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v3.5.6
  1/*********************************************************************
  2 *
  3 * Filename:      parameters.c
  4 * Version:       1.0
  5 * Description:   A more general way to handle (pi,pl,pv) parameters
  6 * Status:        Experimental.
  7 * Author:        Dag Brattli <dagb@cs.uit.no>
  8 * Created at:    Mon Jun  7 10:25:11 1999
  9 * Modified at:   Sun Jan 30 14:08:39 2000
 10 * Modified by:   Dag Brattli <dagb@cs.uit.no>
 11 *
 12 *     Copyright (c) 1999-2000 Dag Brattli, All Rights Reserved.
 13 *
 14 *     This program is free software; you can redistribute it and/or
 15 *     modify it under the terms of the GNU General Public License as
 16 *     published by the Free Software Foundation; either version 2 of
 17 *     the License, or (at your option) any later version.
 18 *
 19 *     This program is distributed in the hope that it will be useful,
 20 *     but WITHOUT ANY WARRANTY; without even the implied warranty of
 21 *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 22 *     GNU General Public License for more details.
 23 *
 24 *     You should have received a copy of the GNU General Public License
 25 *     along with this program; if not, write to the Free Software
 26 *     Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 27 *     MA 02111-1307 USA
 28 *
 29 ********************************************************************/
 30
 31#include <linux/types.h>
 32#include <linux/module.h>
 33
 34#include <asm/unaligned.h>
 35#include <asm/byteorder.h>
 36
 37#include <net/irda/irda.h>
 38#include <net/irda/parameters.h>
 39
 40static int irda_extract_integer(void *self, __u8 *buf, int len, __u8 pi,
 41				PV_TYPE type, PI_HANDLER func);
 42static int irda_extract_string(void *self, __u8 *buf, int len, __u8 pi,
 43			       PV_TYPE type, PI_HANDLER func);
 44static int irda_extract_octseq(void *self, __u8 *buf, int len, __u8 pi,
 45			       PV_TYPE type, PI_HANDLER func);
 46static int irda_extract_no_value(void *self, __u8 *buf, int len, __u8 pi,
 47				 PV_TYPE type, PI_HANDLER func);
 48
 49static int irda_insert_integer(void *self, __u8 *buf, int len, __u8 pi,
 50			       PV_TYPE type, PI_HANDLER func);
 51static int irda_insert_no_value(void *self, __u8 *buf, int len, __u8 pi,
 52				PV_TYPE type, PI_HANDLER func);
 53
 54static int irda_param_unpack(__u8 *buf, char *fmt, ...);
 55
 56/* Parameter value call table. Must match PV_TYPE */
 57static PV_HANDLER pv_extract_table[] = {
 58	irda_extract_integer, /* Handler for any length integers */
 59	irda_extract_integer, /* Handler for 8  bits integers */
 60	irda_extract_integer, /* Handler for 16 bits integers */
 61	irda_extract_string,  /* Handler for strings */
 62	irda_extract_integer, /* Handler for 32 bits integers */
 63	irda_extract_octseq,  /* Handler for octet sequences */
 64	irda_extract_no_value /* Handler for no value parameters */
 65};
 66
 67static PV_HANDLER pv_insert_table[] = {
 68	irda_insert_integer, /* Handler for any length integers */
 69	irda_insert_integer, /* Handler for 8  bits integers */
 70	irda_insert_integer, /* Handler for 16 bits integers */
 71	NULL,                /* Handler for strings */
 72	irda_insert_integer, /* Handler for 32 bits integers */
 73	NULL,                /* Handler for octet sequences */
 74	irda_insert_no_value /* Handler for no value parameters */
 75};
 76
 77/*
 78 * Function irda_insert_no_value (self, buf, len, pi, type, func)
 79 */
 80static int irda_insert_no_value(void *self, __u8 *buf, int len, __u8 pi,
 81				PV_TYPE type, PI_HANDLER func)
 82{
 83	irda_param_t p;
 84	int ret;
 85
 86	p.pi = pi;
 87	p.pl = 0;
 88
 89	/* Call handler for this parameter */
 90	ret = (*func)(self, &p, PV_GET);
 91
 92	/* Extract values anyway, since handler may need them */
 93	irda_param_pack(buf, "bb", p.pi, p.pl);
 94
 95	if (ret < 0)
 96		return ret;
 97
 98	return 2; /* Inserted pl+2 bytes */
 99}
100
101/*
102 * Function irda_extract_no_value (self, buf, len, type, func)
103 *
104 *    Extracts a parameter without a pv field (pl=0)
105 *
106 */
107static int irda_extract_no_value(void *self, __u8 *buf, int len, __u8 pi,
108				 PV_TYPE type, PI_HANDLER func)
109{
110	irda_param_t p;
111	int ret;
112
113	/* Extract values anyway, since handler may need them */
114	irda_param_unpack(buf, "bb", &p.pi, &p.pl);
115
116	/* Call handler for this parameter */
117	ret = (*func)(self, &p, PV_PUT);
118
119	if (ret < 0)
120		return ret;
121
122	return 2; /* Extracted pl+2 bytes */
123}
124
125/*
126 * Function irda_insert_integer (self, buf, len, pi, type, func)
127 */
128static int irda_insert_integer(void *self, __u8 *buf, int len, __u8 pi,
129			       PV_TYPE type, PI_HANDLER func)
130{
131	irda_param_t p;
132	int n = 0;
133	int err;
134
135	p.pi = pi;             /* In case handler needs to know */
136	p.pl = type & PV_MASK; /* The integer type codes the length as well */
137	p.pv.i = 0;            /* Clear value */
138
139	/* Call handler for this parameter */
140	err = (*func)(self, &p, PV_GET);
141	if (err < 0)
142		return err;
143
144	/*
145	 * If parameter length is still 0, then (1) this is an any length
146	 * integer, and (2) the handler function does not care which length
147	 * we choose to use, so we pick the one the gives the fewest bytes.
