/* Copyright (c) 2008 The Board of Trustees of The Leland Stanford
 * Junior University
 * 
 * We are making the OpenFlow specification and associated documentation
 * (Software) available for public use and benefit with the expectation
 * that others will use, modify and enhance the Software and contribute
 * those enhancements back to the community. However, since we would
 * like to make the Software available for broadest use, with as few
 * restrictions as possible permission is hereby granted, free of
 * charge, to any person obtaining a copy of this Software to deal in
 * the Software under the copyrights without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 * 
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT.  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 * 
 * The name and trademarks of copyright holder(s) may NOT be used in
 * advertising or publicity pertaining to the Software or any
 * derivatives without specific, written prior permission.
 */

#include <config.h>
#include "vconn.h"
#include <errno.h>
#include <inttypes.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "packets.h"
#include "socket-util.h"
#include "util.h"
#include "openflow/openflow.h"
#include "vconn-provider.h"
#include "vconn-stream.h"

#include "vlog.h"
#define THIS_MODULE VLM_vconn_tcp

/* Active TCP. */

static int
new_tcp_vconn(const char *name, int fd, int connect_status,
              const struct sockaddr_in *sin, struct vconn **vconnp)
{
    int on = 1;
    int retval;

    retval = setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &on, sizeof on);
    if (retval) {
        VLOG_ERR("%s: setsockopt(TCP_NODELAY): %s", name, strerror(errno));
        close(fd);
        return errno;
    }

    return new_stream_vconn(name, fd, connect_status, sin->sin_addr.s_addr,
                            vconnp);
}

static int
tcp_open(const char *name, char *suffix, struct vconn **vconnp)
{
    char *save_ptr;
    const char *host_name;
    const char *port_string;
    struct sockaddr_in sin;
    int retval;
    int fd;

    /* Glibc 2.7 has a bug in strtok_r when compiling with optimization that
     * can cause segfaults here:
     * http://sources.redhat.com/bugzilla/show_bug.cgi?id=5614.
     * Using "::" instead of the obvious ":" works around it. */
    host_name = strtok_r(suffix, "::", &save_ptr);
    port_string = strtok_r(NULL, "::", &save_ptr);
    if (!host_name) {
        ofp_error(0, "%s: bad peer name format", name);
        return EAFNOSUPPORT;
    }

    memset(&sin, 0, sizeof sin);
    sin.sin_family = AF_INET;
    if (lookup_ip(host_name, &sin.sin_addr)) {
        return ENOENT;
    }
    sin.sin_port = htons(port_string ? atoi(port_string) : OFP_TCP_PORT);

    fd = socket(AF_INET, SOCK_STREAM, 0);
    if (fd < 0) {
        VLOG_ERR("%s: socket: %s", name, strerror(errno));
        return errno;
    }

    retval = set_nonblocking(fd);
    if (retval) {
        close(fd);
        return retval;
    }

    retval = connect(fd, (struct sockaddr *) &sin, sizeof sin);
    if (retval < 0) {
        if (errno == EINPROGRESS) {
            return new_tcp_vconn(name, fd, EAGAIN, &sin, vconnp);
        } else {
            int error = errno;
            VLOG_ERR("%s: connect: %s", name, strerror(error));
            close(fd);
            return error;
        }
    } else {
        return new_tcp_vconn(name, fd, 0, &sin, vconnp);
    }
}

struct vconn_class tcp_vconn_class = {
    "tcp",                      /* name */
    tcp_open,                   /* open */
    NULL,                       /* close */
    NULL,                       /* connect */
    NULL,                       /* recv */
    NULL,                       /* send */
    NULL,                       /* wait */
};

/* Passive TCP. */

static int ptcp_accept(int fd, const struct sockaddr *sa, size_t sa_len,
                       struct vconn **vconnp);

static int
ptcp_open(const char *name, char *suffix, struct pvconn **pvconnp)
{
    struct sockaddr_in sin;
    int retval;
    int fd;
    unsigned int yes  = 1;

    fd = socket(AF_INET, SOCK_STREAM, 0);
    if (fd < 0) {
        VLOG_ERR("%s: socket: %s", name, strerror(errno));
        return errno;
    }

    if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof yes) < 0) {
        VLOG_ERR("%s: setsockopt(SO_REUSEADDR): %s", name, strerror(errno));
        return errno;
    }

    memset(&sin, 0, sizeof sin);
    sin.sin_family = AF_INET;
    sin.sin_addr.s_addr = htonl(INADDR_ANY);
    sin.sin_port = htons(atoi(suffix) ? atoi(suffix) : OFP_TCP_PORT);
    retval = bind(fd, (struct sockaddr *) &sin, sizeof sin);
    if (retval < 0) {
        int error = errno;
        VLOG_ERR("%s: bind: %s", name, strerror(error));
        close(fd);
        return error;
    }

    return new_pstream_pvconn("ptcp", fd, ptcp_accept, pvconnp);
}

static int
ptcp_accept(int fd, const struct sockaddr *sa, size_t sa_len,
            struct vconn **vconnp)
{
    const struct sockaddr_in *sin = (const struct sockaddr_in *) sa;
    char name[128];

    if (sa_len == sizeof(struct sockaddr_in) && sin->sin_family == AF_INET) {
        sprintf(name, "tcp:"IP_FMT, IP_ARGS(&sin->sin_addr));
        if (sin->sin_port != htons(OFP_TCP_PORT)) {
            sprintf(strchr(name, '\0'), ":%"PRIu16, ntohs(sin->sin_port));
        }
    } else {
        strcpy(name, "tcp");
    }
    return new_tcp_vconn(name, fd, 0, sin, vconnp);
}

struct pvconn_class ptcp_pvconn_class = {
    "ptcp",
    ptcp_open,
};