mirror/xdp-project-bpf-examples
1
0
Fork 0
mirror of https://github.com/xdp-project/bpf-examples.git synced 2024-05-06 15:54:53 +00:00
Code Issues Projects Releases Wiki Activity

pping: Move some info from parsing_context to packet_info

Browse Source 
Remove the is_egress and ingress_ifindex from the parsing_context
struct to the packet_info struct. Also change the member is_egress to
is_ingress to better fit with the ingress_ifindex member.

These members were only in parsing_context because they were
convenient to fill in right from the start. However, it semantically
makes little sense for the parsing_context to contain these because
they are not used for any parsing, and they fit better with the
packet_info. This also allows later functions (is_local_address(),
pping_timestamp_packet() and pping_match_packet()) to get rid of their
dependency on parsing_context, as it was only used for the is_egress
and ingress_ifindex members (they do not do any parsing). After this
change, parsing_context is only used for the initial parsing, and
packet_info contains all the necessary data for all the functions
related to the pping logic that runs after the packet has been parsed.

Signed-off-by: Simon Sundberg <simon.sundberg@kau.se>
This commit is contained in:
Simon Sundberg
2022-05-31 21:19:19 +02:00
parent fc18074b31
commit aaf6036655
1 changed files with 17 additions and 21 deletions
Download Patch File Download Diff File Expand all files Collapse all files

38
pping/pping_kern.c
View File

@ -74,8 +74,6 @@ struct parsing_context {
void *data_end; // End of safe acessible area
struct hdr_cursor nh; // Position to parse next
__u32 pkt_len; // Full packet length (headers+data)
__u32 ingress_ifindex; // Interface packet arrived on
bool is_egress; // Is packet on egress or ingress?
};
/*
@ -103,6 +101,8 @@ struct packet_info {
__u32 payload; // Size of packet data (excluding headers)
struct packet_id pid; // flow + identifier to timestamp (ex. TSval)
struct packet_id reply_pid; // rev. flow + identifier to match against (ex. TSecr)
__u32 ingress_ifindex; // Interface packet arrived on (if is_ingress, otherwise not valid)
bool is_ingress; // Packet on egress or ingress?
bool pid_flow_is_dfkey; // Used to determine which member of dualflow state to use for forward direction
bool pid_valid; // identifier can be used to timestamp packet
bool reply_pid_valid; // reply_identifier can be used to match packet
@ -798,14 +798,13 @@ static void close_and_delete_flows(void *ctx, struct packet_info *p_info,
* samples/bpf/xdp_fwd_kern.c/xdp_fwd_flags() and
* tools/testing/selftests/bpf/progs/test_tc_neigh_fib.c
*/
static bool is_local_address(struct packet_info *p_info, void *ctx,
struct parsing_context *pctx)
static bool is_local_address(struct packet_info *p_info, void *ctx)
{
int ret;
struct bpf_fib_lookup lookup;
__builtin_memset(&lookup, 0, sizeof(lookup));
lookup.ifindex = pctx->ingress_ifindex;
lookup.ifindex = p_info->ingress_ifindex;
lookup.family = p_info->pid.flow.ipv;
if (lookup.family == AF_INET) {
@ -837,14 +836,13 @@ static bool is_local_address(struct packet_info *p_info, void *ctx,
* Attempt to create a timestamp-entry for packet p_info for flow in f_state
*/
static void pping_timestamp_packet(struct flow_state *f_state, void *ctx,
struct parsing_context *pctx,
struct packet_info *p_info, bool new_flow)
{
if (!is_flowstate_active(f_state) || !p_info->pid_valid)
return;
if (config.localfilt && !pctx->is_egress &&
is_local_address(p_info, ctx, pctx))
if (config.localfilt && p_info->is_ingress &&
is_local_address(p_info, ctx))
return;
// Check if identfier is new
@ -877,7 +875,6 @@ static void pping_timestamp_packet(struct flow_state *f_state, void *ctx,
* Attempt to match packet in p_info with a timestamp from flow in f_state
*/
static void pping_match_packet(struct flow_state *f_state, void *ctx,
struct parsing_context *pctx,
struct packet_info *p_info)
{
struct rtt_event re = { 0 };
@ -914,7 +911,7 @@ static void pping_match_packet(struct flow_state *f_state, void *ctx,
re.rec_pkts = f_state->rec_pkts;
re.rec_bytes = f_state->rec_bytes;
re.flow = p_info->pid.flow;
re.match_on_egress = pctx->is_egress;
re.match_on_egress = !p_info->is_ingress;
bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, &re, sizeof(re));
}
@ -922,7 +919,8 @@ static void pping_match_packet(struct flow_state *f_state, void *ctx,
* Will parse the ingress/egress packet in pctx and attempt to create a
* timestamp for it and match it against the reverse flow.
*/
static void pping(void *ctx, struct parsing_context *pctx)
static void pping(void *ctx, struct parsing_context *pctx, bool is_ingress,
__u32 ingress_ifindex)
{
struct packet_info p_info = { 0 };
struct dual_flow_state *df_state;
@ -932,17 +930,20 @@ static void pping(void *ctx, struct parsing_context *pctx)
if (parse_packet_identifier(pctx, &p_info) < 0)
return;
p_info.is_ingress = is_ingress;
p_info.ingress_ifindex = is_ingress ? ingress_ifindex : 0;
df_state = lookup_or_create_dualflow_state(ctx, &p_info, &new_flow);
if (!df_state)
return;
fw_flow = get_flowstate_from_packet(df_state, &p_info);
update_forward_flowstate(&p_info, fw_flow, &new_flow);
pping_timestamp_packet(fw_flow, ctx, pctx, &p_info, new_flow);
pping_timestamp_packet(fw_flow, ctx, &p_info, new_flow);
rev_flow = get_reverse_flowstate_from_packet(df_state, &p_info);
update_reverse_flowstate(ctx, &p_info, rev_flow);
pping_match_packet(rev_flow, ctx, pctx, &p_info);
pping_match_packet(rev_flow, ctx, &p_info);
close_and_delete_flows(ctx, &p_info, fw_flow, rev_flow);
}
@ -998,10 +999,9 @@ int pping_tc_egress(struct __sk_buff *skb)
.data_end = (void *)(long)skb->data_end,
.pkt_len = skb->len,
.nh = { .pos = pctx.data },
.is_egress = true,
};
pping(skb, &pctx);
pping(skb, &pctx, false, 0);
return TC_ACT_UNSPEC;
}
@ -1015,11 +1015,9 @@ int pping_tc_ingress(struct __sk_buff *skb)
.data_end = (void *)(long)skb->data_end,
.pkt_len = skb->len,
.nh = { .pos = pctx.data },
.ingress_ifindex = skb->ingress_ifindex,
.is_egress = false,
};
pping(skb, &pctx);
pping(skb, &pctx, true, skb->ingress_ifindex);
return TC_ACT_UNSPEC;
}
@ -1033,11 +1031,9 @@ int pping_xdp_ingress(struct xdp_md *ctx)
.data_end = (void *)(long)ctx->data_end,
.pkt_len = pctx.data_end - pctx.data,
.nh = { .pos = pctx.data },
.ingress_ifindex = ctx->ingress_ifindex,
.is_egress = false,
};
pping(ctx, &pctx);
pping(ctx, &pctx, true, ctx->ingress_ifindex);
return XDP_PASS;
}