mirror of https://github.com/c-ares/c-ares.git
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
2620 lines
74 KiB
2620 lines
74 KiB
|
|
/* Copyright 1998 by the Massachusetts Institute of Technology. |
|
* Copyright (C) 2007-2013 by Daniel Stenberg |
|
* |
|
* Permission to use, copy, modify, and distribute this |
|
* software and its documentation for any purpose and without |
|
* fee is hereby granted, provided that the above copyright |
|
* notice appear in all copies and that both that copyright |
|
* notice and this permission notice appear in supporting |
|
* documentation, and that the name of M.I.T. not be used in |
|
* advertising or publicity pertaining to distribution of the |
|
* software without specific, written prior permission. |
|
* M.I.T. makes no representations about the suitability of |
|
* this software for any purpose. It is provided "as is" |
|
* without express or implied warranty. |
|
*/ |
|
|
|
#include "ares_setup.h" |
|
|
|
#ifdef HAVE_SYS_PARAM_H |
|
#include <sys/param.h> |
|
#endif |
|
|
|
#ifdef HAVE_NETINET_IN_H |
|
#include <netinet/in.h> |
|
#endif |
|
|
|
#ifdef HAVE_NETDB_H |
|
#include <netdb.h> |
|
#endif |
|
|
|
#ifdef HAVE_ARPA_INET_H |
|
#include <arpa/inet.h> |
|
#endif |
|
|
|
#ifdef HAVE_ARPA_NAMESER_H |
|
# include <arpa/nameser.h> |
|
#else |
|
# include "nameser.h" |
|
#endif |
|
#ifdef HAVE_ARPA_NAMESER_COMPAT_H |
|
# include <arpa/nameser_compat.h> |
|
#endif |
|
|
|
#if defined(ANDROID) || defined(__ANDROID__) |
|
#include <sys/system_properties.h> |
|
#include "ares_android.h" |
|
/* From the Bionic sources */ |
|
#define DNS_PROP_NAME_PREFIX "net.dns" |
|
#define MAX_DNS_PROPERTIES 8 |
|
#endif |
|
|
|
#if defined(CARES_USE_LIBRESOLV) |
|
#include <resolv.h> |
|
#endif |
|
|
|
#include "ares.h" |
|
#include "ares_inet_net_pton.h" |
|
#include "ares_library_init.h" |
|
#include "ares_nowarn.h" |
|
#include "ares_platform.h" |
|
#include "ares_private.h" |
|
|
|
#ifdef WATT32 |
|
#undef WIN32 /* Redefined in MingW/MSVC headers */ |
|
#endif |
|
|
|
static int init_by_options(ares_channel channel, |
|
const struct ares_options *options, |
|
int optmask); |
|
static int init_by_environment(ares_channel channel); |
|
static int init_by_resolv_conf(ares_channel channel); |
|
static int init_by_defaults(ares_channel channel); |
|
|
|
#ifndef WATT32 |
|
static int config_nameserver(struct server_state **servers, int *nservers, |
|
char *str); |
|
#endif |
|
static int set_search(ares_channel channel, const char *str); |
|
static int set_options(ares_channel channel, const char *str); |
|
static const char *try_option(const char *p, const char *q, const char *opt); |
|
static int init_id_key(rc4_key* key,int key_data_len); |
|
|
|
static int config_sortlist(struct apattern **sortlist, int *nsort, |
|
const char *str); |
|
static int sortlist_alloc(struct apattern **sortlist, int *nsort, |
|
struct apattern *pat); |
|
static int ip_addr(const char *s, ares_ssize_t len, struct in_addr *addr); |
|
static void natural_mask(struct apattern *pat); |
|
#if !defined(WIN32) && !defined(WATT32) && \ |
|
!defined(ANDROID) && !defined(__ANDROID__) && !defined(CARES_USE_LIBRESOLV) |
|
static int config_domain(ares_channel channel, char *str); |
|
static int config_lookup(ares_channel channel, const char *str, |
|
const char *bindch, const char *altbindch, |
|
const char *filech); |
|
static char *try_config(char *s, const char *opt, char scc); |
|
#endif |
|
|
|
#define ARES_CONFIG_CHECK(x) (x->lookups && x->nsort > -1 && \ |
|
x->nservers > -1 && \ |
|
x->ndomains > -1 && \ |
|
x->ndots > -1 && x->timeout > -1 && \ |
|
x->tries > -1) |
|
|
|
int ares_init(ares_channel *channelptr) |
|
{ |
|
return ares_init_options(channelptr, NULL, 0); |
|
} |
|
|
|
int ares_init_options(ares_channel *channelptr, struct ares_options *options, |
|
int optmask) |
|
{ |
|
ares_channel channel; |
|
int i; |
|
int status = ARES_SUCCESS; |
|
struct timeval now; |
|
|
|
#ifdef CURLDEBUG |
|
const char *env = getenv("CARES_MEMDEBUG"); |
|
|
|
if (env) |
|
curl_memdebug(env); |
|
env = getenv("CARES_MEMLIMIT"); |
|
if (env) { |
|
char *endptr; |
|
long num = strtol(env, &endptr, 10); |
|
if((endptr != env) && (endptr == env + strlen(env)) && (num > 0)) |
|
curl_memlimit(num); |
|
} |
|
#endif |
|
|
|
if (ares_library_initialized() != ARES_SUCCESS) |
|
return ARES_ENOTINITIALIZED; /* LCOV_EXCL_LINE: n/a on non-WinSock */ |
|
|
|
channel = ares_malloc(sizeof(struct ares_channeldata)); |
|
if (!channel) { |
|
*channelptr = NULL; |
|
return ARES_ENOMEM; |
|
} |
|
|
|
now = ares__tvnow(); |
|
|
|
/* Set everything to distinguished values so we know they haven't |
|
* been set yet. |
|
*/ |
|
channel->flags = -1; |
|
channel->timeout = -1; |
|
channel->tries = -1; |
|
channel->ndots = -1; |
|
channel->rotate = -1; |
|
channel->udp_port = -1; |
|
channel->tcp_port = -1; |
|
channel->ednspsz = -1; |
|
channel->socket_send_buffer_size = -1; |
|
channel->socket_receive_buffer_size = -1; |
|
channel->nservers = -1; |
|
channel->ndomains = -1; |
|
channel->nsort = -1; |
|
channel->tcp_connection_generation = 0; |
|
channel->lookups = NULL; |
|
channel->domains = NULL; |
|
channel->sortlist = NULL; |
|
channel->servers = NULL; |
|
channel->sock_state_cb = NULL; |
|
channel->sock_state_cb_data = NULL; |
|
channel->sock_create_cb = NULL; |
|
channel->sock_create_cb_data = NULL; |
|
channel->sock_config_cb = NULL; |
|
channel->sock_config_cb_data = NULL; |
|
channel->sock_funcs = NULL; |
|
channel->sock_func_cb_data = NULL; |
|
channel->resolvconf_path = NULL; |
|
|
|
channel->last_server = 0; |
|
channel->last_timeout_processed = (time_t)now.tv_sec; |
|
|
|
memset(&channel->local_dev_name, 0, sizeof(channel->local_dev_name)); |
|
channel->local_ip4 = 0; |
|
memset(&channel->local_ip6, 0, sizeof(channel->local_ip6)); |
|
|
|
/* Initialize our lists of queries */ |
|
ares__init_list_head(&(channel->all_queries)); |
|
for (i = 0; i < ARES_QID_TABLE_SIZE; i++) |
|
{ |
|
ares__init_list_head(&(channel->queries_by_qid[i])); |
|
} |
|
for (i = 0; i < ARES_TIMEOUT_TABLE_SIZE; i++) |
|
{ |
|
ares__init_list_head(&(channel->queries_by_timeout[i])); |
|
} |
|
|
|
/* Initialize configuration by each of the four sources, from highest |
|
* precedence to lowest. |
|
*/ |
|
|
|
status = init_by_options(channel, options, optmask); |
|
if (status != ARES_SUCCESS) { |
|
DEBUGF(fprintf(stderr, "Error: init_by_options failed: %s\n", |
|
ares_strerror(status))); |
|
/* If we fail to apply user-specified options, fail the whole init process */ |
|
goto done; |
|
} |
|
status = init_by_environment(channel); |
|
if (status != ARES_SUCCESS) |
|
DEBUGF(fprintf(stderr, "Error: init_by_environment failed: %s\n", |
|
ares_strerror(status))); |
|
if (status == ARES_SUCCESS) { |
|
status = init_by_resolv_conf(channel); |
|
if (status != ARES_SUCCESS) |
|
DEBUGF(fprintf(stderr, "Error: init_by_resolv_conf failed: %s\n", |
|
ares_strerror(status))); |
|
} |
|
|
|
/* |
|
* No matter what failed or succeeded, seed defaults to provide |
|
* useful behavior for things that we missed. |
|
*/ |
|
status = init_by_defaults(channel); |
|
if (status != ARES_SUCCESS) |
|
DEBUGF(fprintf(stderr, "Error: init_by_defaults failed: %s\n", |
|
ares_strerror(status))); |
|
|
|
/* Generate random key */ |
|
|
|
if (status == ARES_SUCCESS) { |
|
status = init_id_key(&channel->id_key, ARES_ID_KEY_LEN); |
|
if (status == ARES_SUCCESS) |
|
channel->next_id = ares__generate_new_id(&channel->id_key); |
|
else |
|
DEBUGF(fprintf(stderr, "Error: init_id_key failed: %s\n", |
|
ares_strerror(status))); |
|
} |
|
|
|
done: |
|
if (status != ARES_SUCCESS) |
|
{ |
|
/* Something failed; clean up memory we may have allocated. */ |
|
if (channel->servers) |
|
ares_free(channel->servers); |
|
if (channel->ndomains != -1) |
|
ares_strsplit_free(channel->domains, channel->ndomains); |
|
if (channel->sortlist) |
|
ares_free(channel->sortlist); |
|
if(channel->lookups) |
|
ares_free(channel->lookups); |
|
if(channel->resolvconf_path) |
|
ares_free(channel->resolvconf_path); |
|
ares_free(channel); |
|
return status; |
|
} |
|
|
|
/* Trim to one server if ARES_FLAG_PRIMARY is set. */ |
|
if ((channel->flags & ARES_FLAG_PRIMARY) && channel->nservers > 1) |
|
channel->nservers = 1; |
|
|
|
ares__init_servers_state(channel); |
|
|
|
*channelptr = channel; |
|
return ARES_SUCCESS; |
|
} |
|
|
|
/* ares_dup() duplicates a channel handle with all its options and returns a |
|
new channel handle */ |
|
int ares_dup(ares_channel *dest, ares_channel src) |
|
{ |
|
struct ares_options opts; |
|
struct ares_addr_port_node *servers; |
|
int non_v4_default_port = 0; |
|
int i, rc; |
|
int optmask; |
|
|
|
*dest = NULL; /* in case of failure return NULL explicitly */ |
|
|
|
/* First get the options supported by the old ares_save_options() function, |
|
which is most of them */ |
|
rc = ares_save_options(src, &opts, &optmask); |
|
if(rc) |
|
{ |
|
ares_destroy_options(&opts); |
|
return rc; |
|
} |
|
|
|
/* Then create the new channel with those options */ |
|
rc = ares_init_options(dest, &opts, optmask); |
|
|
|
/* destroy the options copy to not leak any memory */ |
|
ares_destroy_options(&opts); |
|
|
|
if(rc) |
|
return rc; |
|
|
|
/* Now clone the options that ares_save_options() doesn't support. */ |
|
(*dest)->sock_create_cb = src->sock_create_cb; |
|
(*dest)->sock_create_cb_data = src->sock_create_cb_data; |
|
