/src/libssh/src/config_parser.c

Source (jump to first uncovered line)
/*
 * 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"
#include "libssh/misc.h"

/* Returns the original string after skipping the leading whitespace
 * until finding LF.
 * This is useful in case we need to get the rest of the line (for example
 * external command).
 */
char *ssh_config_get_cmd(char **str)
{
    register char *c = NULL;
    char *r = NULL;

    /* Ignore leading spaces */
    for (c = *str; *c; c++) {
        if (! isblank(*c)) {
            break;
        }
    }

    for (r = c; *c; c++) {
        if (*c == '\n') {
            *c = '\0';
            goto out;
        }
    }

out:
    *str = c + 1;

    return r;
}

/* Returns the next token delimited by whitespace or equal sign (=)
 * respecting the quotes creating separate token (including whitespaces).
 */
char *ssh_config_get_token(char **str)
{
    register char *c = NULL;
    bool had_equal = false;
    char *r = NULL;

    /* Ignore leading spaces */
    for (c = *str; *c; c++) {
        if (! isblank(*c)) {
            break;
        }
    }

    /* If we start with quote, return the whole quoted block */
    if (*c == '\"') {
        for (r = ++c; *c; c++) {
            if (*c == '\"' || *c == '\n') {
                if (*c == '\"' && r != c && *(c - 1) == '\\') {
                    /* Escaped quote: Move the remaining one char left */
                    int remaining_len = strlen(c);
                    memmove(c - 1, c, remaining_len);
                    c[remaining_len - 1] = '\0';
                    continue;
                }
                *c = '\0';
                c++;
                break;
            }
            /* XXX Unmatched quotes extend to the end of line */
        }
    } else {
        /* Otherwise terminate on space, equal or newline */
        for (r = c; *c; c++) {
            if (*c == '\0') {
                goto out;
            } else if (isblank(*c) || *c == '=' || *c == '\n') {
                had_equal = (*c == '=');
                *c = '\0';
                c++;
                break;
            }
        }
    }

    /* Skip any other remaining whitespace */
    while (isblank(*c) || *c == '\n' || (!had_equal && *c == '=')) {
        if (*c == '=') {
            had_equal = true;
        }
        c++;
    }
out:
    *str = c;
    return r;
}

long ssh_config_get_long(char **str, long notfound)
{
    char *p = NULL, *endp = NULL;
    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 = NULL;

    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 = NULL;

    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,
                         bool ignore_port)
{
    char *endp = NULL;
    long port_n;
    int rc;

    /* Sanitize inputs */
    if (username != NULL) {
        *username = NULL;
    }
    if (hostname != NULL) {
        *hostname = NULL;
    }
    if (port != NULL) {
        *port = NULL;
    }

    /* Username part (optional) */
    endp = strrchr(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;
            }
            rc = ssh_check_username_syntax(*username);
            if (rc != SSH_OK) {
                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 if (!ignore_port) {
        /* Hostnames or aliases expand to the last colon (if port is requested)
         * or to the end */
        endp = strrchr(tok, ':');
        if (endp == NULL) {
            endp = strchr(tok, '\0');
        }
    } else {
        /* If no port is requested, expand to the end of line
         * (to accommodate the IPv6 addresses) */
        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;
        }
        /* if not an ip, check syntax */
        rc = ssh_is_ipaddr(*hostname);
        if (rc == 0) {
            rc = ssh_check_hostname_syntax(*hostname);
            if (rc != SSH_OK) {
                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_TRACE, "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;
}

