1 |
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/* OpenBSD S/Key (skeylogin.c) |
2 |
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* |
3 |
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* Authors: |
4 |
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* Neil M. Haller <nmh@thumper.bellcore.com> |
5 |
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* Philip R. Karn <karn@chicago.qualcomm.com> |
6 |
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* John S. Walden <jsw@thumper.bellcore.com> |
7 |
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* Scott Chasin <chasin@crimelab.com> |
8 |
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* Todd C. Miller <Todd.Miller@courtesan.com> |
9 |
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* Angelos D. Keromytis <adk@adk.gr> |
10 |
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* |
11 |
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* S/Key verification check, lookups, and authentication. |
12 |
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* |
13 |
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* $OpenBSD: skeylogin.c,v 1.61 2017/04/17 21:55:20 deraadt Exp $ |
14 |
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*/ |
15 |
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16 |
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#ifdef QUOTA |
17 |
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#include <sys/quota.h> |
18 |
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#endif |
19 |
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#include <sys/stat.h> |
20 |
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#include <sys/time.h> |
21 |
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#include <sys/resource.h> |
22 |
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23 |
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#include <ctype.h> |
24 |
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#include <err.h> |
25 |
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#include <errno.h> |
26 |
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#include <fcntl.h> |
27 |
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#include <paths.h> |
28 |
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#include <poll.h> |
29 |
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#include <stdio.h> |
30 |
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#include <stdlib.h> |
31 |
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#include <string.h> |
32 |
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#include <time.h> |
33 |
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#include <unistd.h> |
34 |
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#include <limits.h> |
35 |
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#include <sha1.h> |
36 |
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37 |
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#include "skey.h" |
38 |
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39 |
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static void skey_fakeprompt(char *, char *); |
40 |
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static char *tgetline(int, char *, size_t, int); |
41 |
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static int skeygetent(int, struct skey *, const char *); |
42 |
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43 |
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/* |
44 |
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* Return an skey challenge string for user 'name'. If successful, |
45 |
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* fill in the caller's skey structure and return (0). If unsuccessful |
46 |
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* (e.g., if name is unknown) return (-1). |
47 |
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* |
48 |
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* The file read/write pointer is left at the start of the record. |
49 |
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*/ |
50 |
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int |
51 |
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skeychallenge2(int fd, struct skey *mp, char *name, char *ss) |
52 |
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{ |
53 |
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int rval; |
