Adds an initial implementation for RFCOMM in Bluetooth monitor.
Implementation for Decoding MSC, RPN, RLS, PN, NSC frames
will be covered in the next patch-set.
*v1: Incorporated Johan comments.
Gowtham Anandha Babu (4):
monitor/rfcomm: Add RFCOMM support to btmon
monitor/rfcomm: Add support for printing RFCOMM hdr
monitor/rfcomm: Add support for UIH frame decoding
monitor/rfcomm: Add support for mcc frame decoding
Makefile.tools | 1 +
android/Android.mk | 1 +
monitor/l2cap.c | 4 +
monitor/l2cap.h | 1 +
monitor/rfcomm.c | 275 +++++++++++++++++++++++++++++++++++++++++++++++++++++
5 files changed, 282 insertions(+)
create mode 100644 monitor/rfcomm.c
--
1.9.1
Hi Luiz,
> -----Original Message-----
> From: [email protected] [mailto:linux-bluetooth-
> [email protected]] On Behalf Of Gowtham Anandha Babu
> Sent: Friday, November 07, 2014 8:27 PM
> To: 'Luiz Augusto von Dentz'
> Cc: [email protected]; 'Dmitry Kasatkin'; 'Bharat Panda';
> [email protected]
> Subject: RE: [PATCH v1 2/4] monitor/rfcomm: Add support for printing
> RFCOMM hdr
>
> Hi Luiz,
>
> > -----Original Message-----
> > From: Luiz Augusto von Dentz [mailto:[email protected]]
> > Sent: Friday, November 07, 2014 7:57 PM
> > To: Gowtham Anandha Babu
> > Cc: [email protected]; Dmitry Kasatkin; Bharat Panda;
> > [email protected]
> > Subject: Re: [PATCH v1 2/4] monitor/rfcomm: Add support for printing
> > RFCOMM hdr
> >
> > Hi Gowtham,
> >
> > On Fri, Nov 7, 2014 at 3:06 PM, Gowtham Anandha Babu
> > <[email protected]> wrote:
> > > Changes made to decode RFCOMM hdr and print the same.
> > >
> > > RFCOMM: Unnumbered Info with Header Check (UIH)(0xef)
> > > Address: 0x01 cr 0 dlci 0x00
> > > Control: 0xef poll/final 0
> > > Length: 10
> > > FCS: 0xaa
> > > 81 11 20 e0 27 00 9a 02 00 07 aa .. .'......
> > >
> > > ---
> > > monitor/rfcomm.c | 50
> > > +++++++++++++++++++++++++++++++++++++++++++++++---
> > > 1 file changed, 47 insertions(+), 3 deletions(-)
> > >
> > > diff --git a/monitor/rfcomm.c b/monitor/rfcomm.c index
> > > 155bde2..a70c404 100644
> > > --- a/monitor/rfcomm.c
> > > +++ b/monitor/rfcomm.c
> > > @@ -44,6 +44,11 @@
> > > #include "sdp.h"
> > > #include "rfcomm.h"
> > >
> > > +#define GET_LEN8(length) ((length & 0xfe) >> 1) #define
> > > +GET_LEN16(length) ((length & 0xfffe) >> 1)
> > > +#define GET_CR(type) ((type & 0x02) >> 1)
> > > +#define GET_PF(ctr) (((ctr) >> 4) & 0x1)
> > > +
> > > struct rfcomm_lhdr {
> > > uint8_t address;
> > > uint8_t control;
> > > @@ -57,6 +62,24 @@ struct rfcomm_frame {
> > > struct l2cap_frame l2cap_frame; };
> > >
> > > +static void print_rfcomm_hdr(struct rfcomm_frame *rfcomm_frame,
> > > +uint8_t indent) {
> > > + struct rfcomm_lhdr hdr = rfcomm_frame->hdr;
> > > +
> > > + /* Address field */
> > > + print_field("%*cAddress: 0x%2.2x cr %d dlci 0x%2.2x", indent, ' ',
> > > + hdr.address, GET_CR(hdr.address),
> > > +
> > > + RFCOMM_GET_DLCI(hdr.address));
> > > +
> > > + /* Control field */
> > > + print_field("%*cControl: 0x%2.2x poll/final %d", indent, ' ',
> > > + hdr.control,
> > > + GET_PF(hdr.control));
> > > +
> > > + /* Length and FCS */
> > > + print_field("%*cLength: %d", indent, ' ', hdr.length);
> > > + print_field("%*cFCS: 0x%2.2x", indent, ' ', hdr.fcs); }
> > > +
> > > struct rfcomm_data {
> > > uint8_t frame;
> > > const char *str;
> > > @@ -73,12 +96,13 @@ static const struct rfcomm_data rfcomm_table[] =
