Adding upstream version 2.4.38.upstream/2.4.38upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 658 insertions, 0 deletions

diff --git a/modules/metadata/mod_setenvif.c b/modules/metadata/mod_setenvif.c
new file mode 100644
index 0000000..23d60cd
--- /dev/null
+++ b/modules/metadata/mod_setenvif.c
@@ -0,0 +1,658 @@
+/* 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_setenvif.c
+ * Set environment variables based on matching request headers or
+ * attributes against regex strings
+ *
+ * Paul Sutton <paul@ukweb.com> 27 Oct 1996
+ * Based on mod_browser by Alexei Kosut <akosut@organic.com>
+ */
+
+/*
+ * Used to set environment variables based on the incoming request headers,
+ * or some selected other attributes of the request (e.g., the remote host
+ * name).
+ *
+ * Usage:
+ *
+ *   SetEnvIf name regex var ...
+ *
+ * where name is either a HTTP request header name, or one of the
+ * special values (see below). 'name' may be a regex when it is used
+ * to specify an HTTP request header name. The 'value' of the header
+ & (or the value of the special value from below) are compared against
+ * the regex argument. If this is a simple string, a simple sub-string
+ * match is performed. Otherwise, a request expression match is
+ * done. If the value matches the string or regular expression, the
+ * environment variables listed as var ... are set. Each var can
+ * be in one of three formats: var, which sets the named variable
+ * (the value "1"); var=value, which sets the variable to
+ * the given value; or !var, which unsets the variable is it has
+ * been previously set.
+ *
+ * Normally the strings are compared with regard to case. To ignore
+ * case, use the directive SetEnvIfNoCase instead.
+ *
+ * Special values for 'name' are:
+ *
+ *   server_addr        IP address of interface on which request arrived
+ *                      (analogous to SERVER_ADDR set in ap_add_common_vars())
+ *   remote_host        Remote host name (if available)
+ *   remote_addr        Remote IP address
+ *   request_method     Request method (GET, POST, etc)
+ *   request_uri        Requested URI
+ *
+ * Examples:
+ *
+ * To set the environment variable LOCALHOST if the client is the local
+ * machine:
+ *
+ *    SetEnvIf remote_addr 127.0.0.1 LOCALHOST
+ *
+ * To set LOCAL if the client is the local host, or within our company's
+ * domain (192.168.10):
+ *
+ *    SetEnvIf remote_addr 192.168.10. LOCAL
+ *    SetEnvIf remote_addr 127.0.0.1   LOCALHOST
+ *
+ * This could be written as:
+ *
+ *    SetEnvIf remote_addr (127.0.0.1|192.168.10.) LOCAL
+ *
+ * To set HAVE_TS if the client request contains any header beginning
+ * with "TS" with a value beginning with a lower case alphabet:
+ *
+ *    SetEnvIf ^TS* ^[a-z].* HAVE_TS
+ */
+
+#include "apr.h"
+#include "apr_strings.h"
+#include "apr_strmatch.h"
+
+#define APR_WANT_STRFUNC
+#include "apr_want.h"
+
+#include "ap_config.h"
+#include "httpd.h"
+#include "http_config.h"
+#include "http_core.h"
+#include "http_log.h"
+#include "http_protocol.h"
+
+enum special {
+    SPECIAL_NOT,
+    SPECIAL_REMOTE_ADDR,
+    SPECIAL_REMOTE_HOST,
+    SPECIAL_REQUEST_URI,
+    SPECIAL_REQUEST_METHOD,
+    SPECIAL_REQUEST_PROTOCOL,
+    SPECIAL_SERVER_ADDR
+};
+typedef struct {
+    char *name;                 /* header name */
+    ap_regex_t *pnamereg;       /* compiled header name regex */
+    char *regex;                /* regex to match against */
+    ap_regex_t *preg;           /* compiled regex */
+    const apr_strmatch_pattern *pattern; /* non-regex pattern to match */
+    ap_expr_info_t *expr;       /* parsed expression */
+    apr_table_t *features;      /* env vars to set (or unset) */
+    enum special special_type;  /* is it a "special" header ? */
+    int icase;                  /* ignoring case? */
+} sei_entry;
+
+typedef struct {
+    apr_array_header_t *conditionals;
+} sei_cfg_rec;
+
+module AP_MODULE_DECLARE_DATA setenvif_module;
+
+/*
+ * These routines, the create- and merge-config functions, are called
+ * for both the server-wide and the per-directory contexts.  This is
+ * because the different definitions are used at different times; the
+ * server-wide ones are used in the post-read-request phase, and the
+ * per-directory ones are used during the header-parse phase (after
+ * the URI has been mapped to a file and we have anything from the
+ * .htaccess file and <Directory> and <Files> containers).
