diff libtomcrypt/src/prngs/sober128.c @ 1478:3a933956437e coverity

update coverity
author Matt Johnston <matt@ucc.asn.au>
date Fri, 09 Feb 2018 23:49:22 +0800
parents 6dba84798cd5
children e9dba7abd939
line wrap: on
line diff
--- a/libtomcrypt/src/prngs/sober128.c	Sat Jun 24 23:33:16 2017 +0800
+++ b/libtomcrypt/src/prngs/sober128.c	Fri Feb 09 23:49:22 2018 +0800
@@ -5,196 +5,45 @@
  *
  * The library is free for all purposes without any express
  * guarantee it works.
- *
- * Tom St Denis, [email protected], http://libtom.org
  */
+
 #include "tomcrypt.h"
 
 /**
- @file sober128.c
+ @file prngs/sober128.c
  Implementation of SOBER-128 by Tom St Denis.
  Based on s128fast.c reference code supplied by Greg Rose of QUALCOMM.
 */
 
 #ifdef LTC_SOBER128
 
-#include "sober128tab.c"
-
-const struct ltc_prng_descriptor sober128_desc = 
-{
-   "sober128", 64,
-    &sober128_start,
-    &sober128_add_entropy,
-    &sober128_ready,
-    &sober128_read,
-    &sober128_done,
-    &sober128_export,
-    &sober128_import,
-    &sober128_test
-};
-
-/* don't change these... */
-#define N                        17
-#define FOLD                      N /* how many iterations of folding to do */
-#define INITKONST        0x6996c53a /* value of KONST to use during key loading */
-#define KEYP                     15 /* where to insert key words */
-#define FOLDP                     4 /* where to insert non-linear feedback */
-
-#define B(x,i) ((unsigned char)(((x) >> (8*i)) & 0xFF))
-
-static ulong32 BYTE2WORD(unsigned char *b)
-{
-   ulong32 t;
-   LOAD32L(t, b);
-   return t;
-}
-
-#define WORD2BYTE(w, b) STORE32L(b, w)
-
-static void XORWORD(ulong32 w, unsigned char *b)
+const struct ltc_prng_descriptor sober128_desc =
 {
-   ulong32 t;
-   LOAD32L(t, b);
-   t ^= w;
-   STORE32L(t, b);
-}
-
-/* give correct offset for the current position of the register,
- * where logically R[0] is at position "zero".
- */
-#define OFF(zero, i) (((zero)+(i)) % N)
-
-/* step the LFSR */
-/* After stepping, "zero" moves right one place */
-#define STEP(R,z) \
-    R[OFF(z,0)] = R[OFF(z,15)] ^ R[OFF(z,4)] ^ (R[OFF(z,0)] << 8) ^ Multab[(R[OFF(z,0)] >> 24) & 0xFF];
-
-static void cycle(ulong32 *R)
-{
-    ulong32 t;
-    int     i;
-
-    STEP(R,0);
-    t = R[0];
-    for (i = 1; i < N; ++i) {
-        R[i-1] = R[i];
-    }
-    R[N-1] = t;
-}
-
-/* Return a non-linear function of some parts of the register.
- */
-#define NLFUNC(c,z) \
-{ \
-    t = c->R[OFF(z,0)] + c->R[OFF(z,16)]; \
-    t ^= Sbox[(t >> 24) & 0xFF]; \
-    t = RORc(t, 8); \
-    t = ((t + c->R[OFF(z,1)]) ^ c->konst) + c->R[OFF(z,6)]; \
-    t ^= Sbox[(t >> 24) & 0xFF]; \
-    t = t + c->R[OFF(z,13)]; \
-}
-
-static ulong32 nltap(struct sober128_prng *c)
-{
-    ulong32 t;
-    NLFUNC(c, 0);
-    return t;
-}
+   "sober128",
+   40,
+   &sober128_start,
+   &sober128_add_entropy,
+   &sober128_ready,
+   &sober128_read,
+   &sober128_done,
+   &sober128_export,
+   &sober128_import,
+   &sober128_test
+};
 
