]> sigrok.org Git - libsigrokdecode.git/commitdiff
Add HDCP traffic decoder to stack on i2c
authorDave Craig <redacted>
Wed, 2 Jan 2019 13:36:11 +0000 (13:36 +0000)
committerUwe Hermann <redacted>
Sat, 7 Dec 2019 15:32:02 +0000 (16:32 +0100)
This decoder annotates i2c traffic to indicate the type of HDCP
message contained. It includes HDCP2.2 and HDCP1.4. Useful for
analysing HDCP negotiation failures.

decoders/hdcp/__init__.py [new file with mode: 0644]
decoders/hdcp/pd.py [new file with mode: 0644]

diff --git a/decoders/hdcp/__init__.py b/decoders/hdcp/__init__.py
new file mode 100644 (file)
index 0000000..8ead98b
--- /dev/null
@@ -0,0 +1,27 @@
+##
+## This file is part of the libsigrokdecode project.
+##
+## Copyright (C) 2018 Dave Craig<dcraig@brightsign.biz>
+##
+## 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/>.
+##
+
+'''
+This decoder stacks on top of the 'i2c' PD and decodes HDCP messages.
+
+Details:
+https://www.digital-cp.com/sites/default/files/specifications/HDCP%20on%20HDMI%20Specification%20Rev2_2_Final1.pdf
+'''
+
+from .pd import Decoder
diff --git a/decoders/hdcp/pd.py b/decoders/hdcp/pd.py
new file mode 100644 (file)
index 0000000..861cd5c
--- /dev/null
@@ -0,0 +1,204 @@
+##
+## This file is part of the libsigrokdecode project.
+##
+## Copyright (C) 2018 Dave Craig<dcraig@brightsign.biz>
+##
+## 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/>.
+##
+
+import sigrokdecode as srd
+
+msg_ids = {
+    2: 'AKE_Init',
+    3: 'AKE_Send_Cert',
+    4: 'AKE_No_stored_km',
+    5: 'AKE_Stored_km',
+
+    7: 'AKE_Send_H_prime',
+    8: 'AKE_Send_Pairing_Info',
+
+    9: 'LC_Init',
+    10: 'LC_Send_L_prime',
+
+    11: 'SKE_Send_Eks',
+    12: 'RepeaterAuth_Send_ReceiverID_List',
+
+    15: 'RepeaterAuth_Send_Ack',
+    16: 'RepeaterAuth_Stream_Manage',
+    17: 'RepeaterAuth_Stream_Ready',
+}
+
+class Decoder(srd.Decoder):
+    api_version = 3
+    id = 'hdcp'
+    name = 'HDCP'
+    longname = 'HDCP over HDMI'
+    desc = 'HDCP protocol over HDMI.'
+    license = 'gplv2+'
+    inputs = ['i2c']
+    outputs = ['hdcp']
+    annotations = \
+        tuple(('message-0x%02X' % i, 'Message 0x%02X' % i) for i in range(18)) + (
+        ('summary', 'Summary'),
+        ('warnings', 'Warnings'),
+    )
+    annotation_rows = (
+        ('messages', 'Messages', tuple(range(18))),
+        ('summary', 'Summary', (18,)),
+        ('warnings', 'Warnings', (19,)),
+    )
+
+    def __init__(self):
+        self.reset()
+
+    def reset(self):
+        self.state = 'IDLE'
+        self.stack = []
+        self.msg = -1
+        self.ss = self.es = self.ss_block = self.es_block = 0
+        self.init_seq = []
+        self.valid = 0
+        self.type = ''
+
+    def start(self):
+        self.out_ann = self.register(srd.OUTPUT_ANN)
+
+    def putb(self, data):
+        self.put(self.ss_block, self.es_block, self.out_ann, data)
+
+    def decode(self, ss, es, data):
+        cmd, databyte = data
+
+        # Collect the 'BITS' packet, then return. The next packet is
+        # guaranteed to belong to these bits we just stored.
+        if cmd == 'BITS':
+            self.bits = databyte
+            return
+
+        self.ss, self.es = ss, es
+
+        # State machine.
+        if self.state == 'IDLE':
+            # Wait for an I2C START condition.
