X-Git-Url: http://www.privoxy.org/gitweb/?p=privoxy.git;a=blobdiff_plain;f=jcc.c;h=056a6c1e9b1af98786ccd072ac4d47acec0e87a5;hp=e902e19a2145fba13304b45d27ad4b4bf9c6baeb;hb=42e4fa330b6bae707912dc050900fda316a5224f;hpb=95fe5bcbf0914d9800627d6f5d03dbae139295aa diff --git a/jcc.c b/jcc.c index e902e19a..056a6c1e 100644 --- a/jcc.c +++ b/jcc.c @@ -1,4 +1,4 @@ -const char jcc_rcs[] = "$Id: jcc.c,v 1.102 2006/09/06 13:03:04 fabiankeil Exp $"; +const char jcc_rcs[] = "$Id: jcc.c,v 1.127 2007/03/20 13:53:17 fabiankeil Exp $"; /********************************************************************* * * File : $Source: /cvsroot/ijbswa/current/jcc.c,v $ @@ -6,7 +6,7 @@ const char jcc_rcs[] = "$Id: jcc.c,v 1.102 2006/09/06 13:03:04 fabiankeil Exp $" * Purpose : Main file. Contains main() method, main loop, and * the main connection-handling function. * - * Copyright : Written by and Copyright (C) 2001 the SourceForge + * Copyright : Written by and Copyright (C) 2001-2007 the SourceForge * Privoxy team. http://www.privoxy.org/ * * Based on the Internet Junkbuster originally written @@ -33,6 +33,132 @@ const char jcc_rcs[] = "$Id: jcc.c,v 1.102 2006/09/06 13:03:04 fabiankeil Exp $" * * Revisions : * $Log: jcc.c,v $ + * Revision 1.127 2007/03/20 13:53:17 fabiankeil + * Log the source address for ACL-related connection drops. + * + * Revision 1.126 2007/03/17 15:20:05 fabiankeil + * New config option: enforce-blocks. + * + * Revision 1.125 2007/03/09 14:12:00 fabiankeil + * - Move null byte check into separate function. + * - Don't confuse the client with error pages + * if a CONNECT request was already confirmed. + * + * Revision 1.124 2007/02/23 14:59:54 fabiankeil + * Speed up NULL byte escaping and only log the complete + * NULL byte requests with header debugging enabled. + * + * Revision 1.123 2007/02/21 18:42:10 fabiankeil + * Answer requests that contain NULL bytes with + * a custom response instead of waiting for more + * data until the client eventually hangs up. + * + * Revision 1.122 2007/02/07 11:12:02 fabiankeil + * - Move delivery and logging of crunched responses + * from chat() into send_crunch_response(). + * - Display the reason for generating http_responses. + * - Log the content length for LOG_LEVEL_CLF correctly + * (still incorrect for some fixed responses). + * - Reword an incorrect comment about + * treat-forbidden-connects-like-blocks violating + * the specs. + * - Add some log messages. + * + * Revision 1.121 2007/01/27 10:52:56 fabiankeil + * Move mutex initialization into separate + * function and exit in case of errors. + * + * Revision 1.120 2007/01/26 14:18:42 fabiankeil + * - Start to reduce chat()'s line count and move + * parts of it into separate functions. + * - Add "HTTP/1.1 100 Continue" hack for BR 756734. + * + * Revision 1.119 2007/01/25 14:02:30 fabiankeil + * - Add Proxy-Agent header to HTTP snippets that are + * supposed to reach HTTP clients only. + * - Made a few CONNECT log messages more descriptive. + * - Catch completely empty server responses (as seen + * with Tor's fake ".noconnect" top level domain). + * - Use shiny new "forwarding-failed" template for socks errors. + * + * Revision 1.118 2007/01/07 07:43:43 joergs + * AmigaOS4 support added. + * + * Revision 1.117 2006/12/31 17:56:37 fabiankeil + * Added config option accept-intercepted-requests + * and disabled it by default. + * + * Revision 1.116 2006/12/29 19:08:22 fabiankeil + * Reverted parts of my last commit + * to keep error handling working. + * + * Revision 1.115 2006/12/29 17:38:57 fabiankeil + * Fixed gcc43 conversion warnings. + * + * Revision 1.114 2006/12/27 18:52:02 fabiankeil + * Fix -pedantic ISO C warning about converting + * from function pointer to object pointer. + * + * Revision 1.113 2006/12/26 17:38:50 fabiankeil + * Silence compiler warning I introduced with my last commit. + * + * Revision 1.112 2006/12/26 17:31:41 fabiankeil + * Mutex protect rand() if POSIX threading + * is used, warn the user if that's not possible + * and stop using it on _WIN32 where it could + * cause crashes. + * + * Revision 1.111 2006/12/23 16:15:06 fabiankeil + * Don't prevent core dumps by catching SIGABRT. + * It's rude and makes debugging unreasonable painful. + * + * Revision 1.110 2006/12/13 14:52:53 etresoft + * Fix build failure on MacOS X. Global symbols can be either static or extern, but not both. + * + * Revision 1.109 2006/12/06 19:41:40 fabiankeil + * Privoxy is now able to run as intercepting + * proxy in combination with any packet filter + * that does the port redirection. The destination + * is extracted from the "Host:" header which + * should be available for nearly all requests. + * + * Moved HTTP snipplets into jcc.c. + * Added error message for gopher proxy requests. + * + * Revision 1.108 2006/11/28 15:38:51 fabiankeil + * Only unlink the pidfile if it's actually used. + * + * Change order of interception checks to make + * it possible to block or redirect requests for + * the cgi pages. + * + * Revision 1.107 2006/11/13 19:05:51 fabiankeil + * Make pthread mutex locking more generic. Instead of + * checking for OSX and OpenBSD, check for FEATURE_PTHREAD + * and use mutex locking unless there is an _r function + * available. Better safe than sorry. + * + * Fixes "./configure --disable-pthread" and should result + * in less threading-related problems on pthread-using platforms, + * but it still doesn't fix BR#1122404. + * + * Revision 1.106 2006/11/06 19:58:23 fabiankeil + * Move pthread.h inclusion from jcc.c to jcc.h. + * Fixes build on x86-freebsd1 (FreeBSD 5.4-RELEASE). + * + * Revision 