/* ========================================================================= *
 *                                                                           *
 *                 The Apache Software License,  Version 1.1                 *
 *                                                                           *
 *          Copyright (c) 1999-2001 The Apache Software Foundation.          *
 *                           All rights reserved.                            *
 *                                                                           *
 * ========================================================================= *
 *                                                                           *
 * Redistribution and use in source and binary forms,  with or without modi- *
 * fication, are permitted provided that the following conditions are met:   *
 *                                                                           *
 * 1. Redistributions of source code  must retain the above copyright notice *
 *    notice, this list of conditions and the following disclaimer.          *
 *                                                                           *
 * 2. Redistributions  in binary  form  must  reproduce the  above copyright *
 *    notice,  this list of conditions  and the following  disclaimer in the *
 *    documentation and/or other materials provided with the distribution.   *
 *                                                                           *
 * 3. The end-user documentation  included with the redistribution,  if any, *
 *    must include the following acknowlegement:                             *
 *                                                                           *
 *       "This product includes  software developed  by the Apache  Software *
 *        Foundation <http://www.apache.org/>."                              *
 *                                                                           *
 *    Alternately, this acknowlegement may appear in the software itself, if *
 *    and wherever such third-party acknowlegements normally appear.         *
 *                                                                           *
 * 4. The names  "The  Jakarta  Project",  "Jk",  and  "Apache  Software     *
 *    Foundation"  must not be used  to endorse or promote  products derived *
 *    from this  software without  prior  written  permission.  For  written *
 *    permission, please contact <apache@apache.org>.                        *
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 * 5. Products derived from this software may not be called "Apache" nor may *
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 *    Apache Software Foundation.                                            *
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 * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESSED OR IMPLIED WARRANTIES *
 * INCLUDING, BUT NOT LIMITED TO,  THE IMPLIED WARRANTIES OF MERCHANTABILITY *
 * AND FITNESS FOR  A PARTICULAR PURPOSE  ARE DISCLAIMED.  IN NO EVENT SHALL *
 * THE APACHE  SOFTWARE  FOUNDATION OR  ITS CONTRIBUTORS  BE LIABLE  FOR ANY *
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 * DAMAGES (INCLUDING,  BUT NOT LIMITED TO,  PROCUREMENT OF SUBSTITUTE GOODS *
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 * ANY  WAY  OUT OF  THE  USE OF  THIS  SOFTWARE,  EVEN  IF  ADVISED  OF THE *
 * POSSIBILITY OF SUCH DAMAGE.                                               *
 *                                                                           *
 * ========================================================================= *
 *                                                                           *
 * This software  consists of voluntary  contributions made  by many indivi- *
 * duals on behalf of the  Apache Software Foundation.  For more information *
 * on the Apache Software Foundation, please see <http://www.apache.org/>.   *
 *                                                                           *
 * ========================================================================= */

/***************************************************************************
 * Description: URI to worker map object.                                  *
 * Maps can be                                                             *
 *                                                                         *
 * Exact Context -> /exact/uri=worker e.g. /examples/do*=ajp12             *
 * Context Based -> /context/*=worker e.g. /examples/*=ajp12               *
 * Context and suffix ->/context/*.suffix=worker e.g. /examples/*.jsp=ajp12*
 *                                                                         *
 * This lets us either partition the work among the web server and the     *
 * servlet container.                                                      *
 *                                                                         *
 * Author:      Gal Shachor <shachor@il.ibm.com>                           *
 * Version:     $Revision: 1.19 $                                           *
 ***************************************************************************/

#include "jk_pool.h"
#include "jk_util.h"
#include "jk_uri_worker_map.h"

#define MATCH_TYPE_EXACT    (0)
#define MATCH_TYPE_CONTEXT  (1)
#define MATCH_TYPE_SUFFIX   (2)
#define MATCH_TYPE_GENERAL_SUFFIX (3) /* match all URIs of the form *ext */
/* match all context path URIs with a path component suffix */
#define MATCH_TYPE_CONTEXT_PATH (4)

struct uri_worker_record {
    /* Original uri for logging */
    char *uri;

