| 1 | /*- |
| 2 | * Copyright (c) 1990 The Regents of the University of California. |
| 3 | * All rights reserved. |
| 4 | * |
| 5 | * %sccs.include.redist.c% |
| 6 | */ |
| 7 | |
| 8 | #ifndef lint |
| 9 | char copyright[] = |
| 10 | "@(#) Copyright (c) 1990 The Regents of the University of California.\n\ |
| 11 | All rights reserved.\n"; |
| 12 | #endif /* not lint */ |
| 13 | |
| 14 | #ifndef lint |
| 15 | static char sccsid[] = "@(#)mail.local.c 5.6 (Berkeley) %G%"; |
| 16 | #endif /* not lint */ |
| 17 | |
| 18 | #include <sys/param.h> |
| 19 | #include <sys/stat.h> |
| 20 | #include <sys/socket.h> |
| 21 | #include <netinet/in.h> |
| 22 | #include <syslog.h> |
| 23 | #include <fcntl.h> |
| 24 | #include <netdb.h> |
| 25 | #include <pwd.h> |
| 26 | #include <time.h> |
| 27 | #include <unistd.h> |
| 28 | #include <errno.h> |
| 29 | #include <stdio.h> |
| 30 | #include <stdlib.h> |
| 31 | #include <string.h> |
| 32 | #include "pathnames.h" |
| 33 | |
| 34 | #define FATAL 1 |
| 35 | #define NOTFATAL 0 |
| 36 | |
| 37 | int deliver __P((int, char *)); |
| 38 | void err __P((int, const char *, ...)); |
| 39 | void notifybiff __P((char *)); |
| 40 | int store __P((char *)); |
| 41 | void usage __P((void)); |
| 42 | |
| 43 | main(argc, argv) |
| 44 | int argc; |
| 45 | char **argv; |
| 46 | { |
| 47 | extern int optind; |
| 48 | extern char *optarg; |
| 49 | struct passwd *pw; |
| 50 | int ch, fd, eval; |
| 51 | uid_t uid; |
| 52 | char *from; |
| 53 | |
| 54 | openlog("mail.local", LOG_PERROR, LOG_MAIL); |
| 55 | |
| 56 | from = NULL; |
| 57 | while ((ch = getopt(argc, argv, "df:r:")) != EOF) |
| 58 | switch(ch) { |
| 59 | case 'd': /* backward compatible */ |
| 60 | break; |
| 61 | case 'f': |
| 62 | case 'r': /* backward compatible */ |
| 63 | if (from) |
| 64 | err(FATAL, "multiple -f options"); |
| 65 | from = optarg; |
| 66 | break; |
| 67 | case '?': |
| 68 | default: |
| 69 | usage(); |
| 70 | } |
| 71 | argc -= optind; |
| 72 | argv += optind; |
| 73 | |
| 74 | if (!*argv) |
| 75 | usage(); |
| 76 | |
| 77 | /* |
| 78 | * If from not specified, use the name from getlogin() if the |
| 79 | * uid matches, otherwise, use the name from the password file |
| 80 | * corresponding to the uid. |
| 81 | */ |
| 82 | uid = getuid(); |
| 83 | if (!from && (!(from = getlogin()) || |
| 84 | !(pw = getpwnam(from)) || pw->pw_uid != uid)) |
| 85 | from = (pw = getpwuid(uid)) ? pw->pw_name : "???"; |
| 86 | |
| 87 | fd = store(from); |
| 88 | for (eval = 0; *argv; ++argv) |
| 89 | eval |= deliver(fd, *argv); |
| 90 | exit(eval); |
| 91 | } |
| 92 | |
| 93 | store(from) |
| 94 | char *from; |
| 95 | { |
| 96 | FILE *fp; |
| 97 | time_t tval; |
| 98 | int fd, eline; |
| 99 | char *tn, line[2048]; |
| 100 | |
| 101 | tn = strdup(_PATH_LOCTMP); |