54 |
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55 |
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memset(mp, 0, sizeof(*mp)); |
56 |
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rval = skeygetent(fd, mp, name); |
57 |
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58 |
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switch (rval) { |
59 |
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case 0: /* Lookup succeeded, return challenge */ |
60 |
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(void)snprintf(ss, SKEY_MAX_CHALLENGE, |
61 |
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"otp-%.*s %d %.*s", SKEY_MAX_HASHNAME_LEN, |
62 |
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skey_get_algorithm(), mp->n - 1, |
63 |
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SKEY_MAX_SEED_LEN, mp->seed); |
64 |
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return (0); |
65 |
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66 |
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case 1: /* User not found */ |
67 |
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if (mp->keyfile) { |
68 |
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(void)fclose(mp->keyfile); |
69 |
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mp->keyfile = NULL; |
70 |
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} |
71 |
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/* FALLTHROUGH */ |
72 |
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73 |
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default: /* File error */ |
74 |
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skey_fakeprompt(name, ss); |
75 |
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return (-1); |
76 |
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} |
77 |
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} |
78 |
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79 |
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int |
80 |
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skeychallenge(struct skey *mp, char *name, char *ss) |
81 |
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{ |
82 |
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return (skeychallenge2(-1, mp, name, ss)); |
83 |
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} |
84 |
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85 |
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/* |
86 |
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* Get an entry in the One-time Password database and lock it. |
87 |
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* |
88 |
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* Return codes: |
89 |
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* -1: error in opening database or unable to lock entry |
90 |
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* 0: entry found, file R/W pointer positioned at beginning of record |
91 |
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* 1: entry not found |
92 |
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*/ |
93 |
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static int |
94 |
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skeygetent(int fd, struct skey *mp, const char *name) |
95 |
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{ |
96 |
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char *cp, filename[PATH_MAX], *last; |
97 |
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struct stat statbuf; |
98 |
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const char *errstr; |
99 |
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size_t nread; |
100 |
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FILE *keyfile; |
101 |
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102 |
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/* Check to see that /etc/skey has not been disabled. */ |
103 |
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if (stat(_PATH_SKEYDIR, &statbuf) != 0) |
104 |
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return (-1); |
105 |
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if ((statbuf.st_mode & ALLPERMS) == 0) { |
106 |
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errno = EPERM; |
107 |
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return (-1); |
