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24#define FOR_host
25#include "toys.h"
26
27GLOBALS(
28 char *type_str;
29)
30
31#include <resolv.h>
32
33#define PL_IP 1
34#define PL_NAME 2
35#define PL_DATA 3
36#define PL_TEXT 4
37#define PL_SOA 5
38#define PL_MX 6
39#define PL_SRV 7
40
41static const struct rrt {
42 const char *name;
43 const char *msg;
44 int pl;
45 int af;
46} rrt[] = {
47 [1] = { "A", "has address", PL_IP, AF_INET },
48 [28] = { "AAAA", "has address", PL_IP, AF_INET6 },
49 [2] = { "NS", "name server", PL_NAME },
50 [5] = { "CNAME", "is a nickname for", PL_NAME },
51 [16] = { "TXT", "descriptive text", PL_TEXT },
52 [6] = { "SOA", "start of authority", PL_SOA },
53 [12] = { "PTR", "domain name pointer", PL_NAME },
54 [15] = { "MX", "mail is handled", PL_MX },
55 [33] = { "SRV", "mail is handled", PL_SRV },
56 [255] = { "*", 0, 0 },
57};
58
59static const char rct[16][32] = {
60 "Success",
61 "Format error",
62 "Server failure",
63 "Non-existant domain",
64 "Not implemented",
65 "Refused",
66};
67
68void host_main(void)
69{
70 int verbose=(toys.optflags & (FLAG_a|FLAG_v)), type,
71 i, j, ret, sec, count, rcode, qlen, alen, pllen = 0,
72 abuf_len = 65536;
73 unsigned ttl, pri, v[5];
74 unsigned char *abuf = xmalloc(abuf_len);
75 char *rrname = xmalloc(MAXDNAME);
76 unsigned char qbuf[280], *p;
77 char *name, *nsname, plname[640], ptrbuf[128];
78 struct addrinfo *ai, iplit_hints = { .ai_flags = AI_NUMERICHOST };
79
80 name = *toys.optargs;
81 nsname = toys.optargs[1];
82
83 if (!TT.type_str && (toys.optflags & FLAG_a)) TT.type_str = "255";
84 if (!getaddrinfo(name, 0, &iplit_hints, &ai)) {
85 unsigned char *a;
86 static const char xdigits[] = "0123456789abcdef";
87
88 if (ai->ai_family == AF_INET) {
89 a = (void *)&((struct sockaddr_in *)ai->ai_addr)->sin_addr;
90 snprintf(ptrbuf, sizeof(ptrbuf), "%d.%d.%d.%d.in-addr.arpa",
91 a[3], a[2], a[1], a[0]);
92 } else if (ai->ai_family == AF_INET6) {
93 a = (void *)&((struct sockaddr_in6 *)ai->ai_addr)->sin6_addr;
94 for (j=0, i=15; i>=0; i--) {
95 ptrbuf[j++] = xdigits[a[i]&15];
96 ptrbuf[j++] = '.';
97 ptrbuf[j++] = xdigits[a[i]>>4];
98 ptrbuf[j++] = '.';
99 }
100 strcpy(ptrbuf+j, "ip6.arpa");
101 }
102 name = ptrbuf;
103 if (!TT.type_str) TT.type_str="12";
104 } else if (!TT.type_str) TT.type_str="1";
105
106 if (TT.type_str[0]-'0' < 10u) type = atoi(TT.type_str);
107 else {
108 type = -1;
109 for (i=0; i<ARRAY_LEN(rrt); i++) {
110 if (rrt[i].name && !strcasecmp(TT.type_str, rrt[i].name)) {
111 type = i;
112 break;
113 }
114 }
115 if (!strcasecmp(TT.type_str, "any")) type = 255;
116 if (type < 0) error_exit("Invalid query type: %s", TT.type_str);
117 }
118
119 qlen = res_mkquery(0, name, 1, type, 0, 0, 0, qbuf, sizeof(qbuf));
120 if (qlen < 0) error_exit("Invalid query parameters: %s", name);
121
122 if (nsname) {
123 struct addrinfo ns_hints = { .ai_socktype = SOCK_DGRAM };
124
125 if ((ret = getaddrinfo(nsname, "53", &ns_hints, &ai)) < 0)
126 error_exit("Error looking up server name: %s", gai_strerror(ret));
