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- /*********************************************************************
- *
- * File : $Source: /cvsroot/ijbswa/current/filters.c,v $
- *
- * Purpose : Declares functions to parse/crunch headers and pages.
- *
- * Copyright : Written by and Copyright (C) 2001-2020 the
- * Privoxy team. https://www.privoxy.org/
- *
- * Based on the Internet Junkbuster originally written
- * by and Copyright (C) 1997 Anonymous Coders and
- * Junkbusters Corporation. http://www.junkbusters.com
- *
- * This program is free software; you can redistribute it
- * and/or modify it under the terms of the GNU General
- * Public License as published by the Free Software
- * Foundation; either version 2 of the License, or (at
- * your option) any later version.
- *
- * This program is distributed in the hope that it will
- * be useful, but WITHOUT ANY WARRANTY; without even the
- * implied warranty of MERCHANTABILITY or FITNESS FOR A
- * PARTICULAR PURPOSE. See the GNU General Public
- * License for more details.
- *
- * The GNU General Public License should be included with
- * this file. If not, you can view it at
- * http://www.gnu.org/copyleft/gpl.html
- * or write to the Free Software Foundation, Inc., 59
- * Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- *
- *********************************************************************/
- #include "config.h"
- #include <stdio.h>
- #include <sys/types.h>
- #include <stdlib.h>
- #include <ctype.h>
- #include <string.h>
- #include <assert.h>
- #ifndef _WIN32
- #include <unistd.h>
- #include <netinet/in.h>
- #else
- #include <winsock2.h>
- #endif /* ndef _WIN32 */
- #include "project.h"
- #include "filters.h"
- #include "encode.h"
- #include "parsers.h"
- #include "ssplit.h"
- #include "errlog.h"
- #include "jbsockets.h"
- #include "miscutil.h"
- #include "actions.h"
- #include "cgi.h"
- #include "jcc.h"
- #include "list.h"
- #include "deanimate.h"
- #include "urlmatch.h"
- #include "loaders.h"
- #ifdef FEATURE_CLIENT_TAGS
- #include "client-tags.h"
- #endif
- #ifdef _WIN32
- #include "win32.h"
- #endif
- typedef char *(*filter_function_ptr)();
- static filter_function_ptr get_filter_function(const struct client_state *csp);
- static jb_err prepare_for_filtering(struct client_state *csp);
- static void apply_url_actions(struct current_action_spec *action,
- struct http_request *http,
- #ifdef FEATURE_CLIENT_TAGS
- const struct list *client_tags,
- #endif
- struct url_actions *b);
- #ifdef FEATURE_EXTENDED_STATISTICS
- static void increment_block_reason_counter(const char *block_reason);
- #endif
- #ifdef FEATURE_ACL
- #ifdef HAVE_RFC2553
- /*********************************************************************
- *
- * Function : sockaddr_storage_to_ip
- *
- * Description : Access internal structure of sockaddr_storage
- *
- * Parameters :
- * 1 : addr = socket address
- * 2 : ip = IP address as array of octets in network order
- * (it points into addr)
- * 3 : len = length of IP address in octets
- * 4 : port = port number in network order;
- *
- * Returns : void
- *
- *********************************************************************/
- static void sockaddr_storage_to_ip(const struct sockaddr_storage *addr,
- uint8_t **ip, unsigned int *len,
- in_port_t **port)
- {
- assert(NULL != addr);
- assert(addr->ss_family == AF_INET || addr->ss_family == AF_INET6);
- switch (addr->ss_family)
- {
- case AF_INET:
- if (NULL != len)
- {
- *len = 4;
- }
- if (NULL != ip)
- {
- *ip = (uint8_t *)
- &(((struct sockaddr_in *)addr)->sin_addr.s_addr);
- }
- if (NULL != port)
- {
- *port = &((struct sockaddr_in *)addr)->sin_port;
- }
- break;
- case AF_INET6:
- if (NULL != len)
- {
- *len = 16;
- }
- if (NULL != ip)
- {
- *ip = ((struct sockaddr_in6 *)addr)->sin6_addr.s6_addr;
- }
- if (NULL != port)
- {
- *port = &((struct sockaddr_in6 *)addr)->sin6_port;
- }
- break;
- }
- }
- /*********************************************************************
- *
- * Function : match_sockaddr
- *
- * Description : Check whether address matches network (IP address and port)
- *
- * Parameters :
- * 1 : network = socket address of subnework
- * 2 : netmask = network mask as socket address
- * 3 : address = checked socket address against given network
- *
- * Returns : 0 = doesn't match; 1 = does match
- *
- *********************************************************************/
- static int match_sockaddr(const struct sockaddr_storage *network,
- const struct sockaddr_storage *netmask,
- const struct sockaddr_storage *address)
- {
- uint8_t *network_addr, *netmask_addr, *address_addr;
- unsigned int addr_len;
- in_port_t *network_port, *netmask_port, *address_port;
- int i;
- if (network->ss_family != netmask->ss_family)
- {
- /* This should never happen */
- assert(network->ss_family == netmask->ss_family);
- log_error(LOG_LEVEL_FATAL, "Network and netmask differ in family.");
- }
- sockaddr_storage_to_ip(network, &network_addr, &addr_len, &network_port);
- sockaddr_storage_to_ip(netmask, &netmask_addr, NULL, &netmask_port);
- sockaddr_storage_to_ip(address, &address_addr, NULL, &address_port);
- /* Check for family */
- if ((network->ss_family == AF_INET) && (address->ss_family == AF_INET6)
- && IN6_IS_ADDR_V4MAPPED((struct in6_addr *)address_addr))
- {
- /* Map AF_INET6 V4MAPPED address into AF_INET */
- address_addr += 12;
- addr_len = 4;
- }
- else if ((network->ss_family == AF_INET6) && (address->ss_family == AF_INET)
- && IN6_IS_ADDR_V4MAPPED((struct in6_addr *)network_addr))
- {
- /* Map AF_INET6 V4MAPPED network into AF_INET */
- network_addr += 12;
- netmask_addr += 12;
- addr_len = 4;
- }
- /* XXX: Port check is signaled in netmask */
- if (*netmask_port && *network_port != *address_port)
- {
- return 0;
- }
- /* TODO: Optimize by checking by words instead of octets */
- for (i = 0; (i < addr_len) && netmask_addr[i]; i++)
- {
- if ((network_addr[i] & netmask_addr[i]) !=
- (address_addr[i] & netmask_addr[i]))
- {
- return 0;
- }
- }
- return 1;
- }
- #endif /* def HAVE_RFC2553 */
- /*********************************************************************
- *
- * Function : block_acl
- *
- * Description : Block this request?
- * Decide yes or no based on ACL file.
- *
- * Parameters :
- * 1 : dst = The proxy or gateway address this is going to.
- * Or NULL to check all possible targets.
- * 2 : csp = Current client state (buffers, headers, etc...)
- * Also includes the client IP address.
- *
- * Returns : 0 = FALSE (don't block) and 1 = TRUE (do block)
- *
- *********************************************************************/
- int block_acl(const struct access_control_addr *dst, const struct client_state *csp)
- {
- struct access_control_list *acl = csp->config->acl;
- /* if not using an access control list, then permit the connection */
- if (acl == NULL)
- {
- return(0);
- }
- /* search the list */
- while (acl != NULL)
- {
- if (
- #ifdef HAVE_RFC2553
- match_sockaddr(&acl->src->addr, &acl->src->mask, &csp->tcp_addr)
- #else
- (csp->ip_addr_long & acl->src->mask) == acl->src->addr
- #endif
- )
- {
- if (dst == NULL)
- {
- /* Just want to check if they have any access */
- if (acl->action == ACL_PERMIT)
- {
- return(0);
- }
- else
- {
- return(1);
- }
- }
- else if (
- #ifdef HAVE_RFC2553
- /*
- * XXX: An undefined acl->dst is full of zeros and should be
- * considered a wildcard address. sockaddr_storage_to_ip()
- * fails on such destinations because of unknown sa_familly
- * (glibc only?). However this test is not portable.
- *
- * So, we signal the acl->dst is wildcard in wildcard_dst.
- */
- acl->wildcard_dst ||
- match_sockaddr(&acl->dst->addr, &acl->dst->mask, &dst->addr)
- #else
- ((dst->addr & acl->dst->mask) == acl->dst->addr)
- && ((dst->port == acl->dst->port) || (acl->dst->port == 0))
- #endif
- )
- {
- if (acl->action == ACL_PERMIT)
- {
- return(0);
- }
- else
- {
- return(1);
- }
- }
- }
- acl = acl->next;
- }
- return(1);
- }
- /*********************************************************************
- *
- * Function : acl_addr
- *
- * Description : Called from `load_config' to parse an ACL address.
- *
- * Parameters :
- * 1 : aspec = String specifying ACL address.
- * 2 : aca = struct access_control_addr to fill in.
- *
- * Returns : 0 => Ok, everything else is an error.
- *
- *********************************************************************/
- int acl_addr(const char *aspec, struct access_control_addr *aca)
- {
- int i, masklength;
- #ifdef HAVE_RFC2553
- struct addrinfo hints, *result;
- uint8_t *mask_data;
- in_port_t *mask_port;
- unsigned int addr_len;
- #else
- long port;
- #endif /* def HAVE_RFC2553 */
- char *p;
- char *acl_spec = NULL;
- #ifdef HAVE_RFC2553
- /* XXX: Depend on ai_family */
- masklength = 128;
- #else
- masklength = 32;
- port = 0;
- #endif
- /*
- * Use a temporary acl spec copy so we can log
- * the unmodified original in case of parse errors.