108 |
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} |
109 |
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110 |
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if (fd == -1) { |
111 |
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/* Open the user's databse entry, creating it as needed. */ |
112 |
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if (snprintf(filename, sizeof(filename), "%s/%s", _PATH_SKEYDIR, |
113 |
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name) >= sizeof(filename)) { |
114 |
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errno = ENAMETOOLONG; |
115 |
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return (-1); |
116 |
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} |
117 |
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if ((fd = open(filename, O_RDWR | O_NOFOLLOW | O_NONBLOCK, |
118 |
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S_IRUSR | S_IWUSR)) == -1) { |
119 |
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if (errno == ENOENT) |
120 |
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goto not_found; |
121 |
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return (-1); |
122 |
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} |
123 |
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} |
124 |
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125 |
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/* Lock and stat the user's skey file. */ |
126 |
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if (flock(fd, LOCK_EX) != 0 || fstat(fd, &statbuf) != 0) { |
127 |
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close(fd); |
128 |
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return (-1); |
129 |
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} |
130 |
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if (statbuf.st_size == 0) |
131 |
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goto not_found; |
132 |
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133 |
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/* Sanity checks. */ |
134 |
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if ((statbuf.st_mode & ALLPERMS) != (S_IRUSR | S_IWUSR) || |
135 |
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!S_ISREG(statbuf.st_mode) || statbuf.st_nlink != 1 || |
136 |
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(keyfile = fdopen(fd, "r+")) == NULL) { |
137 |
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close(fd); |
138 |
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return (-1); |
139 |
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} |
140 |
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141 |
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/* At this point, we are committed. */ |
142 |
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mp->keyfile = keyfile; |
143 |
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144 |
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if ((nread = fread(mp->buf, 1, sizeof(mp->buf), keyfile)) == 0 || |
145 |
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!isspace((unsigned char)mp->buf[nread - 1])) |
146 |
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goto bad_keyfile; |
147 |
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mp->buf[nread - 1] = '\0'; |
148 |
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149 |
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if ((mp->logname = strtok_r(mp->buf, " \t\n\r", &last)) == NULL || |
150 |
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strcmp(mp->logname, name) != 0) |
151 |
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goto bad_keyfile; |
152 |
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if ((cp = strtok_r(NULL, " \t\n\r", &last)) == NULL) |
153 |
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goto bad_keyfile; |
154 |
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if (skey_set_algorithm(cp) == NULL) |
155 |
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goto bad_keyfile; |
156 |
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if ((cp = strtok_r(NULL, " \t\n\r", &last)) == NULL) |
157 |
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goto bad_keyfile; |
158 |
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mp->n = strtonum(cp, 0, UINT_MAX, &errstr); |
159 |
