diff options
Diffstat (limited to 'lib/libc/net/sourcefilter.c')
| -rw-r--r-- | lib/libc/net/sourcefilter.c | 402 |
1 files changed, 402 insertions, 0 deletions
diff --git a/lib/libc/net/sourcefilter.c b/lib/libc/net/sourcefilter.c new file mode 100644 index 0000000..cc0f1b9 --- /dev/null +++ b/lib/libc/net/sourcefilter.c @@ -0,0 +1,402 @@ +/*- + * Copyright (c) 2007-2009 Bruce Simpson. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include "namespace.h" + +#include <sys/types.h> +#include <sys/param.h> +#include <sys/ioctl.h> +#include <sys/socket.h> + +#include <net/if_dl.h> +#include <net/if.h> +#include <netinet/in.h> +#include <netinet/in_systm.h> +#include <netinet/ip.h> +#include <netinet/ip_var.h> + +#include <assert.h> +#include <errno.h> +#include <ifaddrs.h> +#include <stdlib.h> +#include <string.h> + +#include "un-namespace.h" + +/* + * Advanced (Full-state) multicast group membership APIs [RFC3678] + * Currently this module assumes IPv4 support (INET) in the base system. + */ +#ifndef INET +#define INET +#endif + +union sockunion { + struct sockaddr_storage ss; + struct sockaddr sa; + struct sockaddr_dl sdl; +#ifdef INET + struct sockaddr_in sin; +#endif +#ifdef INET6 + struct sockaddr_in6 sin6; +#endif +}; +typedef union sockunion sockunion_t; + +#ifndef MIN +#define MIN(a, b) ((a) < (b) ? (a) : (b)) +#endif + +/* + * Internal: Map an IPv4 unicast address to an interface index. + * This is quite inefficient so it is recommended applications use + * the newer, more portable, protocol independent API. + */ +static uint32_t +__inaddr_to_index(in_addr_t ifaddr) +{ + struct ifaddrs *ifa; + struct ifaddrs *ifaddrs; + char *ifname; + int ifindex; + sockunion_t *psu; + + if (getifaddrs(&ifaddrs) < 0) + return (0); + + ifindex = 0; + ifname = NULL; + + /* + * Pass #1: Find the ifaddr entry corresponding to the + * supplied IPv4 address. We should really use the ifindex + * consistently for matches, however it is not available to + * us on this pass. + */ + for (ifa = ifaddrs; ifa != NULL; ifa = ifa->ifa_next) { + psu = (sockunion_t *)ifa->ifa_addr; + if (psu && psu->ss.ss_family == AF_INET && + psu->sin.sin_addr.s_addr == ifaddr) { + ifname = ifa->ifa_name; + break; + } + } + if (ifname == NULL) + goto out; + + /* + * Pass #2: Find the index of the interface matching the name + * we obtained from looking up the IPv4 ifaddr in pass #1. + * There must be a better way of doing this. + */ + for (ifa = ifaddrs; ifa != NULL; ifa = ifa->ifa_next) { + psu = (sockunion_t *)ifa->ifa_addr; + if (psu && psu->ss.ss_family == AF_LINK && + strcmp(ifa->ifa_name, ifname) == 0) { + ifindex = psu->sdl.sdl_index; + break; + } + } + assert(ifindex != 0); + +out: + freeifaddrs(ifaddrs); + return (ifindex); +} + +/* + * Set IPv4 source filter list in use on socket. + * + * Stubbed to setsourcefilter(). Performs conversion of structures which + * may be inefficient; applications are encouraged to use the + * protocol-independent API. + */ +int +setipv4sourcefilter(int s, struct in_addr