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-rw-r--r--include/linux/bpf-cgroup.h18
-rw-r--r--include/linux/bpf_types.h1
-rw-r--r--include/linux/filter.h9
-rw-r--r--include/net/tcp.h36
-rw-r--r--include/uapi/linux/bpf.h30
-rw-r--r--kernel/bpf/cgroup.c37
-rw-r--r--kernel/bpf/syscall.c5
-rw-r--r--net/core/filter.c168
-rw-r--r--samples/bpf/bpf_load.c13
9 files changed, 314 insertions, 3 deletions
diff --git a/include/linux/bpf-cgroup.h b/include/linux/bpf-cgroup.h
index c970a25d2a49..360c082e885c 100644
--- a/include/linux/bpf-cgroup.h
+++ b/include/linux/bpf-cgroup.h
@@ -7,6 +7,7 @@
struct sock;
struct cgroup;
struct sk_buff;
+struct bpf_sock_ops_kern;
#ifdef CONFIG_CGROUP_BPF
@@ -42,6 +43,10 @@ int __cgroup_bpf_run_filter_skb(struct sock *sk,
int __cgroup_bpf_run_filter_sk(struct sock *sk,
enum bpf_attach_type type);
+int __cgroup_bpf_run_filter_sock_ops(struct sock *sk,
+ struct bpf_sock_ops_kern *sock_ops,
+ enum bpf_attach_type type);
+
/* Wrappers for __cgroup_bpf_run_filter_skb() guarded by cgroup_bpf_enabled. */
#define BPF_CGROUP_RUN_PROG_INET_INGRESS(sk, skb) \
({ \
@@ -75,6 +80,18 @@ int __cgroup_bpf_run_filter_sk(struct sock *sk,
__ret; \
})
+#define BPF_CGROUP_RUN_PROG_SOCK_OPS(sock_ops) \
+({ \
+ int __ret = 0; \
+ if (cgroup_bpf_enabled && (sock_ops)->sk) { \
+ typeof(sk) __sk = sk_to_full_sk((sock_ops)->sk); \
+ if (sk_fullsock(__sk)) \
+ __ret = __cgroup_bpf_run_filter_sock_ops(__sk, \
+ sock_ops, \
+ BPF_CGROUP_SOCK_OPS); \
+ } \
+ __ret; \
+})
#else
struct cgroup_bpf {};
@@ -85,6 +102,7 @@ static inline void cgroup_bpf_inherit(struct cgroup *cgrp,
#define BPF_CGROUP_RUN_PROG_INET_INGRESS(sk,skb) ({ 0; })
#define BPF_CGROUP_RUN_PROG_INET_EGRESS(sk,skb) ({ 0; })
#define BPF_CGROUP_RUN_PROG_INET_SOCK(sk) ({ 0; })
+#define BPF_CGROUP_RUN_PROG_SOCK_OPS(sock_ops) ({ 0; })
#endif /* CONFIG_CGROUP_BPF */
diff --git a/include/linux/bpf_types.h b/include/linux/bpf_types.h
index 03bf223f18be..3d137c33d664 100644
--- a/include/linux/bpf_types.h
+++ b/include/linux/bpf_types.h
@@ -10,6 +10,7 @@ BPF_PROG_TYPE(BPF_PROG_TYPE_CGROUP_SOCK, cg_sock_prog_ops)
BPF_PROG_TYPE(BPF_PROG_TYPE_LWT_IN, lwt_inout_prog_ops)
BPF_PROG_TYPE(BPF_PROG_TYPE_LWT_OUT, lwt_inout_prog_ops)
BPF_PROG_TYPE(BPF_PROG_TYPE_LWT_XMIT, lwt_xmit_prog_ops)
+BPF_PROG_TYPE(BPF_PROG_TYPE_SOCK_OPS, sock_ops_prog_ops)
#endif
#ifdef CONFIG_BPF_EVENTS
BPF_PROG_TYPE(BPF_PROG_TYPE_KPROBE, kprobe_prog_ops)
diff --git a/include/linux/filter.h b/include/linux/filter.h
index 1fa26dc562ce..738f8b14f025 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -898,4 +898,13 @@ static inline int bpf_tell_extensions(void)
return SKF_AD_MAX;
}
+struct bpf_sock_ops_kern {
+ struct sock *sk;
+ u32 op;
