From d2e7ffaaa132b7e2ab425172fd9b673a58b7481e Mon Sep 17 00:00:00 2001 From: wiire-a Date: Wed, 8 Nov 2017 21:58:10 +0100 Subject: [PATCH] Removed boilerplate code from random_r.c Removed all the code non relevant for the current implementation. This should make a noticeable difference in speed and possibly allow the compiler to optimize even more. --- src/pixiewps.c | 4 +- src/random_r.c | 306 ++++++++----------------------------------------- 2 files changed, 48 insertions(+), 262 deletions(-) diff --git a/src/pixiewps.c b/src/pixiewps.c index e53244a..3e81293 100644 --- a/src/pixiewps.c +++ b/src/pixiewps.c @@ -100,7 +100,7 @@ static void *crack_thread(void *arg) { uint32_t seed = j->start; uint32_t limit = job_control.end; - m_initstate_r(seed, rand_statebuf, 128, &buf); + m_initstate_r(seed, rand_statebuf, &buf); int32_t res = 0; while (!job_control.nonce_seed) { @@ -897,7 +897,7 @@ usage_err: struct m_random_data *buf = calloc(1, sizeof(struct m_random_data)); char *rand_statebuf = calloc(1, 128); - m_initstate_r(nonce_seed, rand_statebuf, 128, buf); + m_initstate_r(nonce_seed, rand_statebuf, buf); if (nonce_seed) { /* Seed found */ int32_t res; diff --git a/src/random_r.c b/src/random_r.c index b4b6e7e..3affa14 100644 --- a/src/random_r.c +++ b/src/random_r.c @@ -23,22 +23,21 @@ */ /* -* This file is part of pixiewps and was modified -*/ + * This file is part of pixiewps and was modified + */ #include #include #include #include -/* #include */ #if defined(__unix__) || (defined(__APPLE__) && defined(__MACH__)) -#include -#if defined(BSD) || defined(__APPLE__) && defined(__MACH__) +# include +# if defined(BSD) || defined(__APPLE__) && defined(__MACH__) /* Nothing to include */ #else -#include -#endif +# include +# endif #endif #include @@ -47,100 +46,18 @@ struct m_random_data { int32_t *fptr; /* Front pointer */ int32_t *rptr; /* Rear pointer */ int32_t *state; /* Array of state values */ - int rand_type; /* Type of random number generator */ - int rand_deg; /* Degree of random number generator */ - int rand_sep; /* Distance between front and rear */ int32_t *end_ptr; /* Pointer behind state table */ }; -/* An improved random number generation package. In addition to the standard - rand()/srand() like interface, this package also has a special state info - interface. The initstate() routine is called with a seed, an array of - bytes, and a count of how many bytes are being passed in; this array is - then initialized to contain information for random number generation with - that much state information. Good sizes for the amount of state - information are 32, 64, 128, and 256 bytes. The state can be switched by - calling the setstate() function with the same array as was initialized - with initstate(). By default, the package runs with 128 bytes of state - information and generates far better random numbers than a linear - congruential generator. If the amount of state information is less than - 32 bytes, a simple linear congruential R.N.G. is used. Internally, the - state information is treated as an array of longs; the zeroth element of - the array is the type of R.N.G. being used (small integer); the remainder - of the array is the state information for the R.N.G. Thus, 32 bytes of - state information will give 7 longs worth of state information, which will - allow a degree seven polynomial. (Note: The zeroth word of state - information also has some other information stored in it; see setstate - for details). The random number generation technique is a linear feedback - shift register approach, employing trinomials (since there are fewer terms - to sum up that way). In this approach, the least significant bit of all - the numbers in the state table will act as a linear feedback shift register, - and will have period 2^deg - 1 (where deg is the degree of the polynomial - being used, assuming that the polynomial is irreducible and primitive). - The higher order bits will have longer periods, since their values are - also influenced by pseudo-random carries out of the lower bits. The - total period of the generator is approximately deg*(2**deg - 1); thus - doubling the amount of state information has a vast influence on the - period of the generator. Note: The deg*(2**deg - 1) is an approximation - only good for large deg, when the period of the shift register