diff --git a/libc/docs/OVERVIEW.TXT b/libc/docs/OVERVIEW.TXT index a0a349345..753e48a5b 100644 --- a/libc/docs/OVERVIEW.TXT +++ b/libc/docs/OVERVIEW.TXT @@ -282,9 +282,16 @@ DNS resolver: - read /system/etc/resolv.conf instead of /etc/resolv.conf - - get the list of servers and the search domains for this process's - current interface from the dns cache. This information is sent - from the framework via cache functions. + - read the list of servers from system properties. the code looks for + 'net.dns1', 'net.dns2', etc.. Each property should contain the IP + address of a DNS server. + + these properties are set/modified by other parts of the Android system + (e.g. the dhcpd daemon). + + the implementation also supports per-process DNS server list, using the + properties 'net.dns1.', 'net.dns2.', etc... Where stands + for the numerical ID of the current process. - when performing a query, use a properly randomized Query ID (instead of a incremented one), for increased security. diff --git a/libc/include/netdb.h b/libc/include/netdb.h index 3ea512c75..ead595435 100644 --- a/libc/include/netdb.h +++ b/libc/include/netdb.h @@ -207,13 +207,11 @@ void endprotoent(void); void endservent(void); void freehostent(struct hostent *); struct hostent *gethostbyaddr(const void *, socklen_t, int); -struct hostent *android_gethostbyaddrforiface(const void *, socklen_t, int, const char*); int gethostbyaddr_r(const void *, int, int, struct hostent *, char *, size_t, struct hostent **, int *); struct hostent *gethostbyname(const char *); int gethostbyname_r(const char *, struct hostent *, char *, size_t, struct hostent **, int *); struct hostent *gethostbyname2(const char *, int); int gethostbyname2_r(const char *, int, struct hostent *, char *, size_t, struct hostent **, int *); -struct hostent *android_gethostbynameforiface(const char *, int, const char *); struct hostent *gethostent(void); int gethostent_r(struct hostent *, char *, size_t, struct hostent **, int *); struct hostent *getipnodebyaddr(const void *, size_t, int, int *); @@ -241,9 +239,7 @@ void sethostent(int); void setnetent(int); void setprotoent(int); int getaddrinfo(const char *, const char *, const struct addrinfo *, struct addrinfo **); -int android_getaddrinfoforiface(const char *, const char *, const struct addrinfo *, const char *, struct addrinfo **); int getnameinfo(const struct sockaddr *, socklen_t, char *, size_t, char *, size_t, int); -int android_getnameinfoforiface(const struct sockaddr *, socklen_t, char *, size_t, char *, size_t, int, const char *); void freeaddrinfo(struct addrinfo *); const char *gai_strerror(int); void setnetgrent(const char *); diff --git a/libc/netbsd/gethnamaddr.c b/libc/netbsd/gethnamaddr.c index c59d1f1c8..9a9f6e240 100644 --- a/libc/netbsd/gethnamaddr.c +++ b/libc/netbsd/gethnamaddr.c @@ -56,7 +56,6 @@ #include #include -#include #include #include #include "arpa_nameser.h" @@ -70,7 +69,6 @@ #include #include #include -#include #ifndef LOG_AUTH # define LOG_AUTH 0 @@ -82,9 +80,6 @@ #include #include -// This should be synchronized to ResponseCode.h -static const int DnsProxyQueryResult = 222; - static const char const AskedForGot[] = "gethostby*.getanswer: asked for \"%s\", got \"%s\""; @@ -126,7 +121,7 @@ static struct hostent *_gethtbyname2(const char *, int); static int _dns_gethtbyaddr(void *, void *, va_list); static int _dns_gethtbyname(void *, void *, va_list); -static struct hostent *gethostbyname_internal(const char *, int, res_state, const char *); +static struct hostent *gethostbyname_internal(const char *, int, res_state); static const ns_src default_dns_files[] = { { NSSRC_FILES, NS_SUCCESS }, @@ -495,161 +490,40 @@ gethostbyname(const char *name) assert(name != NULL); - /* try IPv6 first - if that fails do IPv4 */ if (res->options & RES_USE_INET6) { - hp = gethostbyname_internal(name, AF_INET6, res, NULL); + hp = gethostbyname_internal(name, AF_INET6, res); if (hp) { __res_put_state(res); return hp; } } - hp = gethostbyname_internal(name, AF_INET, res, NULL); + hp = gethostbyname_internal(name, AF_INET, res); __res_put_state(res); return hp; } struct hostent * gethostbyname2(const char *name, int af) -{ - return android_gethostbynameforiface(name, af, NULL); -} - -struct hostent * -android_gethostbynameforiface(const char *name, int af, const char *iface) { struct hostent *hp; res_state res = __res_get_state(); if (res == NULL) return NULL; - hp = gethostbyname_internal(name, af, res, iface); + hp = gethostbyname_internal(name, af, res); __res_put_state(res); return hp; } -static struct hostent *gethostbyname_internal_real(const char *name, int af, res_state res); - -// very similar in proxy-ness to android_getaddrinfo_proxy static struct hostent * -gethostbyname_internal(const char *name, int af, res_state res, const char *iface) -{ - int sock; - const int one = 1; - struct sockaddr_un proxy_addr; - const char *cache_mode = getenv("ANDROID_DNS_MODE"); - FILE* proxy = NULL; - - if (cache_mode != NULL && strcmp(cache_mode, "local") == 0) { - res_setiface(res, iface); - return gethostbyname_internal_real(name, af, res); - } - - sock = socket(AF_UNIX, SOCK_STREAM, 0); - if (sock < 0) { - return NULL; - } - - setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)); - memset(&proxy_addr, 0, sizeof(proxy_addr)); - proxy_addr.sun_family = AF_UNIX; - strlcpy(proxy_addr.sun_path, "/dev/socket/dnsproxyd", sizeof(proxy_addr.sun_path)); - if (TEMP_FAILURE_RETRY(connect(sock, - (const