148	 */
149	if (p.pl == 0) {
150		if (p.pv.i < 0xff) {
151			IRDA_DEBUG(2, "%s(), using 1 byte\n", __func__);
152			p.pl = 1;
153		} else if (p.pv.i < 0xffff) {
154			IRDA_DEBUG(2, "%s(), using 2 bytes\n", __func__);
155			p.pl = 2;
156		} else {
157			IRDA_DEBUG(2, "%s(), using 4 bytes\n", __func__);
158			p.pl = 4; /* Default length */
159		}
160	}
161	/* Check if buffer is long enough for insertion */
162	if (len < (2+p.pl)) {
163		IRDA_WARNING("%s: buffer too short for insertion!\n",
164			     __func__);
165		return -1;
166	}
167	IRDA_DEBUG(2, "%s(), pi=%#x, pl=%d, pi=%d\n", __func__,
168		   p.pi, p.pl, p.pv.i);
169	switch (p.pl) {
170	case 1:
171		n += irda_param_pack(buf, "bbb", p.pi, p.pl, (__u8) p.pv.i);
172		break;
173	case 2:
174		if (type & PV_BIG_ENDIAN)
175			p.pv.i = cpu_to_be16((__u16) p.pv.i);
176		else
177			p.pv.i = cpu_to_le16((__u16) p.pv.i);
178		n += irda_param_pack(buf, "bbs", p.pi, p.pl, (__u16) p.pv.i);
179		break;
180	case 4:
181		if (type & PV_BIG_ENDIAN)
182			cpu_to_be32s(&p.pv.i);
183		else
184			cpu_to_le32s(&p.pv.i);
185		n += irda_param_pack(buf, "bbi", p.pi, p.pl, p.pv.i);
186
187		break;
188	default:
189		IRDA_WARNING("%s: length %d not supported\n",
190			     __func__, p.pl);
191		/* Skip parameter */
192		return -1;
193	}
194
195	return p.pl+2; /* Inserted pl+2 bytes */
196}
197
198/*
199 * Function irda_extract integer (self, buf, len, pi, type, func)
200 *
201 *    Extract a possibly variable length integer from buffer, and call
202 *    handler for processing of the parameter
203 */
204static int irda_extract_integer(void *self, __u8 *buf, int len, __u8 pi,
205				PV_TYPE type, PI_HANDLER func)
206{
207	irda_param_t p;
208	int n = 0;
209	int extract_len;	/* Real length we extract */
210	int err;
211
212	p.pi = pi;     /* In case handler needs to know */
213	p.pl = buf[1]; /* Extract length of value */
214	p.pv.i = 0;    /* Clear value */
215	extract_len = p.pl;	/* Default : extract all */
216
217	/* Check if buffer is long enough for parsing */
218	if (len < (2+p.pl)) {
219		IRDA_WARNING("%s: buffer too short for parsing! "
220			     "Need %d bytes, but len is only %d\n",
221			     __func__, p.pl, len);
222		return -1;
223	}
224
225	/*
226	 * Check that the integer length is what we expect it to be. If the
227	 * handler want a 16 bits integer then a 32 bits is not good enough
228	 * PV_INTEGER means that the handler is flexible.
229	 */
230	if (((type & PV_MASK) != PV_INTEGER) && ((type & PV_MASK) != p.pl)) {
231		IRDA_ERROR("%s: invalid parameter length! "
232			   "Expected %d bytes, but value had %d bytes!\n",
233			   __func__, type & PV_MASK, p.pl);
234
235		/* Most parameters are bit/byte fields or little endian,
236		 * so it's ok to only extract a subset of it (the subset
237		 * that the handler expect). This is necessary, as some
238		 * broken implementations seems to add extra undefined bits.
