/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ /*** This file is part of systemd. Copyright 2005-2008 Lennart Poettering systemd is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. systemd is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with systemd; If not, see . ***/ #include #include #include #include #include #include #include #include #include #include #include #include "sd-dns.h" #include "dns-util.h" #include "macro.h" int main(int argc, char *argv[]) { int r = 1, ret; _cleanup_asyncns_free_ asyncns_t *asyncns = NULL; _cleanup_asyncns_addrinfo_free_ struct addrinfo *ai = NULL; _cleanup_asyncns_answer_free_ unsigned char *srv = NULL; asyncns_query_t *q1, *q2, *q3; struct addrinfo hints = {}; struct sockaddr_in sa = {}; char host[NI_MAXHOST] = "", serv[NI_MAXSERV] = ""; signal(SIGCHLD, SIG_IGN); asyncns = asyncns_new(2); if (!asyncns) log_oom(); /* Make a name -> address query */ hints.ai_family = PF_UNSPEC; hints.ai_socktype = SOCK_STREAM; q1 = asyncns_getaddrinfo(asyncns, argc >= 2 ? argv[1] : "www.heise.de", NULL, &hints); if (!q1) fprintf(stderr, "asyncns_getaddrinfo(): %s\n", strerror(errno)); /* Make an address -> name query */ sa.sin_family = AF_INET; sa.sin_addr.s_addr = inet_addr(argc >= 3 ? argv[2] : "193.99.144.71"); sa.sin_port = htons(80); q2 = asyncns_getnameinfo(asyncns, (struct sockaddr*) &sa, sizeof(sa), 0, 1, 1); if (!q2) fprintf(stderr, "asyncns_getnameinfo(): %s\n", strerror(errno)); /* Make a res_query() call */ q3 = asyncns_res_query(asyncns, "_xmpp-client._tcp.gmail.com", C_IN, T_SRV); if (!q3) fprintf(stderr, "asyncns_res_query(): %s\n", strerror(errno)); /* Wait until the three queries are completed */ while (!asyncns_isdone(asyncns, q1) || !asyncns_isdone(asyncns, q2) || !asyncns_isdone(asyncns, q3)) { if (asyncns_wait(asyncns, 1) < 0) { fprintf(stderr, "asyncns_wait(): %s\n", strerror(errno)); } } /* Interpret the result of the name -> addr query */ if ((ret = asyncns_getaddrinfo_done(asyncns, q1, &ai))) fprintf(stderr, "error: %s %i\n", gai_strerror(ret), ret); else { struct addrinfo *i; for (i = ai; i; i = i->ai_next) { char t[256]; const char *p = NULL; if (i->ai_family == PF_INET) p = inet_ntop(AF_INET, &((struct sockaddr_in*) i->ai_addr)->sin_addr, t, sizeof(t)); else if (i->ai_family == PF_INET6) p = inet_ntop(AF_INET6, &((struct sockaddr_in6*) i->ai_addr)->sin6_addr, t, sizeof(t)); printf("%s\n", p); } } /* Interpret the result of the addr -> name query */ if ((ret = asyncns_getnameinfo_done(asyncns, q2, host, sizeof(host), serv, sizeof(serv)))) fprintf(stderr, "error: %s %i\n", gai_strerror(ret), ret); else printf("%s -- %s\n", host, serv); /* Interpret the result of the SRV lookup */ if ((ret = asyncns_res_done(asyncns, q3, &srv)) < 0) { fprintf(stderr, "error: %s %i\n", strerror(errno), ret); } else if (ret == 0) { fprintf(stderr, "No reply for SRV lookup\n"); } else { int qdcount; int ancount; int len; const unsigned char *pos = srv + sizeof(HEADER); unsigned char *end = srv + ret; HEADER *head = (HEADER *)srv; char name[256]; qdcount = ntohs(head->qdcount); ancount = ntohs(head->ancount); printf("%d answers for srv lookup:\n", ancount); /* Ignore the questions */ while (qdcount-- > 0 && (len = dn_expand(srv, end, pos, name, 255)) >= 0) { assert(len >= 0); pos += len + QFIXEDSZ; } /* Parse the answers */ while (ancount-- > 0 && (len = dn_expand(srv, end, pos, name, 255)) >= 0) { /* Ignore the initial string */ uint16_t pref, weight, port; assert(len >= 0); pos += len; /* Ignore type, ttl, class and dlen */ pos += 10; GETSHORT(pref, pos); GETSHORT(weight, pos); GETSHORT(port, pos); len = dn_expand(srv, end, pos, name, 255); printf("\tpreference: %2d weight: %2d port: %d host: %s\n", pref, weight, port, name); pos += len; } } r = 0; return r; }