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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /net/irda/parameters.c
Initial import
Diffstat (limited to 'net/irda/parameters.c')
-rw-r--r--net/irda/parameters.c584
1 files changed, 584 insertions, 0 deletions
diff --git a/net/irda/parameters.c b/net/irda/parameters.c
new file mode 100644
index 000000000..16ce32ffe
--- /dev/null
+++ b/net/irda/parameters.c
@@ -0,0 +1,584 @@
+/*********************************************************************
+ *
+ * Filename: parameters.c
+ * Version: 1.0
+ * Description: A more general way to handle (pi,pl,pv) parameters
+ * Status: Experimental.
+ * Author: Dag Brattli <dagb@cs.uit.no>
+ * Created at: Mon Jun 7 10:25:11 1999
+ * Modified at: Sun Jan 30 14:08:39 2000
+ * Modified by: Dag Brattli <dagb@cs.uit.no>
+ *
+ * Copyright (c) 1999-2000 Dag Brattli, All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ *
+ ********************************************************************/
+
+#include <linux/types.h>
+#include <linux/module.h>
+
+#include <asm/unaligned.h>
+#include <asm/byteorder.h>
+
+#include <net/irda/irda.h>
+#include <net/irda/parameters.h>
+
+static int irda_extract_integer(void *self, __u8 *buf, int len, __u8 pi,
+ PV_TYPE type, PI_HANDLER func);
+static int irda_extract_string(void *self, __u8 *buf, int len, __u8 pi,
+ PV_TYPE type, PI_HANDLER func);
+static int irda_extract_octseq(void *self, __u8 *buf, int len, __u8 pi,
+ PV_TYPE type, PI_HANDLER func);
+static int irda_extract_no_value(void *self, __u8 *buf, int len, __u8 pi,
+ PV_TYPE type, PI_HANDLER func);
+
+static int irda_insert_integer(void *self, __u8 *buf, int len, __u8 pi,
+ PV_TYPE type, PI_HANDLER func);
+static int irda_insert_no_value(void *self, __u8 *buf, int len, __u8 pi,
+ PV_TYPE type, PI_HANDLER func);
+
+static int irda_param_unpack(__u8 *buf, char *fmt, ...);
+
+/* Parameter value call table. Must match PV_TYPE */
+static const PV_HANDLER pv_extract_table[] = {
+ irda_extract_integer, /* Handler for any length integers */
+ irda_extract_integer, /* Handler for 8 bits integers */
+ irda_extract_integer, /* Handler for 16 bits integers */
+ irda_extract_string, /* Handler for strings */
+ irda_extract_integer, /* Handler for 32 bits integers */
+ irda_extract_octseq, /* Handler for octet sequences */
+ irda_extract_no_value /* Handler for no value parameters */
+};
+
+static const PV_HANDLER pv_insert_table[] = {
+ irda_insert_integer, /* Handler for any length integers */
+ irda_insert_integer, /* Handler for 8 bits integers */
+ irda_insert_integer, /* Handler for 16 bits integers */
+ NULL, /* Handler for strings */
+ irda_insert_integer, /* Handler for 32 bits integers */
+ NULL, /* Handler for octet sequences */
+ irda_insert_no_value /* Handler for no value parameters */
+};
+
+/*
+ * Function irda_insert_no_value (self, buf, len, pi, type, func)
+ */
+static int irda_insert_no_value(void *self, __u8 *buf, int len, __u8 pi,
+ PV_TYPE type, PI_HANDLER func)
+{
+ irda_param_t p;
+ int ret;
+
+ p.pi = pi;
+ p.pl = 0;
+
+ /* Call handler for this parameter */
+ ret = (*func)(self, &p, PV_GET);
+
+ /* Extract values anyway, since handler may need them */
+ irda_param_pack(buf, "bb", p.pi, p.pl);
+
+ if (ret < 0)
+ return ret;
+
+ return 2; /* Inserted pl+2 bytes */
+}
+
+/*
+ * Function irda_extract_no_value (self, buf, len, type, func)
