1 #include <stdlib.h>
2 #include <sys/socket.h>
3 #include <netinet/in.h>
4 #include <netdb.h>
5 #include <string.h>
6 #include <pthread.h>
7 #include <unistd.h>
8 #include <endian.h>
9 #include <errno.h>
10 #include "lookup.h"
11
getaddrinfo(const char * restrict host,const char * restrict serv,const struct addrinfo * restrict hint,struct addrinfo ** restrict res)12 int getaddrinfo(const char *restrict host, const char *restrict serv, const struct addrinfo *restrict hint, struct addrinfo **restrict res)
13 {
14 #if OHOS_DNS_PROXY_BY_NETSYS
15 if (dns_get_addr_info_from_netsys_cache(host, serv, hint, res) == 0) {
16 DNS_CONFIG_PRINT("get from netsys cache OK\n");
17 return 0;
18 }
19 #endif
20
21 struct service ports[MAXSERVS];
22 struct address addrs[MAXADDRS];
23 char canon[256], *outcanon;
24 int nservs, naddrs, nais, canon_len, i, j, k;
25 int family = AF_UNSPEC, flags = 0, proto = 0, socktype = 0;
26 struct aibuf *out;
27
28 if (!host && !serv) return EAI_NONAME;
29
30 if (hint) {
31 family = hint->ai_family;
32 flags = hint->ai_flags;
33 proto = hint->ai_protocol;
34 socktype = hint->ai_socktype;
35
36 const int mask = AI_PASSIVE | AI_CANONNAME | AI_NUMERICHOST |
37 AI_V4MAPPED | AI_ALL | AI_ADDRCONFIG | AI_NUMERICSERV;
38 if ((flags & mask) != flags)
39 return EAI_BADFLAGS;
40
41 switch (family) {
42 case AF_INET:
43 case AF_INET6:
44 case AF_UNSPEC:
45 break;
46 default:
47 return EAI_FAMILY;
48 }
49 }
50
51 if (flags & AI_ADDRCONFIG) {
52 /* Define the "an address is configured" condition for address
53 * families via ability to create a socket for the family plus
54 * routability of the loopback address for the family. */
55 static const struct sockaddr_in lo4 = {
56 .sin_family = AF_INET, .sin_port = 65535,
57 .sin_addr.s_addr = __BYTE_ORDER == __BIG_ENDIAN
58 ? 0x7f000001 : 0x0100007f
59 };
60 static const struct sockaddr_in6 lo6 = {
61 .sin6_family = AF_INET6, .sin6_port = 65535,
62 .sin6_addr = IN6ADDR_LOOPBACK_INIT
63 };
64 int tf[2] = { AF_INET, AF_INET6 };
65 const void *ta[2] = { &lo4, &lo6 };
66 socklen_t tl[2] = { sizeof lo4, sizeof lo6 };
67 for (i=0; i<2; i++) {
68 if (family==tf[1-i]) continue;
69 int s = socket(tf[i], SOCK_CLOEXEC|SOCK_DGRAM,
70 IPPROTO_UDP);
71 if (s>=0) {
72 int cs;
73 pthread_setcancelstate(
74 PTHREAD_CANCEL_DISABLE, &cs);
75 int r = connect(s, ta[i], tl[i]);
76 int saved_errno = errno;
77 pthread_setcancelstate(cs, 0);
78 close(s);
79 if (!r) continue;
80 errno = saved_errno;
81 }
82 switch (errno) {
83 case EADDRNOTAVAIL:
84 case EAFNOSUPPORT:
85 case EHOSTUNREACH:
86 case ENETDOWN:
87 case ENETUNREACH:
88 break;
89 default:
90 return EAI_SYSTEM;
91 }
92 if (family == tf[i]) return EAI_NONAME;
93 family = tf[1-i];
94 }
95 }
96
97 nservs = __lookup_serv(ports, serv, proto, socktype, flags);
98 if (nservs < 0) return nservs;
99
100 naddrs = __lookup_name(addrs, canon, host, family, flags);
101 if (naddrs < 0) return naddrs;
102
103 nais = nservs * naddrs;
104 canon_len = strlen(canon);
105 out = calloc(1, nais * sizeof(*out) + canon_len + 1);
106 if (!out) return EAI_MEMORY;
107
108 if (canon_len) {
109 outcanon = (void *)&out[nais];
110 memcpy(outcanon, canon, canon_len+1);
111 } else {
112 outcanon = 0;
113 }
114
115 for (k=i=0; i<naddrs; i++) for (j=0; j<nservs; j++, k++) {
116 out[k].slot = k;
117 out[k].ai = (struct addrinfo){
118 .ai_family = addrs[i].family,
119 .ai_socktype = ports[j].socktype,
120 .ai_protocol = ports[j].proto,
121 .ai_addrlen = addrs[i].family == AF_INET
122 ? sizeof(struct sockaddr_in)
123 : sizeof(struct sockaddr_in6),
124 .ai_addr = (void *)&out[k].sa,
125 .ai_canonname = outcanon };
126 if (k) out[k-1].ai.ai_next = &out[k].ai;
127 switch (addrs[i].family) {
128 case AF_INET:
129 out[k].sa.sin.sin_family = AF_INET;
130 out[k].sa.sin.sin_port = htons(ports[j].port);
131 memcpy(&out[k].sa.sin.sin_addr, &addrs[i].addr, 4);
132 break;
133 case AF_INET6:
134 out[k].sa.sin6.sin6_family = AF_INET6;
135 out[k].sa.sin6.sin6_port = htons(ports[j].port);
136 out[k].sa.sin6.sin6_scope_id = addrs[i].scopeid;
137 memcpy(&out[k].sa.sin6.sin6_addr, &addrs[i].addr, 16);
138 break;
139 }
140 }
141 out[0].ref = nais;
142 *res = &out->ai;
143 #if OHOS_DNS_PROXY_BY_NETSYS
144 dns_set_addr_info_to_netsys_cache(host, serv, hint, *res);
145 #endif
146 return 0;
147 }
148