(*dest)->sock_config_cb = src->sock_config_cb; |
|
(*dest)->sock_config_cb_data = src->sock_config_cb_data; |
|
(*dest)->sock_funcs = src->sock_funcs; |
|
(*dest)->sock_func_cb_data = src->sock_func_cb_data; |
|
|
|
strncpy((*dest)->local_dev_name, src->local_dev_name, |
|
sizeof((*dest)->local_dev_name)); |
|
(*dest)->local_ip4 = src->local_ip4; |
|
memcpy((*dest)->local_ip6, src->local_ip6, sizeof(src->local_ip6)); |
|
|
|
/* Full name server cloning required if there is a non-IPv4, or non-default port, nameserver */ |
|
for (i = 0; i < src->nservers; i++) |
|
{ |
|
if ((src->servers[i].addr.family != AF_INET) || |
|
(src->servers[i].addr.udp_port != 0) || |
|
(src->servers[i].addr.tcp_port != 0)) { |
|
non_v4_default_port++; |
|
break; |
|
} |
|
} |
|
if (non_v4_default_port) { |
|
rc = ares_get_servers_ports(src, &servers); |
|
if (rc != ARES_SUCCESS) { |
|
ares_destroy(*dest); |
|
*dest = NULL; |
|
return rc; |
|
} |
|
rc = ares_set_servers_ports(*dest, servers); |
|
ares_free_data(servers); |
|
if (rc != ARES_SUCCESS) { |
|
ares_destroy(*dest); |
|
*dest = NULL; |
|
return rc; |
|
} |
|
} |
|
|
|
return ARES_SUCCESS; /* everything went fine */ |
|
} |
|
|
|
/* Save options from initialized channel */ |
|
int ares_save_options(ares_channel channel, struct ares_options *options, |
|
int *optmask) |
|
{ |
|
int i, j; |
|
int ipv4_nservers = 0; |
|
|
|
/* Zero everything out */ |
|
memset(options, 0, sizeof(struct ares_options)); |
|
|
|
if (!ARES_CONFIG_CHECK(channel)) |
|
return ARES_ENODATA; |
|
|
|
/* Traditionally the optmask wasn't saved in the channel struct so it was |
|
recreated here. ROTATE is the first option that has no struct field of |
|
its own in the public config struct */ |
|
(*optmask) = (ARES_OPT_FLAGS|ARES_OPT_TRIES|ARES_OPT_NDOTS| |
|
ARES_OPT_UDP_PORT|ARES_OPT_TCP_PORT|ARES_OPT_SOCK_STATE_CB| |
|
ARES_OPT_SERVERS|ARES_OPT_DOMAINS|ARES_OPT_LOOKUPS| |
|
ARES_OPT_SORTLIST|ARES_OPT_TIMEOUTMS); |
|
(*optmask) |= (channel->rotate ? ARES_OPT_ROTATE : ARES_OPT_NOROTATE); |
|
|
|
if (channel->resolvconf_path) |
|
(*optmask) |= ARES_OPT_RESOLVCONF; |
|
|
|
/* Copy easy stuff */ |
|
options->flags = channel->flags; |
|
|
|
/* We return full millisecond resolution but that's only because we don't |
|
set the ARES_OPT_TIMEOUT anymore, only the new ARES_OPT_TIMEOUTMS */ |
|
options->timeout = channel->timeout; |
|
options->tries = channel->tries; |
|
options->ndots = channel->ndots; |
|
options->udp_port = ntohs(aresx_sitous(channel->udp_port)); |
|
options->tcp_port = ntohs(aresx_sitous(channel->tcp_port)); |
|
options->sock_state_cb = channel->sock_state_cb; |
|
options->sock_state_cb_data = channel->sock_state_cb_data; |
|
|
|
/* Copy IPv4 servers that use the default port */ |
|
if (channel->nservers) { |
|
for (i = 0; i < channel->nservers; i++) |
|
{ |
|
if ((channel->servers[i].addr.family == AF_INET) && |
|
(channel->servers[i].addr.udp_port == 0) && |
|
(channel->servers[i].addr.tcp_port == 0)) |
|
ipv4_nservers++; |
|
} |
|
if (ipv4_nservers) { |
|
options->servers = ares_malloc(ipv4_nservers * sizeof(struct in_addr)); |
|
if (!options->servers) |
|
return ARES_ENOMEM; |
|
for (i = j = 0; i < channel->nservers; i++) |
|
{ |
|
if ((channel->servers[i].addr.family == AF_INET) && |
|
(channel->servers[i].addr.udp_port == 0) && |
|
(channel->servers[i].addr.tcp_port == 0)) |
|
memcpy(&options->servers[j++], |
|
&channel->servers[i].addr.addrV4, |
|
sizeof(channel->servers[i].addr.addrV4)); |
|
} |
|
} |
|
} |
|
options->nservers = ipv4_nservers; |
|
|
|
/* copy domains */ |
|
if (channel->ndomains) { |
|
options->domains = ares_malloc(channel->ndomains * sizeof(char *)); |
|
if (!options->domains) |
|
return ARES_ENOMEM; |
|
|
|
for (i = 0; i < channel->ndomains; i++) |
|
{ |
|
options->ndomains = i; |
|
options->domains[i] = ares_strdup(channel->domains[i]); |
|
if (!options->domains[i]) |
|
return ARES_ENOMEM; |
|
} |
|
} |
|
options->ndomains = channel->ndomains; |
|
|
|
/* copy lookups */ |
|
if (channel->lookups) { |
|
options->lookups = ares_strdup(channel->lookups); |
|
if (!options->lookups && channel->lookups) |
|
return ARES_ENOMEM; |
|
} |
|
|
|
/* copy sortlist */ |
|
if (channel->nsort) { |
|
options->sortlist = ares_malloc(channel->nsort * sizeof(struct apattern)); |
|
if (!options->sortlist) |
|
return ARES_ENOMEM; |
|
for (i = 0; i < channel->nsort; i++) |
|
options->sortlist[i] = channel->sortlist[i]; |
|
} |
|
options->nsort = channel->nsort; |
|
|
|
/* copy path for resolv.conf file */ |
|
if (channel->resolvconf_path) { |
|
options->resolvconf_path = ares_strdup(channel->resolvconf_path); |
|
if (!options->resolvconf_path) |
|
return ARES_ENOMEM; |
|
} |
|
|
|
return ARES_SUCCESS; |
|
} |
|
|
|
static int init_by_options(ares_channel channel, |
|
const struct ares_options *options, |
|
int optmask) |
|
{ |
|
int i; |
|
|
|
/* Easy stuff. */ |
|
if ((optmask & ARES_OPT_FLAGS) && channel->flags == -1) |
|
channel->flags = options->flags; |
|
if ((optmask & ARES_OPT_TIMEOUTMS) && channel->timeout == -1) |
|
channel->timeout = options->timeout; |
|
else if ((optmask & ARES_OPT_TIMEOUT) && channel->timeout == -1) |
|
channel->timeout = options->timeout * 1000; |
|
if ((optmask & ARES_OPT_TRIES) && channel->tries == -1) |
|
channel->tries = options->tries; |
|
if ((optmask & ARES_OPT_NDOTS) && channel->ndots == -1) |
|
channel->ndots = options->ndots; |
|
if ((optmask & ARES_OPT_ROTATE) && channel->rotate == -1) |
|
channel->rotate = 1; |
|
if ((optmask & ARES_OPT_NOROTATE) && channel->rotate == -1) |
|
channel->rotate = 0; |
|
if ((optmask & ARES_OPT_UDP_PORT) && channel->udp_port == -1) |
|
channel->udp_port = htons(options->udp_port); |
|
if ((optmask & ARES_OPT_TCP_PORT) && channel->tcp_port == -1) |
|
channel->tcp_port = htons(options->tcp_port); |
|
if ((optmask & ARES_OPT_SOCK_STATE_CB) && channel->sock_state_cb == NULL) |
|
{ |
|
channel->sock_state_cb = options->sock_state_cb; |
|
channel->sock_state_cb_data = options->sock_state_cb_data; |
|
} |
|
if ((optmask & ARES_OPT_SOCK_SNDBUF) |
|
&& channel->socket_send_buffer_size == -1) |
|
channel->socket_send_buffer_size = options->socket_send_buffer_size; |
|
if ((optmask & ARES_OPT_SOCK_RCVBUF) |
|
&& channel->socket_receive_buffer_size == -1) |
|
channel->socket_receive_buffer_size = options->socket_receive_buffer_size; |
|
|
|
if ((optmask & ARES_OPT_EDNSPSZ) && channel->ednspsz == -1) |
|
channel->ednspsz = options->ednspsz; |
|
|
|
/* Copy the IPv4 servers, if given. */ |
|
if ((optmask & ARES_OPT_SERVERS) && channel->nservers == -1) |
|
{ |
|
/* Avoid zero size allocations at any cost */ |
|
if (options->nservers > 0) |
|
{ |
|
channel->servers = |
|
ares_malloc(options->nservers * sizeof(struct server_state)); |
|
if (!channel->servers) |
|
return ARES_ENOMEM; |
|
for (i = 0; i < options->nservers; i++) |
|
{ |
|
channel->servers[i].addr.family = AF_INET; |
|
channel->servers[i].addr.udp_port = 0; |
|
channel->servers[i].addr.tcp_port = 0; |
|
memcpy(&channel->servers[i].addr.addrV4, |
|
&options->servers[i], |
|
sizeof(channel->servers[i].addr.addrV4)); |
|
} |
|
} |
|
channel->nservers = options->nservers; |
|
} |
|
|
|
/* Copy the domains, if given. Keep channel->ndomains consistent so |
|
* we can clean up in case of error. |
|
*/ |
|
if ((optmask & ARES_OPT_DOMAINS) && channel->ndomains == -1) |
|
{ |
|
/* Avoid zero size allocations at any cost */ |
|
if (options->ndomains > 0) |
|
{ |
|
channel->domains = ares_malloc(options->ndomains * sizeof(char *)); |
|
if (!channel->domains) |
|
return ARES_ENOMEM; |
|
for (i = 0; i < options->ndomains; i++) |
|
{ |
|
channel->ndomains = i; |
|
channel->domains[i] = ares_strdup(options->domains[i]); |
|
if (!channel->domains[i]) |
|
return ARES_ENOMEM; |
|
} |
|
} |
|
channel->ndomains = options->ndomains; |
|
} |
|
|
|
/* Set lookups, if given. */ |
|
if ((optmask & ARES_OPT_LOOKUPS) && !channel->lookups) |
|
{ |
|
channel->lookups = ares_strdup(options->lookups); |
|
if (!channel->lookups) |
|
return ARES_ENOMEM; |
|
} |
|
|
|
/* copy sortlist */ |
|
if ((optmask & ARES_OPT_SORTLIST) && (channel->nsort == -1)) { |
|
if (options->nsort > 0) { |
|
channel->sortlist = ares_malloc(options->nsort * sizeof(struct apattern)); |
|
if (!channel->sortlist) |
|
return ARES_ENOMEM; |
|
for (i = 0; i < options->nsort; i++) |
|
channel->sortlist[i] = options->sortlist[i]; |
|
} |
|
channel->nsort = options->nsort; |
|
} |
|
|
|
/* Set path for resolv.conf file, if given. */ |
|
if ((optmask & ARES_OPT_RESOLVCONF) && !channel->resolvconf_path) |
|
{ |
|
channel->resolvconf_path = ares_strdup(options->resolvconf_path); |
|
if (!channel->resolvconf_path && options->resolvconf_path) |
|
return ARES_ENOMEM; |
|
} |
|
|
|
channel->optmask = optmask; |
|
|
|
return ARES_SUCCESS; |
|
} |
|
|
|
static int init_by_environment(ares_channel channel) |
|
{ |
|
const char *localdomain, *res_options; |
|
int status; |
|
|
|
localdomain = getenv("LOCALDOMAIN"); |
|
if (localdomain && channel->ndomains == -1) |
|
{ |
|
status = set_search(channel, localdomain); |
|
if (status != ARES_SUCCESS) |
|
return status; |
|
} |
|
|
|
res_options = getenv("RES_OPTIONS"); |
|
if (res_options) |
|
{ |
|
status = set_options(channel, res_options); |
|
if (status != ARES_SUCCESS) |
|
return status; /* LCOV_EXCL_LINE: set_options() never fails */ |
|
} |
|
|
|
return ARES_SUCCESS; |
|
} |
|
|
|
#ifdef WIN32 |
|
/* |
|
* get_REG_SZ() |
|
* |
|
