2 * Platform-independent routines shared between all PuTTY programs.
14 * Parse a string block size specification. This is approximately a
15 * subset of the block size specs supported by GNU fileutils:
19 * All numbers are decimal, and suffixes refer to powers of two.
22 unsigned long parse_blocksize(const char *bs
)
25 unsigned long r
= strtoul(bs
, &suf
, 10);
27 while (*suf
&& isspace((unsigned char)*suf
)) suf
++;
36 r
*= 1024ul * 1024ul * 1024ul;
47 * Parse a ^C style character specification.
48 * Returns NULL in `next' if we didn't recognise it as a control character,
49 * in which case `c' should be ignored.
50 * The precise current parsing is an oddity inherited from the terminal
51 * answerback-string parsing code. All sequences start with ^; all except
52 * ^<123> are two characters. The ones that are worth keeping are probably:
56 * <num> specified by number (decimal, 0octal, 0xHEX)
59 char ctrlparse(char *s
, char **next
)
68 } else if (*s
== '<') {
70 c
= (char)strtol(s
, next
, 0);
71 if ((*next
== s
) || (**next
!= '>')) {
76 } else if (*s
>= 'a' && *s
<= 'z') {
79 } else if ((*s
>= '@' && *s
<= '_') || *s
== '?' || (*s
& 0x80)) {
82 } else if (*s
== '~') {
90 prompts_t
*new_prompts(void *frontend
)
92 prompts_t
*p
= snew(prompts_t
);
95 p
->frontend
= frontend
;
97 p
->to_server
= TRUE
; /* to be on the safe side */
98 p
->name
= p
->instruction
= NULL
;
99 p
->name_reqd
= p
->instr_reqd
= FALSE
;
102 void add_prompt(prompts_t
*p
, char *promptstr
, int echo
)
104 prompt_t
*pr
= snew(prompt_t
);
105 pr
->prompt
= promptstr
;
110 p
->prompts
= sresize(p
->prompts
, p
->n_prompts
, prompt_t
*);
111 p
->prompts
[p
->n_prompts
-1] = pr
;
113 void prompt_ensure_result_size(prompt_t
*pr
, int newlen
)
115 if ((int)pr
->resultsize
< newlen
) {
117 newlen
= newlen
* 5 / 4 + 512; /* avoid too many small allocs */
120 * We don't use sresize / realloc here, because we will be
121 * storing sensitive stuff like passwords in here, and we want
122 * to make sure that the data doesn't get copied around in
123 * memory without the old copy being destroyed.
125 newbuf
= snewn(newlen
, char);
126 memcpy(newbuf
, pr
->result
, pr
->resultsize
);
127 memset(pr
->result
, '\0', pr
->resultsize
);
130 pr
->resultsize
= newlen
;
133 void prompt_set_result(prompt_t
*pr
, const char *newstr
)
135 prompt_ensure_result_size(pr
, strlen(newstr
) + 1);
136 strcpy(pr
->result
, newstr
);
138 void free_prompts(prompts_t
*p
)
141 for (i
=0; i
< p
->n_prompts
; i
++) {
142 prompt_t
*pr
= p
->prompts
[i
];
143 memset(pr
->result
, 0, pr
->resultsize
); /* burn the evidence */
150 sfree(p
->instruction
);
154 /* ----------------------------------------------------------------------
155 * String handling routines.
158 char *dupstr(const char *s
)
163 p
= snewn(len
+ 1, char);
169 /* Allocate the concatenation of N strings. Terminate arg list with NULL. */
170 char *dupcat(const char *s1
, ...)
179 sn
= va_arg(ap
, char *);
186 p
= snewn(len
+ 1, char);
192 sn
= va_arg(ap
, char *);
203 void burnstr(char *string
) /* sfree(str), only clear it first */
206 memset(string
, 0, strlen(string
));
212 * Do an sprintf(), but into a custom-allocated buffer.
214 * Currently I'm doing this via vsnprintf. This has worked so far,
215 * but it's not good, because vsnprintf is not available on all
216 * platforms. There's an ifdef to use `_vsnprintf', which seems
217 * to be the local name for it on Windows. Other platforms may
218 * lack it completely, in which case it'll be time to rewrite
219 * this function in a totally different way.
221 * The only `properly' portable solution I can think of is to
222 * implement my own format string scanner, which figures out an
223 * upper bound for the length of each formatting directive,
224 * allocates the buffer as it goes along, and calls sprintf() to
225 * actually process each directive. If I ever need to actually do
226 * this, some caveats:
228 * - It's very hard to find a reliable upper bound for
229 * floating-point values. %f, in particular, when supplied with
230 * a number near to the upper or lower limit of representable
231 * numbers, could easily take several hundred characters. It's
232 * probably feasible to predict this statically using the
233 * constants in <float.h>, or even to predict it dynamically by
234 * looking at the exponent of the specific float provided, but
237 * - Don't forget to _check_, after calling sprintf, that it's
238 * used at most the amount of space we had available.