1.105 2006/11/06 14:26:02 fabiankeil + * Don't exit after receiving the second SIGHUP on Solaris. + * + * Fixes BR 1052235, but the same problem may exist on other + * systems. Once 3.0.6 is out we should use sigset() + * where available and see if it breaks anything. + * + * Revision 1.104 2006/09/23 13:26:38 roro + * Replace TABs by spaces in source code. + * + * Revision 1.103 2006/09/21 12:54:43 fabiankeil + * Fix +redirect{}. Didn't work with -fast-redirects. + * * Revision 1.102 2006/09/06 13:03:04 fabiankeil * Respond with 400 and a short text message * if the client tries to use Privoxy as FTP proxy. @@ -78,7 +204,8 @@ const char jcc_rcs[] = "$Id: jcc.c,v 1.102 2006/09/06 13:03:04 fabiankeil Exp $" * Windows service integration * * Revision 1.95 2006/08/03 02:46:41 david__schmidt - * Incorporate Fabian Keil's patch work: http://www.fabiankeil.de/sourcecode/privoxy/ + * Incorporate Fabian Keil's patch work: +http://www.fabiankeil.de/sourcecode/privoxy/ * * Revision 1.94 2006/07/18 14:48:46 david__schmidt * Reorganizing the repository: swapping out what was HEAD (the old 3.1 branch) @@ -668,10 +795,7 @@ const char jcc_rcs[] = "$Id: jcc.c,v 1.102 2006/09/06 13:03:04 fabiankeil Exp $" #include #include #include - -#ifdef FEATURE_PTHREAD -#include -#endif /* def FEATURE_PTHREAD */ +#include #ifdef _WIN32 # ifndef FEATURE_PTHREAD @@ -781,24 +905,30 @@ static int32 server_thread(void *data); #define sleep(N) DosSleep(((N) * 100)) #endif -#if defined(OSX_DARWIN) || defined(__OpenBSD__) -#ifdef OSX_DARWIN -/* - * Hit OSX over the head with a hammer. Protect all *_r functions. - */ +#ifdef FEATURE_PTHREAD +pthread_mutex_t log_mutex; +pthread_mutex_t log_init_mutex; + +#ifndef HAVE_GMTIME_R pthread_mutex_t gmtime_mutex; +#endif /* ndef HAVE_GMTIME_R */ + +#ifndef HAVE_LOCALTIME_R pthread_mutex_t localtime_mutex; -#endif /* def OSX_DARWIN */ -/* - * Protect only the resolve functions for OpenBSD. - */ +#endif /* ndef HAVE_GMTIME_R */ + +#ifndef HAVE_GETHOSTBYADDR_R pthread_mutex_t gethostbyaddr_mutex; +#endif /* ndef HAVE_GETHOSTBYADDR_R */ + +#ifndef HAVE_GETHOSTBYNAME_R pthread_mutex_t gethostbyname_mutex; -#endif /* defined(OSX_DARWIN) || defined(__OpenBSD__) */ +#endif /* ndef HAVE_GETHOSTBYNAME_R */ + +#ifndef HAVE_RANDOM +pthread_mutex_t rand_mutex; +#endif /* ndef HAVE_RANDOM */ -#ifdef FEATURE_PTHREAD -pthread_mutex_t log_mutex; -pthread_mutex_t log_init_mutex; #endif /* FEATURE_PTHREAD */ #if defined(unix) || defined(__EMX__) @@ -817,6 +947,53 @@ static const char VANILLA_WAFER[] = "Take_notice_that_I_refuse_to_be_bound_by_any_license_condition_" "(copyright_or_otherwise)_applying_to_any_cookie._"; +/* HTTP snipplets. */ +const char CSUCCEED[] = + "HTTP/1.0 200 Connection established\n" + "Proxy-Agent: Privoxy/" VERSION "\r\n\r\n"; + +const char CHEADER[] = + "HTTP/1.0 400 Invalid header received from browser\r\n" + "Connection: close\r\n\r\n" + "Invalid header received from browser.\r\n"; + +const char CFORBIDDEN[] = + "HTTP/1.0 403 Connection not allowable\r\n" + "Proxy-Agent: Privoxy " VERSION "\r\n" + "X-Hint: If you read this message interactively, then you know why this happens ,-)\r\n" + "Connection: close\r\n\r\n"; + +const char FTP_RESPONSE[] = + "HTTP/1.0 400 Invalid request received from browser\r\n" + "Connection: close\r\n\r\n" + "Invalid request. Privoxy doesn't support FTP.\r\n"; + +const char GOPHER_RESPONSE[] = + "HTTP/1.0 400 Invalid request received from browser\r\n" + "Connection: close\r\n\r\n" + "Invalid request. Privoxy doesn't support gopher.\r\n"; + +/* XXX: should be a template */ +const char MISSING_DESTINATION_RESPONSE[] = + "HTTP/1.0 400 Bad request received from browser\r\n" + "Proxy-Agent: Privoxy " VERSION "\r\n" + "Connection: close\r\n\r\n" + "Bad request. Privoxy was unable to extract the destination.\r\n"; + +/* XXX: should be a template */ +const char NO_SERVER_DATA_RESPONSE[] = + "HTTP/1.0 502 Server or forwarder response empty\r\n" + "Proxy-Agent: Privoxy " VERSION "\r\n" + "Connection: close\r\n\r\n" + "Empty server or forwarder response.\r\n" + "The connection was closed without sending any data.\r\n"; + +/* XXX: should be a template */ +const char NULL_BYTE_RESPONSE[] = + "HTTP/1.0 400 Bad request received from browser\r\n" + "Proxy-Agent: Privoxy " VERSION "\r\n" + "Connection: close\r\n\r\n" + "Bad request. Null byte(s) before end of request.\r\n"; #if !defined(_WIN32) && !defined(__OS2__) && !defined(AMIGA) /********************************************************************* @@ -824,7 +1001,7 @@ static const char VANILLA_WAFER[] = * Function : sig_handler * * Description : Signal handler for different signals. - * Exit gracefully on ABRT, TERM and INT + * Exit gracefully on TERM and INT * or set a flag that will cause the errlog * to be reopened by the main thread on HUP. * @@ -838,12 +1015,14 @@ static void sig_handler(int the_signal) { switch(the_signal) { - case SIGABRT: case SIGTERM: case SIGINT: log_error(LOG_LEVEL_INFO, "exiting by signal %d .. bye", the_signal); #if defined(unix) - unlink(pidfile); + if(pidfile) + { + unlink(pidfile); + } #endif /* unix */ exit(the_signal); break; @@ -865,6 +1044,432 @@ static void sig_handler(int the_signal) #endif +/********************************************************************* + * + * Function : client_protocol_is_unsupported + * + * Description : Checks if the client used a known unsupported + * protocol and deals with it by sending an error + * response. + * + * Parameters : + * 1 : csp = Current client state (buffers, headers, etc...) + * 2 : req = the first request line send by the client + * + * Returns : TRUE if an error response has been generated, or + * FALSE if the request doesn't look invalid. + * + *********************************************************************/ +int client_protocol_is_unsupported(const struct client_state *csp, char *req) +{ + char buf[BUFFER_SIZE]; + + /* + * If it's a FTP or gopher request, we don't support it. + * + * These checks are better than nothing, but they might + * not work in all configurations and some clients might + * have problems digesting the answer. + * + * They should, however, never cause more problems than + * Privoxy's old behaviour (returning the misleading HTML + * error message: + * + * "Could not resolve http://(ftp|gopher)://example.org"). + */ + if (!strncmpic(req, "GET ftp://", 10) || !strncmpic(req, "GET gopher://", 13)) + { + if (!strncmpic(req, "GET ftp://", 10)) + { + strcpy(buf, FTP_RESPONSE); + log_error(LOG_LEVEL_ERROR, "%s tried to use Privoxy as FTP proxy: %s", + csp->ip_addr_str, req); + } + else + { + strcpy(buf, GOPHER_RESPONSE); + log_error(LOG_LEVEL_ERROR, "%s tried to use Privoxy as gopher proxy: %s", + csp->ip_addr_str, req); + } + log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" 400 0", csp->ip_addr_str, req); + freez(req); + write_socket(csp->cfd, buf, strlen(buf)); + + return TRUE; + } + + return FALSE; +} + + +/********************************************************************* + * + * Function : get_request_destination_elsewhere + * + * Description : If the client's request was redirected into + * Privoxy without the client's knowledge, + * the request line lacks the destination host. + * + * This function tries to get it elsewhere, + * provided accept-intercepted-requests is enabled. + * + * "Elsewhere" currently only means "Host: header", + * but in the future we may ask the redirecting + * packet filter to look the destination up. + * + * If the destination stays unknown, an error + * response is send to the client and headers + * are freed so that chat() can return directly. + * + * Parameters : + * 1 : csp = Current client state (buffers, headers, etc...) + * 2 : headers = a header list + * + * Returns : JB_ERR_OK if the destination is now known, or + * JB_ERR_PARSE if it isn't. + * + *********************************************************************/ +jb_err get_request_destination_elsewhere(struct client_state *csp, struct list *headers) +{ + char buf[BUFFER_SIZE]; + char *req; + + if (!(csp->config->feature_flags & RUNTIME_FEATURE_ACCEPT_INTERCEPTED_REQUESTS)) + { + log_error(LOG_LEVEL_ERROR, "%s's request: \'%s\' is invalid." + " Privoxy isn't configured to accept intercepted requests.", + csp->ip_addr_str, csp->http->cmd); + /* XXX: Use correct size */ + log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" 400 0", + csp->ip_addr_str, csp->http->cmd); + + strcpy(buf, CHEADER); + write_socket(csp->cfd, buf, strlen(buf)); + destroy_list(headers); + + return JB_ERR_PARSE; + } + else if (JB_ERR_OK == get_destination_from_headers(headers, csp->http)) + { + /* Split the domain we just got for pattern matching */ + init_domain_components(csp->http); + + return JB_ERR_OK; + } + else + { + /* We can't work without destination. Go spread the news.*/ + + req = list_to_text(headers); + chomp(req); + /* XXX: Use correct size */ + log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" 400 0", + csp->ip_addr_str, csp->http->cmd); + log_error(LOG_LEVEL_ERROR, + "Privoxy was unable to get the destination for %s's request:\n%s\n%s", + csp->ip_addr_str, csp->http->cmd, req); + freez(req); + + strcpy(buf, MISSING_DESTINATION_RESPONSE); + write_socket(csp->cfd, buf, strlen(buf)); + destroy_list(headers); + + return JB_ERR_PARSE; + } + /* + * TODO: If available, use PF's ioctl DIOCNATLOOK as last resort + * to get the destination IP address, use it as host directly + * or do a reverse DNS lookup first. + */ +} + + +/********************************************************************* + * + * Function : get_server_headers + * + * Description : Parses server headers in iob and fills them + * into csp->headers so that they can later be + * handled by sed(). + * + * Parameters : + * 1 : csp = Current client state (buffers, headers, etc...) + * + * Returns : JB_ERR_OK if everything went fine, or + * JB_ERR_PARSE if the headers were incomplete. + * + *********************************************************************/ +jb_err get_server_headers(struct client_state *csp) +{ + int continue_hack_in_da_house = 0; + char * header; + + while (((header = get_header(csp)) != NULL) || continue_hack_in_da_house) + { + if (header == NULL) + { + /* + * continue hack in da house. Ignore the ending of + * this head and continue enlisting header lines. + * The reason is described below. + */ + enlist(csp->headers, ""); + continue_hack_in_da_house = 0; + continue; + } + else if (0 == strncmpic(header, "HTTP/1.1 100", 12)) + { + /* + * It's a bodyless continue response, don't + * stop header parsing after reaching it's end. + * + * As a result Privoxy will concatenate the + * next response's head and parse and deliver + * the headers as if they belonged to one request. + * + * The client will separate them because of the + * empty line between them. + * + * XXX: What we're doing here is clearly against + * the intended purpose of the continue header, + * and under some conditions (HTTP/1.0 client request) + * it's a standard violation. + * + * Anyway, "sort of against the spec" is preferable + * to "always getting confused by Continue responses" + * (Privoxy's behaviour before this hack was added) + */ + log_error(LOG_LEVEL_HEADER, "Continue