/*-*- 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 #include #include #include #include #include #include #include #include #include #include #include "util.h" #include "list.h" #include "socket-util.h" #include "missing.h" #include "resolve-util.h" #include "sd-resolve.h" #define WORKERS_MIN 1U #define WORKERS_MAX 16U #define QUERIES_MAX 256U #define BUFSIZE 10240U typedef enum { REQUEST_ADDRINFO, RESPONSE_ADDRINFO, REQUEST_NAMEINFO, RESPONSE_NAMEINFO, REQUEST_RES_QUERY, REQUEST_RES_SEARCH, RESPONSE_RES, REQUEST_TERMINATE, RESPONSE_DIED } QueryType; enum { REQUEST_RECV_FD, REQUEST_SEND_FD, RESPONSE_RECV_FD, RESPONSE_SEND_FD, _FD_MAX }; struct sd_resolve { unsigned n_ref; bool dead:1; pid_t original_pid; int fds[_FD_MAX]; pthread_t workers[WORKERS_MAX]; unsigned n_valid_workers; unsigned current_id, current_index; sd_resolve_query* queries[QUERIES_MAX]; unsigned n_queries, n_done; sd_event_source *event_source; sd_event *event; sd_resolve_query *current; sd_resolve **default_resolve_ptr; pid_t tid; }; struct sd_resolve_query { unsigned n_ref; sd_resolve *resolve; QueryType type:4; bool done:1; unsigned id; int ret; int _errno; int _h_errno; struct addrinfo *addrinfo; char *serv, *host; unsigned char *answer; union { sd_resolve_getaddrinfo_handler_t getaddrinfo_handler; sd_resolve_getnameinfo_handler_t getnameinfo_handler; sd_resolve_res_handler_t res_handler; }; void *userdata; }; typedef struct RHeader { QueryType type; unsigned id; size_t length; } RHeader; typedef struct AddrInfoRequest { struct RHeader header; bool hints_valid; int ai_flags; int ai_family; int ai_socktype; int ai_protocol; size_t node_len, service_len; } AddrInfoRequest; typedef struct AddrInfoResponse { struct RHeader header; int ret; int _errno; int _h_errno; /* followed by addrinfo_serialization[] */ } AddrInfoResponse; typedef struct AddrInfoSerialization { int ai_flags; int ai_family; int ai_socktype; int ai_protocol; size_t ai_addrlen; size_t canonname_len; /* Followed by ai_addr amd ai_canonname with variable lengths */ } AddrInfoSerialization; typedef struct NameInfoRequest { struct RHeader header; int flags; socklen_t sockaddr_len; bool gethost:1, getserv:1; } NameInfoRequest; typedef struct NameInfoResponse { struct RHeader header; size_t hostlen, servlen; int ret; int _errno; int _h_errno; } NameInfoResponse; typedef struct ResRequest { struct RHeader header; int class; int type; size_t dname_len; } ResRequest; typedef struct ResResponse { struct RHeader header; int ret; int _errno; int _h_errno; } ResResponse; typedef union Packet { RHeader rheader; AddrInfoRequest addrinfo_request; AddrInfoResponse addrinfo_response; NameInfoRequest nameinfo_request; NameInfoResponse nameinfo_response; ResRequest res_request; ResResponse res_response; } Packet; static int getaddrinfo_done(sd_resolve_query* q); static int getnameinfo_done(sd_resolve_query *q); static int res_query_done(sd_resolve_query* q); #define RESOLVE_DONT_DESTROY(resolve) \ _cleanup_resolve_unref_ _unused_ sd_resolve *_dont_destroy_##resolve = sd_resolve_ref(resolve) static int send_died(int out_fd) { RHeader rh = { .type = RESPONSE_DIED, .length = sizeof(RHeader), }; assert(out_fd >= 0); if (send(out_fd, &rh, rh.length, MSG_NOSIGNAL) < 0) return -errno; return 0; } static void *serialize_addrinfo(void *p, const struct addrinfo *ai, size_t *length, size_t maxlength) { AddrInfoSerialization s; size_t cnl, l; assert(p); assert(ai); assert(length); assert(*length <= maxlength); cnl = ai->ai_canonname ? strlen(ai->ai_canonname)+1 : 0; l = sizeof(AddrInfoSerialization) + ai->ai_addrlen + cnl; if (*length + l > maxlength) return NULL; s.ai_flags = ai->ai_flags; s.ai_family = ai->ai_family; s.ai_socktype = ai->ai_socktype; s.ai_protocol = ai->ai_protocol; s.ai_addrlen = ai->ai_addrlen; s.canonname_len = cnl; memcpy((uint8_t*) p, &s, sizeof(AddrInfoSerialization)); memcpy((uint8_t*) p + sizeof(AddrInfoSerialization), ai->ai_addr, ai->ai_addrlen); if (ai->ai_canonname) memcpy((char*) p + sizeof(AddrInfoSerialization) + ai->ai_addrlen, ai->ai_canonname, cnl); *length += l; return (uint8_t*) p + l; } static int send_addrinfo_reply( int out_fd, unsigned id, int ret, struct addrinfo *ai, int _errno, int _h_errno) { AddrInfoResponse resp = { .header.type = RESPONSE_ADDRINFO, .header.id = id, .header.length = sizeof(AddrInfoResponse), .ret = ret, ._errno = _errno, ._h_errno = _h_errno, }; struct msghdr mh = {}; struct iovec iov[2]; union { AddrInfoSerialization ais; uint8_t space[BUFSIZE]; } buffer; assert(out_fd >= 0); if (ret == 0 && ai) { void *p = &buffer; struct addrinfo *k; for (k = ai; k; k = k->ai_next) { p = serialize_addrinfo(p, k, &resp.header.length, (uint8_t*) &buffer + BUFSIZE - (uint8_t*) p); if (!p) { freeaddrinfo(ai); return -ENOBUFS; } } } if (ai) freeaddrinfo(ai); iov[0] = (struct iovec) { .iov_base = &resp, .iov_len = sizeof(AddrInfoResponse) }; iov[1] = (struct iovec) { .iov_base = &buffer, .iov_len = resp.header.length - sizeof(AddrInfoResponse) }; mh.msg_iov = iov; mh.msg_iovlen = ELEMENTSOF(iov); if (sendmsg(out_fd, &mh, MSG_NOSIGNAL) < 0) return -errno; return 0; } static int send_nameinfo_reply( int out_fd, unsigned id, int ret, const char *host, const char *serv, int _errno, int _h_errno) { NameInfoResponse resp = { .header.type = RESPONSE_NAMEINFO, .header.id = id, .ret = ret, ._errno = _errno, ._h_errno = _h_errno, }; struct msghdr mh = {}; struct iovec iov[3]; size_t hl, sl; assert(out_fd >= 0); sl = serv ? strlen(serv)+1 : 0; hl = host ? strlen(host)+1 : 0; resp.header.length = sizeof(NameInfoResponse) + hl + sl; resp.hostlen = hl; resp.servlen = sl; iov[0] = (struct iovec) { .iov_base = &resp, .iov_len = sizeof(NameInfoResponse) }; iov[1] = (struct iovec) { .iov_base = (void*) host, .iov_len = hl }; iov[2] = (struct iovec) { .iov_base = (void*) serv, .iov_len = sl }; mh.msg_iov = iov; mh.msg_iovlen = ELEMENTSOF(iov); if (sendmsg(out_fd, &mh, MSG_NOSIGNAL) < 0) return -errno; return 0; } static int send_res_reply(int out_fd, unsigned id, const unsigned char *answer, int ret, int _errno, int _h_errno) { ResResponse resp = { .header.type = RESPONSE_RES, .header.id = id, .ret = ret, ._errno = _errno, ._h_errno = _h_errno, }; struct msghdr mh = {}; struct iovec iov[2]; size_t l; assert(out_fd >= 0); l = ret > 0 ? (size_t) ret : 0; resp.header.length = sizeof(ResResponse) + l; iov[0] = (struct iovec) { .iov_base = &resp, .iov_len = sizeof(ResResponse) }; iov[1] = (struct iovec) { .iov_base = (void*) answer, .iov_len = l }; mh.msg_iov = iov; mh.msg_iovlen = ELEMENTSOF(iov); if (sendmsg(out_fd, &mh, MSG_NOSIGNAL) < 0) return -errno; return 0; } static int handle_request(int out_fd, const Packet *packet, size_t length) { const RHeader *req; assert(out_fd >= 0); assert(packet); req = &packet->rheader; assert(length >= sizeof(RHeader)); assert(length == req->length); switch (req->type) { case REQUEST_ADDRINFO: { const AddrInfoRequest *ai_req = &packet->addrinfo_request; struct