| 102 | if ((fd = mkstemp(tn)) == -1 || !(fp = fdopen(fd, "w+"))) |
| 103 | err(FATAL, "unable to open temporary file"); |
| 104 | (void)unlink(tn); |
| 105 | free(tn); |
| 106 | |
| 107 | (void)time(&tval); |
| 108 | (void)fprintf(fp, "From %s %s", from, ctime(&tval)); |
| 109 | |
| 110 | line[0] = '\0'; |
| 111 | for (eline = 1; fgets(line, sizeof(line), stdin);) { |
| 112 | if (line[0] == '\n') |
| 113 | eline = 1; |
| 114 | else { |
| 115 | if (eline && line[0] == 'F' && !bcmp(line, "From ", 5)) |
| 116 | (void)putc('>', fp); |
| 117 | eline = 0; |
| 118 | } |
| 119 | (void)fprintf(fp, "%s", line); |
| 120 | if (ferror(fp)) |
| 121 | break; |
| 122 | } |
| 123 | |
| 124 | /* If message not newline terminated, need an extra. */ |
| 125 | if (!index(line, '\n')) |
| 126 | (void)putc('\n', fp); |
| 127 | /* Output a newline; note, empty messages are allowed. */ |
| 128 | (void)putc('\n', fp); |
| 129 | |
| 130 | (void)fflush(fp); |
| 131 | if (ferror(fp)) |
| 132 | err(FATAL, "temporary file write error"); |
| 133 | return(fd); |
| 134 | } |
| 135 | |
| 136 | deliver(fd, name) |
| 137 | int fd; |
| 138 | char *name; |
| 139 | { |
| 140 | struct stat sb; |
| 141 | struct passwd *pw; |
| 142 | int created, mbfd, nr, nw, off, rval; |
| 143 | char biffmsg[100], buf[8*1024], path[MAXPATHLEN]; |
| 144 | off_t curoff, lseek(); |
| 145 | |
| 146 | /* |
| 147 | * Disallow delivery to unknown names -- special mailboxes can be |
| 148 | * handled in the sendmail aliases file. |
| 149 | */ |
| 150 | if (!(pw = getpwnam(name))) { |
| 151 | err(NOTFATAL, "unknown name: %s", name); |
| 152 | return(1); |
| 153 | } |
| 154 | |
| 155 | (void)sprintf(path, "%s/%s", _PATH_MAILDIR, name); |
| 156 | |
| 157 | if (!(created = lstat(path, &sb)) && |
| 158 | (sb.st_nlink != 1 || S_ISLNK(sb.st_mode))) { |
| 159 | err(NOTFATAL, "%s: linked file", path); |
| 160 | return(1); |
| 161 | } |
| 162 | |
| 163 | /* |
| 164 | * There's a race here -- two processes think they both created |
| 165 | * the file. This means the file cannot be unlinked. |
| 166 | */ |
| 167 | if ((mbfd = |
| 168 | open(path, O_APPEND|O_CREAT|O_WRONLY, S_IRUSR|S_IWUSR)) < 0) { |
| 169 | err(NOTFATAL, "%s: %s", path, strerror(errno)); |
| 170 | return(1); |
| 171 | } |
| 172 | |
| 173 | rval = 0; |
| 174 | /* XXX: Open should allow flock'ing the file; see 4.4BSD. */ |
| 175 | if (flock(mbfd, LOCK_EX)) { |
| 176 | err(NOTFATAL, "%s: %s", path, strerror(errno)); |
| 177 | rval = 1; |
| 178 | goto bad; |
| 179 | } |
| 180 | |
| 181 | curoff = lseek(mbfd, 0L, SEEK_END); |
| 182 | (void)sprintf(biffmsg, "%s@%ld\n", name, curoff); |
| 183 | if (lseek(fd, 0L, SEEK_SET) == (off_t)-1) { |
| 184 | err(FATAL, "temporary file: %s", strerror(errno)); |
| 185 | rval = 1; |
| 186 | goto bad; |
| 187 | } |
| 188 | |
