vl.c

qemu虚拟机代码

        for(j=0;j<len;j++) {
            c = buf[i+j];
            if (c < ' ' || c > '~')
                c = '.';
            fprintf(f, "%c", c);
        }
        fprintf(f, "\n");
    }
}

static int parse_macaddr(uint8_t *macaddr, const char *p)
{
    int i;
    for(i = 0; i < 6; i++) {
        macaddr[i] = strtol(p, (char **)&p, 16);
        if (i == 5) {
            if (*p != '\0') 
                return -1;
        } else {
            if (*p != ':') 
                return -1;
            p++;
        }
    }
    return 0;
}

static int get_str_sep(char *buf, int buf_size, const char **pp, int sep)
{
    const char *p, *p1;
    int len;
    p = *pp;
    p1 = strchr(p, sep);
    if (!p1)
        return -1;
    len = p1 - p;
    p1++;
    if (buf_size > 0) {
        if (len > buf_size - 1)
            len = buf_size - 1;
        memcpy(buf, p, len);
        buf[len] = '\0';
    }
    *pp = p1;
    return 0;
}

int parse_host_port(struct sockaddr_in *saddr, const char *str)
{
    char buf[512];
    struct hostent *he;
    const char *p, *r;
    int port;

    p = str;
    if (get_str_sep(buf, sizeof(buf), &p, ':') < 0)
        return -1;
    saddr->sin_family = AF_INET;
    if (buf[0] == '\0') {
        saddr->sin_addr.s_addr = 0;
    } else {
        if (isdigit(buf[0])) {
            if (!inet_aton(buf, &saddr->sin_addr))
                return -1;
        } else {
            if ((he = gethostbyname(buf)) == NULL)
                return - 1;
            saddr->sin_addr = *(struct in_addr *)he->h_addr;
        }
    }
    port = strtol(p, (char **)&r, 0);
    if (r == p)
        return -1;
    saddr->sin_port = htons(port);
    return 0;
}

/* find or alloc a new VLAN */
VLANState *qemu_find_vlan(int id)
{
    VLANState **pvlan, *vlan;
    for(vlan = first_vlan; vlan != NULL; vlan = vlan->next) {
        if (vlan->id == id)
            return vlan;
    }
    vlan = qemu_mallocz(sizeof(VLANState));
    if (!vlan)
        return NULL;
    vlan->id = id;
    vlan->next = NULL;
    pvlan = &first_vlan;
    while (*pvlan != NULL)
        pvlan = &(*pvlan)->next;
    *pvlan = vlan;
    return vlan;
}

VLANClientState *qemu_new_vlan_client(VLANState *vlan,
                                      IOReadHandler *fd_read,
                                      IOCanRWHandler *fd_can_read,
                                      void *opaque)
{
    VLANClientState *vc, **pvc;
    vc = qemu_mallocz(sizeof(VLANClientState));
    if (!vc)
        return NULL;
    vc->fd_read = fd_read;
    vc->fd_can_read = fd_can_read;
    vc->opaque = opaque;
    vc->vlan = vlan;

    vc->next = NULL;
    pvc = &vlan->first_client;
    while (*pvc != NULL)
        pvc = &(*pvc)->next;
    *pvc = vc;
    return vc;
}

int qemu_can_send_packet(VLANClientState *vc1)
{
    VLANState *vlan = vc1->vlan;
    VLANClientState *vc;

    for(vc = vlan->first_client; vc != NULL; vc = vc->next) {
        if (vc != vc1) {
            if (vc->fd_can_read && !vc->fd_can_read(vc->opaque))
                return 0;
        }
    }
    return 1;
}

void qemu_send_packet(VLANClientState *vc1, const uint8_t *buf, int size)
{
    VLANState *vlan = vc1->vlan;
    VLANClientState *vc;

#if 0
    printf("vlan %d send:\n", vlan->id);
    hex_dump(stdout, buf, size);
#endif
    for(vc = vlan->first_client; vc != NULL; vc = vc->next) {
        if (vc != vc1) {
            vc->fd_read(vc->opaque, buf, size);
        }
    }
}

#if defined(CONFIG_SLIRP)

/* slirp network adapter */

static int slirp_inited;
static VLANClientState *slirp_vc;

int slirp_can_output(void)
{
    return !slirp_vc || qemu_can_send_packet(slirp_vc);
}

void slirp_output(const uint8_t *pkt, int pkt_len)
{
#if 0
    printf("slirp output:\n");
    hex_dump(stdout, pkt, pkt_len);
#endif
    if (!slirp_vc)
        return;
    qemu_send_packet(slirp_vc, pkt, pkt_len);
}

static void slirp_receive(void *opaque, const uint8_t *buf, int size)
{
#if 0
    printf("slirp input:\n");
    hex_dump(stdout, buf, size);
#endif
    slirp_input(buf, size);
}

static int net_slirp_init(VLANState *vlan)
{
    if (!slirp_inited) {
        slirp_inited = 1;
        slirp_init();
    }
    slirp_vc = qemu_new_vlan_client(vlan, 
                                    slirp_receive, NULL, NULL);
    snprintf(slirp_vc->info_str, sizeof(slirp_vc->info_str), "user redirector");
    return 0;
}

