1 * For the user
2 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3 NOTE: This document describes the usage of the high level CI API as
4 in accordance to the Linux DVB API. This is a not a documentation for the,
5 existing low level CI API.
6 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
7
8 To utilize the High Level CI capabilities,
9
10 (1*) This point is valid only for the Twinhan/clones
11 For the Twinhan/Twinhan clones, the dst_ca module handles the CI
12 hardware handling.This module is loaded automatically if a CI
13 (Common Interface, that holds the CAM (Conditional Access Module)
14 is detected.
15
16 (2) one requires a userspace application, ca_zap. This small userland
17 application is in charge of sending the descrambling related information
18 to the CAM.
19
20 This application requires the following to function properly as of now.
21
22 (a) Tune to a valid channel, with szap.
23 eg: $ szap -c channels.conf -r "TMC" -x
24
25 (b) a channels.conf containing a valid PMT PID
26 eg: TMC:11996:h:0:27500:278:512:650:321
27
28 here 278 is a valid PMT PID. the rest of the values are the
29 same ones that szap uses.
30
31 (c) after running a szap, you have to run ca_zap, for the
32 descrambler to function,
33 eg: $ ca_zap channels.conf "TMC"
34
35 (d) Hopeflly Enjoy your favourite subscribed channel as you do with
36 a FTA card.
37
38 (3) Currently ca_zap, and dst_test, both are meant for demonstration
39 purposes only, they can become full fledged applications if necessary.
40
41
42 * Cards that fall in this category
43 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
44 At present the cards that fall in this category are the Twinhan and it's
45 clones, these cards are available as VVMER, Tomato, Hercules, Orange and
46 so on.
47
48 * CI modules that are supported
49 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
50 The CI module support is largely dependant upon the firmware on the cards
51 Some cards do support almost all of the available CI modules. There is
52 nothing much that can be done in order to make additional CI modules
53 working with these cards.
54
55 Modules that have been tested by this driver at present are
56
57 (1) Irdeto 1 and 2 from SCM
58 (2) Viaccess from SCM
59 (3) Dragoncam
60
61 * The High level CI API
62 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
63
64 * For the programmer
65 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
66 With the High Level CI approach any new card with almost any random
67 architecture can be implemented with this style, the definitions
68 insidethe switch statement can be easily adapted for any card, thereby
69 eliminating the need for any additional ioctls.
70
71 The disadvantage is that the driver/hardware has to manage the rest. For
72 the application programmer it would be as simple as sending/receiving an
73 array to/from the CI ioctls as defined in the Linux DVB API. No changes
74 have been made in the API to accomodate this feature.
75
76
77 * Why the need for another CI interface ?
78 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
79 This is one of the most commonly asked question. Well a nice question.
80 Strictly speaking this is not a new interface.
81
82 The CI interface is defined in the DVB API in ca.h as
83
84 typedef struct ca_slot_info {
85 int num; /* slot number */
86
87 int type; /* CA interface this slot supports */
88 #define CA_CI 1 /* CI high level interface */
89 #define CA_CI_LINK 2 /* CI link layer level interface */
90 #define CA_CI_PHYS 4 /* CI physical layer level interface */
91 #define CA_DESCR 8 /* built-in descrambler */
92 #define CA_SC 128 /* simple smart card interface */
93
94 unsigned int flags;
95 #define CA_CI_MODULE_PRESENT 1 /* module (or card) inserted */
96 #define CA_CI_MODULE_READY 2
97 } ca_slot_info_t;
98
99
100
101 This CI interface follows the CI high level interface, which is not
102 implemented by most applications. Hence this area is revisited.
103
104 This CI interface is quite different in the case that it tries to
105 accomodate all other CI based devices, that fall into the other categories
106
107 This means that this CI interface handles the EN50221 style tags in the
108 Application layer only and no session management is taken care of by the
109 application. The driver/hardware will take care of all that.
110
111 This interface is purely an EN50221 interface exchanging APDU's. This
112 means that no session management, link layer or a transport layer do
113 exist in this case in the application to driver communication. It is
114 as simple as that. The driver/hardware has to take care of that.
115
116
117 With this High Level CI interface, the interface can be defined with the
118 regular ioctls.
119
120 All these ioctls are also valid for the High level CI interface
121
122 #define CA_RESET _IO('o', 128)
123 #define CA_GET_CAP _IOR('o', 129, ca_caps_t)
124 #define CA_GET_SLOT_INFO _IOR('o', 130, ca_slot_info_t)
125 #define CA_GET_DESCR_INFO _IOR('o', 131, ca_descr_info_t)
126 #define CA_GET_MSG _IOR('o', 132, ca_msg_t)
127 #define CA_SEND_MSG _IOW('o', 133, ca_msg_t)
128 #define CA_SET_DESCR _IOW('o', 134, ca_descr_t)
129 #define CA_SET_PID _IOW('o', 135, ca_pid_t)
130
131
132 On querying the device, the device yields information thus
133
134 CA_GET_SLOT_INFO
135 ----------------------------
136 Command = [info]
137 APP: Number=[1]
138 APP: Type=[1]
139 APP: flags=[1]
140 APP: CI High level interface
141 APP: CA/CI Module Present
142
143 CA_GET_CAP
144 ----------------------------
145 Command = [caps]
146 APP: Slots=[1]
147 APP: Type=[1]
148 APP: Descrambler keys=[16]
149 APP: Type=[1]
150
151 CA_SEND_MSG
152 ----------------------------
153 Descriptors(Program Level)=[ 09 06 06 04 05 50 ff f1]
154 Found CA descriptor @ program level
155
156 (20) ES type=[2] ES pid=[201] ES length =[0 (0x0)]
157 (25) ES type=[4] ES pid=[301] ES length =[0 (0x0)]
158 ca_message length is 25 (0x19) bytes
159 EN50221 CA MSG=[ 9f 80 32 19 03 01 2d d1 f0 08 01 09 06 06 04 05 50 ff f1 02 e0 c9 00 00 04 e1 2d 00 00]
160
161
162 Not all ioctl's are implemented in the driver from the API, the other
163 features of the hardware that cannot be implemented by the API are achieved
164 using the CA_GET_MSG and CA_SEND_MSG ioctls. An EN50221 style wrapper is
165 used to exchange the data to maintain compatibility with other hardware.
166
167
168 /* a message to/from a CI-CAM */
169 typedef struct ca_msg {
170 unsigned int index;
171 unsigned int type;
172 unsigned int length;
173 unsigned char msg[256];
174 } ca_msg_t;
175
176
177 The flow of data can be described thus,
178
179
180
181
182
183 App (User)
184 -----
185 parse
186 |
187 |
188 v
189 en50221 APDU (package)
190 --------------------------------------
191 | | | High Level CI driver
192 | | |
193 | v |
194 | en50221 APDU (unpackage) |
195 | | |
196 | | |
197 | v |
198 | sanity checks |
199 | | |
200 | | |
201 | v |
202 | do (H/W dep) |
203 --------------------------------------
204 | Hardware
205 |
206 v
207
208
209
210
211 The High Level CI interface uses the EN50221 DVB standard, following a
212 standard ensures futureproofness.
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