/*

 * config_parser.c - Common configuration file parser functions

 *

 * This file is part of the SSH Library

 *

 * Copyright (c) 2009-2013    by Andreas Schneider <asn@cryptomilk.org>

 *

 * The SSH Library is free software; you can redistribute it and/or modify

 * it under the terms of the GNU Lesser General Public License as published by

 * the Free Software Foundation; either version 2.1 of the License, or (at your

 * option) any later version.

 *

 * The SSH Library 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 Lesser General Public

 * License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public License

 * along with the SSH Library; see the file COPYING.  If not, write to

 * the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,

 * MA 02111-1307, USA.

 */

#include "config.h"

#include <ctype.h>

#include <stdio.h>

#include <string.h>

#include <stdlib.h>

#include "libssh/config_parser.h"

#include "libssh/priv.h"

char *ssh_config_get_cmd(char **str)

{

    register char *c;

    char *r;

    /* Ignore leading spaces */

    for (c = *str; *c; c++) {

        if (! isblank(*c)) {

            break;

        }

    }

    if (*c == '\"') {

        for (r = ++c; *c; c++) {

            if (*c == '\"') {

                *c = '\0';

                goto out;

            }

        }

    }

    for (r = c; *c; c++) {

        if (*c == '\n') {

            *c = '\0';

            goto out;

        }

    }

out:

    *str = c + 1;

    return r;

}

char *ssh_config_get_token(char **str)

{

    register char *c;

    char *r;

    c = ssh_config_get_cmd(str);

    for (r = c; *c; c++) {

        if (isblank(*c) || *c == '=') {

            *c = '\0';

            goto out;

        }

    }

out:

    *str = c + 1;

    return r;

}

long ssh_config_get_long(char **str, long notfound)

{

    char *p, *endp;

    long i;

    p = ssh_config_get_token(str);

    if (p && *p) {

        i = strtol(p, &endp, 10);

        if (p == endp) {

            return notfound;

        }

        return i;

    }

    return notfound;

}

const char *ssh_config_get_str_tok(char **str, const char *def)

{

    char *p;

    p = ssh_config_get_token(str);

    if (p && *p) {

        return p;

    }

    return def;

}

int ssh_config_get_yesno(char **str, int notfound)

{

    const char *p;

    p = ssh_config_get_str_tok(str, NULL);

    if (p == NULL) {

        return notfound;

    }

    if (strncasecmp(p, "yes", 3) == 0) {

        return 1;

    } else if (strncasecmp(p, "no", 2) == 0) {

        return 0;

    }

    return notfound;

}

int ssh_config_parse_uri(const char *tok,

        char **username,

        char **hostname,

        char **port)

{

    char *endp = NULL;

    long port_n;

    /* Sanitize inputs */

    if (username != NULL) {

        *username = NULL;

    }

    if (hostname != NULL) {

        *hostname = NULL;

    }

    if (port != NULL) {

        *port = NULL;

    }

    /* Username part (optional) */

    endp = strchr(tok, '@');

    if (endp != NULL) {

        /* Zero-length username is not valid */

        if (tok == endp) {

            goto error;

        }

        if (username != NULL) {

            *username = strndup(tok, endp - tok);

            if (*username == NULL) {

                goto error;

            }

        }

        tok = endp + 1;

        /* If there is second @ character, this does not look like our URI */

        endp = strchr(tok, '@');

        if (endp != NULL) {

            goto error;

        }

    }

    /* Hostname */

    if (*tok == '[') {

        /* IPv6 address is enclosed with square brackets */

        tok++;

        endp = strchr(tok, ']');

        if (endp == NULL) {

            goto error;

        }

    } else {

        /* Hostnames or aliases expand to the last colon or to the end */

        endp = strrchr(tok, ':');

        if (endp == NULL) {

            endp = strchr(tok, '\0');

        }

    }

    if (tok == endp) {

        /* Zero-length hostnames are not valid */

        goto error;

    }

    if (hostname != NULL) {

        *hostname = strndup(tok, endp - tok);

        if (*hostname == NULL) {

            goto error;

        }

    }

    /* Skip also the closing bracket */

    if (*endp == ']') {

        endp++;

    }

    /* Port (optional) */

    if (*endp != '\0') {

        char *port_end = NULL;

        /* Verify the port is valid positive number */

        port_n = strtol(endp + 1, &port_end, 10);

        if (port_n < 1 || *port_end != '\0') {

            SSH_LOG(SSH_LOG_WARN, "Failed to parse port number."

                    " The value '%ld' is invalid or there are some"

                    " trailing characters: '%s'", port_n, port_end);

            goto error;

        }

        if (port != NULL) {

            *port = strdup(endp + 1);

            if (*port == NULL) {

                goto error;

            }

        }

    }

    return SSH_OK;

error:

    if (username != NULL) {

        SAFE_FREE(*username);

    }

    if (hostname != NULL) {

        SAFE_FREE(*hostname);

    }

    if (port != NULL) {

        SAFE_FREE(*port);

    }

    return SSH_ERROR;

}