source: protocols/proxy.c @ a03a9f3

/*
 * gaim
 *
 * Copyright (C) 1998-1999, Mark Spencer <markster@marko.net>
 * Copyright (C) 2002-2004, Wilmer van der Gaast, Jelmer Vernooij
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

/* this is a little piece of code to handle proxy connection */
/* it is intended to : 1st handle http proxy, using the CONNECT command
 , 2nd provide an easy way to add socks support */

#define BITLBEE_CORE
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#ifndef _WIN32
#include <sys/socket.h>
#include <netdb.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>
#else
#include "sock.h"
#define ETIMEDOUT WSAETIMEDOUT
#define EINPROGRESS WSAEINPROGRESS
#endif
#include <fcntl.h>
#include <errno.h>
#include "nogaim.h"
#include "proxy.h"

#define GAIM_READ_COND  (G_IO_IN | G_IO_HUP | G_IO_ERR)
#define GAIM_WRITE_COND (G_IO_OUT | G_IO_HUP | G_IO_ERR | G_IO_NVAL)
#define GAIM_ERR_COND   (G_IO_HUP | G_IO_ERR | G_IO_NVAL)

char proxyhost[128] = "";
int proxyport = 0;
int proxytype = PROXY_NONE;
char proxyuser[128] = "";
char proxypass[128] = "";

struct PHB {
        GaimInputFunction func, proxy_func;
        gpointer data, proxy_data;
        char *host;
        int port;
        int fd;
        gint inpa;
};

typedef struct _GaimIOClosure {
        GaimInputFunction function;
        guint result;
        gpointer data;
} GaimIOClosure;



static struct sockaddr_in *gaim_gethostbyname(const char *host, int port)
{
        static struct sockaddr_in sin;

        if (!inet_aton(host, &sin.sin_addr)) {
                struct hostent *hp;
                if (!(hp = gethostbyname(host))) {
                        return NULL;
                }
                memset(&sin, 0, sizeof(struct sockaddr_in));
                memcpy(&sin.sin_addr.s_addr, hp->h_addr, hp->h_length);
                sin.sin_family = hp->h_addrtype;
        } else
                sin.sin_family = AF_INET;
        sin.sin_port = htons(port);

        return &sin;
}

static void gaim_io_destroy(gpointer data)
{
        g_free(data);
}

static gboolean gaim_io_invoke(GIOChannel *source, GIOCondition condition, gpointer data)
{
        GaimIOClosure *closure = data;
        GaimInputCondition gaim_cond = 0;

        if (condition & GAIM_READ_COND)
                gaim_cond |= GAIM_INPUT_READ;
        if (condition & GAIM_WRITE_COND)
                gaim_cond |= GAIM_INPUT_WRITE;

        closure->function(closure->data, g_io_channel_unix_get_fd(source), gaim_cond);

        return TRUE;
}

static void gaim_io_connected(gpointer data, gint source, GaimInputCondition cond)
{
        struct PHB *phb = data;
        unsigned int len;
        int error = ETIMEDOUT;
        len = sizeof(error);
        
#ifndef _WIN32
        if (getsockopt(source, SOL_SOCKET, SO_ERROR, &error, &len) < 0) {
                closesocket(source);
                gaim_input_remove(phb->inpa);
                if( phb->proxy_func )
                        phb->proxy_func(phb->proxy_data, -1, GAIM_INPUT_READ);
                else {
                        phb->func(phb->data, -1, GAIM_INPUT_READ);
                        g_free(phb);
                }
                return;
        }
#endif
        sock_make_blocking(source);
        gaim_input_remove(phb->inpa);
        if( phb->proxy_func )
                phb->proxy_func(phb->proxy_data, source, GAIM_INPUT_READ);
        else {
                phb->func(phb->data, source, GAIM_INPUT_READ);
                g_free(phb);
        }
}

static int proxy_connect_none(const char *host, unsigned short port, struct PHB *phb)
{
        struct sockaddr_in *sin;
        int fd = -1;

        if (!(sin = gaim_gethostbyname(host, port))) {
                g_free(phb);
                return -1;
        }

        if ((fd = socket(sin->sin_family, SOCK_STREAM, 0)) < 0) {
                g_free(phb);
                return -1;
        }

        sock_make_nonblocking(fd);

        if (connect(fd, (struct sockaddr *)sin, sizeof(*sin)) < 0) {
                if (sockerr_again()) {
                        phb->inpa = gaim_input_add(fd, GAIM_INPUT_WRITE, gaim_io_connected, phb);
                        phb->fd = fd;
                } else {
                        closesocket(fd);
                        g_free(phb);
                        return -1;
                }
        }

