xref: /freebsd/contrib/openbsm/libbsm/bsm_flags.c (revision dd41de95a84d979615a2ef11df6850622bf6184e)
1 /*-
2  * Copyright (c) 2004 Apple Inc.
3  * Copyright (c) 2006 Robert N. M. Watson
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1.  Redistributions of source code must retain the above copyright
10  *     notice, this list of conditions and the following disclaimer.
11  * 2.  Redistributions in binary form must reproduce the above copyright
12  *     notice, this list of conditions and the following disclaimer in the
13  *     documentation and/or other materials provided with the distribution.
14  * 3.  Neither the name of Apple Inc. ("Apple") nor the names of
15  *     its contributors may be used to endorse or promote products derived
16  *     from this software without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR
22  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
26  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
27  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28  * POSSIBILITY OF SUCH DAMAGE.
29  */
30 
31 #include <config/config.h>
32 
33 #include <bsm/libbsm.h>
34 
35 #include <errno.h>
36 #include <stdio.h>
37 #include <string.h>
38 
39 #ifndef HAVE_STRLCPY
40 #include <compat/strlcpy.h>
41 #endif
42 
43 static const char	*flagdelim = ",";
44 
45 /*
46  * Convert the character representation of audit values into the au_mask_t
47  * field.
48  */
49 int
50 getauditflagsbin(char *auditstr, au_mask_t *masks)
51 {
52 	char class_ent_name[AU_CLASS_NAME_MAX];
53 	char class_ent_desc[AU_CLASS_DESC_MAX];
54 	struct au_class_ent c;
55 	char *tok;
56 	char sel, sub;
57 	char *last;
58 
59 	bzero(&c, sizeof(c));
60 	bzero(class_ent_name, sizeof(class_ent_name));
61 	bzero(class_ent_desc, sizeof(class_ent_desc));
62 	c.ac_name = class_ent_name;
63 	c.ac_desc = class_ent_desc;
64 
65 	masks->am_success = 0;
66 	masks->am_failure = 0;
67 
68 	tok = strtok_r(auditstr, flagdelim, &last);
69 	while (tok != NULL) {
70 		/* Check for the events that should not be audited. */
71 		if (tok[0] == '^') {
72 			sub = 1;
73 			tok++;
74 		} else
75 			sub = 0;
76 
77 		/* Check for the events to be audited for success. */
78 		if (tok[0] == '+') {
79 			sel = AU_PRS_SUCCESS;
80 			tok++;
81 		} else if (tok[0] == '-') {
82 			sel = AU_PRS_FAILURE;
83 			tok++;
84 		} else
85 			sel = AU_PRS_BOTH;
86 
87 		if ((getauclassnam_r(&c, tok)) != NULL) {
88 			if (sub)
89 				SUB_FROM_MASK(masks, c.ac_class, sel);
90 			else
91 				ADD_TO_MASK(masks, c.ac_class, sel);
92 		} else {
93 			errno = EINVAL;
94 			return (-1);
95 		}
96 
97 		/* Get the next class. */
98 		tok = strtok_r(NULL, flagdelim, &last);
99 	}
100 	return (0);
101 }
102 
103 /*
104  * Convert the au_mask_t fields into a string value.  If verbose is non-zero
105  * the long flag names are used else the short (2-character)flag names are
106  * used.
107  *
108  * XXXRW: If bits are specified that are not matched by any class, they are
109  * omitted rather than rejected with EINVAL.
110  *
111  * XXXRW: This is not thread-safe as it relies on atomicity between
112  * setauclass() and sequential calls to getauclassent().  This could be
113  * fixed by iterating through the bitmask fields rather than iterating
114  * through the classes.
115  */
116 int
117 getauditflagschar(char *auditstr, au_mask_t *masks, int verbose)
118 {
119 	char class_ent_name[AU_CLASS_NAME_MAX];
120 	char class_ent_desc[AU_CLASS_DESC_MAX];
121 	struct au_class_ent c;
122 	char *strptr = auditstr;
123 	u_char sel;
124 
125 	bzero(&c, sizeof(c));
126 	bzero(class_ent_name, sizeof(class_ent_name));
127 	bzero(class_ent_desc, sizeof(class_ent_desc));
128 	c.ac_name = class_ent_name;
129 	c.ac_desc = class_ent_desc;
130 
131 	/*
132 	 * Enumerate the class entries, check if each is selected in either
133 	 * the success or failure masks.
134 	 */
135 	setauclass();
136 	while ((getauclassent_r(&c)) != NULL) {
137 		sel = 0;
138 
139 		/* Dont do anything for class = no. */
140 		if (c.ac_class == 0)
141 			continue;
142 
143 		sel |= ((c.ac_class & masks->am_success) == c.ac_class) ?
144 		    AU_PRS_SUCCESS : 0;
145 		sel |= ((c.ac_class & masks->am_failure) == c.ac_class) ?
146 		    AU_PRS_FAILURE : 0;
147 
148 		/*
149 		 * No prefix should be attached if both success and failure
150 		 * are selected.
151 		 */
152 		if ((sel & AU_PRS_BOTH) == 0) {
153 			if ((sel & AU_PRS_SUCCESS) != 0) {
154 				*strptr = '+';
155 				strptr = strptr + 1;
156 			} else if ((sel & AU_PRS_FAILURE) != 0) {
157 				*strptr = '-';
158 				strptr = strptr + 1;
159 			}
160 		}
161 
162 		if (sel != 0) {
163 			if (verbose) {
164 				strlcpy(strptr, c.ac_desc, AU_CLASS_DESC_MAX);
165 				strptr += strlen(c.ac_desc);
166 			} else {
167 				strlcpy(strptr, c.ac_name, AU_CLASS_NAME_MAX);
168 				strptr += strlen(c.ac_name);
169 			}
170 			*strptr = ','; /* delimiter */
171 			strptr = strptr + 1;
172 		}
173 	}
174 
175 	/* Overwrite the last delimiter with the string terminator. */
176 	if (strptr != auditstr)
177 		*(strptr-1) = '\0';
178 
179 	return (0);
180 }
181