preliminary ipv6 support

only basic testing was done (with 2 socks5 proxies listening on ::1)
but seems to work as intended.

ipv6 support for the hostsreader (/etc/hosts) is not implemented so far.

Author: rofl0r

src/allocator_thread.c

@@ -38,16 +38,16 @@ pthread_mutex_t internal_ips_lock;
 internal_ip_lookup_table *internal_ips = NULL;
 internal_ip_lookup_table internal_ips_buf;
 
-uint32_t index_from_internal_ip(ip_type internalip) {
+uint32_t index_from_internal_ip(ip_type4 internalip) {
 	PFUNC();
-	ip_type tmp = internalip;
+	ip_type4 tmp = internalip;
 	uint32_t ret;
 	ret = tmp.octet[3] + (tmp.octet[2] << 8) + (tmp.octet[1] << 16);
 	ret -= 1;
 	return ret;
 }
 
-char *string_from_internal_ip(ip_type internalip) {
+char *string_from_internal_ip(ip_type4 internalip) {
 	PFUNC();
 	char *res = NULL;
 	uint32_t index = index_from_internal_ip(internalip);
@@ -57,22 +57,22 @@ char *string_from_internal_ip(ip_type internalip) {
 }
 
 extern unsigned int remote_dns_subnet;
-ip_type make_internal_ip(uint32_t index) {
-	ip_type ret;
+ip_type4 make_internal_ip(uint32_t index) {
+	ip_type4 ret;
 	index++; // so we can start at .0.0.1
 	if(index > 0xFFFFFF)
-		return ip_type_invalid;
+		return ip_type_invalid.addr.v4;
 	ret.octet[0] = remote_dns_subnet & 0xFF;
 	ret.octet[1] = (index & 0xFF0000) >> 16;
 	ret.octet[2] = (index & 0xFF00) >> 8;
 	ret.octet[3] = index & 0xFF;
 	return ret;
 }
 
-static ip_type ip_from_internal_list(char* name, size_t len) {
+static ip_type4 ip_from_internal_list(char* name, size_t len) {
 	uint32_t hash = dalias_hash((char *) name);
 	size_t i;
-	ip_type res;
+	ip_type4 res;
 	void* new_mem;
 	// see if we already have this dns entry saved.
 	if(internal_ips->counter) {
@@ -99,7 +99,7 @@ static ip_type ip_from_internal_list(char* name, size_t len) {
 	}
 
 	res = make_internal_ip(internal_ips->counter);
-	if(res.as_int == ip_type_invalid.as_int)
+	if(res.as_int == ip_type_invalid.addr.v4.as_int)
 		goto err_plus_unlock;
 
 	string_hash_tuple tmp = { 0 };
@@ -128,7 +128,7 @@ static ip_type ip_from_internal_list(char* name, size_t len) {
 	err_plus_unlock:
 
 	PDEBUG("return err\n");
-	return ip_type_invalid;
+	return ip_type_invalid.addr.v4;
 }
 
 /* stuff for communication with the allocator thread */
@@ -205,15 +205,15 @@ static void* threadfunc(void* x) {
 	struct at_msghdr msg;
 	union { 
 		char host[MSG_LEN_MAX];
-		ip_type ip;
+		ip_type4 ip;
 	} readbuf;
 	while((ret = getmessage(ATD_SERVER, &msg, &readbuf))) {
 		switch(msg.msgtype) {
 			case ATM_GETIP:
 				/* client wants an ip for a DNS name. iterate our list and check if we have an existing entry.
 					* if not, create a new one. */
 				readbuf.ip = ip_from_internal_list(readbuf.host, msg.datalen - 1);
-				msg.datalen = sizeof(ip_type);
+				msg.datalen = sizeof(ip_type4);
 				break;
 			case ATM_GETNAME: {
 				char *host = string_from_internal_ip(readbuf.ip);
@@ -237,23 +237,23 @@ static void* threadfunc(void* x) {
 