        return fd;
}


/* Connecting to HTTP proxies */

#define HTTP_GOODSTRING "HTTP/1.0 200 Connection established"
#define HTTP_GOODSTRING2 "HTTP/1.1 200 Connection established"

static void http_canread(gpointer data, gint source, GaimInputCondition cond)
{
        int nlc = 0;
        int pos = 0;
        struct PHB *phb = data;
        char inputline[8192];

        gaim_input_remove(phb->inpa);

        while ((pos < sizeof(inputline)-1) && (nlc != 2) && (read(source, &inputline[pos++], 1) == 1)) {
                if (inputline[pos - 1] == '\n')
                        nlc++;
                else if (inputline[pos - 1] != '\r')
                        nlc = 0;
        }
        inputline[pos] = '\0';

        if ((memcmp(HTTP_GOODSTRING, inputline, strlen(HTTP_GOODSTRING)) == 0) ||
            (memcmp(HTTP_GOODSTRING2, inputline, strlen(HTTP_GOODSTRING2)) == 0)) {
                phb->func(phb->data, source, GAIM_INPUT_READ);
                g_free(phb->host);
                g_free(phb);
                return;
        }

        close(source);
        phb->func(phb->data, -1, GAIM_INPUT_READ);
        g_free(phb->host);
        g_free(phb);
        return;
}

static void http_canwrite(gpointer data, gint source, GaimInputCondition cond)
{
        char cmd[384];
        struct PHB *phb = data;
        unsigned int len;
        int error = ETIMEDOUT;
        if (phb->inpa > 0)
                gaim_input_remove(phb->inpa);
        len = sizeof(error);
        if (getsockopt(source, SOL_SOCKET, SO_ERROR, &error, &len) < 0) {
                close(source);
                phb->func(phb->data, -1, GAIM_INPUT_READ);
                g_free(phb->host);
                g_free(phb);
                return;
        }
        sock_make_blocking(source);

        g_snprintf(cmd, sizeof(cmd), "CONNECT %s:%d HTTP/1.1\r\nHost: %s:%d\r\n", phb->host, phb->port,
                   phb->host, phb->port);
        if (send(source, cmd, strlen(cmd), 0) < 0) {
                close(source);
                phb->func(phb->data, -1, GAIM_INPUT_READ);
                g_free(phb->host);
                g_free(phb);
                return;
        }

        if (proxyuser && *proxyuser) {
                char *t1, *t2;
                t1 = g_strdup_printf("%s:%s", proxyuser, proxypass);
                t2 = tobase64(t1);
                g_free(t1);
                g_snprintf(cmd, sizeof(cmd), "Proxy-Authorization: Basic %s\r\n", t2);
                g_free(t2);
                if (send(source, cmd, strlen(cmd), 0) < 0) {
                        close(source);
                        phb->func(phb->data, -1, GAIM_INPUT_READ);
                        g_free(phb->host);
                        g_free(phb);
                        return;
                }
        }

        g_snprintf(cmd, sizeof(cmd), "\r\n");
        if (send(source, cmd, strlen(cmd), 0) < 0) {
                close(source);
                phb->func(phb->data, -1, GAIM_INPUT_READ);
                g_free(phb->host);
                g_free(phb);
                return;
        }

        phb->inpa = gaim_input_add(source, GAIM_INPUT_READ, http_canread, phb);
}

static int proxy_connect_http(const char *host, unsigned short port, struct PHB *phb)
{
        phb->host = g_strdup(host);
        phb->port = port;
        phb->proxy_func = http_canwrite;
        phb->proxy_data = phb;
        
        return( proxy_connect_none( proxyhost, proxyport, phb ) );
}


/* Connecting to SOCKS4 proxies */

static void s4_canread(gpointer data, gint source, GaimInputCondition cond)
{
        unsigned char packet[12];
        struct PHB *phb = data;

        gaim_input_remove(phb->inpa);

        memset(packet, 0, sizeof(packet));
        if (read(source, packet, 9) >= 4 && packet[1] == 90) {
                phb->func(phb->data, source, GAIM_INPUT_READ);
                g_free(phb->host);
                g_free(phb);
                return;
        }

        close(source);
        phb->func(phb->data, -1, GAIM_INPUT_READ);
        g_free(phb->host);
        g_free(phb);
}

static void s4_canwrite(gpointer data, gint source, GaimInputCondition cond)
{
        unsigned char packet[12];
        struct hostent *hp;
        struct PHB *phb = data;
        unsigned int len;
        int error = ETIMEDOUT;
        if (phb->inpa > 0)
                gaim_input_remove(phb->inpa);
        len = sizeof(error);
        if (getsockopt(source, SOL_SOCKET, SO_ERROR, &error, &len) < 0) {
                close(source);
                phb->func(phb->data, -1, GAIM_INPUT_READ);
                g_free(phb->host);
                g_free(phb);
                return;
        }
        sock_make_blocking(source);

