3 * Various handy server-only utilities
5 * (c) 2001 Straylight/Edgeware
8 /*----- Licensing notice --------------------------------------------------*
10 * This file is part of Trivial IP Encryption (TrIPE).
12 * TrIPE is free software: you can redistribute it and/or modify it under
13 * the terms of the GNU General Public License as published by the Free
14 * Software Foundation; either version 3 of the License, or (at your
15 * option) any later version.
17 * TrIPE is distributed in the hope that it will be useful, but WITHOUT
18 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
19 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
22 * You should have received a copy of the GNU General Public License
23 * along with TrIPE. If not, see <https://www.gnu.org/licenses/>.
26 /*----- Header files ------------------------------------------------------*/
30 /*----- Global variables --------------------------------------------------*/
32 octet buf_i[PKBUFSZ], buf_o[PKBUFSZ], buf_t[PKBUFSZ], buf_u[PKBUFSZ];
34 /*----- Sequence numbers --------------------------------------------------*/
36 /* --- @seq_reset@ --- *
38 * Arguments: @seqwin *s@ = sequence-checking window
42 * Use: Resets a sequence number window.
45 void seq_reset(seqwin *s) { s->seq = 0; s->win = 0; }
47 /* --- @seq_check@ --- *
49 * Arguments: @seqwin *s@ = sequence-checking window
50 * @uint32 q@ = sequence number to check
51 * @const char *service@ = service to report message from
53 * Returns: Zero on success, nonzero if the sequence number was bad.
55 * Use: Checks a sequence number against the window, updating things
59 int seq_check(seqwin *s, uint32 q, const char *service)
65 a_warn(service, "replay", "old-sequence", A_END);
68 if (q >= s->seq + SEQ_WINSZ) {
69 n = q - (s->seq + SEQ_WINSZ - 1);
76 qbit = 1 << (q - s->seq);
78 a_warn(service, "replay", "duplicated-sequence", A_END);
85 /*----- Rate limiting -----------------------------------------------------*/
87 /* --- @ratelim_init@ --- *
89 * Arguments: @ratelim *r@ = rate-limiting state to fill in
90 * @unsigned persec@ = credit to accumulate per second
91 * @unsigned max@ = maximum credit to retain
95 * Use: Initialize a rate-limiting state.
98 void ratelim_init(ratelim *r, unsigned persec, unsigned max)
102 gettimeofday(&r->when, 0);
105 /* --- @ratelim_withdraw@ --- *
107 * Arguments: @ratelim *r@ = rate-limiting state
108 * @unsigned n@ = credit to withdraw
110 * Returns: Zero if successful; @-1@ if there is unsufficient credit
112 * Use: Updates the state with any accumulated credit. Then, if
113 * there there are more than @n@ credits available, withdraw @n@
114 * and return successfully; otherwise, report failure.
117 int ratelim_withdraw(ratelim *r, unsigned n)
119 struct timeval now, delta;
122 gettimeofday(&now, 0);
123 TV_SUB(&delta, &now, &r->when);
124 d = (unsigned long)r->persec*delta.tv_sec +
125 (unsigned long)r->persec*delta.tv_usec/MILLION;
126 if (d < r->max - r->n) r->n += d;
130 if (n > r->n) return (-1);
131 else { r->n -= n; return (0); }
134 /*----- Random odds and sods ----------------------------------------------*/
136 /* --- @timestr@ --- *
138 * Arguments: @time_t t@ = a time to convert
140 * Returns: A pointer to a textual representation of the time.
142 * Use: Converts a time to a textual representation. Corrupts
146 const char *timestr(time_t t)
152 strftime((char *)buf_u, sizeof(buf_u), "%Y-%m-%dT%H:%M:%S", tm);
153 return ((const char *)buf_u);
156 /* --- @mystrieq@ --- *
158 * Arguments: @const char *x, *y@ = two strings
160 * Returns: True if @x@ and @y are equal, up to case.
163 int mystrieq(const char *x, const char *y)
166 if (!*x && !*y) return (1);
167 if (tolower((unsigned char)*x) != tolower((unsigned char)*y))
173 /* --- @addrsz@ --- *
175 * Arguments: @const addr *a@ = a network address
177 * Returns: The size of the address, for passing into the sockets API.
180 socklen_t addrsz(const addr *a)
182 switch (a->sa.sa_family) {
183 case AF_INET: return (sizeof(a->sin));
188 /*----- That's all, folks -------------------------------------------------*/