| #include <net-snmp/net-snmp-config.h> |
| |
| #include <stdio.h> |
| #include <sys/types.h> |
| #include <errno.h> |
| |
| #if HAVE_STRING_H |
| #include <string.h> |
| #else |
| #include <strings.h> |
| #endif |
| #if HAVE_STDLIB_H |
| #include <stdlib.h> |
| #endif |
| #if HAVE_UNISTD_H |
| #include <unistd.h> |
| #endif |
| #if HAVE_SYS_SOCKET_H |
| #include <sys/socket.h> |
| #endif |
| #if HAVE_NETINET_IN_H |
| #include <netinet/in.h> |
| #endif |
| #if HAVE_ARPA_INET_H |
| #include <arpa/inet.h> |
| #endif |
| #if HAVE_FCNTL_H |
| #include <fcntl.h> |
| #endif |
| |
| #if HAVE_WINSOCK_H |
| #include <winsock2.h> |
| #include <ws2tcpip.h> |
| #endif |
| |
| #if HAVE_DMALLOC_H |
| #include <dmalloc.h> |
| #endif |
| |
| #include <net-snmp/types.h> |
| #include <net-snmp/output_api.h> |
| |
| #include <net-snmp/library/snmp_transport.h> |
| #include <net-snmp/library/snmpUDPDomain.h> |
| #include <net-snmp/library/snmpTCPDomain.h> |
| |
| /* Copied from snmpUDPDomain.c */ |
| typedef struct netsnmp_udp_addr_pair_s { |
| struct sockaddr_in remote_addr; |
| struct in_addr local_addr; |
| } netsnmp_udp_addr_pair; |
| |
| oid netsnmp_snmpTCPDomain[] = { TRANSPORT_DOMAIN_TCP_IP }; |
| static netsnmp_tdomain tcpDomain; |
| |
| /* |
| * Not static since it is needed here as well as in snmpUDPDomain, but not |
| * public either |
| */ |
| int |
| netsnmp_sockaddr_in2(struct sockaddr_in *addr, |
| const char *inpeername, const char *default_target); |
| |
| /* |
| * Return a string representing the address in data, or else the "far end" |
| * address if data is NULL. |
| */ |
| |
| static char * |
| netsnmp_tcp_fmtaddr(netsnmp_transport *t, void *data, int len) |
| { |
| netsnmp_udp_addr_pair *addr_pair = NULL; |
| |
| if (data != NULL && len == sizeof(netsnmp_udp_addr_pair)) { |
| addr_pair = (netsnmp_udp_addr_pair *) data; |
| } else if (t != NULL && t->data != NULL) { |
| addr_pair = (netsnmp_udp_addr_pair *) t->data; |
| } |
| |
| if (addr_pair == NULL) { |
| return strdup("TCP: unknown"); |
| } else { |
| struct sockaddr_in *to = NULL; |
| char tmp[64]; |
| to = (struct sockaddr_in *) &(addr_pair->remote_addr); |
| if (to == NULL) { |
| return strdup("TCP: unknown"); |
| } |
| |
| sprintf(tmp, "TCP: [%s]:%hu", |
| inet_ntoa(to->sin_addr), ntohs(to->sin_port)); |
| return strdup(tmp); |
| } |
| } |
| |
| |
| |
| /* |
| * You can write something into opaque that will subsequently get passed back |
| * to your send function if you like. For instance, you might want to |
| * remember where a PDU came from, so that you can send a reply there... |
| */ |
| |
| static int |
| netsnmp_tcp_recv(netsnmp_transport *t, void *buf, int size, |
| void **opaque, int *olength) |
| { |
| int rc = -1; |
| |
| if (t != NULL && t->sock >= 0) { |
| while (rc < 0) { |
| rc = recvfrom(t->sock, buf, size, 0, NULL, 0); |
| if (rc < 0 && errno != EINTR) { |
| DEBUGMSGTL(("netsnmp_tcp", "recv fd %d err %d (\"%s\")\n", |
| t->sock, errno, strerror(errno))); |
| break; |
| } |