> > > {
> > >
> > > void rfcomm_packet(const struct l2cap_frame *frame) {
> > > - uint8_t ctype;
> > > + uint8_t ctype, length, ex_length, indent = 1;
> > > const char *frame_str, *frame_color;
> > > struct l2cap_frame *l2cap_frame;
> > > struct rfcomm_frame rfcomm_frame;
> > > struct rfcomm_lhdr hdr;
> > > const struct rfcomm_data *rfcomm_data = NULL;
> > > + const void *ptr;
> > > int i;
> > >
> > > l2cap_frame_pull(&rfcomm_frame.l2cap_frame, frame, 0); @@
> > > -89,9 +113,24 @@ void rfcomm_packet(const struct l2cap_frame *frame)
> > > goto fail;
> > >
> > > if (!l2cap_frame_get_u8(l2cap_frame, &hdr.address) ||
> > > - !l2cap_frame_get_u8(l2cap_frame, &hdr.control))
> > > + !l2cap_frame_get_u8(l2cap_frame, &hdr.control) ||
> > > + !l2cap_frame_get_u8(l2cap_frame, &length))
> > > goto fail;
> > >
> > > + /* length maybe 1 or 2 octets */
> > > + if (RFCOMM_TEST_EA(length))
> > > + hdr.length = (uint16_t) GET_LEN8(length);
> > > + else {
> > > + if (!l2cap_frame_get_u8(l2cap_frame, &ex_length))
> > > + goto fail;
> > > + hdr.length = ((uint16_t)length << 8) | ex_length;
> > > + hdr.length = GET_LEN16(hdr.length);
> > > + }
> > > +
> > > + /* fetching FCS by frame offset */
> > > + ptr = (l2cap_frame->data)+l2cap_frame->size-1;
> > > + hdr.fcs = *(uint8_t *)(ptr);
> >
> > You should probably use l2cap_frame_pull followed by
> > l2cap_frame_get_u8 so we actually check if the frame is too short.
> > Btw, the format looks much better now.
> >
> > > /* Decoding frame type */
> > > ctype = RFCOMM_GET_TYPE(hdr.control);
> > >
> > > @@ -122,7 +161,12 @@ void rfcomm_packet(const struct l2cap_frame
> > *frame)
> > > "(0x%2.2x)", ctype);
> > >
> > > rfcomm_frame.hdr = hdr;
> > > - packet_hexdump(l2cap_frame->data, l2cap_frame->size);
> > > + print_rfcomm_hdr(&rfcomm_frame, indent);
> > > +
> > > + /* UIH frame */
> > > + if(ctype == 0xef)
> > > + packet_hexdump(l2cap_frame->data,
> > > + l2cap_frame->size);
> > > +
> > > return;
> > >
> > > fail:
> > > --
> > > 1.9.1
> > >
> > > --
> > > To unsubscribe from this list: send the line "unsubscribe
> > > linux-bluetooth" in the body of a message to
> > > [email protected] More majordomo info at
> > > http://vger.kernel.org/majordomo-info.html
> >
> >
> >
> > --
> > Luiz Augusto von Dentz
>
> I will incorporate this in v2. Is there any other changes stills needs to be
> done?
>
> Regards,
> Gowtham
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in
> the body of a message to [email protected] More majordomo
> info at http://vger.kernel.org/majordomo-info.html
I have changed FCS fetching by l2cap_frame_pull and submitted v2 for the same.
Regards,
Gowtham
Hi Luiz,
> -----Original Message-----
> From: Luiz Augusto von Dentz [mailto:[email protected]]
> Sent: Friday, November 07, 2014 7:57 PM
> To: Gowtham Anandha Babu
> Cc: [email protected]; Dmitry Kasatkin; Bharat Panda;
> [email protected]
> Subject: Re: [PATCH v1 2/4] monitor/rfcomm: Add support for printing
> RFCOMM hdr
>
> Hi Gowtham,
>
> On Fri, Nov 7, 2014 at 3:06 PM, Gowtham Anandha Babu
> <[email protected]> wrote:
> > Changes made to decode RFCOMM hdr and print the same.
> >
> > RFCOMM: Unnumbered Info with Header Check (UIH)(0xef)
> > Address: 0x01 cr 0 dlci 0x00
> > Control: 0xef poll/final 0
> > Length: 10
> > FCS: 0xaa
> > 81 11 20 e0 27 00 9a 02 00 07 aa .. .'......
