xref: /xnu-11215.1.10/tests/v4mappedv6_dontfrag.c (revision 8d741a5de7ff4191bf97d57b9f54c2f6d4a15585)
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28 
29 #define __APPLE_USE_RFC_3542 1
30 
31 #include <darwintest.h>
32 
33 #include <sys/ioctl.h>
34 #include <sys/sysctl.h>
35 #include <sys/uio.h>
36 
37 #include <arpa/inet.h>
38 
39 #include <netinet/ip.h>
40 
41 #include <stdlib.h>
42 #include <string.h>
43 #include <strings.h>
44 
45 #include "net_test_lib.h"
46 
47 T_GLOBAL_META(
48 	T_META_NAMESPACE("xnu.net"),
49 	T_META_ASROOT(true),
50 	T_META_RADAR_COMPONENT_NAME("xnu"),
51 	T_META_RADAR_COMPONENT_VERSION("networking"),
52 	T_META_CHECK_LEAKS(false));
53 
54 /* need something greater than default MTU */
55 #define MAX_BUFFER_SIZE 2048
56 
57 // 169.254
58 #define LL_NET                 0xa9fe0000 //0x0a000000
59 // 169.254.1
60 #define LL_1_NET               (LL_NET | 0x000100)
61 
62 static void
get_ipv4_address(u_int unit,u_int addr_index,struct in_addr * ip)63 get_ipv4_address(u_int unit, u_int addr_index, struct in_addr *ip)
64 {
65 	/* up to 255 units, 255 addresses */
66 	ip->s_addr = htonl(LL_1_NET | (unit << 8) | addr_index);
67 	return;
68 }
69 
70 static void
network_interface_init(network_interface_t netif,const char * name,unsigned int unit,unsigned int address_index)71 network_interface_init(network_interface_t netif,
72     const char * name, unsigned int unit,
73     unsigned int address_index)
74 {
75 	network_interface_create(netif, name);
76 	get_ipv4_address(unit, address_index, &netif->ip);
77 	ifnet_add_ip_address(netif->if_name, netif->ip,
78 	    inet_class_c_subnet_mask);
79 	route_add_inet_scoped_subnet(netif->if_name, netif->if_index,
80 	    netif->ip, inet_class_c_subnet_mask);
81 }
82 
83 static network_interface if_one = {0};
84 static network_interface if_two = {0};
85 
86 static void
cleanup(void)87 cleanup(void)
88 {
89 	network_interface_destroy(&if_one);
90 	network_interface_destroy(&if_two);
91 }
92 
93 T_DECL(v4mappedv6_dontfrag_sockopt, "Tests setting IPV6_DONTFRAG on an IPv4-mapped IPv6 address")
94 {
95 	int sockfd = 0;
96 	ssize_t n;
97 	char buf[MAX_BUFFER_SIZE] = {0};
98 	struct sockaddr_in6 sin6 = {0};
99 
100 	sin6.sin6_len = sizeof(struct sockaddr_in6);
101 	sin6.sin6_family = AF_INET6;
102 	sin6.sin6_port = htons(12345);
103 
104 	T_ATEND(cleanup);
105 
106 	network_interface_init(&if_one, FETH_NAME, 0, 1);
107 	network_interface_init(&if_two, FETH_NAME, 0, 2);
108 	fake_set_peer(if_one.if_name, if_two.if_name);
109 	ifnet_set_mtu(if_one.if_name, 1500);
110 
111 	T_ASSERT_EQ(inet_pton(AF_INET6, "::ffff:169.254.1.2", &sin6.sin6_addr), 1, "inet_pton");
112 
113 	T_ASSERT_POSIX_SUCCESS(sockfd = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP), "create socket");
114 
115 	// This send should succeed (and fragment)
116 	n = sendto(sockfd, buf, MAX_BUFFER_SIZE, 0,
117 	    (struct sockaddr *)&sin6, sizeof(sin6));
118 	T_EXPECT_EQ(n, (ssize_t)MAX_BUFFER_SIZE, "Ensure we wrote MAX_BUFFER_SIZE");
119 
120 	int Option = 1;
121 	T_ASSERT_POSIX_SUCCESS(setsockopt(sockfd, IPPROTO_IPV6, IPV6_DONTFRAG, &Option, sizeof(Option)), "setsockopt IPV6_DONTFRAG to 1");
122 
123 	// This send should fail because MAX_BUFFER_SIZE > MTU and we enabled DONTFRAG
124 	n = sendto(sockfd, buf, MAX_BUFFER_SIZE, 0,
125 	    (struct sockaddr *)&sin6, sizeof(sin6));
126 	T_EXPECT_EQ(errno, EMSGSIZE, "errno should be EMSGSIZE");
127 	T_EXPECT_EQ(n, (ssize_t)-1, "Expect n of a certain size");
128 
129 	Option = 0;
130 	T_ASSERT_POSIX_SUCCESS(setsockopt(sockfd, IPPROTO_IPV6, IPV6_DONTFRAG, &Option, sizeof(Option)), "setsockopt IPV6_DONTFRAG back to 0");
131 
132 	// This send should succeeed (and fragment) because we turned the option back off
133 	n = sendto(sockfd, buf, MAX_BUFFER_SIZE, 0,
134 	    (struct sockaddr *)&sin6, sizeof(sin6));
135 	T_EXPECT_EQ(n, (ssize_t)MAX_BUFFER_SIZE, "Ensure we wrote MAX_BUFFER_SIZE");
136 }
137