1 #include <u.h>
2 #include <libc.h>
3 #include <regexp.h>
4 #include <libsec.h>
5 #include <libString.h>
6 #include <bio.h>
7 #include "dat.h"
8 
9 int debug;
10 
11 enum
12 {
13 	Tregexp=	(1<<0),		/* ~ */
14 	Texact=		(1<<1),		/* = */
15 };
16 
17 typedef struct Pattern Pattern;
18 struct Pattern
19 {
20 	Pattern	*next;
21 	int	type;
22 	char	*arg;
23 	int	bang;
24 };
25 
26 String	*patternpath;
27 Pattern	*patterns;
28 String	*mbox;
29 
30 static void
31 usage(void)
32 {
33 	fprint(2, "usage: %s 'check|add' patternfile addr [addr*]\n", argv0);
34 	exits("usage");
35 }
36 
37 /*
38  *  convert string to lower case
39  */
40 static void
41 mklower(char *p)
42 {
43 	int c;
44 
45 	for(; *p; p++){
46 		c = *p;
47 		if(c <= 'Z' && c >= 'A')
48 			*p = c - 'A' + 'a';
49 	}
50 }
51 
52 /*
53  *  simplify an address, reduce to a domain
54  */
55 static String*
56 simplify(char *addr)
57 {
58 	int dots;
59 	char *p, *at;
60 	String *s;
61 
62 	mklower(addr);
63 	at = strchr(addr, '@');
64 	if(at == nil){
65 		/* local address, make it an exact match */
66 		s = s_copy("=");
67 		s_append(s, addr);
68 		return s;
69 	}
70 
71 	/* copy up to the '@' sign */
72 	at++;
73 	s = s_copy("~");
74 	for(p = addr; p < at; p++){
75 		if(strchr(".*+?(|)\\[]^$", *p))
76 			s_putc(s, '\\');
77 		s_putc(s, *p);
78 	}
79 
80 	/* just any address matching the two most significant domain elements */
81 	s_append(s, "(.*\\.)?");
82 	p = addr+strlen(addr);
83 	dots = 0;
84 	for(; p > at; p--){
85 		if(*p != '.')
86 			continue;
87 		if(dots++ > 0){
88 			p++;
89 			break;
90 		}
91 	}
92 	for(; *p; p++){
93 		if(strchr(".*+?(|)\\[]^$", *p) != 0)
94 			s_putc(s, '\\');
95 		s_putc(s, *p);
96 	}
97 	s_terminate(s);
98 
99 	return s;
100 }
101 
102 /*
103  *  link patterns in order
104  */
105 static int
106 newpattern(int type, char *arg, int bang)
107 {
108 	Pattern *p;
109 	static Pattern *last;
110 
111 	mklower(arg);
112 
113 	p = mallocz(sizeof *p, 1);
114 	if(p == nil)
115 		return -1;
116 	if(type == Tregexp){
117 		p->arg = malloc(strlen(arg)+3);
118 		if(p->arg == nil){
119 			free(p);
120 			return -1;
121 		}
122 		p->arg[0] = 0;
123 		strcat(p->arg, "^");
124 		strcat(p->arg, arg);
125 		strcat(p->arg, "$");
126 	} else {
127 		p->arg = strdup(arg);
128 		if(p->arg == nil){
129 			free(p);
130 			return -1;
131 		}
132 	}
133 	p->type = type;
134 	p->bang = bang;
135 	if(last == nil)
136 		patterns = p;
137 	else
138 		last->next = p;
139 	last = p;
140 
141 	return 0;
142 }
143 
144 /*
145  *  patterns are either
146  *	~ regular expression
147  *	= exact match string
148  *
149  *  all comparisons are case insensitive
150  */
151 static int
152 readpatterns(char *path)
153 {
154 	Biobuf *b;
155 	char *p;
156 	char *token[2];
157 	int n;
158 	int bang;
159 
160 	b = Bopen(path, OREAD);
161 	if(b == nil)
162 		return -1;
163 	while((p = Brdline(b, '\n')) != nil){
164 		p[Blinelen(b)-1] = 0;
165 		n = tokenize(p, token, 2);
