| /* Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #define APR_WANT_STRFUNC |
| #include "apr_want.h" |
| #include "apr_lib.h" |
| #include "apr_hash.h" |
| #include "apr_strings.h" |
| |
| #include "httpd.h" |
| #include "http_config.h" |
| #include "http_core.h" |
| #include "http_log.h" |
| #include "util_filter.h" |
| |
| /* NOTE: Apache's current design doesn't allow a pool to be passed thru, |
| so we depend on a global to hold the correct pool |
| */ |
| #define FILTER_POOL apr_hook_global_pool |
| #include "ap_hooks.h" /* for apr_hook_global_pool */ |
| |
| /* |
| ** This macro returns true/false if a given filter should be inserted BEFORE |
| ** another filter. This will happen when one of: 1) there isn't another |
| ** filter; 2) that filter has a higher filter type (class); 3) that filter |
| ** corresponds to a different request. |
| */ |
| #define INSERT_BEFORE(f, before_this) ((before_this) == NULL \ |
| || (before_this)->frec->ftype > (f)->frec->ftype \ |
| || (before_this)->r != (f)->r) |
| |
| /* Trie structure to hold the mapping from registered |
| * filter names to filters |
| */ |
| |
| /* we know core's module_index is 0 */ |
| #undef APLOG_MODULE_INDEX |
| #define APLOG_MODULE_INDEX AP_CORE_MODULE_INDEX |
| |
| typedef struct filter_trie_node filter_trie_node; |
| |
| typedef struct { |
| int c; |
| filter_trie_node *child; |
| } filter_trie_child_ptr; |
| |
| /* Each trie node has an array of pointers to its children. |
| * The array is kept in sorted order so that add_any_filter() |
| * can do a binary search |
| */ |
| struct filter_trie_node { |
| ap_filter_rec_t *frec; |
| filter_trie_child_ptr *children; |
| int nchildren; |
| int size; |
| }; |
| |
| #define TRIE_INITIAL_SIZE 4 |
| |
| /* Link a trie node to its parent |
| */ |
| static void trie_node_link(apr_pool_t *p, filter_trie_node *parent, |
| filter_trie_node *child, int c) |
| { |
| int i, j; |
| |
| if (parent->nchildren == parent->size) { |
| filter_trie_child_ptr *new; |
| parent->size *= 2; |
| new = (filter_trie_child_ptr *)apr_palloc(p, parent->size * |
| sizeof(filter_trie_child_ptr)); |
| memcpy(new, parent->children, parent->nchildren * |
| sizeof(filter_trie_child_ptr)); |
| parent->children = new; |
| } |
| |
| for (i = 0; i < parent->nchildren; i++) { |
| if (c == parent->children[i].c) { |
| return; |
| } |
| else if (c < parent->children[i].c) { |
| break; |
| } |
| } |
| for (j = parent->nchildren; j > i; j--) { |
| parent->children[j].c = parent->children[j - 1].c; |
| parent->children[j].child = parent->children[j - 1].child; |
| } |
| parent->children[i].c = c; |
| parent->children[i].child = child; |
| |
| parent->nchildren++; |
| } |
| |
| /* Allocate a new node for a trie. |
| * If parent is non-NULL, link the new node under the parent node with |
| * key 'c' (or, if an existing child node matches, return that one) |
| */ |
| static filter_trie_node *trie_node_alloc(apr_pool_t *p, |
| filter_trie_node *parent, char c) |
| { |
| filter_trie_node *new_node; |
| if (parent) { |
| int i; |
| for (i = 0; i < parent->nchildren; i++) { |
| if (c == parent->children[i].c) { |
| return parent->children[i].child; |
| } |