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if (errstr) |
160 |
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goto bad_keyfile; |
161 |
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if ((mp->seed = strtok_r(NULL, " \t\n\r", &last)) == NULL) |
162 |
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goto bad_keyfile; |
163 |
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if ((mp->val = strtok_r(NULL, " \t\n\r", &last)) == NULL) |
164 |
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goto bad_keyfile; |
165 |
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166 |
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(void)fseek(keyfile, 0L, SEEK_SET); |
167 |
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return (0); |
168 |
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169 |
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bad_keyfile: |
170 |
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fclose(keyfile); |
171 |
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return (-1); |
172 |
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173 |
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not_found: |
174 |
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/* No existing entry, fill in what we can and return */ |
175 |
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memset(mp, 0, sizeof(*mp)); |
176 |
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strlcpy(mp->buf, name, sizeof(mp->buf)); |
177 |
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mp->logname = mp->buf; |
178 |
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if (fd != -1) |
179 |
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close(fd); |
180 |
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return (1); |
181 |
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} |
182 |
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183 |
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/* |
184 |
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* Look up an entry in the One-time Password database and lock it. |
185 |
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* Zeroes out the passed in struct skey before using it. |
186 |
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* |
187 |
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* Return codes: |
188 |
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* -1: error in opening database or unable to lock entry |
189 |
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* 0: entry found, file R/W pointer positioned at beginning of record |
190 |
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* 1: entry not found |
191 |
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*/ |
192 |
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int |
193 |
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skeylookup(struct skey *mp, char *name) |
194 |
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{ |
195 |
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memset(mp, 0, sizeof(*mp)); |
196 |
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return (skeygetent(-1, mp, name)); |
197 |
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} |
198 |
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|
199 |
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/* |
200 |
|
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* Get the next entry in the One-time Password database. |
201 |
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* |
202 |
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* Return codes: |
203 |
|
|
* -1: error in opening database |
204 |
|
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* 0: next entry found and stored in mp |
205 |
|
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* 1: no more entries, keydir is closed. |
206 |
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*/ |
207 |
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int |
208 |
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skeygetnext(struct skey *mp) |
209 |
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{ |
210 |
|
|
struct dirent entry, *dp; |
211 |
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int rval; |
212 |
|
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|
213 |
|
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if (mp->keyfile != NULL) { |
