Commit | Line | Data |
---|---|---|
b2a56f7c SE |
1 | /* |
2 | * util.c | |
3 | * - output and logging support | |
4 | * - program lifetime support | |
5 | * - IP address and subnet munging routines | |
6 | * - MPI convenience functions | |
7 | */ | |
8 | /* | |
9 | * This file is | |
10 | * Copyright (C) 1995--2001 Stephen Early <steve@greenend.org.uk> | |
2fe58dfd | 11 | * |
b2a56f7c SE |
12 | * It is part of secnet, which is |
13 | * Copyright (C) 1995--2001 Stephen Early <steve@greenend.org.uk> | |
14 | * Copyright (C) 1998 Ross Anderson, Eli Biham, Lars Knudsen | |
15 | * | |
16 | * This program is free software; you can redistribute it and/or modify | |
17 | * it under the terms of the GNU General Public License as published by | |
18 | * the Free Software Foundation; either version 2, or (at your option) | |
19 | * any later version. | |
20 | * | |
21 | * This program is distributed in the hope that it will be useful, | |
22 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
23 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
24 | * GNU General Public License for more details. | |
25 | * | |
26 | * You should have received a copy of the GNU General Public License | |
27 | * along with this program; if not, write to the Free Software Foundation, | |
28 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. | |
2fe58dfd SE |
29 | */ |
30 | ||
8689b3a9 | 31 | #include "secnet.h" |
2fe58dfd | 32 | #include <stdio.h> |
2fe58dfd SE |
33 | #include <string.h> |
34 | #include <errno.h> | |
2fe58dfd | 35 | #include <unistd.h> |
59635212 | 36 | #include <limits.h> |
2fe58dfd | 37 | #include <assert.h> |
4efd681a | 38 | #include <sys/wait.h> |
2fe58dfd | 39 | #include "util.h" |
59635212 | 40 | #include "unaligned.h" |
8534d602 | 41 | #include "magic.h" |
2fe58dfd SE |
42 | |
43 | #define MIN_BUFFER_SIZE 64 | |
44 | #define DEFAULT_BUFFER_SIZE 4096 | |
45 | #define MAX_BUFFER_SIZE 131072 | |
46 | ||
fe5e9cc4 | 47 | static const char *hexdigits="0123456789abcdef"; |
2fe58dfd | 48 | |
7138d0c5 | 49 | uint32_t current_phase=0; |
2fe58dfd SE |
50 | |
51 | struct phase_hook { | |
52 | hook_fn *fn; | |
53 | void *state; | |
54 | struct phase_hook *next; | |
55 | }; | |
56 | ||
57 | static struct phase_hook *hooks[NR_PHASES]={NULL,}; | |
58 | ||
fe5e9cc4 | 59 | char *safe_strdup(const char *s, const char *message) |
2fe58dfd SE |
60 | { |
61 | char *d; | |
62 | d=strdup(s); | |
63 | if (!d) { | |
779837e1 | 64 | fatal_perror("%s",message); |
2fe58dfd SE |
65 | } |
66 | return d; | |
67 | } | |
68 | ||
fe5e9cc4 | 69 | void *safe_malloc(size_t size, const char *message) |
2fe58dfd SE |
70 | { |
71 | void *r; | |
72 | r=malloc(size); | |
73 | if (!r) { | |
779837e1 | 74 | fatal_perror("%s",message); |
2fe58dfd SE |
75 | } |
76 | return r; | |
77 | } | |
bb9d0561 IJ |
78 | void *safe_malloc_ary(size_t size, size_t count, const char *message) { |
79 | if (count >= INT_MAX/size) { | |
80 | fatal("array allocation overflow: %s", message); | |
81 | } | |
82 | return safe_malloc(size*count, message); | |
83 | } | |
2fe58dfd SE |
84 | |
85 | /* Convert a buffer into its MP_INT representation */ | |
86 | void read_mpbin(MP_INT *a, uint8_t *bin, int binsize) | |
87 | { | |
88 | char *buff; | |
89 | int i; | |
90 | ||
91 | buff=safe_malloc(binsize*2 + 1,"read_mpbin"); | |
