1 #include <netdb.h>
2 #include <limits.h>
3 #include <string.h>
4 #include <stdio.h>
5 #include <stdlib.h>
6 #include <sys/socket.h>
7 #include <netinet/in.h>
8 #include <arpa/inet.h>
9 #include <net/if.h>
10 #include <ctype.h>
11 #include <resolv.h>
12 #include "lookup.h"
13 #include "stdio_impl.h"
14 #include "network_conf_function.h"
15
16 #define PTR_MAX (64 + sizeof ".in-addr.arpa")
17 #define RR_PTR 12
18 #define BREAK 0
19 #define CONTINUE 1
20 #define FIXED_HOSTS_MAX_LENGTH 2
21 #define FIXED_HOSTS_STR_MAX_LENGTH 23
22
23 extern char fixed_hosts[FIXED_HOSTS_MAX_LENGTH][FIXED_HOSTS_STR_MAX_LENGTH];
24
itoa(char * p,unsigned x)25 static char *itoa(char *p, unsigned x) {
26 p += 3*sizeof(int);
27 *--p = 0;
28 do {
29 *--p = '0' + x % 10;
30 x /= 10;
31 } while (x);
32 return p;
33 }
34
mkptr4(char * s,const unsigned char * ip)35 static void mkptr4(char *s, const unsigned char *ip)
36 {
37 sprintf(s, "%d.%d.%d.%d.in-addr.arpa",
38 ip[3], ip[2], ip[1], ip[0]);
39 }
40
mkptr6(char * s,const unsigned char * ip)41 static void mkptr6(char *s, const unsigned char *ip)
42 {
43 static const char xdigits[] = "0123456789abcdef";
44 int i;
45 for (i=15; i>=0; i--) {
46 *s++ = xdigits[ip[i]&15]; *s++ = '.';
47 *s++ = xdigits[ip[i]>>4]; *s++ = '.';
48 }
49 strcpy(s, "ip6.arpa");
50 }
51
get_hosts_str(char * line,int length,FILE * f,int * i)52 static inline int get_hosts_str(char *line, int length, FILE *f, int *i)
53 {
54 if (f) {
55 return fgets(line, sizeof line, f);
56 }
57 if (*i < FIXED_HOSTS_MAX_LENGTH) {
58 memcpy(line, fixed_hosts[*i], strlen(fixed_hosts[*i]));
59 (*i)++;
60 return 1;
61 }
62 return NULL;
63 }
64
reverse_hosts(char * buf,const unsigned char * a,unsigned scopeid,int family)65 static void reverse_hosts(char *buf, const unsigned char *a, unsigned scopeid, int family)
66 {
67 char line[512], *p, *z;
68 unsigned char _buf[1032], atmp[16];
69 struct address iplit;
70 FILE _f, *f = __fopen_rb_ca("/etc/hosts", &_f, _buf, sizeof _buf);
71 if (family == AF_INET) {
72 memcpy(atmp+12, a, 4);
73 memcpy(atmp, "\0\0\0\0\0\0\0\0\0\0\xff\xff", 12);
74 a = atmp;
75 }
76 int i = 0;
77 while (i < FIXED_HOSTS_MAX_LENGTH && get_hosts_str(line, sizeof line, f, &i)) {
78 if ((p=strchr(line, '#'))) *p++='\n', *p=0;
79
80 for (p=line; *p && !isspace(*p); p++);
81 *p++ = 0;
82 if (__lookup_ipliteral(&iplit, line, AF_UNSPEC)<=0)
83 continue;
84
85 if (iplit.family == AF_INET) {
86 memcpy(iplit.addr+12, iplit.addr, 4);
87 memcpy(iplit.addr, "\0\0\0\0\0\0\0\0\0\0\xff\xff", 12);
88 iplit.scopeid = 0;
89 }
90
91 if (memcmp(a, iplit.addr, 16) || iplit.scopeid != scopeid)
92 continue;
93
94 for (; *p && isspace(*p); p++);
95 for (z=p; *z && !isspace(*z); z++);
96 *z = 0;
97 if (z-p < 256) {
98 memcpy(buf, p, z-p+1);
99 break;
100 }
101 }
102 if (f) {
103 __fclose_ca(f);
104 }
105 }
106
reverse_services(char * buf,int port,int dgram)107 static void reverse_services(char *buf, int port, int dgram)
108 {
109 unsigned long svport;
110 char line[128], *p, *z;
111 unsigned char _buf[1032];
112 FILE _f, *f = __fopen_rb_ca("/etc/services", &_f, _buf, sizeof _buf);
113 int indexPtr = 0;
114 while (get_services_str(line, f, &indexPtr)) {