- */
- acl_spec = strdup_or_die(aspec);
- if ((p = strchr(acl_spec, '/')) != NULL)
- {
- *p++ = '\0';
- if (privoxy_isdigit(*p) == 0)
- {
- freez(acl_spec);
- return(-1);
- }
- masklength = atoi(p);
- }
- if ((masklength < 0) ||
- #ifdef HAVE_RFC2553
- (masklength > 128)
- #else
- (masklength > 32)
- #endif
- )
- {
- freez(acl_spec);
- return(-1);
- }
- if ((*acl_spec == '[') && (NULL != (p = strchr(acl_spec, ']'))))
- {
- *p = '\0';
- memmove(acl_spec, acl_spec + 1, (size_t)(p - acl_spec));
- if (*++p != ':')
- {
- p = NULL;
- }
- }
- else
- {
- p = strchr(acl_spec, ':');
- }
- if (p != NULL)
- {
- assert(*p == ':');
- *p = '\0';
- p++;
- }
- #ifdef HAVE_RFC2553
- memset(&hints, 0, sizeof(struct addrinfo));
- hints.ai_family = AF_UNSPEC;
- hints.ai_socktype = SOCK_STREAM;
- i = getaddrinfo(acl_spec, p, &hints, &result);
- if (i != 0)
- {
- log_error(LOG_LEVEL_ERROR, "Can not resolve [%s]:%s: %s",
- acl_spec, p, gai_strerror(i));
- freez(acl_spec);
- return(-1);
- }
- freez(acl_spec);
- /* TODO: Allow multihomed hostnames */
- memcpy(&(aca->addr), result->ai_addr, result->ai_addrlen);
- freeaddrinfo(result);
- #else
- if (p != NULL)
- {
- char *endptr;
- port = strtol(p, &endptr, 10);
- if (port <= 0 || port > 65535 || *endptr != '\0')
- {
- freez(acl_spec);
- return(-1);
- }
- }
- aca->port = (unsigned long)port;
- aca->addr = ntohl(resolve_hostname_to_ip(acl_spec));
- freez(acl_spec);
- if (aca->addr == INADDR_NONE)
- {
- /* XXX: This will be logged as parse error. */
- return(-1);
- }
- #endif /* def HAVE_RFC2553 */
- /* build the netmask */
- #ifdef HAVE_RFC2553
- /* Clip masklength according to current family. */
- if ((aca->addr.ss_family == AF_INET) && (masklength > 32))
- {
- masklength = 32;
- }
- aca->mask.ss_family = aca->addr.ss_family;
- sockaddr_storage_to_ip(&aca->mask, &mask_data, &addr_len, &mask_port);
- if (p)
- {
- /* ACL contains a port number, check ports in the future. */
- *mask_port = 1;
- }
- /*
- * XXX: This could be optimized to operate on whole words instead
- * of octets (128-bit CPU could do it in one iteration).
- */
- /*
- * Octets after prefix can be omitted because of
- * previous initialization to zeros.
- */
- for (i = 0; (i < addr_len) && masklength; i++)
- {
- if (masklength >= 8)
- {
- mask_data[i] = 0xFF;
- masklength -= 8;
- }
- else
- {
- /*
- * XXX: This assumes MSB of octet is on the left side.
- * This should be true for all architectures or solved
- * by the link layer.
- */
- mask_data[i] = (uint8_t)~((1 << (8 - masklength)) - 1);
- masklength = 0;
- }
- }
- #else
- aca->mask = 0;
- for (i=1; i <= masklength ; i++)
- {
- aca->mask |= (1U << (32 - i));
- }
- /* now mask off the host portion of the ip address
- * (i.e. save on the network portion of the address).
- */
- aca->addr = aca->addr & aca->mask;
- #endif /* def HAVE_RFC2553 */
- return(0);
- }
- #endif /* def FEATURE_ACL */
- /*********************************************************************
- *
- * Function : connect_port_is_forbidden
- *
- * Description : Check to see if CONNECT requests to the destination
- * port of this request are forbidden. The check is
- * independent of the actual request method.
- *
- * Parameters :
- * 1 : csp = Current client state (buffers, headers, etc...)
- *
- * Returns : True if yes, false otherwise.
- *
- *********************************************************************/
- int connect_port_is_forbidden(const struct client_state *csp)
- {
- return ((csp->action->flags & ACTION_LIMIT_CONNECT) &&
- !match_portlist(csp->action->string[ACTION_STRING_LIMIT_CONNECT],
- csp->http->port));
- }
- /*********************************************************************
- *
- * Function : block_url
- *
- * Description : Called from `chat'. Check to see if we need to block this.
- *
- * Parameters :
- * 1 : csp = Current client state (buffers, headers, etc...)
- *
- * Returns : NULL => unblocked, else HTTP block response
- *
- *********************************************************************/
- struct http_response *block_url(struct client_state *csp)
- {
- struct http_response *rsp;
- const char *new_content_type = NULL;
- /*
- * If it's not blocked, don't block it ;-)
- */
- if ((csp->action->flags & ACTION_BLOCK) == 0)
- {
- return NULL;
- }
- if (csp->action->flags & ACTION_REDIRECT)
- {
- log_error(LOG_LEVEL_ERROR, "redirect{} overruled by block.");
- }
- /*
- * Else, prepare a response
- */
- if (NULL == (rsp = alloc_http_response()))
- {
- return cgi_error_memory();
- }
- #ifdef FEATURE_EXTENDED_STATISTICS
- if (csp->action->string[ACTION_STRING_BLOCK] != NULL)
- {
- increment_block_reason_counter(csp->action->string[ACTION_STRING_BLOCK]);
- }
- #endif
- /*
- * If it's an image-url, send back an image or redirect
- * as specified by the relevant +image action
- */
- #ifdef FEATURE_IMAGE_BLOCKING
- if (((csp->action->flags & ACTION_IMAGE_BLOCKER) != 0)
- && is_imageurl(csp))
- {
- char *p;
- /* determine HOW images should be blocked */
- p = csp->action->string[ACTION_STRING_IMAGE_BLOCKER];
- if (csp->action->flags & ACTION_HANDLE_AS_EMPTY_DOCUMENT)
- {
- log_error(LOG_LEVEL_ERROR, "handle-as-empty-document overruled by handle-as-image.");
- }
- /* and handle accordingly: */
- if ((p == NULL) || (0 == strcmpic(p, "pattern")))
- {
- rsp->status = strdup_or_die("403 Request blocked by Privoxy");
- rsp->body = bindup(image_pattern_data, image_pattern_length);
- if (rsp->body == NULL)
- {
- free_http_response(rsp);
- return cgi_error_memory();
- }
- rsp->content_length = image_pattern_length;
- if (enlist_unique_header(rsp->headers, "Content-Type", BUILTIN_IMAGE_MIMETYPE))
- {
- free_http_response(rsp);
- return cgi_error_memory();
- }
- }
- else if (0 == strcmpic(p, "blank"))
- {
- rsp->status = strdup_or_die("403 Request blocked by Privoxy");
- rsp->body = bindup(image_blank_data, image_blank_length);
- if (rsp->body == NULL)
- {
- free_http_response(rsp);
- return cgi_error_memory();
- }
- rsp->content_length = image_blank_length;
- if (enlist_unique_header(rsp->headers, "Content-Type", BUILTIN_IMAGE_MIMETYPE))
- {
- free_http_response(rsp);
- return cgi_error_memory();
- }
- }
- else
- {
- rsp->status = strdup_or_die("302 Local Redirect from Privoxy");
- if (enlist_unique_header(rsp->headers, "Location", p))
- {
- free_http_response(rsp);
- return cgi_error_memory();
- }
- }
- }
- else
- #endif /* def FEATURE_IMAGE_BLOCKING */
- if (csp->action->flags & ACTION_HANDLE_AS_EMPTY_DOCUMENT)
- {
- /*
- * Send empty document.
- */
- new_content_type = csp->action->string[ACTION_STRING_CONTENT_TYPE];
- freez(rsp->body);
- rsp->body = strdup_or_die(" ");
- rsp->content_length = 1;
- if (csp->config->feature_flags & RUNTIME_FEATURE_EMPTY_DOC_RETURNS_OK)
- {
- /*
- * Workaround for firefox bug 492459
- * https://bugzilla.mozilla.org/show_bug.cgi?id=492459
- * Return a 200 OK status for pages blocked with +handle-as-empty-document
- * if the "handle-as-empty-doc-returns-ok" runtime config option is set.
- */
- rsp->status = strdup_or_die("200 Request blocked by Privoxy");
- }
- else
- {
- rsp->status = strdup_or_die("403 Request blocked by Privoxy");
- }
- if (new_content_type != 0)
- {
- log_error(LOG_LEVEL_HEADER, "Overwriting Content-Type with %s", new_content_type);
- if (enlist_unique_header(rsp->headers, "Content-Type", new_content_type))
- {
- free_http_response(rsp);
- return cgi_error_memory();
- }
- }
- }
- else
- /*
- * Else, generate an HTML "blocked" message:
- */
- {
- jb_err err;
- struct map * exports;
- rsp->status = strdup_or_die("403 Request blocked by Privoxy");
- exports = default_exports(csp, NULL);
- if (exports == NULL)
- {
- free_http_response(rsp);
- return cgi_error_memory();
- }
- #ifdef FEATURE_FORCE_LOAD
- err = map(exports, "force-prefix", 1, FORCE_PREFIX, 1);
- /*
- * Export the force conditional block killer if
- *
- * - Privoxy was compiled without FEATURE_FORCE_LOAD, or
- * - Privoxy is configured to enforce blocks, or
- * - it's a CONNECT request and enforcing wouldn't work anyway.
- */
- if ((csp->config->feature_flags & RUNTIME_FEATURE_ENFORCE_BLOCKS)
- || (0 == strcmpic(csp->http->gpc, "connect")))
- #endif /* ndef FEATURE_FORCE_LOAD */
- {
- err = map_block_killer(exports, "force-support");
- }
- if (!err) err = map(exports, "protocol", 1, csp->http->ssl ? "https://" : "http://", 1);
- if (!err) err = map(exports, "hostport", 1, html_encode(csp->http->hostport), 0);
- if (!err) err = map(exports, "path", 1, html_encode(csp->http->path), 0);
- if (!err) err = map(exports, "path-ue", 1, url_encode(csp->http->path), 0);
- if (!err)
- {
- const char *block_reason;
- if (csp->action->string[ACTION_STRING_BLOCK] != NULL)
- {
- block_reason = csp->action->string[ACTION_STRING_BLOCK];
- }
- else
- {
- assert(connect_port_is_forbidden(csp));
- block_reason = "Forbidden CONNECT port.";
- }
- err = map(exports, "block-reason", 1, html_encode(block_reason), 0);
- }
- if (err)
- {
- free_map(exports);
- free_http_response(rsp);
- return cgi_error_memory();
- }
- err = template_fill_for_cgi(csp, "blocked", exports, rsp);
- if (err)
- {
- free_http_response(rsp);
- return cgi_error_memory();
- }
- }
- rsp->crunch_reason = BLOCKED;
- return finish_http_response(csp, rsp);
- }
- #ifdef FEATURE_TRUST
- /*********************************************************************
- *
- * Function : trust_url FIXME: I should be called distrust_url
- *
- * Description : Calls is_untrusted_url to determine if the URL is trusted
- * and if not, returns a HTTP 403 response with a reject message.
