blob: b3eaae49cb05fc7cebae053dcc459cc57c5c3f79 [file] [log] [blame]
#include <net-snmp/net-snmp-config.h>
#include <net-snmp/library/snmpUDPIPv6Domain.h>
#include <net-snmp/library/system.h>
#include <net-snmp/types.h>
#ifdef NETSNMP_TRANSPORT_UDPIPV6_DOMAIN
#include <stdio.h>
#include <sys/types.h>
#include <ctype.h>
#include <errno.h>
#if HAVE_STRING_H
#include <string.h>
#else
#include <strings.h>
#endif
#include <stddef.h>
#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 defined(HAVE_WINSOCK_H) && !defined(mingw32)
static const struct in6_addr in6addr_any = IN6ADDR_ANY_INIT;
#endif
#if HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#if HAVE_ARPA_INET_H
#include <arpa/inet.h>
#endif
#if HAVE_NETDB_H
#include <netdb.h>
#endif
#if HAVE_NET_IF_H
#include <net/if.h>
#endif
#if HAVE_DMALLOC_H
#include <dmalloc.h>
#endif
#if HAVE_STRUCT_SOCKADDR_STORAGE_SS_FAMILY
#define SS_FAMILY ss_family
#elif HAVE_STRUCT_SOCKADDR_STORAGE___SS_FAMILY
#define SS_FAMILY __ss_family
#endif
#if defined(darwin)
#include <stdint.h> /* for uint8_t */
#endif
#include <net-snmp/types.h>
#include <net-snmp/output_api.h>
#include <net-snmp/config_api.h>
#include <net-snmp/library/snmp_transport.h>
#include <net-snmp/library/snmpSocketBaseDomain.h>
#include <net-snmp/library/tools.h>
#include "inet_ntop.h"
#include "inet_pton.h"
oid netsnmp_UDPIPv6Domain[] = { TRANSPORT_DOMAIN_UDP_IPV6 };
static netsnmp_tdomain udp6Domain;
/*
* from snmpUDPDomain. not static, but not public, either.
* (ie don't put it in a public header.)
*/
extern void _netsnmp_udp_sockopt_set(int fd, int server);
/*
* Return a string representing the address in data, or else the "far end"
* address if data is NULL.
*/
static char *
netsnmp_udp6_fmtaddr(netsnmp_transport *t, void *data, int len)
{
return netsnmp_ipv6_fmtaddr("UDP/IPv6", t, data, len);
}
/*
* 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_udp6_recv(netsnmp_transport *t, void *buf, int size,
void **opaque, int *olength)
{
int rc = -1;
socklen_t fromlen = sizeof(struct sockaddr_in6);
struct sockaddr *from;
if (t != NULL && t->sock >= 0) {
from = (struct sockaddr *) malloc(sizeof(struct sockaddr_in6));
if (from == NULL) {
*opaque = NULL;
*olength = 0;
return -1;
} else {
memset(from, 0, fromlen);
}
while (rc < 0) {
rc = recvfrom(t->sock, buf, size, 0, from, &fromlen);
if (rc < 0 && errno != EINTR) {
break;
}
}
if (rc >= 0) {
DEBUGIF("netsnmp_udp6") {
char *str = netsnmp_udp6_fmtaddr(NULL, from, fromlen);
DEBUGMSGTL(("netsnmp_udp6",
"recvfrom fd %d got %d bytes (from %s)\n", t->sock,
rc, str));
free(str);
}
} else {
DEBUGMSGTL(("netsnmp_udp6", "recvfrom fd %d err %d (\"%s\")\n",
t->sock, errno, strerror(errno)));
}
*opaque = (void *) from;
*olength = sizeof(struct sockaddr_in6);
}
return rc;
}
static int
netsnmp_udp6_send(netsnmp_transport *t, void *buf, int size,
void **opaque, int *olength)
{
int rc = -1;