239		 * If the parameter is shorter than we expect or is big
240		 * endian, we can't play those tricks. Jean II */
241		if((p.pl < (type & PV_MASK)) || (type & PV_BIG_ENDIAN)) {
242			/* Skip parameter */
243			return p.pl+2;
244		} else {
245			/* Extract subset of it, fallthrough */
246			extract_len = type & PV_MASK;
247		}
248	}
249
250
251	switch (extract_len) {
252	case 1:
253		n += irda_param_unpack(buf+2, "b", &p.pv.i);
254		break;
255	case 2:
256		n += irda_param_unpack(buf+2, "s", &p.pv.i);
257		if (type & PV_BIG_ENDIAN)
258			p.pv.i = be16_to_cpu((__u16) p.pv.i);
259		else
260			p.pv.i = le16_to_cpu((__u16) p.pv.i);
261		break;
262	case 4:
263		n += irda_param_unpack(buf+2, "i", &p.pv.i);
264		if (type & PV_BIG_ENDIAN)
265			be32_to_cpus(&p.pv.i);
266		else
267			le32_to_cpus(&p.pv.i);
268		break;
269	default:
270		IRDA_WARNING("%s: length %d not supported\n",
271			     __func__, p.pl);
272
273		/* Skip parameter */
274		return p.pl+2;
275	}
276
277	IRDA_DEBUG(2, "%s(), pi=%#x, pl=%d, pi=%d\n", __func__,
278		   p.pi, p.pl, p.pv.i);
279	/* Call handler for this parameter */
280	err = (*func)(self, &p, PV_PUT);
281	if (err < 0)
282		return err;
283
284	return p.pl+2; /* Extracted pl+2 bytes */
285}
286
287/*
288 * Function irda_extract_string (self, buf, len, type, func)
289 */
290static int irda_extract_string(void *self, __u8 *buf, int len, __u8 pi,
291			       PV_TYPE type, PI_HANDLER func)
292{
293	char str[33];
294	irda_param_t p;
295	int err;
296
297	IRDA_DEBUG(2, "%s()\n", __func__);
298
299	p.pi = pi;     /* In case handler needs to know */
300	p.pl = buf[1]; /* Extract length of value */
301	if (p.pl > 32)
302		p.pl = 32;
303
304	IRDA_DEBUG(2, "%s(), pi=%#x, pl=%d\n", __func__,
305		   p.pi, p.pl);
306
307	/* Check if buffer is long enough for parsing */
308	if (len < (2+p.pl)) {
309		IRDA_WARNING("%s: buffer too short for parsing! "
310			     "Need %d bytes, but len is only %d\n",
311			     __func__, p.pl, len);
312		return -1;
313	}
314
315	/* Should be safe to copy string like this since we have already
316	 * checked that the buffer is long enough */
317	strncpy(str, buf+2, p.pl);
318
319	IRDA_DEBUG(2, "%s(), str=0x%02x 0x%02x\n", __func__,
320		   (__u8) str[0], (__u8) str[1]);
321
322	/* Null terminate string */
323	str[p.pl] = '\0';
324
325	p.pv.c = str; /* Handler will need to take a copy */
326
327	/* Call handler for this parameter */
328	err = (*func)(self, &p, PV_PUT);
329	if (err < 0)
330		return err;
331
332	return p.pl+2; /* Extracted pl+2 bytes */
333}
334
335/*
336 * Function irda_extract_octseq (self, buf, len, type, func)
337 */
338static int irda_extract_octseq(void *self, __u8 *buf, int len, __u8 pi,
339			       PV_TYPE type, PI_HANDLER func)
340{
341	irda_param_t p;
342
343	p.pi = pi;     /* In case handler needs to know */
344	p.pl = buf[1]; /* Extract length of value */
345
346	/* Check if buffer is long enough for parsing */
347	if (len < (2+p.pl)) {
348		IRDA_WARNING("%s: buffer too short for parsing! "
349			     "Need %d bytes, but len is only %d\n",
350			     __func__, p.pl, len);
351		return -1;
352	}
353
354	IRDA_DEBUG(0, "%s(), not impl\n", __func__);
355
356	return p.pl+2; /* Extracted pl+2 bytes */
357}
358
359/*
360 * Function irda_param_pack (skb, fmt, ...)
361 *
362 *    Format:
363 *        'i' = 32 bits integer
364 *        's' = string
365 *
366 */
367int irda_param_pack(__u8 *buf, char *fmt, ...)
368{
369	irda_pv_t arg;
370	va_list args;
371	char *p;
372	int n = 0;
373
374	va_start(args, fmt);
375
376	for (p = fmt; *p != '\0'; p++) {
377		switch (*p) {
378		case 'b':  /* 8 bits unsigned byte */
379			buf[n++] = (__u8)va_arg(args, int);
380			break;
381		case 's':  /* 16 bits unsigned short */
382			arg.i = (__u16)va_arg(args, int);
383			put_unaligned((__u16)arg.i, (__u16 *)(buf+n)); n+=2;
384			break;
385		case 'i':  /* 32 bits unsigned integer */
386			arg.i = va_arg(args, __u32);
387			put_unaligned(arg.i, (__u32 *)(buf+n)); n+=4;
388			break;
389#if 0
390		case 'c': /* \0 terminated string */
391			arg.c = va_arg(args, char *);
392			strcpy(buf+n, arg.c);
393			n += strlen(arg.c) + 1;
394			break;
395#endif
396		default:
397			va_end(args);
398			return -1;
399		}
400	}
401	va_end(args);
402
403	return 0;
404}
405EXPORT_SYMBOL(irda_param_pack);
406
407/*
408 * Function irda_param_unpack (skb, fmt, ...)
409 */
410static int irda_param_unpack(__u8 *buf, char *fmt, ...)
