[B.A.T.M.A.N.] [PATCH] batman-adv: move the ttl field to the third position of unicast_* packets
Move the ttl field to the third position of unicast_packet and unicast_frag_packet. In this way it possible to give them a better shape for later usage
Signed-off-by: Antonio Quartulli ordex@autistici.org --- packet.h | 9 ++++++--- 1 files changed, 6 insertions(+), 3 deletions(-)
diff --git a/packet.h b/packet.h index eda9965..e464ceb 100644 --- a/packet.h +++ b/packet.h @@ -32,7 +32,7 @@ #define BAT_UNICAST_FRAG 0x06
/* this file is included by batctl which needs these defines */ -#define COMPAT_VERSION 12 +#define COMPAT_VERSION 14 #define DIRECTLINK 0x40 #define VIS_SERVER 0x20 #define PRIMARIES_FIRST_HOP 0x10 @@ -99,16 +99,19 @@ struct icmp_packet_rr { struct unicast_packet { uint8_t packet_type; uint8_t version; /* batman version field */ - uint8_t dest[6]; uint8_t ttl; + uint8_t align; + uint8_t dest[6]; } __packed;
struct unicast_frag_packet { uint8_t packet_type; uint8_t version; /* batman version field */ - uint8_t dest[6]; uint8_t ttl; + uint8_t align; + uint8_t dest[6]; uint8_t flags; + uint8_t align; uint8_t orig[6]; uint16_t seqno; } __packed;
On Saturday 28 May 2011 00:10:22 Antonio Quartulli wrote:
Move the ttl field to the third position of unicast_packet and unicast_frag_packet. In this way it possible to give them a better shape for later usage
Signed-off-by: Antonio Quartulli ordex@autistici.org
[..]
struct unicast_frag_packet { uint8_t packet_type; uint8_t version; /* batman version field */
- uint8_t dest[6]; uint8_t ttl;
- uint8_t align;
- uint8_t dest[6]; uint8_t flags;
- uint8_t align; uint8_t orig[6]; uint16_t seqno;
} __packed;
Wait a second - are there two "align" in a single struct. Sry, have to Nack that one :)
Kind regards, Sven
On Saturday 28 May 2011 00:20:21 Sven Eckelmann wrote:
struct unicast_frag_packet { uint8_t packet_type; uint8_t version; /* batman version field */
uint8_t dest[6]; uint8_t ttl;
uint8_t align;uint8_t dest[6]; uint8_t flags;uint8_t align; uint8_t orig[6]; uint16_t seqno;} __packed;
Wait a second - are there two "align" in a single struct. Sry, have to Nack that one :)
Yes, I suggested that because the tt patches will replace the first align with the ttvn field.
Cheers, Marek
Marek Lindner wrote:
On Saturday 28 May 2011 00:20:21 Sven Eckelmann wrote:
struct unicast_frag_packet {
uint8_t packet_type; uint8_t version; /* batman version field */
uint8_t dest[6]; uint8_t ttl;
uint8_t align;uint8_t dest[6]; uint8_t flags;uint8_t align; uint8_t orig[6]; uint16_t seqno;} __packed;
Wait a second - are there two "align" in a single struct. Sry, have to Nack that one :)
Yes, I suggested that because the tt patches will replace the first align with the ttvn field.
But it doesn't compile. I cannot forward stuff which is too broken. And personally I don't care who suggested it when my builtin c-parser explodes.
Ok, now I did the "work" to apply and and to compile that stuff to prove my point. Here are the slightly shortened results (gcc-4.6 from sid):
CC [M] aggregation.o In file included from types.h:27:0, from main.h:121, from aggregation.c:22: packet.h:114:11: error: duplicate member ‘align’ make[2]: *** [aggregation.o] Error 1 make[1]: *** [_module_/batman-adv] Error 2 make[1]: Leaving directory `linux-2.6.39' make: *** [all] Error 2
My suggestion: Rename the first align in every packet structure to 'reserved'.