214 |
|
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fclose(mp->keyfile); |
215 |
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mp->keyfile = NULL; |
216 |
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|
} |
217 |
|
|
|
218 |
|
|
/* Open _PATH_SKEYDIR if it exists, else return an error */ |
219 |
|
|
if (mp->keydir == NULL && (mp->keydir = opendir(_PATH_SKEYDIR)) == NULL) |
220 |
|
|
return (-1); |
221 |
|
|
|
222 |
|
|
rval = 1; |
223 |
|
|
while ((readdir_r(mp->keydir, &entry, &dp)) == 0 && dp == &entry) { |
224 |
|
|
/* Skip dot files and zero-length files. */ |
225 |
|
|
if (entry.d_name[0] != '.' && |
226 |
|
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(rval = skeygetent(-1, mp, entry.d_name)) != 1) |
227 |
|
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break; |
228 |
|
|
} |
229 |
|
|
|
230 |
|
|
if (dp == NULL) { |
231 |
|
|
closedir(mp->keydir); |
232 |
|
|
mp->keydir = NULL; |
233 |
|
|
} |
234 |
|
|
|
235 |
|
|
return (rval); |
236 |
|
|
} |
237 |
|
|
|
238 |
|
|
/* |
239 |
|
|
* Verify response to a S/Key challenge. |
240 |
|
|
* |
241 |
|
|
* Return codes: |
242 |
|
|
* -1: Error of some sort; database unchanged |
243 |
|
|
* 0: Verify successful, database updated |
244 |
|
|
* 1: Verify failed, database unchanged |
245 |
|
|
* |
246 |
|
|
* The database file is always closed by this call. |
247 |
|
|
*/ |
248 |
|
|
int |
249 |
|
|
skeyverify(struct skey *mp, char *response) |
250 |
|
|
{ |
251 |
|
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char key[SKEY_BINKEY_SIZE], fkey[SKEY_BINKEY_SIZE]; |
252 |
|
|
char filekey[SKEY_BINKEY_SIZE], *cp, *last; |
253 |
|
|
size_t nread; |
254 |
|
|
|
255 |
|
|
if (response == NULL) |
256 |
|
|
goto verify_failure; |
257 |
|
|
|
258 |
|
|
/* |
259 |
|
|
* The record should already be locked but lock it again |
260 |
|
|
* just to be safe. We don't wait for the lock to become |
261 |
|
|
* available since we should already have it... |
262 |
|
|
*/ |
263 |
|
|
if (flock(fileno(mp->keyfile), LOCK_EX | LOCK_NB) != 0) |
264 |
|
|
goto verify_failure; |
265 |
|
|
|
266 |
|
|
/* Convert response to binary */ |
267 |
|
|
rip(response); |
268 |
|
|
if (etob(key, response) != 1 && atob8(key, response) != 0) |
269 |
|
|
goto verify_failure; /* Neither english words nor ascii hex */ |
270 |
|
|
|
271 |
|
|
/* Compute fkey = f(key) */ |
272 |
|
|
(void)memcpy(fkey, key, sizeof(key)); |
273 |
|
|
f(fkey); |
274 |
|
|
|
275 |
|
|
/* |
276 |
|
|
* Reread the file record NOW in case it has been modified. |
277 |
|
|
* The only field we really need to worry about is mp->val. |
278 |
|
|
*/ |
279 |
|
|
(void)fseek(mp->keyfile, 0L, SEEK_SET); |
280 |
|
|
if ((nread = fread(mp->buf, 1, sizeof(mp->buf), mp->keyfile)) == 0 || |
281 |
|
|
!isspace((unsigned char)mp->buf[nread - 1])) |
282 |
|
|
goto verify_failure; |
283 |
|
|
if ((mp->logname = strtok_r(mp->buf, " \t\r\n", &last)) == NULL) |
284 |
|
|
goto verify_failure; |
285 |
|
|
if ((cp = strtok_r(NULL, " \t\r\n", &last)) == NULL) |
286 |
|
|
goto verify_failure; |
287 |
|
|
if ((cp = strtok_r(NULL, " \t\r\n", &last)) == NULL) |
288 |
|
|
goto verify_failure; |
289 |
|
|
if ((mp->seed = strtok_r(NULL, " \t\r\n", &last)) == NULL) |
290 |
|
|
goto verify_failure; |
291 |
|
|
if ((mp->val = strtok_r(NULL, " \t\r\n", &last)) == NULL) |
292 |
|
|
goto verify_failure; |
293 |
|
|
|
294 |
|
|
/* Convert file value to hex and compare. */ |
295 |
|
|
atob8(filekey, mp->val); |
296 |
|
|
if (memcmp(filekey, fkey, SKEY_BINKEY_SIZE) != 0) |
297 |
|
|
goto verify_failure; /* Wrong response */ |
298 |
|
|
|
299 |
|
|
/* |
300 |
|
|
* Update key in database. |
301 |
|
|
* XXX - check return values of things that write to disk. |
302 |
|
|
*/ |
303 |
|
|
btoa8(mp->val,key); |
304 |
|
|
mp->n--; |
305 |
|
|
(void)fseek(mp->keyfile, 0L, SEEK_SET); |
306 |
|
|
(void)fprintf(mp->keyfile, "%s\n%s\n%d\n%s\n%s\n", mp->logname, |
307 |
|
|
skey_get_algorithm(), mp->n, mp->seed, mp->val); |
308 |
|
|
(void)fflush(mp->keyfile); |
309 |
|
|
(void)ftruncate(fileno(mp->keyfile), ftello(mp->keyfile)); |
310 |
|
|
(void)fclose(mp->keyfile); |
311 |
|
|
mp->keyfile = NULL; |
312 |
|
|
return (0); |
313 |
|
|
|
314 |
|
|
verify_failure: |
315 |
|
|
(void)fclose(mp->keyfile); |
316 |
|
|
mp->keyfile = NULL; |
317 |
|
|
return (-1); |
318 |
|
|
} |
319 |
|
|
|
320 |
|
|
/* |
321 |
|
|
* skey_haskey() |
322 |
|
|
* |
323 |
|
|
