,c,clen,a,TUNE_BYTES,p,k);'
if operation == 'auth':
  print '  crypto_auth(h,m,TUNE_BYTES,k);'
  print '  crypto_auth_verify(h,m,TUNE_BYTES,k);'
if operation == 'box':
  print '  crypto_box(c,m,TUNE_BYTES + crypto_box_ZEROBYTES,n,y,b);'
  print '  crypto_box_open(t,c,TUNE_BYTES + crypto_box_ZEROBYTES,n,z,a);'
if operation == 'core':
  print '  crypto_core(h,n,k,c);'
if operation == 'dh':
  print '  crypto_dh_keypair(c,a);'
  print '  crypto_dh_keypair(d,b);'
  print '  crypto_dh(e,d,a);'
  print '  crypto_dh(f,c,b);'
if operation == 'encrypt':
  print '  crypto_encrypt(c,&clen,m,mlen,p);'
  print '  crypto_encrypt_open(t,&tlen,c,clen,s);'
if operation == 'hashblocks':
  print '  crypto_hashblocks(h,m,TUNE_BYTES);'
if operation == 'hash':
  print '  crypto_hash(h,m,TUNE_BYTES);'
if operation == 'onetimeauth':
  print '  crypto_onetimeauth(h,m,TUNE_BYTES,k);'
  print '  crypto_onetimeauth_verify(h,m,TUNE_BYTES,k);'
if operation == 'scalarmult':
  print '  crypto_scalarmult_base(c,a);'
  print '  crypto_scalarmult_base(d,b);'
  print '  crypto_scalarmult(e,a,d);'
  print '  crypto_scalarmult(f,b,c);'
if operation == 'secretbox':
  print '  crypto_secretbox(c,m,TUNE_BYTES + crypto_secretbox_ZEROBYTES,n,k);'
  print '  crypto_secretbox_open(t,c,TUNE_BYTES + crypto_secretbox_ZEROBYTES,n,k);'
if operation == 'sign':
  print '  crypto_sign(c,&clen,m,mlen,s);'
  print '  crypto_sign_open(t,&tlen,c,clen,p);'
if operation == 'stream':
  print '  crypto_stream_xor(c,m,TUNE_BYTES,n,k);'
if operation == 'verify':
  print '  crypto_verify(x,y);'
print '}'

# test(): try test vectors, compute checksum
print ''
print 'void test(void)'
print '{'
indent = '  '
if operation in ['stream','secretbox','box']:
  print indent+'unsigned long long j;'
print indent+'unsigned long long loop;'
print indent
print indent+'for (loop = 0;loop < LOOPS;++loop) {'
indent += '  '

if not operation in ['core','scalarmult','dh']:
  print indent+'mlen = myrandom() % (MAXTEST_BYTES + 1);'

if operation == 'aead':
  print indent+'alen = myrandom() % (MAXTEST_BYTES + 1);'
if operation == 'stream':
  print indent+'clen = mlen;'
  print indent+'slen = mlen;'
if operation == 'secretbox':
  print indent+'clen = mlen;'
  print indent+'tlen = mlen;'
  print indent+'if (mlen < crypto_%s_ZEROBYTES) continue;' % operation
if operation == 'box':
  print indent+'clen = mlen;'
  print indent+'dlen = mlen;'
  print indent+'tlen = mlen;'
  print indent+'if (mlen < crypto_%s_ZEROBYTES) continue;' % operation

initialized = set()

for f,output,inout,input in function:
  print indent
  cof = 'crypto_'+operation+f

  if cof in ['crypto_aead_encrypt']:
    print indent+'clen = mlen + crypto_%s_ABYTES;' % operation
  if cof in ['crypto_encrypt','crypto_sign']:
    print indent+'clen = mlen + %s_BYTES;' % cof
  if cof in ['crypto_encrypt_open','crypto_sign_open','crypto_aead_decrypt']:
    print indent+'tlen = clen;'