> >
> > ---
> > monitor/rfcomm.c | 50
> > +++++++++++++++++++++++++++++++++++++++++++++++---
> > 1 file changed, 47 insertions(+), 3 deletions(-)
> >
> > diff --git a/monitor/rfcomm.c b/monitor/rfcomm.c index
> > 155bde2..a70c404 100644
> > --- a/monitor/rfcomm.c
> > +++ b/monitor/rfcomm.c
> > @@ -44,6 +44,11 @@
> > #include "sdp.h"
> > #include "rfcomm.h"
> >
> > +#define GET_LEN8(length) ((length & 0xfe) >> 1) #define
> > +GET_LEN16(length) ((length & 0xfffe) >> 1)
> > +#define GET_CR(type) ((type & 0x02) >> 1)
> > +#define GET_PF(ctr) (((ctr) >> 4) & 0x1)
> > +
> > struct rfcomm_lhdr {
> > uint8_t address;
> > uint8_t control;
> > @@ -57,6 +62,24 @@ struct rfcomm_frame {
> > struct l2cap_frame l2cap_frame; };
> >
> > +static void print_rfcomm_hdr(struct rfcomm_frame *rfcomm_frame,
> > +uint8_t indent) {
> > + struct rfcomm_lhdr hdr = rfcomm_frame->hdr;
> > +
> > + /* Address field */
> > + print_field("%*cAddress: 0x%2.2x cr %d dlci 0x%2.2x", indent, ' ',
> > + hdr.address, GET_CR(hdr.address),
> > + RFCOMM_GET_DLCI(hdr.address));
> > +
> > + /* Control field */
> > + print_field("%*cControl: 0x%2.2x poll/final %d", indent, ' ',
> > + hdr.control,
> > + GET_PF(hdr.control));
> > +
> > + /* Length and FCS */
> > + print_field("%*cLength: %d", indent, ' ', hdr.length);
> > + print_field("%*cFCS: 0x%2.2x", indent, ' ', hdr.fcs); }
> > +
> > struct rfcomm_data {
> > uint8_t frame;
> > const char *str;
> > @@ -73,12 +96,13 @@ static const struct rfcomm_data rfcomm_table[] = {
> >
> > void rfcomm_packet(const struct l2cap_frame *frame) {
> > - uint8_t ctype;
> > + uint8_t ctype, length, ex_length, indent = 1;
> > const char *frame_str, *frame_color;
> > struct l2cap_frame *l2cap_frame;
> > struct rfcomm_frame rfcomm_frame;
> > struct rfcomm_lhdr hdr;
> > const struct rfcomm_data *rfcomm_data = NULL;
> > + const void *ptr;
> > int i;
> >
> > l2cap_frame_pull(&rfcomm_frame.l2cap_frame, frame, 0); @@
> > -89,9 +113,24 @@ void rfcomm_packet(const struct l2cap_frame *frame)
> > goto fail;
> >
> > if (!l2cap_frame_get_u8(l2cap_frame, &hdr.address) ||
> > - !l2cap_frame_get_u8(l2cap_frame, &hdr.control))
> > + !l2cap_frame_get_u8(l2cap_frame, &hdr.control) ||
> > + !l2cap_frame_get_u8(l2cap_frame, &length))
> > goto fail;
> >
> > + /* length maybe 1 or 2 octets */
> > + if (RFCOMM_TEST_EA(length))
> > + hdr.length = (uint16_t) GET_LEN8(length);
> > + else {
> > + if (!l2cap_frame_get_u8(l2cap_frame, &ex_length))
> > + goto fail;
> > + hdr.length = ((uint16_t)length << 8) | ex_length;
> > + hdr.length = GET_LEN16(hdr.length);
> > + }
> > +
> > + /* fetching FCS by frame offset */
> > + ptr = (l2cap_frame->data)+l2cap_frame->size-1;
> > + hdr.fcs = *(uint8_t *)(ptr);
>
> You should probably use l2cap_frame_pull followed by
> l2cap_frame_get_u8 so we actually check if the frame is too short.
> Btw, the format looks much better now.
>
> > /* Decoding frame type */
> > ctype = RFCOMM_GET_TYPE(hdr.control);
> >
> > @@ -122,7 +161,12 @@ void rfcomm_packet(const struct l2cap_frame
> *frame)
> > "(0x%2.2x)", ctype);
> >
> > rfcomm_frame.hdr = hdr;
> > - packet_hexdump(l2cap_frame->data, l2cap_frame->size);
> > + print_rfcomm_hdr(&rfcomm_frame, indent);
> > +
> > + /* UIH frame */
> > + if(ctype == 0xef)
> > + packet_hexdump(l2cap_frame->data, l2cap_frame->size);
> > +
> > return;
> >
> > fail:
> > --
> > 1.9.1
> >
> > --
> > To unsubscribe from this list: send the line "unsubscribe
> > linux-bluetooth" in the body of a message to [email protected]
> > More majordomo info at http://vger.kernel.org/majordomo-info.html
>
>
>
> --
> Luiz Augusto von Dentz
I will incorporate this in v2. Is there any other changes stills needs to be done?
Regards,
Gowtham
Hi Gowtham,
On Fri, Nov 7, 2014 at 3:06 PM, Gowtham Anandha Babu
<[email protected]> wrote:
> Changes made to decode RFCOMM hdr and print the same.