92 | ||
93 | for (i=0; i<binsize; i++) { | |
94 | buff[i*2]=hexdigits[(bin[i] & 0xf0) >> 4]; | |
95 | buff[i*2+1]=hexdigits[(bin[i] & 0xf)]; | |
96 | } | |
97 | buff[binsize*2]=0; | |
98 | ||
99 | mpz_set_str(a, buff, 16); | |
100 | free(buff); | |
101 | } | |
102 | ||
103 | /* Convert a MP_INT into a hex string */ | |
104 | char *write_mpstring(MP_INT *a) | |
105 | { | |
106 | char *buff; | |
107 | ||
108 | buff=safe_malloc(mpz_sizeinbase(a,16)+2,"write_mpstring"); | |
109 | mpz_get_str(buff, 16, a); | |
110 | return buff; | |
111 | } | |
112 | ||
113 | static uint8_t hexval(uint8_t c) | |
114 | { | |
115 | switch (c) { | |
116 | case '0': return 0; | |
117 | case '1': return 1; | |
118 | case '2': return 2; | |
119 | case '3': return 3; | |
120 | case '4': return 4; | |
121 | case '5': return 5; | |
122 | case '6': return 6; | |
123 | case '7': return 7; | |
124 | case '8': return 8; | |
125 | case '9': return 9; | |
126 | case 'a': return 10; | |
127 | case 'A': return 10; | |
128 | case 'b': return 11; | |
129 | case 'B': return 11; | |
130 | case 'c': return 12; | |
131 | case 'C': return 12; | |
132 | case 'd': return 13; | |
133 | case 'D': return 13; | |
134 | case 'e': return 14; | |
135 | case 'E': return 14; | |
136 | case 'f': return 15; | |
137 | case 'F': return 15; | |
138 | } | |
139 | return -1; | |
140 | } | |
141 | ||
142 | /* Convert a MP_INT into a buffer; return length; truncate if necessary */ | |
1caa23ff | 143 | int32_t write_mpbin(MP_INT *a, uint8_t *buffer, int32_t buflen) |
2fe58dfd SE |
144 | { |
145 | char *hb; | |
146 | int i,j,l; | |
147 | ||
148 | if (buflen==0) return 0; | |
149 | hb=write_mpstring(a); | |
150 | ||
151 | l=strlen(hb); | |
152 | i=0; j=0; | |
153 | if (l&1) { | |
154 | /* The number starts with a half-byte */ | |
155 | buffer[i++]=hexval(hb[j++]); | |
156 | } | |
157 | for (; hb[j] && i<buflen; i++) { | |
158 | buffer[i]=(hexval(hb[j])<<4)|hexval(hb[j+1]); | |
159 | j+=2; | |
160 | } | |
161 | free(hb); | |
162 | return i; | |
163 | } | |
164 | ||
4fb0f88d IJ |
165 | void setcloexec(int fd) { |
166 | int r=fcntl(fd, F_GETFD); | |
167 | if (r<0) fatal_perror("fcntl(,F_GETFD) failed"); | |
168 | r=fcntl(fd, F_SETFD, r|FD_CLOEXEC); | |
169 | if (r<0) fatal_perror("fcntl(,F_SETFD,|FD_CLOEXEC) failed"); | |
170 | } | |
171 | ||
6a06198c IJ |
172 | void pipe_cloexec(int fd[2]) { |
173 | int r=pipe(fd); | |
174 | if (r) fatal_perror("pipe"); | |
175 | setcloexec(fd[0]); | |
176 | setcloexec(fd[1]); | |
177 | } | |
178 | ||
fe5e9cc4 | 179 | static const char *phases[NR_PHASES]={ |
2fe58dfd SE |
180 | "PHASE_INIT", |
181 | "PHASE_GETOPTS", | |
182 | "PHASE_READCONFIG", | |
183 | "PHASE_SETUP", | |
7b1a9fb7 | 184 | "PHASE_DAEMONIZE", |
baa06aeb | 185 | "PHASE_GETRESOURCES", |
2fe58dfd SE |
186 | "PHASE_DROPPRIV", |
187 | "PHASE_RUN", | |
188 | "PHASE_SHUTDOWN" | |
189 | }; | |
190 | ||
191 | void enter_phase(uint32_t new_phase) | |
192 | { | |
193 | struct phase_hook *i; | |
194 | ||
baa06aeb SE |
195 | if (hooks[new_phase]) |
196 | Message(M_DEBUG_PHASE,"Running hooks for %s...\n", phases[new_phase]); | |
2fe58dfd SE |
197 | current_phase=new_phase; |
198 | ||
199 | for (i=hooks[new_phase]; i; i=i->next) | |
200 | i->fn(i->state, new_phase); | |
