/* * demo-json-rpc-server.c: JSON-RPC 2.0 demo server * * Copyright (c) 2015, Přemysl Janouch * All rights reserved. * * Permission to use, copy, modify, and/or distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. * */ #define print_fatal_data ((void *) LOG_ERR) #define print_error_data ((void *) LOG_ERR) #define print_warning_data ((void *) LOG_WARNING) #define print_status_data ((void *) LOG_INFO) #define print_debug_data ((void *) LOG_DEBUG) #define LIBERTY_WANT_SSL #include "config.h" #include "liberty/liberty.c" #include #include #include #include #include #include #include // FIXME: don't include the implementation, include the header and compile // the implementation separately #include "http-parser/http_parser.c" // --- Extensions to liberty --------------------------------------------------- // These should be incorporated into the library ASAP #define UNPACKER_INT_BEGIN \ if (self->len - self->offset < sizeof *value) \ return false; \ uint8_t *x = (uint8_t *) self->data + self->offset; \ self->offset += sizeof *value; static bool msg_unpacker_u16 (struct msg_unpacker *self, uint16_t *value) { UNPACKER_INT_BEGIN *value = (uint16_t) x[0] << 24 | (uint16_t) x[1] << 16; return true; } static bool msg_unpacker_u32 (struct msg_unpacker *self, uint32_t *value) { UNPACKER_INT_BEGIN *value = (uint32_t) x[0] << 24 | (uint32_t) x[1] << 16 | (uint32_t) x[2] << 8 | (uint32_t) x[3]; return true; } #undef UNPACKER_INT_BEGIN // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - // "msg_writer" should be rewritten on top of this static void str_pack_u8 (struct str *self, uint8_t x) { str_append_data (self, &x, 1); } static void str_pack_u16 (struct str *self, uint64_t x) { uint8_t tmp[2] = { x >> 8, x }; str_append_data (self, tmp, sizeof tmp); } static void str_pack_u32 (struct str *self, uint32_t x) { uint32_t u = x; uint8_t tmp[4] = { u >> 24, u >> 16, u >> 8, u }; str_append_data (self, tmp, sizeof tmp); } static void str_pack_i32 (struct str *self, int32_t x) { str_pack_u32 (self, (uint32_t) x); } static void str_pack_u64 (struct str *self, uint64_t x) { uint8_t tmp[8] = { x >> 56, x >> 48, x >> 40, x >> 32, x >> 24, x >> 16, x >> 8, x }; str_append_data (self, tmp, sizeof tmp); } // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - static int tolower_ascii (int c) { return c >= 'A' && c <= 'Z' ? c + ('a' - 'A') : c; } static size_t tolower_ascii_strxfrm (char *dest, const char *src, size_t n) { size_t len = strlen (src); while (n-- && (*dest++ = tolower_ascii (*src++))) ; return len; } static void base64_encode (const void *data, size_t len, struct str *output) { const char *alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; const uint8_t *p = data; size_t n_groups = len / 3; size_t tail = len - n_groups * 3; uint32_t group; for (; n_groups--; p += 3) { group = p[0] << 16 | p[1] << 8 | p[2]; str_append_c (output, alphabet[(group >> 18) & 63]); str_append_c (output, alphabet[(group >> 12) & 63]); str_append_c (output, alphabet[(group >> 6) & 63]); str_append_c (output, alphabet[ group & 63]); } switch (tail) { case 2: group = p[0] << 16 | p[1] << 8; str_append_c (output, alphabet[(group >> 18) & 63]); str_append_c (output, alphabet[(group >> 12) & 63]); str_append_c (output, alphabet[(group >> 6) & 63]); str_append_c (output, '='); break; case 1: group = p[0] << 16; str_append_c (output, alphabet[(group >> 18) & 63]); str_append_c (output, alphabet[(group >> 12) & 63]); str_append_c (output, '='); str_append_c (output, '='); default: break; } } // --- libev helpers ----------------------------------------------------------- static bool flush_queue (write_queue_t *queue, ev_io *watcher) { struct iovec vec[queue->len], *vec_iter = vec; for (write_req_t *iter = queue->head; iter; iter = iter->next) *vec_iter++ = iter->data; ssize_t written; again: written = writev (watcher->fd, vec, N_ELEMENTS (vec)); if (written < 0) { if (errno == EAGAIN) goto skip; if (errno == EINTR) goto again; return false; } write_queue_processed (queue, written); skip: if (write_queue_is_empty (queue)) ev_io_stop (EV_DEFAULT_ watcher); else ev_io_start (EV_DEFAULT_ watcher); return true; } // --- Logging ----------------------------------------------------------------- static void log_message_syslog (void *user_data, const char *quote, const char *fmt, va_list ap) { int prio = (int) (intptr_t) user_data; va_list va; va_copy (va, ap); int size = vsnprintf (NULL, 0, fmt, va); va_end (va); if (size < 0) return; char buf[size + 1]; if (vsnprintf (buf, sizeof buf, fmt, ap) >= 0) syslog (prio, "%s%s", quote, buf); } // --- FastCGI ----------------------------------------------------------------- // Constants from the FastCGI specification document #define FCGI_HEADER_LEN 8 #define FCGI_VERSION_1 1 #define FCGI_NULL_REQUEST_ID 0 #define FCGI_KEEP_CONN 1 enum fcgi_type { FCGI_BEGIN_REQUEST = 1, FCGI_ABORT_REQUEST = 2, FCGI_END_REQUEST = 3, FCGI_PARAMS = 4, FCGI_STDIN = 5, FCGI_STDOUT = 6, FCGI_STDERR = 7, FCGI_DATA = 8, FCGI_GET_VALUES = 9, FCGI_GET_VALUES_RESULT = 10, FCGI_UNKNOWN_TYPE = 11, FCGI_MAXTYPE = FCGI_UNKNOWN_TYPE }; enum fcgi_role { FCGI_RESPONDER = 1, FCGI_AUTHORIZER = 2, FCGI_FILTER = 3 }; enum fcgi_protocol_status { FCGI_REQUEST_COMPLETE = 0, FCGI_CANT_MPX_CONN = 1, FCGI_OVERLOADED = 2, FCGI_UNKNOWN_ROLE = 3 }; #define FCGI_MAX_CONNS "FCGI_MAX_CONNS" #define FCGI_MAX_REQS "FCGI_MAX_REQS" #define FCGI_MPXS_CONNS "FCGI_MPXS_CONNS" // - - Message stream parser - - - - - - - - - - - - - - - - - - - - - - - - - - struct fcgi_parser; typedef void (*fcgi_message_fn) (const struct fcgi_parser *parser, void *user_data); enum fcgi_parser_state { FCGI_READING_HEADER, ///< Reading the fixed header portion FCGI_READING_CONTENT, ///< Reading the message content FCGI_READING_PADDING ///< Reading the padding }; struct fcgi_parser { enum fcgi_parser_state state; ///< Parsing state struct str input; ///< Input buffer // The next block of fields is considered public: uint8_t version; ///< FastCGI protocol version uint8_t type; ///< FastCGI record type uint16_t request_id; ///< FastCGI request ID struct str content; ///< Message data uint16_t content_length; ///< Message content length uint8_t padding_length; ///< Message padding length fcgi_message_fn on_message; ///< Callback on message void *user_data; ///< User data }; static void fcgi_parser_init (struct fcgi_parser *self) { memset (self, 0, sizeof *self); str_init (&self->input); str_init (&self->content); } static void fcgi_parser_free (struct fcgi_parser *self) { str_free (&self->input); str_free (&self->content); } static void fcgi_parser_unpack_header (struct fcgi_parser *self) { struct msg_unpacker unpacker; msg_unpacker_init (&unpacker, self->input.str, self->input.len); bool success = true; uint8_t reserved; success &= msg_unpacker_u8 (&unpacker, &self->version); success &= msg_unpacker_u8 (&unpacker, &self->type); success &= msg_unpacker_u16 (&unpacker, &self->request_id); success &= msg_unpacker_u16 (&unpacker, &self->content_length); success &= msg_unpacker_u8 (&unpacker, &self->padding_length); success &= msg_unpacker_u8 (&unpacker, &reserved); hard_assert (success); str_remove_slice (&self->input, 0, unpacker.offset); } static void fcgi_parser_push (struct fcgi_parser *self, const void *data, size_t len) { // This could be made considerably faster for high-throughput applications // if we use a circular buffer instead of constantly calling memmove() str_append_data (&self->input, data, len); while (true) switch (self->state) { case FCGI_READING_HEADER: if (self->input.len < FCGI_HEADER_LEN) return; fcgi_parser_unpack_header (self); self->state = FCGI_READING_CONTENT; break; case FCGI_READING_CONTENT: if (self->input.len < self->content_length) return; // Move an appropriate part of the input buffer to the content buffer str_reset (&self->content); str_append_data (&self->content, self->input.str, self->content_length); str_remove_slice (&self->input, 0, self->content_length); self->state = FCGI_READING_PADDING; break; case FCGI_READING_PADDING: if (self->input.len < self->padding_length) return; // Call the callback to further process the message self->on_message (self, self->user_data); // Remove the padding from the input buffer str_remove_slice (&self->input, 0, self->padding_length); self->state = FCGI_READING_HEADER; break; } } // - - Name-value pair parser - - - - - - - - - - - - - - - - - - - - - - - - - enum fcgi_nv_parser_state { FCGI_NV_PARSER_NAME_LEN, ///< The first name length octet FCGI_NV_PARSER_NAME_LEN_FULL, ///< Remaining name length octets FCGI_NV_PARSER_VALUE_LEN, ///< The first value length octet FCGI_NV_PARSER_VALUE_LEN_FULL, ///< Remaining value length octets FCGI_NV_PARSER_NAME, ///< Reading the name FCGI_NV_PARSER_VALUE ///< Reading the value }; struct fcgi_nv_parser { struct str_map *output; ///< Where the pairs will be stored enum fcgi_nv_parser_state state; ///< Parsing state struct str input; ///< Input buffer uint32_t name_len; ///< Length of the name uint32_t value_len; ///< Length of the value char *name; ///< The current name, 0-terminated char *value; ///< The current value, 0-terminated }; static void fcgi_nv_parser_init (struct fcgi_nv_parser *self) { memset (self, 0, sizeof *self); str_init (&self->input); } static void fcgi_nv_parser_free (struct fcgi_nv_parser *self) { str_free (&self->input); free (self->name); free (self->value); } static void fcgi_nv_parser_push (struct fcgi_nv_parser *self, const void *data, size_t