/* * Copyright (c) 2002-2006 Niels Provos <provos@citi.umich.edu> * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #ifdef HAVE_SYS_PARAM_H #include <sys/param.h> #endif #ifdef HAVE_SYS_TYPES_H #include <sys/types.h> #endif #ifdef HAVE_SYS_TIME_H #include <sys/time.h> #endif #ifdef HAVE_SYS_IOCCOM_H #include <sys/ioccom.h> #endif #ifndef WIN32 #include <sys/resource.h> #include <sys/socket.h> #include <sys/stat.h> #include <sys/wait.h> #endif #include <sys/queue.h> #ifndef WIN32 #include <netinet/in.h> #include <netdb.h> #endif #ifdef WIN32 #include <winsock2.h> #endif #include <assert.h> #include <ctype.h> #include <errno.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #ifndef WIN32 #include <syslog.h> #endif #include <signal.h> #include <time.h> #ifdef HAVE_UNISTD_H #include <unistd.h> #endif #ifdef HAVE_FCNTL_H #include <fcntl.h> #endif #undef timeout_pending #undef timeout_initialized #include "strlcpy-internal.h" #include "event.h" #include "evhttp.h" #include "evutil.h" #include "log.h" #include "http-internal.h" #ifdef WIN32 #define strcasecmp _stricmp #define strncasecmp _strnicmp #define strdup _strdup #endif #ifndef HAVE_GETNAMEINFO #define NI_MAXSERV 32 #define NI_MAXHOST 1025 #define NI_NUMERICHOST 1 #define NI_NUMERICSERV 2 static int fake_getnameinfo(const struct sockaddr *sa, size_t salen, char *host, size_t hostlen, char *serv, size_t servlen, int flags) { struct sockaddr_in *sin = (struct sockaddr_in *)sa; if (serv != NULL) { char tmpserv[16]; evutil_snprintf(tmpserv, sizeof(tmpserv), "%d", ntohs(sin->sin_port)); if (strlcpy(serv, tmpserv, servlen) >= servlen) return (-1); } if (host != NULL) { if (flags & NI_NUMERICHOST) { if (strlcpy(host, inet_ntoa(sin->sin_addr), hostlen) >= hostlen) return (-1); else return (0); } else { struct hostent *hp; hp = gethostbyaddr((char *)&sin->sin_addr, sizeof(struct in_addr), AF_INET); if (hp == NULL) return (-2); if (strlcpy(host, hp->h_name, hostlen) >= hostlen) return (-1); else return (0); } } return (0); } #endif #ifndef HAVE_GETADDRINFO struct addrinfo { int ai_family; int ai_socktype; int ai_protocol; size_t ai_addrlen; struct sockaddr *ai_addr; struct addrinfo *ai_next; }; static int fake_getaddrinfo(const char *hostname, struct addrinfo *ai) { struct hostent *he = NULL; struct sockaddr_in *sa; if (hostname) { he = gethostbyname(hostname); if (!he) return (-1); } ai->ai_family = he ? he->h_addrtype : AF_INET; ai->ai_socktype = SOCK_STREAM; ai->ai_protocol = 0; ai->ai_addrlen = sizeof(struct sockaddr_in); if (NULL == (ai->ai_addr = malloc(ai->ai_addrlen))) return (-1); sa = (struct sockaddr_in*)ai->ai_addr; memset(sa, 0, ai->ai_addrlen); if (he) { sa->sin_family = he->h_addrtype; memcpy(&sa->sin_addr, he->h_addr_list[0], he->h_length); } else { sa->sin_family = AF_INET; sa->sin_addr.s_addr = INADDR_ANY; } ai->ai_next = NULL; return (0); } static void fake_freeaddrinfo(struct addrinfo *ai) { free(ai->ai_addr); } #endif #ifndef MIN #define MIN(a,b) (((a)<(b))?(a):(b)) #endif /* wrapper for setting the base from the http server */ #define EVHTTP_BASE_SET(x, y) do { \ if ((x)->base != NULL) event_base_set((x)->base, y); \ } while (0) extern int debug; static int socket_connect(int fd, const char *address, unsigned short port); static int bind_socket_ai(struct addrinfo *, int reuse); static int bind_socket(const char *, u_short, int reuse); static void name_from_addr(struct sockaddr *, socklen_t, char **, char **); static int evhttp_associate_new_request_with_connection( struct evhttp_connection *evcon); static void evhttp_connection_start_detectclose( struct evhttp_connection *evcon); static void evhttp_connection_stop_detectclose( struct evhttp_connection *evcon); static void evhttp_request_dispatch(struct evhttp_connection* evcon); static void evhttp_read_firstline(struct evhttp_connection *evcon, struct evhttp_request *req); static void evhttp_read_header(struct evhttp_connection *evcon, struct evhttp_request *req); static int evhttp_add_header_internal(struct evkeyvalq *headers, const char *key, const char *value); static int evhttp_decode_uri_internal(const char *uri, size_t length, char *ret, int always_decode_plus); void evhttp_read(int, short, void *); void evhttp_write(int, short, void *); #ifndef HAVE_STRSEP /* strsep replacement for platforms that lack it. Only works if * del is one character long. */ static char * strsep(char **s, const char *del) { char *d, *tok; assert(strlen(del) == 1); if (!s || !*s) return NULL; tok = *s; d = strstr(tok, del); if (d) { *d = '\0'; *s = d + 1; } else *s = NULL; return tok; } #endif static const char * html_replace(char ch, char *buf) { switch (ch) { case '<': return "<"; case '>': return ">"; case '"': return """; case '\'': return "'"; case '&': return "&"; default: break; } /* Echo the character back */ buf[0] = ch; buf[1] = '\0'; return buf; } /* * Replaces <, >, ", ' and & with <, >, ", * ' and & correspondingly. * * The returned string needs to be freed by the caller. */ char * evhttp_htmlescape(const char *html) { int i, new_size = 0, old_size = strlen(html); char *escaped_html, *p; char scratch_space[2]; for (i = 0; i < old_size; ++i) new_size += strlen(html_replace(html[i], scratch_space)); p = escaped_html = malloc(new_size + 1); if (escaped_html == NULL) event_err(1, "%s: malloc(%d)", __func__, new_size + 1); for (i = 0; i < old_size; ++i) { const char *replaced = html_replace(html[i], scratch_space); /* this is length checked */ strcpy(p, replaced); p += strlen(replaced); } *p = '\0'; return (escaped_html); } static const char * evhttp_method(enum evhttp_cmd_type type) { const char *method; switch (type) { case EVHTTP_REQ_GET: method = "GET"; break; case EVHTTP_REQ_POST: method = "POST"; break; case EVHTTP_REQ_HEAD: method = "HEAD"; break; default: method = NULL; break; } return (method); } static void evhttp_add_event(struct event *ev, int timeout, int default_timeout) { if (timeout != 0) { struct timeval tv; evutil_timerclear(&tv); tv.tv_sec = timeout != -1 ? timeout : default_timeout; event_add(ev, &tv); } else { event_add(ev, NULL); } } void evhttp_write_buffer(struct evhttp_connection *evcon, void (*cb)(struct evhttp_connection *, void *), void *arg) { event_debug(("%s: preparing to write buffer\n", __func__)); /* Set call back */ evcon->cb = cb; evcon->cb_arg = arg; /* check if the event is already pending */ if (event_pending(&evcon->ev, EV_WRITE|EV_TIMEOUT, NULL)) event_del(&evcon->ev); event_set(&evcon->ev, evcon->fd, EV_WRITE, evhttp_write, evcon); EVHTTP_BASE_SET(evcon, &evcon->ev); evhttp_add_event(&evcon->ev, evcon->timeout, HTTP_WRITE_TIMEOUT); } static int evhttp_connected(struct evhttp_connection *evcon) { switch (evcon->state) { case EVCON_DISCONNECTED: case EVCON_CONNECTING: return (0); case EVCON_IDLE: case EVCON_READING_FIRSTLINE: case EVCON_READING_HEADERS: case EVCON_READING_BODY: case EVCON_READING_TRAILER: case EVCON_WRITING: default: return (1); } } /* * Create the headers needed for an HTTP request */ static void evhttp_make_header_request(struct evhttp_connection *evcon, struct evhttp_request *req) { const char *method; evhttp_remove_header(req->output_headers, "Proxy-Connection"); /* Generate request line */ method = evhttp_method(req->type); evbuffer_add_printf(evcon->output_buffer, "%s %s HTTP/%d.