/* * Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ #include #include #include #include #include #include #include #include #include #include #include #include #include "jvm.h" #include "jni_util.h" #include "net_util.h" #include "java_net_Inet4AddressImpl.h" /* the initial size of our hostent buffers */ #define HENT_BUF_SIZE 1024 #define BIG_HENT_BUF_SIZE 10240 /* a jumbo-sized one */ /************************************************************************ * Inet4AddressImpl */ /* * Class: java_net_Inet4AddressImpl * Method: getLocalHostName * Signature: ()Ljava/lang/String; */ JNIEXPORT jstring JNICALL Java_java_net_Inet4AddressImpl_getLocalHostName(JNIEnv *env, jobject this) { char hostname[MAXHOSTNAMELEN+1]; hostname[0] = '\0'; if (JVM_GetHostName(hostname, MAXHOSTNAMELEN)) { /* Something went wrong, maybe networking is not setup? */ strcpy(hostname, "localhost"); } else { #ifdef __linux__ /* On Linux gethostname() says "host.domain.sun.com". On * Solaris gethostname() says "host", so extra work is needed. */ #else /* Solaris doesn't want to give us a fully qualified domain name. * We do a reverse lookup to try and get one. This works * if DNS occurs before NIS in /etc/resolv.conf, but fails * if NIS comes first (it still gets only a partial name). * We use thread-safe system calls. */ #endif /* __linux__ */ struct hostent res, res2, *hp; char buf[HENT_BUF_SIZE]; char buf2[HENT_BUF_SIZE]; int h_error=0; #ifdef __GLIBC__ gethostbyname_r(hostname, &res, buf, sizeof(buf), &hp, &h_error); #else hp = gethostbyname_r(hostname, &res, buf, sizeof(buf), &h_error); #endif if (hp) { #ifdef __GLIBC__ gethostbyaddr_r(hp->h_addr, hp->h_length, AF_INET, &res2, buf2, sizeof(buf2), &hp, &h_error); #else hp = gethostbyaddr_r(hp->h_addr, hp->h_length, AF_INET, &res2, buf2, sizeof(buf2), &h_error); #endif if (hp) { /* * If gethostbyaddr_r() found a fully qualified host name, * returns that name. Otherwise, returns the hostname * found by gethostname(). */ char *p = hp->h_name; if ((strlen(hp->h_name) > strlen(hostname)) && (strncmp(hostname, hp->h_name, strlen(hostname)) == 0) && (*(p + strlen(hostname)) == '.')) strcpy(hostname, hp->h_name); } } } return (*env)->NewStringUTF(env, hostname); } static jclass ni_iacls; static jclass ni_ia4cls; static jmethodID ni_ia4ctrID; static jfieldID ni_iaaddressID; static jfieldID ni_iahostID; static jfieldID ni_iafamilyID; static int initialized = 0; /* * Find an internet address for a given hostname. Note that this * code only works for addresses of type INET. The translation * of %d.%d.%d.%d to an address (int) occurs in java now, so the * String "host" shouldn't *ever* be a %d.%d.%d.%d string * * Class: java_net_Inet4AddressImpl * Method: lookupAllHostAddr * Signature: (Ljava/lang/String;)[[B */ JNIEXPORT jobjectArray JNICALL Java_java_net_Inet4AddressImpl_lookupAllHostAddr(JNIEnv *env, jobject this, jstring host) { const char *hostname; jobjectArray ret = 0; struct hostent res, *hp = 0; char buf[HENT_BUF_SIZE]; /* temporary buffer, on the off chance we need to expand */ char *tmp = NULL; int h_error=0; if (!initialized) { ni_iacls = (*env)->FindClass(env, "java/net/InetAddress"); ni_iacls = (*env)->NewGlobalRef(env, ni_iacls); ni_ia4cls = (*env)->FindClass(env, "java/net/Inet4Address"); ni_ia4cls = (*env)->NewGlobalRef(env, ni_ia4cls); ni_ia4ctrID = (*env)->GetMethodID(env, ni_ia4cls, "", "()V"); ni_iaaddressID = (*env)->GetFieldID(env, ni_iacls, "address", "I"); ni_iafamilyID = (*env)->GetFieldID(env, ni_iacls, "family", "I"); ni_iahostID = (*env)->GetFieldID(env, ni_iacls, "hostName", "Ljava/lang/String;"); initialized = 1; } if (IS_NULL(host)) { JNU_ThrowNullPointerException(env, "host is null"); return 0; } hostname = JNU_GetStringPlatformChars(env, host, JNI_FALSE); CHECK_NULL_RETURN(hostname, NULL); #ifdef __solaris__ /* * Workaround for Solaris bug 4160367 - if a hostname contains a * white space then 0.0.0.0 is returned */ if (isspace((unsigned char)hostname[0])) { JNU_ThrowByName(env, JNU_JAVANETPKG "UnknownHostException", (char *)hostname); JNU_ReleaseStringPlatformChars(env, host, hostname); return NULL; } #endif /* Try once, with our static buffer. */ #ifdef __GLIBC__ gethostbyname_r(hostname, &res, buf, sizeof(buf), &hp, &h_error); #else hp = gethostbyname_r(hostname, &res, buf, sizeof(buf), &h_error); #endif /* With the re-entrant system calls, it's possible that the buffer * we pass to it is not large enough to hold an exceptionally * large DNS entry. This is signaled by errno->ERANGE. We try once * more, with a very big size. */ if (hp == NULL && errno == ERANGE) { if ((tmp = (char*)malloc(BIG_HENT_BUF_SIZE))) { #ifdef __GLIBC__ gethostbyname_r(hostname, &res, tmp, BIG_HENT_BUF_SIZE, &hp, &h_error); #else hp = gethostbyname_r(hostname, &res, tmp, BIG_HENT_BUF_SIZE, &h_error); #endif } } if (hp != NULL) { struct in_addr **addrp = (struct in_addr **) hp->h_addr_list; int i = 0; while (*addrp != (struct in_addr *) 0) { i++; addrp++; } ret = (*env)->NewObjectArray(env, i, ni_iacls, NULL); if (IS_NULL(ret)) { /* we may have memory to free at the end of this */ goto cleanupAndReturn; } addrp = (struct in_addr **) hp->h_addr_list; i = 0; while (*addrp) { jobject iaObj = (*env)->NewObject(env, ni_ia4cls, ni_ia4ctrID); if (IS_NULL(iaObj)) { ret = NULL; goto cleanupAndReturn; } (*env)->SetIntField(env, iaObj, ni_iaaddressID, ntohl((*addrp)->s_addr)); (*env)->SetObjectField(env, iaObj, ni_iahostID, host); (*env)->SetObjectArrayElement(env, ret, i, iaObj); addrp++; i++; } } else { JNU_ThrowByName(env, JNU_JAVANETPKG "UnknownHostException", (char *)hostname); ret = NULL; } cleanupAndReturn: JNU_ReleaseStringPlatformChars(env, host, hostname); if (tmp != NULL) { free(tmp); } return ret; } /* * Class: java_net_Inet4AddressImpl * Method: getHostByAddr * Signature: (I)Ljava/lang/String; */ JNIEXPORT jstring JNICALL Java_java_net_Inet4AddressImpl_getHostByAddr(JNIEnv *env, jobject this, jbyteArray addrArray) { jstring ret = NULL; jint addr; struct hostent hent, *hp = 0; char buf[HENT_BUF_SIZE]; int h_error = 0; char *tmp = NULL; /* * We are careful here to use the reentrant version of * gethostbyname because at the Java level this routine is not * protected by any synchronization. * * Still keeping the reentrant platform dependent calls temporarily * We should probably conform to one interface later. * */ jbyte caddr[4]; (*env)->GetByteArrayRegion(env, addrArray, 0, 4, caddr); addr = ((caddr[0]<<24) & 0xff000000); addr |= ((caddr[1] <<16) & 0xff0000); addr |= ((caddr[2] <<8) & 0xff00); addr |= (caddr[3] & 0xff); addr = htonl(addr); #ifdef __GLIBC__ gethostbyaddr_r((char *)&addr, sizeof(addr), AF_INET, &hent, buf, sizeof(buf), &hp, &h_error); #else hp = gethostbyaddr_r((char *)&addr, sizeof(addr), AF_INET, &hent, buf, sizeof(buf), &h_error); #endif /* With the re-entrant system calls, it's possible that the buffer * we pass to it is not large enough to hold an exceptionally * large DNS entry. This is signaled by errno->ERANGE. We try once * more, with a very big size. */ if (hp == NULL && errno == ERANGE) { if ((tmp = (char*)malloc(BIG_HENT_BUF_SIZE))) { #ifdef __GLIBC__ gethostbyaddr_r((char *)&addr, sizeof(addr), AF_INET, &hent, tmp, BIG_HENT_BUF_SIZE, &hp, &h_error); #else hp = gethostbyaddr_r((char *)&addr, sizeof(addr), AF_INET, &hent, tmp, BIG_HENT_BUF_SIZE, &h_error); #endif } else { JNU_ThrowOutOfMemoryError(env, "getHostByAddr"); } } if (hp == NULL) { JNU_ThrowByName(env, JNU_JAVANETPKG "UnknownHostException", NULL); } else { ret = (*env)->NewStringUTF(env, hp->h_name); } if (tmp) { free(tmp); } return ret; } #define SET_NONBLOCKING(fd) { \ int flags = fcntl(fd, F_GETFL); \ flags |= O_NONBLOCK; \ fcntl(fd, F_SETFL, flags); \ } /** * ping implementation. * Send a ICMP_ECHO_REQUEST packet every second until either the timeout * expires or a answer is received. * Returns true is an ECHO_REPLY is received, otherwise, false. */ static jboolean ping4(JNIEnv *env, jint fd, struct sockaddr_in* him, jint timeout, struct sockaddr_in* netif, jint ttl) { jint size; jint n, hlen1, icmplen; socklen_t len; char sendbuf[1500]; char recvbuf[1500]; struct icmp *icmp; struct ip *ip; struct sockaddr_in sa_recv; jchar pid; jint tmout2, seq = 1; struct timeval tv; size_t plen; /* icmp_id is a 16 bit data type, therefore down cast the pid */ pid = (jchar)getpid(); size = 60*1024; setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &size, sizeof(size)); /* * sets the ttl (max number of hops) */ if (ttl > 0) { setsockopt(fd, IPPROTO_IP, IP_TTL, &ttl, sizeof(ttl)); } /* * a specific interface was specified, so let's bind the socket * to that interface to ensure the requests are sent only through it. */ if (netif != NULL) { if (bind(fd, (struct sockaddr*)netif, sizeof(struct sockaddr_in)) < 0) { NET_ThrowNew(env, errno, "Can't bind socket"); close(fd); return JNI_FALSE; } } /* * Make the socket non blocking so we can use select */ SET_NONBLOCKING(fd); do { /* * create the ICMP request */ icmp = (struct icmp *) sendbuf; icmp->icmp_type = ICMP_ECHO; icmp->icmp_code = 0; icmp->icmp_id = htons(pid); icmp->icmp_seq = htons(seq); seq++; gettimeofday(&tv, NULL); memcpy(icmp->icmp_data, &tv, sizeof(tv)); plen = ICMP_ADVLENMIN + sizeof(tv); icmp->icmp_cksum = 0; icmp->icmp_cksum = in_cksum((u_short *)icmp, plen); /* * send it */ n = sendto(fd, sendbuf, plen, 0, (struct sockaddr *)him, sizeof(struct sockaddr)); if (n < 0 && errno != EINPROGRESS ) { #ifdef __linux__ if (errno != EINVAL) /* * On some Linuxes, when bound to the loopback interface, sendto * will fail and errno will be set to EINVAL. When that happens, * don't throw an exception, just return false. */ #endif /*__linux__ */ NET_ThrowNew(env, errno, "Can't send ICMP packet"); close(fd); return JNI_FALSE; } tmout2 = timeout > 1000 ? 1000 : timeout; do { tmout2 = NET_Wait(env, fd, NET_WAIT_READ, tmout2); if (tmout2 >= 0) { len = sizeof(sa_recv); n = recvfrom(fd, recvbuf, sizeof(recvbuf), 0, (struct sockaddr *)&sa_recv, &len); ip = (struct ip*) recvbuf; hlen1 = (ip->ip_hl) << 2; icmp = (struct icmp *) (recvbuf + hlen1); icmplen = n - hlen1; /* * We did receive something, but is it what we were expecting? * I.E.: A ICMP_ECHOREPLY packet with the proper PID. */ if (icmplen >= 8 && icmp->icmp_type == ICMP_ECHOREPLY && (ntohs(icmp->icmp_id) == pid) && (him->sin_addr.s_addr == sa_recv.sin_addr.s_addr)) { close(fd); return JNI_TRUE; } } } while (tmout2 > 0); timeout -= 1000; } while (timeout >0); close(fd); return JNI_FALSE; } /* * Class: java_net_Inet4AddressImpl * Method: isReachable0 * Signature: ([bI[bI)Z */ JNIEXPORT jboolean JNICALL