240 * - Fault any formatting directive we don't fully understand. The
241 * aim here is to _guarantee_ that we never overflow the buffer,
242 * because this is a security-critical function. If we see a
243 * directive we don't know about, we should panic and die rather
246 char *dupprintf(const char *fmt
, ...)
251 ret
= dupvprintf(fmt
, ap
);
255 char *dupvprintf(const char *fmt
, va_list ap
)
260 buf
= snewn(512, char);
265 #define vsnprintf _vsnprintf
268 /* Use the `va_copy' macro mandated by C99, if present.
269 * XXX some environments may have this as __va_copy() */
272 len
= vsnprintf(buf
, size
, fmt
, aq
);
275 /* Ugh. No va_copy macro, so do something nasty.
276 * Technically, you can't reuse a va_list like this: it is left
277 * unspecified whether advancing a va_list pointer modifies its
278 * value or something it points to, so on some platforms calling
279 * vsnprintf twice on the same va_list might fail hideously
280 * (indeed, it has been observed to).
281 * XXX the autoconf manual suggests that using memcpy() will give
282 * "maximum portability". */
283 len
= vsnprintf(buf
, size
, fmt
, ap
);
285 if (len
>= 0 && len
< size
) {
286 /* This is the C99-specified criterion for snprintf to have
287 * been completely successful. */
289 } else if (len
> 0) {
290 /* This is the C99 error condition: the returned length is
291 * the required buffer size not counting the NUL. */
294 /* This is the pre-C99 glibc error condition: <0 means the
295 * buffer wasn't big enough, so we enlarge it a bit and hope. */
298 buf
= sresize(buf
, size
, char);
303 * Read an entire line of text from a file. Return a buffer
304 * malloced to be as big as necessary (caller must free).
306 char *fgetline(FILE *fp
)
308 char *ret
= snewn(512, char);
309 int size
= 512, len
= 0;
310 while (fgets(ret
+ len
, size
- len
, fp
)) {
311 len
+= strlen(ret
+ len
);
312 if (ret
[len
-1] == '\n')
313 break; /* got a newline, we're done */
315 ret
= sresize(ret
, size
, char);
317 if (len
== 0) { /* first fgets returned NULL */
325 /* ----------------------------------------------------------------------
326 * Base64 encoding routine. This is required in public-key writing
327 * but also in HTTP proxy handling, so it's centralised here.
330 void base64_encode_atom(unsigned char *data
, int n
, char *out
)
332 static const char base64_chars
[] =
333 "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
337 word
= data
[0] << 16;
339 word
|= data
[1] << 8;
342 out
[0] = base64_chars
[(word
>> 18) & 0x3F];
343 out
[1] = base64_chars
[(word
>> 12) & 0x3F];
345 out
[2] = base64_chars
[(word
>> 6) & 0x3F];
349 out
[3] = base64_chars
[word
& 0x3F];
354 /* ----------------------------------------------------------------------
355 * Generic routines to deal with send buffers: a linked list of
356 * smallish blocks, with the operations
358 * - add an arbitrary amount of data to the end of the list
359 * - remove the first N bytes from the list
360 * - return a (pointer,length) pair giving some initial data in
361 * the list, suitable for passing to a send or write system
363 * - retrieve a larger amount of initial data from the list
364 * - return the current size of the buffer chain in bytes
367 #define BUFFER_GRANULE 512
369 struct bufchain_granule
{
370 struct bufchain_granule
*next
;
372 char buf
[BUFFER_GRANULE
];
375 void bufchain_init(bufchain
*ch
)
377 ch
->head
= ch
->tail
= NULL
;
381 void bufchain_clear(bufchain
*ch
)
383 struct bufchain_granule
*b
;
386 ch
->head
= ch
->head
->next
;
393 int bufchain_size(bufchain
*ch
)
395 return ch
->buffersize
;
398 void bufchain_add(bufchain
*ch
, const void *data
, int len
)
400 const char *buf
= (const char *)data
;
402 if (len
== 0) return;
404 ch
->buffersize
+= len
;
406 if (ch
->tail
&& ch
->tail
->buflen
< BUFFER_GRANULE
) {
407 int copylen
= min(len
, BUFFER_GRANULE
- ch
->tail
->buflen
);
408 memcpy(ch
->tail
->buf
+ ch
->tail
->buflen
, buf
, copylen
);
411 ch
->tail
->buflen
+= copylen
;
414 int grainlen
= min(len
, BUFFER_GRANULE
);
415 struct bufchain_granule
*newbuf
;
416 newbuf
= snew(struct bufchain_granule
);
418 newbuf
->buflen
= grainlen
;
419 memcpy(newbuf
->buf
, buf
