1 /*
2 * This is a small test program for testing libpamc against the
3 * secret@here agent. It does the same as the test.secret@here perl
4 * script in this directory, but via the libpamc API.
5 */
6
7 #include <stdio.h>
8 #include <stdint.h>
9 #include <string.h>
10 #include <security/pam_client.h>
11 #include <ctype.h>
12
13 struct internal_packet {
14 int length;
15 int at;
16 char *buffer;
17 };
18
19
20 void append_data(struct internal_packet *packet, int extra, const char *data)
21 {
22 if ((extra + packet->at) >= packet->length) {
23 if (packet->length == 0) {
24 packet->length = 1000;
25 }
26 /* make sure we have at least a char extra space available */
27 while (packet->length <= (extra + packet->at)) {
28 packet->length <<= 1;
29 }
30 packet->buffer = realloc(packet->buffer, packet->length);
31 if (packet->buffer == NULL) {
32 fprintf(stderr, "out of memory\n");
33 exit(1);
34 }
35 }
36
37 if (data != NULL) {
38 memcpy(packet->at + packet->buffer, data, extra);
39 }
40 packet->at += extra;
41
42 /* assisting string manipulation */
43 packet->buffer[packet->at] = '\0';
44 }
45
46 void append_string(struct internal_packet *packet, const char *string,
47 int with_nul)
48 {
49 append_data(packet, strlen(string) + (with_nul ? 1:0), string);
50 }
51
52 char *identify_secret(char *identity)
53 {
54 struct internal_packet temp_packet;
55 FILE *secrets;
56 int length_id;
57
58 temp_packet.length = temp_packet.at = 0;
59 temp_packet.buffer = NULL;
60
61 append_string(&temp_packet, "/home/", 0);
62 append_string(&temp_packet, getlogin(), 0);
63 append_string(&temp_packet, "/.secret@here", 1);
64
65 secrets = fopen(temp_packet.buffer, "r");
66 if (secrets == NULL) {
67 fprintf(stderr, "server: failed to open\n [%s]\n",
68 temp_packet.buffer);
69 exit(1);
70 }
71
72 length_id = strlen(identity);
73 for (;;) {
74 char *secret = NULL;
75 temp_packet.at = 0;
76
77 if (fgets(temp_packet.buffer, temp_packet.length, secrets) == NULL) {
78 fclose(secrets);
79 return NULL;
80 }
81
82 if (memcmp(temp_packet.buffer, identity, length_id)) {
83 continue;
84 }
85
86 fclose(secrets);
87 for (secret=temp_packet.buffer; *secret; ++secret) {
88 if (*secret == ' ' || *secret == '\n' || *secret == '\t') {
89 break;
90 }
91 }
92 for (; *secret; ++secret) {
93 if (!(*secret == ' ' || *secret == '\n' || *secret == '\t')) {
94 break;
95 }
96 }
97
98 for (temp_packet.buffer=secret; *temp_packet.buffer;
99 ++temp_packet.buffer) {
100 if (*temp_packet.buffer == ' ' || *temp_packet.buffer == '\n'
101 || *temp_packet.buffer == '\t') {
102 break;
103 }
104 }
105 if (*temp_packet.buffer) {
106 *temp_packet.buffer = '\0';
107 }
108
109 return secret;
110 }
111
112 /* NOT REACHED */
113 }
114
115 /*
116 * This is a hack, and is fundamentally insecure. All our secrets will be
117 * displayed on the command line for someone doing 'ps' to see. This
118 * is just for programming convenience in this instance, since this
119 * program is simply a regression test. The pam_secret module should
120 * not do this, but make use of md5 routines directly.