+ *
+ * Extracts a parameter without a pv field (pl=0)
+ *
+ */
+static int irda_extract_no_value(void *self, __u8 *buf, int len, __u8 pi,
+ PV_TYPE type, PI_HANDLER func)
+{
+ irda_param_t p;
+ int ret;
+
+ /* Extract values anyway, since handler may need them */
+ irda_param_unpack(buf, "bb", &p.pi, &p.pl);
+
+ /* Call handler for this parameter */
+ ret = (*func)(self, &p, PV_PUT);
+
+ if (ret < 0)
+ return ret;
+
+ return 2; /* Extracted pl+2 bytes */
+}
+
+/*
+ * Function irda_insert_integer (self, buf, len, pi, type, func)
+ */
+static int irda_insert_integer(void *self, __u8 *buf, int len, __u8 pi,
+ PV_TYPE type, PI_HANDLER func)
+{
+ irda_param_t p;
+ int n = 0;
+ int err;
+
+ p.pi = pi; /* In case handler needs to know */
+ p.pl = type & PV_MASK; /* The integer type codes the length as well */
+ p.pv.i = 0; /* Clear value */
+
+ /* Call handler for this parameter */
+ err = (*func)(self, &p, PV_GET);
+ if (err < 0)
+ return err;
+
+ /*
+ * If parameter length is still 0, then (1) this is an any length
+ * integer, and (2) the handler function does not care which length
+ * we choose to use, so we pick the one the gives the fewest bytes.
+ */
+ if (p.pl == 0) {
+ if (p.pv.i < 0xff) {
+ pr_debug("%s(), using 1 byte\n", __func__);
+ p.pl = 1;
+ } else if (p.pv.i < 0xffff) {
+ pr_debug("%s(), using 2 bytes\n", __func__);
+ p.pl = 2;
+ } else {
+ pr_debug("%s(), using 4 bytes\n", __func__);
+ p.pl = 4; /* Default length */
+ }
+ }
+ /* Check if buffer is long enough for insertion */
+ if (len < (2+p.pl)) {
+ net_warn_ratelimited("%s: buffer too short for insertion!\n",
+ __func__);
+ return -1;
+ }
+ pr_debug("%s(), pi=%#x, pl=%d, pi=%d\n", __func__,
+ p.pi, p.pl, p.pv.i);
+ switch (p.pl) {
+ case 1:
+ n += irda_param_pack(buf, "bbb", p.pi, p.pl, (__u8) p.pv.i);
+ break;
+ case 2:
+ if (type & PV_BIG_ENDIAN)
+ p.pv.i = cpu_to_be16((__u16) p.pv.i);
+ else
+ p.pv.i = cpu_to_le16((__u16) p.pv.i);
+ n += irda_param_pack(buf, "bbs", p.pi, p.pl, (__u16) p.pv.i);
+ break;
+ case 4:
+ if (type & PV_BIG_ENDIAN)
+ cpu_to_be32s(&p.pv.i);
+ else
+ cpu_to_le32s(&p.pv.i);
+ n += irda_param_pack(buf, "bbi", p.pi, p.pl, p.pv.i);
+
+ break;
+ default:
+ net_warn_ratelimited("%s: length %d not supported\n",
+ __func__, p.pl);
+ /* Skip parameter */
+ return -1;
+ }
+
+ return p.pl+2; /* Inserted pl+2 bytes */
+}
+
+/*
+ * Function irda_extract integer (self, buf, len, pi, type, func)
+ *
+ * Extract a possibly variable length integer from buffer, and call
+ * handler for processing of the parameter
+ */
+static int irda_extract_integer(void *self, __u8 *buf, int len, __u8 pi,
+ PV_TYPE type, PI_HANDLER func)
+{
+ irda_param_t p;
+ int n = 0;
+ int extract_len; /* Real length we extract */
+ int err;
+
+ p.pi = pi; /* In case handler needs to know */
+ p.pl = buf[1]; /* Extract length of value */
+ p.pv.i = 0; /* Clear value */
+ extract_len = p.pl; /* Default : extract all */
+
+ /* Check if buffer is long enough for parsing */
+ if (len < (2+p.pl)) {
+ net_warn_ratelimited("%s: buffer too short for parsing! Need %d bytes, but len is only %d\n",
+ __func__, p.pl, len);
+ return -1;
+ }
+
+ /*
+ * Check that the integer length is what we expect it to be. If the
+ * handler want a 16 bits integer then a 32 bits is not good enough
+ * PV_INTEGER means that the handler is flexible.
