Age Owner Branch data TLA Line data Source code
1 : : /*-------------------------------------------------------------------------
2 : : *
3 : : * auth-scram.c
4 : : * Server-side implementation of the SASL SCRAM-SHA-256 mechanism.
5 : : *
6 : : * See the following RFCs for more details:
7 : : * - RFC 5802: https://tools.ietf.org/html/rfc5802
8 : : * - RFC 5803: https://tools.ietf.org/html/rfc5803
9 : : * - RFC 7677: https://tools.ietf.org/html/rfc7677
10 : : *
11 : : * Here are some differences:
12 : : *
13 : : * - Username from the authentication exchange is not used. The client
14 : : * should send an empty string as the username.
15 : : *
16 : : * - If the password isn't valid UTF-8, or contains characters prohibited
17 : : * by the SASLprep profile, we skip the SASLprep pre-processing and use
18 : : * the raw bytes in calculating the hash.
19 : : *
20 : : * - If channel binding is used, the channel binding type is always
21 : : * "tls-server-end-point". The spec says the default is "tls-unique"
22 : : * (RFC 5802, section 6.1. Default Channel Binding), but there are some
23 : : * problems with that. Firstly, not all SSL libraries provide an API to
24 : : * get the TLS Finished message, required to use "tls-unique". Secondly,
25 : : * "tls-unique" is not specified for TLS v1.3, and as of this writing,
26 : : * it's not clear if there will be a replacement. We could support both
27 : : * "tls-server-end-point" and "tls-unique", but for our use case,
28 : : * "tls-unique" doesn't really have any advantages. The main advantage
29 : : * of "tls-unique" would be that it works even if the server doesn't
30 : : * have a certificate, but PostgreSQL requires a server certificate
31 : : * whenever SSL is used, anyway.
32 : : *
33 : : *
34 : : * The password stored in pg_authid consists of the iteration count, salt,
35 : : * StoredKey and ServerKey.
36 : : *
37 : : * SASLprep usage
38 : : * --------------
39 : : *
40 : : * One notable difference to the SCRAM specification is that while the
41 : : * specification dictates that the password is in UTF-8, and prohibits
42 : : * certain characters, we are more lenient. If the password isn't a valid
43 : : * UTF-8 string, or contains prohibited characters, the raw bytes are used
44 : : * to calculate the hash instead, without SASLprep processing. This is
45 : : * because PostgreSQL supports other encodings too, and the encoding being
46 : : * used during authentication is undefined (client_encoding isn't set until
47 : : * after authentication). In effect, we try to interpret the password as
48 : : * UTF-8 and apply SASLprep processing, but if it looks invalid, we assume
49 : : * that it's in some other encoding.
50 : : *
51 : : * In the worst case, we misinterpret a password that's in a different
52 : : * encoding as being Unicode, because it happens to consists entirely of
53 : : * valid UTF-8 bytes, and we apply Unicode normalization to it. As long
54 : : * as we do that consistently, that will not lead to failed logins.
55 : : * Fortunately, the UTF-8 byte sequences that are ignored by SASLprep
56 : : * don't correspond to any commonly used characters in any of the other
57 : : * supported encodings, so it should not lead to any significant loss in
58 : : * entropy, even if the normalization is incorrectly applied to a
59 : : * non-UTF-8 password.
60 : : *
61 : : * Error handling
62 : : * --------------
63 : : *
64 : : * Don't reveal user information to an unauthenticated client. We don't
65 : : * want an attacker to be able to probe whether a particular username is
66 : : * valid. In SCRAM, the server has to read the salt and iteration count
67 : : * from the user's stored secret, and send it to the client. To avoid
68 : : * revealing whether a user exists, when the client tries to authenticate
69 : : * with a username that doesn't exist, or doesn't have a valid SCRAM
70 : : * secret in pg_authid, we create a fake salt and iteration count
71 : : * on-the-fly, and proceed with the authentication with that. In the end,
72 : : * we'll reject the attempt, as if an incorrect password was given. When
73 : : * we are performing a "mock" authentication, the 'doomed' flag in
74 : : * scram_state is set.
75 : : *
76 : : * In the error messages, avoid printing strings from the client, unless
77 : : * you check that they are pure ASCII. We don't want an unauthenticated
78 : : * attacker to be able to spam the logs with characters that are not valid
79 : : * to the encoding being used, whatever that is. We cannot avoid that in
80 : : * general, after logging in, but let's do what we can here.
81 : : *
82 : : *
83 : : * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group
84 : : * Portions Copyright (c) 1994, Regents of the University of California
85 : : *
86 : : * src/backend/libpq/auth-scram.c
87 : : *
88 : : *-------------------------------------------------------------------------
89 : : */
90 : : #include "postgres.h"
91 : :
92 : : #include <unistd.h>
93 : :
94 : : #include "access/xlog.h"
95 : : #include "catalog/pg_control.h"
96 : : #include "common/base64.h"
97 : : #include "common/hmac.h"
98 : : #include "common/saslprep.h"
99 : : #include "common/scram-common.h"
100 : : #include "common/sha2.h"
101 : : #include "libpq/crypt.h"
102 : : #include "libpq/sasl.h"
103 : : #include "libpq/scram.h"
104 : : #include "miscadmin.h"
105 : :
106 : : static void scram_get_mechanisms(Port *port, StringInfo buf);
107 : : static void *scram_init(Port *port, const char *selected_mech,
108 : : const char *shadow_pass);
109 : : static int scram_exchange(void *opaq, const char *input, int inputlen,
110 : : char **output, int *outputlen,
111 : : const char **logdetail);
112 : :
113 : : /* Mechanism declaration */
114 : : const pg_be_sasl_mech pg_be_scram_mech = {
115 : : scram_get_mechanisms,
116 : : scram_init,
117 : : scram_exchange,
118 : :
119 : : PG_MAX_SASL_MESSAGE_LENGTH
120 : : };
121 : :
122 : : /*
123 : : * Status data for a SCRAM authentication exchange. This should be kept
124 : : * internal to this file.
125 : : */
126 : : typedef enum
127 : : {
128 : : SCRAM_AUTH_INIT,
129 : : SCRAM_AUTH_SALT_SENT,
130 : : SCRAM_AUTH_FINISHED,
131 : : } scram_state_enum;
132 : :
133 : : typedef struct
134 : : {
135 : : scram_state_enum state;
136 : :
137 : : const char *username; /* username from startup packet */
138 : :
139 : : Port *port;
140 : : bool channel_binding_in_use;
141 : :
142 : : /* State data depending on the hash type */
143 : : pg_cryptohash_type hash_type;
144 : : int key_length;
145 : :
146 : : int iterations;
147 : : char *salt; /* base64-encoded */
148 : : uint8 ClientKey[SCRAM_MAX_KEY_LEN];
149 : : uint8 StoredKey[SCRAM_MAX_KEY_LEN];
150 : : uint8 ServerKey[SCRAM_MAX_KEY_LEN];
151 : :
152 : : /* Fields of the first message from client */
153 : : char cbind_flag;
154 : : char *client_first_message_bare;
155 : : char *client_username;
156 : : char *client_nonce;
157 : :
158 : : /* Fields from the last message from client */
159 : : char *client_final_message_without_proof;
160 : : char *client_final_nonce;
161 : : uint8 ClientProof[SCRAM_MAX_KEY_LEN];
162 : :
163 : : /* Fields generated in the server */
164 : : char *server_first_message;
165 : : char *server_nonce;
166 : :
167 : : /*
168 : : * If something goes wrong during the authentication, or we are performing
169 : : * a "mock" authentication (see comments at top of file), the 'doomed'
170 : : * flag is set. A reason for the failure, for the server log, is put in
171 : : * 'logdetail'.
172 : : */
173 : : bool doomed;
174 : : char *logdetail;
175 : : } scram_state;
176 : :
177 : : static void read_client_first_message(scram_state *state, const char *input);
178 : : static void read_client_final_message(scram_state *state, const char *input);
179 : : static char *build_server_first_message(scram_state *state);
180 : : static char *build_server_final_message(scram_state *state);
181 : : static bool verify_client_proof(scram_state *state);
182 : : static bool verify_final_nonce(scram_state *state);
183 : : static void mock_scram_secret(const char *username, pg_cryptohash_type *hash_type,
184 : : int *iterations, int *key_length, char **salt,
185 : : uint8 *stored_key, uint8 *server_key);
186 : : static bool is_scram_printable(char *p);
187 : : static char *sanitize_char(char c);
188 : : static char *sanitize_str(const char *s);
189 : : static uint8 *scram_mock_salt(const char *username,
190 : : pg_cryptohash_type hash_type,
191 : : int key_length);
192 : :
193 : : /*
194 : : * The number of iterations to use when generating new secrets.
195 : : */
196 : : int scram_sha_256_iterations = SCRAM_SHA_256_DEFAULT_ITERATIONS;
197 : :
198 : : /*
199 : : * Get a list of SASL mechanisms that this module supports.
200 : : *
201 : : * For the convenience of building the FE/BE packet that lists the
202 : : * mechanisms, the names are appended to the given StringInfo buffer,
203 : : * separated by '\0' bytes.
204 : : */
205 : : static void
1522 michael@paquier.xyz 206 :CBC 69 : scram_get_mechanisms(Port *port, StringInfo buf)
207 : : {
208 : : /*
209 : : * Advertise the mechanisms in decreasing order of importance. So the
210 : : * channel-binding variants go first, if they are supported. Channel
211 : : * binding is only supported with SSL.
