* egress otherwise). This is the only flag supported for now.
* Return
* **SK_PASS** on success, or **SK_DROP** on error.
+ *
+ * int bpf_lwt_push_encap(struct sk_buff *skb, u32 type, void *hdr, u32 len)
+ * Description
+ * Encapsulate the packet associated to *skb* within a Layer 3
+ * protocol header. This header is provided in the buffer at
+ * address *hdr*, with *len* its size in bytes. *type* indicates
+ * the protocol of the header and can be one of:
+ *
+ * **BPF_LWT_ENCAP_SEG6**
+ * IPv6 encapsulation with Segment Routing Header
+ * (**struct ipv6_sr_hdr**). *hdr* only contains the SRH,
+ * the IPv6 header is computed by the kernel.
+ * **BPF_LWT_ENCAP_SEG6_INLINE**
+ * Only works if *skb* contains an IPv6 packet. Insert a
+ * Segment Routing Header (**struct ipv6_sr_hdr**) inside
+ * the IPv6 header.
+ *
+ * A call to this helper is susceptible to change the underlaying
+ * packet buffer. Therefore, at load time, all checks on pointers
+ * previously done by the verifier are invalidated and must be
+ * performed again, if the helper is used in combination with
+ * direct packet access.
+ * Return
+ * 0 on success, or a negative error in case of failure.
+ *
+ * int bpf_lwt_seg6_store_bytes(struct sk_buff *skb, u32 offset, const void *from, u32 len)
+ * Description
+ * Store *len* bytes from address *from* into the packet
+ * associated to *skb*, at *offset*. Only the flags, tag and TLVs
+ * inside the outermost IPv6 Segment Routing Header can be
+ * modified through this helper.
+ *
+ * A call to this helper is susceptible to change the underlaying
+ * packet buffer. Therefore, at load time, all checks on pointers
+ * previously done by the verifier are invalidated and must be
+ * performed again, if the helper is used in combination with
+ * direct packet access.
+ * Return
+ * 0 on success, or a negative error in case of failure.
+ *
+ * int bpf_lwt_seg6_adjust_srh(struct sk_buff *skb, u32 offset, s32 delta)
+ * Description
+ * Adjust the size allocated to TLVs in the outermost IPv6
+ * Segment Routing Header contained in the packet associated to
+ * *skb*, at position *offset* by *delta* bytes. Only offsets
+ * after the segments are accepted. *delta* can be as well
+ * positive (growing) as negative (shrinking).
+ *
+ * A call to this helper is susceptible to change the underlaying
+ * packet buffer. Therefore, at load time, all checks on pointers
+ * previously done by the verifier are invalidated and must be
+ * performed again, if the helper is used in combination with
+ * direct packet access.
+ * Return
+ * 0 on success, or a negative error in case of failure.
+ *
+ * int bpf_lwt_seg6_action(struct sk_buff *skb, u32 action, void *param, u32 param_len)
+ * Description
+ * Apply an IPv6 Segment Routing action of type *action* to the
+ * packet associated to *skb*. Each action takes a parameter
+ * contained at address *param*, and of length *param_len* bytes.
+ * *action* can be one of:
+ *
+ * **SEG6_LOCAL_ACTION_END_X**
+ * End.X action: Endpoint with Layer-3 cross-connect.
+ * Type of *param*: **struct in6_addr**.
+ * **SEG6_LOCAL_ACTION_END_T**
+ * End.T action: Endpoint with specific IPv6 table lookup.
+ * Type of *param*: **int**.
+ * **SEG6_LOCAL_ACTION_END_B6**
+ * End.B6 action: Endpoint bound to an SRv6 policy.
+ * Type of param: **struct ipv6_sr_hdr**.
+ * **SEG6_LOCAL_ACTION_END_B6_ENCAP**
+ * End.B6.Encap action: Endpoint bound to an SRv6
+ * encapsulation policy.
+ * Type of param: **struct ipv6_sr_hdr**.