struct sockaddr*) &proxy_addr, - sizeof(proxy_addr))) != 0) { - close(sock); - return NULL; - } - - proxy = fdopen(sock, "r+"); - /* This is writing to system/netd/DnsProxyListener.cpp and changes - * here need to be matched there */ - if (fprintf(proxy, "gethostbyname %d %s %d", - getpid(), - iface == NULL ? "^" : iface, - name == NULL ? "^" : name, - af) < 0) { - goto exit; - } - - if (fputc(0, proxy) == EOF || fflush(proxy) != 0) { - goto exit; - } - - uint32_t size; - char *buf = (char *)&size; - if (fread(buf, 1, sizeof(size), proxy) != 1) { - goto exit; - } - - /* This is reading serialized data from system/netd/DnsProxyListener.cpp - * and changes here need to be matched there */ - int result_code = (int)strtol(buf, NULL, 10); - if (result_code != DnsProxyQueryResult) goto exit; - - if (fread(buf, 1, sizeof(size), proxy) != 1) goto exit; - size = ntohl(size); - - res_static rs = __res_get_static(); - memset(&rs->host, 0, sizeof(rs->host)); - char *ptr = rs->hostbuf; - - if (fread(ptr, 1, size, proxy) != 1) goto exit; - ptr += size; - rs->host.h_name = rs->hostbuf; - - char **aliases = rs->host_aliases; - rs->host.h_aliases = rs->host_aliases; - while (1) { - if (fread(buf, 1, sizeof(size), proxy) != 1) goto exit; - size = ntohl(size); - if (fread(ptr, 1, size, proxy) != 1) goto exit; - if (size == 1) { - *aliases = NULL; - break; - } - *aliases++ = ptr; - ptr += size; - } - - if (fread(buf, 1, sizeof(size), proxy) != 1) goto exit; - rs->host.h_addrtype = ntohl(size); - - if (fread(buf, 1, sizeof(size), proxy) != 1) goto exit; - rs->host.h_length = ntohl(size); - - char **addrs = rs->h_addr_ptrs; - rs->host.h_addr_list = rs->h_addr_ptrs; - while (1) { - if (fread(buf, 1, sizeof(size), proxy) != 1) goto exit; - size = ntohl(size); - if (fread(ptr, 1, size, proxy) != 1) goto exit; - if (size == 1) { - *addrs = NULL; - break; - } - *addrs++ = ptr; - ptr += size; - } - - fclose(proxy); - return &rs->host; - -exit: - if (proxy != NULL) { - fclose(proxy); - } - return NULL; -} - - -static struct hostent * -gethostbyname_internal_real(const char *name, int af, res_state res) +gethostbyname_internal(const char *name, int af, res_state res) { const char *cp; char *bp, *ep; int size; struct hostent *hp; - res_static rs = __res_get_static(); + struct resolv_cache* cache; + res_static rs = __res_get_static(); static const ns_dtab dtab[] = { NS_FILES_CB(_gethtbyname, NULL) @@ -766,13 +640,6 @@ gethostbyname_internal_real(const char *name, int af, res_state res) struct hostent * gethostbyaddr(const void *addr, socklen_t len, int af) -{ - return android_gethostbyaddrforiface(addr, len, af, NULL); -} - -struct hostent * -android_gethostbyaddrforiface(const void *addr, - socklen_t len, int af, const char* iface) { const u_char *uaddr = (const u_char *)addr; socklen_t size; @@ -820,7 +687,7 @@ android_gethostbyaddrforiface(const void *addr, hp = NULL; h_errno = NETDB_INTERNAL; if (nsdispatch(&hp, dtab, NSDB_HOSTS, "gethostbyaddr", - default_dns_files, uaddr, len, af, iface) != NS_SUCCESS) + default_dns_files, uaddr, len, af) != NS_SUCCESS) return NULL; h_errno = NETDB_SUCCESS; return hp; @@ -1257,7 +1124,6 @@ _dns_gethtbyaddr(void *rv, void *cb_data, va_list ap) const unsigned char *uaddr; int len, af, advance; res_state res; - const char* iface; res_static rs = __res_get_static(); assert(rv != NULL); @@ -1265,7 +1131,6 @@ _dns_gethtbyaddr(void *rv, void *cb_data, va_list ap) uaddr = va_arg(ap, unsigned char *); len = va_arg(ap, int); af = va_arg(ap, int); - iface = va_arg(ap, char *); switch (af) { case AF_INET: @@ -1307,8 +1172,6 @@ _dns_gethtbyaddr(void *rv, void *cb_data, va_list ap) free(buf); return NS_NOTFOUND; } - res_setiface(res, iface); - _resolv_populate_res_for_iface(res); n = res_nquery(res, qbuf, C_IN, T_PTR, buf->buf, sizeof(buf->buf)); if (n < 0) { free(buf); diff --git a/libc/netbsd/net/getaddrinfo.c b/libc/netbsd/net/getaddrinfo.c index 4e23132ee..326b09c58 100644 --- a/libc/netbsd/net/getaddrinfo.c +++ b/libc/netbsd/net/getaddrinfo.c @@ -214,7 +214,7 @@ struct res_target { static int str2number(const char *); static int explore_fqdn(const struct addrinfo *, const char *, - const char *, struct addrinfo **, const char *iface); + const char *, struct addrinfo **); static int explore_null(const struct addrinfo *, const char *, struct addrinfo **); static int explore_numeric(const struct addrinfo *, const char *, @@ -402,15 +402,17 @@ _have_ipv4() { return _test_connect(PF_INET, &addr.generic, sizeof(addr.in)); } -// Returns 0 on success, else returns on error. +// Returns 0 on success, else returns non-zero on error (in which case +// getaddrinfo should continue as normal) static int android_getaddrinfo_proxy( const char *hostname, const char *servname, - const struct addrinfo *hints, struct addrinfo **res, const char *iface) + const struct addrinfo *hints, struct addrinfo **res) { int sock; const int one = 1; struct sockaddr_un proxy_addr; + const char* cache_mode = getenv("ANDROID_DNS_MODE"); FILE* proxy = NULL; int success = 0; @@ -419,17 +421,33 @@ android_getaddrinfo_proxy( // allocated in the process (before failing). *res = NULL; - // Bogus things we can't serialize. Don't use the proxy. These will fail - let them. + if (cache_mode != NULL && strcmp(cache_mode, "local") == 0) { + // Don't use the proxy in local mode. This is used by the + // proxy itself. + return -1; + } + + // Temporary cautious hack to disable the DNS proxy for processes + // requesting special treatment. Ideally the DNS proxy should + // accomodate these apps, though. + char propname[PROP_NAME_MAX]; + char propvalue[PROP_VALUE_MAX]; + snprintf(propname, sizeof(propname), "net.dns1.