| 189 | while ((nr = read(fd, buf, sizeof(buf))) > 0) |
| 190 | for (off = 0; off < nr; nr -= nw, off += nw) |
| 191 | if ((nw = write(mbfd, buf + off, nr)) < 0) { |
| 192 | err(NOTFATAL, "%s: %s", path, strerror(errno)); |
| 193 | goto trunc; |
| 194 | } |
| 195 | if (nr < 0) { |
| 196 | err(FATAL, "temporary file: %s", strerror(errno)); |
| 197 | trunc: (void)ftruncate(mbfd, curoff); |
| 198 | rval = 1; |
| 199 | } |
| 200 | |
| 201 | /* |
| 202 | * Set the owner and group. Historically, binmail repeated this at |
| 203 | * each mail delivery. We no longer do this, assuming that if the |
| 204 | * ownership or permissions were changed there was a reason for doing |
| 205 | * so. |
| 206 | */ |
| 207 | bad: if (created) |
| 208 | (void)fchown(mbfd, pw->pw_uid, pw->pw_gid); |
| 209 | |
| 210 | (void)fsync(mbfd); /* Don't wait for update. */ |
| 211 | (void)close(mbfd); /* Implicit unlock. */ |
| 212 | |
| 213 | if (!rval) |
| 214 | notifybiff(biffmsg); |
| 215 | return(rval); |
| 216 | } |
| 217 | |
| 218 | void |
| 219 | notifybiff(msg) |
| 220 | char *msg; |
| 221 | { |
| 222 | static struct sockaddr_in addr; |
| 223 | static int f = -1; |
| 224 | struct hostent *hp; |
| 225 | struct servent *sp; |
| 226 | int len; |
| 227 | |
| 228 | if (!addr.sin_family) { |
| 229 | /* Be silent if biff service not available. */ |
| 230 | if (!(sp = getservbyname("biff", "udp"))) |
| 231 | return; |
| 232 | if (!(hp = gethostbyname("localhost"))) { |
| 233 | err(NOTFATAL, "localhost: %s", strerror(errno)); |
| 234 | return; |
| 235 | } |
| 236 | addr.sin_family = hp->h_addrtype; |
| 237 | bcopy(hp->h_addr, &addr.sin_addr, hp->h_length); |
| 238 | addr.sin_port = sp->s_port; |
| 239 | } |
| 240 | if (f < 0 && (f = socket(AF_INET, SOCK_DGRAM, 0)) == -1) { |
| 241 | err(NOTFATAL, "socket: %s", strerror(errno)); |
| 242 | return; |
| 243 | } |
| 244 | len = strlen(msg) + 1; |
| 245 | if (sendto(f, msg, len, 0, (struct sockaddr *)&addr, sizeof(addr)) |
| 246 | != len) |
| 247 | err(NOTFATAL, "sendto biff: %s", strerror(errno)); |
| 248 | } |
| 249 | |
| 250 | void |
| 251 | usage() |
| 252 | { |
| 253 | err(FATAL, "usage: mail.local [-f from] user ..."); |
| 254 | } |
| 255 | |
| 256 | #if __STDC__ |
| 257 | #include <stdarg.h> |
| 258 | #else |
| 259 | #include <varargs.h> |
| 260 | #endif |
| 261 | |
| 262 | void |
| 263 | #if __STDC__ |
| 264 | err(int isfatal, const char *fmt, ...) |
| 265 | #else |
| 266 | err(isfatal, fmt) |
| 267 | int isfatal; |
| 268 | char *fmt; |
| 269 | va_dcl |
| 270 | #endif |
| 271 | { |
| 272 | va_list ap; |
| 273 | #if __STDC__ |
| 274 | va_start(ap, fmt); |
| 275 | #else |
| 276 | va_start(ap); |
| 277 | #endif |
| 278 | vsyslog(LOG_ERR, fmt, ap); |
| 279 | va_end(ap); |
| 280 | if (isfatal) |
| 281 | exit(1); |
| 282 | } |