Then to the next part which I don't like: the patch forgot to touch batman_packet, icmp_packet, icmp_packet_rr, bcast_packet and vis_packet. It doesn't make sense to patch half of the on-wire types to reduce the number of COMPAT_VERSIONs.
Kind regards, Sven
From: Antonio Quartulli ordex@autistici.org
The amount of duplicated code in the receive and routing code can be reduced when all headers provide the packet type, version and ttl in the same first bytes.
Signed-off-by: Antonio Quartulli ordex@autistici.org --- just my suggestion
packet.h | 21 ++++++++++++++------- 1 files changed, 14 insertions(+), 7 deletions(-)
diff --git a/packet.h b/packet.h index eda9965..c84f325 100644 --- a/packet.h +++ b/packet.h @@ -32,7 +32,7 @@ #define BAT_UNICAST_FRAG 0x06
/* this file is included by batctl which needs these defines */ -#define COMPAT_VERSION 12 +#define COMPAT_VERSION 14 #define DIRECTLINK 0x40 #define VIS_SERVER 0x20 #define PRIMARIES_FIRST_HOP 0x10 @@ -55,12 +55,13 @@ struct batman_packet { uint8_t packet_type; uint8_t version; /* batman version field */ + uint8_t ttl; + uint8_t reserved; uint8_t flags; /* 0x40: DIRECTLINK flag, 0x20 VIS_SERVER flag... */ uint8_t tq; uint32_t seqno; uint8_t orig[6]; uint8_t prev_sender[6]; - uint8_t ttl; uint8_t num_tt; uint8_t gw_flags; /* flags related to gateway class */ uint8_t align; @@ -71,8 +72,9 @@ struct batman_packet { struct icmp_packet { uint8_t packet_type; uint8_t version; /* batman version field */ - uint8_t msg_type; /* see ICMP message types above */ uint8_t ttl; + uint8_t reserved; + uint8_t msg_type; /* see ICMP message types above */ uint8_t dst[6]; uint8_t orig[6]; uint16_t seqno; @@ -86,8 +88,9 @@ struct icmp_packet { struct icmp_packet_rr { uint8_t packet_type; uint8_t version; /* batman version field */ - uint8_t msg_type; /* see ICMP message types above */ uint8_t ttl; + uint8_t reserved; + uint8_t msg_type; /* see ICMP message types above */ uint8_t dst[6]; uint8_t orig[6]; uint16_t seqno; @@ -99,16 +102,19 @@ struct icmp_packet_rr { struct unicast_packet { uint8_t packet_type; uint8_t version; /* batman version field */ - uint8_t dest[6]; uint8_t ttl; + uint8_t reserved; + uint8_t dest[6]; } __packed;
struct unicast_frag_packet { uint8_t packet_type; uint8_t version; /* batman version field */ - uint8_t dest[6]; uint8_t ttl; + uint8_t reserved; + uint8_t dest[6]; uint8_t flags; + uint8_t align; uint8_t orig[6]; uint16_t seqno; } __packed; @@ -116,8 +122,9 @@ struct unicast_frag_packet { struct bcast_packet { uint8_t packet_type; uint8_t version; /* batman version field */ - uint8_t orig[6]; uint8_t ttl; + uint8_t reserved; + uint8_t orig[6]; uint32_t seqno; } __packed;
From: Antonio Quartulli ordex@autistici.org
The amount of duplicated code in the receive and routing code can be reduced when all headers provide the packet type, version and ttl in the same first bytes.
