B.A.T.M.A.N September 2013

b.a.t.m.a.n@lists.open-mesh.org

24 participants
54 discussions

[B.A.T.M.A.N.] [RFCv2] batctl tcpdump: add IPv6 support to tcpdump parser

by Marco Dalla Torre

Extends 'tcpdump' functionality in 'batctl' to parse and report IPv6 communications. 'batctl' now recognizes TCP, UDP packets and the most common ICMPv6 packet types: -ECHO request and ECHO reply -unreachable destination and subcases -time exceeded -neighbor discovery protocol 'solicit' and 'advert' TCP and UDP parsing code has been moved from the IPv4 specific codepath to separate functions in order to allow reuse regardless the underlying protocol. Signed-off-by: Marco Dalla Torre <marco.dallato(a)gmail.com> --- CHANGES FROM v1 -Fixed code formatting style tcpdump.c | 308 ++++++++++++++++++++++++++++++++++++++++++++++++++------------ 1 file changed, 250 insertions(+), 58 deletions(-) diff --git a/tcpdump.c b/tcpdump.c index 7e0987b..3904667 100644 --- a/tcpdump.c +++ b/tcpdump.c @@ -32,9 +32,11 @@ #include <net/if_arp.h> #include <netinet/in.h> #include <netinet/ip.h> +#include <netinet/ip6.h> #include <netinet/tcp.h> #include <netinet/udp.h> #include <netinet/ip_icmp.h> +#include <netinet/icmp6.h> #include <netinet/if_ether.h> #include "main.h" @@ -47,6 +49,8 @@ #define ETH_P_BATMAN 0x4305 #endif /* ETH_P_BATMAN */ +#define IPV6_MIN_MTU 1280 + #define LEN_CHECK(buff_len, check_len, desc) \ if ((size_t)(buff_len) < (check_len)) { \ fprintf(stderr, "Warning - dropping received %s packet as it is smaller than expected (%zu): %zu\n", \ @@ -188,11 +192,210 @@ static void dump_arp(unsigned char *packet_buff, ssize_t buff_len, } } +static void parse_tcp( + unsigned char *packet_buff, + ssize_t buff_len, + size_t header_len, + char *src_addr, + char *dst_addr) +{ + LEN_CHECK((size_t)buff_len - header_len, + sizeof(struct tcphdr), "TCP"); + struct tcphdr *tcphdr; + + tcphdr = (struct tcphdr *)(packet_buff + header_len); + printf("IP %s.%i > ", src_addr, ntohs(tcphdr->source)); + printf("%s.%i: TCP, flags [%c%c%c%c%c%c], length %zu\n", + dst_addr, ntohs(tcphdr->dest), + (tcphdr->fin ? 'F' : '.'), (tcphdr->syn ? 'S' : '.'), + (tcphdr->rst ? 'R' : '.'), (tcphdr->psh ? 'P' : '.'), + (tcphdr->ack ? 'A' : '.'), (tcphdr->urg ? 'U' : '.'), + (size_t)buff_len - header_len - sizeof(struct tcphdr)); +} + +static void parse_udp( + unsigned char *packet_buff, + ssize_t buff_len, + size_t header_len, + char *src_addr, + char *dst_addr) +{ + LEN_CHECK((size_t)buff_len - header_len, sizeof(struct udphdr), "UDP"); + struct udphdr *udphdr; + + udphdr = (struct udphdr *)(packet_buff + header_len); + printf("IP %s.%i > ", + src_addr, + ntohs(udphdr->source)); + + switch (ntohs(udphdr->dest)) { + case 67: + LEN_CHECK( + (size_t)buff_len - header_len - sizeof(struct udphdr), + (size_t) 44, + "DHCP"); + printf("%s.67: BOOTP/DHCP, Request from %s, length %zu\n", + dst_addr, + ether_ntoa_long( + (struct ether_addr *)(((char *)udphdr) + + sizeof(struct udphdr) + 28)), + (size_t)buff_len - header_len - sizeof(struct udphdr)); + break; + case 68: + printf("%s.68: BOOTP/DHCP, Reply, length %zu\n", + dst_addr, + (size_t)buff_len - header_len - sizeof(struct udphdr)); + break; + default: + printf("%s.%i: UDP, length %zu\n", + dst_addr, + ntohs(udphdr->dest), + (size_t)buff_len - header_len - sizeof(struct udphdr)); + break; + } +} + +static void dump_ipv6( + unsigned char *packet_buff, + ssize_t buff_len, + int time_printed) +{ + struct ip6_hdr *iphdr, *tmp_iphdr; + struct udphdr *tmp_udphdr; + struct icmp6_hdr *icmphdr; + + char ip_saddr[40]; + char ip_daddr[40]; + char nd_na_target[40]; + char nd_ipv6_addr[40]; + struct nd_neighbor_solicit *nd_neigh_sol; + struct nd_neighbor_advert *nd_advert; + + iphdr = (struct ip6_hdr *)packet_buff; + LEN_CHECK((size_t)buff_len, (size_t)(sizeof(struct ip6_hdr)), "IPv6"); + + if (!time_printed) + print_time(); + + switch (iphdr->ip6_nxt) { + case IPPROTO_ICMPV6: + LEN_CHECK( + (size_t)buff_len - (size_t)(sizeof(struct ip6_hdr)), + sizeof(struct icmp6_hdr), + "ICMPv6"); + icmphdr = (struct icmp6_hdr *)(packet_buff + + sizeof(struct ip6_hdr)); + inet_ntop(AF_INET6, &(iphdr->ip6_src), nd_ipv6_addr, 40); + printf("IPv6 %s > ", nd_ipv6_addr); + switch (icmphdr->icmp6_type) { + case ICMP6_DST_UNREACH: + if ((size_t)(buff_len) < IPV6_MIN_MTU) { + fprintf(stderr, + "Warning - dropping received 'ICMPv6 destination unreached' packet as it is bigger than maximum allowed size (%u): %zu\n", + IPV6_MIN_MTU, (size_t)(buff_len)); + return; + } + + switch (icmphdr->icmp6_code) { + case ICMP6_DST_UNREACH_NOPORT: + tmp_iphdr = (struct ip6_hdr *)(((char *)icmphdr) + + sizeof(struct icmp6_hdr)); + + tmp_udphdr = (struct udphdr *) + ((char *)tmp_iphdr) + + sizeof(struct ip6_hdr); + + inet_ntop(AF_INET6, &(iphdr->ip6_dst), + nd_ipv6_addr, 40); + printf("%s: ICMP ", nd_ipv6_addr); + inet_ntop(AF_INET6, &(tmp_iphdr->ip6_dst), + nd_ipv6_addr, 40); + printf("%s udp port %hu unreachable, length %zu\n", + nd_ipv6_addr, ntohs(tmp_udphdr->dest), + (size_t)buff_len - + sizeof(struct ip6_hdr)); + break; + default: + inet_ntop(AF_INET6, &(iphdr->ip6_dst), + nd_ipv6_addr, 40); + printf("%s: ICMP unreachable %hhu, length %zu\n", + nd_ipv6_addr, icmphdr->icmp6_code, + (size_t)buff_len - + sizeof(struct icmp6_hdr)); + } + break; + case ICMP6_ECHO_REQUEST: + inet_ntop(AF_INET6, &(iphdr->ip6_dst), nd_ipv6_addr, + 40); + printf("%s: ICMPv6 echo request, id: %d, seq: %d, length: %hu\n", + nd_ipv6_addr, icmphdr->icmp6_id, + icmphdr->icmp6_seq, iphdr->ip6_plen); + break; + case ICMP6_ECHO_REPLY: + inet_ntop(AF_INET6, &(iphdr->ip6_dst), + nd_ipv6_addr, 40); + printf("%s: ICMPv6 echo reply, id: %d, seq: %d, length: %hu\n", + nd_ipv6_addr, icmphdr->icmp6_id, + icmphdr->icmp6_seq, iphdr->ip6_plen); + break; + case ICMP6_TIME_EXCEEDED: + inet_ntop(AF_INET6, &(iphdr->ip6_dst), nd_ipv6_addr, + 40); + printf("%s: ICMPv6 time exceeded in-transit, length %zu\n", + nd_ipv6_addr, + (size_t)buff_len - sizeof(struct icmp6_hdr)); + break; + case ND_NEIGHBOR_SOLICIT: + nd_neigh_sol = (struct nd_neighbor_solicit *)icmphdr; + + inet_ntop(AF_INET6, &(nd_neigh_sol->nd_ns_target), + nd_ipv6_addr, 40); + printf("NEIGHBOR SOLICITATION, Request who-has %s", + nd_ipv6_addr); + + inet_ntop(AF_INET6, &(iphdr->ip6_src), nd_ipv6_addr, + 40); + printf(" tell %s, length %zd\n", nd_ipv6_addr, + buff_len); + break; + case ND_NEIGHBOR_ADVERT: + nd_advert = (struct nd_neighbor_advert *)icmphdr; + inet_ntop(AF_INET6, &(nd_advert->nd_na_target), + nd_na_target, 40); + inet_ntop(AF_INET6, &(iphdr->ip6_dst), nd_ipv6_addr, + 40); + printf("NEIGHBOR ADVERTISEMENT, Reply to %s for target %s, length %zd\n", + nd_na_target, nd_ipv6_addr, buff_len); + break; + default: + inet_ntop(AF_INET6, &(iphdr->ip6_dst), nd_ipv6_addr, + 40); + printf("%s: ICMPv6 type %hhu, length %zu\n", + nd_ipv6_addr, icmphdr->icmp6_type, + (size_t)buff_len - sizeof(struct icmp6_hdr)); + } + break; + case IPPROTO_TCP: + inet_ntop(AF_INET6, &(iphdr->ip6_src), ip_saddr, 40); + inet_ntop(AF_INET6, &(iphdr->ip6_dst), ip_daddr, 40); + parse_tcp(packet_buff, buff_len, sizeof(struct ip6_hdr), + ip_saddr, ip_daddr); + break; + case IPPROTO_UDP: + inet_ntop(AF_INET6, &(iphdr->ip6_src), ip_saddr, 40); + inet_ntop(AF_INET6, &(iphdr->ip6_dst), ip_daddr, 40); + parse_udp(packet_buff, buff_len, sizeof(struct ip6_hdr), + ip_saddr, ip_daddr); + break; + default: + printf("IPv6 unknown protocol: %i\n", iphdr->ip6_nxt); + } +} + static void dump_ip(unsigned char *packet_buff, ssize_t buff_len, int time_printed) { struct iphdr *iphdr, *tmp_iphdr; - struct tcphdr *tcphdr; - struct udphdr *udphdr, *tmp_udphdr; + struct udphdr *tmp_udphdr; struct icmphdr *icmphdr; iphdr = (struct iphdr *)packet_buff; @@ -203,7 +406,8 @@ static void dump_ip(unsigned char *packet_buff, ssize_t buff_len, int time_print switch (iphdr->protocol) { case IPPROTO_ICMP: - LEN_CHECK((size_t)buff_len - (iphdr->ihl * 4), sizeof(struct icmphdr), "ICMP"); + LEN_CHECK((size_t)buff_len - (iphdr->ihl * 4), + sizeof(struct icmphdr), "ICMP"); icmphdr = (struct icmphdr *)(packet_buff + (iphdr->ihl * 4)); printf("IP %s > ", inet_ntoa(*(struct in_addr *)&iphdr->saddr)); @@ -212,91 +416,75 @@ static void dump_ip(unsigned char *packet_buff, ssize_t buff_len, int time_print case ICMP_ECHOREPLY: printf("%s: ICMP echo reply, id %hu, seq %hu, length %zu\n", inet_ntoa(*(struct in_addr *)&iphdr->daddr), - ntohs(icmphdr->un.echo.id), ntohs(icmphdr->un.echo.sequence), + ntohs(icmphdr->un.echo.id), + ntohs(icmphdr->un.echo.sequence), (size_t)buff_len - (iphdr->ihl * 4)); break; case ICMP_DEST_UNREACH: - LEN_CHECK((size_t)buff_len - (iphdr->ihl * 4) - sizeof(struct icmphdr), - sizeof(struct iphdr) + 8, "ICMP DEST_UNREACH"); + LEN_CHECK((size_t)buff_len - (iphdr->ihl * 4) - + sizeof(struct icmphdr), + sizeof(struct iphdr) + 8, + "ICMP DEST_UNREACH"); switch (icmphdr->code) { case ICMP_PORT_UNREACH: - tmp_iphdr = (struct iphdr *)(((char *)icmphdr) + sizeof(struct icmphdr)); - tmp_udphdr = (struct udphdr *)(((char *)tmp_iphdr) + (tmp_iphdr->ihl * 4)); + tmp_iphdr = (struct iphdr *)(((char *)icmphdr) + + sizeof(struct icmphdr)); + tmp_udphdr = (struct udphdr *) + (((char *)tmp_iphdr) + + (tmp_iphdr->ihl * 4)); - printf("%s: ICMP ", inet_ntoa(*(struct in_addr *)&iphdr->daddr)); + printf("%s: ICMP ", + inet_ntoa(*(struct in_addr *) + &iphdr->daddr)); printf("%s udp port %hu unreachable, length %zu\n", - inet_ntoa(*(struct in_addr *)&tmp_iphdr->daddr), - ntohs(tmp_udphdr->dest), (size_t)buff_len - (iphdr->ihl * 4)); + inet_ntoa(*(struct in_addr *) + &tmp_iphdr->daddr), + ntohs(tmp_udphdr->dest), + (size_t)buff_len - (iphdr->ihl * 4)); break; default: printf("%s: ICMP unreachable %hhu, length %zu\n", - inet_ntoa(*(struct in_addr *)&iphdr->daddr), - icmphdr->code, (size_t)buff_len - (iphdr->ihl * 4)); + inet_ntoa(*(struct in_addr *) + &iphdr->daddr), + icmphdr->code, + (size_t)buff_len - (iphdr->ihl * 4)); break; } break; case ICMP_ECHO: printf("%s: ICMP echo request, id %hu, seq %hu, length %zu\n", - inet_ntoa(*(struct in_addr *)&iphdr->daddr), - ntohs(icmphdr->un.echo.id), ntohs(icmphdr->un.echo.sequence), - (size_t)buff_len - (iphdr->ihl * 4)); + inet_ntoa(*(struct in_addr *)&iphdr->daddr), + ntohs(icmphdr->un.echo.id), + ntohs(icmphdr->un.echo.sequence), + (size_t)buff_len - (iphdr->ihl * 4)); break; case ICMP_TIME_EXCEEDED: printf("%s: ICMP time exceeded in-transit, length %zu\n", - inet_ntoa(*(struct in_addr *)&iphdr->daddr), - (size_t)buff_len - (iphdr->ihl * 4)); + inet_ntoa(*(struct in_addr *)&iphdr->daddr), + (size_t)buff_len - (iphdr->ihl * 4)); break; default: printf("%s: ICMP type %hhu, length %zu\n", - inet_ntoa(*(struct in_addr *)&iphdr->daddr), icmphdr->type, - (size_t)buff_len - (iphdr->ihl * 4)); + inet_ntoa(*(struct in_addr *)&iphdr->daddr), + icmphdr->type, + (size_t)buff_len - (iphdr->ihl * 4)); break; } break; case IPPROTO_TCP: - LEN_CHECK((size_t)buff_len - (iphdr->ihl * 4), sizeof(struct tcphdr), "TCP"); - - tcphdr = (struct tcphdr *)(packet_buff + (iphdr->ihl * 4)); - printf("IP %s.%i > ", inet_ntoa(*(struct in_addr *)&iphdr->saddr), ntohs(tcphdr->source)); - printf("%s.%i: TCP, flags [%c%c%c%c%c%c], length %zu\n", - inet_ntoa(*(struct in_addr *)&iphdr->daddr), ntohs(tcphdr->dest), - (tcphdr->fin ? 'F' : '.'), (tcphdr->syn ? 'S' : '.'), - (tcphdr->rst ? 'R' : '.'), (tcphdr->psh ? 'P' : '.'), - (tcphdr->ack ? 'A' : '.'), (tcphdr->urg ? 'U' : '.'), - (size_t)buff_len - (iphdr->ihl * 4) - sizeof(struct tcphdr)); + parse_tcp( + packet_buff, buff_len, iphdr->ihl * 4, + inet_ntoa(*(struct in_addr *)&iphdr->saddr), + inet_ntoa(*(struct in_addr *)&iphdr->daddr)); break; case IPPROTO_UDP: - LEN_CHECK((size_t)buff_len - (iphdr->ihl * 4), sizeof(struct udphdr), "UDP"); - - udphdr = (struct udphdr *)(packet_buff + (iphdr->ihl * 4)); - printf("IP %s.%i > ", inet_ntoa(*(struct in_addr *)&iphdr->saddr), ntohs(udphdr->source)); - - switch (ntohs(udphdr->dest)) { - case 67: - LEN_CHECK((size_t)buff_len - (iphdr->ihl * 4) - sizeof(struct udphdr), (size_t) 44, "DHCP"); - printf("%s.67: BOOTP/DHCP, Request from %s, length %zu\n", - inet_ntoa(*(struct in_addr *)&iphdr->daddr), - ether_ntoa_long((struct ether_addr *)(((char *)udphdr) + sizeof(struct udphdr) + 28)), - (size_t)buff_len - (iphdr->ihl * 4) - sizeof(struct udphdr)); - break; - case 68: - printf("%s.68: BOOTP/DHCP, Reply, length %zu\n", - inet_ntoa(*(struct in_addr *)&iphdr->daddr), - (size_t)buff_len - (iphdr->ihl * 4) - sizeof(struct udphdr)); - break; - default: - printf("%s.%i: UDP, length %zu\n", - inet_ntoa(*(struct in_addr *)&iphdr->daddr), ntohs(udphdr->dest), - (size_t)buff_len - (iphdr->ihl * 4) - sizeof(struct udphdr)); - break; - } - - break; - case IPPROTO_IPV6: - printf("IP6: not implemented yet\n"); + parse_udp( + packet_buff, buff_len, iphdr->ihl * 4, + inet_ntoa(*(struct in_addr *)&iphdr->saddr), + inet_ntoa(*(struct in_addr *)&iphdr->daddr)); break; default: printf("IP unknown protocol: %i\n", iphdr->protocol); @@ -497,6 +685,10 @@ static void parse_eth_hdr(unsigned char *packet_buff, ssize_t buff_len, int read if ((dump_level & DUMP_TYPE_NONBAT) || (time_printed)) dump_ip(packet_buff + ETH_HLEN, buff_len - ETH_HLEN, time_printed); break; + case ETH_P_IPV6: + if ((dump_level & DUMP_TYPE_NONBAT) || (time_printed)) + dump_ipv6(packet_buff + ETH_HLEN, buff_len - ETH_HLEN, time_printed); + break; case ETH_P_8021Q: if ((dump_level & DUMP_TYPE_NONBAT) || (time_printed)) dump_vlan(packet_buff, buff_len, read_opt, time_printed); -- 1.8.3.2

