IPv4 addresses and hostnames are easier to remember than many MAC addresses. batctl can automatically resolve the MAC address of the target device when the IP is configured on top of the batman-adv device and the source and destination batman-adv interface are in the same IPv4 subnet.
Signed-off-by: Sven Eckelmann sven@narfation.org --- Fixed some printf-strings
README | 4 +- functions.c | 149 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ functions.h | 1 + man/batctl.8 | 18 ++++--- ping.c | 6 +-- traceroute.c | 6 +-- 6 files changed, 170 insertions(+), 14 deletions(-)
diff --git a/README b/README index 37e7514..809ab3d 100644 --- a/README +++ b/README @@ -81,7 +81,7 @@ batctl ping
Sends a Layer 2 batman-adv ping to check round trip time and connectivity
-Usage: batctl ping [parameters] mac|bat-host +Usage: batctl ping [parameters] mac|bat-host|host-name|IPv4-address parameters: -c ping packet count -h print this help @@ -107,7 +107,7 @@ batctl traceroute Traceroute sends 3 packets to each hop, awaits the answers and prints out the response times.
-Usage: batctl traceroute [parameters] mac|bat-host +Usage: batctl traceroute [parameters] mac|bat-host|host-name|IPv4-address
Example:
diff --git a/functions.c b/functions.c index 090341d..7bec322 100644 --- a/functions.c +++ b/functions.c @@ -22,6 +22,9 @@
#define _GNU_SOURCE #include <netinet/ether.h> +#include <arpa/inet.h> +#include <sys/socket.h> +#include <netdb.h> #include <sys/types.h> #include <sys/stat.h> #include <unistd.h> @@ -400,3 +403,149 @@ out: free(line); return mac_result; } + +static uint32_t resolve_ipv4(const char *asc) +{ + int ret; + struct addrinfo hints; + struct addrinfo *res; + struct sockaddr_in *inet4; + uint32_t addr = 0; + + memset(&hints, 0, sizeof(hints)); + hints.ai_family = AF_INET; + ret = getaddrinfo(asc, NULL, &hints, &res); + if (ret) + return 0; + + if (res) { + inet4 = (struct sockaddr_in *)res->ai_addr; + addr = inet4->sin_addr.s_addr; + } + + freeaddrinfo(res); + return addr; +} + +static void request_arp(uint32_t ipv4_addr) +{ + struct sockaddr_in inet4; + int sock; + char t = 0; + + 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, 1, 0, (const struct sockaddr *)&inet4, + sizeof(inet4)); + close(sock); +} + +static struct ether_addr *resolve_mac_from_arp(uint32_t ipv4_addr) +{ + struct ether_addr mac_empty; + struct ether_addr *mac_result = NULL, *mac_tmp; + struct sockaddr_in inet4; + 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; + break; + } + } + + free(line); + fclose(f); + return mac_result; +} + +static struct ether_addr *resolve_mac_from_ipv4(const char *asc) +{ + uint32_t ipv4_addr; + 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); + if (!mac_result) { + request_arp(ipv4_addr); + usleep(200000); + } + } + + return mac_result; +} + +struct ether_addr *resolve_mac(const char *asc) +{ + struct ether_addr *mac_result = NULL; + + mac_result = ether_aton(asc); + if (mac_result) + goto out; + + mac_result = resolve_mac_from_ipv4(asc); + +out: + return mac_result; +} diff --git a/functions.h b/functions.h index a59bb24..0ec1d1a 100644 --- a/functions.h +++ b/functions.h @@ -38,6 +38,7 @@ int read_file(char *dir, char *path, int read_opt, float orig_timeout, float watch_interval); int write_file(char *dir, char *fname, char *arg1, char *arg2); struct ether_addr *translate_mac(char *mesh_iface, struct ether_addr *mac); +struct ether_addr *resolve_mac(const char *asc);
extern char *line_ptr;
diff --git a/man/batctl.8 b/man/batctl.8 index a9f032d..234171f 100644 --- a/man/batctl.8 +++ b/man/batctl.8 @@ -204,19 +204,25 @@ tt - translation table counters All counters without a prefix concern payload (pure user data) traffic. .RE .br -.IP "\fBping\fP|\fBp\fP [\fB-c count\fP][\fB-i interval\fP][\fB-t time\fP][\fB-R\fP][\fB-T\fP] \fBMAC_address\fP|\fBbat-host_name\fP" +.IP "\fBping\fP|\fBp\fP [\fB-c count\fP][\fB-i interval\fP][\fB-t time\fP][\fB-R\fP][\fB-T\fP] \fBMAC_address\fP|\fBbat-host_name\fP|\fBhost_name\fP|\fBIPv4_address\fP" Layer 2 ping of a MAC address or bat-host name. batctl will try to find the bat-host name if the given parameter was -not a MAC address. The "-c" option tells batctl how man pings should be sent before the program exits. Without the "-c" +not a MAC address. It can also try to guess the MAC address using an IPv4 address or a hostname when +the IPv4 address was configured on top of the batman-adv interface of the destination device and both source and +destination devices are in the same IPv4 subnet. +The "-c" option tells batctl how man pings should be sent before the program exits. Without the "-c" option batctl will continue pinging without end. Use CTRL + C to stop it. With "-i" and "-t" you can set the default interval between pings and the timeout time for replies, both in seconds. When run with "-R", the route taken by the ping messages will be recorded. With "-T" you can disable the automatic translation of a client MAC address to the originator address which is responsible for this client. .br -.IP "\fBtraceroute\fP|\fBtr\fP [\fB-n\fP][\fB-T\fP] \fBMAC_address\fP|\fBbat-host_name\fP" +.IP "\fBtraceroute\fP|\fBtr\fP [\fB-n\fP][\fB-T\fP] \fBMAC_address\fP|\fBbat-host_name\fP|\fBhost_name\fP|\fBIPv4_address\fP" Layer 2 traceroute to a MAC address or bat-host name. batctl will try to find the bat-host name if the given parameter -was not a MAC address. batctl will send 3 packets to each host and display the response time. If "-n" is given batctl will -not replace the MAC addresses with bat-host names in the output. With "-T" you can disable the automatic translation of a -client MAC address to the originator address which is responsible for this client. +was not a MAC address. It can also try to guess the MAC address using an IPv4 address or a hostname when +the IPv4 address was configured on top of the batman-adv interface of the destination device and both source and +destination devices are in the same IPv4 subnet. +batctl will send 3 packets to each host and display the response time. If "-n" is given batctl will +not replace the MAC addresses with bat-host names in the output. With "-T" you can disable the automatic translation +of a client MAC address to the originator address which is responsible for this client. .br .IP "\fBtcpdump\fP|\fBtd\fP [\fB-c\fP][\fB-n\fP][\fB-p filter\fP][\fB-x filter\fP] \fBinterface ...\fP" batctl will display all packets that are seen on the given interface(s). A variety of options to filter the output diff --git a/ping.c b/ping.c index 02132f4..51d18e8 100644 --- a/ping.c +++ b/ping.c @@ -44,7 +44,7 @@ char is_aborted = 0;
void ping_usage(void) { - printf("Usage: batctl [options] ping [parameters] mac|bat-host \n"); + printf("Usage: batctl [options] ping [parameters] mac|bat-host|host_name|IPv4_address \n"); printf("parameters:\n"); printf(" \t -c ping packet count \n"); printf(" \t -h print this help\n"); @@ -137,10 +137,10 @@ int ping(char *mesh_iface, int argc, char **argv) dst_mac = &bat_host->mac_addr;
if (!dst_mac) { - dst_mac = ether_aton(dst_string); + dst_mac = resolve_mac(dst_string);
if (!dst_mac) { - printf("Error - the ping destination is not a mac address or bat-host name: %s\n", dst_string); + printf("Error - mac address of the ping destination could not be resolved and is not a bat-host name: %s\n", dst_string); goto out; } } diff --git a/traceroute.c b/traceroute.c index 4e42419..ac2f1fa 100644 --- a/traceroute.c +++ b/traceroute.c @@ -43,7 +43,7 @@
void traceroute_usage(void) { - printf("Usage: batctl [options] traceroute [parameters] mac|bat-host \n"); + printf("Usage: batctl [options] traceroute [parameters] mac|bat-host|host_name|IPv4_address \n"); printf("parameters:\n"); printf(" \t -h print this help\n"); printf(" \t -n don't convert addresses to bat-host names\n"); @@ -99,10 +99,10 @@ int traceroute(char *mesh_iface, int argc, char **argv) dst_mac = &bat_host->mac_addr;
if (!dst_mac) { - dst_mac = ether_aton(dst_string); + dst_mac = resolve_mac(dst_string);
if (!dst_mac) { - printf("Error - the traceroute destination is not a mac address or bat-host name: %s\n", dst_string); + printf("Error - mac address of the ping destination could not be resolved and is not a bat-host name: %s\n", dst_string); goto out; } }