interface, struct in_addr group, + uint32_t fmode, uint32_t numsrc, struct in_addr *slist) +{ +#ifdef INET + sockunion_t tmpgroup; + struct in_addr *pina; + sockunion_t *psu, *tmpslist; + int err; + size_t i; + uint32_t ifindex; + + assert(s != -1); + + tmpslist = NULL; + + if (!IN_MULTICAST(ntohl(group.s_addr)) || + (fmode != MCAST_INCLUDE && fmode != MCAST_EXCLUDE)) { + errno = EINVAL; + return (-1); + } + + ifindex = __inaddr_to_index(interface.s_addr); + if (ifindex == 0) { + errno = EADDRNOTAVAIL; + return (-1); + } + + memset(&tmpgroup, 0, sizeof(sockunion_t)); + tmpgroup.sin.sin_family = AF_INET; + tmpgroup.sin.sin_len = sizeof(struct sockaddr_in); + tmpgroup.sin.sin_addr = group; + + if (numsrc != 0 || slist != NULL) { + tmpslist = calloc(numsrc, sizeof(sockunion_t)); + if (tmpslist == NULL) { + errno = ENOMEM; + return (-1); + } + + pina = slist; + psu = tmpslist; + for (i = 0; i < numsrc; i++, pina++, psu++) { + psu->sin.sin_family = AF_INET; + psu->sin.sin_len = sizeof(struct sockaddr_in); + psu->sin.sin_addr = *pina; + } + } + + err = setsourcefilter(s, ifindex, (struct sockaddr *)&tmpgroup, + sizeof(struct sockaddr_in), fmode, numsrc, + (struct sockaddr_storage *)tmpslist); + + if (tmpslist != NULL) + free(tmpslist); + + return (err); +#else /* !INET */ + return (EAFNOSUPPORT); +#endif /* INET */ +} + +/* + * Get IPv4 source filter list in use on socket. + * + * Stubbed to getsourcefilter(). Performs conversion of structures which + * may be inefficient; applications are encouraged to use the + * protocol-independent API. + * An slist of NULL may be used for guessing the required buffer size. + */ +int +getipv4sourcefilter(int s, struct in_addr interface, struct in_addr group, + uint32_t *fmode, uint32_t *numsrc, struct in_addr *slist) +{ + sockunion_t *psu, *tmpslist; + sockunion_t tmpgroup; + struct in_addr *pina; + int err; + size_t i; + uint32_t ifindex, onumsrc; + + assert(s != -1); + assert(fmode != NULL); + assert(numsrc != NULL); + + onumsrc = *numsrc; + *numsrc = 0; + tmpslist = NULL; + + if (!IN_MULTICAST(ntohl(group.s_addr)) || + (onumsrc != 0 && slist == NULL)) { + errno = EINVAL; + return (-1); + } + + ifindex = __inaddr_to_index(interface.s_addr); + if (ifindex == 0) { + errno = EADDRNOTAVAIL; + return (-1); + } + + memset(&tmpgroup, 0, sizeof(sockunion_t)); + tmpgroup.sin.sin_family = AF_INET; + tmpgroup.sin.sin_len = sizeof(struct sockaddr_in); + tmpgroup.sin.sin_addr = group; + + if (onumsrc != 0 || slist != NULL) { + tmpslist = calloc(onumsrc, sizeof(sockunion_t)); + if (tmpslist == NULL) { + errno = ENOMEM; + return (-1); + } + } + + err = getsourcefilter(s, ifindex, (struct sockaddr *)&tmpgroup, + sizeof(struct sockaddr_in), fmode, numsrc, + (struct sockaddr_storage *)tmpslist); + + if (tmpslist != NULL && *numsrc != 0) { + pina = slist; + psu = tmpslist; + for (i = 0; i < MIN(onumsrc, *numsrc); i++, psu++) { + if (psu->ss.ss_family != AF_INET) + continue; + *pina++ = psu->sin.sin_addr; + } + free(tmpslist); + } + + return (err); +} + +/* + * Set