 /* API to access the internal ip mapping */
 
-ip_type at_get_ip_for_host(char* host, size_t len) {
-	ip_type readbuf;
+ip_type4 at_get_ip_for_host(char* host, size_t len) {
+	ip_type4 readbuf;
 	MUTEX_LOCK(&internal_ips_lock);
 	if(len > MSG_LEN_MAX) goto inv;
 	struct at_msghdr msg = {.msgtype = ATM_GETIP, .datalen = len + 1 };
 	if(sendmessage(ATD_SERVER, &msg, host) &&
 	   getmessage(ATD_CLIENT, &msg, &readbuf));
 	else {
 		inv:
-		readbuf = ip_type_invalid;
+		readbuf = ip_type_invalid.addr.v4;
 	}
 	MUTEX_UNLOCK(&internal_ips_lock);
 	return readbuf;
 }
 
-size_t at_get_host_for_ip(ip_type ip, char* readbuf) {
-	struct at_msghdr msg = {.msgtype = ATM_GETNAME, .datalen = sizeof(ip_type) };
+size_t at_get_host_for_ip(ip_type4 ip, char* readbuf) {
+	struct at_msghdr msg = {.msgtype = ATM_GETNAME, .datalen = sizeof(ip_type4) };
 	size_t res = 0;
 	MUTEX_LOCK(&internal_ips_lock);
 	if(sendmessage(ATD_SERVER, &msg, &ip) && getmessage(ATD_CLIENT, &msg, readbuf)) {

src/allocator_thread.h

@@ -11,8 +11,8 @@ extern int resp_pipefd[2];
 
 void at_init(void);
 void at_close(void);
-size_t at_get_host_for_ip(ip_type ip, char* readbuf);
-ip_type at_get_ip_for_host(char* host, size_t len);
+size_t at_get_host_for_ip(ip_type4 ip, char* readbuf);
+ip_type4 at_get_ip_for_host(char* host, size_t len);
 
 //RcB: DEP "allocator_thread.c"
 #endif

src/core.c

@@ -198,8 +198,8 @@ static int tunnel_to(int sock, ip_type ip, unsigned short port, proxy_type pt, c
 	// the range 224-255.* is reserved, and it won't go outside (unless the app does some other stuff with
 	// the results returned from gethostbyname et al.)
 	// the hardcoded number 224 can now be changed using the config option remote_dns_subnet to i.e. 127
-	if(ip.octet[0] == remote_dns_subnet) {
-		dns_len = at_get_host_for_ip(ip, hostnamebuf);
+	if(!ip.is_v6 && ip.addr.v4.octet[0] == remote_dns_subnet) {
+		dns_len = at_get_host_for_ip(ip.addr.v4, hostnamebuf);
 		if(!dns_len) goto err;
 		else dns_name = hostnamebuf;
 	}
@@ -216,12 +216,16 @@ static int tunnel_to(int sock, ip_type ip, unsigned short port, proxy_type pt, c
 
 	int len;
 	unsigned char buff[BUFF_SIZE];
-	char ip_buf[16];
+	char ip_buf[INET6_ADDRSTRLEN];
+	int v6 = ip.is_v6;
 
 	switch (pt) {
 		case HTTP_TYPE:{
 			if(!dns_len) {
-				pc_stringfromipv4(&ip.octet[0], ip_buf);
+				if(!inet_ntop(v6?AF_INET6:AF_INET,ip.addr.v6,ip_buf,sizeof ip_buf)) {
+					proxychains_write_log(LOG_PREFIX "error: ip address conversion failed\n");
+					goto err;
+				}
 				dns_name = ip_buf;
 			}
 			#define HTTP_AUTH_MAX ((0xFF * 2) + 1 + 1) /* 2 * 0xff: username and pass, plus 1 for ':' and 1 for zero terminator. */
@@ -264,16 +268,20 @@ static int tunnel_to(int sock, ip_type ip, unsigned short port, proxy_type pt, c
 		}
 		break;
 		case SOCKS4_TYPE:{
+			if(v6) {
+				proxychains_write_log(LOG_PREFIX "error: SOCKS4 doesnt support ipv6 addresses\n");
+				goto err;
+			}
 			buff[0] = 4;	// socks version
 			buff[1] = 1;	// connect command
 			memcpy(&buff[2], &port, 2);	// dest port
 			if(dns_len) {
-				ip.octet[0] = 0;
-				ip.octet[1] = 0;
-				ip.octet[2] = 0;
-				ip.octet[3] = 1;
+				ip.addr.v4.octet[0] = 0;
+				ip.addr.v4.octet[1] = 0;
+				ip.addr.v4.octet[2] = 0;
+				ip.addr.v4.octet[3] = 1;
 			}
-			memcpy(&buff[4], &ip, 4);	// dest host
+			memcpy(&buff[4], &ip.addr.v4, 4);	// dest host
 			len = ulen + 1;	// username
 			if(len > 1)
 				memcpy(&buff[8], user, len);
@@ -353,9 +361,9 @@ static int tunnel_to(int sock, ip_type ip, unsigned short port, proxy_type pt, c
 			buff[buff_iter++] = 0;	// reserved
 