- *
- * Parameters :
- * 1 : csp = Current client state (buffers, headers, etc...)
- *
- * Returns : NULL => trusted, else http_response.
- *
- *********************************************************************/
- struct http_response *trust_url(struct client_state *csp)
- {
- struct http_response *rsp;
- struct map * exports;
- char buf[BUFFER_SIZE];
- char *p;
- struct pattern_spec **tl;
- struct pattern_spec *t;
- jb_err err;
- /*
- * Don't bother to work on trusted URLs
- */
- if (!is_untrusted_url(csp))
- {
- return NULL;
- }
- /*
- * Else, prepare a response:
- */
- if (NULL == (rsp = alloc_http_response()))
- {
- return cgi_error_memory();
- }
- rsp->status = strdup_or_die("403 Request blocked by Privoxy");
- exports = default_exports(csp, NULL);
- if (exports == NULL)
- {
- free_http_response(rsp);
- return cgi_error_memory();
- }
- /*
- * Export the protocol, host, port, and referrer information
- */
- err = map(exports, "hostport", 1, csp->http->hostport, 1);
- if (!err) err = map(exports, "protocol", 1, csp->http->ssl ? "https://" : "http://", 1);
- if (!err) err = map(exports, "path", 1, csp->http->path, 1);
- if (NULL != (p = get_header_value(csp->headers, "Referer:")))
- {
- if (!err) err = map(exports, "referrer", 1, html_encode(p), 0);
- }
- else
- {
- if (!err) err = map(exports, "referrer", 1, "none set", 1);
- }
- if (err)
- {
- free_map(exports);
- free_http_response(rsp);
- return cgi_error_memory();
- }
- /*
- * Export the trust list
- */
- p = strdup_or_die("");
- for (tl = csp->config->trust_list; (t = *tl) != NULL ; tl++)
- {
- snprintf(buf, sizeof(buf), "<li>%s</li>\n", t->spec);
- string_append(&p, buf);
- }
- err = map(exports, "trusted-referrers", 1, p, 0);
- if (err)
- {
- free_map(exports);
- free_http_response(rsp);
- return cgi_error_memory();
- }
- /*
- * Export the trust info, if available
- */
- if (csp->config->trust_info->first)
- {
- struct list_entry *l;
- p = strdup_or_die("");
- for (l = csp->config->trust_info->first; l ; l = l->next)
- {
- snprintf(buf, sizeof(buf), "<li> <a href=\"%s\">%s</a><br>\n", l->str, l->str);
- string_append(&p, buf);
- }
- err = map(exports, "trust-info", 1, p, 0);
- }
- else
- {
- err = map_block_killer(exports, "have-trust-info");
- }
- if (err)
- {
- free_map(exports);
- free_http_response(rsp);
- return cgi_error_memory();
- }
- /*
- * Export the force conditional block killer if
- *
- * - Privoxy was compiled without FEATURE_FORCE_LOAD, or
- * - Privoxy is configured to enforce blocks, or
- * - it's a CONNECT request and enforcing wouldn't work anyway.
- */
- #ifdef FEATURE_FORCE_LOAD
- if ((csp->config->feature_flags & RUNTIME_FEATURE_ENFORCE_BLOCKS)
- || (0 == strcmpic(csp->http->gpc, "connect")))
- {
- err = map_block_killer(exports, "force-support");
- }
- else
- {
- err = map(exports, "force-prefix", 1, FORCE_PREFIX, 1);
- }
- #else /* ifndef FEATURE_FORCE_LOAD */
- err = map_block_killer(exports, "force-support");
- #endif /* ndef FEATURE_FORCE_LOAD */
- if (err)
- {
- free_map(exports);
- free_http_response(rsp);
- return cgi_error_memory();
- }
- /*
- * Build the response
- */
- err = template_fill_for_cgi(csp, "untrusted", exports, rsp);
- if (err)
- {
- free_http_response(rsp);
- return cgi_error_memory();
- }
- rsp->crunch_reason = UNTRUSTED;
- return finish_http_response(csp, rsp);
- }
- #endif /* def FEATURE_TRUST */
- /*********************************************************************
- *
- * Function : compile_dynamic_pcrs_job_list
- *
- * Description : Compiles a dynamic pcrs job list (one with variables
- * resolved at request time)
- *
- * Parameters :
- * 1 : csp = Current client state (buffers, headers, etc...)
- * 2 : b = The filter list to compile
- *
- * Returns : NULL in case of errors, otherwise the
- * pcrs job list.
- *
- *********************************************************************/
- pcrs_job *compile_dynamic_pcrs_job_list(const struct client_state *csp, const struct re_filterfile_spec *b)
- {
- struct list_entry *pattern;
- pcrs_job *job_list = NULL;
- pcrs_job *dummy = NULL;
- pcrs_job *lastjob = NULL;
- int error = 0;
- const struct pcrs_variable variables[] =
- {
- {"url", csp->http->url, 1},
- {"path", csp->http->path, 1},
- {"host", csp->http->host, 1},
- {"origin", csp->ip_addr_str, 1},
- {"listen-address", csp->listen_addr_str, 1},
- {NULL, NULL, 1}
- };
- for (pattern = b->patterns->first; pattern != NULL; pattern = pattern->next)
- {
- assert(pattern->str != NULL);
- dummy = pcrs_compile_dynamic_command(pattern->str, variables, &error);
- if (NULL == dummy)
- {
- log_error(LOG_LEVEL_ERROR,
- "Compiling dynamic pcrs job '%s' for '%s' failed with error code %d: %s",
- pattern->str, b->name, error, pcrs_strerror(error));
- continue;
- }
- else
- {
- if (error == PCRS_WARN_TRUNCATION)
- {
- log_error(LOG_LEVEL_ERROR,
- "At least one of the variables in \'%s\' had to "
- "be truncated before compilation", pattern->str);
- }
- if (job_list == NULL)
- {
- job_list = dummy;
- }
- else
- {
- lastjob->next = dummy;
- }
- lastjob = dummy;
- }
- }
- return job_list;
- }
- /*********************************************************************
- *
- * Function : rewrite_url
- *
- * Description : Rewrites a URL with a single pcrs command
- * and returns the result if it differs from the
- * original and isn't obviously invalid.
- *
- * Parameters :
- * 1 : old_url = URL to rewrite.
- * 2 : pcrs_command = pcrs command formatted as string (s@foo@bar@)
- *
- *
- * Returns : NULL if the pcrs_command didn't change the url, or
- * the result of the modification.
- *
- *********************************************************************/
- char *rewrite_url(char *old_url, const char *pcrs_command)
- {
- char *new_url = NULL;
- int hits;
- assert(old_url);
- assert(pcrs_command);
- new_url = pcrs_execute_single_command(old_url, pcrs_command, &hits);
- if (hits == 0)
- {
- log_error(LOG_LEVEL_REDIRECTS,
- "pcrs command \"%s\" didn't change \"%s\".",
- pcrs_command, old_url);
- freez(new_url);
- }
- else if (hits < 0)
- {
- log_error(LOG_LEVEL_REDIRECTS,
- "executing pcrs command \"%s\" to rewrite %s failed: %s",
- pcrs_command, old_url, pcrs_strerror(hits));
- freez(new_url);
- }
- else if (strncmpic(new_url, "http://", 7) && strncmpic(new_url, "https://", 8))
- {
- log_error(LOG_LEVEL_ERROR,
- "pcrs command \"%s\" changed \"%s\" to \"%s\" (%u hi%s), "
- "but the result doesn't look like a valid URL and will be ignored.",
- pcrs_command, old_url, new_url, hits, (hits == 1) ? "t" : "ts");
- freez(new_url);
- }
- else
- {
- log_error(LOG_LEVEL_REDIRECTS,
- "pcrs command \"%s\" changed \"%s\" to \"%s\" (%u hi%s).",
- pcrs_command, old_url, new_url, hits, (hits == 1) ? "t" : "ts");
- }
- return new_url;
- }
- #ifdef FEATURE_FAST_REDIRECTS
- /*********************************************************************
- *
- * Function : get_last_url
- *
- * Description : Search for the last URL inside a string.
- * If the string already is a URL, it will
- * be the first URL found.
- *
- * Parameters :
- * 1 : subject = the string to check
- * 2 : redirect_mode = +fast-redirect{} mode
- *
- * Returns : NULL if no URL was found, or
- * the last URL found.
- *
- *********************************************************************/
- static char *get_last_url(char *subject, const char *redirect_mode)
- {
- char *new_url = NULL;
- char *tmp;
- assert(subject);
- assert(redirect_mode);
- subject = strdup(subject);
- if (subject == NULL)
- {
- log_error(LOG_LEVEL_ERROR, "Out of memory while searching for redirects.");
- return NULL;
- }
- if (0 == strcmpic(redirect_mode, "check-decoded-url") && strchr(subject, '%'))
- {
- char *url_segment = NULL;
- char **url_segments;
- size_t max_segments;
- int segments;
- log_error(LOG_LEVEL_REDIRECTS,
- "Checking \"%s\" for encoded redirects.", subject);
- /*
- * Check each parameter in the URL separately.
- * Sectionize the URL at "?" and "&",
- * go backwards through the segments, URL-decode them
- * and look for a URL in the decoded result.
- * Stop the search after the first match.
- *
- * XXX: This estimate is guaranteed to be high enough as we
- * let ssplit() ignore empty fields, but also a bit wasteful.