%d", getpid()); + if (__system_property_get(propname, propvalue) > 0) { + return -1; + } + + // Bogus things we can't serialize. Don't use the proxy. if ((hostname != NULL && strcspn(hostname, " \n\r\t^'\"") != strlen(hostname)) || (servname != NULL && strcspn(servname, " \n\r\t^'\"") != strlen(servname))) { - return EAI_NODATA; + return -1; } sock = socket(AF_UNIX, SOCK_STREAM, 0); if (sock < 0) { - return EAI_NODATA; + return -1; } setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)); @@ -441,20 +459,18 @@ android_getaddrinfo_proxy( (const struct sockaddr*) &proxy_addr, sizeof(proxy_addr))) != 0) { close(sock); - return EAI_NODATA; + return -1; } // Send the request. proxy = fdopen(sock, "r+"); - if (fprintf(proxy, "getaddrinfo %s %s %d %d %d %d %s %d", + if (fprintf(proxy, "getaddrinfo %s %s %d %d %d %d", hostname == NULL ? "^" : hostname, servname == NULL ? "^" : servname, hints == NULL ? -1 : hints->ai_flags, hints == NULL ? -1 : hints->ai_family, hints == NULL ? -1 : hints->ai_socktype, - hints == NULL ? -1 : hints->ai_protocol, - iface == NULL ? "^" : iface, - getpid()) < 0) { + hints == NULL ? -1 : hints->ai_protocol) < 0) { goto exit; } // literal NULL byte at end, required by FrameworkListener @@ -564,25 +580,19 @@ exit: return 0; } - // Proxy failed; - // clean up memory we might've allocated. + // Proxy failed; fall through to local + // resolver case. But first clean up any + // memory we might've allocated. if (*res) { freeaddrinfo(*res); *res = NULL; } - return EAI_NODATA; + return -1; } int getaddrinfo(const char *hostname, const char *servname, const struct addrinfo *hints, struct addrinfo **res) -{ - return android_getaddrinfoforiface(hostname, servname, hints, NULL, res); -} - -int -android_getaddrinfoforiface(const char *hostname, const char *servname, - const struct addrinfo *hints, const char *iface, struct addrinfo **res) { struct addrinfo sentinel; struct addrinfo *cur; @@ -591,12 +601,12 @@ android_getaddrinfoforiface(const char *hostname, const char *servname, struct addrinfo ai0; struct addrinfo *pai; const struct explore *ex; - const char* cache_mode = getenv("ANDROID_DNS_MODE"); /* hostname is allowed to be NULL */ /* servname is allowed to be NULL */ /* hints is allowed to be NULL */ assert(res != NULL); + memset(&sentinel, 0, sizeof(sentinel)); cur = &sentinel; pai = &ai; @@ -729,10 +739,9 @@ android_getaddrinfoforiface(const char *hostname, const char *servname, /* * BEGIN ANDROID CHANGES; proxying to the cache */ - if (cache_mode == NULL || strcmp(cache_mode, "local") != 0) { - // we're not the proxy - pass the request to them - return android_getaddrinfo_proxy(hostname, servname, hints, res, iface); - } + if (android_getaddrinfo_proxy(hostname, servname, hints, res) == 0) { + return 0; + } /* * hostname as alphabetical name. @@ -761,7 +770,7 @@ android_getaddrinfoforiface(const char *hostname, const char *servname, pai->ai_protocol = ex->e_protocol; error = explore_fqdn(pai, hostname, servname, - &cur->ai_next, iface); + &cur->ai_next); while (cur && cur->ai_next) cur = cur->ai_next; @@ -794,7 +803,7 @@ android_getaddrinfoforiface(const char *hostname, const char *servname, */ static int explore_fqdn(const struct addrinfo *pai, const char *hostname, - const char *servname, struct addrinfo **res, const char *iface) + const char *servname, struct addrinfo **res) { struct addrinfo *result; struct addrinfo *cur; @@ -820,7 +829,7 @@ explore_fqdn(const struct addrinfo *pai, const char *hostname, return 0; switch (nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo", - default_dns_files, hostname, pai, iface)) { + default_dns_files, hostname, pai)) { case NS_TRYAGAIN: error = EAI_AGAIN; goto free; @@ -1888,11 +1897,9 @@ _dns_getaddrinfo(void *rv, void *cb_data, va_list ap) struct addrinfo sentinel, *cur; struct res_target q, q2; res_state res; - const char* iface; name = va_arg(ap, char *); pai = va_arg(ap, const struct addrinfo *); - iface = va_arg(ap, char *); //fprintf(stderr, "_dns_getaddrinfo() name = '%s'\n", name); memset(&q, 0, sizeof(q)); @@ -1974,12 +1981,6 @@ _dns_getaddrinfo(void *rv, void *cb_data, va_list ap) return NS_NOTFOUND; } - /* this just sets our iface val in the thread private data so we don't have to - * modify the api's all the way down to res_send.c's res_nsend. We could - * fully populate the thread private data here, but if we get down there - * and have a cache hit that would be wasted, so we do the rest there on miss - */ - res_setiface(res, iface); if (res_searchN(name, &q, res) < 0) { __res_put_state(res); free(buf); diff --git a/libc/netbsd/net/getnameinfo.c b/libc/netbsd/net/getnameinfo.c index 7ab48e624..d8ac03743 100644 --- a/libc/netbsd/net/getnameinfo.c +++ b/libc/netbsd/net/getnameinfo.c @@ -99,7 +99,7 @@ struct sockinet { }; static int getnameinfo_inet __P((const struct sockaddr *, socklen_t, char *, - socklen_t, char *, socklen_t, int, const char*)); + socklen_t, char *, socklen_t, int)); #ifdef INET6 static int ip6_parsenumeric __P((const struct sockaddr *, const char *, char *, socklen_t, int)); @@ -121,34 +121,29 @@ static const int DnsProxyQueryResult = 222; * appropriate function to call. */ int getnameinfo(const struct sockaddr* sa, socklen_t salen, char* host, size_t hostlen, char* serv, size_t