+ *
+ * A call to this helper is susceptible to change the underlaying
+ * packet buffer. Therefore, at load time, all checks on pointers
+ * previously done by the verifier are invalidated and must be
+ * performed again, if the helper is used in combination with
+ * direct packet access.
+ * Return
+ * 0 on success, or a negative error in case of failure.
*/
#define __BPF_FUNC_MAPPER(FN) \
FN(unspec), \
FN(fib_lookup), \
FN(sock_hash_update), \
FN(msg_redirect_hash), \
- FN(sk_redirect_hash),
+ FN(sk_redirect_hash), \
+ FN(lwt_push_encap), \
+ FN(lwt_seg6_store_bytes), \
+ FN(lwt_seg6_adjust_srh), \
+ FN(lwt_seg6_action),
/* integer value in 'imm' field of BPF_CALL instruction selects which helper
* function eBPF program intends to call
BPF_HDR_START_NET,
};
+/* Encapsulation type for BPF_FUNC_lwt_push_encap helper. */
+enum bpf_lwt_encap_mode {
+ BPF_LWT_ENCAP_SEG6,
+ BPF_LWT_ENCAP_SEG6_INLINE
+};
+
/* user accessible mirror of in-kernel sk_buff.
* new fields can only be added to the end of this structure
*/
#include <net/ip_fib.h>
#include <net/flow.h>
#include <net/arp.h>
+#include <net/ipv6.h>
+#include <linux/seg6_local.h>
+#include <net/seg6.h>
+#include <net/seg6_local.h>
/**
* sk_filter_trim_cap - run a packet through a socket filter
.arg3_type = ARG_ANYTHING,
};
-bool bpf_helper_changes_pkt_data(void *func)
-{
- if (func == bpf_skb_vlan_push ||
- func == bpf_skb_vlan_pop ||
- func == bpf_skb_store_bytes ||
- func == bpf_skb_change_proto ||
- func == bpf_skb_change_head ||
- func == bpf_skb_change_tail ||
- func == bpf_skb_adjust_room ||
- func == bpf_skb_pull_data ||
- func == bpf_clone_redirect ||
- func == bpf_l3_csum_replace ||
- func == bpf_l4_csum_replace ||
- func == bpf_xdp_adjust_head ||
- func == bpf_xdp_adjust_meta ||
- func == bpf_msg_pull_data ||
- func == bpf_xdp_adjust_tail)
- return true;
-
- return false;
-}
-
static unsigned long bpf_skb_copy(void *dst_buff, const void *skb,
unsigned long off, unsigned long len)
{
.arg4_type = ARG_ANYTHING,
};
+#if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
+static int bpf_push_seg6_encap(struct sk_buff *skb, u32 type, void *hdr, u32 len)
+{
+ int err;
+ struct ipv6_sr_hdr *srh = (struct ipv6_sr_hdr *)hdr;
+
+ if (!seg6_validate_srh(srh, len))
+ return -EINVAL;
+
+ switch (type) {
+ case BPF_LWT_ENCAP_SEG6_INLINE:
+ if (skb->protocol != htons(ETH_P_IPV6))
+ return -EBADMSG;
+
+ err = seg6_do_srh_inline(skb, srh);
+ break;
+ case BPF_LWT_ENCAP_SEG6:
+ skb_reset_inner_headers(skb);
+ skb->encapsulation = 1;
+ err = seg6_do_srh_encap(skb, srh, IPPROTO_IPV6);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ bpf_compute_data_pointers(skb);
+ if (err)
+ return err;
+
+ ipv6_hdr(skb)->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
+ skb_set_transport_header(skb, sizeof(struct ipv6hdr));
+
+ return seg6_lookup_nexthop(skb, NULL, 0);
+}
+#endif /* CONFIG_IPV6_SEG6_BPF */
+
+BPF_CALL_4(bpf_lwt_push_encap, struct sk_buff *, skb, u32, type, void *, hdr,
+ u32, len)
+{
+ switch (type) {
+#if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