9 years, 8 months

[B.A.T.M.A.N.] [PATCH maint] batman-adv: set the TAG flag for the vid passed to BLA

by Antonio Quartulli

From: Antonio Quartulli <antonio(a)open-mesh.com> When receiving or sending a packet a packet on a VLAN, the vid has to be marked with the TAG flag in order to make any component in batman-adv understand that the packet is coming from a really tagged network. This fix the Bridge Loop Avoidance behaviour which was not able to send announces over VLAN interfaces. Introduced by 0b1da1765fdb00ca5d53bc95c9abc70dfc9aae5b ("batman-adv: change VID semantic in the BLA code") Signed-off-by: Antonio Quartulli <antonio(a)open-mesh.org> --- soft-interface.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/soft-interface.c b/soft-interface.c index 0f04e1c..33b6144 100644 --- a/soft-interface.c +++ b/soft-interface.c @@ -168,6 +168,7 @@ static int batadv_interface_tx(struct sk_buff *skb, case ETH_P_8021Q: vhdr = (struct vlan_ethhdr *)skb->data; vid = ntohs(vhdr->h_vlan_TCI) & VLAN_VID_MASK; + vid |= BATADV_VLAN_HAS_TAG; if (vhdr->h_vlan_encapsulated_proto != ethertype) break; @@ -329,6 +330,7 @@ void batadv_interface_rx(struct net_device *soft_iface, case ETH_P_8021Q: vhdr = (struct vlan_ethhdr *)skb->data; vid = ntohs(vhdr->h_vlan_TCI) & VLAN_VID_MASK; + vid |= BATADV_VLAN_HAS_TAG; if (vhdr->h_vlan_encapsulated_proto != ethertype) break; -- 1.8.1.5