addrinfo hints = {}, *result = NULL; const char *node, *service; int ret; assert(length >= sizeof(AddrInfoRequest)); assert(length == sizeof(AddrInfoRequest) + ai_req->node_len + ai_req->service_len); hints.ai_flags = ai_req->ai_flags; hints.ai_family = ai_req->ai_family; hints.ai_socktype = ai_req->ai_socktype; hints.ai_protocol = ai_req->ai_protocol; node = ai_req->node_len ? (const char*) ai_req + sizeof(AddrInfoRequest) : NULL; service = ai_req->service_len ? (const char*) ai_req + sizeof(AddrInfoRequest) + ai_req->node_len : NULL; ret = getaddrinfo( node, service, ai_req->hints_valid ? &hints : NULL, &result); /* send_addrinfo_reply() frees result */ return send_addrinfo_reply(out_fd, req->id, ret, result, errno, h_errno); } case REQUEST_NAMEINFO: { const NameInfoRequest *ni_req = &packet->nameinfo_request; char hostbuf[NI_MAXHOST], servbuf[NI_MAXSERV]; union sockaddr_union sa; int ret; assert(length >= sizeof(NameInfoRequest)); assert(length == sizeof(NameInfoRequest) + ni_req->sockaddr_len); assert(sizeof(sa) >= ni_req->sockaddr_len); memcpy(&sa, (const uint8_t *) ni_req + sizeof(NameInfoRequest), ni_req->sockaddr_len); ret = getnameinfo(&sa.sa, ni_req->sockaddr_len, ni_req->gethost ? hostbuf : NULL, ni_req->gethost ? sizeof(hostbuf) : 0, ni_req->getserv ? servbuf : NULL, ni_req->getserv ? sizeof(servbuf) : 0, ni_req->flags); return send_nameinfo_reply(out_fd, req->id, ret, ret == 0 && ni_req->gethost ? hostbuf : NULL, ret == 0 && ni_req->getserv ? servbuf : NULL, errno, h_errno); } case REQUEST_RES_QUERY: case REQUEST_RES_SEARCH: { const ResRequest *res_req = &packet->res_request; union { HEADER header; uint8_t space[BUFSIZE]; } answer; const char *dname; int ret; assert(length >= sizeof(ResRequest)); assert(length == sizeof(ResRequest) + res_req->dname_len); dname = (const char *) req + sizeof(ResRequest); if (req->type == REQUEST_RES_QUERY) ret = res_query(dname, res_req->class, res_req->type, (unsigned char *) &answer, BUFSIZE); else ret = res_search(dname, res_req->class, res_req->type, (unsigned char *) &answer, BUFSIZE); return send_res_reply(out_fd, req->id, (unsigned char *) &answer, ret, errno, h_errno); } case REQUEST_TERMINATE: /* Quit */ return -ECONNRESET; default: assert_not_reached("Unknown request"); } return 0; } static void* thread_worker(void *p) { sd_resolve *resolve = p; sigset_t fullset; /* No signals in this thread please */ assert_se(sigfillset(&fullset) == 0); assert_se(pthread_sigmask(SIG_BLOCK, &fullset, NULL) == 0); /* Assign a pretty name to this thread */ prctl(PR_SET_NAME, (unsigned long) "sd-resolve"); while (!resolve->dead) { union { Packet packet; uint8_t space[BUFSIZE]; } buf; ssize_t length; length = recv(resolve->fds[REQUEST_RECV_FD], &buf, sizeof(buf), 0); if (length < 0) { if (errno == EINTR) continue; break; } if (length == 0) break; if (resolve->dead) break; if (handle_request(resolve->fds[RESPONSE_SEND_FD], &buf.packet, (size_t) length) < 0) break; } send_died(resolve->fds[RESPONSE_SEND_FD]); return NULL; } static int start_threads(sd_resolve *resolve, unsigned extra) { unsigned n; int r; n = resolve->n_queries + extra - resolve->n_done; n = CLAMP(n, WORKERS_MIN, WORKERS_MAX); while (resolve->n_valid_workers < n) { r = pthread_create(&resolve->workers[resolve->n_valid_workers], NULL, thread_worker, resolve); if (r != 0) return -r; resolve->n_valid_workers ++; } return 0; } static bool resolve_pid_changed(sd_resolve *r) { assert(r); /* We don't support