struct sockaddr *to = NULL;
if (opaque != NULL && *opaque != NULL &&
*olength == sizeof(struct sockaddr_in6)) {
to = (struct sockaddr *) (*opaque);
} else if (t != NULL && t->data != NULL &&
((t->data_length == sizeof(struct sockaddr_in6)) ||
(t->data_length == sizeof(netsnmp_indexed_addr_pair)))) {
to = (struct sockaddr *) (t->data);
}
if (to != NULL && t != NULL && t->sock >= 0) {
DEBUGIF("netsnmp_udp6") {
char *str = netsnmp_udp6_fmtaddr(NULL, (void *)to,
sizeof(struct sockaddr_in6));
DEBUGMSGTL(("netsnmp_udp6",
"send %d bytes from %p to %s on fd %d\n",
size, buf, str, t->sock));
free(str);
}
while (rc < 0) {
rc = sendto(t->sock, buf, size, 0, to,sizeof(struct sockaddr_in6));
if (rc < 0 && errno != EINTR) {
break;
}
}
}
return rc;
}
/*
* Open a UDP/IPv6-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_udp6_transport(struct sockaddr_in6 *addr, int local)
{
netsnmp_transport *t = NULL;
int rc = 0;
#ifdef NETSNMP_NO_LISTEN_SUPPORT
if (local)
return NULL;
#endif /* NETSNMP_NO_LISTEN_SUPPORT */
if (addr == NULL || addr->sin6_family != AF_INET6) {
return NULL;
}
t = SNMP_MALLOC_TYPEDEF(netsnmp_transport);
if (t == NULL) {
return NULL;
}
DEBUGIF("netsnmp_udp6") {
char *str = netsnmp_udp6_fmtaddr(NULL, (void *) addr,
sizeof(struct sockaddr_in6));
DEBUGMSGTL(("netsnmp_udp6", "open %s %s\n", local ? "local" : "remote",
str));
free(str);
}
t->domain = netsnmp_UDPIPv6Domain;
t->domain_length =
sizeof(netsnmp_UDPIPv6Domain) / sizeof(netsnmp_UDPIPv6Domain[0]);
t->sock = socket(PF_INET6, SOCK_DGRAM, 0);
if (t->sock < 0) {
netsnmp_transport_free(t);
return NULL;
}
_netsnmp_udp_sockopt_set(t->sock, local);
if (local) {
#ifndef NETSNMP_NO_LISTEN_SUPPORT
/*
* This session is intended as a server, so we must bind on to the
* given IP address, which may include an interface address, or could
* be INADDR_ANY, but certainly includes a port number.
*/
#ifdef IPV6_V6ONLY
/* Try to restrict PF_INET6 socket to IPv6 communications only. */
{
int one=1;
if (setsockopt(t->sock, IPPROTO_IPV6, IPV6_V6ONLY, (char *)&one, sizeof(one)) != 0) {
DEBUGMSGTL(("netsnmp_udp6", "couldn't set IPV6_V6ONLY to %d bytes: %s\n", one, strerror(errno)));
}
}
#endif
rc = bind(t->sock, (struct sockaddr *) addr,
sizeof(struct sockaddr_in6));
if (rc != 0) {
netsnmp_socketbase_close(t);
netsnmp_transport_free(t);
return NULL;
}
t->local = (unsigned char*)malloc(18);
if (t->local == NULL) {
netsnmp_socketbase_close(t);
netsnmp_transport_free(t);
return NULL;
}
memcpy(t->local, addr->sin6_addr.s6_addr, 16);
t->local[16] = (addr->sin6_port & 0xff00) >> 8;
t->local[17] = (addr->sin6_port & 0x00ff) >> 0;
t->local_length = 18;
t->data = NULL;
t->data_length = 0;
#else /* NETSNMP_NO_LISTEN_SUPPORT */
return NULL;
#endif /* NETSNMP_NO_LISTEN_SUPPORT */
} else {
/*
* This is a client session. Save the address in the
* transport-specific data pointer for later use by netsnmp_udp6_send.
