Contents of /trunk/mkinitrd-magellan/busybox/e2fsprogs/old_e2fsprogs/uuid/gen_uuid.c
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Revision 984 -
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Sun May 30 11:32:42 2010 UTC (13 years, 11 months ago) by niro
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Sun May 30 11:32:42 2010 UTC (13 years, 11 months ago) by niro
File MIME type: text/plain
File size: 7749 byte(s)
-updated to busybox-1.16.1 and enabled blkid/uuid support in default config
1 | /* vi: set sw=4 ts=4: */ |
2 | /* |
3 | * gen_uuid.c --- generate a DCE-compatible uuid |
4 | * |
5 | * Copyright (C) 1996, 1997, 1998, 1999 Theodore Ts'o. |
6 | * |
7 | * %Begin-Header% |
8 | * Redistribution and use in source and binary forms, with or without |
9 | * modification, are permitted provided that the following conditions |
10 | * are met: |
11 | * 1. Redistributions of source code must retain the above copyright |
12 | * notice, and the entire permission notice in its entirety, |
13 | * including the disclaimer of warranties. |
14 | * 2. Redistributions in binary form must reproduce the above copyright |
15 | * notice, this list of conditions and the following disclaimer in the |
16 | * documentation and/or other materials provided with the distribution. |
17 | * 3. The name of the author may not be used to endorse or promote |
18 | * products derived from this software without specific prior |
19 | * written permission. |
20 | * |
21 | * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED |
22 | * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
23 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ALL OF |
24 | * WHICH ARE HEREBY DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE |
25 | * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
26 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT |
27 | * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR |
28 | * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF |
29 | * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
30 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE |
31 | * USE OF THIS SOFTWARE, EVEN IF NOT ADVISED OF THE POSSIBILITY OF SUCH |
32 | * DAMAGE. |
33 | * %End-Header% |
34 | */ |
35 | |
36 | #include <unistd.h> |
37 | #include <stdlib.h> |
38 | #include <string.h> |
39 | #include <fcntl.h> |
40 | #include <errno.h> |
41 | #include <sys/types.h> |
42 | #include <sys/stat.h> |
43 | #include <sys/file.h> |
44 | #include <sys/time.h> |
45 | #ifdef HAVE_SYS_IOCTL_H |
46 | #include <sys/ioctl.h> |
47 | #endif |
48 | #include <sys/socket.h> |
49 | #ifdef HAVE_SYS_SOCKIO_H |
50 | #include <sys/sockio.h> |
51 | #endif |
52 | #ifdef HAVE_NET_IF_H |
53 | #include <net/if.h> |
54 | #endif |
55 | #ifdef HAVE_NETINET_IN_H |
56 | #include <netinet/in.h> |
57 | #endif |
58 | #ifdef HAVE_NET_IF_DL_H |
59 | #include <net/if_dl.h> |
60 | #endif |
61 | |
62 | #include "uuidP.h" |
63 | |
64 | #ifdef HAVE_SRANDOM |
65 | #define srand(x) srandom(x) |
66 | #define rand() random() |
67 | #endif |
68 | |
69 | static int get_random_fd(void) |
70 | { |
71 | struct timeval tv; |
72 | static int fd = -2; |
73 | int i; |
74 | |
75 | if (fd == -2) { |
76 | gettimeofday(&tv, 0); |
77 | fd = open("/dev/urandom", O_RDONLY); |
78 | if (fd == -1) |
79 | fd = open("/dev/random", O_RDONLY | O_NONBLOCK); |
