xref: /freebsd/contrib/openpam/lib/libpam/openpam_readline.c (revision f7e6344d4a3b7072f8b8a1dec8f483a5a3ca50eb)
1*f7e6344dSDag-Erling Smørgrav /*-
2*f7e6344dSDag-Erling Smørgrav  * Copyright (c) 2003 Networks Associates Technology, Inc.
3*f7e6344dSDag-Erling Smørgrav  * Copyright (c) 2004-2011 Dag-Erling Smørgrav
4*f7e6344dSDag-Erling Smørgrav  * All rights reserved.
5*f7e6344dSDag-Erling Smørgrav  *
6*f7e6344dSDag-Erling Smørgrav  * This software was developed for the FreeBSD Project by ThinkSec AS and
7*f7e6344dSDag-Erling Smørgrav  * Network Associates Laboratories, the Security Research Division of
8*f7e6344dSDag-Erling Smørgrav  * Network Associates, Inc.  under DARPA/SPAWAR contract N66001-01-C-8035
9*f7e6344dSDag-Erling Smørgrav  * ("CBOSS"), as part of the DARPA CHATS research program.
10*f7e6344dSDag-Erling Smørgrav  *
11*f7e6344dSDag-Erling Smørgrav  * Redistribution and use in source and binary forms, with or without
12*f7e6344dSDag-Erling Smørgrav  * modification, are permitted provided that the following conditions
13*f7e6344dSDag-Erling Smørgrav  * are met:
14*f7e6344dSDag-Erling Smørgrav  * 1. Redistributions of source code must retain the above copyright
15*f7e6344dSDag-Erling Smørgrav  *    notice, this list of conditions and the following disclaimer.
16*f7e6344dSDag-Erling Smørgrav  * 2. Redistributions in binary form must reproduce the above copyright
17*f7e6344dSDag-Erling Smørgrav  *    notice, this list of conditions and the following disclaimer in the
18*f7e6344dSDag-Erling Smørgrav  *    documentation and/or other materials provided with the distribution.
19*f7e6344dSDag-Erling Smørgrav  * 3. The name of the author may not be used to endorse or promote
20*f7e6344dSDag-Erling Smørgrav  *    products derived from this software without specific prior written
21*f7e6344dSDag-Erling Smørgrav  *    permission.
22*f7e6344dSDag-Erling Smørgrav  *
23*f7e6344dSDag-Erling Smørgrav  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
24*f7e6344dSDag-Erling Smørgrav  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25*f7e6344dSDag-Erling Smørgrav  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26*f7e6344dSDag-Erling Smørgrav  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
27*f7e6344dSDag-Erling Smørgrav  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28*f7e6344dSDag-Erling Smørgrav  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29*f7e6344dSDag-Erling Smørgrav  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30*f7e6344dSDag-Erling Smørgrav  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31*f7e6344dSDag-Erling Smørgrav  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32*f7e6344dSDag-Erling Smørgrav  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33*f7e6344dSDag-Erling Smørgrav  * SUCH DAMAGE.
34*f7e6344dSDag-Erling Smørgrav  *
35*f7e6344dSDag-Erling Smørgrav  * $Id: openpam_readline.c 596 2012-04-14 14:52:40Z des $
36*f7e6344dSDag-Erling Smørgrav  */
37*f7e6344dSDag-Erling Smørgrav 
38*f7e6344dSDag-Erling Smørgrav #ifdef HAVE_CONFIG_H
39*f7e6344dSDag-Erling Smørgrav # include "config.h"
40*f7e6344dSDag-Erling Smørgrav #endif
41*f7e6344dSDag-Erling Smørgrav 
42*f7e6344dSDag-Erling Smørgrav #include <ctype.h>
43*f7e6344dSDag-Erling Smørgrav #include <stdio.h>
44*f7e6344dSDag-Erling Smørgrav #include <stdlib.h>
45*f7e6344dSDag-Erling Smørgrav 
46*f7e6344dSDag-Erling Smørgrav #include <security/pam_appl.h>
47*f7e6344dSDag-Erling Smørgrav 
48*f7e6344dSDag-Erling Smørgrav #include "openpam_impl.h"
49*f7e6344dSDag-Erling Smørgrav 
50*f7e6344dSDag-Erling Smørgrav #define MIN_LINE_LENGTH 128
51*f7e6344dSDag-Erling Smørgrav 
52*f7e6344dSDag-Erling Smørgrav /*
53*f7e6344dSDag-Erling Smørgrav  * OpenPAM extension
54*f7e6344dSDag-Erling Smørgrav  *
55*f7e6344dSDag-Erling Smørgrav  * Read a line from a file.