baa06aeb | 201 | Message(M_DEBUG_PHASE,"Now in %s\n",phases[new_phase]); |
2fe58dfd SE |
202 | } |
203 | ||
204 | bool_t add_hook(uint32_t phase, hook_fn *fn, void *state) | |
205 | { | |
206 | struct phase_hook *h; | |
207 | ||
208 | h=safe_malloc(sizeof(*h),"add_hook"); | |
209 | h->fn=fn; | |
210 | h->state=state; | |
211 | h->next=hooks[phase]; | |
212 | hooks[phase]=h; | |
213 | return True; | |
214 | } | |
215 | ||
216 | bool_t remove_hook(uint32_t phase, hook_fn *fn, void *state) | |
217 | { | |
4f5e39ec | 218 | fatal("remove_hook: not implemented"); |
2fe58dfd SE |
219 | |
220 | return False; | |
221 | } | |
222 | ||
59938e0e IJ |
223 | void vslilog(struct log_if *lf, int priority, const char *message, va_list ap) |
224 | { | |
779837e1 | 225 | lf->vlogfn(lf->st,priority,message,ap); |
59938e0e IJ |
226 | } |
227 | ||
040ee979 | 228 | void slilog(struct log_if *lf, int priority, const char *message, ...) |
2fe58dfd SE |
229 | { |
230 | va_list ap; | |
231 | ||
232 | va_start(ap,message); | |
59938e0e | 233 | vslilog(lf,priority,message,ap); |
2fe58dfd SE |
234 | va_end(ap); |
235 | } | |
236 | ||
237 | struct buffer { | |
238 | closure_t cl; | |
239 | struct buffer_if ops; | |
240 | }; | |
241 | ||
fe5e9cc4 | 242 | void buffer_assert_free(struct buffer_if *buffer, cstring_t file, |
1caa23ff | 243 | int line) |
2fe58dfd SE |
244 | { |
245 | if (!buffer->free) { | |
28db900b IJ |
246 | fprintf(stderr,"secnet: BUF_ASSERT_FREE, %s line %d, owned by %s", |
247 | file,line,buffer->owner); | |
248 | assert(!"buffer_assert_free failure"); | |
2fe58dfd SE |
249 | } |
250 | } | |
251 | ||
fe5e9cc4 | 252 | void buffer_assert_used(struct buffer_if *buffer, cstring_t file, |
1caa23ff | 253 | int line) |
2fe58dfd SE |
254 | { |
255 | if (buffer->free) { | |
28db900b IJ |
256 | fprintf(stderr,"secnet: BUF_ASSERT_USED, %s line %d, last owned by %s", |
257 | file,line,buffer->owner); | |
258 | assert(!"buffer_assert_used failure"); | |
2fe58dfd SE |
259 | } |
260 | } | |
261 | ||
1caa23ff | 262 | void buffer_init(struct buffer_if *buffer, int32_t max_start_pad) |
2fe58dfd | 263 | { |
10068344 | 264 | assert(max_start_pad<=buffer->alloclen); |
2fe58dfd SE |
265 | buffer->start=buffer->base+max_start_pad; |
266 | buffer->size=0; | |
267 | } | |
268 | ||
1caa23ff | 269 | void *buf_append(struct buffer_if *buf, int32_t amount) { |
2fe58dfd | 270 | void *p; |
92795040 | 271 | assert(amount <= buf_remaining_space(buf)); |
2fe58dfd SE |
272 | p=buf->start + buf->size; |
273 | buf->size+=amount; | |
274 | return p; | |
275 | } | |
276 | ||
1caa23ff | 277 | void *buf_prepend(struct buffer_if *buf, int32_t amount) { |
59230b9b | 278 | assert(amount <= buf->start - buf->base); |
2fe58dfd SE |
279 | buf->size+=amount; |
280 | return buf->start-=amount; | |
281 | } | |
282 | ||
1caa23ff | 283 | void *buf_unappend(struct buffer_if *buf, int32_t amount) { |
2fe58dfd SE |
284 | if (buf->size < amount) return 0; |
285 | return buf->start+(buf->size-=amount); | |
286 | } | |
287 | ||
1caa23ff | 288 | void *buf_unprepend(struct buffer_if *buf, int32_t amount) { |
2fe58dfd | 289 | void *p; |
20138876 | 290 | if (buf->size < amount) return 0; |
2fe58dfd SE |
291 | p=buf->start; |
292 | buf->start+=amount; | |
293 | buf->size-=amount; | |
294 | return p; | |
295 | } | |
296 | ||