9 years, 8 months

[B.A.T.M.A.N.] [RFCv2] batctl ping: add IPv6 to ethernet address resolution

by Marco Dalla Torre

Extends "batctl ping" command by allowing the user to specify a valid IPv6 address as target node. The corresponding ethernet link layer (MAC) address is then automatically resolved by the tool. This is possible by leveraging on a new set of library functions, added by this patch, when performing netlink queries towards the kernel network infrastructure. This new library can be found in "bat-mnl.c" and corresponding header "bat-mnl.h". The code has been taken from the libmnl project version 1.0.3 with minor modifications. The netlink query is needed to extract the ethernet address, corresponding to the target IPv6 address, from the local neighbor discovery table. If the target address is not initially found in the table, one or more datagrams are sent to initialize neighbor discovery exchange just like what already happens for ARP tables in the IPv4 case. The old IPv4 address resolution has also been updated to make use netlink queries (instead of looking into "/proc/net/arp") to allow for better code reuse and avoid depending on proc fs if not necessary. Signed-off-by: Marco Dalla Torre <marco.dallato(a)gmail.com> --- NOTABLE CHANGES FROM v1 - fixed accessing invalid memory - reuse code for IPv4 case Makefile | 2 +- bat-mnl.c | 560 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ bat-mnl.h | 92 ++++++++++ functions.c | 288 +++++++++++++++++++++---------- 4 files changed, 850 insertions(+), 92 deletions(-) create mode 100644 bat-mnl.c create mode 100644 bat-mnl.h diff --git a/Makefile b/Makefile index 1961298..c62b064 100755 --- a/Makefile +++ b/Makefile @@ -24,7 +24,7 @@ export CONFIG_BATCTL_BISECT=n # batctl build BINARY_NAME = batctl -OBJ = main.o bat-hosts.o functions.o sys.o debug.o ping.o traceroute.o tcpdump.o hash.o debugfs.o ioctl.o list-batman.o translate.o +OBJ = main.o bat-hosts.o functions.o sys.o debug.o ping.o traceroute.o tcpdump.o hash.o debugfs.o ioctl.o list-batman.o translate.o bat-mnl.o OBJ_BISECT = bisect_iv.o MANPAGE = man/batctl.8 diff --git a/bat-mnl.c b/bat-mnl.c new file mode 100644 index 0000000..66190ff --- /dev/null +++ b/bat-mnl.c @@ -0,0 +1,560 @@ +#include <stdlib.h> +#include <string.h> +#include <stdbool.h> +#include <sys/socket.h> +#include <errno.h> + +#include "bat-mnl.h" + +struct mnl_socket { + int fd; + struct sockaddr_nl addr; +}; + +/** + * mnl_nlmsg_get_payload - get a pointer to the payload of the netlink message + * @param nlh pointer to a netlink header + * + * This function returns a pointer to the payload of the netlink message. + */ +void *mnl_nlmsg_get_payload(const struct nlmsghdr *nlh) +{ + return (void *)nlh + MNL_NLMSG_HDRLEN; +} + +static int mnl_cb_noop(__attribute__((unused)) const struct nlmsghdr *nlh, + __attribute__((unused)) void *data) +{ + return MNL_CB_OK; +} + +/** + * mnl_nlmsg_size - calculate the size of Netlink message (without alignment) + * @param len length of the Netlink payload + * + * This function returns the size of a netlink message (header plus payload) + * without alignment. + */ +size_t mnl_nlmsg_size(size_t len) +{ + return len + MNL_NLMSG_HDRLEN; +} + +static int mnl_cb_error(const struct nlmsghdr *nlh, + __attribute__((unused))void *data) +{ + const struct nlmsgerr *err = mnl_nlmsg_get_payload(nlh); + + if (nlh->nlmsg_len < mnl_nlmsg_size(sizeof(struct nlmsgerr))) { + errno = EBADMSG; + return MNL_CB_ERROR; + } + /* Netlink subsystems returns the errno value with different signess */ + if (err->error < 0) + errno = -err->error; + else + errno = err->error; + + return err->error == 0 ? MNL_CB_STOP : MNL_CB_ERROR; +} + +static int mnl_cb_stop(__attribute__((unused)) const struct nlmsghdr *nlh, + __attribute__((unused))void *data) +{ + return MNL_CB_STOP; +} + +static const mnl_cb_t default_cb_array[NLMSG_MIN_TYPE] = { + [NLMSG_NOOP] = mnl_cb_noop, + [NLMSG_ERROR] = mnl_cb_error, + [NLMSG_DONE] = mnl_cb_stop, + [NLMSG_OVERRUN] = mnl_cb_noop, +}; + + +/* TLV iterators */ +/** + * mnl_attr_ok - check if there is room for an attribute in a buffer + * @param attr attribute that we want to check if there is room for + * @param len remaining bytes in a buffer that contains the attribute + * + * This function is used to check that a buffer, which is supposed to contain + * an attribute, has enough room for the attribute that it stores, i.e. this + * function can be used to verify that an attribute is neither malformed nor + * truncated. + * + * This function does not set errno in case of error since it is intended + * for iterations. Thus, it returns 1 on success and 0 on error. + * + * The len parameter may be negative in the case of malformed messages during + * attribute iteration, that is why we use a signed integer. + */ +bool mnl_attr_ok(const struct nlattr *attr, int len) +{ + return len >= (int)sizeof(struct nlattr) && + attr->nla_len >= sizeof(struct nlattr) && + (int)attr->nla_len <= len; +} + +/** + * mnl_attr_next - get the next attribute in the payload of a netlink message + * @param attr pointer to the current attribute + * @param len length of the remaining bytes in the buffer (passed by reference). + * + * This function returns a pointer to the next attribute after the one passed + * as parameter. You have to use mnl_attr_ok() to ensure that the next + * attribute is valid. + */ +struct nlattr *mnl_attr_next(const struct nlattr *attr) +{ + return (struct nlattr *)((void *)attr + MNL_ALIGN(attr->nla_len)); +} + +/** + * mnl_nlmsg_get_payload_tail - get the ending of the netlink message + * @param nlh pointer to netlink message + * + * This function returns a pointer to the netlink message tail. This is useful + * to build a message since we continue adding attributes at the end of the + * message. + */ +void *mnl_nlmsg_get_payload_tail(const struct nlmsghdr *nlh) +{ + return (void *)nlh + MNL_ALIGN(nlh->nlmsg_len); +} + +/** + * mnl_nlmsg_get_payload_offset - get a pointer to the payload of the message + * @param nlh pointer to a netlink header + * @param offset offset to the payload of the attributes TLV set + * + * This function returns a pointer to the payload of the netlink message plus + * a given offset. + */ +void *mnl_nlmsg_get_payload_offset(const struct nlmsghdr *nlh, size_t offset) +{ + return (void *)nlh + MNL_NLMSG_HDRLEN + MNL_ALIGN(offset); +} + + +/** + * mnl_attr_get_type - get type of netlink attribute + * @param attr pointer to netlink attribute + * + * This function returns the attribute type. + */ +uint16_t mnl_attr_get_type(const struct nlattr *attr) +{ + return attr->nla_type & NLA_TYPE_MASK; +} + +/** + * mnl_attr_type_valid - check if the attribute type is valid + * @param attr pointer to attribute to be checked + * @param max maximum attribute type + * + * This function allows to check if the attribute type is higher than the + * maximum supported type. If the attribute type is invalid, this function + * returns -1 and errno is explicitly set. On success, this function returns 1. + * + * Strict attribute checking in user-space is not a good idea since you may + * run an old application with a newer kernel that supports new attributes. + * This leads to backward compatibility breakages in user-space. Better check + * if you support an attribute, if not, skip it. + */ +int mnl_attr_type_valid(const struct nlattr *attr, uint16_t max) +{ + if (mnl_attr_get_type(attr) > max) { + errno = EOPNOTSUPP; + return -1; + } + return 1; +} + +/** + * mnl_attr_parse - parse attributes + * @param nlh pointer to netlink message + * @param offset offset to start parsing from (if payload is after any header) + * @param cb callback function that is called for each attribute + * @param data pointer to data that is passed to the callback function + * + * This function allows to iterate over the sequence of attributes that compose + * the Netlink message. You can then put the attribute in an array as it + * usually happens at this stage or you can use any other data structure (such + * as lists or trees). + * + * This function propagates the return value of the callback, which can be + * MNL_CB_ERROR, MNL_CB_OK or MNL_CB_STOP. + */ +int +mnl_attr_parse(const struct nlmsghdr *nlh, unsigned int offset, + mnl_attr_cb_t cb, void *data) +{ + int ret = MNL_CB_OK; + const struct nlattr *attr; + + mnl_attr_for_each(attr, nlh, offset) { + ret = cb(attr, data); + if (ret <= MNL_CB_STOP) + return ret; + } + return ret; +} + +/** + * mnl_nlmsg_put_extra_header - reserve and prepare room for an extra header + * @param nlh pointer to Netlink header + * @param size size of the extra header that we want to put + * + * This function sets to zero the room that is required to put the extra + * header after the initial Netlink header. This function also increases + * the nlmsg_len field. You have to invoke mnl_nlmsg_put_header() before + * you call this function. This function returns a pointer to the extra + * header. + */ +void * +mnl_nlmsg_put_extra_header(struct nlmsghdr *nlh, size_t size) +{ + char *ptr = (char *)nlh + nlh->nlmsg_len; + size_t len = MNL_ALIGN(size); + nlh->nlmsg_len += len; + memset(ptr, 0, len); + return ptr; +} + +/** + * mnl_nlmsg_put_header - reserve and prepare room for Netlink header + * @param buf memory already allocated to store the Netlink header + * + * This function sets to zero the room that is required to put the Netlink + * header in the memory buffer passed as parameter. This function also + * initializes the nlmsg_len field to the size of the Netlink header. This + * function returns a pointer to the Netlink header structure. + */ +struct nlmsghdr *mnl_nlmsg_put_header(void *buf) +{ + int len = MNL_ALIGN(sizeof(struct nlmsghdr)); + struct nlmsghdr *nlh = buf; + + memset(buf, 0, len); + nlh->nlmsg_len = len; + return nlh; +} + +/** + * mnl_socket_open - open a netlink socket + * @param bus the netlink socket bus ID (see NETLINK_* constants) + * + * On error, it returns -1 and errno is appropriately set. Otherwise, it + * returns a valid pointer to the mnl_socket structure. + */ +struct mnl_socket *mnl_socket_open(int bus) +{ + struct mnl_socket *nl; + + nl = calloc(sizeof(struct mnl_socket), 1); + if (nl == NULL) + return NULL; + + nl->fd = socket(AF_NETLINK, SOCK_RAW, bus); + if (nl->fd == -1) { + free(nl); + return NULL; + } + + return nl; +} + +/** + * mnl_socket_bind - bind netlink socket + * @param nl netlink socket obtained via mnl_socket_open() + * @param groups the group of message you're interested in + * @param pid the port ID you want to use (use zero for automatic selection) + * + * On error, this function returns -1 and errno is appropriately set. On + * success, 0 is returned. You can use MNL_SOCKET_AUTOPID which is 0 for + * automatic port ID selection. + */ +int mnl_socket_bind(struct mnl_socket *nl, unsigned int groups, pid_t pid) +{ + int ret; + socklen_t addr_len; + + nl->addr.nl_family = AF_NETLINK; + nl->addr.nl_groups = groups; + nl->addr.nl_pid = pid; + + ret = bind(nl->fd, (struct sockaddr *) &nl->addr, sizeof(nl->addr)); + if (ret < 0) + return ret; + + addr_len = sizeof(nl->addr); + ret = getsockname(nl->fd, (struct sockaddr *) &nl->addr, &addr_len); + if (ret < 0) + return ret; + + if (addr_len != sizeof(nl->addr)) { + errno = EINVAL; + return -1; + } + if (nl->addr.nl_family != AF_NETLINK) { + errno = EINVAL; + return -1; + } + return 0; +} + +/** + * mnl_socket_get_portid - obtain Netlink PortID from netlink socket + * @param nl netlink socket obtained via mnl_socket_open() + * + * This function returns the Netlink PortID of a given netlink socket. + * It's a common mistake to assume that this PortID equals the process ID + * which is not always true. This is the case if you open more than one + * socket that is binded to the same Netlink subsystem from the same process. + */ +unsigned int mnl_socket_get_portid(const struct mnl_socket *nl) +{ + return nl->addr.nl_pid; +} + +/** + * mnl_socket_sendto - send a netlink message of a certain size + * @param nl netlink socket obtained via mnl_socket_open() + * @param buf buffer containing the netlink message to be sent + * @param len number of bytes in the buffer that you want to send + * + * On error, it returns -1 and errno is appropriately set. Otherwise, it + * returns the number of bytes sent. + */ +ssize_t +mnl_socket_sendto(const struct mnl_socket *nl, const void *buf, size_t len) +{ + static const struct sockaddr_nl snl = { + .nl_family = AF_NETLINK + }; + return sendto(nl->fd, buf, len, 0, + (struct sockaddr *) &snl, sizeof(snl)); +} + +/** + * mnl_socket_recvfrom - receive a netlink message + * @param nl netlink socket obtained via mnl_socket_open() + * @param buf buffer that you want to use to store the netlink message + * @param bufsiz size of the buffer passed to store the netlink message + * + * On error, it returns -1 and errno is appropriately set. If errno is set + * to ENOSPC, it means that the buffer that you have passed to store the + * netlink message is too small, so you have received a truncated message. + * To avoid this, you have to allocate a buffer of MNL_SOCKET_BUFFER_SIZE + * (which is 8KB, see linux/netlink.h for more information). Using this + * buffer size ensures that your buffer is big enough to store the netlink + * message without truncating it. + */ +ssize_t +mnl_socket_recvfrom(const struct mnl_socket *nl, void *buf, size_t bufsiz) +{ + ssize_t ret; + struct sockaddr_nl addr; + struct iovec iov = { + .iov_base = buf, + .iov_len = bufsiz, + }; + struct msghdr msg = { + .msg_name = &addr, + .msg_namelen = sizeof(struct sockaddr_nl), + .msg_iov = &iov, + .msg_iovlen = 1, + .msg_control = NULL, + .msg_controllen = 0, + .msg_flags = 0, + }; + ret = recvmsg(nl->fd, &msg, 0); + if (ret == -1) + return ret; + + if (msg.msg_flags & MSG_TRUNC) { + errno = ENOSPC; + return -1; + } + if (msg.msg_namelen != sizeof(struct sockaddr_nl)) { + errno = EINVAL; + return -1; + } + return ret; +} + +/** + * mnl_nlmsg_portid_ok - perform portID origin check + * @param nlh current netlink message that we are handling + * @param portid netlink portid that we want to check + * + * This functions returns true if the origin is fulfilled, otherwise + * false is returned. We skip the tracking for netlink message whose portID + * is zero since it is reserved for event-based kernel notifications. On the + * other hand, if portid is set but the message PortID is not (i.e. this + * is an event message coming from kernel-space), then we also skip the + * tracking. This approach is good if we use the same socket to send commands + * to kernel-space (that we want to track) and to listen to events (that we + * do not track). + */ +bool +mnl_nlmsg_portid_ok(const struct nlmsghdr *nlh, unsigned int portid) +{ + return nlh->nlmsg_pid && portid ? nlh->nlmsg_pid == portid : true; +} + +/** + * mnl_nlmsg_ok - check a there is room for netlink message + * @param nlh netlink message that we want to check + * @param len remaining bytes in a buffer that contains the netlink message + * + * This function is used to check that a buffer that contains a netlink + * message has enough room for the netlink message that it stores, ie. this + * function can be used to verify that a netlink message is not malformed nor + * truncated. + * + * This function does not set errno in case of error since it is intended + * for iterations. Thus, it returns 1 on success and 0 on error. + * + * The len parameter may become negative in malformed messages during message + * iteration, that is why we use a signed integer. + */ +bool mnl_nlmsg_ok(const struct nlmsghdr *nlh, int len) +{ + return len >= (int)sizeof(struct nlmsghdr) && + nlh->nlmsg_len >= sizeof(struct nlmsghdr) && + (int)nlh->nlmsg_len <= len; +} + +/** + * mnl_nlmsg_next - get the next netlink