1 /* $NetBSD: sel.c,v 1.1.1.2 2014/04/24 12:45:42 pettai Exp $ */
2
3 /*
4 * Copyright (c) 2008 Kungliga Tekniska Högskolan
5 * (Royal Institute of Technology, Stockholm, Sweden).
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 *
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * 3. Neither the name of the Institute nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36 #include "hx_locl.h"
37
38 struct hx_expr *
_hx509_make_expr(enum hx_expr_op op,void * arg1,void * arg2)39 _hx509_make_expr(enum hx_expr_op op, void *arg1, void *arg2)
40 {
41 struct hx_expr *expr;
42
43 expr = malloc(sizeof(*expr));
44 if (expr == NULL)
45 return NULL;
46 expr->op = op;
47 expr->arg1 = arg1;
48 expr->arg2 = arg2;
49
50 return expr;
51 }
52
53 static const char *
eval_word(hx509_context context,hx509_env env,struct hx_expr * word)54 eval_word(hx509_context context, hx509_env env, struct hx_expr *word)
55 {
56 switch (word->op) {
57 case expr_STRING:
58 return word->arg1;
59 case expr_VAR:
60 if (word->arg2 == NULL)
61 return hx509_env_find(context, env, word->arg1);
62
63 env = hx509_env_find_binding(context, env, word->arg1);
64 if (env == NULL)
65 return NULL;
66
67 return eval_word(context, env, word->arg2);
68 default:
69 return NULL;
70 }
71 }
72
73 static hx509_env
find_variable(hx509_context context,hx509_env env,struct hx_expr * word)74 find_variable(hx509_context context, hx509_env env, struct hx_expr *word)
75 {
76 assert(word->op == expr_VAR);
77
78 if (word->arg2 == NULL)
79 return hx509_env_find_binding(context, env, word->arg1);
80
81 env = hx509_env_find_binding(context, env, word->arg1);
82 if (env == NULL)
83 return NULL;
84 return find_variable(context, env, word->arg2);
85 }
86
87 static int
eval_comp(hx509_context context,hx509_env env,struct hx_expr * expr)88 eval_comp(hx509_context context, hx509_env env, struct hx_expr *expr)
89 {
90 switch (expr->op) {
91 case comp_NE:
92 case comp_EQ:
93 case comp_TAILEQ: {
94 const char *s1, *s2;
95 int ret;
96
97 s1 = eval_word(context, env, expr->arg1);
98 s2 = eval_word(context, env, expr->arg2);
99
100 if (s1 == NULL || s2 == NULL)
101 return FALSE;
102
103 if (expr->op == comp_TAILEQ) {
104 size_t len1 = strlen(s1);
105 size_t len2 = strlen(s2);
106
107 if (len1 < len2)
108 return 0;
109 ret = strcmp(s1 + (len1 - len2), s2) == 0;
110 } else {
111 ret = strcmp(s1, s2) == 0;
112 if (expr->op == comp_NE)
113 ret = !ret;
114 }
115 return ret;
116 }
117 case comp_IN: {
118 struct hx_expr *subexpr;
119 const char *w, *s1;
120
121 w = eval_word(context, env, expr->arg1);
122
123 subexpr = expr->arg2;
124
125 if (subexpr->op == expr_WORDS) {
126 while (subexpr) {
127 s1 = eval_word(context, env, subexpr->arg1);
128 if (strcmp(w, s1) == 0)
129 return TRUE;
130 subexpr = subexpr->arg2;
131 }
132 } else if (subexpr->op == expr_VAR) {
133 hx509_env subenv;
134
135 subenv = find_variable(context, env, subexpr);
136 if (subenv == NULL)
137 return FALSE;
138
139 while (subenv) {
140 if (subenv->type != env_string)
141 continue;
142 if (strcmp(w, subenv->name) == 0)
143 return TRUE;
144 if (strcmp(w, subenv->u.string) == 0)
145 return TRUE;
146 subenv = subenv->next;
147 }
148
149 } else
150 _hx509_abort("hx509 eval IN unknown op: %d", (int)subexpr->op);
151
152 return FALSE;
153 }
154 default:
155 _hx509_abort("hx509 eval expr with unknown op: %d", (int)expr->op);
156 }
157 return FALSE;
158 }
159
160 int
_hx509_expr_eval(hx509_context context,hx509_env env,struct hx_expr * expr)161 _hx509_expr_eval(hx509_context context, hx509_env env, struct hx_expr *expr)
162 {
163 switch (expr->op) {
164 case op_TRUE:
165 return 1;
166 case op_FALSE:
167 return 0;
168 case op_NOT:
169 return ! _hx509_expr_eval(context, env, expr->arg1);
170 case op_AND:
171 return _hx509_expr_eval(context, env, expr->arg1) &&
172 _hx509_expr_eval(context, env, expr->arg2);
173 case op_OR:
174 return _hx509_expr_eval(context, env, expr->arg1) ||
175 _hx509_expr_eval(context, env, expr->arg2);
176 case op_COMP:
177 return eval_comp(context, env, expr->arg1);
178 default:
179 _hx509_abort("hx509 eval expr with unknown op: %d", (int)expr->op);
180 UNREACHABLE(return 0);
181 }
182 }
183
184 void
_hx509_expr_free(struct hx_expr * expr)185 _hx509_expr_free(struct hx_expr *expr)
186 {
187 switch (expr->op) {
188 case expr_STRING:
189 case expr_NUMBER:
190 free(expr->arg1);
191 break;
192 case expr_WORDS:
193 case expr_FUNCTION:
194 case expr_VAR:
195 free(expr->arg1);
196 if (expr->arg2)
197 _hx509_expr_free(expr->arg2);
198 break;
199 default:
200 if (expr->arg1)
201 _hx509_expr_free(expr->arg1);
202 if (expr->arg2)
203 _hx509_expr_free(expr->arg2);
204 break;
205 }
206 free(expr);
207 }
208
209 struct hx_expr *
_hx509_expr_parse(const char * buf)210 _hx509_expr_parse(const char *buf)
211 {
212 _hx509_expr_input.buf = buf;
213 _hx509_expr_input.length = strlen(buf);
214 _hx509_expr_input.offset = 0;
215 _hx509_expr_input.expr = NULL;
216
217 if (_hx509_expr_input.error) {
218 free(_hx509_expr_input.error);
219 _hx509_expr_input.error = NULL;
220 }
221
222 yyparse();
223
224 return _hx509_expr_input.expr;
225 }
226
227 void
_hx509_sel_yyerror(const char * s)228 _hx509_sel_yyerror (const char *s)
229 {
230 if (_hx509_expr_input.error)
231 free(_hx509_expr_input.error);
232
233 _hx509_expr_input.error = strdup(s);
234 }
235
236