diff options
Diffstat (limited to 'tools/testing/selftests/bpf/progs/test_xdp_meta.c')
| -rw-r--r-- | tools/testing/selftests/bpf/progs/test_xdp_meta.c | 386 |
1 files changed, 282 insertions, 104 deletions
diff --git a/tools/testing/selftests/bpf/progs/test_xdp_meta.c b/tools/testing/selftests/bpf/progs/test_xdp_meta.c index d79cb74b571e..0a0f371a2dec 100644 --- a/tools/testing/selftests/bpf/progs/test_xdp_meta.c +++ b/tools/testing/selftests/bpf/progs/test_xdp_meta.c @@ -4,6 +4,7 @@ #include <linux/if_ether.h> #include <linux/pkt_cls.h> +#include <bpf/bpf_endian.h> #include <bpf/bpf_helpers.h> #include "bpf_kfuncs.h" @@ -11,37 +12,72 @@ #define ctx_ptr(ctx, mem) (void *)(unsigned long)ctx->mem -/* Demonstrates how metadata can be passed from an XDP program to a TC program - * using bpf_xdp_adjust_meta. - * For the sake of testing the metadata support in drivers, the XDP program uses - * a fixed-size payload after the Ethernet header as metadata. The TC program - * copies the metadata it receives into a map so it can be checked from - * userspace. +/* Demonstrate passing metadata from XDP to TC using bpf_xdp_adjust_meta. + * + * The XDP program extracts a fixed-size payload following the Ethernet header + * and stores it as packet metadata to test the driver's metadata support. The + * TC program then verifies if the passed metadata is correct. */ -struct { - __uint(type, BPF_MAP_TYPE_ARRAY); - __uint(max_entries, 1); - __type(key, __u32); - __uint(value_size, META_SIZE); -} test_result SEC(".maps"); - bool test_pass; +static const __u8 smac_want[ETH_ALEN] = { + 0x12, 0x34, 0xDE, 0xAD, 0xBE, 0xEF, +}; + +static const __u8 meta_want[META_SIZE] = { + 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, + 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, + 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, + 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, +}; + +static bool check_smac(const struct ethhdr *eth) +{ + return !__builtin_memcmp(eth->h_source, smac_want, ETH_ALEN); +} + +static bool check_metadata(const char *file, int line, __u8 *meta_have) +{ + if (!__builtin_memcmp(meta_have, meta_want, META_SIZE)) + return true; + + bpf_stream_printk(BPF_STREAM_STDERR, + "FAIL:%s:%d: metadata mismatch\n" + " have:\n %pI6\n %pI6\n" + " want:\n %pI6\n %pI6\n", + file, line, + &meta_have[0x00], &meta_have[0x10], + &meta_want[0x00], &meta_want[0x10]); + return false; +} + +#define check_metadata(meta_have) check_metadata(__FILE__, __LINE__, meta_have) + +static bool check_skb_metadata(const char *file, int line, struct __sk_buff *skb) +{ + __u8 *data_meta = ctx_ptr(skb, data_meta); + __u8 *data = ctx_ptr(skb, data); + + return data_meta + META_SIZE <= data && (check_metadata)(file, line, data_meta); +} + +#define check_skb_metadata(skb) check_skb_metadata(__FILE__, __LINE__, skb) + SEC("tc") int ing_cls(struct __sk_buff *ctx) { - __u8 *data, *data_meta; - __u32 key = 0; - - data_meta = ctx_ptr(ctx, data_meta); - data = ctx_ptr(ctx, data); + __u8 *meta_have = ctx_ptr(ctx, data_meta); + __u8 *data = ctx_ptr(ctx, data); - if (data_meta + META_SIZE > data) - return TC_ACT_SHOT; + if (meta_have + META_SIZE > data) + goto out; - bpf_map_update_elem(&test_result, &key, data_meta, BPF_ANY); + if (!check_metadata(meta_have)) + goto out; + test_pass = true; +out: return TC_ACT_SHOT; } @@ -49,17 +85,17 @@ int ing_cls(struct __sk_buff *ctx) SEC("tc") int ing_cls_dynptr_read(struct __sk_buff *ctx) { + __u8 meta_have[META_SIZE]; struct bpf_dynptr meta; - const __u32 zero = 0; - __u8 *dst; - - dst = bpf_map_lookup_elem(&test_result, &zero); - if (!dst) - return TC_ACT_SHOT; bpf_dynptr_from_skb_meta(ctx, 0, &meta); - bpf_dynptr_read(dst, META_SIZE, &meta, 0, 0); + bpf_dynptr_read(meta_have, META_SIZE, &meta, 0, 0); + if (!check_metadata(meta_have)) + goto out; + + test_pass = true; +out: return TC_ACT_SHOT; } @@ -86,20 +122,18 @@ SEC("tc") int ing_cls_dynptr_slice(struct __sk_buff *ctx) { struct bpf_dynptr meta; - const __u32 zero = 0; - __u8 *dst, *src; - - dst = bpf_map_lookup_elem(&test_result, &zero); - if (!dst) - return TC_ACT_SHOT; + __u8 *meta_have; bpf_dynptr_from_skb_meta(ctx, 0, &meta); - src = bpf_dynptr_slice(&meta, 0, NULL, META_SIZE); - if (!src) - return TC_ACT_SHOT; + meta_have = bpf_dynptr_slice(&meta, 0, NULL, META_SIZE); + if (!meta_have) + goto out; - __builtin_memcpy(dst, src, META_SIZE); + if (!check_metadata(meta_have)) + goto out; + test_pass = true; +out: return TC_ACT_SHOT; } @@ -129,14 +163,12 @@ int ing_cls_dynptr_slice_rdwr(struct __sk_buff *ctx) SEC("tc") int ing_cls_dynptr_offset_rd(struct __sk_buff *ctx) { - struct bpf_dynptr meta; const __u32 chunk_len = META_SIZE / 4; - const __u32 zero = 0; + __u8 meta_have[META_SIZE]; + struct bpf_dynptr meta; __u8 *dst, *src; - dst = bpf_map_lookup_elem(&test_result, &zero); - if (!dst) - return TC_ACT_SHOT; + dst = meta_have; /* 1. Regular read */ bpf_dynptr_from_skb_meta(ctx, 0, &meta); @@ -155,9 +187,14 @@ int ing_cls_dynptr_offset_rd(struct __sk_buff *ctx) /* 4. Read from a slice starting at an offset */ src = bpf_dynptr_slice(&meta, 2 * chunk_len, NULL, chunk_len); if (!src) - return TC_ACT_SHOT; + goto out; __builtin_memcpy(dst, src, chunk_len); + if (!check_metadata(meta_have)) + goto out; + + test_pass = true; +out: return TC_ACT_SHOT; } @@ -254,7 +291,7 @@ int ing_xdp_zalloc_meta(struct xdp_md *ctx) /* Drop any non-test packets */ if (eth + 1 > ctx_ptr(ctx, data_end)) return XDP_DROP; - if (eth->h_proto != 0) + if (!check_smac(eth)) return XDP_DROP; ret = bpf_xdp_adjust_meta(ctx, -META_SIZE); @@ -294,9 +331,9 @@ int ing_xdp(struct xdp_md *ctx) /* The Linux networking stack may send other packets on the test * interface that interfere with the test. Just drop them. - * The test packets can be recognized by their ethertype of zero. + * The test packets can be recognized by their source MAC address. */ - if (eth->h_proto != 0) + if (!check_smac(eth)) return XDP_DROP; __builtin_memcpy(data_meta, payload, META_SIZE); @@ -304,22 +341,25 @@ int ing_xdp(struct xdp_md *ctx) } /* - * Check that skb->data_meta..skb->data is empty if prog writes to packet - * _payload_ using packet pointers. Applies only to cloned skbs. + * Check that, when operating on a cloned packet, skb->data_meta..skb->data is + * kept intact if prog writes to packet _payload_ using packet pointers. */ SEC("tc") -int clone_data_meta_empty_on_data_write(struct __sk_buff *ctx) +int clone_data_meta_survives_data_write(struct __sk_buff *ctx) { + __u8 *meta_have = ctx_ptr(ctx, data_meta); struct ethhdr *eth = ctx_ptr(ctx, data); if (eth + 1 > ctx_ptr(ctx, data_end)) goto out; /* Ignore non-test packets */ - if (eth->h_proto != 0) + if (!check_smac(eth)) + goto out; + + if (meta_have + META_SIZE > eth) goto out; - /* Expect no metadata */ - if (ctx->data_meta != ctx->data) + if (!check_metadata(meta_have)) goto out; /* Packet write to trigger unclone in prologue */ @@ -331,40 +371,44 @@ out: } /* - * Check that skb->data_meta..skb->data is empty if prog writes to packet - * _metadata_ using packet pointers. Applies only to cloned skbs. + * Check that, when operating on a cloned packet, skb->data_meta..skb->data is + * kept intact if prog writes to packet _metadata_ using packet pointers. */ SEC("tc") -int clone_data_meta_empty_on_meta_write(struct __sk_buff *ctx) +int clone_data_meta_survives_meta_write(struct __sk_buff *ctx) { + __u8 *meta_have = ctx_ptr(ctx, data_meta); struct ethhdr *eth = ctx_ptr(ctx, data); - __u8 *md = ctx_ptr(ctx, data_meta); if (eth + 1 > ctx_ptr(ctx, data_end)) goto out; /* Ignore non-test packets */ - if (eth->h_proto != 0) + if (!check_smac(eth)) goto out; - if (md + 1 > ctx_ptr(ctx, data)) { - /* Expect no metadata */ - test_pass = true; - } else { - /* Metadata write to trigger unclone in prologue */ - *md = 42; - } + if (meta_have + META_SIZE > eth) + goto out; + + if (!check_metadata(meta_have)) + goto out; + + /* Metadata write to trigger unclone in prologue */ + *meta_have = 42; + + test_pass = true; out: return TC_ACT_SHOT; } /* - * Check that skb_meta dynptr is writable but empty if prog writes to packet - * _payload_ using a dynptr slice. Applies only to cloned skbs. + * Check that, when operating on a cloned packet, metadata remains intact if + * prog creates a r/w slice to packet _payload_. */ SEC("tc") -int clone_dynptr_empty_on_data_slice_write(struct __sk_buff *ctx) +int clone_meta_dynptr_survives_data_slice_write(struct __sk_buff *ctx) { struct bpf_dynptr data, meta; + __u8 meta_have[META_SIZE]; struct ethhdr *eth; bpf_dynptr_from_skb(ctx, 0, &data); @@ -372,51 +416,45 @@ int clone_dynptr_empty_on_data_slice_write(struct __sk_buff *ctx) if (!eth) goto out; /* Ignore non-test packets */ - if (eth->h_proto != 0) + if (!check_smac(eth)) goto out; - /* Expect no metadata */ bpf_dynptr_from_skb_meta(ctx, 0, &meta); - if (bpf_dynptr_is_rdonly(&meta) || bpf_dynptr_size(&meta) > 0) + bpf_dynptr_read(meta_have, META_SIZE, &meta, 0, 0); + if (!check_metadata(meta_have)) goto out; - /* Packet write to trigger unclone in prologue */ - eth->h_proto = 42; - test_pass = true; out: return TC_ACT_SHOT; } /* - * Check that skb_meta dynptr is writable but empty if prog writes to packet - * _metadata_ using a dynptr slice. Applies only to cloned skbs. + * Check that, when operating on a cloned packet, metadata remains intact if + * prog creates an r/w slice to packet _metadata_. */ SEC("tc") -int clone_dynptr_empty_on_meta_slice_write(struct __sk_buff *ctx) +int clone_meta_dynptr_survives_meta_slice_write(struct __sk_buff *ctx) { struct bpf_dynptr data, meta; const struct ethhdr *eth; - __u8 *md; + __u8 *meta_have; bpf_dynptr_from_skb(ctx, 0, &data); eth = bpf_dynptr_slice(&data, 0, NULL, sizeof(*eth)); if (!eth) goto out; /* Ignore non-test packets */ - if (eth->h_proto != 0) + if (!check_smac(eth)) goto out; - /* Expect no metadata */ bpf_dynptr_from_skb_meta(ctx, 0, &meta); - if (bpf_dynptr_is_rdonly(&meta) || bpf_dynptr_size(&meta) > 0) + meta_have = bpf_dynptr_slice_rdwr(&meta, 0, NULL, META_SIZE); + if (!meta_have) goto out; - /* Metadata write to trigger unclone in prologue */ - bpf_dynptr_from_skb_meta(ctx, 0, &meta); - md = bpf_dynptr_slice_rdwr(&meta, 0, NULL, sizeof(*md)); - if (md) - *md = 42; + if (!check_metadata(meta_have)) + goto out; test_pass = true; out: @@ -424,34 +462,40 @@ out: } /* - * Check that skb_meta dynptr is read-only before prog writes to packet payload - * using dynptr_write helper. Applies only to cloned skbs. + * Check that, when operating on a cloned packet, skb_meta dynptr is read-write + * before prog writes to packet _payload_ using dynptr_write helper and metadata + * remains intact before and after the write. */ SEC("tc") -int clone_dynptr_rdonly_before_data_dynptr_write(struct __sk_buff *ctx) +int clone_meta_dynptr_rw_before_data_dynptr_write(struct __sk_buff *ctx) { struct bpf_dynptr data, meta; + __u8 meta_have[META_SIZE]; const struct ethhdr *eth; + int err; bpf_dynptr_from_skb(ctx, 0, &data); eth = bpf_dynptr_slice(&data, 0, NULL, sizeof(*eth)); if (!eth) goto out; /* Ignore non-test packets */ - if (eth->h_proto != 0) + if (!check_smac(eth)) goto out; - /* Expect read-only metadata before unclone */ + /* Expect read-write metadata before unclone */ bpf_dynptr_from_skb_meta(ctx, 0, &meta); - if (!bpf_dynptr_is_rdonly(&meta) || bpf_dynptr_size(&meta) != META_SIZE) + if (bpf_dynptr_is_rdonly(&meta)) + goto out; + + err = bpf_dynptr_read(meta_have, META_SIZE, &meta, 0, 0); + if (err || !check_metadata(meta_have)) goto out; /* Helper write to payload will unclone the packet */ bpf_dynptr_write(&data, offsetof(struct ethhdr, h_proto), "x", 1, 0); - /* Expect no metadata after unclone */ - bpf_dynptr_from_skb_meta(ctx, 0, &meta); - if (bpf_dynptr_is_rdonly(&meta) || bpf_dynptr_size(&meta) != 0) + err = bpf_dynptr_read(meta_have, META_SIZE, &meta, 0, 0); + if (err || !check_metadata(meta_have)) goto out; test_pass = true; @@ -460,31 +504,165 @@ out: } /* - * Check that skb_meta dynptr is read-only if prog writes to packet - * metadata using dynptr_write helper. Applies only to cloned skbs. + * Check that, when operating on a cloned packet, skb_meta dynptr is read-write + * before prog writes to packet _metadata_ using dynptr_write helper and + * metadata remains intact before and after the write. */ SEC("tc") -int clone_dynptr_rdonly_before_meta_dynptr_write(struct __sk_buff *ctx) +int clone_meta_dynptr_rw_before_meta_dynptr_write(struct __sk_buff *ctx) { struct bpf_dynptr data, meta; + __u8 meta_have[META_SIZE]; const struct ethhdr *eth; + int err; bpf_dynptr_from_skb(ctx, 0, &data); eth = bpf_dynptr_slice(&data, 0, NULL, sizeof(*eth)); if (!eth) goto out; /* Ignore