+ union {
+ u32 reply;
+ u32 replylong[4];
+ };
+};
+
#endif /* __LINUX_FILTER_H__ */
diff --git a/include/net/tcp.h b/include/net/tcp.h
index d0751b79d99c..e58500825006 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -46,6 +46,10 @@
#include <linux/seq_file.h>
#include <linux/memcontrol.h>
+#include <linux/bpf.h>
+#include <linux/filter.h>
+#include <linux/bpf-cgroup.h>
+
extern struct inet_hashinfo tcp_hashinfo;
extern struct percpu_counter tcp_orphan_count;
@@ -2021,4 +2025,36 @@ int tcp_set_ulp(struct sock *sk, const char *name);
void tcp_get_available_ulp(char *buf, size_t len);
void tcp_cleanup_ulp(struct sock *sk);
+/* Call BPF_SOCK_OPS program that returns an int. If the return value
+ * is < 0, then the BPF op failed (for example if the loaded BPF
+ * program does not support the chosen operation or there is no BPF
+ * program loaded).
+ */
+#ifdef CONFIG_BPF
+static inline int tcp_call_bpf(struct sock *sk, int op)
+{
+ struct bpf_sock_ops_kern sock_ops;
+ int ret;
+
+ if (sk_fullsock(sk))
+ sock_owned_by_me(sk);
+
+ memset(&sock_ops, 0, sizeof(sock_ops));
+ sock_ops.sk = sk;
+ sock_ops.op = op;
+
+ ret = BPF_CGROUP_RUN_PROG_SOCK_OPS(&sock_ops);
+ if (ret == 0)
+ ret = sock_ops.reply;
+ else
+ ret = -1;
+ return ret;
+}
+#else
+static inline int tcp_call_bpf(struct sock *sk, int op)
+{
+ return -EPERM;
+}
+#endif
+
#endif /* _TCP_H */
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index f94b48b168dc..01cd485ccd4f 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -120,12 +120,14 @@ enum bpf_prog_type {
BPF_PROG_TYPE_LWT_IN,
BPF_PROG_TYPE_LWT_OUT,
BPF_PROG_TYPE_LWT_XMIT,
+ BPF_PROG_TYPE_SOCK_OPS,
};
enum bpf_attach_type {
BPF_CGROUP_INET_INGRESS,
BPF_CGROUP_INET_EGRESS,
BPF_CGROUP_INET_SOCK_CREATE,
+ BPF_CGROUP_SOCK_OPS,
__MAX_BPF_ATTACH_TYPE
};
@@ -720,4 +722,32 @@ struct bpf_map_info {
__u32 map_flags;
} __attribute__((aligned(8)));
+/* User bpf_sock_ops struct to access socket values and specify request ops
+ * and their replies.
+ * Some of this fields are in network (bigendian) byte order and may need
+ * to be converted before use (bpf_ntohl() defined in samples/bpf/bpf_endian.h).
+ * New fields can only be added at the end of this structure
+ */
+struct bpf_sock_ops {
+ __u32 op;
+ union {
+ __u32 reply;
+ __u32 replylong[4];
+ };
+ __u32 family;
+ __u32 remote_ip4; /* Stored in network byte order */
+ __u32 local_ip4; /* Stored in network byte order */
+ __u32 remote_ip6[4]; /* Stored in network byte order */
+ __u32 local_ip6[4]; /* Stored in network byte order */
+ __u32 remote_port; /* Stored in network byte order */
+ __u32 local_port; /* stored in host byte order */
+};
+
+/* List of known BPF sock_ops operators.