212 : : */
213 : : #ifdef USE_SSL
2589 heikki.linnakangas@i 214 [ + + ]: 69 : if (port->ssl_in_use)
215 : : {
216 : 6 : appendStringInfoString(buf, SCRAM_SHA_256_PLUS_NAME);
217 : 6 : appendStringInfoChar(buf, '\0');
218 : : }
219 : : #endif
220 : 69 : appendStringInfoString(buf, SCRAM_SHA_256_NAME);
221 : 69 : appendStringInfoChar(buf, '\0');
222 : 69 : }
223 : :
224 : : /*
225 : : * Initialize a new SCRAM authentication exchange status tracker. This
226 : : * needs to be called before doing any exchange. It will be filled later
227 : : * after the beginning of the exchange with authentication information.
228 : : *
229 : : * 'selected_mech' identifies the SASL mechanism that the client selected.
230 : : * It should be one of the mechanisms that we support, as returned by
231 : : * scram_get_mechanisms().
232 : : *
233 : : * 'shadow_pass' is the role's stored secret, from pg_authid.rolpassword.
234 : : * The username was provided by the client in the startup message, and is
235 : : * available in port->user_name. If 'shadow_pass' is NULL, we still perform
236 : : * an authentication exchange, but it will fail, as if an incorrect password
237 : : * was given.
238 : : */
239 : : static void *
1522 michael@paquier.xyz 240 : 58 : scram_init(Port *port, const char *selected_mech, const char *shadow_pass)
241 : : {
242 : : scram_state *state;
243 : : bool got_secret;
244 : :
3105 heikki.linnakangas@i 245 : 58 : state = (scram_state *) palloc0(sizeof(scram_state));
2802 peter_e@gmx.net 246 : 58 : state->port = port;
3105 heikki.linnakangas@i 247 : 58 : state->state = SCRAM_AUTH_INIT;
248 : :
249 : : /*
250 : : * Parse the selected mechanism.
251 : : *
252 : : * Note that if we don't support channel binding, or if we're not using
253 : : * SSL at all, we would not have advertised the PLUS variant in the first
254 : : * place. If the client nevertheless tries to select it, it's a protocol
255 : : * violation like selecting any other SASL mechanism we don't support.
256 : : */
257 : : #ifdef USE_SSL
2589 258 [ + + + - ]: 58 : if (strcmp(selected_mech, SCRAM_SHA_256_PLUS_NAME) == 0 && port->ssl_in_use)
259 : 4 : state->channel_binding_in_use = true;
260 : : else
261 : : #endif
262 [ + - ]: 54 : if (strcmp(selected_mech, SCRAM_SHA_256_NAME) == 0)
263 : 54 : state->channel_binding_in_use = false;
264 : : else
2589 heikki.linnakangas@i 265 [ # # ]:UBC 0 : ereport(ERROR,
266 : : (errcode(ERRCODE_PROTOCOL_VIOLATION),
267 : : errmsg("client selected an invalid SASL authentication mechanism")));
268 : :
269 : : /*
270 : : * Parse the stored secret.
271 : : */
3088 heikki.linnakangas@i 272 [ + - ]:CBC 58 : if (shadow_pass)
273 : : {
274 : 58 : int password_type = get_password_type(shadow_pass);
275 : :
3063 276 [ + + ]: 58 : if (password_type == PASSWORD_TYPE_SCRAM_SHA_256)
277 : : {
991 michael@paquier.xyz 278 [ + - ]: 57 : if (parse_scram_secret(shadow_pass, &state->iterations,
279 : : &state->hash_type, &state->key_length,
280 : : &state->salt,
281 : 57 : state->StoredKey,
282 : 57 : state->ServerKey))
2156 peter@eisentraut.org 283 : 57 : got_secret = true;
284 : : else
285 : : {
286 : : /*
287 : : * The password looked like a SCRAM secret, but could not be
288 : : * parsed.
289 : : */
3012 heikki.linnakangas@i 290 [ # # ]:UBC 0 : ereport(LOG,
291 : : (errmsg("invalid SCRAM secret for user \"%s\"",
292 : : state->port->user_name)));
2156 peter@eisentraut.org 293 : 0 : got_secret = false;
294 : : }
295 : : }
296 : : else
297 : : {
298 : : /*
299 : : * The user doesn't have SCRAM secret. (You cannot do SCRAM
300 : : * authentication with an MD5 hash.)
301 : : */
2156 peter@eisentraut.org 302 :CBC 2 : state->logdetail = psprintf(_("User \"%s\" does not have a valid SCRAM secret."),
2802 peter_e@gmx.net 303 : 1 : state->port->user_name);
2156 peter@eisentraut.org 304 : 1 : got_secret = false;
305 : : }
306 : : }
307 : : else
308 : : {
309 : : /*
310 : : * The caller requested us to perform a dummy authentication. This is
311 : : * considered normal, since the caller requested it, so don't set log
312 : : * detail.
313 : : */
2156 peter@eisentraut.org 314 :UBC 0 : got_secret = false;
315 : : }
316 : :
317 : : /*
318 : : * If the user did not have a valid SCRAM secret, we still go through the
319 : : * motions with a mock one, and fail as if the client supplied an
320 : : * incorrect password. This is to avoid revealing information to an
321 : : * attacker.
322 : : */
2156 peter@eisentraut.org 323 [ + + ]:CBC 58 : if (!got_secret)
324 : : {
991 michael@paquier.xyz 325 : 1 : mock_scram_secret(state->port->user_name, &state->hash_type,
326 : : &state->iterations, &state->key_length,
327 : : &state->salt,
328 : 1 : state->StoredKey, state->ServerKey);
3088 heikki.linnakangas@i 329 : 1 : state->doomed = true;
330 : : }
331 : :
3105 332 : 58 : return state;
333 : : }
334 : :
335 : : /*
336 : : * Continue a SCRAM authentication exchange.
337 : : *
338 : : * 'input' is the SCRAM payload sent by the client. On the first call,
339 : : * 'input' contains the "Initial Client Response" that the client sent as
340 : : * part of the SASLInitialResponse message, or NULL if no Initial Client
341 : : * Response was given. (The SASL specification distinguishes between an
342 : : * empty response and non-existing one.) On subsequent calls, 'input'
343 : : * cannot be NULL. For convenience in this function, the caller must
344 : : * ensure that there is a null terminator at input[inputlen].
345 : : *
346 : : * The next message to send to client is saved in 'output', for a length
347 : : * of 'outputlen'. In the case of an error, optionally store a palloc'd
348 : : * string at *logdetail that will be sent to the postmaster log (but not
349 : : * the client).
350 : : */
351 : : static int
1522 michael@paquier.xyz 352 : 116 : scram_exchange(void *opaq, const char *input, int inputlen,
353 : : char **output, int *outputlen, const char **logdetail)
354 : : {
3105 heikki.linnakangas@i 355 : 116 : scram_state *state = (scram_state *) opaq;
356 : : int result;
357 : :
358 : 116 : *output = NULL;
359 : :
360 : : /*
361 : : * If the client didn't include an "Initial Client Response" in the
362 : : * SASLInitialResponse message, send an empty challenge, to which the
363 : : * client will respond with the same data that usually comes in the
364 : : * Initial Client Response.
365 : : */
3068 366 [ - + ]: 116 : if (input == NULL)
367 : : {
3068 heikki.linnakangas@i 368 [ # # ]:UBC 0 : Assert(state->state == SCRAM_AUTH_INIT);
369 : :
370 : 0 : *output = pstrdup("");
371 : 0 : *outputlen = 0;
1522 michael@paquier.xyz 372 : 0 : return PG_SASL_EXCHANGE_CONTINUE;
373 : : }
374 : :
375 : : /*
376 : : * Check that the input length agrees with the string length of the input.
377 : : * We can ignore inputlen after this.
378 : : */
3105 heikki.linnakangas@i 379 [ - + ]:CBC 116 : if (inputlen == 0)
3105 heikki.linnakangas@i 380 [ # # ]:UBC 0 : ereport(ERROR,
381 : : (errcode(ERRCODE_PROTOCOL_VIOLATION),
382 : : errmsg("malformed SCRAM message"),
383 : : errdetail("The message is empty.")));
3105 heikki.linnakangas@i 384 [ - + ]:CBC 116 : if (inputlen != strlen(input))
3105 heikki.linnakangas@i 385 [ # # ]:UBC 0 : ereport(ERROR,
386 : : (errcode(ERRCODE_PROTOCOL_VIOLATION),
387 : : errmsg("malformed SCRAM message"),
388 : : errdetail("Message length does not match input length.")));
389 : :
3105 heikki.linnakangas@i 390 [ + + - ]:CBC 116 : switch (state->state)
391 : : {
392 : 58 : case SCRAM_AUTH_INIT:
393 : :
394 : : /*
395 : : * Initialization phase. Receive the first message from client
396 : : * and be sure that it parsed correctly. Then send the challenge
397 : : * to the client.
398 : : */
399 : 58 : read_client_first_message(state, input);
400 : :
401 : : /* prepare message to send challenge */
402 : 58 : *output = build_server_first_message(state);
403 : :
404 : 58 : state->state = SCRAM_AUTH_SALT_SENT;
1522 michael@paquier.xyz 405 : 58 : result = PG_SASL_EXCHANGE_CONTINUE;
3105 heikki.linnakangas@i 406 : 58 : break;
407 : :
408 : 58 : case SCRAM_AUTH_SALT_SENT:
409 : :
410 : : /*
411 : : * Final phase for the server. Receive the response to the
412 : : * challenge previously sent, verify, and let the client know that
413 : : * everything went well (or not).