| else if (c < parent->children[i].c) { |
| break; |
| } |
| } |
| new_node = |
| (filter_trie_node *)apr_palloc(p, sizeof(filter_trie_node)); |
| trie_node_link(p, parent, new_node, c); |
| } |
| else { /* No parent node */ |
| new_node = (filter_trie_node *)apr_palloc(p, |
| sizeof(filter_trie_node)); |
| } |
| |
| new_node->frec = NULL; |
| new_node->nchildren = 0; |
| new_node->size = TRIE_INITIAL_SIZE; |
| new_node->children = (filter_trie_child_ptr *)apr_palloc(p, |
| new_node->size * sizeof(filter_trie_child_ptr)); |
| return new_node; |
| } |
| |
| static filter_trie_node *registered_output_filters = NULL; |
| static filter_trie_node *registered_input_filters = NULL; |
| |
| |
| static apr_status_t filter_cleanup(void *ctx) |
| { |
| registered_output_filters = NULL; |
| registered_input_filters = NULL; |
| return APR_SUCCESS; |
| } |
| |
| static ap_filter_rec_t *get_filter_handle(const char *name, |
| const filter_trie_node *filter_set) |
| { |
| if (filter_set) { |
| const char *n; |
| const filter_trie_node *node; |
| |
| node = filter_set; |
| for (n = name; *n; n++) { |
| int start, end; |
| start = 0; |
| end = node->nchildren - 1; |
| while (end >= start) { |
| int middle = (end + start) / 2; |
| char ch = node->children[middle].c; |
| if (*n == ch) { |
| node = node->children[middle].child; |
| break; |
| } |
| else if (*n < ch) { |
| end = middle - 1; |
| } |
| else { |
| start = middle + 1; |
| } |
| } |
| if (end < start) { |
| node = NULL; |
| break; |
| } |
| } |
| |
| if (node && node->frec) { |
| return node->frec; |
| } |
| } |
| return NULL; |
| } |
| |
| AP_DECLARE(ap_filter_rec_t *)ap_get_output_filter_handle(const char *name) |
| { |
| return get_filter_handle(name, registered_output_filters); |
| } |
| |
| AP_DECLARE(ap_filter_rec_t *)ap_get_input_filter_handle(const char *name) |
| { |
| return get_filter_handle(name, registered_input_filters); |
| } |
| |
| static ap_filter_rec_t *register_filter(const char *name, |
| ap_filter_func filter_func, |
| ap_init_filter_func filter_init, |
| ap_filter_type ftype, |
| filter_trie_node **reg_filter_set) |
| { |
| ap_filter_rec_t *frec; |
| char *normalized_name; |
| const char *n; |
| filter_trie_node *node; |
| |
| if (!*reg_filter_set) { |
| *reg_filter_set = trie_node_alloc(FILTER_POOL, NULL, 0); |
| } |
| |
| normalized_name = apr_pstrdup(FILTER_POOL, name); |
| ap_str_tolower(normalized_name); |
| |
| node = *reg_filter_set; |
| for (n = normalized_name; *n; n++) { |
| filter_trie_node *child = trie_node_alloc(FILTER_POOL, node, *n); |
| if (apr_isalpha(*n)) { |
| trie_node_link(FILTER_POOL, node, child, apr_toupper(*n)); |
| } |
| node = child; |
| } |
| if (node->frec) { |
| frec = node->frec; |
| } |
| else { |
| frec = apr_pcalloc(FILTER_POOL, sizeof(*frec)); |
| node->frec = frec; |
| frec->name = normalized_name; |
| } |
| frec->filter_func = filter_func; |
| frec->filter_init_func = filter_init; |
| frec->ftype = ftype; |
| |
| apr_pool_cleanup_register(FILTER_POOL, NULL, filter_cleanup, |
| apr_pool_cleanup_null); |
| return frec; |
| } |
| |
| AP_DECLARE(ap_filter_rec_t *) ap_register_input_filter(const char *name, |
| ap_in_filter_func filter_func, |
