| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * $Id$ |
| 4 | * |
| 5 | * Various handy server-only utilities |
| 6 | * |
| 7 | * (c) 2001 Straylight/Edgeware |
| 8 | */ |
| 9 | |
| 10 | /*----- Licensing notice --------------------------------------------------* |
| 11 | * |
| 12 | * This file is part of Trivial IP Encryption (TrIPE). |
| 13 | * |
| 14 | * TrIPE is free software; you can redistribute it and/or modify |
| 15 | * it under the terms of the GNU General Public License as published by |
| 16 | * the Free Software Foundation; either version 2 of the License, or |
| 17 | * (at your option) any later version. |
| 18 | * |
| 19 | * TrIPE is distributed in the hope that it will be useful, |
| 20 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 22 | * GNU General Public License for more details. |
| 23 | * |
| 24 | * You should have received a copy of the GNU General Public License |
| 25 | * along with TrIPE; if not, write to the Free Software Foundation, |
| 26 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| 27 | */ |
| 28 | |
| 29 | /*----- Header files ------------------------------------------------------*/ |
| 30 | |
| 31 | #include "tripe.h" |
| 32 | |
| 33 | /*----- Global variables --------------------------------------------------*/ |
| 34 | |
| 35 | octet buf_i[PKBUFSZ], buf_o[PKBUFSZ], buf_t[PKBUFSZ]; |
| 36 | |
| 37 | /*----- Main code ---------------------------------------------------------*/ |
| 38 | |
| 39 | /* --- @mpstr@ --- * |
| 40 | * |
| 41 | * Arguments: @mp *m@ = a multiprecision integer |
| 42 | * |
| 43 | * Returns: A pointer to the integer's textual representation. |
| 44 | * |
| 45 | * Use: Converts a multiprecision integer to a string. Corrupts |
| 46 | * @buf_t@. |
| 47 | */ |
| 48 | |
| 49 | const char *mpstr(mp *m) |
| 50 | { |
| 51 | if (mp_writestring(m, (char *)buf_t, sizeof(buf_t), 10)) |
| 52 | return ("<failed>"); |
| 53 | return ((const char *)buf_t); |
| 54 | } |
| 55 | |
| 56 | /* --- @gestr@ --- * |
| 57 | * |
| 58 | * Arguments: @group *g@ = a group |
| 59 | * @ge *x@ = a group element |
| 60 | * |
| 61 | * Returns: A pointer to the element's textual representation. |
| 62 | * |
| 63 | * Use: Converts a group element to a string. Corrupts |
| 64 | * @buf_t@. |
| 65 | */ |
| 66 | |
| 67 | const char *gestr(group *g, ge *x) |
| 68 | { |
| 69 | if (group_writestring(g, x, (char *)buf_t, sizeof(buf_t))) |
| 70 | return ("<failed>"); |
| 71 | return ((const char *)buf_t); |
| 72 | } |
| 73 | |
| 74 | /* --- @timestr@ --- * |
| 75 | * |
| 76 | * Arguments: @time_t t@ = a time to convert |
| 77 | * |
| 78 | * Returns: A pointer to a textual representation of the time. |
| 79 | * |
| 80 | * Use: Converts a time to a textual representation. Corrupts |
| 81 | * @buf_t@. |
| 82 | */ |
| 83 | |
| 84 | const char *timestr(time_t t) |
| 85 | { |
| 86 | struct tm *tm; |
| 87 | if (!t) |
| 88 | return ("NEVER"); |
| 89 | tm = localtime(&t); |
| 90 | strftime((char *)buf_t, sizeof(buf_t), "%Y-%m-%dT%H:%M:%S", tm); |
| 91 | return ((const char *)buf_t); |
| 92 | } |
| 93 | |
| 94 | /* --- @b64_encode@ --- * |
| 95 | * |
| 96 | * Arguments: @const void *p@ = pointer to some gorp |
| 97 | * @size_t sz@ = size of the gorp |
| 98 | * |
| 99 | * Returns: Pointer to base64-encoded version in @buf_t@. |
| 100 | */ |
| 101 | |
| 102 | const char *b64_encode(const void *p, size_t sz) |
| 103 | { |
| 104 | base64_ctx b64; |
| 105 | dstr d = DSTR_INIT; |
| 106 | |
| 107 | base64_init(&b64); |
| 108 | b64.indent = ""; |
| 109 | b64.maxline = 0; |
| 110 | base64_encode(&b64, p, sz, &d); |
| 111 | base64_encode(&b64, 0, 0, &d); |
| 112 | while (d.len && d.buf[d.len - 1] == '=') d.len--; |
| 113 | assert(d.len < sizeof(buf_t)); |
| 114 | memcpy(buf_t, d.buf, d.len); |
| 115 | buf_t[d.len] = 0; |
| 116 | dstr_destroy(&d); |
| 117 | return ((const char *)buf_t); |
| 118 | } |
| 119 | |
| 120 | /* --- @seq_reset@ --- * |
| 121 | * |
| 122 | * Arguments: @seqwin *s@ = sequence-checking window |
| 123 | * |
| 124 | * Returns: --- |
| 125 | * |
| 126 | * Use: Resets a sequence number window. |
| 127 | */ |
| 128 | |
| 129 | void seq_reset(seqwin *s) { s->seq = 0; s->win = 0; } |
| 130 | |
| 131 | /* --- @seq_check@ --- * |
| 132 | * |
| 133 | * Arguments: @seqwin *s@ = sequence-checking window |
| 134 | * @uint32 q@ = sequence number to check |
| 135 | * |
| 136 | * Returns: A @SEQ_@ code. |
| 137 | * |
| 138 | * Use: Checks a sequence number against the window, updating things |
| 139 | * as necessary. |
| 140 | */ |
| 141 | |
| 142 | int seq_check(seqwin *s, uint32 q) |
| 143 | { |
| 144 | uint32 qbit; |
| 145 | uint32 n; |
| 146 | |
| 147 | if (q < s->seq) |
| 148 | return (SEQ_OLD); |
| 149 | if (q >= s->seq + SEQ_WINSZ) { |
| 150 | n = q - (s->seq + SEQ_WINSZ - 1); |
| 151 | if (n < SEQ_WINSZ) |
| 152 | s->win >>= n; |
| 153 | else |
| 154 | s->win = 0; |
| 155 | s->seq += n; |
| 156 | } |
| 157 | qbit = 1 << (q - s->seq); |
| 158 | if (s->win & qbit) |
| 159 | return (SEQ_REPLAY); |
| 160 | s->win |= qbit; |
| 161 | return (0); |
| 162 | } |
| 163 | |
| 164 | /*----- That's all, folks -------------------------------------------------*/ |