Comment cleanup

5 files changed, 68 insertions, 29 deletions

diff --git a/devices.c b/devices.c
index 9293783..b7c1254 100644
--- a/devices.c
+++ b/devices.c
@@ -1,3 +1,21 @@
+/*
+    Mac-Telnet - Connect to RouterOS clients via MAC address
+    Copyright (C) 2010, Håkon Nessjøen <haakon.nessjoen@gmail.com>
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License along
+    with this program; if not, write to the Free Software Foundation, Inc.,
+    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
 #include <stdlib.h>
 #include <string.h>
 #include <malloc.h>
@@ -7,6 +25,8 @@
 #include <sys/ioctl.h>
 #include <net/if.h>
 
+/* Functions using NETDEVICE api */
+
 int getDeviceIndex(int sockfd, unsigned char *deviceName) {
 	struct ifreq ifr;
 
@@ -15,6 +35,7 @@ int getDeviceIndex(int sockfd, unsigned char *deviceName) {
 		return -1;
 	}
 
+	/* Return interface index */
 	return ifr.ifr_ifindex;
 }
 
@@ -26,8 +47,8 @@ int getDeviceMAC(const int sockfd, const unsigned char *deviceName, unsigned cha
 		return -1;
 	}
 
+	/* Fetch mac address */
 	memcpy(mac, ifr.ifr_hwaddr.sa_data, ETH_ALEN);
-
 	return 1;
 }
 
@@ -36,26 +57,35 @@ int getDeviceIp(const int sockfd, const unsigned char *deviceName, struct sockad
 	struct ifreq *ifr;
 	int i,numDevices;
 
+	/*
+	 * Do a initial query without allocating ifreq structs
+	 * to count the number of ifreq structs to allocate memory for
+	*/
 	memset(&ifc, 0, sizeof(ifc));
 	if (ioctl(sockfd, SIOCGIFCONF, &ifc) != 0) {
 		return -1;
 	}
 
+	/*
+	 * Allocate memory for interfaces, multiply by two in case
+	 * the number of interfaces has increased since last ioctl
+	*/
 	if ((ifr = malloc(ifc.ifc_len * 2)) == NULL) {
 		perror("malloc");
 		exit(1);
 	}
 
 	ifc.ifc_req = ifr;
-
 	if (ioctl(sockfd, SIOCGIFCONF, &ifc) != 0) {
 		free(ifr);
 		return -1;
 	}
 
+	/* Iterate through all devices, searching for interface */
 	numDevices = ifc.ifc_len / sizeof(struct ifreq);
 	for (i = 0; i < numDevices; ++i) {
 		if (strcmp(ifr[i].ifr_name, deviceName) == 0) {
+			/* Fetch IP for found interface */
 			memcpy(ip, &(ifr[i].ifr_addr), sizeof(ip));
 			free(ifr);
 			return 1;
diff --git a/mactelnet.c b/mactelnet.c
index 8cfab77..fd814a6 100644
--- a/mactelnet.c
+++ b/mactelnet.c
@@ -24,16 +24,16 @@
 
 int initPacket(unsigned char *data, unsigned char ptype, unsigned char *srcmac, unsigned char *dstmac, unsigned short sessionkey, unsigned short counter) {
 
-	// PACKET VERSION
+	/* PACKET VERSION */
 	data[0] = 1;
 
-	// PACKET TYPE
+	/* PACKET TYPE */
 	data[1] = ptype;
 
-	// src ethernet address
+	/* src ethernet address */
 	memcpy(data + 2, srcmac, ETH_ALEN);
 
-	// dst ethernet address
+	/* dst ethernet address */
 	memcpy(data + 8, dstmac, ETH_ALEN);
 
 	data[14] = sessionkey >> 8;
@@ -56,15 +56,16 @@ int addControlPacket(unsigned char *data, unsigned char cptype, void *cpdata, in
 	data[2] = 0x12;
 	data[3] = 0xff;
 
-	// Control packet type
+	/* Control packet type */
 	data[4] = cptype;
 