non-test packets */ - if (eth->h_proto != 0) + if (!check_smac(eth)) goto out; - /* Expect read-only metadata */ + /* Expect read-write metadata before unclone */ bpf_dynptr_from_skb_meta(ctx, 0, &meta); - if (!bpf_dynptr_is_rdonly(&meta) || bpf_dynptr_size(&meta) != META_SIZE) + if (bpf_dynptr_is_rdonly(&meta)) goto out; - /* Metadata write. Expect failure. */ - bpf_dynptr_from_skb_meta(ctx, 0, &meta); - if (bpf_dynptr_write(&meta, 0, "x", 1, 0) != -EINVAL) + err = bpf_dynptr_read(meta_have, META_SIZE, &meta, 0, 0); + if (err || !check_metadata(meta_have)) + goto out; + + /* Helper write to metadata will unclone the packet */ + bpf_dynptr_write(&meta, 0, &meta_have[0], 1, 0); + + err = bpf_dynptr_read(meta_have, META_SIZE, &meta, 0, 0); + if (err || !check_metadata(meta_have)) + goto out; + + test_pass = true; +out: + return TC_ACT_SHOT; +} + +SEC("tc") +int helper_skb_vlan_push_pop(struct __sk_buff *ctx) +{ + int err; + + /* bpf_skb_vlan_push assumes HW offload for primary VLAN tag. Only + * secondary tag push triggers an actual MAC header modification. + */ + err = bpf_skb_vlan_push(ctx, 0, 42); + if (err) + goto out; + err = bpf_skb_vlan_push(ctx, 0, 207); + if (err) + goto out; + + if (!check_skb_metadata(ctx)) + goto out; + + err = bpf_skb_vlan_pop(ctx); + if (err) + goto out; + err = bpf_skb_vlan_pop(ctx); + if (err) + goto out; + + if (!check_skb_metadata(ctx)) + goto out; + + test_pass = true; +out: + return TC_ACT_SHOT; +} + +SEC("tc") +int helper_skb_adjust_room(struct __sk_buff *ctx) +{ + int err; + + /* Grow a 1 byte hole after the MAC header */ + err = bpf_skb_adjust_room(ctx, 1, BPF_ADJ_ROOM_MAC, 0); + if (err) + goto out; + + if (!check_skb_metadata(ctx)) + goto out; + + /* Shrink a 1 byte hole after the MAC header */ + err = bpf_skb_adjust_room(ctx, -1, BPF_ADJ_ROOM_MAC, 0); + if (err) + goto out; + + if (!check_skb_metadata(ctx)) + goto out; + + /* Grow a 256 byte hole to trigger head reallocation */ + err = bpf_skb_adjust_room(ctx, 256, BPF_ADJ_ROOM_MAC, 0); + if (err) + goto out; + + if (!check_skb_metadata(ctx)) + goto out; + + test_pass = true; +out: + return TC_ACT_SHOT; +} + +SEC("tc") +int helper_skb_change_head_tail(struct __sk_buff *ctx) +{ + int err; + + /* Reserve 1 extra in the front for packet data */ + err = bpf_skb_change_head(ctx, 1, 0); + if (err) + goto out; + + if (!check_skb_metadata(ctx)) + goto out; + + /* Reserve 256 extra bytes in the front to trigger head reallocation */ + err = bpf_skb_change_head(ctx, 256, 0); + if (err) + goto out; + + if (!check_skb_metadata(ctx)) + goto out; + + /* Reserve 4k extra bytes in the back to trigger head reallocation */ + err = bpf_skb_change_tail(ctx, ctx->len + 4096, 0); + if (err) + goto out; + + if (!check_skb_metadata(ctx)) + goto out; + + test_pass = true; +out: + return TC_ACT_SHOT; +} + +SEC("tc") +int helper_skb_change_proto(struct __sk_buff *ctx) +{ + int err; + + err = bpf_skb_change_proto(ctx, bpf_htons(ETH_P_IPV6), 0); + if (err) + goto out; + + if (!check_skb_metadata(ctx)) + goto out; + + err = bpf_skb_change_proto(ctx, bpf_htons(ETH_P_IP), 0); + if (err) + goto out; + + if (!check_skb_metadata(ctx)) goto out; test_pass = true; |