%d\r\n", method, req->uri, req->major, req->minor); /* Add the content length on a post request if missing */ if (req->type == EVHTTP_REQ_POST && evhttp_find_header(req->output_headers, "Content-Length") == NULL){ char size[12]; evutil_snprintf(size, sizeof(size), "%ld", (long)EVBUFFER_LENGTH(req->output_buffer)); evhttp_add_header(req->output_headers, "Content-Length", size); } } static int evhttp_is_connection_close(int flags, struct evkeyvalq* headers) { if (flags & EVHTTP_PROXY_REQUEST) { /* proxy connection */ const char *connection = evhttp_find_header(headers, "Proxy-Connection"); return (connection == NULL || strcasecmp(connection, "keep-alive") != 0); } else { const char *connection = evhttp_find_header(headers, "Connection"); return (connection != NULL && strcasecmp(connection, "close") == 0); } } static int evhttp_is_connection_keepalive(struct evkeyvalq* headers) { const char *connection = evhttp_find_header(headers, "Connection"); return (connection != NULL && strncasecmp(connection, "keep-alive", 10) == 0); } static void evhttp_maybe_add_date_header(struct evkeyvalq *headers) { if (evhttp_find_header(headers, "Date") == NULL) { char date[50]; #ifndef WIN32 struct tm cur; #endif struct tm *cur_p; time_t t = time(NULL); #ifdef WIN32 cur_p = gmtime(&t); #else gmtime_r(&t, &cur); cur_p = &cur; #endif if (strftime(date, sizeof(date), "%a, %d %b %Y %H:%M:%S GMT", cur_p) != 0) { evhttp_add_header(headers, "Date", date); } } } static void evhttp_maybe_add_content_length_header(struct evkeyvalq *headers, long content_length) { if (evhttp_find_header(headers, "Transfer-Encoding") == NULL && evhttp_find_header(headers, "Content-Length") == NULL) { char len[12]; evutil_snprintf(len, sizeof(len), "%ld", content_length); evhttp_add_header(headers, "Content-Length", len); } } /* * Create the headers needed for an HTTP reply */ static void evhttp_make_header_response(struct evhttp_connection *evcon, struct evhttp_request *req) { int is_keepalive = evhttp_is_connection_keepalive(req->input_headers); evbuffer_add_printf(evcon->output_buffer, "HTTP/%d.%d %d %s\r\n", req->major, req->minor, req->response_code, req->response_code_line); if (req->major == 1) { if (req->minor == 1) evhttp_maybe_add_date_header(req->output_headers); /* * if the protocol is 1.0; and the connection was keep-alive * we need to add a keep-alive header, too. */ if (req->minor == 0 && is_keepalive) evhttp_add_header(req->output_headers, "Connection", "keep-alive"); if (req->minor == 1 || is_keepalive) { /* * we need to add the content length if the * user did not give it, this is required for * persistent connections to work. */ evhttp_maybe_add_content_length_header( req->output_headers, (long)EVBUFFER_LENGTH(req->output_buffer)); } } /* Potentially add headers for unidentified content. */ if (EVBUFFER_LENGTH(req->output_buffer)) { if (evhttp_find_header(req->output_headers, "Content-Type") == NULL) { evhttp_add_header(req->output_headers, "Content-Type", "text/html; charset=ISO-8859-1"); } } /* if the request asked for a close, we send a close, too */ if (evhttp_is_connection_close(req->flags, req->input_headers)) { evhttp_remove_header(req->output_headers, "Connection"); if (!(req->flags & EVHTTP_PROXY_REQUEST)) evhttp_add_header(req->output_headers, "Connection", "close"); evhttp_remove_header(req->output_headers, "Proxy-Connection"); } } void evhttp_make_header(struct evhttp_connection *evcon, struct evhttp_request *req) { struct evkeyval *header; /* * Depending if this is a HTTP request or response, we might need to * add some new headers or remove existing headers. */ if (req->kind == EVHTTP_REQUEST) { evhttp_make_header_request(evcon, req); } else { evhttp_make_header_response(evcon, req); } TAILQ_FOREACH(header, req->output_headers, next) { evbuffer_add_printf(evcon->output_buffer, "%s: %s\r\n", header->key, header->value); } evbuffer_add(evcon->output_buffer, "\r\n", 2); if (EVBUFFER_LENGTH(req->output_buffer) > 0) { /* * For a request, we add the POST data, for a reply, this * is the regular data. */ evbuffer_add_buffer(evcon->output_buffer, req->output_buffer); } } /* Separated host, port and file from URI */ int evhttp_hostportfile(char *url, char **phost, u_short *pport, char **pfile) { /* XXX not threadsafe. */ static char host[1024]; static char file[1024]; char *p; const char *p2; int len; u_short port; len = strlen(HTTP_PREFIX); if (strncasecmp(url, HTTP_PREFIX, len)) return (-1); url += len; /* We might overrun */ if (strlcpy(host, url, sizeof (host)) >= sizeof(host)) return (-1); p = strchr(host, '/'); if (p != NULL) { *p = '\0'; p2 = p + 1; } else p2 = NULL; if (pfile != NULL) { /* Generate request file */ if (p2 == NULL) p2 = ""; evutil_snprintf(file, sizeof(file), "/%s", p2); } p = strchr(host, ':'); if (p != NULL) { *p = '\0'; port = atoi(p + 1); if (port == 0) return (-1); } else port = HTTP_DEFAULTPORT; if (phost != NULL) *phost = host; if (pport != NULL) *pport = port; if (pfile != NULL) *pfile = file; return (0); } static int evhttp_connection_incoming_fail(struct evhttp_request *req, enum evhttp_connection_error error) { switch (error) { case EVCON_HTTP_TIMEOUT: case EVCON_HTTP_EOF: /* * these are cases in which we probably should just * close the connection and not send a reply. this * case may happen when a browser keeps a persistent * connection open and we timeout on the read. */ return (-1); case EVCON_HTTP_INVALID_HEADER: default: /* xxx: probably should just error on default */ /* the callback looks at the uri to determine errors */ if (req->uri) { free(req->uri); req->uri = NULL; } /* * the callback needs to send a reply, once the reply has * been send, the connection should get freed. */ (*req->cb)(req, req->cb_arg); } return (0); } void evhttp_connection_fail(struct evhttp_connection *evcon, enum evhttp_connection_error error) { struct evhttp_request* req = TAILQ_FIRST(&evcon->requests); void (*cb)(struct evhttp_request *, void *); void *cb_arg; assert(req != NULL); if (evcon->flags & EVHTTP_CON_INCOMING) { /* * for incoming requests, there are two different * failure cases. it's either a network level error * or an http layer error. for problems on the network * layer like timeouts we just drop the connections. * For HTTP problems, we might have to send back a * reply before the connection can be freed. */ if (evhttp_connection_incoming_fail(req, error) == -1) evhttp_connection_free(evcon); return; } /* save the callback for later; the cb might free our object */ cb = req->cb; cb_arg = req->cb_arg; TAILQ_REMOVE(&evcon->requests, req, next); evhttp_request_free(req); /* xxx: maybe we should fail all requests??? */ /* reset the connection */ evhttp_connection_reset(evcon); /* We are trying the next request that was queued on us */ if (TAILQ_FIRST(&evcon->requests) != NULL) evhttp_connection_connect(evcon); /* inform the user */ if (cb != NULL) (*cb)(NULL, cb_arg); } void evhttp_write(int fd, short what, void *arg) { struct evhttp_connection *evcon = arg; int n; if (what == EV_TIMEOUT) { evhttp_connection_fail(evcon, EVCON_HTTP_TIMEOUT); return; } n = evbuffer_write(evcon->output_buffer, fd); if (n == -1) { event_debug(("%s: evbuffer_write", __func__)); evhttp_connection_fail(evcon, EVCON_HTTP_EOF); return; } if (n == 0) { event_debug(("%s: write nothing", __func__)); evhttp_connection_fail(evcon, EVCON_HTTP_EOF); return; } if (EVBUFFER_LENGTH(evcon->output_buffer) != 0) { evhttp_add_event(&evcon->ev, evcon->timeout, HTTP_WRITE_TIMEOUT); return; } /* Activate our call back */ if (evcon->cb != NULL) (*evcon->cb)(evcon, evcon->cb_arg); } /** * Advance the connection state. * - If this is an outgoing connection, we've just processed the response; * idle or close the connection. * - If this is an incoming connection, we've just processed the request; * respond. */ static void evhttp_connection_done(struct evhttp_connection *evcon) { struct evhttp_request *req = TAILQ_FIRST(&evcon->requests); int con_outgoing = evcon->flags & EVHTTP_CON_OUTGOING; if (con_outgoing) { /* idle or close the connection */ int need_close; TAILQ_REMOVE(&evcon->requests, req, next); req->evcon = NULL; evcon->state = EVCON_IDLE; need_close = evhttp_is_connection_close(req->flags, req->input_headers)|| evhttp_is_connection_close(req->flags, req->output_headers); /* check if we got asked to close the connection */ if (need_close) evhttp_connection_reset(evcon); if (TAILQ_FIRST(&evcon->requests) != NULL) { /* * We have more requests; reset the connection * and deal with the next request. */ if (!evhttp_connected(evcon)) evhttp_connection_connect(evcon); else evhttp_request_dispatch(evcon); } else if (!need_close) { /* * The connection is going to be persistent, but we * need to detect if the other side closes it. */ evhttp_connection_start_detectclose(evcon); } } else { /* * incoming connection - we need to leave the request on the * connection so that we can reply to it. */ evcon->state = EVCON_WRITING; } /* notify the user of the request */ (*req->cb)(req, req->cb_arg); /* if this was an outgoing request, we own and it's done. so free it */ if (con_outgoing) { evhttp_request_free(req); } } /* * Handles reading from a chunked request. * return ALL_DATA_READ: * all data has been read * return MORE_DATA_EXPECTED: * more data is expected * return DATA_CORRUPTED: * data is corrupted * return REQUEST_CANCLED: * request was canceled by the user calling evhttp_cancel_request */ static enum message_read_status evhttp_handle_chunked_read(struct evhttp_request *req, struct evbuffer *buf) { int len; while ((len = EVBUFFER_LENGTH(buf)) > 0) { if (req->ntoread < 0) { /* Read chunk size */ ev_int64_t ntoread; char *p = evbuffer_readline(buf); char *endp; int error; if (p == NULL) break; /* the last chunk is on a new line? */ if (strlen(p) == 0) { free(p); continue; } ntoread = evutil_strtoll(p, &endp, 16); error = (*p == '\0' || (*endp != '\0' && *endp != ' ') || ntoread < 0); free(p); if (error) { /* could not get chunk size */ return (DATA_CORRUPTED); } req->ntoread = ntoread; if (req->ntoread == 0) { /* Last chunk */ return (ALL_DATA_READ); } continue; } /* don't have enough to complete a chunk; wait for more */ if (len < req->ntoread) return (MORE_DATA_EXPECTED); /* Completed chunk */ evbuffer_add(req->input_buffer, EVBUFFER_DATA(buf), (size_t)req->ntoread); evbuffer_drain(buf, (size_t)req->ntoread); req->ntoread = -1; if (req->chunk_cb != NULL) { (*req->chunk_cb)(req, req->cb_arg); evbuffer_drain(req->input_buffer, EVBUFFER_LENGTH(req->input_buffer)); } } return (MORE_DATA_EXPECTED); } static void evhttp_read_trailer(struct evhttp_connection *evcon, struct evhttp_request *req) { struct evbuffer *buf = evcon->input_buffer; switch (evhttp_parse_headers(req, buf)) { case DATA_CORRUPTED: evhttp_connection_fail(evcon, EVCON_HTTP_INVALID_HEADER); break; case ALL_DATA_READ: event_del(&evcon->ev); evhttp_connection_done(evcon); break; case MORE_DATA_EXPECTED: default: evhttp_add_event(&evcon->ev, evcon->timeout, HTTP_READ_TIMEOUT); break; } } static void evhttp_read_body(struct evhttp_connection *evcon, struct evhttp_request *req) { struct evbuffer *buf = evcon->input_buffer; if (req->chunked) { switch (evhttp_handle_chunked_read(req, buf)) { case ALL_DATA_READ: /* finished last chunk */ evcon->state = EVCON_READING_TRAILER; evhttp_read_trailer(evcon, req); return; case DATA_CORRUPTED: /* corrupted data */ evhttp_connection_fail(evcon, EVCON_HTTP_INVALID_HEADER); return; case REQUEST_CANCELED: /* request canceled */ evhttp_request_free(req); return; case MORE_DATA_EXPECTED: default: break; } } else if (req->ntoread < 0) { /* Read until connection close. */ evbuffer_add_buffer(req->input_buffer, buf); } else if (EVBUFFER_LENGTH(buf) >= req->ntoread) { /* Completed content length */ evbuffer_add(req->input_buffer, EVBUFFER_DATA(buf), (size_t)req->ntoread); evbuffer_drain(buf, (size_t)req->ntoread); req->ntoread = 0; evhttp_connection_done(evcon); return; } /* Read more! */ event_set(&evcon->ev, evcon->fd, EV_READ, evhttp_read, evcon); EVHTTP_BASE_SET(evcon, &evcon->ev); evhttp_add_event(&evcon->ev, evcon->timeout, HTTP_READ_TIMEOUT); } /* * Reads data into a buffer structure until no more data * can be read on the file descriptor or we have read all * the data that we wanted to read. * Execute callback when done. */ void evhttp_read(int fd, short what, void *arg) { struct evhttp_connection *evcon = arg; struct evhttp_request *req = TAILQ_FIRST(&evcon->requests); struct evbuffer *buf = evcon->input_buffer; int n, len; if (what == EV_TIMEOUT) { evhttp_connection_fail(evcon, EVCON_HTTP_TIMEOUT); return; } n = evbuffer_read(buf, fd, -1); len = EVBUFFER_LENGTH(buf); event_debug(("%s: got %d on %d\n", __func__, n, fd)); if (n == -1) { if (errno != EINTR && errno != EAGAIN) { event_debug(("%s: evbuffer_read", __func__)); evhttp_connection_fail(evcon, EVCON_HTTP_EOF); } else { evhttp_add_event(&evcon->ev, evcon->timeout, HTTP_READ_TIMEOUT); } return; } else if (n == 0) { /* Connection closed */ evhttp_connection_done(evcon); return; } switch (evcon->state) { case EVCON_READING_FIRSTLINE: evhttp_read_firstline(evcon, req); break; case EVCON_READING_HEADERS: evhttp_read_header(evcon, req); break; case EVCON_READING_BODY: evhttp_read_body(evcon, req); break; case EVCON_READING_TRAILER: evhttp_read_trailer(evcon, req); break; case EVCON_DISCONNECTED: case EVCON_CONNECTING: case EVCON_IDLE: case EVCON_WRITING: default: event_errx(1, "%s: illegal connection state %d", __func__, evcon->state); } } static void evhttp_write_connectioncb(struct evhttp_connection *evcon, void *arg) { /* This is after writing the request to the server */ struct evhttp_request *req = TAILQ_FIRST(&evcon->requests); assert(req != NULL); assert(evcon->state == EVCON_WRITING); /* We are done writing our header and are now expecting the response */ req->kind = EVHTTP_RESPONSE; evhttp_start_read(evcon); } /* * Clean up a connection object */ void evhttp_connection_free(struct evhttp_connection *evcon) { struct evhttp_request *req; /* notify interested parties that this connection is going down */ if (evcon->fd != -1) { if (evhttp_connected(evcon) && evcon->closecb != NULL) (*evcon->closecb)(evcon, evcon->closecb_arg); } /* remove all requests that might be queued on this connection */ while ((req = TAILQ_FIRST(&evcon->requests)) != NULL) { TAILQ_REMOVE(&evcon->requests, req, next); evhttp_request_free(req); } if (evcon->http_server != NULL) { struct evhttp *http = evcon->http_server; TAILQ_REMOVE(&http->connections, evcon, next); } if (event_initialized(&evcon->close_ev)) event_del(&evcon->close_ev); if (event_initialized(&evcon->ev)) event_del(&evcon->ev); if (evcon->fd != -1) EVUTIL_CLOSESOCKET(evcon->fd); if (evcon->bind_address != NULL) free(evcon->bind_address); if (evcon->address != NULL) free(evcon->address); if (evcon->input_buffer != NULL) evbuffer_free(evcon->input_buffer); if (evcon->output_buffer != NULL) evbuffer_free(evcon->output_buffer); free(evcon); } void evhttp_connection_set_local_address(struct evhttp_connection *evcon, const char *address) { assert(evcon->state == EVCON_DISCONNECTED); if (evcon->bind_address) free(evcon->bind_address); if ((evcon->bind_address = strdup(address)) == NULL) event_err(1, "%s: strdup", __func__); } void evhttp_connection_set_local_port(struct evhttp_connection *evcon, unsigned short port) { assert(evcon->state == EVCON_DISCONNECTED); evcon->bind_port = port; } static void evhttp_request_dispatch(struct evhttp_connection* evcon) { struct evhttp_request *req = TAILQ_FIRST(&evcon->requests); /* this should not usually happy but it's possible */ if (req == NULL) return; /* delete possible close detection