* Given a 'hKey' handle to an open registry key and a 'leafKeyName' pointer |
|
* to the name of the registry leaf key to be queried, fetch it's string |
|
* value and return a pointer in *outptr to a newly allocated memory area |
|
* holding it as a null-terminated string. |
|
* |
|
* Returns 0 and nullifies *outptr upon inability to return a string value. |
|
* |
|
* Returns 1 and sets *outptr when returning a dynamically allocated string. |
|
* |
|
* Supported on Windows NT 3.5 and newer. |
|
*/ |
|
static int get_REG_SZ(HKEY hKey, const char *leafKeyName, char **outptr) |
|
{ |
|
DWORD size = 0; |
|
int res; |
|
|
|
*outptr = NULL; |
|
|
|
/* Find out size of string stored in registry */ |
|
res = RegQueryValueExA(hKey, leafKeyName, 0, NULL, NULL, &size); |
|
if ((res != ERROR_SUCCESS && res != ERROR_MORE_DATA) || !size) |
|
return 0; |
|
|
|
/* Allocate buffer of indicated size plus one given that string |
|
might have been stored without null termination */ |
|
*outptr = ares_malloc(size+1); |
|
if (!*outptr) |
|
return 0; |
|
|
|
/* Get the value for real */ |
|
res = RegQueryValueExA(hKey, leafKeyName, 0, NULL, |
|
(unsigned char *)*outptr, &size); |
|
if ((res != ERROR_SUCCESS) || (size == 1)) |
|
{ |
|
ares_free(*outptr); |
|
*outptr = NULL; |
|
return 0; |
|
} |
|
|
|
/* Null terminate buffer allways */ |
|
*(*outptr + size) = '\0'; |
|
|
|
return 1; |
|
} |
|
|
|
/* |
|
* get_REG_SZ_9X() |
|
* |
|
* Functionally identical to get_REG_SZ() |
|
* |
|
* Supported on Windows 95, 98 and ME. |
|
*/ |
|
static int get_REG_SZ_9X(HKEY hKey, const char *leafKeyName, char **outptr) |
|
{ |
|
DWORD dataType = 0; |
|
DWORD size = 0; |
|
int res; |
|
|
|
*outptr = NULL; |
|
|
|
/* Find out size of string stored in registry */ |
|
res = RegQueryValueExA(hKey, leafKeyName, 0, &dataType, NULL, &size); |
|
if ((res != ERROR_SUCCESS && res != ERROR_MORE_DATA) || !size) |
|
return 0; |
|
|
|
/* Allocate buffer of indicated size plus one given that string |
|
might have been stored without null termination */ |
|
*outptr = ares_malloc(size+1); |
|
if (!*outptr) |
|
return 0; |
|
|
|
/* Get the value for real */ |
|
res = RegQueryValueExA(hKey, leafKeyName, 0, &dataType, |
|
(unsigned char *)*outptr, &size); |
|
if ((res != ERROR_SUCCESS) || (size == 1)) |
|
{ |
|
ares_free(*outptr); |
|
*outptr = NULL; |
|
return 0; |
|
} |
|
|
|
/* Null terminate buffer allways */ |
|
*(*outptr + size) = '\0'; |
|
|
|
return 1; |
|
} |
|
|
|
/* |
|
* get_enum_REG_SZ() |
|
* |
|
* Given a 'hKeyParent' handle to an open registry key and a 'leafKeyName' |
|
* pointer to the name of the registry leaf key to be queried, parent key |
|
* is enumerated searching in child keys for given leaf key name and its |
|
* associated string value. When located, this returns a pointer in *outptr |
|
* to a newly allocated memory area holding it as a null-terminated string. |
|
* |
|
* Returns 0 and nullifies *outptr upon inability to return a string value. |
|
* |
|
* Returns 1 and sets *outptr when returning a dynamically allocated string. |
|
* |
|
* Supported on Windows NT 3.5 and newer. |
|
*/ |
|
static int get_enum_REG_SZ(HKEY hKeyParent, const char *leafKeyName, |
|
char **outptr) |
|
{ |
|
char enumKeyName[256]; |
|
DWORD enumKeyNameBuffSize; |
|
DWORD enumKeyIdx = 0; |
|
HKEY hKeyEnum; |
|
int gotString; |
|
int res; |
|
|
|
*outptr = NULL; |
|
|
|
for(;;) |
|
{ |
|
enumKeyNameBuffSize = sizeof(enumKeyName); |
|
res = RegEnumKeyExA(hKeyParent, enumKeyIdx++, enumKeyName, |
|
&enumKeyNameBuffSize, 0, NULL, NULL, NULL); |
|
if (res != ERROR_SUCCESS) |
|
break; |
|
res = RegOpenKeyExA(hKeyParent, enumKeyName, 0, KEY_QUERY_VALUE, |
|
&hKeyEnum); |
|
if (res != ERROR_SUCCESS) |
|
continue; |
|
gotString = get_REG_SZ(hKeyEnum, leafKeyName, outptr); |
|
RegCloseKey(hKeyEnum); |
|
if (gotString) |
|
break; |
|
} |
|
|
|
if (!*outptr) |
|
return 0; |
|
|
|
return 1; |
|
} |
|
|
|
/* |
|
* get_DNS_Registry_9X() |
|
* |
|
* Functionally identical to get_DNS_Registry() |
|
* |
|
* Implementation supports Windows 95, 98 and ME. |
|
*/ |
|
static int get_DNS_Registry_9X(char **outptr) |
|
{ |
|
HKEY hKey_VxD_MStcp; |
|
int gotString; |
|
int res; |
|
|
|
*outptr = NULL; |
|
|
|
res = RegOpenKeyExA(HKEY_LOCAL_MACHINE, WIN_NS_9X, 0, KEY_READ, |
|
&hKey_VxD_MStcp); |
|
if (res != ERROR_SUCCESS) |
|
return 0; |
|
|
|
gotString = get_REG_SZ_9X(hKey_VxD_MStcp, NAMESERVER, outptr); |
|
RegCloseKey(hKey_VxD_MStcp); |
|
|
|
if (!gotString || !*outptr) |
|
return 0; |
|
|
|
return 1; |
|
} |
|
|
|
/* |
|
* get_DNS_Registry_NT() |
|
* |
|
* Functionally identical to get_DNS_Registry() |
|
* |
|
* Refs: Microsoft Knowledge Base articles KB120642 and KB314053. |
|
* |
|
* Implementation supports Windows NT 3.5 and newer. |
|
*/ |
|
static int get_DNS_Registry_NT(char **outptr) |
|
{ |
|
HKEY hKey_Interfaces = NULL; |
|
HKEY hKey_Tcpip_Parameters; |
|
int gotString; |
|
int res; |
|
|
|
*outptr = NULL; |
|
|
|
res = RegOpenKeyExA(HKEY_LOCAL_MACHINE, WIN_NS_NT_KEY, 0, KEY_READ, |
|
&hKey_Tcpip_Parameters); |
|
if (res != ERROR_SUCCESS) |
|
return 0; |
|
|
|
/* |
|
** Global DNS settings override adapter specific parameters when both |
|
** are set. Additionally static DNS settings override DHCP-configured |
|
** parameters when both are set. |
|
*/ |
|
|
|
/* Global DNS static parameters */ |
|
gotString = get_REG_SZ(hKey_Tcpip_Parameters, NAMESERVER, outptr); |
|
if (gotString) |
|
goto done; |
|
|
|
/* Global DNS DHCP-configured parameters */ |
|
gotString = get_REG_SZ(hKey_Tcpip_Parameters, DHCPNAMESERVER, outptr); |
|
if (gotString) |
|
goto done; |
|
|
|
/* Try adapter specific parameters */ |
|
res = RegOpenKeyExA(hKey_Tcpip_Parameters, "Interfaces", 0, |
|
KEY_QUERY_VALUE | KEY_ENUMERATE_SUB_KEYS, |
|
&hKey_Interfaces); |
|
if (res != ERROR_SUCCESS) |
|
{ |
|
hKey_Interfaces = NULL; |
|
goto done; |
|
} |
|
|
|
/* Adapter specific DNS static parameters */ |
|
gotString = get_enum_REG_SZ(hKey_Interfaces, NAMESERVER, outptr); |
|
if (gotString) |
|
goto done; |
|
|
|
/* Adapter specific DNS DHCP-configured parameters */ |
|
gotString = get_enum_REG_SZ(hKey_Interfaces, DHCPNAMESERVER, outptr); |
|
|
|
done: |
|
if (hKey_Interfaces) |
|
RegCloseKey(hKey_Interfaces); |
|
|
|
RegCloseKey(hKey_Tcpip_Parameters); |
|
|
|
if (!gotString || !*outptr) |
|
return 0; |
|
|
|
return 1; |
|
} |
|
|
|
/* |
|
* get_DNS_Registry() |
|
* |
|
* Locates DNS info in the registry. When located, this returns a pointer |
|
* in *outptr to a newly allocated memory area holding a null-terminated |
|
* string with a space or comma seperated list of DNS IP addresses. |
|
* |
|
* Returns 0 and nullifies *outptr upon inability to return DNSes string. |
|
* |
|
* Returns 1 and sets *outptr when returning a dynamically allocated string. |
|
*/ |
|
static int get_DNS_Registry(char **outptr) |
|
{ |
|
win_platform platform; |
|
int gotString = 0; |
|
|
|
*outptr = NULL; |
|
|
|
platform = ares__getplatform(); |
|
|
|
if (platform == WIN_NT) |
|
gotString = get_DNS_Registry_NT(outptr); |
|
else if (platform == WIN_9X) |
|
gotString = get_DNS_Registry_9X(outptr); |
|
|
|
if (!gotString) |
|
return 0; |
|
|
|
return 1; |
|
} |
|
|
|
static void commanjoin(char** dst, const char* const src, const size_t len) |
|
{ |
|
char *newbuf; |
|
size_t newsize; |
|
|
|
/* 1 for terminating 0 and 2 for , and terminating 0 */ |
|
newsize = len + (*dst ? (strlen(*dst) + 2) : 1); |
|
newbuf = ares_realloc(*dst, newsize); |
|
if (!newbuf) |
|
return; |
|
if (*dst == NULL) |
|
*newbuf = '\0'; |
|
*dst = newbuf; |
|
if (strlen(*dst) != 0) |
|
strcat(*dst, ","); |
|
strncat(*dst, src, len); |
|
} |
|
|
|
/* |
|
* commajoin() |
|
* |
|
* RTF code. |
|
*/ |
|
static void commajoin(char **dst, const char *src) |
|
{ |
|
commanjoin(dst, src, strlen(src)); |
|
} |
|
|
|
/* |
|
* get_DNS_NetworkParams() |
|
* |
|
* Locates DNS info using GetNetworkParams() function from the Internet |
|
* Protocol Helper (IP Helper) API. When located, this returns a pointer |
|
* in *outptr to a newly allocated memory area holding a null-terminated |
|
* string with a space or comma seperated list of DNS IP addresses. |
|
* |
|
* Returns 0 and nullifies *outptr upon inability to return DNSes string. |
|
* |
|
* Returns 1 and sets *outptr when returning a dynamically allocated string. |
|
* |
|
* Implementation supports Windows 98 and newer. |
|
* |
|
* Note: Ancient PSDK required in order to build a W98 target. |
|
*/ |
|
static int get_DNS_NetworkParams(char **outptr) |
|
{ |
|
FIXED_INFO *fi, *newfi; |
|
struct ares_addr namesrvr; |
|
char *txtaddr; |
|
IP_ADDR_STRING *ipAddr; |
|
int res; |
|
DWORD size = sizeof (*fi); |
|
|
|
*outptr = NULL; |
|
|
|
/* Verify run-time availability of GetNetworkParams() */ |
|
if (ares_fpGetNetworkParams == ZERO_NULL) |
|
return 0; |
|
|
|
fi = ares_malloc(size); |
|
if (!fi) |
|
return 0; |
|
|
|
res = (*ares_fpGetNetworkParams) (fi, &size); |
|
if ((res != ERROR_BUFFER_OVERFLOW) && (res != ERROR_SUCCESS)) |
|
goto done; |
|
|
|
newfi = ares_realloc(fi, size); |
|
if (!newfi) |
|
goto done; |
|
|
|
fi = newfi; |
|
res = (*ares_fpGetNetworkParams) (fi, &size); |
|
if (res != ERROR_SUCCESS) |
|
goto done; |
|
|
|
for (ipAddr = &fi->DnsServerList; ipAddr; ipAddr = ipAddr->Next) |
|
{ |
|
txtaddr = &ipAddr->IpAddress.String[0]; |
|
|
|
/* Validate converting textual address to binary format. */ |
|
if (ares_inet_pton(AF_INET, txtaddr, &namesrvr.addrV4) == 1) |
|
{ |
|
