// SPDX-License-Identifier: GPL-2.0
#include <test_progs.h>
#include <network_helpers.h>
#include <net/if.h>
#include "test_xdp.skel.h"
#include "test_xdp_bpf2bpf.skel.h"

struct meta {
        int ifindex;
        int pkt_len;
};

struct test_ctx_s {
        bool passed;
        int pkt_size;
};

struct test_ctx_s test_ctx;

static void on_sample(void *ctx, int cpu, void *data, __u32 size)
{
        struct meta *meta = (struct meta *)data;
        struct ipv4_packet *trace_pkt_v4 = data + sizeof(*meta);
        unsigned char *raw_pkt = data + sizeof(*meta);
        struct test_ctx_s *tst_ctx = ctx;

        ASSERT_GE(size, sizeof(pkt_v4) + sizeof(*meta), "check_size");
        ASSERT_EQ(meta->ifindex, if_nametoindex("lo"), "check_meta_ifindex");
        ASSERT_EQ(meta->pkt_len, tst_ctx->pkt_size, "check_meta_pkt_len");
        ASSERT_EQ(memcmp(trace_pkt_v4, &pkt_v4, sizeof(pkt_v4)), 0,
                  "check_packet_content");

        if (meta->pkt_len > sizeof(pkt_v4)) {
                for (int i = 0; i < meta->pkt_len - sizeof(pkt_v4); i++)
                        ASSERT_EQ(raw_pkt[i + sizeof(pkt_v4)], (unsigned char)i,
                                  "check_packet_content");
        }

        tst_ctx->passed = true;
}

#define BUF_SZ  9000

static void run_xdp_bpf2bpf_pkt_size(int pkt_fd, struct perf_buffer *pb,
                                     struct test_xdp_bpf2bpf *ftrace_skel,
                                     int pkt_size)
{
        __u8 *buf, *buf_in;
        int err;
        LIBBPF_OPTS(bpf_test_run_opts, topts);

        if (!ASSERT_LE(pkt_size, BUF_SZ, "pkt_size") ||
            !ASSERT_GE(pkt_size, sizeof(pkt_v4), "pkt_size"))
                return;

        buf_in = malloc(BUF_SZ);
        if (!ASSERT_OK_PTR(buf_in, "buf_in malloc()"))
                return;

        buf = malloc(BUF_SZ);
        if (!ASSERT_OK_PTR(buf, "buf malloc()")) {
                free(buf_in);
                return;
        }

        test_ctx.passed = false;
        test_ctx.pkt_size = pkt_size;

        memcpy(buf_in, &pkt_v4, sizeof(pkt_v4));
        if (pkt_size > sizeof(pkt_v4)) {
                for (int i = 0; i < (pkt_size - sizeof(pkt_v4)); i++)
                        buf_in[i + sizeof(pkt_v4)] = i;
        }

        /* Run test program */
        topts.data_in = buf_in;
        topts.data_size_in = pkt_size;
        topts.data_out = buf;
        topts.data_size_out = BUF_SZ;

        err = bpf_prog_test_run_opts(pkt_fd, &topts);

        ASSERT_OK(err, "ipv4");
        ASSERT_EQ(topts.retval, XDP_PASS, "ipv4 retval");
        ASSERT_EQ(topts.data_size_out, pkt_size, "ipv4 size");

        /* Make sure bpf_xdp_output() was triggered and it sent the expected
         * data to the perf ring buffer.
         */
        err = perf_buffer__poll(pb, 100);

        ASSERT_GE(err, 0, "perf_buffer__poll");
        ASSERT_TRUE(test_ctx.passed, "test passed");
        /* Verify test results */
        ASSERT_EQ(ftrace_skel->bss->test_result_fentry, if_nametoindex("lo"),
                  "fentry result");
        ASSERT_EQ(ftrace_skel->bss->test_result_fexit, XDP_PASS, "fexit result");

        free(buf);
        free(buf_in);
}

void test_xdp_bpf2bpf(void)
{
        int err, pkt_fd, map_fd;
        int pkt_sizes[] = {sizeof(pkt_v4), 1024, 4100, 8200};
        struct iptnl_info value4 = {.family = AF_INET6};
        struct test_xdp *pkt_skel = NULL;
        struct test_xdp_bpf2bpf *ftrace_skel = NULL;
        struct vip key4 = {.protocol = 6, .family = AF_INET};
        struct bpf_program *prog;
        struct perf_buffer *pb = NULL;

        /* Load XDP program to introspect */
        pkt_skel = test_xdp__open_and_load();
        if (!ASSERT_OK_PTR(pkt_skel, "test_xdp__open_and_load"))
                return;

        pkt_fd = bpf_program__fd(pkt_skel->progs._xdp_tx_iptunnel);

        map_fd = bpf_map__fd(pkt_skel->maps.vip2tnl);
        bpf_map_update_elem(map_fd, &key4, &value4, 0);

        /* Load trace program */
        ftrace_skel = test_xdp_bpf2bpf__open();
        if (!ASSERT_OK_PTR(ftrace_skel, "test_xdp_bpf2bpf__open"))
                goto out;

        /* Demonstrate the bpf_program__set_attach_target() API rather than
         * the load with options, i.e. opts.attach_prog_fd.
         */
        prog = ftrace_skel->progs.trace_on_entry;
        bpf_program__set_expected_attach_type(prog, BPF_TRACE_FENTRY);
        bpf_program__set_attach_target(prog, pkt_fd, "_xdp_tx_iptunnel");

        prog = ftrace_skel->progs.trace_on_exit;
        bpf_program__set_expected_attach_type(prog, BPF_TRACE_FEXIT);
        bpf_program__set_attach_target(prog, pkt_fd, "_xdp_tx_iptunnel");

        err = test_xdp_bpf2bpf__load(ftrace_skel);
        if (!ASSERT_OK(err, "test_xdp_bpf2bpf__load"))
                goto out;

        err = test_xdp_bpf2bpf__attach(ftrace_skel);
        if (!ASSERT_OK(err, "test_xdp_bpf2bpf__attach"))
                goto out;

        /* Set up perf buffer */
        pb = perf_buffer__new(bpf_map__fd(ftrace_skel->maps.perf_buf_map), 8,
                              on_sample, NULL, &test_ctx, NULL);
        if (!ASSERT_OK_PTR(pb, "perf_buf__new"))
                goto out;

        for (int i = 0; i < ARRAY_SIZE(pkt_sizes); i++)
                run_xdp_bpf2bpf_pkt_size(pkt_fd, pb, ftrace_skel,
                                         pkt_sizes[i]);
out:
        perf_buffer__free(pb);
        test_xdp__destroy(pkt_skel);
        test_xdp_bpf2bpf__destroy(ftrace_skel);
}