From 6f3914d5a3269c00e70506bd95f816fef6b635ce Mon Sep 17 00:00:00 2001 From: Ulrich Drepper Date: Mon, 12 Nov 2007 23:55:58 +0000 Subject: [PATCH] * include/ifaddrs.c (struct in6addrinfo): Add prefixlen field. * sysdeps/unix/sysv/linux/check_pf.c (make_request): Always return list of interfaces. Also store prefix length. * sysdeps/posix/getaddrinfo.c (sort_result): Add prefixlen element. (rfc3484_sort): In rule 9, for IPv4 addresses count only matching prefix if source and destination address are in the same subnet. (getaddrinfo): Always call __check_pf. Fill in prefixlen field. Always look for matching record in in6ai list. Correct source_addr_len value for IPv6->IPv4 converted records. --- ChangeLog | 12 +++ sysdeps/posix/getaddrinfo.c | 167 ++++++++++++++++------------- sysdeps/unix/sysv/linux/check_pf.c | 123 +++++++++------------ 3 files changed, 154 insertions(+), 148 deletions(-) diff --git a/ChangeLog b/ChangeLog index 37cda4cb9f..b28845df41 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,15 @@ +2007-11-12 Ulrich Drepper + + * include/ifaddrs.c (struct in6addrinfo): Add prefixlen field. + * sysdeps/unix/sysv/linux/check_pf.c (make_request): Always return + list of interfaces. Also store prefix length. + * sysdeps/posix/getaddrinfo.c (sort_result): Add prefixlen element. + (rfc3484_sort): In rule 9, for IPv4 addresses count only matching + prefix if source and destination address are in the same subnet. + (getaddrinfo): Always call __check_pf. Fill in prefixlen field. + Always look for matching record in in6ai list. + Correct source_addr_len value for IPv6->IPv4 converted records. + 2007-11-11 Roland McGrath * include/kernel-features.h: New file. diff --git a/sysdeps/posix/getaddrinfo.c b/sysdeps/posix/getaddrinfo.c index 8cf9c6bdfe..57970b4363 100644 --- a/sysdeps/posix/getaddrinfo.c +++ b/sysdeps/posix/getaddrinfo.c @@ -1006,6 +1006,7 @@ struct sort_result uint8_t source_addr_len; bool got_source_addr; uint8_t source_addr_flags; + uint8_t prefixlen; }; @@ -1223,7 +1224,7 @@ static int fls (uint32_t a) { uint32_t mask; - int n = 0; + int n; for (n = 0, mask = 1 << 31; n < 32; mask >>= 1, ++n) if ((a & mask) != 0) break; @@ -1350,20 +1351,31 @@ rfc3484_sort (const void *p1, const void *p2) assert (a1->source_addr.ss_family == PF_INET); assert (a2->source_addr.ss_family == PF_INET); - struct sockaddr_in *in1_dst; - struct sockaddr_in *in1_src; - struct sockaddr_in *in2_dst; - struct sockaddr_in *in2_src; + /* Outside of subnets, as defined by the network masks, + common address prefixes for IPv4 addresses make no sense. + So, define a non-zero value only if source and + destination address are on the same subnet. */ + struct sockaddr_in *in1_dst + = (struct sockaddr_in *) a1->dest_addr->ai_addr; + in_addr_t in1_dst_addr = ntohl (in1_dst->sin_addr.s_addr); + struct sockaddr_in *in1_src + = (struct sockaddr_in *) &a1->source_addr; + in_addr_t in1_src_addr = ntohl (in1_src->sin_addr.s_addr); + in_addr_t netmask1 = 0xffffffffu << (32 - a1->prefixlen); - in1_dst = (struct sockaddr_in *) a1->dest_addr->ai_addr; - in1_src = (struct sockaddr_in *) &a1->source_addr; - in2_dst = (struct sockaddr_in *) a2->dest_addr->ai_addr; - in2_src = (struct sockaddr_in *) &a2->source_addr; + if ((in1_src_addr & netmask1) == (in1_dst_addr & netmask1)) + bit1 = fls (in1_dst_addr ^ in1_src_addr); - bit1 = fls (ntohl (in1_dst->sin_addr.s_addr - ^ in1_src->sin_addr.s_addr)); - bit2 = fls (ntohl (in2_dst->sin_addr.s_addr - ^ in2_src->sin_addr.s_addr)); + struct sockaddr_in *in2_dst + = (struct sockaddr_in *) a2->dest_addr->ai_addr; + in_addr_t in2_dst_addr = ntohl (in2_dst->sin_addr.s_addr); + struct sockaddr_in *in2_src + = (struct sockaddr_in *) &a2->source_addr; + in_addr_t in2_src_addr = ntohl (in2_src->sin_addr.s_addr); + in_addr_t netmask2 = 0xffffffffu << (32 - a2->prefixlen); + + if ((in2_src_addr & netmask2) == (in2_dst_addr & netmask2)) + bit2 = fls (in2_dst_addr ^ in2_src_addr); } else if (a1->dest_addr->ai_family == PF_INET6) { @@ -1799,63 +1811,42 @@ getaddrinfo (const char *name, const char *service, int sockfd = -1; pid_t nl_pid; #endif - /* We might need information about what kind of interfaces are available. - But even if AI_ADDRCONFIG is not used, if the user requested IPv6 - addresses we have to know whether an address is deprecated or - temporary. */ - if ((hints->ai_flags & AI_ADDRCONFIG) || hints->ai_family == PF_UNSPEC - || hints->ai_family == PF_INET6) - { - /* Determine whether we have IPv4 or IPv6 interfaces or both. We - cannot cache the results since new interfaces could be added at - any time. */ - __check_pf (&seen_ipv4, &seen_ipv6, &in6ai, &in6ailen); + /* We might need information about what interfaces are available. + Also determine whether we have IPv4 or IPv6 interfaces or both. We + cannot cache the results since new interfaces could be added at + any time. */ + __check_pf (&seen_ipv4, &seen_ipv6, &in6ai, &in6ailen); #ifdef HAVE_NETLINK_ROUTE - if (! __no_netlink_support) + if (! __no_netlink_support) + { + sockfd = __socket (PF_NETLINK, SOCK_RAW, NETLINK_ROUTE); + + struct sockaddr_nl nladdr; + memset (&nladdr, '\0', sizeof (nladdr)); + nladdr.nl_family = AF_NETLINK; + + socklen_t addr_len = sizeof (nladdr); + + if (sockfd >= 0 + && __bind (fd, (struct sockaddr *) &nladdr, sizeof (nladdr)) == 0 + && __getsockname (sockfd, (struct sockaddr *) &nladdr, + &addr_len) == 0 + && make_request (sockfd, nladdr.nl_pid, &seen_ipv4, &seen_ipv6, + in6ai, in6ailen) == 0) { - sockfd = __socket (PF_NETLINK, SOCK_RAW, NETLINK_ROUTE); - - struct sockaddr_nl nladdr; - memset (&nladdr, '\0', sizeof (nladdr)); - nladdr.nl_family = AF_NETLINK; - - socklen_t addr_len = sizeof (nladdr); - - if (sockfd >= 0 - && __bind (fd, (struct sockaddr *) &nladdr, sizeof (nladdr)) == 0 - && __getsockname (sockfd, (struct sockaddr *) &nladdr, - &addr_len) == 0 - && make_request (sockfd, nladdr.nl_pid, &seen_ipv4, &seen_ipv6, - in6ai, in6ailen) == 0) - { - /* It worked. */ - nl_pid = nladdr.nl_pid; - goto got_netlink_socket; - } - - if (sockfd >= 0) - close_not_cancel_no_status (sockfd); - -#if __ASSUME_NETLINK_SUPPORT == 0 - /* Remember that there is no netlink support. */ - if (errno != EMFILE && errno != ENFILE) - __no_netlink_support = 1; -#else - else - { - if (errno != EMFILE && errno != ENFILE) - sockfd = -2; - - /* We cannot determine what interfaces are available. Be - pessimistic. */ - seen_ipv4 = true; - seen_ipv6 = true; - return; - } -#endif + /* It worked. */ + nl_pid = nladdr.nl_pid; + goto got_netlink_socket; } -#endif + + if (sockfd >= 0) + close_not_cancel_no_status (sockfd); + + /* Remember that there is no netlink support. */ + if (errno != EMFILE && errno != ENFILE) + __no_netlink_support = 1; } +#endif #ifdef HAVE_NETLINK_ROUTE got_netlink_socket: @@ -1958,7 +1949,6 @@ getaddrinfo (const char *name, const char *service, for (i = 0, q = p; q != NULL; ++i, last = q, q = q->ai_next) { results[i].dest_addr = q; - results[i].got_source_addr = false; results[i].service_order = i; /* If we just looked up the address for a different @@ -1971,10 +1961,13 @@ getaddrinfo (const char *name, const char *service, results[i].source_addr_len = results[i - 1].source_addr_len; results[i].got_source_addr = results[i - 1].got_source_addr; results[i].source_addr_flags = results[i - 1].source_addr_flags; + results[i].prefixlen = results[i - 1].prefixlen; } else { + results[i].got_source_addr = false; results[i].source_addr_flags = 0; + results[i].prefixlen = 0; /* We overwrite the type with SOCK_DGRAM since we do not want connect() to connect to the other side. If we @@ -2005,22 +1998,39 @@ getaddrinfo (const char *name, const char *service, results[i].source_addr_len = sl; results[i].got_source_addr = true; - if (q->ai_family == AF_INET6 && in6ai != NULL) + if (in6ai != NULL) { /* See whether the source address is on the list of deprecated or temporary addresses. */ struct in6addrinfo tmp; - struct sockaddr_in6 *sin6p - = (struct sockaddr_in6 *) &results[i].source_addr; - memcpy (tmp.addr, &sin6p->sin6_addr, IN6ADDRSZ); + + if (q->ai_family == AF_INET && af == AF_INET) + { + struct sockaddr_in *sinp + = (struct sockaddr_in *) &results[i].source_addr; + tmp.addr[0] = 0; + tmp.addr[1] = 0; + tmp.addr[2] = htonl (0xffff); + tmp.addr[3] = sinp->sin_addr.s_addr; + } + else + { + struct sockaddr_in6 *sin6p + = (struct sockaddr_in6 *) &results[i].source_addr; + memcpy (tmp.addr, &sin6p->sin6_addr, IN6ADDRSZ); + } struct in6addrinfo *found = bsearch (&tmp, in6ai, in6ailen, sizeof (*in6ai), in6aicmp); if (found != NULL) - results[i].source_addr_flags = found->flags; + { + results[i].source_addr_flags = found->flags; + results[i].prefixlen = found->prefixlen; + } } - else if (q->ai_family == AF_INET && af == AF_INET6) + + if (q->ai_family == AF_INET && af == AF_INET6) { /* We have to convert the address. The socket is IPv6 and the request is for IPv4. */ @@ -2029,10 +2039,17 @@ getaddrinfo (const char *name, const char *service, struct sockaddr_in *sin = (struct sockaddr_in *) &results[i].source_addr; assert (IN6_IS_ADDR_V4MAPPED (sin6->sin6_addr.s6_addr32)); + sin->sin_family = AF_INET; + /* We do not have to initialize sin_port since this + fields has the same position and size in the IPv6 + structure. */ + assert (offsetof (struct sockaddr_in, sin_port) + == offsetof (struct sockaddr_in6, sin6_port)); + assert (sizeof (sin->sin_port) + == sizeof (sin6->sin6_port)); memcpy (&sin->sin_addr, &sin6->sin6_addr.s6_addr32[3], INADDRSZ); - results[i].source_addr_len = INADDRSZ; - sin->sin_family = AF_INET; + results[i].source_addr_len = sizeof (struct sockaddr_in); } } else if (errno == EAFNOSUPPORT && af == AF_INET6 diff --git a/sysdeps/unix/sysv/linux/check_pf.c b/sysdeps/unix/sysv/linux/check_pf.c index df7cbb1897..532e1d923d 100644 --- a/sysdeps/unix/sysv/linux/check_pf.c +++ b/sysdeps/unix/sysv/linux/check_pf.c @@ -145,92 +145,69 @@ make_request (int fd, pid_t pid, bool *seen_ipv4, bool *seen_ipv6, struct rtattr *rta = IFA_RTA (ifam); size_t len = nlmh->nlmsg_len - NLMSG_LENGTH (sizeof (*ifam)); - switch (ifam->ifa_family) + if (ifam->ifa_family != AF_INET + && ifam->ifa_family != AF_INET6) + continue; + + const void *local = NULL; + const void *address = NULL; + while (RTA_OK (rta, len)) { - const void *local; - const void *address; - - case AF_INET: - local = NULL; - address = NULL; - while (RTA_OK (rta, len)) + switch (rta->rta_type) { - switch (rta->rta_type) - { - case IFA_LOCAL: - local = RTA_DATA (rta); - break; + case IFA_LOCAL: + local = RTA_DATA (rta); + break; - case IFA_ADDRESS: - address = RTA_DATA (rta); - goto out_v4; - } - - rta = RTA_NEXT (rta, len); + case IFA_ADDRESS: + address = RTA_DATA (rta); + goto out; } - if (local != NULL) + rta = RTA_NEXT (rta, len); + } + + if (local != NULL) + { + address = local; + out: + if (ifam->ifa_family != AF_INET) { - out_v4: - if (*(const in_addr_t *) (address ?: local) + if (*(const in_addr_t *) address != htonl (INADDR_LOOPBACK)) *seen_ipv4 = true; } - break; - - case AF_INET6: - local = NULL; - address = NULL; - while (RTA_OK (rta, len)) + else { - switch (rta->rta_type) - { - case IFA_LOCAL: - local = RTA_DATA (rta); - break; - - case IFA_ADDRESS: - address = RTA_DATA (rta); - goto out_v6; - } - - rta = RTA_NEXT (rta, len); - } - - if (local != NULL) - { - out_v6: - if (!IN6_IS_ADDR_LOOPBACK (address ?: local)) + if (!IN6_IS_ADDR_LOOPBACK (address)) *seen_ipv6 = true; } - - if (ifam->ifa_flags & (IFA_F_DEPRECATED - | IFA_F_TEMPORARY - | IFA_F_HOMEADDRESS - | IFA_F_OPTIMISTIC)) - { - struct in6ailist *newp = alloca (sizeof (*newp)); - newp->info.flags = (((ifam->ifa_flags - & (IFA_F_DEPRECATED - | IFA_F_OPTIMISTIC)) - ? in6ai_deprecated : 0) - | ((ifam->ifa_flags - & IFA_F_TEMPORARY) - ? in6ai_temporary : 0) - | ((ifam->ifa_flags - & IFA_F_HOMEADDRESS) - ? in6ai_homeaddress : 0)); - memcpy (newp->info.addr, address ?: local, - sizeof (newp->info.addr)); - newp->next = in6ailist; - in6ailist = newp; - ++in6ailistlen; - } - break; - default: - /* Ignore. */ - break; } + + struct in6ailist *newp = alloca (sizeof (*newp)); + newp->info.flags = (((ifam->ifa_flags + & (IFA_F_DEPRECATED + | IFA_F_OPTIMISTIC)) + ? in6ai_deprecated : 0) + | ((ifam->ifa_flags + & IFA_F_TEMPORARY) + ? in6ai_temporary : 0) + | ((ifam->ifa_flags + & IFA_F_HOMEADDRESS) + ? in6ai_homeaddress : 0)); + newp->info.prefixlen = ifam->ifa_prefixlen; + if (ifam->ifa_family == AF_INET) + { + newp->info.addr[0] = 0; + newp->info.addr[1] = 0; + newp->info.addr[2] = htonl (0xffff); + newp->info.addr[3] = *(const in_addr_t *) address; + } + else + memcpy (newp->info.addr, address, sizeof (newp->info.addr)); + newp->next = in6ailist; + in6ailist = newp; + ++in6ailistlen; } else if (nlmh->nlmsg_type == NLMSG_DONE) /* We found the end, leave the loop. */