hack in da house."); + continue_hack_in_da_house = 1; + } + else if (*header == '\0') + { + /* + * If the header is empty, but the Continue hack + * isn't active, we can assume that we reached the + * end of the buffer before we hit the end of the + * head. + * + * Inform the caller an let it decide how to handle it. + */ + return JB_ERR_PARSE; + } + + /* Enlist header */ + if (JB_ERR_MEMORY == enlist(csp->headers, header)) + { + /* + * XXX: Should we quit the request and return a + * out of memory error page instead? + */ + log_error(LOG_LEVEL_ERROR, + "Out of memory while enlisting server headers. %s lost.", + header); + } + freez(header); + } + + return JB_ERR_OK; +} + + +/********************************************************************* + * + * Function : crunch_reason + * + * Description : Translates the crunch reason code into a string. + * + * Parameters : + * 1 : rsp = a http_response + * + * Returns : A string with the crunch reason or an error description. + * + *********************************************************************/ +const char *crunch_reason(const struct http_response *rsp) +{ + char * reason = NULL; + + assert(rsp != NULL); + if (rsp == NULL) + { + return "Internal error while searching for crunch reason"; + } + + switch (rsp->reason) + { + case RSP_REASON_UNSUPPORTED: + reason = "Unsupported HTTP feature"; + break; + case RSP_REASON_BLOCKED: + reason = "Blocked"; + break; + case RSP_REASON_UNTRUSTED: + reason = "Untrusted"; + break; + case RSP_REASON_REDIRECTED: + reason = "Redirected"; + break; + case RSP_REASON_CGI_CALL: + reason = "CGI Call"; + break; + case RSP_REASON_NO_SUCH_DOMAIN: + reason = "DNS failure"; + break; + case RSP_REASON_FORWARDING_FAILED: + reason = "Forwarding failed"; + break; + case RSP_REASON_CONNECT_FAILED: + reason = "Connection failure"; + break; + case RSP_REASON_OUT_OF_MEMORY: + reason = "Out of memory (may mask other reasons)"; + break; + default: + reason = "No reason recorded"; + break; + } + + return reason; +} + + +/********************************************************************* + * + * Function : send_crunch_response + * + * Description : Delivers already prepared response for + * intercepted requests, logs the interception + * and frees the response. + * + * Parameters : + * 1 : csp = Current client state (buffers, headers, etc...) + * 1 : rsp = Fully prepared response. Will be freed on exit. + * + * Returns : Nothing. + * + *********************************************************************/ +void send_crunch_response(struct client_state *csp, struct http_response *rsp) +{ + const struct http_request *http = csp->http; + char status_code[4]; + + assert(rsp != NULL); + assert(rsp->head != NULL); + + if (rsp == NULL) + { + /* + * Not supposed to happen. If it does + * anyway, treat it as an unknown error. + */ + cgi_error_unknown(csp, rsp, RSP_REASON_INTERNAL_ERROR); + /* return code doesn't matter */ + } + + if (rsp == NULL) + { + /* If rsp is still NULL, we have serious internal problems. */ + log_error(LOG_LEVEL_FATAL, + "NULL response in send_crunch_response and cgi_error_unknown failed as well."); + } + + /* + * Extract the status code from the actual head + * that was send to the client. It is the only + * way to get it right for all requests, including + * the fixed ones for out-of-memory problems. + * + * A head starts like this: 'HTTP/1.1 200...' + * 0123456789|11 + * 10 + */ + status_code[0] = rsp->head[9]; + status_code[1] = rsp->head[10]; + status_code[2] = rsp->head[11]; + status_code[3] = '\0'; + + /* Write the answer to the client */ + if (write_socket(csp->cfd, rsp->head, rsp->head_length) + || write_socket(csp->cfd, rsp->body, rsp->content_length)) + { + /* There is nothing we can do about it. */ + log_error(LOG_LEVEL_ERROR, "write to: %s failed: %E", csp->http->host); + } + + /* Log that the request was crunched and why. */ + log_error(LOG_LEVEL_GPC, "%s%s crunch! (%s)", + http->hostport, http->path, crunch_reason(rsp)); + log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" %s %d", + csp->ip_addr_str, http->ocmd, status_code, rsp->content_length); + + /* Clean up and return */ + if (cgi_error_memory() != rsp) + { + free_http_response(rsp); + } + return; +} + + +/********************************************************************* + * + * Function : request_contains_null_bytes + * + * Description : Checks for NULL bytes in the request and sends + * an error message to the client if any were found. + * + * Parameters : + * 1 : csp = Current client state (buffers, headers, etc...) + * 2 : buf = Data from the client's request to check. + * 3 : len = The data length. + * + * Returns : TRUE if the request contained one or more NULL bytes, or + * FALSE otherwise. + * + *********************************************************************/ +int request_contains_null_bytes(const struct client_state *csp, char *buf, int len) +{ + size_t c_len; /* Request lenght when treated as C string */ + + c_len = strlen(buf); + + if (c_len < len) + { + /* + * Null byte(s) found. Log the request, + * return an error response and hang up. + */ + size_t tmp_len = c_len; + + do + { + /* + * Replace NULL byte(s) with '°' characters + * so the request can be logged as string. + * XXX: Is there a better replacement character? + */ + buf[tmp_len]='°'; + tmp_len += strlen(buf+tmp_len); + } while (tmp_len < len); + + log_error(LOG_LEVEL_ERROR, "%s\'s request contains at least one NULL byte " + "(length=%d, strlen=%d).", csp->ip_addr_str, len, c_len); + log_error(LOG_LEVEL_HEADER, + "Offending request data with NULL