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Diffstat (limited to 'net/irda/parameters.c')
| -rw-r--r-- | net/irda/parameters.c | 589 |
1 files changed, 589 insertions, 0 deletions
diff --git a/net/irda/parameters.c b/net/irda/parameters.c new file mode 100644 index 00000000000..1324942f976 --- /dev/null +++ b/net/irda/parameters.c @@ -0,0 +1,589 @@ +/********************************************************************* + * + * 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, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + * + ********************************************************************/ + +#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 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 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 lenght 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 lenght 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) { + IRDA_DEBUG(2, "%s(), using 1 byte\n", __FUNCTION__); + p.pl = 1; + } else if (p.pv.i < 0xffff) { + IRDA_DEBUG(2, "%s(), using 2 bytes\n", __FUNCTION__); + p.pl = 2; + } else { + IRDA_DEBUG(2, "%s(), using 4 bytes\n", __FUNCTION__); + p.pl = 4; /* Default length */ + } + } + /* Check if buffer is long enough for insertion */ + if (len < (2+p.pl)) { + IRDA_WARNING("%s: buffer to short for insertion!\n", + __FUNCTION__); + return -1; + } + IRDA_DEBUG(2, "%s(), pi=%#x, pl=%d, pi=%d\n", __FUNCTION__, + 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: + IRDA_WARNING("%s: length %d not supported\n", + __FUNCTION__, 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 lenght we extract */ + int err; + + p.pi = pi; /* In case handler needs to know */ + p.pl = buf[1]; /* Extract lenght 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)) { + IRDA_WARNING("%s: buffer to short for parsing! " + "Need %d bytes, but len is only %d\n", + __FUNCTION__, 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)) { + IRDA_ERROR("%s: invalid parameter length! " + "Expected %d bytes, but value had %d bytes!\n", + __FUNCTION__, 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: + IRDA_WARNING("%s: length %d not supported\n", + __FUNCTION__, p.pl); + + /* Skip parameter */ + return p.pl+2; + } + + IRDA_DEBUG(2, "%s(), pi=%#x, pl=%d, pi=%d\n", __FUNCTION__, + 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; + + IRDA_DEBUG(2, "%s()\n", __FUNCTION__); + + p.pi = pi; /* In case handler needs to know */ + p.pl = buf[1]; /* Extract lenght of value */ + + IRDA_DEBUG(2, "%s(), pi=%#x, pl=%d\n", __FUNCTION__, + p.pi, p.pl); + + /* Check if buffer is long enough for parsing */ + if (len < (2+p.pl)) { + IRDA_WARNING("%s: buffer to short for parsing! " + "Need %d bytes, but len is only %d\n", + __FUNCTION__, 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); + + IRDA_DEBUG(2, "%s(), str=0x%02x 0x%02x\n", __FUNCTION__, + (__u8) str[0], (__u8) str[1]); + + /* Null terminate string */ + str[p.pl+1] = '\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 lenght of value */ + + /* Check if buffer is long enough for parsing */ + if (len < (2+p.pl)) { + IRDA_WARNING("%s: buffer to short for parsing! " + "Need %d bytes, but len is only %d\n", + __FUNCTION__, p.pl, len); + return -1; + } + + IRDA_DEBUG(0, "%s(), not impl\n", __FUNCTION__); + + 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) +{ + 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 != 0, 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)) + { + IRDA_DEBUG(0, "%s(), no handler for parameter=0x%02x\n", + __FUNCTION__, 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) { + IRDA_MESSAGE("%s: no handler for pi=%#x\n", __FUNCTION__, 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) +{ + 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 != 0, 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)) + { + IRDA_DEBUG(0, "%s(), no handler for parameter=0x%02x\n", + __FUNCTION__, 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; + + IRDA_DEBUG(3, "%s(), pi=[%d,%d], type=%d\n", __FUNCTION__, + pi_major, pi_minor, type); + + /* Check if handler has been implemented */ + if (!pi_minor_info->func) { + IRDA_MESSAGE("%s: no handler for pi=%#x\n", + __FUNCTION__, 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 != 0, 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); |