diff options
Diffstat (limited to 'src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.c')
| -rw-r--r-- | src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.c | 366 |
1 files changed, 254 insertions, 112 deletions
diff --git a/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.c b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.c index e0cfd8b629..244b260dfa 100644 --- a/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.c +++ b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.c @@ -1,33 +1,18 @@ /* * - * Copyright 2016, Google Inc. - * All rights reserved. + * Copyright 2016 gRPC authors. * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions are - * met: + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at * - * * Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * * Redistributions in binary form must reproduce the above - * copyright notice, this list of conditions and the following disclaimer - * in the documentation and/or other materials provided with the - * distribution. - * * Neither the name of Google Inc. nor the names of its - * contributors may be used to endorse or promote products derived from - * this software without specific prior written permission. + * http://www.apache.org/licenses/LICENSE-2.0 * - * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS - * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT - * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR - * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT - * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, - * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT - * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, - * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY - * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT - * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE - * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. * */ @@ -48,6 +33,7 @@ #include <grpc/support/string_util.h> #include <grpc/support/time.h> #include <grpc/support/useful.h> +#include <nameser.h> #include "src/core/ext/filters/client_channel/parse_address.h" #include "src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.h" @@ -60,20 +46,14 @@ static gpr_once g_basic_init = GPR_ONCE_INIT; static gpr_mu g_init_mu; -typedef struct grpc_ares_request { +struct grpc_ares_request { /** indicates the DNS server to use, if specified */ struct ares_addr_port_node dns_server_addr; /** following members are set in grpc_resolve_address_ares_impl */ - /** host to resolve, parsed from the name to resolve */ - char *host; - /** port to fill in sockaddr_in, parsed from the name to resolve */ - char *port; - /** default port to use */ - char *default_port; /** closure to call when the request completes */ grpc_closure *on_done; /** the pointer to receive the resolved addresses */ - grpc_resolved_addresses **addrs_out; + grpc_lb_addresses **lb_addrs_out; /** the evernt driver used by this request */ grpc_ares_ev_driver *ev_driver; /** number of ongoing queries */ @@ -85,7 +65,19 @@ typedef struct grpc_ares_request { bool success; /** the errors explaining the request failure, set in on_done_cb */ grpc_error *error; -} grpc_ares_request; +}; + +typedef struct grpc_ares_hostbyname_request { + /** following members are set in create_hostbyname_request */ + /** the top-level request instance */ + grpc_ares_request *parent_request; + /** host to resolve, parsed from the name to resolve */ + char *host; + /** port to fill in sockaddr_in, parsed from the name to resolve */ + uint16_t port; + /** is it a grpclb address */ + bool is_balancer; +} grpc_ares_hostbyname_request; static