len) { // This could be optimized significantly; I'm not even trying str_append_data (&self->input, data, len); while (true) { struct msg_unpacker unpacker; msg_unpacker_init (&unpacker, self->input.str, self->input.len); switch (self->state) { uint8_t len; uint32_t len_full; case FCGI_NV_PARSER_NAME_LEN: if (!msg_unpacker_u8 (&unpacker, &len)) return; if (len >> 7) self->state = FCGI_NV_PARSER_NAME_LEN_FULL; else { self->name_len = len; str_remove_slice (&self->input, 0, unpacker.offset); self->state = FCGI_NV_PARSER_VALUE_LEN; } break; case FCGI_NV_PARSER_NAME_LEN_FULL: if (!msg_unpacker_u32 (&unpacker, &len_full)) return; self->name_len = len_full & ~(1U << 31); str_remove_slice (&self->input, 0, unpacker.offset); self->state = FCGI_NV_PARSER_VALUE_LEN; break; case FCGI_NV_PARSER_VALUE_LEN: if (!msg_unpacker_u8 (&unpacker, &len)) return; if (len >> 7) self->state = FCGI_NV_PARSER_VALUE_LEN_FULL; else { self->value_len = len; str_remove_slice (&self->input, 0, unpacker.offset); self->state = FCGI_NV_PARSER_NAME; } break; case FCGI_NV_PARSER_VALUE_LEN_FULL: if (!msg_unpacker_u32 (&unpacker, &len_full)) return; self->value_len = len_full & ~(1U << 31); str_remove_slice (&self->input, 0, unpacker.offset); self->state = FCGI_NV_PARSER_NAME; break; case FCGI_NV_PARSER_NAME: if (self->input.len < self->name_len) return; self->name = xmalloc (self->name_len + 1); self->name[self->name_len] = '\0'; memcpy (self->name, self->input.str, self->name_len); str_remove_slice (&self->input, 0, self->name_len); self->state = FCGI_NV_PARSER_VALUE; break; case FCGI_NV_PARSER_VALUE: if (self->input.len < self->value_len) return; self->value = xmalloc (self->value_len + 1); self->value[self->value_len] = '\0'; memcpy (self->value, self->input.str, self->value_len); str_remove_slice (&self->input, 0, self->value_len); self->state = FCGI_NV_PARSER_NAME_LEN; // The map takes ownership of the value str_map_set (self->output, self->name, self->value); free (self->name); self->name = NULL; self->value = NULL; break; } } } // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - static void fcgi_nv_convert_len (size_t len, struct str *output) { if (len < 0x80) str_pack_u8 (output, len); else { len |= (uint32_t) 1 << 31; str_pack_u32 (output, len); } } static void fcgi_nv_convert (struct str_map *map, struct str *output) { struct str_map_iter iter; str_map_iter_init (&iter, map); while (str_map_iter_next (&iter)) { const char *name = iter.link->key; const char *value = iter.link->data; size_t name_len = iter.link->key_length; size_t value_len = strlen (value); fcgi_nv_convert_len (name_len, output); fcgi_nv_convert_len (value_len, output); str_append_data (output, name, name_len); str_append_data (output, value, value_len); } } // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - enum fcgi_request_state { FCGI_REQUEST_PARAMS, ///< Reading headers FCGI_REQUEST_STDIN ///< Reading input }; struct fcgi_request { struct fcgi_muxer *muxer; ///< The parent muxer uint16_t request_id; ///< The ID of this request uint8_t flags; ///< Request flags enum fcgi_request_state state; ///< Parsing state struct str_map headers; ///< Headers struct fcgi_nv_parser hdr_parser; ///< Header parser struct str output_buffer; ///< Output buffer void *handler_data; ///< Handler data }; struct fcgi_muxer { struct fcgi_parser parser; ///< FastCGI message parser // TODO: bool quitting; that causes us to reject all requests? /// Requests assigned to request IDs // TODO: allocate this dynamically struct fcgi_request *requests[1 << 16]; void (*write_cb) (void *user_data, const void *data, size_t len); void (*close_cb) (void *user_data); void *(*request_start_cb) (void *user_data, struct fcgi_request *request); void (*request_push_cb) (void *handler_data, const void *data, size_t len); void (*request_destroy_cb) (void *handler_data); void *user_data; ///< User data for callbacks }; static void fcgi_muxer_send (struct fcgi_muxer *self, enum fcgi_type type, uint16_t request_id, const void *data, size_t len) { hard_assert (len <= UINT16_MAX); struct str message; str_init (&message); str_pack_u8 (&message, FCGI_VERSION_1); str_pack_u8 (&message, type); str_pack_u16 (&message, request_id); str_pack_u16 (&message, len); // content length str_pack_u8 (&message, 0); // padding length str_append_data (&message, data, len); // XXX: we should probably have another write_cb that assumes ownership self->write_cb (self->user_data, message.str, message.len); str_free (&message); } static void fcgi_muxer_send_end_request (struct fcgi_muxer *self, uint16_t request_id, uint32_t app_status, enum fcgi_protocol_status protocol_status) { uint8_t content[8] = { app_status >> 24, app_status >> 16, app_status << 8, app_status, protocol_status }; fcgi_muxer_send (self, FCGI_END_REQUEST, request_id, content, sizeof content); } // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - static void fcgi_request_init (struct fcgi_request *self) { memset (self, 0, sizeof *self); str_map_init (&self->headers); self->headers.free = free; fcgi_nv_parser_init (&self->hdr_parser); self->hdr_parser.output = &self->headers; } static void fcgi_request_free (struct fcgi_request *self) { str_map_free (&self->headers); fcgi_nv_parser_free (&self->hdr_parser); } static void fcgi_request_push_params (struct fcgi_request *self, const void *data, size_t len) { if (self->state != FCGI_REQUEST_PARAMS) { // TODO: probably reject the request return; } if (len) fcgi_nv_parser_push (&self->hdr_parser, data, len); else { // TODO: probably check the state of the header parser // TODO: request_start() can return false, end the request here? self->handler_data = self->muxer->request_start_cb (self->muxer->user_data, self); self->state = FCGI_REQUEST_STDIN; } } static void fcgi_request_push_stdin (struct fcgi_request *self, const void *data, size_t len) { if (self->state != FCGI_REQUEST_STDIN) { // TODO: probably reject the request return; } self->muxer->request_push_cb (self->handler_data, data, len); } static void fcgi_request_flush (struct fcgi_request *self) { if (!self->output_buffer.len) return; fcgi_muxer_send (self->muxer, FCGI_STDOUT, self->request_id, self->output_buffer.str, self->output_buffer.len); str_reset (&self->output_buffer); } static void fcgi_request_write (struct fcgi_request *self, const void *data, size_t len) { // We're buffering the output and splitting it into messages bool need_flush = true; while (len) { size_t to_write = UINT16_MAX - self->output_buffer.len; if (to_write > len) { to_write = len; need_flush = false; } str_append_data (&self->output_buffer, data, to_write); data = (uint8_t *) data + to_write; len -= to_write; if (need_flush) fcgi_request_flush (self); } } static void fcgi_request_finish (struct fcgi_request *self) { // TODO: flush(), end_request(), delete self, muxer->request_destroy_cb()? } // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - typedef void (*fcgi_muxer_handler_fn) (struct fcgi_muxer *, const struct fcgi_parser *); static void fcgi_muxer_on_get_values (struct fcgi_muxer *self, const struct fcgi_parser *parser) { struct str_map values; str_map_init (&values); values.free = free; struct str_map response; str_map_init (&response); response.free = free; struct fcgi_nv_parser nv_parser; fcgi_nv_parser_init (&nv_parser); nv_parser.output = &values; fcgi_nv_parser_push (&nv_parser, parser->content.str, parser->content.len); struct str_map_iter iter; str_map_iter_init (&iter, &values); while (str_map_iter_next (&iter)) { const char *key = iter.link->key; // TODO: if (!strcmp (key, FCGI_MAX_CONNS)) // TODO: if (!strcmp (key, FCGI_MAX_REQS)) if (!strcmp (key, FCGI_MPXS_CONNS)) str_map_set (&response, key, xstrdup ("1")); } struct str content; str_init (&content); fcgi_nv_convert (&response, &content); fcgi_muxer_send (self, FCGI_GET_VALUES_RESULT, parser->request_id, content.str, content.len); str_free (&content); str_map_free (&values); str_map_free (&response); } static void fcgi_muxer_on_begin_request (struct fcgi_muxer *self, const struct fcgi_parser *parser) { struct msg_unpacker unpacker; msg_unpacker_init (&unpacker, parser->content.str, parser->content.len); uint16_t role; uint8_t flags; bool success = true; success &= msg_unpacker_u16 (&unpacker, &role); success &= msg_unpacker_u8 (&unpacker, &flags); // Ignoring 5 reserved bytes if (!success) { print_debug ("FastCGI: ignoring invalid %s message", STRINGIFY (FCGI_BEGIN_REQUEST)); return; } // We can only act as a responder, reject everything else up front if (role != FCGI_RESPONDER) { fcgi_muxer_send_end_request (self, parser->request_id, 0, FCGI_UNKNOWN_ROLE); return; } struct fcgi_request *request = self->requests[parser->request_id]; if (request) { // TODO: fail return; } request = xcalloc (1, sizeof *request); fcgi_request_init (request); request->muxer = self; request->request_id = parser->request_id; request->flags = flags; self->requests[parser->request_id] = request; } static void fcgi_muxer_on_abort_request (struct fcgi_muxer *self, const struct fcgi_parser *parser) { struct fcgi_request *request = self->requests[parser->request_id]; if (!request) { print_debug ("FastCGI: received %s for an unknown request", STRINGIFY (FCGI_ABORT_REQUEST)); return; } // TODO: abort the request: let it somehow produce FCGI_END_REQUEST } static void fcgi_muxer_on_params (struct fcgi_muxer *self, const struct fcgi_parser *parser) { struct fcgi_request *request = self->requests[parser->request_id]; if (!request) { print_debug ("FastCGI: received %s for an unknown request", STRINGIFY (FCGI_PARAMS)); return; } fcgi_request_push_params (request, parser->content.str, parser->content.len); } static void fcgi_muxer_on_stdin (struct fcgi_muxer *self, const struct fcgi_parser *parser) { struct fcgi_request *request = self->requests[parser->request_id]; if (!request) { print_debug ("FastCGI: received %s for an unknown request", STRINGIFY (FCGI_STDIN)); return; } fcgi_request_push_stdin (request, parser->content.str, parser->content.len); } static void fcgi_muxer_on_message (const struct fcgi_parser *parser, void *user_data) { struct fcgi_muxer *self = user_data; if (parser->version != FCGI_VERSION_1) { print_debug ("FastCGI: unsupported version %d", parser->version); // TODO: also return false to stop processing on protocol error? return; } static const fcgi_muxer_handler_fn handlers[] = { [FCGI_GET_VALUES] = fcgi_muxer_on_get_values, [FCGI_BEGIN_REQUEST] = fcgi_muxer_on_begin_request, [FCGI_ABORT_REQUEST] = fcgi_muxer_on_abort_request, [FCGI_PARAMS] = fcgi_muxer_on_params, [FCGI_STDIN] = fcgi_muxer_on_stdin, }; fcgi_muxer_handler_fn handler; if (parser->type >= N_ELEMENTS (handlers) || !