+ * New entries can only be added at the end
+ */
+enum {
+ BPF_SOCK_OPS_VOID,
+};
+
#endif /* _UAPI__LINUX_BPF_H__ */
diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c
index ea6033cba947..546113430049 100644
--- a/kernel/bpf/cgroup.c
+++ b/kernel/bpf/cgroup.c
@@ -236,3 +236,40 @@ int __cgroup_bpf_run_filter_sk(struct sock *sk,
return ret;
}
EXPORT_SYMBOL(__cgroup_bpf_run_filter_sk);
+
+/**
+ * __cgroup_bpf_run_filter_sock_ops() - Run a program on a sock
+ * @sk: socket to get cgroup from
+ * @sock_ops: bpf_sock_ops_kern struct to pass to program. Contains
+ * sk with connection information (IP addresses, etc.) May not contain
+ * cgroup info if it is a req sock.
+ * @type: The type of program to be exectuted
+ *
+ * socket passed is expected to be of type INET or INET6.
+ *
+ * The program type passed in via @type must be suitable for sock_ops
+ * filtering. No further check is performed to assert that.
+ *
+ * This function will return %-EPERM if any if an attached program was found
+ * and if it returned != 1 during execution. In all other cases, 0 is returned.
+ */
+int __cgroup_bpf_run_filter_sock_ops(struct sock *sk,
+ struct bpf_sock_ops_kern *sock_ops,
+ enum bpf_attach_type type)
+{
+ struct cgroup *cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
+ struct bpf_prog *prog;
+ int ret = 0;
+
+
+ rcu_read_lock();
+
+ prog = rcu_dereference(cgrp->bpf.effective[type]);
+ if (prog)
+ ret = BPF_PROG_RUN(prog, sock_ops) == 1 ? 0 : -EPERM;
+
+ rcu_read_unlock();
+
+ return ret;
+}
+EXPORT_SYMBOL(__cgroup_bpf_run_filter_sock_ops);
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 4409ccca8831..d4d47de75bba 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -1079,6 +1079,9 @@ static int bpf_prog_attach(const union bpf_attr *attr)
case BPF_CGROUP_INET_SOCK_CREATE:
ptype = BPF_PROG_TYPE_CGROUP_SOCK;
break;
+ case BPF_CGROUP_SOCK_OPS:
+ ptype = BPF_PROG_TYPE_SOCK_OPS;
+ break;
default:
return -EINVAL;
}
@@ -1119,6 +1122,7 @@ static int bpf_prog_detach(const union bpf_attr *attr)
case BPF_CGROUP_INET_INGRESS:
case BPF_CGROUP_INET_EGRESS:
case BPF_CGROUP_INET_SOCK_CREATE:
+ case BPF_CGROUP_SOCK_OPS:
cgrp = cgroup_get_from_fd(attr->target_fd);
if (IS_ERR(cgrp))
return PTR_ERR(cgrp);
@@ -1133,6 +1137,7 @@ static int bpf_prog_detach(const union bpf_attr *attr)
return ret;
}
+
#endif /* CONFIG_CGROUP_BPF */
#define BPF_PROG_TEST_RUN_LAST_FIELD test.duration
diff --git a/net/core/filter.c b/net/core/filter.c
index b39c869d22e3..1f6a26c4f8b9 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -3110,6 +3110,36 @@ void bpf_warn_invalid_xdp_action(u32 act)
}
EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action);
+static bool __is_valid_sock_ops_access(int off, int size)
+{
+ if (off < 0 || off >= sizeof(struct bpf_sock_ops))
+ return false;
+ /* The verifier guarantees that size > 0. */
+ if (off % size != 0)
+ return false;
+ if (size != sizeof(__u32))
+ return false;
+
+ return true;
+}
+
+static bool sock_ops_is_valid_access(int off, int size,
+ enum bpf_access_type type,
+ struct bpf_insn_access_aux *info)
+{
+ if (type == BPF_WRITE) {
+ switch (off) {
+ case offsetof(struct bpf_sock_ops, op) ...