80 | srand((getpid() << 16) ^ getuid() ^ tv.tv_sec ^ tv.tv_usec); |
81 | } |
82 | /* Crank the random number generator a few times */ |
83 | gettimeofday(&tv, 0); |
84 | for (i = (tv.tv_sec ^ tv.tv_usec) & 0x1F; i > 0; i--) |
85 | rand(); |
86 | return fd; |
87 | } |
88 | |
89 | |
90 | /* |
91 | * Generate a series of random bytes. Use /dev/urandom if possible, |
92 | * and if not, use srandom/random. |
93 | */ |
94 | static void get_random_bytes(void *buf, int nbytes) |
95 | { |
96 | int i, n = nbytes, fd = get_random_fd(); |
97 | int lose_counter = 0; |
98 | unsigned char *cp = (unsigned char *) buf; |
99 | |
100 | if (fd >= 0) { |
101 | while (n > 0) { |
102 | i = read(fd, cp, n); |
103 | if (i <= 0) { |
104 | if (lose_counter++ > 16) |
105 | break; |
106 | continue; |
107 | } |
108 | n -= i; |
109 | cp += i; |
110 | lose_counter = 0; |
111 | } |
112 | } |
113 | |
114 | /* |
115 | * We do this all the time, but this is the only source of |
116 | * randomness if /dev/random/urandom is out to lunch. |
117 | */ |
118 | for (cp = buf, i = 0; i < nbytes; i++) |
119 | *cp++ ^= (rand() >> 7) & 0xFF; |
120 | } |
121 | |
122 | /* |
123 | * Get the ethernet hardware address, if we can find it... |
124 | */ |
125 | static int get_node_id(unsigned char *node_id) |
126 | { |
127 | #ifdef HAVE_NET_IF_H |
128 | int sd; |
129 | struct ifreq ifr, *ifrp; |
130 | struct ifconf ifc; |
131 | char buf[1024]; |
132 | int n, i; |
133 | unsigned char *a; |
134 | #ifdef HAVE_NET_IF_DL_H |
135 | struct sockaddr_dl *sdlp; |
136 | #endif |
137 | |
138 | /* |
139 | * BSD 4.4 defines the size of an ifreq to be |
140 | * max(sizeof(ifreq), sizeof(ifreq.ifr_name)+ifreq.ifr_addr.sa_len |
141 | * However, under earlier systems, sa_len isn't present, so the size is |
142 | * just sizeof(struct ifreq) |
143 | */ |
144 | #ifdef HAVE_SA_LEN |
145 | #ifndef max |
146 | #define max(a,b) ((a) > (b) ? (a) : (b)) |
147 | #endif |
148 | #define ifreq_size(i) max(sizeof(struct ifreq),\ |
149 | sizeof((i).ifr_name)+(i).ifr_addr.sa_len) |
150 | #else |
151 | #define ifreq_size(i) sizeof(struct ifreq) |
152 | #endif /* HAVE_SA_LEN*/ |
153 | |
154 | sd = socket(AF_INET, SOCK_DGRAM, IPPROTO_IP); |
155 | if (sd < 0) { |
156 | return -1; |
157 | } |
158 | memset(buf, 0, sizeof(buf)); |
159 | ifc.ifc_len = sizeof(buf); |
160 | ifc.ifc_buf = buf; |
161 | if (ioctl (sd, SIOCGIFCONF, (char *)&ifc) < 0) { |
162 | close(sd); |
163 | return -1; |
164 | } |
165 | n = ifc.ifc_len; |
166 | for (i = 0; i < n; i+= ifreq_size(*ifrp) ) { |
167 | ifrp = (struct ifreq *)((char *) ifc.ifc_buf+i); |
168 | strncpy_IFNAMSIZ(ifr.ifr_name, ifrp->ifr_name); |
169 | #ifdef SIOCGIFHWADDR |
170 | if (ioctl(sd, SIOCGIFHWADDR, &ifr) < 0) |
171 | continue; |
172 | a = (unsigned char *) &ifr.ifr_hwaddr.sa_data; |
173 | #else |
174 | #ifdef SIOCGENADDR |
175 | if (ioctl(sd, SIOCGENADDR, &ifr) < 0) |
176 | continue; |
177 | a = (unsigned char *) ifr.ifr_enaddr; |
178 | #else |
179 | #ifdef HAVE_NET_IF_DL_H |
180 | sdlp = (struct sockaddr_dl *) &ifrp->ifr_addr; |
181 | if ((sdlp->sdl_family != AF_LINK) || (sdlp->sdl_alen != 6)) |
182 | continue; |
183 | a = (unsigned char *) &sdlp->sdl_data[sdlp->sdl_nlen]; |
184 | #else |
185 | /* |
186 | * XXX we don't have a way of getting the hardware |
187 | * address |
188 | */ |
189 | close(sd); |
190 | return 0; |
191 | #endif /* HAVE_NET_IF_DL_H */ |
192 | #endif /* SIOCGENADDR */ |