events */ evhttp_connection_stop_detectclose(evcon); /* we assume that the connection is connected already */ assert(evcon->state == EVCON_IDLE); evcon->state = EVCON_WRITING; /* Create the header from the store arguments */ evhttp_make_header(evcon, req); evhttp_write_buffer(evcon, evhttp_write_connectioncb, NULL); } /* Reset our connection state */ void evhttp_connection_reset(struct evhttp_connection *evcon) { if (event_initialized(&evcon->ev)) event_del(&evcon->ev); if (evcon->fd != -1) { /* inform interested parties about connection close */ if (evhttp_connected(evcon) && evcon->closecb != NULL) (*evcon->closecb)(evcon, evcon->closecb_arg); EVUTIL_CLOSESOCKET(evcon->fd); evcon->fd = -1; } evcon->state = EVCON_DISCONNECTED; evbuffer_drain(evcon->input_buffer, EVBUFFER_LENGTH(evcon->input_buffer)); evbuffer_drain(evcon->output_buffer, EVBUFFER_LENGTH(evcon->output_buffer)); } static void evhttp_detect_close_cb(int fd, short what, void *arg) { struct evhttp_connection *evcon = arg; evhttp_connection_reset(evcon); } static void evhttp_connection_start_detectclose(struct evhttp_connection *evcon) { evcon->flags |= EVHTTP_CON_CLOSEDETECT; if (event_initialized(&evcon->close_ev)) event_del(&evcon->close_ev); event_set(&evcon->close_ev, evcon->fd, EV_READ, evhttp_detect_close_cb, evcon); EVHTTP_BASE_SET(evcon, &evcon->close_ev); event_add(&evcon->close_ev, NULL); } static void evhttp_connection_stop_detectclose(struct evhttp_connection *evcon) { evcon->flags &= ~EVHTTP_CON_CLOSEDETECT; event_del(&evcon->close_ev); } static void evhttp_connection_retry(int fd, short what, void *arg) { struct evhttp_connection *evcon = arg; evcon->state = EVCON_DISCONNECTED; evhttp_connection_connect(evcon); } /* * Call back for asynchronous connection attempt. */ static void evhttp_connectioncb(int fd, short what, void *arg) { struct evhttp_connection *evcon = arg; int error; socklen_t errsz = sizeof(error); if (what == EV_TIMEOUT) { event_debug(("%s: connection timeout for \"%s:%d\" on %d", __func__, evcon->address, evcon->port, evcon->fd)); goto cleanup; } /* Check if the connection completed */ if (getsockopt(evcon->fd, SOL_SOCKET, SO_ERROR, (void*)&error, &errsz) == -1) { event_debug(("%s: getsockopt for \"%s:%d\" on %d", __func__, evcon->address, evcon->port, evcon->fd)); goto cleanup; } if (error) { event_debug(("%s: connect failed for \"%s:%d\" on %d: %s", __func__, evcon->address, evcon->port, evcon->fd, strerror(error))); goto cleanup; } /* We are connected to the server now */ event_debug(("%s: connected to \"%s:%d\" on %d\n", __func__, evcon->address, evcon->port, evcon->fd)); /* Reset the retry count as we were successful in connecting */ evcon->retry_cnt = 0; evcon->state = EVCON_IDLE; /* try to start requests that have queued up on this connection */ evhttp_request_dispatch(evcon); return; cleanup: if (evcon->retry_max < 0 || evcon->retry_cnt < evcon->retry_max) { evtimer_set(&evcon->ev, evhttp_connection_retry, evcon); EVHTTP_BASE_SET(evcon, &evcon->ev); evhttp_add_event(&evcon->ev, MIN(3600, 2 << evcon->retry_cnt), HTTP_CONNECT_TIMEOUT); evcon->retry_cnt++; return; } evhttp_connection_reset(evcon); /* for now, we just signal all requests by executing their callbacks */ while (TAILQ_FIRST(&evcon->requests) != NULL) { struct evhttp_request *request = TAILQ_FIRST(&evcon->requests); TAILQ_REMOVE(&evcon->requests, request, next); request->evcon = NULL; /* we might want to set an error here */ request->cb(request, request->cb_arg); evhttp_request_free(request); } } /* * Check if we got a valid response code. */ static int evhttp_valid_response_code(int code) { if (code == 0) return (0); return (1); } /* Parses the status line of a web server */ static int evhttp_parse_response_line(struct evhttp_request *req, char *line) { char *protocol; char *number; char *readable; protocol = strsep(&line, " "); if (line == NULL) return (-1); number = strsep(&line, " "); if (line == NULL) return (-1); readable = line; if (strcmp(protocol, "HTTP/1.0") == 0) { req->major = 1; req->minor = 0; } else if (strcmp(protocol, "HTTP/1.1") == 0) { req->major = 1; req->minor = 1; } else { event_debug(("%s: bad protocol \"%s\"", __func__, protocol)); return (-1); } req->response_code = atoi(number); if (!evhttp_valid_response_code(req->response_code)) { event_debug(("%s: bad response code \"%s\"", __func__, number)); return (-1); } if ((req->response_code_line = strdup(readable)) == NULL) event_err(1, "%s: strdup", __func__); return (0); } /* Parse the first line of a HTTP request */ static int evhttp_parse_request_line(struct evhttp_request *req, char *line) { char *method; char *uri; char *version; /* Parse the request line */ method = strsep(&line, " "); if (line == NULL) return (-1); uri = strsep(&line, " "); if (line == NULL) return (-1); version = strsep(&line, " "); if (line != NULL) return (-1); /* First line */ if (strcmp(method, "GET") == 0) { req->type = EVHTTP_REQ_GET; } else if (strcmp(method, "POST") == 0) { req->type = EVHTTP_REQ_POST; } else if (strcmp(method, "HEAD") == 0) { req->type = EVHTTP_REQ_HEAD; } else { event_debug(("%s: bad method %s on request %p from %s", __func__, method, req, req->remote_host)); return (-1); } if (strcmp(version, "HTTP/1.0") == 0) { req->major = 1; req->minor = 0; } else if (strcmp(version, "HTTP/1.1") == 0) { req->major = 1; req->minor = 1; } else { event_debug(("%s: bad version %s on request %p from %s", __func__, version, req, req->remote_host)); return (-1); } if ((req->uri = strdup(uri)) == NULL) { event_debug(("%s: evhttp_decode_uri", __func__)); return (-1); } /* determine if it's a proxy request */ if (strlen(req->uri) > 0 && req->uri[0] != '/') req->flags |= EVHTTP_PROXY_REQUEST; return (0); } const char * evhttp_find_header(const struct evkeyvalq *headers, const char *key) { struct evkeyval *header; TAILQ_FOREACH(header, headers, next) { if (strcasecmp(header->key, key) == 0) return (header->value); } return (NULL); } void evhttp_clear_headers(struct evkeyvalq *headers) { struct evkeyval *header; for (header = TAILQ_FIRST(headers); header != NULL; header = TAILQ_FIRST(headers)) { TAILQ_REMOVE(headers, header, next); free(header->key); free(header->value); free(header); } } /* * Returns 0, if the header was successfully removed. * Returns -1, if the header could not be found. */ int evhttp_remove_header(struct evkeyvalq *headers, const char *key) { struct evkeyval *header; TAILQ_FOREACH(header, headers, next) { if (strcasecmp(header->key, key) == 0) break; } if (header == NULL) return (-1); /* Free and remove the header that we found */ TAILQ_REMOVE(headers, header, next); free(header->key); free(header->value); free(header); return (0); } static int evhttp_header_is_valid_value(const char *value) { const char *p = value; while ((p = strpbrk(p, "\r\n")) != NULL) { /* we really expect only one new line */ p += strspn(p, "\r\n"); /* we expect a space or tab for continuation */ if (*p != ' ' && *p != '\t') return (0); } return (1); } int evhttp_add_header(struct evkeyvalq *headers, const char *key, const char *value) { event_debug(("%s: key: %s val: %s\n", __func__, key, value)); if (strchr(key, '\r') != NULL || strchr(key, '\n') != NULL) { /* drop illegal headers */ event_debug(("%s: dropping illegal header key\n", __func__)); return (-1); } if (!evhttp_header_is_valid_value(value)) { event_debug(("%s: dropping illegal header value\n", __func__)); return (-1); } return (evhttp_add_header_internal(headers, key, value)); } static int evhttp_add_header_internal(struct evkeyvalq *headers, const char *key, const char *value) { struct evkeyval *header = calloc(1, sizeof(struct evkeyval)); if (header == NULL) { event_warn("%s: calloc", __func__); return (-1); } if ((header->key = strdup(key)) == NULL) { free(header); event_warn("%s: strdup", __func__); return (-1); } if ((header->value = strdup(value)) == NULL) { free(header->key); free(header); event_warn("%s: strdup", __func__); return (-1); } TAILQ_INSERT_TAIL(headers, header, next); return (0); } /* * Parses header lines from a request or a response into the specified * request object given an event buffer. * * Returns * DATA_CORRUPTED on error * MORE_DATA_EXPECTED when we need to read more headers * ALL_DATA_READ when all headers have been read. */ enum message_read_status evhttp_parse_firstline(struct evhttp_request *req, struct evbuffer *buffer) { char *line; enum message_read_status status = ALL_DATA_READ; line = evbuffer_readline(buffer); if (line == NULL) return (MORE_DATA_EXPECTED); switch (req->kind) { case EVHTTP_REQUEST: if (evhttp_parse_request_line(req, line) == -1) status = DATA_CORRUPTED; break; case EVHTTP_RESPONSE: if (evhttp_parse_response_line(req, line) == -1) status = DATA_CORRUPTED; break; default: status = DATA_CORRUPTED; } free(line); return (status); } static int evhttp_append_to_last_header(struct evkeyvalq *headers, const char *line) { struct evkeyval *header = TAILQ_LAST(headers, evkeyvalq); char *newval; size_t old_len, line_len; if (header == NULL) return (-1); old_len = strlen(header->value); line_len = strlen(line); newval = realloc(header->value, old_len + line_len + 1); if (newval == NULL) return (-1); memcpy(newval + old_len, line, line_len + 1); header->value = newval; return (0); } enum message_read_status evhttp_parse_headers(struct evhttp_request *req, struct evbuffer* buffer) { char *line; enum message_read_status status = MORE_DATA_EXPECTED; struct evkeyvalq* headers = req->input_headers; while ((line = evbuffer_readline(buffer)) != NULL) { char *skey, *svalue; if (*line == '\0') { /* Last header - Done */ status = ALL_DATA_READ; free(line); break; } /* Check if this is a continuation line */ if (*line == ' ' || *line == '\t') { if (evhttp_append_to_last_header(headers, line) == -1) goto error; free(line); continue; } /* Processing of header lines */ svalue = line; skey = strsep(&svalue, ":"); if (svalue == NULL) goto error; svalue += strspn(svalue, " "); if (evhttp_add_header(headers, skey, svalue) == -1) goto error; free(line); } return (status); error: free(line); return (DATA_CORRUPTED); } static int evhttp_get_body_length(struct evhttp_request *req) { struct evkeyvalq *headers = req->input_headers; const char *content_length; const char *connection; content_length = evhttp_find_header(headers, "Content-Length"); connection = evhttp_find_header(headers, "Connection"); if (content_length == NULL && connection == NULL) req->ntoread = -1; else if (content_length == NULL && strcasecmp(connection, "Close") != 0) { /* Bad combination, we don't know when it will end */ event_warnx("%s: we got no content length, but the " "server wants to keep the connection open: %s.", __func__, connection); return (-1); } else if (content_length == NULL) { req->ntoread = -1; } else { char *endp; ev_int64_t ntoread = evutil_strtoll(content_length, &endp, 10); if (*content_length == '\0' || *endp != '\0' || ntoread < 0) { event_debug(("%s: illegal content length: %s", __func__, content_length)); return (-1); } req->ntoread = ntoread; } event_debug(("%s: bytes to read: %lld (in buffer %ld)\n", __func__, req->ntoread, EVBUFFER_LENGTH(req->evcon->input_buffer))); return (0); } static void evhttp_get_body(struct evhttp_connection *evcon, struct evhttp_request *req) { const char *xfer_enc; /* If this is a request without a body, then we are done */ if (req->kind == EVHTTP_REQUEST && req->type != EVHTTP_REQ_POST) { evhttp_connection_done(evcon); return; } evcon->state = EVCON_READING_BODY; xfer_enc = evhttp_find_header(req->input_headers, "Transfer-Encoding"); if (xfer_enc != NULL && strcasecmp(xfer_enc, "chunked") == 0) { req->chunked = 1; req->ntoread = -1; } else { if (evhttp_get_body_length(req) == -1) { evhttp_connection_fail(evcon, EVCON_HTTP_INVALID_HEADER); return; } } evhttp_read_body(evcon, req); } static void evhttp_read_firstline(struct evhttp_connection *evcon, struct evhttp_request *req) { enum message_read_status res; res = evhttp_parse_firstline(req, evcon->input_buffer); if (res == DATA_CORRUPTED) { /* Error while reading, terminate */ event_debug(("%s: bad header lines on %d\n", __func__, evcon->fd)); evhttp_connection_fail(evcon, EVCON_HTTP_INVALID_HEADER); return; } else if (res == MORE_DATA_EXPECTED) { /* Need more header lines */ evhttp_add_event(&evcon->ev, evcon->timeout, HTTP_READ_TIMEOUT); return; } evcon->state = EVCON_READING_HEADERS; evhttp_read_header(evcon, req); } static void evhttp_read_header(struct evhttp_connection *evcon, struct evhttp_request *req) { enum message_read_status res; int fd = evcon->fd; res = evhttp_parse_headers(req, evcon->input_buffer); if (res == DATA_CORRUPTED) { /* Error while reading, terminate */ event_debug(("%s: bad header lines on %d\n", __func__, fd)); evhttp_connection_fail(evcon, EVCON_HTTP_INVALID_HEADER); return; } else if (res == MORE_DATA_EXPECTED) { /* Need more header lines */ evhttp_add_event(&evcon->ev, evcon->timeout, HTTP_READ_TIMEOUT); return; } /* Done reading headers, do the real work */ switch (req->kind) { case EVHTTP_REQUEST: event_debug(("%s: checking for post data on %d\n", __func__, fd)); evhttp_get_body(evcon, req); break; case EVHTTP_RESPONSE: if (req->response_code == HTTP_NOCONTENT || req->response_code == HTTP_NOTMODIFIED || (req->response_code >= 100 && req->response_code < 200)) { event_debug(("%s: skipping body for code %d\n", __func__, req->response_code)); evhttp_connection_done(evcon); } else { event_debug(("%s: start of read body for %s on %d\n", __func__, req->remote_host, fd)); evhttp_get_body(evcon, req); } break; default: event_warnx("%s: bad header on %d", __func__, fd); evhttp_connection_fail(evcon, EVCON_HTTP_INVALID_HEADER); break; } } /* * Creates a TCP connection to the specified port and executes a callback * when finished. Failure or sucess is indicate by the passed connection * object. * * Although this interface accepts a hostname, it is intended to take * only numeric hostnames so that non-blocking DNS resolution can * happen elsewhere. */ struct evhttp_connection * evhttp_connection_new(const char *address, unsigned short port) { struct evhttp_connection *evcon = NULL; event_debug(("Attempting connection to %s:%d\n", address, port)); if ((evcon = calloc(1, sizeof(struct evhttp_connection))) == NULL) { event_warn("%s: calloc failed", __func__); goto error; } evcon->fd = -1; evcon->port = port; evcon->timeout = -1; evcon->retry_cnt = evcon->retry_max = 0; if ((evcon->address = strdup(address)) == NULL) { event_warn("%s: strdup failed", __func__); goto error; } if ((evcon->input_buffer = evbuffer_new()) == NULL) { event_warn("%s: evbuffer_new failed", __func__); goto error; } if ((evcon->output_buffer = evbuffer_new()) == NULL) { event_warn("%s: evbuffer_new failed", __func__); goto error; } evcon->state = EVCON_DISCONNECTED; TAILQ_INIT(&evcon->requests); return (evcon); error: if (evcon != NULL) evhttp_connection_free(evcon); return (NULL); } void evhttp_connection_set_base(struct evhttp_connection *evcon, struct event_base *base) { assert(evcon->base == NULL); assert(evcon->state == EVCON_DISCONNECTED); evcon->base = base; } void evhttp_connection_set_timeout(struct evhttp_connection *evcon, int timeout_in_secs) { evcon->timeout = timeout_in_secs; } void evhttp_connection_set_retries(struct evhttp_connection *evcon, int retry_max) { evcon->retry_max = retry_max; } void evhttp_connection_set_closecb(struct evhttp_connection *evcon, void (*cb)(struct evhttp_connection *, void *), void *cbarg) { evcon->closecb = cb; evcon->closecb_arg = cbarg; } void evhttp_connection_get_peer(struct evhttp_connection *evcon, char **address, u_short *port) { *address = evcon->address; *port = evcon->port; } int evhttp_connection_connect(struct evhttp_connection *evcon) { if (evcon->state == EVCON_CONNECTING) return (0); evhttp_connection_reset(evcon); assert(!