diff options
Diffstat (limited to 'tools/testing/selftests/net/txring_overwrite.c')
| -rw-r--r-- | tools/testing/selftests/net/txring_overwrite.c | 179 |
1 files changed, 179 insertions, 0 deletions
diff --git a/tools/testing/selftests/net/txring_overwrite.c b/tools/testing/selftests/net/txring_overwrite.c new file mode 100644 index 000000000..7d9ea0394 --- /dev/null +++ b/tools/testing/selftests/net/txring_overwrite.c @@ -0,0 +1,179 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * Verify that consecutive sends over packet tx_ring are mirrored + * with their original content intact. + */ + +#define _GNU_SOURCE + +#include <arpa/inet.h> +#include <assert.h> +#include <error.h> +#include <errno.h> +#include <fcntl.h> +#include <linux/filter.h> +#include <linux/if_packet.h> +#include <net/ethernet.h> +#include <net/if.h> +#include <netinet/in.h> +#include <netinet/ip.h> +#include <netinet/udp.h> +#include <poll.h> +#include <pthread.h> +#include <sched.h> +#include <sys/ioctl.h> +#include <sys/mman.h> +#include <sys/socket.h> +#include <sys/time.h> +#include <sys/types.h> +#include <sys/utsname.h> +#include <stdbool.h> +#include <stdint.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +const int eth_off = TPACKET_HDRLEN - sizeof(struct sockaddr_ll); +const int cfg_frame_size = 1000; + +static void build_packet(void *buffer, size_t blen, char payload_char) +{ + struct udphdr *udph; + struct ethhdr *eth; + struct iphdr *iph; + size_t off = 0; + + memset(buffer, 0, blen); + + eth = buffer; + eth->h_proto = htons(ETH_P_IP); + + off += sizeof(*eth); + iph = buffer + off; + iph->ttl = 8; + iph->ihl = 5; + iph->version = 4; + iph->saddr = htonl(INADDR_LOOPBACK); + iph->daddr = htonl(INADDR_LOOPBACK + 1); + iph->protocol = IPPROTO_UDP; + iph->tot_len = htons(blen - off); + iph->check = 0; + + off += sizeof(*iph); + udph = buffer + off; + udph->dest = htons(8000); + udph->source = htons(8001); + udph->len = htons(blen - off); + udph->check = 0; + + off += sizeof(*udph); + memset(buffer + off, payload_char, blen - off); +} + +static int setup_rx(void) +{ + int fdr; + + fdr = socket(PF_PACKET, SOCK_RAW, htons(ETH_P_IP)); + if (fdr == -1) + error(1, errno, "socket r"); + + return fdr; +} + +static int setup_tx(char **ring) +{ + struct sockaddr_ll laddr = {}; + struct tpacket_req req = {}; + int fdt; + + fdt = socket(PF_PACKET, SOCK_RAW, 0); + if (fdt == -1) + error(1, errno, "socket t"); + + laddr.sll_family = AF_PACKET; + laddr.sll_protocol = htons(0); + laddr.sll_ifindex = if_nametoindex("lo"); + if (!laddr.sll_ifindex) + error(1, errno, "if_nametoindex"); + + if (bind(fdt, (void *)&laddr, sizeof(laddr))) + error(1, errno, "bind fdt"); + + req.tp_block_size = getpagesize(); + req.tp_block_nr = 1; + req.tp_frame_size = getpagesize(); + req.tp_frame_nr = 1; + + if (setsockopt(fdt, SOL_PACKET, PACKET_TX_RING, + (void *)&req, sizeof(req))) + error(1, errno, "setsockopt ring"); + + *ring = mmap(0, req.tp_block_size * req.tp_block_nr, + PROT_READ | PROT_WRITE, MAP_SHARED, fdt, 0); + if (*ring == MAP_FAILED) + error(1, errno, "mmap"); + + return fdt; +} + +static void send_pkt(int fdt, void *slot, char payload_char) +{ + struct tpacket_hdr *header = slot; + int ret; + + while (header->tp_status != TP_STATUS_AVAILABLE) + usleep(1000); + + build_packet(slot + eth_off, cfg_frame_size, payload_char); + + header->tp_len = cfg_frame_size; + header->tp_status = TP_STATUS_SEND_REQUEST; + + ret = sendto(fdt, NULL, 0, 0, NULL, 0); + if (ret == -1) + error(1, errno, "kick tx"); +} + +static int read_verify_pkt(int fdr, char payload_char) +{ + char buf[100]; + int ret; + + ret = read(fdr, buf, sizeof(buf)); + if (ret != sizeof(buf)) + error(1, errno, "read"); + + if (buf[60] != payload_char) { + printf("wrong pattern: 0x%x != 0x%x\n", buf[60], payload_char); + return 1; + } + + printf("read: %c (0x%x)\n", buf[60], buf[60]); + return 0; +} + +int main(int argc, char **argv) +{ + const char payload_patterns[] = "ab"; + char *ring; + int fdr, fdt, ret = 0; + + fdr = setup_rx(); + fdt = setup_tx(&ring); + + send_pkt(fdt, ring, payload_patterns[0]); + send_pkt(fdt, ring, payload_patterns[1]); + + ret |= read_verify_pkt(fdr, payload_patterns[0]); + ret |= read_verify_pkt(fdr, payload_patterns[1]); + + if (close(fdt)) + error(1, errno, "close t"); + if (close(fdr)) + error(1, errno, "close r"); + + return ret; +} |