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Diffstat (limited to 'libdnet-stripped/src/rand.c')
| -rw-r--r-- | libdnet-stripped/src/rand.c | 208 |
1 files changed, 208 insertions, 0 deletions
diff --git a/libdnet-stripped/src/rand.c b/libdnet-stripped/src/rand.c new file mode 100644 index 0000000..9095ad8 --- /dev/null +++ b/libdnet-stripped/src/rand.c @@ -0,0 +1,208 @@ +/* + * rand.c + * + * Pseudorandom number generation, based on OpenBSD arc4random(). + * + * Copyright (c) 2000 Dug Song <dugsong@monkey.org> + * Copyright (c) 1996 David Mazieres <dm@lcs.mit.edu> + * + * $Id: rand.c 587 2005-02-15 06:37:07Z dugsong $ + */ + +#include "config.h" + +#ifdef _WIN32 +/* XXX */ +# undef _WIN32_WINNT +# define _WIN32_WINNT _WIN32_WINNT_WIN7 +# include <bcrypt.h> +# pragma comment(lib, "bcrypt.lib") +# define inline __inline +#else +# include <sys/types.h> +# include <sys/time.h> +# include <unistd.h> +#endif +#include <fcntl.h> +#include <stdlib.h> +#include <string.h> + +#include "dnet.h" + +struct rand_handle { + uint8_t i; + uint8_t j; + uint8_t s[256]; + u_char *tmp; + int tmplen; +}; + +static inline void +rand_init(rand_t *rand) +{ + int i; + + for (i = 0; i < 256; i++) + rand->s[i] = i; + rand->i = rand->j = 0; +} + +static inline void +rand_addrandom(rand_t *rand, u_char *buf, int len) +{ + int i; + uint8_t si; + + rand->i--; + for (i = 0; i < 256; i++) { + rand->i = (rand->i + 1); + si = rand->s[rand->i]; + rand->j = (rand->j + si + buf[i % len]); + rand->s[rand->i] = rand->s[rand->j]; + rand->s[rand->j] = si; + } + rand->j = rand->i; +} + +rand_t * +rand_open(void) +{ + rand_t *r; + u_char seed[256]; +#ifdef _WIN32 + if (STATUS_SUCCESS != BCryptGenRandom(NULL, seed, sizeof(seed), BCRYPT_USE_SYSTEM_PREFERRED_RNG)) + return NULL; +#else + struct timeval *tv = (struct timeval *)seed; + int fd; + + if ((fd = open("/dev/arandom", O_RDONLY)) != -1 || + (fd = open("/dev/urandom", O_RDONLY)) != -1) { + read(fd, seed + sizeof(*tv), sizeof(seed) - sizeof(*tv)); + close(fd); + } + gettimeofday(tv, NULL); +#endif + if ((r = malloc(sizeof(*r))) != NULL) { + rand_init(r); + rand_addrandom(r, seed, 128); + rand_addrandom(r, seed + 128, 128); + r->tmp = NULL; + r->tmplen = 0; + } + return (r); +} + +static uint8_t +rand_getbyte(rand_t *r) +{ + uint8_t si, sj; + + r->i = (r->i + 1); + si = r->s[r->i]; + r->j = (r->j + si); + sj = r->s[r->j]; + r->s[r->i] = sj; + r->s[r->j] = si; + return (r->s[(si + sj) & 0xff]); +} + +int +rand_get(rand_t *r, void *buf, size_t len) +{ + u_char *p; + u_int i; + + for (p = buf, i = 0; i < len; i++) { + p[i] = rand_getbyte(r); + } + return (0); +} + +int +rand_set(rand_t *r, const void *buf, size_t len) +{ + rand_init(r); + rand_addrandom(r, (u_char *)buf, len); + rand_addrandom(r, (u_char *)buf, len); + return (0); +} + +int +rand_add(rand_t *r, const void *buf, size_t len) +{ + rand_addrandom(r, (u_char *)buf, len); + return (0); +} + +uint8_t +rand_uint8(rand_t *r) +{ + return (rand_getbyte(r)); +} + +uint16_t +rand_uint16(rand_t *r) +{ + uint16_t val; + + val = rand_getbyte(r) << 8; + val |= rand_getbyte(r); + return (val); +} + +uint32_t +rand_uint32(rand_t *r) +{ + uint32_t val; + + val = rand_getbyte(r) << 24; + val |= rand_getbyte(r) << 16; + val |= rand_getbyte(r) << 8; + val |= rand_getbyte(r); + return (val); +} + +int +rand_shuffle(rand_t *r, void *base, size_t nmemb, size_t size) +{ + u_char *save, *src, *dst, *start = (u_char *)base; + u_int i, j; + + if (nmemb < 2) + return (0); + + if ((u_int)r->tmplen < size) { + if (r->tmp == NULL) { + if ((save = malloc(size)) == NULL) + return (-1); + } else if ((save = realloc(r->tmp, size)) == NULL) + return (-1); + + r->tmp = save; + r->tmplen = size; + } else + save = r->tmp; + + for (i = 0; i < nmemb; i++) { + if ((j = rand_uint32(r) % (nmemb - 1)) != i) { + src = start + (size * i); + dst = start + (size * j); + memcpy(save, dst, size); + memcpy(dst, src, size); + memcpy(src, save, size); + } + } + return (0); +} + +rand_t * +rand_close(rand_t *r) +{ + if (r != NULL) { + if (r->tmp != NULL) + free(r->tmp); + free(r); + } + return (NULL); +} |