Signed-off-by: Antonio Quartulli ordex@autistici.org --- * Only the first 3 bytes have to be the same. * vis_packet was not changed yet.
packet.h | 30 ++++++++++++++++++------------ 1 files changed, 18 insertions(+), 12 deletions(-)
diff --git a/packet.h b/packet.h index eda9965..36a3aad 100644 --- a/packet.h +++ b/packet.h @@ -32,7 +32,7 @@ #define BAT_UNICAST_FRAG 0x06
/* this file is included by batctl which needs these defines */ -#define COMPAT_VERSION 12 +#define COMPAT_VERSION 14 #define DIRECTLINK 0x40 #define VIS_SERVER 0x20 #define PRIMARIES_FIRST_HOP 0x10 @@ -55,15 +55,15 @@ struct batman_packet { uint8_t packet_type; uint8_t version; /* batman version field */ + uint8_t ttl; uint8_t flags; /* 0x40: DIRECTLINK flag, 0x20 VIS_SERVER flag... */ - uint8_t tq; uint32_t seqno; uint8_t orig[6]; uint8_t prev_sender[6]; - uint8_t ttl; - uint8_t num_tt; uint8_t gw_flags; /* flags related to gateway class */ - uint8_t align; + uint8_t tq; + uint8_t num_tt; + uint8_t reserved; } __packed;
#define BAT_PACKET_LEN sizeof(struct batman_packet) @@ -71,12 +71,13 @@ struct batman_packet { struct icmp_packet { uint8_t packet_type; uint8_t version; /* batman version field */ - uint8_t msg_type; /* see ICMP message types above */ uint8_t ttl; + uint8_t msg_type; /* see ICMP message types above */ uint8_t dst[6]; uint8_t orig[6]; uint16_t seqno; uint8_t uid; + uint8_t reserved; } __packed;
#define BAT_RR_LEN 16 @@ -86,8 +87,8 @@ struct icmp_packet { struct icmp_packet_rr { uint8_t packet_type; uint8_t version; /* batman version field */ - uint8_t msg_type; /* see ICMP message types above */ uint8_t ttl; + uint8_t msg_type; /* see ICMP message types above */ uint8_t dst[6]; uint8_t orig[6]; uint16_t seqno; @@ -99,16 +100,19 @@ struct icmp_packet_rr { struct unicast_packet { uint8_t packet_type; uint8_t version; /* batman version field */ - uint8_t dest[6]; uint8_t ttl; + uint8_t reserved; + uint8_t dest[6]; } __packed;
struct unicast_frag_packet { uint8_t packet_type; uint8_t version; /* batman version field */ - uint8_t dest[6]; uint8_t ttl; + uint8_t reserved; + uint8_t dest[6]; uint8_t flags; + uint8_t align; uint8_t orig[6]; uint16_t seqno; } __packed; @@ -116,18 +120,20 @@ struct unicast_frag_packet { struct bcast_packet { uint8_t packet_type; uint8_t version; /* batman version field */ - uint8_t orig[6]; uint8_t ttl; + uint8_t reserved; + uint8_t orig[6]; uint32_t seqno; } __packed;
struct vis_packet { uint8_t packet_type; uint8_t version; /* batman version field */ + uint8_t ttl; /* TTL */ uint8_t vis_type; /* which type of vis-participant sent this? */ - uint8_t entries; /* number of entries behind this struct */ uint32_t seqno; /* sequence number */ - uint8_t ttl; /* TTL */ + uint8_t entries; /* number of entries behind this struct */ + uint8_t reserved; uint8_t vis_orig[6]; /* originator that announces its neighbors */ uint8_t target_orig[6]; /* who should receive this packet */ uint8_t sender_orig[6]; /* who sent or rebroadcasted this packet */
On Saturday 28 May 2011 13:45:29 Marek Lindner wrote:
@@ -99,16 +100,19 @@ struct icmp_packet_rr { struct unicast_packet { uint8_t packet_type; uint8_t version; /* batman version field */
- uint8_t dest[6]; uint8_t ttl;
- uint8_t reserved;
- uint8_t dest[6];
} __packed;
struct unicast_frag_packet { uint8_t packet_type; uint8_t version; /* batman version field */
- uint8_t dest[6]; uint8_t ttl;
- uint8_t reserved;
- uint8_t dest[6]; uint8_t flags;
- uint8_t align; uint8_t orig[6]; uint16_t seqno;
} __packed;
Why dont you use the reserverd part for the flags which are currently not in unicast? Then you could also remove that other align byte. It would still be possible to add flags to unicast packets when necessary.
