diff options
Diffstat (limited to 'src/pop3/main.c')
| -rw-r--r-- | src/pop3/main.c | 433 |
1 files changed, 433 insertions, 0 deletions
diff --git a/src/pop3/main.c b/src/pop3/main.c new file mode 100644 index 0000000..c929cdb --- /dev/null +++ b/src/pop3/main.c @@ -0,0 +1,433 @@ +/* Copyright (c) 2002-2018 Dovecot authors, see the included COPYING file */ + +#include "pop3-common.h" +#include "ioloop.h" +#include "buffer.h" +#include "istream.h" +#include "istream-concat.h" +#include "ostream.h" +#include "path-util.h" +#include "base64.h" +#include "str.h" +#include "process-title.h" +#include "restrict-access.h" +#include "settings-parser.h" +#include "master-service.h" +#include "master-login.h" +#include "master-interface.h" +#include "var-expand.h" +#include "mail-error.h" +#include "mail-user.h" +#include "mail-namespace.h" +#include "mail-storage-service.h" + +#include <stdio.h> +#include <unistd.h> + +#define IS_STANDALONE() \ + (getenv(MASTER_IS_PARENT_ENV) == NULL) + +static bool verbose_proctitle = FALSE; +static struct mail_storage_service_ctx *storage_service; +static struct master_login *master_login = NULL; + +pop3_client_created_func_t *hook_client_created = NULL; + +pop3_client_created_func_t * +pop3_client_created_hook_set(pop3_client_created_func_t *new_hook) +{ + pop3_client_created_func_t *old_hook = hook_client_created; + + hook_client_created = new_hook; + return old_hook; +} + +void pop3_refresh_proctitle(void) +{ + struct client *client; + string_t *title = t_str_new(128); + + if (!verbose_proctitle) + return; + + str_append_c(title, '['); + switch (pop3_client_count) { + case 0: + str_append(title, "idling"); + break; + case 1: + client = pop3_clients; + str_append(title, client->user->username); + if (client->user->conn.remote_ip != NULL) { + str_append_c(title, ' '); + str_append(title, + net_ip2addr(client->user->conn.remote_ip)); + } + if (client->destroyed) + str_append(title, " (deinit)"); + break; + default: + str_printfa(title, "%u connections", pop3_client_count); + break; + } + str_append_c(title, ']'); + process_title_set(str_c(title)); +} + +static void pop3_die(void) +{ + /* do nothing. pop3 connections typically die pretty quick anyway. */ +} + +static void client_add_input(struct client *client, const buffer_t *buf) +{ + struct ostream *output; + + if (buf != NULL && buf->used > 0) { + struct istream *inputs[] = { + i_stream_create_copy_from_data(buf->data, buf->used), + client->input, + NULL + }; + client->input = i_stream_create_concat(inputs); + i_stream_copy_fd(client->input, inputs[1]); + i_stream_unref(&inputs[0]); + i_stream_unref(&inputs[1]); + i_stream_set_input_pending(client->input, TRUE); + } + + output = client->output; + o_stream_ref(output); + o_stream_cork(output); + (void)client_handle_input(client); + o_stream_uncork(output); + o_stream_unref(&output); +} + +static int +client_create_from_input(const struct mail_storage_service_input *input, + int fd_in, int fd_out, struct client **client_r, + const char **error_r) +{ + const char *lookup_error_str = + "-ERR [SYS/TEMP] "MAIL_ERRSTR_CRITICAL_MSG"\r\n"; + struct mail_storage_service_user *user; + struct mail_user *mail_user; + struct pop3_settings *set; + const char *errstr; + + if (mail_storage_service_lookup_next(storage_service, input, + &user, &mail_user, error_r) <= 0) { + if (write(fd_out, lookup_error_str, strlen(lookup_error_str)) < 0) { + /* ignored */ + } + return -1; + } + restrict_access_allow_coredumps(TRUE); + + set = mail_storage_service_user_get_set(user)[1]; + if (set->verbose_proctitle) + verbose_proctitle = TRUE; + + if (settings_var_expand(&pop3_setting_parser_info, set, + mail_user->pool, mail_user_var_expand_table(mail_user), + &errstr) <= 0) { + *error_r = t_strdup_printf("Failed to expand settings: %s", errstr); + mail_user_deinit(&mail_user); + mail_storage_service_user_unref(&user); + return -1; + } + + *client_r = client_create(fd_in, fd_out, mail_user, user, set); + return 0; +} + +static int lock_session(struct client *client) +{ + int ret; + + i_assert(client->user->namespaces != NULL); + i_assert(client->set->pop3_lock_session); + + if ((ret = pop3_lock_session(client)) <= 0) { + client_send_line(client, ret < 0 ? + "-ERR [SYS/TEMP] Failed