+ case BPF_LWT_ENCAP_SEG6:
+ case BPF_LWT_ENCAP_SEG6_INLINE:
+ return bpf_push_seg6_encap(skb, type, hdr, len);
+#endif
+ default:
+ return -EINVAL;
+ }
+}
+
+static const struct bpf_func_proto bpf_lwt_push_encap_proto = {
+ .func = bpf_lwt_push_encap,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+ .arg2_type = ARG_ANYTHING,
+ .arg3_type = ARG_PTR_TO_MEM,
+ .arg4_type = ARG_CONST_SIZE
+};
+
+BPF_CALL_4(bpf_lwt_seg6_store_bytes, struct sk_buff *, skb, u32, offset,
+ const void *, from, u32, len)
+{
+#if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
+ struct seg6_bpf_srh_state *srh_state =
+ this_cpu_ptr(&seg6_bpf_srh_states);
+ void *srh_tlvs, *srh_end, *ptr;
+ struct ipv6_sr_hdr *srh;
+ int srhoff = 0;
+
+ if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0)
+ return -EINVAL;
+
+ srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
+ srh_tlvs = (void *)((char *)srh + ((srh->first_segment + 1) << 4));
+ srh_end = (void *)((char *)srh + sizeof(*srh) + srh_state->hdrlen);
+
+ ptr = skb->data + offset;
+ if (ptr >= srh_tlvs && ptr + len <= srh_end)
+ srh_state->valid = 0;
+ else if (ptr < (void *)&srh->flags ||
+ ptr + len > (void *)&srh->segments)
+ return -EFAULT;
+
+ if (unlikely(bpf_try_make_writable(skb, offset + len)))
+ return -EFAULT;
+
+ memcpy(skb->data + offset, from, len);
+ return 0;
+#else /* CONFIG_IPV6_SEG6_BPF */
+ return -EOPNOTSUPP;
+#endif
+}
+
+static const struct bpf_func_proto bpf_lwt_seg6_store_bytes_proto = {
+ .func = bpf_lwt_seg6_store_bytes,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+ .arg2_type = ARG_ANYTHING,
+ .arg3_type = ARG_PTR_TO_MEM,
+ .arg4_type = ARG_CONST_SIZE
+};
+
+BPF_CALL_4(bpf_lwt_seg6_action, struct sk_buff *, skb,
+ u32, action, void *, param, u32, param_len)
+{
+#if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
+ struct seg6_bpf_srh_state *srh_state =
+ this_cpu_ptr(&seg6_bpf_srh_states);
+ struct ipv6_sr_hdr *srh;
+ int srhoff = 0;
+ int err;
+
+ if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0)
+ return -EINVAL;
+ srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
+
+ if (!srh_state->valid) {
+ if (unlikely((srh_state->hdrlen & 7) != 0))
+ return -EBADMSG;
+
+ srh->hdrlen = (u8)(srh_state->hdrlen >> 3);
+ if (unlikely(!seg6_validate_srh(srh, (srh->hdrlen + 1) << 3)))
+ return -EBADMSG;
+
+ srh_state->valid = 1;
+ }
+
+ switch (action) {
+ case SEG6_LOCAL_ACTION_END_X:
+ if (param_len != sizeof(struct in6_addr))
+ return -EINVAL;
+ return seg6_lookup_nexthop(skb, (struct in6_addr *)param, 0);
+ case SEG6_LOCAL_ACTION_END_T:
+ if (param_len != sizeof(int))
+ return -EINVAL;
+ return seg6_lookup_nexthop(skb, NULL, *(int *)param);
+ case SEG6_LOCAL_ACTION_END_B6:
+ err = bpf_push_seg6_encap(skb, BPF_LWT_ENCAP_SEG6_INLINE,
+ param, param_len);
+ if (!err)
+ srh_state->hdrlen =
+ ((struct ipv6_sr_hdr *)param)->hdrlen << 3;
+ return err;
+ case SEG6_LOCAL_ACTION_END_B6_ENCAP:
+ err = bpf_push_seg6_encap(skb, BPF_LWT_ENCAP_SEG6,
+ param, param_len);
+ if (!err)
