1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1980, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #include "rcv.h"
33 #include <sys/file.h>
34 #include <sys/wait.h>
35
36 #include <unistd.h>
37 #include <paths.h>
38 #include <errno.h>
39 #include "extern.h"
40
41 /*
42 * Mail -- a mail program
43 *
44 * File I/O.
45 */
46
47 extern int wait_status;
48
49 /*
50 * Set up the input pointers while copying the mail file into /tmp.
51 */
52 void
setptr(FILE * ibuf,off_t offset)53 setptr(FILE *ibuf, off_t offset)
54 {
55 int c, count;
56 char *cp, *cp2;
57 struct message this;
58 FILE *mestmp;
59 int maybe, inhead;
60 char linebuf[LINESIZE], pathbuf[PATHSIZE];
61 int omsgCount;
62
63 /* Get temporary file. */
64 (void)snprintf(pathbuf, sizeof(pathbuf), "%s/mail.XXXXXXXXXX", tmpdir);
65 if ((c = mkstemp(pathbuf)) == -1 || (mestmp = Fdopen(c, "r+")) == NULL)
66 err(1, "can't open %s", pathbuf);
67 (void)rm(pathbuf);
68
69 if (offset == 0) {
70 msgCount = 0;
71 } else {
72 /* Seek into the file to get to the new messages */
73 (void)fseeko(ibuf, offset, SEEK_SET);
74 /*
75 * We need to make "offset" a pointer to the end of
76 * the temp file that has the copy of the mail file.
77 * If any messages have been edited, this will be
78 * different from the offset into the mail file.
79 */
80 (void)fseeko(otf, (off_t)0, SEEK_END);
81 offset = ftello(otf);
82 }
83 omsgCount = msgCount;
84 maybe = 1;
85 inhead = 0;
86 this.m_flag = MUSED|MNEW;
87 this.m_size = 0;
88 this.m_lines = 0;
89 this.m_block = 0;
90 this.m_offset = 0;
91 for (;;) {
92 if (fgets(linebuf, sizeof(linebuf), ibuf) == NULL) {
93 if (append(&this, mestmp))
94 errx(1, "temporary file");
95 makemessage(mestmp, omsgCount);
96 return;
97 }
98 count = strlen(linebuf);
99 /*
100 * Transforms lines ending in <CR><LF> to just <LF>.
101 * This allows mail to be able to read Eudora mailboxes.
102 */
103 if (count >= 2 && linebuf[count - 1] == '\n' &&
104 linebuf[count - 2] == '\r') {
105 count--;
106 linebuf[count - 1] = '\n';
107 }
108
109 (void)fwrite(linebuf, sizeof(*linebuf), count, otf);
110 if (ferror(otf))
111 errx(1, "/tmp");
112 if (count)
113 linebuf[count - 1] = '\0';
114 if (maybe && linebuf[0] == 'F' && ishead(linebuf)) {
115 msgCount++;
116 if (append(&this, mestmp))
117 errx(1, "temporary file");
118 this.m_flag = MUSED|MNEW;
119 this.m_size = 0;
120 this.m_lines = 0;
121 this.m_block = blockof(offset);
122 this.m_offset = boffsetof(offset);
123 inhead = 1;
124 } else if (linebuf[0] == 0) {
125 inhead = 0;
126 } else if (inhead) {
127 for (cp = linebuf, cp2 = "status";; cp++) {
128 if ((c = *cp2++) == '\0') {
129 while (isspace((unsigned char)*cp++))
130 ;
131 if (cp[-1] != ':')
132 break;
133 while ((c = *cp++) != '\0')
134 if (c == 'R')
135 this.m_flag |= MREAD;
136 else if (c == 'O')
137 this.m_flag &= ~MNEW;
138 inhead = 0;
139 break;
140 }
141 if (*cp != c && *cp != toupper((unsigned char)c))
142 break;
143 }
144 }
145 offset += count;
146 this.m_size += count;
147 this.m_lines++;
148 maybe = linebuf[0] == 0;
149 }
150 }
151
152 /*
153 * Drop the passed line onto the passed output buffer.
154 * If a write error occurs, return -1, else the count of
155 * characters written, including the newline if requested.
156 */
157 int
putline(FILE * obuf,char * linebuf,int outlf)158 putline(FILE *obuf, char *linebuf, int outlf)
159 {
160 int c;
161
162 c = strlen(linebuf);
163 (void)fwrite(linebuf, sizeof(*linebuf), c, obuf);
164 if (outlf) {
165 fprintf(obuf, "\n");
166 c++;
167 }
168 if (ferror(obuf))
169 return (-1);
170 return (c);
171 }
172
173 /*
174 * Read up a line from the specified input into the line
175 * buffer. Return the number of characters read. Do not
176 * include the newline (or carriage return) at the end.