servlen, int flags) -{ - return android_getnameinfoforiface(sa, salen, host, hostlen, serv, servlen, flags, NULL); -} - -int android_getnameinfoforiface(const struct sockaddr* sa, socklen_t salen, char* host, size_t hostlen, char* serv, size_t servlen, int flags, const char* iface) { switch (sa->sa_family) { case AF_INET: case AF_INET6: return getnameinfo_inet(sa, salen, host, hostlen, - serv, servlen, flags, iface); + serv, servlen, flags); #if defined(ANDROID_CHANGES) && defined(AF_LINK) case AF_LINK: return getnameinfo_link(sa, salen, host, hostlen, - serv, servlen, flags); + serv, servlen, flags); #endif default: return EAI_FAMILY; } } + #ifdef ANDROID_CHANGES /* On success length of the host name is returned. A return * value of 0 means there's no host name associated with * the address. On failure -1 is returned in which case * normal execution flow shall continue. */ static int -android_gethostbyaddr_proxy(char* nameBuf, size_t nameBufLen, const void *addr, socklen_t addrLen, int addrFamily, const char* iface) -{ +android_gethostbyaddr_proxy(char* nameBuf, size_t nameBufLen, const void *addr, socklen_t addrLen, int addrFamily) { int sock; const int one = 1; @@ -163,6 +158,15 @@ android_gethostbyaddr_proxy(char* nameBuf, size_t nameBufLen, const void *addr, return -1; } + // Temporary cautious hack to disable the DNS proxy for processes + // requesting special treatment. Ideally the DNS proxy should + // accomodate these apps, though. + char propname[PROP_NAME_MAX]; + char propvalue[PROP_VALUE_MAX]; + snprintf(propname, sizeof(propname), "net.dns1.%d", getpid()); + if (__system_property_get(propname, propvalue) > 0) { + return -1; + } // create socket sock = socket(AF_UNIX, SOCK_STREAM, 0); if (sock < 0) { @@ -191,8 +195,7 @@ android_gethostbyaddr_proxy(char* nameBuf, size_t nameBufLen, const void *addr, if (addrStr == NULL) { goto exit; } - if (fprintf(proxy, "gethostbyaddr %s %d %d %d %s", - addrStr, addrLen, addrFamily, getpid(), iface == NULL ? "^" : iface) < 0) { + if (fprintf(proxy, "gethostbyaddr %s %d %d", addrStr, addrLen, addrFamily) < 0) { goto exit; } @@ -243,7 +246,7 @@ android_gethostbyaddr_proxy(char* nameBuf, size_t nameBufLen, const void *addr, * Format an IPv4 or IPv6 sockaddr into a printable string. */ static int -getnameinfo_inet(sa, salen, host, hostlen, serv, servlen, flags, iface) +getnameinfo_inet(sa, salen, host, hostlen, serv, servlen, flags) const struct sockaddr *sa; socklen_t salen; char *host; @@ -251,7 +254,6 @@ getnameinfo_inet(sa, salen, host, hostlen, serv, servlen, flags, iface) char *serv; socklen_t servlen; int flags; - const char* iface; { const struct afd *afd; struct servent *sp; @@ -396,14 +398,14 @@ getnameinfo_inet(sa, salen, host, hostlen, serv, servlen, flags, iface) char android_proxy_buf[MAXDNAME]; int hostnamelen = android_gethostbyaddr_proxy(android_proxy_buf, - MAXDNAME, addr, afd->a_addrlen, afd->a_af, iface); + MAXDNAME, addr, afd->a_addrlen, afd->a_af); if (hostnamelen > 0) { hp = &android_proxy_hostent; hp->h_name = android_proxy_buf; } else if (!hostnamelen) { hp = NULL; } else { - hp = android_gethostbyaddrforiface(addr, afd->a_addrlen, afd->a_af, iface); + hp = gethostbyaddr(addr, afd->a_addrlen, afd->a_af); } #else hp = gethostbyaddr(addr, afd->a_addrlen, afd->a_af); diff --git a/libc/netbsd/resolv/res_cache.c b/libc/netbsd/resolv/res_cache.c index 23f5c243d..afc9a365f 100644 --- a/libc/netbsd/resolv/res_cache.c +++ b/libc/netbsd/resolv/res_cache.c @@ -43,7 +43,6 @@ #include #include "resolv_private.h" #include "resolv_iface.h" -#include "res_private.h" /* This code implements a small and *simple* DNS resolver cache. * @@ -1250,16 +1249,9 @@ typedef struct resolv_cache_info { struct resolv_cache_info* next; char* nameservers[MAXNS +1]; struct addrinfo* nsaddrinfo[MAXNS + 1]; - char defdname[256]; - int dnsrch_offset[MAXDNSRCH+1]; // offsets into defdname + char* domains; } CacheInfo; -typedef struct resolv_pidiface_info { - int pid; - char ifname[IF_NAMESIZE + 1]; - struct resolv_pidiface_info* next; -} PidIfaceInfo; - #define HTABLE_VALID(x) ((x) != NULL && (x) != HTABLE_DELETED) static void @@ -1312,7 +1304,6 @@ _cache_check_pending_request_locked( struct resolv_cache* cache, Entry* key ) } } else { struct timespec ts = {0,0}; - XLOG("Waiting for previous request"); ts.tv_sec = _time_now() + PENDING_REQUEST_TIMEOUT; pthread_cond_timedwait(&ri->cond, &cache->lock, &ts); } @@ -1408,8 +1399,9 @@ _res_cache_get_max_entries( void ) if (cache_mode == NULL || strcmp(cache_mode, "local") != 0) { // Don't use the cache in local mode. This is used by the // proxy itself. - XLOG("setup cache for non-cache process. size=0, %s", cache_mode); - return 0; + // TODO - change this to 0 when all dns stuff uses proxy (5918973) + XLOG("setup cache for non-cache process. size=1"); + return 1; } if (__system_property_get(DNS_CACHE_SIZE_PROP_NAME, cache_size) > 0) { @@ -1548,7 +1540,7 @@ _cache_lookup_p( Cache* cache, pnode = &node->hlink; } - return pnode; + return pnode; } /* Add a new entry to the hash table. 