summaryrefslogtreecommitdiff
path: root/snmplib/transports/snmpTCPDomain.c
diff options
context:
space:
mode:
Diffstat (limited to 'snmplib/transports/snmpTCPDomain.c')
-rw-r--r--snmplib/transports/snmpTCPDomain.c351
1 files changed, 351 insertions, 0 deletions
diff --git a/snmplib/transports/snmpTCPDomain.c b/snmplib/transports/snmpTCPDomain.c
new file mode 100644
index 0000000..b8bdba4
--- /dev/null
+++ b/snmplib/transports/snmpTCPDomain.c
@@ -0,0 +1,351 @@
+#include <net-snmp/net-snmp-config.h>
+
+#include <net-snmp/types.h>
+#include <net-snmp/library/snmpTCPDomain.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_DMALLOC_H
+#include <dmalloc.h>
+#endif
+
+#include <net-snmp/types.h>
+#include <net-snmp/output_api.h>
+
+#include <net-snmp/library/snmpIPv4BaseDomain.h>
+#include <net-snmp/library/snmpSocketBaseDomain.h>
+#include <net-snmp/library/snmpTCPBaseDomain.h>
+#include <net-snmp/library/tools.h>
+
+/*
+ * needs to be in sync with the definitions in snmplib/snmpUDPDomain.c
+ * and perl/agent/agent.xs
+ */
+typedef netsnmp_indexed_addr_pair 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)
+{
+ return netsnmp_ipv4_fmtaddr("TCP", t, data, len);
+}
+
+static int
+netsnmp_tcp_accept(netsnmp_transport *t)
+{
+ struct sockaddr *farend = NULL;
+ netsnmp_udp_addr_pair *addr_pair = NULL;
+ int newsock = -1;
+ socklen_t farendlen = sizeof(netsnmp_udp_addr_pair);
+
+ addr_pair = (netsnmp_udp_addr_pair *)malloc(farendlen);
+ if (addr_pair == NULL) {
+ /*
+ * Indicate that the acceptance of this socket failed.
+ */
+ DEBUGMSGTL(("netsnmp_tcp", "accept: malloc failed\n"));
+ return -1;
+ }
+ memset(addr_pair, 0, sizeof *addr_pair);
+ farend = &addr_pair->remote_addr.sa;
+
+ 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(addr_pair);
+ return newsock;
+ }
+
+ if (t->data != NULL) {
+ free(t->data);
+ }
+
+ t->data = addr_pair;
+ t->data_length = sizeof(netsnmp_udp_addr_pair);
+ DEBUGIF("netsnmp_tcp") {
+ char *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.
+ */
+
+ if (netsnmp_set_non_blocking_mode(newsock, FALSE) < 0)
+ DEBUGMSGTL(("netsnmp_tcp", "couldn't f_getfl of fd %d\n",
+ newsock));
+
+ /*
+ * 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(addr_pair);
+ 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;
+
+#ifdef NETSNMP_NO_LISTEN_SUPPORT
+ if (local)
+ return NULL;
+#endif /* NETSNMP_NO_LISTEN_SUPPORT */
+
+ if (addr == NULL || addr->sin_family != AF_INET) {
+ return NULL;
+ }
+
+ t = SNMP_MALLOC_TYPEDEF(netsnmp_transport);
+ if (t == NULL) {
+ return NULL;
+ }
+
+ addr_pair = (netsnmp_udp_addr_pair *)malloc(sizeof(netsnmp_udp_addr_pair));
+ if (addr_pair == NULL) {
+ netsnmp_transport_free(t);
+ return NULL;
+ }
+ memset(addr_pair, 0, sizeof *addr_pair);
+ 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) {
+#ifndef NETSNMP_NO_LISTEN_SUPPORT
+ 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_socketbase_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_socketbase_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 non-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.
+ */
+
+ netsnmp_set_non_blocking_mode(t->sock, TRUE);
+
+ /*
+ * Now sit here and wait for connections to arrive.
+ */
+
+ rc = listen(t->sock, NETSNMP_STREAM_QUEUE_LEN);
+ if (rc != 0) {
+ netsnmp_socketbase_close(t);
+ netsnmp_transport_free(t);
+ return NULL;
+ }
+
+ /*
+ * no buffer size on listen socket - doesn't make sense
+ */
+#else /* NETSNMP_NO_LISTEN_SUPPORT */
+ return NULL;
+#endif /* NETSNMP_NO_LISTEN_SUPPORT */
+ } else {
+ t->remote = (u_char *)malloc(6);
+ if (t->remote == NULL) {
+ netsnmp_socketbase_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_socketbase_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_tcpbase_recv;
+ t->f_send = netsnmp_tcpbase_send;
+ t->f_close = netsnmp_socketbase_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);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-22 01:06:00 +0000