Small performance improvement on MIPS

This commit is contained in:
wiire-a 2017-12-20 22:16:21 +01:00
parent da5f0f436f
commit 77fde24c14

View File

@ -142,11 +142,16 @@ struct ralink_randstate {
static unsigned char ralink_randbyte(struct ralink_randstate *state) static unsigned char ralink_randbyte(struct ralink_randstate *state)
{ {
unsigned char r = 0, result; unsigned char r = 0;
if (state->sreg == 0) state->sreg = 1;
for (int i = 0; i < 8; i++) { for (int i = 0; i < 8; i++) {
#if defined(__mips__) || defined(__mips)
uint32_t lsb_mask = -(state->sreg & 1);
state->sreg ^= lsb_mask & 0x80000057;
state->sreg >>= 1;
state->sreg |= lsb_mask & 0x80000000;
r = (r << 1) | (lsb_mask & 1);
#else
unsigned char result;
if (state->sreg & 0x00000001) { if (state->sreg & 0x00000001) {
state->sreg = ((state->sreg ^ 0x80000057) >> 1) | 0x80000000; state->sreg = ((state->sreg ^ 0x80000057) >> 1) | 0x80000000;
result = 1; result = 1;
@ -156,6 +161,7 @@ static unsigned char ralink_randbyte(struct ralink_randstate *state)
result = 0; result = 0;
} }
r = (r << 1) | result; r = (r << 1) | result;
#endif
} }
return r; return r;
} }
@ -269,7 +275,9 @@ static void init_crack_jobs(struct global *wps, int mode)
memcpy(job_control.randr_enonce, wps->e_nonce, WPS_NONCE_LEN); memcpy(job_control.randr_enonce, wps->e_nonce, WPS_NONCE_LEN);
job_control.crack_jobs = malloc(wps->jobs * sizeof (struct crack_job)); job_control.crack_jobs = malloc(wps->jobs * sizeof (struct crack_job));
uint32_t curr = (mode == RTL819x) ? wps->start : 0; uint32_t curr = 0;
if (mode == RTL819x) curr = wps->start;
else if (mode == RT) curr = 1; /* Ralink LFSR jumps from 0 to 1 internally */
int32_t add = (mode == RTL819x) ? -SEEDS_PER_JOB_BLOCK : SEEDS_PER_JOB_BLOCK; int32_t add = (mode == RTL819x) ? -SEEDS_PER_JOB_BLOCK : SEEDS_PER_JOB_BLOCK;
for (i = 0; i < wps->jobs; i++) { for (i = 0; i < wps->jobs; i++) {
job_control.crack_jobs[i].start = (mode == -RTL819x) ? (uint32_t)i + 1 : curr; job_control.crack_jobs[i].start = (mode == -RTL819x) ? (uint32_t)i + 1 : curr;
@ -1102,7 +1110,7 @@ usage_err:
unsigned lfsr = bit_revert(wps->nonce_seed); unsigned lfsr = bit_revert(wps->nonce_seed);
int k = 8 * 32; int k = 8 * 32;
while (k--) { while (k--) {
unsigned int lsb_mask = ~(lfsr & 1) + 1; unsigned int lsb_mask = -(lfsr & 1);
lfsr ^= lsb_mask & 0xd4000003; lfsr ^= lsb_mask & 0xd4000003;
lfsr >>= 1; lfsr >>= 1;
lfsr |= lsb_mask & 0x80000000; lfsr |= lsb_mask & 0x80000000;