  for v in output:
    if len(v) == 1:
      print indent+'output_prepare(%s2,%s,%slen);' % (v,v,v)
      # v now has CDE where C is canary, D is canary, E is canary
      # v2 now has same CDE
      # D is at start of v with specified length
      # C is 16 bytes before beginning
      # E is 16 bytes past end
  for v in input + inout:
    if len(v) == 1:
      if v in initialized:
        print indent+'memcpy(%s2,%s,%slen);' % (v,v,v)
        print indent+'double_canary(%s2,%s,%slen);' % (v,v,v)
      else:
        print indent+'input_prepare(%s2,%s,%slen);' % (v,v,v)
        # v now has CTE where C is canary, T is test data, E is canary
        # v2 has same CTE
        initialized.add(v)

  if cof in ['crypto_secretbox','crypto_box']:
    print indent+'for (j = 0;j < %s_ZEROBYTES;++j) m[j] = 0;' % cof
    print indent+'for (j = 0;j < %s_ZEROBYTES;++j) m2[j] = 0;' % cof

  args = ','.join(output + inout + input)
  print indent+'if (%s(%s) != %s) fail("%s returns %s");' % (cof,args,expected,cof,unexpected)

  if cof in ['crypto_encrypt','crypto_sign','crypto_aead_encrypt']:
    print indent+'if (clen < mlen) fail("%s returns smaller output than input");' % cof
    print indent+'if (clen > mlen + %s) fail("%s returns more than %s extra bytes");' % (extrabytes,cof,extrabytes)
  if cof in ['crypto_encrypt_open','crypto_sign_open','crypto_aead_decrypt']:
    print indent+'if (tlen != mlen) fail("%s does not match mlen");' % cof
  if cof in ['crypto_encrypt_open','crypto_sign_open','crypto_aead_decrypt','crypto_secretbox_open','crypto_box_open','crypto_box_open_afternm']:
    print indent+'if (memcmp(t,m,mlen) != 0) fail("%s does not match m");' % cof
  if cof in ['crypto_aead_decrypt']:
    print indent+'if (memcmp(r,s,slen) != 0) fail("%s does not match s");' % cof
  if cof in ['crypto_box_afternm']:
    print indent+'if (memcmp(d,c,clen) != 0) fail("%s does not match c");' % cof
  if cof in ['crypto_secretbox','crypto_box']:
    print indent+'for (j = 0;j < %s_BOXZEROBYTES;++j)' % cof
    print indent+'  if (c[j] != 0) fail("%s does not clear extra bytes");' % cof

  if cof == 'crypto_stream_xor':
    print indent
    print indent+'for (j = 0;j < mlen;++j)'
    print indent+'  if ((s[j] ^ m[j]) != c[j]) fail("crypto_stream_xor does not match crypto_stream");'

  for v in output + inout:
    if len(v) == 1:
      print indent+'checksum(%s,%slen);' % (v,v)
      # output v,v2 now has COE,CDE where O is output; checksum O
      initialized.add(v)
  for v in output + inout:
    if len(v) == 1:
      if cof == 'crypto_sign_open' and v == 't':
        print indent+'output_compare(%s2,%s,%slen,"%s");' % (v,v,'c',cof)
      elif cof == 'crypto_aead_decrypt' and v == 't':
        print indent+'output_compare(%s2,%s,%slen,"%s");' % (v,v,'c',cof)
      else:
        print indent+'output_compare(%s2,%s,%slen,"%s");' % (v,v,v,cof)
        # output_compare checks COE,CDE for equal C, equal E
  for v in input:
    if len(v) == 1:
      print indent+'input_compare(%s2,%s,%slen,"%s");' % (v,v,v,cof)
      # input_compare checks CTE,CTE for equal C, equal T, equal E

  deterministic = True
  if inout + input == []: deterministic = False
  if cof == 'crypto_encrypt': deterministic = False