message in a multipart message + * @param nlh current netlink message that we are handling + * @param len length of the remaining bytes in the buffer (passed by reference). + * + * This function returns a pointer to the next netlink message that is part + * of a multi-part netlink message. Netlink can batch several messages into + * one buffer so that the receiver has to iterate over the whole set of + * Netlink messages. + * + * You have to use mnl_nlmsg_ok() to check if the next Netlink message is + * valid. + */ +struct nlmsghdr * +mnl_nlmsg_next(const struct nlmsghdr *nlh, int *len) +{ + *len -= MNL_ALIGN(nlh->nlmsg_len); + return (struct nlmsghdr *)((void *)nlh + MNL_ALIGN(nlh->nlmsg_len)); +} + +/** + * mnl_nlmsg_seq_ok - perform sequence tracking + * @param nlh current netlink message that we are handling + * @param seq last sequence number used to send a message + * + * This functions returns true if the sequence tracking is fulfilled, otherwise + * false is returned. We skip the tracking for netlink messages whose sequence + * number is zero since it is usually reserved for event-based kernel + * notifications. On the other hand, if seq is set but the message sequence + * number is not set (i.e. this is an event message coming from kernel-space), + * then we also skip the tracking. This approach is good if we use the same + * socket to send commands to kernel-space (that we want to track) and to + * listen to events (that we do not track). + */ +bool +mnl_nlmsg_seq_ok(const struct nlmsghdr *nlh, unsigned int seq) +{ + return nlh->nlmsg_seq && seq ? nlh->nlmsg_seq == seq : true; +} + +static inline int +__mnl_cb_run(const void *buf, size_t numbytes, unsigned int seq, + unsigned int portid, mnl_cb_t cb_data, void *data, + mnl_cb_t *cb_ctl_array, unsigned int cb_ctl_array_len) +{ + int ret = MNL_CB_OK, len = numbytes; + const struct nlmsghdr *nlh = buf; + + while (mnl_nlmsg_ok(nlh, len)) { + /* check message source */ + if (!mnl_nlmsg_portid_ok(nlh, portid)) { + errno = ESRCH; + return -1; + } + /* perform sequence tracking */ + if (!mnl_nlmsg_seq_ok(nlh, seq)) { + errno = EPROTO; + return -1; + } + + /* dump was interrupted */ + if (nlh->nlmsg_flags & NLM_F_DUMP_INTR) { + errno = EINTR; + return -1; + } + + /* netlink data message handling */ + if (nlh->nlmsg_type >= NLMSG_MIN_TYPE) { + if (cb_data) { + ret = cb_data(nlh, data); + if (ret <= MNL_CB_STOP) + goto out; + } + } else if (nlh->nlmsg_type < cb_ctl_array_len) { + if (cb_ctl_array && cb_ctl_array[nlh->nlmsg_type]) { + ret = cb_ctl_array[nlh->nlmsg_type](nlh, data); + if (ret <= MNL_CB_STOP) + goto out; + } + } else if (default_cb_array[nlh->nlmsg_type]) { + ret = default_cb_array[nlh->nlmsg_type](nlh, data); + if (ret <= MNL_CB_STOP) + goto out; + } + nlh = mnl_nlmsg_next(nlh, &len); + } +out: + return ret; +} + +/** + * mnl_cb_run - callback runqueue for netlink messages (simplified version) + * @param buf buffer that contains the netlink messages + * @param numbytes number of bytes stored in the buffer + * @param seq sequence number that we expect to receive + * @param portid Netlink PortID that we expect to receive + * @param cb_data callback handler for data messages + * @param data pointer to data that will be passed to the data callback handler + * + * This function is like mnl_cb_run2() but it does not allow you to set + * the control callback handlers. + * + * Your callback may return three possible values: + * - MNL_CB_ERROR (<=-1): an error has occurred. Stop callback runqueue. + * - MNL_CB_STOP (=0): stop callback runqueue. + * - MNL_CB_OK (>=1): no problems has occurred. + * + * This function propagates the callback return value. + */ +int +mnl_cb_run(const void *buf, size_t numbytes, unsigned int seq, + unsigned int portid, mnl_cb_t cb_data, void *data) +{ + return __mnl_cb_run(buf, numbytes, seq, portid, cb_data, data, NULL, 0); +} + + +/** + * mnl_socket_close - close a given netlink socket + * @param nl netlink socket obtained via mnl_socket_open() + * + * On error, this function returns -1 and errno is appropriately set. + * On success, it returns 0. + */ +int mnl_socket_close(struct mnl_socket *nl) +{ + int ret = close(nl->fd); + free(nl); + return ret; +} + diff --git a/bat-mnl.h b/bat-mnl.h new file mode 100644 index 0000000..255b568 --- /dev/null +++ b/bat-mnl.h @@ -0,0 +1,92 @@ +#ifndef _BATMNL_H_ +#define _BATMNL_H_ + +#include <unistd.h> +#include <stdint.h> +#include <linux/netlink.h> +#include <linux/rtnetlink.h> + +/* + * Netlink socket API + */ +#define MNL_SOCKET_AUTOPID 0 +#define MNL_SOCKET_BUFFER_SIZE (getpagesize() < 8192L ? getpagesize() : 8192L) + +/* + * nla_type (16 bits) + * +---+---+-------------------------------+ + * | N | O | Attribute Type | + * +---+---+-------------------------------+ + * N := Carries nested attributes + * O := Payload stored in network byte order + * + * Note: The N and O flag are mutually exclusive. + */ +#define NLA_F_NESTED (1 << 15) +#define NLA_F_NET_BYTEORDER (1 << 14) +#define NLA_TYPE_MASK ~(NLA_F_NESTED | NLA_F_NET_BYTEORDER) + +struct mnl_socket; + +extern struct mnl_socket *mnl_socket_open(int type); +extern int mnl_socket_bind(struct mnl_socket *nl, + unsigned int groups, pid_t pid); +extern int mnl_socket_close(struct mnl_socket *nl); +extern unsigned int mnl_socket_get_portid(const struct mnl_socket *nl); +extern ssize_t mnl_socket_sendto(const struct mnl_socket *nl, + const void *req, size_t siz); +extern ssize_t mnl_socket_recvfrom(const struct mnl_socket *nl, void *buf, + size_t siz); + +/* + * Netlink message API + */ +#define MNL_ALIGNTO 4 +#define MNL_ALIGN(len) (((len)+MNL_ALIGNTO-1) & ~(MNL_ALIGNTO-1)) +#define MNL_NLMSG_HDRLEN MNL_ALIGN(sizeof(struct nlmsghdr)) + + +/* + * callback API + */ + +#define MNL_CB_ERROR -1 +#define MNL_CB_STOP 0 +#define MNL_CB_OK 1 + +typedef int (*mnl_cb_t)(const struct nlmsghdr *nlh, void *data); + +extern int mnl_cb_run(const void *buf, size_t numbytes, unsigned int seq, + unsigned int portid, mnl_cb_t cb_data, void *data); + +/* TLV callback-based attribute parsers */ +typedef int (*mnl_attr_cb_t)(const struct nlattr *attr, void *data); + +extern int mnl_attr_parse(const struct nlmsghdr *nlh, unsigned int offset, + mnl_attr_cb_t cb, void *data); + + +#define mnl_attr_for_each(attr, nlh, offset) \ + for ((attr) = mnl_nlmsg_get_payload_offset((nlh), (offset)); \ + mnl_attr_ok((attr), (char *)mnl_nlmsg_get_payload_tail( \ + nlh) - (char *)(attr)); \ + (attr) = mnl_attr_next(attr)) + + +/* Netlink message getters */ +extern void *mnl_nlmsg_get_payload(const struct nlmsghdr *nlh); +extern void *mnl_nlmsg_get_payload_offset(const struct nlmsghdr *nlh, + size_t offset); +extern void *mnl_nlmsg_get_payload_tail(const struct nlmsghdr *nlh); + +/* TLV attribute getters */ +extern uint16_t mnl_attr_get_type(const struct nlattr *attr); + +/* TLV validation */ +extern int mnl_attr_type_valid(const struct nlattr *attr, uint16_t maxtype); + +/* Netlink message header builder */ +extern struct nlmsghdr *mnl_nlmsg_put_header(void *buf); +extern void *mnl_nlmsg_put_extra_header(struct nlmsghdr *nlh, size_t size); + +#endif diff --git a/functions.c b/functions.c index cc05a48..159b3ea 100644 --- a/functions.c +++ b/functions.c @@ -34,14 +34,20 @@ #include <errno.h> #include <fcntl.h> #include <sys/time.h> +#include <time.h> +#include <netinet/in.h> #include "main.h" #include "functions.h" +#include "bat-mnl.h" #include "bat-hosts.h" #include "sys.h" #include "debug.h" #include "debugfs.h" + +#define CB_FINISH -2 + static struct timeval start_time; static char *host_name; char *line_ptr = NULL; @@ -413,134 +419,233 @@ out: return mac_result; } -static uint32_t resolve_ipv4(const char *asc) +static void *resolve_ip(const int address_family, const char *asc) { int ret; struct addrinfo hints; struct addrinfo *res; - struct sockaddr_in *inet4; - uint32_t addr = 0; + void *retval; memset(&hints, 0, sizeof(hints)); - hints.ai_family = AF_INET; + hints.ai_family = address_family; ret = getaddrinfo(asc, NULL, &hints, &res); + if (ret) - return 0; + return NULL; if (res) { - inet4 = (struct sockaddr_in *)res->ai_addr; - addr = inet4->sin_addr.s_addr; + if (address_family == AF_INET) { + struct sockaddr_in *inet = + (struct sockaddr_in *)res->ai_addr; + struct in_addr *naddr = &(inet->sin_addr); + + retval = malloc(sizeof(struct in_addr)); + memcpy(retval, naddr, sizeof(struct in_addr)); + } else if (address_family == AF_INET6) { + struct sockaddr_in6 *inet = + (struct sockaddr_in6 *)res->ai_addr; + struct in6_addr *naddr = &(inet->sin6_addr); + + retval = malloc(sizeof(struct in6_addr)); + memcpy(retval, naddr, sizeof(struct in6_addr)); + } } - freeaddrinfo(res); - return addr; + return retval; } -static void request_arp(uint32_t ipv4_addr) + +static void request_arp_nd(const int address_family, const void *addr) { - struct sockaddr_in inet4; int sock; char t = 0; + ssize_t length; + sock = socket(address_family, SOCK_DGRAM, IPPROTO_UDP); - memset(&inet4, 0, sizeof(inet4)); - sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP); if (sock < 0) return; - inet4.sin_family = AF_INET; - inet4.sin_port = htons(9); - inet4.sin_addr.s_addr = ipv4_addr; - sendto(sock, &t, sizeof(t), 0, (const struct sockaddr *)&inet4, - sizeof(inet4)); + const struct sockaddr *saddr; + if (address_family == AF_INET) { + struct sockaddr_in inet4; + memset(&inet4, 0, sizeof(struct sockaddr_in)); + inet4.sin_family = AF_INET; + inet4.sin_port = htons(9); + memcpy(&(inet4.sin_addr), addr, sizeof(struct in_addr)); + saddr = (const struct sockaddr *)&inet4; + length = sizeof(inet4); + } else if (address_family == AF_INET6) { + struct sockaddr_in6 inet; + memset(&inet, 0, sizeof(struct sockaddr_in6)); + inet.sin6_family = AF_INET6; + inet.sin6_port = htons(9); + memcpy(&(inet.sin6_addr), addr, sizeof(struct in6_addr)); + saddr = (const struct sockaddr *)&inet; + length = sizeof(inet); + } + + sendto(sock, &t, sizeof(t), 0, saddr, length); close(sock); } -static struct ether_addr *resolve_mac_from_arp(uint32_t ipv4_addr) +/* + * Data structure used to hold input and output data for/from netlink + * neighbor discovery query callback function + */ +struct ip_lladdr { + int address_family; + const void *addr; + struct ether_addr *ll_addr; +}; + +/* + * Callback function called during netlink message parsing. Popolates the array + * obtained in input with parsed elements from each netlink attribute found in + * the payload message. + * @attr: message current attribute + * @data: array to populate + * + * @return outcome of attribute parsing + */ +static int data_attr_cb(const struct nlattr *attr, void *data) { - struct ether_addr mac_empty; - struct ether_addr *mac_result = NULL, *mac_tmp = NULL; - struct sockaddr_in inet4; + const struct nlattr **tb = data; + int type = mnl_attr_get_type(attr); + + /* skip unsupported attribute in user-space */ + if (mnl_attr_type_valid(attr, NDA_MAX) < 0) + return MNL_CB_OK; + tb[type] = attr; + return MNL_CB_OK; +} + +/* + * Callback function, called on every netlink packet received in response + * of the query. + */ +static int data_cb_neigh(const struct nlmsghdr *nlh, void *data) +{ + struct rtattr *tb[NDA_MAX+1] = {}; + struct ndmsg *ndm = mnl_nlmsg_get_payload(nlh); + struct ip_lladdr *inout = data; + size_t expected_size; + int expected_family = inout->address_family; + + if (inout->address_family == AF_INET) + expected_size = sizeof(struct in_addr); + else if (inout->address_family == AF_INET6) + expected_size = sizeof(struct in6_addr); + else + return MNL_CB_ERROR; /* address type invalid */ + + if (ndm->ndm_family != expected_family && + (ndm->ndm_state != NUD_REACHABLE + || ndm->ndm_state != NUD_STALE)) { + return MNL_CB_OK; + } + + mnl_attr_parse(nlh, sizeof(*ndm), data_attr_cb, tb); + + if (!tb[NDA_LLADDR] || !tb[NDA_DST]) + return MNL_CB_OK; + + if (RTA_PAYLOAD(tb[NDA_DST]) != expected_size) + return MNL_CB_OK; + + if (memcmp(inout->addr, RTA_DATA(tb[NDA_DST]), expected_size) == 0) { + inout->ll_addr = malloc(sizeof(struct ether_addr)); + memcpy(inout->ll_addr, + RTA_DATA(tb[NDA_LLADDR]), RTA_PAYLOAD(tb[NDA_LLADDR])); + return CB_FINISH; + } + return MNL_CB_OK; +} + +/* + * Queries the kernel for the link layer (ethernet) address corresponding to + * the given IPv6 address. + * @in6_addr: address that needs to be resolved + * + * Returns the ethernet address if found, NULL otherwise + */ +static struct ether_addr *resolve_mac_from_nl(const int address_family, + const void *addr) +{ + struct mnl_socket *nl; + char buf[MNL_SOCKET_BUFFER_SIZE]; + struct nlmsghdr *nlh; + struct ndmsg *ndm; int ret; - FILE *f; - size_t len = 0; - char *line = NULL; - int skip_line = 1; - size_t column; - char *token, *input, *saveptr; - int line_invalid; - - memset(&mac_empty, 0, sizeof(mac_empty)); - - f = fopen("/proc/net/arp", "r"); - if (!f) - return NULL; - - while (getline(&line, &len, f) != -1) { - if (skip_line) { - skip_line = 0; - continue; - } - - line_invalid = 0; - column = 0; - input = line; - while ((token = strtok_r(input, " \t", &saveptr))) { - input = NULL; - - if (column == 0) { - ret = inet_pton(AF_INET, token, &inet4.sin_addr); - if (ret != 1) { - line_invalid = 1; - break; - } - } - - if (column == 3) { - mac_tmp = ether_aton(token); - if (!mac_tmp || memcmp(mac_tmp, &mac_empty, - sizeof(mac_empty)) == 0) { - line_invalid = 1; - break; - } - } - - column++; - } - - if (column < 4) - line_invalid = 1; - - if (line_invalid) - continue; - - if (ipv4_addr == inet4.sin_addr.s_addr) { - mac_result = mac_tmp; + unsigned int seq, portid; + + struct ip_lladdr inout = { + .address_family = address_family, + .addr = addr, + .ll_addr = NULL + }; + + nlh = mnl_nlmsg_put_header(buf); + nlh->nlmsg_type = RTM_GETNEIGH; /*RTM_GETNEIGHTBL RTM_GETNEIGH*/ + nlh->nlmsg_flags = NLM_F_REQUEST | NLM_F_DUMP; + nlh->nlmsg_seq = seq = time(NULL); + ndm = mnl_nlmsg_put_extra_header(nlh, sizeof(*ndm)); + ndm->ndm_family = address_family; + + nl = mnl_socket_open(NETLINK_ROUTE); + if (nl == NULL) { + perror("mnl_socket_open"); + exit(EXIT_FAILURE); + } + if (mnl_socket_bind(nl, 0, MNL_SOCKET_AUTOPID) < 0) { + perror("mnl_socket_bind"); + exit(EXIT_FAILURE); + } + portid = mnl_socket_get_portid(nl); + + if (mnl_socket_sendto(nl, nlh, nlh->nlmsg_len) < 0) { + perror("mnl_socket_send"); + exit(EXIT_FAILURE); + } + ret = mnl_socket_recvfrom(nl, buf, sizeof(buf)); + + while (ret > 0) { + ret = mnl_cb_run(buf, ret, seq, portid, data_cb_neigh, &inout); + if (ret <= MNL_CB_STOP) break; - } + ret = mnl_socket_recvfrom(nl, buf, sizeof(buf)); } + if (ret == MNL_CB_ERROR) { + perror("error"); + exit(EXIT_FAILURE); + } + mnl_socket_close(nl); - free(line); - fclose(f); - return mac_result; + return inout.ll_addr; } -static struct ether_addr *resolve_mac_from_ipv4(const char *asc) +static struct ether_addr *resolve_mac_from_af(const int address_family, + const char *asc) { - uint32_t ipv4_addr; + void *ip_addr; + + if (address_family == AF_INET) + ip_addr = resolve_ip(address_family, asc); + else if (address_family == AF_INET6) { + ip_addr = resolve_ip(address_family, asc); + + if (!ip_addr) + return NULL; + int retries = 5; struct ether_addr *mac_result = NULL; - - ipv4_addr = resolve_ipv4(asc); - if (!ipv4_addr) - return NULL; - while (retries-- && !mac_result) { - mac_result = resolve_mac_from_arp(ipv4_addr); + mac_result = resolve_mac_from_nl(address_family, ip_addr); if (!mac_result) { - request_arp(ipv4_addr); + request_arp_nd(address_family, ip_addr); usleep(200000); } } + free(ip_addr); return mac_result; } @@ -553,8 +658,9 @@ struct ether_addr *resolve_mac(const char *asc) if (mac_result) goto out; - mac_result = resolve_mac_from_ipv4(asc); - + mac_result = resolve_mac_from_af(AF_INET, asc); + if (!mac_result) + mac_result = resolve_mac_from_af(AF_INET6, asc); out: return mac_result; } -- 1.8.3.2