people creating a resolver and keeping it * around after fork(). Let's complain. */ return r->original_pid != getpid(); } _public_ int sd_resolve_new(sd_resolve **ret) { sd_resolve *resolve = NULL; int i, r; assert_return(ret, -EINVAL); resolve = new0(sd_resolve, 1); if (!resolve) return -ENOMEM; resolve->n_ref = 1; resolve->original_pid = getpid(); for (i = 0; i < _FD_MAX; i++) resolve->fds[i] = -1; r = socketpair(PF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0, resolve->fds + REQUEST_RECV_FD); if (r < 0) { r = -errno; goto fail; } r = socketpair(PF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0, resolve->fds + RESPONSE_RECV_FD); if (r < 0) { r = -errno; goto fail; } fd_inc_sndbuf(resolve->fds[REQUEST_SEND_FD], QUERIES_MAX * BUFSIZE); fd_inc_rcvbuf(resolve->fds[REQUEST_RECV_FD], QUERIES_MAX * BUFSIZE); fd_inc_sndbuf(resolve->fds[RESPONSE_SEND_FD], QUERIES_MAX * BUFSIZE); fd_inc_rcvbuf(resolve->fds[RESPONSE_RECV_FD], QUERIES_MAX * BUFSIZE); fd_nonblock(resolve->fds[RESPONSE_RECV_FD], true); *ret = resolve; return 0; fail: sd_resolve_unref(resolve); return r; } _public_ int sd_resolve_default(sd_resolve **ret) { static thread_local sd_resolve *default_resolve = NULL; sd_resolve *e = NULL; int r; if (!ret) return !!default_resolve; if (default_resolve) { *ret = sd_resolve_ref(default_resolve); return 0; } r = sd_resolve_new(&e); if (r < 0) return r; e->default_resolve_ptr = &default_resolve; e->tid = gettid(); default_resolve = e; *ret = e; return 1; } _public_ int sd_resolve_get_tid(sd_resolve *resolve, pid_t *tid) { assert_return(resolve, -EINVAL); assert_return(tid, -EINVAL); assert_return(!resolve_pid_changed(resolve), -ECHILD); if (resolve->tid != 0) { *tid = resolve->tid; return 0; } if (resolve->event) return sd_event_get_tid(resolve->event, tid); return -ENXIO; } static void resolve_free(sd_resolve *resolve) { PROTECT_ERRNO; unsigned i; assert(resolve); if (resolve->default_resolve_ptr) *(resolve->default_resolve_ptr) = NULL; resolve->dead = true; sd_resolve_detach_event(resolve); if (resolve->fds[REQUEST_SEND_FD] >= 0) { RHeader req = { .type = REQUEST_TERMINATE, .length = sizeof(req) }; /* Send one termination packet for each worker */ for (i = 0; i < resolve->n_valid_workers; i++) send(resolve->fds[REQUEST_SEND_FD], &req, req.length, MSG_NOSIGNAL); } /* Now terminate them and wait until they are gone. */ for (i = 0; i < resolve->n_valid_workers; i++) { for (;;) { if (pthread_join(resolve->workers[i], NULL) != EINTR) break; } } /* Close all communication channels */ for (i = 0; i < _FD_MAX; i++) safe_close(resolve->fds[i]); free(resolve); } _public_ sd_resolve* sd_resolve_ref(sd_resolve *resolve) { assert_return(resolve, NULL); assert(resolve->n_ref >= 1); resolve->n_ref++; return resolve; } _public_ sd_resolve* sd_resolve_unref(sd_resolve *resolve) { if (!resolve) return NULL; assert(resolve->n_ref >= 1); resolve->n_ref--; if (resolve->n_ref <= 0) resolve_free(resolve); return NULL; } _public_ int sd_resolve_get_fd(sd_resolve *resolve) { assert_return(resolve, -EINVAL); assert_return(!resolve_pid_changed(resolve), -ECHILD); return resolve->fds[RESPONSE_RECV_FD]; } _public_ int sd_resolve_get_events(sd_resolve *resolve) { assert_return(resolve, -EINVAL); assert_return(!resolve_pid_changed(resolve), -ECHILD); return resolve->n_queries > resolve->n_done ? POLLIN : 0; } _public_ int sd_resolve_get_timeout(sd_resolve *resolve, uint64_t *usec) { assert_return(resolve, -EINVAL); assert_return(usec, -EINVAL); assert_return(!resolve_pid_changed(resolve), -ECHILD); *usec = (uint64_t) -1; return 0; } static sd_resolve_query *lookup_query(sd_resolve *resolve, unsigned id) { sd_resolve_query *q; assert(resolve); q = resolve->queries[id % QUERIES_MAX]; if (q) if (q->id == id) return q; return NULL; } static int complete_query(sd_resolve *resolve, sd_resolve_query *q) { int r; assert(q); assert(!q->done); assert(q->resolve == resolve); q->done = true; resolve->n_done ++; resolve->current = q; switch (q->type) { case REQUEST_ADDRINFO: r = getaddrinfo_done(q); break; case REQUEST_NAMEINFO: r = getnameinfo_done(q); break; case REQUEST_RES_QUERY: case REQUEST_RES_SEARCH: r = res_query_done(q); break; default: assert_not_reached("Cannot complete unknown query type"); } resolve->current = NULL; return r; } static int unserialize_addrinfo(const void **p, size_t *length, struct addrinfo **ret_ai) { AddrInfoSerialization s; size_t l; struct addrinfo *ai; assert(p); assert(*p); assert(ret_ai); assert(length); if (*length < sizeof(AddrInfoSerialization)) return -EBADMSG; memcpy(&s, *p, sizeof(s)); l = sizeof(AddrInfoSerialization) + s.ai_addrlen + s.canonname_len; if (*length < l) return -EBADMSG; ai = new0(struct addrinfo, 1); if (!ai) return -ENOMEM; ai->ai_flags = s.ai_flags; ai->ai_family = s.ai_family; ai->ai_socktype = s.ai_socktype; ai->ai_protocol = s.ai_protocol; ai->ai_addrlen = s.ai_addrlen; if (s.ai_addrlen > 0) { ai->ai_addr = memdup((const uint8_t*) *p + sizeof(AddrInfoSerialization), s.ai_addrlen); if (!ai->ai_addr) { free(ai); return -ENOMEM; } } if (s.canonname_len > 0) { ai->ai_canonname = memdup((const uint8_t*) *p + sizeof(AddrInfoSerialization) + s.ai_addrlen, s.canonname_len); if (!ai->ai_canonname) { free(ai->ai_addr); free(ai); return -ENOMEM; } } *length -= l; *ret_ai = ai; *p = ((const uint8_t*) *p) + l; return 0; } static int handle_response(sd_resolve *resolve, const Packet *packet, size_t length) { const RHeader *resp; sd_resolve_query *q; int r; assert(resolve); resp = &packet->rheader; assert(resp); assert(length >= sizeof(RHeader)); assert(length == resp->length); if (resp->type == RESPONSE_DIED) { resolve->dead = true; return 0; } q = lookup_query(resolve, resp->id); if (!q) return 0; switch (resp->type) { case RESPONSE_ADDRINFO: { const AddrInfoResponse *ai_resp = &packet->addrinfo_response; const void *p; size_t l; struct addrinfo *prev = NULL; assert(length >= sizeof(AddrInfoResponse)); assert(q->type == REQUEST_ADDRINFO); q->ret = ai_resp->ret; q->_errno = ai_resp->_errno; q->_h_errno = ai_resp->_h_errno; l = length - sizeof(AddrInfoResponse); p = (const uint8_t*) resp + sizeof(AddrInfoResponse); while (l > 0 && p) { struct addrinfo *ai = NULL; r = unserialize_addrinfo(&p, &l, &ai); if (r < 0) { q->ret = EAI_SYSTEM; q->_errno = -r; q->_h_errno = 0; freeaddrinfo(q->addrinfo); q->addrinfo = NULL; break; } if (prev) prev->ai_next = ai; else q->addrinfo = ai; prev = ai; } return complete_query(resolve, q); } case RESPONSE_NAMEINFO: { const NameInfoResponse *ni_resp = &packet->nameinfo_response; assert(length >= sizeof(NameInfoResponse)); assert(q->type == REQUEST_NAMEINFO); q->ret = ni_resp->ret; q->_errno = ni_resp->_errno; q->_h_errno = ni_resp->_h_errno; if (ni_resp->hostlen > 0) { q->host = strndup((const char*) ni_resp + sizeof(NameInfoResponse), ni_resp->hostlen-1); if (!q->host) { q->ret = EAI_MEMORY; q->_errno = ENOMEM; q->_h_errno = 0; } } if (ni_resp->servlen > 0) { q->serv = strndup((const char*) ni_resp + sizeof(NameInfoResponse) + ni_resp->hostlen, ni_resp->servlen-1); if (!q->serv) { q->ret = EAI_MEMORY; q->_errno = ENOMEM; q->_h_errno = 0; } } return complete_query(resolve, q); } case RESPONSE_RES: { const ResResponse *res_resp = &packet->res_response; assert(length >= sizeof(ResResponse)); assert(q->type == REQUEST_RES_QUERY || q->type == REQUEST_RES_SEARCH); q->ret = res_resp->ret; q->_errno = res_resp->_errno; q->_h_errno = res_resp->_h_errno; if (res_resp->ret >= 0) { q->answer = memdup((const char *)resp + sizeof(ResResponse), res_resp->ret); if (!q->answer) { q->ret = -1; q->_errno = ENOMEM; q->_h_errno = 0; } } return complete_query(resolve, q); } default: return 0; } } _public_ int sd_resolve_process(sd_resolve *resolve) { RESOLVE_DONT_DESTROY(resolve); union { Packet packet; uint8_t space[BUFSIZE]; } buf; ssize_t l; int r; assert_return(resolve, -EINVAL); assert_return(!resolve_pid_changed(resolve), -ECHILD); /* We don't allow recursively invoking sd_resolve_process(). */ assert_return(!resolve->current, -EBUSY); l = recv(resolve->fds[RESPONSE_RECV_FD], &buf, sizeof(buf), 0); if (l < 0) { if (errno == EAGAIN) return 0; return -errno; } if (l == 0) return -ECONNREFUSED; r = handle_response(resolve, &buf.packet, (size_t) l); if (r < 0) return r; return 1; } _public_ int sd_resolve_wait(sd_resolve *resolve, uint64_t timeout_usec) { int r; assert_return(resolve, -EINVAL); assert_return(!resolve_pid_changed(resolve), -ECHILD); if (resolve->n_done >= resolve->n_queries) return 0; do { r = fd_wait_for_event(resolve->fds[RESPONSE_RECV_FD], POLLIN, timeout_usec); } while (r == -EINTR); if (r < 0) return r; return sd_resolve_process(resolve); } static int alloc_query(sd_resolve *resolve, sd_resolve_query **_q) { sd_resolve_query *q; int r; assert(resolve); assert(_q); if (resolve->n_queries >= QUERIES_MAX) return -ENOBUFS; r = start_threads(resolve, 1); if (r < 0) return r; while (resolve->queries[resolve->current_index]) { resolve->current_index++; resolve->current_id++; resolve->current_index %= QUERIES_MAX; } q = resolve->queries[resolve->current_index] = new0(sd_resolve_query, 1); if (!q) return -ENOMEM; q->n_ref = 1; q->resolve = sd_resolve_ref(resolve); q->id = resolve->current_id; resolve->n_queries++; *_q = q; return 0; } _public_ int sd_resolve_getaddrinfo( sd_resolve *resolve, sd_resolve_query **_q, const char *node, const char *service, const struct addrinfo *hints, sd_resolve_getaddrinfo_handler_t callback, void *userdata) { AddrInfoRequest req = {}; struct msghdr mh = {}; struct iovec iov[3]; sd_resolve_query *q; int r; assert_return(resolve, -EINVAL); assert_return(_q, -EINVAL); assert_return(node || service, -EINVAL); assert_return(callback, -EINVAL); assert_return(!resolve_pid_changed(resolve), -ECHILD); r = alloc_query(resolve, &q); if (r < 0) return r; q->type = REQUEST_ADDRINFO; q->getaddrinfo_handler = callback; q->userdata = userdata; req.node_len = node ? strlen(node)+1 : 0; req.service_len = service ? strlen(service)+1 : 0; req.header.id = q->id; req.header.type = REQUEST_ADDRINFO; req.header.length = sizeof(AddrInfoRequest) + req.node_len + req.service_len; if (hints) { req.hints_valid = true; req.ai_flags = hints->ai_flags; req.ai_family = hints->ai_family; req.ai_socktype = hints->ai_socktype; req.ai_protocol = hints->ai_protocol; } iov[mh.msg_iovlen++] = (struct iovec) { .iov_base = &req, .iov_len = sizeof(AddrInfoRequest) }; if (node) iov[mh.msg_iovlen++] = (struct