411{
412	irda_pv_t arg;
413	va_list args;
414	char *p;
415	int n = 0;
416
417	va_start(args, fmt);
418
419	for (p = fmt; *p != '\0'; p++) {
420		switch (*p) {
421		case 'b':  /* 8 bits byte */
422			arg.ip = va_arg(args, __u32 *);
423			*arg.ip = buf[n++];
424			break;
425		case 's':  /* 16 bits short */
426			arg.ip = va_arg(args, __u32 *);
427			*arg.ip = get_unaligned((__u16 *)(buf+n)); n+=2;
428			break;
429		case 'i':  /* 32 bits unsigned integer */
430			arg.ip = va_arg(args, __u32 *);
431			*arg.ip = get_unaligned((__u32 *)(buf+n)); n+=4;
432			break;
433#if 0
434		case 'c':   /* \0 terminated string */
435			arg.c = va_arg(args, char *);
436			strcpy(arg.c, buf+n);
437			n += strlen(arg.c) + 1;
438			break;
439#endif
440		default:
441			va_end(args);
442			return -1;
443		}
444
445	}
446	va_end(args);
447
448	return 0;
449}
450
451/*
452 * Function irda_param_insert (self, pi, buf, len, info)
453 *
454 *    Insert the specified parameter (pi) into buffer. Returns number of
455 *    bytes inserted
456 */
457int irda_param_insert(void *self, __u8 pi, __u8 *buf, int len,
458		      pi_param_info_t *info)
459{
460	pi_minor_info_t *pi_minor_info;
461	__u8 pi_minor;
462	__u8 pi_major;
463	int type;
464	int ret = -1;
465	int n = 0;
466
467	IRDA_ASSERT(buf != NULL, return ret;);
468	IRDA_ASSERT(info != NULL, return ret;);
469
470	pi_minor = pi & info->pi_mask;
471	pi_major = pi >> info->pi_major_offset;
472
473	/* Check if the identifier value (pi) is valid */
474	if ((pi_major > info->len-1) ||
475	    (pi_minor > info->tables[pi_major].len-1))
476	{
477		IRDA_DEBUG(0, "%s(), no handler for parameter=0x%02x\n",
478			   __func__, pi);
479
480		/* Skip this parameter */
481		return -1;
482	}
483
484	/* Lookup the info on how to parse this parameter */
485	pi_minor_info = &info->tables[pi_major].pi_minor_call_table[pi_minor];
486
487	/* Find expected data type for this parameter identifier (pi)*/
488	type = pi_minor_info->type;
489
490	/*  Check if handler has been implemented */
491	if (!pi_minor_info->func) {
492		IRDA_MESSAGE("%s: no handler for pi=%#x\n", __func__, pi);
 
493		/* Skip this parameter */
494		return -1;
495	}
496
497	/* Insert parameter value */
498	ret = (*pv_insert_table[type & PV_MASK])(self, buf+n, len, pi, type,
499						 pi_minor_info->func);
500	return ret;
501}
502EXPORT_SYMBOL(irda_param_insert);
503
504/*
505 * Function irda_param_extract (self, buf, len, info)
506 *
507 *    Parse all parameters. If len is correct, then everything should be
508 *    safe. Returns the number of bytes that was parsed
509 *
510 */
511static int irda_param_extract(void *self, __u8 *buf, int len,
512			      pi_param_info_t *info)
513{
514	pi_minor_info_t *pi_minor_info;
515	__u8 pi_minor;
516	__u8 pi_major;
517	int type;
518	int ret = -1;
519	int n = 0;
520
521	IRDA_ASSERT(buf != NULL, return ret;);
522	IRDA_ASSERT(info != NULL, return ret;);
523
524	pi_minor = buf[n] & info->pi_mask;
525	pi_major = buf[n] >> info->pi_major_offset;
526
527	/* Check if the identifier value (pi) is valid */
528	if ((pi_major > info->len-1) ||
529	    (pi_minor > info->tables[pi_major].len-1))
530	{
531		IRDA_DEBUG(0, "%s(), no handler for parameter=0x%02x\n",
532			   __func__, buf[0]);
533
534		/* Skip this parameter */
535		return 2 + buf[n + 1];  /* Continue */
536	}
537
538	/* Lookup the info on how to parse this parameter */
539	pi_minor_info = &info->tables[pi_major].pi_minor_call_table[pi_minor];
540
541	/* Find expected data type for this parameter identifier (pi)*/
542	type = pi_minor_info->type;
543
544	IRDA_DEBUG(3, "%s(), pi=[%d,%d], type=%d\n", __func__,
545		   pi_major, pi_minor, type);
546
547	/*  Check if handler has been implemented */
548	if (!pi_minor_info->func) {
549		IRDA_MESSAGE("%s: no handler for pi=%#x\n",
550			     __func__, buf[n]);
551		/* Skip this parameter */
552		return 2 + buf[n + 1]; /* Continue */
553	}
554
555	/* Parse parameter value */
556	ret = (*pv_extract_table[type & PV_MASK])(self, buf+n, len, buf[n],
557						  type, pi_minor_info->func);
558	return ret;
559}
560
561/*
562 * Function irda_param_extract_all (self, buf, len, info)
563 *
564 *    Parse all parameters. If len is correct, then everything should be
565 *    safe. Returns the number of bytes that was parsed
566 *
567 */
568int irda_param_extract_all(void *self, __u8 *buf, int len,
569			   pi_param_info_t *info)
570{
571	int ret = -1;
572	int n = 0;
573
574	IRDA_ASSERT(buf != NULL, return ret;);
575	IRDA_ASSERT(info != NULL, return ret;);
576
577	/*
578	 * Parse all parameters. Each parameter must be at least two bytes
579	 * long or else there is no point in trying to parse it
580	 */
581	while (len > 2) {
582		ret = irda_param_extract(self, buf+n, len, info);
583		if (ret < 0)
584			return ret;
585
586		n += ret;
587		len -= ret;
588	}
589	return n;
590}
591EXPORT_SYMBOL(irda_param_extract_all);
v4.6
  1/*********************************************************************
  2 *
  3 * Filename:      parameters.c
  4 * Version:       1.0
  5 * Description:   A more general way to handle (pi,pl,pv) parameters
  6 * Status:        Experimental.
