Refactor existing TAP test cases to use the previously introduced tuntap_helpers from tuntap_helpers.h for device setup, packet construction, and cleanup.
This reduces code duplication, improves test maintainability, and ensures consistent behavior across test scenarios.
Signed-off-by: Xu Du xudu@redhat.com --- v1 -> v2: - Add mactap IFLA_ADDRESS attribute. - Fix incorrect argument order in build_eth and build_ipv4_header.
tools/testing/selftests/net/tap.c | 287 +++++------------------------- 1 file changed, 41 insertions(+), 246 deletions(-)
diff --git a/tools/testing/selftests/net/tap.c b/tools/testing/selftests/net/tap.c index 9ec1c9b50e77..6793e47d67a7 100644 --- a/tools/testing/selftests/net/tap.c +++ b/tools/testing/selftests/net/tap.c @@ -10,14 +10,13 @@ #include <unistd.h> #include <net/if.h> #include <linux/if_tun.h> -#include <linux/netlink.h> -#include <linux/rtnetlink.h> #include <sys/ioctl.h> #include <sys/socket.h> #include <linux/virtio_net.h> #include <netinet/ip.h> #include <netinet/udp.h> #include "kselftest_harness.h" +#include "tuntap_helpers.h"
static const char param_dev_tap_name[] = "xmacvtap0"; static const char param_dev_dummy_name[] = "xdummy0"; @@ -26,167 +25,36 @@ static unsigned char param_hwaddr_dest[] = { 0x00, 0xfe, 0x98, 0x94, 0xd2, 0x43 };
-#define MAX_RTNL_PAYLOAD (2048) -#define PKT_DATA 0xCB -#define TEST_PACKET_SZ (sizeof(struct virtio_net_hdr) + ETH_HLEN + ETH_MAX_MTU) - -static struct rtattr *rtattr_add(struct nlmsghdr *nh, unsigned short type, - unsigned short len) -{ - struct rtattr *rta = - (struct rtattr *)((uint8_t *)nh + RTA_ALIGN(nh->nlmsg_len)); - rta->rta_type = type; - rta->rta_len = RTA_LENGTH(len); - nh->nlmsg_len = RTA_ALIGN(nh->nlmsg_len) + RTA_ALIGN(rta->rta_len); - return rta; -} - -static struct rtattr *rtattr_begin(struct nlmsghdr *nh, unsigned short type) -{ - return rtattr_add(nh, type, 0); -} - -static void rtattr_end(struct nlmsghdr *nh, struct rtattr *attr) -{ - uint8_t *end = (uint8_t *)nh + nh->nlmsg_len; - - attr->rta_len = end - (uint8_t *)attr; -} - -static struct rtattr *rtattr_add_str(struct nlmsghdr *nh, unsigned short type, - const char *s) -{ - struct rtattr *rta = rtattr_add(nh, type, strlen(s)); - - memcpy(RTA_DATA(rta), s, strlen(s)); - return rta; -} - -static struct rtattr *rtattr_add_strsz(struct nlmsghdr *nh, unsigned short type, - const char *s) -{ - struct rtattr *rta = rtattr_add(nh, type, strlen(s) + 1); - - strcpy(RTA_DATA(rta), s); - return rta; -} - -static struct rtattr *rtattr_add_any(struct nlmsghdr *nh, unsigned short type, - const void *arr, size_t len) -{ - struct rtattr *rta = rtattr_add(nh, type, len); - - memcpy(RTA_DATA(rta), arr, len); - return rta; -} - -static int dev_create(const char *dev, const char *link_type, - int (*fill_rtattr)(struct nlmsghdr *nh), - int (*fill_info_data)(struct nlmsghdr *nh)) -{ - struct { - struct nlmsghdr nh; - struct ifinfomsg info; - unsigned char data[MAX_RTNL_PAYLOAD]; - } req; - struct rtattr *link_info, *info_data; - int ret, rtnl; - - rtnl = socket(AF_NETLINK, SOCK_DGRAM, NETLINK_ROUTE); - if (rtnl < 0) { - fprintf(stderr, "%s: socket %s\n", __func__, strerror(errno)); - return 1; - } - - memset(&req, 0, sizeof(req)); - req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.info)); - req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE; - req.nh.nlmsg_type = RTM_NEWLINK; - - req.info.ifi_family = AF_UNSPEC; - req.info.ifi_type = 1; - req.info.ifi_index = 0; - req.info.ifi_flags = IFF_BROADCAST | IFF_UP; - req.info.ifi_change = 0xffffffff; - - rtattr_add_str(&req.nh, IFLA_IFNAME, dev); - - if (fill_rtattr) { - ret = fill_rtattr(&req.nh); - if (ret) - return ret; - } - - link_info = rtattr_begin(&req.nh, IFLA_LINKINFO); - - rtattr_add_strsz(&req.nh, IFLA_INFO_KIND, link_type); - - if (fill_info_data) { - info_data = rtattr_begin(&req.nh, IFLA_INFO_DATA); - ret = fill_info_data(&req.nh); - if (ret) - return ret; - rtattr_end(&req.nh, info_data); - } - - rtattr_end(&req.nh, link_info); - - ret = send(rtnl, &req, req.nh.nlmsg_len, 0); - if (ret < 0) - fprintf(stderr, "%s: send %s\n", __func__, strerror(errno)); - ret = (unsigned int)ret != req.nh.nlmsg_len; - - close(rtnl); - return ret; -} - -static int dev_delete(const char *dev) -{ - struct { - struct nlmsghdr nh; - struct ifinfomsg info; - unsigned char data[MAX_RTNL_PAYLOAD]; - } req; - int ret, rtnl; - - rtnl = socket(AF_NETLINK, SOCK_DGRAM, NETLINK_ROUTE); - if (rtnl < 0) { - fprintf(stderr, "%s: socket %s\n", __func__, strerror(errno)); - return 1; - } - - memset(&req, 0, sizeof(req)); - req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.info)); - req.nh.nlmsg_flags = NLM_F_REQUEST; - req.nh.nlmsg_type = RTM_DELLINK; - - req.info.ifi_family = AF_UNSPEC; - - rtattr_add_str(&req.nh, IFLA_IFNAME, dev); +static struct in_addr param_ipaddr_src = { + __constant_htonl(0xac110002), +};
- ret = send(rtnl, &req, req.nh.nlmsg_len, 0); - if (ret < 0) - fprintf(stderr, "%s: send %s\n", __func__, strerror(errno)); +static struct in_addr param_ipaddr_dst = { + __constant_htonl(0xac110001), +};
- ret = (unsigned int)ret != req.nh.nlmsg_len; +#define UDP_SRC_PORT 22 +#define UDP_DST_PORT 58822 +#define TEST_PACKET_SZ (sizeof(struct virtio_net_hdr) + ETH_HLEN + ETH_MAX_MTU)
- close(rtnl); - return ret; -} +struct mactap_setup_config { + char name[IFNAMSIZ]; + unsigned char hwaddr[ETH_ALEN]; +};
-static int macvtap_fill_rtattr(struct nlmsghdr *nh) +static int macvtap_fill_rtattr(struct nlmsghdr *nh, void *data) { + struct mactap_setup_config *mactap = data; int ifindex;
- ifindex = if_nametoindex(param_dev_dummy_name); + ifindex = if_nametoindex(mactap->name); if (ifindex == 0) { fprintf(stderr, "%s: ifindex %s\n", __func__, strerror(errno)); return -errno; }
rtattr_add_any(nh, IFLA_LINK, &ifindex, sizeof(ifindex)); - rtattr_add_any(nh, IFLA_ADDRESS, param_hwaddr_src, ETH_ALEN); - + rtattr_add_any(nh, IFLA_ADDRESS, mactap->hwaddr, ETH_ALEN); return 0; }
@@ -218,91 +86,6 @@ static int opentap(const char *devname) return fd; }
-size_t build_eth(uint8_t *buf, uint16_t proto) -{ - struct ethhdr *eth = (struct ethhdr *)buf; - - eth->h_proto = htons(proto); - memcpy(eth->h_source, param_hwaddr_src, ETH_ALEN); - memcpy(eth->h_dest, param_hwaddr_dest, ETH_ALEN); - - return ETH_HLEN; -} - -static uint32_t add_csum(const uint8_t *buf, int len) -{ - uint32_t sum = 0; - uint16_t *sbuf = (uint16_t *)buf; - - while (len > 1) { - sum += *sbuf++; - len -= 2; - } - - if (len) - sum += *(uint8_t *)sbuf; - - return sum; -} - -static uint16_t finish_ip_csum(uint32_t sum) -{ - uint16_t lo = sum & 0xffff; - uint16_t hi = sum >> 16; - - return ~(lo + hi); - -} - -static uint16_t build_ip_csum(const uint8_t *buf, int len, - uint32_t sum) -{ - sum += add_csum(buf, len); - return finish_ip_csum(sum); -} - -static int build_ipv4_header(uint8_t *buf, int payload_len) -{ - struct iphdr *iph = (struct iphdr *)buf; - - iph->ihl = 5; - iph->version = 4; - iph->ttl = 8; - iph->tot_len = - htons(sizeof(*iph) + sizeof(struct udphdr) + payload_len); - iph->id = htons(1337); - iph->protocol = IPPROTO_UDP; - iph->saddr = htonl((172 << 24) | (17 << 16) | 2); - iph->daddr = htonl((172 << 24) | (17 << 16) | 1); - iph->check = build_ip_csum(buf, iph->ihl << 2, 0); - - return iph->ihl << 2; -} - -static int build_udp_packet(uint8_t *buf, int payload_len, bool csum_off) -{ - const int ip4alen = sizeof(uint32_t); - struct udphdr *udph = (struct udphdr *)buf; - int len = sizeof(*udph) + payload_len; - uint32_t sum = 0; - - udph->source = htons(22); - udph->dest = htons(58822); - udph->len = htons(len); - - memset(buf + sizeof(struct udphdr), PKT_DATA, payload_len); - - sum = add_csum(buf - 2 * ip4alen, 2 * ip4alen); - sum += htons(IPPROTO_UDP) + udph->len; - - if (!csum_off) - sum += add_csum(buf, len); - - udph->check = finish_ip_csum(sum); - - return sizeof(*udph) + payload_len; -} - size_t build_test_packet_valid_udp_gso(uint8_t *buf, size_t payload_len) { uint8_t *cur = buf; @@ -316,9 +99,12 @@ size_t build_test_packet_valid_udp_gso(uint8_t *buf, size_t payload_len) vh->gso_size = ETH_DATA_LEN - sizeof(struct iphdr); cur += sizeof(*vh);
- cur += build_eth(cur, ETH_P_IP); - cur += build_ipv4_header(cur, payload_len); - cur += build_udp_packet(cur, payload_len, true); + cur += build_eth(cur, ETH_P_IP, param_hwaddr_src, param_hwaddr_dest); + cur += build_ipv4_header(cur, IPPROTO_UDP, + payload_len + sizeof(struct udphdr), + ¶m_ipaddr_src, ¶m_ipaddr_dst); + cur += build_udp_packet(cur, UDP_SRC_PORT, UDP_DST_PORT, payload_len, + AF_INET, true);
return cur - buf; } @@ -332,9 +118,12 @@ size_t build_test_packet_valid_udp_csum(uint8_t *buf, size_t payload_len) vh->gso_type = VIRTIO_NET_HDR_GSO_NONE; cur += sizeof(*vh);
- cur += build_eth(cur, ETH_P_IP); - cur += build_ipv4_header(cur, payload_len); - cur += build_udp_packet(cur, payload_len, false); + cur += build_eth(cur, ETH_P_IP, param_hwaddr_src, param_hwaddr_dest); + cur += build_ipv4_header(cur, IPPROTO_UDP, + payload_len + sizeof(struct udphdr), + ¶m_ipaddr_src, ¶m_ipaddr_dst); + cur += build_udp_packet(cur, UDP_SRC_PORT, UDP_DST_PORT, payload_len, + AF_INET, false);
return cur - buf; } @@ -351,10 +140,13 @@ size_t build_test_packet_crash_tap_invalid_eth_proto(uint8_t *buf, vh->gso_size = ETH_DATA_LEN - sizeof(struct iphdr); cur += sizeof(*vh);
- cur += build_eth(cur, 0); + cur += build_eth(cur, ETH_P_IP, param_hwaddr_src, param_hwaddr_dest); cur += sizeof(struct iphdr) + sizeof(struct udphdr); - cur += build_ipv4_header(cur, payload_len); - cur += build_udp_packet(cur, payload_len, true); + cur += build_ipv4_header(cur, IPPROTO_UDP, + payload_len + sizeof(struct udphdr), + ¶m_ipaddr_src, ¶m_ipaddr_dst); + cur += build_udp_packet(cur, UDP_SRC_PORT, UDP_DST_PORT, payload_len, + AF_INET, true); cur += payload_len;
return cur - buf; @@ -368,12 +160,15 @@ FIXTURE(tap) FIXTURE_SETUP(tap) { int ret; + struct mactap_setup_config mactap_config;
- ret = dev_create(param_dev_dummy_name, "dummy", NULL, NULL); + ret = dev_create(param_dev_dummy_name, "dummy", NULL, NULL, NULL); EXPECT_EQ(ret, 0);
+ strcpy(mactap_config.name, param_dev_dummy_name); + memcpy(mactap_config.hwaddr, param_hwaddr_src, ETH_ALEN); ret = dev_create(param_dev_tap_name, "macvtap", macvtap_fill_rtattr, - NULL); + NULL, &mactap_config); EXPECT_EQ(ret, 0);
self->fd = opentap(param_dev_tap_name);