9 years, 8 months

[B.A.T.M.A.N.] Network Coding testing.

by ajeet singh

Hello All, I am trying to test network coding functionality of batman-adv. I am facing some problems. Please find my topology information, I created network with three nodes ( ad-hoc), Node A --- Node B --- Node C I did following settings, --- Complied latest batman-adv. with NC enabled. --- I did all setting form http://www.open-mesh.org/projects/batman-adv/wiki/NetworkCoding --- Kept all nodes in promiscuous mode. (Nodes are working properly in this mode). When I started iperf (TCP) from node A to node C, Node B stopped responding after few seconds. B is not sending OGM to A and C. When I tested without NC everything work fine. Is there any additional settings required for NC test? Please let me know if anyone faced similar issues. Thanks Ajeet On Thu, Sep 12, 2013 at 3:30 PM, <b.a.t.m.a.n-request(a)lists.open-mesh.org> wrote: > Send B.A.T.M.A.N mailing list submissions to > b.a.t.m.a.n(a)lists.open-mesh.org > > To subscribe or unsubscribe via the World Wide Web, visit > https://lists.open-mesh.org/mm/listinfo/b.a.t.m.a.n > or, via email, send a message with subject or body 'help' to > b.a.t.m.a.n-request(a)lists.open-mesh.org > > You can reach the person managing the list at > b.a.t.m.a.n-owner(a)lists.open-mesh.org > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of B.A.T.M.A.N digest..." > > > Today's Topics: > > 1. Fwd: Re: Hamburg freifunk geekend02 (Nicol?s Ech?niz) > 2. fool batman by simulating a layer3 mesh (Bastian Bittorf) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Wed, 11 Sep 2013 20:47:54 -0300 > From: Nicol?s Ech?niz <nicoechaniz(a)altermundi.net> > To: The list for a Better Approach To Mobile Ad-hoc Networking > <b.a.t.m.a.n(a)lists.open-mesh.org> > Subject: [B.A.T.M.A.N.] Fwd: Re: Hamburg freifunk geekend02 > Message-ID: <5231012A.60709(a)altermundi.net> > Content-Type: text/plain; charset=UTF-8 > > I'm forwarding this e-mail to the list per request of Andre. > > > -------- Mensaje original -------- > Asunto: Re: [B.A.T.M.A.N.] Hamburg freifunk geekend02 > Fecha: Wed, 11 Sep 2013 10:18:09 +0200 > De: Andre Schmidt <m.andre.schmidt(a)me.com> > A: nicoechaniz(a)altermundi.net <nicoechaniz(a)altermundi.net> > > > > A filter on the list rejects my answer, so I can only answer to you. > Maybe you can forward it to the list, in case others care as well. thanks > > > Hi Nico, > > By physically connected you mean wireless mesh and by VPN you mean > cable-based VPN over the internet? > Mostly the latter, but it is mixed. You can check out our node graph [0] > to get an impression of the topology. > > See you in Berlin, > andre > > [0] http://knotengraph.de <http://knotengraph.de> > > > Am 11.09.2013 um 10:00 schrieb Nicol?s Ech?niz > <nicoechaniz(a)altermundi.net <mailto:nicoechaniz@altermundi.net>>: > >> El 07/09/13 06:38, Andre Schmidt escribi?: >>> Hi there, >>> >>> Sep. 27.-29., 2013, we'll meet up for geekend02 [0] at B?rgerhaus >>> Hamburg-Eidelstedt, Germany. This is going to be a great opportunity >>> to meet AFK. Naturally, you can bring your own keyboard, so it's all >>> good, don't worry. >>> >>> Since Hamburg is probably one of the larger B.A.T.M.A.N. networks on >>> this planet w/ 300+ routers constantly online and still growing >>> rapidly, we do fear that we'll run into scaling problems sooner or >>> later. Therefore, your expertise on how to counteract is very >>> welcome. >> >> sounds very interesting, please document :) >> >> are this 300+ routers physically connected or is it mostly VPN? >> >> hope to meet some of you during the summit in Berlin and to hear more >> about your conclusions regarding scalability. >> >> >> cheers, >> Nico >> > > > > > ------------------------------ > > Message: 2 > Date: Thu, 12 Sep 2013 11:36:41 +0200 > From: Bastian Bittorf <bittorf(a)bluebottle.com> > To: b.a.t.m.a.n(a)lists.open-mesh.org > Subject: [B.A.T.M.A.N.] fool batman by simulating a layer3 mesh > Message-ID: <20130912093641.GX1558(a)medion.lan> > Content-Type: text/plain; charset=us-ascii > > discussed in IRC, i'am searched for a better way to > load-balance a batman network. not the whole shaping/splashing > should run on one (central) node, so we needed something to stick it > to the node/AP which the user is connected to. than we have also > the ability to show a good page when the network is b0rken. > > short overview: > > NODE-1 (master/gateway) > ipv4: 192.168.1.1/16 > dhcp: 192.168.1.x / gateway: 192.168.0.1 > gateway: e.g. pppoe > > NODE-2 > ipv4: 192.168.2.1/16 > dhcp: 192.168.2.x / gateway: 192.168.0.1 > gateway: 192.168.1.1 > > NODE-3 > ipv4: 192.168.3.1/16 > dhcp: 192.168.3.x / gateway: 192.168.0.1 > gateway: 192.168.1.1 > > the trick is, that every node offers DHCP which > does not interfere with other nodes AND offers a > gateway which is always the same: 192.168.0.1 > > if a user roams he simply moves on layer 1/2 and > its further working ok. important: the MAC of the > gateway should not change otherwise it's not working > for some seconds till the ARP times out. this can > be circumvented via kmod-macvlan: > > ip link add link br-mybridge gateway0 address '02:00:c0:ca:c0:1a' type macvlan > ip address add 192.168.0.1/16 dev gateway0 > ip link set dev gateway0 up > > then the IP 192.168.0.1 is always reachable with the same MAC. > thats it. we can use the "normal" iptables/tc stuff like in > olsrd-networks... > > giving out such dhcp-leases needs a fix to /etc/init.d/dhcp > which is available soon on OpenWrt mailinglist. > > bye, bastian > > PS: > thanks for the discussion and help, escpecially to T_X, ordex and marec > > > ------------------------------ > > Subject: Digest Footer > > _______________________________________________ > B.A.T.M.A.N mailing list > B.A.T.M.A.N(a)lists.open-mesh.org > https://lists.open-mesh.org/mm/listinfo/b.a.t.m.a.n > > > ------------------------------ > > End of B.A.T.M.A.N Digest, Vol 81, Issue 25 > ******************************************* -- Thanks Ajeet

9 years, 8 months

[B.A.T.M.A.N.] batmand: Debian patches for 0.3.2+51+g1e275d9-1

by Sven Eckelmann

Hi, different patches [1] were aggregated in the Debian package of batmand 0.3.2+51+g1e275d9-1. Kind regards, Sven [1] http://anonscm.debian.org/gitweb/?p=collab-maint/batmand.git;a=tree;f=debia…

9 years, 8 months

[B.A.T.M.A.N.] [PATCHv8] batctl: add sys framework for VLAN support

by Marco Dalla Torre

Allow the batctl tool to take advantage of changes from commit e4ff5c153dab054a6cd1c4132f87bc5e77127456 "add sys framework for VLAN" recently added to batman-adv, so that users can execute commands in a per VLAN fashion. If no directory entry corresponding to the user-selected device is found at the standard location for non VLAN interfaces (/sys/class/net/${device}/mesh/), 'batctl' now looks into directory: /sys/devices/virtual/net/${base_device}/mesh/vlan${vid} Information on VLAN devices (base device, vid) necessary to construct the directory path is acquired by parsing /proc/net/vlan/${device}. Where: -${base_device}: the batman device on top of which the VLAN is sitting -${device}: the device interface for the VLAN, -${vid}: the identifier assigned to the VLAN. If the user-selected command is not supported by the VLAN, an appropriate error is shown. Signed-off-by: Marco Dalla Torre <marco.dallato(a)gmail.com> --- Notable changes in V8 -changed displayed error when the default or specified interface is not present from "could not open file '%s': no such file or directory" to "'${device}' is not a valid batman interface" Notable changes in V7 -fixed missing variable initialization -changed free & malloc to realloc -fixed various styling issues -removed unrelated changes Notable changes in V6 -fixed error in string length computation -moved some more variable declarations at the beginning of functions Notable changes in V5 -fixed use of sizeof instead of strlen to compute length of string -use of getline instead of fgets -avoid using fixed-size buffer in 'get_basedev_vid' -moved constant string declarations, local to functions 'get_basedev_vid' and 'handle_sys_setting', from sys.c to sys.h. Now uses #define like other path declarations. -fixed scanf error condition check -fixed malloc error condition check -moved variable declarations at the beginning of functions functions.c | 3 +++ main.c | 2 +- man/batctl.8 | 4 ++-- sys.c | 74 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ sys.h | 3 +++ 5 files changed, 83 insertions(+), 3 deletions(-) diff --git a/functions.c b/functions.c index cc05a48..ed010ea 100644 --- a/functions.c +++ b/functions.c @@ -135,6 +135,9 @@ static void file_open_problem_dbg(char *dir, char *fname, char *full_path) fprintf(stderr, "Error - the folder '/sys/' was not found on the system\n"); fprintf(stderr, "Please make sure that the sys filesystem is properly mounted\n"); return; + } else if (strstr(dir, "/sys/devices/virtual/")) { + fprintf(stderr, "The selected feature '%s' is not supported for vlans\n", fname); + return; } } diff --git a/main.c b/main.c index 24d42fb..bac37ca 100644 --- a/main.c +++ b/main.c @@ -49,7 +49,7 @@ void print_usage(void) fprintf(stderr, "Usage: batctl [options] command|debug table [parameters]\n"); fprintf(stderr, "options:\n"); - fprintf(stderr, " \t-m mesh interface (default 'bat0')\n"); + fprintf(stderr, " \t-m mesh interface or mesh-based VLAN interface (default 'bat0')\n"); fprintf(stderr, " \t-h print this help (or 'batctl <command|debug table> -h' for the parameter help)\n"); fprintf(stderr, " \t-v print version\n"); fprintf(stderr, "\n"); diff --git a/man/batctl.8 b/man/batctl.8 index d04385b..b45cccf 100644 --- a/man/batctl.8 +++ b/man/batctl.8 @@ -42,7 +42,7 @@ behaviour or using the B.A.T.M.A.N. advanced protocol. .SH OPTIONS .TP .I \fBoptions: -\-m specify mesh interface (default 'bat0') +\-m specify mesh interface or a mesh-based VLAN interface (default 'bat0') .br \-h print general batctl help .br @@ -61,7 +61,7 @@ originator interval. The interval is in units of milliseconds. .br .IP "\fBap_isolation\fP|\fBap\fP [\fB0\fP|\fB1\fP]" If no parameter is given the current ap isolation setting is displayed. Otherwise the parameter is used to enable or -disable ap isolation. +disable ap isolation. This command can be used in conjunction with "-m" option to target per VLAN configurations. .br .IP "\fBbridge_loop_avoidance\fP|\fBbl\fP [\fB0\fP|\fB1\fP]" If no parameter is given the current bridge loop avoidance setting is displayed. Otherwise the parameter is used to enable diff --git a/sys.c b/sys.c index b1d7ea8..4eb58be 100644 --- a/sys.c +++ b/sys.c @@ -371,11 +371,62 @@ static void settings_usage(int setting) fprintf(stderr, " \t -h print this help\n"); } +/** + * get_basedev_vid - given a valid VLAN interface, identifies the batman device + * on top of which the VLAN is sitting and its VLAN ID + * @mesh_iface: name of the VLAN network interface + * @base_dev: output argument, pointer to the base device name + * @vid: output argument, pointer to the VLAN ID number + * + * Returns 0 if execution is successful, -1 if an error occurred + */ +static int get_basedev_vid(const char *mesh_iface, char **base_dev, unsigned short *vid) +{ + char *vdev; + char *line_ptr = NULL; + size_t len; + FILE *fp; + int size = strlen(PROC_VLAN_PATH) + strlen(mesh_iface) + 1; + char *fpath = malloc(size); + + if (!fpath) { + fprintf(stderr, "Error - could not allocate path buffer: out of memory ?\n"); + return EXIT_FAILURE; + } + /* prepare path file path: /proc/net/vlan/$mesh_iface*/ + snprintf(fpath, size, "%s%s", PROC_VLAN_PATH, mesh_iface); + fp = fopen(fpath, "r"); + if (!fp) { + fprintf(stderr, "Error - '%s' is not a valid batman interface\n", + mesh_iface); + return EXIT_FAILURE; + } + + if (fscanf(fp, "%ms VID: %hu", &vdev, vid) != 2) + return EXIT_FAILURE; + + *base_dev = NULL; + while (getline(&line_ptr, &len, fp) != -1) { + if (sscanf(line_ptr, "Device: %ms", base_dev) == 1) + break; + } + fclose(fp); + free(line_ptr); + /* handle base device not found case */ + if (!*base_dev) + return EXIT_FAILURE; + + return EXIT_SUCCESS; +} + int handle_sys_setting(char *mesh_iface, int setting, int argc, char **argv) { int optchar, res = EXIT_FAILURE; char *path_buff; const char **ptr; + unsigned short vid; + char *base_dev; + ssize_t path_length; while ((optchar = getopt(argc, argv, "h")) != -1) { switch (optchar) { @@ -392,6 +443,29 @@ int handle_sys_setting(char *mesh_iface, int setting, int argc, char **argv) snprintf(path_buff, PATH_BUFF_LEN, SYS_BATIF_PATH_FMT, mesh_iface); path_buff[PATH_BUFF_LEN - 1] = '\0'; + if (access(path_buff, F_OK) != 0) { + if (errno == ENOENT) { + /* path does not exist, no lan interface: check vlan */ + if (get_basedev_vid(mesh_iface, &base_dev, &vid) == EXIT_FAILURE) + return EXIT_FAILURE; + + path_length = strlen(SYS_VLAN_PATH) + + strlen(base_dev) + + VLAN_ID_MAX_LEN + 1; + path_buff = realloc(path_buff, path_length); + if (!path_buff) { + fprintf(stderr, "Error - could not allocate path buffer: out of memory ?\n"); + return EXIT_FAILURE; + } + snprintf(path_buff, path_length, SYS_VLAN_PATH, + base_dev, vid); + } else if (errno == ENOTDIR) { + /* not a directory, something wrong here */ + fprintf(stderr, "Error - expected directory at '%s'\n", + path_buff); + return EXIT_FAILURE; + } + } if (argc == 1) { res = read_file(path_buff, (char *)batctl_settings[setting].sysfs_name, NO_FLAGS, 0, 0, 0); diff --git a/sys.h b/sys.h index a588e0b..f5df845 100644 --- a/sys.h +++ b/sys.h @@ -30,6 +30,9 @@ #define SYS_IFACE_DIR SYS_IFACE_PATH"/%s/" #define SYS_MESH_IFACE_FMT SYS_IFACE_PATH"/%s/batman_adv/mesh_iface" #define SYS_IFACE_STATUS_FMT SYS_IFACE_PATH"/%s/batman_adv/iface_status" +#define PROC_VLAN_PATH "/proc/net/vlan/" +#define SYS_VLAN_PATH "/sys/devices/virtual/net/%s/mesh/vlan%d/" +#define VLAN_ID_MAX_LEN 4 enum batctl_settings_list { BATCTL_SETTINGS_ORIG_INTERVAL, -- 1.8.3.2