(evcon->flags & EVHTTP_CON_INCOMING)); evcon->flags |= EVHTTP_CON_OUTGOING; evcon->fd = bind_socket( evcon->bind_address, evcon->bind_port, 0 /*reuse*/); if (evcon->fd == -1) { event_debug(("%s: failed to bind to \"%s\"", __func__, evcon->bind_address)); return (-1); } if (socket_connect(evcon->fd, evcon->address, evcon->port) == -1) { EVUTIL_CLOSESOCKET(evcon->fd); evcon->fd = -1; return (-1); } /* Set up a callback for successful connection setup */ event_set(&evcon->ev, evcon->fd, EV_WRITE, evhttp_connectioncb, evcon); EVHTTP_BASE_SET(evcon, &evcon->ev); evhttp_add_event(&evcon->ev, evcon->timeout, HTTP_CONNECT_TIMEOUT); evcon->state = EVCON_CONNECTING; return (0); } /* * Starts an HTTP request on the provided evhttp_connection object. * If the connection object is not connected to the web server already, * this will start the connection. */ int evhttp_make_request(struct evhttp_connection *evcon, struct evhttp_request *req, enum evhttp_cmd_type type, const char *uri) { /* We are making a request */ req->kind = EVHTTP_REQUEST; req->type = type; if (req->uri != NULL) free(req->uri); if ((req->uri = strdup(uri)) == NULL) event_err(1, "%s: strdup", __func__); /* Set the protocol version if it is not supplied */ if (!req->major && !req->minor) { req->major = 1; req->minor = 1; } assert(req->evcon == NULL); req->evcon = evcon; assert(!(req->flags & EVHTTP_REQ_OWN_CONNECTION)); TAILQ_INSERT_TAIL(&evcon->requests, req, next); /* If the connection object is not connected; make it so */ if (!evhttp_connected(evcon)) return (evhttp_connection_connect(evcon)); /* * If it's connected already and we are the first in the queue, * then we can dispatch this request immediately. Otherwise, it * will be dispatched once the pending requests are completed. */ if (TAILQ_FIRST(&evcon->requests) == req) evhttp_request_dispatch(evcon); return (0); } /* * Reads data from file descriptor into request structure * Request structure needs to be set up correctly. */ void evhttp_start_read(struct evhttp_connection *evcon) { /* Set up an event to read the headers */ if (event_initialized(&evcon->ev)) event_del(&evcon->ev); event_set(&evcon->ev, evcon->fd, EV_READ, evhttp_read, evcon); EVHTTP_BASE_SET(evcon, &evcon->ev); evhttp_add_event(&evcon->ev, evcon->timeout, HTTP_READ_TIMEOUT); evcon->state = EVCON_READING_FIRSTLINE; } static void evhttp_send_done(struct evhttp_connection *evcon, void *arg) { int need_close; struct evhttp_request *req = TAILQ_FIRST(&evcon->requests); TAILQ_REMOVE(&evcon->requests, req, next); /* delete possible close detection events */ evhttp_connection_stop_detectclose(evcon); need_close = (req->minor == 0 && !evhttp_is_connection_keepalive(req->input_headers))|| evhttp_is_connection_close(req->flags, req->input_headers) || evhttp_is_connection_close(req->flags, req->output_headers); assert(req->flags & EVHTTP_REQ_OWN_CONNECTION); evhttp_request_free(req); if (need_close) { evhttp_connection_free(evcon); return; } /* we have a persistent connection; try to accept another request. */ if (evhttp_associate_new_request_with_connection(evcon) == -1) evhttp_connection_free(evcon); } /* * Returns an error page. */ void evhttp_send_error(struct evhttp_request *req, int error, const char *reason) { #define ERR_FORMAT "<HTML><HEAD>\n" \ "<TITLE>%d %s</TITLE>\n" \ "</HEAD><BODY>\n" \ "<H1>Method Not Implemented</H1>\n" \ "Invalid method in request<P>\n" \ "</BODY></HTML>\n" struct evbuffer *buf = evbuffer_new(); /* close the connection on error */ evhttp_add_header(req->output_headers, "Connection", "close"); evhttp_response_code(req, error, reason); evbuffer_add_printf(buf, ERR_FORMAT, error, reason); evhttp_send_page(req, buf); evbuffer_free(buf); #undef ERR_FORMAT } /* Requires that headers and response code are already set up */ static inline void evhttp_send(struct evhttp_request *req, struct evbuffer *databuf) { struct evhttp_connection *evcon = req->evcon; assert(TAILQ_FIRST(&evcon->requests) == req); /* xxx: not sure if we really should expose the data buffer this way */ if (databuf != NULL) evbuffer_add_buffer(req->output_buffer, databuf); /* Adds headers to the response */ evhttp_make_header(evcon, req); evhttp_write_buffer(evcon, evhttp_send_done, NULL); } void evhttp_send_reply(struct evhttp_request *req, int code, const char *reason, struct evbuffer *databuf) { evhttp_response_code(req, code, reason); evhttp_send(req, databuf); } void evhttp_send_reply_start(struct evhttp_request *req, int code, const char *reason) { evhttp_response_code(req, code, reason); if (req->major == 1 && req->minor == 1) { /* use chunked encoding for HTTP/1.1 */ evhttp_add_header(req->output_headers, "Transfer-Encoding", "chunked"); req->chunked = 1; } evhttp_make_header(req->evcon, req); evhttp_write_buffer(req->evcon, NULL, NULL); } void evhttp_send_reply_chunk(struct evhttp_request *req, struct evbuffer *databuf) { if (req->chunked) { evbuffer_add_printf(req->evcon->output_buffer, "%x\r\n", (unsigned)EVBUFFER_LENGTH(databuf)); } evbuffer_add_buffer(req->evcon->output_buffer, databuf); if (req->chunked) { evbuffer_add(req->evcon->output_buffer, "\r\n", 2); } evhttp_write_buffer(req->evcon, NULL, NULL); } void evhttp_send_reply_end(struct evhttp_request *req) { struct evhttp_connection *evcon = req->evcon; if (req->chunked) { evbuffer_add(req->evcon->output_buffer, "0\r\n\r\n", 5); evhttp_write_buffer(req->evcon, evhttp_send_done, NULL); req->chunked = 0; } else if (!event_pending(&evcon->ev, EV_WRITE|EV_TIMEOUT, NULL)) { /* let the connection know that we are done with the request */ evhttp_send_done(evcon, NULL); } else { /* make the callback execute after all data has been written */ evcon->cb = evhttp_send_done; evcon->cb_arg = NULL; } } void evhttp_response_code(struct evhttp_request *req, int code, const char *reason) { req->kind = EVHTTP_RESPONSE; req->response_code = code; if (req->response_code_line != NULL) free(req->response_code_line); req->response_code_line = strdup(reason); } void evhttp_send_page(struct evhttp_request *req, struct evbuffer *databuf) { if (!req->major || !req->minor) { req->major = 1; req->minor = 1; } if (req->kind != EVHTTP_RESPONSE) evhttp_response_code(req, 200, "OK"); evhttp_clear_headers(req->output_headers); evhttp_add_header(req->output_headers, "Content-Type", "text/html"); evhttp_add_header(req->output_headers, "Connection", "close"); evhttp_send(req, databuf); } static const char uri_chars[256] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 0, 0, /* 64 */ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 0, /* 128 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 192 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }; /* * Helper functions to encode/decode a URI. * The returned string must be freed by the caller. */ char * evhttp_encode_uri(const char *uri) { struct evbuffer *buf = evbuffer_new(); char *p; for (p = (char *)uri; *p != '\0'; p++) { if (uri_chars[(u_char)(*p)]) { evbuffer_add(buf, p, 1); } else { evbuffer_add_printf(buf, "%%%02X", (u_char)(*p)); } } evbuffer_add(buf, "", 1); p = strdup((char *)EVBUFFER_DATA(buf)); evbuffer_free(buf); return (p); } /* * @param always_decode_plus: when true we transform plus to space even * if we have not seen a ?. */ static int evhttp_decode_uri_internal( const char *uri, size_t length, char *ret, int always_decode_plus) { char c; int i, j, in_query = always_decode_plus; for (i = j = 0; uri[i] != '\0'; i++) { c = uri[i]; if (c == '?') { in_query = 1; } else if (c == '+' && in_query) { c = ' '; } else if (c == '%' && isxdigit((unsigned char)uri[i+1]) && isxdigit((unsigned char)uri[i+2])) { char tmp[] = { uri[i+1], uri[i+2], '\0' }; c = (char)strtol(tmp, NULL, 16); i += 2; } ret[j++] = c; } ret[j] = '\0'; return (j); } char * evhttp_decode_uri(const char *uri) { char *ret; if ((ret = malloc(strlen(uri) + 1)) == NULL) event_err(1, "%s: malloc(%lu)", __func__, (unsigned long)(strlen(uri) + 1)); evhttp_decode_uri_internal(uri, strlen(uri), ret, 0 /*always_decode_plus*/); return (ret); } /* * Helper function to parse out arguments in a query. * The arguments are separated by key and value. */ void evhttp_parse_query(const char *uri, struct evkeyvalq *headers) { char *line; char *argument; char *p; TAILQ_INIT(headers); /* No arguments - we are done */ if (strchr(uri, '?') == NULL) return; if ((line = strdup(uri)) == NULL) event_err(1, "%s: strdup", __func__); argument = line; /* We already know that there has to be a ? */ strsep(&argument, "?"); p = argument; while (p != NULL && *p != '\0') { char *key, *value, *decoded_value; argument = strsep(&p, "&"); value = argument; key = strsep(&value, "="); if (value == NULL) goto error; if ((decoded_value = malloc(strlen(value) + 1)) == NULL) event_err(1, "%s: malloc", __func__); evhttp_decode_uri_internal(value, strlen(value), decoded_value, 1 /*always_decode_plus*/); event_debug(("Query Param: %s -> %s\n", key, decoded_value)); evhttp_add_header_internal(headers, key, decoded_value); free(decoded_value); } error: free(line); } static struct evhttp_cb * evhttp_dispatch_callback(struct httpcbq *callbacks, struct evhttp_request *req) { struct evhttp_cb *cb; size_t offset = 0; /* Test for different URLs */ char *p = strchr(req->uri, '?'); if (p != NULL) offset = (size_t)(p - req->uri); TAILQ_FOREACH(cb, callbacks, next) { int res = 0; if (p == NULL) { res = strcmp(cb->what, req->uri) == 0; } else { res = ((strncmp(cb->what, req->uri, offset) == 0) && (cb->what[offset] == '\0')); } if (res) return (cb); } return (NULL); } static void evhttp_handle_request(struct evhttp_request *req, void *arg) { struct evhttp *http = arg; struct evhttp_cb *cb = NULL; if (req->uri == NULL) { evhttp_send_error(req, HTTP_BADREQUEST, "Bad Request"); return; } if ((cb = evhttp_dispatch_callback(&http->callbacks, req)) != NULL) { (*cb->cb)(req, cb->cbarg); return; } /* Generic call back */ if (http->gencb) { (*http->gencb)(req, http->gencbarg); return; } else { /* We need to send a 404 here */ #define ERR_FORMAT "<html><head>" \ "<title>404 Not Found</title>" \ "</head><body>" \ "<h1>Not Found</h1>" \ "<p>The requested URL %s was not found on this server.</p>"\ "</body></html>\n" char *escaped_html = evhttp_htmlescape(req->uri); struct evbuffer *buf = evbuffer_new(); evhttp_response_code(req, HTTP_NOTFOUND, "Not Found"); evbuffer_add_printf(buf, ERR_FORMAT, escaped_html); free(escaped_html); evhttp_send_page(req, buf); evbuffer_free(buf); #undef ERR_FORMAT } } static void accept_socket(int fd, short what, void *arg) { struct evhttp *http = arg; struct sockaddr_storage ss; socklen_t addrlen = sizeof(ss); int nfd; if ((nfd = accept(fd, (struct sockaddr *)&ss, &addrlen)) == -1) { if (errno != EAGAIN && errno != EINTR) event_warn("%s: bad accept", __func__); return; } if (evutil_make_socket_nonblocking(nfd) < 0) return; evhttp_get_request(http, nfd, (struct sockaddr *)&ss, addrlen); } int evhttp_bind_socket(struct evhttp *http, const char *address, u_short port) { int fd; int res; if ((fd = bind_socket(address, port, 1 /*reuse*/)) == -1) return (-1); if (listen(fd, 128) == -1) { event_warn("%s: listen", __func__); EVUTIL_CLOSESOCKET(fd); return (-1); } res = evhttp_accept_socket(http, fd); if (res != -1) event_debug(("Bound to port %d - Awaiting connections ... ", port)); return (res); } int evhttp_accept_socket(struct evhttp *http, int fd) { struct evhttp_bound_socket *bound; struct event *ev; int res; bound = malloc(sizeof(struct evhttp_bound_socket)); if (bound == NULL) return (-1); ev = &bound->bind_ev; /* Schedule the socket for accepting */ event_set(ev, fd, EV_READ | EV_PERSIST, accept_socket, http); EVHTTP_BASE_SET(http, ev); res = event_add(ev, NULL); if (res == -1) { free(bound); return (-1); } TAILQ_INSERT_TAIL(&http->sockets, bound, next); return (0); } static struct evhttp* evhttp_new_object(void) { struct evhttp *http = NULL; if ((http = calloc(1, sizeof(struct evhttp))) == NULL) { event_warn("%s: calloc", __func__); return (NULL); } http->timeout = -1; TAILQ_INIT(&http->sockets); TAILQ_INIT(&http->callbacks); TAILQ_INIT(&http->connections); return (http); } struct evhttp * evhttp_new(struct event_base *base) { struct evhttp *http = evhttp_new_object(); http->base = base; return (http); } /* * Start a web server on the specified address and port. */ struct evhttp * evhttp_start(const char *address, u_short port) { struct evhttp *http = evhttp_new_object(); if (evhttp_bind_socket(http, address, port) == -1) { free(http); return (NULL); } return (http); } void evhttp_free(struct evhttp* http) { struct evhttp_cb *http_cb; struct evhttp_connection *evcon; struct evhttp_bound_socket *bound; int fd; /* Remove the accepting part */ while ((bound = TAILQ_FIRST(&http->sockets)) != NULL) { TAILQ_REMOVE(&http->sockets, bound, next); fd = bound->bind_ev.ev_fd; event_del(&bound->bind_ev); EVUTIL_CLOSESOCKET(fd); free(bound); } while ((evcon = TAILQ_FIRST(&http->connections)) != NULL) { /* evhttp_connection_free removes the connection */ evhttp_connection_free(evcon); } while ((http_cb = TAILQ_FIRST(&http->callbacks)) != NULL) { TAILQ_REMOVE(&http->callbacks, http_cb, next); free(http_cb->what); free(http_cb); } free(http); } void evhttp_set_timeout(struct evhttp* http, int timeout_in_secs) { http->timeout = timeout_in_secs; } void evhttp_set_cb(struct evhttp *http, const char *uri, void (*cb)(struct evhttp_request *, void *), void *cbarg) { struct evhttp_cb *http_cb; if ((http_cb = calloc(1, sizeof(struct evhttp_cb))) == NULL) event_err(1, "%s: calloc", __func__); http_cb->what = strdup(uri); http_cb->cb = cb; http_cb->cbarg = cbarg; TAILQ_INSERT_TAIL(&http->callbacks, http_cb, next); } int evhttp_del_cb(struct evhttp *http, const char *uri) { struct evhttp_cb *http_cb; TAILQ_FOREACH(http_cb, &http->callbacks, next) { if (strcmp(http_cb->what, uri) == 0) break; } if (http_cb == NULL) return (-1); TAILQ_REMOVE(&http->callbacks, http_cb, next); free(http_cb->what); free(http_cb); return (0); } void evhttp_set_gencb(struct evhttp *http, void (*cb)(struct evhttp_request *, void *), void *cbarg) { http->gencb = cb; http->gencbarg = cbarg; } /* * Request related functions */ struct evhttp_request * evhttp_request_new(void (*cb)(struct evhttp_request *, void *), void *arg) { struct evhttp_request *req = NULL; /* Allocate request structure */ if ((req = calloc(1, sizeof(struct evhttp_request))) == NULL) { event_warn("%s: calloc", __func__); goto error; } req->kind = EVHTTP_RESPONSE; req->input_headers = calloc(1, sizeof(struct evkeyvalq)); if (req->input_headers == NULL) { event_warn("%s: calloc", __func__); goto error; } TAILQ_INIT(req->input_headers); req->output_headers = calloc(1, sizeof(struct evkeyvalq)); if (req->output_headers == NULL) { event_warn("%s: calloc", __func__); goto