iovec) { .iov_base = (void*) node, .iov_len = req.node_len }; if (service) iov[mh.msg_iovlen++] = (struct iovec) { .iov_base = (void*) service, .iov_len = req.service_len }; mh.msg_iov = iov; if (sendmsg(resolve->fds[REQUEST_SEND_FD], &mh, MSG_NOSIGNAL) < 0) { sd_resolve_query_unref(q); return -errno; } *_q = q; return 0; } static int getaddrinfo_done(sd_resolve_query* q) { assert(q); assert(q->done); assert(q->getaddrinfo_handler); errno = q->_errno; h_errno = q->_h_errno; return q->getaddrinfo_handler(q, q->ret, q->addrinfo, q->userdata); } _public_ int sd_resolve_getnameinfo( sd_resolve *resolve, sd_resolve_query**_q, const struct sockaddr *sa, socklen_t salen, int flags, uint64_t get, sd_resolve_getnameinfo_handler_t callback, void *userdata) { NameInfoRequest req = {}; struct msghdr mh = {}; struct iovec iov[2]; sd_resolve_query *q; int r; assert_return(resolve, -EINVAL); assert_return(_q, -EINVAL); assert_return(sa, -EINVAL); assert_return(salen >= sizeof(struct sockaddr), -EINVAL); assert_return(salen <= sizeof(union sockaddr_union), -EINVAL); assert_return((get & ~SD_RESOLVE_GET_BOTH) == 0, -EINVAL); assert_return(callback, -EINVAL); assert_return(!resolve_pid_changed(resolve), -ECHILD); r = alloc_query(resolve, &q); if (r < 0) return r; q->type = REQUEST_NAMEINFO; q->getnameinfo_handler = callback; q->userdata = userdata; req.header.id = q->id; req.header.type = REQUEST_NAMEINFO; req.header.length = sizeof(NameInfoRequest) + salen; req.flags = flags; req.sockaddr_len = salen; req.gethost = !!(get & SD_RESOLVE_GET_HOST); req.getserv = !!(get & SD_RESOLVE_GET_SERVICE); iov[0] = (struct iovec) { .iov_base = &req, .iov_len = sizeof(NameInfoRequest) }; iov[1] = (struct iovec) { .iov_base = (void*) sa, .iov_len = salen }; mh.msg_iov = iov; mh.msg_iovlen = 2; if (sendmsg(resolve->fds[REQUEST_SEND_FD], &mh, MSG_NOSIGNAL) < 0) { sd_resolve_query_unref(q); return -errno; } *_q = q; return 0; } static int getnameinfo_done(sd_resolve_query *q) { assert(q); assert(q->done); assert(q->getnameinfo_handler); errno = q->_errno; h_errno= q->_h_errno; return q->getnameinfo_handler(q, q->ret, q->host, q->serv, q->userdata); } static int resolve_res( sd_resolve *resolve, sd_resolve_query **_q, QueryType qtype, const char *dname, int class, int type, sd_resolve_res_handler_t callback, void *userdata) { struct msghdr mh = {}; struct iovec iov[2]; ResRequest req = {}; sd_resolve_query *q; int r; assert_return(resolve, -EINVAL); assert_return(_q, -EINVAL); assert_return(dname, -EINVAL); assert_return(callback, -EINVAL); assert_return(!resolve_pid_changed(resolve), -ECHILD); r = alloc_query(resolve, &q); if (r < 0) return r; q->type = qtype; q->res_handler = callback; q->userdata = userdata; req.dname_len = strlen(dname) + 1; req.class = class; req.type = type; req.header.id = q->id; req.header.type = qtype; req.header.length = sizeof(ResRequest) + req.dname_len; iov[0] = (struct iovec) { .iov_base = &req, .iov_len = sizeof(ResRequest) }; iov[1] = (struct iovec) { .iov_base = (void*) dname, .iov_len = req.dname_len }; mh.msg_iov = iov; mh.msg_iovlen = 2; if (sendmsg(resolve->fds[REQUEST_SEND_FD], &mh, MSG_NOSIGNAL) < 0) { sd_resolve_query_unref(q); return -errno; } *_q = q; return 0; } _public_ int sd_resolve_res_query(sd_resolve *resolve, sd_resolve_query** q, const char *dname, int class, int type, sd_resolve_res_handler_t callback, void *userdata) { return resolve_res(resolve, q, REQUEST_RES_QUERY, dname, class, type, callback, userdata); } _public_ int sd_resolve_res_search(sd_resolve *resolve, sd_resolve_query** q, const char *dname, int class, int type, sd_resolve_res_handler_t callback, void *userdata) { return resolve_res(resolve, q, REQUEST_RES_SEARCH, dname, class, type, callback, userdata); } static int res_query_done(sd_resolve_query* q) { assert(q); assert(q->done); assert(q->res_handler); errno = q->_errno; h_errno = q->_h_errno; return q->res_handler(q, q->ret, q->answer, q->userdata); } _public_ sd_resolve_query* sd_resolve_query_ref(sd_resolve_query *q) { assert_return(q, NULL); assert(q->n_ref >= 1); q->n_ref++; return q; } static void resolve_freeaddrinfo(struct addrinfo *ai) { while (ai) { struct addrinfo *next = ai->ai_next; free(ai->ai_addr); free(ai->ai_canonname); free(ai); ai = next; } } static void resolve_query_free(sd_resolve_query *q) { unsigned i; assert(q); assert(q->resolve); assert(q->resolve->n_queries > 0); if (q->done) { assert(q->resolve->n_done > 0); q->resolve->n_done--; } i = q->id % QUERIES_MAX; assert(q->resolve->queries[i] == q); q->resolve->queries[i] = NULL; q->resolve->n_queries--; sd_resolve_unref(q->resolve); resolve_freeaddrinfo(q->addrinfo); free(q->host); free(q->serv); free(q->answer); free(q); } _public_ sd_resolve_query* sd_resolve_query_unref(sd_resolve_query* q) { if (!q) return NULL; assert(q->n_ref >= 1); q->n_ref--; if (q->n_ref <= 0) resolve_query_free(q); return NULL; } _public_ int sd_resolve_query_is_done(sd_resolve_query *q) { assert_return(q, -EINVAL); assert_return(!resolve_pid_changed(q->resolve), -ECHILD); return q->done; } _public_ void* sd_resolve_query_set_userdata(sd_resolve_query *q, void *userdata) { void *ret; assert_return(q, NULL); assert_return(!resolve_pid_changed(q->resolve), NULL); ret = q->userdata; q->userdata = userdata; return ret; } _public_ void* sd_resolve_query_get_userdata(sd_resolve_query *q) { assert_return(q, NULL); assert_return(!resolve_pid_changed(q->resolve), NULL); return q->userdata; } _public_ sd_resolve *sd_resolve_query_get_resolve(sd_resolve_query *q) { assert_return(q, NULL); assert_return(!resolve_pid_changed(q->resolve), NULL); return q->resolve; } static int io_callback(sd_event_source *s, int fd, uint32_t revents, void *userdata) { sd_resolve *resolve = userdata; int r; assert(resolve); r = sd_resolve_process(resolve); if (r < 0) return r; return 1; } _public_ int sd_resolve_attach_event(sd_resolve *resolve, sd_event *event, int priority) { int r; assert_return(resolve, -EINVAL); assert_return(!resolve->event, -EBUSY); assert(!resolve->event_source); if (event) resolve->event = sd_event_ref(event); else { r = sd_event_default(&resolve->event); if (r < 0) return r; } r = sd_event_add_io(resolve->event, &resolve->event_source, resolve->fds[RESPONSE_RECV_FD], POLLIN, io_callback, resolve); if (r < 0) goto fail; r = sd_event_source_set_priority(resolve->event_source, priority); if (r < 0) goto fail; return 0; fail: sd_resolve_detach_event(resolve); return r; } _public_ int sd_resolve_detach_event(sd_resolve *resolve) { assert_return(resolve, -EINVAL); if (!resolve->event) return 0; if (resolve->event_source) { sd_event_source_set_enabled(resolve->event_source, SD_EVENT_OFF); resolve->event_source = sd_event_source_unref(resolve->event_source); } resolve->event = sd_event_unref(resolve->event); return 1; } _public_ sd_event *sd_resolve_get_event(sd_resolve *resolve) { assert_return(resolve, NULL); return resolve->event; }