1 /* $OpenBSD: head.c,v 1.13 2023/03/08 04:43:11 guenther Exp $ */
2 /* $NetBSD: head.c,v 1.6 1996/12/28 07:11:03 tls Exp $ */
3
4 /*
5 * Copyright (c) 1980, 1993
6 * The Regents of the University of California. 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 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33 #include "rcv.h"
34 #include "extern.h"
35
36 /*
37 * Mail -- a mail program
38 *
39 * Routines for processing and detecting headlines.
40 */
41
42 /*
43 * See if the passed line buffer is a mail header.
44 * Return true if yes. Note the extreme pains to
45 * accommodate all funny formats.
46 */
47 int
ishead(char * linebuf)48 ishead(char *linebuf)
49 {
50 char *cp;
51 struct headline hl;
52 char parbuf[BUFSIZ];
53
54 cp = linebuf;
55 if (*cp++ != 'F' || *cp++ != 'r' || *cp++ != 'o' || *cp++ != 'm' ||
56 *cp++ != ' ')
57 return(0);
58 parse(linebuf, &hl, parbuf);
59 if (hl.l_from == NULL || hl.l_date == NULL) {
60 fail(linebuf, "No from or date field");
61 return(0);
62 }
63 if (!isdate(hl.l_date)) {
64 fail(linebuf, "Date field not legal date");
65 return(0);
66 }
67 /*
68 * I guess we got it!
69 */
70 return(1);
71 }
72
73 void
fail(char * linebuf,char * reason)74 fail(char *linebuf, char *reason)
75 {
76
77 /*
78 if (value("debug") == NULL)
79 return;
80 fprintf(stderr, "\"%s\"\nnot a header because %s\n", linebuf, reason);
81 */
82 }
83
84 /*
85 * Split a headline into its useful components.
86 * Copy the line into dynamic string space, then set
87 * pointers into the copied line in the passed headline
88 * structure. Actually, it scans.
89 */
90 void
parse(char * line,struct headline * hl,char * pbuf)91 parse(char *line, struct headline *hl, char *pbuf)
92 {
93 char *cp, *sp;
94 char word[LINESIZE];
95
96 hl->l_from = NULL;
97 hl->l_tty = NULL;
98 hl->l_date = NULL;
99 cp = line;
100 sp = pbuf;
101 /*
102 * Skip over "From" first.
103 */
104 cp = nextword(cp, word);
105 cp = nextword(cp, word);
106 if (*word)
107 hl->l_from = copyin(word, &sp);
108 if (cp != NULL && strncmp(cp, "tty", 3) == 0) {
109 cp = nextword(cp, word);
110 hl->l_tty = copyin(word, &sp);
111 }
112 if (cp != NULL)
113 hl->l_date = copyin(cp, &sp);
114 }
115
116 /*
117 * Copy the string on the left into the string on the right
118 * and bump the right (reference) string pointer by the length.
119 * Thus, dynamically allocate space in the right string, copying
120 * the left string into it.
121 */
122 char *
copyin(char * src,char ** space)123 copyin(char *src, char **space)
124 {
125 char *cp, *top;
126
127 top = cp = *space;
128 while ((*cp++ = *src++) != '\0')
129 ;
130 *space = cp;
131 return(top);
132 }
133
134 /*
135 * Test to see if the passed string is a ctime(3) generated
136 * date string as documented in the manual. The template
137 * below is used as the criterion of correctness.
138 * Also, we check for a possible trailing time zone using
139 * the tmztype template.
140 */
141
142 /*
143 * 'A' An upper case char
144 * 'a' A lower case char
145 * ' ' A space
146 * '0' A digit
147 * 'O' A digit or space
148 * 'p' A punctuation char
149 * 'P' A punctuation char or space
150 * ':' A colon
151 * 'N' A new line
152 */
153
154 /*
155 * Yuck. If the mail file is created by Sys V (Solaris),
156 * there are no seconds in the time...
157 */
158
159 /*
160 * If the mail is created by another program such as imapd, it might
161 * have timezone as <-|+>nnnn (-0800 for instance) at the end.
162 */
163
164 static char *date_formats[] = {
165 "Aaa Aaa O0 00:00:00 0000", /* Mon Jan 01 23:59:59 2001 */
166 "Aaa Aaa O0 00:00:00 AAA 0000", /* Mon Jan 01 23:59:59 PST 2001 */
167 "Aaa Aaa O0 00:00:00 0000 p0000", /* Mon Jan 01 23:59:59 2001 -0800 */
168 "Aaa Aaa O0 00:00 0000", /* Mon Jan 01 23:59 2001 */
169 "Aaa Aaa O0 00:00 AAA 0000", /* Mon Jan 01 23:59 PST 2001 */
170 "Aaa Aaa O0 00:00 0000 p0000", /* Mon Jan 01 23:59 2001 -0800 */
171 ""
172 };
173
174 int
isdate(char * date)175 isdate(char *date)
176 {
177 int i;
178
179 for(i = 0; *date_formats[i]; i++) {
180 if (cmatch(date, date_formats[i]))
181 return 1;
182 }
183 return 0;
184 }
185
186 /*
187 * Match the given string (cp) against the given template (tp).
188 * Return 1 if they match, 0 if they don't
189 */
190 int
cmatch(char * cp,char * tp)191 cmatch(char *cp, char *tp)
192 {
193
194 while (*cp && *tp)
195 switch (*tp++) {
196 case 'a':
197 if (!islower((unsigned char)*cp++))
198 return(0);
199 break;
200 case 'A':
201 if (!isupper((unsigned char)*cp++))
202 return(0);
203 break;
204 case ' ':
205 if (*cp++ != ' ')
206 return(0);
207 break;
208 case '0':
209 if (!isdigit((unsigned char)*cp++))
210 return(0);
211 break;
212 case 'O':
213 if (*cp != ' ' && !isdigit((unsigned char)*cp))
214 return(0);
215 cp++;
216 break;
217 case 'p':
218 if (!ispunct((unsigned char)*cp++))
219 return(0);
220 break;
221 case 'P':
222 if (*cp != ' ' && !ispunct((unsigned char)*cp))
223 return(0);
224 cp++;
225 break;
226 case ':':
227 if (*cp++ != ':')
228 return(0);
229 break;
230 case 'N':
231 if (*cp++ != '\n')
232 return(0);
233 break;
234 }
235 if (*cp || *tp)
236 return(0);
237 return(1);
238 }
239
240 /*
241 * Collect a liberal (space, tab delimited) word into the word buffer
242 * passed. Also, return a pointer to the next word following that,
243 * or NULL if none follow.
244 */
245 char *
nextword(char * wp,char * wbuf)246 nextword(char *wp, char *wbuf)
247 {
248 int c;
249
250 if (wp == NULL) {
251 *wbuf = 0;
252 return(NULL);
253 }
254 while ((c = (unsigned char)*wp++) && c != ' ' && c != '\t') {
255 *wbuf++ = c;
256 if (c == '"') {
257 while ((c = (unsigned char)*wp++) && c != '"')
258 *wbuf++ = c;
259 if (c == '"')
260 *wbuf++ = c;
261 else
262 wp--;
263 }
264 }
265 *wbuf = '\0';
266 for (; c == ' ' || c == '\t'; c = (unsigned char)*wp++)
267 ;
268 if (c == 0)
269 return(NULL);
270 return(wp - 1);
271 }
272