xref: /qemu/tests/unit/socket-helpers.c (revision ca61e750)
1 /*
2  * Helper functions for tests using sockets
3  *
4  * Copyright 2015-2018 Red Hat, Inc.
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License as
8  * published by the Free Software Foundation; either version 2 or
9  * (at your option) version 3 of the License.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, see <http://www.gnu.org/licenses/>.
18  *
19  */
20 
21 #include "qemu/osdep.h"
22 #include "qemu/sockets.h"
23 #include "socket-helpers.h"
24 
25 #ifndef AI_ADDRCONFIG
26 # define AI_ADDRCONFIG 0
27 #endif
28 #ifndef EAI_ADDRFAMILY
29 # define EAI_ADDRFAMILY 0
30 #endif
31 
32 /*
33  * @hostname: a DNS name or numeric IP address
34  *
35  * Check whether it is possible to bind & connect to ports
36  * on the DNS name or IP address @hostname. If an IP address
37  * is used, it must not be a wildcard address.
38  *
39  * Returns 0 on success, -1 on error with errno set
40  */
41 static int socket_can_bind_connect(const char *hostname, int family)
42 {
43     int lfd = -1, cfd = -1, afd = -1;
44     struct addrinfo ai, *res = NULL;
45     struct sockaddr_storage ss;
46     socklen_t sslen = sizeof(ss);
47     int soerr;
48     socklen_t soerrlen = sizeof(soerr);
49     bool check_soerr = false;
50     int rc;
51     int ret = -1;
52 
53     memset(&ai, 0, sizeof(ai));
54     ai.ai_flags = AI_CANONNAME | AI_ADDRCONFIG;
55     ai.ai_family = family;
56     ai.ai_socktype = SOCK_STREAM;
57 
58     /* lookup */
59     rc = getaddrinfo(hostname, NULL, &ai, &res);
60     if (rc != 0) {
61         if (rc == EAI_ADDRFAMILY || rc == EAI_FAMILY || rc == EAI_NONAME) {
62             errno = EADDRNOTAVAIL;
63         } else {
64             errno = EINVAL;
65         }
66         goto cleanup;
67     }
68 
69     lfd = qemu_socket(res->ai_family, res->ai_socktype, res->ai_protocol);
70     if (lfd < 0) {
71         goto cleanup;
72     }
73 
74     cfd = qemu_socket(res->ai_family, res->ai_socktype, res->ai_protocol);
75     if (cfd < 0) {
76         goto cleanup;
77     }
78 
79     if (bind(lfd, res->ai_addr, res->ai_addrlen) < 0) {
80         goto cleanup;
81     }
82 
83     if (listen(lfd, 1) < 0) {
84         goto cleanup;
85     }
86 
87     if (getsockname(lfd, (struct sockaddr *)&ss, &sslen) < 0) {
88         goto cleanup;
89     }
90 
91     qemu_socket_set_nonblock(cfd);
92     if (connect(cfd, (struct sockaddr *)&ss, sslen) < 0) {
93         if (errno == EINPROGRESS) {
94             check_soerr = true;
95         } else {
96             goto cleanup;
97         }
98     }
99 
100     sslen = sizeof(ss);
101     afd = accept(lfd,  (struct sockaddr *)&ss, &sslen);
102     if (afd < 0) {
103         goto cleanup;
104     }
105 
106     if (check_soerr) {
107         if (getsockopt(cfd, SOL_SOCKET, SO_ERROR, &soerr, &soerrlen) < 0) {
108             goto cleanup;
109         }
110         if (soerr) {
111             errno = soerr;
112             goto cleanup;
113         }
114     }
115 
116     ret = 0;
117 
118  cleanup:
119     if (afd != -1) {
120         close(afd);
121     }
122     if (cfd != -1) {
123         close(cfd);
124     }
125     if (lfd != -1) {
126         close(lfd);
127     }
128     if (res) {
129         freeaddrinfo(res);
130     }
131     return ret;
132 }
133 
134 
135 int socket_check_protocol_support(bool *has_ipv4, bool *has_ipv6)
136 {
137     *has_ipv4 = *has_ipv6 = false;
138 
139     if (socket_can_bind_connect("127.0.0.1", PF_INET) < 0) {
140         if (errno != EADDRNOTAVAIL) {
141             return -1;
142         }
143     } else {
144         *has_ipv4 = true;
145     }
146 
147     if (socket_can_bind_connect("::1", PF_INET6) < 0) {
148         if (errno != EADDRNOTAVAIL) {
149             return -1;
150         }
151     } else {
152         *has_ipv6 = true;
153     }
154 
155     return 0;
156 }
157