- */
- max_segments = strlen(subject) / 2;
- url_segments = malloc(max_segments * sizeof(char *));
- if (NULL == url_segments)
- {
- log_error(LOG_LEVEL_ERROR,
- "Out of memory while decoding URL: %s", subject);
- freez(subject);
- return NULL;
- }
- segments = ssplit(subject, "?&", url_segments, max_segments);
- while (segments-- > 0)
- {
- char *dtoken = url_decode(url_segments[segments]);
- if (NULL == dtoken)
- {
- log_error(LOG_LEVEL_ERROR, "Unable to decode \"%s\".", url_segments[segments]);
- continue;
- }
- url_segment = strstr(dtoken, "http://");
- if (NULL == url_segment)
- {
- url_segment = strstr(dtoken, "https://");
- }
- if (NULL != url_segment)
- {
- url_segment = strdup_or_die(url_segment);
- freez(dtoken);
- break;
- }
- freez(dtoken);
- }
- freez(subject);
- freez(url_segments);
- if (url_segment == NULL)
- {
- return NULL;
- }
- subject = url_segment;
- }
- else
- {
- /* Look for a URL inside this one, without decoding anything. */
- log_error(LOG_LEVEL_REDIRECTS,
- "Checking \"%s\" for unencoded redirects.", subject);
- }
- /*
- * Find the last URL encoded in the request
- */
- tmp = subject;
- while ((tmp = strstr(tmp, "http://")) != NULL)
- {
- new_url = tmp++;
- }
- tmp = (new_url != NULL) ? new_url : subject;
- while ((tmp = strstr(tmp, "https://")) != NULL)
- {
- new_url = tmp++;
- }
- if ((new_url != NULL)
- && ( (new_url != subject)
- || (0 == strncmpic(subject, "http://", 7))
- || (0 == strncmpic(subject, "https://", 8))
- ))
- {
- /*
- * Return new URL if we found a redirect
- * or if the subject already was a URL.
- *
- * The second case makes sure that we can
- * chain get_last_url after another redirection check
- * (like rewrite_url) without losing earlier redirects.
- */
- new_url = strdup(new_url);
- freez(subject);
- return new_url;
- }
- freez(subject);
- return NULL;
- }
- #endif /* def FEATURE_FAST_REDIRECTS */
- /*********************************************************************
- *
- * Function : redirect_url
- *
- * Description : Checks if Privoxy should answer the request with
- * a HTTP redirect and generates the redirect if
- * necessary.
- *
- * Parameters :
- * 1 : csp = Current client state (buffers, headers, etc...)
- *
- * Returns : NULL if the request can pass, HTTP redirect otherwise.
- *
- *********************************************************************/
- struct http_response *redirect_url(struct client_state *csp)
- {
- struct http_response *rsp;
- #ifdef FEATURE_FAST_REDIRECTS
- /*
- * XXX: Do we still need FEATURE_FAST_REDIRECTS
- * as compile-time option? The user can easily disable
- * it in his action file.
- */
- char * redirect_mode;
- #endif /* def FEATURE_FAST_REDIRECTS */
- char *old_url = NULL;
- char *new_url = NULL;
- char *redirection_string;
- if ((csp->action->flags & ACTION_REDIRECT))
- {
- redirection_string = csp->action->string[ACTION_STRING_REDIRECT];
- /*
- * If the redirection string begins with 's',
- * assume it's a pcrs command, otherwise treat it as
- * properly formatted URL and use it for the redirection
- * directly.
- *
- * According to (the now obsolete) RFC 2616 section 14.30
- * the URL has to be absolute and if the user tries:
- * +redirect{sadly/this/will/be/parsed/as/pcrs_command.html}
- * she would get undefined results anyway.
- *
- * RFC 7231 7.1.2 actually allows relative references,
- * but those start with a leading slash (RFC 3986 4.2) and
- * thus can't be mistaken for pcrs commands either.
- */
- if (*redirection_string == 's')
- {
- old_url = csp->http->url;
- new_url = rewrite_url(old_url, redirection_string);
- }
- else
- {
- log_error(LOG_LEVEL_REDIRECTS,
- "No pcrs command recognized, assuming that \"%s\" is already properly formatted.",
- redirection_string);
- new_url = strdup(redirection_string);
- }
- }
- #ifdef FEATURE_FAST_REDIRECTS
- if ((csp->action->flags & ACTION_FAST_REDIRECTS))
- {
- redirect_mode = csp->action->string[ACTION_STRING_FAST_REDIRECTS];
- /*
- * If it exists, use the previously rewritten URL as input
- * otherwise just use the old path.
- */
- old_url = (new_url != NULL) ? new_url : strdup(csp->http->path);
- new_url = get_last_url(old_url, redirect_mode);
- freez(old_url);
- }
- /*
- * Disable redirect checkers, so that they
- * will be only run more than once if the user
- * also enables them through tags.
- *
- * From a performance point of view
- * it doesn't matter, but the duplicated
- * log messages are annoying.
- */
- csp->action->flags &= ~ACTION_FAST_REDIRECTS;
- #endif /* def FEATURE_FAST_REDIRECTS */
- csp->action->flags &= ~ACTION_REDIRECT;
- /* Did any redirect action trigger? */
- if (new_url)
- {
- if (url_requires_percent_encoding(new_url))
- {
- char *encoded_url;
- log_error(LOG_LEVEL_REDIRECTS, "Percent-encoding redirect URL: %N",
- strlen(new_url), new_url);
- encoded_url = percent_encode_url(new_url);
- freez(new_url);
- if (encoded_url == NULL)
- {
- return cgi_error_memory();
- }
- new_url = encoded_url;
- assert(FALSE == url_requires_percent_encoding(new_url));
- }
- if (0 == strcmpic(new_url, csp->http->url))
- {
- log_error(LOG_LEVEL_ERROR,
- "New URL \"%s\" and old URL \"%s\" are the same. Redirection loop prevented.",
- csp->http->url, new_url);
- freez(new_url);
- }
- else
- {
- log_error(LOG_LEVEL_REDIRECTS, "New URL is: %s", new_url);
- if (NULL == (rsp = alloc_http_response()))
- {
- freez(new_url);
- return cgi_error_memory();
- }
- rsp->status = strdup_or_die("302 Local Redirect from Privoxy");
- if (enlist_unique_header(rsp->headers, "Location", new_url))
- {
- freez(new_url);
- free_http_response(rsp);
- return cgi_error_memory();
- }
- rsp->crunch_reason = REDIRECTED;
- freez(new_url);
- return finish_http_response(csp, rsp);
- }
- }
- /* Only reached if no redirect is required */
- return NULL;
- }
- #ifdef FEATURE_IMAGE_BLOCKING
- /*********************************************************************
- *
- * Function : is_imageurl
- *
- * Description : Given a URL, decide whether it should be treated
- * as image URL or not.
- *
- * Parameters :
- * 1 : csp = Current client state (buffers, headers, etc...)
- *
- * Returns : True (nonzero) if URL is an image URL, false (0)
- * otherwise
- *
- *********************************************************************/
- int is_imageurl(const struct client_state *csp)
- {
- return ((csp->action->flags & ACTION_IMAGE) != 0);
- }
- #endif /* def FEATURE_IMAGE_BLOCKING */
- #ifdef FEATURE_TRUST
- /*********************************************************************
- *
- * Function : is_untrusted_url
- *
- * Description : Should we "distrust" this URL (and block it)?
- *
- * Yes if it matches a line in the trustfile, or if the
- * referrer matches a line starting with "+" in the
- * trustfile.
- * No otherwise.
- *
- * Parameters :
- * 1 : csp = Current client state (buffers, headers, etc...)
- *
- * Returns : 0 => trusted, 1 => untrusted
- *
- *********************************************************************/
- int is_untrusted_url(const struct client_state *csp)
- {
- struct file_list *fl;
- struct block_spec *b;
- struct pattern_spec **trusted_url;
- struct http_request rhttp[1];
- const char * referer;
- jb_err err;
- /*
- * If we don't have a trustlist, we trust everybody
- */
- if (((fl = csp->tlist) == NULL) || ((b = fl->f) == NULL))
- {
- return 0;
- }
- memset(rhttp, '\0', sizeof(*rhttp));
- /*
- * Do we trust the request URL itself?
- */
- for (b = b->next; b ; b = b->next)
- {
- if (url_match(b->url, csp->http))
- {
- return b->reject;
- }
- }
- if (NULL == (referer = get_header_value(csp->headers, "Referer:")))
- {
- /* no referrer was supplied */
- return 1;
- }
- /*
- * If not, do we maybe trust its referrer?
- */
- err = parse_http_url(referer, rhttp, REQUIRE_PROTOCOL);
- if (err)
- {
- return 1;
- }
- for (trusted_url = csp->config->trust_list; *trusted_url != NULL; trusted_url++)
- {
- if (url_match(*trusted_url, rhttp))
- {
- /* if the URL's referrer is from a trusted referrer, then
- * add the target spec to the trustfile as an unblocked
- * domain and return 0 (which means it's OK).
- */
- FILE *fp;
- if (NULL != (fp = fopen(csp->config->trustfile, "a")))
- {
- char * path;
- char * path_end;
- char * new_entry = strdup_or_die("~");
- string_append(&new_entry, csp->http->hostport);
- path = csp->http->path;
- if ( (path[0] == '/')
- && (path[1] == '~')
- && ((path_end = strchr(path + 2, '/')) != NULL))
- {
- /* since this path points into a user's home space
- * be sure to include this spec in the trustfile.
- */
- long path_len = path_end - path; /* save offset */
- path = strdup(path); /* Copy string */
- if (path != NULL)
- {
- path_end = path + path_len; /* regenerate ptr to new buffer */
- *(path_end + 1) = '\0'; /* Truncate path after '/' */
- }
- string_join(&new_entry, path);
- }
- /*
- * Give a reason for generating this entry.
- */
- string_append(&new_entry, " # Trusted referrer was: ");
- string_append(&new_entry, referer);
- if (new_entry != NULL)
- {
- if (-1 == fprintf(fp, "%s\n", new_entry))
- {
- log_error(LOG_LEVEL_ERROR, "Failed to append \'%s\' to trustfile \'%s\': %E",
- new_entry, csp->config->trustfile);
- }
- freez(new_entry);
- }
- else
- {
- /* FIXME: No way to handle out-of memory, so mostly ignoring it */
- log_error(LOG_LEVEL_ERROR, "Out of memory adding pattern to trust file");
- }
- fclose(fp);
- }
- else
- {
- log_error(LOG_LEVEL_ERROR, "Failed to append new entry for \'%s\' to trustfile \'%s\': %E",
- csp->http->hostport, csp->config->trustfile);
- }
- return 0;
- }
- }
- return 1;
- }
- #endif /* def FEATURE_TRUST */
- /*********************************************************************
- *
- * Function : get_filter
- *
- * Description : Get a filter with a given name and type.
- * Note that taggers are filters, too.