'lookup' must be the @@ -1789,28 +1781,20 @@ Exit: /****************************************************************************/ /****************************************************************************/ -static pthread_once_t _res_cache_once = PTHREAD_ONCE_INIT; +static pthread_once_t _res_cache_once; // Head of the list of caches. Protected by _res_cache_list_lock. static struct resolv_cache_info _res_cache_list; -// List of pid iface pairs -static struct resolv_pidiface_info _res_pidiface_list; - // name of the current default inteface static char _res_default_ifname[IF_NAMESIZE + 1]; // lock protecting everything in the _resolve_cache_info structs (next ptr, etc) static pthread_mutex_t _res_cache_list_lock; -// lock protecting the _res_pid_iface_list -static pthread_mutex_t _res_pidiface_list_lock; /* lookup the default interface name */ static char *_get_default_iface_locked(); -/* find the first cache that has an associated interface and return the name of the interface */ -static char* _find_any_iface_name_locked( void ); - /* insert resolv_cache_info into the list of resolv_cache_infos */ static void _insert_cache_info_locked(struct resolv_cache_info* cache_info); /* creates a resolv_cache_info */ @@ -1831,14 +1815,8 @@ static int _get_nameserver_locked(const char* ifname, int n, char* addr, int add static struct addrinfo* _get_nameserver_addr_locked(const char* ifname, int n); /* lookup the inteface's address */ static struct in_addr* _get_addr_locked(const char * ifname); -/* return 1 if the provided list of name servers differs from the list of name servers - * currently attached to the provided cache_info */ -static int _resolv_is_nameservers_equal_locked(struct resolv_cache_info* cache_info, - char** servers, int numservers); -/* remove a resolv_pidiface_info structure from _res_pidiface_list */ -static void _remove_pidiface_info_locked(int pid); -/* get a resolv_pidiface_info structure from _res_pidiface_list with a certain pid */ -static struct resolv_pidiface_info* _get_pid_iface_info_locked(int pid); + + static void _res_cache_init(void) @@ -1852,36 +1830,37 @@ _res_cache_init(void) memset(&_res_default_ifname, 0, sizeof(_res_default_ifname)); memset(&_res_cache_list, 0, sizeof(_res_cache_list)); - memset(&_res_pidiface_list, 0, sizeof(_res_pidiface_list)); pthread_mutex_init(&_res_cache_list_lock, NULL); - pthread_mutex_init(&_res_pidiface_list_lock, NULL); } struct resolv_cache* -__get_res_cache(const char* ifname) +__get_res_cache(void) { struct resolv_cache *cache; pthread_once(&_res_cache_once, _res_cache_init); + pthread_mutex_lock(&_res_cache_list_lock); - char* iface; - if (ifname == NULL || ifname[0] == '\0') { - iface = _get_default_iface_locked(); - if (iface[0] == '\0') { - char* tmp = _find_any_iface_name_locked(); - if (tmp) { - iface = tmp; - } - } - } else { - iface = (char *) ifname; - } + char* ifname = _get_default_iface_locked(); - cache = _get_res_cache_for_iface_locked(iface); + // if default interface not set then use the first cache + // associated with an interface as the default one. + if (ifname[0] == '\0') { + struct resolv_cache_info* cache_info = _res_cache_list.next; + while (cache_info) { + if (cache_info->ifname[0] != '\0') { + ifname = cache_info->ifname; + break; + } + + cache_info = cache_info->next; + } + } + cache = _get_res_cache_for_iface_locked(ifname); pthread_mutex_unlock(&_res_cache_list_lock); - XLOG("_get_res_cache: iface = %s, cache=%p\n", iface, cache); + XLOG("_get_res_cache. default_ifname = %s\n", ifname); return cache; } @@ -2037,29 +2016,11 @@ _find_cache_info_locked(const char* ifname) static char* _get_default_iface_locked(void) { - char* iface = _res_default_ifname; return iface; } -static char* -_find_any_iface_name_locked( void ) { - char* ifname = NULL; - - struct resolv_cache_info* cache_info = _res_cache_list.next; - while (cache_info) { - if (cache_info->ifname[0] != '\0') { - ifname = cache_info->ifname; - break; - } - - cache_info = cache_info->next; - } - - return ifname; -} - void _resolv_set_default_iface(const char* ifname) { @@ -2083,19 +2044,16 @@ _resolv_set_nameservers_for_iface(const char* ifname, char** servers, int numser int i, rt, index; struct addrinfo hints; char sbuf[NI_MAXSERV]; - register char *cp; - int *offset; pthread_once(&_res_cache_once, _res_cache_init); - pthread_mutex_lock(&_res_cache_list_lock); + pthread_mutex_lock(&_res_cache_list_lock); // creates the cache if not created _get_res_cache_for_iface_locked(ifname); struct resolv_cache_info* cache_info = _find_cache_info_locked(ifname); - if (cache_info != NULL && - !_resolv_is_nameservers_equal_locked(cache_info, servers, numservers)) { + if (cache_info != NULL) { // free current before adding new _free_nameservers_locked(cache_info); @@ -2111,68 +2069,15 @@ _resolv_set_nameservers_for_iface(const char* ifname, char** servers, int numser if (rt == 0) { cache_info->nameservers[index] = strdup(servers[i]); index++; - XLOG("_resolv_set_nameservers_for_iface: iface = %s, addr = %s\n", - ifname, servers[i]); } else { cache_info->nsaddrinfo[index] = NULL; } } - - // code moved from res_init.c, load_domain_search_list - strlcpy(cache_info->defdname, domains, sizeof(cache_info->defdname)); - if ((cp = strchr(cache_info->defdname, '\n')) != NULL) - *cp = '\0'; - cp = cache_info->defdname; - offset = cache_info->dnsrch_offset; - while (offset < cache_info->dnsrch_offset + MAXDNSRCH) { - while (*cp == ' ' || *cp == '\t') /* skip leading white space */ - cp++; - if (*cp == '\0') /* stop if nothing more to do */ - break; - *offset++ = cp - cache_info->defdname; /* record this search domain */ - while (*cp) { /* zero-terminate it */ - if (*cp == ' '|| *cp == '\t') { - *cp++ = '\0'; - break; - } - cp++; - } - } - *offset = -1; /* cache_info->dnsrch_offset has MAXDNSRCH+1 items */ - - // flush cache since new settings - _flush_cache_for_iface_locked(ifname); - + cache_info->domains = strdup(domains); } - pthread_mutex_unlock(&_res_cache_list_lock); } -static int -_resolv_is_nameservers_equal_locked(struct resolv_cache_info* cache_info, - char** servers, int numservers) -{ - int i; - char** ns; - int equal = 1; - - // compare each name server against current name servers - if (numservers > MAXNS) numservers = MAXNS; - for (i = 0; i < numservers && equal; i++) { - ns = cache_info->nameservers; - equal = 0; - while(*ns) { - if (strcmp(*ns, servers[i]) == 0) { - equal = 1; - break; - } - ns++; - } - } - - return equal; -} - static void _free_nameservers_locked(struct resolv_cache_info* cache_info) { @@ -2315,192 +2220,3 @@ _get_addr_locked(const char * ifname) } return NULL; } - -static void -_remove_pidiface_info_locked(int pid) { - struct resolv_pidiface_info* result = &_res_pidiface_list; - struct resolv_pidiface_info* prev = NULL; - - while (result != NULL && result->pid != pid) { - prev = result; - result = result->next; - } - if (prev != NULL && result != NULL) { - prev->next = result->next; - free(result); - } -} - -static struct resolv_pidiface_info* -_get_pid_iface_info_locked(int pid) -{ - struct resolv_pidiface_info* result = &_res_pidiface_list; - while (result != NULL && result->pid != pid) { - result = result->next; - } - - return result; -} - -void -_resolv_set_iface_for_pid(const char* ifname, int pid) -{ - // make sure the pid iface list is created - pthread_once(&_res_cache_once, _res_cache_init); - pthread_mutex_lock(&_res_pidiface_list_lock); - - struct resolv_pidiface_info* pidiface_info = _get_pid_iface_info_locked(pid); - if (!pidiface_info) { - pidiface_info = calloc(sizeof(*pidiface_info), 1); - if (pidiface_info) { - pidiface_info->pid = pid; - int len = sizeof(pidiface_info->ifname); - strncpy(pidiface_info->ifname, ifname, len - 1); - pidiface_info->ifname[len - 1] = '\0'; - - pidiface_info->next = _res_pidiface_list.next; - _res_pidiface_list.next = pidiface_info; - - XLOG("_resolv_set_iface_for_pid: pid %d , iface %s\n", pid, ifname); - } else { - XLOG("_resolv_set_iface_for_pid failing calloc"); - } - } - - pthread_mutex_unlock(&_res_pidiface_list_lock); -} - -void -_resolv_clear_iface_for_pid(int pid) -{ - pthread_once(&_res_cache_once, _res_cache_init); - pthread_mutex_lock(&_res_pidiface_list_lock); - - _remove_pidiface_info_locked(pid); - - XLOG("_resolv_clear_iface_for_pid: pid %d\n", pid); - - pthread_mutex_unlock(&_res_pidiface_list_lock); -} - -int -_resolv_get_pids_associated_interface(int pid, char* buff, int buffLen) -{ - int len = 0; - - if (!buff) { - return -1; - } - - pthread_once(&_res_cache_once, _res_cache_init); - pthread_mutex_lock(&_res_pidiface_list_lock); - - struct resolv_pidiface_info* pidiface_info = _get_pid_iface_info_locked(pid); - buff[0] = '\0'; - if (pidiface_info) { - len = strlen(pidiface_info->ifname); - if (len < buffLen) { - strncpy(buff, pidiface_info->ifname, len); - buff[len] = '\0'; - } - } - - XLOG("_resolv_get_pids_associated_interface buff: %s\n", buff); - - pthread_mutex_unlock(&_res_pidiface_list_lock); - - return len; -} - -int -_resolv_get_default_iface(char* buff, int buffLen) -{ - char* ifname; - int len = 0; - - if (!buff || buffLen == 0) { - return -1; - } - - pthread_once(&_res_cache_once, _res_cache_init); - pthread_mutex_lock(&_res_cache_list_lock); - - ifname = _get_default_iface_locked(); - - // if default interface not set. Get first cache with an interface - if (ifname[0] == '\0') { - ifname = _find_any_iface_name_locked(); - } - - if (ifname) { - len = strlen(ifname); - if (len < buffLen) { - strncpy(buff, ifname, len); - buff[len] = '\0'; - } - } else { - buff[0] = '\0'; - } - - pthread_mutex_unlock(&_res_cache_list_lock); - - return len; -} - -int -_resolv_populate_res_for_iface(res_state statp) -{ - int nserv; - struct resolv_cache_info* info = NULL; - - if (statp) { - struct addrinfo* ai; - - if (statp->iface[0] == '\0') { // no interface set assign default - _resolv_get_default_iface(statp->iface, sizeof(statp->iface)); - } - - pthread_once(&_res_cache_once, _res_cache_init); - pthread_mutex_lock(&_res_cache_list_lock); - info = _find_cache_info_locked(statp->iface); - - if (info == NULL) return 0; - - XLOG("_resolv_populate_res_for_iface: %s\n", statp->iface); - for (nserv = 0; nserv < MAXNS; nserv++) { - ai = info->nsaddrinfo[nserv]; - if (ai == NULL) { - break; - } - - if ((size_t) ai->ai_addrlen <= sizeof(statp->_u._ext.ext->nsaddrs[0])) { - if (statp->_u._ext.ext != NULL) { - memcpy(&statp->_u._ext.ext->nsaddrs[nserv], ai->ai_addr, ai->ai_addrlen); - statp->nsaddr_list[nserv].sin_family = AF_UNSPEC; - } else { - if ((size_t) ai->ai_addrlen - <= sizeof(statp->nsaddr_list[0])) { - memcpy(&statp->nsaddr_list[nserv], ai->ai_addr, - ai->ai_addrlen); - } else { - statp->nsaddr_list[nserv].sin_family = AF_UNSPEC; - } - } - } else { - XLOG("_resolv_populate_res_for_iface found too long addrlen"); - } - } - statp->nscount = nserv; - // now do search domains. Note that we cache the offsets as this code runs alot - // but the setting/offset-computer only runs when set/changed - strlcpy(statp->defdname, info->defdname, sizeof(statp->defdname)); - register char **pp = statp->dnsrch; - register int *p = info->dnsrch_offset; - while (pp < statp->dnsrch + MAXDNSRCH && *p != -1) { - *pp++ = &statp->defdname + *p++; - } - - pthread_mutex_unlock(&_res_cache_list_lock); - } - return nserv; -} diff --git a/libc/netbsd/resolv/res_data.c