xref: /dragonfly/sys/netgraph/NOTES (revision 984263bc)
1$FreeBSD: src/sys/netgraph/NOTES,v 1.1 1999/10/21 09:05:51 julian Exp $
2Development ideas..
3
4Archie's suggestions... :-)
5
6 - There should be a new malloc type: M_NETGRAPH
7	[DONE]
8	- all mallocs/frees now changed to use this.. JRE
9	- might further split them out some time.
10
11 - Use MALLOC and FREE macros instead of direct function calls
12	[DONE]
13	- They allow conditional compilation which keeps
14	  statistics & counters on various memory allocation
15	  (or so it seems)
16
17 - In struct ng_mesg: at least make "header" into "hdr", if not
18   getting rid of it altogether. It doesn't seem necessary and
19   makes all my C code lines too long.
20
21	- I understand.. one thought however.. consider..
22	  if char data[0] were not legal,  so that data[1] needed to be
23	  used instead, then the only way to get the size of the header
24	  would be sizeof(msg.header) as sizeof(msg) would include the dummy
25	  following bytes. this is a portability issue and I hope
26	  it will be ported eventually :)
27
28	- Baloney! you can use sizeof(msg) - 1 then.. or just
29	  make it a macro, then its always portable:
30
31	  #ifdef __GNU_C__
32	    #define NG_MSG_HDR_SIZE	(sizeof(struct ng_message))
33	  #else
34	    #define NG_MSG_HDR_SIZE	(sizeof(struct ng_message) - 1)
35	  #endif
36
37 - Have a user level program to print out and manipulate nodes, etc.
38	- [DONE]
39		see ngctl
40
41 - "Netgraph global" flags to turn on tracing, etc.
42
43 - ngctl needs to be rewritten using libnetgraph. Also it needs a
44   command to list all existing nodes (in case you don't know the
45   name of what you're looking for).
46	[DONE]
47
48 - Need a way to get a list of ALL nodes.
49	[DONE]
50	- see NGM_LISTNODES
51
52 - Enhance "netstat" to display all netgraph nodes -- or at least
53   all netgraph socket nodes.
54	[DONE]
55
56 - BUG FIX: bind() on a socket should neither require nor allow a
57   colon character at the end of the name. Note ngctl allows you
58   to do it either way!
59	[DONE] (I think)
60
61 - Need to implement passing meta information through socket nodes
62   using sendmsg() and recvmsg().
63
64 - Stuff needing to be added to manual:
65
66   - Awareness of SPL level, use ng_queue*() functions when necessary.
67   - Malloc all memory with type M_NETGRAPH.
68   - Write code so it can be an LKM or built into the kernel.. this means
69     be careful with things like #ifdef INET.
70   - All nodes assume that all data mbufs have the M_PKTHDR flag set!
71     The ng_send_data() and related functions should have an
72     #ifdef DIAGNOSTICS check to check this assumption for every mbuf.
73   - More generally, netgraph code should make liberal use of the
74     #ifdef DIAGNOSTICS definition.
75   - Since data and messages are sent functionally, programmers need
76     to watch out for infinite feedback loops. Should ng_base.c detect
77     this automatically?
78      - I've been thinking about this. each node could have a 'colour'
79	which is set to the colour of the packet as you pass through.
80	hitting a node already of your colour would abort. Each packet
81	has another (incremented) colour.
82