  if deterministic:
    print indent
    if cof == 'crypto_sign': print '#if crypto_sign_DETERMINISTIC == 1'
    for v in output + inout + input:
      if len(v) == 1:
        print indent+'double_canary(%s2,%s,%slen);' % (v,v,v)
        # old output v,v2: COE,CDE; new v,v2: FOG,FDG where F,G are new canaries
        # old inout v,v2: COE,CTE; new v,v2: FOG,FTG
        # old input v,v2: CTE,CTE; new v,v2: FTG,FTG
    args = ','.join([v if v[-3:] == 'len' else v+'2' for v in output + inout + input])
    print indent+'if (%s(%s) != %s) fail("%s returns %s");' % (cof,args,expected,cof,unexpected)
    for w in output + inout:
      if len(w) == 1:
        # w,w2: COE,COE; goal now is to compare O
        print indent+'if (memcmp(%s2,%s,%slen) != 0) fail("%s is nondeterministic");' % (w,w,w,cof)
    if cof == 'crypto_sign': print '#endif'

  overlap = deterministic
  if inout != []: overlap = False
  if cof == 'crypto_stream': overlap = False

  if overlap:
    for y in output:
      if len(y) == 1:
        print indent
        if cof == 'crypto_sign': print '#if crypto_sign_DETERMINISTIC == 1'
        if operation == 'aead': print '#if crypto_aead_NOOVERLAP == 1'
        if operation == 'aead': print '#else'
        for v in output:
          if len(v) == 1:
            print indent+'double_canary(%s2,%s,%slen);' % (v,v,v)
        for v in input:
          if len(v) == 1:
            print indent+'double_canary(%s2,%s,%slen);' % (v,v,v)
        # redundant: have already created output for this input
        # args = ','.join(output + input)
        # print indent+'if (%s(%s) != %s) fail("%s returns %s");' % (cof,args,expected,cof,unexpected)
        for x in input:
          if len(x) == 1:
            # try writing to x2 instead of y, while reading x2
            args = ','.join([x+'2' if v==y else v for v in output] + [x+'2' if v==x else v for v in input])
            print indent+'if (%s(%s) != %s) fail("%s with %s=%s overlap returns %s");' % (cof,args,expected,cof,x,y,unexpected)
            print indent+'if (memcmp(%s2,%s,%slen) != 0) fail("%s does not handle %s=%s overlap");' % (x,y,y,cof,x,y)
            print indent+'memcpy(%s2,%s,%slen);' % (x,x,x)
        if cof == 'crypto_sign': print '#endif'
        if operation == 'aead': print '#endif'

  if cof in ['crypto_auth_verify','crypto_onetimeauth_verify']:
    print indent
    for tweaks in range(3):
      print indent+'h[myrandom() % hlen] += 1 + (myrandom() % 255);'
      print indent+'if (%s(h,m,mlen,k) == 0)' % cof
      print indent+'  if (memcmp(h2,h,hlen) != 0)'
      print indent+'    fail("%s accepts modified authenticators");' % cof

  if cof in ['crypto_sign_open']:
    print indent
    for tweaks in range(3):
      print indent+'c[myrandom() % clen] += 1 + (myrandom() % 255);'
      print indent+'if (%s(t,&tlen,c,clen,p) == 0)' % cof
      print indent+'  if ((tlen != mlen) || (memcmp(t,m,mlen) != 0))'
      print indent+'    fail("%s allows trivial forgeries");' % cof

  if cof in ['crypto_aead_decrypt']:
    print indent
    for tweaks in range(3):
      print indent+'c[myrandom() % clen] += 1 + (myrandom() % 255);'
      print indent+'if (%s(t,&tlen,r,c,clen,a,alen,p,k) == 0)' % cof
      print indent+'  if ((tlen != mlen) || (memcmp(t,m,mlen) != 0) || (memcmp(r,s,slen) != 0))'
      print indent+'    fail("%s allows trivial forgeries");' % cof

  if cof in ['crypto_dh','crypto_scalarmult'] and output == ['f']:
    print indent
    print indent+'if (memcmp(f,e,elen) != 0) fail("%s not associative");' % cof

indent = indent[:-2]
print indent+'}'
print '}'