b/libc/netbsd/resolv/res_data.c index 7e5a30849..014c99bf0 100644 --- a/libc/netbsd/resolv/res_data.c +++ b/libc/netbsd/resolv/res_data.c @@ -82,7 +82,13 @@ extern struct __res_state _nres; int res_ourserver_p(const res_state, const struct sockaddr *); +#ifdef ANDROID_CHANGES +static int res_need_init() { + return ((_nres.options & RES_INIT) == 0U) || res_get_dns_changed(); +} +#else #define res_need_init() ((_nres.options & RES_INIT) == 0U) +#endif int res_init(void) { diff --git a/libc/netbsd/resolv/res_init.c b/libc/netbsd/resolv/res_init.c index ff6529944..56a25afb8 100644 --- a/libc/netbsd/resolv/res_init.c +++ b/libc/netbsd/resolv/res_init.c @@ -111,6 +111,13 @@ __RCSID("$NetBSD: res_init.c,v 1.8 2006/03/19 03:10:08 christos Exp $"); /* ensure that sockaddr_in6 and IN6ADDR_ANY_INIT are declared / defined */ #ifdef ANDROID_CHANGES #include "resolv_private.h" +#define MAX_DNS_PROPERTIES 8 +#define DNS_PROP_NAME_PREFIX "net.dns" +#define DNS_CHANGE_PROP_NAME "net.dnschange" +#define DNS_SEARCH_PROP_NAME "net.dns.search" +static const prop_info *dns_change_prop; +static int dns_last_change_counter; +static int _get_dns_change_count(); #else #include #endif @@ -164,6 +171,41 @@ res_ninit(res_state statp) { return (__res_vinit(statp, 0)); } +#ifdef ANDROID_CHANGES +static int load_domain_search_list(res_state statp) { + char propvalue[PROP_VALUE_MAX]; + register char *cp, **pp; + + if(__system_property_get(DNS_SEARCH_PROP_NAME, propvalue) >= 1) { + strlcpy(statp->defdname, propvalue, sizeof(statp->defdname)); + if ((cp = strchr(statp->defdname, '\n')) != NULL) + *cp = '\0'; + cp = statp->defdname; + pp = statp->dnsrch; + while ( pp < statp->dnsrch + MAXDNSRCH ) { + while (*cp == ' ' || *cp == '\t') /* skip leading white space */ + cp++; + if (*cp == '\0') /* stop if nothing more */ + break; + *pp++ = cp; /* record this search domain */ + while (*cp) { /* zero-terminate it */ + if (*cp == ' ' || *cp == '\t') { + *cp++ = '\0'; + break; + } + cp++; + } + } + *pp = NULL; /* statp->dnsrch has MAXDNSRCH+1 items */ + if (pp > statp->dnsrch) + return 1; + } + statp->defdname[0] = '\0'; /* no default domain name on Android */ + statp->dnsrch[0] = NULL; + return 0; +} +#endif + /* This function has to be reachable by res_data.c but not publicly. */ int __res_vinit(res_state statp, int preinit) { @@ -178,6 +220,12 @@ __res_vinit(res_state statp, int preinit) { char *net; int dots; union res_sockaddr_union u[2]; +#ifdef ANDROID_CHANGES + pid_t mypid = getpid(); + int use_proc_props = 0; + int found_prop; + char dnsProperty[PROP_VALUE_MAX]; +#endif if ((statp->options & RES_INIT) != 0U) res_ndestroy(statp); @@ -270,8 +318,74 @@ __res_vinit(res_state statp, int preinit) { if (nserv > 0) statp->nscount = nserv; #endif +#ifdef ANDROID_CHANGES /* READ FROM SYSTEM PROPERTIES */ + dns_last_change_counter = _get_dns_change_count(); -#ifndef ANDROID_CHANGES /* !ANDROID_CHANGES - IGNORE resolv.conf in Android */ + nserv = 0; + for(n = 1; n <= MAX_DNS_PROPERTIES && nserv < MAXNS; n++) { + char propname[PROP_NAME_MAX]; + char propvalue[PROP_VALUE_MAX]; + + struct addrinfo hints, *ai; + char sbuf[NI_MAXSERV]; + const size_t minsiz = sizeof(statp->_u._ext.ext->nsaddrs[0]); + + /* + * Check first for process-specific properties, and if those don't + * exist, try the generic properties. + */ + found_prop = 0; + if (n == 1 || use_proc_props) { + snprintf(propname, sizeof(propname), "%s%d.%d", DNS_PROP_NAME_PREFIX, n, mypid); + if(__system_property_get(propname, propvalue) < 1) { + if (use_proc_props) { + break; + } + } else { + found_prop = 1; + use_proc_props = 1; + } + } + if (!found_prop) { + snprintf(propname, sizeof(propname), "%s%d", DNS_PROP_NAME_PREFIX, n); + if(__system_property_get(propname, propvalue) < 1) { + break; + } + } + + cp = propvalue; + + while (*cp == ' ' || *cp == '\t') + cp++; + cp[strcspn(cp, ";# \t\n")] = '\0'; + if ((*cp != '\0') && (*cp != '\n')) { + memset(&hints, 0, sizeof(hints)); + hints.ai_family = PF_UNSPEC; + hints.ai_socktype = SOCK_DGRAM; /*dummy*/ + hints.ai_flags = AI_NUMERICHOST; + sprintf(sbuf, "%u", NAMESERVER_PORT); + if (getaddrinfo(cp, sbuf, &hints, &ai) == 0 && + (size_t)ai->ai_addrlen <= minsiz) { + if (statp->_u._ext.ext != NULL) { + memcpy(&statp->_u._ext.ext->nsaddrs[nserv], + ai->ai_addr, ai->ai_addrlen); + } + if ((size_t)ai->ai_addrlen <= + sizeof(statp->nsaddr_list[nserv])) { + memcpy(&statp->nsaddr_list[nserv], + ai->ai_addr, ai->ai_addrlen); + } else { + statp->nsaddr_list[nserv].sin_family = 0; + } + freeaddrinfo(ai); + nserv++; + } + } + } + + /* Add the domain search list */ + havesearch = load_domain_search_list(statp); +#else /* !ANDROID_CHANGES - IGNORE resolv.conf in Android */ #define MATCH(line, name) \ (!strncmp(line, name, sizeof(name) - 1) && \ (line[sizeof(name) - 1] == ' ' || \ @@ -793,17 +907,32 @@ res_getservers(res_state statp, union res_sockaddr_union *set, int cnt) { } #ifdef ANDROID_CHANGES -void res_setiface(res_state statp, const char* iface) +static int _get_dns_change_count() { - if (statp != NULL) { - // set interface - if (iface && iface[0] != '\0') { - int len = sizeof(statp->iface); - strncpy(statp->iface, iface, len - 1); - statp->iface[len - 1] = '\0'; - } else { - statp->iface[0] = '\0'; + if (dns_change_prop == NULL) { + dns_change_prop = __system_property_find(DNS_CHANGE_PROP_NAME); + } + if (dns_change_prop != NULL) { + char propvalue[PROP_VALUE_MAX]; + if (__system_property_read(dns_change_prop, NULL, propvalue) >= 