diff options
Diffstat (limited to 'ext/socket/option.c')
| -rw-r--r-- | ext/socket/option.c | 143 |
1 files changed, 143 insertions, 0 deletions
diff --git a/ext/socket/option.c b/ext/socket/option.c index 6ebe6c73ef..01359bda2d 100644 --- a/ext/socket/option.c +++ b/ext/socket/option.c @@ -396,6 +396,133 @@ inspect_timeval_as_interval(int level, int optname, VALUE data, VALUE ret) } } +/* + * socket option for IPv4 multicast is bit confusing. + * + * IP Multicast is implemented by Steve Deering at first: + * IP Multicast Extensions for 4.3BSD UNIX and related systems + * (MULTICAST 1.2 Release) + * http://www.kohala.com/start/mcast.api.txt + * + * There are 3 socket options which takes a struct. + * + * IP_MULTICAST_IF: struct in_addr + * IP_ADD_MEMBERSHIP: struct ip_mreq + * IP_DROP_MEMBERSHIP: struct ip_mreq + * + * But they uses an IP address to specify an interface. + * This means the API cannot specify an unnumbered interface. + * + * Linux 2.4 introduces struct ip_mreqn to fix this problem. + * struct ip_mreqn has imr_ifindex field to specify interface index. + * + * IP_MULTICAST_IF: struct ip_mreqn + * IP_ADD_MEMBERSHIP: struct ip_mreqn + * IP_DROP_MEMBERSHIP: struct ip_mreqn + * + * FreeBSD 7 obtained struct ip_mreqn for IP_MULTICAST_IF. + * http://www.FreeBSD.org/cgi/cvsweb.cgi/src/sys/netinet/in.h.diff?r1=1.99;r2=1.100 + * + * Another hackish workaround is "RFC 1724 hack". + * RFC 1724 section 3.3 suggests unnumbered interfaces + * specified by pseudo address 0.0.0.0/8. + * NetBSD 4 documented it. + * http://cvsweb.netbsd.org/cgi-bin/cvsweb.cgi/src/share/man/man4/ip.4.diff?r1=1.16&r2=1.17 + * + * RFC 1724 hack is not supported by Socket::Option#inspect because + * it is not distinguishable by the size. + */ + +#if defined(IPPROTO_IP) && defined(HAVE_TYPE_STRUCT_IP_MREQ) /* 4.4BSD, GNU/Linux */ +static int +inspect_ipv4_mreq(int level, int optname, VALUE data, VALUE ret) +{ + if (RSTRING_LEN(data) == sizeof(struct ip_mreq)) { + struct ip_mreq s; + char addrbuf[INET_ADDRSTRLEN]; + memcpy((char*)&s, RSTRING_PTR(data), sizeof(s)); + if (inet_ntop(AF_INET, &s.imr_multiaddr, addrbuf, (socklen_t)sizeof(addrbuf)) == NULL) + rb_str_cat2(ret, " invalid-address"); + else + rb_str_catf(ret, " %s", addrbuf); + if (inet_ntop(AF_INET, &s.imr_interface, addrbuf, (socklen_t)sizeof(addrbuf)) == NULL) + rb_str_catf(ret, " invalid-address"); + else + rb_str_catf(ret, " %s", addrbuf); + return 1; + } + else { + return 0; + } +} +#endif + +#if defined(IPPROTO_IP) && defined(HAVE_TYPE_STRUCT_IP_MREQN) /* GNU/Linux, FreeBSD 7 */ +static int +inspect_ipv4_mreqn(int level, int optname, VALUE data, VALUE ret) +{ + if (RSTRING_LEN(data) == sizeof(struct ip_mreqn)) { + struct ip_mreqn s; + char addrbuf[INET_ADDRSTRLEN], ifbuf[IFNAMSIZ]; + memcpy((char*)&s, RSTRING_PTR(data), sizeof(s)); + if (inet_ntop(AF_INET, &s.imr_multiaddr, addrbuf, (socklen_t)sizeof(addrbuf)) == NULL) + rb_str_cat2(ret, " invalid-address"); + else + rb_str_catf(ret, " %s", addrbuf); + if (inet_ntop(AF_INET, &s.imr_address, addrbuf, (socklen_t)sizeof(addrbuf)) == NULL) + rb_str_catf(ret, " invalid-address"); + else + rb_str_catf(ret, " %s", addrbuf); + if (if_indextoname(s.imr_ifindex, ifbuf) == NULL) + rb_str_catf(ret, " ifindex:%d", s.imr_ifindex); + else + rb_str_catf(ret, " %s", ifbuf); + return 1; + } + else { + return 0; + } +} +#endif + +#if defined(IPPROTO_IP) && defined(HAVE_TYPE_STRUCT_IP_MREQ) /* 4.4BSD, GNU/Linux */ +static int +inspect_ipv4_add_drop_membership(int level, int optname, VALUE data, VALUE ret) +{ + if (RSTRING_LEN(data) == sizeof(struct ip_mreq)) + return inspect_ipv4_mreq(level, optname, data, ret); +# if defined(HAVE_TYPE_STRUCT_IP_MREQN) + else if (RSTRING_LEN(data) == sizeof(struct ip_mreqn)) + return inspect_ipv4_mreqn(level, optname, data, ret); +# endif + else + return 0; +} +#endif + +#if defined(IPPROTO_IP) && defined(IP_MULTICAST_IF) /* 4.4BSD, GNU/Linux */ +static int +inspect_ipv4_multicast_if(int level, int optname, VALUE data, VALUE ret) +{ + if (RSTRING_LEN(data) == sizeof(struct in_addr)) { + struct in_addr s; + char addrbuf[INET_ADDRSTRLEN]; + memcpy((char*)&s, RSTRING_PTR(data), sizeof(s)); + if (inet_ntop(AF_INET, &s, addrbuf, (socklen_t)sizeof(addrbuf)) == NULL) + rb_str_cat2(ret, " invalid-address"); + else + rb_str_catf(ret, " %s", addrbuf); + return 1; + } + else if (RSTRING_LEN(data) == sizeof(struct ip_mreqn)) { + return inspect_ipv4_mreqn(level, optname, data, ret); + } + else { + return 0; + } +} +#endif + #if defined(IPPROTO_IPV6) && defined(HAVE_TYPE_STRUCT_IPV6_MREQ) /* POSIX, RFC 3493 */ static int inspect_ipv6_mreq(int level, int optname, VALUE data, VALUE ret) @@ -611,6 +738,22 @@ sockopt_inspect(VALUE self) case AF_INET6: #endif switch (level) { +# if defined(IPPROTO_IP) + case IPPROTO_IP: + switch (optname) { +# if defined(IP_MULTICAST_IF) /* 4.4BSD, GNU/Linux */ + case IP_MULTICAST_IF: inspected = inspect_ipv4_multicast_if(level, optname, data, ret); break; +# endif +# if defined(IP_ADD_MEMBERSHIP) /* 4.4BSD, GNU/Linux */ + case IP_ADD_MEMBERSHIP: inspected = inspect_ipv4_add_drop_membership(level, optname, data, ret); break; +# endif +# if defined(IP_DROP_MEMBERSHIP) /* 4.4BSD, GNU/Linux */ + case IP_DROP_MEMBERSHIP: inspected = inspect_ipv4_add_drop_membership(level, optname, data, ret); break; +# endif + } + break; +# endif + # if defined(IPPROTO_IPV6) case IPPROTO_IPV6: switch (optname) { |