| DEBUGMSGTL(("netsnmp_tcp", "recv fd %d got %d bytes\n", |
| t->sock, rc)); |
| } |
| } else { |
| return -1; |
| } |
| |
| if (opaque != NULL && olength != NULL) { |
| if (t->data_length > 0) { |
| if ((*opaque = malloc(t->data_length)) != NULL) { |
| memcpy(*opaque, t->data, t->data_length); |
| *olength = t->data_length; |
| } else { |
| *olength = 0; |
| } |
| } else { |
| *opaque = NULL; |
| *olength = 0; |
| } |
| } |
| |
| return rc; |
| } |
| |
| |
| |
| static int |
| netsnmp_tcp_send(netsnmp_transport *t, void *buf, int size, |
| void **opaque, int *olength) |
| { |
| int rc = -1; |
| |
| if (t != NULL && t->sock >= 0) { |
| while (rc < 0) { |
| rc = sendto(t->sock, buf, size, 0, NULL, 0); |
| if (rc < 0 && errno != EINTR) { |
| break; |
| } |
| } |
| } |
| return rc; |
| } |
| |
| |
| |
| static int |
| netsnmp_tcp_close(netsnmp_transport *t) |
| { |
| int rc = -1; |
| if (t != NULL && t->sock >= 0) { |
| DEBUGMSGTL(("netsnmp_tcp", "close fd %d\n", t->sock)); |
| #ifndef HAVE_CLOSESOCKET |
| rc = close(t->sock); |
| #else |
| rc = closesocket(t->sock); |
| #endif |
| t->sock = -1; |
| } |
| return rc; |
| } |
| |
| |
| |
| static int |
| netsnmp_tcp_accept(netsnmp_transport *t) |
| { |
| struct sockaddr *farend = NULL; |
| netsnmp_udp_addr_pair *addr_pair = NULL; |
| int newsock = -1; |
| #ifdef WIN32 |
| u_long ioctlsocket_opt; |
| #else |
| int sockflags; |
| #endif |
| socklen_t farendlen = sizeof(struct sockaddr_in); |
| char *str = NULL; |
| |
| addr_pair = (netsnmp_udp_addr_pair *)malloc(sizeof(netsnmp_udp_addr_pair)); |
| |
| if (addr_pair == NULL) { |
| /* |
| * Indicate that the acceptance of this socket failed. |
| */ |
| DEBUGMSGTL(("netsnmp_tcp", "accept: malloc failed\n")); |
| return -1; |
| } |
| farend = (struct sockaddr *) &(addr_pair->remote_addr); |
| |
| if (t != NULL && t->sock >= 0) { |
| newsock = accept(t->sock, farend, &farendlen); |
| |
| if (newsock < 0) { |
| DEBUGMSGTL(("netsnmp_tcp", "accept failed rc %d errno %d \"%s\"\n", |
| newsock, errno, strerror(errno))); |
| free(farend); |
| return newsock; |
| } |
| |
| if (t->data != NULL) { |
| free(t->data); |
| } |
| |
| t->data = addr_pair; |
| t->data_length = sizeof(netsnmp_udp_addr_pair); |
| str = netsnmp_tcp_fmtaddr(NULL, farend, farendlen); |
| DEBUGMSGTL(("netsnmp_tcp", "accept succeeded (from %s)\n", str)); |
| free(str); |
| |
| /* |
| * Try to make the new socket blocking. |
| */ |
| |
| #ifdef WIN32 |
| ioctlsocket_opt = 0; |
| ioctlsocket(newsock, FIONBIO, &ioctlsocket_opt); |
| #else |
| if ((sockflags = fcntl(newsock, F_GETFL, 0)) >= 0) { |
| fcntl(newsock, F_SETFL, (sockflags & ~O_NONBLOCK)); |
| } else { |
| DEBUGMSGTL(("netsnmp_tcp", "couldn't f_getfl of fd %d\n",newsock)); |
| } |
| #endif |
| |
| /* |
| * Allow user to override the send and receive buffers. Default is |
| * to use os default. Don't worry too much about errors -- |
| * just plough on regardless. |
| */ |
| netsnmp_sock_buffer_set(newsock, SO_SNDBUF, 1, 0); |
| netsnmp_sock_buffer_set(newsock, SO_RCVBUF, 1, 0); |
| |
| return newsock; |