*/
t->data = malloc(sizeof(netsnmp_indexed_addr_pair));
if (t->data == NULL) {
netsnmp_socketbase_close(t);
netsnmp_transport_free(t);
return NULL;
}
memcpy(t->data, addr, sizeof(struct sockaddr_in6));
t->data_length = sizeof(netsnmp_indexed_addr_pair);
t->remote = (unsigned char*)malloc(18);
if (t->remote == NULL) {
netsnmp_socketbase_close(t);
netsnmp_transport_free(t);
return NULL;
}
memcpy(t->remote, addr->sin6_addr.s6_addr, 16);
t->remote[16] = (addr->sin6_port & 0xff00) >> 8;
t->remote[17] = (addr->sin6_port & 0x00ff) >> 0;
t->remote_length = 18;
}
/*
* 16-bit length field, 8 byte UDP header, 40 byte IPv6 header.
*/
t->msgMaxSize = 0xffff - 8 - 40;
t->f_recv = netsnmp_udp6_recv;
t->f_send = netsnmp_udp6_send;
t->f_close = netsnmp_socketbase_close;
t->f_accept = NULL;
t->f_fmtaddr = netsnmp_udp6_fmtaddr;
return t;
}
#if !defined(NETSNMP_DISABLE_SNMPV1) || !defined(NETSNMP_DISABLE_SNMPV2C)
/*
* The following functions provide the "com2sec6" configuration token
* functionality for compatibility.
*/
#define EXAMPLE_NETWORK "NETWORK"
#define EXAMPLE_COMMUNITY "COMMUNITY"
typedef struct com2Sec6Entry_s {
const char *secName;
const char *contextName;
struct com2Sec6Entry_s *next;
struct in6_addr network;
struct in6_addr mask;
const char community[1];
} com2Sec6Entry;
static com2Sec6Entry *com2Sec6List = NULL, *com2Sec6ListLast = NULL;
NETSNMP_STATIC_INLINE int
create_com2Sec6Entry(const struct addrinfo* const run,
const struct in6_addr* const mask,
const char* const secName,
const size_t secNameLen,
const char* const contextName,
const size_t contextNameLen,
const char* const community,
const size_t communityLen,
com2Sec6Entry** const begin,
com2Sec6Entry** const end)
{
const struct sockaddr_in6 * const run_addr =
(const struct sockaddr_in6*)run->ai_addr;
int i;
/* Check that the network and mask are consistent. */
for (i = 0; i < 16; ++i) {
if (run_addr->sin6_addr.s6_addr[i] & ~mask->s6_addr[i]) {
config_perror("source/mask mismatch");
return 1;
}
}
{
char buf1[INET6_ADDRSTRLEN];
char buf2[INET6_ADDRSTRLEN];
DEBUGMSGTL(("netsnmp_udp6_parse_security",
"<\"%s\", %s/%s> => \"%s\"\n",
community,
inet_ntop(AF_INET6, &run_addr->sin6_addr,
buf1, sizeof(buf1)),
inet_ntop(AF_INET6, mask, buf2, sizeof(buf2)),
secName));
}
{
/* Allocate all the needed chunks */
void * const v =
malloc(offsetof(com2Sec6Entry, community) + communityLen +
secNameLen + contextNameLen);
com2Sec6Entry* const e = (com2Sec6Entry*)v;
char *last = ((char*)v) + offsetof(com2Sec6Entry, community);
if (v == NULL) {
config_perror("memory error");
return 1;
}
memcpy(last, community, communityLen);
last += communityLen;
memcpy(last, secName, secNameLen);
e->secName = last;
last += secNameLen;
if (contextNameLen) {
memcpy(last, contextName, contextNameLen);
e->contextName = last;
} else
e->contextName = last - 1;
memcpy(&e->network, &run_addr->sin6_addr, sizeof(struct in6_addr));
memcpy(&e->mask, mask, sizeof(struct in6_addr));
e->next = NULL;
if (*end != NULL) {
(*end)->next = e;
*end = e;
} else {
*end = *begin = e;
}
}
return 0;
}
void
netsnmp_udp6_parse_security(const char *token, char *param)
{
char secName[VACMSTRINGLEN + 1];
size_t secNameLen;
char contextName[VACMSTRINGLEN + 1];
size_t contextNameLen;
char community[COMMUNITY_MAX_LEN + 1];
size_t communityLen;
char source[300]; /* dns-name(253)+/(1)+mask(45)+\0(1) */
struct in6_addr mask;
/*
* Get security, source address/netmask and community strings.
