X-Git-Url: http://www.privoxy.org/gitweb/?p=privoxy.git;a=blobdiff_plain;f=filters.c;h=c3aa3fd34491e0827a95f921335ae607b25c3d70;hp=3c3ae38e01905ba3e6ad7a6b133baacef20a5bb9;hb=41ae040b041e26c2e2b975120a6f1a2046c660f5;hpb=292da21cea2a42b0896d667cff7201ef0ea2894e diff --git a/filters.c b/filters.c index 3c3ae38e..c3aa3fd3 100644 --- a/filters.c +++ b/filters.c @@ -1,11 +1,11 @@ -const char filters_rcs[] = "$Id: filters.c,v 1.167 2012/03/04 11:51:25 fabiankeil Exp $"; +const char filters_rcs[] = "$Id: filters.c,v 1.200 2016/02/26 12:29:38 fabiankeil Exp $"; /********************************************************************* * * File : $Source: /cvsroot/ijbswa/current/filters.c,v $ * * Purpose : Declares functions to parse/crunch headers and pages. * - * Copyright : Written by and Copyright (C) 2001-2011 the + * Copyright : Written by and Copyright (C) 2001-2016 the * Privoxy team. http://www.privoxy.org/ * * Based on the Internet Junkbuster originally written @@ -65,10 +65,14 @@ const char filters_rcs[] = "$Id: filters.c,v 1.167 2012/03/04 11:51:25 fabiankei #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" @@ -80,6 +84,12 @@ typedef char *(*filter_function_ptr)(); static filter_function_ptr get_filter_function(const struct client_state *csp); static jb_err remove_chunked_transfer_coding(char *buffer, size_t *size); 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_ACL #ifdef HAVE_RFC2553 @@ -200,10 +210,6 @@ static int match_sockaddr(const struct sockaddr_storage *network, netmask_addr += 12; addr_len = 4; } - else if (network->ss_family != address->ss_family) - { - return 0; - } /* XXX: Port check is signaled in netmask */ if (*netmask_port && *network_port != *address_port) @@ -261,7 +267,7 @@ int block_acl(const struct access_control_addr *dst, const struct client_state * #else (csp->ip_addr_long & acl->src->mask) == acl->src->addr #endif - ) + ) { if (dst == NULL) { @@ -291,7 +297,7 @@ int block_acl(const struct access_control_addr *dst, const struct client_state * ((dst->addr & acl->dst->mask) == acl->dst->addr) && ((dst->port == acl->dst->port) || (acl->dst->port == 0)) #endif - ) + ) { if (acl->action == ACL_PERMIT) { @@ -350,12 +356,7 @@ int acl_addr(const char *aspec, struct access_control_addr *aca) * Use a temporary acl spec copy so we can log * the unmodified original in case of parse errors. */ - acl_spec = strdup(aspec); - if (acl_spec == NULL) - { - /* XXX: This will be logged as parse error. */ - return(-1); - } + acl_spec = strdup_or_die(aspec); if ((p = strchr(acl_spec, '/')) != NULL) { @@ -374,7 +375,7 @@ int acl_addr(const char *aspec, struct access_control_addr *aca) #else (masklength > 32) #endif - ) + ) { freez(acl_spec); return(-1); @@ -394,13 +395,19 @@ int acl_addr(const char *aspec, struct access_control_addr *aca) { 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) ? ++p : NULL), &hints, &result); + i = getaddrinfo(acl_spec, p, &hints, &result); if (i != 0) { @@ -419,7 +426,6 @@ int acl_addr(const char *aspec, struct access_control_addr *aca) { char *endptr; - *p++ = '\0'; port = strtol(p, &endptr, 10); if (port <= 0 || port > 65535 || *endptr != '\0') @@ -577,7 +583,7 @@ struct http_response *block_url(struct client_state *csp) /* determine HOW images should be blocked */ p = csp->action->string[ACTION_STRING_IMAGE_BLOCKER]; - if(csp->action->flags & ACTION_HANDLE_AS_EMPTY_DOCUMENT) + if (csp->action->flags & ACTION_HANDLE_AS_EMPTY_DOCUMENT) { log_error(LOG_LEVEL_ERROR, "handle-as-empty-document overruled by handle-as-image."); } @@ -585,12 +591,7 @@ struct http_response *block_url(struct client_state *csp) /* and handle accordingly: */ if ((p == NULL) || (0 == strcmpic(p, "pattern"))) { - rsp->status = strdup("403 Request blocked by Privoxy"); - if (rsp->status == NULL) - { - free_http_response(rsp); - return cgi_error_memory(); - } + rsp->status = strdup_or_die("403 Request blocked by Privoxy"); rsp->body = bindup(image_pattern_data, image_pattern_length); if (rsp->body == NULL) { @@ -607,12 +608,7 @@ struct http_response *block_url(struct client_state *csp) } else if (0 == strcmpic(p, "blank")) { - rsp->status = strdup("403 Request blocked by Privoxy"); - if (rsp->status == NULL) - { - free_http_response(rsp); - return cgi_error_memory(); - } + rsp->status = strdup_or_die("403 Request blocked by Privoxy"); rsp->body = bindup(image_blank_data, image_blank_length); if (rsp->body == NULL) { @@ -629,12 +625,7 @@ struct http_response *block_url(struct client_state *csp) } else { - rsp->status = strdup("302 Local Redirect from Privoxy"); - if (rsp->status == NULL) - { - free_http_response(rsp); - return cgi_error_memory(); - } + rsp->status = strdup_or_die("302 Local Redirect from Privoxy"); if (enlist_unique_header(rsp->headers, "Location", p)) { @@ -646,7 +637,7 @@ struct http_response *block_url(struct client_state *csp) } else #endif /* def FEATURE_IMAGE_BLOCKING */ - if(csp->action->flags & ACTION_HANDLE_AS_EMPTY_DOCUMENT) + if (csp->action->flags & ACTION_HANDLE_AS_EMPTY_DOCUMENT) { /* * Send empty document. @@ -654,7 +645,7 @@ struct http_response *block_url(struct client_state *csp) new_content_type = csp->action->string[ACTION_STRING_CONTENT_TYPE]; freez(rsp->body); - rsp->body = strdup(" "); + rsp->body = strdup_or_die(" "); rsp->content_length = 1; if (csp->config->feature_flags & RUNTIME_FEATURE_EMPTY_DOC_RETURNS_OK) @@ -665,18 +656,13 @@ struct http_response *block_url(struct client_state *csp) * 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("200 Request blocked by Privoxy"); + rsp->status = strdup_or_die("200 Request blocked by Privoxy"); } else { - rsp->status = strdup("403 Request blocked by Privoxy"); + rsp->status = strdup_or_die("403 Request blocked by Privoxy"); } - if (rsp->status == NULL) - { - free_http_response(rsp); - return cgi_error_memory(); - } if (new_content_type != 0) { log_error(LOG_LEVEL_HEADER, "Overwriting Content-Type with %s", new_content_type); @@ -696,12 +682,7 @@ struct http_response *block_url(struct client_state *csp) jb_err err; struct map * exports; - rsp->status = strdup("403 Request blocked by Privoxy"); - if (rsp->status == NULL) - { - free_http_response(rsp); - return cgi_error_memory(); - } + rsp->status = strdup_or_die("403 Request blocked by Privoxy"); exports = default_exports(csp, NULL); if (exports == NULL) @@ -785,8 +766,8 @@ struct http_response *trust_url(struct client_state *csp) struct map * exports; char buf[BUFFER_SIZE]; char *p; - struct url_spec **tl; - struct url_spec *t; + struct pattern_spec **tl; + struct pattern_spec *t; jb_err err; /* @@ -805,9 +786,9 @@ struct http_response *trust_url(struct client_state *csp) return cgi_error_memory(); } - rsp->status = strdup("403 Request blocked by Privoxy"); + rsp->status = strdup_or_die("403 Request blocked by Privoxy"); exports = default_exports(csp, NULL); - if (exports == NULL || rsp->status == NULL) + if (exports == NULL) { free_http_response(rsp); return cgi_error_memory(); @@ -839,7 +820,7 @@ struct http_response *trust_url(struct client_state *csp) /* * Export the trust list */ - p = strdup(""); + p = strdup_or_die(""); for (tl = csp->config->trust_list; (t = *tl) != NULL ; tl++) { snprintf(buf, sizeof(buf), "
  • %s
  • \n", t->spec); @@ -861,7 +842,7 @@ struct http_response *trust_url(struct client_state *csp) { struct list_entry *l; - p = strdup(""); + p = strdup_or_die(""); for (l = csp->config->trust_info->first; l ; l = l->next) { snprintf(buf, sizeof(buf), "
  • %s