>
> RFCOMM: Unnumbered Info with Header Check (UIH)(0xef)
> Address: 0x01 cr 0 dlci 0x00
> Control: 0xef poll/final 0
> Length: 10
> FCS: 0xaa
> 81 11 20 e0 27 00 9a 02 00 07 aa .. .'......
>
> ---
> monitor/rfcomm.c | 50 +++++++++++++++++++++++++++++++++++++++++++++++---
> 1 file changed, 47 insertions(+), 3 deletions(-)
>
> diff --git a/monitor/rfcomm.c b/monitor/rfcomm.c
> index 155bde2..a70c404 100644
> --- a/monitor/rfcomm.c
> +++ b/monitor/rfcomm.c
> @@ -44,6 +44,11 @@
> #include "sdp.h"
> #include "rfcomm.h"
>
> +#define GET_LEN8(length) ((length & 0xfe) >> 1)
> +#define GET_LEN16(length) ((length & 0xfffe) >> 1)
> +#define GET_CR(type) ((type & 0x02) >> 1)
> +#define GET_PF(ctr) (((ctr) >> 4) & 0x1)
> +
> struct rfcomm_lhdr {
> uint8_t address;
> uint8_t control;
> @@ -57,6 +62,24 @@ struct rfcomm_frame {
> struct l2cap_frame l2cap_frame;
> };
>
> +static void print_rfcomm_hdr(struct rfcomm_frame *rfcomm_frame, uint8_t indent)
> +{
> + struct rfcomm_lhdr hdr = rfcomm_frame->hdr;
> +
> + /* Address field */
> + print_field("%*cAddress: 0x%2.2x cr %d dlci 0x%2.2x", indent, ' ',
> + hdr.address, GET_CR(hdr.address),
> + RFCOMM_GET_DLCI(hdr.address));
> +
> + /* Control field */
> + print_field("%*cControl: 0x%2.2x poll/final %d", indent, ' ',
> + hdr.control, GET_PF(hdr.control));
> +
> + /* Length and FCS */
> + print_field("%*cLength: %d", indent, ' ', hdr.length);
> + print_field("%*cFCS: 0x%2.2x", indent, ' ', hdr.fcs);
> +}
> +
> struct rfcomm_data {
> uint8_t frame;
> const char *str;
> @@ -73,12 +96,13 @@ static const struct rfcomm_data rfcomm_table[] = {
>
> void rfcomm_packet(const struct l2cap_frame *frame)
> {
> - uint8_t ctype;
> + uint8_t ctype, length, ex_length, indent = 1;
> const char *frame_str, *frame_color;
> struct l2cap_frame *l2cap_frame;
> struct rfcomm_frame rfcomm_frame;
> struct rfcomm_lhdr hdr;
> const struct rfcomm_data *rfcomm_data = NULL;
> + const void *ptr;
> int i;
>
> l2cap_frame_pull(&rfcomm_frame.l2cap_frame, frame, 0);
> @@ -89,9 +113,24 @@ void rfcomm_packet(const struct l2cap_frame *frame)
> goto fail;
>
> if (!l2cap_frame_get_u8(l2cap_frame, &hdr.address) ||
> - !l2cap_frame_get_u8(l2cap_frame, &hdr.control))
> + !l2cap_frame_get_u8(l2cap_frame, &hdr.control) ||
> + !l2cap_frame_get_u8(l2cap_frame, &length))
> goto fail;
>
> + /* length maybe 1 or 2 octets */
> + if (RFCOMM_TEST_EA(length))
> + hdr.length = (uint16_t) GET_LEN8(length);
> + else {
> + if (!l2cap_frame_get_u8(l2cap_frame, &ex_length))
> + goto fail;
> + hdr.length = ((uint16_t)length << 8) | ex_length;
> + hdr.length = GET_LEN16(hdr.length);
> + }
> +
> + /* fetching FCS by frame offset */
> + ptr = (l2cap_frame->data)+l2cap_frame->size-1;
> + hdr.fcs = *(uint8_t *)(ptr);
You should probably use l2cap_frame_pull followed by
l2cap_frame_get_u8 so we actually check if the frame is too short.
Btw, the format looks much better now.
> /* Decoding frame type */
> ctype = RFCOMM_GET_TYPE(hdr.control);
>
> @@ -122,7 +161,12 @@ void rfcomm_packet(const struct l2cap_frame *frame)
> "(0x%2.2x)", ctype);
>
> rfcomm_frame.hdr = hdr;
> - packet_hexdump(l2cap_frame->data, l2cap_frame->size);
> + print_rfcomm_hdr(&rfcomm_frame, indent);
> +
> + /* UIH frame */
> + if(ctype == 0xef)
> + packet_hexdump(l2cap_frame->data, l2cap_frame->size);
> +
> return;
>
> fail:
> --
> 1.9.1
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in
> the body of a message to [email protected]
> More majordomo info at http://vger.kernel.org/majordomo-info.html
--
Luiz Augusto von Dentz
Changes made to decode MCC frame in RFCOMM for btmon.
