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Merged in antmerlino/apps/i8shark_fcs_suppresion (pull request #194)

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i8shark: Adds support for intentionally suppressing passing the FCS so that Wireshark doesn't try to validate it.

Approved-by: Gregory Nutt <gnutt@nuttx.org>
This commit is contained in:
Anthony Merlino 2019-08-10 18:26:33 +00:00 committed by Gregory Nutt
parent 6228b43a72
commit c68dd23509
2 changed files with 62 additions and 33 deletions
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19
wireless/ieee802154/i8shark/Kconfig
View File

@ -12,6 +12,14 @@ config IEEE802154_I8SHARK
if IEEE802154_I8SHARK
config IEEE802154_I8SHARK_DAEMON_PRIORITY
int "i8shark task priority"
default 100
config IEEE802154_I8SHARK_DAEMON_STACKSIZE
int "i8shark stack size"
default 2048
config IEEE802154_I8SHARK_DEVPATH
string "MAC char driver path"
default "/dev/ieee0"
@ -22,6 +30,17 @@ config IEEE802154_I8SHARK_HOST_IPADDR
hex "Host IP address where Wireshark is running"
default 0x0a000001
config IEEE802154_I8SHARK_SUPPRESS_FCS
bool "Suppress passing FCS to Wireshark"
default n
---help---
The current Wireshark disector does not continue processing a frame, aka
6LoWPAN processing, if the FCS is incorrect. Furthermore, the FCS length
in the disector is hard-coded to be 2 bytes. Some PHY implement different
length FCS. However, Wireshark will ignore the FCS checking if an FCS is
not provided. This option intentionally excludes the last n bytes of the
frame where n is the FCS length of the current radio settings.
config IEEE802154_I8SHARK_XBEE_APPHDR
bool "XBee App Header compensation"
default n

76
wireless/ieee802154/i8shark/i8shark_main.c
View File

@ -104,7 +104,6 @@ struct i8shark_state_s
/* User exposed settings */
uint8_t chan;
FAR char devpath[I8SHARK_MAX_DEVPATH];
};
@ -229,7 +228,6 @@ static int i8shark_init(FAR struct i8shark_state_s *i8shark)
/* Set the default settings using config options */
i8shark->chan = CONFIG_IEEE802154_I8SHARK_CHANNEL;
strcpy(i8shark->devpath, CONFIG_IEEE802154_I8SHARK_DEVPATH);
/* Flags for synchronzing with daemon state */
@ -323,7 +321,7 @@ static int i8shark_daemon(int argc, FAR char *argv[])
enum ieee802154_frametype_e ftype;
uint8_t zepframe[I8SHARK_MAX_ZEPFRAME];
clock_t systime;
int ind = 0;
int i = 0;
int nbytes;
/* Get an incoming frame from the MAC character driver */
@ -336,12 +334,12 @@ static int i8shark_daemon(int argc, FAR char *argv[])
/* First 2 bytes of packet represent preamble. For ZEP, "EX" */
zepframe[ind++] = 'E';
zepframe[ind++] = 'X';
zepframe[i++] = 'E';
zepframe[i++] = 'X';
/* The next byte is the version. We are using V2 */
zepframe[ind++] = 2;
zepframe[i++] = 2;
/* Next byte is type. ZEP only differentiates between ACK and Data. My
* assumption is that Data also includes MAC command frames and beacon
@ -353,27 +351,27 @@ static int i8shark_daemon(int argc, FAR char *argv[])
if (ftype == IEEE802154_FRAME_ACK)
{
zepframe[ind++] = 2;
zepframe[i++] = 2;
/* Not sure why, but the ZEP header allows for a 4-byte sequence no.
* despite 802.15.4 sequence number only being 1-byte
*/
zepframe[ind] = frame.meta.dsn;
ind += 4;
zepframe[i] = frame.meta.dsn;
i += 4;
}
else
{
zepframe[ind++] = 1;
zepframe[i++] = 1;
/* Next bytes is the Channel ID */
ieee802154_getchan(fd, &zepframe[ind++]);
ieee802154_getchan(fd, &zepframe[i++]);
/* For now, just hard code the device ID to an arbitrary value */
zepframe[ind++] = 0xFA;
zepframe[ind++] = 0xDE;
zepframe[i++] = 0xFA;
zepframe[i++] = 0xDE;
/* Not completely sure what LQI mode is. My best guess as of now based
* on a few comments in the Wireshark code is that it determines whether
@ -383,46 +381,46 @@ static int i8shark_daemon(int argc, FAR char *argv[])
* may be a bad assumption for certain radios.
*/
zepframe[ind++] = 1;
zepframe[i++] = 1;
/* Next byte is the LQI value */
zepframe[ind++] = frame.meta.lqi;
zepframe[i++] = frame.meta.lqi;
/* Need to use NTP to get time, but for now, include the system time */
systime = clock();
memcpy(&zepframe[ind], &systime, 8);
ind += 8;
memcpy(&zepframe[i], &systime, 8);
i += 8;
/* Not sure why, but the ZEP header allows for a 4-byte sequence no.
* despite 802.15.4 sequence number only being 1-byte
*/
zepframe[ind] = frame.meta.dsn;
zepframe[ind+1] = 0;
zepframe[ind+2] = 0;
zepframe[ind+3] = 0;
ind += 4;
zepframe[i] = frame.meta.dsn;
zepframe[i+1] = 0;
zepframe[i+2] = 0;
zepframe[i+3] = 0;
i += 4;
/* Skip 10-bytes for reserved fields */
ind += 10;
i += 10;
/* Last byte is the length */
#ifdef CONFIG_IEEE802154_I8SHARK_XBEE_APPHDR
zepframe[ind++] = frame.length - 2;
zepframe[i++] = frame.length - 2;
#else
zepframe[ind++] = frame.length;
zepframe[i++] = frame.length;
#endif
}
/* The ZEP header is filled, now copy the frame in */
#ifdef CONFIG_IEEE802154_I8SHARK_XBEE_APPHDR
memcpy(&zepframe[ind], frame.payload, frame.offset);
ind += frame.offset;
memcpy(&zepframe[i], frame.payload, frame.offset);
i += frame.offset;
/* XBee radios use a 2 byte "application header" to support duplicate packet
* detection. Wireshark doesn't know how to handle this data, so we provide
@ -436,18 +434,30 @@ static int i8shark_daemon(int argc, FAR char *argv[])
* will not fail.
*/
memcpy(&zepframe[ind], (frame.payload + frame.offset + 2),
memcpy(&zepframe[i], (frame.payload + frame.offset + 2),
(frame.length - frame.offset - 2));
ind += frame.length - frame.offset - 4;
i += frame.length - frame.offset - 4;
#else
memcpy(&zepframe[ind], frame.payload, frame.length);
ind += frame.length;
/* If FCS suppression is enabled, subtract the FCS length to reduce the
* piece of the frame copied.
*/
#ifdef CONFIG_IEEE802154_I8SHARK_SUPPRESS_FCS
{
uint8_t fcslen;
ieee802154_getfcslen(fd, &fcslen);
frame.length -= fcslen;
}
#endif
memcpy(&zepframe[i], frame.payload, frame.length);
i += frame.length;
#endif
/* Send the encapsulated frame to Wireshark over UDP */
nbytes = sendto(sockfd, zepframe, ind, 0, (struct sockaddr*)&raddr, addrlen);
if (nbytes < ind)
nbytes = sendto(sockfd, zepframe, i, 0, (struct sockaddr*)&raddr, addrlen);
if (nbytes < i)
{
fprintf(stderr, "ERROR: sendto() did not send all bytes. %d\n", errno);
}