414 : : */
415 : 58 : read_client_final_message(state, input);
416 : :
417 [ - + ]: 58 : if (!verify_final_nonce(state))
3105 heikki.linnakangas@i 418 [ # # ]:UBC 0 : ereport(ERROR,
419 : : (errcode(ERRCODE_PROTOCOL_VIOLATION),
420 : : errmsg("invalid SCRAM response"),
421 : : errdetail("Nonce does not match.")));
422 : :
423 : : /*
424 : : * Now check the final nonce and the client proof.
425 : : *
426 : : * If we performed a "mock" authentication that we knew would fail
427 : : * from the get go, this is where we fail.
428 : : *
429 : : * The SCRAM specification includes an error code,
430 : : * "invalid-proof", for authentication failure, but it also allows
431 : : * erroring out in an application-specific way. We choose to do
432 : : * the latter, so that the error message for invalid password is
433 : : * the same for all authentication methods. The caller will call
434 : : * ereport(), when we return PG_SASL_EXCHANGE_FAILURE with no
435 : : * output.
436 : : *
437 : : * NB: the order of these checks is intentional. We calculate the
438 : : * client proof even in a mock authentication, even though it's
439 : : * bound to fail, to thwart timing attacks to determine if a role
440 : : * with the given name exists or not.
441 : : */
3105 heikki.linnakangas@i 442 [ + + - + ]:CBC 58 : if (!verify_client_proof(state) || state->doomed)
443 : : {
1522 michael@paquier.xyz 444 : 5 : result = PG_SASL_EXCHANGE_FAILURE;
3105 heikki.linnakangas@i 445 : 5 : break;
446 : : }
447 : :
448 : : /* Build final message for client */
449 : 53 : *output = build_server_final_message(state);
450 : :
451 : : /* Success! */
1522 michael@paquier.xyz 452 : 53 : result = PG_SASL_EXCHANGE_SUCCESS;
3105 heikki.linnakangas@i 453 : 53 : state->state = SCRAM_AUTH_FINISHED;
454 : 53 : break;
455 : :
3105 heikki.linnakangas@i 456 :UBC 0 : default:
457 [ # # ]: 0 : elog(ERROR, "invalid SCRAM exchange state");
458 : : result = PG_SASL_EXCHANGE_FAILURE;
459 : : }
460 : :
1522 michael@paquier.xyz 461 [ + + + + :CBC 116 : if (result == PG_SASL_EXCHANGE_FAILURE && state->logdetail && logdetail)
+ - ]
3105 heikki.linnakangas@i 462 : 1 : *logdetail = state->logdetail;
463 : :
464 [ + + ]: 116 : if (*output)
465 : 111 : *outputlen = strlen(*output);
466 : :
234 peter@eisentraut.org 467 [ + + + - ]: 116 : if (result == PG_SASL_EXCHANGE_SUCCESS && state->state == SCRAM_AUTH_FINISHED)
468 : : {
469 : 53 : memcpy(MyProcPort->scram_ClientKey, state->ClientKey, sizeof(MyProcPort->scram_ClientKey));
470 : 53 : memcpy(MyProcPort->scram_ServerKey, state->ServerKey, sizeof(MyProcPort->scram_ServerKey));
471 : 53 : MyProcPort->has_scram_keys = true;
472 : : }
473 : :
3105 heikki.linnakangas@i 474 : 116 : return result;
475 : : }
476 : :
477 : : /*
478 : : * Construct a SCRAM secret, for storing in pg_authid.rolpassword.
479 : : *
480 : : * The result is palloc'd, so caller is responsible for freeing it.
481 : : */
482 : : char *
2156 peter@eisentraut.org 483 : 51 : pg_be_scram_build_secret(const char *password)
484 : : {
485 : : char *prep_password;
486 : : pg_saslprep_rc rc;
487 : : uint8 saltbuf[SCRAM_DEFAULT_SALT_LEN];
488 : : char *result;
1332 michael@paquier.xyz 489 : 51 : const char *errstr = NULL;
490 : :
491 : : /*
492 : : * Normalize the password with SASLprep. If that doesn't work, because
493 : : * the password isn't valid UTF-8 or contains prohibited characters, just
494 : : * proceed with the original password. (See comments at top of file.)
495 : : */
3074 heikki.linnakangas@i 496 : 51 : rc = pg_saslprep(password, &prep_password);
497 [ + + ]: 51 : if (rc == SASLPREP_SUCCESS)
498 : 50 : password = (const char *) prep_password;
499 : :
500 : : /* Generate random salt */
2440 michael@paquier.xyz 501 [ - + ]: 51 : if (!pg_strong_random(saltbuf, SCRAM_DEFAULT_SALT_LEN))
3012 heikki.linnakangas@i 502 [ # # ]:UBC 0 : ereport(ERROR,
503 : : (errcode(ERRCODE_INTERNAL_ERROR),
504 : : errmsg("could not generate random salt")));
505 : :
991 michael@paquier.xyz 506 :CBC 51 : result = scram_build_secret(PG_SHA256, SCRAM_SHA_256_KEY_LEN,
507 : : saltbuf, SCRAM_DEFAULT_SALT_LEN,
508 : : scram_sha_256_iterations, password,
509 : : &errstr);
510 : :
3074 heikki.linnakangas@i 511 [ + + ]: 51 : if (prep_password)
512 : 50 : pfree(prep_password);
513 : :
3060 514 : 51 : return result;
515 : : }
516 : :
517 : : /*
518 : : * Verify a plaintext password against a SCRAM secret. This is used when
519 : : * performing plaintext password authentication for a user that has a SCRAM
520 : : * secret stored in pg_authid.
521 : : */
522 : : bool
3095 523 : 27 : scram_verify_plain_password(const char *username, const char *password,
524 : : const char *secret)
525 : : {
526 : : char *encoded_salt;
527 : : uint8 *salt;
528 : : int saltlen;
529 : : int iterations;
991 michael@paquier.xyz 530 : 27 : int key_length = 0;
531 : : pg_cryptohash_type hash_type;
532 : : uint8 salted_password[SCRAM_MAX_KEY_LEN];
533 : : uint8 stored_key[SCRAM_MAX_KEY_LEN];
534 : : uint8 server_key[SCRAM_MAX_KEY_LEN];
535 : : uint8 computed_key[SCRAM_MAX_KEY_LEN];
536 : : char *prep_password;
537 : : pg_saslprep_rc rc;
1332 538 : 27 : const char *errstr = NULL;
539 : :
991 540 [ - + ]: 27 : if (!parse_scram_secret(secret, &iterations, &hash_type, &key_length,
541 : : &encoded_salt, stored_key, server_key))
542 : : {
543 : : /*
544 : : * The password looked like a SCRAM secret, but could not be parsed.
545 : : */
3012 heikki.linnakangas@i 546 [ # # ]:UBC 0 : ereport(LOG,
547 : : (errmsg("invalid SCRAM secret for user \"%s\"", username)));
3095 548 : 0 : return false;
549 : : }
550 : :
2256 michael@paquier.xyz 551 :CBC 27 : saltlen = pg_b64_dec_len(strlen(encoded_salt));
552 : 27 : salt = palloc(saltlen);
553 : 27 : saltlen = pg_b64_decode(encoded_salt, strlen(encoded_salt), salt,
554 : : saltlen);
555 [ - + ]: 27 : if (saltlen < 0)
556 : : {
3012 heikki.linnakangas@i 557 [ # # ]:UBC 0 : ereport(LOG,
558 : : (errmsg("invalid SCRAM secret for user \"%s\"", username)));
3095 559 : 0 : return false;
560 : : }
561 : :
562 : : /* Normalize the password */
3074 heikki.linnakangas@i 563 :CBC 27 : rc = pg_saslprep(password, &prep_password);
564 [ + - ]: 27 : if (rc == SASLPREP_SUCCESS)
565 : 27 : password = prep_password;
566 : :
567 : : /* Compute Server Key based on the user-supplied plaintext password */
991 michael@paquier.xyz 568 [ + - ]: 27 : if (scram_SaltedPassword(password, hash_type, key_length,
569 : : salt, saltlen, iterations,
1332 570 [ - + ]: 27 : salted_password, &errstr) < 0 ||
991 571 : 27 : scram_ServerKey(salted_password, hash_type, key_length,
572 : : computed_key, &errstr) < 0)
573 : : {
1332 michael@paquier.xyz 574 [ # # ]:UBC 0 : elog(ERROR, "could not compute server key: %s", errstr);
575 : : }
576 : :
3074 heikki.linnakangas@i 577 [ + - ]:CBC 27 : if (prep_password)
578 : 27 : pfree(prep_password);
579 : :
580 : : /*
581 : : * Compare the secret's Server Key with the one computed from the
582 : : * user-supplied password.
583 : : */
991 michael@paquier.xyz 584 : 27 : return memcmp(computed_key, server_key, key_length) == 0;
585 : : }
586 : :
587 : :
588 : : /*
589 : : * Parse and validate format of given SCRAM secret.
590 : : *
591 : : * On success, the iteration count, salt, stored key, and server key are
592 : : * extracted from the secret, and returned to the caller. For 'stored_key'
593 : : * and 'server_key', the caller must pass pre-allocated buffers of size
594 : : * SCRAM_MAX_KEY_LEN. Salt is returned as a base64-encoded, null-terminated
595 : : * string. The buffer for the salt is palloc'd by this function.
596 : : *
597 : : * Returns true if the SCRAM secret has been parsed, and false otherwise.
