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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-15 17:36:47 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-15 17:36:47 +0000
commit0441d265f2bb9da249c7abf333f0f771fadb4ab5 (patch)
tree3f3789daa2f6db22da6e55e92bee0062a7d613fe /src/auth/mech-otp.c
parentInitial commit. (diff)
downloaddovecot-0441d265f2bb9da249c7abf333f0f771fadb4ab5.tar.xz
dovecot-0441d265f2bb9da249c7abf333f0f771fadb4ab5.zip
Adding upstream version 1:2.3.21+dfsg1.upstream/1%2.3.21+dfsg1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/auth/mech-otp.c')
-rw-r--r--src/auth/mech-otp.c240
1 files changed, 240 insertions, 0 deletions
diff --git a/src/auth/mech-otp.c b/src/auth/mech-otp.c
new file mode 100644
index 0000000..58f3db1
--- /dev/null
+++ b/src/auth/mech-otp.c
@@ -0,0 +1,240 @@
+/*
+ * One-Time-Password (RFC 2444) authentication mechanism.
+ *
+ * Copyright (c) 2006 Andrey Panin <pazke@donpac.ru>
+ *
+ * This software is released under the MIT license.
+ */
+
+#include "auth-common.h"
+#include "safe-memset.h"
+#include "hash.h"
+#include "mech.h"
+#include "passdb.h"
+#include "hex-binary.h"
+#include "otp.h"
+#include "mech-otp-common.h"
+
+static void
+otp_send_challenge(struct auth_request *auth_request,
+ const unsigned char *credentials, size_t size)
+{
+ struct otp_auth_request *request =
+ (struct otp_auth_request *)auth_request;
+ const char *answer;
+
+ if (otp_parse_dbentry(t_strndup(credentials, size),
+ &request->state) != 0) {
+ e_error(request->auth_request.mech_event,
+ "invalid OTP data in passdb");
+ auth_request_fail(auth_request);
+ return;
+ }
+
+ if (--request->state.seq < 1) {
+ e_error(request->auth_request.mech_event,
+ "sequence number < 1");
+ auth_request_fail(auth_request);
+ return;
+ }
+
+ request->lock = otp_try_lock(auth_request);
+ if (!request->lock) {
+ e_error(request->auth_request.mech_event,
+ "user is locked, race attack?");
+ auth_request_fail(auth_request);
+ return;
+ }
+
+ answer = p_strdup_printf(request->pool, "otp-%s %u %s ext",
+ digest_name(request->state.algo),
+ request->state.seq, request->state.seed);
+
+ auth_request_handler_reply_continue(auth_request, answer,
+ strlen(answer));
+}
+
+static void
+otp_credentials_callback(enum passdb_result result,
+ const unsigned char *credentials, size_t size,
+ struct auth_request *auth_request)
+{
+ switch (result) {
+ case PASSDB_RESULT_OK:
+ otp_send_challenge(auth_request, credentials, size);
+ break;
+ case PASSDB_RESULT_INTERNAL_FAILURE:
+ auth_request_internal_failure(auth_request);
+ break;
+ default:
+ auth_request_fail(auth_request);
+ break;
+ }
+}
+
+static void
+mech_otp_auth_phase1(struct auth_request *auth_request,
+ const unsigned char *data, size_t data_size)
+{
+ struct otp_auth_request *request =
+ (struct otp_auth_request *)auth_request;
+ const char *authenid, *error;
+ size_t i, count;
+
+ /* authorization ID \0 authentication ID
+ FIXME: we'll ignore authorization ID for now. */
+ authenid = NULL;
+
+ count = 0;
+ for (i = 0; i < data_size; i++) {
+ if (data[i] == '\0') {
+ if (++count == 1)
+ authenid = (const char *) data + i + 1;
+ }
+ }
+
+ if (count != 1) {
+ e_error(request->auth_request.mech_event,
+ "invalid input");
+ auth_request_fail(auth_request);
+ return;
+ }
+
+ if (!auth_request_set_username(auth_request, authenid, &error)) {
+ e_info(auth_request->mech_event, "%s", error);
+ auth_request_fail(auth_request);
+ return;
+ }
+
+ auth_request_lookup_credentials(auth_request, "OTP",
