Merge pull request iovisor#634 from Eichhoernchen/xdp_net-next

Added XDP support to BCC

src/cc/compat/linux/bpf.h

@@ -84,6 +84,7 @@ enum bpf_map_type {
  BPF_MAP_TYPE_PERCPU_HASH,
  BPF_MAP_TYPE_PERCPU_ARRAY,
  BPF_MAP_TYPE_STACK_TRACE,
+ BPF_MAP_TYPE_CGROUP_ARRAY,
 };
 
 enum bpf_prog_type {
@@ -92,6 +93,8 @@ enum bpf_prog_type {
  BPF_PROG_TYPE_KPROBE,
  BPF_PROG_TYPE_SCHED_CLS,
  BPF_PROG_TYPE_SCHED_ACT,
+ BPF_PROG_TYPE_TRACEPOINT,
+ BPF_PROG_TYPE_XDP,
 };
 
 #define BPF_PSEUDO_MAP_FD 1
@@ -312,6 +315,66 @@ enum bpf_func_id {
  */
  BPF_FUNC_skb_get_tunnel_opt,
  BPF_FUNC_skb_set_tunnel_opt,
+
+ /**
+ * bpf_skb_change_proto(skb, proto, flags)
+ * Change protocol of the skb. Currently supported is
+ * v4 -> v6, v6 -> v4 transitions. The helper will also
+ * resize the skb. eBPF program is expected to fill the
+ * new headers via skb_store_bytes and lX_csum_replace.
+ * @skb: pointer to skb
+ * @proto: new skb->protocol type
+ * @flags: reserved
+ * Return: 0 on success or negative error
+ */
+ BPF_FUNC_skb_change_proto,
+
+ /**
+ * bpf_skb_change_type(skb, type)
+ * Change packet type of skb.
+ * @skb: pointer to skb
+ * @type: new skb->pkt_type type
+ * Return: 0 on success or negative error
+ */
+ BPF_FUNC_skb_change_type,
+
+ /**
+ * bpf_skb_in_cgroup(skb, map, index) - Check cgroup2 membership of skb
+ * @skb: pointer to skb
+ * @map: pointer to bpf_map in BPF_MAP_TYPE_CGROUP_ARRAY type
+ * @index: index of the cgroup in the bpf_map
+ * Return:
+ * == 0 skb failed the cgroup2 descendant test
+ * == 1 skb succeeded the cgroup2 descendant test
+ * < 0 error
+ */
+ BPF_FUNC_skb_in_cgroup,
+
+ /**
+ * bpf_get_hash_recalc(skb)
+ * Retrieve and possibly recalculate skb->hash.
+ * @skb: pointer to skb
+ * Return: hash
+ */
+ BPF_FUNC_get_hash_recalc,
+
+ /**
+ * u64 bpf_get_current_task(void)
+ * Returns current task_struct
+ * Return: current
+ */
+ BPF_FUNC_get_current_task,
+
+ /**
+ * bpf_probe_write_user(void *dst, void *src, int len)
+ * safely attempt to write to a location
+ * @dst: destination address in userspace
+ * @src: source address on stack
+ * @len: number of bytes to copy
+ * Return: 0 on success or negative error
+ */
+ BPF_FUNC_probe_write_user,
+
  __BPF_FUNC_MAX_ID,
 };
 
@@ -346,6 +409,12 @@ enum bpf_func_id {
 #define BPF_F_ZERO_CSUM_TX (1ULL << 1)
 #define BPF_F_DONT_FRAGMENT (1ULL << 2)
 
+/* BPF_FUNC_perf_event_output and BPF_FUNC_perf_event_read flags. */
+#define BPF_F_INDEX_MASK 0xffffffffULL
+#define BPF_F_CURRENT_CPU BPF_F_INDEX_MASK
+/* BPF_FUNC_perf_event_output for sk_buff input context. */
+#define BPF_F_CTXLEN_MASK (0xfffffULL << 32)
+
 /* user accessible mirror of in-kernel sk_buff.
  * new fields can only be added to the end of this structure
  */
@@ -365,6 +434,8 @@ struct __sk_buff {
  __u32 cb[5];
  __u32 hash;
  __u32 tc_classid;
+ __u32 data;
+ __u32 data_end;
 };
 
 struct bpf_tunnel_key {
@@ -379,4 +450,24 @@ struct bpf_tunnel_key {
  __u32 tunnel_label;
 };
 