9 years, 8 months

[B.A.T.M.A.N.] [RFC] batctl ping: add IPv6 to ethernet address resolution

by Marco Dalla Torre

Extends the "ping" command available in batctl with the capability of resolving the ethernet link layer (MAC) address from the IPv6 address of any node partecipating the mesh. This is possible by adding to 'batctl' a new set of functions to leverage when performing netlink queries towards the kernel network infrastructure. These new functions, which act as a library, have been inserted into the "bat-mnl.c" and corresponding "bat-mnl.h" files. Such code has been taken from the libmnl library version 1.0.3 with minor modifications. The netlink query is needed to extract the ethernet address, corresponding to the target IPv6 address, from the local neighbor discovery table. If the target address is not initially found in the table, one or more datagram are sent to it to initialize neighbor discovery exchange, just like what already happens for ARP tables in the IPv4 case. Signed-off-by: Marco Dalla Torre <marco.dallato(a)gmail.com> --- Makefile | 2 +- bat-mnl.c | 560 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ bat-mnl.h | 92 ++++++++++ functions.c | 201 +++++++++++++++++++++- 4 files changed, 853 insertions(+), 2 deletions(-) create mode 100644 bat-mnl.c create mode 100644 bat-mnl.h diff --git a/Makefile b/Makefile index 1961298..c62b064 100755 --- a/Makefile +++ b/Makefile @@ -24,7 +24,7 @@ export CONFIG_BATCTL_BISECT=n # batctl build BINARY_NAME = batctl -OBJ = main.o bat-hosts.o functions.o sys.o debug.o ping.o traceroute.o tcpdump.o hash.o debugfs.o ioctl.o list-batman.o translate.o +OBJ = main.o bat-hosts.o functions.o sys.o debug.o ping.o traceroute.o tcpdump.o hash.o debugfs.o ioctl.o list-batman.o translate.o bat-mnl.o OBJ_BISECT = bisect_iv.o MANPAGE = man/batctl.8 diff --git a/bat-mnl.c b/bat-mnl.c new file mode 100644 index 0000000..66190ff --- /dev/null +++ b/bat-mnl.c @@ -0,0 +1,560 @@ +#include <stdlib.h> +#include <string.h> +#include <stdbool.h> +#include <sys/socket.h> +#include <errno.h> + +#include "bat-mnl.h" + +struct mnl_socket { + int fd; + struct sockaddr_nl addr; +}; + +/** + * mnl_nlmsg_get_payload - get a pointer to the payload of the netlink message + * @param nlh pointer to a netlink header + * + * This function returns a pointer to the payload of the netlink message. + */ +void *mnl_nlmsg_get_payload(const struct nlmsghdr *nlh) +{ + return (void *)nlh + MNL_NLMSG_HDRLEN; +} + +static int mnl_cb_noop(__attribute__((unused)) const struct nlmsghdr *nlh, + __attribute__((unused)) void *data) +{ + return MNL_CB_OK; +} + +/** + * mnl_nlmsg_size - calculate the size of Netlink message (without alignment) + * @param len length of the Netlink payload + * + * This function returns the size of a netlink message (header plus payload) + * without alignment. + */ +size_t mnl_nlmsg_size(size_t len) +{ + return len + MNL_NLMSG_HDRLEN; +} + +static int mnl_cb_error(const struct nlmsghdr *nlh, + __attribute__((unused))void *data) +{ + const struct nlmsgerr *err = mnl_nlmsg_get_payload(nlh); + + if (nlh->nlmsg_len < mnl_nlmsg_size(sizeof(struct nlmsgerr))) { + errno = EBADMSG; + return MNL_CB_ERROR; + } + /* Netlink subsystems returns the errno value with different signess */ + if (err->error < 0) + errno = -err->error; + else + errno = err->error; + + return err->error == 0 ? MNL_CB_STOP : MNL_CB_ERROR; +} + +static int mnl_cb_stop(__attribute__((unused)) const struct nlmsghdr *nlh, + __attribute__((unused))void *data) +{ + return MNL_CB_STOP; +} + +static const mnl_cb_t default_cb_array[NLMSG_MIN_TYPE] = { + [NLMSG_NOOP] = mnl_cb_noop, + [NLMSG_ERROR] = mnl_cb_error, + [NLMSG_DONE] = mnl_cb_stop, + [NLMSG_OVERRUN] = mnl_cb_noop, +}; + + +/* TLV iterators */ +/** + * mnl_attr_ok - check if there is room for an attribute in a buffer + * @param attr attribute that we want to check if there is room for + * @param len remaining bytes in a buffer that contains the attribute + * + * This function is used to check that a buffer, which is supposed to contain + * an attribute, has enough room for the attribute that it stores, i.e. this + * function can be used to verify that an attribute is neither malformed nor + * truncated. + * + * This function does not set errno in case of error since it is intended + * for iterations. Thus, it returns 1 on success and 0 on error. + * + * The len parameter may be negative in the case of malformed messages during + * attribute iteration, that is why we use a signed integer. + */ +bool mnl_attr_ok(const struct nlattr *attr, int len) +{ + return len >= (int)sizeof(struct nlattr) && + attr->nla_len >= sizeof(struct nlattr) && + (int)attr->nla_len <= len; +} + +/** + * mnl_attr_next - get the next attribute in the payload of a netlink message + * @param attr pointer to the current attribute + * @param len length of the remaining bytes in the buffer (passed by reference). + * + * This function returns a pointer to the next attribute after the one passed + * as parameter. You have to use mnl_attr_ok() to ensure that the next + * attribute is valid. + */ +struct nlattr *mnl_attr_next(const struct nlattr *attr) +{ + return (struct nlattr *)((void *)attr + MNL_ALIGN(attr->nla_len)); +} + +/** + * mnl_nlmsg_get_payload_tail - get the ending of the netlink message + * @param nlh pointer to netlink message + * + * This function returns a pointer to the netlink message tail. This is useful + * to build a message since we continue adding attributes at the end of the + * message. + */ +void *mnl_nlmsg_get_payload_tail(const struct nlmsghdr *nlh) +{ + return (void *)nlh + MNL_ALIGN(nlh->nlmsg_len); +} + +/** + * mnl_nlmsg_get_payload_offset - get a pointer to the payload of the message + * @param nlh pointer to a netlink header + * @param offset offset to the payload of the attributes TLV set + * + * This function returns a pointer to the payload of the netlink message plus + * a given offset. + */ +void *mnl_nlmsg_get_payload_offset(const struct nlmsghdr *nlh, size_t offset) +{ + return (void *)nlh + MNL_NLMSG_HDRLEN + MNL_ALIGN(offset); +} + + +/** + * mnl_attr_get_type - get type of netlink attribute + * @param attr pointer to netlink attribute + * + * This function returns the attribute type. + */ +uint16_t mnl_attr_get_type(const struct nlattr *attr) +{ + return attr->nla_type & NLA_TYPE_MASK; +} + +/** + * mnl_attr_type_valid - check if the attribute type is valid + * @param attr pointer to attribute to be checked + * @param max maximum attribute type + * + * This function allows to check if the attribute type is higher than the + * maximum supported type. If the attribute type is invalid, this function + * returns -1 and errno is explicitly set. On success, this function returns 1. + * + * Strict attribute checking in user-space is not a good idea since you may + * run an old application with a newer kernel that supports new attributes. + * This leads to backward compatibility breakages in user-space. Better check + * if you support an attribute, if not, skip it. + */ +int mnl_attr_type_valid(const struct nlattr *attr, uint16_t max) +{ + if (mnl_attr_get_type(attr) > max) { + errno = EOPNOTSUPP; + return -1; + } + return 1; +} + +/** + * mnl_attr_parse - parse attributes + * @param nlh pointer to netlink message + * @param offset offset to start parsing from (if payload is after any header) + * @param cb callback function that is called for each attribute + * @param data pointer to data that is passed to the callback function + * + * This function allows to iterate over the sequence of attributes that compose + * the Netlink message. You can then put the attribute in an array as it + * usually happens at this stage or you can use any other data structure (such + * as lists or trees). + * + * This function propagates the return value of the callback, which can be + * MNL_CB_ERROR, MNL_CB_OK or MNL_CB_STOP. + */ +int +mnl_attr_parse(const struct nlmsghdr *nlh, unsigned int offset, + mnl_attr_cb_t cb, void *data) +{ + int ret = MNL_CB_OK; + const struct nlattr *attr; + + mnl_attr_for_each(attr, nlh, offset) { + ret = cb(attr, data); + if (ret <= MNL_CB_STOP) + return ret; + } + return ret; +} + +/** + * mnl_nlmsg_put_extra_header - reserve and prepare room for an extra header + * @param nlh pointer to Netlink header + * @param size size of the extra header that we want to put + * + * This function sets to zero the room that is required to put the extra + * header after the initial Netlink header. This function also increases + * the nlmsg_len field. You have to invoke mnl_nlmsg_put_header() before + * you call this function. This function returns a pointer to the extra + * header. + */ +void * +mnl_nlmsg_put_extra_header(struct nlmsghdr *nlh, size_t size) +{ + char *ptr = (char *)nlh + nlh->nlmsg_len; + size_t len = MNL_ALIGN(size); + nlh->nlmsg_len += len; + memset(ptr, 0, len); + return ptr; +} + +/** + * mnl_nlmsg_put_header - reserve and prepare room for Netlink header + * @param buf memory already allocated to store the Netlink header + * + * This function sets to zero the room that is required to put the Netlink + * header in the memory buffer passed as parameter. This function also + * initializes the nlmsg_len field to the size of the Netlink header. This + * function returns a pointer to the Netlink header structure. + */ +struct nlmsghdr *mnl_nlmsg_put_header(void *buf) +{ + int len = MNL_ALIGN(sizeof(struct nlmsghdr)); + struct nlmsghdr *nlh = buf; + + memset(buf, 0, len); + nlh->nlmsg_len = len; + return nlh; +} + +/** + * mnl_socket_open - open a netlink socket + * @param bus the netlink socket bus ID (see NETLINK_* constants) + * + * On error, it returns -1 and errno is appropriately set. Otherwise, it + * returns a valid pointer to the mnl_socket structure. + */ +struct mnl_socket *mnl_socket_open(int bus) +{ + struct mnl_socket *nl; + + nl = calloc(sizeof(struct mnl_socket), 1); + if (nl == NULL) + return NULL; + + nl->fd = socket(AF_NETLINK, SOCK_RAW, bus); + if (nl->fd == -1) { + free(nl); + return NULL; + } + + return nl; +} + +/** + * mnl_socket_bind - bind netlink socket + * @param nl netlink socket obtained via mnl_socket_open() + * @param groups the group of message you're interested in + * @param pid the port ID you want to use (use zero for automatic selection) + * + * On error, this function returns -1 and errno is appropriately set. On + * success, 0 is returned. You can use MNL_SOCKET_AUTOPID which is 0 for + * automatic port ID selection. + */ +int mnl_socket_bind(struct mnl_socket *nl, unsigned int groups, pid_t pid) +{ + int ret; + socklen_t addr_len; + + nl->addr.nl_family = AF_NETLINK; + nl->addr.nl_groups = groups; + nl->addr.nl_pid = pid; + + ret = bind(nl->fd, (struct sockaddr *) &nl->addr, sizeof(nl->addr)); + if (ret < 0) + return ret; + + addr_len = sizeof(nl->addr); + ret = getsockname(nl->fd, (struct sockaddr *) &nl->addr, &addr_len); + if (ret < 0) + return ret; + + if (addr_len != sizeof(nl->addr)) { + errno = EINVAL; + return -1; + } + if (nl->addr.nl_family != AF_NETLINK) { + errno = EINVAL; + return -1; + } + return 0; +} + +/** + * mnl_socket_get_portid - obtain Netlink PortID from netlink socket + * @param nl netlink socket obtained via mnl_socket_open() + * + * This function returns the Netlink PortID of a given netlink socket. + * It's a common mistake to assume that this PortID equals the process ID + * which is not always true. This is the case if you open more than one + * socket that is binded to the same Netlink subsystem from the same process. + */ +unsigned int mnl_socket_get_portid(const struct mnl_socket *nl) +{ + return nl->addr.nl_pid; +} + +/** + * mnl_socket_sendto - send a netlink message of a certain size + * @param nl netlink socket obtained via mnl_socket_open() + * @param buf buffer containing the netlink message to be sent + * @param len number of bytes in the buffer that you want to send + * + * On error, it returns -1 and errno is appropriately set. Otherwise, it + * returns the number of bytes sent. + */ +ssize_t +mnl_socket_sendto(const struct mnl_socket *nl, const void *buf, size_t len) +{ + static const struct sockaddr_nl snl = { + .nl_family = AF_NETLINK + }; + return sendto(nl->fd, buf, len, 0, + (struct sockaddr *) &snl, sizeof(snl)); +} + +/** + * mnl_socket_recvfrom - receive a netlink message + * @param nl netlink socket obtained via mnl_socket_open() + * @param buf buffer that you want to use to store the netlink message + * @param bufsiz size of the buffer passed to store the netlink message + * + * On error, it returns -1 and errno is appropriately set. If errno is set + * to ENOSPC, it means that the buffer that you have passed to store the + * netlink message is too small, so you have received a truncated message. + * To avoid this, you have to allocate a buffer of MNL_SOCKET_BUFFER_SIZE + * (which is 8KB, see linux/netlink.h for more information). Using this + * buffer size ensures that your buffer is big enough to store the netlink + * message without truncating it. + */ +ssize_t +mnl_socket_recvfrom(const struct mnl_socket *nl, void *buf, size_t bufsiz) +{ + ssize_t ret; + struct sockaddr_nl addr; + struct iovec iov = { + .iov_base = buf, + .iov_len = bufsiz, + }; + struct msghdr msg = { + .msg_name = &addr, + .msg_namelen = sizeof(struct sockaddr_nl), + .msg_iov = &iov, + .msg_iovlen = 1, + .msg_control = NULL, + .msg_controllen = 0, + .msg_flags = 0, + }; + ret = recvmsg(nl->fd, &msg, 0); + if (ret == -1) + return ret; + + if (msg.msg_flags & MSG_TRUNC) { + errno = ENOSPC; + return -1; + } + if (msg.msg_namelen != sizeof(struct sockaddr_nl)) { + errno = EINVAL; + return -1; + } + return ret; +} + +/** + * mnl_nlmsg_portid_ok - perform portID origin check + * @param nlh current netlink message that we are handling + * @param portid netlink portid that we want to check + * + * This functions returns true if the origin is fulfilled, otherwise + * false is returned. We skip the tracking for netlink message whose portID + * is zero since it is reserved for event-based kernel notifications. On the + * other hand, if portid is set but the message PortID is not (i.e. this + * is an event message coming from kernel-space), then we also skip the + * tracking. This approach is good if we use the same socket to send commands + * to kernel-space (that we want to track) and to listen to events (that we + * do