if ((namesrvr.addrV4.S_un.S_addr == INADDR_ANY) || |
|
(namesrvr.addrV4.S_un.S_addr == INADDR_NONE)) |
|
continue; |
|
} |
|
else if (ares_inet_pton(AF_INET6, txtaddr, &namesrvr.addrV6) == 1) |
|
{ |
|
if (memcmp(&namesrvr.addrV6, &ares_in6addr_any, |
|
sizeof(namesrvr.addrV6)) == 0) |
|
continue; |
|
} |
|
else |
|
continue; |
|
|
|
commajoin(outptr, txtaddr); |
|
|
|
if (!*outptr) |
|
break; |
|
} |
|
|
|
done: |
|
if (fi) |
|
ares_free(fi); |
|
|
|
if (!*outptr) |
|
return 0; |
|
|
|
return 1; |
|
} |
|
|
|
static BOOL ares_IsWindowsVistaOrGreater(void) |
|
{ |
|
OSVERSIONINFO vinfo; |
|
memset(&vinfo, 0, sizeof(vinfo)); |
|
vinfo.dwOSVersionInfoSize = sizeof(vinfo); |
|
#ifdef _MSC_VER |
|
#pragma warning(push) |
|
#pragma warning(disable:4996) /* warning C4996: 'GetVersionExW': was declared deprecated */ |
|
#endif |
|
if (!GetVersionEx(&vinfo) || vinfo.dwMajorVersion < 6) |
|
return FALSE; |
|
return TRUE; |
|
#ifdef _MSC_VER |
|
#pragma warning(pop) |
|
#endif |
|
} |
|
|
|
/* A structure to hold the string form of IPv4 and IPv6 addresses so we can |
|
* sort them by a metric. |
|
*/ |
|
typedef struct |
|
{ |
|
/* The metric we sort them by. */ |
|
ULONG metric; |
|
|
|
/* Original index of the item, used as a secondary sort parameter to make |
|
* qsort() stable if the metrics are equal */ |
|
size_t orig_idx; |
|
|
|
/* Room enough for the string form of any IPv4 or IPv6 address that |
|
* ares_inet_ntop() will create. Based on the existing c-ares practice. |
|
*/ |
|
char text[sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")]; |
|
} Address; |
|
|
|
/* Sort Address values \a left and \a right by metric, returning the usual |
|
* indicators for qsort(). |
|
*/ |
|
static int compareAddresses(const void *arg1, |
|
const void *arg2) |
|
{ |
|
const Address * const left = arg1; |
|
const Address * const right = arg2; |
|
/* Lower metric the more preferred */ |
|
if(left->metric < right->metric) return -1; |
|
if(left->metric > right->metric) return 1; |
|
/* If metrics are equal, lower original index more preferred */ |
|
if(left->orig_idx < right->orig_idx) return -1; |
|
if(left->orig_idx > right->orig_idx) return 1; |
|
return 0; |
|
} |
|
|
|
/* There can be multiple routes to "the Internet". And there can be different |
|
* DNS servers associated with each of the interfaces that offer those routes. |
|
* We have to assume that any DNS server can serve any request. But, some DNS |
|
* servers may only respond if requested over their associated interface. But |
|
* we also want to use "the preferred route to the Internet" whenever possible |
|
* (and not use DNS servers on a non-preferred route even by forcing request |
|
* to go out on the associated non-preferred interface). i.e. We want to use |
|
* the DNS servers associated with the same interface that we would use to |
|
* make a general request to anything else. |
|
* |
|
* But, Windows won't sort the DNS servers by the metrics associated with the |
|
* routes and interfaces _even_ though it obviously sends IP packets based on |
|
* those same routes and metrics. So, we must do it ourselves. |
|
* |
|
* So, we sort the DNS servers by the same metric values used to determine how |
|
* an outgoing IP packet will go, thus effectively using the DNS servers |
|
* associated with the interface that the DNS requests themselves will |
|
* travel. This gives us optimal routing and avoids issues where DNS servers |
|
* won't respond to requests that don't arrive via some specific subnetwork |
|
* (and thus some specific interface). |
|
* |
|
* This function computes the metric we use to sort. On the interface |
|
* identified by \a luid, it determines the best route to \a dest and combines |
|
* that route's metric with \a interfaceMetric to compute a metric for the |
|
* destination address on that interface. This metric can be used as a weight |
|
* to sort the DNS server addresses associated with each interface (lower is |
|
* better). |
|
* |
|
* Note that by restricting the route search to the specific interface with |
|
* which the DNS servers are associated, this function asks the question "What |
|
* is the metric for sending IP packets to this DNS server?" which allows us |
|
* to sort the DNS servers correctly. |
|
*/ |
|
static ULONG getBestRouteMetric(IF_LUID * const luid, /* Can't be const :( */ |
|
const SOCKADDR_INET * const dest, |
|
const ULONG interfaceMetric) |
|
{ |
|
/* On this interface, get the best route to that destination. */ |
|
MIB_IPFORWARD_ROW2 row; |
|
SOCKADDR_INET ignored; |
|
if(!ares_fpGetBestRoute2 || |
|
ares_fpGetBestRoute2(/* The interface to use. The index is ignored since we are |
|
* passing a LUID. |
|
*/ |
|
luid, 0, |
|
/* No specific source address. */ |
|
NULL, |
|
/* Our destination address. */ |
|
dest, |
|
/* No options. */ |
|
0, |
|
/* The route row. */ |
|
&row, |
|
/* The best source address, which we don't need. */ |
|
&ignored) != NO_ERROR |
|
/* If the metric is "unused" (-1) or too large for us to add the two |
|
* metrics, use the worst possible, thus sorting this last. |
|
*/ |
|
|| row.Metric == (ULONG)-1 |
|
|| row.Metric > ((ULONG)-1) - interfaceMetric) { |
|
/* Return the worst possible metric. */ |
|
return (ULONG)-1; |
|
} |
|
|
|
/* Return the metric value from that row, plus the interface metric. |
|
* |
|
* See |
|
* http://msdn.microsoft.com/en-us/library/windows/desktop/aa814494(v=vs.85).aspx |
|
* which describes the combination as a "sum". |
|
*/ |
|
return row.Metric + interfaceMetric; |
|
} |
|
|
|
/* |
|
* get_DNS_AdaptersAddresses() |
|
* |
|
* Locates DNS info using GetAdaptersAddresses() function from the Internet |
|
* Protocol Helper (IP Helper) API. When located, this returns a pointer |
|
* in *outptr to a newly allocated memory area holding a null-terminated |
|
* string with a space or comma seperated list of DNS IP addresses. |
|
* |
|
* Returns 0 and nullifies *outptr upon inability to return DNSes string. |
|
* |
|
* Returns 1 and sets *outptr when returning a dynamically allocated string. |
|
* |
|
* Implementation supports Windows XP and newer. |
|
*/ |
|
#define IPAA_INITIAL_BUF_SZ 15 * 1024 |
|
#define IPAA_MAX_TRIES 3 |
|
static int get_DNS_AdaptersAddresses(char **outptr) |
|
{ |
|
IP_ADAPTER_DNS_SERVER_ADDRESS *ipaDNSAddr; |
|
IP_ADAPTER_ADDRESSES *ipaa, *newipaa, *ipaaEntry; |
|
ULONG ReqBufsz = IPAA_INITIAL_BUF_SZ; |
|
ULONG Bufsz = IPAA_INITIAL_BUF_SZ; |
|
ULONG AddrFlags = 0; |
|
int trying = IPAA_MAX_TRIES; |
|
int res; |
|
|
|
/* The capacity of addresses, in elements. */ |
|
size_t addressesSize; |
|
/* The number of elements in addresses. */ |
|
size_t addressesIndex = 0; |
|
/* The addresses we will sort. */ |
|
Address *addresses; |
|
|
|
union { |
|
struct sockaddr *sa; |
|
struct sockaddr_in *sa4; |
|
struct sockaddr_in6 *sa6; |
|
} namesrvr; |
|
|
|
*outptr = NULL; |
|
|
|
/* Verify run-time availability of GetAdaptersAddresses() */ |
|
if (ares_fpGetAdaptersAddresses == ZERO_NULL) |
|
return 0; |
|
|
|
ipaa = ares_malloc(Bufsz); |
|
if (!ipaa) |
|
return 0; |
|
|
|
/* Start with enough room for a few DNS server addresses and we'll grow it |
|
* as we encounter more. |
|
*/ |
|
addressesSize = 4; |
|
addresses = (Address*)ares_malloc(sizeof(Address) * addressesSize); |
|
if(addresses == NULL) { |
|
/* We need room for at least some addresses to function. */ |
|
ares_free(ipaa); |
|
return 0; |
|
} |
|
|
|
/* Usually this call suceeds with initial buffer size */ |
|
res = (*ares_fpGetAdaptersAddresses) (AF_UNSPEC, AddrFlags, NULL, |
|
ipaa, &ReqBufsz); |
|
if ((res != ERROR_BUFFER_OVERFLOW) && (res != ERROR_SUCCESS)) |
|
goto done; |
|
|
|
while ((res == ERROR_BUFFER_OVERFLOW) && (--trying)) |
|
{ |
|
if (Bufsz < ReqBufsz) |
|
{ |
|
newipaa = ares_realloc(ipaa, ReqBufsz); |
|
if (!newipaa) |
|
goto done; |
|
Bufsz = ReqBufsz; |
|
ipaa = newipaa; |
|
} |
|
res = (*ares_fpGetAdaptersAddresses) (AF_UNSPEC, AddrFlags, NULL, |
|
ipaa, &ReqBufsz); |
|
if (res == ERROR_SUCCESS) |
|
break; |
|
} |
|
if (res != ERROR_SUCCESS) |
|
goto done; |
|
|
|
for (ipaaEntry = ipaa; ipaaEntry; ipaaEntry = ipaaEntry->Next) |
|
{ |
|
if(ipaaEntry->OperStatus != IfOperStatusUp) |
|
continue; |
|
|
|
/* For each interface, find any associated DNS servers as IPv4 or IPv6 |
|
* addresses. For each found address, find the best route to that DNS |
|
* server address _on_ _that_ _interface_ (at this moment in time) and |
|
* compute the resulting total metric, just as Windows routing will do. |
|
* Then, sort all the addresses found by the metric. |
|
*/ |
|
for (ipaDNSAddr = ipaaEntry->FirstDnsServerAddress; |
|
ipaDNSAddr; |
|
ipaDNSAddr = ipaDNSAddr->Next) |
|
{ |
|
namesrvr.sa = ipaDNSAddr->Address.lpSockaddr; |
|
|
|
if (namesrvr.sa->sa_family == AF_INET) |
|
{ |
|
if ((namesrvr.sa4->sin_addr.S_un.S_addr == INADDR_ANY) || |
|
(namesrvr.sa4->sin_addr.S_un.S_addr == INADDR_NONE)) |
|
continue; |
|
|
|
/* Allocate room for another address, if necessary, else skip. */ |
|
if(addressesIndex == addressesSize) { |
|
const size_t newSize = addressesSize + 4; |
|
Address * const newMem = |
|
(Address*)ares_realloc(addresses, sizeof(Address) * newSize); |
|
if(newMem == NULL) { |
|
continue; |
|
} |
|
addresses = newMem; |
|
addressesSize = newSize; |
|
} |
|
|
|
/* Vista required for Luid or Ipv4Metric */ |
|
if (ares_IsWindowsVistaOrGreater()) |
|
{ |
|
/* Save the address as the next element in addresses. */ |
|
addresses[addressesIndex].metric = |