+            if cmd == 'START':
+                self.reset()
+                self.ss_block = ss
+            elif cmd != 'START REPEAT':
+                return
+            self.state = 'GET SLAVE ADDR'
+
+        elif self.state == 'GET SLAVE ADDR':
+            if cmd == 'ADDRESS READ':
+                self.state = 'BUFFER DATA'
+                if databyte != 0x3a:
+                    self.state = 'IDLE'
+            elif cmd == 'ADDRESS WRITE':
+                self.state = 'WRITE OFFSET'
+                if databyte != 0x3a:
+                    self.state = 'IDLE'
+
+        elif self.state == 'WRITE OFFSET':
+            if cmd == 'DATA WRITE':
+                if databyte == 0x00:
+                    self.type = '1.4 Bksv - Receiver KSV'
+                elif databyte == 0x08:
+                    self.type = '1.4 Ri\' - Link Verification'
+                elif databyte == 0x0a:
+                    self.type = '1.4 Pj\' - Enhanced Link Verification'
+                elif databyte == 0x10:
+                    self.type = '1.4 Aksv - Transmitter KSV'
+                    self.state = 'BUFFER DATA'
+                elif databyte == 0x15:
+                    self.type = '1.4 Ainfo- Transmitter KSV'
+                    self.state = 'BUFFER DATA'
+                elif databyte == 0x18:
+                    self.type = '1.4 An- Session random number'
+                    self.state = 'BUFFER DATA'
+                elif databyte == 0x20:
+                    self.type = '1.4 V\'H0'
+                elif databyte == 0x24:
+                    self.type = '1.4 V\'H1'
+                elif databyte == 0x28:
+                    self.type = '1.4 V\'H2'
+                elif databyte == 0x2c:
+                    self.type = '1.4 V\'H3'
+                elif databyte == 0x30:
+                    self.type = '1.4 V\'H4'
+                elif databyte == 0x40:
+                    self.type = '1.4 Bcaps'
+                elif databyte == 0x41:
+                    self.type = '1.4 Bstatus'
+                elif databyte == 0x43:
+                    self.type = '1.4 KSV FIFO'
+                elif databyte == 0x50:
+                    self.type = 'HDCP2Version'
+                elif databyte == 0x60:
+                    self.type = 'Write_Message'
+                    self.state = 'BUFFER DATA'
+                elif databyte == 0x70:
+                    self.type = 'RxStatus'
+                elif databyte == 0x80:
+                    self.type = 'Read_Message'
+
+                # If we are reading, then jump back to IDLE for a start repeat.
+                # If we are writing, then just continue onwards.
+                if self.state == 'BUFFER DATA':
+                    self.state = 'BUFFER DATA'
+                elif self.type != '':
+                    self.state = 'IDLE'
+
+        elif self.state == 'BUFFER DATA':
+            if (cmd == 'STOP') or (cmd == 'NACK'):
+                self.es_block = es
+                self.state = 'IDLE'
+                if self.type != '':
+                    if self.stack:
+                        if self.type == 'RxStatus':
+                            rxstatus = (self.stack.pop() << 8) | self.stack.pop()
+                            reauth_req = (rxstatus & 0x800) != 0
+                            ready = (rxstatus & 0x400) != 0
+                            length = rxstatus & 0x3ff
+                            text = '%s, reauth %s, ready %s, length %s' % (self.type, reauth_req, ready, length)
+                            self.putb([18, [text]])
+                        elif self.type == '1.4 Bstatus':
+                            bstatus = (self.stack.pop() << 8) | self.stack.pop()
+                            device_count = bstatus & 0x7f
+                            max_devs_exceeded = (bstatus & 0x80) != 0
+                            depth = ((bstatus & 0x700) >> 8)
+                            max_cascase_exceeded = bstatus & 0x800
+                            hdmi_mode = (bstatus & 0x1000) != 0
+                            text = '%s, %s devices, depth %s, hdmi mode %s' % (self.type, device_count, depth, hdmi_mode)
+                            self.putb([18, [text]])
+                        elif self.type == 'Read_Message':
+                            msg = self.stack.pop(0)
+                            self.putb([msg, ['%s, %s' % (self.type, msg_ids.get(msg, 'Invalid'))]])
+                        elif self.type == 'Write_Message':
+                            msg = self.stack.pop(0)
+                            self.putb([msg, ['%s, %s' % (self.type, msg_ids.get(msg, 'Invalid'))]])
+                        elif self.type == 'HDCP2Version':
+                            version = self.stack.pop(0)
+                            if (version & 0x4):
+                                self.putb([18, ['HDCP2']])
+                            else:
+                                self.putb([18, ['NOT HDCP2']])
+                        else:
+                            self.putb([18, ['%s' % (self.type)]])
+                    else:
+                        self.putb([18, ['%s' % (self.type)]])
+            elif cmd == 'DATA READ':
+                # Stack up our data bytes.
+                self.stack.append(databyte)
+            elif cmd == 'DATA WRITE':
+                # Stack up our data bytes.
+                self.stack.append(databyte)