RFCOMM: Unnumbered Info with Header Check (UIH)(0xef)
Address: 0x01 cr 0 dlci 0x00
Control: 0xef poll/final 0
Length: 10
FCS: 0xaa
MCC Message type: DLC Parameter Negotiation RSP(0x20)
Length: 8
20 e0 27 00 9a 02 00 07 aa .'......
---
monitor/rfcomm.c | 83 ++++++++++++++++++++++++++++++++++++++++++++++++++++----
1 file changed, 78 insertions(+), 5 deletions(-)
diff --git a/monitor/rfcomm.c b/monitor/rfcomm.c
index 1a5c560..80e0556 100644
--- a/monitor/rfcomm.c
+++ b/monitor/rfcomm.c
@@ -44,6 +44,12 @@
#include "sdp.h"
#include "rfcomm.h"
+static char *cr_str[] = {
+ "RSP",
+ "CMD"
+};
+
+#define CR_STR(type) cr_str[GET_CR(type)]
#define GET_LEN8(length) ((length & 0xfe) >> 1)
#define GET_LEN16(length) ((length & 0xfffe) >> 1)
#define GET_CR(type) ((type & 0x02) >> 1)
@@ -57,8 +63,14 @@ struct rfcomm_lhdr {
uint8_t credits; /* only for UIH frame */
} __attribute__((packed));
+struct rfcomm_lmcc {
+ uint8_t type;
+ uint16_t length;
+} __attribute__((packed));
+
struct rfcomm_frame {
struct rfcomm_lhdr hdr;
+ struct rfcomm_lmcc mcc;
struct l2cap_frame l2cap_frame;
};
@@ -80,16 +92,78 @@ static void print_rfcomm_hdr(struct rfcomm_frame *rfcomm_frame, uint8_t indent)
print_field("%*cFCS: 0x%2.2x", indent, ' ', hdr.fcs);
}
+struct mcc_data {
+ uint8_t type;
+ const char *str;
+};
+
+static const struct mcc_data mcc_table[] = {
+ { 0x08, "Test Command" },
+ { 0x28, "Flow Control On Command" },
+ { 0x18, "Flow Control Off Command" },
+ { 0x38, "Modem Status Command" },
+ { 0x24, "Remote Port Negotiation Command" },
+ { 0x14, "Remote Line Status" },
+ { 0x20, "DLC Parameter Negotiation" },
+ { 0x04, "Non Supported Command" },
+ { }
+};
+
+static inline bool mcc_frame(struct rfcomm_frame *rfcomm_frame, uint8_t indent)
+{
+ uint8_t length, ex_length, type;
+ const char *type_str;
+ int i;
+ struct l2cap_frame *frame = &rfcomm_frame->l2cap_frame;
+ struct rfcomm_lmcc mcc;
+ const struct mcc_data *mcc_data = NULL;
+
+ if (!l2cap_frame_get_u8(frame, &mcc.type) ||
+ !l2cap_frame_get_u8(frame, &length))
+ return false;
+
+ if (RFCOMM_TEST_EA(length))
+ mcc.length = (uint16_t) GET_LEN8(length);
+ else {
+ if (!l2cap_frame_get_u8(frame, &ex_length))
+ return false;
+ mcc.length = ((uint16_t) length << 8) | ex_length;
+ mcc.length = GET_LEN16(mcc.length);
+ }
+
+ type = RFCOMM_GET_MCC_TYPE(mcc.type);
+
+ for (i = 0; mcc_table[i].str; i++) {
+ if (mcc_table[i].type == type) {
+ mcc_data = &mcc_table[i];
+ break;
+ }
+ }
+
+ if (mcc_data)
+ type_str = mcc_data->str;
+ else
+ type_str = "Unknown";
+
+ print_field("%*cMCC Message type: %s %s(0x%2.2x)", indent, ' ',
+ type_str, CR_STR(mcc.type), type);
+
+ print_field("%*cLength: %d", indent+2, ' ', mcc.length);
+
+ rfcomm_frame->mcc = mcc;
+ packet_hexdump(frame->data, frame->size);
+
+ return true;
+}
+
static bool uih_frame(struct rfcomm_frame *rfcomm_frame, uint8_t indent)
{
uint8_t credits;
struct l2cap_frame *frame = &rfcomm_frame->l2cap_frame;
struct rfcomm_lhdr *hdr = &rfcomm_frame->hdr;
- if (!RFCOMM_GET_CHANNEL(hdr->address)) {
- /* MCC frame parser implementation */
- goto done;
- }
+ if (!RFCOMM_GET_CHANNEL(hdr->address))
+ return mcc_frame(rfcomm_frame, indent);
/* fetching credits from UIH frame */
if (GET_PF(hdr->control)) {
@@ -100,7 +174,6 @@ static bool uih_frame(struct rfcomm_frame *rfcomm_frame, uint8_t indent)
return true;
}
-done:
packet_hexdump(frame->data, frame->size);
return true;
}
--
1.9.1
Changes made to decode UIH frame in btmon.