1) { + return atoi(propvalue); } } + return -1; +} + +int res_get_dns_changed() +{ + int change_count; + + change_count = _get_dns_change_count(); + if (change_count != dns_last_change_counter) { + if (change_count != -1) { + dns_last_change_counter = change_count; + } + return 1; + } else { + return 0; + } } #endif /* ANDROID_CHANGES */ diff --git a/libc/netbsd/resolv/res_send.c b/libc/netbsd/resolv/res_send.c index 0be6e8ef7..f3ee53979 100644 --- a/libc/netbsd/resolv/res_send.c +++ b/libc/netbsd/resolv/res_send.c @@ -370,13 +370,10 @@ res_nsend(res_state statp, ResolvCacheStatus cache_status = RESOLV_CACHE_UNSUPPORTED; #endif -#if !USE_RESOLV_CACHE if (statp->nscount == 0) { errno = ESRCH; return (-1); } -#endif - if (anssiz < HFIXEDSZ) { errno = EINVAL; return (-1); @@ -388,8 +385,7 @@ res_nsend(res_state statp, terrno = ETIMEDOUT; #if USE_RESOLV_CACHE - // get the cache associated with the interface - cache = __get_res_cache(statp->iface); + cache = __get_res_cache(); if (cache != NULL) { int anslen = 0; cache_status = _resolv_cache_lookup( @@ -398,17 +394,8 @@ res_nsend(res_state statp, if (cache_status == RESOLV_CACHE_FOUND) { return anslen; - } else { - // had a cache miss for a known interface, so populate the thread private - // data so the normal resolve path can do its thing - _resolv_populate_res_for_iface(statp); } } - - if (statp->nscount == 0) { - errno = ESRCH; - return (-1); - } #endif /* diff --git a/libc/netbsd/resolv/res_state.c b/libc/netbsd/resolv/res_state.c index efaa519a1..e05846a93 100644 --- a/libc/netbsd/resolv/res_state.c +++ b/libc/netbsd/resolv/res_state.c @@ -50,7 +50,7 @@ #endif static pthread_key_t _res_key; -static pthread_once_t _res_once = PTHREAD_ONCE_INIT; +static pthread_once_t _res_once; typedef struct { int _h_errno; diff --git a/libc/private/resolv_cache.h b/libc/private/resolv_cache.h index 4f32fb75f..1dcc53fa1 100644 --- a/libc/private/resolv_cache.h +++ b/libc/private/resolv_cache.h @@ -28,13 +28,13 @@ #ifndef _RESOLV_CACHE_H_ #define _RESOLV_CACHE_H_ -struct __res_state; struct resolv_cache; /* forward */ -/* gets the cache for an interface. Set ifname argument to NULL or - * empty buffer ('\0') to get cache for default interface. - * returned cache might be NULL*/ -extern struct resolv_cache* __get_res_cache(const char* ifname); +/* gets the cache for the default interface. Might be NULL*/ +extern struct resolv_cache* __get_res_cache(void); + +/* get the cache for a specified interface. Can be NULL*/ +extern struct resolv_cache* __get_res_cache_for_iface(const char* ifname); /* this gets called everytime we detect some changes in the DNS configuration * and will flush the cache */ @@ -67,14 +67,8 @@ extern struct in_addr* _resolv_get_addr_of_default_iface(); /* gets the address associated with the specified interface */ extern struct in_addr* _resolv_get_addr_of_iface(const char* ifname); -/* Copy the name of the default interface to provided buffer. - * Return length of buffer on success on failure -1 is returned */ -extern int _resolv_get_default_iface(char* buff, int buffLen); - -/* sets the name server addresses to the provided res_state structure. The - * name servers are retrieved from the cache which is associated - * with the interface to which the res_state structure is associated */ -extern int _resolv_populate_res_for_iface(struct __res_state* statp); +/* Get name of default interface */ +extern char* _resolv_get_default_iface(); typedef enum { RESOLV_CACHE_UNSUPPORTED, /* the cache can't handle that kind of queries */ diff --git a/libc/private/resolv_iface.h b/libc/private/resolv_iface.h index bf5abad7d..3fe586ec0 100644 --- a/libc/private/resolv_iface.h +++ b/libc/private/resolv_iface.h @@ -60,21 +60,6 @@ extern void _resolv_flush_cache_for_default_iface(); /* flush the cache associated with a certain interface */ extern void _resolv_flush_cache_for_iface(const char* ifname); -/* set a pid to use the name servers of the specified interface */ -extern void _resolv_set_iface_for_pid(const char* ifname, int pid); - -/* clear pid from being associated with an interface */ -extern void _resolv_clear_iface_for_pid(int pid); - -/** Gets the name of the interface to which the pid is attached. - * On error, -1 is returned. - * If no interface is found, 0 is returned and buff is set to empty ('\0'). - * If an interface is found, the name is copied to buff and the length of the name is returned. - * Arguments: pid The pid to find an interface for - * buff A buffer to copy the result to - * buffLen Length of buff. An interface is at most IF_NAMESIZE in length */ -extern int _resolv_get_pids_associated_interface(int pid, char* buff, int buffLen); - #endif /* _BIONIC_RESOLV_IFACE_FUNCTIONS_DECLARED */ __END_DECLS diff --git a/libc/private/resolv_private.h b/libc/private/resolv_private.h index 1c3c1a28c..0f3c6c04e 100644 --- a/libc/private/resolv_private.h +++ b/libc/private/resolv_private.h @@ -56,7 +56,6 @@ #include #include "resolv_static.h" -#include /* * Revision information. This is the release date in YYYYMMDD format. @@ -140,7 +139,6 @@ struct res_sym { struct __res_state_ext; struct __res_state { - char iface[IF_NAMESIZE+1]; int retrans; /* retransmission time interval */ int retry; /* number of times to retransmit */ #ifdef sun @@ -493,7 +491,7 @@ void res_setservers(res_state, int res_getservers(res_state, union res_sockaddr_union *, int); -void res_setiface(); +int res_get_dns_changed(); u_int res_randomid(void); __END_DECLS