177 */
178 int
readline(FILE * ibuf,char * linebuf,int linesize)179 readline(FILE *ibuf, char *linebuf, int linesize)
180 {
181 int n;
182
183 clearerr(ibuf);
184 if (fgets(linebuf, linesize, ibuf) == NULL)
185 return (-1);
186 n = strlen(linebuf);
187 if (n > 0 && linebuf[n - 1] == '\n')
188 linebuf[--n] = '\0';
189 if (n > 0 && linebuf[n - 1] == '\r')
190 linebuf[--n] = '\0';
191 return (n);
192 }
193
194 /*
195 * Return a file buffer all ready to read up the
196 * passed message pointer.
197 */
198 FILE *
setinput(struct message * mp)199 setinput(struct message *mp)
200 {
201
202 (void)fflush(otf);
203 if (fseeko(itf,
204 positionof(mp->m_block, mp->m_offset), SEEK_SET) < 0)
205 err(1, "fseeko");
206 return (itf);
207 }
208
209 /*
210 * Take the data out of the passed ghost file and toss it into
211 * a dynamically allocated message structure.
212 */
213 void
makemessage(FILE * f,int omsgCount)214 makemessage(FILE *f, int omsgCount)
215 {
216 size_t size;
217 struct message *nmessage;
218
219 size = (msgCount + 1) * sizeof(struct message);
220 nmessage = (struct message *)realloc(message, size);
221 if (nmessage == NULL)
222 errx(1, "Insufficient memory for %d messages\n",
223 msgCount);
224 if (omsgCount == 0 || message == NULL)
225 dot = nmessage;
226 else
227 dot = nmessage + (dot - message);
228 message = nmessage;
229 size -= (omsgCount + 1) * sizeof(struct message);
230 (void)fflush(f);
231 (void)lseek(fileno(f), (off_t)sizeof(*message), 0);
232 if (read(fileno(f), (void *)&message[omsgCount], size) != size)
233 errx(1, "Message temporary file corrupted");
234 message[msgCount].m_size = 0;
235 message[msgCount].m_lines = 0;
236 (void)Fclose(f);
237 }
238
239 /*
240 * Append the passed message descriptor onto the temp file.
241 * If the write fails, return 1, else 0
242 */
243 int
append(struct message * mp,FILE * f)244 append(struct message *mp, FILE *f)
245 {
246 return (fwrite((char *)mp, sizeof(*mp), 1, f) != 1);
247 }
248
249 /*
250 * Delete a file, but only if the file is a plain file.
251 */
252 int
rm(char * name)253 rm(char *name)
254 {
255 struct stat sb;
256
257 if (stat(name, &sb) < 0)
258 return (-1);
259 if (!S_ISREG(sb.st_mode)) {
260 errno = EISDIR;
261 return (-1);
262 }
263 return (unlink(name));
264 }
265
266 static int sigdepth; /* depth of holdsigs() */
267 static sigset_t nset, oset;
268 /*
269 * Hold signals SIGHUP, SIGINT, and SIGQUIT.
270 */
271 void
holdsigs(void)272 holdsigs(void)
273 {
274
275 if (sigdepth++ == 0) {
276 (void)sigemptyset(&nset);
277 (void)sigaddset(&nset, SIGHUP);
278 (void)sigaddset(&nset, SIGINT);
279 (void)sigaddset(&nset, SIGQUIT);
280 (void)sigprocmask(SIG_BLOCK, &nset, &oset);
281 }
282 }
283
284 /*
285 * Release signals SIGHUP, SIGINT, and SIGQUIT.
286 */
287 void
relsesigs(void)288 relsesigs(void)
289 {
290
291 if (--sigdepth == 0)
292 (void)sigprocmask(SIG_SETMASK, &oset, NULL);
293 }
294
295 /*
296 * Determine the size of the file possessed by
297 * the passed buffer.
298 */
299 off_t
fsize(FILE * iob)300 fsize(FILE *iob)
301 {
302 struct stat sbuf;
303
304 if (fstat(fileno(iob), &sbuf) < 0)
305 return (0);
306 return (sbuf.st_size);
307 }
308
309 /*
310 * Evaluate the string given as a new mailbox name.
311 * Supported meta characters:
312 * % for my system mail box
313 * %user for user's system mail box
314 * # for previous file
315 * & invoker's mbox file
316 * +file file in folder directory
317 * any shell meta character
318 * Return the file name as a dynamic string.