@@ -116,18 +120,20 @@ struct unicast_frag_packet { struct bcast_packet { uint8_t packet_type; uint8_t version; /* batman version field */
- uint8_t orig[6]; uint8_t ttl;
- uint8_t reserved;
- uint8_t orig[6]; uint32_t seqno;
} __packed;
Wouldn't that lead to an unaligned seqno?
Kind regards, Sven
On Saturday 28 May 2011 14:07:10 Sven Eckelmann wrote:
Why dont you use the reserverd part for the flags which are currently not in unicast? Then you could also remove that other align byte. It would still be possible to add flags to unicast packets when necessary.
The unicast_frag header assumes it looks like the unicast header plus some extra fields:
struct unicast_frag_packet { struct unicast_packet unicast_packet; uint8_t flags; uint8_t align; uint8_t orig[6]; uint16_t seqno; };
We probably should add a little comment there to make that clear.
Both reserved fields (unicast + unicast frag) are going to be converted to ttvn with the tt patches.
uint8_t reserved;
uint8_t orig[6];
uint32_t seqno;
} __packed;
Wouldn't that lead to an unaligned seqno?
Yes, I overlooked that the seqno is 32bit wide.
Regards, Marek
On Saturday 28 May 2011 14:17:14 Marek Lindner wrote:
On Saturday 28 May 2011 14:07:10 Sven Eckelmann wrote:
Why dont you use the reserverd part for the flags which are currently not in unicast? Then you could also remove that other align byte. It would still be possible to add flags to unicast packets when necessary.
The unicast_frag header assumes it looks like the unicast header plus some extra fields:
Where does it assume that the frag is _not_ part of the unicast_packet header?
struct unicast_frag_packet { struct unicast_packet unicast_packet; uint8_t flags; uint8_t align; uint8_t orig[6]; uint16_t seqno; };
We probably should add a little comment there to make that clear.
Both reserved fields (unicast + unicast frag) are going to be converted to ttvn with the tt patches.
Ok, makes sense to use reserve fields then
Kind regards, Sven
From: Antonio Quartulli ordex@autistici.org
The amount of duplicated code in the receive and routing code can be reduced when all headers provide the packet type, version and ttl in the same first bytes.
Signed-off-by: Antonio Quartulli ordex@autistici.org --- * Keep the reserved fields in unicast_frag_packet for ordex's changes
packet.h | 30 ++++++++++++++++++------------ 1 files changed, 18 insertions(+), 12 deletions(-)
diff --git a/packet.h b/packet.h index eda9965..f4052f2 100644 --- a/packet.h +++ b/packet.h @@ -32,7 +32,7 @@ #define BAT_UNICAST_FRAG 0x06
/* this file is included by batctl which needs these defines */ -#define COMPAT_VERSION 12 +#define COMPAT_VERSION 14 #define DIRECTLINK 0x40 #define VIS_SERVER 0x20 #define PRIMARIES_FIRST_HOP 0x10 @@ -55,15 +55,15 @@ struct batman_packet { uint8_t packet_type; uint8_t version; /* batman version field */ + uint8_t ttl; uint8_t flags; /* 0x40: DIRECTLINK flag, 0x20 VIS_SERVER flag... */ - uint8_t tq; uint32_t seqno; uint8_t orig[6]; uint8_t prev_sender[6]; - uint8_t ttl; - uint8_t num_tt; uint8_t gw_flags; /* flags related to gateway class */ - uint8_t align; + uint8_t tq; + uint8_t num_tt; + uint8_t reserved; } __packed;