- *
- * Parameters :
- * 1 : csp = Current client state (buffers, headers, etc...)
- * 2 : requested_name = Name of the content filter to get
- * 3 : requested_type = Type of the filter to tagger to lookup
- *
- * Returns : A pointer to the requested filter
- * or NULL if the filter wasn't found
- *
- *********************************************************************/
- struct re_filterfile_spec *get_filter(const struct client_state *csp,
- const char *requested_name,
- enum filter_type requested_type)
- {
- int i;
- struct re_filterfile_spec *b;
- struct file_list *fl;
- for (i = 0; i < MAX_AF_FILES; i++)
- {
- fl = csp->rlist[i];
- if ((NULL == fl) || (NULL == fl->f))
- {
- /*
- * Either there are no filter files left or this
- * filter file just contains no valid filters.
- *
- * Continue to be sure we don't miss valid filter
- * files that are chained after empty or invalid ones.
- */
- continue;
- }
- for (b = fl->f; b != NULL; b = b->next)
- {
- if (b->type != requested_type)
- {
- /* The callers isn't interested in this filter type. */
- continue;
- }
- if (strcmp(b->name, requested_name) == 0)
- {
- /* The requested filter has been found. Abort search. */
- return b;
- }
- }
- }
- /* No filter with the given name and type exists. */
- return NULL;
- }
- /*********************************************************************
- *
- * Function : pcrs_filter_response
- *
- * Description : Execute all text substitutions from all applying
- * +filter actions on the text buffer that's been
- * accumulated in csp->iob->buf.
- *
- * Parameters :
- * 1 : csp = Current client state (buffers, headers, etc...)
- *
- * Returns : a pointer to the (newly allocated) modified buffer.
- * or NULL if there were no hits or something went wrong
- *
- *********************************************************************/
- static char *pcrs_filter_response(struct client_state *csp)
- {
- int hits = 0;
- size_t size, prev_size;
- char *old = NULL;
- char *new = NULL;
- pcrs_job *job;
- struct re_filterfile_spec *b;
- struct list_entry *filtername;
- /*
- * Sanity first
- */
- if (csp->iob->cur >= csp->iob->eod)
- {
- return(NULL);
- }
- if (filters_available(csp) == FALSE)
- {
- log_error(LOG_LEVEL_ERROR, "Inconsistent configuration: "
- "content filtering enabled, but no content filters available.");
- return(NULL);
- }
- size = (size_t)(csp->iob->eod - csp->iob->cur);
- old = csp->iob->cur;
- /*
- * For all applying +filter actions, look if a filter by that
- * name exists and if yes, execute it's pcrs_joblist on the
- * buffer.
- */
- for (filtername = csp->action->multi[ACTION_MULTI_FILTER]->first;
- filtername != NULL; filtername = filtername->next)
- {
- int current_hits = 0; /* Number of hits caused by this filter */
- int job_number = 0; /* Which job we're currently executing */
- int job_hits = 0; /* How many hits the current job caused */
- pcrs_job *joblist;
- b = get_filter(csp, filtername->str, FT_CONTENT_FILTER);
- if (b == NULL)
- {
- continue;
- }
- joblist = b->joblist;
- if (b->dynamic) joblist = compile_dynamic_pcrs_job_list(csp, b);
- if (NULL == joblist)
- {
- log_error(LOG_LEVEL_RE_FILTER, "Filter %s has empty joblist. Nothing to do.", b->name);
- continue;
- }
- prev_size = size;
- /* Apply all jobs from the joblist */
- for (job = joblist; NULL != job; job = job->next)
- {
- job_number++;
- job_hits = pcrs_execute(job, old, size, &new, &size);
- if (job_hits >= 0)
- {
- /*
- * That went well. Continue filtering
- * and use the result of this job as
- * input for the next one.
- */
- current_hits += job_hits;
- if (old != csp->iob->cur)
- {
- freez(old);
- }
- old = new;
- }
- else
- {
- /*
- * This job caused an unexpected error. Inform the user
- * and skip the rest of the jobs in this filter. We could
- * continue with the next job, but usually the jobs
- * depend on each other or are similar enough to
- * fail for the same reason.
- *
- * At the moment our pcrs expects the error codes of pcre 3.4,
- * but newer pcre versions can return additional error codes.
- * As a result pcrs_strerror()'s error message might be
- * "Unknown error ...", therefore we print the numerical value
- * as well.
- *
- * XXX: Is this important enough for LOG_LEVEL_ERROR or
- * should we use LOG_LEVEL_RE_FILTER instead?
- */
- log_error(LOG_LEVEL_ERROR, "Skipped filter \'%s\' after job number %u: %s (%d)",
- b->name, job_number, pcrs_strerror(job_hits), job_hits);
- break;
- }
- }
- if (b->dynamic) pcrs_free_joblist(joblist);
- log_error(LOG_LEVEL_RE_FILTER,
- "filtering %s%s (size %lu) with \'%s\' produced %d hits (new size %lu).",
- csp->http->hostport, csp->http->path, prev_size, b->name, current_hits, size);
- #ifdef FEATURE_EXTENDED_STATISTICS
- update_filter_statistics(b->name, current_hits);
- #endif
- hits += current_hits;
- }
- /*
- * If there were no hits, destroy our copy and let
- * chat() use the original in csp->iob
- */
- if (!hits)
- {
- if (old != csp->iob->cur && old != new)
- {
- freez(old);
- }
- freez(new);
- return(NULL);
- }
- csp->flags |= CSP_FLAG_MODIFIED;
- csp->content_length = size;
- clear_iob(csp->iob);
- return(new);
- }
- #ifdef FEATURE_EXTERNAL_FILTERS
- /*********************************************************************
- *
- * Function : get_external_filter
- *
- * Description : Lookup the code to execute for an external filter.
- * Masks the misuse of the re_filterfile_spec.
- *
- * Parameters :
- * 1 : csp = Current client state (buffers, headers, etc...)
- * 2 : name = Name of the content filter to get
- *
- * Returns : A pointer to the requested code
- * or NULL if the filter wasn't found
- *
- *********************************************************************/
- static const char *get_external_filter(const struct client_state *csp,
- const char *name)
- {
- struct re_filterfile_spec *external_filter;
- external_filter = get_filter(csp, name, FT_EXTERNAL_CONTENT_FILTER);
- if (external_filter == NULL)
- {
- log_error(LOG_LEVEL_FATAL,
- "Didn't find stuff to execute for external filter: %s",
- name);
- }
- return external_filter->patterns->first->str;
- }
- /*********************************************************************
- *
- * Function : set_privoxy_variables
- *
- * Description : Sets a couple of privoxy-specific environment variables
- *
- * Parameters :
- * 1 : csp = Current client state (buffers, headers, etc...)
- *
- * Returns : N/A
- *
- *********************************************************************/
- static void set_privoxy_variables(const struct client_state *csp)
- {
- int i;
- struct {
- const char *name;
- const char *value;
- } env[] = {
- { "PRIVOXY_URL", csp->http->url },
- { "PRIVOXY_PATH", csp->http->path },
- { "PRIVOXY_HOST", csp->http->host },
- { "PRIVOXY_ORIGIN", csp->ip_addr_str },
- { "PRIVOXY_LISTEN_ADDRESS", csp->listen_addr_str },
- };
- for (i = 0; i < SZ(env); i++)
- {
- if (setenv(env[i].name, env[i].value, 1))
- {
- log_error(LOG_LEVEL_ERROR, "Failed to set %s=%s: %E",
- env[i].name, env[i].value);
- }
- }
- }
- /*********************************************************************
- *
- * Function : execute_external_filter
- *
- * Description : Pipe content into external filter and return the output
- *
- * Parameters :
- * 1 : csp = Current client state (buffers, headers, etc...)
- * 2 : name = Name of the external filter to execute
- * 3 : content = The original content to filter
- * 4 : size = The size of the content buffer
- *
- * Returns : a pointer to the (newly allocated) modified buffer.
- * or NULL if there were no hits or something went wrong
- *
- *********************************************************************/
- static char *execute_external_filter(const struct client_state *csp,
- const char *name, char *content, size_t *size)
- {
- char cmd[200];
- char file_name[FILENAME_MAX];
- FILE *fp;
- char *filter_output;
- int fd;
- int ret;
- size_t new_size;
- const char *external_filter;
- if (csp->config->temporary_directory == NULL)
- {
- log_error(LOG_LEVEL_ERROR,
- "No temporary-directory configured. Can't execute filter: %s",
- name);
- return NULL;
- }
- external_filter = get_external_filter(csp, name);
- if (sizeof(file_name) < snprintf(file_name, sizeof(file_name),
- "%s/privoxy-XXXXXXXX", csp->config->temporary_directory))
- {
- log_error(LOG_LEVEL_ERROR, "temporary-directory path too long");
- return NULL;
- }
- fd = mkstemp(file_name);
- if (fd == -1)
- {
- log_error(LOG_LEVEL_ERROR, "mkstemp() failed to create %s: %E", file_name);
- return NULL;
- }
- fp = fdopen(fd, "w");
- if (fp == NULL)
- {
- log_error(LOG_LEVEL_ERROR, "fdopen() failed: %E");
- unlink(file_name);
- return NULL;
- }
- /*
- * The size may be zero if a previous filter discarded everything.
- *
- * This isn't necessary unintentional, so we just don't try
- * to fwrite() nothing and let the user deal with the rest.
- */
- if ((*size != 0) && fwrite(content, *size, 1, fp) != 1)
- {
- log_error(LOG_LEVEL_ERROR, "fwrite(..., %lu, 1, ..) failed: %E", *size);
- unlink(file_name);
- fclose(fp);
- return NULL;
- }
- fclose(fp);
- if (sizeof(cmd) < snprintf(cmd, sizeof(cmd), "%s < %s", external_filter, file_name))
- {
- log_error(LOG_LEVEL_ERROR,
- "temporary-directory or external filter path too long");
- unlink(file_name);
- return NULL;
- }
- log_error(LOG_LEVEL_RE_FILTER, "Executing '%s': %s", name, cmd);
- /*
- * The locking is necessary to prevent other threads
- * from overwriting the environment variables before
- * the popen fork. Afterwards this no longer matters.
