/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */ /* Cherokee * * Authors: * Alvaro Lopez Ortega * Daniel Silverstone * * Copyright (C) 2001-2014 Alvaro Lopez Ortega * * This program is free software; you can redistribute it and/or * modify it under the terms of version 2 of the GNU General Public * License as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA * 02110-1301, USA. */ #include "common-internal.h" #include "handler_cgi.h" #include "util.h" #ifdef HAVE_STDARG_H # include #endif #include #include #include #include #include #include #include #include #include #include #ifdef HAVE_SYS_WAIT_H # include #endif #include "module.h" #include "connection.h" #include "connection-protected.h" #include "socket.h" #include "server.h" #include "server-protected.h" #include "header.h" #include "header-protected.h" #include "post.h" #include "error_log.h" #include "services.h" #define ENTRIES "handler,cgi" # define fork_and_execute_cgi(c) fork_and_execute_cgi_unix(c) static ret_t fork_and_execute_cgi_unix (cherokee_handler_cgi_t *cgi); #define set_env(cgi,k,v,vl) cherokee_handler_cgi_add_env_pair(cgi, k, sizeof(k)-1, v, vl) static ret_t fork_and_execute_cgi_via_spawner(cherokee_handler_cgi_t *cgi); /* Plugin initialization */ CGI_LIB_INIT (cgi, http_get | http_post | http_head); static ret_t read_from_cgi (cherokee_handler_cgi_base_t *cgi_base, cherokee_buffer_t *buffer) { ret_t ret; size_t read_ = 0; cherokee_handler_cgi_t *cgi = HDL_CGI(cgi_base); /* Sanity check: pipe() accessed */ if (unlikely (cgi->pipeInput < 0)) return ret_eof; /* Read the data from the pipe: */ ret = cherokee_buffer_read_from_fd (buffer, cgi->pipeInput, 4096, &read_); TRACE (ENTRIES, "read... ret=%d %d\n", ret, read_); switch (ret) { case ret_eagain: cherokee_thread_deactive_to_polling (HANDLER_THREAD(cgi), HANDLER_CONN(cgi), cgi->pipeInput, FDPOLL_MODE_READ, false); return ret_eagain; case ret_ok: TRACE (ENTRIES, "%d bytes read\n", read_); return ret_ok; case ret_eof: case ret_error: cgi_base->got_eof = true; return ret; default: RET_UNKNOWN(ret); } SHOULDNT_HAPPEN; return ret_error; } ret_t cherokee_handler_cgi_new (cherokee_handler_t **hdl, void *cnt, cherokee_module_props_t *props) { int i; CHEROKEE_NEW_STRUCT (n, handler_cgi); /* Init the base class */ cherokee_handler_cgi_base_init (HDL_CGI_BASE(n), cnt, PLUGIN_INFO_HANDLER_PTR(cgi), HANDLER_PROPS(props), cherokee_handler_cgi_add_env_pair, read_from_cgi); /* Virtual methods */ MODULE(n)->init = (module_func_init_t) cherokee_handler_cgi_init; MODULE(n)->free = (module_func_free_t) cherokee_handler_cgi_free; HANDLER(n)->read_post = (handler_func_read_post_t) cherokee_handler_cgi_read_post; /* Virtual methods: implemented by handler_cgi_base */ HANDLER(n)->add_headers = (handler_func_add_headers_t) cherokee_handler_cgi_base_add_headers; HANDLER(n)->step = (handler_func_step_t) cherokee_handler_cgi_base_step; /* Init */ n->pipeInput = -1; n->pipeOutput = -1; n->pid = -1; n->envp_last = 0; for (i=0; ienvp[i] = NULL; /* Return the object */ *hdl = HANDLER(n); return ret_ok; } static int do_reap (void) { pid_t pid; int status; int child_count = 0; /* Reap defunct children until there aren't any more. */ for (child_count = 0; ; ++child_count) { pid = waitpid (-1, &status, WNOHANG); /* none left */ if (pid == 0) break; else if (pid < 0) { /* because of ptrace */ if (errno == EINTR) continue; break; } } return child_count; } ret_t cherokee_handler_cgi_free (cherokee_handler_cgi_t *cgi) { int i; /* Free the rest of