 /**
   Start the PRNG
   @param prng     [out] The PRNG state to initialize
   @return CRYPT_OK if successful
-*/  
+*/
 int sober128_start(prng_state *prng)
 {
-    int                   i;
-    struct sober128_prng *c;
-
-    LTC_ARGCHK(prng != NULL);
-
-    c = &(prng->sober128);
-    
-    /* Register initialised to Fibonacci numbers */
-    c->R[0] = 1;
-    c->R[1] = 1;
-    for (i = 2; i < N; ++i) {
-       c->R[i] = c->R[i-1] + c->R[i-2];
-    }
-    c->konst = INITKONST;
-
-    /* next add_entropy will be the key */
-    c->flag  = 1;
-    c->set   = 0;
-
-    return CRYPT_OK;
-}
-
-/* Save the current register state
- */
-static void s128_savestate(struct sober128_prng *c)
-{
-    int i;
-    for (i = 0; i < N; ++i) {
-        c->initR[i] = c->R[i];
-    }
-}
-
-/* initialise to previously saved register state
- */
-static void s128_reloadstate(struct sober128_prng *c)
-{
-    int i;
-
-    for (i = 0; i < N; ++i) {
-        c->R[i] = c->initR[i];
-    }
-}
-
-/* Initialise "konst"
- */
-static void s128_genkonst(struct sober128_prng *c)
-{
-    ulong32 newkonst;
-
-    do {
-       cycle(c->R);
-       newkonst = nltap(c);
-    } while ((newkonst & 0xFF000000) == 0);
-    c->konst = newkonst;
-}
-
-/* Load key material into the register
- */
-#define ADDKEY(k) \
-   c->R[KEYP] += (k);
-
-#define XORNL(nl) \
-   c->R[FOLDP] ^= (nl);
-
-/* nonlinear diffusion of register for key */
-#define DROUND(z) STEP(c->R,z); NLFUNC(c,(z+1)); c->R[OFF((z+1),FOLDP)] ^= t; 
-static void s128_diffuse(struct sober128_prng *c)
-{
-    ulong32 t;
-    /* relies on FOLD == N == 17! */
-    DROUND(0);
-    DROUND(1);
-    DROUND(2);
-    DROUND(3);
-    DROUND(4);
-    DROUND(5);
-    DROUND(6);
-    DROUND(7);
-    DROUND(8);
-    DROUND(9);
-    DROUND(10);
-    DROUND(11);
-    DROUND(12);
-    DROUND(13);
-    DROUND(14);
-    DROUND(15);
-    DROUND(16);
+   LTC_ARGCHK(prng != NULL);
+   prng->ready = 0;
+   XMEMSET(&prng->sober128.ent, 0, sizeof(prng->sober128.ent));
+   prng->sober128.idx = 0;
+   LTC_MUTEX_INIT(&prng->lock)
+   return CRYPT_OK;
 }
 
 /**
@@ -203,81 +52,63 @@
   @param inlen    Length of the data to add
   @param prng     PRNG state to update
   @return CRYPT_OK if successful
-*/  
+*/
 int sober128_add_entropy(const unsigned char *in, unsigned long inlen, prng_state *prng)
 {
-    struct sober128_prng *c;
-    ulong32               i, k;
-
-    LTC_ARGCHK(in != NULL);
-    LTC_ARGCHK(prng != NULL);
-    c = &(prng->sober128);
+   unsigned char buf[40];
+   unsigned long i;
+   int err;
 
-    if (c->flag == 1) {
-       /* this is the first call to the add_entropy so this input is the key */
-       /* inlen must be multiple of 4 bytes */
-       if ((inlen & 3) != 0) {
-          return CRYPT_INVALID_KEYSIZE;
-       }
-    
-       for (i = 0; i < inlen; i += 4) {
-           k = BYTE2WORD((unsigned char *)&in[i]);
-          ADDKEY(k);
-          cycle(c->R);
-          XORNL(nltap(c));
-       }
-
-       /* also fold in the length of the key */
-       ADDKEY(inlen);
-
-       /* now diffuse */
-       s128_diffuse(c);
+   LTC_ARGCHK(prng != NULL);
+   LTC_ARGCHK(in != NULL);
+   LTC_ARGCHK(inlen > 0);
 