#define BAT_PACKET_LEN sizeof(struct batman_packet) @@ -71,12 +71,13 @@ struct batman_packet { struct icmp_packet { uint8_t packet_type; uint8_t version; /* batman version field */ - uint8_t msg_type; /* see ICMP message types above */ uint8_t ttl; + uint8_t msg_type; /* see ICMP message types above */ uint8_t dst[6]; uint8_t orig[6]; uint16_t seqno; uint8_t uid; + uint8_t reserved; } __packed;
#define BAT_RR_LEN 16 @@ -86,8 +87,8 @@ struct icmp_packet { struct icmp_packet_rr { uint8_t packet_type; uint8_t version; /* batman version field */ - uint8_t msg_type; /* see ICMP message types above */ uint8_t ttl; + uint8_t msg_type; /* see ICMP message types above */ uint8_t dst[6]; uint8_t orig[6]; uint16_t seqno; @@ -99,16 +100,19 @@ struct icmp_packet_rr { struct unicast_packet { uint8_t packet_type; uint8_t version; /* batman version field */ - uint8_t dest[6]; uint8_t ttl; + uint8_t reserved; + uint8_t dest[6]; } __packed;
struct unicast_frag_packet { uint8_t packet_type; uint8_t version; /* batman version field */ - uint8_t dest[6]; uint8_t ttl; + uint8_t reserved; + uint8_t dest[6]; uint8_t flags; + uint8_t align; uint8_t orig[6]; uint16_t seqno; } __packed; @@ -116,18 +120,20 @@ struct unicast_frag_packet { struct bcast_packet { uint8_t packet_type; uint8_t version; /* batman version field */ - uint8_t orig[6]; uint8_t ttl; + uint8_t reserved; uint32_t seqno; + uint8_t orig[6]; } __packed;
struct vis_packet { uint8_t packet_type; uint8_t version; /* batman version field */ + uint8_t ttl; /* TTL */ uint8_t vis_type; /* which type of vis-participant sent this? */ - uint8_t entries; /* number of entries behind this struct */ uint32_t seqno; /* sequence number */ - uint8_t ttl; /* TTL */ + uint8_t entries; /* number of entries behind this struct */ + uint8_t reserved; uint8_t vis_orig[6]; /* originator that announces its neighbors */ uint8_t target_orig[6]; /* who should receive this packet */ uint8_t sender_orig[6]; /* who sent or rebroadcasted this packet */
On Saturday 28 May 2011 14:51:06 Sven Eckelmann wrote:
From: Antonio Quartulli ordex@autistici.org
The amount of duplicated code in the receive and routing code can be reduced when all headers provide the packet type, version and ttl in the same first bytes.
Applied in revision c7fb529.
Thanks, Marek
On Saturday 28 May 2011 10:43:03 Sven Eckelmann wrote:
From: Antonio Quartulli ordex@autistici.org
The amount of duplicated code in the receive and routing code can be reduced when all headers provide the packet type, version and ttl in the same first bytes.
Signed-off-by: Antonio Quartulli ordex@autistici.org
just my suggestion
Hm, forgot vis_packet and the 4 byte header is ugly. Maybe reordering everything is better....
Kind regards, Sven
From: Antonio Quartulli ordex@autistici.org
The amount of duplicated code in the receive and routing code can be reduced when all headers provide the packet type, version and ttl in the same first bytes.
