1 | // SPDX-License-Identifier: GPL-2.0 |
2 | |
3 | /* |
4 | * Verify that consecutive sends over packet tx_ring are mirrored |
5 | * with their original content intact. |
6 | */ |
7 | |
8 | #define _GNU_SOURCE |
9 | |
10 | #include <arpa/inet.h> |
11 | #include <assert.h> |
12 | #include <error.h> |
13 | #include <errno.h> |
14 | #include <fcntl.h> |
15 | #include <linux/filter.h> |
16 | #include <linux/if_packet.h> |
17 | #include <net/ethernet.h> |
18 | #include <net/if.h> |
19 | #include <netinet/in.h> |
20 | #include <netinet/ip.h> |
21 | #include <netinet/udp.h> |
22 | #include <poll.h> |
23 | #include <pthread.h> |
24 | #include <sched.h> |
25 | #include <sys/ioctl.h> |
26 | #include <sys/mman.h> |
27 | #include <sys/socket.h> |
28 | #include <sys/time.h> |
29 | #include <sys/types.h> |
30 | #include <sys/utsname.h> |
31 | #include <stdbool.h> |
32 | #include <stdint.h> |
33 | #include <stdio.h> |
34 | #include <stdlib.h> |
35 | #include <string.h> |
36 | #include <unistd.h> |
37 | |
38 | const int eth_off = TPACKET_HDRLEN - sizeof(struct sockaddr_ll); |
39 | const int cfg_frame_size = 1000; |
40 | |
41 | static void build_packet(void *buffer, size_t blen, char payload_char) |
42 | { |
43 | struct udphdr *udph; |
44 | struct ethhdr *eth; |
45 | struct iphdr *iph; |
46 | size_t off = 0; |
47 | |
48 | memset(buffer, 0, blen); |
49 | |
50 | eth = buffer; |
51 | eth->h_proto = htons(ETH_P_IP); |
52 | |
53 | off += sizeof(*eth); |
54 | iph = buffer + off; |
55 | iph->ttl = 8; |
56 | iph->ihl = 5; |
57 | iph->version = 4; |
58 | iph->saddr = htonl(INADDR_LOOPBACK); |
59 | iph->daddr = htonl(INADDR_LOOPBACK + 1); |
60 | iph->protocol = IPPROTO_UDP; |
61 | iph->tot_len = htons(blen - off); |
62 | iph->check = 0; |
63 | |
64 | off += sizeof(*iph); |
65 | udph = buffer + off; |
66 | udph->dest = htons(8000); |
67 | udph->source = htons(8001); |
68 | udph->len = htons(blen - off); |
69 | udph->check = 0; |
70 | |
71 | off += sizeof(*udph); |
72 | memset(buffer + off, payload_char, blen - off); |
73 | } |
74 | |
75 | static int setup_rx(void) |
76 | { |
77 | int fdr; |
78 | |
79 | fdr = socket(PF_PACKET, SOCK_RAW, htons(ETH_P_IP)); |
80 | if (fdr == -1) |
81 | error(1, errno, "socket r" ); |
82 | |
83 | return fdr; |
84 | } |
85 | |
86 | static int setup_tx(char **ring) |
87 | { |
88 | struct sockaddr_ll laddr = {}; |
89 | struct tpacket_req req = {}; |
90 | int fdt; |
91 | |
92 | fdt = socket(PF_PACKET, SOCK_RAW, 0); |
93 | if (fdt == -1) |
94 | error(1, errno, "socket t" ); |
95 | |
96 | laddr.sll_family = AF_PACKET; |
97 | laddr.sll_protocol = htons(0); |
98 | laddr.sll_ifindex = if_nametoindex("lo" ); |
99 | if (!laddr.sll_ifindex) |
100 | error(1, errno, "if_nametoindex" ); |
101 | |
102 | if (bind(fdt, (void *)&laddr, sizeof(laddr))) |
103 | error(1, errno, "bind fdt" ); |
104 | |
105 | req.tp_block_size = getpagesize(); |
106 | req.tp_block_nr = 1; |
107 | req.tp_frame_size = getpagesize(); |
108 | req.tp_frame_nr = 1; |
109 | |
110 | if (setsockopt(fdt, SOL_PACKET, PACKET_TX_RING, |
111 | (void *)&req, sizeof(req))) |
112 | error(1, errno, "setsockopt ring" ); |
113 | |
114 | *ring = mmap(0, req.tp_block_size * req.tp_block_nr, |
115 | PROT_READ | PROT_WRITE, MAP_SHARED, fdt, 0); |
116 | if (*ring == MAP_FAILED) |
117 | error(1, errno, "mmap" ); |
118 | |
119 | return fdt; |
120 | } |
121 | |
122 | static void send_pkt(int fdt, void *slot, char payload_char) |
123 | { |
124 | struct tpacket_hdr * = slot; |
125 | int ret; |
126 | |
127 | while (header->tp_status != TP_STATUS_AVAILABLE) |
128 | usleep(1000); |
129 | |
130 | build_packet(buffer: slot + eth_off, blen: cfg_frame_size, payload_char); |
131 | |
132 | header->tp_len = cfg_frame_size; |
133 | header->tp_status = TP_STATUS_SEND_REQUEST; |
134 | |
135 | ret = sendto(fdt, NULL, 0, 0, NULL, 0); |
136 | if (ret == -1) |
137 | error(1, errno, "kick tx" ); |
138 | } |
139 | |
140 | static int read_verify_pkt(int fdr, char payload_char) |
141 | { |
142 | char buf[100]; |
143 | int ret; |
144 | |
145 | ret = read(fdr, buf, sizeof(buf)); |
146 | if (ret != sizeof(buf)) |
147 | error(1, errno, "read" ); |
148 | |
149 | if (buf[60] != payload_char) { |
150 | printf("wrong pattern: 0x%x != 0x%x\n" , buf[60], payload_char); |
151 | return 1; |
152 | } |
153 | |
154 | printf("read: %c (0x%x)\n" , buf[60], buf[60]); |
155 | return 0; |
156 | } |
157 | |
158 | int main(int argc, char **argv) |
159 | { |
160 | const char payload_patterns[] = "ab" ; |
161 | char *ring; |
162 | int fdr, fdt, ret = 0; |
163 | |
164 | fdr = setup_rx(); |
165 | fdt = setup_tx(&ring); |
166 | |
167 | send_pkt(fdt, slot: ring, payload_char: payload_patterns[0]); |
168 | send_pkt(fdt, slot: ring, payload_char: payload_patterns[1]); |
169 | |
170 | ret |= read_verify_pkt(fdr, payload_char: payload_patterns[0]); |
171 | ret |= read_verify_pkt(fdr, payload_char: payload_patterns[1]); |
172 | |
173 | if (close(fdt)) |
174 | error(1, errno, "close t" ); |
175 | if (close(fdr)) |
176 | error(1, errno, "close r" ); |
177 | |
178 | return ret; |
179 | } |
180 | |