+ */
+ if (((type & PV_MASK) != PV_INTEGER) && ((type & PV_MASK) != p.pl)) {
+ net_err_ratelimited("%s: invalid parameter length! Expected %d bytes, but value had %d bytes!\n",
+ __func__, type & PV_MASK, p.pl);
+
+ /* Most parameters are bit/byte fields or little endian,
+ * so it's ok to only extract a subset of it (the subset
+ * that the handler expect). This is necessary, as some
+ * broken implementations seems to add extra undefined bits.
+ * If the parameter is shorter than we expect or is big
+ * endian, we can't play those tricks. Jean II */
+ if((p.pl < (type & PV_MASK)) || (type & PV_BIG_ENDIAN)) {
+ /* Skip parameter */
+ return p.pl+2;
+ } else {
+ /* Extract subset of it, fallthrough */
+ extract_len = type & PV_MASK;
+ }
+ }
+
+
+ switch (extract_len) {
+ case 1:
+ n += irda_param_unpack(buf+2, "b", &p.pv.i);
+ break;
+ case 2:
+ n += irda_param_unpack(buf+2, "s", &p.pv.i);
+ if (type & PV_BIG_ENDIAN)
+ p.pv.i = be16_to_cpu((__u16) p.pv.i);
+ else
+ p.pv.i = le16_to_cpu((__u16) p.pv.i);
+ break;
+ case 4:
+ n += irda_param_unpack(buf+2, "i", &p.pv.i);
+ if (type & PV_BIG_ENDIAN)
+ be32_to_cpus(&p.pv.i);
+ else
+ le32_to_cpus(&p.pv.i);
+ break;
+ default:
+ net_warn_ratelimited("%s: length %d not supported\n",
+ __func__, p.pl);
+
+ /* Skip parameter */
+ return p.pl+2;
+ }
+
+ pr_debug("%s(), pi=%#x, pl=%d, pi=%d\n", __func__,
+ p.pi, p.pl, p.pv.i);
+ /* Call handler for this parameter */
+ err = (*func)(self, &p, PV_PUT);
+ if (err < 0)
+ return err;
+
+ return p.pl+2; /* Extracted pl+2 bytes */
+}
+
+/*
+ * Function irda_extract_string (self, buf, len, type, func)
+ */
+static int irda_extract_string(void *self, __u8 *buf, int len, __u8 pi,
+ PV_TYPE type, PI_HANDLER func)
+{
+ char str[33];
+ irda_param_t p;
+ int err;
+
+ p.pi = pi; /* In case handler needs to know */
+ p.pl = buf[1]; /* Extract length of value */
+ if (p.pl > 32)
+ p.pl = 32;
+
+ pr_debug("%s(), pi=%#x, pl=%d\n", __func__,
+ p.pi, p.pl);
+
+ /* Check if buffer is long enough for parsing */
+ if (len < (2+p.pl)) {
+ net_warn_ratelimited("%s: buffer too short for parsing! Need %d bytes, but len is only %d\n",
+ __func__, p.pl, len);
+ return -1;
+ }
+
+ /* Should be safe to copy string like this since we have already
+ * checked that the buffer is long enough */
+ strncpy(str, buf+2, p.pl);
+
+ pr_debug("%s(), str=0x%02x 0x%02x\n",
+ __func__, (__u8)str[0], (__u8)str[1]);
+
+ /* Null terminate string */
+ str[p.pl] = '\0';
+
+ p.pv.c = str; /* Handler will need to take a copy */
+
+ /* Call handler for this parameter */
+ err = (*func)(self, &p, PV_PUT);
+ if (err < 0)
+ return err;
+
+ return p.pl+2; /* Extracted pl+2 bytes */
+}
+
+/*
+ * Function irda_extract_octseq (self, buf, len, type, func)
+ */
+static int irda_extract_octseq(void *self, __u8 *buf, int len, __u8 pi,
+ PV_TYPE type, PI_HANDLER func)
+{
+ irda_param_t p;
+
+ p.pi = pi; /* In case handler needs to know */
+ p.pl = buf[1]; /* Extract length of value */
+
+ /* Check if buffer is long enough for parsing */
+ if (len < (2+p.pl)) {
+ net_warn_ratelimited("%s: buffer too short for parsing! Need %d bytes, but len is only %d\n",
+ __func__, p.pl, len);
+ return -1;
+ }
+
+ pr_debug("%s(), not impl\n", __func__);
+
+ return p.pl+2; /* Extracted pl+2 bytes */
+}
+
+/*
+ * Function irda_param_pack (skb, fmt, ...)