        /* XXX does socks4 not support host name lookups by the proxy? */
        if (!(hp = gethostbyname(phb->host))) {
                close(source);
                phb->func(phb->data, -1, GAIM_INPUT_READ);
                g_free(phb->host);
                g_free(phb);
                return;
        }

        packet[0] = 4;
        packet[1] = 1;
        packet[2] = phb->port >> 8;
        packet[3] = phb->port & 0xff;
        packet[4] = (unsigned char)(hp->h_addr_list[0])[0];
        packet[5] = (unsigned char)(hp->h_addr_list[0])[1];
        packet[6] = (unsigned char)(hp->h_addr_list[0])[2];
        packet[7] = (unsigned char)(hp->h_addr_list[0])[3];
        packet[8] = 0;
        if (write(source, packet, 9) != 9) {
                close(source);
                phb->func(phb->data, -1, GAIM_INPUT_READ);
                g_free(phb->host);
                g_free(phb);
                return;
        }

        phb->inpa = gaim_input_add(source, GAIM_INPUT_READ, s4_canread, phb);
}

static int proxy_connect_socks4(const char *host, unsigned short port, struct PHB *phb)
{
        phb->host = g_strdup(host);
        phb->port = port;
        phb->proxy_func = s4_canwrite;
        phb->proxy_data = phb;
        
        return( proxy_connect_none( proxyhost, proxyport, phb ) );
}


/* Connecting to SOCKS5 proxies */

static void s5_canread_again(gpointer data, gint source, GaimInputCondition cond)
{
        unsigned char buf[512];
        struct PHB *phb = data;

        gaim_input_remove(phb->inpa);

        if (read(source, buf, 10) < 10) {
                close(source);
                phb->func(phb->data, -1, GAIM_INPUT_READ);
                g_free(phb->host);
                g_free(phb);
                return;
        }
        if ((buf[0] != 0x05) || (buf[1] != 0x00)) {
                close(source);
                phb->func(phb->data, -1, GAIM_INPUT_READ);
                g_free(phb->host);
                g_free(phb);
                return;
        }

        phb->func(phb->data, source, GAIM_INPUT_READ);
        g_free(phb->host);
        g_free(phb);
        return;
}

static void s5_sendconnect(gpointer data, gint source)
{
        unsigned char buf[512];
        struct PHB *phb = data;
        int hlen = strlen(phb->host);

        buf[0] = 0x05;
        buf[1] = 0x01;          /* CONNECT */
        buf[2] = 0x00;          /* reserved */
        buf[3] = 0x03;          /* address type -- host name */
        buf[4] = hlen;
        memcpy(buf + 5, phb->host, hlen);
        buf[5 + strlen(phb->host)] = phb->port >> 8;
        buf[5 + strlen(phb->host) + 1] = phb->port & 0xff;

        if (write(source, buf, (5 + strlen(phb->host) + 2)) < (5 + strlen(phb->host) + 2)) {
                close(source);
                phb->func(phb->data, -1, GAIM_INPUT_READ);
                g_free(phb->host);
                g_free(phb);
                return;
        }

        phb->inpa = gaim_input_add(source, GAIM_INPUT_READ, s5_canread_again, phb);
}

static void s5_readauth(gpointer data, gint source, GaimInputCondition cond)
{
        unsigned char buf[512];
        struct PHB *phb = data;

        gaim_input_remove(phb->inpa);

        if (read(source, buf, 2) < 2) {
                close(source);
                phb->func(phb->data, -1, GAIM_INPUT_READ);
                g_free(phb->host);
                g_free(phb);
                return;
        }

        if ((buf[0] != 0x01) || (buf[1] != 0x00)) {
                close(source);
                phb->func(phb->data, -1, GAIM_INPUT_READ);
                g_free(phb->host);
                g_free(phb);
                return;
        }

        s5_sendconnect(phb, source);
}

static void s5_canread(gpointer data, gint source, GaimInputCondition cond)
{
        unsigned char buf[512];
        struct PHB *phb = data;

        gaim_input_remove(phb->inpa);

        if (read(source, buf, 2) < 2) {
                close(source);
                phb->func(phb->data, -1, GAIM_INPUT_READ);
                g_free(phb->host);
                g_free(phb);
                return;
        }