bytes turned into \'°\' characters: %s", buf); + + strcpy(buf, NULL_BYTE_RESPONSE); + write_socket(csp->cfd, buf, strlen(buf)); + + /* XXX: Log correct size */ + log_error(LOG_LEVEL_CLF, "%s - - [%T] \"Invalid request\" 400 0", csp->ip_addr_str); + + return TRUE; + } + + return FALSE; +} + + /********************************************************************* * * Function : chat @@ -875,6 +1480,9 @@ static void sig_handler(int the_signal) * function returns, the caller must close the client * socket handle. * + * FIXME: chat is nearly thousand lines long. + * Ridiculous. + * * Parameters : * 1 : csp = Current client state (buffers, headers, etc...) * @@ -916,12 +1524,12 @@ static void chat(struct client_state *csp) jb_socket maxfd; int server_body; int ms_iis5_hack = 0; - int byte_count = 0; - unsigned int forwarded_connect_retries = 0; - unsigned int max_forwarded_connect_retries = csp->config->forwarded_connect_retries; + size_t byte_count = 0; + int forwarded_connect_retries = 0; + int max_forwarded_connect_retries = csp->config->forwarded_connect_retries; const struct forward_spec * fwd; struct http_request *http; - int len; /* for buffer sizes */ + int len; /* for buffer sizes (and negative error codes) */ #ifdef FEATURE_KILL_POPUPS int block_popups; /* bool, 1==will block popups */ int block_popups_now = 0; /* bool, 1==currently blocking popups */ @@ -937,8 +1545,14 @@ static void chat(struct client_state *csp) /* Skeleton for HTTP response, if we should intercept the request */ struct http_response *rsp; + /* Temporary copy of the client's headers before they get enlisted in csp->headers */ + struct list header_list; + struct list *headers = &header_list; + http = csp->http; + memset(buf, 0, sizeof(buf)); + /* * Read the client's request. Note that since we're not using select() we * could get blocked here if a client connected, then didn't say anything! @@ -946,10 +1560,16 @@ static void chat(struct client_state *csp) for (;;) { - len = read_socket(csp->cfd, buf, sizeof(buf)); + len = read_socket(csp->cfd, buf, sizeof(buf)-1); if (len <= 0) break; /* error! */ - + + if (request_contains_null_bytes(csp, buf, len)) + { + /* NULL bytes found and dealt with, just hang up. */ + return; + } + /* * If there is no memory left for buffering the * request, there is nothing we can do but hang up @@ -971,21 +1591,49 @@ static void chat(struct client_state *csp) continue; /* more to come! */ } + /* Does the request line look invalid? */ + if (client_protocol_is_unsupported(csp, req)) + { + /* + * Yes. The request has already been + * answered with a error response, the buffers + * were freed and we're done with chatting. + */ + return; + } + #ifdef FEATURE_FORCE_LOAD - /* If this request contains the FORCE_PREFIX, - * better get rid of it now and set the force flag --oes + /* + * If this request contains the FORCE_PREFIX and blocks + * aren't enforced, get rid of it and set the force flag. */ - if (strstr(req, FORCE_PREFIX)) { - strclean(req, FORCE_PREFIX); - log_error(LOG_LEVEL_FORCE, "Enforcing request \"%s\".\n", req); - csp->flags |= CSP_FLAG_FORCED; + if (csp->config->feature_flags & RUNTIME_FEATURE_ENFORCE_BLOCKS) + { + log_error(LOG_LEVEL_FORCE, + "Ignored force prefix in request: \"%s\".", req); + } + else + { + strclean(req, FORCE_PREFIX); + log_error(LOG_LEVEL_FORCE, "Enforcing request: \"%s\".", req); + csp->flags |= CSP_FLAG_FORCED; + } } #endif /* def FEATURE_FORCE_LOAD */ - parse_http_request(req, http, csp); + switch( parse_http_request(req, http, csp) ) + { + case JB_ERR_MEMORY: + log_error(LOG_LEVEL_ERROR, "Out of memory while parsing request."); + break; + case JB_ERR_PARSE: + log_error(LOG_LEVEL_ERROR, "Couldn't parse request: %s.", req); + break; + } + freez(req); break; } @@ -994,23 +1642,64 @@ static void chat(struct client_state *csp) { strcpy(buf, CHEADER); write_socket(csp->cfd, buf, strlen(buf)); - - log_error(LOG_LEVEL_CLF, "%s - - [%T] \" \" 400 0", csp->ip_addr_str); + /* XXX: Use correct size */ + log_error(LOG_LEVEL_CLF, "%s - - [%T] \"Invalid request\" 400 0", csp->ip_addr_str); + log_error(LOG_LEVEL_ERROR, "Invalid header received from %s.", csp->ip_addr_str); free_http_request(http); return; } - if (!strncmpic(http->cmd, "GET ftp://", 10)) + /* grab the rest of the client's headers */ + init_list(headers); + for (;;) { - strcpy(buf, FTP_RESPONSE); - write_socket(csp->cfd, buf, strlen(buf)); + if ( ( ( p = get_header(csp) ) != NULL) && ( *p == '\0' ) ) + { + len = read_socket(csp->cfd, buf, sizeof(buf)); + if (len <= 0) + { + log_error(LOG_LEVEL_ERROR, "read from client failed: %E"); + return; + } + + /* + * If there is no memory left for buffering the + * request, there is nothing we can do but hang up + */ + if (add_to_iob(csp, buf, len)) + { + return; + } + continue; + } - log_error(LOG_LEVEL_ERROR, "%s tried to use Privoxy as FTP proxy: %s", - csp->ip_addr_str, http->cmd); + if (p == NULL) break; + + enlist(headers, p); + freez(p); - free_http_request(http); - return; + } + + if (http->host == NULL) + { + /* + * If we still don't know the request destination, + * the request is invalid or the client uses + * Privoxy without it's knowledge. + */ + if (JB_ERR_OK != get_request_destination_elsewhere(csp, headers)) + { + /* + * Our attempts to get the request destination + * elsewhere failed or Privoxy is configured + * to only accept proxy requests. + * + * An error response has already been send + * and we're done here. + */ + return; + } } /* decide how to route the HTTP request */ @@ -1086,7 +1775,10 @@ static void chat(struct client_state *csp) { if (csp->action->flags & ACTION_TREAT_FORBIDDEN_CONNECTS_LIKE_BLOCKS) { - /* The response will violate the specs, but makes unblocking easier. */ + /* + * The response may confuse some clients, + * but makes unblocking easier. + */ log_error(LOG_LEVEL_ERROR, "Marking suspicious CONNECT request from %s for blocking.", csp->ip_addr_str); csp->action->flags |= ACTION_BLOCK; @@ -1161,6 +1853,9 @@ static void chat(struct client_state *csp) } enlist(csp->headers, http->cmd); + /* Append the previously read headers */ + list_append_list_unique(csp->headers, headers); + destroy_list(headers); /* * If the user has not supplied any wafers, and the user has not @@ -1184,36 +1879,6 @@ static void chat(struct client_state *csp) jpeg_inspect = ((csp->action->flags & ACTION_JPEG_INSPECT) != 0); - /* grab the rest of the client's headers */ - - for (;;) - { - if ( ( ( p = get_header(csp) ) != NULL) && ( *p == '\0' ) ) - { - len = read_socket(csp->cfd, buf, sizeof(buf)); - if (len <= 0) - { - log_error(LOG_LEVEL_ERROR, "read from client failed: %E"); - return; - } - - /* - * If there is no memory left for buffering the - * request, there is nothing we can do but hang up - */ - if (add_to_iob(csp, buf, len)) - { - return; - } - continue; - } - - if (p == NULL) break; - - enlist(csp->headers, p); - freez(p); - } - /* * We have a request. Now, check to see if we need to * intercept it, i.e. If .. @@ -1223,9 +1888,6 @@ static void chat(struct client_state *csp) /* We may not forward the request by rfc2616 sect 14.31 */ (NULL != (rsp = direct_response(csp))) - /* or a CGI call was detected and answered */ - || (NULL != (rsp = dispatch_cgi(csp))) - /* or we are enabled and... */ || (IS_ENABLED_AND ( @@ -1237,31 +1899,30 @@ static void chat(struct client_state *csp) || ( NULL != (rsp = trust_url(csp))) #endif /* def FEATURE_TRUST */ - /* ..or a fast redirect kicked in */ -#ifdef FEATURE_FAST_REDIRECTS + /* ..or a redirect kicked in */ || ( NULL != (rsp = redirect_url(csp))) -#endif /* def FEATURE_FAST_REDIRECTS */ )) - ) - { - /* Write the answer to the client */ - if (write_socket(csp->cfd, rsp->head, rsp->head_length) - || write_socket(csp->cfd, rsp->body, rsp->content_length)) - { - log_error(LOG_LEVEL_ERROR, "write to: %s failed: %E", http->host); - } + /* + * .. or a CGI call was detected and answered. + * + * This check comes last to give the user the power + * to deny acces to some (or all) of the cgi pages. + */ + || (NULL != (rsp = dispatch_cgi(csp))) + + ) + { + /* + * Deliver, log and free the interception + * response. Afterwards we're done here. + */ + send_crunch_response(csp, rsp); #ifdef FEATURE_STATISTICS /* Count as a rejected request */ csp->flags |= CSP_FLAG_REJECTED; #endif /* def FEATURE_STATISTICS */ - /* Log (FIXME: All intercept reasons appear as "crunch" with Status 200) */ - log_error(LOG_LEVEL_GPC, "%s%s crunch!", http->hostport, http->path); - log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" 200 3", csp->ip_addr_str, http->ocmd); - - /* Clean up and return */ - free_http_response(rsp); return; } @@ -1291,48 +1952,39 @@ static void chat(struct client_state *csp) while ( (csp->sfd = forwarded_connect(fwd, http, csp)) && (errno == EINVAL) && (forwarded_connect_retries++ < max_forwarded_connect_retries)) { - log_error(LOG_LEVEL_ERROR, "failed request #%u to connect to %s. Trying again.", + log_error(LOG_LEVEL_ERROR, "failed request #%u to connect to %s. Trying again.", forwarded_connect_retries, http->hostport); } if (csp->sfd == JB_INVALID_SOCKET) { - log_error(LOG_LEVEL_CONNECT, "connect to: %s failed: %E", - http->hostport); - - if (errno == EINVAL) + if (fwd->type != SOCKS_NONE) + { + /* Socks error. */ + rsp = error_response(csp, "forwarding-failed", errno); + } + else if (errno == EINVAL) { rsp = error_response(csp, "no-such-domain", errno); - - log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" 404 0", - csp->ip_addr_str, http->ocmd); } else { rsp = error_response(csp, "connect-failed", errno); - - log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" 503 0", - csp->ip_addr_str, http->ocmd); + log_error(LOG_LEVEL_CONNECT, "connect to: %s failed: %E", + http->hostport); } /* Write the answer to the client */ - if(rsp) + if(rsp != NULL) { - if (write_socket(csp->cfd, rsp->head, rsp->head_length) - || write_socket(csp->cfd, rsp->body, rsp->content_length)) - { - log_error(LOG_LEVEL_ERROR, "write to: %s failed: %E", http->host); - } + send_crunch_response(csp, rsp); } - free_http_response(rsp); freez(hdr); return; } - log_error(LOG_LEVEL_CONNECT, "OK"); - if (fwd->forward_host || (http->ssl == 0)) { /* write the client's (modified) header to the server @@ -1345,21 +1997,13 @@ static void chat(struct client_state *csp) log_error(LOG_LEVEL_CONNECT, "write header to: %s failed: %E", http->hostport); - log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" 503 0", - csp->ip_addr_str, http->ocmd); - rsp = error_response(csp, "connect-failed", errno); if(rsp) { - if (write_socket(csp->cfd, rsp->head, rsp->head_length) - || write_socket(csp->cfd, rsp->body, rsp->content_length)) - { - log_error(LOG_LEVEL_ERROR, "write to: %s failed: %E", http->host); - } + send_crunch_response(csp, rsp); } - free_http_response(rsp); freez(hdr); return; } @@ -1371,9 +2015,6 @@ static void chat(struct client_state *csp) * so just send the "connect succeeded" message to the * client, flush the rest, and get out of the way. */ - log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" 200 2\n", - csp->ip_addr_str, http->ocmd); - if (write_socket(csp->cfd, CSUCCEED, sizeof(CSUCCEED)-1)) { freez(hdr); @@ -1382,6 +2023,8 @@ static void chat(struct client_state *csp) IOB_RESET(csp); } + log_error(LOG_LEVEL_CONNECT, "to %s successful", http->hostport); + /* we're finished with the client's header */ freez(hdr); @@ -1452,21 +2095,25 @@ static void chat(struct client_state *csp) { log_error(LOG_LEVEL_ERROR, "read from: %s failed: %E", http->host); - log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" 503 0", - csp->ip_addr_str, http->ocmd); + if (http->ssl && (fwd->forward_host == NULL)) + { + /* + * Just hang up. We already confirmed the client's CONNECT + * request with status code 200 and unencrypted content is + * no longer welcome. + */ + log_error(LOG_LEVEL_ERROR, + "CONNECT already confirmed. Unable to tell the client about the problem."); + return; + } rsp = error_response(csp, "connect-failed", errno); if(rsp) { - if (write_socket(csp->cfd, rsp->head, rsp->head_length) - || write_socket(csp->cfd, rsp->body, rsp->content_length)) - { - log_error(LOG_LEVEL_ERROR, "write to: %s failed: %E", http->host); - } + send_crunch_response(csp, rsp); } - free_http_response(rsp); return; } @@ -1520,7 +2167,7 @@ static void chat(struct client_state *csp) */ if (NULL == (p = (*content_filter)(csp))) { - csp->content_length = csp->iob->eod - csp->iob->cur; + csp->content_length = (size_t)(csp->iob->eod - csp->iob->cur); } hdr = sed(server_patterns_light, NULL, csp); @@ -1551,7 +2198,8 @@ static void chat(struct client_state *csp) * This is NOT the body, so * Let's pretend the server just sent us a blank line. */ - len = sprintf(buf, "\r\n"); + snprintf(buf, sizeof(buf), "\r\n"); + len = (int)strlen(buf); /* * Now, let the normal header parsing algorithm below do its @@ -1592,12 +2240,8 @@ static void chat(struct client_state *csp) */ log_error(LOG_LEVEL_ERROR, "Out of memory while trying to flush."); rsp = cgi_error_memory(); + send_crunch_response(csp, rsp); - if (write_socket(csp->cfd, rsp->head, rsp->head_length) - || write_socket(csp->cfd, rsp->body, rsp->content_length)) - { - log_error(LOG_LEVEL_ERROR, "write to: %s failed: %E", http->host); - } return; } @@ -1605,7 +2249,7 @@ static void chat(struct client_state *csp) if (write_socket(csp->cfd, hdr, hdrlen) || ((flushed = flush_socket(csp->cfd, csp)) < 0) - || (write_socket(csp->cfd, buf, (size_t) len))) + || (write_socket(csp->cfd, buf, (size_t)len))) { log_error(LOG_LEVEL_CONNECT, "Flush header and buffers to client failed: %E"); @@ -1613,7 +2257,7 @@ static void chat(struct client_state *csp) return; } - byte_count += hdrlen + flushed + len; + byte_count += hdrlen + (size_t)flushed + (size_t)len; freez(hdr); content_filter = NULL; server_body = 1; @@ -1628,7 +2272,7 @@ static void chat(struct client_state *csp) return; } } - byte_count += len; + byte_count += (size_t)len; continue; } else @@ -1647,35 +2291,13 @@ static void chat(struct client_state *csp) { log_error(LOG_LEVEL_ERROR, "Out of memory while looking for end of server headers."); rsp = cgi_error_memory(); - - if (write_socket(csp->cfd, rsp->head, rsp->head_length) - || write_socket(csp->cfd, rsp->body, rsp->content_length)) - { - log_error(LOG_LEVEL_ERROR, "write to: %s failed: %E", http->host); - } - return; - } - - /* get header lines from the iob */ + send_crunch_response(csp, rsp); - while ((p = get_header(csp)) != NULL) - { - if (*p == '\0') - { - /* see following note */ - break; - } - enlist(csp->headers, p); - freez(p); + return; } - /* NOTE: there are no "empty" headers so - * if the pointer `p' is not NULL we must - * assume that we reached the end of the - * buffer before we hit the end of the header. - */ - - if (p) + /* Convert iob into something sed() can digest */ + if (JB_ERR_PARSE == get_server_headers(csp)) { if (ms_iis5_hack) { @@ -1698,6 +2320,17 @@ static void chat(struct client_state *csp) } } + /* Did we actually get anything? */ + if (NULL == csp->headers->first) + { + log_error(LOG_LEVEL_ERROR, "Empty server or forwarder response."); + log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" 502 0", csp->ip_addr_str, http->cmd); + strcpy(buf, NO_SERVER_DATA_RESPONSE); + write_socket(csp->cfd, buf, strlen(buf)); + free_http_request(http); + return; + } + /* we have now received the entire header. * filter it and send the result to the client */ @@ -1776,7 +2409,7 @@ static void chat(struct client_state *csp) return; } - byte_count += len; + byte_count += (size_t)len; } /* we're finished with the server's header */ @@ -1800,8 +2433,18 @@ static void chat(struct client_state *csp) return; /* huh? we should never get here */ } + if (csp->content_length == 0) + { + /* + * If Privoxy didn't recalculate the + * Content-Lenght, byte_count is still + * correct. + */ + csp->content_length = byte_count; + } + log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" 200 %d", - csp->ip_addr_str, http->ocmd, byte_count); + csp->ip_addr_str, http->ocmd, csp->content_length); } @@ -1885,6 +2528,73 @@ void usage(const char *myname) } +/********************************************************************* + * + * Function : initialize_mutexes + * + * Description : Prepares mutexes if mutex support is available. + * + * Parameters : None + * + * Returns : Void, exits in case of errors. + * + *********************************************************************/ +void initialize_mutexes() +{ + int err = 0; + +#ifdef FEATURE_PTHREAD + /* + * Prepare global mutex semaphores + */ + err = pthread_mutex_init(&log_mutex, 0); + + if (!err) err = pthread_mutex_init(&log_init_mutex, 0); + + /* + * XXX: The assumptions below are a bit naive + * and can cause locks that aren't necessary. + * + * For example older