/* * Generic address resultion entity * * Authors: * net_random Alan Cox * net_ratelimit Andy Kleen * in{4,6}_pton YOSHIFUJI Hideaki, Copyright (C)2006 USAGI/WIDE Project * * Created by Alexey Kuznetsov * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* This is a maximally equidistributed combined Tausworthe generator based on code from GNU Scientific Library 1.5 (30 Jun 2004) x_n = (s1_n ^ s2_n ^ s3_n) s1_{n+1} = (((s1_n & 4294967294) <<12) ^ (((s1_n <<13) ^ s1_n) >>19)) s2_{n+1} = (((s2_n & 4294967288) << 4) ^ (((s2_n << 2) ^ s2_n) >>25)) s3_{n+1} = (((s3_n & 4294967280) <<17) ^ (((s3_n << 3) ^ s3_n) >>11)) The period of this generator is about 2^88. From: P. L'Ecuyer, "Maximally Equidistributed Combined Tausworthe Generators", Mathematics of Computation, 65, 213 (1996), 203--213. This is available on the net from L'Ecuyer's home page, http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps ftp://ftp.iro.umontreal.ca/pub/simulation/lecuyer/papers/tausme.ps There is an erratum in the paper "Tables of Maximally Equidistributed Combined LFSR Generators", Mathematics of Computation, 68, 225 (1999), 261--269: http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps ... the k_j most significant bits of z_j must be non- zero, for each j. (Note: this restriction also applies to the computer code given in [4], but was mistakenly not mentioned in that paper.) This affects the seeding procedure by imposing the requirement s1 > 1, s2 > 7, s3 > 15. */ struct nrnd_state { u32 s1, s2, s3; }; static DEFINE_PER_CPU(struct nrnd_state, net_rand_state); static u32 __net_random(struct nrnd_state *state) { #define TAUSWORTHE(s,a,b,c,d) ((s&c)<>b) state->s1 = TAUSWORTHE(state->s1, 13, 19, 4294967294UL, 12); state->s2 = TAUSWORTHE(state->s2, 2, 25, 4294967288UL, 4); state->s3 = TAUSWORTHE(state->s3, 3, 11, 4294967280UL, 17); return (state->s1 ^ state->s2 ^ state->s3); } static void __net_srandom(struct nrnd_state *state, unsigned long s) { if (s == 0) s = 1; /* default seed is 1 */ #define LCG(n) (69069 * n) state->s1 = LCG(s); state->s2 = LCG(state->s1); state->s3 = LCG(state->s2); /* "warm it up" */ __net_random(state); __net_random(state); __net_random(state); __net_random(state); __net_random(state); __net_random(state); } unsigned long net_random(void) { unsigned long r; struct nrnd_state *state = &get_cpu_var(net_rand_state); r = __net_random(state); put_cpu_var(state); return r; } void net_srandom(unsigned long entropy) { struct nrnd_state *state = &get_cpu_var(net_rand_state); __net_srandom(state, state->s1^entropy); put_cpu_var(state); } void __init net_random_init(void) { int i; for_each_possible_cpu(i) { struct nrnd_state *state = &per_cpu(net_rand_state,i); __net_srandom(state, i+jiffies); } } static int net_random_reseed(void) { int i; unsigned long seed; for_each_possible_cpu(i) { struct nrnd_state *state = &per_cpu(net_rand_state,i); get_random_bytes(&seed, sizeof(seed)); __net_srandom(state, seed); } return 0; } late_initcall(net_random_reseed); int net_msg_cost = 5*HZ; int net_msg_burst = 10; /* * All net warning printk()s should be guarded by this function. */ int net_ratelimit(void) { return __printk_ratelimit(net_msg_cost, net_msg_burst); } EXPORT_SYMBOL(net_random); EXPORT_SYMBOL(net_ratelimit); EXPORT_SYMBOL(net_srandom); /* * Convert an ASCII string to binary IP. * This is outside of net/ipv4/ because various code that uses IP addresses * is otherwise not dependent on the TCP/IP stack. */ __be32 in_aton(const char *str) { unsigned long l; unsigned int val; int i; l = 0; for (i = 0; i < 4; i++) { l <<= 8; if (*str != '\0') { val = 0; while (*str != '\0' && *str != '.' && *str != '\n') { val *= 10; val += *str - '0'; str++; } l |= val; if (*str != '\0') str++; } } return(htonl(l)); } EXPORT_SYMBOL(in_aton); #define