-	// Data length
+	/* Data length */
 	data[5] = (data_len >> 24) & 0xff;
 	data[6] = (data_len >> 16) & 0xff;
 	data[7] = (data_len >> 8) & 0xff;
 	data[8] = data_len & 0xff;
 
+	/* Insert data */
 	if (data_len) {
 		memcpy(data+9, cpdata, data_len);
 	}
diff --git a/mactelnet.h b/mactelnet.h
index c9c5c02..d2af675 100644
--- a/mactelnet.h
+++ b/mactelnet.h
@@ -19,13 +19,13 @@
 #ifndef _MACTELNET_H
 #define _MACTELNET_H 1
 
-// Packet type
+/* Packet type */
 #define MT_PTYPE_SESSIONSTART 0
 #define MT_PTYPE_DATA 1
 #define MT_PTYPE_ACK 2
 #define MT_PTYPE_END 255
 
-// Control packet type
+/* Control packet type */
 #define MT_CPTYPE_BEGINAUTH 0
 #define MT_CPTYPE_ENCRYPTIONKEY 1
 #define MT_CPTYPE_PASSWORD 2
@@ -35,7 +35,7 @@
 #define MT_CPTYPE_TERM_HEIGHT 6
 #define MT_CPTYPE_PACKET_ERROR 7
 #define MT_CPTYPE_END_AUTH 9
-// Internal CPTYPE, not part of protocol
+/* Internal CPTYPE, not part of protocol */
 #define MT_CPTYPE_PLAINDATA -1
 
 struct mt_mactelnet_hdr {
diff --git a/main.c b/main.c
index df91f94..d332aca 100644
--- a/main.c
+++ b/main.c
@@ -130,7 +130,7 @@ void handlePacket(unsigned char *data, int data_len) {
 		}
 	}
 	else if (pkthdr.ptype == MT_PTYPE_ACK) {
-		// TODO: If we were resubmitting lost messages, stop resubmitting here if received counter is correct.
+		/* TODO: If we were resubmitting lost messages, stop resubmitting here if received counter is correct. */
 	}
 	else if (pkthdr.ptype == MT_PTYPE_END) {
 		char odata[200];
@@ -144,6 +144,9 @@ void handlePacket(unsigned char *data, int data_len) {
 	}
 }
 
+/*
+ * TODO: Rewrite main() when all sub-functionality is tested
+ */
 int main (int argc, char **argv) {
 	int insockfd;
 	int result;
@@ -163,10 +166,10 @@ int main (int argc, char **argv) {
 
 	srand(time(NULL));
 
-	// Transmit raw packets with this socket
+	/* Transmit raw packets with this socket */
 	sockfd = socket(AF_PACKET, SOCK_RAW, htons(ETH_P_ALL));
 
-	// Receive regular udp packets with this socket
+	/* Receive regular udp packets with this socket */
 	insockfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
 
 	deviceIndex = getDeviceIndex(sockfd, argv[1]);
@@ -175,37 +178,40 @@ int main (int argc, char **argv) {
 		return 1;
 	}
 
-	// Even though we talk to the server without IP address, it makes it much
-	// easier to read packets when we use our real ip as the sender ip.
-	// This way we can listen to normal UDP traffic on port 20561
+	/*
+	 * Even though we talk to the server without IP address, it makes it much
+	 * easier to read packets when we use our real ip as the sender ip.
+	 * This way we can listen to normal UDP traffic on port 20561
+	*/
 	result = getDeviceIp(sockfd, argv[1], &si_me);
 	if (result < 0) {
 		fprintf(stderr, "Cannot determine IP of device %s\n", argv[1]);
 		return 1;
 	}
 
+	/* Determine source mac address */
 	result = getDeviceMAC(sockfd, argv[1], srcmac);
 	if (result < 0) {
 		fprintf(stderr, "Cannot determine MAC address of device %s\n", argv[1]);
 		return 1;
 	}
 