| ap_init_filter_func filter_init, |
| ap_filter_type ftype) |
| { |
| ap_filter_func f; |
| f.in_func = filter_func; |
| return register_filter(name, f, filter_init, ftype, |
| ®istered_input_filters); |
| } |
| |
| AP_DECLARE(ap_filter_rec_t *) ap_register_output_filter(const char *name, |
| ap_out_filter_func filter_func, |
| ap_init_filter_func filter_init, |
| ap_filter_type ftype) |
| { |
| return ap_register_output_filter_protocol(name, filter_func, |
| filter_init, ftype, 0); |
| } |
| |
| AP_DECLARE(ap_filter_rec_t *) ap_register_output_filter_protocol( |
| const char *name, |
| ap_out_filter_func filter_func, |
| ap_init_filter_func filter_init, |
| ap_filter_type ftype, |
| unsigned int proto_flags) |
| { |
| ap_filter_rec_t* ret ; |
| ap_filter_func f; |
| f.out_func = filter_func; |
| ret = register_filter(name, f, filter_init, ftype, |
| ®istered_output_filters); |
| ret->proto_flags = proto_flags ; |
| return ret ; |
| } |
| |
| static ap_filter_t *add_any_filter_handle(ap_filter_rec_t *frec, void *ctx, |
| request_rec *r, conn_rec *c, |
| ap_filter_t **r_filters, |
| ap_filter_t **p_filters, |
| ap_filter_t **c_filters) |
| { |
| apr_pool_t *p = frec->ftype < AP_FTYPE_CONNECTION && r ? r->pool : c->pool; |
| ap_filter_t *f = apr_palloc(p, sizeof(*f)); |
| ap_filter_t **outf; |
| |
| if (frec->ftype < AP_FTYPE_PROTOCOL) { |
| if (r) { |
| outf = r_filters; |
| } |
| else { |
| ap_log_cerror(APLOG_MARK, APLOG_ERR, 0, c, APLOGNO(00080) |
| "a content filter was added without a request: %s", frec->name); |
| return NULL; |
| } |
| } |
| else if (frec->ftype < AP_FTYPE_CONNECTION) { |
| if (r) { |
| outf = p_filters; |
| } |
| else { |
| ap_log_cerror(APLOG_MARK, APLOG_ERR, 0, c, APLOGNO(00081) |
| "a protocol filter was added without a request: %s", frec->name); |
| return NULL; |
| } |
| } |
| else { |
| outf = c_filters; |
| } |
| |
| f->frec = frec; |
| f->ctx = ctx; |
| /* f->r must always be NULL for connection filters */ |
| f->r = frec->ftype < AP_FTYPE_CONNECTION ? r : NULL; |
| f->c = c; |
| f->next = NULL; |
| |
| if (INSERT_BEFORE(f, *outf)) { |
| f->next = *outf; |
| |
| if (*outf) { |
| ap_filter_t *first = NULL; |
| |
| if (r) { |
| /* If we are adding our first non-connection filter, |
| * Then don't try to find the right location, it is |
| * automatically first. |
| */ |
| if (*r_filters != *c_filters) { |
| first = *r_filters; |
| while (first && (first->next != (*outf))) { |
| first = first->next; |
| } |
| } |
| } |
| if (first && first != (*outf)) { |
| first->next = f; |
| } |
| } |
| *outf = f; |
| } |
| else { |
| ap_filter_t *fscan = *outf; |
| while (!INSERT_BEFORE(f, fscan->next)) |
| fscan = fscan->next; |
| |
| f->next = fscan->next; |
| fscan->next = f; |
| } |
| |
| if (frec->ftype < AP_FTYPE_CONNECTION && (*r_filters == *c_filters)) { |
| *r_filters = *p_filters; |
| } |
| return f; |
| } |
| |
| static ap_filter_t *add_any_filter(const char *name, void *ctx, |
| request_rec *r, conn_rec *c, |
| const filter_trie_node *reg_filter_set, |
| ap_filter_t **r_filters, |
| ap_filter_t **p_filters, |
| ap_filter_t **c_filters) |
| { |
| if (reg_filter_set) { |
| const char *n; |
| const filter_trie_node *node; |
| |