193 | #endif /* SIOCGIFHWADDR */ |
194 | if (!a[0] && !a[1] && !a[2] && !a[3] && !a[4] && !a[5]) |
195 | continue; |
196 | if (node_id) { |
197 | memcpy(node_id, a, 6); |
198 | close(sd); |
199 | return 1; |
200 | } |
201 | } |
202 | close(sd); |
203 | #endif |
204 | return 0; |
205 | } |
206 | |
207 | /* Assume that the gettimeofday() has microsecond granularity */ |
208 | #define MAX_ADJUSTMENT 10 |
209 | |
210 | static int get_clock(uint32_t *clock_high, uint32_t *clock_low, uint16_t *ret_clock_seq) |
211 | { |
212 | static int adjustment = 0; |
213 | static struct timeval last = {0, 0}; |
214 | static uint16_t clock_seq; |
215 | struct timeval tv; |
216 | unsigned long long clock_reg; |
217 | |
218 | try_again: |
219 | gettimeofday(&tv, 0); |
220 | if ((last.tv_sec == 0) && (last.tv_usec == 0)) { |
221 | get_random_bytes(&clock_seq, sizeof(clock_seq)); |
222 | clock_seq &= 0x3FFF; |
223 | last = tv; |
224 | last.tv_sec--; |
225 | } |
226 | if ((tv.tv_sec < last.tv_sec) || |
227 | ((tv.tv_sec == last.tv_sec) && |
228 | (tv.tv_usec < last.tv_usec))) { |
229 | clock_seq = (clock_seq+1) & 0x3FFF; |
230 | adjustment = 0; |
231 | last = tv; |
232 | } else if ((tv.tv_sec == last.tv_sec) && |
233 | (tv.tv_usec == last.tv_usec)) { |
234 | if (adjustment >= MAX_ADJUSTMENT) |
235 | goto try_again; |
236 | adjustment++; |
237 | } else { |
238 | adjustment = 0; |
239 | last = tv; |
240 | } |
241 | |
242 | clock_reg = tv.tv_usec*10 + adjustment; |
243 | clock_reg += ((unsigned long long) tv.tv_sec)*10000000; |
244 | clock_reg += (((unsigned long long) 0x01B21DD2) << 32) + 0x13814000; |
245 | |
246 | *clock_high = clock_reg >> 32; |
247 | *clock_low = clock_reg; |
248 | *ret_clock_seq = clock_seq; |
249 | return 0; |
250 | } |
251 | |
252 | void uuid_generate_time(uuid_t out) |
253 | { |
254 | static unsigned char node_id[6]; |
255 | static int has_init = 0; |
256 | struct uuid uu; |
257 | uint32_t clock_mid; |
258 | |
259 | if (!has_init) { |
260 | if (get_node_id(node_id) <= 0) { |
261 | get_random_bytes(node_id, 6); |
262 | /* |
263 | * Set multicast bit, to prevent conflicts |
264 | * with IEEE 802 addresses obtained from |
265 | * network cards |
266 | */ |
267 | node_id[0] |= 0x01; |
268 | } |
269 | has_init = 1; |
270 | } |
271 | get_clock(&clock_mid, &uu.time_low, &uu.clock_seq); |
272 | uu.clock_seq |= 0x8000; |
273 | uu.time_mid = (uint16_t) clock_mid; |
274 | uu.time_hi_and_version = ((clock_mid >> 16) & 0x0FFF) | 0x1000; |
275 | memcpy(uu.node, node_id, 6); |
276 | uuid_pack(&uu, out); |
277 | } |
278 | |
279 | void uuid_generate_random(uuid_t out) |
280 | { |
281 | uuid_t buf; |
282 | struct uuid uu; |
283 | |
284 | get_random_bytes(buf, sizeof(buf)); |
285 | uuid_unpack(buf, &uu); |
286 | |
287 | uu.clock_seq = (uu.clock_seq & 0x3FFF) | 0x8000; |
288 | uu.time_hi_and_version = (uu.time_hi_and_version & 0x0FFF) | 0x4000; |
289 | uuid_pack(&uu, out); |
290 | } |
291 | |
292 | /* |
293 | * This is the generic front-end to uuid_generate_random and |
294 | * uuid_generate_time. It uses uuid_generate_random only if |
295 | * /dev/urandom is available, since otherwise we won't have |
296 | * high-quality randomness. |
297 | */ |
298 | void uuid_generate(uuid_t out) |
299 | { |
300 | if (get_random_fd() >= 0) |
301 | uuid_generate_random(out); |
302 | else |
303 | uuid_generate_time(out); |
304 | } |