Annotation of src/usr.bin/login/failedlogin.c, Revision 1.15
1.15 ! deraadt 1: /* $OpenBSD: failedlogin.c,v 1.14 2003/06/17 21:56:25 millert Exp $ */
1.1 millert 2:
3: /*
4: * Copyright (c) 1996 Todd C. Miller <Todd.Miller@courtesan.com>
5: *
1.13 millert 6: * Permission to use, copy, modify, and distribute this software for any
7: * purpose with or without fee is hereby granted, provided that the above
8: * copyright notice and this permission notice appear in all copies.
1.1 millert 9: *
1.14 millert 10: * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11: * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12: * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13: * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14: * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15: * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16: * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
1.1 millert 17: */
18:
19: /*
20: * failedlogin.c
21: * Log to failedlogin file and read from it, reporting the number of
22: * failed logins since the last good login and when/from where
23: * the last failed login was.
24: */
25:
26: #include <sys/param.h>
27: #include <sys/stat.h>
28: #include <sys/time.h>
29:
1.7 millert 30: #include <fcntl.h>
1.1 millert 31: #include <stdio.h>
32: #include <string.h>
33: #include <unistd.h>
34: #include <utmp.h>
35:
36: #include "pathnames.h"
37:
38: struct badlogin {
39: char bl_line[UT_LINESIZE]; /* tty used */
1.2 millert 40: char bl_name[UT_NAMESIZE]; /* remote username */
1.1 millert 41: char bl_host[UT_HOSTSIZE]; /* remote host */
1.2 millert 42: time_t bl_time; /* time of the login attempt */
43: size_t count; /* number of bad logins */
1.1 millert 44: };
1.10 pvalchev 45:
1.11 millert 46: void log_failedlogin(uid_t, char *, char *, char *);
47: int check_failedlogin(uid_t);
1.1 millert 48:
49: /*
50: * Log a bad login to the failedlogin file.
51: */
52: void
1.12 deraadt 53: log_failedlogin(uid_t uid, char *host, char *name, char *tty)
1.1 millert 54: {
55: struct badlogin failedlogin;
56: int fd;
57:
58: /* Add O_CREAT if you want to create failedlogin if it doesn't exist */
59: if ((fd = open(_PATH_FAILEDLOGIN, O_RDWR, S_IREAD|S_IWRITE)) >= 0) {
1.5 millert 60: (void)lseek(fd, (off_t)uid * sizeof(failedlogin), SEEK_SET);
1.1 millert 61:
62: /* Read in last bad login so can get the count */
63: if (read(fd, (char *)&failedlogin, sizeof(failedlogin)) !=
64: sizeof(failedlogin) || failedlogin.bl_time == 0)
65: memset((void *)&failedlogin, 0, sizeof(failedlogin));
66:
1.5 millert 67: (void)lseek(fd, (off_t)uid * sizeof(failedlogin), SEEK_SET);
1.1 millert 68: /* Increment count of bad logins */
69: ++failedlogin.count;
70: (void)time(&failedlogin.bl_time);
71: strncpy(failedlogin.bl_line, tty, sizeof(failedlogin.bl_line));
72: if (host)
73: strncpy(failedlogin.bl_host, host, sizeof(failedlogin.bl_host));
74: else
75: *failedlogin.bl_host = '\0'; /* NULL host field */
1.2 millert 76: if (name)
77: strncpy(failedlogin.bl_name, name, sizeof(failedlogin.bl_name));
78: else
79: *failedlogin.bl_name = '\0'; /* NULL name field */
1.1 millert 80: (void)write(fd, (char *)&failedlogin, sizeof(failedlogin));
81: (void)close(fd);
82: }
83: }
84:
85: /*
86: * Check the failedlogin file and report about the number of unsuccessful
87: * logins and info about the last one in lastlogin style.
88: * NOTE: zeros the count field since this is assumed to be called after the
89: * user has been validated.
90: */
91: int
1.12 deraadt 92: check_failedlogin(uid_t uid)
1.1 millert 93: {
94: struct badlogin failedlogin;
1.12 deraadt 95: int fd, was_bad = 0;
1.1 millert 96:
97: (void)memset((void *)&failedlogin, 0, sizeof(failedlogin));
98:
99: if ((fd = open(_PATH_FAILEDLOGIN, O_RDWR, 0)) >= 0) {
1.5 millert 100: (void)lseek(fd, (off_t)uid * sizeof(failedlogin), SEEK_SET);
1.1 millert 101: if (read(fd, (char *)&failedlogin, sizeof(failedlogin)) ==
102: sizeof(failedlogin) && failedlogin.count > 0 ) {
103: /* There was a bad login */
104: was_bad = 1;
105: if (failedlogin.count > 1)
1.9 millert 106: (void)printf("There have been %lu unsuccessful "
107: "login attempts to your account.\n",
108: (u_long)failedlogin.count);
1.6 pjanzen 109: (void)printf("Last unsuccessful login: %.*s", 24-5,
1.1 millert 110: (char *)ctime(&failedlogin.bl_time));
111: (void)printf(" on %.*s",
112: (int)sizeof(failedlogin.bl_line),
1.12 deraadt 113: failedlogin.bl_line);
1.3 art 114: if (*failedlogin.bl_host != '\0') {
1.2 millert 115: if (*failedlogin.bl_name != '\0')
116: (void)printf(" from %.*s@%.*s",
117: (int)sizeof(failedlogin.bl_name),
118: failedlogin.bl_name,
119: (int)sizeof(failedlogin.bl_host),
120: failedlogin.bl_host);
121: else
122: (void)printf(" from %.*s",
123: (int)sizeof(failedlogin.bl_host),
124: failedlogin.bl_host);
1.3 art 125: }
1.1 millert 126: (void)putchar('\n');
127:
128: /* Reset since this is a good login and write record */
129: failedlogin.count = 0;
1.5 millert 130: (void)lseek(fd, (off_t)uid * sizeof(failedlogin),
131: SEEK_SET);
132: (void)write(fd, (char *)&failedlogin,
133: sizeof(failedlogin));
1.1 millert 134: }
135: (void)close(fd);
136: }
137: return(was_bad);
138: }