diff options
Diffstat (limited to 'rubbos/app/httpd-2.0.64/modules/metadata/mod_headers.c')
| -rw-r--r-- | rubbos/app/httpd-2.0.64/modules/metadata/mod_headers.c | 620 |
1 files changed, 620 insertions, 0 deletions
diff --git a/rubbos/app/httpd-2.0.64/modules/metadata/mod_headers.c b/rubbos/app/httpd-2.0.64/modules/metadata/mod_headers.c new file mode 100644 index 00000000..ce4460d4 --- /dev/null +++ b/rubbos/app/httpd-2.0.64/modules/metadata/mod_headers.c @@ -0,0 +1,620 @@ +/* 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. + */ + +/* + * mod_headers.c: Add/append/remove HTTP response headers + * Written by Paul Sutton, paul@ukweb.com, 1 Oct 1996 + * + * The Header directive can be used to add/replace/remove HTTP headers + * within the response message. The RequestHeader directive can be used + * to add/replace/remove HTTP headers before a request message is processed. + * Valid in both per-server and per-dir configurations. + * + * Syntax is: + * + * Header action header value + * RequestHeader action header value + * + * Where action is one of: + * set - set this header, replacing any old value + * add - add this header, possible resulting in two or more + * headers with the same name + * append - append this text onto any existing header of this same + * unset - remove this header + * + * Where action is unset, the third argument (value) should not be given. + * The header name can include the colon, or not. + * + * The Header and RequestHeader directives can only be used where allowed + * by the FileInfo override. + * + * When the request is processed, the header directives are processed in + * this order: firstly, the main server, then the virtual server handling + * this request (if any), then any <Directory> sections (working downwards + * from the root dir), then an <Location> sections (working down from + * shortest URL component), the any <File> sections. This order is + * important if any 'set' or 'unset' actions are used. For example, + * the following two directives have different effect if applied in + * the reverse order: + * + * Header append Author "John P. Doe" + * Header unset Author + * + * Examples: + * + * To set the "Author" header, use + * Header add Author "John P. Doe" + * + * To remove a header: + * Header unset Author + * + */ + +#include "apr.h" +#include "apr_lib.h" +#include "apr_strings.h" +#include "apr_buckets.h" + +#include "apr_hash.h" +#define APR_WANT_STRFUNC +#include "apr_want.h" + +#include "httpd.h" +#include "http_config.h" +#include "http_request.h" +#include "http_log.h" +#include "util_filter.h" +#include "http_protocol.h" /* ap_hook_insert_error_filter */ + +/* format_tag_hash is initialized during pre-config */ +static apr_hash_t *format_tag_hash; + +typedef enum { + hdr_add = 'a', /* add header (could mean multiple hdrs) */ + hdr_set = 's', /* set (replace old value) */ + hdr_append = 'm', /* append (merge into any old value) */ + hdr_unset = 'u', /* unset header */ + hdr_echo = 'e' /* echo headers from request to response */ +} hdr_actions; + +/* + * magic cmd->info values + */ +static char hdr_in = '0'; /* RequestHeader */ +static char hdr_out = '1'; /* Header onsuccess */ +static char hdr_err = '2'; /* Header always */ + +/* + * There is an array of struct format_tag per Header/RequestHeader + * config directive + */ +typedef struct { + const char* (*func)(request_rec *r,char *arg); + char *arg; +} format_tag; + +/* + * There is one "header_entry" per Header/RequestHeader config directive + */ +typedef struct { + hdr_actions action; + char *header; + apr_array_header_t *ta; /* Array of format_tag structs */ + regex_t *regex; + const char *condition_var; +} header_entry; + +/* echo_do is used for Header echo to iterate through the request headers*/ +typedef struct { + request_rec *r; + header_entry *hdr; +} echo_do; + +/* + * headers_conf is our per-module configuration. This is used as both + * a per-dir and per-server config + */ +typedef struct { + apr_array_header_t *fixup_in; + apr_array_header_t *fixup_out; + apr_array_header_t *fixup_err; +} headers_conf; + +module AP_MODULE_DECLARE_DATA headers_module; + +/* + * Tag formatting functions + */ +static const char *constant_item(request_rec *r, char *stuff) +{ + return stuff; +} +static const char *header_request_duration(request_rec *r, char *a) +{ + return apr_psprintf(r->pool, "D=%" APR_TIME_T_FMT, + (apr_time_now() - r->request_time)); +} +static const char *header_request_time(request_rec *r, char *a) +{ + return apr_psprintf(r->pool, "t=%" APR_TIME_T_FMT, r->request_time); +} +static const char *header_request_env_var(request_rec *r, char *a) +{ + const char *s = apr_table_get(r->subprocess_env,a); + + if (s) + return s; + else + return "(null)"; +} +/* + * Config routines + */ +static void *create_headers_config(apr_pool_t *p, char *dummy) +{ + headers_conf *conf = apr_palloc(p, sizeof(*conf)); + + conf->fixup_in = apr_array_make(p, 2, sizeof(header_entry)); + conf->fixup_out = apr_array_make(p, 2, sizeof(header_entry)); + conf->fixup_err = apr_array_make(p, 2, sizeof(header_entry)); + + return conf; +} + +static void *merge_headers_config(apr_pool_t *p, void *basev, void *overridesv) +{ + headers_conf *newconf = apr_palloc(p, sizeof(*newconf)); + headers_conf *base = basev; + headers_conf *overrides = overridesv; + + newconf->fixup_in = apr_array_append(p, base->fixup_in, overrides->fixup_in); + newconf->fixup_out = apr_array_append(p, base->fixup_out, overrides->fixup_out); + newconf->fixup_err = apr_array_append(p, base->fixup_err, overrides->fixup_err); + + return newconf; +} + +static char *parse_misc_string(apr_pool_t *p, format_tag *tag, const char **sa) +{ + const char *s; + char *d; + + tag->func = constant_item; + + s = *sa; + while (*s && *s != '%') { + s++; + } + /* + * This might allocate a few chars extra if there's a backslash + * escape in the format string. + */ + tag->arg = apr_palloc(p, s - *sa + 1); + + d = tag->arg; + s = *sa; + while (*s && *s != '%') { + if (*s != '\\') { + *d++ = *s++; + } + else { + s++; + switch (*s) { + case '\\': + *d++ = '\\'; + s++; + break; + case 'r': + *d++ = '\r'; + s++; + break; + case 'n': + *d++ = '\n'; + s++; + break; + case 't': + *d++ = '\t'; + s++; + break; + default: + /* copy verbatim */ + *d++ = '\\'; + /* + * Allow the loop to deal with this *s in the normal + * fashion so that it handles end of string etc. + * properly. + */ + break; + } + } + } + *d = '\0'; + + *sa = s; + return NULL; +} + +static char *parse_format_tag(apr_pool_t *p, format_tag *tag, const char **sa) +{ + const char *s = *sa; + const char * (*tag_handler)(request_rec *,char *); + + /* Handle string literal/conditionals */ + if (*s != '%') { + return parse_misc_string(p, tag, sa); + } + s++; /* skip the % */ + tag->arg = '\0'; + /* grab the argument if there is one */ + if (*s == '{') { + ++s; + tag->arg = ap_getword(p,&s,'}'); + } + + tag_handler = (const char * (*)(request_rec *,char *))apr_hash_get(format_tag_hash, s++, 1); + + if (!tag_handler) { + char dummy[2]; + dummy[0] = s[-1]; + dummy[1] = '\0'; + return apr_pstrcat(p, "Unrecognized Header or RequestHeader directive %", + dummy, NULL); + } + tag->func = tag_handler; + + *sa = s; + return NULL; +} + +/* + * A format string consists of white space, text and optional format + * tags in any order. E.g., + * + * Header add MyHeader "Free form text %D %t more text" + * + * Decompose the format string into its tags. Each tag (struct format_tag) + * contains a pointer to the function used to format the tag. Then save each + * tag in the tag array anchored in the header_entry. + */ +static char *parse_format_string(apr_pool_t *p, header_entry *hdr, const char *s) +{ + char *res; + + /* No string to parse with unset and copy commands */ + if (hdr->action == hdr_unset || + hdr->action == hdr_echo) { + return NULL; + } + + hdr->ta = apr_array_make(p, 10, sizeof(format_tag)); + + while (*s) { + if ((res = parse_format_tag(p, (format_tag *) apr_array_push(hdr->ta), &s))) { + return res; + } + } + return NULL; +} + +/* handle RequestHeader and Header directive */ +static const char *header_inout_cmd(cmd_parms *cmd, void *indirconf, + const char *action, const char *inhdr, + const char *value, const char* envclause) +{ + headers_conf *dirconf = indirconf; + const char *condition_var = NULL; + char *colon; + char *hdr = apr_pstrdup(cmd->pool, inhdr); + header_entry *new; + apr_array_header_t *fixup = (cmd->info == &hdr_in) + ? dirconf->fixup_in : (cmd->info == &hdr_err) + ? dirconf->fixup_err + : dirconf->fixup_out; + + new = (header_entry *) apr_array_push(fixup); + + if (!strcasecmp(action, "set")) + new->action = hdr_set; + else if (!strcasecmp(action, "add")) + new->action = hdr_add; + else if (!strcasecmp(action, "append")) + new->action = hdr_append; + else if (!strcasecmp(action, "unset")) + new->action = hdr_unset; + else if (!strcasecmp(action, "echo")) + new->action = hdr_echo; + else + return "first argument must be add, set, append, unset or echo."; + + if (new->action == hdr_unset) { + if (value) + return "header unset takes two arguments"; + } + else if (new->action == hdr_echo) { + regex_t *regex; + if (value) + return "Header echo takes two arguments"; + else if (cmd->info == &hdr_in) + return "Header echo only valid on Header directive"; + else { + regex = ap_pregcomp(cmd->pool, hdr, REG_EXTENDED | REG_NOSUB); + if (regex == NULL) { + return "Header echo regex could not be compiled"; + } + } + new->regex = regex; + } + else if (!value) + return "header requires three arguments"; + + /* Handle the envclause on Header */ + if (envclause != NULL) { + if (strncasecmp(envclause, "env=", 4) != 0) { + return "error: envclause should be in the form env=envar"; + } + if ((envclause[4] == '\0') + || ((envclause[4] == '!') && (envclause[5] == '\0'))) { + return "error: missing environment variable name. envclause should be in the form env=envar "; + } + condition_var = apr_pstrdup(cmd->pool, &envclause[4]); + } + + if ((colon = strchr(hdr, ':'))) + *colon = '\0'; + + new->header = hdr; + new->condition_var = condition_var; + + return parse_format_string(cmd->pool, new, value); +} + +/* Handle all (xxx)Header directives */ +static const char *header_cmd(cmd_parms *cmd, void *indirconf, + const char *args) +{ + const char *s; + const char *action; + const char *hdr; + const char *val; + const char *envclause; + + s = apr_pstrdup(cmd->pool, args); + action = ap_getword_conf(cmd->pool, &s); + if (cmd->info == &hdr_out) { + if (!strcasecmp(action, "always")) { + cmd->info = &hdr_err; + action = ap_getword_conf(cmd->pool, &s); + } + else if (!strcasecmp(action, "onsuccess")) { + action = ap_getword_conf(cmd->pool, &s); + } + } + hdr = ap_getword_conf(cmd->pool, &s); + val = *s ? ap_getword_conf(cmd->pool, &s) : NULL; + envclause = *s ? ap_getword_conf(cmd->pool, &s) : NULL; + + if (*s) { + return apr_pstrcat(cmd->pool, cmd->cmd->name, + " has too many arguments", NULL); + } + + return header_inout_cmd(cmd, indirconf, action, hdr, val, envclause); +} + +/* + * Process the tags in the format string. Tags may be format specifiers + * (%D, %t, etc.), whitespace or text strings. For each tag, run the handler + * (formatter) specific to the tag. Handlers return text strings. + * Concatenate the return from each handler into one string that is + * returned from this call. + */ +static char* process_tags(header_entry *hdr, request_rec *r) +{ + int i; + const char *s; + char *str = NULL; + + format_tag *tag = (format_tag*) hdr->ta->elts; + + for (i = 0; i < hdr->ta->nelts; i++) { + s = tag[i].func(r, tag[i].arg); + if (str == NULL) + str = apr_pstrdup(r->pool, s); + else + str = apr_pstrcat(r->pool, str, s, NULL); + } + return str ? str : ""; +} + +static int echo_header(echo_do *v, const char *key, const char *val) +{ + /* If the input header (key) matches the regex, echo it intact to + * r->headers_out. + */ + if (!ap_regexec(v->hdr->regex, key, 0, NULL, 0)) { + apr_table_add(v->r->headers_out, key, val); + } + + return 1; +} + +static void do_headers_fixup(request_rec *r, apr_table_t *headers, + apr_array_header_t *fixup) +{ + int i; + + for (i = 0; i < fixup->nelts; ++i) { + header_entry *hdr = &((header_entry *) (fixup->elts))[i]; + + /* Have any conditional envar-controlled Header processing to do? */ + if (hdr->condition_var) { + const char *envar = hdr->condition_var; + if (*envar != '!') { + if (apr_table_get(r->subprocess_env, envar) == NULL) + continue; + } + else { + if (apr_table_get(r->subprocess_env, &envar[1]) != NULL) + continue; + } + } + + switch (hdr->action) { + case hdr_add: + apr_table_addn(headers, hdr->header, process_tags(hdr, r)); + break; + case hdr_append: + apr_table_mergen(headers, hdr->header, process_tags(hdr, r)); + break; + case hdr_set: + apr_table_setn(headers, hdr->header, process_tags(hdr, r)); + break; + case hdr_unset: + apr_table_unset(headers, hdr->header); + break; + case hdr_echo: + { + echo_do v; + v.r = r; + v.hdr = hdr; + apr_table_do((int (*) (void *, const char *, const char *)) + echo_header, (void *) &v, r->headers_in, NULL); + break; + } + } + } +} + +static void ap_headers_insert_output_filter(request_rec *r) +{ + headers_conf *dirconf = ap_get_module_config(r->per_dir_config, + &headers_module); + + if (dirconf->fixup_out->nelts || dirconf->fixup_err->nelts) { + ap_add_output_filter("FIXUP_HEADERS_OUT", NULL, r, r->connection); + } +} + +static void ap_headers_insert_error_filter(request_rec *r) +{ + headers_conf *dirconf = ap_get_module_config(r->per_dir_config, + &headers_module); + + if (dirconf->fixup_err->nelts) { + ap_add_output_filter("FIXUP_HEADERS_ERR", NULL, r, r->connection); + } +} + +static apr_status_t ap_headers_output_filter(ap_filter_t *f, + apr_bucket_brigade *in) +{ + headers_conf *dirconf = ap_get_module_config(f->r->per_dir_config, + &headers_module); + + ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, f->r->server, + "headers: ap_headers_output_filter()"); + + /* do the fixup */ + do_headers_fixup(f->r, f->r->err_headers_out, dirconf->fixup_err); + do_headers_fixup(f->r, f->r->headers_out, dirconf->fixup_out); + + /* remove ourselves from the filter chain */ + ap_remove_output_filter(f); + + /* send the data up the stack */ + return ap_pass_brigade(f->next,in); +} + +static apr_status_t ap_headers_error_filter(ap_filter_t *f, + apr_bucket_brigade *in) +{ + headers_conf *dirconf = ap_get_module_config(f->r->per_dir_config, + &headers_module); + + ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, f->r->server, + "headers: ap_headers_error_filter()"); + + /* do the fixup */ + do_headers_fixup(f->r, f->r->err_headers_out, dirconf->fixup_err); + + /* remove ourselves from the filter chain */ + ap_remove_output_filter(f); + + /* send the data up the stack */ + return ap_pass_brigade(f->next,in); +} + +static apr_status_t ap_headers_fixup(request_rec *r) +{ + headers_conf *dirconf = ap_get_module_config(r->per_dir_config, + &headers_module); + + /* do the fixup */ + if (dirconf->fixup_in->nelts) { + do_headers_fixup(r, r->headers_in, dirconf->fixup_in); + } + + return DECLINED; +} + +static const command_rec headers_cmds[] = +{ + AP_INIT_RAW_ARGS("Header", header_cmd, &hdr_out, OR_FILEINFO, + "an optional condition, an action, header and value " + "followed by optional env clause"), + AP_INIT_RAW_ARGS("RequestHeader", header_cmd, &hdr_in, OR_FILEINFO, + "an action, header and value"), + {NULL} +}; + +static void register_format_tag_handler(apr_pool_t *p, char *tag, void *tag_handler, int def) +{ + const void *h = apr_palloc(p, sizeof(h)); + h = tag_handler; + apr_hash_set(format_tag_hash, tag, 1, h); +} +static int header_pre_config(apr_pool_t *p, apr_pool_t *plog, apr_pool_t *ptemp) +{ + format_tag_hash = apr_hash_make(p); + register_format_tag_handler(p, "D", (void*) header_request_duration, 0); + register_format_tag_handler(p, "t", (void*) header_request_time, 0); + register_format_tag_handler(p, "e", (void*) header_request_env_var, 0); + + return OK; +} + +static void register_hooks(apr_pool_t *p) +{ + ap_hook_pre_config(header_pre_config,NULL,NULL,APR_HOOK_MIDDLE); + ap_hook_insert_filter(ap_headers_insert_output_filter, NULL, NULL, APR_HOOK_LAST); + ap_hook_insert_error_filter(ap_headers_insert_error_filter, NULL, NULL, APR_HOOK_LAST); + ap_hook_fixups(ap_headers_fixup, NULL, NULL, APR_HOOK_LAST); + ap_register_output_filter("FIXUP_HEADERS_OUT", ap_headers_output_filter, + NULL, AP_FTYPE_CONTENT_SET); + ap_register_output_filter("FIXUP_HEADERS_ERR", ap_headers_error_filter, + NULL, AP_FTYPE_CONTENT_SET); +} + +module AP_MODULE_DECLARE_DATA headers_module = +{ + STANDARD20_MODULE_STUFF, + create_headers_config, /* dir config creater */ + merge_headers_config, /* dir merger --- default is to override */ + NULL, /* server config */ + NULL, /* merge server configs */ + headers_cmds, /* command apr_table_t */ + register_hooks /* register hooks */ +}; |