        if ((buf[0] != 0x05) || (buf[1] == 0xff)) {
                close(source);
                phb->func(phb->data, -1, GAIM_INPUT_READ);
                g_free(phb->host);
                g_free(phb);
                return;
        }

        if (buf[1] == 0x02) {
                unsigned int i = strlen(proxyuser), j = strlen(proxypass);
                buf[0] = 0x01;  /* version 1 */
                buf[1] = i;
                memcpy(buf + 2, proxyuser, i);
                buf[2 + i] = j;
                memcpy(buf + 2 + i + 1, proxypass, j);
                if (write(source, buf, 3 + i + j) < 3 + i + j) {
                        close(source);
                        phb->func(phb->data, -1, GAIM_INPUT_READ);
                        g_free(phb->host);
                        g_free(phb);
                        return;
                }

                phb->inpa = gaim_input_add(source, GAIM_INPUT_READ, s5_readauth, phb);
        } else {
                s5_sendconnect(phb, source);
        }
}

static void s5_canwrite(gpointer data, gint source, GaimInputCondition cond)
{
        unsigned char buf[512];
        int i;
        struct PHB *phb = data;
        unsigned int len;
        int error = ETIMEDOUT;
        if (phb->inpa > 0)
                gaim_input_remove(phb->inpa);
        len = sizeof(error);
        if (getsockopt(source, SOL_SOCKET, SO_ERROR, &error, &len) < 0) {
                close(source);
                phb->func(phb->data, -1, GAIM_INPUT_READ);
                g_free(phb->host);
                g_free(phb);
                return;
        }
        sock_make_blocking(source);

        i = 0;
        buf[0] = 0x05;          /* SOCKS version 5 */
        if (proxyuser[0]) {
                buf[1] = 0x02;  /* two methods */
                buf[2] = 0x00;  /* no authentication */
                buf[3] = 0x02;  /* username/password authentication */
                i = 4;
        } else {
                buf[1] = 0x01;
                buf[2] = 0x00;
                i = 3;
        }

        if (write(source, buf, i) < i) {
                close(source);
                phb->func(phb->data, -1, GAIM_INPUT_READ);
                g_free(phb->host);
                g_free(phb);
                return;
        }

        phb->inpa = gaim_input_add(source, GAIM_INPUT_READ, s5_canread, phb);
}

static int proxy_connect_socks5(const char *host, unsigned short port, struct PHB *phb)
{
        phb->host = g_strdup(host);
        phb->port = port;
        phb->proxy_func = s5_canwrite;
        phb->proxy_data = phb;
        
        return( proxy_connect_none( proxyhost, proxyport, phb ) );
}


/* Export functions */

gint gaim_input_add(gint source, GaimInputCondition condition, GaimInputFunction function, gpointer data)
{
        GaimIOClosure *closure = g_new0(GaimIOClosure, 1);
        GIOChannel *channel;
        GIOCondition cond = 0;
        
        closure->function = function;
        closure->data = data;
        
        if (condition & GAIM_INPUT_READ)
                cond |= GAIM_READ_COND;
        if (condition & GAIM_INPUT_WRITE)
                cond |= GAIM_WRITE_COND;
        
        channel = g_io_channel_unix_new(source);
        closure->result = g_io_add_watch_full(channel, G_PRIORITY_DEFAULT, cond,
                                              gaim_io_invoke, closure, gaim_io_destroy);
        
        g_io_channel_unref(channel);
        return closure->result;
}

void gaim_input_remove(gint tag)
{
        if (tag > 0)
                g_source_remove(tag);
}

int proxy_connect(const char *host, int port, GaimInputFunction func, gpointer data)
{
        struct PHB *phb;
        
        if (!host || !port || (port == -1) || !func || strlen(host) > 128) {
                return -1;
        }
        
        phb = g_new0(struct PHB, 1);
        phb->func = func;
        phb->data = data;
        
#ifndef _WIN32
        sethostent(1);
#endif
        
        if ((proxytype == PROXY_NONE) || !proxyhost || !proxyhost[0] || !proxyport || (proxyport == -1))
                return proxy_connect_none(host, port, phb);
        else if (proxytype == PROXY_HTTP)
                return proxy_connect_http(host, port, phb);
        else if (proxytype == PROXY_SOCKS4)
                return proxy_connect_socks4(host, port, phb);
        else if (proxytype == PROXY_SOCKS5)
                return proxy_connect_socks5(host, port, phb);
        
        if (phb->host) g_free(phb);
        g_free(phb);
        return -1;
}