Mercurial > hg > nginx
annotate src/event/quic/bpf/ngx_quic_reuseport_helper.c @ 9015:a2fbae359828 quic
QUIC: fixed indentation.
| author | Sergey Kandaurov <pluknet@nginx.com> |
|---|---|
| date | Wed, 16 Feb 2022 15:45:47 +0300 |
| parents | 1a489587e1c8 |
| children |
| rev | line source |
|---|---|
| 8676 | 1 #include <errno.h> |
| 2 #include <linux/string.h> | |
| 3 #include <linux/udp.h> | |
| 4 #include <linux/bpf.h> | |
| 5 /* | |
| 6 * the bpf_helpers.h is not included into linux-headers, only available | |
| 7 * with kernel sources in "tools/lib/bpf/bpf_helpers.h" or in libbpf. | |
| 8 */ | |
| 9 #include <bpf/bpf_helpers.h> | |
| 10 | |
| 11 | |
| 12 #if !defined(SEC) | |
| 13 #define SEC(NAME) __attribute__((section(NAME), used)) | |
| 14 #endif | |
| 15 | |
| 16 | |
| 17 #if defined(LICENSE_GPL) | |
| 18 | |
| 19 /* | |
| 20 * To see debug: | |
| 21 * | |
| 22 * echo 1 > /sys/kernel/debug/tracing/events/bpf_trace/enable | |
| 23 * cat /sys/kernel/debug/tracing/trace_pipe | |
| 24 * echo 0 > /sys/kernel/debug/tracing/events/bpf_trace/enable | |
| 25 */ | |
| 26 | |
| 27 #define debugmsg(fmt, ...) \ | |
| 28 do { \ | |
| 29 char __buf[] = fmt; \ | |
| 30 bpf_trace_printk(__buf, sizeof(__buf), ##__VA_ARGS__); \ | |
| 31 } while (0) | |
| 32 | |
| 33 #else | |
| 34 | |
| 35 #define debugmsg(fmt, ...) | |
| 36 | |
| 37 #endif | |
| 38 | |
| 39 char _license[] SEC("license") = LICENSE; | |
| 40 | |
| 41 /*****************************************************************************/ | |
| 42 | |
| 43 #define NGX_QUIC_PKT_LONG 0x80 /* header form */ | |
| 44 #define NGX_QUIC_SERVER_CID_LEN 20 | |
| 45 | |
| 46 | |
| 47 #define advance_data(nbytes) \ | |
| 48 offset += nbytes; \ | |
| 49 if (start + offset > end) { \ | |
| 50 debugmsg("cannot read %ld bytes at offset %ld", nbytes, offset); \ | |
| 51 goto failed; \ | |
| 52 } \ | |
| 53 data = start + offset - 1; | |
| 54 | |
| 55 | |
| 56 #define ngx_quic_parse_uint64(p) \ | |
| 57 (((__u64)(p)[0] << 56) | \ | |
| 58 ((__u64)(p)[1] << 48) | \ | |
| 59 ((__u64)(p)[2] << 40) | \ | |
| 60 ((__u64)(p)[3] << 32) | \ | |
|
8720
1a489587e1c8
QUIC: fixed key extraction in bpf.
Vladimir Homutov <vl@nginx.com>
parents:
8676
diff
changeset
|
61 ((__u64)(p)[4] << 24) | \ |
|
1a489587e1c8
QUIC: fixed key extraction in bpf.
Vladimir Homutov <vl@nginx.com>
parents:
8676
diff
changeset
|
62 ((__u64)(p)[5] << 16) | \ |
|
1a489587e1c8
QUIC: fixed key extraction in bpf.
Vladimir Homutov <vl@nginx.com>
parents:
8676
diff
changeset
|
63 ((__u64)(p)[6] << 8) | \ |
|
1a489587e1c8
QUIC: fixed key extraction in bpf.