- */
- privoxy_mutex_lock(&external_filter_mutex);
- set_privoxy_variables(csp);
- fp = popen(cmd, "r");
- privoxy_mutex_unlock(&external_filter_mutex);
- if (fp == NULL)
- {
- log_error(LOG_LEVEL_ERROR, "popen(\"%s\", \"r\") failed: %E", cmd);
- unlink(file_name);
- return NULL;
- }
- /* Allocate at least one byte */
- filter_output = malloc_or_die(*size + 1);
- new_size = 0;
- while (!feof(fp) && !ferror(fp))
- {
- size_t len;
- /* Could be bigger ... */
- enum { READ_LENGTH = 2048 };
- if (new_size + READ_LENGTH >= *size)
- {
- char *p;
- /* Could be considered wasteful if the content is 'large'. */
- *size += (*size >= READ_LENGTH) ? *size : READ_LENGTH;
- p = realloc(filter_output, *size);
- if (p == NULL)
- {
- log_error(LOG_LEVEL_ERROR, "Out of memory while reading "
- "external filter output. Using what we got so far.");
- break;
- }
- filter_output = p;
- }
- assert(new_size + READ_LENGTH < *size);
- len = fread(&filter_output[new_size], 1, READ_LENGTH, fp);
- if (len > 0)
- {
- new_size += len;
- }
- }
- ret = pclose(fp);
- if (ret == -1)
- {
- log_error(LOG_LEVEL_ERROR, "Executing %s failed: %E", cmd);
- }
- else
- {
- log_error(LOG_LEVEL_RE_FILTER,
- "Executing '%s' resulted in return value %d. "
- "Read %lu of up to %lu bytes.", name, (ret >> 8), new_size, *size);
- }
- unlink(file_name);
- *size = new_size;
- return filter_output;
- }
- #endif /* def FEATURE_EXTERNAL_FILTERS */
- /*********************************************************************
- *
- * Function : gif_deanimate_response
- *
- * Description : Deanimate the GIF image that has been accumulated in
- * csp->iob->buf, set csp->content_length to the modified
- * size and raise the CSP_FLAG_MODIFIED flag.
- *
- * Parameters :
- * 1 : csp = Current client state (buffers, headers, etc...)
- *
- * Returns : a pointer to the (newly allocated) modified buffer.
- * or NULL in case something went wrong.
- *
- *********************************************************************/
- #ifdef FUZZ
- char *gif_deanimate_response(struct client_state *csp)
- #else
- static char *gif_deanimate_response(struct client_state *csp)
- #endif
- {
- struct binbuffer *in, *out;
- char *p;
- size_t size;
- size = (size_t)(csp->iob->eod - csp->iob->cur);
- in = zalloc_or_die(sizeof(*in));
- out = zalloc_or_die(sizeof(*out));
- in->buffer = csp->iob->cur;
- in->size = size;
- if (gif_deanimate(in, out, strncmp("last", csp->action->string[ACTION_STRING_DEANIMATE], 4)))
- {
- log_error(LOG_LEVEL_DEANIMATE, "failed! (gif parsing)");
- freez(in);
- buf_free(out);
- return(NULL);
- }
- else
- {
- if ((int)size == out->offset)
- {
- log_error(LOG_LEVEL_DEANIMATE, "GIF not changed.");
- }
- else
- {
- log_error(LOG_LEVEL_DEANIMATE,
- "Success! GIF shrunk from %lu bytes to %lu.", size, out->offset);
- }
- csp->content_length = out->offset;
- csp->flags |= CSP_FLAG_MODIFIED;
- p = out->buffer;
- freez(in);
- freez(out);
- return(p);
- }
- }
- /*********************************************************************
- *
- * Function : get_filter_function
- *
- * Description : Decides which content filter function has
- * to be applied (if any). Only considers functions
- * for internal filters which are mutually-exclusive.
- *
- * Parameters :
- * 1 : csp = Current client state (buffers, headers, etc...)
- *
- * Returns : The content filter function to run, or
- * NULL if no content filter is active
- *
- *********************************************************************/
- static filter_function_ptr get_filter_function(const struct client_state *csp)
- {
- filter_function_ptr filter_function = NULL;
- /*
- * Choose the applying filter function based on
- * the content type and action settings.
- */
- if ((csp->content_type & CT_TEXT) &&
- (!list_is_empty(csp->action->multi[ACTION_MULTI_FILTER])))
- {
- filter_function = pcrs_filter_response;
- }
- else if ((csp->content_type & CT_GIF) &&
- (csp->action->flags & ACTION_DEANIMATE))
- {
- filter_function = gif_deanimate_response;
- }
- return filter_function;
- }
- /*********************************************************************
- *
- * Function : remove_chunked_transfer_coding
- *
- * Description : In-situ remove the "chunked" transfer coding as defined
- * in RFC 7230 4.1 from a buffer. XXX: The implementation
- * is neither complete nor compliant (TODO #129).
- *
- * Parameters :
- * 1 : buffer = Pointer to the text buffer
- * 2 : size = In: Number of bytes to be processed,
- * Out: Number of bytes after de-chunking.
- * (undefined in case of errors)
- *
- * Returns : JB_ERR_OK for success,
- * JB_ERR_PARSE otherwise
- *
- *********************************************************************/
- #ifdef FUZZ
- extern jb_err remove_chunked_transfer_coding(char *buffer, size_t *size)
- #else
- static jb_err remove_chunked_transfer_coding(char *buffer, size_t *size)
- #endif
- {
- size_t newsize = 0;
- unsigned int chunksize = 0;
- char *from_p, *to_p;
- const char *end_of_buffer = buffer + *size;
- if (*size == 0)
- {
- log_error(LOG_LEVEL_FATAL, "Invalid chunked input. Buffer is empty.");
- return JB_ERR_PARSE;
- }
- assert(buffer);
- from_p = to_p = buffer;
- if (sscanf(buffer, "%x", &chunksize) != 1)
- {
- log_error(LOG_LEVEL_ERROR, "Invalid first chunksize while stripping \"chunked\" transfer coding");
- return JB_ERR_PARSE;
- }
- while (chunksize > 0U)
- {
- /*
- * If the chunk-size is valid, we should have at least
- * chunk-size bytes of chunk-data and five bytes of
- * meta data (chunk-size, CRLF, CRLF) left in the buffer.
- */
- if (chunksize + 5 >= *size - newsize)
- {
- log_error(LOG_LEVEL_ERROR,
- "Chunk size %u exceeds buffered data left. "
- "Already digested %lu of %lu buffered bytes.",
- chunksize, newsize, *size);
- return JB_ERR_PARSE;
- }
- /*
- * Skip the chunk-size, the optional chunk-ext and the CRLF
- * that is supposed to be located directly before the start
- * of chunk-data.
- */
- if (NULL == (from_p = strstr(from_p, "\r\n")))
- {
- log_error(LOG_LEVEL_ERROR, "Parse error while stripping \"chunked\" transfer coding");
- return JB_ERR_PARSE;
- }
- from_p += 2;
- /*
- * The previous strstr() does not enforce chunk-validity
- * and is sattisfied as long a CRLF is left in the buffer.
- *
- * Make sure the bytes we consider chunk-data are within
- * the valid range.
- */
- if (from_p + chunksize >= end_of_buffer)
- {
- log_error(LOG_LEVEL_ERROR,
- "End of chunk is beyond the end of the buffer.");
- return JB_ERR_PARSE;
- }
- memmove(to_p, from_p, (size_t) chunksize);
- newsize += chunksize;
- to_p = buffer + newsize;
- from_p += chunksize;
- /*
- * Not merging this check with the previous one allows us
- * to keep chunks without trailing CRLF. It's not clear
- * if we actually have to care about those, though.
- */
- if (from_p + 2 >= end_of_buffer)
- {
- log_error(LOG_LEVEL_ERROR, "Not enough room for trailing CRLF.");
- return JB_ERR_PARSE;
- }
- from_p += 2;
- if (sscanf(from_p, "%x", &chunksize) != 1)
- {
- log_error(LOG_LEVEL_INFO, "Invalid \"chunked\" transfer encoding detected and ignored.");
- break;
- }
- }
- /* XXX: Should get its own loglevel. */
- log_error(LOG_LEVEL_RE_FILTER,
- "De-chunking successful. Shrunk from %lu to %lu", *size, newsize);
- *size = newsize;
- return JB_ERR_OK;
- }
- /*********************************************************************
- *
- * Function : prepare_for_filtering
- *
- * Description : If necessary, de-chunks and decompresses
- * the content so it can get filterd.
- *
- * Parameters :
- * 1 : csp = Current client state (buffers, headers, etc...)
- *
- * Returns : JB_ERR_OK for success,
- * JB_ERR_PARSE otherwise
- *
- *********************************************************************/
- static jb_err prepare_for_filtering(struct client_state *csp)
- {
- jb_err err = JB_ERR_OK;
- /*
- * If the body has a "chunked" transfer-encoding,
- * get rid of it, adjusting size and iob->eod
- */
- if (csp->flags & CSP_FLAG_CHUNKED)
- {
- size_t size = (size_t)(csp->iob->eod - csp->iob->cur);
- log_error(LOG_LEVEL_RE_FILTER, "Need to de-chunk first");
- err = remove_chunked_transfer_coding(csp->iob->cur, &size);
- if (JB_ERR_OK == err)
- {
- csp->iob->eod = csp->iob->cur + size;
- csp->flags |= CSP_FLAG_MODIFIED;
- }
- else
- {
- return JB_ERR_PARSE;
- }
- }
- #ifdef FEATURE_ZLIB
- /*
- * If the body has a supported transfer-encoding,
- * decompress it, adjusting size and iob->eod.
- */
- if ((csp->content_type & (CT_GZIP|CT_DEFLATE))
- #ifdef FEATURE_BROTLI
- || (csp->content_type & CT_BROTLI)
- #endif
- )
- {
- if (0 == csp->iob->eod - csp->iob->cur)
- {
- /* Nothing left after de-chunking. */
- return JB_ERR_OK;
- }
- err = decompress_iob(csp);
- if (JB_ERR_OK == err)
- {
- csp->flags |= CSP_FLAG_MODIFIED;
- csp->content_type &= ~CT_TABOO;
- }
- else
- {
- /*
- * Unset content types to remember not to
- * modify the Content-Encoding header later.