-       s128_genkonst(c);
-       s128_savestate(c);
-       c->nbuf = 0;
-       c->flag = 0;       
-       c->set  = 1;
-    } else {
-       /* ok we are adding an IV then... */
-       s128_reloadstate(c);
-
-       /* inlen must be multiple of 4 bytes */
-       if ((inlen & 3) != 0) {
-          return CRYPT_INVALID_KEYSIZE;
-       }
-    
-       for (i = 0; i < inlen; i += 4) {
-           k = BYTE2WORD((unsigned char *)&in[i]);
-          ADDKEY(k);
-          cycle(c->R);
-          XORNL(nltap(c));
-       }
-
-       /* also fold in the length of the key */
-       ADDKEY(inlen);
-
-       /* now diffuse */
-       s128_diffuse(c);
-       c->nbuf = 0;
-    }
-
-    return CRYPT_OK;
+   LTC_MUTEX_LOCK(&prng->lock);
+   if (prng->ready) {
+      /* sober128_ready() was already called, do "rekey" operation */
+      if ((err = sober128_stream_keystream(&prng->sober128.s, buf, sizeof(buf))) != CRYPT_OK) goto LBL_UNLOCK;
+      for(i = 0; i < inlen; i++) buf[i % sizeof(buf)] ^= in[i];
+      /* key 32 bytes, 20 rounds */
+      if ((err = sober128_stream_setup(&prng->sober128.s, buf, 32)) != CRYPT_OK)     goto LBL_UNLOCK;
+      /* iv 8 bytes */
+      if ((err = sober128_stream_setiv(&prng->sober128.s, buf + 32, 8)) != CRYPT_OK) goto LBL_UNLOCK;
+      /* clear KEY + IV */
+      zeromem(buf, sizeof(buf));
+   }
+   else {
+      /* sober128_ready() was not called yet, add entropy to ent buffer */
+      while (inlen--) prng->sober128.ent[prng->sober128.idx++ % sizeof(prng->sober128.ent)] ^= *in++;
+   }
+   err = CRYPT_OK;
+LBL_UNLOCK:
+   LTC_MUTEX_UNLOCK(&prng->lock);
+   return err;
 }
 
 /**
   Make the PRNG ready to read from
   @param prng   The PRNG to make active
   @return CRYPT_OK if successful
-*/  
+*/
 int sober128_ready(prng_state *prng)
 {
-   return prng->sober128.set == 1 ? CRYPT_OK : CRYPT_ERROR;
-}
+   int err;
+
+   LTC_ARGCHK(prng != NULL);
 
-/* XOR pseudo-random bytes into buffer
- */
-#define SROUND(z) STEP(c->R,z); NLFUNC(c,(z+1)); XORWORD(t, out+(z*4));
+   LTC_MUTEX_LOCK(&prng->lock);
+   if (prng->ready)                                                            { err = CRYPT_OK; goto LBL_UNLOCK; }
+   /* key 32 bytes, 20 rounds */
+   if ((err = sober128_stream_setup(&prng->sober128.s, prng->sober128.ent, 32)) != CRYPT_OK)     goto LBL_UNLOCK;
+   /* iv 8 bytes */
+   if ((err = sober128_stream_setiv(&prng->sober128.s, prng->sober128.ent + 32, 8)) != CRYPT_OK) goto LBL_UNLOCK;
+   XMEMSET(&prng->sober128.ent, 0, sizeof(prng->sober128.ent));
+   prng->sober128.idx = 0;
+   prng->ready = 1;
+LBL_UNLOCK:
+   LTC_MUTEX_UNLOCK(&prng->lock);
+   return err;
+}
 