|
getBestRouteMetric(&ipaaEntry->Luid, |
|
(SOCKADDR_INET*)(namesrvr.sa), |
|
ipaaEntry->Ipv4Metric); |
|
} |
|
else |
|
{ |
|
addresses[addressesIndex].metric = (ULONG)-1; |
|
} |
|
|
|
/* Record insertion index to make qsort stable */ |
|
addresses[addressesIndex].orig_idx = addressesIndex; |
|
|
|
if (! ares_inet_ntop(AF_INET, &namesrvr.sa4->sin_addr, |
|
addresses[addressesIndex].text, |
|
sizeof(addresses[0].text))) { |
|
continue; |
|
} |
|
++addressesIndex; |
|
} |
|
else if (namesrvr.sa->sa_family == AF_INET6) |
|
{ |
|
if (memcmp(&namesrvr.sa6->sin6_addr, &ares_in6addr_any, |
|
sizeof(namesrvr.sa6->sin6_addr)) == 0) |
|
continue; |
|
|
|
/* Allocate room for another address, if necessary, else skip. */ |
|
if(addressesIndex == addressesSize) { |
|
const size_t newSize = addressesSize + 4; |
|
Address * const newMem = |
|
(Address*)ares_realloc(addresses, sizeof(Address) * newSize); |
|
if(newMem == NULL) { |
|
continue; |
|
} |
|
addresses = newMem; |
|
addressesSize = newSize; |
|
} |
|
|
|
/* Vista required for Luid or Ipv4Metric */ |
|
if (ares_IsWindowsVistaOrGreater()) |
|
{ |
|
/* Save the address as the next element in addresses. */ |
|
addresses[addressesIndex].metric = |
|
getBestRouteMetric(&ipaaEntry->Luid, |
|
(SOCKADDR_INET*)(namesrvr.sa), |
|
ipaaEntry->Ipv6Metric); |
|
} |
|
else |
|
{ |
|
addresses[addressesIndex].metric = (ULONG)-1; |
|
} |
|
|
|
/* Record insertion index to make qsort stable */ |
|
addresses[addressesIndex].orig_idx = addressesIndex; |
|
|
|
if (! ares_inet_ntop(AF_INET6, &namesrvr.sa6->sin6_addr, |
|
addresses[addressesIndex].text, |
|
sizeof(addresses[0].text))) { |
|
continue; |
|
} |
|
++addressesIndex; |
|
} |
|
else { |
|
/* Skip non-IPv4/IPv6 addresses completely. */ |
|
continue; |
|
} |
|
} |
|
} |
|
|
|
/* Sort all of the textual addresses by their metric (and original index if |
|
* metrics are equal). */ |
|
qsort(addresses, addressesIndex, sizeof(*addresses), compareAddresses); |
|
|
|
/* Join them all into a single string, removing duplicates. */ |
|
{ |
|
size_t i; |
|
for(i = 0; i < addressesIndex; ++i) { |
|
size_t j; |
|
/* Look for this address text appearing previously in the results. */ |
|
for(j = 0; j < i; ++j) { |
|
if(strcmp(addresses[j].text, addresses[i].text) == 0) { |
|
break; |
|
} |
|
} |
|
/* Iff we didn't emit this address already, emit it now. */ |
|
if(j == i) { |
|
/* Add that to outptr (if we can). */ |
|
commajoin(outptr, addresses[i].text); |
|
} |
|
} |
|
} |
|
|
|
done: |
|
ares_free(addresses); |
|
|
|
if (ipaa) |
|
ares_free(ipaa); |
|
|
|
if (!*outptr) { |
|
return 0; |
|
} |
|
|
|
return 1; |
|
} |
|
|
|
/* |
|
* get_DNS_Windows() |
|
* |
|
* Locates DNS info from Windows employing most suitable methods available at |
|
* run-time no matter which Windows version it is. When located, this returns |
|
* a pointer in *outptr to a newly allocated memory area holding a string with |
|
* a space or comma seperated list of DNS IP addresses, null-terminated. |
|
* |
|
* Returns 0 and nullifies *outptr upon inability to return DNSes string. |
|
* |
|
* Returns 1 and sets *outptr when returning a dynamically allocated string. |
|
* |
|
* Implementation supports Windows 95 and newer. |
|
*/ |
|
static int get_DNS_Windows(char **outptr) |
|
{ |
|
/* Try using IP helper API GetAdaptersAddresses(). IPv4 + IPv6, also sorts |
|
* DNS servers by interface route metrics to try to use the best DNS server. */ |
|
if (get_DNS_AdaptersAddresses(outptr)) |
|
return 1; |
|
|
|
/* Try using IP helper API GetNetworkParams(). IPv4 only. */ |
|
if (get_DNS_NetworkParams(outptr)) |
|
return 1; |
|
|
|
/* Fall-back to registry information */ |
|
return get_DNS_Registry(outptr); |
|
} |
|
|
|
/* |
|
* get_SuffixList_Windows() |
|
* |
|
* Reads the "DNS Suffix Search List" from registry and writes the list items |
|
* whitespace separated to outptr. If the Search List is empty, the |
|
* "Primary Dns Suffix" is written to outptr. |
|
* |
|
* Returns 0 and nullifies *outptr upon inability to return the suffix list. |
|
* |
|
* Returns 1 and sets *outptr when returning a dynamically allocated string. |
|
* |
|
* Implementation supports Windows Server 2003 and newer |
|
*/ |
|
static int get_SuffixList_Windows(char **outptr) |
|
{ |
|
HKEY hKey, hKeyEnum; |
|
char keyName[256]; |
|
DWORD keyNameBuffSize; |
|
DWORD keyIdx = 0; |
|
char *p = NULL; |
|
|
|
*outptr = NULL; |
|
|
|
if (ares__getplatform() != WIN_NT) |
|
return 0; |
|
|
|
/* 1. Global DNS Suffix Search List */ |
|
if (RegOpenKeyExA(HKEY_LOCAL_MACHINE, WIN_NS_NT_KEY, 0, |
|
KEY_READ, &hKey) == ERROR_SUCCESS) |
|
{ |
|
get_REG_SZ(hKey, SEARCHLIST_KEY, outptr); |
|
if (get_REG_SZ(hKey, DOMAIN_KEY, &p)) |
|
{ |
|
commajoin(outptr, p); |
|
ares_free(p); |
|
p = NULL; |
|
} |
|
RegCloseKey(hKey); |
|
} |
|
|
|
if (RegOpenKeyExA(HKEY_LOCAL_MACHINE, WIN_NT_DNSCLIENT, 0, |
|
KEY_READ, &hKey) == ERROR_SUCCESS) |
|
{ |
|
if (get_REG_SZ(hKey, SEARCHLIST_KEY, &p)) |
|
{ |
|
commajoin(outptr, p); |
|
ares_free(p); |
|
p = NULL; |
|
} |
|
RegCloseKey(hKey); |
|
} |
|
|
|
/* 2. Connection Specific Search List composed of: |
|
* a. Primary DNS Suffix */ |
|
if (RegOpenKeyExA(HKEY_LOCAL_MACHINE, WIN_DNSCLIENT, 0, |
|
KEY_READ, &hKey) == ERROR_SUCCESS) |
|
{ |
|
if (get_REG_SZ(hKey, PRIMARYDNSSUFFIX_KEY, &p)) |
|
{ |
|
commajoin(outptr, p); |
|
ares_free(p); |
|
p = NULL; |
|
} |
|
RegCloseKey(hKey); |
|
} |
|
|
|
/* b. Interface SearchList, Domain, DhcpDomain */ |
|
if (RegOpenKeyExA(HKEY_LOCAL_MACHINE, WIN_NS_NT_KEY "\\" INTERFACES_KEY, 0, |
|
KEY_READ, &hKey) == ERROR_SUCCESS) |
|
{ |
|
for(;;) |
|
{ |
|
keyNameBuffSize = sizeof(keyName); |
|
if (RegEnumKeyExA(hKey, keyIdx++, keyName, &keyNameBuffSize, |
|
0, NULL, NULL, NULL) |
|
!= ERROR_SUCCESS) |
|
break; |
|
if (RegOpenKeyExA(hKey, keyName, 0, KEY_QUERY_VALUE, &hKeyEnum) |
|
!= ERROR_SUCCESS) |
|
continue; |
|
/* p can be comma separated (SearchList) */ |
|
if (get_REG_SZ(hKeyEnum, SEARCHLIST_KEY, &p)) |
|
{ |
|
commajoin(outptr, p); |
|
ares_free(p); |
|
p = NULL; |
|
} |
|
if (get_REG_SZ(hKeyEnum, DOMAIN_KEY, &p)) |
|
{ |
|
commajoin(outptr, p); |
|
ares_free(p); |
|
p = NULL; |
|
} |
|
if (get_REG_SZ(hKeyEnum, DHCPDOMAIN_KEY, &p)) |
|
{ |
|
commajoin(outptr, p); |
|
ares_free(p); |
|
p = NULL; |
|
} |
|
RegCloseKey(hKeyEnum); |
|
} |
|
RegCloseKey(hKey); |
|
} |
|
|
|
return *outptr != NULL; |
|
} |
|
|
|
#endif |
|
|
|
static int init_by_resolv_conf(ares_channel channel) |
|
{ |
|
#if !defined(ANDROID) && !defined(__ANDROID__) && !defined(WATT32) && \ |
|
!defined(CARES_USE_LIBRESOLV) |
|
char *line = NULL; |
|
#endif |
|
int status = -1, nservers = 0, nsort = 0; |
|
struct server_state *servers = NULL; |
|
struct apattern *sortlist = NULL; |
|
|
|
#ifdef WIN32 |
|
|
|
if (channel->nservers > -1) /* don't override ARES_OPT_SERVER */ |
|
return ARES_SUCCESS; |
|
|
|
if (get_DNS_Windows(&line)) |
|
{ |
|
status = config_nameserver(&servers, &nservers, line); |
|
ares_free(line); |
|
} |
|
|
|
if (channel->ndomains == -1 && get_SuffixList_Windows(&line)) |
|
{ |
|
status = set_search(channel, line); |
|
ares_free(line); |
|
} |
|
|
|
if (status == ARES_SUCCESS) |
|
status = ARES_EOF; |
|
else |
|
/* Catch the case when all the above checks fail (which happens when there |
|
is no network card or the cable is unplugged) */ |
|
status = ARES_EFILE; |
|
|
|
#elif defined(__riscos__) |
|
|
|
/* Under RISC OS, name servers are listed in the |
|
system variable Inet$Resolvers, space separated. */ |
|
|
|
line = getenv("Inet$Resolvers"); |
|
status = ARES_EOF; |
|
if (line) { |
|
char *resolvers = ares_strdup(line), *pos, *space; |
|
|
|
if (!resolvers) |
|
return ARES_ENOMEM; |
|
|
|
pos = resolvers; |
|
do { |
|
space = strchr(pos, ' '); |
|
if (space) |
|
*space = '\0'; |
|
status = config_nameserver(&servers, &nservers, pos); |
|
if (status != ARES_SUCCESS) |
|
break; |
|
pos = space + 1; |
|
} while (space); |
|
|
|
if (status == ARES_SUCCESS) |
|
status = ARES_EOF; |
|
|
|
ares_free(resolvers); |
|
} |
|
|
|
#elif defined(WATT32) |
|
int i; |
|
|
|
sock_init(); |
|
for (i = 0; def_nameservers[i]; i++) |
|
; |
|
if (i == 0) |
|
return ARES_SUCCESS; /* use localhost DNS server */ |
|
|
|
nservers = i; |
|
servers = ares_malloc(sizeof(struct server_state)); |
|
if (!servers) |
|
return ARES_ENOMEM; |
|
memset(servers, 0, sizeof(struct server_state)); |
|
|
|
for (i = 0; def_nameservers[i]; i++) |
|
{ |
|
servers[i].addr.addrV4.s_addr = htonl(def_nameservers[i]); |
|
servers[i].addr.family = AF_INET; |
|
servers[i].addr.udp_port = 0; |
|
servers[i].addr.tcp_port = 0; |
|
} |
|
status = ARES_EOF; |
|
|
|
#elif defined(ANDROID) || defined(__ANDROID__) |
|
unsigned int i; |
|
char **dns_servers; |
|
char *domains; |
|
size_t num_servers; |
|
|
|
/* Use the Android connectivity manager to get a list |
|
* of DNS servers. As of Android 8 (Oreo) net.dns# |
|
* system properties are no longer available. Google claims this |
|
* improves privacy. Apps now need the ACCESS_NETWORK_STATE |
|
* permission and must use the ConnectivityManager which |
|
* is Java only. */ |
|
dns_servers = ares_get_android_server_list(MAX_DNS_PROPERTIES, &num_servers); |
|
if (dns_servers != NULL) |
|
{ |
|
for (i = 0; i < num_servers; i++) |
|
{ |
|
status = config_nameserver(&servers, &nservers, dns_servers[i]); |
|
if (status != ARES_SUCCESS) |
|
break; |
|
status = ARES_EOF; |
|
} |
|
for (i = 0; i < num_servers; i++) |