115 if ((p=strchr(line, '#'))) *p++='\n', *p=0;
116
117 for (p=line; *p && !isspace(*p); p++);
118 if (!*p) continue;
119 *p++ = 0;
120 svport = strtoul(p, &z, 10);
121
122 if (svport != port || z==p) continue;
123 if (dgram && strncmp(z, "/udp", 4)) continue;
124 if (!dgram && strncmp(z, "/tcp", 4)) continue;
125 if (p-line > 32) continue;
126
127 memcpy(buf, line, p-line);
128 break;
129 }
130 if (f) {
131 __fclose_ca(f);
132 }
133 }
134
dns_parse_callback(void * c,int rr,const void * data,int len,const void * packet)135 static int dns_parse_callback(void *c, int rr, const void *data, int len, const void *packet)
136 {
137 if (rr != RR_PTR) return 0;
138 if (__dn_expand(packet, (const unsigned char *)packet + 512,
139 data, c, 256) <= 0)
140 *(char *)c = 0;
141 return 0;
142
143 }
144
getnameinfo(const struct sockaddr * restrict sa,socklen_t sl,char * restrict node,socklen_t nodelen,char * restrict serv,socklen_t servlen,int flags)145 int getnameinfo(const struct sockaddr *restrict sa, socklen_t sl,
146 char *restrict node, socklen_t nodelen,
147 char *restrict serv, socklen_t servlen,
148 int flags)
149 {
150 char ptr[PTR_MAX];
151 char buf[256], num[3*sizeof(int)+1];
152 int af = sa->sa_family;
153 unsigned char *a;
154 unsigned scopeid;
155
156 switch (af) {
157 case AF_INET:
158 a = (void *)&((struct sockaddr_in *)sa)->sin_addr;
159 if (sl < sizeof(struct sockaddr_in)) return EAI_FAMILY;
160 mkptr4(ptr, a);
161 scopeid = 0;
162 break;
163 case AF_INET6:
164 a = (void *)&((struct sockaddr_in6 *)sa)->sin6_addr;
165 if (sl < sizeof(struct sockaddr_in6)) return EAI_FAMILY;
166 if (memcmp(a, "\0\0\0\0\0\0\0\0\0\0\xff\xff", 12))
167 mkptr6(ptr, a);
168 else
169 mkptr4(ptr, a+12);
170 scopeid = ((struct sockaddr_in6 *)sa)->sin6_scope_id;
171 break;
172 default:
173 return EAI_FAMILY;
174 }
175
176 if (node && nodelen) {
177 buf[0] = 0;
178 if (!(flags & NI_NUMERICHOST)) {
179 reverse_hosts(buf, a, scopeid, af);
180 }
181 if (!*buf && !(flags & NI_NUMERICHOST)) {
182 unsigned char query[18+PTR_MAX], reply[512];
183 int qlen = __res_mkquery(0, ptr, 1, RR_PTR,
184 0, 0, 0, query, sizeof query);
185 query[3] = 0; /* don't need AD flag */
186 int rlen = __res_send(query, qlen, reply, sizeof reply);
187 buf[0] = 0;
188 if (rlen > 0)
189 __dns_parse(reply, rlen, dns_parse_callback, buf);
190 }
191 if (!*buf) {
192 if (flags & NI_NAMEREQD) return EAI_NONAME;
193 inet_ntop(af, a, buf, sizeof buf);
194 if (scopeid) {
195 char *p = 0, tmp[IF_NAMESIZE+1];
196 if (!(flags & NI_NUMERICSCOPE) &&
197 (IN6_IS_ADDR_LINKLOCAL(a) ||
198 IN6_IS_ADDR_MC_LINKLOCAL(a)))
199 p = if_indextoname(scopeid, tmp+1);
200 if (!p)
201 p = itoa(num, scopeid);
202 *--p = '%';
203 strcat(buf, p);
204 }
205 }
206 if (strlen(buf) >= nodelen) return EAI_OVERFLOW;
207 strcpy(node, buf);
208 }
209
210 if (serv && servlen) {
211 char *p = buf;
212 int port = ntohs(((struct sockaddr_in *)sa)->sin_port);
213 buf[0] = 0;
214 if (!(flags & NI_NUMERICSERV))
215 reverse_services(buf, port, flags & NI_DGRAM);
216 if (!*p)
217 p = itoa(num, port);
218 if (strlen(p) >= servlen)
219 return EAI_OVERFLOW;
220 strcpy(serv, p);
221 }
222
223 return 0;
224 }
225
226