static void net_slirp_redir(const char *redir_str)
{
    int is_udp;
    char buf[256], *r;
    const char *p;
    struct in_addr guest_addr;
    int host_port, guest_port;
    
    if (!slirp_inited) {
        slirp_inited = 1;
        slirp_init();
    }

    p = redir_str;
    if (get_str_sep(buf, sizeof(buf), &p, ':') < 0)
        goto fail;
    if (!strcmp(buf, "tcp")) {
        is_udp = 0;
    } else if (!strcmp(buf, "udp")) {
        is_udp = 1;
    } else {
        goto fail;
    }

    if (get_str_sep(buf, sizeof(buf), &p, ':') < 0)
        goto fail;
    host_port = strtol(buf, &r, 0);
    if (r == buf)
        goto fail;

    if (get_str_sep(buf, sizeof(buf), &p, ':') < 0)
        goto fail;
    if (buf[0] == '\0') {
        pstrcpy(buf, sizeof(buf), "10.0.2.15");
    }
    if (!inet_aton(buf, &guest_addr))
        goto fail;
    
    guest_port = strtol(p, &r, 0);
    if (r == p)
        goto fail;
    
    if (slirp_redir(is_udp, host_port, guest_addr, guest_port) < 0) {
        fprintf(stderr, "qemu: could not set up redirection\n");
        exit(1);
    }
    return;
 fail:
    fprintf(stderr, "qemu: syntax: -redir [tcp|udp]:host-port:[guest-host]:guest-port\n");
    exit(1);
}
    
#ifndef _WIN32

char smb_dir[1024];

static void smb_exit(void)
{
    DIR *d;
    struct dirent *de;
    char filename[1024];

    /* erase all the files in the directory */
    d = opendir(smb_dir);
    for(;;) {
        de = readdir(d);
        if (!de)
            break;
        if (strcmp(de->d_name, ".") != 0 &&
            strcmp(de->d_name, "..") != 0) {
            snprintf(filename, sizeof(filename), "%s/%s", 
                     smb_dir, de->d_name);
            unlink(filename);
        }
    }
    closedir(d);
    rmdir(smb_dir);
}

/* automatic user mode samba server configuration */
void net_slirp_smb(const char *exported_dir)
{
    char smb_conf[1024];
    char smb_cmdline[1024];
    FILE *f;

    if (!slirp_inited) {
        slirp_inited = 1;
        slirp_init();
    }

    /* XXX: better tmp dir construction */
    snprintf(smb_dir, sizeof(smb_dir), "/tmp/qemu-smb.%d", getpid());
    if (mkdir(smb_dir, 0700) < 0) {
        fprintf(stderr, "qemu: could not create samba server dir '%s'\n", smb_dir);
        exit(1);
    }
    snprintf(smb_conf, sizeof(smb_conf), "%s/%s", smb_dir, "smb.conf");
    
    f = fopen(smb_conf, "w");
    if (!f) {
        fprintf(stderr, "qemu: could not create samba server configuration file '%s'\n", smb_conf);
        exit(1);
    }
    fprintf(f, 
            "[global]\n"
            "private dir=%s\n"
            "smb ports=0\n"
            "socket address=127.0.0.1\n"
            "pid directory=%s\n"
            "lock directory=%s\n"
            "log file=%s/log.smbd\n"
            "smb passwd file=%s/smbpasswd\n"
            "security = share\n"
            "[qemu]\n"
            "path=%s\n"
            "read only=no\n"
            "guest ok=yes\n",
            smb_dir,
            smb_dir,
            smb_dir,
            smb_dir,
            smb_dir,
            exported_dir
            );
    fclose(f);
    atexit(smb_exit);

    snprintf(smb_cmdline, sizeof(smb_cmdline), "/usr/sbin/smbd -s %s",
             smb_conf);
    
    slirp_add_exec(0, smb_cmdline, 4, 139);
}

#endif /* !defined(_WIN32) */

#endif /* CONFIG_SLIRP */

#if !defined(_WIN32)

typedef struct TAPState {
    VLANClientState *vc;
    int fd;
} TAPState;

static void tap_receive(void *opaque, const uint8_t *buf, int size)
{
    TAPState *s = opaque;
    int ret;
    for(;;) {
        ret = write(s->fd, buf, size);
        if (ret < 0 && (errno == EINTR || errno == EAGAIN)) {
        } else {
            break;
        }
    }
}

static void tap_send(void *opaque)
{
    TAPState *s = opaque;
    uint8_t buf[4096];
    int size;

    size = read(s->fd, buf, sizeof(buf));
    if (size > 0) {
        qemu_send_packet(s->vc, buf, size);
    }
}

/* fd support */

static TAPState *net_tap_fd_init(VLANState *vlan, int fd)
{
    TAPState *s;

    s = qemu_mallocz(sizeof(TAPState));
    if (!s)
        return NULL;
    s->fd = fd;
    s->vc = qemu_new_vlan_client(vlan, tap_receive, NULL, s);
    qemu_set_fd_handler(s->fd, tap_send, NULL, s);
    snprintf(s->vc->info_str, sizeof(s->vc->info_str), "tap: fd=%d", fd);
    return s;
}