to create POP3 session lock." : + "-ERR [IN-USE] Mailbox is locked by another POP3 session."); + client_destroy(client, "Couldn't lock POP3 session"); + return -1; + } + + return 0; +} + +#define MSG_BYE_INTERNAL_ERROR "-ERR "MAIL_ERRSTR_CRITICAL_MSG +static int init_namespaces(struct client *client, bool already_logged_in) +{ + const char *error; + + /* finish initializing the user (see comment in main()) */ + if (mail_namespaces_init(client->user, &error) < 0) { + if (!already_logged_in) + client_send_line(client, MSG_BYE_INTERNAL_ERROR); + + i_error("%s", error); + client_destroy(client, error); + return -1; + } + + i_assert(client->inbox_ns == NULL); + client->inbox_ns = mail_namespace_find_inbox(client->user->namespaces); + i_assert(client->inbox_ns != NULL); + + return 0; +} + +static void client_init_session(struct client *client) +{ + const char *error; + + /* + * RFC 1939 requires that the session lock gets acquired before the + * positive response is sent to the client indicating a transition + * to the TRANSACTION state. + * + * Since the session lock is stored under the INBOX's storage + * directory, the locking code requires that the namespaces are + * initialized first. + * + * If the system administrator configured dovecot to not use session + * locks, we can send back the positive response before the + * potentially long-running namespace initialization occurs. This + * avoids the client possibly timing out during authentication due + * to storage initialization taking too long. + */ + if (client->set->pop3_lock_session) { + if (init_namespaces(client, FALSE) < 0) + return; /* no need to propagate an error */ + + if (lock_session(client) < 0) + return; /* no need to propagate an error */ + + if (!IS_STANDALONE()) + client_send_line(client, "+OK Logged in."); + } else { + if (!IS_STANDALONE()) + client_send_line(client, "+OK Logged in."); + + if (init_namespaces(client, TRUE) < 0) + return; /* no need to propagate an error */ + } + + struct event_reason *reason = event_reason_begin("pop3:initialize"); + int ret = client_init_mailbox(client, &error); + event_reason_end(&reason); + + if (ret < 0) { + i_error("%s", error); + client_destroy(client, error); + } +} + +static void main_stdio_run(const char *username) +{ + struct client *client; + struct mail_storage_service_input input; + buffer_t *input_buf; + const char *value, *error, *input_base64; + + i_zero(&input); + input.module = input.service = "pop3"; + input.username = username != NULL ? username : getenv("USER"); + if (input.username == NULL && IS_STANDALONE()) + input.username = getlogin(); + if (input.username == NULL) + i_fatal("USER environment missing"); + if ((value = getenv("IP")) != NULL) + (void)net_addr2ip(value, &input.remote_ip); + if ((value = getenv("LOCAL_IP")) != NULL) + (void)net_addr2ip(value, &input.local_ip); + + input_base64 = getenv("CLIENT_INPUT"); + input_buf = input_base64 == NULL ? NULL : + t_base64_decode_str(input_base64); + + if (client_create_from_input(&input, STDIN_FILENO, STDOUT_FILENO, + &client, &error) < 0) + i_fatal("%s", error); + client_add_input(client, input_buf); + client_create_finish(client); + + client_init_session(client); + /* client may be destroyed now */ +} + +static void +login_client_connected(const struct master_login_client *login_client, + const char *username, const char *const *extra_fields) +{ + struct client *client; + struct mail_storage_service_input input; + enum mail_auth_request_flags flags = login_client->auth_req.flags; + const char *error; + buffer_t input_buf; + + i_zero(&input); + input.module = input.service = "pop3"; + input.local_ip = login_client->auth_req.local_ip; + input.remote_ip = login_client->auth_req.remote_ip; + input.local_port = login_client->auth_req.local_port; + input.remote_port = login_client->auth_req.remote_port; + input.username = username; + input.userdb_fields = extra_fields; + input.session_id = login_client->session_id; + if ((flags & MAIL_AUTH_REQUEST_FLAG_CONN_SECURED) != 0) + input.conn_secured = TRUE; + if ((flags & MAIL_AUTH_REQUEST_FLAG_CONN_SSL_SECURED) != 0) + input.conn_ssl_secured = TRUE; + + buffer_create_from_const_data(&input_buf, login_client->data, + login_client->auth_req.data_size); + if (client_create_from_input(&input, login_client->fd, login_client->fd, + &client, &error) < 0) { + int fd = login_client->fd; + + i_error("%s", error); + i_close_fd(&fd); + master_service_client_connection_destroyed(master_service); + return; + } + client_add_input(client, &input_buf); + client_create_finish(client); + + client_init_session(client); + /* client may be destroyed now */ +} + +static void login_client_failed(const struct master_login_client *client, + const char *errormsg) +{ + const char *msg; + + msg = t_strdup_printf("-ERR [SYS/TEMP] %s\r\n", errormsg); + if (write(client->fd, msg, strlen(msg)) < 0) { + /* ignored */ + } +} + +static void client_connected(struct master_service_connection *conn) +{ + /* when running standalone, we shouldn't even get here */ + i_assert(master_login != NULL); + + master_service_client_connection_accept(conn); + master_login_add(master_login, conn->fd); +} + +int main(int argc, char *argv[]) +{ + static const struct setting_parser_info *set_roots[] = { + &pop3_setting_parser_info, + NULL + }; + struct master_login_settings login_set; + enum master_service_flags service_flags = 0; + enum mail_storage_service_flags storage_service_flags = + MAIL_STORAGE_SERVICE_FLAG_NO_SSL_CA; + const char *username = NULL, *auth_socket_path = "auth-master"; + int c; + + i_zero(&login_set); + login_set.postlogin_timeout_secs = MASTER_POSTLOGIN_TIMEOUT_DEFAULT; + + if (IS_STANDALONE() && getuid() == 0 && + net_getpeername(1, NULL, NULL) == 0) { + printf("-ERR [SYS/PERM] pop3 binary must not be started from " + "inetd, use pop3-login instead.\n"); + return 1; + } + + if (IS_STANDALONE()) { + service_flags |= MASTER_SERVICE_FLAG_STANDALONE | + MASTER_SERVICE_FLAG_STD_CLIENT; + } else { + service_flags |= MASTER_SERVICE_FLAG_KEEP_CONFIG_OPEN; + } + + /* + * We include MAIL_STORAGE_SERVICE_FLAG_NO_NAMESPACES so that the + * mail_user initialization is fast and we can quickly send back the + * OK response to LOGIN/AUTHENTICATE. Otherwise we risk a very slow + * namespace initialization to cause client timeouts on login. + */ + storage_service_flags |= MAIL_STORAGE_SERVICE_FLAG_NO_NAMESPACES; + + master_service = master_service_init("pop3", service_flags, + &argc, &argv, "a:t:u:"); + while ((c = master_getopt(master_service)) > 0) { + switch (c) { + case 'a': + auth_socket_path = optarg; + break; + case 't': + if (str_to_uint(optarg, &login_set.postlogin_timeout_secs) < 0 || + login_set.postlogin_timeout_secs == 0) + i_fatal("Invalid -t parameter: %s", optarg); + break; + case 'u': + storage_service_flags |= + MAIL_STORAGE_SERVICE_FLAG_USERDB_LOOKUP; + username = optarg; + break; + default: + return FATAL_DEFAULT; + } + } + + const char *error; + if (t_abspath(auth_socket_path, &login_set.auth_socket_path, &error) < 0) { + i_fatal("t_abspath(%s) failed: %s", auth_socket_path, error); + } + if (argv[optind] != NULL) { + if (t_abspath(argv[optind], &login_set.postlogin_socket_path, &error) < 0) { + i_fatal("t_abspath(%s) failed: %s", argv[optind], error); + } + } + login_set.callback = login_client_connected; + login_set.failure_callback = login_client_failed; + login_set.update_proctitle = + getenv(MASTER_VERBOSE_PROCTITLE_ENV) != NULL && + master_service_get_client_limit(master_service) == 1; + if (!IS_STANDALONE()) + master_login = master_login_init(master_service, &login_set); + + master_service_set_die_callback(master_service, pop3_die); + + storage_service = + mail_storage_service_init(master_service, + set_roots, storage_service_flags); + master_service_init_finish(master_service); + /* NOTE: login_set.*_socket_path are now invalid due to data stack + having been freed */ + + /* fake that we're running, so we know if client was destroyed + while handling its initial input */ + io_loop_set_running(current_ioloop); + + if (IS_STANDALONE()) { + T_BEGIN { + main_stdio_run(username); + } T_END; + } else { + io_loop_set_running(current_ioloop); + } + + if (io_loop_is_running(current_ioloop)) + master_service_run(master_service, client_connected); + clients_destroy_all(); + + if (master_login != NULL) + master_login_deinit(&master_login); + mail_storage_service_deinit(&storage_service); + master_service_deinit(&master_service); + return 0; +} |