| node = reg_filter_set; |
| for (n = name; *n; n++) { |
| int start, end; |
| start = 0; |
| end = node->nchildren - 1; |
| while (end >= start) { |
| int middle = (end + start) / 2; |
| char ch = node->children[middle].c; |
| if (*n == ch) { |
| node = node->children[middle].child; |
| break; |
| } |
| else if (*n < ch) { |
| end = middle - 1; |
| } |
| else { |
| start = middle + 1; |
| } |
| } |
| if (end < start) { |
| node = NULL; |
| break; |
| } |
| } |
| |
| if (node && node->frec) { |
| return add_any_filter_handle(node->frec, ctx, r, c, r_filters, |
| p_filters, c_filters); |
| } |
| } |
| |
| ap_log_cerror(APLOG_MARK, APLOG_ERR, 0, r ? r->connection : c, APLOGNO(00082) |
| "an unknown filter was not added: %s", name); |
| return NULL; |
| } |
| |
| AP_DECLARE(ap_filter_t *) ap_add_input_filter(const char *name, void *ctx, |
| request_rec *r, conn_rec *c) |
| { |
| return add_any_filter(name, ctx, r, c, registered_input_filters, |
| r ? &r->input_filters : NULL, |
| r ? &r->proto_input_filters : NULL, &c->input_filters); |
| } |
| |
| AP_DECLARE(ap_filter_t *) ap_add_input_filter_handle(ap_filter_rec_t *f, |
| void *ctx, |
| request_rec *r, |
| conn_rec *c) |
| { |
| return add_any_filter_handle(f, ctx, r, c, r ? &r->input_filters : NULL, |
| r ? &r->proto_input_filters : NULL, |
| &c->input_filters); |
| } |
| |
| AP_DECLARE(ap_filter_t *) ap_add_output_filter(const char *name, void *ctx, |
| request_rec *r, conn_rec *c) |
| { |
| return add_any_filter(name, ctx, r, c, registered_output_filters, |
| r ? &r->output_filters : NULL, |
| r ? &r->proto_output_filters : NULL, &c->output_filters); |
| } |
| |
| AP_DECLARE(ap_filter_t *) ap_add_output_filter_handle(ap_filter_rec_t *f, |
| void *ctx, |
| request_rec *r, |
| conn_rec *c) |
| { |
| return add_any_filter_handle(f, ctx, r, c, r ? &r->output_filters : NULL, |
| r ? &r->proto_output_filters : NULL, |
| &c->output_filters); |
| } |
| |
| static void remove_any_filter(ap_filter_t *f, ap_filter_t **r_filt, ap_filter_t **p_filt, |
| ap_filter_t **c_filt) |
| { |
| ap_filter_t **curr = r_filt ? r_filt : c_filt; |
| ap_filter_t *fscan = *curr; |
| |
| if (p_filt && *p_filt == f) |
| *p_filt = (*p_filt)->next; |
| |
| if (*curr == f) { |
| *curr = (*curr)->next; |
| return; |
| } |
| |
| while (fscan->next != f) { |
| if (!(fscan = fscan->next)) { |
| return; |
| } |
| } |
| |
| fscan->next = f->next; |
| } |
| |
| AP_DECLARE(void) ap_remove_input_filter(ap_filter_t *f) |
| { |
| remove_any_filter(f, f->r ? &f->r->input_filters : NULL, |
| f->r ? &f->r->proto_input_filters : NULL, |
| &f->c->input_filters); |
| } |
| |
| AP_DECLARE(void) ap_remove_output_filter(ap_filter_t *f) |
| { |
| remove_any_filter(f, f->r ? &f->r->output_filters : NULL, |
| f->r ? &f->r->proto_output_filters : NULL, |
| &f->c->output_filters); |
| } |
| |
| AP_DECLARE(apr_status_t) ap_remove_input_filter_byhandle(ap_filter_t *next, |
| const char *handle) |
| { |
| ap_filter_t *found = NULL; |
| ap_filter_rec_t *filter; |
| |
| if (!handle) { |
| return APR_EINVAL; |
| } |
| filter = ap_get_input_filter_handle(handle); |
| if (!filter) { |
| return APR_NOTFOUND; |
| } |
| |
| while (next) { |
| if (next->frec == filter) { |