+/* User return codes for XDP prog type.
+ * A valid XDP program must return one of these defined values. All other
+ * return codes are reserved for future use. Unknown return codes will result
+ * in packet drop.
+ */
+enum xdp_action {
+ XDP_ABORTED = 0,
+ XDP_DROP,
+ XDP_PASS,
+ XDP_TX,
+};
+
+/* user accessible metadata for XDP packet hook
+ * new fields must be added to the end of this structure
+ */
+struct xdp_md {
+ __u32 data;
+ __u32 data_end;
+};
+
 #endif /* _UAPI__LINUX_BPF_H__ */

src/cc/compat/linux/virtual_bpf.h

@@ -85,6 +85,7 @@ enum bpf_map_type {
  BPF_MAP_TYPE_PERCPU_HASH,
  BPF_MAP_TYPE_PERCPU_ARRAY,
  BPF_MAP_TYPE_STACK_TRACE,
+ BPF_MAP_TYPE_CGROUP_ARRAY,
 };
 
 enum bpf_prog_type {
@@ -93,6 +94,8 @@ enum bpf_prog_type {
  BPF_PROG_TYPE_KPROBE,
  BPF_PROG_TYPE_SCHED_CLS,
  BPF_PROG_TYPE_SCHED_ACT,
+ BPF_PROG_TYPE_TRACEPOINT,
+ BPF_PROG_TYPE_XDP,
 };
 
 #define BPF_PSEUDO_MAP_FD 1
@@ -313,6 +316,66 @@ enum bpf_func_id {
  */
  BPF_FUNC_skb_get_tunnel_opt,
  BPF_FUNC_skb_set_tunnel_opt,
+
+ /**
+ * bpf_skb_change_proto(skb, proto, flags)
+ * Change protocol of the skb. Currently supported is
+ * v4 -> v6, v6 -> v4 transitions. The helper will also
+ * resize the skb. eBPF program is expected to fill the
+ * new headers via skb_store_bytes and lX_csum_replace.
+ * @skb: pointer to skb
+ * @proto: new skb->protocol type
+ * @flags: reserved
+ * Return: 0 on success or negative error
+ */
+ BPF_FUNC_skb_change_proto,
+
+ /**
+ * bpf_skb_change_type(skb, type)
+ * Change packet type of skb.
+ * @skb: pointer to skb
+ * @type: new skb->pkt_type type
+ * Return: 0 on success or negative error
+ */
+ BPF_FUNC_skb_change_type,
+
+ /**
+ * bpf_skb_in_cgroup(skb, map, index) - Check cgroup2 membership of skb
+ * @skb: pointer to skb
+ * @map: pointer to bpf_map in BPF_MAP_TYPE_CGROUP_ARRAY type
+ * @index: index of the cgroup in the bpf_map
+ * Return:
+ * == 0 skb failed the cgroup2 descendant test
+ * == 1 skb succeeded the cgroup2 descendant test
+ * < 0 error
+ */
+ BPF_FUNC_skb_in_cgroup,
+
+ /**
+ * bpf_get_hash_recalc(skb)
+ * Retrieve and possibly recalculate skb->hash.
+ * @skb: pointer to skb
+ * Return: hash
+ */
+ BPF_FUNC_get_hash_recalc,
+
+ /**
+ * u64 bpf_get_current_task(void)
+ * Returns current task_struct
+ * Return: current
+ */
+ BPF_FUNC_get_current_task,
+
+ /**
+ * bpf_probe_write_user(void *dst, void *src, int len)
+ * safely attempt to write to a location
+ * @dst: destination address in userspace
+ * @src: source address on stack
+ * @len: number of bytes to copy
+ * Return: 0 on success or negative error
+ */
+ BPF_FUNC_probe_write_user,
+
  __BPF_FUNC_MAX_ID,
 };
 
@@ -347,6 +410,12 @@ enum bpf_func_id {
 #define BPF_F_ZERO_CSUM_TX (1ULL << 1)
 #define BPF_F_DONT_FRAGMENT (1ULL << 2)
 
+/* BPF_FUNC_perf_event_output and BPF_FUNC_perf_event_read flags. */
+#define BPF_F_INDEX_MASK 0xffffffffULL
+#define BPF_F_CURRENT_CPU BPF_F_INDEX_MASK
+/* BPF_FUNC_perf_event_output for sk_buff input context. */
+#define BPF_F_CTXLEN_MASK (0xfffffULL << 32)
+
 /* user accessible mirror of in-kernel sk_buff.
  * new fields can only be added to the end of this structure
  */
@@ -366,6 +435,8 @@ struct __sk_buff {
  __u32 cb[5];
  __u32 hash;
  __u32 tc_classid;
+ __u32 data;
+ __u32 data_end;
 };
 
 struct bpf_tunnel_key {
@@ -380,5 +451,25 @@ struct bpf_tunnel_key {
  __u32 tunnel_label;
 };
 