598 : : */
599 : : bool
600 : 438 : parse_scram_secret(const char *secret, int *iterations,
601 : : pg_cryptohash_type *hash_type, int *key_length,
602 : : char **salt, uint8 *stored_key, uint8 *server_key)
603 : : {
604 : : char *v;
605 : : char *p;
606 : : char *scheme_str;
607 : : char *salt_str;
608 : : char *iterations_str;
609 : : char *storedkey_str;
610 : : char *serverkey_str;
611 : : int decoded_len;
612 : : uint8 *decoded_salt_buf;
613 : : uint8 *decoded_stored_buf;
614 : : uint8 *decoded_server_buf;
615 : :
616 : : /*
617 : : * The secret is of form:
618 : : *
619 : : * SCRAM-SHA-256$<iterations>:<salt>$<storedkey>:<serverkey>
620 : : */
2156 peter@eisentraut.org 621 : 438 : v = pstrdup(secret);
323 622 : 438 : scheme_str = strsep(&v, "$");
623 [ + + ]: 438 : if (v == NULL)
2156 624 : 111 : goto invalid_secret;
323 625 : 327 : iterations_str = strsep(&v, ":");
626 [ + + ]: 327 : if (v == NULL)
2156 627 : 6 : goto invalid_secret;
323 628 : 321 : salt_str = strsep(&v, "$");
629 [ - + ]: 321 : if (v == NULL)
2156 peter@eisentraut.org 630 :UBC 0 : goto invalid_secret;
323 peter@eisentraut.org 631 :CBC 321 : storedkey_str = strsep(&v, ":");
632 [ - + ]: 321 : if (v == NULL)
2156 peter@eisentraut.org 633 :UBC 0 : goto invalid_secret;
411 peter@eisentraut.org 634 :CBC 321 : serverkey_str = v;
635 : :
636 : : /* Parse the fields */
3060 heikki.linnakangas@i 637 [ - + ]: 321 : if (strcmp(scheme_str, "SCRAM-SHA-256") != 0)
2156 peter@eisentraut.org 638 :UBC 0 : goto invalid_secret;
991 michael@paquier.xyz 639 :CBC 321 : *hash_type = PG_SHA256;
640 : 321 : *key_length = SCRAM_SHA_256_KEY_LEN;
641 : :
3105 heikki.linnakangas@i 642 : 321 : errno = 0;
3060 643 : 321 : *iterations = strtol(iterations_str, &p, 10);
3105 644 [ + - - + ]: 321 : if (*p || errno != 0)
2156 peter@eisentraut.org 645 :UBC 0 : goto invalid_secret;
646 : :
647 : : /*
648 : : * Verify that the salt is in Base64-encoded format, by decoding it,
649 : : * although we return the encoded version to the caller.
650 : : */
2256 michael@paquier.xyz 651 :CBC 321 : decoded_len = pg_b64_dec_len(strlen(salt_str));
652 : 321 : decoded_salt_buf = palloc(decoded_len);
2273 653 : 321 : decoded_len = pg_b64_decode(salt_str, strlen(salt_str),
654 : : decoded_salt_buf, decoded_len);
3060 heikki.linnakangas@i 655 [ - + ]: 321 : if (decoded_len < 0)
2156 peter@eisentraut.org 656 :UBC 0 : goto invalid_secret;
3060 heikki.linnakangas@i 657 :CBC 321 : *salt = pstrdup(salt_str);
658 : :
659 : : /*
660 : : * Decode StoredKey and ServerKey.
661 : : */
2256 michael@paquier.xyz 662 : 321 : decoded_len = pg_b64_dec_len(strlen(storedkey_str));
663 : 321 : decoded_stored_buf = palloc(decoded_len);
3060 heikki.linnakangas@i 664 : 321 : decoded_len = pg_b64_decode(storedkey_str, strlen(storedkey_str),
665 : : decoded_stored_buf, decoded_len);
991 michael@paquier.xyz 666 [ + + ]: 321 : if (decoded_len != *key_length)
2156 peter@eisentraut.org 667 : 6 : goto invalid_secret;
991 michael@paquier.xyz 668 : 315 : memcpy(stored_key, decoded_stored_buf, *key_length);
669 : :
2256 670 : 315 : decoded_len = pg_b64_dec_len(strlen(serverkey_str));
671 : 315 : decoded_server_buf = palloc(decoded_len);
3060 heikki.linnakangas@i 672 : 315 : decoded_len = pg_b64_decode(serverkey_str, strlen(serverkey_str),
673 : : decoded_server_buf, decoded_len);
991 michael@paquier.xyz 674 [ + + ]: 315 : if (decoded_len != *key_length)
2156 peter@eisentraut.org 675 : 6 : goto invalid_secret;
991 michael@paquier.xyz 676 : 309 : memcpy(server_key, decoded_server_buf, *key_length);
677 : :
3105 heikki.linnakangas@i 678 : 309 : return true;
679 : :
2156 peter@eisentraut.org 680 : 129 : invalid_secret:
3060 heikki.linnakangas@i 681 : 129 : *salt = NULL;
3105 682 : 129 : return false;
683 : : }
684 : :
685 : : /*
686 : : * Generate plausible SCRAM secret parameters for mock authentication.
687 : : *
688 : : * In a normal authentication, these are extracted from the secret
689 : : * stored in the server. This function generates values that look
690 : : * realistic, for when there is no stored secret, using SCRAM-SHA-256.
691 : : *
692 : : * Like in parse_scram_secret(), for 'stored_key' and 'server_key', the
693 : : * caller must pass pre-allocated buffers of size SCRAM_MAX_KEY_LEN, and
694 : : * the buffer for the salt is palloc'd by this function.
695 : : */
696 : : static void
991 michael@paquier.xyz 697 : 1 : mock_scram_secret(const char *username, pg_cryptohash_type *hash_type,
698 : : int *iterations, int *key_length, char **salt,
699 : : uint8 *stored_key, uint8 *server_key)
700 : : {
701 : : uint8 *raw_salt;
702 : : char *encoded_salt;
703 : : int encoded_len;
704 : :
705 : : /* Enforce the use of SHA-256, which would be realistic enough */
706 : 1 : *hash_type = PG_SHA256;
707 : 1 : *key_length = SCRAM_SHA_256_KEY_LEN;
708 : :
709 : : /*
710 : : * Generate deterministic salt.
711 : : *
712 : : * Note that we cannot reveal any information to an attacker here so the
713 : : * error messages need to remain generic. This should never fail anyway
714 : : * as the salt generated for mock authentication uses the cluster's nonce
715 : : * value.
716 : : */
717 : 1 : raw_salt = scram_mock_salt(username, *hash_type, *key_length);
1739 718 [ - + ]: 1 : if (raw_salt == NULL)
1739 michael@paquier.xyz 719 [ # # ]:UBC 0 : elog(ERROR, "could not encode salt");
720 : :
2256 michael@paquier.xyz 721 :CBC 1 : encoded_len = pg_b64_enc_len(SCRAM_DEFAULT_SALT_LEN);
722 : : /* don't forget the zero-terminator */
723 : 1 : encoded_salt = (char *) palloc(encoded_len + 1);
724 : 1 : encoded_len = pg_b64_encode(raw_salt, SCRAM_DEFAULT_SALT_LEN, encoded_salt,
725 : : encoded_len);
726 : :
727 [ - + ]: 1 : if (encoded_len < 0)
2256 michael@paquier.xyz 728 [ # # ]:UBC 0 : elog(ERROR, "could not encode salt");
3105 heikki.linnakangas@i 729 :CBC 1 : encoded_salt[encoded_len] = '\0';
730 : :
731 : 1 : *salt = encoded_salt;
894 dgustafsson@postgres 732 : 1 : *iterations = SCRAM_SHA_256_DEFAULT_ITERATIONS;
733 : :
734 : : /* StoredKey and ServerKey are not used in a doomed authentication */
991 michael@paquier.xyz 735 : 1 : memset(stored_key, 0, SCRAM_MAX_KEY_LEN);
736 : 1 : memset(server_key, 0, SCRAM_MAX_KEY_LEN);
3105 heikki.linnakangas@i 737 : 1 : }
738 : :
739 : : /*
740 : : * Read the value in a given SCRAM exchange message for given attribute.
741 : : */
742 : : static char *
743 : 236 : read_attr_value(char **input, char attr)
744 : : {
745 : 236 : char *begin = *input;
746 : : char *end;
747 : :
748 [ - + ]: 236 : if (*begin != attr)
3105 heikki.linnakangas@i 749 [ # # ]:UBC 0 : ereport(ERROR,
750 : : (errcode(ERRCODE_PROTOCOL_VIOLATION),
751 : : errmsg("malformed SCRAM message"),
752 : : errdetail("Expected attribute \"%c\" but found \"%s\".",
753 : : attr, sanitize_char(*begin))));
3105 heikki.linnakangas@i 754 :CBC 236 : begin++;
755 : :
756 [ - + ]: 236 : if (*begin != '=')
3105 heikki.linnakangas@i 757 [ # # ]:UBC 0 : ereport(ERROR,
758 : : (errcode(ERRCODE_PROTOCOL_VIOLATION),
759 : : errmsg("malformed SCRAM message"),
760 : : errdetail("Expected character \"=\" for attribute \"%c\".", attr)));
3105 heikki.linnakangas@i 761 :CBC 236 : begin++;
762 : :
763 : 236 : end = begin;
764 [ + + + + ]: 5012 : while (*end && *end != ',')
765 : 4776 : end++;
766 : :
767 [ + + ]: 236 : if (*end)
768 : : {
769 : 178 : *end = '\0';
770 : 178 : *input = end + 1;
771 : : }
772 : : else
773 : 58 : *input = end;
774 : :
775 : 236 : return begin;
776 : : }
777 : :
778 : : static bool
779 : 58 : is_scram_printable(char *p)
780 : : {
781 : : /*------
782 : : * Printable characters, as defined by SCRAM spec: (RFC 5802)
783 : : *
784 : : * printable = %x21-2B / %x2D-7E
785 : : * ;; Printable ASCII except ",".