+ */
+static void *create_setenvif_config(apr_pool_t *p)
+{
+    sei_cfg_rec *new = (sei_cfg_rec *) apr_palloc(p, sizeof(sei_cfg_rec));
+
+    new->conditionals = apr_array_make(p, 20, sizeof(sei_entry));
+    return (void *) new;
+}
+
+static void *create_setenvif_config_svr(apr_pool_t *p, server_rec *dummy)
+{
+    return create_setenvif_config(p);
+}
+
+static void *create_setenvif_config_dir(apr_pool_t *p, char *dummy)
+{
+    return create_setenvif_config(p);
+}
+
+static void *merge_setenvif_config(apr_pool_t *p, void *basev, void *overridesv)
+{
+    sei_cfg_rec *a = apr_pcalloc(p, sizeof(sei_cfg_rec));
+    sei_cfg_rec *base = basev, *overrides = overridesv;
+
+    a->conditionals = apr_array_append(p, base->conditionals,
+                                       overrides->conditionals);
+    return a;
+}
+
+/*
+ * any non-NULL magic constant will do... used to indicate if AP_REG_ICASE should
+ * be used
+ */
+#define ICASE_MAGIC  ((void *)(&setenvif_module))
+#define SEI_MAGIC_HEIRLOOM "setenvif-phase-flag"
+
+static ap_regex_t *is_header_regex_regex;
+
+static int is_header_regex(apr_pool_t *p, const char* name)
+{
+    /* If a Header name contains characters other than:
+     *    -,_,[A-Z\, [a-z] and [0-9].
+     * assume the header name is a regular expression.
+     */
+    if (ap_regexec(is_header_regex_regex, name, 0, NULL, 0)) {
+        return 1;
+    }
+
+    return 0;
+}
+
+/* If the input string does not take advantage of regular
+ * expression metacharacters, return a pointer to an equivalent
+ * string that can be searched using apr_strmatch().  (The
+ * returned string will often be the input string.  But if
+ * the input string contains escaped characters, the returned
+ * string will be a copy with the escapes removed.)