Vladimir Homutov <vl@nginx.com>
parents:
8676
diff
changeset
|
64 ((__u64)(p)[7])) |
| 8676 | 65 |
| 66 /* | |
| 67 * actual map object is created by the "bpf" system call, | |
| 68 * all pointers to this variable are replaced by the bpf loader | |
| 69 */ | |
| 70 struct bpf_map_def SEC("maps") ngx_quic_sockmap; | |
| 71 | |
| 72 | |
| 73 SEC(PROGNAME) | |
| 74 int ngx_quic_select_socket_by_dcid(struct sk_reuseport_md *ctx) | |
| 75 { | |
| 76 int rc; | |
| 77 __u64 key; | |
| 78 size_t len, offset; | |
| 79 unsigned char *start, *end, *data, *dcid; | |
| 80 | |
| 81 start = ctx->data; | |
| 82 end = (unsigned char *) ctx->data_end; | |
| 83 offset = 0; | |
| 84 | |
|
8720
1a489587e1c8
QUIC: fixed key extraction in bpf.
Vladimir Homutov <vl@nginx.com>
parents:
8676
diff
changeset
|
85 advance_data(sizeof(struct udphdr)); /* data at UDP header */ |
|
1a489587e1c8
QUIC: fixed key extraction in bpf.
Vladimir Homutov <vl@nginx.com>
parents:
8676
diff
changeset
|
86 advance_data(1); /* data at QUIC flags */ |
| 8676 | 87 |
| 88 if (data[0] & NGX_QUIC_PKT_LONG) { | |
| 89 | |
|
8720
1a489587e1c8
QUIC: fixed key extraction in bpf.
Vladimir Homutov <vl@nginx.com>
parents:
8676
diff
changeset
|
90 advance_data(4); /* data at QUIC version */ |
|
1a489587e1c8
QUIC: fixed key extraction in bpf.
Vladimir Homutov <vl@nginx.com>
parents:
8676
diff
changeset
|
91 advance_data(1); /* data at DCID len */ |
|
1a489587e1c8
QUIC: fixed key extraction in bpf.
Vladimir Homutov <vl@nginx.com>
parents:
8676
diff
changeset
|
92 |
| 8676 | 93 len = data[0]; /* read DCID length */ |
| 94 | |
| 95 if (len < 8) { | |
| 96 /* it's useless to search for key in such short DCID */ | |
| 97 return SK_PASS; | |
| 98 } | |
| 99 | |
| 100 } else { | |
| 101 len = NGX_QUIC_SERVER_CID_LEN; | |
| 102 } | |
| 103 | |
| 104 dcid = &data[1]; | |
| 105 advance_data(len); /* we expect the packet to have full DCID */ | |
| 106 | |
| 107 /* make verifier happy */ | |
| 108 if (dcid + sizeof(__u64) > end) { | |
| 109 goto failed; | |
| 110 } | |
| 111 | |
| 112 key = ngx_quic_parse_uint64(dcid); | |
| 113 | |
| 114 rc = bpf_sk_select_reuseport(ctx, &ngx_quic_sockmap, &key, 0); | |
| 115 | |
| 116 switch (rc) { | |
| 117 case 0: | |
|
8720
1a489587e1c8
QUIC: fixed key extraction in bpf.
Vladimir Homutov <vl@nginx.com>
parents:
8676
diff
changeset
|
118 debugmsg("nginx quic socket selected by key 0x%llx", key); |
| 8676 | 119 return SK_PASS; |
| 120 | |
| 121 /* kernel returns positive error numbers, errno.h defines positive */ | |
| 122 case -ENOENT: | |
|
8720
1a489587e1c8
QUIC: fixed key extraction in bpf.
Vladimir Homutov <vl@nginx.com>
parents:
8676
diff
changeset
|
123 debugmsg("nginx quic default route for key 0x%llx", key); |
| 8676 | 124 /* let the default reuseport logic decide which socket to choose */ |
| 125 return SK_PASS; | |
| 126 | |
| 127 default: | |
|
8720
1a489587e1c8
QUIC: fixed key extraction in bpf.
Vladimir Homutov <vl@nginx.com>
parents:
8676
diff
changeset
|
128 debugmsg("nginx quic bpf_sk_select_reuseport err: %d key 0x%llx", |
|
9015
a2fbae359828
QUIC: fixed indentation.
Sergey Kandaurov <pluknet@nginx.com>
parents:
8720
diff
changeset
|
129 rc, key); |
| 8676 | 130 goto failed; |
| 131 } | |
| 132 | |
| 133 failed: | |
| 134 /* | |
| 135 * SK_DROP will generate ICMP, but we may want to process "invalid" packet | |
| 136 * in userspace quic to investigate further and finally react properly | |
| 137 * (maybe ignore, maybe send something in response or close connection) | |
| 138 */ | |
| 139 return SK_PASS; | |
| 140 } |