error; } TAILQ_INIT(req->output_headers); if ((req->input_buffer = evbuffer_new()) == NULL) { event_warn("%s: evbuffer_new", __func__); goto error; } if ((req->output_buffer = evbuffer_new()) == NULL) { event_warn("%s: evbuffer_new", __func__); goto error; } req->cb = cb; req->cb_arg = arg; return (req); error: if (req != NULL) evhttp_request_free(req); return (NULL); } void evhttp_request_free(struct evhttp_request *req) { if (req->remote_host != NULL) free(req->remote_host); if (req->uri != NULL) free(req->uri); if (req->response_code_line != NULL) free(req->response_code_line); evhttp_clear_headers(req->input_headers); free(req->input_headers); evhttp_clear_headers(req->output_headers); free(req->output_headers); if (req->input_buffer != NULL) evbuffer_free(req->input_buffer); if (req->output_buffer != NULL) evbuffer_free(req->output_buffer); free(req); } void evhttp_request_set_chunked_cb(struct evhttp_request *req, void (*cb)(struct evhttp_request *, void *)) { req->chunk_cb = cb; } /* * Allows for inspection of the request URI */ const char * evhttp_request_uri(struct evhttp_request *req) { if (req->uri == NULL) event_debug(("%s: request %p has no uri\n", __func__, req)); return (req->uri); } /* * Takes a file descriptor to read a request from. * The callback is executed once the whole request has been read. */ static struct evhttp_connection* evhttp_get_request_connection( struct evhttp* http, int fd, struct sockaddr *sa, socklen_t salen) { struct evhttp_connection *evcon; char *hostname = NULL, *portname = NULL; name_from_addr(sa, salen, &hostname, &portname); if (hostname == NULL || portname == NULL) { if (hostname) free(hostname); if (portname) free(portname); return (NULL); } event_debug(("%s: new request from %s:%s on %d\n", __func__, hostname, portname, fd)); /* we need a connection object to put the http request on */ evcon = evhttp_connection_new(hostname, atoi(portname)); free(hostname); free(portname); if (evcon == NULL) return (NULL); /* associate the base if we have one*/ evhttp_connection_set_base(evcon, http->base); evcon->flags |= EVHTTP_CON_INCOMING; evcon->state = EVCON_READING_FIRSTLINE; evcon->fd = fd; return (evcon); } static int evhttp_associate_new_request_with_connection(struct evhttp_connection *evcon) { struct evhttp *http = evcon->http_server; struct evhttp_request *req; if ((req = evhttp_request_new(evhttp_handle_request, http)) == NULL) return (-1); req->evcon = evcon; /* the request ends up owning the connection */ req->flags |= EVHTTP_REQ_OWN_CONNECTION; TAILQ_INSERT_TAIL(&evcon->requests, req, next); req->kind = EVHTTP_REQUEST; if ((req->remote_host = strdup(evcon->address)) == NULL) event_err(1, "%s: strdup", __func__); req->remote_port = evcon->port; evhttp_start_read(evcon); return (0); } void evhttp_get_request(struct evhttp *http, int fd, struct sockaddr *sa, socklen_t salen) { struct evhttp_connection *evcon; evcon = evhttp_get_request_connection(http, fd, sa, salen); if (evcon == NULL) return; /* the timeout can be used by the server to close idle connections */ if (http->timeout != -1) evhttp_connection_set_timeout(evcon, http->timeout); /* * if we want to accept more than one request on a connection, * we need to know which http server it belongs to. */ evcon->http_server = http; TAILQ_INSERT_TAIL(&http->connections, evcon, next); if (evhttp_associate_new_request_with_connection(evcon) == -1) evhttp_connection_free(evcon); } /* * Network helper functions that we do not want to export to the rest of * the world. */ #if 0 /* Unused */ static struct addrinfo * addr_from_name(char *address) { #ifdef HAVE_GETADDRINFO struct addrinfo ai, *aitop; int ai_result; memset(&ai, 0, sizeof(ai)); ai.ai_family = AF_INET; ai.ai_socktype = SOCK_RAW; ai.ai_flags = 0; if ((ai_result = getaddrinfo(address, NULL, &ai, &aitop)) != 0) { if ( ai_result == EAI_SYSTEM ) event_warn("getaddrinfo"); else event_warnx("getaddrinfo: %s", gai_strerror(ai_result)); } return (aitop); #else assert(0); return NULL; /* XXXXX Use gethostbyname, if this function is ever used. */ #endif } #endif static void name_from_addr(struct sockaddr *sa, socklen_t salen, char **phost, char **pport) { char ntop[NI_MAXHOST]; char strport[NI_MAXSERV]; int ni_result; #ifdef HAVE_GETNAMEINFO ni_result = getnameinfo(sa, salen, ntop, sizeof(ntop), strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV); if (ni_result != 0) { if (ni_result == EAI_SYSTEM) event_err(1, "getnameinfo failed"); else event_errx(1, "getnameinfo failed: %s", gai_strerror(ni_result)); return; } #else ni_result = fake_getnameinfo(sa, salen, ntop, sizeof(ntop), strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV); if (ni_result != 0) return; #endif *phost = strdup(ntop); *pport = strdup(strport); } /* Create a non-blocking socket and bind it */ /* todo: rename this function */ static int bind_socket_ai(struct addrinfo *ai, int reuse) { int fd, on = 1, r; int serrno; /* Create listen socket */ fd = socket(AF_INET, SOCK_STREAM, 0); if (fd == -1) { event_warn("socket"); return (-1); } if (evutil_make_socket_nonblocking(fd) < 0) goto out; #ifndef WIN32 if (fcntl(fd, F_SETFD, 1) == -1) { event_warn("fcntl(F_SETFD)"); goto out; } #endif setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, (void *)&on, sizeof(on)); if (reuse) { setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, (void *)&on, sizeof(on)); } if (ai != NULL) { r = bind(fd, ai->ai_addr, ai->ai_addrlen); if (r == -1) goto out; } return (fd); out: serrno = EVUTIL_SOCKET_ERROR(); EVUTIL_CLOSESOCKET(fd); EVUTIL_SET_SOCKET_ERROR(serrno); return (-1); } static struct addrinfo * make_addrinfo(const char *address, u_short port) { struct addrinfo *aitop = NULL; #ifdef HAVE_GETADDRINFO struct addrinfo ai; char strport[NI_MAXSERV]; int ai_result; memset(&ai, 0, sizeof(ai)); ai.ai_family = AF_INET; ai.ai_socktype = SOCK_STREAM; ai.ai_flags = AI_PASSIVE; /* turn NULL host name into INADDR_ANY */ evutil_snprintf(strport, sizeof(strport), "%d", port); if ((ai_result = getaddrinfo(address, strport, &ai, &aitop)) != 0) { if ( ai_result == EAI_SYSTEM ) event_warn("getaddrinfo"); else event_warnx("getaddrinfo: %s", gai_strerror(ai_result)); return (NULL); } #else static int cur; static struct addrinfo ai[2]; /* We will be returning the address of some of this memory so it has to last even after this call. */ if (++cur == 2) cur = 0; /* allow calling this function twice */ if (fake_getaddrinfo(address, &ai[cur]) < 0) { event_warn("fake_getaddrinfo"); return (NULL); } aitop = &ai[cur]; ((struct sockaddr_in *) aitop->ai_addr)->sin_port = htons(port); #endif return (aitop); } static int bind_socket(const char *address, u_short port, int reuse) { int fd; struct addrinfo *aitop = NULL; /* just create an unbound socket */ if (address == NULL && port == 0) return bind_socket_ai(NULL, 0); aitop = make_addrinfo(address, port); if (aitop == NULL) return (-1); fd = bind_socket_ai(aitop, reuse); #ifdef HAVE_GETADDRINFO freeaddrinfo(aitop); #else fake_freeaddrinfo(aitop); #endif return (fd); } static int socket_connect(int fd, const char *address, unsigned short port) { struct addrinfo *ai = make_addrinfo(address, port); int res = -1; if (ai == NULL) { event_debug(("%s: make_addrinfo: \"%s:%d\"", __func__, address, port)); return (-1); } if (connect(fd, ai->ai_addr, ai->ai_addrlen) == -1) { #ifdef WIN32 int tmp_error = WSAGetLastError(); if (tmp_error != WSAEWOULDBLOCK && tmp_error != WSAEINVAL && tmp_error != WSAEINPROGRESS) { goto out; } #else if (errno != EINPROGRESS) { goto out; } #endif } /* everything is fine */ res = 0; out: #ifdef HAVE_GETADDRINFO freeaddrinfo(ai); #else fake_freeaddrinfo(ai); #endif return (res); }