NAME¶

vdeslirp_open, vdeslirp_send, vdeslirp_recv, vdeslirp_fd, vdeslirp_close - simple API for slirp

SYNOPSIS¶

#include <libvdeslirp.h>

struct vdeslirp *vdeslirp_open(SlirpConfig *cfg);

ssize_t vdeslirp_send(struct vdeslirp *slirp, const void *buf, size_t count);

ssize_t vdeslirp_recv(struct vdeslirp *slirp, void *buf, size_t count);

int vdeslirp_fd(struct vdeslirp *slirp);

int vdeslirp_close(struct vdeslirp *slirp);

These functions are provided by libvdeslirp. Link with -lvdeslirp.

DESCRIPTION¶

Slirp is a TCP/IP emulator. Slirp generates a virtual network using standard user privileges (no need for root access of CAP_NET_ADMIN). This implementation uses libslirp.

vdeslirp_open creates a slirp network. The SlirpConfig structure is defined by libslirp and contains the following fields:

typedef struct SlirpConfig {


    /* Version must be provided */


    uint32_t version;


    /*


     * Fields introduced in SlirpConfig version 1 begin


     */


    int restricted;


    bool in_enabled;


    struct in_addr vnetwork;


    struct in_addr vnetmask;


    struct in_addr vhost;


    bool in6_enabled;


    struct in6_addr vprefix_addr6;


    uint8_t vprefix_len;


    struct in6_addr vhost6;


    const char *vhostname;


    const char *tftp_server_name;


    const char *tftp_path;


    const char *bootfile;


    struct in_addr vdhcp_start;


    struct in_addr vnameserver;


    struct in6_addr vnameserver6;


    const char **vdnssearch;


    const char *vdomainname;


    /* Default: IF_MTU_DEFAULT */


    size_t if_mtu;


    /* Default: IF_MRU_DEFAULT */


    size_t if_mru;


    /* Prohibit connecting to 127.0.0.1:* */


    bool disable_host_loopback;


    /*


     * Enable emulation code (*warning*: this code isn´t safe, it is not


     * recommended to enable it)


     */


    bool enable_emu;


    /*


     * Fields introduced in SlirpConfig version 2 begin


     */
} SlirpConfig;

libvdeslirp provides helper functions to fill in the fields of this structure, see libvdeslirpcfg(3).

Programs using libvdeslirp can send and receive packets using vdeslirp_send and vdeslirp_recv as if they were connected to host network (commonly the Internet) by a NAT/Masquerading router. vdeslirp_fd provides a valid file descriptor which can be used to wait for incoming packets (using select or poll) and vdeslirp_close terminates a slirp network created by vdeslirp_open.

RETURN VALUE¶

vdeslirp_open returns the struct vdeslirp pointer in case of success. NULL is returned otherwise. The return value of vdeslirp_open is the descriptor that must be passed as first argument to all the other functions of this man page. vdeslirp_send and vdeslirp_recv return the number of bytes sent or received, -1 in case of error. vdeslirp_fd returns a valid file descriptor which can be used to wait for incoming packets (using select or poll). vdeslirp_close returns zero in case of success, -1 in case of error. In case of failure, errno is set to indicate the type of error.

SEE ALSO¶

libvdeslirpfwd(3), libvdeslirpcfg(3)

BUGS¶

Bug reports should be addressed to <info@virtualsquare.org>

AUTHOR¶

VirtualSquare. Project leader: Renzo Davoli.