new file mode 100644
@@ -0,0 +1,37 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/stddef.h>
+#include <linux/bpf.h>
+#include <linux/in.h>
+#include <sys/socket.h>
+
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_endian.h>
+
+#define SERV4_IP 0xc0a801feU /* 192.168.1.254 */
+#define SERV4_PORT 4040
+
+SEC("cgroup/recvmsg4")
+int recvmsg4_prog(struct bpf_sock_addr *ctx)
+{
+ struct bpf_sock *sk;
+ __u32 user_ip4;
+ __u16 user_port;
+
+ sk = ctx->sk;
+ if (!sk)
+ return 1;
+
+ if (sk->family != AF_INET)
+ return 1;
+
+ if (ctx->type != SOCK_STREAM && ctx->type != SOCK_DGRAM)
+ return 1;
+
+ ctx->user_ip4 = bpf_htonl(SERV4_IP);
+ ctx->user_port = bpf_htons(SERV4_PORT);
+
+ return 1;
+}
+
+char _license[] SEC("license") = "GPL";
new file mode 100644
@@ -0,0 +1,43 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/stddef.h>
+#include <linux/bpf.h>
+#include <linux/in6.h>
+#include <sys/socket.h>
+
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_endian.h>
+
+#define SERV6_IP_0 0xfaceb00c /* face:b00c:1234:5678::abcd */
+#define SERV6_IP_1 0x12345678
+#define SERV6_IP_2 0x00000000
+#define SERV6_IP_3 0x0000abcd
+#define SERV6_PORT 6060
+
+SEC("cgroup/recvmsg6")
+int recvmsg6_prog(struct bpf_sock_addr *ctx)
+{
+ struct bpf_sock *sk;
+ __u32 user_ip4;
+ __u16 user_port;
+
+ sk = ctx->sk;
+ if (!sk)
+ return 1;
+
+ if (sk->family != AF_INET6)
+ return 1;
+
+ if (ctx->type != SOCK_STREAM && ctx->type != SOCK_DGRAM)
+ return 1;
+
+ ctx->user_ip6[0] = bpf_htonl(SERV6_IP_0);
+ ctx->user_ip6[1] = bpf_htonl(SERV6_IP_1);
+ ctx->user_ip6[2] = bpf_htonl(SERV6_IP_2);
+ ctx->user_ip6[3] = bpf_htonl(SERV6_IP_3);
+ ctx->user_port = bpf_htons(SERV6_PORT);
+
+ return 1;
+}
+
+char _license[] SEC("license") = "GPL";
@@ -31,6 +31,8 @@
#define CONNECT6_PROG_PATH "./connect6_prog.o"
#define SENDMSG4_PROG_PATH "./sendmsg4_prog.o"
#define SENDMSG6_PROG_PATH "./sendmsg6_prog.o"
+#define RECVMSG4_PROG_PATH "./recvmsg4_prog.o"
+#define RECVMSG6_PROG_PATH "./recvmsg6_prog.o"
#define BIND4_PROG_PATH "./bind4_prog.o"
#define BIND6_PROG_PATH "./bind6_prog.o"
@@ -94,10 +96,10 @@ static int sendmsg_deny_prog_load(const struct sock_addr_test *test);
static int recvmsg_allow_prog_load(const struct sock_addr_test *test);
static int recvmsg_deny_prog_load(const struct sock_addr_test *test);
static int sendmsg4_rw_asm_prog_load(const struct sock_addr_test *test);
-static int recvmsg4_rw_asm_prog_load(const struct sock_addr_test *test);
+static int recvmsg4_rw_c_prog_load(const struct sock_addr_test *test);
static int sendmsg4_rw_c_prog_load(const struct sock_addr_test *test);
static int sendmsg6_rw_asm_prog_load(const struct sock_addr_test *test);
-static int recvmsg6_rw_asm_prog_load(const struct sock_addr_test *test);
+static int recvmsg6_rw_c_prog_load(const struct sock_addr_test *test);
static int sendmsg6_rw_c_prog_load(const struct sock_addr_test *test);
static int sendmsg6_rw_v4mapped_prog_load(const struct sock_addr_test *test);
static int sendmsg6_rw_wildcard_prog_load(const struct sock_addr_test *test);
@@ -573,8 +575,8 @@ static struct sock_addr_test tests[] = {
LOAD_REJECT,
},
{
- "recvmsg4: rewrite IP & port (asm)",
- recvmsg4_rw_asm_prog_load,
+ "recvmsg4: rewrite IP & port (C)",
+ recvmsg4_rw_c_prog_load,
BPF_CGROUP_UDP4_RECVMSG,
BPF_CGROUP_UDP4_RECVMSG,
AF_INET,
@@ -587,8 +589,8 @@ static struct sock_addr_test tests[] = {
SUCCESS,
},
{
- "recvmsg6: rewrite IP & port (asm)",
- recvmsg6_rw_asm_prog_load,
+ "recvmsg6: rewrite IP & port (C)",
