Work

- Typo fix

TAP.c

@@ -1,18 +1,12 @@
 #include "TAP.h"
 
-// Needed for in6_ifreq
-#include <arpa/inet.h>
-#include <linux/ipv6.h>
-#include <netinet/in.h>
-#include <sys/ioctl.h>
-#include <sys/socket.h>
-
 char tap_name[IFNAMSIZ];
 
 extern bool verbose;
 extern bool noipv6;
 extern bool set_ipv4;
 extern bool set_ipv6;
+extern bool set_linklocal;
 extern bool set_netmask;
 extern bool noup;
 extern int mtu;
@@ -20,66 +14,10 @@ extern int device_type;
 extern char if_name[IFNAMSIZ];
 extern char* ipv4_addr;
 extern char* ipv6_addr;
+extern long ipv6_prefixLen;
 extern char* netmask;
 extern void cleanup();
 
-#include<stdlib.h>
-
-void localRand(struct in6_addr* ll_a)
-{
-    for(int i = 2; i < 16; i++)
-    {
-        ll_a->s6_addr[i] = rand();
-    }
-}
-
-#include<time.h>
-
-// TODO: Allow optional-arg for case where we must also generate the hwaddr
-// (this would be the case whereby we are running without `--ethernet`)
-struct in6_addr generateLinkLocal(char* interfaceName)
-{
-    time_t t = time(NULL);
-    srand(t);
-
-    struct in6_addr ll_a;
-    memset(&ll_a, 0, sizeof(struct in6_addr));
-    ll_a.s6_addr[0] = 0xfe;
-    ll_a.s6_addr[1] = 0x80;
-
-    // TODO: Set the rest here
-
-    // TODO: Loop till we generate an address NOT in use
-    // (TODO, should not matter, link-local is interface scoped)
-    // TODO: Should tie it to mac address because of uniqueness
-    // on the lan it shall attach to (over lora)
-    localRand(&ll_a);
-
-    
-
-
-
-    int dummySock = socket(AF_PACKET, SOCK_PACKET, 0);
-    if(dummySock < 0)
-    {
-        printf("Failed to open configuration socket in order to generate link-local address\n");
-        close(dummySock);
-        exit(1);
-    }
-
-    struct ifreq reqParams;
-    memset(&reqParams, 0, sizeof(reqParams));
-    strcpy(reqParams.ifr_name, interfaceName);
-
-    if(ioctl(dummySock, SIOCGIFHWADDR, &reqParams) < 0)
-    {
-        printf("Failed to fetch hardware address Failed to open configuration socket in order to generate link-local address\n");
-        close(dummySock);
-        exit(1);
-    }
-
-    return ll_a;
-}
 
 void trySixSet
 (
@@ -99,35 +37,40 @@ void trySixSet
         interfaceIndex
     );
 
-	int dummySock = socket(AF_INET6, SOCK_DGRAM, 0);
+	int inet6 = socket(AF_INET6, SOCK_DGRAM, 0);
+    if(inet6 < 0)
+    {
+        printf("Error opening control socket for adding IPv6 address to interface\n");
+        cleanup();
+        exit(1);
+    }
 
-
-
-	
 	struct in6_ifreq paramReq;
 	memset(&paramReq, 0, sizeof(struct in6_ifreq));
 	paramReq.ifr6_ifindex = interfaceIndex;
- 	printf("paramReq.ifr6_ifindex: %d\n", paramReq.ifr6_ifindex);
  	paramReq.ifr6_prefixlen = prefixLen;
  	paramReq.ifr6_addr = address;
 
 	
-
-	if(ioctl(dummySock, SIOCSIFADDR, &paramReq) < 0)
+    // Try add the address
+	if(ioctl(inet6, SIOCSIFADDR, &paramReq) < 0)
 	{
- 		// perror("Fokop");
- 		printf("Fokop\n");
+ 		printf
+        (
+            "There was an errror assigning address '%s/%d' to if_index %d\n",
+            ip_str,
+            prefixLen,
+            interfaceIndex
+        );
  		cleanup();
- 		close(dummySock);
+ 		close(inet6);
  		exit(1);
  	}
 
-    printf("Sucessfully applied IPv6 configuration");
-	close(dummySock);
+    printf("Address '%s/%d' added\n", ip_str, prefixLen);
+	close(inet6);
 }
 
-#include<string.h>
-
 int open_tap(void) {
     struct ifreq ifr;
     int fd = open("/dev/net/tun", O_RDWR);
@@ -159,17 +102,9 @@ int open_tap(void) {
             strcpy(if_name, ifr.ifr_name);
 
             
-            int inet = socket(set_ipv4 ? AF_INET : AF_INET6, SOCK_DGRAM, 0);
-            printf("inet fd: %d\n", inet);
-            printf("tun/tap handle fd: %d\n", fd);
-						printf("set_ipv4: %d\n", set_ipv4);
-						printf("set_ipv6: %d\n", set_ipv6);
-            
-            // inet=fd;
+            int inet = socket(AF_INET, SOCK_DGRAM, 0);
             if (inet == -1) {
-            	  char err[100];
-            		sprintf(err, "Could not open %s socket", set_ipv4 ? "AF_INET" : "AF_INET6");
-                perror(err);
+                perror("Could not open control socket");
                 cleanup();
                 exit(1);
             } else {
@@ -306,64 +241,52 @@ int open_tap(void) {
                                     }
                                 }
 