not track). + */ +bool +mnl_nlmsg_portid_ok(const struct nlmsghdr *nlh, unsigned int portid) +{ + return nlh->nlmsg_pid && portid ? nlh->nlmsg_pid == portid : true; +} + +/** + * mnl_nlmsg_ok - check a there is room for netlink message + * @param nlh netlink message that we want to check + * @param len remaining bytes in a buffer that contains the netlink message + * + * This function is used to check that a buffer that contains a netlink + * message has enough room for the netlink message that it stores, ie. this + * function can be used to verify that a netlink message is not malformed nor + * truncated. + * + * This function does not set errno in case of error since it is intended + * for iterations. Thus, it returns 1 on success and 0 on error. + * + * The len parameter may become negative in malformed messages during message + * iteration, that is why we use a signed integer. + */ +bool mnl_nlmsg_ok(const struct nlmsghdr *nlh, int len) +{ + return len >= (int)sizeof(struct nlmsghdr) && + nlh->nlmsg_len >= sizeof(struct nlmsghdr) && + (int)nlh->nlmsg_len <= len; +} + +/** + * mnl_nlmsg_next - get the next netlink message in a multipart message + * @param nlh current netlink message that we are handling + * @param len length of the remaining bytes in the buffer (passed by reference). + * + * This function returns a pointer to the next netlink message that is part + * of a multi-part netlink message. Netlink can batch several messages into + * one buffer so that the receiver has to iterate over the whole set of + * Netlink messages. + * + * You have to use mnl_nlmsg_ok() to check if the next Netlink message is + * valid. + */ +struct nlmsghdr * +mnl_nlmsg_next(const struct nlmsghdr *nlh, int *len) +{ + *len -= MNL_ALIGN(nlh->nlmsg_len); + return (struct nlmsghdr *)((void *)nlh + MNL_ALIGN(nlh->nlmsg_len)); +} + +/** + * mnl_nlmsg_seq_ok - perform sequence tracking + * @param nlh current netlink message that we are handling + * @param seq last sequence number used to send a message + * + * This functions returns true if the sequence tracking is fulfilled, otherwise + * false is returned. We skip the tracking for netlink messages whose sequence + * number is zero since it is usually reserved for event-based kernel + * notifications. On the other hand, if seq is set but the message sequence + * number is not set (i.e. this is an event message coming from kernel-space), + * then we also skip the tracking. This approach is good if we use the same + * socket to send commands to kernel-space (that we want to track) and to + * listen to events (that we do not track). + */ +bool +mnl_nlmsg_seq_ok(const struct nlmsghdr *nlh, unsigned int seq) +{ + return nlh->nlmsg_seq && seq ? nlh->nlmsg_seq == seq : true; +} + +static inline int +__mnl_cb_run(const void *buf, size_t numbytes, unsigned int seq, + unsigned int portid, mnl_cb_t cb_data, void *data, + mnl_cb_t *cb_ctl_array, unsigned int cb_ctl_array_len) +{ + int ret = MNL_CB_OK, len = numbytes; + const struct nlmsghdr *nlh = buf; + + while (mnl_nlmsg_ok(nlh, len)) { + /* check message source */ + if (!mnl_nlmsg_portid_ok(nlh, portid)) { + errno = ESRCH; + return -1; + } + /* perform sequence tracking */ + if (!mnl_nlmsg_seq_ok(nlh, seq)) { + errno = EPROTO; + return -1; + } + + /* dump was interrupted */ + if (nlh->nlmsg_flags & NLM_F_DUMP_INTR) { + errno = EINTR; + return -1; + } + + /* netlink data message handling */ + if (nlh->nlmsg_type >= NLMSG_MIN_TYPE) { + if (cb_data) { + ret = cb_data(nlh, data); + if (ret <= MNL_CB_STOP) + goto out; + } + } else if (nlh->nlmsg_type < cb_ctl_array_len) { + if (cb_ctl_array && cb_ctl_array[nlh->nlmsg_type]) { + ret = cb_ctl_array[nlh->nlmsg_type](nlh, data); + if (ret <= MNL_CB_STOP) + goto out; + } + } else if (default_cb_array[nlh->nlmsg_type]) { + ret = default_cb_array[nlh->nlmsg_type](nlh, data); + if (ret <= MNL_CB_STOP) + goto out; + } + nlh = mnl_nlmsg_next(nlh, &len); + } +out: + return ret; +} + +/** + * mnl_cb_run - callback runqueue for netlink messages (simplified version) + * @param buf buffer that contains the netlink messages + * @param numbytes number of bytes stored in the buffer + * @param seq sequence number that we expect to receive + * @param portid Netlink PortID that we expect to receive + * @param cb_data callback handler for data messages + * @param data pointer to data that will be passed to the data callback handler + * + * This function is like mnl_cb_run2() but it does not allow you to set + * the control callback handlers. + * + * Your callback may return three possible values: + * - MNL_CB_ERROR (<=-1): an error has occurred. Stop callback runqueue. + * - MNL_CB_STOP (=0): stop callback runqueue. + * - MNL_CB_OK (>=1): no problems has occurred. + * + * This function propagates the callback return value. + */ +int +mnl_cb_run(const void *buf, size_t numbytes, unsigned int seq, + unsigned int portid, mnl_cb_t cb_data, void *data) +{ + return __mnl_cb_run(buf, numbytes, seq, portid, cb_data, data, NULL, 0); +} + + +/** + * mnl_socket_close - close a given netlink socket + * @param nl netlink socket obtained via mnl_socket_open() + * + * On error, this function returns -1 and errno is appropriately set. + * On success, it returns 0. + */ +int mnl_socket_close(struct mnl_socket *nl) +{ + int ret = close(nl->fd); + free(nl); + return ret; +} + diff --git a/bat-mnl.h b/bat-mnl.h new file mode 100644 index 0000000..255b568 --- /dev/null +++ b/bat-mnl.h @@ -0,0 +1,92 @@ +#ifndef _BATMNL_H_ +#define _BATMNL_H_ + +#include <unistd.h> +#include <stdint.h> +#include <linux/netlink.h> +#include <linux/rtnetlink.h> + +/* + * Netlink socket API + */ +#define MNL_SOCKET_AUTOPID 0 +#define MNL_SOCKET_BUFFER_SIZE (getpagesize() < 8192L ? getpagesize() : 8192L) + +/* + * nla_type (16 bits) + * +---+---+-------------------------------+ + * | N | O | Attribute Type | + * +---+---+-------------------------------+ + * N := Carries nested attributes + * O := Payload stored in network byte order + * + * Note: The N and O flag are mutually exclusive. + */ +#define NLA_F_NESTED (1 << 15) +#define NLA_F_NET_BYTEORDER (1 << 14) +#define NLA_TYPE_MASK ~(NLA_F_NESTED | NLA_F_NET_BYTEORDER) + +struct mnl_socket; + +extern struct mnl_socket *mnl_socket_open(int type); +extern int mnl_socket_bind(struct mnl_socket *nl, + unsigned int groups, pid_t pid); +extern int mnl_socket_close(struct mnl_socket *nl); +extern unsigned int mnl_socket_get_portid(const struct mnl_socket *nl); +extern ssize_t mnl_socket_sendto(const struct mnl_socket *nl, + const void *req, size_t siz); +extern ssize_t mnl_socket_recvfrom(const struct mnl_socket *nl, void *buf, + size_t siz); + +/* + * Netlink message API + */ +#define MNL_ALIGNTO 4 +#define MNL_ALIGN(len) (((len)+MNL_ALIGNTO-1) & ~(MNL_ALIGNTO-1)) +#define MNL_NLMSG_HDRLEN MNL_ALIGN(sizeof(struct nlmsghdr)) + + +/* + * callback API + */ + +#define MNL_CB_ERROR -1 +#define MNL_CB_STOP 0 +#define MNL_CB_OK 1 + +typedef int (*mnl_cb_t)(const struct nlmsghdr *nlh, void *data); + +extern int mnl_cb_run(const void *buf, size_t numbytes, unsigned int seq, + unsigned int portid, mnl_cb_t cb_data, void *data); + +/* TLV callback-based attribute parsers */ +typedef int (*mnl_attr_cb_t)(const struct nlattr *attr, void *data); + +extern int mnl_attr_parse(const struct nlmsghdr *nlh, unsigned int offset, + mnl_attr_cb_t cb, void *data); + + +#define mnl_attr_for_each(attr, nlh, offset) \ + for ((attr) = mnl_nlmsg_get_payload_offset((nlh), (offset)); \ + mnl_attr_ok((attr), (char *)mnl_nlmsg_get_payload_tail( \ + nlh) - (char *)(attr)); \ + (attr) = mnl_attr_next(attr)) + + +/* Netlink message getters */ +extern void *mnl_nlmsg_get_payload(const struct nlmsghdr *nlh); +extern void *mnl_nlmsg_get_payload_offset(const struct nlmsghdr *nlh, + size_t offset); +extern void *mnl_nlmsg_get_payload_tail(const struct nlmsghdr *nlh); + +/* TLV attribute getters */ +extern uint16_t mnl_attr_get_type(const struct nlattr *attr); + +/* TLV validation */ +extern int mnl_attr_type_valid(const struct nlattr *attr, uint16_t maxtype); + +/* Netlink message header builder */ +extern struct nlmsghdr *mnl_nlmsg_put_header(void *buf); +extern void *mnl_nlmsg_put_extra_header(struct nlmsghdr *nlh, size_t size); + +#endif diff --git a/functions.c b/functions.c index cc05a48..098a6eb 100644 --- a/functions.c +++ b/functions.c @@ -34,14 +34,19 @@ #include <errno.h> #include <fcntl.h> #include <sys/time.h> +#include <time.h> #include "main.h" #include "functions.h" +#include "bat-mnl.h" #include "bat-hosts.h" #include "sys.h" #include "debug.h" #include "debugfs.h" + +#define CB_FINISH -2 + static struct timeval start_time; static char *host_name; char *line_ptr = NULL; @@ -413,6 +418,29 @@ out: return mac_result; } +static struct in6_addr *resolve_ipv6(const char *asc) +{ + int ret; + struct addrinfo hints; + struct addrinfo *res; + struct sockaddr_in6 *inet; + struct in6_addr *addr; + + memset(&hints, 0, sizeof(hints)); + hints.ai_family = AF_INET6; + ret = getaddrinfo(asc, NULL, &hints, &res); + if (ret) + return 0; + + if (res) { + inet = (struct sockaddr_in6 *)res->ai_addr; + addr = &(inet->sin6_addr); + } + + freeaddrinfo(res); + return addr; +} + static uint32_t resolve_ipv4(const char *asc) { int ret; @@ -436,6 +464,32 @@ static uint32_t resolve_ipv4(const char *asc) return addr; } +/* + * Sends a datagram to the given IPv6 address in order to spawn a neighbor + * discovery exchange. If the address is correctly resolved, then the + * neighbor discovery table will carry the corresponding link layer address. + * + * @addr: target IPv6 address for the link layer resolution + */ +static void request_nd(struct in6_addr *addr) +{ + struct sockaddr_in6 inet; + int sock; + char t = 0; + + memset(&inet, 0, sizeof(inet)); + sock = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP); + if (sock < 0) + return; + + inet.sin6_family = AF_INET6; + inet.sin6_port = htons(9); + memcpy(&(inet.sin6_addr), addr, sizeof(struct in6_addr)); + sendto(sock, &t, sizeof(t), 0, (const struct sockaddr *)&inet, + sizeof(inet)); + close(sock); +} + static void request_arp(uint32_t ipv4_addr) { struct sockaddr_in inet4; @@ -455,6 +509,131 @@ static void request_arp(uint32_t ipv4_addr) close(sock); } +/* + * Data structure used to hold input and output data for/from netlink + * neighbor discovery query callback function + */ +struct ipv6_lladdr { + const struct in6_addr *ip6_addr; + struct ether_addr *ll_addr; +}; + +/* + * Callback function called during netlink message parsing. Popolates the array + * obtained in input with parsed elements from each netlink attribute found in + * the payload message. + * @attr: message current attribute + * @data: array to populate + * + * @return outcome of attribute parsing + */ +static int data_attr_cb(const struct nlattr *attr, void *data) +{ + const struct nlattr **tb = data; + int type = mnl_attr_get_type(attr); + + /* skip unsupported attribute in user-space */ + if (mnl_attr_type_valid(attr, NDA_MAX) < 0) + return MNL_CB_OK; + tb[type] = attr; + return MNL_CB_OK; +} + +/* + * Callback function, called on every netlink packet received in response + * of the query. + */ +static int data_cb_neigh(const struct nlmsghdr *nlh, void *data) +{ + struct rtattr *tb[NDA_MAX+1] = {}; + struct ndmsg *ndm = mnl_nlmsg_get_payload(nlh); + struct ipv6_lladdr *inout = data; + + if (ndm->ndm_family != AF_INET6 && + (ndm->ndm_state != NUD_REACHABLE + || ndm->ndm_state != NUD_STALE)) { + return MNL_CB_OK; + } + + mnl_attr_parse(nlh, sizeof(*ndm), data_attr_cb, tb); + + if (!tb[NDA_LLADDR] || !tb[NDA_DST]) + return MNL_CB_OK; + + if (RTA_PAYLOAD(tb[NDA_DST]) != sizeof(struct in6_addr)) + return MNL_CB_OK; + + if (memcmp(inout->ip6_addr, + RTA_DATA(tb[NDA_DST]), sizeof(struct in6_addr)) == 0) { + inout->ll_addr = malloc(sizeof(struct ether_addr)); + memcpy(inout->ll_addr, + RTA_DATA(tb[NDA_LLADDR]), RTA_PAYLOAD(tb[NDA_LLADDR])); + return CB_FINISH; + } + return MNL_CB_OK; +} + +/* + * Queries the kernel for the link layer (ethernet) address corresponding to + * the given IPv6 address. + * @in6_addr: address that needs to be resolved + * + * Returns the ethernet address if found, NULL otherwise + */ +static struct ether_addr *resolve_mac_nd(const struct in6_addr *addr) +{ + struct mnl_socket *nl; + char buf[MNL_SOCKET_BUFFER_SIZE]; + struct nlmsghdr *nlh; + struct ndmsg *ndm; + int ret; + unsigned int seq, portid; + + struct ipv6_lladdr inout = { + .ip6_addr = addr, + .ll_addr = NULL + }; + + nlh = mnl_nlmsg_put_header(buf); + nlh->nlmsg_type = RTM_GETNEIGH; /*RTM_GETNEIGHTBL RTM_GETNEIGH*/ + nlh->nlmsg_flags = NLM_F_REQUEST | NLM_F_DUMP; + nlh->nlmsg_seq = seq = time(NULL); + ndm = mnl_nlmsg_put_extra_header(nlh, sizeof(*ndm)); + ndm->ndm_family = AF_INET6; + + nl = mnl_socket_open(NETLINK_ROUTE); + if (nl == NULL) { + perror("mnl_socket_open"); + exit(EXIT_FAILURE); + } + if (mnl_socket_bind(nl, 0, MNL_SOCKET_AUTOPID) < 0) { + perror("mnl_socket_bind"); + exit(EXIT_FAILURE); + } + portid = mnl_socket_get_portid(nl); + + if (mnl_socket_sendto(nl, nlh, nlh->nlmsg_len) < 0) { + perror("mnl_socket_send"); + exit(EXIT_FAILURE); + } + ret = mnl_socket_recvfrom(nl, buf, sizeof(buf)); + + while (ret > 0) { + ret = mnl_cb_run(buf, ret, seq, portid, data_cb_neigh, &inout); + if (ret <= MNL_CB_STOP) + break; + ret = mnl_socket_recvfrom(nl, buf, sizeof(buf)); + } + if (ret == MNL_CB_ERROR) { + perror("error"); + exit(EXIT_FAILURE); + } + mnl_socket_close(nl); + + return inout.ll_addr; +} + + static struct ether_addr *resolve_mac_from_arp(uint32_t ipv4_addr) { struct ether_addr mac_empty; @@ -524,6 +703,25 @@ static struct ether_addr *resolve_mac_from_arp(uint32_t ipv4_addr) return mac_result; } +static struct ether_addr *resolve_mac_from_ipv6(const char *asc) +{ + struct in6_addr *addr; + int retries = 5; + struct ether_addr *mac_result = NULL; + addr = resolve_ipv6(asc); + if (!addr) + return NULL; + + while (retries-- && !mac_result) { + mac_result = resolve_mac_nd(addr); + if (!mac_result) { + request_nd(addr); + usleep(200000); + } + } + return mac_result; +} + static struct ether_addr *resolve_mac_from_ipv4(const char *asc) { uint32_t ipv4_addr; @@ -554,7 +752,8 @@ struct ether_addr *resolve_mac(const char *asc) goto out; mac_result = resolve_mac_from_ipv4(asc); - + if (!mac_result) + mac_result = resolve_mac_from_ipv6(asc); out: return mac_result; } -- 1.8.3.2