void do_basic_init(void) { gpr_mu_init(&g_init_mu); } @@ -98,6 +90,10 @@ static uint16_t strhtons(const char *port) { return htons((unsigned short)atoi(port)); } +static void grpc_ares_request_ref(grpc_ares_request *r) { + gpr_ref(&r->pending_queries); +} + static void grpc_ares_request_unref(grpc_exec_ctx *exec_ctx, grpc_ares_request *r) { /* If there are no pending queries, invoke on_done callback and destroy the @@ -111,74 +107,102 @@ static void grpc_ares_request_unref(grpc_exec_ctx *exec_ctx, acquire locks in on_done. ares_dns_resolver is using combiner to protect resources needed by on_done. */ grpc_exec_ctx new_exec_ctx = GRPC_EXEC_CTX_INIT; - grpc_closure_sched(&new_exec_ctx, r->on_done, r->error); + GRPC_CLOSURE_SCHED(&new_exec_ctx, r->on_done, r->error); grpc_exec_ctx_finish(&new_exec_ctx); } else { - grpc_closure_sched(exec_ctx, r->on_done, r->error); + GRPC_CLOSURE_SCHED(exec_ctx, r->on_done, r->error); } gpr_mu_destroy(&r->mu); grpc_ares_ev_driver_destroy(r->ev_driver); - gpr_free(r->host); - gpr_free(r->port); - gpr_free(r->default_port); gpr_free(r); } } -static void on_done_cb(void *arg, int status, int timeouts, - struct hostent *hostent) { - grpc_ares_request *r = (grpc_ares_request *)arg; +static grpc_ares_hostbyname_request *create_hostbyname_request( + grpc_ares_request *parent_request, char *host, uint16_t port, + bool is_balancer) { + grpc_ares_hostbyname_request *hr = + gpr_zalloc(sizeof(grpc_ares_hostbyname_request)); + hr->parent_request = parent_request; + hr->host = gpr_strdup(host); + hr->port = port; + hr->is_balancer = is_balancer; + grpc_ares_request_ref(parent_request); + return hr; +} + +static void destroy_hostbyname_request(grpc_exec_ctx *exec_ctx, + grpc_ares_hostbyname_request *hr) { + grpc_ares_request_unref(exec_ctx, hr->parent_request); + gpr_free(hr->host); + gpr_free(hr); +} + +static void on_hostbyname_done_cb(void *arg, int status, int timeouts, + struct hostent *hostent) { + grpc_ares_hostbyname_request *hr = (grpc_ares_hostbyname_request *)arg; + grpc_ares_request *r = hr->parent_request; gpr_mu_lock(&r->mu); if (status == ARES_SUCCESS) { GRPC_ERROR_UNREF(r->error); r->error = GRPC_ERROR_NONE; r->success = true; - grpc_resolved_addresses **addresses = r->addrs_out; - if (*addresses == NULL) { - *addresses = gpr_malloc(sizeof(grpc_resolved_addresses)); - (*addresses)->naddrs = 0; - (*addresses)->addrs = NULL; + grpc_lb_addresses **lb_addresses = r->lb_addrs_out; + if (*lb_addresses == NULL) { + *lb_addresses = grpc_lb_addresses_create(0, NULL); } - size_t prev_naddr = (*addresses)->naddrs; + size_t prev_naddr = (*lb_addresses)->num_addresses; size_t i; for (i = 0; hostent->h_addr_list[i] != NULL; i++) { } - (*addresses)->naddrs += i; - (*addresses)->addrs = - gpr_realloc((*addresses)->addrs, - sizeof(grpc_resolved_address) * (*addresses)->naddrs); - for (i = prev_naddr; i < (*addresses)->naddrs; i++) { - memset(&(*addresses)->addrs[i], 0, sizeof(grpc_resolved_address)); - if (hostent->h_addrtype == AF_INET6) { - (*addresses)->addrs[i].len = sizeof(struct sockaddr_in6); - struct sockaddr_in6 *addr = - (struct sockaddr_in6 *)&(*addresses)->addrs[i].addr; - addr->sin6_family = (sa_family_t)hostent->h_addrtype; - addr->sin6_port = strhtons(r->port); - - char output[INET6_ADDRSTRLEN]; - memcpy(&addr->sin6_addr, hostent->h_addr_list[i - prev_naddr], - sizeof(struct in6_addr)); - ares_inet_ntop(AF_INET6, &addr->sin6_addr, output, INET6_ADDRSTRLEN); - gpr_log(GPR_DEBUG, - "c-ares resolver gets a AF_INET6 result: \n" - " addr: %s\n port: %s\n sin6_scope_id: %d\n", - output, r->port, addr->sin6_scope_id); - } else { - (*addresses)->addrs[i].len = sizeof(struct sockaddr_in); - struct sockaddr_in *addr = - (struct sockaddr_in *)&(*addresses)->addrs[i].addr; - memcpy(&addr->sin_addr, hostent->h_addr_list[i - prev_naddr], - sizeof(struct in_addr)); - addr->sin_family = (sa_family_t)hostent->h_addrtype; - addr->sin_port = strhtons(r->port); - - char output[INET_ADDRSTRLEN]; - ares_inet_ntop(AF_INET, &addr->sin_addr, output, INET_ADDRSTRLEN); - gpr_log(GPR_DEBUG, - "c-ares resolver gets a AF_INET result: \n" - " addr: %s\n port: %s\n", - output, r->port); + (*lb_addresses)->num_addresses += i; + (*lb_addresses)->addresses = + gpr_realloc((*lb_addresses)->addresses, + sizeof(grpc_lb_address) * (*lb_addresses)->num_addresses); + for (i = prev_naddr; i < (*lb_addresses)->num_addresses; i++) { + switch (hostent->h_addrtype) { + case AF_INET6: { + size_t addr_len = sizeof(struct sockaddr_in6); + struct sockaddr_in6 addr; + memset(&addr, 0, addr_len); + memcpy(&addr.sin6_addr, hostent->h_addr_list[i - prev_naddr], + sizeof(struct in6_addr)); + addr.sin6_family = (sa_family_t)hostent->h_addrtype; + addr.sin6_port = hr->port; + grpc_lb_addresses_set_address( + *lb_addresses, i, &addr, addr_len, + hr->is_balancer /* is_balancer */, + hr->is_balancer ? strdup(hr->host) : NULL /* balancer_name */, + NULL /* user_data */); + char output[INET6_ADDRSTRLEN]; + ares_inet_ntop(AF_INET6, &addr.sin6_addr, output, INET6_ADDRSTRLEN); + gpr_log(GPR_DEBUG, + "c-ares resolver gets a AF_INET6 result: \n" + " addr: %s\n port: %d\n sin6_scope_id: %d\n", + output, ntohs(hr->port), addr.sin6_scope_id); + break; + } + case AF_INET: { + size_t addr_len = sizeof(struct sockaddr_in); + struct sockaddr_in addr; + memset(&addr, 0, addr_len); + memcpy(&addr.sin_addr, hostent->h_addr_list[i - prev_naddr], + sizeof(struct in_addr)); + addr.sin_family = (sa_family_t)hostent->h_addrtype; + addr.sin_port = hr->port; + grpc_lb_addresses_set_address( + *lb_addresses, i, &addr, addr_len, + hr->is_balancer /* is_balancer */, + hr->is_balancer ? strdup(hr->host) : NULL /* balancer_name */, + NULL /* user_data */); + char output[INET_ADDRSTRLEN]; + ares_inet_ntop(AF_INET, &addr.sin_addr, output, INET_ADDRSTRLEN); + gpr_log(GPR_DEBUG, + "c-ares resolver gets a AF_INET result: \n" + " addr: %s\n port: %d\n", + output, ntohs(hr->port)); + break; + } } } } else if (!r->success) { @@ -194,14 +218,58 @@ static void on_done_cb(void *arg, int status, int timeouts, } } gpr_mu_unlock(&r->mu); - grpc_ares_request_unref(NULL, r); + destroy_hostbyname_request(NULL, hr); +} + +static void on_srv_query_done_cb(void *arg, int status, int timeouts, + unsigned char *abuf, int alen) { + grpc_ares_request *r = (grpc_ares_request *)arg; + grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT; + gpr_log(GPR_DEBUG, "on_query_srv_done_cb"); + if (status == ARES_SUCCESS) { + gpr_log(GPR_DEBUG, "on_query_srv_done_cb ARES_SUCCESS"); + struct ares_srv_reply *reply; + const int parse_status = ares_parse_srv_reply(abuf, alen, &reply); + if (parse_status == ARES_SUCCESS) { + ares_channel *channel = grpc_ares_ev_driver_get_channel(r->ev_driver); + for (struct ares_srv_reply *srv_it = reply; srv_it != NULL; + srv_it = srv_it->next) { + if (grpc_ipv6_loopback_available()) { + grpc_ares_hostbyname_request *hr = create_hostbyname_request( + r, srv_it->host, srv_it->port, true /* is_balancer */); + ares_gethostbyname(*channel, hr->host, AF_INET6, + on_hostbyname_done_cb, hr); + } + grpc_ares_hostbyname_request *hr = create_hostbyname_request( + r, srv_it->host, srv_it->port, true /* is_balancer */); + ares_gethostbyname(*channel, hr->host, AF_INET, on_hostbyname_done_cb, + hr); + grpc_ares_ev_driver_start(&exec_ctx, r->ev_driver); + } + } + if (reply != NULL) { + ares_free_data(reply); + } + } else if (!r->success) { + char *error_msg; + gpr_asprintf(&error_msg, "C-ares status is not ARES_SUCCESS: %s", + ares_strerror(status)); + grpc_error *error = GRPC_ERROR_CREATE_FROM_COPIED_STRING(error_msg); + gpr_free(error_msg); + if (r->error == GRPC_ERROR_NONE) { + r->error = error; + } else { + r->error = grpc_error_add_child(error, r->error); + } + } + grpc_ares_request_unref(&exec_ctx, r); + grpc_exec_ctx_finish(&exec_ctx); } -void grpc_dns_lookup_ares(grpc_exec_ctx *exec_ctx, const char *dns_server, - const char *name, const char *default_port, - grpc_pollset_set *interested_parties, - grpc_closure *on_done, - grpc_resolved_addresses **addrs) { +static grpc_ares_request *grpc_dns_lookup_ares_impl( + grpc_exec_ctx *exec_ctx, const char *dns_server, const char *name, + const char *default_port, grpc_pollset_set *interested_parties, + grpc_closure *on_done, grpc_lb_addresses **addrs, bool check_grpclb) { grpc_error *error = GRPC_ERROR_NONE; /* TODO(zyc): Enable tracing after #9603 is checked in */ /* if (grpc_dns_trace) { @@ -236,10 +304,7 @@ void grpc_dns_lookup_ares(grpc_exec_ctx *exec_ctx, const char *dns_server, gpr_mu_init(&r->mu); r->ev_driver = ev_driver; r->on_done = on_done; - r->addrs_out = addrs; - r->default_port = gpr_strdup(default_port); - r->port = port; - r->host = host; + r->lb_addrs_out = addrs; r->success = false; r->error = GRPC_ERROR_NONE; ares_channel *channel = grpc_ares_ev_driver_get_channel(r->ev_driver); @@ -263,6 +328,7 @@ void grpc_dns_lookup_ares(grpc_exec_ctx *exec_ctx, const char *dns_server, error = grpc_error_set_str( GRPC_ERROR_CREATE_FROM_STATIC_STRING("cannot parse authority"), GRPC_ERROR_STR_TARGET_ADDRESS, grpc_slice_from_copied_string(name)); + gpr_free(r); goto error_cleanup; } int status = ares_set_servers_ports(*channel, &r->dns_server_addr); @@ -272,41 +338,55 @@ void grpc_dns_lookup_ares(grpc_exec_ctx *exec_ctx, const char *dns_server, ares_strerror(status)); error = GRPC_ERROR_CREATE_FROM_COPIED_STRING(error_msg); gpr_free(error_msg); + gpr_free(r); goto error_cleanup; } } // An extra reference is put here to avoid destroying the request in // on_done_cb before calling grpc_ares_ev_driver_start. - gpr_ref_init(&r->pending_queries, 2); + gpr_ref_init(&r->pending_queries, 1); if (grpc_ipv6_loopback_available()) { - gpr_ref(&r->pending_queries); - ares_gethostbyname(*channel, r->host, AF_INET6, on_done_cb, r); + grpc_ares_hostbyname_request *hr = create_hostbyname_request( + r, host, strhtons(port), false /* is_balancer */); + ares_gethostbyname(*channel, hr->host, AF_INET6, on_hostbyname_done_cb, hr); + } + grpc_ares_hostbyname_request *hr = create_hostbyname_request( + r, host, strhtons(port), false /* is_balancer */); + ares_gethostbyname(*channel, hr->host, AF_INET, on_hostbyname_done_cb, hr); + if (check_grpclb) { + /* Query the SRV record */ + grpc_ares_request_ref(r); + char *service_name; + gpr_asprintf(&service_name, "_grpclb._tcp.%s", host); + ares_query(*channel, service_name, ns_c_in, ns_t_srv, on_srv_query_done_cb, + r); + gpr_free(service_name); } - ares_gethostbyname(*channel, r->host, AF_INET, on_done_cb, r); /* TODO(zyc): Handle CNAME records here. */ grpc_ares_ev_driver_start(exec_ctx, r->ev_driver); grpc_ares_request_unref(exec_ctx, r); - return; + gpr_free(host); + gpr_free(port); + return r; error_cleanup: - grpc_closure_sched(exec_ctx, on_done, error); + GRPC_CLOSURE_SCHED(exec_ctx, on_done, error); gpr_free(host); gpr_free(port); + return NULL; } -void grpc_resolve_address_ares_impl(grpc_exec_ctx *exec_ctx, const char *name, - const char *default_port, - grpc_pollset_set *interested_parties, - grpc_closure *on_done, - grpc_resolved_addresses **addrs) { - grpc_dns_lookup_ares(exec_ctx, NULL /* dns_server */, name, default_port, - interested_parties, on_done, addrs); -} +grpc_ares_request *(*grpc_dns_lookup_ares)( + grpc_exec_ctx *exec_ctx, const char *dns_server, const char *name, + const char *default_port, grpc_pollset_set *interested_parties, + grpc_closure *on_done, grpc_lb_addresses **addrs, + bool check_grpclb) = grpc_dns_lookup_ares_impl; -void (*grpc_resolve_address_ares)( - grpc_exec_ctx *exec_ctx, const char *name, const char *default_port, - grpc_pollset_set *interested_parties, grpc_closure *on_done, - grpc_resolved_addresses **addrs) = grpc_resolve_address_ares_impl; +void grpc_cancel_ares_request(grpc_exec_ctx *exec_ctx, grpc_ares_request *r) { + if (grpc_dns_lookup_ares == grpc_dns_lookup_ares_impl) { + grpc_ares_ev_driver_shutdown(exec_ctx, r->ev_driver); + } +} grpc_error *grpc_ares_init(void) { gpr_once_init(&g_basic_init, do_basic_init); @@ -331,4 +411,66 @@ void grpc_ares_cleanup(void) { gpr_mu_unlock(&g_init_mu); } +/* + * grpc_resolve_address_ares related structs and functions + */ + +typedef struct grpc_resolve_address_ares_request { + /** the pointer to receive the resolved addresses */ + grpc_resolved_addresses **addrs_out; + /** currently resolving lb addresses */ + grpc_lb_addresses *lb_addrs; + /** closure to call when the resolve_address_ares request completes */ + grpc_closure *on_resolve_address_done; + /** a closure wrapping on_dns_lookup_done_cb, which should be invoked when the + grpc_dns_lookup_ares operation is done. */ + grpc_closure on_dns_lookup_done; +} grpc_resolve_address_ares_request; + +static void on_dns_lookup_done_cb(grpc_exec_ctx *exec_ctx, void *arg, + grpc_error *error) { + grpc_resolve_address_ares_request *r = + (grpc_resolve_address_ares_request *)arg; + grpc_resolved_addresses **resolved_addresses = r->addrs_out; + if (r->lb_addrs == NULL || r->lb_addrs->num_addresses == 0) { + *resolved_addresses = NULL; + } else { + *resolved_addresses = gpr_zalloc(sizeof(grpc_resolved_addresses)); + (*resolved_addresses)->naddrs = r->lb_addrs->num_addresses; + (*resolved_addresses)->addrs = gpr_zalloc(sizeof(grpc_resolved_address) * + (*resolved_addresses)->naddrs); + for (size_t i = 0; i < (*resolved_addresses)->naddrs; i++) { + GPR_ASSERT(!r->lb_addrs->addresses[i].is_balancer); + memcpy(&(*resolved_addresses)->addrs[i], + &r->lb_addrs->addresses[i].address, sizeof(grpc_resolved_address)); + } + } + GRPC_CLOSURE_SCHED(exec_ctx, r->on_resolve_address_done, + GRPC_ERROR_REF(error)); + grpc_lb_addresses_destroy(exec_ctx, r->lb_addrs); + gpr_free(r); +} + +static void grpc_resolve_address_ares_impl(grpc_exec_ctx *exec_ctx, + const char *name, + const char *default_port, + grpc_pollset_set *interested_parties, + grpc_closure *on_done, + grpc_resolved_addresses **addrs) { + grpc_resolve_address_ares_request *r = + gpr_zalloc(sizeof(grpc_resolve_address_ares_request)); + r->addrs_out = addrs; + r->on_resolve_address_done = on_done; + GRPC_CLOSURE_INIT(&r->on_dns_lookup_done, on_dns_lookup_done_cb, r, + grpc_schedule_on_exec_ctx); + grpc_dns_lookup_ares(exec_ctx, NULL /* dns_server */, name, default_port, + interested_parties, &r->on_dns_lookup_done, &r->lb_addrs, + false /* check_grpclb */); +} + +void (*grpc_resolve_address_ares)( + grpc_exec_ctx *exec_ctx, const char *name, const char *default_port, + grpc_pollset_set *interested_parties, grpc_closure *on_done, + grpc_resolved_addresses **addrs) = grpc_resolve_address_ares_impl; + #endif /* GRPC_ARES == 1 && !defined(GRPC_UV) */ |