bpf/prog_tests/xdp_adjust_frags.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 #include <test_progs.h>
0003 #include <network_helpers.h>
0004
0005 static void test_xdp_update_frags(void)
0006 {
0007     const char *file = "./test_xdp_update_frags.o";
0008     int err, prog_fd, max_skb_frags, buf_size, num;
0009     struct bpf_program *prog;
0010     struct bpf_object *obj;
0011     __u32 *offset;
0012     __u8 *buf;
0013     FILE *f;
0014     LIBBPF_OPTS(bpf_test_run_opts, topts);
0015
0016     obj = bpf_object__open(file);
0017     if (libbpf_get_error(obj))
0018         return;
0019
0020     prog = bpf_object__next_program(obj, NULL);
0021     if (bpf_object__load(obj))
0022         return;
0023
0024     prog_fd = bpf_program__fd(prog);
0025
0026     buf = malloc(128);
0027     if (!ASSERT_OK_PTR(buf, "alloc buf 128b"))
0028         goto out;
0029
0030     memset(buf, 0, 128);
0031     offset = (__u32 *)buf;
0032     *offset = 16;
0033     buf[*offset] = 0xaa;        /* marker at offset 16 (head) */
0034     buf[*offset + 15] = 0xaa;   /* marker at offset 31 (head) */
0035
0036     topts.data_in = buf;
0037     topts.data_out = buf;
0038     topts.data_size_in = 128;
0039     topts.data_size_out = 128;
0040
0041     err = bpf_prog_test_run_opts(prog_fd, &topts);
0042
0043     /* test_xdp_update_frags: buf[16,31]: 0xaa -> 0xbb */
0044     ASSERT_OK(err, "xdp_update_frag");
0045     ASSERT_EQ(topts.retval, XDP_PASS, "xdp_update_frag retval");
0046     ASSERT_EQ(buf[16], 0xbb, "xdp_update_frag buf[16]");
0047     ASSERT_EQ(buf[31], 0xbb, "xdp_update_frag buf[31]");
0048
0049     free(buf);
0050
0051     buf = malloc(9000);
0052     if (!ASSERT_OK_PTR(buf, "alloc buf 9Kb"))
0053         goto out;
0054
0055     memset(buf, 0, 9000);
0056     offset = (__u32 *)buf;
0057     *offset = 5000;
0058     buf[*offset] = 0xaa;        /* marker at offset 5000 (frag0) */
0059     buf[*offset + 15] = 0xaa;   /* marker at offset 5015 (frag0) */
0060
0061     topts.data_in = buf;
0062     topts.data_out = buf;
0063     topts.data_size_in = 9000;
0064     topts.data_size_out = 9000;
0065
0066     err = bpf_prog_test_run_opts(prog_fd, &topts);
0067
0068     /* test_xdp_update_frags: buf[5000,5015]: 0xaa -> 0xbb */
0069     ASSERT_OK(err, "xdp_update_frag");
0070     ASSERT_EQ(topts.retval, XDP_PASS, "xdp_update_frag retval");
0071     ASSERT_EQ(buf[5000], 0xbb, "xdp_update_frag buf[5000]");
0072     ASSERT_EQ(buf[5015], 0xbb, "xdp_update_frag buf[5015]");
0073
0074     memset(buf, 0, 9000);
0075     offset = (__u32 *)buf;
0076     *offset = 3510;
0077     buf[*offset] = 0xaa;        /* marker at offset 3510 (head) */
0078     buf[*offset + 15] = 0xaa;   /* marker at offset 3525 (frag0) */
0079
0080     err = bpf_prog_test_run_opts(prog_fd, &topts);
0081
0082     /* test_xdp_update_frags: buf[3510,3525]: 0xaa -> 0xbb */
0083     ASSERT_OK(err, "xdp_update_frag");
0084     ASSERT_EQ(topts.retval, XDP_PASS, "xdp_update_frag retval");
0085     ASSERT_EQ(buf[3510], 0xbb, "xdp_update_frag buf[3510]");
0086     ASSERT_EQ(buf[3525], 0xbb, "xdp_update_frag buf[3525]");
0087
0088     memset(buf, 0, 9000);
0089     offset = (__u32 *)buf;
0090     *offset = 7606;
0091     buf[*offset] = 0xaa;        /* marker at offset 7606 (frag0) */
0092     buf[*offset + 15] = 0xaa;   /* marker at offset 7621 (frag1) */
0093
0094     err = bpf_prog_test_run_opts(prog_fd, &topts);
0095
0096     /* test_xdp_update_frags: buf[7606,7621]: 0xaa -> 0xbb */
0097     ASSERT_OK(err, "xdp_update_frag");
0098     ASSERT_EQ(topts.retval, XDP_PASS, "xdp_update_frag retval");
0099     ASSERT_EQ(buf[7606], 0xbb, "xdp_update_frag buf[7606]");
0100     ASSERT_EQ(buf[7621], 0xbb, "xdp_update_frag buf[7621]");
0101
0102     free(buf);
0103
0104     /* test_xdp_update_frags: unsupported buffer size */
0105     f = fopen("/proc/sys/net/core/max_skb_frags", "r");
0106     if (!ASSERT_OK_PTR(f, "max_skb_frag file pointer"))
0107         goto out;
0108
0109     num = fscanf(f, "%d", &max_skb_frags);
0110     fclose(f);
0111
0112     if (!ASSERT_EQ(num, 1, "max_skb_frags read failed"))
0113         goto out;
0114
0115     /* xdp_buff linear area size is always set to 4096 in the
0116      * bpf_prog_test_run_xdp routine.
0117      */
0118     buf_size = 4096 + (max_skb_frags + 1) * sysconf(_SC_PAGE_SIZE);
0119     buf = malloc(buf_size);
0120     if (!ASSERT_OK_PTR(buf, "alloc buf"))
0121         goto out;
0122
0123     memset(buf, 0, buf_size);
0124     offset = (__u32 *)buf;
0125     *offset = 16;
0126     buf[*offset] = 0xaa;
0127     buf[*offset + 15] = 0xaa;
0128
0129     topts.data_in = buf;
0130     topts.data_out = buf;
0131     topts.data_size_in = buf_size;
0132     topts.data_size_out = buf_size;
0133
0134     err = bpf_prog_test_run_opts(prog_fd, &topts);
0135     ASSERT_EQ(err, -ENOMEM,
0136           "unsupported buf size, possible non-default /proc/sys/net/core/max_skb_flags?");
0137     free(buf);
0138 out:
0139     bpf_object__close(obj);
0140 }
0141
0142 void test_xdp_adjust_frags(void)
0143 {
0144     if (test__start_subtest("xdp_adjust_frags"))
0145         test_xdp_update_frags();
0146 }