 /**
   Read from the PRNG
@@ -285,90 +116,33 @@
   @param outlen   Length of output
   @param prng     The active PRNG to read from
   @return Number of octets read
-*/  
+*/
 unsigned long sober128_read(unsigned char *out, unsigned long outlen, prng_state *prng)
 {
-   struct sober128_prng *c;
-   ulong32               t, tlen;
-
-   LTC_ARGCHK(out  != NULL);
-   LTC_ARGCHK(prng != NULL);
-
-#ifdef LTC_VALGRIND
-   zeromem(out, outlen);
-#endif
-
-   c = &(prng->sober128);
-   t = 0;
-   tlen = outlen;
-   
-   /* handle any previously buffered bytes */
-   while (c->nbuf != 0 && outlen != 0) {
-      *out++ ^= c->sbuf & 0xFF;
-       c->sbuf >>= 8;
-       c->nbuf -= 8;
-       --outlen;
-   }
-
-#ifndef LTC_SMALL_CODE
-    /* do lots at a time, if there's enough to do */
-    while (outlen >= N*4) {
-      SROUND(0);
-      SROUND(1);
-      SROUND(2);
-      SROUND(3);
-      SROUND(4);
-      SROUND(5);
-      SROUND(6);
-      SROUND(7);
-      SROUND(8);
-      SROUND(9);
-      SROUND(10);
-      SROUND(11);
-      SROUND(12);
-      SROUND(13);
-      SROUND(14);
-      SROUND(15);
-      SROUND(16);
-      out    += 4*N;
-      outlen -= 4*N;
-    }
-#endif
-
-    /* do small or odd size buffers the slow way */
-    while (4 <= outlen) {
-      cycle(c->R);
-      t = nltap(c);
-      XORWORD(t, out);
-      out    += 4;
-      outlen -= 4;
-    }
-
-    /* handle any trailing bytes */
-    if (outlen != 0) {
-      cycle(c->R);
-      c->sbuf = nltap(c);
-      c->nbuf = 32;
-      while (c->nbuf != 0 && outlen != 0) {
-          *out++ ^= c->sbuf & 0xFF;
-          c->sbuf >>= 8;
-          c->nbuf -= 8;
-          --outlen;
-      }
-    }
-
-    return tlen;
+   if (outlen == 0 || prng == NULL || out == NULL) return 0;
+   LTC_MUTEX_LOCK(&prng->lock);
+   if (!prng->ready) { outlen = 0; goto LBL_UNLOCK; }
+   if (sober128_stream_keystream(&prng->sober128.s, out, outlen) != CRYPT_OK) outlen = 0;
+LBL_UNLOCK:
+   LTC_MUTEX_UNLOCK(&prng->lock);
+   return outlen;
 }
 
 /**
   Terminate the PRNG
   @param prng   The PRNG to terminate
   @return CRYPT_OK if successful
-*/  
+*/
 int sober128_done(prng_state *prng)
 {
+   int err;
    LTC_ARGCHK(prng != NULL);
-   return CRYPT_OK;
+   LTC_MUTEX_LOCK(&prng->lock);
+   prng->ready = 0;
+   err = sober128_stream_done(&prng->sober128.s);
+   LTC_MUTEX_UNLOCK(&prng->lock);
+   LTC_MUTEX_DESTROY(&prng->lock);
+   return err;
 }
 
 /**
@@ -377,124 +151,99 @@
   @param outlen    [in/out] Max size and resulting size of the state
   @param prng      The PRNG to export
   @return CRYPT_OK if successful
-*/  
+*/
 int sober128_export(unsigned char *out, unsigned long *outlen, prng_state *prng)
 {
-   LTC_ARGCHK(outlen != NULL);
-   LTC_ARGCHK(out    != NULL);
+   unsigned long len = sober128_desc.export_size;
+
    LTC_ARGCHK(prng   != NULL);
+   LTC_ARGCHK(out    != NULL);
+   LTC_ARGCHK(outlen != NULL);
 