IN6PTON_XDIGIT 0x00010000 #define IN6PTON_DIGIT 0x00020000 #define IN6PTON_COLON_MASK 0x00700000 #define IN6PTON_COLON_1 0x00100000 /* single : requested */ #define IN6PTON_COLON_2 0x00200000 /* second : requested */ #define IN6PTON_COLON_1_2 0x00400000 /* :: requested */ #define IN6PTON_DOT 0x00800000 /* . */ #define IN6PTON_DELIM 0x10000000 #define IN6PTON_NULL 0x20000000 /* first/tail */ #define IN6PTON_UNKNOWN 0x40000000 static inline int digit2bin(char c, char delim) { if (c == delim || c == '\0') return IN6PTON_DELIM; if (c == '.') return IN6PTON_DOT; if (c >= '0' && c <= '9') return (IN6PTON_DIGIT | (c - '0')); return IN6PTON_UNKNOWN; } static inline int xdigit2bin(char c, char delim) { if (c == delim || c == '\0') return IN6PTON_DELIM; if (c == ':') return IN6PTON_COLON_MASK; if (c == '.') return IN6PTON_DOT; if (c >= '0' && c <= '9') return (IN6PTON_XDIGIT | IN6PTON_DIGIT| (c - '0')); if (c >= 'a' && c <= 'f') return (IN6PTON_XDIGIT | (c - 'a' + 10)); if (c >= 'A' && c <= 'F') return (IN6PTON_XDIGIT | (c - 'A' + 10)); return IN6PTON_UNKNOWN; } int in4_pton(const char *src, int srclen, u8 *dst, char delim, const char **end) { const char *s; u8 *d; u8 dbuf[4]; int ret = 0; int i; int w = 0; if (srclen < 0) srclen = strlen(src); s = src; d = dbuf; i = 0; while(1) { int c; c = xdigit2bin(srclen > 0 ? *s : '\0', delim); if (!(c & (IN6PTON_DIGIT | IN6PTON_DOT | IN6PTON_DELIM))) { goto out; } if (c & (IN6PTON_DOT | IN6PTON_DELIM)) { if (w == 0) goto out; *d++ = w & 0xff; w = 0; i++; if (c & IN6PTON_DELIM) { if (i != 4) goto out; break; } goto cont; } w = (w * 10) + c; if ((w & 0xffff) > 255) { goto out; } cont: if (i >= 4) goto out; s++; srclen--; } ret = 1; memcpy(dst, dbuf, sizeof(dbuf)); out: if (end) *end = s; return ret; } EXPORT_SYMBOL(in4_pton); int in6_pton(const char *src, int srclen, u8 *dst, char delim, const char **end) { const char *s, *tok = NULL; u8 *d, *dc = NULL; u8 dbuf[16]; int ret = 0; int i; int state = IN6PTON_COLON_1_2 | IN6PTON_XDIGIT | IN6PTON_NULL; int w = 0; memset(dbuf, 0, sizeof(dbuf)); s = src; d = dbuf; if (srclen < 0) srclen = strlen(src); while (1) { int c; c = xdigit2bin(srclen > 0 ? *s : '\0', delim); if (!(c & state)) goto out; if (c & (IN6PTON_DELIM | IN6PTON_COLON_MASK)) { /* process one 16-bit word */ if (!(state & IN6PTON_NULL)) { *d++ = (w >> 8) & 0xff; *d++ = w & 0xff; } w = 0; if (c & IN6PTON_DELIM) { /* We've processed last word */ break; } /* * COLON_1 => XDIGIT * COLON_2 => XDIGIT|DELIM * COLON_1_2 => COLON_2 */ switch (state & IN6PTON_COLON_MASK) { case IN6PTON_COLON_2: dc = d; state = IN6PTON_XDIGIT | IN6PTON_DELIM; if (dc - dbuf >= sizeof(dbuf)) state |= IN6PTON_NULL; break; case IN6PTON_COLON_1|IN6PTON_COLON_1_2: state = IN6PTON_XDIGIT | IN6PTON_COLON_2; break; case IN6PTON_COLON_1: state = IN6PTON_XDIGIT; break; case IN6PTON_COLON_1_2: state = IN6PTON_COLON_2; break; default: state = 0; } tok = s + 1; goto cont; } if (c & IN6PTON_DOT) { ret = in4_pton(tok ? tok : s, srclen + (int)(s - tok), d, delim, &s); if (ret > 0) { d += 4; break; } goto out; } w = (w << 4) | (0xff & c); state = IN6PTON_COLON_1 | IN6PTON_DELIM; if (!(w & 0xf000)) { state |= IN6PTON_XDIGIT; } if (!dc && d + 2 < dbuf + sizeof(dbuf)) { state |= IN6PTON_COLON_1_2; state &= ~IN6PTON_DELIM; } if (d + 2 >= dbuf + sizeof(dbuf)) { state &= ~(IN6PTON_COLON_1|IN6PTON_COLON_1_2); } cont: if ((dc && d + 4 < dbuf + sizeof(dbuf)) || d + 4 == dbuf + sizeof(dbuf)) { state |= IN6PTON_DOT; } if (d >= dbuf + sizeof(dbuf)) { state &= ~(IN6PTON_XDIGIT|IN6PTON_COLON_MASK); } s++; srclen--; } i = 15; d--; if (dc) { while(d >= dc) dst[i--] = *d--; while(i >= dc - dbuf) dst[i--] = 0; while(i >= 0) dst[i--] = *d--; } else memcpy(dst, dbuf, sizeof(dbuf)); ret = 1; out: if (end) *end = s; return ret; } EXPORT_SYMBOL(in6_pton);