-                                if(set_ipv6) {
-                                	printf("TODO: Implement set ipv6\n");
-
+                                if(set_ipv6 || set_linklocal)
+                                {
                                     // Firstly, obtain the interface index by `ifr_name`
-                                    int dummySock = socket(AF_INET6, SOCK_DGRAM, 0);
-                                    if(ioctl(dummySock, SIOCGIFINDEX, &ifr) < 0)
+                                    int inet6 = socket(AF_INET6, SOCK_DGRAM, 0);
+                                    if(inet6 < 0)
                                     {
-                                        printf("Could not get interface index for interface '%s'\n", ifr.ifr_name);
-                                        close(dummySock);
-                                        exit(1);
-                                    }					
-
-                                    
-                                    char* ipPart = strtok(ipv6_addr, "/");
-                                    char* prefixPart_s = strtok(NULL, "/");
-                                    printf("ip part: %s\n", ipPart);
-
-                                    if(!prefixPart_s)
-                                    {
-                                        perror("No prefix length was provided"); // TODO: Move logic into arg parsing
-                                        close(dummySock);
+                                        printf("Error opening control socket for adding IPv6 address to interface\n");
+                                        cleanup();
                                         exit(1);
                                     }
-                                    printf("prefix part: %s\n", prefixPart_s);
-
-                                    long prefixLen_l = strtol(prefixPart_s, NULL, 10); // TODO: Add handling here for errors (using errno)
 
+                                    if(ioctl(inet6, SIOCGIFINDEX, &ifr) < 0)
+                                    {
+                                        printf("Could not get interface index for interface '%s'\n", ifr.ifr_name);
+                                        close(inet6);
+                                        cleanup();
+                                        exit(1);
+                                    }
 
+																		// if link-local was NOT requested and interface
+																		// has been up'd -> then kernel would have added
+																		// a link-local already, this removes it
+                                    if(!set_linklocal & !noup)
+                                    {
+                                    		// TODO: Get all addresses that start with fe80
+                                    }
+                                    // Else it could have been no-up; hence you will have to remove
+                                    // the link-local yourself
+                                    // Other else is link-local was requested, then we don't care (whether
+                                    // up'd or not as it will inevitably be added by the kernel)
 
                                     // Convert ASCII IPv6 address to ABI structure
                                     struct in6_addr six_addr_itself;
                                     memset(&six_addr_itself, 0, sizeof(struct in6_addr));
                                     if(inet_pton(AF_INET6, ipv6_addr, &six_addr_itself) < 0)
                                     {
-                                        printf("Error parsing IPv6 address '%s'", ipv6_addr);
-                                        close(dummySock);
+                                        printf("Error parsing IPv6 address '%s'\n", ipv6_addr);
+                                        close(inet6);
+                                        cleanup();
                                         exit(1);
                                     }
 
-                                    // Choose stratergy for generating link-local address
-                                    if(device_type == IF_TAP)                                
-                                    {
-
-                                    }
-                                    else
-                                    {
-
-                                    }
-
-                                    // Add link-local address
-                                    trySixSet(ifr.ifr_ifindex, generateLinkLocal(if_name), 64);
-
                                     // Add user's requested address
-                                    trySixSet(ifr.ifr_ifindex, six_addr_itself, prefixLen_l);
+                                    trySixSet(ifr.ifr_ifindex, six_addr_itself, ipv6_prefixLen);
 
-                                    // FIXME: Allow the ipv6 to be empty and just do link-local
-
-                                    printf("IPv6 settings SHOULD be done now\n");
+                                    close(inet6);
                                 }
                             }
                         }

TAP.h

@@ -9,6 +9,7 @@
 #include <linux/if_tun.h>
 #include <sys/socket.h>
 #include <arpa/inet.h>
+#include <linux/ipv6.h>
 #include "Constants.h"
 
 int open_tap(void);

tncattach.c

@@ -35,12 +35,14 @@ bool noup = false;
 bool daemonize = false;
 bool set_ipv4 = false;
 bool set_ipv6 = false;
+bool set_linklocal = false;
 bool set_netmask = false;
 bool kiss_over_tcp = false;
 char* ipv4_addr;
 char* netmask;
 
 char* ipv6_addr;
+long ipv6_prefixLen;
 
