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 | ||
fe5e9cc4 | 165 | static const char *phases[NR_PHASES]={ |
2fe58dfd SE |
166 | "PHASE_INIT", |
167 | "PHASE_GETOPTS", | |
168 | "PHASE_READCONFIG", | |
169 | "PHASE_SETUP", | |
7b1a9fb7 | 170 | "PHASE_DAEMONIZE", |
baa06aeb | 171 | "PHASE_GETRESOURCES", |
2fe58dfd SE |
172 | "PHASE_DROPPRIV", |
173 | "PHASE_RUN", | |
174 | "PHASE_SHUTDOWN" | |
175 | }; | |
176 | ||
177 | void enter_phase(uint32_t new_phase) | |
178 | { | |
179 | struct phase_hook *i; | |
180 | ||
baa06aeb SE |
181 | if (hooks[new_phase]) |
182 | Message(M_DEBUG_PHASE,"Running hooks for %s...\n", phases[new_phase]); | |
2fe58dfd SE |
183 | current_phase=new_phase; |
184 | ||
185 | for (i=hooks[new_phase]; i; i=i->next) | |
186 | i->fn(i->state, new_phase); | |
baa06aeb | 187 | Message(M_DEBUG_PHASE,"Now in %s\n",phases[new_phase]); |
2fe58dfd SE |
188 | } |
189 | ||
190 | bool_t add_hook(uint32_t phase, hook_fn *fn, void *state) | |
191 | { | |
192 | struct phase_hook *h; | |
193 | ||
194 | h=safe_malloc(sizeof(*h),"add_hook"); | |
195 | h->fn=fn; | |
196 | h->state=state; | |
197 | h->next=hooks[phase]; | |
198 | hooks[phase]=h; | |
199 | return True; | |
200 | } | |
201 | ||
202 | bool_t remove_hook(uint32_t phase, hook_fn *fn, void *state) | |
203 | { | |
4f5e39ec | 204 | fatal("remove_hook: not implemented"); |
2fe58dfd SE |
205 | |
206 | return False; | |
207 | } | |
208 | ||
59938e0e IJ |
209 | void vslilog(struct log_if *lf, int priority, const char *message, va_list ap) |
210 | { | |
779837e1 | 211 | lf->vlogfn(lf->st,priority,message,ap); |
59938e0e IJ |
212 | } |
213 | ||
040ee979 | 214 | void slilog(struct log_if *lf, int priority, const char *message, ...) |
2fe58dfd SE |
215 | { |
216 | va_list ap; | |
217 | ||
218 | va_start(ap,message); | |
59938e0e | 219 | vslilog(lf,priority,message,ap); |
2fe58dfd SE |
220 | va_end(ap); |
221 | } | |
222 | ||
223 | struct buffer { | |
224 | closure_t cl; | |
225 | struct buffer_if ops; | |
226 | }; | |
227 | ||
fe5e9cc4 | 228 | void buffer_assert_free(struct buffer_if *buffer, cstring_t file, |
1caa23ff | 229 | int line) |
2fe58dfd SE |
230 | { |
231 | if (!buffer->free) { | |
28db900b IJ |
232 | fprintf(stderr,"secnet: BUF_ASSERT_FREE, %s line %d, owned by %s", |
233 | file,line,buffer->owner); | |
234 | assert(!"buffer_assert_free failure"); | |
2fe58dfd SE |
235 | } |
236 | } | |
237 | ||
fe5e9cc4 | 238 | void buffer_assert_used(struct buffer_if *buffer, cstring_t file, |
1caa23ff | 239 | int line) |
2fe58dfd SE |
240 | { |
241 | if (buffer->free) { | |
28db900b IJ |
242 | fprintf(stderr,"secnet: BUF_ASSERT_USED, %s line %d, last owned by %s", |
243 | file,line,buffer->owner); | |
244 | assert(!"buffer_assert_used failure"); | |
2fe58dfd SE |
245 | } |
246 | } | |
247 | ||
1caa23ff | 248 | void buffer_init(struct buffer_if *buffer, int32_t max_start_pad) |
2fe58dfd | 249 | { |
1ce2f8bc | 250 | assert(max_start_pad<=buffer->len); |
2fe58dfd SE |
251 | buffer->start=buffer->base+max_start_pad; |
252 | buffer->size=0; | |
253 | } | |
254 | ||
1caa23ff | 255 | void *buf_append(struct buffer_if *buf, int32_t amount) { |
2fe58dfd | 256 | void *p; |
59230b9b | 257 | assert(buf->size <= buf->len - amount); |