*/
param = copy_nword( param, secName, sizeof(secName));
if (strcmp(secName, "-Cn") == 0) {
if (!param) {
config_perror("missing CONTEXT_NAME parameter");
return;
}
param = copy_nword( param, contextName, sizeof(contextName));
contextNameLen = strlen(contextName) + 1;
if (contextNameLen > VACMSTRINGLEN) {
config_perror("context name too long");
return;
}
if (!param) {
config_perror("missing NAME parameter");
return;
}
param = copy_nword( param, secName, sizeof(secName));
} else {
contextNameLen = 0;
}
secNameLen = strlen(secName) + 1;
if (secNameLen == 1) {
config_perror("empty NAME parameter");
return;
} else if (secNameLen > VACMSTRINGLEN) {
config_perror("security name too long");
return;
}
if (!param) {
config_perror("missing SOURCE parameter");
return;
}
param = copy_nword( param, source, sizeof(source));
if (source[0] == '\0') {
config_perror("empty SOURCE parameter");
return;
}
if (strncmp(source, EXAMPLE_NETWORK, strlen(EXAMPLE_NETWORK)) == 0) {
config_perror("example config NETWORK not properly configured");
return;
}
if (!param) {
config_perror("missing COMMUNITY parameter");
return;
}
param = copy_nword( param, community, sizeof(community));
if (community[0] == '\0') {
config_perror("empty COMMUNITY parameter");
return;
}
communityLen = strlen(community) + 1;
if (communityLen >= COMMUNITY_MAX_LEN) {
config_perror("community name too long");
return;
}
if (communityLen == sizeof(EXAMPLE_COMMUNITY) &&
memcmp(community, EXAMPLE_COMMUNITY, sizeof(EXAMPLE_COMMUNITY)) == 0) {
config_perror("example config COMMUNITY not properly configured");
return;
}
/* Possible mask cases
* "default" <=> 0::0/0
* <hostname>[/] <=> <hostname>/128
* <hostname>/number <=> <hostname>/number
* <hostname>/<mask> <=> <hostname>/<mask>
*/
{
/* Deal with the "default" case first. */
const int isdefault = strcmp(source, "default") == 0;
if (isdefault) {
memset(mask.s6_addr, '\0', sizeof(mask.s6_addr));
} else {
/* Split the source/netmask parts */
char *strmask = strchr(source, '/');
if (strmask != NULL)
/* Mask given. */
*strmask++ = '\0';
/* Try to interpret the mask */
if (strmask == NULL || *strmask == '\0') {
/* No mask was given. Assume /128 */
memset(mask.s6_addr, '\xff', sizeof(mask.s6_addr));
} else {
/* Try to interpret mask as a "number of 1 bits". */
char* cp;
long masklength = strtol(strmask, &cp, 10);
if (*cp == '\0') {
if (0 <= masklength && masklength <= 128) {
const int j = masklength / 8;
const int jj = masklength % 8;
memset(mask.s6_addr, '\xff', j);
if (j < 16) {
mask.s6_addr[j] = ((uint8_t)~0U << (8 - jj));
memset(mask.s6_addr + j + 1, '\0', 15 - j);
}
} else {
config_perror("bad mask length");
return;
}
}
/* Try to interpret mask numerically. */
else if (inet_pton(AF_INET6, strmask, &mask) != 1) {
config_perror("bad mask");
return;
}
}
}
{
struct sockaddr_in6 pton_addr;
struct addrinfo hints, *res = NULL;
memset(&hints, '\0', sizeof(hints));