| } else { |
| free(farend); |
| return -1; |
| } |
| } |
| |
| |
| |
| /* |
| * Open a TCP-based transport for SNMP. Local is TRUE if addr is the local |
| * address to bind to (i.e. this is a server-type session); otherwise addr is |
| * the remote address to send things to. |
| */ |
| |
| netsnmp_transport * |
| netsnmp_tcp_transport(struct sockaddr_in *addr, int local) |
| { |
| netsnmp_transport *t = NULL; |
| netsnmp_udp_addr_pair *addr_pair = NULL; |
| int rc = 0; |
| |
| |
| if (addr == NULL || addr->sin_family != AF_INET) { |
| return NULL; |
| } |
| |
| t = (netsnmp_transport *) malloc(sizeof(netsnmp_transport)); |
| if (t == NULL) { |
| return NULL; |
| } |
| memset(t, 0, sizeof(netsnmp_transport)); |
| |
| addr_pair = (netsnmp_udp_addr_pair *)malloc(sizeof(netsnmp_udp_addr_pair)); |
| if (addr_pair == NULL) { |
| netsnmp_transport_free(t); |
| return NULL; |
| } |
| t->data = addr_pair; |
| t->data_length = sizeof(netsnmp_udp_addr_pair); |
| memcpy(&(addr_pair->remote_addr), addr, sizeof(struct sockaddr_in)); |
| |
| t->domain = netsnmp_snmpTCPDomain; |
| t->domain_length = |
| sizeof(netsnmp_snmpTCPDomain) / sizeof(netsnmp_snmpTCPDomain[0]); |
| |
| t->sock = socket(PF_INET, SOCK_STREAM, 0); |
| if (t->sock < 0) { |
| netsnmp_transport_free(t); |
| return NULL; |
| } |
| |
| t->flags = NETSNMP_TRANSPORT_FLAG_STREAM; |
| |
| if (local) { |
| #ifdef WIN32 |
| u_long ioctlsocket_opt = 1; |
| #else |
| int sockflags = 0; |
| #endif |
| int opt = 1; |
| |
| /* |
| * This session is inteneded as a server, so we must bind to the given |
| * IP address (which may include an interface address, or could be |
| * INADDR_ANY, but will always include a port number. |
| */ |
| |
| t->flags |= NETSNMP_TRANSPORT_FLAG_LISTEN; |
| t->local = (u_char *)malloc(6); |
| if (t->local == NULL) { |
| netsnmp_tcp_close(t); |
| netsnmp_transport_free(t); |
| return NULL; |
| } |
| memcpy(t->local, (u_char *) & (addr->sin_addr.s_addr), 4); |
| t->local[4] = (htons(addr->sin_port) & 0xff00) >> 8; |
| t->local[5] = (htons(addr->sin_port) & 0x00ff) >> 0; |
| t->local_length = 6; |
| |
| /* |
| * We should set SO_REUSEADDR too. |
| */ |
| |
| setsockopt(t->sock, SOL_SOCKET, SO_REUSEADDR, (void *)&opt, |
| sizeof(opt)); |
| |
| rc = bind(t->sock, (struct sockaddr *)addr, sizeof(struct sockaddr)); |
| if (rc != 0) { |
| netsnmp_tcp_close(t); |
| netsnmp_transport_free(t); |
| return NULL; |
| } |
| |
| /* |
| * Since we are going to be letting select() tell us when connections |
| * are ready to be accept()ed, we need to make the socket n0n-blocking |
| * to avoid the race condition described in W. R. Stevens, ``Unix |
| * Network Programming Volume I Second Edition'', pp. 422--4, which |
| * could otherwise wedge the agent. |
| */ |
| |
| #ifdef WIN32 |
| ioctlsocket_opt = 1; |
| ioctlsocket(t->sock, FIONBIO, &ioctlsocket_opt); |
| #else |
| sockflags = fcntl(t->sock, F_GETFL, 0); |
| fcntl(t->sock, F_SETFL, sockflags | O_NONBLOCK); |
| #endif |
| |
| /* |
| * Now sit here and wait for connections to arrive. |
