Archipelago » qemu

/*

 *  inet and unix socket functions for qemu

 *

 *  (c) 2008 Gerd Hoffmann <kraxel@redhat.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; under version 2 of the License.

 *

 *  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.

 */

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <ctype.h>

#include <errno.h>

#include <unistd.h>

#include "qemu_socket.h"

#include "qemu-common.h" /* for qemu_isdigit */

#ifndef AI_ADDRCONFIG

# define AI_ADDRCONFIG 0

#endif

static int sockets_debug = 0;

static const int on=1, off=0;

static int inet_getport(struct addrinfo *e)

{

    struct sockaddr_in *i4;

    struct sockaddr_in6 *i6;

    switch (e->ai_family) {

    case PF_INET6:

        i6 = (void*)e->ai_addr;

        return ntohs(i6->sin6_port);

    case PF_INET:

        i4 = (void*)e->ai_addr;

        return ntohs(i4->sin_port);

    default:

        return 0;

    }

}

static void inet_setport(struct addrinfo *e, int port)

{

    struct sockaddr_in *i4;

    struct sockaddr_in6 *i6;

    switch (e->ai_family) {

    case PF_INET6:

        i6 = (void*)e->ai_addr;

        i6->sin6_port = htons(port);

        break;

    case PF_INET:

        i4 = (void*)e->ai_addr;

        i4->sin_port = htons(port);

        break;

    }

}

static const char *inet_strfamily(int family)

{

    switch (family) {

    case PF_INET6: return "ipv6";

    case PF_INET:  return "ipv4";

    case PF_UNIX:  return "unix";

    }

    return "????";

}

static void inet_print_addrinfo(const char *tag, struct addrinfo *res)

{

    struct addrinfo *e;

    char uaddr[INET6_ADDRSTRLEN+1];

    char uport[33];

    for (e = res; e != NULL; e = e->ai_next) {

        getnameinfo((struct sockaddr*)e->ai_addr,e->ai_addrlen,

                    uaddr,INET6_ADDRSTRLEN,uport,32,

                    NI_NUMERICHOST | NI_NUMERICSERV);

        fprintf(stderr,"%s: getaddrinfo: family %s, host %s, port %s\n",

                tag, inet_strfamily(e->ai_family), uaddr, uport);

    }

}

int inet_listen(const char *str, char *ostr, int olen,

                int socktype, int port_offset)

{

    struct addrinfo ai,*res,*e;

    char addr[64];

    char port[33];

    char uaddr[INET6_ADDRSTRLEN+1];

    char uport[33];

    const char *opts, *h;

    int slisten,rc,pos,to,try_next;

    memset(&ai,0, sizeof(ai));

    ai.ai_flags = AI_PASSIVE | AI_ADDRCONFIG;

    ai.ai_family = PF_UNSPEC;

    ai.ai_socktype = socktype;

    /* parse address */

    if (str[0] == ':') {

        /* no host given */

        addr[0] = '\0';

        if (1 != sscanf(str,":%32[^,]%n",port,&pos)) {

            fprintf(stderr, "%s: portonly parse error (%s)\n",

                    __FUNCTION__, str);

            return -1;

        }

    } else if (str[0] == '[') {

        /* IPv6 addr */

        if (2 != sscanf(str,"[%64[^]]]:%32[^,]%n",addr,port,&pos)) {

            fprintf(stderr, "%s: ipv6 parse error (%s)\n",

                    __FUNCTION__, str);

            return -1;

        }

        ai.ai_family = PF_INET6;

    } else if (qemu_isdigit(str[0])) {

        /* IPv4 addr */

        if (2 != sscanf(str,"%64[0-9.]:%32[^,]%n",addr,port,&pos)) {

            fprintf(stderr, "%s: ipv4 parse error (%s)\n",

                    __FUNCTION__, str);

            return -1;

        }

        ai.ai_family = PF_INET;

    } else {

        /* hostname */

        if (2 != sscanf(str,"%64[^:]:%32[^,]%n",addr,port,&pos)) {

            fprintf(stderr, "%s: hostname parse error (%s)\n",

                    __FUNCTION__, str);

            return -1;

        }

    }

    /* parse options */

    opts = str + pos;

    h = strstr(opts, ",to=");

    to = h ? atoi(h+4) : 0;

    if (strstr(opts, ",ipv4"))

        ai.ai_family = PF_INET;

    if (strstr(opts, ",ipv6"))

        ai.ai_family = PF_INET6;

    /* lookup */

    if (port_offset)

        snprintf(port, sizeof(port), "%d", atoi(port) + port_offset);

    rc = getaddrinfo(strlen(addr) ? addr : NULL, port, &ai, &res);

    if (rc != 0) {

        fprintf(stderr,"%s: getaddrinfo(%s,%s): %s\n", __FUNCTION__,

                addr, port, gai_strerror(rc));

        return -1;