, grainlen
);
423 ch
->tail
->next
= newbuf
;
425 ch
->head
= ch
->tail
= newbuf
;
431 void bufchain_consume(bufchain
*ch
, int len
)
433 struct bufchain_granule
*tmp
;
435 assert(ch
->buffersize
>= len
);
438 assert(ch
->head
!= NULL
);
439 if (remlen
>= ch
->head
->buflen
- ch
->head
->bufpos
) {
440 remlen
= ch
->head
->buflen
- ch
->head
->bufpos
;
442 ch
->head
= tmp
->next
;
447 ch
->head
->bufpos
+= remlen
;
448 ch
->buffersize
-= remlen
;
453 void bufchain_prefix(bufchain
*ch
, void **data
, int *len
)
455 *len
= ch
->head
->buflen
- ch
->head
->bufpos
;
456 *data
= ch
->head
->buf
+ ch
->head
->bufpos
;
459 void bufchain_fetch(bufchain
*ch
, void *data
, int len
)
461 struct bufchain_granule
*tmp
;
462 char *data_c
= (char *)data
;
466 assert(ch
->buffersize
>= len
);
471 if (remlen
>= tmp
->buflen
- tmp
->bufpos
)
472 remlen
= tmp
->buflen
- tmp
->bufpos
;
473 memcpy(data_c
, tmp
->buf
+ tmp
->bufpos
, remlen
);
481 /* ----------------------------------------------------------------------
482 * My own versions of malloc, realloc and free. Because I want
483 * malloc and realloc to bomb out and exit the program if they run
484 * out of memory, realloc to reliably call malloc if passed a NULL
485 * pointer, and free to reliably do nothing if passed a NULL
486 * pointer. We can also put trace printouts in, if we need to; and
487 * we can also replace the allocator with an ElectricFence-like
492 void *minefield_c_malloc(size_t size
);
493 void minefield_c_free(void *p
);
494 void *minefield_c_realloc(void *p
, size_t size
);
498 static FILE *fp
= NULL
;
500 static char *mlog_file
= NULL
;
501 static int mlog_line
= 0;
503 void mlog(char *file
, int line
)
508 fp
= fopen("putty_mem.log", "w");
509 setvbuf(fp
, NULL
, _IONBF
, BUFSIZ
);
512 fprintf(fp
, "%s:%d: ", file
, line
);
516 void *safemalloc(size_t n
, size_t size
)
520 if (n
> INT_MAX
/ size
) {
524 if (size
== 0) size
= 1;
526 p
= minefield_c_malloc(size
);
535 sprintf(str
, "Out of memory! (%s:%d, size=%d)",
536 mlog_file
, mlog_line
, size
);
537 fprintf(fp
, "*** %s\n", str
);
540 strcpy(str
, "Out of memory!");
546 fprintf(fp
, "malloc(%d) returns %p\n", size
, p
);
551 void *saferealloc(void *ptr
, size_t n
, size_t size
)
555 if (n
> INT_MAX
/ size
) {
561 p
= minefield_c_malloc(size
);
567 p
= minefield_c_realloc(ptr
, size
);
569 p
= realloc(ptr
, size
);
577 sprintf(str
, "Out of memory! (%s:%d, size=%d)",
578 mlog_file
, mlog_line
, size
);
579 fprintf(fp
, "*** %s\n", str
);
582 strcpy(str
, "Out of memory!");
588 fprintf(fp
, "realloc(%p,%d) returns %p\n", ptr
, size
, p
);
593 void safefree(void *ptr
)
598 fprintf(fp
, "free(%p)\n", ptr
);
601 minefield_c_free(ptr
);
608 fprintf(fp
, "freeing null pointer - no action taken\n");
612 /* ----------------------------------------------------------------------
613 * Debugging routines.
617 extern void dputs(char *); /* defined in per-platform *misc.c */
619 void debug_printf(char *fmt
, ...)
625 buf
= dupvprintf(fmt
, ap
);
632 void debug_memdump(void *buf
, int len
, int L
)
635 unsigned char *p
= buf
;
639 debug_printf("\t%d (0x%x) bytes:\n", len
, len
);
640 delta
= 15 & (unsigned long int) p
;
644 for (; 0 < len
; p
+= 16, len
-= 16) {
647 debug_printf("%p: ", p
);
648 strcpy(foo
, "................"); /* sixteen dots */
649 for (i
= 0; i
< 16 && i
< len
; ++i
) {
650 if (&p
[i
] < (unsigned char *) buf
) {
651 dputs(" "); /* 3 spaces */
654 debug_printf("%c%02.2x",
655 &p
[i
] != (unsigned char *) buf
656 && i
% 4 ?
'.' : ' ', p
[i
]
658 if (p
[i
] >= ' ' && p
[i
] <= '~')
659 foo
[i
] = (char) p
[i
];
663 debug_printf("%*s%s\n", (16 - i
) * 3 + 2, "", foo
);
667 #endif /* def DEBUG */
670 * Determine whether or not a Conf represents a session which can
671 * sensibly be launched right now.
673 int conf_launchable(Conf
*conf
)
675 if (conf_get_int(conf
, CONF_protocol
) == PROT_SERIAL
)
676 return conf_get_str(conf
, CONF_serline
)[0] != 0;
678 return conf_get_str(conf
, CONF_host
)[0] != 0;
681 char const *conf_dest(Conf
*conf
)
683 if (conf_get_int(conf
, CONF_protocol
) == PROT_SERIAL
)
684 return conf_get_str(conf
, CONF_serline
);
686 return conf_get_str(conf
, CONF_host
);