2fe58dfd SE |
258 | p=buf->start + buf->size; |
259 | buf->size+=amount; | |
260 | return p; | |
261 | } | |
262 | ||
1caa23ff | 263 | void *buf_prepend(struct buffer_if *buf, int32_t amount) { |
59230b9b | 264 | assert(amount <= buf->start - buf->base); |
2fe58dfd SE |
265 | buf->size+=amount; |
266 | return buf->start-=amount; | |
267 | } | |
268 | ||
1caa23ff | 269 | void *buf_unappend(struct buffer_if *buf, int32_t amount) { |
2fe58dfd SE |
270 | if (buf->size < amount) return 0; |
271 | return buf->start+(buf->size-=amount); | |
272 | } | |
273 | ||
1caa23ff | 274 | void *buf_unprepend(struct buffer_if *buf, int32_t amount) { |
2fe58dfd | 275 | void *p; |
20138876 | 276 | if (buf->size < amount) return 0; |
2fe58dfd SE |
277 | p=buf->start; |
278 | buf->start+=amount; | |
279 | buf->size-=amount; | |
280 | return p; | |
281 | } | |
282 | ||
283 | /* Append a two-byte length and the string to the buffer. Length is in | |
284 | network byte order. */ | |
fe5e9cc4 | 285 | void buf_append_string(struct buffer_if *buf, cstring_t s) |
2fe58dfd | 286 | { |
1caa23ff | 287 | size_t len; |
2fe58dfd SE |
288 | |
289 | len=strlen(s); | |
59230b9b | 290 | /* fixme: if string is longer than 65535, result is a corrupted packet */ |
59635212 | 291 | buf_append_uint16(buf,len); |
2fe58dfd SE |
292 | memcpy(buf_append(buf,len),s,len); |
293 | } | |
294 | ||
1caa23ff | 295 | void buffer_new(struct buffer_if *buf, int32_t len) |
2fe58dfd SE |
296 | { |
297 | buf->free=True; | |
298 | buf->owner=NULL; | |
299 | buf->flags=0; | |
300 | buf->loc.file=NULL; | |
301 | buf->loc.line=0; | |
302 | buf->size=0; | |
303 | buf->len=len; | |
304 | buf->start=NULL; | |
305 | buf->base=safe_malloc(len,"buffer_new"); | |
306 | } | |
307 | ||
28db900b IJ |
308 | void buffer_readonly_view(struct buffer_if *buf, const void *data, int32_t len) |
309 | { | |
310 | buf->free=False; | |
311 | buf->owner="READONLY"; | |
312 | buf->flags=0; | |
313 | buf->loc.file=NULL; | |
314 | buf->loc.line=0; | |
315 | buf->size=buf->len=len; | |
316 | buf->base=buf->start=(uint8_t*)data; | |
317 | } | |
318 | ||
319 | void buffer_readonly_clone(struct buffer_if *out, const struct buffer_if *in) | |
320 | { | |
321 | buffer_readonly_view(out,in->start,in->size); | |
322 | } | |
323 | ||
05f39b4d IJ |
324 | void buffer_copy(struct buffer_if *dst, const struct buffer_if *src) |
325 | { | |
326 | if (dst->len < src->len) { | |
327 | dst->base=realloc(dst->base,src->len); | |
328 | if (!dst->base) fatal_perror("buffer_copy"); | |
329 | dst->len = src->len; | |
330 | } | |
331 | dst->start = dst->base + (src->start - src->base); | |
332 | dst->size = src->size; | |
333 | memcpy(dst->start, src->start, dst->size); | |
334 | } | |
335 | ||
2fe58dfd SE |
336 | static list_t *buffer_apply(closure_t *self, struct cloc loc, dict_t *context, |
337 | list_t *args) | |
338 | { | |
339 | struct buffer *st; | |
340 | item_t *item; | |
341 | dict_t *dict; | |
342 | bool_t lockdown=False; | |
4efd681a | 343 | uint32_t len=DEFAULT_BUFFER_SIZE; |
2fe58dfd SE |
344 | |
345 | st=safe_malloc(sizeof(*st),"buffer_apply"); | |
346 | st->cl.description="buffer"; | |
347 | st->cl.type=CL_BUFFER; | |
348 | st->cl.apply=NULL; | |