Signed-off-by: Antonio Quartulli ordex@autistici.org --- * reduce to 3 bytes, but still keep alignments * corrected vis_packet
packet.h | 28 ++++++++++++++++------------ 1 files changed, 16 insertions(+), 12 deletions(-)
diff --git a/packet.h b/packet.h index eda9965..ede441b 100644 --- a/packet.h +++ b/packet.h @@ -32,7 +32,7 @@ #define BAT_UNICAST_FRAG 0x06
/* this file is included by batctl which needs these defines */ -#define COMPAT_VERSION 12 +#define COMPAT_VERSION 14 #define DIRECTLINK 0x40 #define VIS_SERVER 0x20 #define PRIMARIES_FIRST_HOP 0x10 @@ -55,15 +55,15 @@ struct batman_packet { uint8_t packet_type; uint8_t version; /* batman version field */ + uint8_t ttl; uint8_t flags; /* 0x40: DIRECTLINK flag, 0x20 VIS_SERVER flag... */ - uint8_t tq; uint32_t seqno; uint8_t orig[6]; uint8_t prev_sender[6]; - uint8_t ttl; - uint8_t num_tt; uint8_t gw_flags; /* flags related to gateway class */ - uint8_t align; + uint8_t tq; + uint8_t num_tt; + uint8_t reserved; } __packed;
#define BAT_PACKET_LEN sizeof(struct batman_packet) @@ -71,12 +71,13 @@ struct batman_packet { struct icmp_packet { uint8_t packet_type; uint8_t version; /* batman version field */ - uint8_t msg_type; /* see ICMP message types above */ uint8_t ttl; + uint8_t msg_type; /* see ICMP message types above */ uint8_t dst[6]; uint8_t orig[6]; uint16_t seqno; uint8_t uid; + uint8_t reserved; } __packed;
#define BAT_RR_LEN 16 @@ -86,8 +87,8 @@ struct icmp_packet { struct icmp_packet_rr { uint8_t packet_type; uint8_t version; /* batman version field */ - uint8_t msg_type; /* see ICMP message types above */ uint8_t ttl; + uint8_t msg_type; /* see ICMP message types above */ uint8_t dst[6]; uint8_t orig[6]; uint16_t seqno; @@ -99,16 +100,17 @@ struct icmp_packet_rr { struct unicast_packet { uint8_t packet_type; uint8_t version; /* batman version field */ - uint8_t dest[6]; uint8_t ttl; + uint8_t reserved; + uint8_t dest[6]; } __packed;
struct unicast_frag_packet { uint8_t packet_type; uint8_t version; /* batman version field */ - uint8_t dest[6]; uint8_t ttl; uint8_t flags; + uint8_t dest[6]; uint8_t orig[6]; uint16_t seqno; } __packed; @@ -116,18 +118,20 @@ struct unicast_frag_packet { struct bcast_packet { uint8_t packet_type; uint8_t version; /* batman version field */ - uint8_t orig[6]; uint8_t ttl; + uint8_t reserved; uint32_t seqno; + uint8_t orig[6]; } __packed;
struct vis_packet { uint8_t packet_type; uint8_t version; /* batman version field */ + uint8_t ttl; /* TTL */ uint8_t vis_type; /* which type of vis-participant sent this? */ - uint8_t entries; /* number of entries behind this struct */ uint32_t seqno; /* sequence number */ - uint8_t ttl; /* TTL */ + uint8_t entries; /* number of entries behind this struct */ + uint8_t reserved; uint8_t vis_orig[6]; /* originator that announces its neighbors */ uint8_t target_orig[6]; /* who should receive this packet */ uint8_t sender_orig[6]; /* who sent or rebroadcasted this packet */
On Saturday 28 May 2011 09:26:30 Sven Eckelmann wrote:
Yes, I suggested that because the tt patches will replace the first align with the ttvn field.
But it doesn't compile. I cannot forward stuff which is too broken. And personally I don't care who suggested it when my builtin c-parser explodes.
You got a point here. :-)
My suggestion: Rename the first align in every packet structure to 'reserved'.
Ok.
Then to the next part which I don't like: the patch forgot to touch batman_packet, icmp_packet, icmp_packet_rr, bcast_packet and vis_packet. It doesn't make sense to patch half of the on-wire types to reduce the number of COMPAT_VERSIONs.
If we touch every packet definition we also have to ensure that the code touching these packets does not implicitly assume certain positions (like route_unicast_packet() does).
Regards, Marek
b.a.t.m.a.n@lists.open-mesh.org
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Antonio Quartulli -
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Sven Eckelmann