/* First check if default, otherwise try to parse as a numeric
* address, if that also fails try to lookup the address */
if (isdefault) {
memset(&pton_addr.sin6_addr.s6_addr, '\0',
sizeof(struct in6_addr));
} else if (inet_pton(AF_INET6, source, &pton_addr.sin6_addr) != 1) {
/* Nope, wasn't a numeric address. Must be a hostname. */
#if HAVE_GETADDRINFO
int gai_error;
hints.ai_family = AF_INET6;
hints.ai_socktype = SOCK_DGRAM;
gai_error = netsnmp_getaddrinfo(source, NULL, &hints, &res);
if (gai_error != 0) {
config_perror(gai_strerror(gai_error));
return;
}
#else
config_perror("getaddrinfo() not available");
return;
#endif
}
if (res == NULL) {
hints.ai_addrlen = sizeof(pton_addr);
hints.ai_addr = (struct sockaddr*)&pton_addr;
hints.ai_next = NULL;
res = &hints;
}
{
struct addrinfo *run;
int failed = 0;
com2Sec6Entry *begin = NULL, *end = NULL;
for (run = res; run && !failed; run = run->ai_next)
failed =
create_com2Sec6Entry(run, &mask,
secName, secNameLen,
contextName, contextNameLen,
community, communityLen,
&begin, &end);
if (failed) {
/* Free eventually allocated chunks */
while (begin) {
end = begin;
begin = begin->next;
free(end);
}
} else if (com2Sec6ListLast != NULL) {
com2Sec6ListLast->next = begin;
com2Sec6ListLast = end;
} else {
com2Sec6List = begin;
com2Sec6ListLast = end;
}
}
#if HAVE_GETADDRINFO
if (res != &hints)
freeaddrinfo(res);
#endif
}
}
}
void
netsnmp_udp6_com2Sec6List_free(void)
{
com2Sec6Entry *e = com2Sec6List;
while (e != NULL) {
com2Sec6Entry *tmp = e;
e = e->next;
free(tmp);
}
com2Sec6List = com2Sec6ListLast = NULL;
}
#endif /* support for community based SNMP */
void
netsnmp_udp6_agent_config_tokens_register(void)
{
#if !defined(NETSNMP_DISABLE_SNMPV1) || !defined(NETSNMP_DISABLE_SNMPV2C)
register_app_config_handler("com2sec6", netsnmp_udp6_parse_security,
netsnmp_udp6_com2Sec6List_free,
"[-Cn CONTEXT] secName IPv6-network-address[/netmask] community");
#endif /* support for community based SNMP */
}
#if !defined(NETSNMP_DISABLE_SNMPV1) || !defined(NETSNMP_DISABLE_SNMPV2C)
/*
* Return 0 if there are no com2sec entries, or return 1 if there ARE com2sec
* entries. On return, if a com2sec entry matched the passed parameters,
* then *secName points at the appropriate security name, or is NULL if the
* parameters did not match any com2sec entry.
*/
int
netsnmp_udp6_getSecName(void *opaque, int olength,
const char *community,
int community_len,
const char **secName, const char **contextName)
{
const com2Sec6Entry *c;
struct sockaddr_in6 *from = (struct sockaddr_in6 *) opaque;
char *ztcommunity = NULL;
char str6[INET6_ADDRSTRLEN];
if (secName != NULL) {
*secName = NULL; /* Haven't found anything yet */
}
/*
* Special case if there are NO entries (as opposed to no MATCHING
* entries).
*/
if (com2Sec6List == NULL) {
DEBUGMSGTL(("netsnmp_udp6_getSecName", "no com2sec entries\n"));
return 0;
}
/*
* If there is no IPv6 source address, then there can be no valid security
* name.