#ifdef _BSD
static int tap_open(char *ifname, int ifname_size)
{
    int fd;
    char *dev;
    struct stat s;

    fd = open("/dev/tap", O_RDWR);
    if (fd < 0) {
        fprintf(stderr, "warning: could not open /dev/tap: no virtual network emulation\n");
        return -1;
    }

    fstat(fd, &s);
    dev = devname(s.st_rdev, S_IFCHR);
    pstrcpy(ifname, ifname_size, dev);

    fcntl(fd, F_SETFL, O_NONBLOCK);
    return fd;
}
#elif defined(__sun__)
static int tap_open(char *ifname, int ifname_size)
{
    fprintf(stderr, "warning: tap_open not yet implemented\n");
    return -1;
}
#else
static int tap_open(char *ifname, int ifname_size)
{
    struct ifreq ifr;
    int fd, ret;
    
    fd = open("/dev/net/tun", O_RDWR);
    if (fd < 0) {
        fprintf(stderr, "warning: could not open /dev/net/tun: no virtual network emulation\n");
        return -1;
    }
    memset(&ifr, 0, sizeof(ifr));
    ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
    if (ifname[0] != '\0')
        pstrcpy(ifr.ifr_name, IFNAMSIZ, ifname);
    else
        pstrcpy(ifr.ifr_name, IFNAMSIZ, "tap%d");
    ret = ioctl(fd, TUNSETIFF, (void *) &ifr);
    if (ret != 0) {
        fprintf(stderr, "warning: could not configure /dev/net/tun: no virtual network emulation\n");
        close(fd);
        return -1;
    }
    pstrcpy(ifname, ifname_size, ifr.ifr_name);
    fcntl(fd, F_SETFL, O_NONBLOCK);
    return fd;
}
#endif

static int net_tap_init(VLANState *vlan, const char *ifname1,
                        const char *setup_script)
{
    TAPState *s;
    int pid, status, fd;
    char *args[3];
    char **parg;
    char ifname[128];

    if (ifname1 != NULL)
        pstrcpy(ifname, sizeof(ifname), ifname1);
    else
        ifname[0] = '\0';
    fd = tap_open(ifname, sizeof(ifname));
    if (fd < 0)
        return -1;

    if (!setup_script)
        setup_script = "";
    if (setup_script[0] != '\0') {
        /* try to launch network init script */
        pid = fork();
        if (pid >= 0) {
            if (pid == 0) {
                parg = args;
                *parg++ = (char *)setup_script;
                *parg++ = ifname;
                *parg++ = NULL;
                execv(setup_script, args);
                _exit(1);
            }
            while (waitpid(pid, &status, 0) != pid);
            if (!WIFEXITED(status) ||
                WEXITSTATUS(status) != 0) {
                fprintf(stderr, "%s: could not launch network script\n",
                        setup_script);
                return -1;
            }
        }
    }
    s = net_tap_fd_init(vlan, fd);
    if (!s)
        return -1;
    snprintf(s->vc->info_str, sizeof(s->vc->info_str), 
             "tap: ifname=%s setup_script=%s", ifname, setup_script);
    return 0;
}

#endif /* !_WIN32 */

/* network connection */
typedef struct NetSocketState {
    VLANClientState *vc;
    int fd;
    int state; /* 0 = getting length, 1 = getting data */
    int index;
    int packet_len;
    uint8_t buf[4096];
    struct sockaddr_in dgram_dst; /* contains inet host and port destination iff connectionless (SOCK_DGRAM) */
} NetSocketState;

typedef struct NetSocketListenState {
    VLANState *vlan;
    int fd;
} NetSocketListenState;

/* XXX: we consider we can send the whole packet without blocking */
static void net_socket_receive(void *opaque, const uint8_t *buf, int size)
{
    NetSocketState *s = opaque;
    uint32_t len;
    len = htonl(size);

    send_all(s->fd, (const uint8_t *)&len, sizeof(len));
    send_all(s->fd, buf, size);
}

static void net_socket_receive_dgram(void *opaque, const uint8_t *buf, int size)
{
    NetSocketState *s = opaque;
    sendto(s->fd, buf, size, 0, 
           (struct sockaddr *)&s->dgram_dst, sizeof(s->dgram_dst));
}

static void net_socket_send(void *opaque)
{
    NetSocketState *s = opaque;
    int l, size, err;
    uint8_t buf1[4096];
    const uint8_t *buf;

    size = recv(s->fd, buf1, sizeof(buf1), 0);
    if (size < 0) {
        err = socket_error();
        if (err != EWOULDBLOCK) 
            goto eoc;
    } else if (size == 0) {
        /* end of connection */
    eoc:
        qemu_set_fd_handler(s->fd, NULL, NULL, NULL);
        closesocket(s->fd);
        return;
    }
    buf = buf1;
    while (size > 0) {
        /* reassemble a packet from the network */
        switch(s->state) {
        case 0:
            l = 4 - s->index;