+ *
+ * Format:
+ * 'i' = 32 bits integer
+ * 's' = string
+ *
+ */
+int irda_param_pack(__u8 *buf, char *fmt, ...)
+{
+ irda_pv_t arg;
+ va_list args;
+ char *p;
+ int n = 0;
+
+ va_start(args, fmt);
+
+ for (p = fmt; *p != '\0'; p++) {
+ switch (*p) {
+ case 'b': /* 8 bits unsigned byte */
+ buf[n++] = (__u8)va_arg(args, int);
+ break;
+ case 's': /* 16 bits unsigned short */
+ arg.i = (__u16)va_arg(args, int);
+ put_unaligned((__u16)arg.i, (__u16 *)(buf+n)); n+=2;
+ break;
+ case 'i': /* 32 bits unsigned integer */
+ arg.i = va_arg(args, __u32);
+ put_unaligned(arg.i, (__u32 *)(buf+n)); n+=4;
+ break;
+#if 0
+ case 'c': /* \0 terminated string */
+ arg.c = va_arg(args, char *);
+ strcpy(buf+n, arg.c);
+ n += strlen(arg.c) + 1;
+ break;
+#endif
+ default:
+ va_end(args);
+ return -1;
+ }
+ }
+ va_end(args);
+
+ return 0;
+}
+EXPORT_SYMBOL(irda_param_pack);
+
+/*
+ * Function irda_param_unpack (skb, fmt, ...)
+ */
+static int irda_param_unpack(__u8 *buf, char *fmt, ...)
+{
+ irda_pv_t arg;
+ va_list args;
+ char *p;
+ int n = 0;
+
+ va_start(args, fmt);
+
+ for (p = fmt; *p != '\0'; p++) {
+ switch (*p) {
+ case 'b': /* 8 bits byte */
+ arg.ip = va_arg(args, __u32 *);
+ *arg.ip = buf[n++];
+ break;
+ case 's': /* 16 bits short */
+ arg.ip = va_arg(args, __u32 *);
+ *arg.ip = get_unaligned((__u16 *)(buf+n)); n+=2;
+ break;
+ case 'i': /* 32 bits unsigned integer */
+ arg.ip = va_arg(args, __u32 *);
+ *arg.ip = get_unaligned((__u32 *)(buf+n)); n+=4;
+ break;
+#if 0
+ case 'c': /* \0 terminated string */
+ arg.c = va_arg(args, char *);
+ strcpy(arg.c, buf+n);
+ n += strlen(arg.c) + 1;
+ break;
+#endif
+ default:
+ va_end(args);
+ return -1;
+ }
+
+ }
+ va_end(args);
+
+ return 0;
+}
+
+/*
+ * Function irda_param_insert (self, pi, buf, len, info)
+ *
+ * Insert the specified parameter (pi) into buffer. Returns number of
+ * bytes inserted
+ */
+int irda_param_insert(void *self, __u8 pi, __u8 *buf, int len,
+ pi_param_info_t *info)
+{
+ const pi_minor_info_t *pi_minor_info;
+ __u8 pi_minor;
+ __u8 pi_major;
+ int type;
+ int ret = -1;
+ int n = 0;
+
+ IRDA_ASSERT(buf != NULL, return ret;);
+ IRDA_ASSERT(info != NULL, return ret;);
+
+ pi_minor = pi & info->pi_mask;
+ pi_major = pi >> info->pi_major_offset;
+
+ /* Check if the identifier value (pi) is valid */
+ if ((pi_major > info->len-1) ||
+ (pi_minor > info->tables[pi_major].len-1))
+ {
+ pr_debug("%s(), no handler for parameter=0x%02x\n",
+ __func__, pi);
+
+ /* Skip this parameter */
+ return -1;
+ }
+
+ /* Lookup the info on how to parse this parameter */
+ pi_minor_info = &info->tables[pi_major].pi_minor_call_table[pi_minor];
+
+ /* Find expected data type for this parameter identifier (pi)*/