*/
if (opaque == NULL || olength != sizeof(struct sockaddr_in6)
|| from->sin6_family != PF_INET6) {
DEBUGMSGTL(("netsnmp_udp6_getSecName",
"no IPv6 source address in PDU?\n"));
return 1;
}
ztcommunity = (char *) malloc(community_len + 1);
if (ztcommunity != NULL) {
memcpy(ztcommunity, community, community_len);
ztcommunity[community_len] = '\0';
}
inet_ntop(AF_INET6, &from->sin6_addr, str6, sizeof(str6));
DEBUGMSGTL(("netsnmp_udp6_getSecName", "resolve <\"%s\", %s>\n",
ztcommunity ? ztcommunity : "<malloc error>", str6));
for (c = com2Sec6List; c != NULL; c = c->next) {
{
char buf1[INET6_ADDRSTRLEN];
char buf2[INET6_ADDRSTRLEN];
DEBUGMSGTL(("netsnmp_udp6_getSecName",
"compare <\"%s\", %s/%s>", c->community,
inet_ntop(AF_INET6, &c->network, buf1, sizeof(buf1)),
inet_ntop(AF_INET6, &c->mask, buf2, sizeof(buf2))));
}
if ((community_len == (int)strlen(c->community)) &&
(memcmp(community, c->community, community_len) == 0)) {
int i, ok = 1;
for (i = 0; ok && i < 16; ++i)
if ((from->sin6_addr.s6_addr[i] & c->mask.s6_addr[i]) !=
c->network.s6_addr[i])
ok = 0;
if (ok) {
DEBUGMSG(("netsnmp_udp6_getSecName", "... SUCCESS\n"));
if (secName != NULL) {
*secName = c->secName;
*contextName = c->contextName;
}
}
}
}
DEBUGMSG(("netsnmp_udp6_getSecName", "... nope\n"));
if (ztcommunity != NULL) {
free(ztcommunity);
}
return 1;
}
#endif /* support for community based SNMP */
netsnmp_transport *
netsnmp_udp6_create_tstring(const char *str, int local,
const char *default_target)
{
struct sockaddr_in6 addr;
if (netsnmp_sockaddr_in6_2(&addr, str, default_target)) {
return netsnmp_udp6_transport(&addr, local);
} else {
return NULL;
}
}
/*
* See:
*
* http://www.ietf.org/internet-drafts/draft-ietf-ops-taddress-mib-01.txt
*
* (or newer equivalent) for details of the TC which we are using for
* the mapping here.
*/
netsnmp_transport *
netsnmp_udp6_create_ostring(const u_char * o, size_t o_len, int local)
{
struct sockaddr_in6 addr;
if (o_len == 18) {
memset((u_char *) & addr, 0, sizeof(struct sockaddr_in6));
addr.sin6_family = AF_INET6;
memcpy((u_char *) & (addr.sin6_addr.s6_addr), o, 16);
addr.sin6_port = (o[16] << 8) + o[17];
return netsnmp_udp6_transport(&addr, local);
}
return NULL;
}
void
netsnmp_udpipv6_ctor(void)
{
udp6Domain.name = netsnmp_UDPIPv6Domain;
udp6Domain.name_length = sizeof(netsnmp_UDPIPv6Domain) / sizeof(oid);
udp6Domain.f_create_from_tstring = NULL;
udp6Domain.f_create_from_tstring_new = netsnmp_udp6_create_tstring;
udp6Domain.f_create_from_ostring = netsnmp_udp6_create_ostring;
udp6Domain.prefix = (const char**)calloc(5, sizeof(char *));
udp6Domain.prefix[0] = "udp6";
udp6Domain.prefix[1] = "ipv6";
udp6Domain.prefix[2] = "udpv6";
udp6Domain.prefix[3] = "udpipv6";
netsnmp_tdomain_register(&udp6Domain);
}
#else
#ifdef NETSNMP_DLL
/* need this hook for win32 MSVC++ DLL build */
void
netsnmp_udp6_agent_config_tokens_register(void)
{ }
#endif
#endif /* NETSNMP_TRANSPORT_UDPIPV6_DOMAIN */