File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/net/irda/parameters.c b/net/irda/parameters.c
new file mode 100644
index 0000000..16ce32f
--- /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);