+ type = pi_minor_info->type;
+
+ /* Check if handler has been implemented */
+ if (!pi_minor_info->func) {
+ net_info_ratelimited("%s: no handler for pi=%#x\n",
+ __func__, pi);
+ /* Skip this parameter */
+ return -1;
+ }
+
+ /* Insert parameter value */
+ ret = (*pv_insert_table[type & PV_MASK])(self, buf+n, len, pi, type,
+ pi_minor_info->func);
+ return ret;
+}
+EXPORT_SYMBOL(irda_param_insert);
+
+/*
+ * Function irda_param_extract (self, buf, len, info)
+ *
+ * Parse all parameters. If len is correct, then everything should be
+ * safe. Returns the number of bytes that was parsed
+ *
+ */
+static int irda_param_extract(void *self, __u8 *buf, int len,
+ pi_param_info_t *info)
+{
+ const pi_minor_info_t *pi_minor_info;
+ __u8 pi_minor;
+ __u8 pi_major;
+ int type;
+ int ret = -1;
+ int n = 0;
+
+ IRDA_ASSERT(buf != NULL, return ret;);
+ IRDA_ASSERT(info != NULL, return ret;);
+
+ pi_minor = buf[n] & info->pi_mask;
+ pi_major = buf[n] >> info->pi_major_offset;
+
+ /* Check if the identifier value (pi) is valid */
+ if ((pi_major > info->len-1) ||
+ (pi_minor > info->tables[pi_major].len-1))
+ {
+ pr_debug("%s(), no handler for parameter=0x%02x\n",
+ __func__, buf[0]);
+
+ /* Skip this parameter */
+ return 2 + buf[n + 1]; /* Continue */
+ }
+
+ /* Lookup the info on how to parse this parameter */
+ pi_minor_info = &info->tables[pi_major].pi_minor_call_table[pi_minor];
+
+ /* Find expected data type for this parameter identifier (pi)*/
+ type = pi_minor_info->type;
+
+ pr_debug("%s(), pi=[%d,%d], type=%d\n", __func__,
+ pi_major, pi_minor, type);
+
+ /* Check if handler has been implemented */
+ if (!pi_minor_info->func) {
+ net_info_ratelimited("%s: no handler for pi=%#x\n",
+ __func__, buf[n]);
+ /* Skip this parameter */
+ return 2 + buf[n + 1]; /* Continue */
+ }
+
+ /* Parse parameter value */
+ ret = (*pv_extract_table[type & PV_MASK])(self, buf+n, len, buf[n],
+ type, pi_minor_info->func);
+ return ret;
+}
+
+/*
+ * Function irda_param_extract_all (self, buf, len, info)
+ *
+ * Parse all parameters. If len is correct, then everything should be
+ * safe. Returns the number of bytes that was parsed
+ *
+ */
+int irda_param_extract_all(void *self, __u8 *buf, int len,
+ pi_param_info_t *info)
+{
+ int ret = -1;
+ int n = 0;
+
+ IRDA_ASSERT(buf != NULL, return ret;);
+ IRDA_ASSERT(info != NULL, return ret;);
+
+ /*
+ * Parse all parameters. Each parameter must be at least two bytes
+ * long or else there is no point in trying to parse it
+ */
+ while (len > 2) {
+ ret = irda_param_extract(self, buf+n, len, info);
+ if (ret < 0)
+ return ret;
+
+ n += ret;
+ len -= ret;
+ }
+ return n;
+}
+EXPORT_SYMBOL(irda_param_extract_all);