166 		if(n == 0)
167 			continue;
168 
169 		mklower(token[0]);
170 		p = token[0];
171 		if(*p == '!'){
172 			p++;
173 			bang = 1;
174 		} else
175 			bang = 0;
176 
177 		if(*p == '='){
178 			if(newpattern(Texact, p+1, bang) < 0)
179 				return -1;
180 		} else if(*p == '~'){
181 			if(newpattern(Tregexp, p+1, bang) < 0)
182 				return -1;
183 		} else if(strcmp(token[0], "#include") == 0 && n == 2)
184 			readpatterns(token[1]);
185 	}
186 	Bterm(b);
187 	return 0;
188 }
189 
190 /* fuck, shit, bugger, damn */
191 void regerror(char *err)
192 {
193 	USED(err);
194 }
195 
196 /*
197  *  check lower case version of address agains patterns
198  */
199 static Pattern*
200 checkaddr(char *arg)
201 {
202 	Pattern *p;
203 	Reprog *rp;
204 	String *s;
205 
206 	s = s_copy(arg);
207 	mklower(s_to_c(s));
208 
209 	for(p = patterns; p != nil; p = p->next)
210 		switch(p->type){
211 		case Texact:
212 			if(strcmp(p->arg, s_to_c(s)) == 0){
213 				free(s);
214 				return p;
215 			}
216 			break;
217 		case Tregexp:
218 			rp = regcomp(p->arg);
219 			if(rp == nil)
220 				continue;
221 			if(regexec(rp, s_to_c(s), nil, 0)){
222 				free(rp);
223 				free(s);
224 				return p;
225 			}
226 			free(rp);
227 			break;
228 		}
229 	s_free(s);
230 	return 0;
231 }
232 static char*
233 check(int argc, char **argv)
234 {
235 	int i;
236 	Addr *a;
237 	Pattern *p;
238 	int matchedbang;
239 
240 	matchedbang = 0;
241 	for(i = 0; i < argc; i++){
242 		a = readaddrs(argv[i], nil);
243 		for(; a != nil; a = a->next){
244 			p = checkaddr(a->val);
245 			if(p == nil)
246 				continue;
247 			if(p->bang)
248 				matchedbang = 1;
249 			else
250 				return nil;
251 		}
252 	}
253 	if(matchedbang)
254 		return "!match";
255 	else
256 		return "no match";
257 }
258 
259 /*
260  *  add anything that isn't already matched, all matches are lower case
261  */
262 static char*
263 add(char *pp, int argc, char **argv)
264 {
265 	int fd, i;
266 	String *s;
267 	char *cp;
268 	Addr *a;
269 
270 	a = nil;
271 	for(i = 0; i < argc; i++)
272 		a = readaddrs(argv[i], a);
273 
274 	fd = open(pp, OWRITE);
275 	seek(fd, 0, 2);
276 	for(; a != nil; a = a->next){
277 		if(checkaddr(a->val))
278 			continue;
279 		s = simplify(a->val);
280 		cp = s_to_c(s);
281 		fprint(fd, "%q\t%q\n", cp, a->val);
282 		if(*cp == '=')
283 			newpattern(Texact, cp+1, 0);
284 		else if(*cp == '~')
285 			newpattern(Tregexp, cp+1, 0);
286 		s_free(s);
287 	}
288 	close(fd);
289 	return nil;
290 }
291 
292 void
293 main(int argc, char **argv)
294 {
295 	char *patternpath;
296 
297 	ARGBEGIN {
298 	case 'd':
299 		debug++;
300 		break;
301 	} ARGEND;
302 
303 	quotefmtinstall();
304 
305 	if(argc < 3)
306 		usage();
307 
308 	patternpath = argv[1];
309 	readpatterns(patternpath);
310 	if(strcmp(argv[0], "add") == 0)
311 		exits(add(patternpath, argc-2, argv+2));
312 	else if(strcmp(argv[0], "check") == 0)
313 		exits(check(argc-2, argv+2));
314 	else
315 		usage();
316 }