297 | /* Append a two-byte length and the string to the buffer. Length is in | |
298 | network byte order. */ | |
fe5e9cc4 | 299 | void buf_append_string(struct buffer_if *buf, cstring_t s) |
2fe58dfd | 300 | { |
1caa23ff | 301 | size_t len; |
2fe58dfd SE |
302 | |
303 | len=strlen(s); | |
59230b9b | 304 | /* fixme: if string is longer than 65535, result is a corrupted packet */ |
59635212 | 305 | buf_append_uint16(buf,len); |
4f28e77e | 306 | BUF_ADD_BYTES(append,buf,s,len); |
2fe58dfd SE |
307 | } |
308 | ||
1caa23ff | 309 | void buffer_new(struct buffer_if *buf, int32_t len) |
2fe58dfd SE |
310 | { |
311 | buf->free=True; | |
312 | buf->owner=NULL; | |
313 | buf->flags=0; | |
314 | buf->loc.file=NULL; | |
315 | buf->loc.line=0; | |
316 | buf->size=0; | |
10068344 | 317 | buf->alloclen=len; |
2fe58dfd SE |
318 | buf->start=NULL; |
319 | buf->base=safe_malloc(len,"buffer_new"); | |
320 | } | |
321 | ||
28db900b IJ |
322 | void buffer_readonly_view(struct buffer_if *buf, const void *data, int32_t len) |
323 | { | |
324 | buf->free=False; | |
325 | buf->owner="READONLY"; | |
326 | buf->flags=0; | |
327 | buf->loc.file=NULL; | |
328 | buf->loc.line=0; | |
10068344 | 329 | buf->size=buf->alloclen=len; |
28db900b IJ |
330 | buf->base=buf->start=(uint8_t*)data; |
331 | } | |
332 | ||
333 | void buffer_readonly_clone(struct buffer_if *out, const struct buffer_if *in) | |
334 | { | |
335 | buffer_readonly_view(out,in->start,in->size); | |
336 | } | |
337 | ||
05f39b4d IJ |
338 | void buffer_copy(struct buffer_if *dst, const struct buffer_if *src) |
339 | { | |
10068344 IJ |
340 | if (dst->alloclen < src->alloclen) { |
341 | dst->base=realloc(dst->base,src->alloclen); | |
05f39b4d | 342 | if (!dst->base) fatal_perror("buffer_copy"); |
10068344 | 343 | dst->alloclen = src->alloclen; |
05f39b4d IJ |
344 | } |
345 | dst->start = dst->base + (src->start - src->base); | |
346 | dst->size = src->size; | |
347 | memcpy(dst->start, src->start, dst->size); | |
348 | } | |
349 | ||
2fe58dfd SE |
350 | static list_t *buffer_apply(closure_t *self, struct cloc loc, dict_t *context, |
351 | list_t *args) | |
352 | { | |
353 | struct buffer *st; | |
354 | item_t *item; | |
355 | dict_t *dict; | |
356 | bool_t lockdown=False; | |
4efd681a | 357 | uint32_t len=DEFAULT_BUFFER_SIZE; |
2fe58dfd SE |
358 | |
359 | st=safe_malloc(sizeof(*st),"buffer_apply"); | |
360 | st->cl.description="buffer"; | |
361 | st->cl.type=CL_BUFFER; | |
362 | st->cl.apply=NULL; | |
363 | st->cl.interface=&st->ops; | |
2fe58dfd SE |
364 | |
365 | /* First argument, if present, is buffer length */ | |
366 | item=list_elem(args,0); | |
367 | if (item) { | |
368 | if (item->type!=t_number) { | |
369 | cfgfatal(st->ops.loc,"buffer","first parameter must be a " | |
370 | "number (buffer size)\n"); | |
371 | } | |
4efd681a SE |
372 | len=item->data.number; |
373 | if (len<MIN_BUFFER_SIZE) { | |
2fe58dfd SE |
374 | cfgfatal(st->ops.loc,"buffer","ludicrously small buffer size\n"); |
375 | } | |
4efd681a | 376 | if (len>MAX_BUFFER_SIZE) { |
2fe58dfd SE |
377 | cfgfatal(st->ops.loc,"buffer","ludicrously large buffer size\n"); |
378 | } | |
379 | } | |
380 | /* Second argument, if present, is a dictionary */ | |
381 | item=list_elem(args,1); | |
382 | if (item) { | |
383 | if (item->type!=t_dict) { | |