is the - dominant factor. With deg equal to seven, the period is actually much - longer than the 7*(2**7 - 1) predicted by this formula. */ - -/* For each of the currently supported random number generators, we have a - break value on the amount of state information (you need at least this many - bytes of state info to support this random number generator), a degree for - the polynomial (actually a trinomial) that the R.N.G. is based on, and - separation between the two lower order coefficients of the trinomial. */ - -/* Linear congruential */ -#define TYPE_0 0 -#define BREAK_0 8 -#define DEG_0 0 -#define SEP_0 0 - -/* x**7 + x**3 + 1 */ -#define TYPE_1 1 -#define BREAK_1 32 -#define DEG_1 7 -#define SEP_1 3 - -/* x**15 + x + 1 */ -#define TYPE_2 2 -#define BREAK_2 64 -#define DEG_2 15 -#define SEP_2 1 - /* x**31 + x**3 + 1 */ -#define TYPE_3 3 -#define BREAK_3 128 -#define DEG_3 31 -#define SEP_3 3 +#define TYPE_3 3 +#define BREAK_3 128 +#define DEG_3 31 +#define SEP_3 3 -/* x**63 + x + 1 */ -#define TYPE_4 4 -#define BREAK_4 256 -#define DEG_4 63 -#define SEP_4 1 +#define MAX_TYPES 5 /* Max number of types */ -/* Array versions of the above information to make code run faster. - Relies on fact that TYPE_i == i */ - -#define MAX_TYPES 5 /* Max number of types above */ - -struct m_random_poly_info { - /* smallint seps[MAX_TYPES]; */ - /* smallint degrees[MAX_TYPES]; */ - unsigned char seps[MAX_TYPES]; - unsigned char degrees[MAX_TYPES]; -}; - -static const struct m_random_poly_info random_poly_info = { - {SEP_0, SEP_1, SEP_2, SEP_3, SEP_4}, - {DEG_0, DEG_1, DEG_2, DEG_3, DEG_4} -}; - -/* If we are using the trivial TYPE_0 R.N.G., just do the old linear - congruential bit. Otherwise, we do our fancy trinomial stuff, which is the +/* We do our fancy trinomial stuff, which is the same in all the other cases due to all the global variables that have been set up. The basic operation is to add the number at the rear pointer into the one at the front pointer. Then both pointers are advanced to the next @@ -149,92 +66,54 @@ static const struct m_random_poly_info random_poly_info = { Note: The code takes advantage of the fact that both the front and rear pointers can't wrap on the same call by not testing the rear pointer if the front one has wrapped. Returns a 31-bit random number. */ - void m_random_r(struct m_random_data *buf, int32_t *result) { - int32_t *state; + int32_t *state = buf->state; + int32_t *fptr = buf->fptr; + int32_t *rptr = buf->rptr; + int32_t *end_ptr = buf->end_ptr; + int32_t val = *fptr += *rptr; - /* if (buf == NULL || result == NULL) */ - /* goto fail; */ - - state = buf->state; - - if (buf->rand_type == TYPE_0) { - int32_t val = state[0]; - val = ((state[0] * 1103515245) + 12345) & 0x7fffffff; - state[0] = val; - *result = val; - } else { - int32_t *fptr = buf->fptr; - int32_t *rptr = buf->rptr; - int32_t *end_ptr = buf->end_ptr; - int32_t val; - - val = *fptr += *rptr; - - /* Chucking least random bit. */ - *result = (val >> 1) & 0x7fffffff; - ++fptr; - if (fptr >= end_ptr) { - fptr = state; - ++rptr; - } else { - ++rptr; - if (rptr >= end_ptr) - rptr = state; - } - buf->fptr = fptr; - buf->rptr = rptr; + /* Chucking least random bit. */ + *result = (val >> 1) & 0x7fffffff; + ++fptr; + if (fptr >= end_ptr) { + fptr = state; + ++rptr; } - /* return 0; */ - - /* fail: */ - /* __set_errno (EINVAL); */ - /* return -1; */ + else { + ++rptr; + if (rptr >= end_ptr) + rptr = state; + } + buf->fptr = fptr; + buf->rptr = rptr; } -/* libc_hidden_def(random_r) */ -/* Initialize the random number generator based on the given seed. If the - type is the trivial no-state-information type, just remember the seed. - Otherwise, initializes state[] based on the given "seed" via a linear +/* Initializes state[] based on the given "seed" via a linear congruential generator. Then, the pointers are set to known locations that are exactly rand_sep places apart. Lastly, it cycles the state information a given number of times to get rid of any initial dependencies introduced by the L.C.R.N.G. Note that the initialization of randtbl[] for default usage relies on values produced by this routine. */ -int m_srandom_r(unsigned int seed, struct m_random_data *buf) +void m_srandom_r(unsigned int seed, struct m_random_data *buf) { - int type; - int32_t *state; - long int i; long