| found = next; |
| break; |
| } |
| next = next->next; |
| } |
| if (found) { |
| ap_remove_input_filter(found); |
| return APR_SUCCESS; |
| } |
| return APR_NOTFOUND; |
| } |
| |
| AP_DECLARE(apr_status_t) ap_remove_output_filter_byhandle(ap_filter_t *next, |
| const char *handle) |
| { |
| ap_filter_t *found = NULL; |
| ap_filter_rec_t *filter; |
| |
| if (!handle) { |
| return APR_EINVAL; |
| } |
| filter = ap_get_output_filter_handle(handle); |
| if (!filter) { |
| return APR_NOTFOUND; |
| } |
| |
| while (next) { |
| if (next->frec == filter) { |
| found = next; |
| break; |
| } |
| next = next->next; |
| } |
| if (found) { |
| ap_remove_output_filter(found); |
| return APR_SUCCESS; |
| } |
| return APR_NOTFOUND; |
| } |
| |
| |
| /* |
| * Read data from the next filter in the filter stack. Data should be |
| * modified in the bucket brigade that is passed in. The core allocates the |
| * bucket brigade, modules that wish to replace large chunks of data or to |
| * save data off to the side should probably create their own temporary |
| * brigade especially for that use. |
| */ |
| AP_DECLARE(apr_status_t) ap_get_brigade(ap_filter_t *next, |
| apr_bucket_brigade *bb, |
| ap_input_mode_t mode, |
| apr_read_type_e block, |
| apr_off_t readbytes) |
| { |
| if (next) { |
| return next->frec->filter_func.in_func(next, bb, mode, block, |
| readbytes); |
| } |
| return AP_NOBODY_READ; |
| } |
| |
| /* Pass the buckets to the next filter in the filter stack. If the |
| * current filter is a handler, we should get NULL passed in instead of |
| * the current filter. At that point, we can just call the first filter in |
| * the stack, or r->output_filters. |
| */ |
| AP_DECLARE(apr_status_t) ap_pass_brigade(ap_filter_t *next, |
| apr_bucket_brigade *bb) |
| { |
| if (next) { |
| apr_bucket *e; |
| if ((e = APR_BRIGADE_LAST(bb)) && APR_BUCKET_IS_EOS(e) && next->r) { |
| /* This is only safe because HTTP_HEADER filter is always in |
| * the filter stack. This ensures that there is ALWAYS a |
| * request-based filter that we can attach this to. If the |
| * HTTP_FILTER is removed, and another filter is not put in its |
| * place, then handlers like mod_cgi, which attach their own |
| * EOS bucket to the brigade will be broken, because we will |
| * get two EOS buckets on the same request. |
| */ |
| next->r->eos_sent = 1; |
| |
| /* remember the eos for internal redirects, too */ |
| if (next->r->prev) { |
| request_rec *prev = next->r->prev; |
| |
| while (prev) { |
| prev->eos_sent = 1; |
| prev = prev->prev; |
| } |
| } |
| } |
| return next->frec->filter_func.out_func(next, bb); |
| } |
| return AP_NOBODY_WROTE; |
| } |
| |
| /* Pass the buckets to the next filter in the filter stack |
| * checking return status for filter errors. |
| * returns: OK if ap_pass_brigade returns APR_SUCCESS |
| * AP_FILTER_ERROR if filter error exists |
| * HTTP_INTERNAL_SERVER_ERROR for all other cases |
| * logged with optional errmsg |
| */ |
| AP_DECLARE(apr_status_t) ap_pass_brigade_fchk(request_rec *r, |
| apr_bucket_brigade *bb, |
| const char *fmt, |
| ...) |
| { |
| apr_status_t rv; |
| |
| rv = ap_pass_brigade(r->output_filters, bb); |