+ srh_state->hdrlen =
+ ((struct ipv6_sr_hdr *)param)->hdrlen << 3;
+ return err;
+ default:
+ return -EINVAL;
+ }
+#else /* CONFIG_IPV6_SEG6_BPF */
+ return -EOPNOTSUPP;
+#endif
+}
+
+static const struct bpf_func_proto bpf_lwt_seg6_action_proto = {
+ .func = bpf_lwt_seg6_action,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+ .arg2_type = ARG_ANYTHING,
+ .arg3_type = ARG_PTR_TO_MEM,
+ .arg4_type = ARG_CONST_SIZE
+};
+
+BPF_CALL_3(bpf_lwt_seg6_adjust_srh, struct sk_buff *, skb, u32, offset,
+ s32, len)
+{
+#if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
+ struct seg6_bpf_srh_state *srh_state =
+ this_cpu_ptr(&seg6_bpf_srh_states);
+ void *srh_end, *srh_tlvs, *ptr;
+ struct ipv6_sr_hdr *srh;
+ struct ipv6hdr *hdr;
+ int srhoff = 0;
+ int ret;
+
+ if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0)
+ return -EINVAL;
+ srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
+
+ srh_tlvs = (void *)((unsigned char *)srh + sizeof(*srh) +
+ ((srh->first_segment + 1) << 4));
+ srh_end = (void *)((unsigned char *)srh + sizeof(*srh) +
+ srh_state->hdrlen);
+ ptr = skb->data + offset;
+
+ if (unlikely(ptr < srh_tlvs || ptr > srh_end))
+ return -EFAULT;
+ if (unlikely(len < 0 && (void *)((char *)ptr - len) > srh_end))
+ return -EFAULT;
+
+ if (len > 0) {
+ ret = skb_cow_head(skb, len);
+ if (unlikely(ret < 0))
+ return ret;
+
+ ret = bpf_skb_net_hdr_push(skb, offset, len);
+ } else {
+ ret = bpf_skb_net_hdr_pop(skb, offset, -1 * len);
+ }
+
+ bpf_compute_data_pointers(skb);
+ if (unlikely(ret < 0))
+ return ret;
+
+ hdr = (struct ipv6hdr *)skb->data;
+ hdr->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
+
+ srh_state->hdrlen += len;
+ srh_state->valid = 0;
+ return 0;
+#else /* CONFIG_IPV6_SEG6_BPF */
+ return -EOPNOTSUPP;
+#endif
+}
+
+static const struct bpf_func_proto bpf_lwt_seg6_adjust_srh_proto = {
+ .func = bpf_lwt_seg6_adjust_srh,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+ .arg2_type = ARG_ANYTHING,
+ .arg3_type = ARG_ANYTHING,
+};
+
+bool bpf_helper_changes_pkt_data(void *func)
+{
+ if (func == bpf_skb_vlan_push ||
+ func == bpf_skb_vlan_pop ||
+ func == bpf_skb_store_bytes ||
+ func == bpf_skb_change_proto ||
+ func == bpf_skb_change_head ||
+ func == bpf_skb_change_tail ||
+ func == bpf_skb_adjust_room ||
+ func == bpf_skb_pull_data ||
+ func == bpf_clone_redirect ||
+ func == bpf_l3_csum_replace ||
+ func == bpf_l4_csum_replace ||
+ func == bpf_xdp_adjust_head ||
+ func == bpf_xdp_adjust_meta ||
+ func == bpf_msg_pull_data ||
+ func == bpf_xdp_adjust_tail ||
+ func == bpf_lwt_push_encap ||
+ func == bpf_lwt_seg6_store_bytes ||
+ func == bpf_lwt_seg6_adjust_srh ||
+ func == bpf_lwt_seg6_action
+ )
+ return true;
+
+ return false;
+}
+
static const struct bpf_func_proto *
bpf_base_func_proto(enum bpf_func_id func_id)
{
return bpf_skb_is_valid_access(off, size, type, prog, info);
}
-
/* Attach type specific accesses */
static bool __sock_filter_check_attach_type(int off,
enum bpf_access_type access_type,
projects / mirror_ubuntu-disco-kernel.git / commitdiff