Coverage Report

Created: 2025-08-29 06:06

Line	Count	Source (jump to first uncovered line)
1		/*
2		* config_parser.c - Common configuration file parser functions
3		*
4		* This file is part of the SSH Library
5		*
6		* Copyright (c) 2009-2013 by Andreas Schneider <asn@cryptomilk.org>
7		*
8		* The SSH Library is free software; you can redistribute it and/or modify
9		* it under the terms of the GNU Lesser General Public License as published by
10		* the Free Software Foundation; either version 2.1 of the License, or (at your
11		* option) any later version.
12		*
13		* The SSH Library is distributed in the hope that it will be useful, but
14		* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
15		* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
16		* License for more details.
17		*
18		* You should have received a copy of the GNU Lesser General Public License
19		* along with the SSH Library; see the file COPYING. If not, write to
20		* the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
21		* MA 02111-1307, USA.
22		*/
23
24		#include "config.h"
25
26		#include <ctype.h>
27		#include <stdio.h>
28		#include <string.h>
29		#include <stdlib.h>
30
31		#include "libssh/config_parser.h"
32		#include "libssh/priv.h"
33		#include "libssh/misc.h"
34
35		/* Returns the original string after skipping the leading whitespace
36		* until finding LF.
37		* This is useful in case we need to get the rest of the line (for example
38		* external command).
39		*/
40		char ssh_config_get_cmd(char *str)
41	0	{
42	0	register char *c = NULL;
43	0	char *r = NULL;
44
45		/* Ignore leading spaces */
46	0	for (c = str; c; c++) {
47	0	if (! isblank(*c)) {
48	0	break;
49	0	}
50	0	}
51
52	0	for (r = c; *c; c++) {
53	0	if (*c == '\n') {
54	0	*c = '\0';
55	0	goto out;
56	0	}
57	0	}
58
59	0	out:
60	0	*str = c + 1;
61
62	0	return r;
63	0	}
64
65		/* Returns the next token delimited by whitespace or equal sign (=)
66		* respecting the quotes creating separate token (including whitespaces).
67		*/
68		char ssh_config_get_token(char *str)
69	0	{
70	0	register char *c = NULL;
71	0	bool had_equal = false;
72	0	char *r = NULL;
73
74		/* Ignore leading spaces */
75	0	for (c = str; c; c++) {
76	0	if (! isblank(*c)) {
77	0	break;
78	0	}
79	0	}
80
81		/* If we start with quote, return the whole quoted block */
82	0	if (*c == '\"') {
83	0	for (r = ++c; *c; c++) {
84	0	if (c == '\"' \|\| c == '\n') {
85	0	if (c == '\"' && r != c && (c - 1) == '\\') {
86		/* Escaped quote: Move the remaining one char left */
87	0	int remaining_len = strlen(c);
88	0	memmove(c - 1, c, remaining_len);
89	0	c[remaining_len - 1] = '\0';
90	0	continue;
91	0	}
92	0	*c = '\0';
93	0	c++;
94	0	break;
95	0	}
96		/* XXX Unmatched quotes extend to the end of line */
97	0	}
98	0	} else {
99		/* Otherwise terminate on space, equal or newline */
100	0	for (r = c; *c; c++) {
101	0	if (*c == '\0') {
102	0	goto out;
103	0	} else if (isblank(c) \|\| c == '=' \|\| *c == '\n') {
104	0	had_equal = (*c == '=');
105	0	*c = '\0';
106	0	c++;
107	0	break;
108	0	}
109	0	}
110	0	}
111
112		/* Skip any other remaining whitespace */
113	0	while (isblank(c) \|\| c == '\n' \|\| (!had_equal && *c == '=')) {
114	0	if (*c == '=') {
115	0	had_equal = true;
116	0	}
117	0	c++;
118	0	}
119	0	out:
120	0	*str = c;
121	0	return r;
122	0	}
123
124		long ssh_config_get_long(char **str, long notfound)
125	0	{
126	0	char p = NULL, endp = NULL;
127	0	long i;
128
129	0	p = ssh_config_get_token(str);
130	0	if (p && *p) {
131	0	i = strtol(p, &endp, 10);
132	0	if (p == endp) {
133	0	return notfound;
134	0	}
135	0	return i;
136	0	}