+ */
+static const char *non_regex_pattern(apr_pool_t *p, const char *s)
+{
+    const char *src = s;
+    int escapes_found = 0;
+    int in_escape = 0;
+
+    while (*src) {
+        switch (*src) {
+        case '^':
+        case '.':
+        case '$':
+        case '|':
+        case '(':
+        case ')':
+        case '[':
+        case ']':
+        case '*':
+        case '+':
+        case '?':
+        case '{':
+        case '}':
+            if (!in_escape) {
+                return NULL;
+            }
+            in_escape = 0;
+            break;
+        case '\\':
+            if (!in_escape) {
+                in_escape = 1;
+                escapes_found = 1;
+            }
+            else {
+                in_escape = 0;
+            }
+            break;
+        default:
+            if (in_escape) {
+                return NULL;
+            }
+            break;
+        }
+        src++;
+    }
+    if (!escapes_found) {
+        return s;
+    }
+    else {
+        char *unescaped = (char *)apr_palloc(p, src - s + 1);
+        char *dst = unescaped;
+        src = s;
+        do {
+            if (*src == '\\') {
+                src++;
+            }
+        } while ((*dst++ = *src++));
+        return unescaped;
+    }
+}
+
+static const char *add_envvars(cmd_parms *cmd, const char *args, sei_entry *new)
+{
+    const char *feature;
+    int beenhere = 0;
+    char *var;
+
+    for ( ; ; ) {
+        feature = ap_getword_conf(cmd->pool, &args);
+        if (!*feature) {
+            break;
+        }
+        beenhere++;
+
+        var = ap_getword(cmd->pool, &feature, '=');
+        if (*feature) {
+            apr_table_setn(new->features, var, feature);
+        }
+        else if (*var == '!') {
+            apr_table_setn(new->features, var + 1, "!");
+        }
+        else {
+            apr_table_setn(new->features, var, "1");
+        }
+    }
+
+    if (!beenhere) {
+        return apr_pstrcat(cmd->pool, "Missing envariable expression for ",
+                           cmd->cmd->name, NULL);
+    }
+
+    return NULL;
+}
+
+static const char *add_setenvif_core(cmd_parms *cmd, void *mconfig,
+                                     char *fname, const char *args)
+{
+    char *regex;
+    const char *simple_pattern;
+    sei_cfg_rec *sconf;
+    sei_entry *new;
+    sei_entry *entries;
+    int i;
+    int icase;
+
+    /*
+     * Determine from our context into which record to put the entry.
+     * cmd->path == NULL means we're in server-wide context; otherwise,
+     * we're dealing with a per-directory setting.
+     */
+    sconf = (cmd->path != NULL)
+      ? (sei_cfg_rec *) mconfig
+      : (sei_cfg_rec *) ap_get_module_config(cmd->server->module_config,
+                                               &setenvif_module);
+    entries = (sei_entry *) sconf->conditionals->elts;
+    /* get regex */
+    regex = ap_getword_conf(cmd->pool, &args);
+    if (!*regex) {
+        return apr_pstrcat(cmd->pool, "Missing regular expression for ",
+                           cmd->cmd->name, NULL);
+    }
+
+    /*
+     * If we've already got a sei_entry with the same name we want to
+     * just copy the name pointer... so that later on we can compare
+     * two header names just by comparing the pointers.
+     */
+    for (i = 0; i < sconf->conditionals->nelts; ++i) {
+        new = &entries[i];
+        if (new->name && !strcasecmp(new->name, fname)) {
+            fname = new->name;
+            break;
+        }
+    }
+
+    /* if the last entry has an identical headername and regex then
+     * merge with it
+     */
+    i = sconf->conditionals->nelts - 1;
+    icase = cmd->info == ICASE_MAGIC;
+    if (i < 0
+        || entries[i].name != fname
+        || entries[i].icase != icase
+        || strcmp(entries[i].regex, regex)) {
+
+        /* no match, create a new entry */
+        new = apr_array_push(sconf->conditionals);
+        new->name = fname;
+        new->regex = regex;
+        new->icase = icase;
+        if ((simple_pattern = non_regex_pattern(cmd->pool, regex))) {
+            new->pattern = apr_strmatch_precompile(cmd->pool,
+                                                   simple_pattern, !icase);
+            if (new->pattern == NULL) {
+                return apr_pstrcat(cmd->pool, cmd->cmd->name,
+                                   " pattern could not be compiled.", NULL);
+            }
+            new->preg = NULL;
+        }
+        else {
+            new->preg = ap_pregcomp(cmd->pool, regex,
+                                    (AP_REG_EXTENDED | (icase ? AP_REG_ICASE : 0)));
+            if (new->preg == NULL) {
+                return apr_pstrcat(cmd->pool, cmd->cmd->name,
+                                   " regex could not be compiled.", NULL);
+            }
+            new->pattern = NULL;
+        }
+        new->features = apr_table_make(cmd->pool, 2);
+
+        if (!strcasecmp(fname, "remote_addr")) {
+            new->special_type = SPECIAL_REMOTE_ADDR;
+        }
+        else if (!strcasecmp(fname, "remote_host")) {
+            new->special_type = SPECIAL_REMOTE_HOST;
+        }
+        else if (!strcasecmp(fname, "request_uri")) {
+            new->special_type = SPECIAL_REQUEST_URI;
+        }
+        else if (!strcasecmp(fname, "request_method")) {
+            new->special_type = SPECIAL_REQUEST_METHOD;
+        }
+        else if (!strcasecmp(fname, "request_protocol")) {
+            new->special_type = SPECIAL_REQUEST_PROTOCOL;
+        }
+        else if (!strcasecmp(fname, "server_addr")) {
+            new->special_type = SPECIAL_SERVER_ADDR;
+        }
+        else {
+            new->special_type = SPECIAL_NOT;
+            /* Handle fname as a regular expression.