the handler CGI memory */ cherokee_handler_cgi_base_free (HDL_CGI_BASE(cgi)); /* Close the connection with the CGI */ if (cgi->pipeInput > 0) { cherokee_fd_close (cgi->pipeInput); cgi->pipeInput = -1; } if (cgi->pipeOutput > 0) { cherokee_fd_close (cgi->pipeOutput); cgi->pipeOutput = -1; } /* Kill the CGI */ if (cgi->pid > 0) { pid_t pid; cint_t tries = 2; while (true) { do { pid = waitpid (cgi->pid, NULL, WNOHANG); } while ((pid == 1) && (errno == EINTR)); if (pid > 0) { /* Ok */ break; } else if (errno == ECHILD) { /* Already death */ break; } /* Failed */ kill (cgi->pid, SIGTERM); tries--; if (tries < 0) break; } } /* Free the environment variables */ for (i=0; ienvp_last; i++) { free (cgi->envp[i]); cgi->envp[i] = NULL; } /* For some reason, we have seen that the SIGCHLD signal does not call to * our handler in a server with a lot of requests, so the wait() call, * necessary to free the resources used by the CGI, is not called. So I * think that a possible solution couble be to put the waitpid call in the * _free method of this handler, so when the handler ends, this will free * the resources used by our cool CGI. */ do_reap(); return ret_ok; } ret_t cherokee_handler_cgi_props_free (cherokee_handler_cgi_props_t *props) { return cherokee_handler_cgi_base_props_free (PROP_CGI_BASE(props)); } ret_t cherokee_handler_cgi_configure (cherokee_config_node_t *conf, cherokee_server_t *srv, cherokee_module_props_t **_props) { /* Instance a new property object */ if (*_props == NULL) { CHEROKEE_NEW_STRUCT (n, handler_cgi_props); cherokee_handler_cgi_base_props_init_base (PROP_CGI_BASE(n), MODULE_PROPS_FREE(cherokee_handler_cgi_props_free)); *_props = MODULE_PROPS(n); } /* Parse local options */ return cherokee_handler_cgi_base_configure (conf, srv, _props); } void cherokee_handler_cgi_add_env_pair (cherokee_handler_cgi_base_t *cgi_base, const char *name, int name_len, const char *content, int content_len) { cherokee_handler_cgi_t *cgi = HDL_CGI(cgi_base); char *entry; /* Build the new envp entry */ if (name == NULL) return; entry = (char *) malloc (name_len + content_len + 2); if (entry == NULL) return; memcpy (entry, name, name_len); entry[name_len] = '='; memcpy (entry + name_len + 1, content, content_len); entry[name_len+content_len+1] = '\0'; /* Set it in the table */ cgi->envp[cgi->envp_last] = entry; cgi->envp_last++; /* Sanity check */ if (cgi->envp_last >= ENV_VAR_NUM) { SHOULDNT_HAPPEN; } } static ret_t add_environment (cherokee_handler_cgi_t *cgi, cherokee_connection_t *conn) { ret_t ret; cherokee_handler_cgi_base_t *cgi_base = HDL_CGI_BASE(cgi); cherokee_buffer_t *tmp = THREAD_TMP_BUF2(CONN_THREAD(conn)); ret = cherokee_handler_cgi_base_build_envp (HDL_CGI_BASE(cgi), conn); if (unlikely (ret != ret_ok)) return ret; /* CONTENT_LENGTH */ if (conn->post.has_info) { cherokee_buffer_clean (tmp); cherokee_buffer_add_ullong10 (tmp, conn->post.len); set_env (cgi_base, "CONTENT_LENGTH", tmp->buf, tmp->len); } /* SCRIPT_FILENAME */ if (cgi_base->executable.len <= 0) return ret_error; set_env (cgi_base, "SCRIPT_FILENAME", cgi_base->executable.buf, cgi_base->executable.len); return ret_ok; } ret_t cherokee_handler_cgi_init (cherokee_handler_cgi_t *cgi) { ret_t ret; cherokee_handler_cgi_base_t *cgi_base = HDL_CGI_BASE(cgi); cherokee_connection_t *conn = HANDLER_CONN(cgi); switch (cgi_base->init_phase) { case hcgi_phase_build_headers: /* Extracts PATH_INFO and filename from request uri */ if (cherokee_buffer_is_empty (&cgi_base->executable)) { ret = cherokee_handler_cgi_base_extract_path (cgi_base, true); if (unlikely (ret < ret_ok)) { return ret; } } /* It has to update the timeout of the connection, * otherwhise the server will drop it for the CGI * isn't fast enough */ conn->timeout = cherokee_bogonow_now + CGI_TIMEOUT; cgi_base->init_phase = hcgi_phase_connect; case hcgi_phase_connect: /* Launch the CGI */ ret = fork_and_execute_cgi_via_spawner(cgi); if (unlikely (ret != ret_ok)) { ret = fork_and_execute_cgi(cgi); if (unlikely (ret != ret_ok)) { return ret; } } default: break; } TRACE (ENTRIES, "finishing %s\n", "ret_ok"); return ret_ok; } ret_t cherokee_handler_cgi_read_post (cherokee_handler_cgi_t *cgi) { ret_t ret; cherokee_connection_t *conn = HANDLER_CONN(cgi); cherokee_socket_status_t blocking = socket_closed; cherokee_boolean_t did_IO = false; if (! conn->post.has_info) { return ret_ok; } ret = cherokee_post_send_to_fd (&conn->post, &conn->socket, cgi->pipeOutput, NULL, &blocking, &did_IO); if (did_IO) { cherokee_connection_update_timeout (conn); } switch (ret) { case ret_ok: break; case ret_eagain: if (blocking == socket_writing) { cherokee_thread_deactive_to_polling (HANDLER_THREAD(cgi), conn, cgi->pipeOutput, FDPOLL_MODE_WRITE, false); return ret_deny; } /* ret_eagain - Block on read * ret_deny - Block on back-end write */ if (cherokee_post_has_buffered_info (&conn->post)) { return ret_deny; } return ret_eagain; default: return ret; } TRACE (ENTRIES",post", "%s\n", "finished"); cherokee_fd_close (cgi->pipeOutput); cgi->pipeOutput = -1; return ret_ok; } static ret_t _fd_set_properties (int fd, int add_flags, int remove_flags) { int flags; flags = fcntl (fd, F_GETFL, 0); flags |= add_flags; flags &= ~remove_flags; if (fcntl (fd, F_SETFL, flags) == -1) { LOG_ERRNO (errno, cherokee_err_error, CHEROKEE_ERROR_HANDLER_CGI_SET_PROP, fd); return ret_error; } return ret_ok; } static NORETURN void manage_child_cgi_process (cherokee_handler_cgi_t *cgi, int pipe_cgi[2], int pipe_server[2]) { /* Child process */ int re; cherokee_connection_t *conn = HANDLER_CONN(cgi); cherokee_handler_cgi_base_t *cgi_base = HDL_CGI_BASE(cgi); char *absolute_path = cgi_base->executable.buf; char *argv[2] = { NULL, NULL }; #ifdef TRACE_ENABLED TRACE(ENTRIES, "About to execute: '%s'\n", absolute_path); if (! cherokee_buffer_is_empty (&conn->effective_directory)) TRACE(ENTRIES, "Effective directory: '%s'\n", conn->effective_directory.buf); else TRACE(ENTRIES, "No Effective directory %s", "\n"); #endif /* Close useless sides */ cherokee_fd_close (pipe_cgi[0]); cherokee_fd_close (pipe_server[1]); /* Change stdin and out */ cherokee_fd_close (STDIN_FILENO); re = dup2 (pipe_server[0], STDIN_FILENO); cherokee_fd_close (pipe_server[0]); if (unlikely (re != 0)) { printf ("Status: 500" CRLF_CRLF); printf ("X-Debug: file=%s line=%d" CRLF_CRLF, __FILE__, __LINE__); exit(1); } cherokee_fd_close (STDOUT_FILENO); re |= dup2 (pipe_cgi[1], STDOUT_FILENO); cherokee_fd_close (pipe_cgi[1]); /* Redirect the stderr */ if ((CONN_VSRV(conn)->error_writer != NULL) && (CONN_VSRV(conn)->error_writer->fd != -1)) { cherokee_fd_close (STDERR_FILENO); dup2 (CONN_VSRV(conn)->error_writer->fd, STDERR_FILENO); } # if 0 /* Set unbuffered */ setvbuf (stdin, NULL, _IONBF, 0); setvbuf (stdout, NULL, _IONBF, 0); # endif /* Enable blocking mode */ _fd_set_properties (STDIN_FILENO, 0, O_NONBLOCK); _fd_set_properties (STDOUT_FILENO, 0, O_NONBLOCK); _fd_set_properties (STDERR_FILENO, 0, O_NONBLOCK); /* Sets the new environ. */ add_environment (cgi, conn); /* Change the directory */ if (! cherokee_buffer_is_empty (&conn->effective_directory)) { re = chdir (conn->effective_directory.buf); } else { char *file = strrchr (absolute_path, '/'); if (file != NULL) { *file = '\0'; re = chdir (absolute_path); *file = '/'; } else { re = -1; } } if (re < 0) { printf ("Status: 500" CRLF_CRLF); printf ("X-Debug: file=%s line=%d" CRLF_CRLF, __FILE__, __LINE__); exit(1); } /* Build de argv array */ argv[0] = absolute_path; /* Change the execution user? */ if (HANDLER_CGI_PROPS(cgi_base)->change_user) { struct stat nocache_info; struct stat *info; cherokee_iocache_entry_t *io_entry = NULL; cherokee_server_t *srv = CONN_SRV(conn); cherokee_handler_cgi_base_props_t *props = HANDLER_CGI_BASE_PROPS(cgi); ret_t ret = cherokee_io_stat (srv->iocache, &cgi_base->executable, props->use_cache, &nocache_info, &io_entry, &info); if (ret != ret_ok) { info = &nocache_info; } re = setuid (info->st_uid); if (re != 0) { LOG_ERROR (CHEROKEE_ERROR_HANDLER_CGI_SETID, absolute_path, info->st_uid); } cherokee_iocache_entry_unref(&io_entry); } /* Reset the server-wide signal handlers */ cherokee_reset_signals(); /* Lets go.. execute it! */ do { re = execve (absolute_path, argv, cgi->envp); } while ((re == -1) && (errno == EINTR)); if (re < 0) { int err = errno; char buferr[ERROR_MAX_BUFSIZE]; switch (err) { case ENODEV: case ENOTDIR: case ENOENT: printf ("Status: 404" CRLF_CRLF); exit(0); case EPERM: case EACCES: case ENOEXEC: printf ("Status: 403" CRLF_CRLF); exit(0); default: printf ("Status: 500" CRLF_CRLF); printf ("X-Debug: file=%s line=%d cmd=%s errno=%d: %s" CRLF_CRLF, __FILE__, __LINE__, absolute_path, err, strerror(err)); } /* Don't use the logging system (concurrency issues) */ LOG_ERROR (CHEROKEE_ERROR_HANDLER_CGI_EXECUTE, absolute_path, cherokee_strerror_r(err, buferr, sizeof(buferr))); exit(1); } /* There is no way, it could reach this point. */ SHOULDNT_HAPPEN; exit(2); } static ret_t fork_and_execute_cgi_unix (cherokee_handler_cgi_t *cgi) { int re; int pid; cherokee_connection_t *conn = HANDLER_CONN(cgi); struct { int cgi[2]; int server[2]; } pipes; /* Creates the pipes ... */ re = cherokee_pipe (pipes.cgi); re |= cherokee_pipe (pipes.server); if (re != 0) { conn->error_code = http_internal_error; return ret_error; } /* .. and fork the process */ pid = fork(); if (pid == 0) { /* CGI process */ manage_child_cgi_process (cgi, pipes.cgi, pipes.server); } else if (pid < 0) { /* Error */ cherokee_fd_close (pipes.cgi[0]); cherokee_fd_close (pipes.cgi[1]); cherokee_fd_close (pipes.server[0]); cherokee_fd_close (pipes.server[1]); conn->error_code = http_internal_error; return ret_error; } TRACE (ENTRIES, "pid %d\n", pid); cherokee_fd_close (pipes.server[0]); cherokee_fd_close (pipes.cgi[1]); cgi->pid = pid; cgi->pipeInput = pipes.cgi[0]; cgi->pipeOutput = pipes.server[1]; /* Set to Input to NON-BLOCKING */ _fd_set_properties (cgi->pipeInput, O_NDELAY|O_NONBLOCK, 0); return ret_ok; } static ret_t fork_and_execute_cgi_via_spawner(cherokee_handler_cgi_t *cgi) { int re; int pid = -1; cherokee_connection_t *conn = HANDLER_CONN(cgi); cherokee_handler_cgi_base_t *cgi_base = HDL_CGI_BASE(cgi); ret_t ret; uid_t uid; gid_t gid; cherokee_buffer_t empty = CHEROKEE_BUF_INIT; cherokee_buffer_t username = CHEROKEE_BUF_INIT; cherokee_services_fdmap_t fd_map; cherokee_buffer_t *chdir = NULL; cherokee_buffer_t chdir_backing = CHEROKEE_BUF_INIT; struct passwd ent; char ent_tmp[1024]; struct { int cgi[2]; int server[2]; } pipes; TRACE (ENTRIES, "Trying