FreeBSD versions (< 6.x?) + * have no gethostbyname_r, but gethostbyname is + * thead safe. + */ +#ifndef HAVE_GMTIME_R + if (!err) err = pthread_mutex_init(&gmtime_mutex, 0); +#endif /* ndef HAVE_GMTIME_R */ + +#ifndef HAVE_LOCALTIME_R + if (!err) err = pthread_mutex_init(&localtime_mutex, 0); +#endif /* ndef HAVE_GMTIME_R */ + +#ifndef HAVE_GETHOSTBYADDR_R + if (!err) err = pthread_mutex_init(&gethostbyaddr_mutex, 0); +#endif /* ndef HAVE_GETHOSTBYADDR_R */ + +#ifndef HAVE_GETHOSTBYNAME_R + if (!err) err = pthread_mutex_init(&gethostbyname_mutex, 0); +#endif /* ndef HAVE_GETHOSTBYNAME_R */ + +#ifndef HAVE_RANDOM + if (!err) err = pthread_mutex_init(&rand_mutex, 0); +#endif /* ndef HAVE_RANDOM */ +#endif /* FEATURE_PTHREAD */ + + /* + * TODO: mutex support for mingw32 would be swell. + */ + + if (err) + { + printf("Fatal error. Mutex initialization failed: %s.\n", + strerror(err)); + exit(1); + } + + return; +} + + /********************************************************************* * * Function : main @@ -1915,9 +2625,7 @@ int main(int argc, const char *argv[]) #endif { int argc_pos = 0; -#ifdef HAVE_RANDOM unsigned int random_seed; -#endif /* ifdef HAVE_RANDOM */ #ifdef unix struct passwd *pw = NULL; struct group *grp = NULL; @@ -1982,7 +2690,7 @@ int main(int argc, const char *argv[]) #if defined(unix) - else if (strcmp(argv[argc_pos], "--no-daemon" ) == 0) + else if (strcmp(argv[argc_pos], "--no-daemon" ) == 0) { no_daemon = 1; } @@ -2062,26 +2770,14 @@ int main(int argc, const char *argv[]) InitWin32(); #endif -#if defined(OSX_DARWIN) || defined(__OpenBSD__) - /* - * Prepare global mutex semaphores - */ -#ifdef OSX_DARWIN - pthread_mutex_init(&gmtime_mutex,0); - pthread_mutex_init(&localtime_mutex,0); -#endif /* def OSX_DARWIN */ - pthread_mutex_init(&gethostbyaddr_mutex,0); - pthread_mutex_init(&gethostbyname_mutex,0); -#endif /* defined(OSX_DARWIN) || defined(__OpenBSD__) */ + /* Prepare mutexes if supported and necessary. */ + initialize_mutexes(); -#ifdef FEATURE_PTHREAD - pthread_mutex_init(&log_mutex,0); - pthread_mutex_init(&log_init_mutex,0); -#endif /* FEATURE_PTHREAD */ - -#ifdef HAVE_RANDOM random_seed = (unsigned int)time(NULL); +#ifdef HAVE_RANDOM srandom(random_seed); +#else + srand(random_seed); #endif /* ifdef HAVE_RANDOM */ /* @@ -2094,12 +2790,16 @@ int main(int argc, const char *argv[]) #if !defined(_WIN32) && !defined(__OS2__) && !defined(AMIGA) { int idx; - const int catched_signals[] = { SIGABRT, SIGTERM, SIGINT, SIGHUP, 0 }; + const int catched_signals[] = { SIGTERM, SIGINT, SIGHUP, 0 }; const int ignored_signals[] = { SIGPIPE, 0 }; for (idx = 0; catched_signals[idx] != 0; idx++) { +#ifdef sun /* FIXME: Is it safe to check for HAVE_SIGSET instead? */ + if (sigset(catched_signals[idx], sig_handler) == SIG_ERR) +#else if (signal(catched_signals[idx], sig_handler) == SIG_ERR) +#endif /* ifdef sun */ { log_error(LOG_LEVEL_FATAL, "Can't set signal-handler for signal %d: %E", catched_signals[idx]); } @@ -2120,7 +2820,7 @@ int main(int argc, const char *argv[]) * We *are* in a windows console app. * Print a verbose messages about FAQ's and such */ - printf(win32_blurb); + printf("%s", win32_blurb); # endif /* def _WIN_CONSOLE */ #endif /* def _WIN32 */ @@ -2200,7 +2900,7 @@ int main(int argc, const char *argv[]) * to the user and group ID indicated by the --user option */ write_pid_file(); - + if (NULL != pw) { if (setgid((NULL != grp) ? grp->gr_gid : pw->pw_gid)) @@ -2470,7 +3170,7 @@ static void listen_loop(void) bfd = bind_port_helper(config); } - log_error(LOG_LEVEL_CONNECT, "accept connection ... "); + log_error(LOG_LEVEL_CONNECT, "Listening for new connections ... "); if (!accept_connection(csp, bfd)) { @@ -2487,7 +3187,7 @@ static void listen_loop(void) } else { - log_error(LOG_LEVEL_CONNECT, "OK"); + log_error(LOG_LEVEL_CONNECT, "accepted connection from %s", csp->ip_addr_str); } #ifdef FEATURE_TOGGLE @@ -2506,7 +3206,7 @@ static void listen_loop(void) #ifdef FEATURE_ACL if (block_acl(NULL,csp)) { - log_error(LOG_LEVEL_CONNECT, "Connection dropped due to ACL"); + log_error(LOG_LEVEL_CONNECT, "Connection from %s dropped due to ACL", csp->ip_addr_str); close_socket(csp->cfd); freez(csp); continue; @@ -2534,7 +3234,7 @@ static void listen_loop(void) pthread_attr_init(&attrs); pthread_attr_setdetachstate(&attrs, PTHREAD_CREATE_DETACHED); errno = pthread_create(&the_thread, &attrs, - (void*)serve, csp); + (void * (*)(void *))serve, csp); child_id = errno ? -1 : 0; pthread_attr_destroy(&attrs); } @@ -2578,13 +3278,22 @@ static void listen_loop(void) #define SELECTED_ONE_OPTION csp->cfd = ReleaseSocket(csp->cfd, -1); - if((child_id = (int)CreateNewProcTags( - NP_Entry, (ULONG)server_thread, - NP_Output, Output(), - NP_CloseOutput, FALSE, - NP_Name, (ULONG)"privoxy child", - NP_StackSize, 200*1024, - TAG_DONE))) +#ifdef __amigaos4__ + child_id = (int)CreateNewProcTags(NP_Entry, (ULONG)server_thread, + NP_Output, Output(), + NP_CloseOutput, FALSE, + NP_Name, (ULONG)"privoxy child", + NP_Child, TRUE, + TAG_DONE); +#else + child_id = (int)CreateNewProcTags(NP_Entry, (ULONG)server_thread, + NP_Output, Output(), + NP_CloseOutput, FALSE, + NP_Name, (ULONG)"privoxy child", + NP_StackSize, 200*1024, + TAG_DONE); +#endif + if(0 != child_id) { childs++; ((struct Task *)child_id)->tc_UserData = csp; @@ -2676,7 +3385,7 @@ static void listen_loop(void) log_error(LOG_LEVEL_ERROR, "can't fork: %E"); - sprintf(buf , "Privoxy: can't fork: errno = %d", errno); + snprintf(buf , sizeof(buf), "Privoxy: can't fork: errno = %d", errno); write_socket(csp->cfd, buf, strlen(buf)); close_socket(csp->cfd);