384 | cfgfatal(st->ops.loc,"buffer","second parameter must be a " | |
385 | "dictionary\n"); | |
386 | } | |
387 | dict=item->data.dict; | |
388 | lockdown=dict_read_bool(dict,"lockdown",False,"buffer",st->ops.loc, | |
389 | False); | |
390 | } | |
391 | ||
4efd681a | 392 | buffer_new(&st->ops,len); |
2fe58dfd | 393 | if (lockdown) { |
70dc107b | 394 | /* XXX mlock the buffer if possible */ |
2fe58dfd SE |
395 | } |
396 | ||
397 | return new_closure(&st->cl); | |
398 | } | |
399 | ||
8534d602 IJ |
400 | void send_nak(const struct comm_addr *dest, uint32_t our_index, |
401 | uint32_t their_index, uint32_t msgtype, | |
402 | struct buffer_if *buf, const char *logwhy) | |
403 | { | |
3abd18e8 | 404 | buffer_init(buf,calculate_max_start_pad()); |
8534d602 IJ |
405 | buf_append_uint32(buf,their_index); |
406 | buf_append_uint32(buf,our_index); | |
407 | buf_append_uint32(buf,LABEL_NAK); | |
408 | if (logwhy) | |
409 | Message(M_INFO,"%s: %08"PRIx32"<-%08"PRIx32": %08"PRIx32":" | |
410 | " %s; sending NAK\n", | |
1a448682 | 411 | comm_addr_to_string(dest), |
8534d602 IJ |
412 | our_index, their_index, msgtype, logwhy); |
413 | dest->comm->sendmsg(dest->comm->st, buf, dest); | |
414 | } | |
415 | ||
5ad34db2 IJ |
416 | int consttime_memeq(const void *s1in, const void *s2in, size_t n) |
417 | { | |
418 | const uint8_t *s1=s1in, *s2=s2in; | |
419 | register volatile uint8_t accumulator=0; | |
420 | ||
421 | while (n-- > 0) { | |
422 | accumulator |= (*s1++ ^ *s2++); | |
423 | } | |
424 | accumulator |= accumulator >> 4; /* constant-time */ | |
425 | accumulator |= accumulator >> 2; /* boolean canonicalisation */ | |
426 | accumulator |= accumulator >> 1; | |
427 | accumulator &= 1; | |
428 | accumulator ^= 1; | |
429 | return accumulator; | |
430 | } | |
431 | ||
2fe58dfd SE |
432 | void util_module(dict_t *dict) |
433 | { | |
2fe58dfd SE |
434 | add_closure(dict,"sysbuffer",buffer_apply); |
435 | } | |
3abd18e8 IJ |
436 | |
437 | void update_max_start_pad(int32_t *our_module_global, int32_t our_instance) | |
438 | { | |
439 | if (*our_module_global < our_instance) | |
440 | *our_module_global=our_instance; | |
441 | } | |
442 | ||
443 | int32_t transform_max_start_pad, comm_max_start_pad; | |
444 | ||
445 | int32_t calculate_max_start_pad(void) | |
446 | { | |
447 | return | |
448 | site_max_start_pad + | |
449 | transform_max_start_pad + | |
450 | comm_max_start_pad; | |
451 | } | |
ff1dcd86 IJ |
452 | |
453 | void vslilog_part(struct log_if *lf, int priority, const char *message, va_list ap) | |
454 | { | |
455 | char *buff=lf->buff; | |
456 | size_t bp; | |
457 | char *nlp; | |
458 | ||
459 | bp=strlen(buff); | |
460 | assert(bp < LOG_MESSAGE_BUFLEN); | |
461 | vsnprintf(buff+bp,LOG_MESSAGE_BUFLEN-bp,message,ap); | |
462 | buff[LOG_MESSAGE_BUFLEN-1] = '\n'; | |
463 | buff[LOG_MESSAGE_BUFLEN] = '\0'; | |
464 | /* Each line is sent separately */ | |
465 | while ((nlp=strchr(buff,'\n'))) { | |
466 | *nlp=0; | |
467 | slilog(lf,priority,"%s",buff); | |
468 | memmove(buff,nlp+1,strlen(nlp+1)+1); | |
469 | } | |
470 | } | |
471 | ||
472 | extern void slilog_part(struct log_if *lf, int priority, const char *message, ...) | |
473 | { | |
474 | va_list ap; | |
475 | va_start(ap,message); | |
476 | vslilog_part(lf,priority,message,ap); | |
477 | va_end(ap); | |
478 | } |