* Returns: 1 user doesn't exist, -1 file error, 0 user exists. |
324 |
|
|
* |
325 |
|
|
*/ |
326 |
|
|
int |
327 |
|
|
skey_haskey(char *username) |
328 |
|
|
{ |
329 |
|
|
struct skey skey; |
330 |
|
|
int i; |
331 |
|
|
|
332 |
|
|
i = skeylookup(&skey, username); |
333 |
|
|
if (skey.keyfile != NULL) { |
334 |
|
|
fclose(skey.keyfile); |
335 |
|
|
skey.keyfile = NULL; |
336 |
|
|
} |
337 |
|
|
return (i); |
338 |
|
|
} |
339 |
|
|
|
340 |
|
|
/* |
341 |
|
|
* skey_keyinfo() |
342 |
|
|
* |
343 |
|
|
* Returns the current sequence number and |
344 |
|
|
* seed for the passed user. |
345 |
|
|
* |
346 |
|
|
*/ |
347 |
|
|
char * |
348 |
|
|
skey_keyinfo(char *username) |
349 |
|
|
{ |
350 |
|
|
static char str[SKEY_MAX_CHALLENGE]; |
351 |
|
|
struct skey skey; |
352 |
|
|
int i; |
353 |
|
|
|
354 |
|
|
i = skeychallenge(&skey, username, str); |
355 |
|
|
if (i == -1) |
356 |
|
|
return (0); |
357 |
|
|
|
358 |
|
|
if (skey.keyfile != NULL) { |
359 |
|
|
fclose(skey.keyfile); |
360 |
|
|
skey.keyfile = NULL; |
361 |
|
|
} |
362 |
|
|
return (str); |
363 |
|
|
} |
364 |
|
|
|
365 |
|
|
/* |
366 |
|
|
* skey_passcheck() |
367 |
|
|
* |
368 |
|
|
* Check to see if answer is the correct one to the current |
369 |
|
|
* challenge. |
370 |
|
|
* |
371 |
|
|
* Returns: 0 success, -1 failure |
372 |
|
|
* |
373 |
|
|
*/ |
374 |
|
|
int |
375 |
|
|
skey_passcheck(char *username, char *passwd) |
376 |
|
|
{ |
377 |
|
|
struct skey skey; |
378 |
|
|
int i; |
379 |
|
|
|
380 |
|
|
i = skeylookup(&skey, username); |
381 |
|
|
if (i == -1 || i == 1) |
382 |
|
|
return (-1); |
383 |
|
|
|
384 |
|
|
if (skeyverify(&skey, passwd) == 0) |
385 |
|
|
return (skey.n); |
386 |
|
|
|
387 |
|
|
return (-1); |
388 |
|
|
} |
389 |
|
|
|
390 |
|
|
#define ROUND(x) (((x)[0] << 24) + (((x)[1]) << 16) + (((x)[2]) << 8) + \ |
391 |
|
|
((x)[3])) |
392 |
|
|
|
393 |
|
|
/* |
394 |
|
|
* hash_collapse() |
395 |
|
|
*/ |
396 |
|
|
static u_int32_t |
397 |
|
|
hash_collapse(u_char *s) |
398 |
|
|
{ |
399 |
|
|
int len, target; |
400 |
|
|
u_int32_t i; |
401 |
|
|
|
402 |
|
|
if ((strlen(s) % sizeof(u_int32_t)) == 0) |
403 |
|
|
target = strlen(s); /* Multiple of 4 */ |
404 |
|
|
else |
405 |
|
|
target = strlen(s) - (strlen(s) % sizeof(u_int32_t)); |
406 |
|
|
|
407 |
|
|
for (i = 0, len = 0; len < target; len += 4) |
408 |
|
|
i ^= ROUND(s + len); |
409 |
|
|
|
410 |
|
|
return i; |
411 |
|
|
} |
412 |
|
|
|
413 |
|
|
/* |
414 |
|
|
* skey_fakeprompt() |
415 |
|
|
* |
416 |
|
|
* Generate a fake prompt for the specified user. |
417 |
|
|
* |
418 |
|
|
*/ |
419 |
|
|
static void |
420 |
|
|
skey_fakeprompt(char *username, char *skeyprompt) |
421 |
|
|
{ |
422 |
|
|
char secret[SKEY_MAX_SEED_LEN], pbuf[SKEY_MAX_PW_LEN+1], *p, *u; |
423 |
|
|
u_char *up; |
424 |
|
|
SHA1_CTX ctx; |
425 |
|
|
u_int ptr; |
426 |
|
|
int i; |
427 |
|
|
|
428 |
|
|
/* |
429 |
|
|
* Base first 4 chars of seed on hostname. |
430 |
|
|
* Add some filler for short hostnames if necessary. |
431 |
|
|
*/ |
432 |
|
|
if (gethostname(pbuf, sizeof(pbuf)) == -1) |
433 |
|
|
*(p = pbuf) = '.'; |
434 |
|
|
else |
435 |
|
|
for (p = pbuf; isalnum((unsigned char)*p); p++) |
436 |
|
|
if (isalpha((unsigned char)*p) && |
437 |
|
|
isupper((unsigned char)*p)) |
438 |
|
|
*p = (char)tolower((unsigned char)*p); |
439 |
|
|
if (*p && pbuf - p < 4) |
440 |
|
|
(void)strncpy(p, "asjd", 4 - (pbuf - p)); |
441 |
|
|
pbuf[4] = '\0'; |
442 |
|
|
|
443 |
|
|
/* Hash the username if possible */ |
444 |
|
|
if ((up = SHA1Data(username, strlen(username), NULL)) != NULL) { |
445 |
|
|
/* Collapse the hash */ |
446 |
|
|
ptr = hash_collapse(up); |
447 |
|
|
explicit_bzero(up, strlen(up)); |
448 |
|
|
|
449 |
|
|
/* Put that in your pipe and smoke it */ |
450 |
|
|
arc4random_buf(secret, sizeof(secret)); |
451 |
|
|
|
452 |
|
|
/* Hash secret value with username */ |
453 |
|
|
SHA1Init(&ctx); |
454 |
|
|
SHA1Update(&ctx, secret, sizeof(secret)); |
455 |
|
|
SHA1Update(&ctx, username, strlen(username)); |
456 |
|
|
SHA1End(&ctx, up); |
457 |
|
|
|
458 |
|
|
/* Zero out */ |
459 |
|
|
explicit_bzero(secret, sizeof(secret)); |
460 |
|
|
|
461 |
|
|
/* Now hash the hash */ |
462 |
|
|
SHA1Init(&ctx); |
463 |
|
|
SHA1Update(&ctx, up, strlen(up)); |
464 |
|
|
SHA1End(&ctx, up); |
465 |
|
|
|
466 |
|
|
ptr = hash_collapse(up + 4); |
467 |
|
|
|
468 |
|
|
for (i = 4; i < 9; i++) { |
469 |
|
|
pbuf[i] = (ptr % 10) + '0'; |
470 |