121 */
122
123 char *create_digest(int length, const char *raw)
124 {
125 struct internal_packet temp_packet;
126 FILE *pipe;
127
128 temp_packet.length = temp_packet.at = 0;
129 temp_packet.buffer = NULL;
130
131 append_string(&temp_packet, "echo -n '", 0);
132 append_string(&temp_packet, raw, 0);
133 append_string(&temp_packet, "'|/usr/bin/md5sum -", 1);
134
135 fprintf(stderr, "am attempting to run [%s]\n", temp_packet.buffer);
136
137 pipe = popen(temp_packet.buffer, "r");
138 if (pipe == NULL) {
139 fprintf(stderr, "server: failed to run\n [%s]\n", temp_packet.buffer);
140 exit(1);
141 }
142
143 temp_packet.at = 0;
144 append_data(&temp_packet, 32, NULL);
145
146 if (fgets(temp_packet.buffer, 33, pipe) == NULL) {
147 fprintf(stderr, "server: failed to read digest\n");
148 exit(1);
149 }
150 if (strlen(temp_packet.buffer) != 32) {
151 fprintf(stderr, "server: digest was not 32 chars?? [%s]\n",
152 temp_packet.buffer);
153 exit(1);
154 }
155
156 fclose(pipe);
157
158 return temp_packet.buffer;
159 }
160
161 void packet_to_prompt(pamc_bp_t *prompt_p, uint8_t control,
162 struct internal_packet *packet)
163 {
164 PAM_BP_RENEW(prompt_p, control, packet->at);
165 PAM_BP_FILL(*prompt_p, 0, packet->at, packet->buffer);
166 packet->at = 0;
167 }
168
169 void prompt_to_packet(pamc_bp_t prompt, struct internal_packet *packet)
170 {
171 int data_length;
172
173 data_length = PAM_BP_LENGTH(prompt);
174 packet->at = 0;
175 append_data(packet, data_length, NULL);
176
177 PAM_BP_EXTRACT(prompt, 0, data_length, packet->buffer);
178
179 fprintf(stderr, "server received[%d]: {%d|0x%.2x|%s}\n",
180 data_length,
181 PAM_BP_SIZE(prompt), PAM_BP_RCONTROL(prompt),
182 PAM_BP_RDATA(prompt));
183 }
184
185 int main(int argc, char **argv)
186 {
187 pamc_handle_t pch;
188 pamc_bp_t prompt = NULL;
189 struct internal_packet packet_data, *packet;
190 char *temp_string, *secret, *user, *a_cookie, *seqid, *digest;
191 const char *cookie = "123451234512345";
192 int retval;
193
194 packet = &packet_data;
195 packet->length = 0;
196 packet->at = 0;
197 packet->buffer = NULL;
198
199 pch = pamc_start();
200 if (pch == NULL) {
201 fprintf(stderr, "server: unable to get a handle from libpamc\n");
202 exit(1);
203 }
204
205 temp_string = getlogin();
206 if (temp_string == NULL) {
207 fprintf(stderr, "server: who are you?\n");
208 exit(1);
209 }
210 #define DOMAIN "@local.host"
211 user = malloc(1+strlen(temp_string)+strlen(DOMAIN));
212 if (user == NULL) {
213 fprintf(stderr, "server: out of memory for user id\n");
214 exit(1);
215 }
216 sprintf(user, "%s%s", temp_string, DOMAIN);
217
218 append_string(packet, "secret@here/", 0);
219 append_string(packet, user, 0);
220 append_string(packet, "|", 0);
221 append_string(packet, cookie, 0);
222 packet_to_prompt(&prompt, PAM_BPC_SELECT, packet);
223
224 /* get the library to accept the first packet (which should load
225 the secret@here agent) */
226
227 retval = pamc_converse(pch, &prompt);
228 fprintf(stderr, "server: after conversation\n");
229 if (PAM_BP_RCONTROL(prompt) != PAM_BPC_OK) {
230 fprintf(stderr, "server: prompt had unexpected control type: %u\n",
231 PAM_BP_RCONTROL(prompt));
232 exit(1);
233 }
234
235 fprintf(stderr, "server: got a prompt back\n");