137
138	0	return notfound;
139	0	}
140
141		const char ssh_config_get_str_tok(char str, const char def)
142	0	{
143	0	char *p = NULL;
144
145	0	p = ssh_config_get_token(str);
146	0	if (p && *p) {
147	0	return p;
148	0	}
149
150	0	return def;
151	0	}
152
153		int ssh_config_get_yesno(char **str, int notfound)
154	0	{
155	0	const char *p = NULL;
156
157	0	p = ssh_config_get_str_tok(str, NULL);
158	0	if (p == NULL) {
159	0	return notfound;
160	0	}
161
162	0	if (strncasecmp(p, "yes", 3) == 0) {
163	0	return 1;
164	0	} else if (strncasecmp(p, "no", 2) == 0) {
165	0	return 0;
166	0	}
167
168	0	return notfound;
169	0	}
170
171		int ssh_config_parse_uri(const char *tok,
172		char **username,
173		char **hostname,
174		char **port,
175		bool ignore_port)
176	0	{
177	0	char *endp = NULL;
178	0	long port_n;
179	0	int rc;
180
181		/* Sanitize inputs */
182	0	if (username != NULL) {
183	0	*username = NULL;
184	0	}
185	0	if (hostname != NULL) {
186	0	*hostname = NULL;
187	0	}
188	0	if (port != NULL) {
189	0	*port = NULL;
190	0	}
191
192		/* Username part (optional) */
193	0	endp = strrchr(tok, '@');
194	0	if (endp != NULL) {
195		/* Zero-length username is not valid */
196	0	if (tok == endp) {
197	0	goto error;
198	0	}
199	0	if (username != NULL) {
200	0	*username = strndup(tok, endp - tok);
201	0	if (*username == NULL) {
202	0	goto error;
203	0	}
204	0	rc = ssh_check_username_syntax(*username);
205	0	if (rc != SSH_OK) {
206	0	goto error;
207	0	}
208	0	}
209	0	tok = endp + 1;
210		/* If there is second @ character, this does not look like our URI */
211	0	endp = strchr(tok, '@');
212	0	if (endp != NULL) {
213	0	goto error;
214	0	}
215	0	}
216
217		/* Hostname */
218	0	if (*tok == '[') {
219		/* IPv6 address is enclosed with square brackets */
220	0	tok++;
221	0	endp = strchr(tok, ']');
222	0	if (endp == NULL) {
223	0	goto error;
224	0	}
225	0	} else if (!ignore_port) {
226		/* Hostnames or aliases expand to the last colon (if port is requested)
227		* or to the end */
228	0	endp = strrchr(tok, ':');
229	0	if (endp == NULL) {
230	0	endp = strchr(tok, '\0');
231	0	}
232	0	} else {
233		/* If no port is requested, expand to the end of line
234		* (to accommodate the IPv6 addresses) */
235	0	endp = strchr(tok, '\0');
236	0	}
237	0	if (tok == endp) {
238		/* Zero-length hostnames are not valid */
239	0	goto error;
240	0	}
241	0	if (hostname != NULL) {
242	0	*hostname = strndup(tok, endp - tok);
243	0	if (*hostname == NULL) {
244	0	goto error;
245	0	}
246		/* if not an ip, check syntax */
247	0	rc = ssh_is_ipaddr(*hostname);
248	0	if (rc == 0) {
249	0	rc = ssh_check_hostname_syntax(*hostname);
250	0	if (rc != SSH_OK) {
251	0	goto error;
252	0	}
253	0	}
254	0	}
255		/* Skip also the closing bracket */
256	0	if (*endp == ']') {
257	0	endp++;
258	0	}
259
260		/* Port (optional) */
261	0	if (*endp != '\0') {
262	0	char *port_end = NULL;
263
264		/* Verify the port is valid positive number */
265	0	port_n = strtol(endp + 1, &port_end, 10);
266	0	if (port_n < 1 \|\| *port_end != '\0') {
267	0	SSH_LOG(SSH_LOG_TRACE, "Failed to parse port number."
268	0	" The value '%ld' is invalid or there are some"
269	0	" trailing characters: '%s'", port_n, port_end);
270	0	goto error;
271	0	}
272	0	if (port != NULL) {
273	0	*port = strdup(endp + 1);
274	0	if (*port == NULL) {
275	0	goto error;
276	0	}
277	0	}
278	0	}
279
280	0	return SSH_OK;
281
282	0	error:
283	0	if (username != NULL) {
284	0	SAFE_FREE(*username);
285	0	}
286	0	if (hostname != NULL) {
287	0	SAFE_FREE(*hostname);
288	0	}
289	0	if (port != NULL) {
290	0	SAFE_FREE(*port);
291	0	}
292	0	return SSH_ERROR;
293	0	}