1/*
2 * Copyright (c) 1995, 1996, 1997, 1998 Kungliga Tekniska Högskolan
3 * (Royal Institute of Technology, Stockholm, Sweden).
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 *
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 *
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * 3. Neither the name of the Institute nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#ifdef HAVE_CONFIG_H
35#include "config.h"
36RCSID("$Id$");
37#endif
38
39#include "otp_locl.h"
40
41#if !defined(HAVE_NDBM) && !defined(HAVE_DB_NDBM)
42#include "ndbm_wrap.h"
43#endif
44
45#define RETRIES 5
46
47void *
48otp_db_open (void)
49{
50  int lock;
51  int i;
52  void *ret;
53
54  for(i = 0; i < RETRIES; ++i) {
55    struct stat statbuf;
56
57    lock = open (OTP_DB_LOCK, O_WRONLY | O_CREAT | O_EXCL, 0666);
58    if (lock >= 0) {
59      close(lock);
60      break;
61    }
62    if (stat (OTP_DB_LOCK, &statbuf) == 0) {
63      if (time(NULL) - statbuf.st_mtime > OTP_DB_TIMEOUT)
64	unlink (OTP_DB_LOCK);
65      else
66	sleep (1);
67    }
68  }
69  if (i == RETRIES)
70    return NULL;
71  ret = dbm_open (OTP_DB, O_RDWR | O_CREAT, 0600);
72  if (ret == NULL)
73    unlink (OTP_DB_LOCK);
74  return ret;
75}
76
77void
78otp_db_close (void *dbm)
79{
80  dbm_close ((DBM *)dbm);
81  unlink (OTP_DB_LOCK);
82}
83
84/*
85 * Remove this entry from the database.
86 * return 0 if ok.
87 */
88
89int
90otp_delete (void *v, OtpContext *ctx)
91{
92  DBM *dbm = (DBM *)v;
93  datum key;
94
95  key.dsize = strlen(ctx->user);
96  key.dptr  = ctx->user;
97
98  return dbm_delete(dbm, key);
99}
100
101/*
102 * Read this entry from the database and lock it if lockp.
103 */
104
105static int
106otp_get_internal (void *v, OtpContext *ctx, int lockp)
107{
108  DBM *dbm = (DBM *)v;
109  datum dat, key;
110  char *p;
111  time_t now, then;
112
113  key.dsize = strlen(ctx->user);
114  key.dptr  = ctx->user;
115
116  dat = dbm_fetch (dbm, key);
117  if (dat.dptr == NULL) {
118    ctx->err = "Entry not found";
119    return -1;
120  }
121  p = dat.dptr;
122
123  memcpy (&then, p, sizeof(then));
124  ctx->lock_time = then;
125  if (lockp) {
126    time(&now);
127    if (then && now - then < OTP_USER_TIMEOUT) {
128      ctx->err = "Entry locked";
129      return -1;
130    }
131    memcpy (p, &now, sizeof(now));
132  }
133  p += sizeof(now);
134  ctx->alg = otp_find_alg (p);
135  if (ctx->alg == NULL) {
136    ctx->err = "Bad algorithm";
137    return -1;
138  }
139  p += strlen(p) + 1;
140  {
141    unsigned char *up = (unsigned char *)p;
142    ctx->n = (up[0] << 24) | (up[1] << 16) | (up[2] << 8) | up[3];
143  }
144  p += 4;
145  memcpy (ctx->key, p, OTPKEYSIZE);
146  p += OTPKEYSIZE;
147  strlcpy (ctx->seed, p, sizeof(ctx->seed));
148  if (lockp)
149    return dbm_store (dbm, key, dat, DBM_REPLACE);
150  else
151    return 0;
152}
153
154/*
155 * Get and lock.
156 */
157
158int
159otp_get (void *v, OtpContext *ctx)
160{
161  return otp_get_internal (v, ctx, 1);
162}
163
164/*
165 * Get and don't lock.
166 */
167
168int
169otp_simple_get (void *v, OtpContext *ctx)
170{
171  return otp_get_internal (v, ctx, 0);
172}
173
174/*
175 * Write this entry to the database.
176 */
177
178int
179otp_put (void *v, OtpContext *ctx)
180{
181  DBM *dbm = (DBM *)v;
182  datum dat, key;
183  char buf[1024], *p;
184  time_t zero = 0;
185  size_t len, rem;
186
187  key.dsize = strlen(ctx->user);
188  key.dptr  = ctx->user;
189
190  p = buf;
191  rem = sizeof(buf);
192
193  if (rem < sizeof(zero))
194      return -1;
195  memcpy (p, &zero, sizeof(zero));
196  p += sizeof(zero);
197  rem -= sizeof(zero);
198  len = strlen(ctx->alg->name) + 1;
199
200  if (rem < len)
201      return -1;
202  strlcpy (p, ctx->alg->name, rem);
203  p += len;
204  rem -= len;
205
206  if (rem < 4)
207      return -1;
208  {
209    unsigned char *up = (unsigned char *)p;
210    *up++ = (ctx->n >> 24) & 0xFF;
211    *up++ = (ctx->n >> 16) & 0xFF;
212    *up++ = (ctx->n >>  8) & 0xFF;
213    *up++ = (ctx->n >>  0) & 0xFF;
214  }
215  p += 4;
216  rem -= 4;
217
218  if (rem < OTPKEYSIZE)
219      return -1;
220  memcpy (p, ctx->key, OTPKEYSIZE);
221  p += OTPKEYSIZE;
222  rem -= OTPKEYSIZE;
223
224  len = strlen(ctx->seed) + 1;
225  if (rem < len)
226      return -1;
227  strlcpy (p, ctx->seed, rem);
228  p += len;
229  rem -= len;
230  dat.dptr  = buf;
231  dat.dsize = p - buf;
232  return dbm_store (dbm, key, dat, DBM_REPLACE);
233}
234