  7 * Author:        Dag Brattli <dagb@cs.uit.no>
  8 * Created at:    Mon Jun  7 10:25:11 1999
  9 * Modified at:   Sun Jan 30 14:08:39 2000
 10 * Modified by:   Dag Brattli <dagb@cs.uit.no>
 11 *
 12 *     Copyright (c) 1999-2000 Dag Brattli, All Rights Reserved.
 13 *
 14 *     This program is free software; you can redistribute it and/or
 15 *     modify it under the terms of the GNU General Public License as
 16 *     published by the Free Software Foundation; either version 2 of
 17 *     the License, or (at your option) any later version.
 18 *
 19 *     This program is distributed in the hope that it will be useful,
 20 *     but WITHOUT ANY WARRANTY; without even the implied warranty of
 21 *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 22 *     GNU General Public License for more details.
 23 *
 24 *     You should have received a copy of the GNU General Public License
 25 *     along with this program; if not, see <http://www.gnu.org/licenses/>.
 
 
 26 *
 27 ********************************************************************/
 28
 29#include <linux/types.h>
 30#include <linux/module.h>
 31
 32#include <asm/unaligned.h>
 33#include <asm/byteorder.h>
 34
 35#include <net/irda/irda.h>
 36#include <net/irda/parameters.h>
 37
 38static int irda_extract_integer(void *self, __u8 *buf, int len, __u8 pi,
 39				PV_TYPE type, PI_HANDLER func);
 40static int irda_extract_string(void *self, __u8 *buf, int len, __u8 pi,
 41			       PV_TYPE type, PI_HANDLER func);
 42static int irda_extract_octseq(void *self, __u8 *buf, int len, __u8 pi,
 43			       PV_TYPE type, PI_HANDLER func);
 44static int irda_extract_no_value(void *self, __u8 *buf, int len, __u8 pi,
 45				 PV_TYPE type, PI_HANDLER func);
 46
 47static int irda_insert_integer(void *self, __u8 *buf, int len, __u8 pi,
 48			       PV_TYPE type, PI_HANDLER func);
 49static int irda_insert_no_value(void *self, __u8 *buf, int len, __u8 pi,
 50				PV_TYPE type, PI_HANDLER func);
 51
 52static int irda_param_unpack(__u8 *buf, char *fmt, ...);
 53
 54/* Parameter value call table. Must match PV_TYPE */
 55static const PV_HANDLER pv_extract_table[] = {
 56	irda_extract_integer, /* Handler for any length integers */
 57	irda_extract_integer, /* Handler for 8  bits integers */
 58	irda_extract_integer, /* Handler for 16 bits integers */
 59	irda_extract_string,  /* Handler for strings */
 60	irda_extract_integer, /* Handler for 32 bits integers */
 61	irda_extract_octseq,  /* Handler for octet sequences */
 62	irda_extract_no_value /* Handler for no value parameters */
 63};
 64
 65static const PV_HANDLER pv_insert_table[] = {
 66	irda_insert_integer, /* Handler for any length integers */
 67	irda_insert_integer, /* Handler for 8  bits integers */
 68	irda_insert_integer, /* Handler for 16 bits integers */
 69	NULL,                /* Handler for strings */
 70	irda_insert_integer, /* Handler for 32 bits integers */
 71	NULL,                /* Handler for octet sequences */
 72	irda_insert_no_value /* Handler for no value parameters */
 73};
 74
 75/*
 76 * Function irda_insert_no_value (self, buf, len, pi, type, func)
 77 */
 78static int irda_insert_no_value(void *self, __u8 *buf, int len, __u8 pi,
 79				PV_TYPE type, PI_HANDLER func)
 80{
 81	irda_param_t p;
 82	int ret;
 83
 84	p.pi = pi;
 85	p.pl = 0;
 86
 87	/* Call handler for this parameter */
 88	ret = (*func)(self, &p, PV_GET);
 89
 90	/* Extract values anyway, since handler may need them */
 91	irda_param_pack(buf, "bb", p.pi, p.pl);
 92
 93	if (ret < 0)
 94		return ret;
 95
 96	return 2; /* Inserted pl+2 bytes */
 97}
 98
 99/*
100 * Function irda_extract_no_value (self, buf, len, type, func)
101 *
102 *    Extracts a parameter without a pv field (pl=0)
103 *
104 */
105static int irda_extract_no_value(void *self, __u8 *buf, int len, __u8 pi,
106				 PV_TYPE type, PI_HANDLER func)
107{
108	irda_param_t p;
109	int ret;
110
111	/* Extract values anyway, since handler may need them */
112	irda_param_unpack(buf, "bb", &p.pi, &p.pl);
113
114	/* Call handler for this parameter */
115	ret = (*func)(self, &p, PV_PUT);
116
117	if (ret < 0)
118		return ret;
119
120	return 2; /* Extracted pl+2 bytes */
121}
122
123/*
124 * Function irda_insert_integer (self, buf, len, pi, type, func)
125 */
126static int irda_insert_integer(void *self, __u8 *buf, int len, __u8 pi,
127			       PV_TYPE type, PI_HANDLER func)
128{
129	irda_param_t p;
130	int n = 0;
131	int err;
132
133	p.pi = pi;             /* In case handler needs to know */
134	p.pl = type & PV_MASK; /* The integer type codes the length as well */
135	p.pv.i = 0;            /* Clear value */
136
137	/* Call handler for this parameter */
138	err = (*func)(self, &p, PV_GET);
139	if (err < 0)
140		return err;
141
142	/*
143	 * If parameter length is still 0, then (1) this is an any length
144	 * integer, and (2) the handler function does not care which length
145	 * we choose to use, so we pick the one the gives the fewest bytes.