-   if (*outlen < 64) {
-      *outlen = 64;
+   if (*outlen < len) {
+      *outlen = len;
       return CRYPT_BUFFER_OVERFLOW;
    }
 
-   if (sober128_read(out, 64, prng) != 64) {
+   if (sober128_read(out, len, prng) != len) {
       return CRYPT_ERROR_READPRNG;
    }
-   *outlen = 64;
 
+   *outlen = len;
    return CRYPT_OK;
 }
- 
+
 /**
   Import a PRNG state
   @param in       The PRNG state
   @param inlen    Size of the state
   @param prng     The PRNG to import
   @return CRYPT_OK if successful
-*/  
+*/
 int sober128_import(const unsigned char *in, unsigned long inlen, prng_state *prng)
 {
    int err;
-   LTC_ARGCHK(in   != NULL);
-   LTC_ARGCHK(prng != NULL);
 
-   if (inlen != 64) {
-      return CRYPT_INVALID_ARG;
-   }
-   
-   if ((err = sober128_start(prng)) != CRYPT_OK) {
-      return err;
-   }
-   if ((err = sober128_add_entropy(in, 64, prng)) != CRYPT_OK) {
-      return err;
-   }
-   return sober128_ready(prng);
+   LTC_ARGCHK(prng != NULL);
+   LTC_ARGCHK(in   != NULL);
+   if (inlen < (unsigned long)sober128_desc.export_size) return CRYPT_INVALID_ARG;
+
+   if ((err = sober128_start(prng)) != CRYPT_OK) return err;
+   if ((err = sober128_add_entropy(in, sober128_desc.export_size, prng)) != CRYPT_OK) return err;
+   return CRYPT_OK;
 }
 
 /**
   PRNG self-test
   @return CRYPT_OK if successful, CRYPT_NOP if self-testing has been disabled
-*/  
+*/
 int sober128_test(void)
 {
 #ifndef LTC_TEST
    return CRYPT_NOP;
 #else
-   static const struct { 
-     int keylen, ivlen, len;
-     unsigned char key[16], iv[4], out[20];
-   } tests[] = {
-
-{
-   16, 4, 20,
-
-   /* key */
-   { 0x74, 0x65, 0x73, 0x74, 0x20, 0x6b, 0x65, 0x79, 
-     0x20, 0x31, 0x32, 0x38, 0x62, 0x69, 0x74, 0x73 },
-
-   /* IV */
-   { 0x00, 0x00, 0x00, 0x00 },
-
-   /* expected output */
-   { 0x43, 0x50, 0x0c, 0xcf, 0x89, 0x91, 0x9f, 0x1d,
-     0xaa, 0x37, 0x74, 0x95, 0xf4, 0xb4, 0x58, 0xc2, 
-     0x40, 0x37, 0x8b, 0xbb }
-}
-
-};
-   prng_state    prng;
-   unsigned char dst[20];
-   int           err, x;
+   prng_state st;
+   unsigned char en[] = { 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a,
+                          0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11, 0x12, 0x13, 0x14,
+                          0x15, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e,
+                          0x1f, 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28,
+                          0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, 0x30, 0x31, 0x32 };
+   unsigned char dmp[300];
+   unsigned long dmplen = sizeof(dmp);
+   unsigned char out[500];
+   unsigned char t1[] = { 0x31, 0x82, 0xA7, 0xA5, 0x8B, 0xD7, 0xCB, 0x39, 0x86, 0x1A };
+   unsigned char t2[] = { 0x6B, 0x43, 0x9E, 0xBC, 0xE7, 0x62, 0x9B, 0xE6, 0x9B, 0x83 };
+   unsigned char t3[] = { 0x4A, 0x0E, 0x6C, 0xC1, 0xCF, 0xB4, 0x73, 0x49, 0x99, 0x05 };
+   int err;
 