236
237 prompt_to_packet(prompt, packet);
238
239 temp_string = strtok(packet->buffer, "|");
240 if (temp_string == NULL) {
241 fprintf(stderr, "server: prompt does not contain anything");
242 exit(1);
243 }
244 seqid = strdup(temp_string);
245 if (seqid == NULL) {
246 fprintf(stderr, "server: unable to store sequence id\n");
247 }
248
249 temp_string = strtok(NULL, "|");
250 if (temp_string == NULL) {
251 fprintf(stderr, "server: no cookie from agent\n");
252 exit(1);
253 }
254 a_cookie = strdup(temp_string);
255 if (a_cookie == NULL) {
256 fprintf(stderr, "server: no memory to store agent cookie\n");
257 exit(1);
258 }
259
260 fprintf(stderr, "server: agent responded with {%s|%s}\n", seqid, a_cookie);
261 secret = identify_secret(user);
262 fprintf(stderr, "server: secret=%s\n", secret);
263
264 /* now, we construct the response */
265 packet->at = 0;
266 append_string(packet, a_cookie, 0);
267 append_string(packet, "|", 0);
268 append_string(packet, cookie, 0);
269 append_string(packet, "|", 0);
270 append_string(packet, secret, 0);
271
272 fprintf(stderr, "server: get digest of %s\n", packet->buffer);
273
274 digest = create_digest(packet->at, packet->buffer);
275
276 fprintf(stderr, "server: secret=%s, digest=%s\n", secret, digest);
277
278 packet->at = 0;
279 append_string(packet, seqid, 0);
280 append_string(packet, "|", 0);
281 append_string(packet, digest, 0);
282 packet_to_prompt(&prompt, PAM_BPC_OK, packet);
283
284 retval = pamc_converse(pch, &prompt);
285 fprintf(stderr, "server: after 2nd conversation\n");
286 if (PAM_BP_RCONTROL(prompt) != PAM_BPC_DONE) {
287 fprintf(stderr, "server: 2nd prompt had unexpected control type: %u\n",
288 PAM_BP_RCONTROL(prompt));
289 exit(1);
290 }
291
292 prompt_to_packet(prompt, packet);
293 PAM_BP_RENEW(&prompt, 0, 0);
294
295 temp_string = strtok(packet->buffer, "|");
296 if (temp_string == NULL) {
297 fprintf(stderr, "no digest from agent\n");
298 exit(1);
299 }
300 temp_string = strdup(temp_string);
301
302 packet->at = 0;
303 append_string(packet, secret, 0);
304 append_string(packet, "|", 0);
305 append_string(packet, cookie, 0);
306 append_string(packet, "|", 0);
307 append_string(packet, a_cookie, 0);
308
309 fprintf(stderr, "server: get digest of %s\n", packet->buffer);
310
311 digest = create_digest(packet->at, packet->buffer);
312
313 fprintf(stderr, "server: digest=%s\n", digest);
314
315 if (strcmp(digest, temp_string)) {
316 fprintf(stderr, "server: agent doesn't know the secret\n");
317 fprintf(stderr, "server: agent says: [%s]\n"
318 "server: server says: [%s]\n", temp_string, digest);
319 exit(1);
320 } else {
321 fprintf(stderr, "server: agent seems to know the secret\n");
322
323 packet->at = 0;
324 append_string(packet, cookie, 0);
325 append_string(packet, "|", 0);
326 append_string(packet, secret, 0);
327 append_string(packet, "|", 0);
328 append_string(packet, a_cookie, 0);
329
330 digest = create_digest(packet->at, packet->buffer);
331
332 fprintf(stderr, "server: putenv(\"AUTH_SESSION_TICKET=%s\")\n",
333 digest);
334 }
335
336
337 retval = pamc_end(&pch);
338
339 fprintf(stderr, "server: agent(s) were %shappy to terminate\n",
340 retval == PAM_BPC_TRUE ? "":"un");
341
342 exit(!retval);
343 }