In below UIH frame, MCC frame is present, so no credits field is printed.
RFCOMM: Unnumbered Info with Header Check (UIH)(0xef)
Address: 0x01 cr 0 dlci 0x00
Control: 0xef poll/final 0
Length: 10
FCS: 0xaa
81 11 20 e0 27 00 9a 02 00 07 aa .. .'......
In this UIH frame, no MCC frame, so credits field is printed.
RFCOMM: Unnumbered Info with Header Check (UIH)(0xef)
Address: 0x81 cr 0 dlci 0x20
Control: 0xff poll/final 1
Length: 0
FCS: 0x1e
Credits : 33
---
monitor/rfcomm.c | 30 ++++++++++++++++++++++++++++--
1 file changed, 28 insertions(+), 2 deletions(-)
diff --git a/monitor/rfcomm.c b/monitor/rfcomm.c
index a70c404..1a5c560 100644
--- a/monitor/rfcomm.c
+++ b/monitor/rfcomm.c
@@ -80,6 +80,31 @@ static void print_rfcomm_hdr(struct rfcomm_frame *rfcomm_frame, uint8_t indent)
print_field("%*cFCS: 0x%2.2x", indent, ' ', hdr.fcs);
}
+static bool uih_frame(struct rfcomm_frame *rfcomm_frame, uint8_t indent)
+{
+ uint8_t credits;
+ struct l2cap_frame *frame = &rfcomm_frame->l2cap_frame;
+ struct rfcomm_lhdr *hdr = &rfcomm_frame->hdr;
+
+ if (!RFCOMM_GET_CHANNEL(hdr->address)) {
+ /* MCC frame parser implementation */
+ goto done;
+ }
+
+ /* fetching credits from UIH frame */
+ if (GET_PF(hdr->control)) {
+ if (!l2cap_frame_get_u8(frame, &credits))
+ return false;
+ hdr->credits = credits;
+ print_field("%*cCredits: %d", indent, ' ', hdr->credits);
+ return true;
+ }
+
+done:
+ packet_hexdump(frame->data, frame->size);
+ return true;
+}
+
struct rfcomm_data {
uint8_t frame;
const char *str;
@@ -164,8 +189,9 @@ void rfcomm_packet(const struct l2cap_frame *frame)
print_rfcomm_hdr(&rfcomm_frame, indent);
/* UIH frame */
- if(ctype == 0xef)
- packet_hexdump(l2cap_frame->data, l2cap_frame->size);
+ if (ctype == 0xef)
+ if (!uih_frame(&rfcomm_frame, indent))
+ goto fail;
return;
--
1.9.1
Changes made to decode RFCOMM hdr and print the same.
RFCOMM: Unnumbered Info with Header Check (UIH)(0xef)
Address: 0x01 cr 0 dlci 0x00
Control: 0xef poll/final 0
Length: 10
FCS: 0xaa
81 11 20 e0 27 00 9a 02 00 07 aa .. .'......
---
monitor/rfcomm.c | 50 +++++++++++++++++++++++++++++++++++++++++++++++---
1 file changed, 47 insertions(+), 3 deletions(-)
diff --git a/monitor/rfcomm.c b/monitor/rfcomm.c
index 155bde2..a70c404 100644
--- a/monitor/rfcomm.c
+++ b/monitor/rfcomm.c
@@ -44,6 +44,11 @@
#include "sdp.h"
#include "rfcomm.h"
+#define GET_LEN8(length) ((length & 0xfe) >> 1)
+#define GET_LEN16(length) ((length & 0xfffe) >> 1)
+#define GET_CR(type) ((type & 0x02) >> 1)
+#define GET_PF(ctr) (((ctr) >> 4) & 0x1)
+
struct rfcomm_lhdr {
uint8_t address;
uint8_t control;
@@ -57,6 +62,24 @@ struct rfcomm_frame {
struct l2cap_frame l2cap_frame;
};
+static void print_rfcomm_hdr(struct rfcomm_frame *rfcomm_frame, uint8_t indent)
+{
+ struct rfcomm_lhdr hdr = rfcomm_frame->hdr;
+
+ /* Address field */
+ print_field("%*cAddress: 0x%2.2x cr %d dlci 0x%2.2x", indent, ' ',
+ hdr.address, GET_CR(hdr.address),
+ RFCOMM_GET_DLCI(hdr.address));
+
+ /* Control field */
+ print_field("%*cControl: 0x%2.2x poll/final %d", indent, ' ',
+ hdr.control, GET_PF(hdr.control));
+
+ /* Length and FCS */
+ print_field("%*cLength: %d", indent, ' ', hdr.length);