127 int s = xsocket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
128 xconnect(s, ai->ai_addr, ai->ai_addrlen);
129 setsockopt(s, SOL_SOCKET, SO_RCVTIMEO, &(struct timeval){ .tv_sec = 5 },
130 sizeof(struct timeval));
131 printf("Using domain server %s:\n", nsname);
132 send(s, qbuf, qlen, 0);
133 alen = recv(s, abuf, abuf_len, 0);
134 } else alen = res_send(qbuf, qlen, abuf, abuf_len);
135
136 if (alen < 12) error_exit("Host not found.");
137
138 rcode = abuf[3] & 15;
139
140 if (verbose) {
141 printf("rcode = %d (%s), ancount = %d\n",
142 rcode, rct[rcode], 256*abuf[6] + abuf[7]);
143 if (!(abuf[2] & 4)) printf("The following answer is not authoritative:\n");
144 }
145
146 if (rcode) error_exit("Host not found.");
147
148 p = abuf + 12;
149 for (sec=0; sec<4; sec++) {
150 count = 256*abuf[4+2*sec] + abuf[5+2*sec];
151 if (verbose && count>0 && sec>1)
152 puts(sec==2 ? "For authoritative answers, see:"
153 : "Additional information:");
154
155 for (; count--; p += pllen) {
156 p += dn_expand(abuf, abuf+alen, p, rrname, MAXDNAME);
157 type = (p[0]<<8) + p[1];
158 p += 4;
159 if (!sec) continue;
160 ttl = (p[0]<<24)+(p[1]<<16)+(p[2]<<8)+p[3];
161 p += 4;
162 pllen = (p[0]<<8) + p[1];
163 p += 2;
164
165 switch (type<ARRAY_LEN(rrt) ? rrt[type].pl : 0) {
166 case PL_IP:
167 inet_ntop(rrt[type].af, p, plname, sizeof(plname));
168 break;
169 case PL_NAME:
170 dn_expand(abuf, abuf+alen, p, plname, sizeof(plname));
171 break;
172 case PL_TEXT:
173 snprintf(plname, sizeof(plname), "\"%.*s\"", pllen, p);
174 break;
175 case PL_SOA:
176 i = dn_expand(abuf, abuf+alen, p, plname, sizeof(plname) - 1);
177 strcat(plname, " ");
178 i += dn_expand(abuf, abuf+alen, p+i, plname+strlen(plname),
179 sizeof(plname)-strlen(plname));
180 for (j=0; j<5; j++)
181 v[j] = (p[i+4*j]<<24)+(p[1+i+4*j]<<16)+(p[2+i+4*j]<<8)+p[3+i+4*j];
182 snprintf(plname+strlen(plname), sizeof(plname)-strlen(plname),
183 "(\n\t\t%u\t;serial (version)\n"
184 "\t\t%u\t;refresh period\n"
185 "\t\t%u\t;retry interval\n"
186 "\t\t%u\t;expire time\n"
187 "\t\t%u\t;default ttl\n"
188 "\t\t)", v[0], v[1], v[2], v[3], v[4]);
189 break;
190 case PL_MX:
191 pri = (p[0]<<8)+p[1];
192 snprintf(plname, sizeof(plname), verbose ? "%d " : "(pri=%d) by ", pri);
193 dn_expand(abuf, abuf+alen, p+2, plname+strlen(plname),
194 sizeof(plname) - strlen(plname));
195 break;
196 case PL_SRV:
197 for (j=0; j<3; j++) v[j] = (p[2*j]<<8) + p[1+2*j];
198 snprintf(plname, sizeof(plname), "%u %u %u ", v[0], v[1], v[2]);
199 dn_expand(abuf, abuf+alen, p+6, plname+strlen(plname),
200 sizeof(plname) - strlen(plname));
201 break;
202 default:
203 printf("%s unsupported RR type %u\n", rrname, type);
204 continue;
205 }
206
207 if (verbose)
208 printf("%s\t%u\tIN %s\t%s\n", rrname, ttl, rrt[type].name, plname);
209 else if (rrt[type].msg)
210 printf("%s %s %s\n", rrname, rrt[type].msg, plname);
211 }
212 if (!verbose && sec==1) break;
213 }
214
215 if (CFG_TOYBOX_FREE) {
216 free(abuf);
217 free(rrname);
218 }
219 toys.exitval = rcode;
220}
221