|
{ |
|
ares_free(dns_servers[i]); |
|
} |
|
ares_free(dns_servers); |
|
} |
|
if (channel->ndomains == -1) |
|
{ |
|
domains = ares_get_android_search_domains_list(); |
|
set_search(channel, domains); |
|
ares_free(domains); |
|
} |
|
|
|
# ifdef HAVE___SYSTEM_PROPERTY_GET |
|
/* Old way using the system property still in place as |
|
* a fallback. Older android versions can still use this. |
|
* it's possible for older apps not not have added the new |
|
* permission and we want to try to avoid breaking those. |
|
* |
|
* We'll only run this if we don't have any dns servers |
|
* because this will get the same ones (if it works). */ |
|
if (status != ARES_EOF) { |
|
char propname[PROP_NAME_MAX]; |
|
char propvalue[PROP_VALUE_MAX]=""; |
|
for (i = 1; i <= MAX_DNS_PROPERTIES; i++) { |
|
snprintf(propname, sizeof(propname), "%s%u", DNS_PROP_NAME_PREFIX, i); |
|
if (__system_property_get(propname, propvalue) < 1) { |
|
status = ARES_EOF; |
|
break; |
|
} |
|
|
|
status = config_nameserver(&servers, &nservers, propvalue); |
|
if (status != ARES_SUCCESS) |
|
break; |
|
status = ARES_EOF; |
|
} |
|
} |
|
# endif /* HAVE___SYSTEM_PROPERTY_GET */ |
|
#elif defined(CARES_USE_LIBRESOLV) |
|
struct __res_state res; |
|
memset(&res, 0, sizeof(res)); |
|
int result = res_ninit(&res); |
|
if (result == 0 && (res.options & RES_INIT)) { |
|
status = ARES_EOF; |
|
|
|
if (channel->nservers == -1) { |
|
union res_sockaddr_union addr[MAXNS]; |
|
int nscount = res_getservers(&res, addr, MAXNS); |
|
for (int i = 0; i < nscount; ++i) { |
|
char str[INET6_ADDRSTRLEN]; |
|
int config_status; |
|
sa_family_t family = addr[i].sin.sin_family; |
|
if (family == AF_INET) { |
|
ares_inet_ntop(family, &addr[i].sin.sin_addr, str, sizeof(str)); |
|
} else if (family == AF_INET6) { |
|
ares_inet_ntop(family, &addr[i].sin6.sin6_addr, str, sizeof(str)); |
|
} else { |
|
continue; |
|
} |
|
|
|
config_status = config_nameserver(&servers, &nservers, str); |
|
if (config_status != ARES_SUCCESS) { |
|
status = config_status; |
|
break; |
|
} |
|
} |
|
} |
|
if (channel->ndomains == -1) { |
|
int entries = 0; |
|
while ((entries < MAXDNSRCH) && res.dnsrch[entries]) |
|
entries++; |
|
|
|
channel->domains = ares_malloc(entries * sizeof(char *)); |
|
if (!channel->domains) { |
|
status = ARES_ENOMEM; |
|
} else { |
|
channel->ndomains = entries; |
|
for (int i = 0; i < channel->ndomains; ++i) { |
|
channel->domains[i] = ares_strdup(res.dnsrch[i]); |
|
if (!channel->domains[i]) |
|
status = ARES_ENOMEM; |
|
} |
|
} |
|
} |
|
if (channel->ndots == -1) |
|
channel->ndots = res.ndots; |
|
if (channel->tries == -1) |
|
channel->tries = res.retry; |
|
if (channel->rotate == -1) |
|
channel->rotate = res.options & RES_ROTATE; |
|
if (channel->timeout == -1) |
|
channel->timeout = res.retrans * 1000; |
|
|
|
res_ndestroy(&res); |
|
} |
|
#else |
|
{ |
|
char *p; |
|
FILE *fp; |
|
size_t linesize; |
|
int error; |
|
int update_domains; |
|
const char *resolvconf_path; |
|
|
|
/* Don't read resolv.conf and friends if we don't have to */ |
|
if (ARES_CONFIG_CHECK(channel)) |
|
return ARES_SUCCESS; |
|
|
|
/* Only update search domains if they're not already specified */ |
|
update_domains = (channel->ndomains == -1); |
|
|
|
/* Support path for resolvconf filename set by ares_init_options */ |
|
if(channel->resolvconf_path) { |
|
resolvconf_path = channel->resolvconf_path; |
|
} else { |
|
resolvconf_path = PATH_RESOLV_CONF; |
|
} |
|
|
|
fp = fopen(resolvconf_path, "r"); |
|
if (fp) { |
|
while ((status = ares__read_line(fp, &line, &linesize)) == ARES_SUCCESS) |
|
{ |
|
if ((p = try_config(line, "domain", ';')) && update_domains) |
|
status = config_domain(channel, p); |
|
else if ((p = try_config(line, "lookup", ';')) && !channel->lookups) |
|
status = config_lookup(channel, p, "bind", NULL, "file"); |
|
else if ((p = try_config(line, "search", ';')) && update_domains) |
|
status = set_search(channel, p); |
|
else if ((p = try_config(line, "nameserver", ';')) && |
|
channel->nservers == -1) |
|
status = config_nameserver(&servers, &nservers, p); |
|
else if ((p = try_config(line, "sortlist", ';')) && |
|
channel->nsort == -1) |
|
status = config_sortlist(&sortlist, &nsort, p); |
|
else if ((p = try_config(line, "options", ';'))) |
|
status = set_options(channel, p); |
|
else |
|
status = ARES_SUCCESS; |
|
if (status != ARES_SUCCESS) |
|
break; |
|
} |
|
fclose(fp); |
|
} |
|
else { |
|
error = ERRNO; |
|
switch(error) { |
|
case ENOENT: |
|
case ESRCH: |
|
status = ARES_EOF; |
|
break; |
|
default: |
|
DEBUGF(fprintf(stderr, "fopen() failed with error: %d %s\n", |
|
error, strerror(error))); |
|
DEBUGF(fprintf(stderr, "Error opening file: %s\n", PATH_RESOLV_CONF)); |
|
status = ARES_EFILE; |
|
} |
|
} |
|
|
|
if ((status == ARES_EOF) && (!channel->lookups)) { |
|
/* Many systems (Solaris, Linux, BSD's) use nsswitch.conf */ |
|
fp = fopen("/etc/nsswitch.conf", "r"); |
|
if (fp) { |
|
while ((status = ares__read_line(fp, &line, &linesize)) == |
|
ARES_SUCCESS) |
|
{ |
|
if ((p = try_config(line, "hosts:", '\0')) && !channel->lookups) |
|
(void)config_lookup(channel, p, "dns", "resolve", "files"); |
|
} |
|
fclose(fp); |
|
} |
|
else { |
|
error = ERRNO; |
|
switch(error) { |
|
case ENOENT: |
|
case ESRCH: |
|
break; |
|
default: |
|
DEBUGF(fprintf(stderr, "fopen() failed with error: %d %s\n", |
|
error, strerror(error))); |
|
DEBUGF(fprintf(stderr, "Error opening file: %s\n", |
|
"/etc/nsswitch.conf")); |
|
} |
|
|
|
/* ignore error, maybe we will get luck in next if clause */ |
|
status = ARES_EOF; |
|
} |
|
} |
|
|
|
if ((status == ARES_EOF) && (!channel->lookups)) { |
|
/* Linux / GNU libc 2.x and possibly others have host.conf */ |
|
fp = fopen("/etc/host.conf", "r"); |
|
if (fp) { |
|
while ((status = ares__read_line(fp, &line, &linesize)) == |
|
ARES_SUCCESS) |
|
{ |
|
if ((p = try_config(line, "order", '\0')) && !channel->lookups) |
|
/* ignore errors */ |
|
(void)config_lookup(channel, p, "bind", NULL, "hosts"); |
|
} |
|
fclose(fp); |
|
} |
|
else { |
|
error = ERRNO; |
|
switch(error) { |
|
case ENOENT: |
|
case ESRCH: |
|
break; |
|
default: |
|
DEBUGF(fprintf(stderr, "fopen() failed with error: %d %s\n", |
|
error, strerror(error))); |
|
DEBUGF(fprintf(stderr, "Error opening file: %s\n", |
|
"/etc/host.conf")); |
|
} |
|
|
|
/* ignore error, maybe we will get luck in next if clause */ |
|
status = ARES_EOF; |
|
} |
|
} |
|
|
|
if ((status == ARES_EOF) && (!channel->lookups)) { |
|
/* Tru64 uses /etc/svc.conf */ |
|
fp = fopen("/etc/svc.conf", "r"); |
|
if (fp) { |
|
while ((status = ares__read_line(fp, &line, &linesize)) == |
|
ARES_SUCCESS) |
|
{ |
|
if ((p = try_config(line, "hosts=", '\0')) && !channel->lookups) |
|
/* ignore errors */ |
|
(void)config_lookup(channel, p, "bind", NULL, "local"); |
|
} |
|
fclose(fp); |
|
} |
|
else { |
|
error = ERRNO; |
|
switch(error) { |
|
case ENOENT: |
|
case ESRCH: |
|
break; |
|
default: |
|
DEBUGF(fprintf(stderr, "fopen() failed with error: %d %s\n", |
|
error, strerror(error))); |
|
DEBUGF(fprintf(stderr, "Error opening file: %s\n", "/etc/svc.conf")); |
|
} |
|
|
|
/* ignore error, default value will be chosen for `channel->lookups` */ |
|
status = ARES_EOF; |
|
} |
|
} |
|
|
|
if(line) |
|
ares_free(line); |
|
} |
|
|
|
#endif |
|
|
|
/* Handle errors. */ |
|
if (status != ARES_EOF) |
|
{ |
|
if (servers != NULL) |
|
ares_free(servers); |
|
if (sortlist != NULL) |
|
ares_free(sortlist); |
|
return status; |
|
} |
|
|
|
/* If we got any name server entries, fill them in. */ |
|
if (servers) |
|
{ |
|
channel->servers = servers; |
|
channel->nservers = nservers; |
|
} |
|
|
|
/* If we got any sortlist entries, fill them in. */ |
|
if (sortlist) |
|
{ |
|
channel->sortlist = sortlist; |
|
channel->nsort = nsort; |
|
} |
|
|
|
return ARES_SUCCESS; |
|
} |
|
|
|
static int init_by_defaults(ares_channel channel) |
|
{ |
|
char *hostname = NULL; |
|
int rc = ARES_SUCCESS; |
|
#ifdef HAVE_GETHOSTNAME |
|
char *dot; |
|
#endif |
|
|
|
if (channel->flags == -1) |
|
channel->flags = 0; |
|
if (channel->timeout == -1) |
|
channel->timeout = DEFAULT_TIMEOUT; |
|
if (channel->tries == -1) |
|
channel->tries = DEFAULT_TRIES; |
|
if (channel->ndots == -1) |
|
channel->ndots = 1; |
|
if (channel->rotate == -1) |
|
channel->rotate = 0; |
|
if (channel->udp_port == -1) |
|
channel->udp_port = htons(NAMESERVER_PORT); |
|
if (channel->tcp_port == -1) |
|
channel->tcp_port = htons(NAMESERVER_PORT); |
|
|
|
if (channel->ednspsz == -1) |
|
channel->ednspsz = EDNSPACKETSZ; |
|
|
|
if (channel->nservers == -1) { |
|
/* If nobody specified servers, try a local named. */ |
|
channel->servers = ares_malloc(sizeof(struct server_state)); |
|
if (!channel->servers) { |
|
rc = ARES_ENOMEM; |
|
goto error; |
|
} |
|
channel->servers[0].addr.family = AF_INET; |
|
channel->servers[0].addr.addrV4.s_addr = htonl(INADDR_LOOPBACK); |
|
channel->servers[0].addr.udp_port = 0; |
|
channel->servers[0].addr.tcp_port = 0; |
|
channel->nservers = 1; |
|
} |
|
|
|
#if defined(USE_WINSOCK) |
|
#define toolong(x) (x == -1) && (SOCKERRNO == WSAEFAULT) |
|
#elif defined(ENAMETOOLONG) |
|
#define toolong(x) (x == -1) && ((SOCKERRNO == ENAMETOOLONG) || \ |
|
(SOCKERRNO == EINVAL)) |
|
#else |
|
#define toolong(x) (x == -1) && (SOCKERRNO == EINVAL) |
|
#endif |
|
|
|
if (channel->ndomains == -1) { |
|
/* Derive a default domain search list from the kernel hostname, |
|
* or set it to empty if the hostname isn't helpful. |