    \n", l->str, l->str); @@ -1088,6 +1069,11 @@ char *get_last_url(char *subject, const char *redirect_mode) 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); @@ -1097,24 +1083,22 @@ char *get_last_url(char *subject, const char *redirect_mode) * go backwards through the segments, URL-decode them * and look for a URL in the decoded result. * Stop the search after the first match. - */ - char *url_segment = NULL; - /* + * * XXX: This estimate is guaranteed to be high enough as we * let ssplit() ignore empty fields, but also a bit wasteful. */ - size_t max_segments = strlen(subject) / 2; - char **url_segments = malloc(max_segments * sizeof(char *)); - int segments; + 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", new_url); + log_error(LOG_LEVEL_ERROR, + "Out of memory while decoding URL: %s", subject); freez(subject); return NULL; } - segments = ssplit(subject, "?&", url_segments, max_segments, 1, 1); + segments = ssplit(subject, "?&", url_segments, max_segments); while (segments-- > 0) { @@ -1131,14 +1115,8 @@ char *get_last_url(char *subject, const char *redirect_mode) } if (NULL != url_segment) { - url_segment = strdup(url_segment); + url_segment = strdup_or_die(url_segment); freez(dtoken); - if (url_segment == NULL) - { - log_error(LOG_LEVEL_ERROR, - "Out of memory while searching for redirects."); - return NULL; - } break; } freez(dtoken); @@ -1174,10 +1152,10 @@ char *get_last_url(char *subject, const char *redirect_mode) } if ((new_url != NULL) - && ( (new_url != subject) + && ( (new_url != subject) || (0 == strncmpic(subject, "http://", 7)) || (0 == strncmpic(subject, "https://", 8)) - )) + )) { /* * Return new URL if we found a redirect @@ -1238,11 +1216,14 @@ struct http_response *redirect_url(struct client_state *csp) * properly formatted URL and use it for the redirection * directly. * - * According to RFC 2616 section 14.30 the URL - * has to be absolute and if the user tries: - * +redirect{shit/this/will/be/parsed/as/pcrs_command.html} + * 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') @@ -1321,8 +1302,8 @@ struct http_response *redirect_url(struct client_state *csp) return cgi_error_memory(); } - if (enlist_unique_header(rsp->headers, "Location", new_url) - || (NULL == (rsp->status = strdup("302 Local Redirect from Privoxy")))) + 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); @@ -1410,7 +1391,7 @@ int is_untrusted_url(const struct client_state *csp) { struct file_list *fl; struct block_spec *b; - struct url_spec **trusted_url; + struct pattern_spec **trusted_url; struct http_request rhttp[1]; const char * referer; jb_err err; @@ -1467,12 +1448,12 @@ int is_untrusted_url(const struct client_state *csp) { char * path; char * path_end; - char * new_entry = strdup("~"); + char * new_entry = strdup_or_die("~"); string_append(&new_entry, csp->http->hostport); path = csp->http->path; - if ((path[0] == '/') + if ( (path[0] == '/') && (path[1] == '~') && ((path_end = strchr(path + 2, '/')) != NULL)) { @@ -1526,6 +1507,66 @@ int is_untrusted_url(const struct client_state *csp) #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 @@ -1544,14 +1585,12 @@ int is_untrusted_url(const struct client_state *csp) static char *pcrs_filter_response(struct client_state *csp) { int hits = 0; - int i; size_t size, prev_size; char *old = NULL; char *new = NULL; pcrs_job *job; - struct file_list *fl; struct re_filterfile_spec *b; struct list_entry *filtername; @@ -1573,108 +1612,87 @@ static char *pcrs_filter_response(struct client_state *csp) size = (size_t)(csp->iob->eod - csp->iob->cur); old = csp->iob->cur; - 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 all applying +filter actions, look if a filter by that * name exists and if yes, execute it's pcrs_joblist on the * buffer. */ - for (b = fl->f; b; b = b->next) + for (filtername = csp->action->multi[ACTION_MULTI_FILTER]->first; + filtername != NULL; filtername = filtername->next) { - if (b->type != FT_CONTENT_FILTER) + 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) { - /* Skip header filters */ continue; } - for (filtername = csp->action->multi[ACTION_MULTI_FILTER]->first; - filtername ; filtername = filtername->next) - { - if (strcmp(b->name, filtername->str) == 0) - { - 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->joblist; + joblist = b->joblist; - if (b->dynamic) joblist = compile_dynamic_pcrs_job_list(csp, b); + 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; - } + 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); + 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 (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); + if (b->dynamic) pcrs_free_joblist(joblist); - log_error(LOG_LEVEL_RE_FILTER, - "filtering %s%s (size %d) with \'%s\' produced %d hits (new size %d).", - csp->http->hostport, csp->http->path, prev_size, b->name, current_hits, size); + log_error(LOG_LEVEL_RE_FILTER, + "filtering %s%s (size %d) with \'%s\' produced %d hits (new size %d).", + csp->http->hostport, csp->http->path, prev_size, b->name, current_hits, size); - hits += current_hits; - } - } - } + hits += current_hits; } /* @@ -1689,13 +1707,239 @@ static char *pcrs_filter_response(struct client_state *csp) csp->flags |= CSP_FLAG_MODIFIED; csp->content_length = size; - IOB_RESET(csp); + 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 }, + }; + + 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(..., %d, 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 %d of up to %d 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 @@ -1719,12 +1963,8 @@ static char *gif_deanimate_response(struct client_state *csp) size = (size_t)(csp->iob->eod - csp->iob->cur); - if ( (NULL == (in = (struct binbuffer *)zalloc(sizeof *in))) - || (NULL == (out = (struct binbuffer *)zalloc(sizeof *out)))) - { - log_error(LOG_LEVEL_DEANIMATE, "failed! (no mem)"); - return NULL; - } + in = zalloc_or_die(sizeof(*in)); + out = zalloc_or_die(sizeof(*out)); in->buffer = csp->iob->cur; in->size = size; @@ -1762,7 +2002,8 @@ static char *gif_deanimate_response(struct client_state *csp) * Function : get_filter_function * * Description : Decides which content filter function has - * to be applied (if any). + * to be applied (if any). Only considers functions + * for internal filters which are mutually-exclusive. * * Parameters : * 1 : csp = Current client state (buffers, headers, etc...) @@ -1780,12 +2021,11 @@ static filter_function_ptr get_filter_function(const struct client_state *csp) * the content type and action settings. */ if ((csp->content_type & CT_TEXT) && - (csp->rlist != NULL) && (!list_is_empty(csp->action->multi[ACTION_MULTI_FILTER]))) { filter_function = pcrs_filter_response; } - else if ((csp->content_type & CT_GIF) && + else if ((csp->content_type & CT_GIF) && (csp->action->flags & ACTION_DEANIMATE)) { filter_function = gif_deanimate_response; @@ -1800,7 +2040,8 @@ static filter_function_ptr get_filter_function(const struct client_state *csp) * Function : remove_chunked_transfer_coding * * Description : In-situ remove the "chunked" transfer coding as defined - * in rfc2616 from a buffer. + * 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 @@ -1817,6 +2058,7 @@ static jb_err remove_chunked_transfer_coding(char *buffer, size_t *size) size_t newsize = 0; unsigned int chunksize = 0; char *from_p, *to_p; + const char *end_of_buffer = buffer + *size; assert(buffer); from_p = to_p = buffer; @@ -1829,27 +2071,62 @@ static jb_err remove_chunked_transfer_coding(char *buffer, size_t *size) 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 %u of %u buffered bytes.", + chunksize, (unsigned int)newsize, (unsigned int)*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; - if (chunksize >= *size - newsize) + /* + * 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, - "Chunk size %u exceeds buffered data left. " - "Already digested %u of %u buffered bytes.", - chunksize, (unsigned int)newsize, (unsigned int)*size); + "End of chunk is beyond the end of the buffer."); return JB_ERR_PARSE; } - newsize += chunksize; - from_p += 2; memmove(to_p, from_p, (size_t) chunksize); + newsize += chunksize; to_p = buffer + newsize; - from_p += chunksize + 2; + 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."); @@ -1957,6 +2234,7 @@ static jb_err prepare_for_filtering(struct