(handler = handlers[parser->type])) { uint8_t content[8] = { parser->type }; fcgi_muxer_send (self, FCGI_UNKNOWN_TYPE, parser->request_id, content, sizeof content); return; } handler (self, parser); } static void fcgi_muxer_init (struct fcgi_muxer *self) { fcgi_parser_init (&self->parser); self->parser.on_message = fcgi_muxer_on_message; self->parser.user_data = self; } static void fcgi_muxer_free (struct fcgi_muxer *self) { fcgi_parser_free (&self->parser); } static void fcgi_muxer_push (struct fcgi_muxer *self, const void *data, size_t len) { fcgi_parser_push (&self->parser, data, len); } // --- SCGI -------------------------------------------------------------------- enum scgi_parser_state { SCGI_READING_NETSTRING_LENGTH, ///< The length of the header netstring SCGI_READING_NAME, ///< Header name SCGI_READING_VALUE, ///< Header value SCGI_READING_CONTENT ///< Incoming data }; struct scgi_parser { enum scgi_parser_state state; ///< Parsing state struct str input; ///< Input buffer struct str_map headers; ///< Headers parsed size_t headers_len; ///< Length of the netstring contents struct str name; ///< Header name so far struct str value; ///< Header value so far /// Finished parsing request headers. /// Return false to abort further processing of input. bool (*on_headers_read) (void *user_data); /// Content available; len == 0 means end of file. /// Return false to abort further processing of input. bool (*on_content) (void *user_data, const void *data, size_t len); void *user_data; ///< User data passed to callbacks }; static void scgi_parser_init (struct scgi_parser *self) { str_init (&self->input); str_map_init (&self->headers); self->headers.free = free; str_init (&self->name); str_init (&self->value); } static void scgi_parser_free (struct scgi_parser *self) { str_free (&self->input); str_map_free (&self->headers); str_free (&self->name); str_free (&self->value); } static bool scgi_parser_push (struct scgi_parser *self, const void *data, size_t len, struct error **e) { if (!len) { if (self->state != SCGI_READING_CONTENT) { error_set (e, "premature EOF"); return false; } // Indicate end of file return self->on_content (self->user_data, NULL, 0); } // Notice that this madness is significantly harder to parse than FastCGI; // this procedure could also be optimized significantly str_append_data (&self->input, data, len); bool keep_running = true; while (keep_running) switch (self->state) { case SCGI_READING_NETSTRING_LENGTH: { if (self->input.len < 1) return true; char digit = *self->input.str; // XXX: this allows for omitting the netstring length altogether if (digit == ':') { self->state = SCGI_READING_NAME; break; } if (digit < '0' || digit >= '9') { error_set (e, "invalid header netstring"); return false; } size_t new_len = self->headers_len * 10 + (digit - '0'); if (new_len < self->headers_len) { error_set (e, "header netstring is too long"); return false; } self->headers_len = new_len; str_remove_slice (&self->input, 0, 1); break; } case SCGI_READING_NAME: { if (self->input.len < 1) return true; char c = *self->input.str; if (!self->headers_len) { // The netstring is ending but we haven't finished parsing it, // or the netstring doesn't end with a comma if (self->name.len || c != ',') { error_set (e, "invalid header netstring"); return false; } self->state = SCGI_READING_CONTENT; keep_running = self->on_headers_read (self->user_data); } else if (c != '\0') str_append_c (&self->name, c); else self->state = SCGI_READING_VALUE; str_remove_slice (&self->input, 0, 1); break; } case SCGI_READING_VALUE: { if (self->input.len < 1) return true; char c = *self->input.str; if (!self->headers_len) { // The netstring is ending but we haven't finished parsing it error_set (e, "invalid header netstring"); return false; } else if (c != '\0') str_append_c (&self->value, c); else { // We've got a name-value pair, let's put it in the map str_map_set (&self->headers, self->name.str, str_steal (&self->value)); str_reset (&self->name); str_init (&self->value); self->state = SCGI_READING_NAME; } str_remove_slice (&self->input, 0, 1); break; } case SCGI_READING_CONTENT: keep_running = self->on_content (self->user_data, self->input.str, self->input.len); str_remove_slice (&self->input, 0, self->input.len); return keep_running; } return false; } // --- WebSockets -------------------------------------------------------------- #define WS_GUID "258EAFA5-E914-47DA-95CA-C5AB0DC85B11" #define SEC_WS_KEY "Sec-WebSocket-Key" #define SEC_WS_ACCEPT "Sec-WebSocket-Accept" #define SEC_WS_PROTOCOL "Sec-WebSocket-Protocol" #define SEC_WS_VERSION "Sec-WebSocket-Version" #define WS_MAX_CONTROL_PAYLOAD_LEN 125 static char * ws_encode_response_key (const char *key) { char *response_key = xstrdup_printf ("%s" WS_GUID, key); unsigned char hash[SHA_DIGEST_LENGTH]; SHA1 ((unsigned char *) response_key, strlen (response_key), hash); free (response_key); struct str base64; str_init (&base64); base64_encode (hash, sizeof hash, &base64); return str_steal (&base64); } enum ws_status { // These names aren't really standard, just somewhat descriptive. // The RFC isn't really much cleaner about their meaning. WS_STATUS_NORMAL = 1000, WS_STATUS_GOING_AWAY = 1001, WS_STATUS_PROTOCOL = 1002, WS_STATUS_UNACCEPTABLE = 1003, WS_STATUS_INCONSISTENT = 1007, WS_STATUS_POLICY = 1008, WS_STATUS_TOO_BIG = 1009, WS_STATUS_EXTENSION = 1010, WS_STATUS_UNEXPECTED = 1011, // Reserved for internal usage WS_STATUS_MISSING = 1005, WS_STATUS_ABNORMAL = 1006, WS_STATUS_TLS = 1015 }; // - - Frame parser - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - enum ws_parser_state { WS_PARSER_FIXED, ///< Parsing fixed length part WS_PARSER_PAYLOAD_LEN_16, ///< Parsing extended payload length WS_PARSER_PAYLOAD_LEN_64, ///< Parsing extended payload length WS_PARSER_MASK, ///< Parsing masking-key WS_PARSER_PAYLOAD ///< Parsing payload }; enum ws_opcode { // Non-control WS_OPCODE_CONT = 0, WS_OPCODE_TEXT = 1, WS_OPCODE_BINARY = 2, // Control WS_OPCODE_CLOSE = 8, WS_OPCODE_PING = 9, WS_OPCODE_PONG = 10 }; static bool ws_is_control_frame (int opcode) { return opcode >= WS_OPCODE_CLOSE; } struct ws_parser { struct str input; ///< External input buffer enum ws_parser_state state; ///< Parsing state unsigned is_fin : 1; ///< Final frame of a message? unsigned is_masked : 1; ///< Is the frame masked? unsigned reserved_1 : 1; ///< Reserved unsigned reserved_2 : 1; ///< Reserved unsigned reserved_3 : 1; ///< Reserved enum ws_opcode opcode; ///< Opcode uint32_t mask; ///< Frame mask uint64_t payload_len; ///< Payload length bool (*on_frame_header) (void *user_data, const struct ws_parser *self); /// Callback for when a message is successfully parsed. /// The actual payload is stored in "input", of length "payload_len". bool (*on_frame) (void *user_data, const struct ws_parser *self); void *user_data; ///< User data for callbacks }; static void ws_parser_init (struct ws_parser *self) { memset (self, 0, sizeof *self); str_init (&self->input); } static void ws_parser_free (struct ws_parser *self) { str_free (&self->input); } static void ws_parser_unmask (struct ws_parser *self) { // Yes, this could be made faster. For example by reading the mask in // native byte ordering and applying it directly here. uint64_t end = self->payload_len & ~(uint64_t) 3; for (uint64_t i = 0; i < end; i += 4) { self->input.str[i + 3] ^= self->mask & 0xFF; self->input.str[i + 2] ^= (self->mask >> 8) & 0xFF; self->input.str[i + 1] ^= (self->mask >> 16) & 0xFF; self->input.str[i ] ^= (self->mask >> 24) & 0xFF; } switch (self->payload_len - end) { case 3: self->input.str[end + 2] ^= (self->mask >> 8) & 0xFF; case 2: self->input.str[end + 1] ^= (self->mask >> 16) & 0xFF; case 1: self->input.str[end ] ^= (self->mask >> 24) & 0xFF; break; } } static bool ws_parser_push (struct ws_parser *self, const void *data, size_t len) { str_append_data (&self->input, data, len); struct msg_unpacker unpacker; msg_unpacker_init (&unpacker, self->input.str, self->input.len); while (true) switch (self->state) { uint8_t u8; uint16_t u16; case WS_PARSER_FIXED: if (self->input.len < 2) return true; (void) msg_unpacker_u8 (&unpacker, &u8); self->is_fin = (u8 >> 7) & 1; self->reserved_1 = (u8 >> 6) & 1; self->reserved_2 = (u8 >> 5) & 1; self->reserved_3 = (u8 >> 4) & 