+/* User return codes for XDP prog type.
+ * A valid XDP program must return one of these defined values. All other
+ * return codes are reserved for future use. Unknown return codes will result
+ * in packet drop.
+ */
+enum xdp_action {
+ XDP_ABORTED = 0,
+ XDP_DROP,
+ XDP_PASS,
+ XDP_TX,
+};
+
+/* user accessible metadata for XDP packet hook
+ * new fields must be added to the end of this structure
+ */
+struct xdp_md {
+ __u32 data;
+ __u32 data_end;
+};
+
 #endif /* _UAPI__LINUX_BPF_H__ */
 )********"

src/cc/libbpf.c

@@ -408,3 +408,104 @@ void * bpf_open_perf_buffer(perf_reader_raw_cb raw_cb, void *cb_cookie, int pid,
 
  return NULL;
 }
+
+
+
+int bpf_attach_xdp(const char *dev_name, int progfd) {
+ struct sockaddr_nl sa;
+ int sock, seq = 0, len, ret = -1;
+ char buf[4096];
+ struct nlattr *nla, *nla_xdp;
+ struct {
+ struct nlmsghdr nh;
+ struct ifinfomsg ifinfo;
+ char attrbuf[64];
+ } req;
+ struct nlmsghdr *nh;
+ struct nlmsgerr *err;
+
+ memset(&sa, 0, sizeof(sa));
+ sa.nl_family = AF_NETLINK;
+
+ sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
+ if (sock < 0) {
+ fprintf(stderr, "bpf: opening a netlink socket: %s\n", strerror(errno));
+ return -1;
+ }
+
+ if (bind(sock, (struct sockaddr *)&sa, sizeof(sa)) < 0) {
+ fprintf(stderr, "bpf: bind to netlink: %s\n", strerror(errno));
+ goto cleanup;
+ }
+
+ memset(&req, 0, sizeof(req));
+ req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg));
+ req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK;
+ req.nh.nlmsg_type = RTM_SETLINK;
+ req.nh.nlmsg_pid = 0;
+ req.nh.nlmsg_seq = ++seq;
+ req.ifinfo.ifi_family = AF_UNSPEC;
+ req.ifinfo.ifi_index = if_nametoindex(dev_name);
+ if (req.ifinfo.ifi_index == 0) {
+ fprintf(stderr, "bpf: Resolving device name to index: %s\n", strerror(errno));
+ goto cleanup;
+ }
+
+ nla = (struct nlattr *)(((char *)&req)
+ + NLMSG_ALIGN(req.nh.nlmsg_len));
+ nla->nla_type = NLA_F_NESTED | 43/*IFLA_XDP*/;
+
+ nla_xdp = (struct nlattr *)((char *)nla + NLA_HDRLEN);
+
+ // we specify the FD passed over by the user
+ nla_xdp->nla_type = 1/*IFLA_XDP_FD*/;
+ nla_xdp->nla_len = NLA_HDRLEN + sizeof(int);
+ memcpy((char *)nla_xdp + NLA_HDRLEN, &progfd, sizeof(progfd));
+ nla->nla_len = NLA_HDRLEN + nla_xdp->nla_len;
+
+ req.nh.nlmsg_len += NLA_ALIGN(nla->nla_len);
+
+ if (send(sock, &req, req.nh.nlmsg_len, 0) < 0) {
+ fprintf(stderr, "bpf: send to netlink: %s\n", strerror(errno));
+ goto cleanup;
+ }
+
+ len = recv(sock, buf, sizeof(buf), 0);
+ if (len < 0) {
+ fprintf(stderr, "bpf: recv from netlink: %s\n", strerror(errno));
+ goto cleanup;
+ }
+
+ for (nh = (struct nlmsghdr *)buf; NLMSG_OK(nh, len);
+ nh = NLMSG_NEXT(nh, len)) {
+ if (nh->nlmsg_pid != getpid()) {
+ fprintf(stderr, "bpf: Wrong pid %d, expected %d\n",
+ nh->nlmsg_pid, getpid());
+ errno = EBADMSG;
+ goto cleanup;
+ }
+ if (nh->nlmsg_seq != seq) {
+ fprintf(stderr, "bpf: Wrong seq %d, expected %d\n",
+ nh->nlmsg_seq, seq);
+ errno = EBADMSG;
+ goto cleanup;
+ }
+ switch (nh->nlmsg_type) {
+ case NLMSG_ERROR:
+ err = (struct nlmsgerr *)NLMSG_DATA(nh);
+ if (!err->error)
+ continue;
+ fprintf(stderr, "bpf: nlmsg error %s\n", strerror(-err->error));
+ errno = -err->error;
+ goto cleanup;
+ case NLMSG_DONE:
+ break;
+ }
+ }
+
+ ret = 0;
+
+cleanup:
+ close(sock);
+ return ret;
+}

src/libbpf.h

@@ -61,6 +61,9 @@ int bpf_detach_tracepoint(const char *tp_category, const char *tp_name);
 
 void * bpf_open_perf_buffer(perf_reader_raw_cb raw_cb, void *cb_cookie, int pid, int cpu);
 
+/* attached a prog expressed by progfd to the device specified in dev_name */
+int bpf_attach_xdp(const char *dev_name, int progfd);
+
 #define LOG_BUF_SIZE 65536
 extern char bpf_log_buf[LOG_BUF_SIZE];