int word; + int i, kc; int32_t *dst; - int kc; + int32_t *state = buf->state; - if (buf == NULL) - goto fail; - - type = buf->rand_type; - if ((unsigned int)type >= MAX_TYPES) - goto fail; - - state = buf->state; - - /* We must make sure the seed is not 0. Take arbitrarily 1 in this case. */ - if (seed == 0) + /* We must make sure the seed is not 0. Take arbitrarily 1 in this case. */ + if (seed == 0) seed = 1; state[0] = seed; - if (type == TYPE_0) - goto done; - dst = state; word = seed; - kc = buf->rand_deg; - for (i = 1; i < kc; ++i) { + for (i = 1; i < DEG_3; ++i) { /* This does: - state[i] = (16807 * state[i - 1]) % 2147483647; - but avoids overflowing 31 bits. */ + state[i] = (16807 * state[i - 1]) % 2147483647; + but avoids overflowing 31 bits */ long int hi = word / 127773; long int lo = word % 127773; word = 16807 * lo - 2836 * hi; @@ -243,21 +122,14 @@ int m_srandom_r(unsigned int seed, struct m_random_data *buf) *++dst = word; } - buf->fptr = &state[buf->rand_sep]; + buf->fptr = &state[SEP_3]; buf->rptr = &state[0]; - kc *= 10; + kc = DEG_3 * 10; while (--kc >= 0) { int32_t discard; (void)m_random_r(buf, &discard); } - -done: - return 0; - -fail: - return -1; } -/* libc_hidden_def(srandom_r) */ /* Initialize the state information in the given array of N bytes for future random number generation. Based on the number of bytes we @@ -270,104 +142,18 @@ fail: Note: The first thing we do is save the current state, if any, just like setstate so that it doesn't matter when initstate is called. Returns a pointer to the old state. */ -int m_initstate_r(unsigned int seed, char *arg_state, size_t n, struct m_random_data *buf) +void m_initstate_r(unsigned int seed, char *arg_state, struct m_random_data *buf) { int type; int degree; int separation; - int32_t *state; + int32_t *state = &((int32_t *)arg_state)[1]; /* First location */ - if (buf == NULL) - goto fail; - - if (n >= BREAK_3) - type = n < BREAK_4 ? TYPE_3 : TYPE_4; - else if (n < BREAK_1) { - if (n < BREAK_0) { - /* __set_errno (EINVAL); */ - goto fail; - } - type = TYPE_0; - } - else - type = n < BREAK_2 ? TYPE_1 : TYPE_2; - - degree = random_poly_info.degrees[type]; - separation = random_poly_info.seps[type]; - - buf->rand_type = type; - - buf->rand_sep = separation; - buf->rand_deg = degree; - state = &((int32_t *)arg_state)[1]; /* First location. */ - - /* Must set END_PTR before srandom. */ - buf->end_ptr = &state[degree]; + /* Must set END_PTR before srandom */ + buf->end_ptr = &state[DEG_3]; buf->state = state; m_srandom_r(seed, buf); - state[-1] = TYPE_0; - if (type != TYPE_0) - state[-1] = (buf->rptr - state) * MAX_TYPES + type; - - return 0; - -fail: - /* __set_errno (EINVAL); */ - return -1; + state[-1] = (buf->rptr - state) * MAX_TYPES + TYPE_3; } -/* libc_hidden_def(initstate_r) */ - -/* Restore the state from the given state array. - Note: It is important that we also remember the locations of the pointers - in the current state information, and restore the locations of the pointers - from the old state information. This is done by multiplexing the pointer - location into the zeroth word of the state information. Note that due - to the order in which things are done, it is OK to call setstate with the - same state as the current state - Returns a pointer to the old state information. */ -int m_setstate_r(char *arg_state, struct m_random_data *buf) -{ - int32_t *new_state = 1 + (int32_t *)arg_state; - int type; - int old_type; - int32_t *old_state; - int degree; - int separation; - - if (arg_state == NULL || buf == NULL) - goto fail; - - old_type = buf->rand_type; - old_state = buf->state; - if (old_type == TYPE_0) - old_state[-1] = TYPE_0; - else - old_state[-1] = (MAX_TYPES * (buf->rptr - old_state)) + old_type; - - type = new_state[-1] % MAX_TYPES; - if (type < TYPE_0 || type > TYPE_4) - goto fail; - - buf->rand_deg = degree = random_poly_info.degrees[type]; - buf->rand_sep = separation = random_poly_info.seps[type]; - buf->rand_type = type; - - if (type != TYPE_0) { - int rear = new_state[-1] / MAX_TYPES; - buf->rptr = &new_state[rear]; - buf->fptr = &new_state[(rear + separation) % degree]; - } - buf->state = new_state; - - /* Set end_ptr too. */ - buf->end_ptr = &new_state[degree]; - - return 0; - -fail: - /* __set_errno (EINVAL); */ - return -1; -} -/* libc_hidden_def(setstate_r) */