+ print_field("%*cFCS: 0x%2.2x", indent, ' ', hdr.fcs);
+}
+
struct rfcomm_data {
uint8_t frame;
const char *str;
@@ -73,12 +96,13 @@ static const struct rfcomm_data rfcomm_table[] = {
void rfcomm_packet(const struct l2cap_frame *frame)
{
- uint8_t ctype;
+ uint8_t ctype, length, ex_length, indent = 1;
const char *frame_str, *frame_color;
struct l2cap_frame *l2cap_frame;
struct rfcomm_frame rfcomm_frame;
struct rfcomm_lhdr hdr;
const struct rfcomm_data *rfcomm_data = NULL;
+ const void *ptr;
int i;
l2cap_frame_pull(&rfcomm_frame.l2cap_frame, frame, 0);
@@ -89,9 +113,24 @@ void rfcomm_packet(const struct l2cap_frame *frame)
goto fail;
if (!l2cap_frame_get_u8(l2cap_frame, &hdr.address) ||
- !l2cap_frame_get_u8(l2cap_frame, &hdr.control))
+ !l2cap_frame_get_u8(l2cap_frame, &hdr.control) ||
+ !l2cap_frame_get_u8(l2cap_frame, &length))
goto fail;
+ /* length maybe 1 or 2 octets */
+ if (RFCOMM_TEST_EA(length))
+ hdr.length = (uint16_t) GET_LEN8(length);
+ else {
+ if (!l2cap_frame_get_u8(l2cap_frame, &ex_length))
+ goto fail;
+ hdr.length = ((uint16_t)length << 8) | ex_length;
+ hdr.length = GET_LEN16(hdr.length);
+ }
+
+ /* fetching FCS by frame offset */
+ ptr = (l2cap_frame->data)+l2cap_frame->size-1;
+ hdr.fcs = *(uint8_t *)(ptr);
+
/* Decoding frame type */
ctype = RFCOMM_GET_TYPE(hdr.control);
@@ -122,7 +161,12 @@ void rfcomm_packet(const struct l2cap_frame *frame)
"(0x%2.2x)", ctype);
rfcomm_frame.hdr = hdr;
- packet_hexdump(l2cap_frame->data, l2cap_frame->size);
+ print_rfcomm_hdr(&rfcomm_frame, indent);
+
+ /* UIH frame */
+ if(ctype == 0xef)
+ packet_hexdump(l2cap_frame->data, l2cap_frame->size);
+
return;
fail:
--
1.9.1
Changes made to add initial code to support RFCOMM frame in btmon
btmon logs:
RFCOMM: Set Async Balance Mode (SABM) (0x2f)
01 1c ..
RFCOMM: Unnumbered Ack (UA)(0x63)
01 d7 ..
RFCOMM: Unnumbered Info with Header Check (UIH)(0xef)
15 81 11 20 e0 27 00 9a 02 00 07 aa ... .'......
RFCOMM: Disconnect (DISC)(0x43)
01 fd ..
---
Makefile.tools | 1 +
android/Android.mk | 1 +
monitor/l2cap.c | 4 ++
monitor/l2cap.h | 1 +
monitor/rfcomm.c | 132 +++++++++++++++++++++++++++++++++++++++++++++++++++++
5 files changed, 139 insertions(+)
create mode 100644 monitor/rfcomm.c
diff --git a/Makefile.tools b/Makefile.tools
index 42cccc6..75a6faa 100644
--- a/Makefile.tools
+++ b/Makefile.tools
@@ -26,6 +26,7 @@ monitor_btmon_SOURCES = monitor/main.c monitor/bt.h \
monitor/l2cap.h monitor/l2cap.c \
monitor/sdp.h monitor/sdp.c \
monitor/avctp.h monitor/avctp.c \
+ monitor/rfcomm.h monitor/rfcomm.c \
monitor/uuid.h monitor/uuid.c \
monitor/hwdb.h monitor/hwdb.c \
monitor/keys.h monitor/keys.c \
diff --git a/android/Android.mk b/android/Android.mk
index aefe41c..eebd863 100644
--- a/android/Android.mk
+++ b/android/Android.mk
@@ -289,6 +289,7 @@ LOCAL_SRC_FILES := \
bluez/monitor/packet.c \
bluez/monitor/l2cap.c \
bluez/monitor/avctp.c \
+ bluez/monitor/rfcomm.c \
bluez/monitor/uuid.c \
bluez/monitor/sdp.c \
bluez/monitor/vendor.c \
diff --git a/monitor/l2cap.c b/monitor/l2cap.c
index c004d6b..ebdd20f 100644
--- a/monitor/l2cap.c
+++ b/monitor/l2cap.c
@@ -42,6 +42,7 @@
#include "keys.h"
#include "sdp.h"
#include "avctp.h"
+#include "rfcomm.h"