146	 */
147	if (p.pl == 0) {
148		if (p.pv.i < 0xff) {
149			pr_debug("%s(), using 1 byte\n", __func__);
150			p.pl = 1;
151		} else if (p.pv.i < 0xffff) {
152			pr_debug("%s(), using 2 bytes\n", __func__);
153			p.pl = 2;
154		} else {
155			pr_debug("%s(), using 4 bytes\n", __func__);
156			p.pl = 4; /* Default length */
157		}
158	}
159	/* Check if buffer is long enough for insertion */
160	if (len < (2+p.pl)) {
161		net_warn_ratelimited("%s: buffer too short for insertion!\n",
162				     __func__);
163		return -1;
164	}
165	pr_debug("%s(), pi=%#x, pl=%d, pi=%d\n", __func__,
166		 p.pi, p.pl, p.pv.i);
167	switch (p.pl) {
168	case 1:
169		n += irda_param_pack(buf, "bbb", p.pi, p.pl, (__u8) p.pv.i);
170		break;
171	case 2:
172		if (type & PV_BIG_ENDIAN)
173			p.pv.i = cpu_to_be16((__u16) p.pv.i);
174		else
175			p.pv.i = cpu_to_le16((__u16) p.pv.i);
176		n += irda_param_pack(buf, "bbs", p.pi, p.pl, (__u16) p.pv.i);
177		break;
178	case 4:
179		if (type & PV_BIG_ENDIAN)
180			cpu_to_be32s(&p.pv.i);
181		else
182			cpu_to_le32s(&p.pv.i);
183		n += irda_param_pack(buf, "bbi", p.pi, p.pl, p.pv.i);
184
185		break;
186	default:
187		net_warn_ratelimited("%s: length %d not supported\n",
188				     __func__, p.pl);
189		/* Skip parameter */
190		return -1;
191	}
192
193	return p.pl+2; /* Inserted pl+2 bytes */
194}
195
196/*
197 * Function irda_extract integer (self, buf, len, pi, type, func)
198 *
199 *    Extract a possibly variable length integer from buffer, and call
200 *    handler for processing of the parameter
201 */
202static int irda_extract_integer(void *self, __u8 *buf, int len, __u8 pi,
203				PV_TYPE type, PI_HANDLER func)
204{
205	irda_param_t p;
206	int n = 0;
207	int extract_len;	/* Real length we extract */
208	int err;
209
210	p.pi = pi;     /* In case handler needs to know */
211	p.pl = buf[1]; /* Extract length of value */
212	p.pv.i = 0;    /* Clear value */
213	extract_len = p.pl;	/* Default : extract all */
214
215	/* Check if buffer is long enough for parsing */
216	if (len < (2+p.pl)) {
217		net_warn_ratelimited("%s: buffer too short for parsing! Need %d bytes, but len is only %d\n",
218				     __func__, p.pl, len);
 
219		return -1;
220	}
221
222	/*
223	 * Check that the integer length is what we expect it to be. If the
224	 * handler want a 16 bits integer then a 32 bits is not good enough
225	 * PV_INTEGER means that the handler is flexible.
226	 */
227	if (((type & PV_MASK) != PV_INTEGER) && ((type & PV_MASK) != p.pl)) {
228		net_err_ratelimited("%s: invalid parameter length! Expected %d bytes, but value had %d bytes!\n",
229				    __func__, type & PV_MASK, p.pl);
 
230
231		/* Most parameters are bit/byte fields or little endian,
232		 * so it's ok to only extract a subset of it (the subset
233		 * that the handler expect). This is necessary, as some
234		 * broken implementations seems to add extra undefined bits.