349 | st->cl.interface=&st->ops; | |
2fe58dfd SE |
350 | |
351 | /* First argument, if present, is buffer length */ | |
352 | item=list_elem(args,0); | |
353 | if (item) { | |
354 | if (item->type!=t_number) { | |
355 | cfgfatal(st->ops.loc,"buffer","first parameter must be a " | |
356 | "number (buffer size)\n"); | |
357 | } | |
4efd681a SE |
358 | len=item->data.number; |
359 | if (len<MIN_BUFFER_SIZE) { | |
2fe58dfd SE |
360 | cfgfatal(st->ops.loc,"buffer","ludicrously small buffer size\n"); |
361 | } | |
4efd681a | 362 | if (len>MAX_BUFFER_SIZE) { |
2fe58dfd SE |
363 | cfgfatal(st->ops.loc,"buffer","ludicrously large buffer size\n"); |
364 | } | |
365 | } | |
366 | /* Second argument, if present, is a dictionary */ | |
367 | item=list_elem(args,1); | |
368 | if (item) { | |
369 | if (item->type!=t_dict) { | |
370 | cfgfatal(st->ops.loc,"buffer","second parameter must be a " | |
371 | "dictionary\n"); | |
372 | } | |
373 | dict=item->data.dict; | |
374 | lockdown=dict_read_bool(dict,"lockdown",False,"buffer",st->ops.loc, | |
375 | False); | |
376 | } | |
377 | ||
4efd681a | 378 | buffer_new(&st->ops,len); |
2fe58dfd | 379 | if (lockdown) { |
70dc107b | 380 | /* XXX mlock the buffer if possible */ |
2fe58dfd SE |
381 | } |
382 | ||
383 | return new_closure(&st->cl); | |
384 | } | |
385 | ||
8534d602 IJ |
386 | void send_nak(const struct comm_addr *dest, uint32_t our_index, |
387 | uint32_t their_index, uint32_t msgtype, | |
388 | struct buffer_if *buf, const char *logwhy) | |
389 | { | |
3abd18e8 | 390 | buffer_init(buf,calculate_max_start_pad()); |
8534d602 IJ |
391 | buf_append_uint32(buf,their_index); |
392 | buf_append_uint32(buf,our_index); | |
393 | buf_append_uint32(buf,LABEL_NAK); | |
394 | if (logwhy) | |
395 | Message(M_INFO,"%s: %08"PRIx32"<-%08"PRIx32": %08"PRIx32":" | |
396 | " %s; sending NAK\n", | |
397 | dest->comm->addr_to_string(dest->comm->st,dest), | |
398 | our_index, their_index, msgtype, logwhy); | |
399 | dest->comm->sendmsg(dest->comm->st, buf, dest); | |
400 | } | |
401 | ||
5ad34db2 IJ |
402 | int consttime_memeq(const void *s1in, const void *s2in, size_t n) |
403 | { | |
404 | const uint8_t *s1=s1in, *s2=s2in; | |
405 | register volatile uint8_t accumulator=0; | |
406 | ||
407 | while (n-- > 0) { | |
408 | accumulator |= (*s1++ ^ *s2++); | |
409 | } | |
410 | accumulator |= accumulator >> 4; /* constant-time */ | |
411 | accumulator |= accumulator >> 2; /* boolean canonicalisation */ | |
412 | accumulator |= accumulator >> 1; | |
413 | accumulator &= 1; | |
414 | accumulator ^= 1; | |
415 | return accumulator; | |
416 | } | |
417 | ||
2fe58dfd SE |
418 | void util_module(dict_t *dict) |
419 | { | |
2fe58dfd SE |
420 | add_closure(dict,"sysbuffer",buffer_apply); |
421 | } | |
3abd18e8 IJ |
422 | |
423 | void update_max_start_pad(int32_t *our_module_global, int32_t our_instance) | |
424 | { | |
425 | if (*our_module_global < our_instance) | |
426 | *our_module_global=our_instance; | |
427 | } | |
428 | ||
429 | int32_t transform_max_start_pad, comm_max_start_pad; | |
430 | ||
431 | int32_t calculate_max_start_pad(void) | |
432 | { | |
433 | return | |
434 | site_max_start_pad + | |
435 | transform_max_start_pad + | |
436 | comm_max_start_pad; | |
437 | } |