- */
- csp->content_type &= ~CT_GZIP;
- csp->content_type &= ~CT_DEFLATE;
- #ifdef FEATURE_BROTLI
- csp->content_type &= ~CT_BROTLI;
- #endif
- }
- }
- #endif
- return err;
- }
- /*********************************************************************
- *
- * Function : execute_content_filters
- *
- * Description : Executes a given content filter.
- *
- * Parameters :
- * 1 : csp = Current client state (buffers, headers, etc...)
- *
- * Returns : Pointer to the modified buffer, or
- * NULL if filtering failed or wasn't necessary.
- *
- *********************************************************************/
- char *execute_content_filters(struct client_state *csp)
- {
- char *content;
- filter_function_ptr content_filter;
- assert(content_filters_enabled(csp->action));
- if (0 == csp->iob->eod - csp->iob->cur)
- {
- /*
- * No content (probably status code 301, 302 ...),
- * no filtering necessary.
- */
- return NULL;
- }
- if (JB_ERR_OK != prepare_for_filtering(csp))
- {
- /*
- * failed to de-chunk or decompress.
- */
- return NULL;
- }
- if (0 == csp->iob->eod - csp->iob->cur)
- {
- /*
- * Clown alarm: chunked and/or compressed nothing delivered.
- */
- return NULL;
- }
- content_filter = get_filter_function(csp);
- content = (content_filter != NULL) ? (*content_filter)(csp) : NULL;
- #ifdef FEATURE_EXTERNAL_FILTERS
- if ((csp->content_type & CT_TEXT) &&
- !list_is_empty(csp->action->multi[ACTION_MULTI_EXTERNAL_FILTER]))
- {
- struct list_entry *filtername;
- size_t size = (size_t)csp->content_length;
- if (content == NULL)
- {
- content = csp->iob->cur;
- size = (size_t)(csp->iob->eod - csp->iob->cur);
- }
- for (filtername = csp->action->multi[ACTION_MULTI_EXTERNAL_FILTER]->first;
- filtername ; filtername = filtername->next)
- {
- char *result = execute_external_filter(csp, filtername->str, content, &size);
- if (result != NULL)
- {
- if (content != csp->iob->cur)
- {
- free(content);
- }
- content = result;
- }
- }
- csp->flags |= CSP_FLAG_MODIFIED;
- csp->content_length = size;
- }
- #endif /* def FEATURE_EXTERNAL_FILTERS */
- return content;
- }
- /*********************************************************************
- *
- * Function : get_url_actions
- *
- * Description : Gets the actions for this URL.
- *
- * Parameters :
- * 1 : csp = Current client state (buffers, headers, etc...)
- * 2 : http = http_request request for blocked URLs
- *
- * Returns : N/A
- *
- *********************************************************************/
- void get_url_actions(struct client_state *csp, struct http_request *http)
- {
- struct file_list *fl;
- struct url_actions *b;
- int i;
- init_current_action(csp->action);
- for (i = 0; i < MAX_AF_FILES; i++)
- {
- if (((fl = csp->actions_list[i]) == NULL) || ((b = fl->f) == NULL))
- {
- return;
- }
- #ifdef FEATURE_CLIENT_TAGS
- apply_url_actions(csp->action, http, csp->client_tags, b);
- #else
- apply_url_actions(csp->action, http, b);
- #endif
- }
- return;
- }
- /*********************************************************************
- *
- * Function : apply_url_actions
- *
- * Description : Applies a list of URL actions.
- *
- * Parameters :
- * 1 : action = Destination.
- * 2 : http = Current URL
- * 3 : client_tags = list of client tags
- * 4 : b = list of URL actions to apply
- *
- * Returns : N/A
- *
- *********************************************************************/
- static void apply_url_actions(struct current_action_spec *action,
- struct http_request *http,
- #ifdef FEATURE_CLIENT_TAGS
- const struct list *client_tags,
- #endif
- struct url_actions *b)
- {
- if (b == NULL)
- {
- /* Should never happen */
- return;
- }
- for (b = b->next; NULL != b; b = b->next)
- {
- if (url_match(b->url, http))
- {
- merge_current_action(action, b->action);
- }
- #ifdef FEATURE_CLIENT_TAGS
- if (client_tag_match(b->url, client_tags))
- {
- merge_current_action(action, b->action);
- }
- #endif
- }
- }
- /*********************************************************************
- *
- * Function : get_forward_override_settings
- *
- * Description : Returns forward settings as specified with the
- * forward-override{} action. forward-override accepts
- * forward lines similar to the one used in the
- * configuration file, but without the URL pattern.
- *
- * For example:
- *
- * forward / .
- *
- * in the configuration file can be replaced with
- * the action section:
- *
- * {+forward-override{forward .}}
- * /
- *
- * Parameters :
- * 1 : csp = Current client state (buffers, headers, etc...)
- *
- * Returns : Pointer to forwarding structure in case of success.
- * Invalid syntax is fatal.
- *
- *********************************************************************/
- static const struct forward_spec *get_forward_override_settings(struct client_state *csp)
- {
- const char *forward_override_line = csp->action->string[ACTION_STRING_FORWARD_OVERRIDE];
- char forward_settings[BUFFER_SIZE];
- char *http_parent = NULL;
- /* variable names were chosen for consistency reasons. */
- struct forward_spec *fwd = NULL;
- int vec_count;
- char *vec[3];
- assert(csp->action->flags & ACTION_FORWARD_OVERRIDE);
- /* Should be enforced by load_one_actions_file() */
- assert(strlen(forward_override_line) < sizeof(forward_settings) - 1);
- /* Create a copy ssplit can modify */
- strlcpy(forward_settings, forward_override_line, sizeof(forward_settings));
- if (NULL != csp->fwd)
- {
- /*
- * XXX: Currently necessary to prevent memory
- * leaks when the show-url-info cgi page is visited.
- */
- unload_forward_spec(csp->fwd);
- }
- /*
- * allocate a new forward node, valid only for
- * the lifetime of this request. Save its location
- * in csp as well, so sweep() can free it later on.
- */
- fwd = csp->fwd = zalloc_or_die(sizeof(*fwd));
- vec_count = ssplit(forward_settings, " \t", vec, SZ(vec));
- if ((vec_count == 2) && !strcasecmp(vec[0], "forward"))
- {
- fwd->type = SOCKS_NONE;
- /* Parse the parent HTTP proxy host:port */
- http_parent = vec[1];
- }
- else if ((vec_count == 2) && !strcasecmp(vec[0], "forward-webserver"))
- {
- fwd->type = FORWARD_WEBSERVER;
- /* Parse the parent HTTP server host:port */
- http_parent = vec[1];
- }
- else if (vec_count == 3)
- {
- char *socks_proxy = NULL;
- if (!strcasecmp(vec[0], "forward-socks4"))
- {
- fwd->type = SOCKS_4;
- socks_proxy = vec[1];
- }
- else if (!strcasecmp(vec[0], "forward-socks4a"))
- {
- fwd->type = SOCKS_4A;
- socks_proxy = vec[1];
- }
- else if (!strcasecmp(vec[0], "forward-socks5"))
- {
- fwd->type = SOCKS_5;
- socks_proxy = vec[1];
- }
- else if (!strcasecmp(vec[0], "forward-socks5t"))
- {
- fwd->type = SOCKS_5T;
- socks_proxy = vec[1];
- }
- if (NULL != socks_proxy)
- {
- /* Parse the SOCKS proxy [user:pass@]host[:port] */
- fwd->gateway_port = 1080;
- parse_forwarder_address(socks_proxy,
- &fwd->gateway_host, &fwd->gateway_port,
- &fwd->auth_username, &fwd->auth_password);
- http_parent = vec[2];
- }
- }
- if (NULL == http_parent)
- {
- log_error(LOG_LEVEL_FATAL,
- "Invalid forward-override syntax in: %s", forward_override_line);
- /* Never get here - LOG_LEVEL_FATAL causes program exit */
- }
- /* Parse http forwarding settings */
- if (strcmp(http_parent, ".") != 0)
- {
- fwd->forward_port = 8000;
- parse_forwarder_address(http_parent,
- &fwd->forward_host, &fwd->forward_port,
- NULL, NULL);
- }
- assert (NULL != fwd);
- log_error(LOG_LEVEL_CONNECT,
- "Overriding forwarding settings based on \'%s\'", forward_override_line);
- return fwd;
- }
- /*********************************************************************
- *
- * Function : forward_url
- *
- * Description : Should we forward this to another proxy?
- *
- * Parameters :
- * 1 : csp = Current client state (buffers, headers, etc...)
- * 2 : http = http_request request for current URL
- *
- * Returns : Pointer to forwarding information.
- *
- *********************************************************************/
- const struct forward_spec *forward_url(struct client_state *csp,
- const struct http_request *http)
- {
- static const struct forward_spec fwd_default[1]; /* Zero'ed due to being static. */
- struct forward_spec *fwd = csp->config->forward;
- if (csp->action->flags & ACTION_FORWARD_OVERRIDE)
- {
- return get_forward_override_settings(csp);
- }
- if (fwd == NULL)
- {
- return fwd_default;
- }
- while (fwd != NULL)
- {
- if (url_match(fwd->url, http))
- {
- return fwd;
- }
- fwd = fwd->next;
- }
- return fwd_default;
- }
- /*********************************************************************
- *
- * Function : direct_response
- *
- * Description : Check if Max-Forwards == 0 for an OPTIONS or TRACE
- * request and if so, return a HTTP 501 to the client.
- *
- * FIXME: I have a stupid name and I should handle the
- * requests properly. Still, what we do here is rfc-
- * compliant, whereas ignoring or forwarding are not.
- *
- * Parameters :
- * 1 : csp = Current client state (buffers, headers, etc...)
- *
- * Returns : http_response if , NULL if nonmatch or handler fail
- *
- *********************************************************************/
- struct http_response *direct_response(struct client_state *csp)
- {
- struct http_response *rsp;
- struct list_entry *p;
- if ((0 == strcmpic(csp->http->gpc, "trace"))
- || (0 == strcmpic(csp->http->gpc, "options")))
- {
- for (p = csp->headers->first; (p != NULL) ; p = p->next)
- {
- if (!strncmpic(p->str, "Max-Forwards:", 13))
- {
- unsigned int max_forwards;
- /*
- * If it's a Max-Forwards value of zero,
- * we have to intercept the request.