| if (rv != APR_SUCCESS) { |
| if (rv != AP_FILTER_ERROR) { |
| if (!fmt) |
| ap_log_rerror(APLOG_MARK, APLOG_DEBUG, rv, r, APLOGNO(00083) |
| "ap_pass_brigade returned %d", rv); |
| else { |
| va_list ap; |
| const char *res; |
| va_start(ap, fmt); |
| res = apr_pvsprintf(r->pool, fmt, ap); |
| va_end(ap); |
| ap_log_rerror(APLOG_MARK, APLOG_DEBUG, rv, r, APLOGNO(03158) |
| "%s", res); |
| } |
| return HTTP_INTERNAL_SERVER_ERROR; |
| } |
| return AP_FILTER_ERROR; |
| } |
| return OK; |
| } |
| |
| AP_DECLARE(apr_status_t) ap_save_brigade(ap_filter_t *f, |
| apr_bucket_brigade **saveto, |
| apr_bucket_brigade **b, apr_pool_t *p) |
| { |
| apr_bucket *e; |
| apr_status_t rv, srv = APR_SUCCESS; |
| |
| /* If have never stored any data in the filter, then we had better |
| * create an empty bucket brigade so that we can concat. |
| */ |
| if (!(*saveto)) { |
| *saveto = apr_brigade_create(p, f->c->bucket_alloc); |
| } |
| |
| for (e = APR_BRIGADE_FIRST(*b); |
| e != APR_BRIGADE_SENTINEL(*b); |
| e = APR_BUCKET_NEXT(e)) |
| { |
| rv = apr_bucket_setaside(e, p); |
| |
| /* If the bucket type does not implement setaside, then |
| * (hopefully) morph it into a bucket type which does, and set |
| * *that* aside... */ |
| if (rv == APR_ENOTIMPL) { |
| const char *s; |
| apr_size_t n; |
| |
| rv = apr_bucket_read(e, &s, &n, APR_BLOCK_READ); |
| if (rv == APR_SUCCESS) { |
| rv = apr_bucket_setaside(e, p); |
| } |
| } |
| |
| if (rv != APR_SUCCESS) { |
| srv = rv; |
| /* Return an error but still save the brigade if |
| * ->setaside() is really not implemented. */ |
| if (rv != APR_ENOTIMPL) { |
| return rv; |
| } |
| } |
| } |
| APR_BRIGADE_CONCAT(*saveto, *b); |
| return srv; |
| } |
| |
| AP_DECLARE_NONSTD(apr_status_t) ap_filter_flush(apr_bucket_brigade *bb, |
| void *ctx) |
| { |
| ap_filter_t *f = ctx; |
| apr_status_t rv; |
| |
| rv = ap_pass_brigade(f, bb); |
| |
| /* Before invocation of the flush callback, apr_brigade_write et |
| * al may place transient buckets in the brigade, which will fall |
| * out of scope after returning. Empty the brigade here, to avoid |
| * issues with leaving such buckets in the brigade if some filter |
| * fails and leaves a non-empty brigade. */ |
| apr_brigade_cleanup(bb); |
| |
| return rv; |
| } |
| |
| AP_DECLARE(apr_status_t) ap_fflush(ap_filter_t *f, apr_bucket_brigade *bb) |
| { |
| apr_bucket *b; |
| |
| b = apr_bucket_flush_create(f->c->bucket_alloc); |
| APR_BRIGADE_INSERT_TAIL(bb, b); |
| return ap_pass_brigade(f, bb); |
| } |
| |
| AP_DECLARE_NONSTD(apr_status_t) ap_fputstrs(ap_filter_t *f, |
| apr_bucket_brigade *bb, ...) |
| { |
| va_list args; |
| apr_status_t rv; |
| |
| va_start(args, bb); |
| rv = apr_brigade_vputstrs(bb, ap_filter_flush, f, args); |
| va_end(args); |
| return rv; |
| } |
| |
| AP_DECLARE_NONSTD(apr_status_t) ap_fprintf(ap_filter_t *f, |
| apr_bucket_brigade *bb, |
| const char *fmt, |
| ...) |
| { |
| va_list args; |
| apr_status_t rv; |
| |
| va_start(args, fmt); |
| rv = apr_brigade_vprintf(bb, ap_filter_flush, f, fmt, args); |
| va_end(args); |
| return rv; |
| } |
| AP_DECLARE(void) ap_filter_protocol(ap_filter_t *f, unsigned int flags) |
| { |
| f->frec->proto_flags = flags ; |
| } |