 			if(!dns_len) {
-				buff[buff_iter++] = 1;	// ip v4
-				memcpy(buff + buff_iter, &ip, 4);	// dest host
-				buff_iter += 4;
+				buff[buff_iter++] = v6 ? 4 : 1;	// ip v4/v6
+				memcpy(buff + buff_iter, ip.addr.v6, v6?16:4);	// dest host
+				buff_iter += v6?16:4;
 			} else {
 				buff[buff_iter++] = 3;	//dns
 				buff[buff_iter++] = dns_len & 0xFF;
@@ -411,21 +419,30 @@ static int tunnel_to(int sock, ip_type ip, unsigned short port, proxy_type pt, c
 #define RRT "Round Robin chain"
 
 static int start_chain(int *fd, proxy_data * pd, char *begin_mark) {
-	*fd = socket(PF_INET, SOCK_STREAM, 0);
+	int v6 = pd->ip.is_v6;
+
+	*fd = socket(v6?PF_INET6:PF_INET, SOCK_STREAM, 0);
 	if(*fd == -1)
 		goto error;
 
-	char ip_buf[16];
-	pc_stringfromipv4(&pd->ip.octet[0], ip_buf);
+	char ip_buf[INET6_ADDRSTRLEN];
+	if(!inet_ntop(v6?AF_INET6:AF_INET,pd->ip.addr.v6,ip_buf,sizeof ip_buf))
+		goto error;
+
 	proxychains_write_log(LOG_PREFIX "%s " TP " %s:%d ",
 			      begin_mark, ip_buf, htons(pd->port));
 	pd->ps = PLAY_STATE;
 	struct sockaddr_in addr = {
 		.sin_family = AF_INET,
 		.sin_port = pd->port,
-		.sin_addr.s_addr = (in_addr_t) pd->ip.as_int
+		.sin_addr.s_addr = (in_addr_t) pd->ip.addr.v4.as_int
+	};
+	struct sockaddr_in6 addr6 = {
+		.sin6_family = AF_INET6,
+		.sin6_port = pd->port,
 	};
-	if(timed_connect(*fd, (struct sockaddr *) &addr, sizeof(addr))) {
+	if(v6) memcpy(&addr6.sin6_addr.s6_addr, pd->ip.addr.v6, 16);
+	if(timed_connect(*fd, (struct sockaddr *) (v6?(void*)&addr6:(void*)&addr), v6?sizeof(addr6):sizeof(addr))) {
 		pd->ps = DOWN_STATE;
 		goto error1;
 	}
@@ -496,16 +513,22 @@ static int chain_step(int ns, proxy_data * pfrom, proxy_data * pto) {
 	int retcode = -1;
 	char *hostname;
 	char hostname_buf[MSG_LEN_MAX];
-	char ip_buf[16];
+	char ip_buf[INET6_ADDRSTRLEN];
+	int v6 = pto->ip.is_v6;
 
 	PFUNC();
 