235		 * If the parameter is shorter than we expect or is big
236		 * endian, we can't play those tricks. Jean II */
237		if((p.pl < (type & PV_MASK)) || (type & PV_BIG_ENDIAN)) {
238			/* Skip parameter */
239			return p.pl+2;
240		} else {
241			/* Extract subset of it, fallthrough */
242			extract_len = type & PV_MASK;
243		}
244	}
245
246
247	switch (extract_len) {
248	case 1:
249		n += irda_param_unpack(buf+2, "b", &p.pv.i);
250		break;
251	case 2:
252		n += irda_param_unpack(buf+2, "s", &p.pv.i);
253		if (type & PV_BIG_ENDIAN)
254			p.pv.i = be16_to_cpu((__u16) p.pv.i);
255		else
256			p.pv.i = le16_to_cpu((__u16) p.pv.i);
257		break;
258	case 4:
259		n += irda_param_unpack(buf+2, "i", &p.pv.i);
260		if (type & PV_BIG_ENDIAN)
261			be32_to_cpus(&p.pv.i);
262		else
263			le32_to_cpus(&p.pv.i);
264		break;
265	default:
266		net_warn_ratelimited("%s: length %d not supported\n",
267				     __func__, p.pl);
268
269		/* Skip parameter */
270		return p.pl+2;
271	}
272
273	pr_debug("%s(), pi=%#x, pl=%d, pi=%d\n", __func__,
274		 p.pi, p.pl, p.pv.i);
275	/* Call handler for this parameter */
276	err = (*func)(self, &p, PV_PUT);
277	if (err < 0)
278		return err;
279
280	return p.pl+2; /* Extracted pl+2 bytes */
281}
282
283/*
284 * Function irda_extract_string (self, buf, len, type, func)
285 */
286static int irda_extract_string(void *self, __u8 *buf, int len, __u8 pi,
287			       PV_TYPE type, PI_HANDLER func)
288{
289	char str[33];
290	irda_param_t p;
291	int err;
292
 
 
293	p.pi = pi;     /* In case handler needs to know */
294	p.pl = buf[1]; /* Extract length of value */
295	if (p.pl > 32)
296		p.pl = 32;
297
298	pr_debug("%s(), pi=%#x, pl=%d\n", __func__,
299		 p.pi, p.pl);
300
301	/* Check if buffer is long enough for parsing */
302	if (len < (2+p.pl)) {
303		net_warn_ratelimited("%s: buffer too short for parsing! Need %d bytes, but len is only %d\n",
304				     __func__, p.pl, len);
 
305		return -1;
306	}
307
308	/* Should be safe to copy string like this since we have already
309	 * checked that the buffer is long enough */
310	strncpy(str, buf+2, p.pl);
311
312	pr_debug("%s(), str=0x%02x 0x%02x\n",
313		 __func__, (__u8)str[0], (__u8)str[1]);
314
315	/* Null terminate string */
316	str[p.pl] = '\0';
317
318	p.pv.c = str; /* Handler will need to take a copy */
319
320	/* Call handler for this parameter */
321	err = (*func)(self, &p, PV_PUT);
322	if (err < 0)
323		return err;
324
325	return p.pl+2; /* Extracted pl+2 bytes */
326}
327
328/*
329 * Function irda_extract_octseq (self, buf, len, type, func)
330 */
331static int irda_extract_octseq(void *self, __u8 *buf, int len, __u8 pi,
332			       PV_TYPE type, PI_HANDLER func)
333{
334	irda_param_t p;
335
336	p.pi = pi;     /* In case handler needs to know */
337	p.pl = buf[1]; /* Extract length of value */
338
339	/* Check if buffer is long enough for parsing */
340	if (len < (2+p.pl)) {
341		net_warn_ratelimited("%s: buffer too short for parsing! Need %d bytes, but len is only %d\n",
342				     __func__, p.pl, len);
 
343		return -1;
344	}
345
346	pr_debug("%s(), not impl\n", __func__);
347
348	return p.pl+2; /* Extracted pl+2 bytes */
349}
350
351/*
352 * Function irda_param_pack (skb, fmt, ...)
353 *
354 *    Format:
355 *        'i' = 32 bits integer
356 *        's' = string
357 *
358 */
359int irda_param_pack(__u8 *buf, char *fmt, ...)
360{
361	irda_pv_t arg;
362	va_list args;
363	char *p;
364	int n = 0;
365
366	va_start(args, fmt);
367
368	for (p = fmt; *p != '\0'; p++) {
369		switch (*p) {
370		case 'b':  /* 8 bits unsigned byte */
371			buf[n++] = (__u8)va_arg(args, int);
372			break;
373		case 's':  /* 16 bits unsigned short */
374			arg.i = (__u16)va_arg(args, int);
375			put_unaligned((__u16)arg.i, (__u16 *)(buf+n)); n+=2;
376			break;
377		case 'i':  /* 32 bits unsigned integer */
378			arg.i = va_arg(args, __u32);
379			put_unaligned(arg.i, (__u32 *)(buf+n)); n+=4;
380			break;
381#if 0
382		case 'c': /* \0 terminated string */
383			arg.c = va_arg(args, char *);
384			strcpy(buf+n, arg.c);
385			n += strlen(arg.c) + 1;
386			break;
387#endif
388		default:
389			va_end(args);
390			return -1;
391		}
392	}
393	va_end(args);
394
395	return 0;
396}
397EXPORT_SYMBOL(irda_param_pack);
398
399/*
400 * Function irda_param_unpack (skb, fmt, ...)
401 */
402static int irda_param_unpack(__u8 *buf, char *fmt, ...)