1; self->opcode = u8 & 15; (void) msg_unpacker_u8 (&unpacker, &u8); self->is_masked = (u8 >> 7) & 1; self->payload_len = u8 & 127; if (self->payload_len == 127) self->state = WS_PARSER_PAYLOAD_LEN_64; else if (self->payload_len == 126) self->state = WS_PARSER_PAYLOAD_LEN_16; else self->state = WS_PARSER_MASK; str_remove_slice (&self->input, 0, 2); break; case WS_PARSER_PAYLOAD_LEN_16: if (self->input.len < 2) return true; (void) msg_unpacker_u16 (&unpacker, &u16); self->payload_len = u16; self->state = WS_PARSER_MASK; str_remove_slice (&self->input, 0, 2); break; case WS_PARSER_PAYLOAD_LEN_64: if (self->input.len < 8) return true; (void) msg_unpacker_u64 (&unpacker, &self->payload_len); self->state = WS_PARSER_MASK; str_remove_slice (&self->input, 0, 8); break; case WS_PARSER_MASK: if (!self->is_masked) goto end_of_header; if (self->input.len < 4) return true; (void) msg_unpacker_u32 (&unpacker, &self->mask); str_remove_slice (&self->input, 0, 4); end_of_header: self->state = WS_PARSER_PAYLOAD; if (!self->on_frame_header (self->user_data, self)) return false; break; case WS_PARSER_PAYLOAD: if (self->input.len < self->payload_len) return true; if (self->is_masked) ws_parser_unmask (self); if (!self->on_frame (self->user_data, self)) return false; self->state = WS_PARSER_FIXED; str_reset (&self->input); break; } } // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - // TODO: something to build frames for data // - - Server handler - - - - - - - - - - - - - - - - - - - - - - - - - - - - - // WebSockets aren't CGI-compatible, therefore we must handle the initial HTTP // handshake ourselves. Luckily it's not too much of a bother with http-parser. // Typically there will be a normal HTTP server in front of us, proxying the // requests based on the URI. enum ws_handler_state { WS_HANDLER_HANDSHAKE, ///< Parsing HTTP WS_HANDLER_WEBSOCKETS ///< Parsing WebSockets frames }; struct ws_handler { enum ws_handler_state state; ///< State http_parser hp; ///< HTTP parser bool parsing_header_value; ///< Parsing header value or field? struct str field; ///< Field part buffer struct str value; ///< Value part buffer struct str_map headers; ///< HTTP Headers struct str url; ///< Request URL struct ws_parser parser; ///< Protocol frame parser bool expecting_continuation; ///< For non-control traffic enum ws_opcode message_opcode; ///< Opcode for the current message struct str message_data; ///< Concatenated message data unsigned ping_interval; ///< Ping interval in seconds uint64_t max_payload_len; ///< Maximum length of any message // TODO: bool closing; // XXX: rather a { OPEN, CLOSING } state? // TODO: a close timer // TODO: a ping timer (when no pong is received by the second time the // timer triggers, it is a ping timeout) ev_timer ping_timer; ///< Ping timer bool received_pong; ///< Received PONG since the last PING /// Called upon reception of a single full message bool (*on_message) (void *user_data, enum ws_opcode type, const void *data, size_t len); // TODO: void (*on_initialized) () that will allow the user to choose // any sub-protocol, if the client has provided any. /// The connection has been closed. /// @a close_code may, or may not, be one of enum ws_status. // NOTE: the "close_code" is what we receive from the remote endpoint, // or one of 1005/1006/1015 // NOTE: the reason is an empty string if omitted // TODO; also note that ideally, the handler should (be able to) first // receive a notification about the connection being closed because of // an error (recv()) returns -1, and call on_close() in reaction. void (*on_close) (void *user_data, int close_code, const char *reason); /// Write a chunk of data to the stream void (*write_cb) (void *user_data, const void *data, size_t len); // TODO: close_cb void *user_data; ///< User data for callbacks }; static void ws_handler_send_control (struct ws_handler *self, enum ws_opcode opcode, const void *data, size_t len) { if (len > WS_MAX_CONTROL_PAYLOAD_LEN) { print_debug ("truncating output control frame payload" " from %zu to %zu bytes", len, (size_t) WS_MAX_CONTROL_PAYLOAD_LEN); len = WS_MAX_CONTROL_PAYLOAD_LEN; } uint8_t header[2] = { 0x80 | (opcode & 0x0F), len }; self->write_cb (self->user_data, header, sizeof header); self->write_cb (self->user_data, data, len); } static void ws_handler_fail (struct ws_handler *self, enum ws_status reason) { uint8_t payload[2] = { reason << 8, reason }; ws_handler_send_control (self, WS_OPCODE_CLOSE, payload, sizeof payload); // TODO: set the close timer, ignore all further incoming input (either set // some flag for the case that we're in the middle of ws_handler_push(), // and/or add a mechanism to stop the caller from polling the socket for // reads). } // TODO: ws_handler_close() that behaves like ws_handler_fail() but doesn't // ignore frames up to a corresponding close from the client. // Read the RFC once again to see if we can really process the frames. static bool ws_handler_on_frame_header (void *user_data, const struct ws_parser *parser) { struct ws_handler *self = user_data; if (parser->reserved_1 || parser->reserved_2 || parser->reserved_3 || !parser->is_masked // client -> server payload must be masked || (ws_is_control_frame (parser->opcode) && (!parser->is_fin || parser->payload_len > WS_MAX_CONTROL_PAYLOAD_LEN)) || (!ws_is_control_frame (parser->opcode) && (self->expecting_continuation && parser->opcode != WS_OPCODE_CONT))) ws_handler_fail (self, WS_STATUS_PROTOCOL); else if (parser->payload_len > self->max_payload_len) ws_handler_fail (self, WS_STATUS_TOO_BIG); else return true; return false; } static bool ws_handler_on_control_frame (struct ws_handler *self, const struct ws_parser *parser) { switch (parser->opcode) { case WS_OPCODE_CLOSE: // TODO: confirm the close break; case WS_OPCODE_PING: ws_handler_send_control (self, WS_OPCODE_PONG, parser->input.str, parser->payload_len); break; case WS_OPCODE_PONG: // XXX: maybe we should check the payload self->received_pong = true; break; default: // TODO: shouldn't we rather fail on unknown control frames? // But should we actually return false at any time? Yes? break; } return true; } static bool ws_handler_on_frame (void *user_data, const struct ws_parser *parser) { struct ws_handler *self = user_data; if (ws_is_control_frame (parser->opcode)) return ws_handler_on_control_frame (self, parser); // TODO: do this rather in "on_frame_header" if (self->message_data.len + parser->payload_len > self->max_payload_len) { ws_handler_fail (self, WS_STATUS_TOO_BIG); return true; } if (!self->expecting_continuation) self->message_opcode = parser->opcode; str_append_data (&self->message_data, parser->input.str, parser->payload_len); self->expecting_continuation = !parser->is_fin; if (!parser->is_fin) return true; bool result = self->on_message (self->user_data, self->message_opcode, self->parser.input.str, self->parser.payload_len); str_reset (&self->message_data); return result; } static void ws_handler_on_ping_timer (EV_P_ ev_timer *watcher, int revents) { (void) loop; (void) revents; struct ws_handler *self = watcher->data; if (!self->received_pong) { // TODO: close/fail the connection? return; } ws_handler_send_control (self, WS_OPCODE_PING, NULL, 0); } static void ws_handler_init (struct ws_handler *self) { memset (self, 0, sizeof *self); http_parser_init (&self->hp, HTTP_REQUEST); self->hp.data = self; str_init (&self->field); str_init (&self->value); str_map_init (&self->headers); self->headers.free = free; self->headers.key_xfrm = tolower_ascii_strxfrm; str_init (&self->url); ws_parser_init (&self->parser); self->parser.on_frame_header = ws_handler_on_frame_header; self->parser.on_frame = ws_handler_on_frame; str_init (&self->message_data); self->ping_interval = 60; // This is still ridiculously high self->max_payload_len = UINT32_MAX; // Just so we can safely stop it ev_timer_init (&self->ping_timer, ws_handler_on_ping_timer, 0., 0.); self->ping_timer.data = self; // So that the first ping timer doesn't timeout the connection self->received_pong = true; } static void ws_handler_free (struct ws_handler *self) { str_free (&self->field); str_free (&self->value); str_map_free (&self->headers); str_free (&self->url); ws_parser_free (&self->parser); str_free (&self->message_data); ev_timer_stop (EV_DEFAULT_ &self->ping_timer); } static void ws_handler_on_header_read (struct ws_handler *self) { // TODO: some headers can appear more than once, concatenate their values; // for example "Sec-WebSocket-Version" str_map_set (&self->headers, self->field.str, self->value.str); } static int ws_handler_on_header_field (http_parser *parser, const char *at, size_t len) { struct ws_handler *self = parser->data; if (self->parsing_header_value) { ws_handler_on_header_read (self); str_reset (&self->field); str_reset (&self->value); } str_append_data (&self->field, at, len); self->parsing_header_value = false; return 0; } static int ws_handler_on_header_value (http_parser *parser, const char *at, size_t len) { struct ws_handler *self = parser->data; str_append_data (&self->value, at, len); self->parsing_header_value = true; return 0; } static int ws_handler_on_headers_complete (http_parser *parser) { // We strictly require a protocol upgrade if (!parser->upgrade) return 2; return 0; } static int ws_handler_on_url (http_parser *parser, const char *at, size_t len) { struct ws_handler *self = parser->data; str_append_data (&self->value, at, len); return 0; } static bool ws_handler_finish_handshake (struct ws_handler *self) { // TODO: probably factor this block out into its own function // TODO: check if everything seems to be right if (self->hp.method != HTTP_GET || self->hp.http_major != 1 || self->hp.http_minor != 1) ; // TODO: error (maybe send a frame depending on conditions) // ...mostly just 400 Bad Request const char *upgrade = str_map_find (&self->headers, "Upgrade"); const char *key = str_map_find (&self->headers, SEC_WS_KEY); const char *version = str_map_find (&self->headers, SEC_WS_VERSION); const char *protocol = str_map_find (&self->headers, SEC_WS_PROTOCOL); if (!upgrade || strcmp (upgrade, "websocket") || !version || strcmp (version, "13")) ; // TODO: error // ... if the version doesn't match, we must send back a header indicating // the version we do support struct str response; str_init (&response); str_append (&response, "HTTP/1.1 101 Switching Protocols\r\n"); str_append (&response, "Upgrade: websocket\r\n"); str_append (&response, "Connection: Upgrade\r\n"); // TODO: prepare the rest of the headers // TODO: we should ideally check that this is a 16-byte base64-encoded value char *response_key = ws_encode_response_key (key); str_append_printf (&response, SEC_WS_ACCEPT ": %s\r\n", response_key); free (response_key); str_append (&response, "\r\n"); self->write_cb (self->user_data, response.str, response.len); str_free (&response); // XXX: maybe we should start it earlier so that the handshake can // timeout as well. ws_handler_connected()? ev_timer_start (EV_DEFAULT_ &self->ping_timer); return true; } static bool ws_handler_push (struct ws_handler *self, const void *data, size_t len) { if (self->state == WS_HANDLER_WEBSOCKETS) return ws_parser_push (&self->parser, data, len); // The handshake hasn't been done yet, process HTTP headers static const http_parser_settings http_settings = { .on_header_field = ws_handler_on_header_field, .on_header_value = ws_handler_on_header_value, .on_headers_complete = ws_handler_on_headers_complete, .on_url = ws_handler_on_url, }; size_t n_parsed = http_parser_execute (&self->hp, &http_settings, data, len); if (self->hp.upgrade) { if (len - n_parsed) { // TODO: error: the handshake hasn't been finished, yet there // is more data to process after the headers } if (!ws_handler_finish_handshake (self)) return false; self->state = WS_HANDLER_WEBSOCKETS; return true; } if (n_parsed != len || HTTP_PARSER_ERRNO (&self->hp) != HPE_OK) { // TODO: error // print_debug (..., http_errno_description // (HTTP_PARSER_ERRNO (&self->hp)); // NOTE: if == HPE_CB_headers_complete, "Upgrade" is missing return false; } return true; } // --- Server ------------------------------------------------------------------ static struct config_item g_config_table[] = { { "bind_host", NULL, "Address of the server" }, { "port_fastcgi", "9000", "Port to bind for FastCGI" }, { "port_scgi", NULL, "Port to bind for SCGI" }, { "port_ws", NULL, "Port to bind for WebSockets" }, { "pid_file", NULL, "Full path for the PID file" }, // XXX: here belongs something like a web SPA that interfaces with us { "static_root", NULL, "The root for static content" }, { NULL, NULL, NULL } }; struct server_context { ev_signal sigterm_watcher; ///< Got SIGTERM ev_signal sigint_watcher; ///< Got SIGINT bool quitting; ///< User requested quitting struct listener *listeners; ///< Listeners size_t n_listeners; ///< Number of listening sockets struct client *clients; ///< Clients unsigned n_clients; ///< Current number of connections struct request_handler *handlers; ///< Request handlers struct str_map config; ///< Server configuration }; static void server_context_init (struct server_context *self) { memset (self, 0, sizeof *self); str_map_init (&self->config); load_config_defaults (&self->config, g_config_table); } static void close_listeners (struct server_context *self); static void server_context_free (struct server_context *self) { // We really shouldn't attempt a quit without closing the clients first soft_assert (!self->clients); close_listeners (self); free (self->listeners); str_map_free (&self->config); } // --- JSON-RPC ---------------------------------------------------------------- #define JSON_RPC_ERROR_TABLE(XX) \ XX (-32700, PARSE_ERROR, "Parse error") \ XX (-32600, INVALID_REQUEST, "Invalid Request") \ XX (-32601, METHOD_NOT_FOUND, "Method not found") \ XX (-32602, INVALID_PARAMS, "Invalid params") \ XX (-32603, INTERNAL_ERROR, "Internal error") enum json_rpc_error { #define XX(code, name, message) JSON_RPC_ERROR_ ## name, JSON_RPC_ERROR_TABLE (XX) #undef XX JSON_RPC_ERROR_COUNT }; static json_t * json_rpc_error (enum json_rpc_error id, json_t *data) { #define XX(code, name, message) { code, message }, static const struct json_rpc_error { int code; const char *message; } errors[JSON_RPC_ERROR_COUNT] = { JSON_RPC_ERROR_TABLE (XX) }; #undef XX json_t *error = json_object (); json_object_set_new (error, "code", json_integer (errors[id].code)); json_object_set_new (error, "message", json_string (errors[id].message)); if (data) json_object_set_new (error, "data", data); return error; } static json_t * json_rpc_response (json_t *id, json_t *result, json_t *error) { json_t *x = json_object (); json_object_set_new (x, "jsonrpc", json_string ("2.0")); json_object_set_new (x, "id", id ? id : json_null ()); if (result) json_object_set_new (x, "result", result); if (error) json_object_set_new (x, "error", error); return x; } // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - static bool try_advance (const char **p, const char *text) { size_t len = strlen (text); if (strncmp (*p, text, len)) return false; *p += len; return true; } static bool validate_json_rpc_content_type (const char *type) { const char *content_types[] = { "application/json-rpc", // obsolete "application/json" }; const char *tails[] = { "; charset=utf-8", "; charset=UTF-8", "" }; bool found = false; for (size_t i = 0; i < N_ELEMENTS (content_types); i++) if ((found = try_advance (&type, content_types[i]))) break; if (!found) return false; for (size_t i = 0; i < N_ELEMENTS (tails); i++) if ((found = try_advance (&type, tails[i]))) break; if (!found) return false; return !*type; } // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - typedef json_t *(*json_rpc_handler_fn) (struct server_context *, json_t *); struct json_rpc_handler_info { const char *method_name; ///< JSON-RPC method name json_rpc_handler_fn handler; ///< Method handler }; static int json_rpc_handler_info_cmp (const void *first, const void *second) { return strcmp (((struct json_rpc_handler_info *) first)->method_name, ((struct json_rpc_handler_info *) second)->method_name); } // TODO: a method that queues up a ping over IRC: this has to be owned by the // server context as a background job that removes itself upon completion. static json_t * json_rpc_ping (struct server_context *ctx, json_t *params) { (void) ctx; (void) params; return json_rpc_response (NULL, json_string ("pong"), NULL); } static json_t * process_json_rpc_request (struct server_context *ctx, json_t *request) { // A list of all available methods; this list has to be ordered. // Eventually it might be better to move this into a map in the context. static struct json_rpc_handler_info handlers[] = { { "ping", json_rpc_ping }, }; if (!json_is_object (request)) return json_rpc_response (NULL, NULL, json_rpc_error (JSON_RPC_ERROR_INVALID_REQUEST, NULL)); json_t *v = json_object_get (request, "jsonrpc"); json_t *m = json_object_get (request, "method"); json_t *params = json_object_get (request, "params"); json_t *id = json_object_get (request, "id"); const char *version; const char *method; bool ok = true; ok &= v && (version = json_string_value (v)) && !strcmp (version, "2.0"); ok &= m && (method = json_string_value (m)); ok &= !params || json_is_array (params) || json_is_object (params); ok &= !id || json_is_null (id) || json_is_string (id) || json_is_number (id); if (!ok) return json_rpc_response (id, NULL, json_rpc_error (JSON_RPC_ERROR_INVALID_REQUEST, NULL)); struct json_rpc_handler_info key = { .method_name = method }; struct json_rpc_handler_info *handler = bsearch (&key, handlers, N_ELEMENTS (handlers), sizeof key, json_rpc_handler_info_cmp); if (!handler) return json_rpc_response (id, NULL, json_rpc_error (JSON_RPC_ERROR_METHOD_NOT_FOUND, NULL)); json_t *response = handler->handler (ctx, params); if (id) return response; // Notifications don't get responses json_decref (response); return NULL; } static void flush_json (json_t *json, struct str *output) { char *utf8 = json_dumps (json, JSON_ENCODE_ANY); str_append (output, utf8); free (utf8); json_decref (json); } static void process_json_rpc (struct server_context *ctx, const void *data, size_t len, struct str *output) { json_error_t e; json_t *request; if (!