| */ |
| |
| rc = listen(t->sock, NETSNMP_STREAM_QUEUE_LEN); |
| if (rc != 0) { |
| netsnmp_tcp_close(t); |
| netsnmp_transport_free(t); |
| return NULL; |
| } |
| |
| /* |
| * no buffer size on listen socket - doesn't make sense |
| */ |
| |
| } else { |
| t->remote = (u_char *)malloc(6); |
| if (t->remote == NULL) { |
| netsnmp_tcp_close(t); |
| netsnmp_transport_free(t); |
| return NULL; |
| } |
| memcpy(t->remote, (u_char *) & (addr->sin_addr.s_addr), 4); |
| t->remote[4] = (htons(addr->sin_port) & 0xff00) >> 8; |
| t->remote[5] = (htons(addr->sin_port) & 0x00ff) >> 0; |
| t->remote_length = 6; |
| |
| /* |
| * This is a client-type session, so attempt to connect to the far |
| * end. We don't go non-blocking here because it's not obvious what |
| * you'd then do if you tried to do snmp_sends before the connection |
| * had completed. So this can block. |
| */ |
| |
| rc = connect(t->sock, (struct sockaddr *)addr, |
| sizeof(struct sockaddr)); |
| |
| if (rc < 0) { |
| netsnmp_tcp_close(t); |
| netsnmp_transport_free(t); |
| return NULL; |
| } |
| |
| /* |
| * Allow user to override the send and receive buffers. Default is |
| * to use os default. Don't worry too much about errors -- |
| * just plough on regardless. |
| */ |
| netsnmp_sock_buffer_set(t->sock, SO_SNDBUF, local, 0); |
| netsnmp_sock_buffer_set(t->sock, SO_RCVBUF, local, 0); |
| } |
| |
| /* |
| * Message size is not limited by this transport (hence msgMaxSize |
| * is equal to the maximum legal size of an SNMP message). |
| */ |
| |
| t->msgMaxSize = 0x7fffffff; |
| t->f_recv = netsnmp_tcp_recv; |
| t->f_send = netsnmp_tcp_send; |
| t->f_close = netsnmp_tcp_close; |
| t->f_accept = netsnmp_tcp_accept; |
| t->f_fmtaddr = netsnmp_tcp_fmtaddr; |
| |
| return t; |
| } |
| |
| |
| |
| netsnmp_transport * |
| netsnmp_tcp_create_tstring(const char *str, int local, |
| const char *default_target) |
| { |
| struct sockaddr_in addr; |
| |
| if (netsnmp_sockaddr_in2(&addr, str, default_target)) { |
| return netsnmp_tcp_transport(&addr, local); |
| } else { |
| return NULL; |
| } |
| } |
| |
| |
| |
| netsnmp_transport * |
| netsnmp_tcp_create_ostring(const u_char * o, size_t o_len, int local) |
| { |
| struct sockaddr_in addr; |
| |
| if (o_len == 6) { |
| unsigned short porttmp = (o[4] << 8) + o[5]; |
| addr.sin_family = AF_INET; |
| memcpy((u_char *) & (addr.sin_addr.s_addr), o, 4); |
| addr.sin_port = htons(porttmp); |
| return netsnmp_tcp_transport(&addr, local); |
| } |
| return NULL; |
| } |
| |
| |
| |
| void |
| netsnmp_tcp_ctor(void) |
| { |
| tcpDomain.name = netsnmp_snmpTCPDomain; |
| tcpDomain.name_length = sizeof(netsnmp_snmpTCPDomain) / sizeof(oid); |
| tcpDomain.prefix = (const char **)calloc(2, sizeof(char *)); |
| tcpDomain.prefix[0] = "tcp"; |
| |
| tcpDomain.f_create_from_tstring = NULL; |
| tcpDomain.f_create_from_tstring_new = netsnmp_tcp_create_tstring; |
| tcpDomain.f_create_from_ostring = netsnmp_tcp_create_ostring; |
| |
| netsnmp_tdomain_register(&tcpDomain); |
| } |