9 years, 8 months

[B.A.T.M.A.N.] [PATCHv7] batctl: add sys framework for VLAN support

by Marco Dalla Torre

Allow the batctl tool to take advantage of changes from commit e4ff5c153dab054a6cd1c4132f87bc5e77127456 "add sys framework for VLAN" recently added to batman-adv, so that users can execute commands in a per VLAN fashion. If no directory entry corresponding to the user-selected device is found at the standard location for non VLAN interfaces (/sys/class/net/${device}/mesh/), 'batctl' now looks into directory: /sys/devices/virtual/net/${base_device}/mesh/vlan${vid} Information on VLAN devices (base device, vid) necessary to construct the directory path is acquired by parsing /proc/net/vlan/${device}. Where: -${base_device}: the batman device on top of which the VLAN is sitting -${device}: the device interface for the VLAN, -${vid}: the identifier assigned to the VLAN. If the user-selected command is not supported by the VLAN, an appropriate error is shown. Signed-off-by: Marco Dalla Torre <marco.dallato(a)gmail.com> --- Notable changes in V7 -fixed missing variable initialization -changed free & malloc to realloc -fixed various styling issues -removed unrelated changes Notable changes in V6 -fixed error in string length computation -moved some more variable declarations at the beginning of functions Notable changes in V5 -fixed use of sizeof instead of strlen to compute length of string -use of getline instead of fgets -avoid using fixed-size buffer in 'get_basedev_vid' -moved constant string declarations, local to functions 'get_basedev_vid' and 'handle_sys_setting', from sys.c to sys.h. Now uses #define like other path declarations. -fixed scanf error condition check -fixed malloc error condition check -moved variable declarations at the beginning of functions functions.c | 3 +++ main.c | 2 +- man/batctl.8 | 4 ++-- sys.c | 75 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ sys.h | 3 +++ 5 files changed, 84 insertions(+), 3 deletions(-) diff --git a/functions.c b/functions.c index cc05a48..ed010ea 100644 --- a/functions.c +++ b/functions.c @@ -135,6 +135,9 @@ static void file_open_problem_dbg(char *dir, char *fname, char *full_path) fprintf(stderr, "Error - the folder '/sys/' was not found on the system\n"); fprintf(stderr, "Please make sure that the sys filesystem is properly mounted\n"); return; + } else if (strstr(dir, "/sys/devices/virtual/")) { + fprintf(stderr, "The selected feature '%s' is not supported for vlans\n", fname); + return; } } diff --git a/main.c b/main.c index 24d42fb..bac37ca 100644 --- a/main.c +++ b/main.c @@ -49,7 +49,7 @@ void print_usage(void) fprintf(stderr, "Usage: batctl [options] command|debug table [parameters]\n"); fprintf(stderr, "options:\n"); - fprintf(stderr, " \t-m mesh interface (default 'bat0')\n"); + fprintf(stderr, " \t-m mesh interface or mesh-based VLAN interface (default 'bat0')\n"); fprintf(stderr, " \t-h print this help (or 'batctl <command|debug table> -h' for the parameter help)\n"); fprintf(stderr, " \t-v print version\n"); fprintf(stderr, "\n"); diff --git a/man/batctl.8 b/man/batctl.8 index d04385b..b45cccf 100644 --- a/man/batctl.8 +++ b/man/batctl.8 @@ -42,7 +42,7 @@ behaviour or using the B.A.T.M.A.N. advanced protocol. .SH OPTIONS .TP .I \fBoptions: -\-m specify mesh interface (default 'bat0') +\-m specify mesh interface or a mesh-based VLAN interface (default 'bat0') .br \-h print general batctl help .br @@ -61,7 +61,7 @@ originator interval. The interval is in units of milliseconds. .br .IP "\fBap_isolation\fP|\fBap\fP [\fB0\fP|\fB1\fP]" If no parameter is given the current ap isolation setting is displayed. Otherwise the parameter is used to enable or -disable ap isolation. +disable ap isolation. This command can be used in conjunction with "-m" option to target per VLAN configurations. .br .IP "\fBbridge_loop_avoidance\fP|\fBbl\fP [\fB0\fP|\fB1\fP]" If no parameter is given the current bridge loop avoidance setting is displayed. Otherwise the parameter is used to enable diff --git a/sys.c b/sys.c index b1d7ea8..517be03 100644 --- a/sys.c +++ b/sys.c @@ -371,11 +371,63 @@ static void settings_usage(int setting) fprintf(stderr, " \t -h print this help\n"); } +/** + * get_basedev_vid - given a valid VLAN interface, identifies the batman device + * on top of which the VLAN is sitting and its VLAN ID + * @mesh_iface: name of the VLAN network interface + * @base_dev: output argument, pointer to the base device name + * @vid: output argument, pointer to the VLAN ID number + * + * Returns 0 if execution is successful, -1 if an error occurred + */ +static int get_basedev_vid(const char *mesh_iface, char **base_dev, unsigned short *vid) +{ + char *vdev; + char *line_ptr = NULL; + size_t len; + FILE *fp; + int size = strlen(PROC_VLAN_PATH) + strlen(mesh_iface) + 1; + char *fpath = malloc(size); + + if (!fpath) { + fprintf(stderr, "Error - could not allocate path buffer: out of memory ?\n"); + return EXIT_FAILURE; + } + /* prepare path file path: /proc/net/vlan/$mesh_iface*/ + snprintf(fpath, size, "%s%s", PROC_VLAN_PATH, mesh_iface); + + fp = fopen(fpath, "r"); + if (!fp) { + fprintf(stderr, "Error - could not open file '%s': %s\n", + fpath, strerror(errno)); + return EXIT_FAILURE; + } + + if (fscanf(fp, "%ms VID: %hu", &vdev, vid) != 2) + return EXIT_FAILURE; + + *base_dev = NULL; + while (getline(&line_ptr, &len, fp) != -1) { + if (sscanf(line_ptr, "Device: %ms", base_dev) == 1) + break; + } + fclose(fp); + free(line_ptr); + /* handle base device not found case */ + if (!*base_dev) + return EXIT_FAILURE; + + return EXIT_SUCCESS; +} + int handle_sys_setting(char *mesh_iface, int setting, int argc, char **argv) { int optchar, res = EXIT_FAILURE; char *path_buff; const char **ptr; + unsigned short vid; + char *base_dev; + ssize_t path_length; while ((optchar = getopt(argc, argv, "h")) != -1) { switch (optchar) { @@ -392,6 +444,29 @@ int handle_sys_setting(char *mesh_iface, int setting, int argc, char **argv) snprintf(path_buff, PATH_BUFF_LEN, SYS_BATIF_PATH_FMT, mesh_iface); path_buff[PATH_BUFF_LEN - 1] = '\0'; + if (access(path_buff, F_OK) != 0) { + if (errno == ENOENT) { + /* path does not exist, no lan interface: check vlan */ + if (get_basedev_vid(mesh_iface, &base_dev, &vid) == EXIT_FAILURE) + return EXIT_FAILURE; + + path_length = strlen(SYS_VLAN_PATH) + + strlen(base_dev) + + VLAN_ID_MAX_LEN + 1; + path_buff = realloc(path_buff, path_length); + if (!path_buff) { + fprintf(stderr, "Error - could not allocate path buffer: out of memory ?\n"); + return EXIT_FAILURE; + } + snprintf(path_buff, path_length, SYS_VLAN_PATH, + base_dev, vid); + } else if (errno == ENOTDIR) { + /* not a directory, something wrong here */ + fprintf(stderr, "Error - expected directory at '%s'\n", + path_buff); + return EXIT_FAILURE; + } + } if (argc == 1) { res = read_file(path_buff, (char *)batctl_settings[setting].sysfs_name, NO_FLAGS, 0, 0, 0); diff --git a/sys.h b/sys.h index a588e0b..f5df845 100644 --- a/sys.h +++ b/sys.h @@ -30,6 +30,9 @@ #define SYS_IFACE_DIR SYS_IFACE_PATH"/%s/" #define SYS_MESH_IFACE_FMT SYS_IFACE_PATH"/%s/batman_adv/mesh_iface" #define SYS_IFACE_STATUS_FMT SYS_IFACE_PATH"/%s/batman_adv/iface_status" +#define PROC_VLAN_PATH "/proc/net/vlan/" +#define SYS_VLAN_PATH "/sys/devices/virtual/net/%s/mesh/vlan%d/" +#define VLAN_ID_MAX_LEN 4 enum batctl_settings_list { BATCTL_SETTINGS_ORIG_INTERVAL, -- 1.8.3.2

9 years, 8 months

[B.A.T.M.A.N.] batctl: Debian patches for 2013.3.0-2

by Sven Eckelmann

Hi, different patches [1] were aggregated in the Debian package of batctl 2013.3.0-2. These were not made against the current master but rebased versions are included in this thread. Kind regards, Sven [1] http://anonscm.debian.org/gitweb/?p=collab-maint/batctl.git;a=tree;f=debian…

9 years, 8 months

[B.A.T.M.A.N.] Fwd: Re: Hamburg freifunk geekend02

by Nicolás Echániz

I'm forwarding this e-mail to the list per request of Andre. -------- Mensaje original -------- Asunto: Re: [B.A.T.M.A.N.] Hamburg freifunk geekend02 Fecha: Wed, 11 Sep 2013 10:18:09 +0200 De: Andre Schmidt <m.andre.schmidt(a)me.com> A: nicoechaniz(a)altermundi.net <nicoechaniz(a)altermundi.net> A filter on the list rejects my answer, so I can only answer to you. Maybe you can forward it to the list, in case others care as well. thanks Hi Nico, By physically connected you mean wireless mesh and by VPN you mean cable-based VPN over the internet? Mostly the latter, but it is mixed. You can check out our node graph [0] to get an impression of the topology. See you in Berlin, andre [0] http://knotengraph.de <http://knotengraph.de> Am 11.09.2013 um 10:00 schrieb Nicolás Echániz <nicoechaniz(a)altermundi.net <mailto:nicoechaniz@altermundi.net>>: > El 07/09/13 06:38, Andre Schmidt escribió: >> Hi there, >> >> Sep. 27.-29., 2013, we'll meet up for geekend02 [0] at Bürgerhaus >> Hamburg-Eidelstedt, Germany. This is going to be a great opportunity >> to meet AFK. Naturally, you can bring your own keyboard, so it's all >> good, don't worry. >> >> Since Hamburg is probably one of the larger B.A.T.M.A.N. networks on >> this planet w/ 300+ routers constantly online and still growing >> rapidly, we do fear that we'll run into scaling problems sooner or >> later. Therefore, your expertise on how to counteract is very >> welcome. > > sounds very interesting, please document :) > > are this 300+ routers physically connected or is it mostly VPN? > > hope to meet some of you during the summit in Berlin and to hear more > about your conclusions regarding scalability. > > > cheers, > Nico >

9 years, 8 months

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B.A.T.M.A.N September 2013