(request = json_loadb (data, len, JSON_DECODE_ANY, &e))) { flush_json (json_rpc_response (NULL, NULL, json_rpc_error (JSON_RPC_ERROR_PARSE_ERROR, NULL)), output); return; } if (json_is_array (request)) { if (!json_array_size (request)) { flush_json (json_rpc_response (NULL, NULL, json_rpc_error (JSON_RPC_ERROR_INVALID_REQUEST, NULL)), output); return; } json_t *response = json_array (); json_t *iter; size_t i; json_array_foreach (request, i, iter) { json_t *result = process_json_rpc_request (ctx, iter); if (result) json_array_append_new (response, result); } if (json_array_size (response)) flush_json (response, output); else json_decref (response); } else { json_t *result = process_json_rpc_request (ctx, request); if (result) flush_json (result, output); } } // --- Requests ---------------------------------------------------------------- struct request { struct server_context *ctx; ///< Server context struct request_handler *handler; ///< Current request handler void *handler_data; ///< User data for the handler /// Callback to write some CGI response data to the output void (*write_cb) (void *user_data, const void *data, size_t len); /// Callback to close the connection. /// CALLING THIS MAY CAUSE THE REQUEST TO BE DESTROYED. void (*close_cb) (void *user_data); void *user_data; ///< User data argument for callbacks }; struct request_handler { LIST_HEADER (struct request_handler) /// Install ourselves as the handler for the request if applicable. /// Set @a continue_ to false if further processing should be stopped. bool (*try_handle) (struct request *request, struct str_map *headers, bool *continue_); /// Handle incoming data. /// Return false if further processing should be stopped. bool (*push_cb) (struct request *request, const void *data, size_t len); /// Destroy the handler void (*destroy_cb) (struct request *request); }; static void request_init (struct request *self) { memset (self, 0, sizeof *self); } static void request_free (struct request *self) { if (self->handler) self->handler->destroy_cb (self); } /// This function is only intended to be run from asynchronous event handlers /// such as timers, not as a direct result of starting the request or receiving /// request data. CALLING THIS MAY CAUSE THE REQUEST TO BE DESTROYED. static void request_finish (struct request *self) { self->close_cb (self->user_data); } static bool request_start (struct request *self, struct str_map *headers) { // XXX: it feels like this should rather be two steps: // bool (*can_handle) (request *, headers) // ... install the handler ... // bool (*handle) (request *) // // However that might cause some stuff to be done twice. // // Another way we could get rid off the continue_ argument is via adding // some way of marking the request as finished from within the handler. bool continue_ = true; LIST_FOR_EACH (struct request_handler, handler, self->ctx->handlers) if (handler->try_handle (self, headers, &continue_)) { self->handler = handler; return continue_; } // Unable to serve the request struct str response; str_init (&response); str_append (&response, "Status: 404 Not Found\n"); str_append (&response, "Content-Type: text/plain\n\n"); self->write_cb (self->user_data, response.str, response.len); str_free (&response); return false; } static bool request_push (struct request *self, const void *data, size_t len) { if (!soft_assert (self->handler)) // No handler, nothing to do with any data return false; return self->handler->push_cb (self, data, len); } // --- Requests handlers ------------------------------------------------------- static bool request_handler_json_rpc_try_handle (struct request *request, struct str_map *headers, bool *continue_) { const char *content_type = str_map_find (headers, "CONTENT_TYPE"); const char *method = str_map_find (headers, "REQUEST_METHOD"); if (!method || strcmp (method, "POST") || !content_type || !validate_json_rpc_content_type (content_type)) return false; struct str *buf = xcalloc (1, sizeof *buf); str_init (buf); request->handler_data = buf; *continue_ = true; return true; } static bool request_handler_json_rpc_push (struct request *request, const void *data, size_t len) { struct str *buf = request->handler_data; if (len) { str_append_data (buf, data, len); return true; } struct str response; str_init (&response); str_append (&response, "Status: 200 OK\n"); str_append_printf (&response, "Content-Type: %s\n\n", "application/json"); process_json_rpc (request->ctx, buf->str, buf->len, &response); request->write_cb (request->user_data, response.str, response.len); str_free (&response); return false; } static void request_handler_json_rpc_destroy (struct request *request) { struct str *buf = request->handler_data; str_free (buf); free (buf); request->handler_data = NULL; } struct request_handler g_request_handler_json_rpc = { .try_handle = request_handler_json_rpc_try_handle, .push_cb = request_handler_json_rpc_push, .destroy_cb = request_handler_json_rpc_destroy, }; // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - static char * canonicalize_url_path (const char *path) { struct str_vector v; str_vector_init (&v); split_str_ignore_empty (path, '/', &v); struct str_vector canonical; str_vector_init (&canonical); // So that the joined path always begins with a slash str_vector_add (&canonical, ""); for (size_t i = 0; i < v.len; i++) { const char *dir = v.vector[i]; if (!strcmp (dir, ".")) continue; if (strcmp (dir, "..")) str_vector_add (&canonical, dir); else if (canonical.len) // ".." never goes above the root str_vector_remove (&canonical, canonical.len - 1); } str_vector_free (&v); char *joined = join_str_vector (&canonical, '/'); str_vector_free (&canonical); return joined; } static char * detect_magic (const void *data, size_t len) { magic_t cookie; char *mime_type = NULL; if (!(cookie = magic_open (MAGIC_MIME))) return NULL; const char *magic = NULL; if (!magic_load (cookie, NULL) && (magic = magic_buffer (cookie, data, len))) mime_type = xstrdup (magic); else print_debug ("MIME type detection failed: %s", magic_error (cookie)); magic_close (cookie); return mime_type; } static bool request_handler_static_try_handle (struct request *request, struct str_map *headers, bool *continue_) { // Serving static files is actually quite complicated as it turns out; // but this is only meant to serve a few tiny text files struct server_context *ctx = request->ctx; const char *root = str_map_find (&ctx->config, "static_root"); if (!root) { print_debug ("static document root not configured"); return false; } const char *method = str_map_find (headers, "REQUEST_METHOD"); if (!method || strcmp (method, "GET")) return false; // TODO: look at , REQUEST_URI in the headers const char *path_info = str_map_find (headers, "PATH_INFO"); if (!path_info) { print_debug ("PATH_INFO not defined"); return false; } // We need to filter the path to stay in our root // Being able to read /etc/passwd would be rather embarrasing char *suffix = canonicalize_url_path (path_info); char *path = xstrdup_printf ("%s%s", root, suffix); // TODO: check that this is a regular file FILE *fp = fopen (path, "rb"); if (!fp) { struct str response; str_init (&response); str_append (&response, "Status: 404 Not Found\n"); str_append (&response, "Content-Type: text/plain\n\n"); str_append_printf (&response, "File %s was not found on this server\n", suffix); request->write_cb (request->user_data, response.str, response.len); str_free (&response); free (suffix); free (path); return false; } free (suffix); free (path); uint8_t buf[8192]; size_t len; // Try to detect the Content-Type from the actual contents char *mime_type = NULL; if ((len = fread (buf, 1, sizeof buf, fp))) mime_type = detect_magic (buf, len); if (!mime_type) mime_type = xstrdup ("application/octet_stream"); struct str response; str_init (&response); str_append (&response, "Status: 200 OK\n"); str_append_printf (&response, "Content-Type: %s\n\n", mime_type); request->write_cb (request->user_data, response.str, response.len); str_free (&response); free (mime_type); // Write the chunk we've used to help us with magic detection; // obviously we have to do it after we've written the headers if (len) request->write_cb (request->user_data, buf, len); while ((len = fread (buf, 1, sizeof buf, fp))) request->write_cb (request->user_data, buf, len); fclose (fp); // TODO: this should rather not be returned all at once but in chunks; // file read requests never return EAGAIN // TODO: actual file data should really be returned by a callback when // the socket is writable with nothing to be sent (pumping the entire // file all at once won't really work if it's huge). *continue_ = false; return true; } static bool request_handler_static_push (struct request *request, const void *data, size_t len) { (void) request; (void) data; (void) len; // Ignoring all content; we shouldn't receive any (GET) return false; } static void request_handler_static_destroy (struct request *request) { (void) request; } struct request_handler g_request_handler_static = { .try_handle = request_handler_static_try_handle, .push_cb = request_handler_static_push, .destroy_cb = request_handler_static_destroy, }; // --- Client communication handlers ------------------------------------------- struct client { LIST_HEADER (struct client) struct server_context *ctx; ///< Server context int socket_fd; ///< The TCP socket write_queue_t write_queue; ///< Write queue ev_io read_watcher; ///< The socket can be read from ev_io write_watcher; ///< The socket can be written to struct client_impl *impl; ///< Client behaviour void *impl_data; ///< Client behaviour data }; struct client_impl { /// Initialize the client as needed void (*init) (struct client *client); // TODO: a method for graceful shutdown which will, in the case of // WebSockets, actually send a "shutdown" close packet, and in the case // of FastCGI will FCGI_END_REQUEST everything with FCGI_REQUEST_COMPLETE // and FCGI_OVERLOADED all incoming requests in the meantime (the FastCGI // specification isn't very clear about how we should respond to this). // // We then should set up a timer for about a second until we kill all // clients for good. /// Do any additional cleanup void (*destroy) (struct client *client); /// Process incoming data; "len == 0" means EOF bool (*push) (struct client *client, const void *data, size_t len); }; static void client_init (struct client *self) { memset (self, 0, sizeof *self); write_queue_init (&self->write_queue); } static void client_free (struct client *self) { write_queue_free (&self->write_queue); } static void client_write (struct client *client, const void *data, size_t len) { write_req_t *req = xcalloc (1, sizeof *req); req->data.iov_base = memcpy (xmalloc (len), data, len); req->data.iov_len = len; write_queue_add (&client->write_queue, req); ev_io_start (EV_DEFAULT_ &client->write_watcher); } static void client_remove (struct client *client) { struct server_context *ctx = client->ctx; LIST_UNLINK (ctx->clients, client); ctx->n_clients--; // First uninitialize the higher-level implementation client->impl->destroy (client); ev_io_stop (EV_DEFAULT_ &client->read_watcher); ev_io_stop (EV_DEFAULT_ &client->write_watcher); xclose (client->socket_fd); client_free (client); free (client); } // - - FastCGI - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - struct client_fcgi { struct fcgi_muxer muxer; ///< FastCGI de/multiplexer }; struct client_fcgi_request { struct fcgi_request *fcgi_request; ///< FastCGI request struct request request; ///< Request }; static void client_fcgi_request_write (void *user_data, const void *data, size_t len) { struct client_fcgi_request *request = user_data; fcgi_request_write (request->fcgi_request, data, len); } static void client_fcgi_request_close (void *user_data) { struct client_fcgi_request *request = user_data; // TODO: fcgi_request_finish()? That will most probably end up with us // receiving client_fcgi_request_destroy() } static void * client_fcgi_request_start (void *user_data, struct fcgi_request *fcgi_request) { struct client *client = user_data; // TODO: what if the request is aborted by ; struct client_fcgi_request *request = xmalloc (sizeof *request); request->fcgi_request = fcgi_request; request_init (&request->request); request->request.ctx = client->ctx; request->request.write_cb = client_fcgi_request_write; request->request.close_cb = client_fcgi_request_close; request->request.user_data = request; return request; } static void client_fcgi_request_push (void *handler_data, const void *data, size_t len) { struct client_fcgi_request *request = handler_data; request_push (&request->request, data, len); } static void client_fcgi_request_destroy (void *handler_data) { struct client_fcgi_request *request = handler_data; request_free (&request->request); free (handler_data); } static void client_fcgi_write (void *user_data, const void *data, size_t len) { struct client *client = user_data; client_write (client, data, len); } static void client_fcgi_close (void *user_data) { struct client *client = user_data; client_remove (client); } static void client_fcgi_init (struct client *client) { struct client_fcgi *self = xcalloc (1, sizeof *self); client->impl_data = self; fcgi_muxer_init (&self->muxer); self->muxer.write_cb = client_fcgi_write; self->muxer.close_cb = client_fcgi_close; self->muxer.request_start_cb = client_fcgi_request_start; self->muxer.request_push_cb = client_fcgi_request_push; self->muxer.request_destroy_cb = client_fcgi_request_destroy; self->muxer.user_data = client; } static void client_fcgi_destroy (struct client *client) { struct client_fcgi *self = client->impl_data; client->impl_data = NULL; fcgi_muxer_free (&self->muxer); free (self); } static bool client_fcgi_push (struct client *client, const void *data, size_t len) { struct client_fcgi *self = client->impl_data; fcgi_muxer_push (&self->muxer, data, len); return true; } static struct client_impl g_client_fcgi = { .init = client_fcgi_init, .destroy = client_fcgi_destroy, .push = client_fcgi_push, }; // - - SCGI - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - struct client_scgi { struct scgi_parser parser; ///< SCGI stream parser struct request request; ///< Request (only one per connection) }; static void client_scgi_write (void *user_data, const void *data, size_t len) { struct client *client = user_data; client_write (client, data, len); } static void client_scgi_close (void *user_data) { // NOTE: this rather really means "close me [the request]" struct client *client = user_data; client_remove (client); } static bool client_scgi_on_headers_read (void *user_data) { struct client *client = user_data; struct client_scgi *self = client->impl_data; return request_start (&self->request, &self->parser.headers); } static bool client_scgi_on_content (void *user_data, const void *data, size_t len) { struct client *client = user_data; struct client_scgi *self = client->impl_data; // XXX: do we have to count CONTENT_LENGTH and supply our own EOF? // If we do produce our own EOF, we should probably make sure we don't // send it twice in a row. return request_push (&self->request, data, len); } static void client_scgi_init (struct client *client) { struct client_scgi *self = xcalloc (1, sizeof *self); client->impl_data = self; request_init (&self->request); self->request.ctx = client->ctx; self->request.write_cb = client_scgi_write; self->request.close_cb = client_scgi_close; self->request.user_data = client; scgi_parser_init (&self->parser); self->parser.on_headers_read = client_scgi_on_headers_read; self->parser.on_content = client_scgi_on_content; self->parser.user_data = client; } static void client_scgi_destroy (struct client *client) { struct client_scgi *self = client->impl_data; client->impl_data = NULL; request_free (&self->request); scgi_parser_free (&self->parser); free (self); } static bool client_scgi_push (struct client *client, const void *data, size_t len) { struct client_scgi *self = client->impl_data; struct error *e = NULL; if (scgi_parser_push (&self->parser, data, len, &e)) return true; if (e != NULL) { print_debug ("SCGI parser failed: %s", e->message); error_free (e); } return false; } static struct client_impl g_client_scgi = { .init = client_scgi_init, .destroy = client_scgi_destroy, .push = client_scgi_push, }; // - - WebSockets - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - struct client_ws { struct ws_handler handler; ///< WebSockets connection handler }; static void client_ws_write (void *user_data, const void *data, size_t len) { struct client *client = user_data; client_write (client, data, len); } static bool client_ws_on_message (void *user_data, enum ws_opcode type, const void *data, size_t len) { struct client *client = user_data; struct client_ws *self = client->impl_data; struct str response; str_init (&response); process_json_rpc (client->ctx, data, len, &response); // TODO: send the response str_free (&response); return true; } static void client_ws_init (struct client *client) { struct client_ws *self = xmalloc (sizeof *self); client->impl_data = self; ws_handler_init (&self->handler); self->handler.write_cb = client_ws_write; self->handler.on_message = client_ws_on_message; self->handler.user_data = client; // TODO: configure the handler some more, e.g. regarding the protocol } static void client_ws_destroy (struct client *client) { struct client_ws *self = client->impl_data; client->impl_data = NULL; ws_handler_free (&self->handler); free (self); } static bool client_ws_push (struct client *client, const void *data, size_t len) { struct client_ws *self = client->impl_data; return ws_handler_push (&self->handler, data, len); } static struct client_impl g_client_ws = { .init = client_ws_init, .destroy = client_ws_destroy, .push = client_ws_push, }; // --- Basic server stuff ------------------------------------------------------ struct listener { int fd; ///< Listening socket FD ev_io watcher; ///< New connection available struct client_impl *impl; ///< Client behaviour }; static void close_listeners (struct server_context *self) { // TODO: factor out the closing act, to be used in initiate_quit() for (size_t i = 0; i < self->n_listeners; i++) { struct listener *listener = &self->listeners[i]; if (listener->fd == -1) continue; ev_io_stop (EV_DEFAULT_ &listener->watcher); xclose (listener->fd); listener->fd = -1; } } static bool client_read_loop (EV_P_ struct client *client, ev_io *watcher) { char buf[8192]; while (true) { ssize_t n_read = recv (watcher->fd, buf, sizeof buf, 0); if (n_read >= 0) { if (!client->impl->push (client, buf, n_read)) return false; if (!n_read) break; } else if (errno == EAGAIN) return true; else if (errno != EINTR) return false; } // Don't receive the EOF condition repeatedly ev_io_stop (EV_A_ watcher); // We can probably still write, so let's just return return true; } static void on_client_ready (EV_P_ ev_io *watcher, int revents) { struct client *client = watcher->data; if (revents & EV_READ) if (!client_read_loop (EV_A_ client, watcher)) goto close; if (revents & EV_WRITE) // TODO: shouldn't we at least provide an option (to be used by a client // implementation if it so desires) to close the connection once we've // finished flushing the write queue? This should probably even be // the default behaviour, as it's fairly uncommon for clients to // shutdown the socket for writes while leaving it open for reading. // TODO: some sort of "on_buffers_flushed" callback for streaming huge // chunks of external (or generated) data. if (!flush_queue (&client->write_queue, watcher)) goto close; return; close: client_remove (client); } static void make_client (EV_P_ struct client_impl *impl, int sock_fd) { struct server_context *ctx = ev_userdata (loop); set_blocking (sock_fd, false); struct client *client = xmalloc (sizeof *client); client_init (client); client->socket_fd = sock_fd; client->impl = impl; ev_io_init (&client->read_watcher, on_client_ready, sock_fd, EV_READ); ev_io_init (&client->write_watcher, on_client_ready, sock_fd, EV_WRITE); client->read_watcher.data = client; client->write_watcher.data = client; // We're only interested in reading as the write queue is empty now ev_io_start (EV_A_ &client->read_watcher); // Initialize the higher-level implementation client->impl->init (client); LIST_PREPEND (ctx->clients, client); ctx->n_clients++; } static void on_client_available (EV_P_ ev_io *watcher, int revents) { struct listener *listener = watcher->data; (void) revents; while (true) { int sock_fd = accept (watcher->fd, NULL, NULL); if (sock_fd != -1) make_client (EV_A_ listener->impl, sock_fd); else if (errno == EAGAIN) return; else if (errno != EINTR && errno != ECONNABORTED) break; } // Stop accepting connections to prevent busy looping ev_io_stop (EV_A_ watcher); print_fatal ("%s: %s", "accept", strerror (errno)); // TODO: initiate_quit (ctx); } // --- Application setup ------------------------------------------------------- /// This function handles values that require validation before their first use, /// or some kind of a transformation (such as conversion to an integer) needs /// to be done before they can be used directly. static bool parse_config (struct server_context *ctx, struct error **e) { (void) ctx; (void) e; return true; } static int listener_bind (struct addrinfo *gai_iter) { int fd = socket (gai_iter->ai_family, gai_iter->ai_socktype, gai_iter->ai_protocol); if (fd == -1) return -1; set_cloexec (fd); int yes = 1; soft_assert (setsockopt (fd, SOL_SOCKET, SO_KEEPALIVE, &yes, sizeof yes) != -1); soft_assert (setsockopt (fd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof yes) != -1); char host[NI_MAXHOST], port[NI_MAXSERV]; host[0] = port[0] = '\0'; int err = getnameinfo (gai_iter->ai_addr, gai_iter->ai_addrlen, host, sizeof host, port, sizeof port, NI_NUMERICHOST | NI_NUMERICSERV); if (err) print_debug ("%s: %s", "getnameinfo", gai_strerror (err)); char *address = format_host_port_pair (host, port); if (bind (fd, gai_iter->ai_addr, gai_iter->ai_addrlen)) print_error ("bind to %s failed: %s", address, strerror (errno)); else if (listen (fd, 16 /* arbitrary number */)) print_error ("listen on %s failed: %s", address, strerror (errno)); else { print_status ("listening on %s", address); free (address); return fd; } free (address); xclose (fd); return -1; } static void listener_add (struct server_context *ctx, const char *host, const char *port, const struct addrinfo *gai_hints, struct client_impl *impl) { struct addrinfo *gai_result, *gai_iter; int err = getaddrinfo (host, port, gai_hints, &gai_result); if (err) { char *address = format_host_port_pair (host, port); print_error ("bind to %s failed: %s: %s", address, "getaddrinfo", gai_strerror (err)); free (address); return; } int fd; for (gai_iter = gai_result; gai_iter; gai_iter = gai_iter->ai_next) { if ((fd = listener_bind (gai_iter)) == -1) continue; set_blocking (fd, false); struct listener *listener = &ctx->listeners[ctx->n_listeners++]; ev_io_init (&listener->watcher, on_client_available, fd, EV_READ); ev_io_start (EV_DEFAULT_ &listener->watcher); listener->watcher.data = listener; listener->impl = impl; break; } freeaddrinfo (gai_result); } static void get_ports_from_config (struct server_context *ctx, const char *key, struct str_vector *out) { const char *ports; if ((ports = str_map_find (&ctx->config, key))) split_str_ignore_empty (ports, ',', out); } static bool setup_listen_fds (struct server_context *ctx, struct error **e) { static const struct addrinfo gai_hints = { .ai_socktype = SOCK_STREAM, .ai_flags = AI_PASSIVE, }; struct str_vector ports_fcgi; str_vector_init (&ports_fcgi); struct str_vector ports_scgi; str_vector_init (&ports_scgi); struct str_vector ports_ws; str_vector_init (&ports_ws); get_ports_from_config (ctx, "port_fastcgi", &ports_fcgi); get_ports_from_config (ctx, "port_scgi", &ports_scgi); get_ports_from_config (ctx, "port_ws", &ports_ws); const char *bind_host = str_map_find (&ctx->config, "bind_host"); size_t n_ports = ports_fcgi.len + ports_scgi.len + ports_ws.len; ctx->listeners = xcalloc (n_ports, sizeof *ctx->listeners); for (size_t i = 0; i < ports_fcgi.len; i++) listener_add (ctx, bind_host, ports_fcgi.vector[i], &gai_hints, &g_client_fcgi); for (size_t i = 0; i < ports_scgi.len; i++) listener_add (ctx, bind_host, ports_scgi.vector[i], &gai_hints, &g_client_scgi); for (size_t i = 0; i < ports_ws.len; i++) listener_add (ctx, bind_host, ports_ws.vector[i], &gai_hints, &g_client_ws); str_vector_free (&ports_fcgi); str_vector_free (&ports_scgi); str_vector_free (&ports_ws); if (!ctx->n_listeners) { error_set (e, "%s: %s", "network setup failed", "no ports to listen on"); return false; } return true; } static bool lock_pid_file (struct server_context *ctx, struct error **e) { const char *path = str_map_find (&ctx->config, "pid_file"); if (!path) return true; int fd = open (path, O_RDWR | O_CREAT, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH /* 644 */); if (fd < 0) { error_set (e, "can't open `%s': %s", path, strerror (errno)); return false; } struct flock lock = { .l_type = F_WRLCK, .l_start = 0, .l_whence = SEEK_SET, .l_len = 0, }; if (fcntl (fd, F_SETLK, &lock)) { error_set (e, "can't lock `%s': %s", path, strerror (errno)); return false; } struct str pid; str_init (&pid); str_append_printf (&pid, "%ld", (long) getpid ()); if (ftruncate (fd, 0) || write (fd, pid.str, pid.len) != (ssize_t) pid.len) { error_set (e, "can't write to `%s': %s", path, strerror (errno)); return false; } str_free (&pid); // Intentionally not closing the file descriptor; it must stay alive // for the entire life of the application return true; } // --- Main program ------------------------------------------------------------ static void on_termination_signal (EV_P_ ev_signal *handle, int revents) { struct server_context *ctx = ev_userdata (loop); (void) handle; (void) revents; // TODO: initiate_quit (ctx); } static void daemonize (void) { print_status ("daemonizing..."); if (chdir ("/")) exit_fatal ("%s: %s", "chdir", strerror (errno)); pid_t pid; if ((pid = fork ()) < 0) exit_fatal ("%s: %s", "fork", strerror (errno)); else if (pid) exit (EXIT_SUCCESS); setsid (); signal (SIGHUP, SIG_IGN); if ((pid = fork ()) < 0) exit_fatal ("%s: %s", "fork", strerror (errno)); else if (pid) exit (EXIT_SUCCESS); openlog (PROGRAM_NAME, LOG_NDELAY | LOG_NOWAIT | LOG_PID, 0); g_log_message_real = log_message_syslog; // XXX: we may close our own descriptors this way, crippling ourselves; // there is no real guarantee that we will start with all three // descriptors open. In theory we could try to enumerate the descriptors // at the start of main(). for (int i = 0; i < 3; i++) xclose (i); int tty = open ("/dev/null", O_RDWR); if (tty != 0 || dup (0) != 1 || dup (0) != 2) exit_fatal ("failed to reopen FD's: %s", strerror (errno)); } static void parse_program_arguments (int argc, char **argv) { static const struct opt opts[] = { { 'd', "debug", NULL, 0, "run in debug mode" }, { 'h', "help", NULL, 0, "display this help and exit" }, { 'V', "version", NULL, 0, "output version information and exit" }, { 'w', "write-default-cfg", "FILENAME", OPT_OPTIONAL_ARG | OPT_LONG_ONLY, "write a default configuration file and exit" }, { 0, NULL, NULL, 0, NULL } }; struct opt_handler oh; opt_handler_init (&oh, argc, argv, opts, NULL, "JSON-RPC 2.0 demo server."); int c; while ((c = opt_handler_get (&oh)) != -1) switch (c) { case 'd': g_debug_mode = true; break; case 'h': opt_handler_usage (&oh, stdout); exit (EXIT_SUCCESS); case 'V': printf (PROGRAM_NAME " " PROGRAM_VERSION "\n"); exit (EXIT_SUCCESS); case 'w': call_write_default_config (optarg, g_config_table); exit (EXIT_SUCCESS); default: print_error ("wrong options"); opt_handler_usage (&oh, stderr); exit (EXIT_FAILURE); } argc -= optind; argv += optind; if (argc) { opt_handler_usage (&oh, stderr); exit (EXIT_FAILURE); } opt_handler_free (&oh); } int main (int argc, char *argv[]) { parse_program_arguments (argc, argv); print_status (PROGRAM_NAME " " PROGRAM_VERSION " starting"); struct server_context ctx; server_context_init (&ctx); struct error *e = NULL; if (!read_config_file (&ctx.config, &e)) { print_error ("error loading configuration: %s", e->message); error_free (e); exit (EXIT_FAILURE); } struct ev_loop *loop; if (!(loop = EV_DEFAULT)) exit_fatal ("libev initialization failed"); ev_set_userdata (loop, &ctx); ev_signal_init (&ctx.sigterm_watcher, on_termination_signal, SIGTERM); ev_signal_start (EV_DEFAULT_ &ctx.sigterm_watcher); ev_signal_init (&ctx.sigint_watcher, on_termination_signal, SIGINT); ev_signal_start (EV_DEFAULT_ &ctx.sigint_watcher); (void) signal (SIGPIPE, SIG_IGN); LIST_PREPEND (ctx.handlers, &g_request_handler_static); LIST_PREPEND (ctx.handlers, &g_request_handler_json_rpc); if (!parse_config (&ctx, &e) || !lock_pid_file (&ctx, &e) || !setup_listen_fds (&ctx, &e)) { print_error ("%s", e->message); error_free (e); exit (EXIT_FAILURE); } if (!g_debug_mode) daemonize (); ev_run (loop, 0); ev_loop_destroy (loop); server_context_free (&ctx); return EXIT_SUCCESS; }