+             * If fname a simple header string, identify as such
+             * (new->pnamereg = NULL) to avoid the overhead of searching
+             * through headers_in for a regex match.
+             */
+            if (is_header_regex(cmd->temp_pool, fname)) {
+                new->pnamereg = ap_pregcomp(cmd->pool, fname,
+                                            (AP_REG_EXTENDED | AP_REG_NOSUB
+                                             | (icase ? AP_REG_ICASE : 0)));
+                if (new->pnamereg == NULL)
+                    return apr_pstrcat(cmd->pool, cmd->cmd->name,
+                                       "Header name regex could not be "
+                                       "compiled.", NULL);
+            }
+            else {
+                new->pnamereg = NULL;
+            }
+        }
+    }
+    else {
+        new = &entries[i];
+    }
+
+    return add_envvars(cmd, args, new);
+}
+
+static const char *add_setenvif(cmd_parms *cmd, void *mconfig,
+                                const char *args)
+{
+    char *fname;
+
+    /* get header name */
+    fname = ap_getword_conf(cmd->pool, &args);
+    if (!*fname) {
+        return apr_pstrcat(cmd->pool, "Missing header-field name for ",
+                           cmd->cmd->name, NULL);
+    }
+    return add_setenvif_core(cmd, mconfig, fname, args);
+}
+
+static const char *add_setenvifexpr(cmd_parms *cmd, void *mconfig,
+                                    const char *args)
+{
+    char *expr;
+    sei_cfg_rec *sconf;
+    sei_entry *new;
+    const char *err;
+
+    /*
+     * Determine from our context into which record to put the entry.
+     * cmd->path == NULL means we're in server-wide context; otherwise,
+     * we're dealing with a per-directory setting.
+     */
+    sconf = (cmd->path != NULL)
+      ? (sei_cfg_rec *) mconfig
+      : (sei_cfg_rec *) ap_get_module_config(cmd->server->module_config,
+                                               &setenvif_module);
+    /* get expr */
+    expr = ap_getword_conf(cmd->pool, &args);
+    if (!*expr) {
+        return apr_pstrcat(cmd->pool, "Missing expression for ",
+                           cmd->cmd->name, NULL);
+    }
+
+    new = apr_array_push(sconf->conditionals);
+    new->features = apr_table_make(cmd->pool, 2);
+    new->name = NULL;
+    new->regex = NULL;
+    new->pattern = NULL;
+    new->preg = NULL;
+    new->expr = ap_expr_parse_cmd(cmd, expr, 0, &err, NULL);
+    if (err)
+        return apr_psprintf(cmd->pool, "Could not parse expression \"%s\": %s",
+                            expr, err);
+
+    return add_envvars(cmd, args, new);
+}
+
+/*
+ * This routine handles the BrowserMatch* directives.  It simply turns around
+ * and feeds them, with the appropriate embellishments, to the general-purpose
+ * command handler.