to create CGI via spawner\n"); if (! cherokee_buffer_is_empty (&conn->effective_directory)) { chdir = &conn->effective_directory; } else { int ofs = cgi_base->executable.len - 1; while (ofs >= 0 && cgi_base->executable.buf[ofs] != '/') { ofs--; } TRACE (ENTRIES, "While building chdir, ofs=%d\n", ofs); if (ofs < 0 || cherokee_buffer_add (&chdir_backing, cgi_base->executable.buf, ofs + 1) != ret_ok) { conn->error_code = http_internal_error; TRACE (ENTRIES, "Failed, cannot build chdir entry\n"); cherokee_buffer_mrproper(&chdir_backing); return ret_error; } chdir = &chdir_backing; } /* Creates the pipes ... */ re = cherokee_pipe (pipes.cgi); re |= cherokee_pipe (pipes.server); if (re != 0) { conn->error_code = http_internal_error; cherokee_buffer_mrproper(&chdir_backing); TRACE (ENTRIES, "Failed, cannot build pipes\n"); return ret_error; } if (HANDLER_CGI_PROPS(cgi_base)->change_user) { struct stat nocache_info; struct stat *info; cherokee_iocache_entry_t *io_entry = NULL; cherokee_server_t *srv = CONN_SRV(conn); cherokee_handler_cgi_base_props_t *props = HANDLER_CGI_BASE_PROPS(cgi); ret = cherokee_io_stat (srv->iocache, &cgi_base->executable, props->use_cache, &nocache_info, &io_entry, &info); if (ret != ret_ok) { info = &nocache_info; nocache_info.st_uid = getuid(); nocache_info.st_gid = getgid(); } uid = info->st_uid; gid = info->st_gid; cherokee_iocache_entry_unref(&io_entry); } else { /* Not changing, so launch as the same uid/gid as the worker */ uid = getuid(); gid = getgid(); } /* Determine the username of the owner of the file */ ret = cherokee_getpwuid(uid, &ent, ent_tmp, sizeof (ent_tmp)); if (ret != ret_ok || cherokee_buffer_add(&username, ent.pw_name, strlen(ent.pw_name) != ret_ok)) { cherokee_fd_close(pipes.cgi[0]); cherokee_fd_close(pipes.cgi[1]); cherokee_fd_close(pipes.server[0]); cherokee_fd_close(pipes.server[1]); conn->error_code = http_internal_error; cherokee_buffer_mrproper(&chdir_backing); cherokee_buffer_mrproper(&username); TRACE (ENTRIES, "Failed, Unable to retrieve username for uid %d\n", uid); return ret_error; } /* Update the environment ready to run */ add_environment (cgi, conn); /* Set up the FD map */ fd_map.fd_in = pipes.server[0]; fd_map.fd_out = pipes.cgi[1]; if ((CONN_VSRV(conn)->error_writer != NULL) && (CONN_VSRV(conn)->error_writer->fd != -1)) { fd_map.fd_err = CONN_VSRV(conn)->error_writer->fd; } else { fd_map.fd_err = fd_map.fd_out; } TRACE (ENTRIES, "Doing Spawn\n"); ret = cherokee_services_client_spawn (&cgi_base->executable, &username, uid, gid, &empty, chdir, false, cgi->envp, CONN_VSRV(conn)->error_writer, &pid, &fd_map); cherokee_buffer_mrproper(&chdir_backing); cherokee_buffer_mrproper(&username); /* Close the client FDs */ cherokee_fd_close (pipes.server[0]); cherokee_fd_close (pipes.cgi[1]); /* Did we fail to try to spawn? */ if (ret != ret_ok) { /* Close the server FDs too */ cherokee_fd_close (pipes.server[1]); cherokee_fd_close (pipes.cgi[0]); TRACE (ENTRIES, "Failed to spawn\n"); return ret; } /* Did we try, but fail, to spawn? */ if (pid == -1) { /* Close the server FDs too */ cherokee_fd_close (pipes.server[1]); cherokee_fd_close (pipes.cgi[0]); TRACE (ENTRIES, "Spawned, but failed server side\n"); return ret_error; } /* Successfully launched */ cgi->pid = pid; cgi->pipeInput = pipes.cgi[0]; cgi->pipeOutput = pipes.server[1]; /* Set to Input to NON-BLOCKING */ _fd_set_properties (cgi->pipeInput, O_NDELAY|O_NONBLOCK, 0); TRACE (ENTRIES, "CGI running, PID=%d\n", pid); return ret_ok; }