786 : : * ;; Note that any "printable" is also
787 : : * ;; a valid "value".
788 : : *------
789 : : */
790 [ + + ]: 1450 : for (; *p; p++)
791 : : {
792 [ + - + - : 1392 : if (*p < 0x21 || *p > 0x7E || *p == 0x2C /* comma */ )
- + ]
3105 heikki.linnakangas@i 793 :UBC 0 : return false;
794 : : }
3105 heikki.linnakangas@i 795 :CBC 58 : return true;
796 : : }
797 : :
798 : : /*
799 : : * Convert an arbitrary byte to printable form. For error messages.
800 : : *
801 : : * If it's a printable ASCII character, print it as a single character.
802 : : * otherwise, print it in hex.
803 : : *
804 : : * The returned pointer points to a static buffer.
805 : : */
806 : : static char *
3105 heikki.linnakangas@i 807 :UBC 0 : sanitize_char(char c)
808 : : {
809 : : static char buf[5];
810 : :
811 [ # # # # ]: 0 : if (c >= 0x21 && c <= 0x7E)
812 : 0 : snprintf(buf, sizeof(buf), "'%c'", c);
813 : : else
3046 814 : 0 : snprintf(buf, sizeof(buf), "0x%02x", (unsigned char) c);
3105 815 : 0 : return buf;
816 : : }
817 : :
818 : : /*
819 : : * Convert an arbitrary string to printable form, for error messages.
820 : : *
821 : : * Anything that's not a printable ASCII character is replaced with
822 : : * '?', and the string is truncated at 30 characters.
823 : : *
824 : : * The returned pointer points to a static buffer.
825 : : */
826 : : static char *
2589 827 : 0 : sanitize_str(const char *s)
828 : : {
829 : : static char buf[30 + 1];
830 : : int i;
831 : :
832 [ # # ]: 0 : for (i = 0; i < sizeof(buf) - 1; i++)
833 : : {
834 : 0 : char c = s[i];
835 : :
836 [ # # ]: 0 : if (c == '\0')
837 : 0 : break;
838 : :
839 [ # # # # ]: 0 : if (c >= 0x21 && c <= 0x7E)
840 : 0 : buf[i] = c;
841 : : else
842 : 0 : buf[i] = '?';
843 : : }
844 : 0 : buf[i] = '\0';
845 : 0 : return buf;
846 : : }
847 : :
848 : : /*
849 : : * Read the next attribute and value in a SCRAM exchange message.
850 : : *
851 : : * The attribute character is set in *attr_p, the attribute value is the
852 : : * return value.
853 : : */
854 : : static char *
3105 heikki.linnakangas@i 855 :CBC 58 : read_any_attr(char **input, char *attr_p)
856 : : {
857 : 58 : char *begin = *input;
858 : : char *end;
859 : 58 : char attr = *begin;
860 : :
2209 peter@eisentraut.org 861 [ - + ]: 58 : if (attr == '\0')
2209 peter@eisentraut.org 862 [ # # ]:UBC 0 : ereport(ERROR,
863 : : (errcode(ERRCODE_PROTOCOL_VIOLATION),
864 : : errmsg("malformed SCRAM message"),
865 : : errdetail("Attribute expected, but found end of string.")));
866 : :
867 : : /*------
868 : : * attr-val = ALPHA "=" value
869 : : * ;; Generic syntax of any attribute sent
870 : : * ;; by server or client
871 : : *------
872 : : */
3105 heikki.linnakangas@i 873 [ + - + - :CBC 58 : if (!((attr >= 'A' && attr <= 'Z') ||
+ - ]
874 [ - + ]: 58 : (attr >= 'a' && attr <= 'z')))
3105 heikki.linnakangas@i 875 [ # # ]:UBC 0 : ereport(ERROR,
876 : : (errcode(ERRCODE_PROTOCOL_VIOLATION),
877 : : errmsg("malformed SCRAM message"),
878 : : errdetail("Attribute expected, but found invalid character \"%s\".",
879 : : sanitize_char(attr))));
3105 heikki.linnakangas@i 880 [ + - ]:CBC 58 : if (attr_p)
881 : 58 : *attr_p = attr;
882 : 58 : begin++;
883 : :
884 [ - + ]: 58 : if (*begin != '=')
3105 heikki.linnakangas@i 885 [ # # ]:UBC 0 : ereport(ERROR,
886 : : (errcode(ERRCODE_PROTOCOL_VIOLATION),
887 : : errmsg("malformed SCRAM message"),
888 : : errdetail("Expected character \"=\" for attribute \"%c\".", attr)));
3105 heikki.linnakangas@i 889 :CBC 58 : begin++;
890 : :
891 : 58 : end = begin;
892 [ + + + - ]: 2610 : while (*end && *end != ',')
893 : 2552 : end++;
894 : :
895 [ - + ]: 58 : if (*end)
896 : : {
3105 heikki.linnakangas@i 897 :UBC 0 : *end = '\0';
898 : 0 : *input = end + 1;
899 : : }
900 : : else
3105 heikki.linnakangas@i 901 :CBC 58 : *input = end;
902 : :
903 : 58 : return begin;
904 : : }
905 : :
906 : : /*
907 : : * Read and parse the first message from client in the context of a SCRAM
908 : : * authentication exchange message.
909 : : *
910 : : * At this stage, any errors will be reported directly with ereport(ERROR).
911 : : */
912 : : static void
2396 peter@eisentraut.org 913 : 58 : read_client_first_message(scram_state *state, const char *input)
914 : : {
915 : 58 : char *p = pstrdup(input);
916 : : char *channel_binding_type;
917 : :
918 : :
919 : : /*------
920 : : * The syntax for the client-first-message is: (RFC 5802)
921 : : *
922 : : * saslname = 1*(value-safe-char / "=2C" / "=3D")
923 : : * ;; Conforms to <value>.
924 : : *
925 : : * authzid = "a=" saslname
926 : : * ;; Protocol specific.
927 : : *
928 : : * cb-name = 1*(ALPHA / DIGIT / "." / "-")
929 : : * ;; See RFC 5056, Section 7.
930 : : * ;; E.g., "tls-server-end-point" or
931 : : * ;; "tls-unique".
932 : : *
933 : : * gs2-cbind-flag = ("p=" cb-name) / "n" / "y"
934 : : * ;; "n" -> client doesn't support channel binding.
935 : : * ;; "y" -> client does support channel binding
936 : : * ;; but thinks the server does not.
937 : : * ;; "p" -> client requires channel binding.
938 : : * ;; The selected channel binding follows "p=".
939 : : *
940 : : * gs2-header = gs2-cbind-flag "," [ authzid ] ","
941 : : * ;; GS2 header for SCRAM
942 : : * ;; (the actual GS2 header includes an optional
943 : : * ;; flag to indicate that the GSS mechanism is not
944 : : * ;; "standard", but since SCRAM is "standard", we
945 : : * ;; don't include that flag).
946 : : *
947 : : * username = "n=" saslname
948 : : * ;; Usernames are prepared using SASLprep.
949 : : *
950 : : * reserved-mext = "m=" 1*(value-char)
951 : : * ;; Reserved for signaling mandatory extensions.
952 : : * ;; The exact syntax will be defined in
953 : : * ;; the future.
954 : : *
955 : : * nonce = "r=" c-nonce [s-nonce]
956 : : * ;; Second part provided by server.
957 : : *
958 : : * c-nonce = printable
959 : : *
960 : : * client-first-message-bare =
961 : : * [reserved-mext ","]
962 : : * username "," nonce ["," extensions]
963 : : *
964 : : * client-first-message =
965 : : * gs2-header client-first-message-bare
966 : : *
967 : : * For example:
968 : : * n,,n=user,r=fyko+d2lbbFgONRv9qkxdawL
969 : : *
970 : : * The "n,," in the beginning means that the client doesn't support
971 : : * channel binding, and no authzid is given. "n=user" is the username.
972 : : * However, in PostgreSQL the username is sent in the startup packet, and
973 : : * the username in the SCRAM exchange is ignored. libpq always sends it
974 : : * as an empty string. The last part, "r=fyko+d2lbbFgONRv9qkxdawL" is
975 : : * the client nonce.
976 : : *------
977 : : */
978 : :
979 : : /*
980 : : * Read gs2-cbind-flag. (For details see also RFC 5802 Section 6 "Channel
981 : : * Binding".)
982 : : */
983 : 58 : state->cbind_flag = *p;
984 [ + - + - ]: 58 : switch (*p)
985 : : {
3105 heikki.linnakangas@i 986 : 54 : case 'n':
987 : :
988 : : /*
989 : : * The client does not support channel binding or has simply
990 : : * decided to not use it. In that case just let it go.
991 : : */
2589 992 [ - + ]: 54 : if (state->channel_binding_in_use)
2589 heikki.linnakangas@i 993 [ # # ]:UBC 0 : ereport(ERROR,
994 : : (errcode(ERRCODE_PROTOCOL_VIOLATION),
995 : : errmsg("malformed SCRAM message"),
996 : : errdetail("The client selected SCRAM-SHA-256-PLUS, but the SCRAM message does not include channel binding data.")));
997 : :
2396 peter@eisentraut.org 998 :CBC 54 : p++;
999 [ - + ]: 54 : if (*p != ',')
2849 peter_e@gmx.net 1000 [ # # ]:UBC 0 : ereport(ERROR,
1001 : : (errcode(ERRCODE_PROTOCOL_VIOLATION),
1002 : : errmsg("malformed SCRAM message"),
1003 : : errdetail("Comma expected, but found character \"%s\".",
1004 : : sanitize_char(*p))));
2396 peter@eisentraut.org 1005 :CBC 54 : p++;
3105 heikki.linnakangas@i 1006 : 54 : break;
3105 heikki.linnakangas@i 1007 :UBC 0 : case 'y':
1008 : :
1009 : : /*
1010 : : * The client supports channel binding and thinks that the server
1011 : : * does not. In this case, the server must fail authentication if
1012 : : * it supports channel binding.