-   for (x = 0; x < (int)(sizeof(tests)/sizeof(tests[0])); x++) {
-       if ((err = sober128_start(&prng)) != CRYPT_OK) {
-          return err;
-       }
-       if ((err = sober128_add_entropy(tests[x].key, tests[x].keylen, &prng)) != CRYPT_OK) {
-          return err;
-       }
-       /* add IV */
-       if ((err = sober128_add_entropy(tests[x].iv, tests[x].ivlen, &prng)) != CRYPT_OK) {
-          return err;
-       }
+   if ((err = sober128_start(&st)) != CRYPT_OK)                         return err;
+   /* add entropy to uninitialized prng */
+   if ((err = sober128_add_entropy(en, sizeof(en), &st)) != CRYPT_OK)   return err;
+   if ((err = sober128_ready(&st)) != CRYPT_OK)                         return err;
+   if (sober128_read(out, 10, &st) != 10)                               return CRYPT_ERROR_READPRNG; /* 10 bytes for testing */
+   if (compare_testvector(out, 10, t1, sizeof(t1), "SOBER128-PRNG", 1)) return CRYPT_FAIL_TESTVECTOR;
+   if (sober128_read(out, 500, &st) != 500)                             return CRYPT_ERROR_READPRNG; /* skip 500 bytes */
+   /* add entropy to already initialized prng */
+   if ((err = sober128_add_entropy(en, sizeof(en), &st)) != CRYPT_OK)   return err;
+   if (sober128_read(out, 500, &st) != 500)                             return CRYPT_ERROR_READPRNG; /* skip 500 bytes */
+   if ((err = sober128_export(dmp, &dmplen, &st)) != CRYPT_OK)          return err;
+   if (sober128_read(out, 500, &st) != 500)                             return CRYPT_ERROR_READPRNG; /* skip 500 bytes */
+   if (sober128_read(out, 10, &st) != 10)                               return CRYPT_ERROR_READPRNG; /* 10 bytes for testing */
+   if (compare_testvector(out, 10, t2, sizeof(t2), "SOBER128-PRNG", 2)) return CRYPT_FAIL_TESTVECTOR;
+   if ((err = sober128_done(&st)) != CRYPT_OK)                          return err;
+   if ((err = sober128_import(dmp, dmplen, &st)) != CRYPT_OK)           return err;
+   if ((err = sober128_ready(&st)) != CRYPT_OK)                         return err;
+   if (sober128_read(out, 500, &st) != 500)                             return CRYPT_ERROR_READPRNG; /* skip 500 bytes */
+   if (sober128_read(out, 10, &st) != 10)                               return CRYPT_ERROR_READPRNG; /* 10 bytes for testing */
+   if (compare_testvector(out, 10, t3, sizeof(t3), "SOBER128-PRNG", 3)) return CRYPT_FAIL_TESTVECTOR;
+   if ((err = sober128_done(&st)) != CRYPT_OK)                          return err;
 
-       /* ready up */
-       if ((err = sober128_ready(&prng)) != CRYPT_OK) {
-          return err;
-       }
-       XMEMSET(dst, 0, tests[x].len);
-       if (sober128_read(dst, tests[x].len, &prng) != (unsigned long)tests[x].len) {
-          return CRYPT_ERROR_READPRNG;
-       }
-       sober128_done(&prng);
-       if (XMEMCMP(dst, tests[x].out, tests[x].len)) {
-#if 0
-          printf("\n\nLTC_SOBER128 failed, I got:\n"); 
-          for (y = 0; y < tests[x].len; y++) printf("%02x ", dst[y]);
-          printf("\n");
-#endif
-          return CRYPT_FAIL_TESTVECTOR;
-       }
-   }
    return CRYPT_OK;
 #endif
 }
 
 #endif
 
-
-/* $Source$ */
-/* $Revision$ */
-/* $Date$ */
+/* ref:         $Format:%D$ */
+/* git commit:  $Format:%H$ */
+/* commit time: $Format:%ai$ */