403{
404	irda_pv_t arg;
405	va_list args;
406	char *p;
407	int n = 0;
408
409	va_start(args, fmt);
410
411	for (p = fmt; *p != '\0'; p++) {
412		switch (*p) {
413		case 'b':  /* 8 bits byte */
414			arg.ip = va_arg(args, __u32 *);
415			*arg.ip = buf[n++];
416			break;
417		case 's':  /* 16 bits short */
418			arg.ip = va_arg(args, __u32 *);
419			*arg.ip = get_unaligned((__u16 *)(buf+n)); n+=2;
420			break;
421		case 'i':  /* 32 bits unsigned integer */
422			arg.ip = va_arg(args, __u32 *);
423			*arg.ip = get_unaligned((__u32 *)(buf+n)); n+=4;
424			break;
425#if 0
426		case 'c':   /* \0 terminated string */
427			arg.c = va_arg(args, char *);
428			strcpy(arg.c, buf+n);
429			n += strlen(arg.c) + 1;
430			break;
431#endif
432		default:
433			va_end(args);
434			return -1;
435		}
436
437	}
438	va_end(args);
439
440	return 0;
441}
442
443/*
444 * Function irda_param_insert (self, pi, buf, len, info)
445 *
446 *    Insert the specified parameter (pi) into buffer. Returns number of
447 *    bytes inserted
448 */
449int irda_param_insert(void *self, __u8 pi, __u8 *buf, int len,
450		      pi_param_info_t *info)
451{
452	const pi_minor_info_t *pi_minor_info;
453	__u8 pi_minor;
454	__u8 pi_major;
455	int type;
456	int ret = -1;
457	int n = 0;
458
459	IRDA_ASSERT(buf != NULL, return ret;);
460	IRDA_ASSERT(info != NULL, return ret;);
461
462	pi_minor = pi & info->pi_mask;
463	pi_major = pi >> info->pi_major_offset;
464
465	/* Check if the identifier value (pi) is valid */
466	if ((pi_major > info->len-1) ||
467	    (pi_minor > info->tables[pi_major].len-1))
468	{
469		pr_debug("%s(), no handler for parameter=0x%02x\n",
470			 __func__, pi);
471
472		/* Skip this parameter */
473		return -1;
474	}
475
476	/* Lookup the info on how to parse this parameter */
477	pi_minor_info = &info->tables[pi_major].pi_minor_call_table[pi_minor];
478
479	/* Find expected data type for this parameter identifier (pi)*/
480	type = pi_minor_info->type;
481
482	/*  Check if handler has been implemented */
483	if (!pi_minor_info->func) {
484		net_info_ratelimited("%s: no handler for pi=%#x\n",
485				     __func__, pi);
486		/* Skip this parameter */
487		return -1;
488	}
489
490	/* Insert parameter value */
491	ret = (*pv_insert_table[type & PV_MASK])(self, buf+n, len, pi, type,
492						 pi_minor_info->func);
493	return ret;
494}
495EXPORT_SYMBOL(irda_param_insert);
496
497/*
498 * Function irda_param_extract (self, buf, len, info)
499 *
500 *    Parse all parameters. If len is correct, then everything should be
501 *    safe. Returns the number of bytes that was parsed
502 *
503 */
504static int irda_param_extract(void *self, __u8 *buf, int len,
505			      pi_param_info_t *info)
506{
507	const pi_minor_info_t *pi_minor_info;
508	__u8 pi_minor;
509	__u8 pi_major;
510	int type;
511	int ret = -1;
512	int n = 0;
513
514	IRDA_ASSERT(buf != NULL, return ret;);
515	IRDA_ASSERT(info != NULL, return ret;);
516
517	pi_minor = buf[n] & info->pi_mask;
518	pi_major = buf[n] >> info->pi_major_offset;
519
520	/* Check if the identifier value (pi) is valid */
521	if ((pi_major > info->len-1) ||
522	    (pi_minor > info->tables[pi_major].len-1))
523	{
524		pr_debug("%s(), no handler for parameter=0x%02x\n",
525			 __func__, buf[0]);
526
527		/* Skip this parameter */
528		return 2 + buf[n + 1];  /* Continue */
529	}
530
531	/* Lookup the info on how to parse this parameter */
532	pi_minor_info = &info->tables[pi_major].pi_minor_call_table[pi_minor];
533
534	/* Find expected data type for this parameter identifier (pi)*/
535	type = pi_minor_info->type;
536
537	pr_debug("%s(), pi=[%d,%d], type=%d\n", __func__,
538		 pi_major, pi_minor, type);
539
540	/*  Check if handler has been implemented */
541	if (!pi_minor_info->func) {
542		net_info_ratelimited("%s: no handler for pi=%#x\n",
543				     __func__, buf[n]);
544		/* Skip this parameter */
545		return 2 + buf[n + 1]; /* Continue */
546	}
547
548	/* Parse parameter value */
549	ret = (*pv_extract_table[type & PV_MASK])(self, buf+n, len, buf[n],
550						  type, pi_minor_info->func);
551	return ret;
552}
553
554/*
555 * Function irda_param_extract_all (self, buf, len, info)
556 *
557 *    Parse all parameters. If len is correct, then everything should be
558 *    safe. Returns the number of bytes that was parsed
559 *
560 */
561int irda_param_extract_all(void *self, __u8 *buf, int len,
562			   pi_param_info_t *info)
563{
564	int ret = -1;
565	int n = 0;
566
567	IRDA_ASSERT(buf != NULL, return ret;);
568	IRDA_ASSERT(info != NULL, return ret;);
569
570	/*
571	 * Parse all parameters. Each parameter must be at least two bytes
572	 * long or else there is no point in trying to parse it
573	 */
574	while (len > 2) {
575		ret = irda_param_extract(self, buf+n, len, info);
576		if (ret < 0)
577			return ret;
578
579		n += ret;
580		len -= ret;
581	}
582	return n;
583}
584EXPORT_SYMBOL(irda_param_extract_all);