protocol-independent source filter list in use on socket. + */ +int +setsourcefilter(int s, uint32_t interface, struct sockaddr *group, + socklen_t grouplen, uint32_t fmode, uint32_t numsrc, + struct sockaddr_storage *slist) +{ + struct __msfilterreq msfr; + sockunion_t *psu; + int level, optname; + + if (fmode != MCAST_INCLUDE && fmode != MCAST_EXCLUDE) { + errno = EINVAL; + return (-1); + } + + psu = (sockunion_t *)group; + switch (psu->ss.ss_family) { +#ifdef INET + case AF_INET: + if ((grouplen != sizeof(struct sockaddr_in) || + !IN_MULTICAST(ntohl(psu->sin.sin_addr.s_addr)))) { + errno = EINVAL; + return (-1); + } + level = IPPROTO_IP; + optname = IP_MSFILTER; + break; +#endif +#ifdef INET6 + case AF_INET6: + if (grouplen != sizeof(struct sockaddr_in6) || + !IN6_IS_ADDR_MULTICAST(&psu->sin6.sin6_addr)) { + errno = EINVAL; + return (-1); + } + level = IPPROTO_IPV6; + optname = IPV6_MSFILTER; + break; +#endif + default: + errno = EAFNOSUPPORT; + return (-1); + } + + memset(&msfr, 0, sizeof(msfr)); + msfr.msfr_ifindex = interface; + msfr.msfr_fmode = fmode; + msfr.msfr_nsrcs = numsrc; + memcpy(&msfr.msfr_group, &psu->ss, psu->ss.ss_len); + msfr.msfr_srcs = slist; /* pointer */ + + return (_setsockopt(s, level, optname, &msfr, sizeof(msfr))); +} + +/* + * Get protocol-independent source filter list in use on socket. + * An slist of NULL may be used for guessing the required buffer size. + */ +int +getsourcefilter(int s, uint32_t interface, struct sockaddr *group, + socklen_t grouplen, uint32_t *fmode, uint32_t *numsrc, + struct sockaddr_storage *slist) +{ + struct __msfilterreq msfr; + sockunion_t *psu; + int err, level, nsrcs, optlen, optname; + + if (interface == 0 || group == NULL || numsrc == NULL || + fmode == NULL) { + errno = EINVAL; + return (-1); + } + + nsrcs = *numsrc; + *numsrc = 0; + *fmode = 0; + + psu = (sockunion_t *)group; + switch (psu->ss.ss_family) { +#ifdef INET + case AF_INET: + if ((grouplen != sizeof(struct sockaddr_in) || + !IN_MULTICAST(ntohl(psu->sin.sin_addr.s_addr)))) { + errno = EINVAL; + return (-1); + } + level = IPPROTO_IP; + optname = IP_MSFILTER; + break; +#endif +#ifdef INET6 + case AF_INET6: + if (grouplen != sizeof(struct sockaddr_in6) || + !IN6_IS_ADDR_MULTICAST(&psu->sin6.sin6_addr)) { + errno = EINVAL; + return (-1); + } + level = IPPROTO_IPV6; + optname = IPV6_MSFILTER; + break; +#endif + default: + errno = EAFNOSUPPORT; + return (-1); + break; + } + + optlen = sizeof(struct __msfilterreq); + memset(&msfr, 0, optlen); + msfr.msfr_ifindex = interface; + msfr.msfr_fmode = 0; + msfr.msfr_nsrcs = nsrcs; + memcpy(&msfr.msfr_group, &psu->ss, psu->ss.ss_len); + + /* + * msfr_srcs is a pointer to a vector of sockaddr_storage. It + * may be NULL. The kernel will always return the total number + * of filter entries for the group in msfr.msfr_nsrcs. + */ + msfr.msfr_srcs = slist; + err = _getsockopt(s, level, optname, &msfr, &optlen); + if (err == 0) { + *numsrc = msfr.msfr_nsrcs; + *fmode = msfr.msfr_fmode; + } + + return (err); +} |