1013 : : */
2589 1014 [ # # ]: 0 : if (state->channel_binding_in_use)
1015 [ # # ]: 0 : ereport(ERROR,
1016 : : (errcode(ERRCODE_PROTOCOL_VIOLATION),
1017 : : errmsg("malformed SCRAM message"),
1018 : : errdetail("The client selected SCRAM-SHA-256-PLUS, but the SCRAM message does not include channel binding data.")));
1019 : :
1020 : : #ifdef USE_SSL
2802 peter_e@gmx.net 1021 [ # # ]: 0 : if (state->port->ssl_in_use)
2849 1022 [ # # ]: 0 : ereport(ERROR,
1023 : : (errcode(ERRCODE_INVALID_AUTHORIZATION_SPECIFICATION),
1024 : : errmsg("SCRAM channel binding negotiation error"),
1025 : : errdetail("The client supports SCRAM channel binding but thinks the server does not. "
1026 : : "However, this server does support channel binding.")));
1027 : : #endif
2396 peter@eisentraut.org 1028 : 0 : p++;
1029 [ # # ]: 0 : if (*p != ',')
2849 peter_e@gmx.net 1030 [ # # ]: 0 : ereport(ERROR,
1031 : : (errcode(ERRCODE_PROTOCOL_VIOLATION),
1032 : : errmsg("malformed SCRAM message"),
1033 : : errdetail("Comma expected, but found character \"%s\".",
1034 : : sanitize_char(*p))));
2396 peter@eisentraut.org 1035 : 0 : p++;
3105 heikki.linnakangas@i 1036 : 0 : break;
3105 heikki.linnakangas@i 1037 :CBC 4 : case 'p':
1038 : :
1039 : : /*
1040 : : * The client requires channel binding. Channel binding type
1041 : : * follows, e.g., "p=tls-server-end-point".
1042 : : */
2589 1043 [ - + ]: 4 : if (!state->channel_binding_in_use)
2589 heikki.linnakangas@i 1044 [ # # ]:UBC 0 : ereport(ERROR,
1045 : : (errcode(ERRCODE_PROTOCOL_VIOLATION),
1046 : : errmsg("malformed SCRAM message"),
1047 : : errdetail("The client selected SCRAM-SHA-256 without channel binding, but the SCRAM message includes channel binding data.")));
1048 : :
2396 peter@eisentraut.org 1049 :CBC 4 : channel_binding_type = read_attr_value(&p, 'p');
1050 : :
1051 : : /*
1052 : : * The only channel binding type we support is
1053 : : * tls-server-end-point.
1054 : : */
2589 heikki.linnakangas@i 1055 [ - + ]: 4 : if (strcmp(channel_binding_type, "tls-server-end-point") != 0)
2589 heikki.linnakangas@i 1056 [ # # ]:UBC 0 : ereport(ERROR,
1057 : : (errcode(ERRCODE_PROTOCOL_VIOLATION),
1058 : : errmsg("unsupported SCRAM channel-binding type \"%s\"",
1059 : : sanitize_str(channel_binding_type))));
2849 peter_e@gmx.net 1060 :CBC 4 : break;
3105 heikki.linnakangas@i 1061 :UBC 0 : default:
1062 [ # # ]: 0 : ereport(ERROR,
1063 : : (errcode(ERRCODE_PROTOCOL_VIOLATION),
1064 : : errmsg("malformed SCRAM message"),
1065 : : errdetail("Unexpected channel-binding flag \"%s\".",
1066 : : sanitize_char(*p))));
1067 : : }
1068 : :
1069 : : /*
1070 : : * Forbid optional authzid (authorization identity). We don't support it.
1071 : : */
2396 peter@eisentraut.org 1072 [ - + ]:CBC 58 : if (*p == 'a')
3105 heikki.linnakangas@i 1073 [ # # ]:UBC 0 : ereport(ERROR,
1074 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
1075 : : errmsg("client uses authorization identity, but it is not supported")));
2396 peter@eisentraut.org 1076 [ - + ]:CBC 58 : if (*p != ',')
3105 heikki.linnakangas@i 1077 [ # # ]:UBC 0 : ereport(ERROR,
1078 : : (errcode(ERRCODE_PROTOCOL_VIOLATION),
1079 : : errmsg("malformed SCRAM message"),
1080 : : errdetail("Unexpected attribute \"%s\" in client-first-message.",
1081 : : sanitize_char(*p))));
2396 peter@eisentraut.org 1082 :CBC 58 : p++;
1083 : :
1084 : 58 : state->client_first_message_bare = pstrdup(p);
1085 : :
1086 : : /*
1087 : : * Any mandatory extensions would go here. We don't support any.
1088 : : *
1089 : : * RFC 5802 specifies error code "e=extensions-not-supported" for this,
1090 : : * but it can only be sent in the server-final message. We prefer to fail
1091 : : * immediately (which the RFC also allows).
1092 : : */
1093 [ - + ]: 58 : if (*p == 'm')
3105 heikki.linnakangas@i 1094 [ # # ]:UBC 0 : ereport(ERROR,
1095 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
1096 : : errmsg("client requires an unsupported SCRAM extension")));
1097 : :
1098 : : /*
1099 : : * Read username. Note: this is ignored. We use the username from the
1100 : : * startup message instead, still it is kept around if provided as it
1101 : : * proves to be useful for debugging purposes.
1102 : : */
2396 peter@eisentraut.org 1103 :CBC 58 : state->client_username = read_attr_value(&p, 'n');
1104 : :
1105 : : /* read nonce and check that it is made of only printable characters */
1106 : 58 : state->client_nonce = read_attr_value(&p, 'r');
3105 heikki.linnakangas@i 1107 [ - + ]: 58 : if (!is_scram_printable(state->client_nonce))
3105 heikki.linnakangas@i 1108 [ # # ]:UBC 0 : ereport(ERROR,
1109 : : (errcode(ERRCODE_PROTOCOL_VIOLATION),
1110 : : errmsg("non-printable characters in SCRAM nonce")));
1111 : :
1112 : : /*
1113 : : * There can be any number of optional extensions after this. We don't
1114 : : * support any extensions, so ignore them.
1115 : : */
2396 peter@eisentraut.org 1116 [ - + ]:CBC 58 : while (*p != '\0')
2396 peter@eisentraut.org 1117 :UBC 0 : read_any_attr(&p, NULL);
1118 : :
1119 : : /* success! */
3105 heikki.linnakangas@i 1120 :CBC 58 : }
1121 : :
1122 : : /*
1123 : : * Verify the final nonce contained in the last message received from
1124 : : * client in an exchange.
1125 : : */
1126 : : static bool
1127 : 58 : verify_final_nonce(scram_state *state)
1128 : : {
1129 : 58 : int client_nonce_len = strlen(state->client_nonce);
1130 : 58 : int server_nonce_len = strlen(state->server_nonce);
1131 : 58 : int final_nonce_len = strlen(state->client_final_nonce);
1132 : :
1133 [ - + ]: 58 : if (final_nonce_len != client_nonce_len + server_nonce_len)
3105 heikki.linnakangas@i 1134 :UBC 0 : return false;
3105 heikki.linnakangas@i 1135 [ - + ]:CBC 58 : if (memcmp(state->client_final_nonce, state->client_nonce, client_nonce_len) != 0)
3105 heikki.linnakangas@i 1136 :UBC 0 : return false;
3105 heikki.linnakangas@i 1137 [ - + ]:CBC 58 : if (memcmp(state->client_final_nonce + client_nonce_len, state->server_nonce, server_nonce_len) != 0)
3105 heikki.linnakangas@i 1138 :UBC 0 : return false;
1139 : :
3105 heikki.linnakangas@i 1140 :CBC 58 : return true;
1141 : : }
1142 : :
1143 : : /*
1144 : : * Verify the client proof contained in the last message received from
1145 : : * client in an exchange. Returns true if the verification is a success,
1146 : : * or false for a failure.
1147 : : */
1148 : : static bool
1149 : 58 : verify_client_proof(scram_state *state)
1150 : : {
1151 : : uint8 ClientSignature[SCRAM_MAX_KEY_LEN];
1152 : : uint8 client_StoredKey[SCRAM_MAX_KEY_LEN];
991 michael@paquier.xyz 1153 : 58 : pg_hmac_ctx *ctx = pg_hmac_create(state->hash_type);
1154 : : int i;
1332 1155 : 58 : const char *errstr = NULL;
1156 : :
1157 : : /*
1158 : : * Calculate ClientSignature. Note that we don't log directly a failure
1159 : : * here even when processing the calculations as this could involve a mock
1160 : : * authentication.