client_state *csp) *********************************************************************/ char *execute_content_filters(struct client_state *csp) { + char *content; filter_function_ptr content_filter; assert(content_filters_enabled(csp->action)); @@ -1987,8 +2265,41 @@ char *execute_content_filters(struct client_state *csp) } 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; - return ((*content_filter)(csp)); } @@ -2020,13 +2331,16 @@ void get_url_actions(struct client_state *csp, struct http_request *http) 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 @@ -2036,14 +2350,18 @@ void get_url_actions(struct client_state *csp, struct http_request *http) * Parameters : * 1 : action = Destination. * 2 : http = Current URL - * 3 : b = list of URL actions to apply + * 3 : client_tags = list of client tags + * 4 : b = list of URL actions to apply * * Returns : N/A * *********************************************************************/ -void apply_url_actions(struct current_action_spec *action, - struct http_request *http, - struct url_actions *b) +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) { @@ -2057,6 +2375,12 @@ void apply_url_actions(struct current_action_spec *action, { 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 } } @@ -2087,7 +2411,7 @@ void apply_url_actions(struct current_action_spec *action, * Invalid syntax is fatal. * *********************************************************************/ -const static struct forward_spec *get_forward_override_settings(struct client_state *csp) +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]; @@ -2118,16 +2442,9 @@ const static struct forward_spec *get_forward_override_settings(struct client_st * the lifetime of this request. Save its location * in csp as well, so sweep() can free it later on. */ - fwd = csp->fwd = zalloc(sizeof(*fwd)); - if (NULL == fwd) - { - log_error(LOG_LEVEL_FATAL, - "can't allocate memory for forward-override{%s}", forward_override_line); - /* Never get here - LOG_LEVEL_FATAL causes program exit */ - return NULL; - } + fwd = csp->fwd = zalloc_or_die(sizeof(*fwd)); - vec_count = ssplit(forward_settings, " \t", vec, SZ(vec), 1, 1); + vec_count = ssplit(forward_settings, " \t", vec, SZ(vec)); if ((vec_count == 2) && !strcasecmp(vec[0], "forward")) { fwd->type = SOCKS_NONE; @@ -2135,6 +2452,14 @@ const static struct forward_spec *get_forward_override_settings(struct client_st /* 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) { @@ -2155,6 +2480,11 @@ const static struct forward_spec *get_forward_override_settings(struct client_st 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) { @@ -2207,7 +2537,7 @@ const static struct forward_spec *get_forward_override_settings(struct client_st const struct forward_spec *forward_url(struct client_state *csp, const struct http_request *http) { - static const struct forward_spec fwd_default[1] = { FORWARD_SPEC_INITIALIZER }; + 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) @@ -2285,12 +2615,7 @@ struct http_response *direct_response(struct client_state *csp) return cgi_error_memory(); } - if (NULL == (rsp->status = strdup("501 Not Implemented"))) - { - free_http_response(rsp); - return cgi_error_memory(); - } - + rsp->status = strdup_or_die("501 Not Implemented"); rsp->is_static = 1; rsp->crunch_reason = UNSUPPORTED; @@ -2362,8 +2687,8 @@ int content_requires_filtering(struct client_state *csp) * the content type and action settings. */ if ((csp->content_type & CT_TEXT) && - (csp->rlist != NULL) && - (!list_is_empty(csp->action->multi[ACTION_MULTI_FILTER]))) + (!list_is_empty(csp->action->multi[ACTION_MULTI_FILTER]) || + !list_is_empty(csp->action->multi[ACTION_MULTI_EXTERNAL_FILTER]))) { return TRUE; } @@ -2394,7 +2719,8 @@ int content_requires_filtering(struct client_state *csp) 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_FILTER]) || + !list_is_empty(action->multi[ACTION_MULTI_EXTERNAL_FILTER])); }