This patch adds a set of kfuncs to bpf_testmod that can be used to manipulate a socket from kernel space.
Signed-off-by: Jordan Rife jrife@google.com --- .../selftests/bpf/bpf_testmod/bpf_testmod.c | 139 ++++++++++++++++++ .../bpf/bpf_testmod/bpf_testmod_kfunc.h | 27 ++++ 2 files changed, 166 insertions(+)
diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c index 39ad96a18123f..663df8148097e 100644 --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c @@ -10,18 +10,29 @@ #include <linux/percpu-defs.h> #include <linux/sysfs.h> #include <linux/tracepoint.h> +#include <linux/net.h> +#include <linux/socket.h> +#include <linux/nsproxy.h> +#include <linux/inet.h> +#include <linux/in.h> +#include <linux/in6.h> +#include <linux/un.h> +#include <net/sock.h> #include "bpf_testmod.h" #include "bpf_testmod_kfunc.h"
#define CREATE_TRACE_POINTS #include "bpf_testmod-events.h"
+#define CONNECT_TIMEOUT_SEC 1 + typedef int (*func_proto_typedef)(long); typedef int (*func_proto_typedef_nested1)(func_proto_typedef); typedef int (*func_proto_typedef_nested2)(func_proto_typedef_nested1);
DEFINE_PER_CPU(int, bpf_testmod_ksym_percpu) = 123; long bpf_testmod_test_struct_arg_result; +static struct socket *sock;
struct bpf_testmod_struct_arg_1 { int a; @@ -494,6 +505,124 @@ __bpf_kfunc static u32 bpf_kfunc_call_test_static_unused_arg(u32 arg, u32 unused return arg; }
+__bpf_kfunc int bpf_kfunc_init_sock(struct init_sock_args *args) +{ + int proto; + + if (sock) + pr_warn("%s called without releasing old sock", __func__); + + switch (args->af) { + case AF_INET: + case AF_INET6: + proto = args->type == SOCK_STREAM ? IPPROTO_TCP : IPPROTO_UDP; + break; + case AF_UNIX: + proto = PF_UNIX; + break; + default: + pr_err("invalid address family %d\n", args->af); + return -EINVAL; + } + + return sock_create_kern(&init_net, args->af, args->type, proto, &sock); +} + +__bpf_kfunc void bpf_kfunc_close_sock(void) +{ + if (sock) { + sock_release(sock); + sock = NULL; + } +} + +__bpf_kfunc int bpf_kfunc_call_kernel_connect(struct addr_args *args) +{ + /* Set timeout for call to kernel_connect() to prevent it from hanging, + * and consider the connection attempt failed if it returns + * -EINPROGRESS. + */ + sock->sk->sk_sndtimeo = CONNECT_TIMEOUT_SEC * HZ; + + return kernel_connect(sock, (struct sockaddr *)&args->addr, + args->addrlen, 0); +} + +__bpf_kfunc int bpf_kfunc_call_kernel_bind(struct addr_args *args) +{ + return kernel_bind(sock, (struct sockaddr *)&args->addr, args->addrlen); +} + +__bpf_kfunc int bpf_kfunc_call_kernel_listen(void) +{ + return kernel_listen(sock, 128); +} + +__bpf_kfunc int bpf_kfunc_call_kernel_sendmsg(struct sendmsg_args *args) +{ + struct msghdr msg = { + .msg_name = &args->addr.addr, + .msg_namelen = args->addr.addrlen, + }; + struct kvec iov; + int err; + + iov.iov_base = args->msg; + iov.iov_len = args->msglen; + + err = kernel_sendmsg(sock, &msg, &iov, 1, args->msglen); + args->addr.addrlen = msg.msg_namelen; + + return err; +} + +__bpf_kfunc int bpf_kfunc_call_sock_sendmsg(struct sendmsg_args *args) +{ + struct msghdr msg = { + .msg_name = &args->addr.addr, + .msg_namelen = args->addr.addrlen, + }; + struct kvec iov; + int err; + + iov.iov_base = args->msg; + iov.iov_len = args->msglen; + + iov_iter_kvec(&msg.msg_iter, ITER_SOURCE, &iov, 1, args->msglen); + err = sock_sendmsg(sock, &msg); + args->addr.addrlen = msg.msg_namelen; + + return err; +} + +__bpf_kfunc int bpf_kfunc_call_kernel_getsockname(struct addr_args *args) +{ + int err; + + err = kernel_getsockname(sock, (struct sockaddr *)&args->addr); + if (err < 0) + goto out; + + args->addrlen = err; + err = 0; +out: + return err; +} + +__bpf_kfunc int bpf_kfunc_call_kernel_getpeername(struct addr_args *args) +{ + int err; + + err = kernel_getpeername(sock, (struct sockaddr *)&args->addr); + if (err < 0) + goto out; + + args->addrlen = err; + err = 0; +out: + return err; +} + BTF_KFUNCS_START(bpf_testmod_check_kfunc_ids) BTF_ID_FLAGS(func, bpf_testmod_test_mod_kfunc) BTF_ID_FLAGS(func, bpf_kfunc_call_test1) @@ -520,6 +649,15 @@ BTF_ID_FLAGS(func, bpf_kfunc_call_test_ref, KF_TRUSTED_ARGS | KF_RCU) BTF_ID_FLAGS(func, bpf_kfunc_call_test_destructive, KF_DESTRUCTIVE) BTF_ID_FLAGS(func, bpf_kfunc_call_test_static_unused_arg) BTF_ID_FLAGS(func, bpf_kfunc_call_test_offset) +BTF_ID_FLAGS(func, bpf_kfunc_init_sock) +BTF_ID_FLAGS(func, bpf_kfunc_close_sock) +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_connect) +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_bind) +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_listen) +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_sendmsg) +BTF_ID_FLAGS(func, bpf_kfunc_call_sock_sendmsg) +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_getsockname) +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_getpeername) BTF_KFUNCS_END(bpf_testmod_check_kfunc_ids)
static int bpf_testmod_ops_init(struct btf *btf) @@ -650,6 +788,7 @@ static int bpf_testmod_init(void) return ret; if (bpf_fentry_test1(0) < 0) return -EINVAL; + sock = NULL; return sysfs_create_bin_file(kernel_kobj, &bin_attr_bpf_testmod_file); }
diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h index 7c664dd610597..cdf7769a7d8ca 100644 --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h @@ -64,6 +64,22 @@ struct prog_test_fail3 { char arr2[]; };
+struct init_sock_args { + int af; + int type; +}; + +struct addr_args { + char addr[sizeof(struct __kernel_sockaddr_storage)]; + int addrlen; +}; + +struct sendmsg_args { + struct addr_args addr; + char msg[10]; + int msglen; +}; + struct prog_test_ref_kfunc * bpf_kfunc_call_test_acquire(unsigned long *scalar_ptr) __ksym; void bpf_kfunc_call_test_release(struct prog_test_ref_kfunc *p) __ksym; @@ -106,4 +122,15 @@ void bpf_kfunc_call_test_fail3(struct prog_test_fail3 *p); void bpf_kfunc_call_test_mem_len_fail1(void *mem, int len);
void bpf_kfunc_common_test(void) __ksym; + +int bpf_kfunc_init_sock(struct init_sock_args *args) __ksym; +void bpf_kfunc_close_sock(void) __ksym; +int bpf_kfunc_call_kernel_connect(struct addr_args *args) __ksym; +int bpf_kfunc_call_kernel_bind(struct addr_args *args) __ksym; +int bpf_kfunc_call_kernel_listen(void) __ksym; +int bpf_kfunc_call_kernel_sendmsg(struct sendmsg_args *args) __ksym; +int bpf_kfunc_call_sock_sendmsg(struct sendmsg_args *args) __ksym; +int bpf_kfunc_call_kernel_getsockname(struct addr_args *args) __ksym; +int bpf_kfunc_call_kernel_getpeername(struct addr_args *args) __ksym; + #endif /* _BPF_TESTMOD_KFUNC_H */