|
|
ptr /= 10; |
471 |
|
|
} |
472 |
|
|
pbuf[i] = '\0'; |
473 |
|
|
|
474 |
|
|
/* Sequence number */ |
475 |
|
|
ptr = ((up[2] + up[3]) % 99) + 1; |
476 |
|
|
|
477 |
|
|
freezero(up, 20); /* SHA1 specific */ |
478 |
|
|
|
479 |
|
|
(void)snprintf(skeyprompt, SKEY_MAX_CHALLENGE, |
480 |
|
|
"otp-%.*s %d %.*s", SKEY_MAX_HASHNAME_LEN, |
481 |
|
|
skey_get_algorithm(), ptr, SKEY_MAX_SEED_LEN, pbuf); |
482 |
|
|
} else { |
483 |
|
|
/* Base last 8 chars of seed on username */ |
484 |
|
|
u = username; |
485 |
|
|
i = 8; |
486 |
|
|
p = &pbuf[4]; |
487 |
|
|
do { |
488 |
|
|
if (*u == 0) { |
489 |
|
|
/* Pad remainder with zeros */ |
490 |
|
|
while (--i >= 0) |
491 |
|
|
*p++ = '0'; |
492 |
|
|
break; |
493 |
|
|
} |
494 |
|
|
|
495 |
|
|
*p++ = (*u++ % 10) + '0'; |
496 |
|
|
} while (--i != 0); |
497 |
|
|
pbuf[12] = '\0'; |
498 |
|
|
|
499 |
|
|
(void)snprintf(skeyprompt, SKEY_MAX_CHALLENGE, |
500 |
|
|
"otp-%.*s %d %.*s", SKEY_MAX_HASHNAME_LEN, |
501 |
|
|
skey_get_algorithm(), 99, SKEY_MAX_SEED_LEN, pbuf); |
502 |
|
|
} |
503 |
|
|
} |
504 |
|
|
|
505 |
|
|
/* |
506 |
|
|
* skey_authenticate() |
507 |
|
|
* |
508 |
|
|
* Used when calling program will allow input of the user's |
509 |
|
|
* response to the challenge. |
510 |
|
|
* |
511 |
|
|
* Returns: 0 success, -1 failure |
512 |
|
|
* |
513 |
|
|
*/ |
514 |
|
|
int |
515 |
|
|
skey_authenticate(char *username) |
516 |
|
|
{ |
517 |
|
|
char pbuf[SKEY_MAX_PW_LEN+1], skeyprompt[SKEY_MAX_CHALLENGE+1]; |
518 |
|
|
struct skey skey; |
519 |
|
|
int i; |
520 |
|
|
|
521 |
|
|
/* Get the S/Key challenge (may be fake) */ |
522 |
|
|
i = skeychallenge(&skey, username, skeyprompt); |
523 |
|
|
(void)fprintf(stderr, "%s\nResponse: ", skeyprompt); |
524 |
|
|
(void)fflush(stderr); |
525 |
|
|
|
526 |
|
|
/* Time out on user input after 2 minutes */ |
527 |
|
|
tgetline(fileno(stdin), pbuf, sizeof(pbuf), 120); |
528 |
|
|
sevenbit(pbuf); |
529 |
|
|
(void)rewind(stdin); |
530 |
|
|
|
531 |
|
|
/* Is it a valid response? */ |
532 |
|
|
if (i == 0 && skeyverify(&skey, pbuf) == 0) { |
533 |
|
|
if (skey.n < 5) { |
534 |
|
|
(void)fprintf(stderr, |
535 |
|
|
"\nWarning! Key initialization needed soon. (%d logins left)\n", |
536 |
|
|
skey.n); |
537 |
|
|
} |
538 |
|
|
return (0); |
539 |
|
|
} |
540 |
|
|
return (-1); |
541 |
|
|
} |
542 |
|
|
|
543 |
|
|
/* |
544 |
|
|
* Unlock current entry in the One-time Password database. |
545 |
|
|
* |
546 |
|
|
* Return codes: |
547 |
|
|
* -1: unable to lock the record |
548 |
|
|
* 0: record was successfully unlocked |
549 |
|
|
*/ |
550 |
|
|
int |
551 |
|
|
skey_unlock(struct skey *mp) |
552 |
|
|
{ |
553 |
|
|
if (mp->logname == NULL || mp->keyfile == NULL) |
554 |
|
|
return (-1); |
555 |
|
|
|
556 |
|
|
return (flock(fileno(mp->keyfile), LOCK_UN)); |
557 |
|
|
} |
558 |
|
|
|
559 |
|
|
/* |
560 |
|
|
* Get a line of input (optionally timing out) and place it in buf. |
561 |
|
|
*/ |
562 |
|
|
static char * |
563 |
|
|
tgetline(int fd, char *buf, size_t bufsiz, int timeout) |
564 |
|
|
{ |
565 |
|
|
struct pollfd pfd[1]; |
566 |
|
|
size_t left; |
567 |
|
|
char c, *cp; |
568 |
|
|
ssize_t ss; |
569 |
|
|
int n; |
570 |
|
|
|
571 |
|
|
if (bufsiz == 0) |
572 |
|
|
return (NULL); /* sanity */ |
573 |
|
|
|
574 |
|
|
cp = buf; |
575 |
|
|
left = bufsiz; |
576 |
|
|
|
577 |
|
|
/* |
578 |
|
|
* Timeout of <= 0 means no timeout. |
579 |
|
|
*/ |
580 |
|
|
if (timeout > 0) { |
581 |
|
|
timeout *= 1000; /* convert to milliseconds */ |
582 |
|
|
|
583 |
|
|
pfd[0].fd = fd; |
584 |
|
|
pfd[0].events = POLLIN; |
585 |
|
|
while (--left) { |
586 |
|
|
/* Poll until we are ready or we time out */ |
587 |
|
|
while ((n = poll(pfd, 1, timeout)) == -1 && |
588 |
|
|
(errno == EINTR || errno == EAGAIN)) |
589 |
|
|
; |
590 |
|
|
if (n <= 0 || |
591 |
|
|
(pfd[0].revents & (POLLERR|POLLHUP|POLLNVAL))) |
592 |
|
|
break; /* timeout or error */ |
593 |
|
|
|
594 |
|
|
/* Read a character, exit loop on error, EOF or EOL */ |
595 |
|
|
ss = read(fd, &c, 1); |
596 |
|
|
if (ss != 1 || c == '\n' || c == '\r') |
597 |
|
|
break; |
598 |
|
|
*cp++ = c; |
599 |
|
|
} |
600 |
|
|
} else { |
601 |
|
|
/* Keep reading until out of space, EOF, error, or newline */ |
602 |
|
|
while (--left && read(fd, &c, 1) == 1 && c != '\n' && c != '\r') |
603 |
|
|
*cp++ = c; |
604 |
|
|
} |
605 |
|
|
*cp = '\0'; |
606 |
|
|
|
607 |
|
|
return (cp == buf ? NULL : buf); |
608 |
|
|
} |