 char* tcp_host;
 int tcp_port;
@@ -273,15 +275,16 @@ static struct argp_option options[] = {
     { "ethernet", 'e', 0, 0, "Create a full ethernet device", 2},
     { "ipv4", 'i', "IP_ADDRESS", 0, "Configure an IPv4 address on interface", 3},
     { "ipv6", '6', "IP6_ADDRESS", 0, "Configure an IPv6 address on interface", 4},
-    { "noipv6", 'n', 0, 0, "Filter IPv6 traffic from reaching TNC", 5},
-    { "noup", 1, 0, 0, "Only create interface, don't bring it up", 6},
-    { "kisstcp", 'T', 0, 0, "Use KISS over TCP instead of serial port", 7},
-    { "tcphost", 'H', "TCP_HOST", 0, "Host to connect to when using KISS over TCP", 8},
-    { "tcpport", 'P', "TCP_PORT", 0, "TCP port when using KISS over TCP", 9},
-    { "interval", 't', "SECONDS", 0, "Maximum interval between station identifications", 10},
-    { "id", 's', "CALLSIGN", 0, "Station identification data", 11},
-    { "daemon", 'd', 0, 0, "Run tncattach as a daemon", 12},
-    { "verbose", 'v', 0, 0, "Enable verbose output", 13},
+    { "ll", 'l', 0, 0, "Add a link-local Ipv6 address", 5},
+    { "noipv6", 'n', 0, 0, "Filter IPv6 traffic from reaching TNC", 6},
+    { "noup", 1, 0, 0, "Only create interface, don't bring it up", 7},
+    { "kisstcp", 'T', 0, 0, "Use KISS over TCP instead of serial port", 8},
+    { "tcphost", 'H', "TCP_HOST", 0, "Host to connect to when using KISS over TCP", 9},
+    { "tcpport", 'P', "TCP_PORT", 0, "TCP port when using KISS over TCP", 10},
+    { "interval", 't', "SECONDS", 0, "Maximum interval between station identifications", 11},
+    { "id", 's', "CALLSIGN", 0, "Station identification data", 12},
+    { "daemon", 'd', 0, 0, "Run tncattach as a daemon", 13},
+    { "verbose", 'v', 0, 0, "Enable verbose output", 14},
     { 0 }
 };
 
@@ -302,6 +305,7 @@ struct arguments {
     bool set_ipv4;
     bool set_netmask;
     bool set_ipv6;
+    bool link_local_v6;
     bool set_netmask_v6;
     bool noipv6;
     bool noup;
@@ -328,6 +332,13 @@ static error_t parse_opt(int key, char *arg, struct argp_state *state) {
                 printf("Error: Invalid MTU specified\r\n\r\n");
                 argp_usage(state);
             }
+
+            if((arguments->set_ipv6 || arguments->link_local_v6) && arguments->mtu < 1280)
+            {
+                printf("IPv6 and/or link-local IPv6 was requested, but the MTU provided is lower than 1280\n");
+                exit(EXIT_FAILURE);
+            }
+
             break;
 
         case 't':
@@ -479,13 +490,46 @@ static error_t parse_opt(int key, char *arg, struct argp_state *state) {
                 perror("Sorry, but you had noipv6 set yet want to use ipv6?\n");
                 exit(EXIT_FAILURE);
             }
-            arguments->ipv6 = arg;
+
+            char* ipPart_s = strtok(arg, "/");
+            char* prefixPart_s = strtok(NULL, "/");
+            printf("ipPart_s: %s\n", ipPart_s);
+
+            if(!prefixPart_s)
+            {
+                printf("No prefix length was provided\n");
+                exit(1);
+            }
+            printf("prefixPart_s: %s\n", prefixPart_s);
+
+            long prefixLen_l = strtol(prefixPart_s, NULL, 10); // TODO: Add handling here for errors (using errno)
+
+
+            arguments->ipv6 = ipPart_s;
+            
             arguments->set_ipv6 = true;
 
-            // Save to the global for other modules to access it
+            // Copy across global IPv6 address
             ipv6_addr = malloc(strlen(arguments->ipv6)+1);
             strcpy(ipv6_addr, arguments->ipv6);
-            printf("v6 now: %s\n", ipv6_addr);
+
+            // Set global IPv6 prefix length
+            ipv6_prefixLen = prefixLen_l;
+
+            printf("MTU was %d, setting to minimum of %d as is required for IPv6\n", arguments->mtu, 1280);
+            arguments->mtu = 1280;
+            break;
+
+        case 'l':
+            if(arguments->noipv6)
+            {
+                perror("Sorry, but you had noipv6 set yet want to use ipv6 link-local?\n");
+                exit(EXIT_FAILURE);
+            }
+            arguments->link_local_v6 = true;
+
+            printf("MTU was %d, setting to minimum of %d as is required for IPv6\n", arguments->mtu, 1280);
+            arguments->mtu = 1280;
             break;
 						
         case 'n':
@@ -586,6 +630,7 @@ int main(int argc, char **argv) {
     arguments.set_ipv4 = false;
     arguments.set_netmask = false;
     arguments.set_ipv6 = false;
+    arguments.link_local_v6 = false;
     arguments.set_netmask_v6 = false;
     arguments.noipv6 = false;
     arguments.daemon = false;
@@ -661,4 +706,4 @@ int main(int argc, char **argv) {
     read_loop();
 
     return 0;
-}
+}