319 */
320 char *
expand(char * name)321 expand(char *name)
322 {
323 char xname[PATHSIZE];
324 char cmdbuf[PATHSIZE]; /* also used for file names */
325 int pid, l;
326 char *cp, *sh;
327 int pivec[2];
328 struct stat sbuf;
329
330 /*
331 * The order of evaluation is "%" and "#" expand into constants.
332 * "&" can expand into "+". "+" can expand into shell meta characters.
333 * Shell meta characters expand into constants.
334 * This way, we make no recursive expansion.
335 */
336 switch (*name) {
337 case '%':
338 findmail(name[1] ? name + 1 : myname, xname, sizeof(xname));
339 return (savestr(xname));
340 case '#':
341 if (name[1] != 0)
342 break;
343 if (prevfile[0] == 0) {
344 printf("No previous file\n");
345 return (NULL);
346 }
347 return (savestr(prevfile));
348 case '&':
349 if (name[1] == 0 && (name = value("MBOX")) == NULL)
350 name = "~/mbox";
351 /* fall through */
352 }
353 if (name[0] == '+' && getfold(cmdbuf, sizeof(cmdbuf)) >= 0) {
354 (void)snprintf(xname, sizeof(xname), "%s/%s", cmdbuf, name + 1);
355 name = savestr(xname);
356 }
357 /* catch the most common shell meta character */
358 if (name[0] == '~' && homedir != NULL &&
359 (name[1] == '/' || name[1] == '\0')) {
360 (void)snprintf(xname, sizeof(xname), "%s%s", homedir, name + 1);
361 name = savestr(xname);
362 }
363 if (!strpbrk(name, "~{[*?$`'\"\\"))
364 return (savestr(name));
365 if (pipe(pivec) < 0) {
366 warn("pipe");
367 return (NULL);
368 }
369 (void)snprintf(cmdbuf, sizeof(cmdbuf), "echo %s", name);
370 if ((sh = value("SHELL")) == NULL)
371 sh = _PATH_CSHELL;
372 pid = start_command(sh, 0, -1, pivec[1], "-c", cmdbuf, NULL);
373 if (pid < 0) {
374 (void)close(pivec[0]);
375 (void)close(pivec[1]);
376 return (NULL);
377 }
378 (void)close(pivec[1]);
379 l = read(pivec[0], xname, BUFSIZ);
380 (void)close(pivec[0]);
381 if (wait_child(pid) < 0 && WIFSIGNALED(wait_status) &&
382 WTERMSIG(wait_status) != SIGPIPE) {
383 fprintf(stderr, "\"%s\": Expansion failed.\n", name);
384 return (NULL);
385 }
386 if (l < 0) {
387 warn("read");
388 return (NULL);
389 }
390 if (l == 0) {
391 fprintf(stderr, "\"%s\": No match.\n", name);
392 return (NULL);
393 }
394 if (l == BUFSIZ) {
395 fprintf(stderr, "\"%s\": Expansion buffer overflow.\n", name);
396 return (NULL);
397 }
398 xname[l] = '\0';
399 for (cp = &xname[l-1]; *cp == '\n' && cp > xname; cp--)
400 ;
401 cp[1] = '\0';
402 if (strchr(xname, ' ') && stat(xname, &sbuf) < 0) {
403 fprintf(stderr, "\"%s\": Ambiguous.\n", name);
404 return (NULL);
405 }
406 return (savestr(xname));
407 }
408
409 /*
410 * Determine the current folder directory name.
411 */
412 int
getfold(char * name,int namelen)413 getfold(char *name, int namelen)
414 {
415 char *folder;
416 int copylen;
417
418 if ((folder = value("folder")) == NULL)
419 return (-1);
420 if (*folder == '/')
421 copylen = strlcpy(name, folder, namelen);
422 else
423 copylen = snprintf(name, namelen, "%s/%s",
424 homedir ? homedir : ".", folder);
425 return (copylen < 0 || copylen >= namelen ? (-1) : (0));
426 }
427
428 /*
429 * Return the name of the dead.letter file.
430 */
431 char *
getdeadletter(void)432 getdeadletter(void)
433 {
434 char *cp;
435
436 if ((cp = value("DEAD")) == NULL || (cp = expand(cp)) == NULL)
437 cp = expand("~/dead.letter");
438 else if (*cp != '/') {
439 char buf[PATHSIZE];
440
441 (void)snprintf(buf, sizeof(buf), "~/%s", cp);
442 cp = expand(buf);
443 }
444 return (cp);
445 }
446