Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame^] | 1 | /* |
| 2 | |
| 3 | login.c |
| 4 | |
| 5 | Author: Tatu Ylonen <ylo@cs.hut.fi> |
| 6 | |
| 7 | Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland |
| 8 | All rights reserved |
| 9 | |
| 10 | Created: Fri Mar 24 14:51:08 1995 ylo |
| 11 | |
| 12 | This file performs some of the things login(1) normally does. We cannot |
| 13 | easily use something like login -p -h host -f user, because there are |
| 14 | several different logins around, and it is hard to determined what kind of |
| 15 | login the current system has. Also, we want to be able to execute commands |
| 16 | on a tty. |
| 17 | |
| 18 | */ |
| 19 | |
| 20 | #include "includes.h" |
| 21 | RCSID("$Id: login.c,v 1.1 1999/10/27 03:42:44 damien Exp $"); |
| 22 | |
| 23 | #include <utmp.h> |
| 24 | #include "ssh.h" |
| 25 | |
| 26 | /* Returns the time when the user last logged in. Returns 0 if the |
| 27 | information is not available. This must be called before record_login. |
| 28 | The host the user logged in from will be returned in buf. */ |
| 29 | |
| 30 | /* Returns the time when the user last logged in (or 0 if no previous login |
| 31 | is found). The name of the host used last time is returned in buf. */ |
| 32 | |
| 33 | unsigned long get_last_login_time(uid_t uid, const char *logname, |
| 34 | char *buf, unsigned int bufsize) |
| 35 | { |
| 36 | struct lastlog ll; |
| 37 | char *lastlog; |
| 38 | int fd; |
| 39 | |
| 40 | lastlog = _PATH_LASTLOG; |
| 41 | |
| 42 | buf[0] = '\0'; |
| 43 | |
| 44 | fd = open(lastlog, O_RDONLY); |
| 45 | if (fd < 0) |
| 46 | return 0; |
| 47 | lseek(fd, (off_t)((long)uid * sizeof(ll)), SEEK_SET); |
| 48 | if (read(fd, &ll, sizeof(ll)) != sizeof(ll)) |
| 49 | { |
| 50 | close(fd); |
| 51 | return 0; |
| 52 | } |
| 53 | close(fd); |
| 54 | if (bufsize > sizeof(ll.ll_host) + 1) |
| 55 | bufsize = sizeof(ll.ll_host) + 1; |
| 56 | strncpy(buf, ll.ll_host, bufsize - 1); |
| 57 | buf[bufsize - 1] = 0; |
| 58 | return ll.ll_time; |
| 59 | } |
| 60 | |
| 61 | /* Records that the user has logged in. I these parts of operating systems |
| 62 | were more standardized. */ |
| 63 | |
| 64 | void record_login(int pid, const char *ttyname, const char *user, uid_t uid, |
| 65 | const char *host, struct sockaddr_in *addr) |
| 66 | { |
| 67 | int fd; |
| 68 | struct lastlog ll; |
| 69 | char *lastlog; |
| 70 | |
| 71 | struct utmp u; |
| 72 | const char *utmp, *wtmp; |
| 73 | |
| 74 | /* Construct an utmp/wtmp entry. */ |
| 75 | memset(&u, 0, sizeof(u)); |
| 76 | strncpy(u.ut_line, ttyname + 5, sizeof(u.ut_line)); |
| 77 | u.ut_time = time(NULL); |
| 78 | strncpy(u.ut_name, user, sizeof(u.ut_name)); |
| 79 | strncpy(u.ut_host, host, sizeof(u.ut_host)); |
| 80 | |
| 81 | /* Figure out the file names. */ |
| 82 | utmp = _PATH_UTMP; |
| 83 | wtmp = _PATH_WTMP; |
| 84 | |
| 85 | login(&u); |
| 86 | |
| 87 | lastlog = _PATH_LASTLOG; |
| 88 | |
| 89 | /* Update lastlog unless actually recording a logout. */ |
| 90 | if (strcmp(user, "") != 0) |
| 91 | { |
| 92 | /* It is safer to bzero the lastlog structure first because some |
| 93 | systems might have some extra fields in it (e.g. SGI) */ |
| 94 | memset(&ll, 0, sizeof(ll)); |
| 95 | |
| 96 | /* Update lastlog. */ |
| 97 | ll.ll_time = time(NULL); |
| 98 | strncpy(ll.ll_line, ttyname + 5, sizeof(ll.ll_line)); |
| 99 | strncpy(ll.ll_host, host, sizeof(ll.ll_host)); |
| 100 | fd = open(lastlog, O_RDWR); |
| 101 | if (fd >= 0) |
| 102 | { |
| 103 | lseek(fd, (off_t)((long)uid * sizeof(ll)), SEEK_SET); |
| 104 | if (write(fd, &ll, sizeof(ll)) != sizeof(ll)) |
| 105 | log("Could not write %.100s: %.100s", lastlog, strerror(errno)); |
| 106 | close(fd); |
| 107 | } |
| 108 | } |
| 109 | } |
| 110 | |
| 111 | /* Records that the user has logged out. */ |
| 112 | |
| 113 | void record_logout(int pid, const char *ttyname) |
| 114 | { |
| 115 | const char *line = ttyname + 5; /* /dev/ttyq8 -> ttyq8 */ |
| 116 | if (logout(line)) |
| 117 | logwtmp(line, "", ""); |
| 118 | } |