1 files changed, 88 insertions, 0 deletions
diff --git a/src/auth/mech-plain.c b/src/auth/mech-plain.c
new file mode 100644
index 0000000..3bb715f
--- /dev/null
+++ b/src/auth/mech-plain.c
@@ -0,0 +1,88 @@
+/* Copyright (c) 2002-2018 Dovecot authors, see the included COPYING file */
+
+#include "auth-common.h"
+#include "safe-memset.h"
+#include "mech.h"
+#include "passdb.h"
+#include "mech-plain-common.h"
+
+static void
+mech_plain_auth_continue(struct auth_request *request,
+			 const unsigned char *data, size_t data_size)
+{
+	const char *authid, *authenid, *error;
+	char *pass;
+	size_t i, len;
+	int count;
+
+	/* authorization ID \0 authentication ID \0 pass. */
+	authid = (const char *) data;
+	authenid = NULL; pass = NULL;
+
+	count = 0;
+	for (i = 0; i < data_size; i++) {
+		if (data[i] == '\0') {
+			if (++count == 1)
+				authenid = (const char *) data + i+1;
+			else if (count == 2) {
+				i++;
+				len = data_size - i;
+				pass = p_strndup(unsafe_data_stack_pool,
+						 data+i, len);
+			}
+			else
+				break;
+		}
+	}
+
+	if (count == 2 && authenid != NULL && strcmp(authid, authenid) == 0) {
+		/* the login username isn't different */
+		authid = "";
+	}
+
+	if (count != 2) {
+		/* invalid input */
+		e_info(request->mech_event, "invalid input");
+		auth_request_fail(request);
+	} else if (!auth_request_set_username(request, authenid, &error)) {
+                /* invalid username */
+                e_info(request->mech_event, "%s", error);
+                auth_request_fail(request);
+        } else if (*authid != '\0' &&
+                   !auth_request_set_login_username(request, authid, &error)) {
+                /* invalid login username */
+                e_info(request->mech_event,
+		       "login user: %s", error);
+                auth_request_fail(request);
+        } else {
+                auth_request_verify_plain(request, pass,
+                                          plain_verify_callback);
+	}
+
+        /* make sure it's cleared */
+	if (pass != NULL)
+		safe_memset(pass, 0, strlen(pass));
+}
+
+static struct auth_request *mech_plain_auth_new(void)
+{
+        struct auth_request *request;
+	pool_t pool;
+
+	pool = pool_alloconly_create(MEMPOOL_GROWING"plain_auth_request", 2048);
+	request = p_new(pool, struct auth_request, 1);
+	request->pool = pool;
+	return request;
+}
+
+const struct mech_module mech_plain = {
+	"PLAIN",
+
+	.flags = MECH_SEC_PLAINTEXT | MECH_SEC_ALLOW_NULS,
+	.passdb_need = MECH_PASSDB_NEED_VERIFY_PLAIN,
+
+	mech_plain_auth_new,
+	mech_generic_auth_initial,
+	mech_plain_auth_continue,
+	mech_generic_auth_free
+};