+ offsetof(struct bpf_sock_ops, replylong[3]):
+ break;
+ default:
+ return false;
+ }
+ }
+
+ return __is_valid_sock_ops_access(off, size);
+}
+
static u32 bpf_convert_ctx_access(enum bpf_access_type type,
const struct bpf_insn *si,
struct bpf_insn *insn_buf,
@@ -3379,6 +3409,138 @@ static u32 xdp_convert_ctx_access(enum bpf_access_type type,
return insn - insn_buf;
}
+static u32 sock_ops_convert_ctx_access(enum bpf_access_type type,
+ const struct bpf_insn *si,
+ struct bpf_insn *insn_buf,
+ struct bpf_prog *prog)
+{
+ struct bpf_insn *insn = insn_buf;
+ int off;
+
+ switch (si->off) {
+ case offsetof(struct bpf_sock_ops, op) ...
+ offsetof(struct bpf_sock_ops, replylong[3]):
+ BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, op) !=
+ FIELD_SIZEOF(struct bpf_sock_ops_kern, op));
+ BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, reply) !=
+ FIELD_SIZEOF(struct bpf_sock_ops_kern, reply));
+ BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, replylong) !=
+ FIELD_SIZEOF(struct bpf_sock_ops_kern, replylong));
+ off = si->off;
+ off -= offsetof(struct bpf_sock_ops, op);
+ off += offsetof(struct bpf_sock_ops_kern, op);
+ if (type == BPF_WRITE)
+ *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
+ off);
+ else
+ *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
+ off);
+ break;
+
+ case offsetof(struct bpf_sock_ops, family):
+ BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_family) != 2);
+
+ *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
+ struct bpf_sock_ops_kern, sk),
+ si->dst_reg, si->src_reg,
+ offsetof(struct bpf_sock_ops_kern, sk));
+ *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
+ offsetof(struct sock_common, skc_family));
+ break;
+
+ case offsetof(struct bpf_sock_ops, remote_ip4):
+ BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_daddr) != 4);
+
+ *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
+ struct bpf_sock_ops_kern, sk),
+ si->dst_reg, si->src_reg,
+ offsetof(struct bpf_sock_ops_kern, sk));
+ *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
+ offsetof(struct sock_common, skc_daddr));
+ break;
+
+ case offsetof(struct bpf_sock_ops, local_ip4):
+ BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_rcv_saddr) != 4);
+
+ *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
+ struct bpf_sock_ops_kern, sk),
+ si->dst_reg, si->src_reg,
+ offsetof(struct bpf_sock_ops_kern, sk));
+ *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
+ offsetof(struct sock_common,
+ skc_rcv_saddr));
+ break;
+
+ case offsetof(struct bpf_sock_ops, remote_ip6[0]) ...
+ offsetof(struct bpf_sock_ops, remote_ip6[3]):
+#if IS_ENABLED(CONFIG_IPV6)
+ BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
+ skc_v6_daddr.s6_addr32[0]) != 4);
+
+ off = si->off;
+ off -= offsetof(struct bpf_sock_ops, remote_ip6[0]);
+ *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
+ struct bpf_sock_ops_kern, sk),
+ si->dst_reg, si->src_reg,
+ offsetof(struct bpf_sock_ops_kern, sk));
+ *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
+ offsetof(struct sock_common,
+ skc_v6_daddr.s6_addr32[0]) +
+ off);
+#else
+ *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
+#endif
+ break;
+
+ case offsetof(struct bpf_sock_ops, local_ip6[0]) ...