    }

    if (sockets_debug)

        inet_print_addrinfo(__FUNCTION__, res);

    /* create socket + bind */

    for (e = res; e != NULL; e = e->ai_next) {

        getnameinfo((struct sockaddr*)e->ai_addr,e->ai_addrlen,

                    uaddr,INET6_ADDRSTRLEN,uport,32,

                    NI_NUMERICHOST | NI_NUMERICSERV);

        slisten = socket(e->ai_family, e->ai_socktype, e->ai_protocol);

        if (slisten < 0) {

            fprintf(stderr,"%s: socket(%s): %s\n", __FUNCTION__,

                    inet_strfamily(e->ai_family), strerror(errno));

            continue;

        }

        setsockopt(slisten,SOL_SOCKET,SO_REUSEADDR,(void*)&on,sizeof(on));

#ifdef IPV6_V6ONLY

        if (e->ai_family == PF_INET6) {

            /* listen on both ipv4 and ipv6 */

            setsockopt(slisten,IPPROTO_IPV6,IPV6_V6ONLY,(void*)&off,sizeof(off));

        }

#endif

        for (;;) {

            if (bind(slisten, e->ai_addr, e->ai_addrlen) == 0) {

                if (sockets_debug)

                    fprintf(stderr,"%s: bind(%s,%s,%d): OK\n", __FUNCTION__,

                            inet_strfamily(e->ai_family), uaddr, inet_getport(e));

                goto listen;

            }

            try_next = to && (inet_getport(e) <= to + port_offset);

            if (!try_next || sockets_debug)

                fprintf(stderr,"%s: bind(%s,%s,%d): %s\n", __FUNCTION__,

                        inet_strfamily(e->ai_family), uaddr, inet_getport(e),

                        strerror(errno));

            if (try_next) {

                inet_setport(e, inet_getport(e) + 1);

                continue;

            }

            break;

        }

        closesocket(slisten);

    }

    fprintf(stderr, "%s: FAILED\n", __FUNCTION__);

    freeaddrinfo(res);

    return -1;

listen:

    if (listen(slisten,1) != 0) {

        perror("listen");

        closesocket(slisten);

        return -1;

    }

    if (ostr) {

        if (e->ai_family == PF_INET6) {

            snprintf(ostr, olen, "[%s]:%d%s", uaddr,

                     inet_getport(e) - port_offset, opts);

        } else {

            snprintf(ostr, olen, "%s:%d%s", uaddr,

                     inet_getport(e) - port_offset, opts);

        }

    }

    freeaddrinfo(res);

    return slisten;

}

int inet_connect(const char *str, int socktype)

{

    struct addrinfo ai,*res,*e;

    char addr[64];

    char port[33];

    char uaddr[INET6_ADDRSTRLEN+1];

    char uport[33];

    int sock,rc;

    memset(&ai,0, sizeof(ai));

    ai.ai_flags = AI_CANONNAME | AI_ADDRCONFIG;

    ai.ai_family = PF_UNSPEC;

    ai.ai_socktype = socktype;

    /* parse address */

    if (str[0] == '[') {

        /* IPv6 addr */

        if (2 != sscanf(str,"[%64[^]]]:%32[^,]",addr,port)) {

            fprintf(stderr, "%s: ipv6 parse error (%s)\n",

                    __FUNCTION__, str);

            return -1;

        }

        ai.ai_family = PF_INET6;

    } else if (qemu_isdigit(str[0])) {

        /* IPv4 addr */

        if (2 != sscanf(str,"%64[0-9.]:%32[^,]",addr,port)) {

            fprintf(stderr, "%s: ipv4 parse error (%s)\n",

                    __FUNCTION__, str);

            return -1;

        }

        ai.ai_family = PF_INET;

    } else {

        /* hostname */

        if (2 != sscanf(str,"%64[^:]:%32[^,]",addr,port)) {

            fprintf(stderr, "%s: hostname parse error (%s)\n",

                    __FUNCTION__, str);

            return -1;

        }

    }

    /* parse options */

    if (strstr(str, ",ipv4"))

        ai.ai_family = PF_INET;

    if (strstr(str, ",ipv6"))

        ai.ai_family = PF_INET6;

    /* lookup */

    if (0 != (rc = getaddrinfo(addr, port, &ai, &res))) {

        fprintf(stderr,"getaddrinfo(%s,%s): %s\n", gai_strerror(rc),

                addr, port);

        return -1;