|
*/ |
|
#ifndef HAVE_GETHOSTNAME |
|
channel->ndomains = 0; /* default to none */ |
|
#else |
|
GETHOSTNAME_TYPE_ARG2 lenv = 64; |
|
size_t len = 64; |
|
int res; |
|
channel->ndomains = 0; /* default to none */ |
|
|
|
hostname = ares_malloc(len); |
|
if(!hostname) { |
|
rc = ARES_ENOMEM; |
|
goto error; |
|
} |
|
|
|
do { |
|
res = gethostname(hostname, lenv); |
|
|
|
if(toolong(res)) { |
|
char *p; |
|
len *= 2; |
|
lenv *= 2; |
|
p = ares_realloc(hostname, len); |
|
if(!p) { |
|
rc = ARES_ENOMEM; |
|
goto error; |
|
} |
|
hostname = p; |
|
continue; |
|
} |
|
else if(res) { |
|
/* Lets not treat a gethostname failure as critical, since we |
|
* are ok if gethostname doesn't even exist */ |
|
*hostname = '\0'; |
|
break; |
|
} |
|
|
|
} while (res != 0); |
|
|
|
dot = strchr(hostname, '.'); |
|
if (dot) { |
|
/* a dot was found */ |
|
channel->domains = ares_malloc(sizeof(char *)); |
|
if (!channel->domains) { |
|
rc = ARES_ENOMEM; |
|
goto error; |
|
} |
|
channel->domains[0] = ares_strdup(dot + 1); |
|
if (!channel->domains[0]) { |
|
rc = ARES_ENOMEM; |
|
goto error; |
|
} |
|
channel->ndomains = 1; |
|
} |
|
#endif |
|
} |
|
|
|
if (channel->nsort == -1) { |
|
channel->sortlist = NULL; |
|
channel->nsort = 0; |
|
} |
|
|
|
if (!channel->lookups) { |
|
channel->lookups = ares_strdup("fb"); |
|
if (!channel->lookups) |
|
rc = ARES_ENOMEM; |
|
} |
|
|
|
error: |
|
if(rc) { |
|
if(channel->servers) { |
|
ares_free(channel->servers); |
|
channel->servers = NULL; |
|
} |
|
|
|
if(channel->domains && channel->domains[0]) |
|
ares_free(channel->domains[0]); |
|
if(channel->domains) { |
|
ares_free(channel->domains); |
|
channel->domains = NULL; |
|
} |
|
|
|
if(channel->lookups) { |
|
ares_free(channel->lookups); |
|
channel->lookups = NULL; |
|
} |
|
|
|
if(channel->resolvconf_path) { |
|
ares_free(channel->resolvconf_path); |
|
channel->resolvconf_path = NULL; |
|
} |
|
} |
|
|
|
if(hostname) |
|
ares_free(hostname); |
|
|
|
return rc; |
|
} |
|
|
|
#if !defined(WIN32) && !defined(WATT32) && \ |
|
!defined(ANDROID) && !defined(__ANDROID__) && !defined(CARES_USE_LIBRESOLV) |
|
static int config_domain(ares_channel channel, char *str) |
|
{ |
|
char *q; |
|
|
|
/* Set a single search domain. */ |
|
q = str; |
|
while (*q && !ISSPACE(*q)) |
|
q++; |
|
*q = '\0'; |
|
return set_search(channel, str); |
|
} |
|
|
|
#if defined(__INTEL_COMPILER) && (__INTEL_COMPILER == 910) && \ |
|
defined(__OPTIMIZE__) && defined(__unix__) && defined(__i386__) |
|
/* workaround icc 9.1 optimizer issue */ |
|
# define vqualifier volatile |
|
#else |
|
# define vqualifier |
|
#endif |
|
|
|
static int config_lookup(ares_channel channel, const char *str, |
|
const char *bindch, const char *altbindch, |
|
const char *filech) |
|
{ |
|
char lookups[3], *l; |
|
const char *vqualifier p; |
|
int found; |
|
|
|
if (altbindch == NULL) |
|
altbindch = bindch; |
|
|
|
/* Set the lookup order. Only the first letter of each work |
|
* is relevant, and it has to be "b" for DNS or "f" for the |
|
* host file. Ignore everything else. |
|
*/ |
|
l = lookups; |
|
p = str; |
|
found = 0; |
|
while (*p) |
|
{ |
|
if ((*p == *bindch || *p == *altbindch || *p == *filech) && l < lookups + 2) { |
|
if (*p == *bindch || *p == *altbindch) *l++ = 'b'; |
|
else *l++ = 'f'; |
|
found = 1; |
|
} |
|
while (*p && !ISSPACE(*p) && (*p != ',')) |
|
p++; |
|
while (*p && (ISSPACE(*p) || (*p == ','))) |
|
p++; |
|
} |
|
if (!found) |
|
return ARES_ENOTINITIALIZED; |
|
*l = '\0'; |
|
channel->lookups = ares_strdup(lookups); |
|
return (channel->lookups) ? ARES_SUCCESS : ARES_ENOMEM; |
|
} |
|
#endif /* !WIN32 & !WATT32 & !ANDROID & !__ANDROID__ & !CARES_USE_LIBRESOLV */ |
|
|
|
#ifndef WATT32 |
|
/* Validate that the ip address matches the subnet (network base and network |
|
* mask) specified. Addresses are specified in standard Network Byte Order as |
|
* 16 bytes, and the netmask is 0 to 128 (bits). |
|
*/ |
|
static int ares_ipv6_subnet_matches(const unsigned char netbase[16], |
|
unsigned char netmask, |
|
const unsigned char ipaddr[16]) |
|
{ |
|
unsigned char mask[16] = { 0 }; |
|
unsigned char i; |
|
|
|
/* Misuse */ |
|
if (netmask > 128) |
|
return 0; |
|
|
|
/* Quickly set whole bytes */ |
|
memset(mask, 0xFF, netmask / 8); |
|
|
|
/* Set remaining bits */ |
|
if(netmask % 8) { |
|
mask[netmask / 8] = (unsigned char)(0xff << (8 - (netmask % 8))); |
|
} |
|
|
|
for (i=0; i<16; i++) { |
|
if ((netbase[i] & mask[i]) != (ipaddr[i] & mask[i])) |
|
return 0; |
|
} |
|
|
|
return 1; |
|
} |
|
|
|
/* Return true iff the IPv6 ipaddr is blacklisted. */ |
|
static int ares_ipv6_server_blacklisted(const unsigned char ipaddr[16]) |
|
{ |
|
/* A list of blacklisted IPv6 subnets. */ |
|
const struct { |
|
const unsigned char netbase[16]; |
|
unsigned char netmask; |
|
} blacklist[] = { |
|
/* fec0::/10 was deprecated by [RFC3879] in September 2004. Formerly a |
|
* Site-Local scoped address prefix. These are never valid DNS servers, |
|
* but are known to be returned at least sometimes on Windows and Android. |
|
*/ |
|
{ |
|
{ |
|
0xfe, 0xc0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, |
|
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 |
|
}, |
|
10 |
|
} |
|
}; |
|
size_t i; |
|
|
|
/* See if ipaddr matches any of the entries in the blacklist. */ |
|
for (i = 0; i < sizeof(blacklist) / sizeof(blacklist[0]); ++i) { |
|
if (ares_ipv6_subnet_matches( |
|
blacklist[i].netbase, blacklist[i].netmask, ipaddr)) |
|
return 1; |
|
} |
|
return 0; |
|
} |
|
|
|
/* Add the IPv4 or IPv6 nameservers in str (separated by commas) to the |
|
* servers list, updating servers and nservers as required. |
|
* |
|
* This will silently ignore blacklisted IPv6 nameservers as detected by |
|
* ares_ipv6_server_blacklisted(). |
|
* |
|
* Returns an error code on failure, else ARES_SUCCESS. |
|
*/ |
|
static int config_nameserver(struct server_state **servers, int *nservers, |
|
char *str) |
|
{ |
|
struct ares_addr host; |
|
struct server_state *newserv; |
|
char *p, *txtaddr; |
|
/* On Windows, there may be more than one nameserver specified in the same |
|
* registry key, so we parse input as a space or comma seperated list. |
|
*/ |
|
for (p = str; p;) |
|
{ |
|
/* Skip whitespace and commas. */ |
|
while (*p && (ISSPACE(*p) || (*p == ','))) |
|
p++; |
|
if (!*p) |
|
/* No more input, done. */ |
|
break; |
|
|
|
/* Pointer to start of IPv4 or IPv6 address part. */ |
|
txtaddr = p; |
|
|
|
/* Advance past this address. */ |
|
while (*p && !ISSPACE(*p) && (*p != ',')) |
|
p++; |
|
if (*p) |
|
/* Null terminate this address. */ |
|
*p++ = '\0'; |
|
else |
|
/* Reached end of input, done when this address is processed. */ |
|
p = NULL; |
|
|
|
/* Convert textual address to binary format. */ |
|
if (ares_inet_pton(AF_INET, txtaddr, &host.addrV4) == 1) |
|
host.family = AF_INET; |
|
else if (ares_inet_pton(AF_INET6, txtaddr, &host.addrV6) == 1 |
|
/* Silently skip blacklisted IPv6 servers. */ |
|
&& !ares_ipv6_server_blacklisted( |
|
(const unsigned char *)&host.addrV6)) |
|
host.family = AF_INET6; |
|
else |
|
continue; |
|
|
|
/* Resize servers state array. */ |
|
newserv = ares_realloc(*servers, (*nservers + 1) * |
|
sizeof(struct server_state)); |
|
if (!newserv) |
|
return ARES_ENOMEM; |
|
|
|
/* Store address data. */ |
|
newserv[*nservers].addr.family = host.family; |
|
newserv[*nservers].addr.udp_port = 0; |
|
newserv[*nservers].addr.tcp_port = 0; |
|
if (host.family == AF_INET) |
|
memcpy(&newserv[*nservers].addr.addrV4, &host.addrV4, |
|
sizeof(host.addrV4)); |
|
else |
|
memcpy(&newserv[*nservers].addr.addrV6, &host.addrV6, |
|
sizeof(host.addrV6)); |
|
|
|
/* Update arguments. */ |
|
*servers = newserv; |
|
*nservers += 1; |
|
} |
|
|
|
return ARES_SUCCESS; |
|
} |
|
#endif /* !WATT32 */ |
|
|
|
static int config_sortlist(struct apattern **sortlist, int *nsort, |
|
const char *str) |
|
{ |
|
struct apattern pat; |
|
const char *q; |
|
|
|
/* Add sortlist entries. */ |
|
while (*str && *str != ';') |
|
{ |
|
int bits; |
|
char ipbuf[16], ipbufpfx[32]; |
|
/* Find just the IP */ |
|
q = str; |
|
while (*q && *q != '/' && *q != ';' && !ISSPACE(*q)) |
|
q++; |
|
memcpy(ipbuf, str, q-str); |
|
ipbuf[q-str] = '\0'; |
|
/* Find the prefix */ |
|
if (*q == '/') |
|
{ |
|
const char *str2 = q+1; |
|
while (*q && *q != ';' && !ISSPACE(*q)) |
|
q++; |
|
memcpy(ipbufpfx, str, q-str); |
|
ipbufpfx[q-str] = '\0'; |
|
str = str2; |
|
} |
|
else |
|
ipbufpfx[0] = '\0'; |
|
/* Lets see if it is CIDR */ |
|
/* First we'll try IPv6 */ |
|
if ((bits = ares_inet_net_pton(AF_INET6, ipbufpfx[0] ? ipbufpfx : ipbuf, |
|
&pat.addrV6, |
|
sizeof(pat.addrV6))) > 0) |
|
{ |
|
pat.type = PATTERN_CIDR; |
|
pat.mask.bits = (unsigned short)bits; |
|
pat.family = AF_INET6; |
|
if (!sortlist_alloc(sortlist, nsort, &pat)) { |
|
ares_free(*sortlist); |
|
*sortlist = NULL; |
|
return ARES_ENOMEM; |
|
} |
|
} |
|
else if (ipbufpfx[0] && |
|
(bits = ares_inet_net_pton(AF_INET, ipbufpfx, &pat.addrV4, |
|
sizeof(pat.addrV4))) > 0) |
|
{ |
|
pat.type = PATTERN_CIDR; |
|
pat.mask.bits = (unsigned short)bits; |
|
pat.family = AF_INET; |
|
if (!sortlist_alloc(sortlist, nsort, &pat)) { |
|
ares_free(*sortlist); |
|
*sortlist = NULL; |
|
return ARES_ENOMEM; |
|
} |
|
} |
|
/* See if it is just a regular IP */ |
|
else if (ip_addr(ipbuf, q-str, &pat.addrV4) == 0) |
|
{ |
|
if (ipbufpfx[0]) |
|
{ |
|
memcpy(ipbuf, str, q-str); |
|