+ */
+static const char *add_browser(cmd_parms *cmd, void *mconfig, const char *args)
+{
+    return add_setenvif_core(cmd, mconfig, "User-Agent", args);
+}
+
+static const command_rec setenvif_module_cmds[] =
+{
+    AP_INIT_RAW_ARGS("SetEnvIf", add_setenvif, NULL, OR_FILEINFO,
+                     "A header-name, regex and a list of variables."),
+    AP_INIT_RAW_ARGS("SetEnvIfNoCase", add_setenvif, ICASE_MAGIC, OR_FILEINFO,
+                     "a header-name, regex and a list of variables."),
+    AP_INIT_RAW_ARGS("SetEnvIfExpr", add_setenvifexpr, NULL, OR_FILEINFO,
+                     "an expression and a list of variables."),
+    AP_INIT_RAW_ARGS("BrowserMatch", add_browser, NULL, OR_FILEINFO,
+                     "A browser regex and a list of variables."),
+    AP_INIT_RAW_ARGS("BrowserMatchNoCase", add_browser, ICASE_MAGIC,
+                     OR_FILEINFO,
+                     "A browser regex and a list of variables."),
+    { NULL },
+};
+
+/*
+ * This routine gets called at two different points in request processing:
+ * once before the URI has been translated (during the post-read-request
+ * phase) and once after (during the header-parse phase).  We use different
+ * config records for the two different calls to reduce overhead (by not
+ * re-doing the server-wide settings during directory processing), and
+ * signal which call it is by having the earlier one pass a flag to the
+ * later one.
+ */
+static int match_headers(request_rec *r)
+{
+    sei_cfg_rec *sconf;
+    sei_entry *entries;
+    const apr_table_entry_t *elts;
+    const char *val, *err;
+    apr_size_t val_len = 0;
+    int i, j;
+    char *last_name;
+    ap_regmatch_t regm[AP_MAX_REG_MATCH];
+
+    if (!ap_get_module_config(r->request_config, &setenvif_module)) {
+        ap_set_module_config(r->request_config, &setenvif_module,
+                             SEI_MAGIC_HEIRLOOM);
+        sconf  = (sei_cfg_rec *) ap_get_module_config(r->server->module_config,
+                                                      &setenvif_module);
+    }
+    else {
+        sconf = (sei_cfg_rec *) ap_get_module_config(r->per_dir_config,
+                                                     &setenvif_module);
+    }
+    entries = (sei_entry *) sconf->conditionals->elts;
+    last_name = NULL;
+    val = NULL;
+    for (i = 0; i < sconf->conditionals->nelts; ++i) {
+        sei_entry *b = &entries[i];
+
+        if (!b->expr) {
+            /* Optimize the case where a bunch of directives in a row use the
+             * same header.  Remember we don't need to strcmp the two header
+             * names because we made sure the pointers were equal during
+             * configuration.
+             */
+            if (b->name != last_name) {
+                last_name = b->name;
+                switch (b->special_type) {
+                case SPECIAL_REMOTE_ADDR:
+                    val = r->useragent_ip;
+                    break;
+                case SPECIAL_SERVER_ADDR:
+                    val = r->connection->local_ip;
+                    break;
+                case SPECIAL_REMOTE_HOST:
+                    val = ap_get_useragent_host(r, REMOTE_NAME, NULL);
+                    break;
+                case SPECIAL_REQUEST_URI:
+                    val = r->uri;
+                    break;
+                case SPECIAL_REQUEST_METHOD:
+                    val = r->method;
+                    break;
+                case SPECIAL_REQUEST_PROTOCOL:
+                    val = r->protocol;
+                    break;
+                case SPECIAL_NOT:
+                    if (b->pnamereg) {
+                        /* Matching headers_in against a regex. Iterate through
+                         * the headers_in until we find a match or run out of
+                         * headers.