+ recvmsg6_rw_c_prog_load,
BPF_CGROUP_UDP6_RECVMSG,
BPF_CGROUP_UDP6_RECVMSG,
AF_INET6,
@@ -786,45 +788,9 @@ static int sendmsg4_rw_asm_prog_load(const struct sock_addr_test *test)
return load_insns(test, insns, sizeof(insns) / sizeof(struct bpf_insn));
}
-static int recvmsg4_rw_asm_prog_load(const struct sock_addr_test *test)
+static int recvmsg4_rw_c_prog_load(const struct sock_addr_test *test)
{
- struct sockaddr_in src4_rw_addr;
-
- if (mk_sockaddr(AF_INET, SERV4_IP, SERV4_PORT,
- (struct sockaddr *)&src4_rw_addr,
- sizeof(src4_rw_addr)) == -1)
- return -1;
-
- struct bpf_insn insns[] = {
- BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
-
- /* if (sk.family == AF_INET && */
- BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_6,
- offsetof(struct bpf_sock_addr, family)),
- BPF_JMP_IMM(BPF_JNE, BPF_REG_7, AF_INET, 6),
-
- /* sk.type == SOCK_DGRAM) { */
- BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_6,
- offsetof(struct bpf_sock_addr, type)),
- BPF_JMP_IMM(BPF_JNE, BPF_REG_7, SOCK_DGRAM, 4),
-
- /* user_ip4 = src4_rw_addr.sin_addr */
- BPF_MOV32_IMM(BPF_REG_7, src4_rw_addr.sin_addr.s_addr),
- BPF_STX_MEM(BPF_W, BPF_REG_6, BPF_REG_7,
- offsetof(struct bpf_sock_addr, user_ip4)),
-
- /* user_port = src4_rw_addr.sin_port */
- BPF_MOV32_IMM(BPF_REG_7, src4_rw_addr.sin_port),
- BPF_STX_MEM(BPF_W, BPF_REG_6, BPF_REG_7,
- offsetof(struct bpf_sock_addr, user_port)),
- /* } */
-
- /* return 1 */
- BPF_MOV64_IMM(BPF_REG_0, 1),
- BPF_EXIT_INSN(),
- };
-
- return load_insns(test, insns, sizeof(insns) / sizeof(struct bpf_insn));
+ return load_path(test, RECVMSG4_PROG_PATH);
}
static int sendmsg4_rw_c_prog_load(const struct sock_addr_test *test)
@@ -890,37 +856,9 @@ static int sendmsg6_rw_asm_prog_load(const struct sock_addr_test *test)
return sendmsg6_rw_dst_asm_prog_load(test, SERV6_REWRITE_IP);
}
-static int recvmsg6_rw_asm_prog_load(const struct sock_addr_test *test)
+static int recvmsg6_rw_c_prog_load(const struct sock_addr_test *test)
{
- struct sockaddr_in6 src6_rw_addr;
-
- if (mk_sockaddr(AF_INET6, SERV6_IP, SERV6_PORT,
- (struct sockaddr *)&src6_rw_addr,
- sizeof(src6_rw_addr)) == -1)
- return -1;
-
- struct bpf_insn insns[] = {
- BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
-
- /* if (sk.family == AF_INET6) { */
- BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_6,
- offsetof(struct bpf_sock_addr, family)),
- BPF_JMP_IMM(BPF_JNE, BPF_REG_7, AF_INET6, 10),
-
- STORE_IPV6(user_ip6, src6_rw_addr.sin6_addr.s6_addr32),
-
- /* user_port = dst6_rw_addr.sin6_port */
- BPF_MOV32_IMM(BPF_REG_7, src6_rw_addr.sin6_port),
- BPF_STX_MEM(BPF_W, BPF_REG_6, BPF_REG_7,
- offsetof(struct bpf_sock_addr, user_port)),
- /* } */
-
- /* return 1 */
- BPF_MOV64_IMM(BPF_REG_0, 1),
- BPF_EXIT_INSN(),
- };
-
- return load_insns(test, insns, sizeof(insns) / sizeof(struct bpf_insn));
+ return load_path(test, RECVMSG6_PROG_PATH);
}
static int sendmsg6_rw_v4mapped_prog_load(const struct sock_addr_test *test)
I'll extend them in the next patch. It's easier to work with C than with asm. Signed-off-by: Stanislav Fomichev <sdf@google.com> --- .../selftests/bpf/progs/recvmsg4_prog.c | 37 ++++++++ .../selftests/bpf/progs/recvmsg6_prog.c | 43 ++++++++++ tools/testing/selftests/bpf/test_sock_addr.c | 86 +++---------------- 3 files changed, 92 insertions(+), 74 deletions(-) create mode 100644 tools/testing/selftests/bpf/progs/recvmsg4_prog.c create mode 100644 tools/testing/selftests/bpf/progs/recvmsg6_prog.c