+ otp_credentials_callback);
+}
+
+static void mech_otp_verify(struct auth_request *auth_request,
+ const char *data, bool hex)
+{
+ struct otp_auth_request *request =
+ (struct otp_auth_request *)auth_request;
+ struct otp_state *state = &request->state;
+ unsigned char hash[OTP_HASH_SIZE], cur_hash[OTP_HASH_SIZE];
+ int ret;
+
+ ret = otp_parse_response(data, hash, hex);
+ if (ret < 0) {
+ e_error(request->auth_request.mech_event,
+ "invalid response");
+ auth_request_fail(auth_request);
+ otp_unlock(auth_request);
+ return;
+ }
+
+ otp_next_hash(state->algo, hash, cur_hash);
+
+ ret = memcmp(cur_hash, state->hash, OTP_HASH_SIZE);
+ if (ret != 0) {
+ auth_request_fail(auth_request);
+ otp_unlock(auth_request);
+ return;
+ }
+
+ memcpy(state->hash, hash, sizeof(state->hash));
+
+ auth_request_set_credentials(auth_request, "OTP",
+ otp_print_dbentry(state),
+ otp_set_credentials_callback);
+}
+
+static void mech_otp_verify_init(struct auth_request *auth_request,
+ const char *data, bool hex)
+{
+ struct otp_auth_request *request =
+ (struct otp_auth_request *)auth_request;
+ struct otp_state new_state;
+ unsigned char hash[OTP_HASH_SIZE], cur_hash[OTP_HASH_SIZE];
+ const char *error;
+ int ret;
+
+ ret = otp_parse_init_response(data, &new_state, cur_hash, hex, &error);
+ if (ret < 0) {
+ e_error(request->auth_request.mech_event,
+ "invalid init response, %s", error);
+ auth_request_fail(auth_request);
+ otp_unlock(auth_request);
+ return;
+ }
+
+ otp_next_hash(request->state.algo, cur_hash, hash);
+
+ ret = memcmp(hash, request->state.hash, OTP_HASH_SIZE);
+ if (ret != 0) {
+ auth_request_fail(auth_request);
+ otp_unlock(auth_request);
+ return;
+ }
+
+ auth_request_set_credentials(auth_request, "OTP",
+ otp_print_dbentry(&new_state),
+ otp_set_credentials_callback);
+}
+
+static void
+mech_otp_auth_phase2(struct auth_request *auth_request,
+ const unsigned char *data, size_t data_size)
+{
+ const char *str = t_strndup(data, data_size);
+
+ if (str_begins(str, "hex:")) {
+ mech_otp_verify(auth_request, str + 4, TRUE);
+ } else if (str_begins(str, "word:")) {
+ mech_otp_verify(auth_request, str + 5, FALSE);
+ } else if (str_begins(str, "init-hex:")) {
+ mech_otp_verify_init(auth_request, str + 9, TRUE);
+ } else if (str_begins(str, "init-word:")) {
+ mech_otp_verify_init(auth_request, str + 10, FALSE);
+ } else {
+ e_error(auth_request->mech_event,
+ "unsupported response type");
+ auth_request_fail(auth_request);
+ otp_unlock(auth_request);
+ }
+}
+
+static void
+mech_otp_auth_continue(struct auth_request *auth_request,
+ const unsigned char *data, size_t data_size)
+{
+ if (auth_request->fields.user == NULL) {
+ mech_otp_auth_phase1(auth_request, data, data_size);
+ } else {
+ mech_otp_auth_phase2(auth_request, data, data_size);
+ }
+}
+
+static struct auth_request *mech_otp_auth_new(void)
+{
+ struct otp_auth_request *request;
+ pool_t pool;
+
+ otp_lock_init();
+
+ pool = pool_alloconly_create(MEMPOOL_GROWING"otp_auth_request", 2048);
+ request = p_new(pool, struct otp_auth_request, 1);
+ request->pool = pool;
+ request->lock = FALSE;
+
+ request->auth_request.refcount = 1;
+ request->auth_request.pool = pool;
+ return &request->auth_request;
+}
+
+const struct mech_module mech_otp = {
+ "OTP",
+
+ .flags = MECH_SEC_DICTIONARY | MECH_SEC_ACTIVE | MECH_SEC_ALLOW_NULS,
+ .passdb_need = MECH_PASSDB_NEED_SET_CREDENTIALS,
+
+ mech_otp_auth_new,
+ mech_generic_auth_initial,
+ mech_otp_auth_continue,
+ mech_otp_auth_free
+};