+                         */
+                        const apr_array_header_t
+                            *arr = apr_table_elts(r->headers_in);
+
+                        elts = (const apr_table_entry_t *) arr->elts;
+                        val = NULL;
+                        for (j = 0; j < arr->nelts; ++j) {
+                            if (!ap_regexec(b->pnamereg, elts[j].key, 0, NULL, 0)) {
+                                val = elts[j].val;
+                            }
+                        }
+                    }
+                    else {
+                        /* Not matching against a regex */
+                        val = apr_table_get(r->headers_in, b->name);
+                        if (val == NULL) {
+                            val = apr_table_get(r->subprocess_env, b->name);
+                        }
+                    }
+                }
+                val_len = val ? strlen(val) : 0;
+            }
+
+        }
+
+        /*
+         * A NULL value indicates that the header field or special entity
+         * wasn't present or is undefined.  Represent that as an empty string
+         * so that REs like "^$" will work and allow envariable setting
+         * based on missing or empty field. This is also necessary to make
+         * ap_pregsub work after evaluating an ap_expr_t which does set the
+         * regexp backref data.
+         */
+        if (val == NULL) {
+            val = "";
+            val_len = 0;
+        }
+
+        if ((b->pattern && apr_strmatch(b->pattern, val, val_len)) ||
+            (b->preg && !ap_regexec(b->preg, val, AP_MAX_REG_MATCH, regm, 0)) ||
+            (b->expr && ap_expr_exec_re(r, b->expr, AP_MAX_REG_MATCH, regm, &val, &err) > 0))
+        {
+            const apr_array_header_t *arr = apr_table_elts(b->features);
+            elts = (const apr_table_entry_t *) arr->elts;
+
+            for (j = 0; j < arr->nelts; ++j) {
+                if (*(elts[j].val) == '!') {
+                    apr_table_unset(r->subprocess_env, elts[j].key);
+                }
+                else {
+                    /*
+                     * Do regex replacement, if we did not use a pattern, so
+                     * either a regex or an expression and if we have a val
+                     * or at least we did not use an expression.
+                     * Background: We can have expressions that become true
+                     * if a regex pattern in the expression does NOT match.
+                     * In this case val is NULL and we should just set the
+                     * value for the environment variable like in the pattern
+                     * case.
+                     */
+                    if (!b->pattern && (val || !b->expr)) {
+                        char *replaced = ap_pregsub(r->pool, elts[j].val, val,
+                                                    AP_MAX_REG_MATCH, regm);
+                        if (replaced) {
+                            apr_table_setn(r->subprocess_env, elts[j].key,
+                                           replaced);
+                        }
+                        else {
+                            ap_log_rerror(APLOG_MARK, APLOG_CRIT, 0, r, APLOGNO(01505)
+                                          "Regular expression replacement "
+                                          "failed for '%s', value too long?",
+                                          elts[j].key);
+                            return HTTP_INTERNAL_SERVER_ERROR;
+                        }
+                    }
+                    else {
+                        apr_table_setn(r->subprocess_env, elts[j].key,
+                                       elts[j].val);
+                    }
+                }
+                ap_log_rerror(APLOG_MARK, APLOG_TRACE2, 0, r, "Setting %s",
+                              elts[j].key);
+            }
+        }
+    }
+
+    return DECLINED;
+}
+
+static void register_hooks(apr_pool_t *p)
+{
+    ap_hook_header_parser(match_headers, NULL, NULL, APR_HOOK_MIDDLE);
+    ap_hook_post_read_request(match_headers, NULL, NULL, APR_HOOK_MIDDLE);
+
+    is_header_regex_regex = ap_pregcomp(p, "^[-A-Za-z0-9_]*$",
+                                        (AP_REG_EXTENDED | AP_REG_NOSUB ));
+    ap_assert(is_header_regex_regex != NULL);
+}
+
+AP_DECLARE_MODULE(setenvif) =
+{
+    STANDARD20_MODULE_STUFF,
+    create_setenvif_config_dir, /* dir config creater */
+    merge_setenvif_config,      /* dir merger --- default is to override */
+    create_setenvif_config_svr, /* server config */
+    merge_setenvif_config,      /* merge server configs */
+    setenvif_module_cmds,       /* command apr_table_t */
+    register_hooks              /* register hooks */
+};