1161 : : */
991 1162 [ + - + - ]: 116 : if (pg_hmac_init(ctx, state->StoredKey, state->key_length) < 0 ||
1617 1163 : 58 : pg_hmac_update(ctx,
1164 : 58 : (uint8 *) state->client_first_message_bare,
1165 [ + - ]: 116 : strlen(state->client_first_message_bare)) < 0 ||
1166 [ + - ]: 116 : pg_hmac_update(ctx, (uint8 *) ",", 1) < 0 ||
1167 : 58 : pg_hmac_update(ctx,
1168 : 58 : (uint8 *) state->server_first_message,
1169 [ + - ]: 116 : strlen(state->server_first_message)) < 0 ||
1170 [ + - ]: 116 : pg_hmac_update(ctx, (uint8 *) ",", 1) < 0 ||
1171 : 58 : pg_hmac_update(ctx,
1172 : 58 : (uint8 *) state->client_final_message_without_proof,
1173 [ - + ]: 116 : strlen(state->client_final_message_without_proof)) < 0 ||
991 1174 : 58 : pg_hmac_final(ctx, ClientSignature, state->key_length) < 0)
1175 : : {
1332 michael@paquier.xyz 1176 [ # # ]:UBC 0 : elog(ERROR, "could not calculate client signature: %s",
1177 : : pg_hmac_error(ctx));
1178 : : }
1179 : :
1617 michael@paquier.xyz 1180 :CBC 58 : pg_hmac_free(ctx);
1181 : :
1182 : : /* Extract the ClientKey that the client calculated from the proof */
991 1183 [ + + ]: 1914 : for (i = 0; i < state->key_length; i++)
234 peter@eisentraut.org 1184 : 1856 : state->ClientKey[i] = state->ClientProof[i] ^ ClientSignature[i];
1185 : :
1186 : : /* Hash it one more time, and compare with StoredKey */
1187 [ - + ]: 58 : if (scram_H(state->ClientKey, state->hash_type, state->key_length,
1188 : : client_StoredKey, &errstr) < 0)
1332 michael@paquier.xyz 1189 [ # # ]:UBC 0 : elog(ERROR, "could not hash stored key: %s", errstr);
1190 : :
991 michael@paquier.xyz 1191 [ + + ]:CBC 58 : if (memcmp(client_StoredKey, state->StoredKey, state->key_length) != 0)
3105 heikki.linnakangas@i 1192 : 5 : return false;
1193 : :
1194 : 53 : return true;
1195 : : }
1196 : :
1197 : : /*
1198 : : * Build the first server-side message sent to the client in a SCRAM
1199 : : * communication exchange.
1200 : : */
1201 : : static char *
1202 : 58 : build_server_first_message(scram_state *state)
1203 : : {
1204 : : /*------
1205 : : * The syntax for the server-first-message is: (RFC 5802)
1206 : : *
1207 : : * server-first-message =
1208 : : * [reserved-mext ","] nonce "," salt ","
1209 : : * iteration-count ["," extensions]
1210 : : *
1211 : : * nonce = "r=" c-nonce [s-nonce]
1212 : : * ;; Second part provided by server.
1213 : : *
1214 : : * c-nonce = printable
1215 : : *
1216 : : * s-nonce = printable
1217 : : *
1218 : : * salt = "s=" base64
1219 : : *
1220 : : * iteration-count = "i=" posit-number
1221 : : * ;; A positive number.
1222 : : *
1223 : : * Example:
1224 : : *
1225 : : * r=fyko+d2lbbFgONRv9qkxdawL3rfcNHYJY1ZVvWVs7j,s=QSXCR+Q6sek8bf92,i=4096
1226 : : *------
1227 : : */
1228 : :
1229 : : /*
1230 : : * Per the spec, the nonce may consist of any printable ASCII characters.
1231 : : * For convenience, however, we don't use the whole range available,
1232 : : * rather, we generate some random bytes, and base64 encode them.
1233 : : */
1234 : : uint8 raw_nonce[SCRAM_RAW_NONCE_LEN];
1235 : : int encoded_len;
1236 : :
2440 michael@paquier.xyz 1237 [ - + ]: 58 : if (!pg_strong_random(raw_nonce, SCRAM_RAW_NONCE_LEN))
3012 heikki.linnakangas@i 1238 [ # # ]:UBC 0 : ereport(ERROR,
1239 : : (errcode(ERRCODE_INTERNAL_ERROR),
1240 : : errmsg("could not generate random nonce")));
1241 : :
2256 michael@paquier.xyz 1242 :CBC 58 : encoded_len = pg_b64_enc_len(SCRAM_RAW_NONCE_LEN);
1243 : : /* don't forget the zero-terminator */
1244 : 58 : state->server_nonce = palloc(encoded_len + 1);
1245 : 58 : encoded_len = pg_b64_encode(raw_nonce, SCRAM_RAW_NONCE_LEN,
1246 : : state->server_nonce, encoded_len);
1247 [ - + ]: 58 : if (encoded_len < 0)
2256 michael@paquier.xyz 1248 [ # # ]:UBC 0 : ereport(ERROR,
1249 : : (errcode(ERRCODE_INTERNAL_ERROR),
1250 : : errmsg("could not encode random nonce")));
3105 heikki.linnakangas@i 1251 :CBC 58 : state->server_nonce[encoded_len] = '\0';
1252 : :
1253 : 58 : state->server_first_message =
1459 peter@eisentraut.org 1254 : 58 : psprintf("r=%s%s,s=%s,i=%d",
1255 : : state->client_nonce, state->server_nonce,
1256 : : state->salt, state->iterations);
1257 : :
3068 heikki.linnakangas@i 1258 : 58 : return pstrdup(state->server_first_message);
1259 : : }
1260 : :
1261 : :
1262 : : /*
1263 : : * Read and parse the final message received from client.
1264 : : */
1265 : : static void
2396 peter@eisentraut.org 1266 : 58 : read_client_final_message(scram_state *state, const char *input)
1267 : : {
1268 : : char attr;
1269 : : char *channel_binding;
1270 : : char *value;
1271 : : char *begin,
1272 : : *proof;
1273 : : char *p;
1274 : : uint8 *client_proof;
1275 : : int client_proof_len;
1276 : :
3105 heikki.linnakangas@i 1277 : 58 : begin = p = pstrdup(input);
1278 : :
1279 : : /*------
1280 : : * The syntax for the server-first-message is: (RFC 5802)
1281 : : *
1282 : : * gs2-header = gs2-cbind-flag "," [ authzid ] ","
1283 : : * ;; GS2 header for SCRAM
1284 : : * ;; (the actual GS2 header includes an optional
1285 : : * ;; flag to indicate that the GSS mechanism is not
1286 : : * ;; "standard", but since SCRAM is "standard", we
1287 : : * ;; don't include that flag).
1288 : : *
1289 : : * cbind-input = gs2-header [ cbind-data ]
1290 : : * ;; cbind-data MUST be present for
1291 : : * ;; gs2-cbind-flag of "p" and MUST be absent
1292 : : * ;; for "y" or "n".
1293 : : *
1294 : : * channel-binding = "c=" base64
1295 : : * ;; base64 encoding of cbind-input.
1296 : : *
1297 : : * proof = "p=" base64
1298 : : *
1299 : : * client-final-message-without-proof =
1300 : : * channel-binding "," nonce [","
1301 : : * extensions]
1302 : : *
1303 : : * client-final-message =
1304 : : * client-final-message-without-proof "," proof
1305 : : *------
1306 : : */
1307 : :
1308 : : /*
1309 : : * Read channel binding. This repeats the channel-binding flags and is
1310 : : * then followed by the actual binding data depending on the type.
1311 : : */
1312 : 58 : channel_binding = read_attr_value(&p, 'c');
2589 1313 [ + + ]: 58 : if (state->channel_binding_in_use)
1314 : : {
1315 : : #ifdef USE_SSL
2849 peter_e@gmx.net 1316 : 4 : const char *cbind_data = NULL;
1317 : 4 : size_t cbind_data_len = 0;
1318 : : size_t cbind_header_len;
1319 : : char *cbind_input;
1320 : : size_t cbind_input_len;
1321 : : char *b64_message;
1322 : : int b64_message_len;
1323 : :
2845 1324 [ - + ]: 4 : Assert(state->cbind_flag == 'p');
1325 : :
1326 : : /* Fetch hash data of server's SSL certificate */
2589 heikki.linnakangas@i 1327 : 4 : cbind_data = be_tls_get_certificate_hash(state->port,
1328 : : &cbind_data_len);
1329 : :
1330 : : /* should not happen */
2849 peter_e@gmx.net 1331 [ + - - + ]: 4 : if (cbind_data == NULL || cbind_data_len == 0)
2589 heikki.linnakangas@i 1332 [ # # ]:UBC 0 : elog(ERROR, "could not get server certificate hash");
1333 : :
2589 heikki.linnakangas@i 1334 :CBC 4 : cbind_header_len = strlen("p=tls-server-end-point,,"); /* p=type,, */
2849 peter_e@gmx.net 1335 : 4 : cbind_input_len = cbind_header_len + cbind_data_len;
1336 : 4 : cbind_input = palloc(cbind_input_len);
2589 heikki.linnakangas@i 1337 : 4 : snprintf(cbind_input, cbind_input_len, "p=tls-server-end-point,,");
2849 peter_e@gmx.net 1338 : 4 : memcpy(cbind_input + cbind_header_len, cbind_data, cbind_data_len);
1339 : :
2256 michael@paquier.xyz 1340 : 4 : b64_message_len = pg_b64_enc_len(cbind_input_len);
1341 : : /* don't forget the zero-terminator */
1342 : 4 : b64_message = palloc(b64_message_len + 1);
121 heikki.linnakangas@i 1343 : 4 : b64_message_len = pg_b64_encode((uint8 *) cbind_input, cbind_input_len,
1344 : : b64_message, b64_message_len);
2256 michael@paquier.xyz 1345 [ - + ]: 4 : if (b64_message_len < 0)
2256 michael@paquier.xyz 1346 [ # # ]:UBC 0 : elog(ERROR, "could not encode channel binding data");
2849 peter_e@gmx.net 1347 :CBC 4 : b64_message[b64_message_len] = '\0';
1348 : :
1349 : : /*
1350 : : * Compare the value sent by the client with the value expected by the
1351 : : * server.