- */
- if (1 == sscanf(p->str+12, ": %u", &max_forwards) && max_forwards == 0)
- {
- /*
- * FIXME: We could handle at least TRACE here,
- * but that would require a verbatim copy of
- * the request which we don't have anymore
- */
- log_error(LOG_LEVEL_HEADER,
- "Detected header \'%s\' in OPTIONS or TRACE request. Returning 501.",
- p->str);
- /* Get mem for response or fail*/
- if (NULL == (rsp = alloc_http_response()))
- {
- return cgi_error_memory();
- }
- rsp->status = strdup_or_die("501 Not Implemented");
- rsp->is_static = 1;
- rsp->crunch_reason = UNSUPPORTED;
- return(finish_http_response(csp, rsp));
- }
- }
- }
- }
- return NULL;
- }
- /*********************************************************************
- *
- * Function : content_requires_filtering
- *
- * Description : Checks whether there are any content filters
- * enabled for the current request and if they
- * can actually be applied..
- *
- * Parameters :
- * 1 : csp = Current client state (buffers, headers, etc...)
- *
- * Returns : TRUE for yes, FALSE otherwise
- *
- *********************************************************************/
- int content_requires_filtering(struct client_state *csp)
- {
- if ((csp->content_type & CT_TABOO)
- && !(csp->action->flags & ACTION_FORCE_TEXT_MODE))
- {
- return FALSE;
- }
- /*
- * Are we enabling text mode by force?
- */
- if (csp->action->flags & ACTION_FORCE_TEXT_MODE)
- {
- /*
- * Do we really have to?
- */
- if (csp->content_type & CT_TEXT)
- {
- log_error(LOG_LEVEL_HEADER, "Text mode is already enabled.");
- }
- else
- {
- csp->content_type |= CT_TEXT;
- log_error(LOG_LEVEL_HEADER, "Text mode enabled by force. Take cover!");
- }
- }
- if (!(csp->content_type & CT_DECLARED))
- {
- /*
- * The server didn't bother to declare a MIME-Type.
- * Assume it's text that can be filtered.
- *
- * This also regularly happens with 304 responses,
- * therefore logging anything here would cause
- * too much noise.
- */
- csp->content_type |= CT_TEXT;
- }
- /*
- * Choose the applying filter function based on
- * the content type and action settings.
- */
- if ((csp->content_type & CT_TEXT) &&
- (!list_is_empty(csp->action->multi[ACTION_MULTI_FILTER]) ||
- !list_is_empty(csp->action->multi[ACTION_MULTI_EXTERNAL_FILTER])))
- {
- return TRUE;
- }
- else if ((csp->content_type & CT_GIF) &&
- (csp->action->flags & ACTION_DEANIMATE))
- {
- return TRUE;
- }
- return FALSE;
- }
- /*********************************************************************
- *
- * Function : content_filters_enabled
- *
- * Description : Checks whether there are any content filters
- * enabled for the current request.
- *
- * Parameters :
- * 1 : action = Action spec to check.
- *
- * Returns : TRUE for yes, FALSE otherwise
- *
- *********************************************************************/
- int content_filters_enabled(const struct current_action_spec *action)
- {
- return ((action->flags & ACTION_DEANIMATE) ||
- !list_is_empty(action->multi[ACTION_MULTI_FILTER]) ||
- !list_is_empty(action->multi[ACTION_MULTI_EXTERNAL_FILTER]));
- }
- /*********************************************************************
- *
- * Function : filters_available
- *
- * Description : Checks whether there are any filters available.
- *
- * Parameters :
- * 1 : csp = Current client state (buffers, headers, etc...)
- *
- * Returns : TRUE for yes, FALSE otherwise.
- *
- *********************************************************************/
- int filters_available(const struct client_state *csp)
- {
- int i;
- for (i = 0; i < MAX_AF_FILES; i++)
- {
- const struct file_list *fl = csp->rlist[i];
- if ((NULL != fl) && (NULL != fl->f))
- {
- return TRUE;
- }
- }
- return FALSE;
- }
- #ifdef FEATURE_EXTENDED_STATISTICS
- struct filter_statistics_entry
- {
- char *filter;
- unsigned long long executions;
- unsigned long long response_bodies_modified;
- unsigned long long hits;
- struct filter_statistics_entry *next;
- };
- static struct filter_statistics_entry *filter_statistics = NULL;
- /*********************************************************************
- *
- * Function : register_filter_for_statistics
- *
- * Description : Registers a filter so we can gather statistics for
- * it unless the filter has already been registered
- * before.
- *
- * Parameters :
- * 1 : filter = Name of the filter to register
- *
- * Returns : void
- *
- *********************************************************************/
- void register_filter_for_statistics(const char *filter)
- {
- struct filter_statistics_entry *entry;
- privoxy_mutex_lock(&filter_statistics_mutex);
- if (filter_statistics == NULL)
- {
- filter_statistics = zalloc_or_die(sizeof(struct filter_statistics_entry));
- entry = filter_statistics;
- entry->filter = strdup_or_die(filter);
- privoxy_mutex_unlock(&filter_statistics_mutex);
- return;
- }
- entry = filter_statistics;
- while (entry != NULL)
- {
- if (!strcmp(entry->filter, filter))
- {
- /* Already registered, nothing to do. */
- break;
- }
- if (entry->next == NULL)
- {
- entry->next = zalloc_or_die(sizeof(struct filter_statistics_entry));
- entry->next->filter = strdup_or_die(filter);
- break;
- }
- entry = entry->next;
- }
- privoxy_mutex_unlock(&filter_statistics_mutex);
- }
- /*********************************************************************
- *
- * Function : update_filter_statistics
- *
- * Description : Updates the statistics for a filter.
- *
- * Parameters :
- * 1 : filter = Name of the filter to update
- * 2 : hits = Hit count.
- *
- * Returns : void
- *
- *********************************************************************/
- void update_filter_statistics(const char *filter, int hits)
- {
- struct filter_statistics_entry *entry;
- privoxy_mutex_lock(&filter_statistics_mutex);
- entry = filter_statistics;
- while (entry != NULL)
- {
- if (!strcmp(entry->filter, filter))
- {
- entry->executions++;
- if (hits != 0)
- {
- entry->response_bodies_modified++;
- entry->hits += (unsigned)hits;
- }
- break;
- }
- entry = entry->next;
- }
- privoxy_mutex_unlock(&filter_statistics_mutex);
- }
- /*********************************************************************
- *
- * Function : get_filter_statistics
- *
- * Description : Gets the statistics for a filter.
- *
- * Parameters :
- * 1 : filter = Name of the filter to get statistics for.
- * 2 : executions = Storage for the execution count.
- * 3 : response_bodies_modified = Storage for the number
- * of modified response bodies.
- * 4 : hits = Storage for the number of hits.
- *
- * Returns : void
- *
- *********************************************************************/
- void get_filter_statistics(const char *filter, unsigned long long *executions,
- unsigned long long *response_bodies_modified,
- unsigned long long *hits)
- {
- struct filter_statistics_entry *entry;
- privoxy_mutex_lock(&filter_statistics_mutex);
- entry = filter_statistics;
- while (entry != NULL)
- {
- if (!strcmp(entry->filter, filter))
- {
- *executions = entry->executions;
- *response_bodies_modified = entry->response_bodies_modified;
- *hits = entry->hits;
- break;
- }
- entry = entry->next;
- }
- privoxy_mutex_unlock(&filter_statistics_mutex);
- }
- struct block_statistics_entry
- {
- char *block_reason;
- unsigned long long count;
- struct block_statistics_entry *next;
- };
- static struct block_statistics_entry *block_statistics = NULL;
- /*********************************************************************
- *
- * Function : register_block_reason_for_statistics
- *
- * Description : Registers a block reason so we can gather statistics
- * for it unless the block reason has already been
- * registered before.
- *
- * Parameters :
- * 1 : block_reason = Block reason to register
- *
- * Returns : void
- *
- *********************************************************************/
- void register_block_reason_for_statistics(const char *block_reason)
- {
- struct block_statistics_entry *entry;
- privoxy_mutex_lock(&block_statistics_mutex);
- if (block_statistics == NULL)
- {
- block_statistics = zalloc_or_die(sizeof(struct block_statistics_entry));
- entry = block_statistics;
- entry->block_reason = strdup_or_die(block_reason);
- privoxy_mutex_unlock(&block_statistics_mutex);
- return;
- }
- entry = block_statistics;
- while (entry != NULL)
- {
- if (!strcmp(entry->block_reason, block_reason))
- {
- /* Already registered, nothing to do. */
- break;
- }
- if (entry->next == NULL)
- {
- entry->next = zalloc_or_die(sizeof(struct block_statistics_entry));
- entry->next->block_reason = strdup_or_die(block_reason);
- break;
- }
- entry = entry->next;
- }
- privoxy_mutex_unlock(&block_statistics_mutex);
- }
- /*********************************************************************
- *
- * Function : increment_block_reason_counter
- *
- * Description : Updates the counter for a block reason.
- *
- * Parameters :
- * 1 : block_reason = Block reason to count
- *
- * Returns : void
- *
- *********************************************************************/
- static void increment_block_reason_counter(const char *block_reason)
- {
- struct block_statistics_entry *entry;
- privoxy_mutex_lock(&block_statistics_mutex);
- entry = block_statistics;
- while (entry != NULL)
- {
- if (!strcmp(entry->block_reason, block_reason))
- {
- entry->count++;
- break;
- }
- entry = entry->next;
- }
- privoxy_mutex_unlock(&block_statistics_mutex);
- }
- /*********************************************************************
- *
- * Function : get_block_reason_count
- *
- * Description : Gets number of times a block reason was used.
- *
- * Parameters :
- * 1 : block_reason = Block reason to get statistics for.
- * 2 : count = Storage for the number of times the block
- * reason was used.
- *
- * Returns : void
- *
- *********************************************************************/
- void get_block_reason_count(const char *block_reason, unsigned long long *count)
- {
- struct block_statistics_entry *entry;
- privoxy_mutex_lock(&block_statistics_mutex);
- entry = block_statistics;
- while (entry != NULL)
- {
- if (!strcmp(entry->block_reason, block_reason))
- {
- *count = entry->count;
- break;
- }
- entry = entry->next;
- }
- privoxy_mutex_unlock(&block_statistics_mutex);
- }
- #endif /* def FEATURE_EXTENDED_STATISTICS */
- /*
- Local Variables:
- tab-width: 3
- end:
- */
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