-	// Set up global info about the connection
+	/* Set up global info about the connection */
 	inet_pton(AF_INET, (char *)"255.255.255.255", &destip);
 	memcpy(&sourceip, &(si_me.sin_addr), 4);
 
-	// Initialize receiving socket on the device chosen
+	/* Initialize receiving socket on the device chosen */
 	memset((char *) &si_me, 0, sizeof(si_me));
 	si_me.sin_family = AF_INET;
 	si_me.sin_port = htons(20561);
 
-	// Bind to udp port
+	/* Bind to udp port */
 	if (bind(insockfd, (struct sockaddr *)&si_me, sizeof(si_me))==-1) {
 		fprintf(stderr, "Error binding to %s:20561\n", inet_ntoa(si_me.sin_addr));
 		return 1;
 	}
 
-	// Sessioon key
+	/* Sessioon key */
 	sessionkey = rand() % 65535;
 
 	printf("Connecting to %s...\n", ether_ntoa((struct ether_addr *)dstmac));
@@ -220,8 +226,10 @@ int main (int argc, char **argv) {
 	result = recvfrom(insockfd, buff, 1400, 0, 0, 0);
 	handlePacket(buff, result);
 
-	// TODO: Should resubmit whenever a PTYPE_DATA packet is sent, and an ACK packet with correct datacounter is received
-	// or time out the connection, in all other cases.
+	/*
+	 * TODO: Should resubmit whenever a PTYPE_DATA packet is sent, and an ACK packet with correct datacounter is received
+	 * or time out the connection, in all other cases.
+	*/
 	plen = initPacket(data, MT_PTYPE_DATA, srcmac, dstmac, sessionkey, 0);
 	plen += addControlPacket(data + plen, MT_CPTYPE_BEGINAUTH, NULL, 0);
 	outcounter += 9;
diff --git a/udp.c b/udp.c
index 0cfce5b..10c8f7b 100644
--- a/udp.c
+++ b/udp.c
@@ -49,12 +49,12 @@ int sendCustomUDP(const int socket, const int ifindex, const unsigned char *sour
 		exit(1);
 	}
 
-	// Ethernet header
+	/* Ethernet header */
 	memcpy(eh->h_source, sourcemac, ETH_ALEN);
 	memcpy(eh->h_dest, destmac, ETH_ALEN);
 	eh->h_proto = 8;
 
-	// SendTo struct
+	/* SendTo struct */
 	socket_address.sll_family   = PF_PACKET;	
 	socket_address.sll_protocol = htons(ETH_P_IP);	
 	socket_address.sll_ifindex  = ifindex;
@@ -66,7 +66,7 @@ int sendCustomUDP(const int socket, const int ifindex, const unsigned char *sour
 	socket_address.sll_addr[6]  = 0x00;/*not used*/
 	socket_address.sll_addr[7]  = 0x00;/*not used*/
 
-	// IP Header
+	/* IP Header */
 	ip->version = 4;
 	ip->ihl = 5;
 	ip->tos = 0x10;
@@ -74,13 +74,13 @@ int sendCustomUDP(const int socket, const int ifindex, const unsigned char *sour
 	ip->id = htons(id++);
 	ip->frag_off = 0x0040;
 	ip->ttl = 64;
-	ip->protocol = 17; // UDP
+	ip->protocol = 17; /* UDP */
 	ip->check = 0x0000;
 	ip->saddr = sourceip->s_addr;
 	ip->daddr = destip->s_addr;
 	ip->check = in_cksum((unsigned short *)ip, sizeof(struct iphdr));
 
-	// UDP Header
+	/* UDP Header */
 	udp->source = htons(20561);
 	udp->dest = htons(20561);
 	udp->check = 0;
@@ -88,7 +88,7 @@ int sendCustomUDP(const int socket, const int ifindex, const unsigned char *sour
 
 	memcpy(rest, data, datalen);
 
-	/*send the packet*/
+	/* Send the packet */
 	send_result = sendto(socket, buffer, datalen+8+14+20, 0, (struct sockaddr*)&socket_address, sizeof(socket_address));
 	free(buffer);