1352 : : */
1353 [ - + ]: 4 : if (strcmp(channel_binding, b64_message) != 0)
2849 peter_e@gmx.net 1354 [ # # ]:UBC 0 : ereport(ERROR,
1355 : : (errcode(ERRCODE_INVALID_AUTHORIZATION_SPECIFICATION),
1356 : : errmsg("SCRAM channel binding check failed")));
1357 : : #else
1358 : : /* shouldn't happen, because we checked this earlier already */
1359 : : elog(ERROR, "channel binding not supported by this build");
1360 : : #endif
1361 : : }
1362 : : else
1363 : : {
1364 : : /*
1365 : : * If we are not using channel binding, the binding data is expected
1366 : : * to always be "biws", which is "n,," base64-encoded, or "eSws",
1367 : : * which is "y,,". We also have to check whether the flag is the same
1368 : : * one that the client originally sent.
1369 : : */
2845 peter_e@gmx.net 1370 [ + - - + ]:CBC 54 : if (!(strcmp(channel_binding, "biws") == 0 && state->cbind_flag == 'n') &&
2845 peter_e@gmx.net 1371 [ # # # # ]:UBC 0 : !(strcmp(channel_binding, "eSws") == 0 && state->cbind_flag == 'y'))
2849 1372 [ # # ]: 0 : ereport(ERROR,
1373 : : (errcode(ERRCODE_PROTOCOL_VIOLATION),
1374 : : errmsg("unexpected SCRAM channel-binding attribute in client-final-message")));
1375 : : }
1376 : :
3105 heikki.linnakangas@i 1377 :CBC 58 : state->client_final_nonce = read_attr_value(&p, 'r');
1378 : :
1379 : : /* ignore optional extensions, read until we find "p" attribute */
1380 : : do
1381 : : {
1382 : 58 : proof = p - 1;
1383 : 58 : value = read_any_attr(&p, &attr);
1384 [ - + ]: 58 : } while (attr != 'p');
1385 : :
2256 michael@paquier.xyz 1386 : 58 : client_proof_len = pg_b64_dec_len(strlen(value));
1387 : 58 : client_proof = palloc(client_proof_len);
1388 : 58 : if (pg_b64_decode(value, strlen(value), client_proof,
991 1389 [ - + ]: 58 : client_proof_len) != state->key_length)
3105 heikki.linnakangas@i 1390 [ # # ]:UBC 0 : ereport(ERROR,
1391 : : (errcode(ERRCODE_PROTOCOL_VIOLATION),
1392 : : errmsg("malformed SCRAM message"),
1393 : : errdetail("Malformed proof in client-final-message.")));
991 michael@paquier.xyz 1394 :CBC 58 : memcpy(state->ClientProof, client_proof, state->key_length);
3105 heikki.linnakangas@i 1395 : 58 : pfree(client_proof);
1396 : :
1397 [ - + ]: 58 : if (*p != '\0')
3105 heikki.linnakangas@i 1398 [ # # ]:UBC 0 : ereport(ERROR,
1399 : : (errcode(ERRCODE_PROTOCOL_VIOLATION),
1400 : : errmsg("malformed SCRAM message"),
1401 : : errdetail("Garbage found at the end of client-final-message.")));
1402 : :
3105 heikki.linnakangas@i 1403 :CBC 58 : state->client_final_message_without_proof = palloc(proof - begin + 1);
1404 : 58 : memcpy(state->client_final_message_without_proof, input, proof - begin);
1405 : 58 : state->client_final_message_without_proof[proof - begin] = '\0';
1406 : 58 : }
1407 : :
1408 : : /*
1409 : : * Build the final server-side message of an exchange.
1410 : : */
1411 : : static char *
1412 : 53 : build_server_final_message(scram_state *state)
1413 : : {
1414 : : uint8 ServerSignature[SCRAM_MAX_KEY_LEN];
1415 : : char *server_signature_base64;
1416 : : int siglen;
991 michael@paquier.xyz 1417 : 53 : pg_hmac_ctx *ctx = pg_hmac_create(state->hash_type);
1418 : :
1419 : : /* calculate ServerSignature */
1420 [ + - + - ]: 106 : if (pg_hmac_init(ctx, state->ServerKey, state->key_length) < 0 ||
1617 1421 : 53 : pg_hmac_update(ctx,
1422 : 53 : (uint8 *) state->client_first_message_bare,
1423 [ + - ]: 106 : strlen(state->client_first_message_bare)) < 0 ||
1424 [ + - ]: 106 : pg_hmac_update(ctx, (uint8 *) ",", 1) < 0 ||
1425 : 53 : pg_hmac_update(ctx,
1426 : 53 : (uint8 *) state->server_first_message,
1427 [ + - ]: 106 : strlen(state->server_first_message)) < 0 ||
1428 [ + - ]: 106 : pg_hmac_update(ctx, (uint8 *) ",", 1) < 0 ||
1429 : 53 : pg_hmac_update(ctx,
1430 : 53 : (uint8 *) state->client_final_message_without_proof,
1431 [ - + ]: 106 : strlen(state->client_final_message_without_proof)) < 0 ||
991 1432 : 53 : pg_hmac_final(ctx, ServerSignature, state->key_length) < 0)
1433 : : {
1332 michael@paquier.xyz 1434 [ # # ]:UBC 0 : elog(ERROR, "could not calculate server signature: %s",
1435 : : pg_hmac_error(ctx));
1436 : : }
1437 : :
1617 michael@paquier.xyz 1438 :CBC 53 : pg_hmac_free(ctx);
1439 : :
991 1440 : 53 : siglen = pg_b64_enc_len(state->key_length);
1441 : : /* don't forget the zero-terminator */
2256 1442 : 53 : server_signature_base64 = palloc(siglen + 1);
121 heikki.linnakangas@i 1443 : 53 : siglen = pg_b64_encode(ServerSignature,
1444 : : state->key_length, server_signature_base64,
1445 : : siglen);
2256 michael@paquier.xyz 1446 [ - + ]: 53 : if (siglen < 0)
2256 michael@paquier.xyz 1447 [ # # ]:UBC 0 : elog(ERROR, "could not encode server signature");
3105 heikki.linnakangas@i 1448 :CBC 53 : server_signature_base64[siglen] = '\0';
1449 : :
1450 : : /*------
1451 : : * The syntax for the server-final-message is: (RFC 5802)
1452 : : *
1453 : : * verifier = "v=" base64
1454 : : * ;; base-64 encoded ServerSignature.
1455 : : *
1456 : : * server-final-message = (server-error / verifier)
1457 : : * ["," extensions]
1458 : : *
1459 : : *------
1460 : : */
1461 : 53 : return psprintf("v=%s", server_signature_base64);
1462 : : }
1463 : :
1464 : :
1465 : : /*
1466 : : * Deterministically generate salt for mock authentication, using a SHA256
1467 : : * hash based on the username and a cluster-level secret key. Returns a
1468 : : * pointer to a static buffer of size SCRAM_DEFAULT_SALT_LEN, or NULL.
1469 : : */
1470 : : static uint8 *
991 michael@paquier.xyz 1471 : 1 : scram_mock_salt(const char *username, pg_cryptohash_type hash_type,
1472 : : int key_length)
1473 : : {
1474 : : pg_cryptohash_ctx *ctx;
1475 : : static uint8 sha_digest[SCRAM_MAX_KEY_LEN];
3105 heikki.linnakangas@i 1476 : 1 : char *mock_auth_nonce = GetMockAuthenticationNonce();
1477 : :
1478 : : /*
1479 : : * Generate salt using a SHA256 hash of the username and the cluster's
1480 : : * mock authentication nonce. (This works as long as the salt length is
1481 : : * not larger than the SHA256 digest length. If the salt is smaller, the
1482 : : * caller will just ignore the extra data.)
1483 : : */
1484 : : StaticAssertDecl(PG_SHA256_DIGEST_LENGTH >= SCRAM_DEFAULT_SALT_LEN,
1485 : : "salt length greater than SHA256 digest length");
1486 : :
1487 : : /*
1488 : : * This may be worth refreshing if support for more hash methods is\
1489 : : * added.
1490 : : */
991 michael@paquier.xyz 1491 [ - + ]: 1 : Assert(hash_type == PG_SHA256);
1492 : :
1493 : 1 : ctx = pg_cryptohash_create(hash_type);
1739 1494 [ + - + - ]: 2 : if (pg_cryptohash_init(ctx) < 0 ||
1495 [ + - ]: 2 : pg_cryptohash_update(ctx, (uint8 *) username, strlen(username)) < 0 ||
1496 [ - + ]: 2 : pg_cryptohash_update(ctx, (uint8 *) mock_auth_nonce, MOCK_AUTH_NONCE_LEN) < 0 ||
991 1497 : 1 : pg_cryptohash_final(ctx, sha_digest, key_length) < 0)
1498 : : {
1739 michael@paquier.xyz 1499 :UBC 0 : pg_cryptohash_free(ctx);
1500 : 0 : return NULL;
1501 : : }
1739 michael@paquier.xyz 1502 :CBC 1 : pg_cryptohash_free(ctx);
1503 : :
121 heikki.linnakangas@i 1504 : 1 : return sha_digest;
1505 : : }
|