#define MAX_CHAN 64
@@ -2643,6 +2644,9 @@ static void l2cap_frame(uint16_t index, bool in, uint16_t handle,
case 0x0001:
sdp_packet(&frame);
break;
+ case 0x0003:
+ rfcomm_packet(&frame);
+ break;
case 0x001f:
att_packet(index, in, handle, cid, data, size);
break;
diff --git a/monitor/l2cap.h b/monitor/l2cap.h
index 5faaea6..1f70b68 100644
--- a/monitor/l2cap.h
+++ b/monitor/l2cap.h
@@ -153,3 +153,4 @@ static inline bool l2cap_frame_get_le64(struct l2cap_frame *frame,
void l2cap_packet(uint16_t index, bool in, uint16_t handle, uint8_t flags,
const void *data, uint16_t size);
+void rfcomm_packet(const struct l2cap_frame *frame);
diff --git a/monitor/rfcomm.c b/monitor/rfcomm.c
new file mode 100644
index 0000000..155bde2
--- /dev/null
+++ b/monitor/rfcomm.c
@@ -0,0 +1,132 @@
+/*
+ *
+ * BlueZ - Bluetooth protocol stack for Linux
+ *
+ * Copyright (C) 2011-2014 Intel Corporation
+ * Copyright (C) 2002-2010 Marcel Holtmann <[email protected]>
+ *
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+#include <inttypes.h>
+
+#include <bluetooth/bluetooth.h>
+
+#include "src/shared/util.h"
+#include "bt.h"
+#include "packet.h"
+#include "display.h"
+#include "l2cap.h"
+#include "uuid.h"
+#include "keys.h"
+#include "sdp.h"
+#include "rfcomm.h"
+
+struct rfcomm_lhdr {
+ uint8_t address;
+ uint8_t control;
+ uint16_t length;
+ uint8_t fcs;
+ uint8_t credits; /* only for UIH frame */
+} __attribute__((packed));
+
+struct rfcomm_frame {
+ struct rfcomm_lhdr hdr;
+ struct l2cap_frame l2cap_frame;
+};
+
+struct rfcomm_data {
+ uint8_t frame;
+ const char *str;
+};
+
+static const struct rfcomm_data rfcomm_table[] = {
+ { 0x2f, "Set Async Balance Mode (SABM) " },
+ { 0x63, "Unnumbered Ack (UA)" },
+ { 0x0f, "Disconnect Mode (DM)" },
+ { 0x43, "Disconnect (DISC)" },
+ { 0xef, "Unnumbered Info with Header Check (UIH)" },
+ { }
+};
+
+void rfcomm_packet(const struct l2cap_frame *frame)
+{
+ uint8_t ctype;
+ const char *frame_str, *frame_color;
+ struct l2cap_frame *l2cap_frame;
+ struct rfcomm_frame rfcomm_frame;
+ struct rfcomm_lhdr hdr;
+ const struct rfcomm_data *rfcomm_data = NULL;
+ int i;
+
+ l2cap_frame_pull(&rfcomm_frame.l2cap_frame, frame, 0);
+
+ l2cap_frame = &rfcomm_frame.l2cap_frame;
+
+ if (frame->size < 4)
+ goto fail;
+
+ if (!l2cap_frame_get_u8(l2cap_frame, &hdr.address) ||
+ !l2cap_frame_get_u8(l2cap_frame, &hdr.control))
+ goto fail;
+
+ /* Decoding frame type */
+ ctype = RFCOMM_GET_TYPE(hdr.control);
+
+ for (i = 0; rfcomm_table[i].str; i++) {
+ if (rfcomm_table[i].frame == ctype) {
+ rfcomm_data = &rfcomm_table[i];
+ break;
+ }
+ }
+
+ if (rfcomm_data) {
+ if (frame->in)
+ frame_color = COLOR_MAGENTA;
+ else
+ frame_color = COLOR_BLUE;
+ frame_str = rfcomm_data->str;
+ } else {
+ frame_color = COLOR_WHITE_BG;
+ frame_str = "Unknown";
+ }
+
+ if (!rfcomm_data) {
+ packet_hexdump(frame->data, frame->size);
+ return;
+ }
+
+ print_indent(6, frame_color, "RFCOMM: ", frame_str, COLOR_OFF,
+ "(0x%2.2x)", ctype);
+
+ rfcomm_frame.hdr = hdr;
+ packet_hexdump(l2cap_frame->data, l2cap_frame->size);
+ return;
+
+fail:
+ print_text(COLOR_ERROR, "Frame too short");
+ packet_hexdump(frame->data, frame->size);
+ return;
+}
--
1.9.1