Java_java_net_Inet4AddressImpl_isReachable0(JNIEnv *env, jobject this, jbyteArray addrArray, jint timeout, jbyteArray ifArray, jint ttl) { jint addr; jbyte caddr[4]; jint fd; struct sockaddr_in him; struct sockaddr_in* netif = NULL; struct sockaddr_in inf; int len = 0; int connect_rv = -1; int sz; memset((char *) caddr, 0, sizeof(caddr)); memset((char *) &him, 0, sizeof(him)); sz = (*env)->GetArrayLength(env, addrArray); if (sz != 4) { return JNI_FALSE; } (*env)->GetByteArrayRegion(env, addrArray, 0, 4, caddr); addr = ((caddr[0]<<24) & 0xff000000); addr |= ((caddr[1] <<16) & 0xff0000); addr |= ((caddr[2] <<8) & 0xff00); addr |= (caddr[3] & 0xff); addr = htonl(addr); him.sin_addr.s_addr = addr; him.sin_family = AF_INET; len = sizeof(him); /* * If a network interface was specified, let's create the address * for it. */ if (!(IS_NULL(ifArray))) { memset((char *) caddr, 0, sizeof(caddr)); (*env)->GetByteArrayRegion(env, ifArray, 0, 4, caddr); addr = ((caddr[0]<<24) & 0xff000000); addr |= ((caddr[1] <<16) & 0xff0000); addr |= ((caddr[2] <<8) & 0xff00); addr |= (caddr[3] & 0xff); addr = htonl(addr); inf.sin_addr.s_addr = addr; inf.sin_family = AF_INET; inf.sin_port = 0; netif = &inf; } /* * Let's try to create a RAW socket to send ICMP packets * This usually requires "root" privileges, so it's likely to fail. */ fd = JVM_Socket(AF_INET, SOCK_RAW, IPPROTO_ICMP); if (fd != -1) { /* * It didn't fail, so we can use ICMP_ECHO requests. */ return ping4(env, fd, &him, timeout, netif, ttl); } /* * Can't create a raw socket, so let's try a TCP socket */ fd = JVM_Socket(AF_INET, SOCK_STREAM, 0); if (fd == JVM_IO_ERR) { /* note: if you run out of fds, you may not be able to load * the exception class, and get a NoClassDefFoundError * instead. */ NET_ThrowNew(env, errno, "Can't create socket"); return JNI_FALSE; } if (ttl > 0) { setsockopt(fd, IPPROTO_IP, IP_TTL, &ttl, sizeof(ttl)); } /* * A network interface was specified, so let's bind to it. */ if (netif != NULL) { if (bind(fd, (struct sockaddr*)netif, sizeof(struct sockaddr_in)) < 0) { NET_ThrowNew(env, errno, "Can't bind socket"); close(fd); return JNI_FALSE; } } /* * Make the socket non blocking so we can use select/poll. */ SET_NONBLOCKING(fd); /* no need to use NET_Connect as non-blocking */ him.sin_port = htons(7); /* Echo */ connect_rv = JVM_Connect(fd, (struct sockaddr *)&him, len); /** * connection established or refused immediately, either way it means * we were able to reach the host! */ if (connect_rv == 0 || errno == ECONNREFUSED) { close(fd); return JNI_TRUE; } else { int optlen; switch (errno) { case ENETUNREACH: /* Network Unreachable */ case EAFNOSUPPORT: /* Address Family not supported */ case EADDRNOTAVAIL: /* address is not available on the remote machine */ #ifdef __linux__ case EINVAL: /* * On some Linuxes, when bound to the loopback interface, connect * will fail and errno will be set to EINVAL. When that happens, * don't throw an exception, just return false. */ #endif /* __linux__ */ close(fd); return JNI_FALSE; } if (errno != EINPROGRESS) { NET_ThrowByNameWithLastError(env, JNU_JAVANETPKG "ConnectException", "connect failed"); close(fd); return JNI_FALSE; } timeout = NET_Wait(env, fd, NET_WAIT_CONNECT, timeout); if (timeout >= 0) { /* has connection been established? */ optlen = sizeof(connect_rv); if (JVM_GetSockOpt(fd, SOL_SOCKET, SO_ERROR, (void*)&connect_rv, &optlen) <0) { connect_rv = errno; } if (connect_rv == 0 || connect_rv == ECONNREFUSED) { close(fd); return JNI_TRUE; } } close(fd); return JNI_FALSE; } }