+ offsetof(struct bpf_sock_ops, local_ip6[3]):
+#if IS_ENABLED(CONFIG_IPV6)
+ BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
+ skc_v6_rcv_saddr.s6_addr32[0]) != 4);
+
+ off = si->off;
+ off -= offsetof(struct bpf_sock_ops, local_ip6[0]);
+ *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
+ struct bpf_sock_ops_kern, sk),
+ si->dst_reg, si->src_reg,
+ offsetof(struct bpf_sock_ops_kern, sk));
+ *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
+ offsetof(struct sock_common,
+ skc_v6_rcv_saddr.s6_addr32[0]) +
+ off);
+#else
+ *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
+#endif
+ break;
+
+ case offsetof(struct bpf_sock_ops, remote_port):
+ BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_dport) != 2);
+
+ *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
+ struct bpf_sock_ops_kern, sk),
+ si->dst_reg, si->src_reg,
+ offsetof(struct bpf_sock_ops_kern, sk));
+ *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
+ offsetof(struct sock_common, skc_dport));
+#ifndef __BIG_ENDIAN_BITFIELD
+ *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
+#endif
+ break;
+
+ case offsetof(struct bpf_sock_ops, local_port):
+ BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_num) != 2);
+
+ *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
+ struct bpf_sock_ops_kern, sk),
+ si->dst_reg, si->src_reg,
+ offsetof(struct bpf_sock_ops_kern, sk));
+ *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
+ offsetof(struct sock_common, skc_num));
+ break;
+ }
+ return insn - insn_buf;
+}
+
const struct bpf_verifier_ops sk_filter_prog_ops = {
.get_func_proto = sk_filter_func_proto,
.is_valid_access = sk_filter_is_valid_access,
@@ -3428,6 +3590,12 @@ const struct bpf_verifier_ops cg_sock_prog_ops = {
.convert_ctx_access = sock_filter_convert_ctx_access,
};
+const struct bpf_verifier_ops sock_ops_prog_ops = {
+ .get_func_proto = bpf_base_func_proto,
+ .is_valid_access = sock_ops_is_valid_access,
+ .convert_ctx_access = sock_ops_convert_ctx_access,
+};
+
int sk_detach_filter(struct sock *sk)
{
int ret = -ENOENT;
diff --git a/samples/bpf/bpf_load.c b/samples/bpf/bpf_load.c
index a91c57dd8571..a4be7cfa6519 100644
--- a/samples/bpf/bpf_load.c
+++ b/samples/bpf/bpf_load.c
@@ -64,6 +64,7 @@ static int load_and_attach(const char *event, struct bpf_insn *prog, int size)
bool is_perf_event = strncmp(event, "perf_event", 10) == 0;
bool is_cgroup_skb = strncmp(event, "cgroup/skb", 10) == 0;
bool is_cgroup_sk = strncmp(event, "cgroup/sock", 11) == 0;
+ bool is_sockops = strncmp(event, "sockops", 7) == 0;
size_t insns_cnt = size / sizeof(struct bpf_insn);
enum bpf_prog_type prog_type;
char buf[256];
@@ -89,6 +90,8 @@ static int load_and_attach(const char *event, struct bpf_insn *prog, int size)
prog_type = BPF_PROG_TYPE_CGROUP_SKB;
} else if (is_cgroup_sk) {
prog_type = BPF_PROG_TYPE_CGROUP_SOCK;
+ } else if (is_sockops) {
+ prog_type = BPF_PROG_TYPE_SOCK_OPS;
} else {
printf("Unknown event '%s'\n", event);
return -1;
@@ -106,8 +109,11 @@ static int load_and_attach(const char *event, struct bpf_insn *prog, int size)
if (is_xdp || is_perf_event || is_cgroup_skb || is_cgroup_sk)
return 0;
- if (is_socket) {
- event += 6;
+ if (is_socket || is_sockops) {
+ if (is_socket)
+ event += 6;
+ else
+ event += 7;
if (*event != '/')
return 0;
event++;
@@ -560,7 +566,8 @@ static int do_load_bpf_file(const char *path, fixup_map_cb fixup_map)
memcmp(shname, "xdp", 3) == 0 ||
memcmp(shname, "perf_event", 10) == 0 ||
memcmp(shname, "socket", 6) == 0 ||
- memcmp(shname, "cgroup/", 7) == 0)
+ memcmp(shname, "cgroup/", 7) == 0 ||
+ memcmp(shname, "sockops", 7) == 0)
load_and_attach(shname, data->d_buf, data->d_size);
}
generated by cgit (git 2.34.1) at 2024-07-03 05:14:01 +0000