/*-*- 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-resolve.h" #include "resolve-util.h" #include "macro.h" int main(int argc, char *argv[]) { int r = 1; _cleanup_resolve_unref_ sd_resolve *resolve = NULL; _cleanup_resolve_addrinfo_free_ struct addrinfo *ai = NULL; _cleanup_free_ unsigned char *srv = NULL; sd_resolve_query *q1 = NULL, *q2 = NULL, *q3 = NULL; struct addrinfo hints = {}; struct sockaddr_in sa = {}; _cleanup_free_ char *host = NULL, *serv = NULL; assert_se(sd_resolve_new(&resolve) >= 0); /* Make a name -> address query */ hints.ai_family = PF_UNSPEC; hints.ai_socktype = SOCK_STREAM; hints.ai_flags = AI_CANONNAME; r = sd_resolve_getaddrinfo(resolve, &q1, argc >= 2 ? argv[1] : "www.heise.de", NULL, &hints); if (r < 0) log_error("sd_resolve_getaddrinfo(): %s\n", strerror(-r)); /* 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); r = sd_resolve_getnameinfo(resolve, &q2, (struct sockaddr*) &sa, sizeof(sa), 0, true, true); if (r < 0) log_error("sd_resolve_getnameinfo(): %s\n", strerror(-r)); /* Make a res_query() call */ r = sd_resolve_res_query(resolve, &q3, "_xmpp-client._tcp.gmail.com", C_IN, T_SRV); if (r < 0) log_error("sd_resolve_res_query(): %s\n", strerror(-r)); /* Wait until the three queries are completed */ while (sd_resolve_is_done(q1) == 0 || sd_resolve_is_done(q2) == 0 || sd_resolve_is_done(q3) == 0) { r = sd_resolve_wait(resolve, (uint64_t) -1); if (r < 0) { log_error("sd_resolve_wait(): %s\n", strerror(-r)); assert_not_reached("sd_resolve_wait() failed"); } } /* Interpret the result of the name -> addr query */ r = sd_resolve_getaddrinfo_done(q1, &ai); if (r != 0) log_error("error: %s %i\n", gai_strerror(r), r); 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); } printf("canonical name: %s\n", strna(ai->ai_canonname)); } /* Interpret the result of the addr -> name query */ r = sd_resolve_getnameinfo_done(q2, &host, &serv); if (r) log_error("error: %s %i\n", gai_strerror(r), r); else printf("%s -- %s\n", host, serv); /* Interpret the result of the SRV lookup */ r = sd_resolve_res_done(q3, &srv); if (r < 0) log_error("error: %s %i\n", strerror(-r), r); else if (r == 0) log_error("No reply for SRV lookup\n"); else { int qdcount; int ancount; int len; const unsigned char *pos = srv + sizeof(HEADER); unsigned char *end = srv + r; 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; }