56*f7e6344dSDag-Erling Smørgrav  */
57*f7e6344dSDag-Erling Smørgrav 
58*f7e6344dSDag-Erling Smørgrav char *
59*f7e6344dSDag-Erling Smørgrav openpam_readline(FILE *f, int *lineno, size_t *lenp)
60*f7e6344dSDag-Erling Smørgrav {
61*f7e6344dSDag-Erling Smørgrav 	char *line;
62*f7e6344dSDag-Erling Smørgrav 	size_t len, size;
63*f7e6344dSDag-Erling Smørgrav 	int ch;
64*f7e6344dSDag-Erling Smørgrav 
65*f7e6344dSDag-Erling Smørgrav 	line = NULL;
66*f7e6344dSDag-Erling Smørgrav 	if (openpam_straddch(&line, &size, &len, 0) != 0)
67*f7e6344dSDag-Erling Smørgrav 		return (NULL);
68*f7e6344dSDag-Erling Smørgrav 	for (;;) {
69*f7e6344dSDag-Erling Smørgrav 		ch = fgetc(f);
70*f7e6344dSDag-Erling Smørgrav 		/* strip comment */
71*f7e6344dSDag-Erling Smørgrav 		if (ch == '#') {
72*f7e6344dSDag-Erling Smørgrav 			do {
73*f7e6344dSDag-Erling Smørgrav 				ch = fgetc(f);
74*f7e6344dSDag-Erling Smørgrav 			} while (ch != EOF && ch != '\n');
75*f7e6344dSDag-Erling Smørgrav 		}
76*f7e6344dSDag-Erling Smørgrav 		/* eof */
77*f7e6344dSDag-Erling Smørgrav 		if (ch == EOF) {
78*f7e6344dSDag-Erling Smørgrav 			/* done */
79*f7e6344dSDag-Erling Smørgrav 			break;
80*f7e6344dSDag-Erling Smørgrav 		}
81*f7e6344dSDag-Erling Smørgrav 		/* eol */
82*f7e6344dSDag-Erling Smørgrav 		if (ch == '\n') {
83*f7e6344dSDag-Erling Smørgrav 			if (lineno != NULL)
84*f7e6344dSDag-Erling Smørgrav 				++*lineno;
85*f7e6344dSDag-Erling Smørgrav 			/* skip blank lines */
86*f7e6344dSDag-Erling Smørgrav 			if (len == 0)
87*f7e6344dSDag-Erling Smørgrav 				continue;
88*f7e6344dSDag-Erling Smørgrav 			/* continuation */
89*f7e6344dSDag-Erling Smørgrav 			if (line[len - 1] == '\\') {
90*f7e6344dSDag-Erling Smørgrav 				line[--len] = '\0';
91*f7e6344dSDag-Erling Smørgrav 				continue;
92*f7e6344dSDag-Erling Smørgrav 			}
93*f7e6344dSDag-Erling Smørgrav 			/* done */
94*f7e6344dSDag-Erling Smørgrav 			break;
95*f7e6344dSDag-Erling Smørgrav 		}
96*f7e6344dSDag-Erling Smørgrav 		/* anything else */
97*f7e6344dSDag-Erling Smørgrav 		if (openpam_straddch(&line, &size, &len, ch) != 0)
98*f7e6344dSDag-Erling Smørgrav 			goto fail;
99*f7e6344dSDag-Erling Smørgrav 	}
100*f7e6344dSDag-Erling Smørgrav 	if (len == 0)
101*f7e6344dSDag-Erling Smørgrav 		goto fail;
102*f7e6344dSDag-Erling Smørgrav 	if (lenp != NULL)
103*f7e6344dSDag-Erling Smørgrav 		*lenp = len;
104*f7e6344dSDag-Erling Smørgrav 	openpam_log(PAM_LOG_LIBDEBUG, "returning '%s'", line);
105*f7e6344dSDag-Erling Smørgrav 	return (line);
106*f7e6344dSDag-Erling Smørgrav fail:
107*f7e6344dSDag-Erling Smørgrav 	FREE(line);
108*f7e6344dSDag-Erling Smørgrav 	return (NULL);
109*f7e6344dSDag-Erling Smørgrav }
110*f7e6344dSDag-Erling Smørgrav 
111*f7e6344dSDag-Erling Smørgrav /**
112*f7e6344dSDag-Erling Smørgrav  * DEPRECATED openpam_readlinev
113*f7e6344dSDag-Erling Smørgrav  *
114*f7e6344dSDag-Erling Smørgrav  * The =openpam_readline function reads a line from a file, and returns it
115*f7e6344dSDag-Erling Smørgrav  * in a NUL-terminated buffer allocated with =!malloc.
116*f7e6344dSDag-Erling Smørgrav  *
117*f7e6344dSDag-Erling Smørgrav  * The =openpam_readline function performs a certain amount of processing
118*f7e6344dSDag-Erling Smørgrav  * on the data it reads:
119*f7e6344dSDag-Erling Smørgrav  *
120*f7e6344dSDag-Erling Smørgrav  *  - Comments (introduced by a hash sign) are stripped.
121*f7e6344dSDag-Erling Smørgrav  *
122*f7e6344dSDag-Erling Smørgrav  *  - Blank lines are ignored.
123*f7e6344dSDag-Erling Smørgrav  *
124*f7e6344dSDag-Erling Smørgrav  *  - If a line ends in a backslash, the backslash is stripped and the
125*f7e6344dSDag-Erling Smørgrav  *    next line is appended.
126*f7e6344dSDag-Erling Smørgrav  *
127*f7e6344dSDag-Erling Smørgrav  * If =lineno is not =NULL, the integer variable it points to is
128*f7e6344dSDag-Erling Smørgrav  * incremented every time a newline character is read.
129*f7e6344dSDag-Erling Smørgrav  *
130*f7e6344dSDag-Erling Smørgrav  * If =lenp is not =NULL, the length of the line (not including the
131*f7e6344dSDag-Erling Smørgrav  * terminating NUL character) is stored in the variable it points to.
132*f7e6344dSDag-Erling Smørgrav  *
133*f7e6344dSDag-Erling Smørgrav  * The caller is responsible for releasing the returned buffer by passing
134*f7e6344dSDag-Erling Smørgrav  * it to =!free.
135*f7e6344dSDag-Erling Smørgrav  *
136*f7e6344dSDag-Erling Smørgrav  * >openpam_readlinev
137*f7e6344dSDag-Erling Smørgrav  * >openpam_readword
138*f7e6344dSDag-Erling Smørgrav  */
139