    }

    if (sockets_debug)

        inet_print_addrinfo(__FUNCTION__, res);

    for (e = res; e != NULL; e = e->ai_next) {

        if (getnameinfo((struct sockaddr*)e->ai_addr,e->ai_addrlen,

                        uaddr,INET6_ADDRSTRLEN,uport,32,

                        NI_NUMERICHOST | NI_NUMERICSERV) != 0) {

            fprintf(stderr,"%s: getnameinfo: oops\n", __FUNCTION__);

            continue;

        }

        sock = socket(e->ai_family, e->ai_socktype, e->ai_protocol);

        if (sock < 0) {

            fprintf(stderr,"%s: socket(%s): %s\n", __FUNCTION__,

                    inet_strfamily(e->ai_family), strerror(errno));

            continue;

        }

        setsockopt(sock,SOL_SOCKET,SO_REUSEADDR,(void*)&on,sizeof(on));

        /* connect to peer */

        if (connect(sock,e->ai_addr,e->ai_addrlen) < 0) {

            if (sockets_debug || NULL == e->ai_next)

                fprintf(stderr, "%s: connect(%s,%s,%s,%s): %s\n", __FUNCTION__,

                        inet_strfamily(e->ai_family),

                        e->ai_canonname, uaddr, uport, strerror(errno));

            closesocket(sock);

            continue;

        }

        if (sockets_debug)

            fprintf(stderr, "%s: connect(%s,%s,%s,%s): OK\n", __FUNCTION__,

                    inet_strfamily(e->ai_family),

                    e->ai_canonname, uaddr, uport);

        freeaddrinfo(res);

        return sock;

    }

    freeaddrinfo(res);

    return -1;

}

#ifndef _WIN32

int unix_listen(const char *str, char *ostr, int olen)

{

    struct sockaddr_un un;

    char *path, *opts;

    int sock, fd, len;

    sock = socket(PF_UNIX, SOCK_STREAM, 0);

    if (sock < 0) {

        perror("socket(unix)");

        return -1;

    }

    opts = strchr(str, ',');

    if (opts) {

        len = opts - str;

        path = malloc(len+1);

        snprintf(path, len+1, "%.*s", len, str);

    } else

        path = strdup(str);

    memset(&un, 0, sizeof(un));

    un.sun_family = AF_UNIX;

    if (path && strlen(path)) {

        snprintf(un.sun_path, sizeof(un.sun_path), "%s", path);

    } else {

        char *tmpdir = getenv("TMPDIR");

        snprintf(un.sun_path, sizeof(un.sun_path), "%s/qemu-socket-XXXXXX",

                 tmpdir ? tmpdir : "/tmp");

        /*

         * This dummy fd usage silences the mktemp() unsecure warning.

         * Using mkstemp() doesn't make things more secure here

         * though.  bind() complains about existing files, so we have

         * to unlink first and thus re-open the race window.  The

         * worst case possible is bind() failing, i.e. a DoS attack.

         */

        fd = mkstemp(un.sun_path); close(fd);

    }

    snprintf(ostr, olen, "%s%s", un.sun_path, opts ? opts : "");

    unlink(un.sun_path);

    if (bind(sock, (struct sockaddr*) &un, sizeof(un)) < 0) {

        fprintf(stderr, "bind(unix:%s): %s\n", un.sun_path, strerror(errno));

        goto err;

    }

    if (listen(sock, 1) < 0) {

        fprintf(stderr, "listen(unix:%s): %s\n", un.sun_path, strerror(errno));

        goto err;

    }

    if (sockets_debug)

        fprintf(stderr, "bind(unix:%s): OK\n", un.sun_path);

    free(path);

    return sock;

err:

    free(path);

    closesocket(sock);

    return -1;

}

int unix_connect(const char *path)

{

    struct sockaddr_un un;

    int sock;

    sock = socket(PF_UNIX, SOCK_STREAM, 0);

    if (sock < 0) {

        perror("socket(unix)");

        return -1;

    }

    memset(&un, 0, sizeof(un));

    un.sun_family = AF_UNIX;

    snprintf(un.sun_path, sizeof(un.sun_path), "%s", path);

    if (connect(sock, (struct sockaddr*) &un, sizeof(un)) < 0) {

        fprintf(stderr, "connect(unix:%s): %s\n", path, strerror(errno));

        return -1;

    }

    if (sockets_debug)

        fprintf(stderr, "connect(unix:%s): OK\n", path);

    return sock;

}

#else

int unix_listen(const char *path, char *ostr, int olen)

{

    fprintf(stderr, "unix sockets are not available on windows\n");

    return -1;

}

int unix_connect(const char *path)

{

    fprintf(stderr, "unix sockets are not available on windows\n");

    return -1;

}

#endif