-	if(pto->ip.octet[0] == remote_dns_subnet) {
-		if(!at_get_host_for_ip(pto->ip, hostname_buf)) goto usenumericip;
+	if(!v6 && pto->ip.addr.v4.octet[0] == remote_dns_subnet) {
+		if(!at_get_host_for_ip(pto->ip.addr.v4, hostname_buf)) goto usenumericip;
 		else hostname = hostname_buf;
 	} else {
 	usenumericip:
-		pc_stringfromipv4(&pto->ip.octet[0], ip_buf);
+		if(!inet_ntop(v6?AF_INET6:AF_INET,pto->ip.addr.v6,ip_buf,sizeof ip_buf)) {
+			pto->ps = DOWN_STATE;
+			proxychains_write_log("<--ip conversion error!\n");
+			close(ns);
+			return SOCKET_ERROR;
+		}
 		hostname = ip_buf;
 	}
 
@@ -707,7 +730,7 @@ static void gethostbyname_data_setstring(struct gethostbyname_data* data, char*
 	data->hostent_space.h_name = data->addr_name;
 }
 
-extern ip_type hostsreader_get_numeric_ip_for_name(const char* name);
+extern ip_type4 hostsreader_get_numeric_ip_for_name(const char* name);
 struct hostent *proxy_gethostbyname(const char *name, struct gethostbyname_data* data) {
 	PFUNC();
 	char buff[256];
@@ -728,19 +751,19 @@ struct hostent *proxy_gethostbyname(const char *name, struct gethostbyname_data*
 	if(!strcmp(buff, name)) {
 		data->resolved_addr = inet_addr(buff);
 		if(data->resolved_addr == (in_addr_t) (-1))
-			data->resolved_addr = (in_addr_t) (ip_type_localhost.as_int);
+			data->resolved_addr = (in_addr_t) (ip_type_localhost.addr.v4.as_int);
 		goto retname;
 	}
 
 	// this iterates over the "known hosts" db, usually /etc/hosts
-	ip_type hdb_res = hostsreader_get_numeric_ip_for_name(name);
-	if(hdb_res.as_int != ip_type_invalid.as_int) {
+	ip_type4 hdb_res = hostsreader_get_numeric_ip_for_name(name);
+	if(hdb_res.as_int != ip_type_invalid.addr.v4.as_int) {
 		data->resolved_addr = hdb_res.as_int;
 		goto retname;
 	}
 
 	data->resolved_addr = at_get_ip_for_host((char*) name, strlen(name)).as_int;
-	if(data->resolved_addr == (in_addr_t) ip_type_invalid.as_int) return NULL;
+	if(data->resolved_addr == (in_addr_t) ip_type_invalid.addr.v4.as_int) return NULL;
 
 	retname:
 

src/hostsreader.c

@@ -73,16 +73,16 @@ char* hostsreader_get_ip_for_name(const char* name, char* buf, size_t bufsize) {
 #include <netinet/in.h>
 #include <sys/socket.h>
 #include <arpa/inet.h>
-ip_type hostsreader_get_numeric_ip_for_name(const char* name) {
+ip_type4 hostsreader_get_numeric_ip_for_name(const char* name) {
 	char *hres;
 	char buf[320];
 	if((hres = hostsreader_get_ip_for_name(name, buf, sizeof buf))) {
 		struct in_addr c;
 		inet_aton(hres, &c);
-		ip_type res;
+		ip_type4 res;
 		memcpy(res.octet, &c.s_addr, 4);
 		return res;
-	} else return ip_type_invalid;
+	} else return ip_type_invalid.addr.v4;
 }
 
 #ifdef HOSTSREADER_TEST

src/ip_type.c

@@ -1,5 +1,5 @@
 #include "ip_type.h"
 
-const ip_type ip_type_invalid = { .as_int = -1 };
-const ip_type ip_type_localhost = { {127, 0, 0, 1} };
+const ip_type ip_type_invalid = { .addr.v4.as_int = -1 };
+const ip_type ip_type_localhost = { .addr.v4 = {127, 0, 0, 1} };
 

src/ip_type.h

@@ -6,6 +6,14 @@
 typedef union {
 	unsigned char octet[4];
 	uint32_t as_int;
+} ip_type4;
+
+typedef struct {
+	union {
+		ip_type4 v4;
+		unsigned char v6[16];
+	} addr;
+	char is_v6;
 } ip_type;
 
 extern const ip_type ip_type_invalid;