ipbuf[q-str] = '\0'; |
|
if (ip_addr(ipbuf, q-str, &pat.mask.addr4) != 0) |
|
natural_mask(&pat); |
|
} |
|
else |
|
natural_mask(&pat); |
|
pat.family = AF_INET; |
|
pat.type = PATTERN_MASK; |
|
if (!sortlist_alloc(sortlist, nsort, &pat)) { |
|
ares_free(*sortlist); |
|
*sortlist = NULL; |
|
return ARES_ENOMEM; |
|
} |
|
} |
|
else |
|
{ |
|
while (*q && *q != ';' && !ISSPACE(*q)) |
|
q++; |
|
} |
|
str = q; |
|
while (ISSPACE(*str)) |
|
str++; |
|
} |
|
|
|
return ARES_SUCCESS; |
|
} |
|
|
|
static int set_search(ares_channel channel, const char *str) |
|
{ |
|
size_t cnt; |
|
|
|
if(channel->ndomains != -1) { |
|
/* LCOV_EXCL_START: all callers check ndomains == -1 */ |
|
/* if we already have some domains present, free them first */ |
|
ares_strsplit_free(channel->domains, channel->ndomains); |
|
channel->domains = NULL; |
|
channel->ndomains = -1; |
|
} /* LCOV_EXCL_STOP */ |
|
|
|
channel->domains = ares_strsplit(str, ", ", 1, &cnt); |
|
channel->ndomains = (int)cnt; |
|
if (channel->domains == NULL || channel->ndomains == 0) { |
|
channel->domains = NULL; |
|
channel->ndomains = -1; |
|
} |
|
|
|
return ARES_SUCCESS; |
|
} |
|
|
|
static int set_options(ares_channel channel, const char *str) |
|
{ |
|
const char *p, *q, *val; |
|
|
|
p = str; |
|
while (*p) |
|
{ |
|
q = p; |
|
while (*q && !ISSPACE(*q)) |
|
q++; |
|
val = try_option(p, q, "ndots:"); |
|
if (val && channel->ndots == -1) |
|
channel->ndots = aresx_sltosi(strtol(val, NULL, 10)); |
|
val = try_option(p, q, "retrans:"); |
|
if (val && channel->timeout == -1) |
|
channel->timeout = aresx_sltosi(strtol(val, NULL, 10)); |
|
val = try_option(p, q, "retry:"); |
|
if (val && channel->tries == -1) |
|
channel->tries = aresx_sltosi(strtol(val, NULL, 10)); |
|
val = try_option(p, q, "rotate"); |
|
if (val && channel->rotate == -1) |
|
channel->rotate = 1; |
|
p = q; |
|
while (ISSPACE(*p)) |
|
p++; |
|
} |
|
|
|
return ARES_SUCCESS; |
|
} |
|
|
|
static const char *try_option(const char *p, const char *q, const char *opt) |
|
{ |
|
size_t len = strlen(opt); |
|
return ((size_t)(q - p) >= len && !strncmp(p, opt, len)) ? &p[len] : NULL; |
|
} |
|
|
|
#if !defined(WIN32) && !defined(WATT32) && \ |
|
!defined(ANDROID) && !defined(__ANDROID__) && !defined(CARES_USE_LIBRESOLV) |
|
static char *try_config(char *s, const char *opt, char scc) |
|
{ |
|
size_t len; |
|
char *p; |
|
char *q; |
|
|
|
if (!s || !opt) |
|
/* no line or no option */ |
|
return NULL; /* LCOV_EXCL_LINE */ |
|
|
|
/* Hash '#' character is always used as primary comment char, additionally |
|
a not-NUL secondary comment char will be considered when specified. */ |
|
|
|
/* trim line comment */ |
|
p = s; |
|
if(scc) |
|
while (*p && (*p != '#') && (*p != scc)) |
|
p++; |
|
else |
|
while (*p && (*p != '#')) |
|
p++; |
|
*p = '\0'; |
|
|
|
/* trim trailing whitespace */ |
|
q = p - 1; |
|
while ((q >= s) && ISSPACE(*q)) |
|
q--; |
|
*++q = '\0'; |
|
|
|
/* skip leading whitespace */ |
|
p = s; |
|
while (*p && ISSPACE(*p)) |
|
p++; |
|
|
|
if (!*p) |
|
/* empty line */ |
|
return NULL; |
|
|
|
if ((len = strlen(opt)) == 0) |
|
/* empty option */ |
|
return NULL; /* LCOV_EXCL_LINE */ |
|
|
|
if (strncmp(p, opt, len) != 0) |
|
/* line and option do not match */ |
|
return NULL; |
|
|
|
/* skip over given option name */ |
|
p += len; |
|
|
|
if (!*p) |
|
/* no option value */ |
|
return NULL; /* LCOV_EXCL_LINE */ |
|
|
|
if ((opt[len-1] != ':') && (opt[len-1] != '=') && !ISSPACE(*p)) |
|
/* whitespace between option name and value is mandatory |
|
for given option names which do not end with ':' or '=' */ |
|
return NULL; |
|
|
|
/* skip over whitespace */ |
|
while (*p && ISSPACE(*p)) |
|
p++; |
|
|
|
if (!*p) |
|
/* no option value */ |
|
return NULL; |
|
|
|
/* return pointer to option value */ |
|
return p; |
|
} |
|
#endif /* !WIN32 & !WATT32 & !ANDROID & !__ANDROID__ */ |
|
|
|
static int ip_addr(const char *ipbuf, ares_ssize_t len, struct in_addr *addr) |
|
{ |
|
|
|
/* Four octets and three periods yields at most 15 characters. */ |
|
if (len > 15) |
|
return -1; |
|
|
|
if (ares_inet_pton(AF_INET, ipbuf, addr) < 1) |
|
return -1; |
|
|
|
return 0; |
|
} |
|
|
|
static void natural_mask(struct apattern *pat) |
|
{ |
|
struct in_addr addr; |
|
|
|
/* Store a host-byte-order copy of pat in a struct in_addr. Icky, |
|
* but portable. |
|
*/ |
|
addr.s_addr = ntohl(pat->addrV4.s_addr); |
|
|
|
/* This is out of date in the CIDR world, but some people might |
|
* still rely on it. |
|
*/ |
|
if (IN_CLASSA(addr.s_addr)) |
|
pat->mask.addr4.s_addr = htonl(IN_CLASSA_NET); |
|
else if (IN_CLASSB(addr.s_addr)) |
|
pat->mask.addr4.s_addr = htonl(IN_CLASSB_NET); |
|
else |
|
pat->mask.addr4.s_addr = htonl(IN_CLASSC_NET); |
|
} |
|
|
|
static int sortlist_alloc(struct apattern **sortlist, int *nsort, |
|
struct apattern *pat) |
|
{ |
|
struct apattern *newsort; |
|
newsort = ares_realloc(*sortlist, (*nsort + 1) * sizeof(struct apattern)); |
|
if (!newsort) |
|
return 0; |
|
newsort[*nsort] = *pat; |
|
*sortlist = newsort; |
|
(*nsort)++; |
|
return 1; |
|
} |
|
|
|
/* initialize an rc4 key. If possible a cryptographically secure random key |
|
is generated using a suitable function (for example win32's RtlGenRandom as |
|
described in |
|
http://blogs.msdn.com/michael_howard/archive/2005/01/14/353379.aspx |
|
otherwise the code defaults to cross-platform albeit less secure mechanism |
|
using rand |
|
*/ |
|
static void randomize_key(unsigned char* key,int key_data_len) |
|
{ |
|
int randomized = 0; |
|
int counter=0; |
|
#ifdef WIN32 |
|
BOOLEAN res; |
|
if (ares_fpSystemFunction036) |
|
{ |
|
res = (*ares_fpSystemFunction036) (key, key_data_len); |
|
if (res) |
|
randomized = 1; |
|
} |
|
#else /* !WIN32 */ |
|
#ifdef RANDOM_FILE |
|
FILE *f = fopen(RANDOM_FILE, "rb"); |
|
if(f) { |
|
counter = aresx_uztosi(fread(key, 1, key_data_len, f)); |
|
fclose(f); |
|
} |
|
#endif |
|
#endif /* WIN32 */ |
|
|
|
if (!randomized) { |
|
for (;counter<key_data_len;counter++) |
|
key[counter]=(unsigned char)(rand() % 256); /* LCOV_EXCL_LINE */ |
|
} |
|
} |
|
|
|
static int init_id_key(rc4_key* key,int key_data_len) |
|
{ |
|
unsigned char index1; |
|
unsigned char index2; |
|
unsigned char* state; |
|
short counter; |
|
unsigned char *key_data_ptr = 0; |
|
|
|
key_data_ptr = ares_malloc(key_data_len); |
|
if (!key_data_ptr) |
|
return ARES_ENOMEM; |
|
memset(key_data_ptr, 0, key_data_len); |
|
|
|
state = &key->state[0]; |
|
for(counter = 0; counter < 256; counter++) |
|
/* unnecessary AND but it keeps some compilers happier */ |
|
state[counter] = (unsigned char)(counter & 0xff); |
|
randomize_key(key->state,key_data_len); |
|
key->x = 0; |
|
key->y = 0; |
|
index1 = 0; |
|
index2 = 0; |
|
for(counter = 0; counter < 256; counter++) |
|
{ |
|
index2 = (unsigned char)((key_data_ptr[index1] + state[counter] + |
|
index2) % 256); |
|
ARES_SWAP_BYTE(&state[counter], &state[index2]); |
|
|
|
index1 = (unsigned char)((index1 + 1) % key_data_len); |
|
} |
|
ares_free(key_data_ptr); |
|
return ARES_SUCCESS; |
|
} |
|
|
|
void ares_set_local_ip4(ares_channel channel, unsigned int local_ip) |
|
{ |
|
channel->local_ip4 = local_ip; |
|
} |
|
|
|
/* local_ip6 should be 16 bytes in length */ |
|
void ares_set_local_ip6(ares_channel channel, |
|
const unsigned char* local_ip6) |
|
{ |
|
memcpy(&channel->local_ip6, local_ip6, sizeof(channel->local_ip6)); |
|
} |
|
|
|
/* local_dev_name should be null terminated. */ |
|
void ares_set_local_dev(ares_channel channel, |
|
const char* local_dev_name) |
|
{ |
|
strncpy(channel->local_dev_name, local_dev_name, |
|
sizeof(channel->local_dev_name)); |
|
channel->local_dev_name[sizeof(channel->local_dev_name) - 1] = 0; |
|
} |
|
|
|
|
|
void ares_set_socket_callback(ares_channel channel, |
|
ares_sock_create_callback cb, |
|
void *data) |
|
{ |
|
channel->sock_create_cb = cb; |
|
channel->sock_create_cb_data = data; |
|
} |
|
|
|
void ares_set_socket_configure_callback(ares_channel channel, |
|
ares_sock_config_callback cb, |
|
void *data) |
|
{ |
|
channel->sock_config_cb = cb; |
|
channel->sock_config_cb_data = data; |
|
} |
|
|
|
void ares_set_socket_functions(ares_channel channel, |
|
const struct ares_socket_functions * funcs, |
|
void *data) |
|
{ |
|
channel->sock_funcs = funcs; |
|
channel->sock_func_cb_data = data; |
|
} |
|
|
|
int ares_set_sortlist(ares_channel channel, const char *sortstr) |
|
{ |
|
int nsort = 0; |
|
struct apattern *sortlist = NULL; |
|
int status; |
|
|
|
if (!channel) |
|
return ARES_ENODATA; |
|
|
|
status = config_sortlist(&sortlist, &nsort, sortstr); |
|
if (status == ARES_SUCCESS && sortlist) { |
|
if (channel->sortlist) |
|
ares_free(channel->sortlist); |
|
channel->sortlist = sortlist; |
|
channel->nsort = nsort; |
|
} |
|
return status; |
|
} |
|
|
|
void ares__init_servers_state(ares_channel channel) |
|
{ |
|
struct server_state *server; |
|
int i; |
|
|
|
for (i = 0; i < channel->nservers; i++) |
|
{ |
|
server = &channel->servers[i]; |
|
server->udp_socket = ARES_SOCKET_BAD; |
|
server->tcp_socket = ARES_SOCKET_BAD; |
|
server->tcp_connection_generation = ++channel->tcp_connection_generation; |
|
server->tcp_lenbuf_pos = 0; |
|
server->tcp_buffer_pos = 0; |
|
server->tcp_buffer = NULL; |
|
server->tcp_length = 0; |
|
server->qhead = NULL; |
|
server->qtail = NULL; |
|
ares__init_list_head(&server->queries_to_server); |
|
server->channel = channel; |
|
server->is_broken = 0; |
|
} |
|
}
|
|
|