    /* Name of worker mapped */
    char *worker_name;

    /* Suffix of uri */
    char *suffix;

    /* Base context */
    char *context;
    
    /* char length of the context */
    unsigned ctxt_len;

    int match_type;
};
typedef struct uri_worker_record uri_worker_record_t;

struct jk_uri_worker_map {
    /* Memory Pool */
    jk_pool_t           p;
    jk_pool_atom_t      buf[SMALL_POOL_SIZE];

    /* Temp Pool */
    jk_pool_t tp; 
    jk_pool_atom_t tbuf[SMALL_POOL_SIZE];

    /* map URI->WORKER */
    uri_worker_record_t **maps;

    /* Map Number */
    unsigned            size;

    /* Map Capacity */
    unsigned            capacity;
};


/*
 * We are now in a security nightmare, it maybe that somebody sent 
 * us a uri that looks like /top-secret.jsp. and the web server will 
 * fumble and return the jsp content. 
 *
 * To solve that we will check for path info following the suffix, we 
 * will also check that the end of the uri is not ".suffix.",
 * ".suffix/", or ".suffix ".
 */
static int check_security_fraud(jk_uri_worker_map_t *uw_map, 
                                const char *uri, 
                                jk_logger_t *l)
{
    unsigned i;    

    for(i = 0 ; i < uw_map->size ; i++) {
        if(MATCH_TYPE_SUFFIX == uw_map->maps[i]->match_type) {
            char *suffix_start;
            for(suffix_start = strstr(uri, uw_map->maps[i]->suffix) ;
                suffix_start ;
                suffix_start = strstr(suffix_start + 1, uw_map->maps[i]->suffix)) {
                
                if('.' != *(suffix_start - 1)) {
                    continue;
                } else {
                    char *after_suffix = suffix_start + strlen(uw_map->maps[i]->suffix);
                
                    if((('.' == *after_suffix) || ('/' == *after_suffix) || (' ' == *after_suffix)) &&
                       (0 == strncmp(uw_map->maps[i]->context, uri, uw_map->maps[i]->ctxt_len))) {
                        /* 
                         * Security violation !!!
                         * this is a fraud.
                         */
                        return i;
                    }
                }
            }
        }
    }

    return -1;
}


int uri_worker_map_alloc(jk_uri_worker_map_t **uw_map,
                         jk_map_t *init_data,
                         jk_logger_t *l)
{
    jk_log(l, JK_LOG_DEBUG, 
           "Into jk_uri_worker_map_t::uri_worker_map_alloc\n");    

    if(init_data && uw_map) {
        return uri_worker_map_open(*uw_map = (jk_uri_worker_map_t *)malloc(sizeof(jk_uri_worker_map_t)),
                                   init_data,
                                   l);
    }

    jk_log(l, JK_LOG_ERROR, 
           "In jk_uri_worker_map_t::uri_worker_map_alloc, NULL parameters\n");    

    return JK_FALSE;
}

int uri_worker_map_free(jk_uri_worker_map_t **uw_map,
                        jk_logger_t *l)
{
    jk_log(l, JK_LOG_DEBUG, 
           "Into jk_uri_worker_map_t::uri_worker_map_free\n");    

    if(uw_map && *uw_map) {
        uri_worker_map_close(*uw_map, l);  
        free(*uw_map);
        *uw_map = NULL;
	return JK_TRUE;
    }
    else 
    	jk_log(l, JK_LOG_ERROR, 
           "In jk_uri_worker_map_t::uri_worker_map_free, NULL parameters\n");    

    return JK_FALSE;
}

/*
 * Ensure there will be memory in context info to store Context Bases
 */

#define UW_INC_SIZE 4   /* 4 URI->WORKER STEP */

static int uri_worker_map_realloc(jk_uri_worker_map_t *uw_map)
{
    if (uw_map->size == uw_map->capacity) {
        uri_worker_record_t **uwr;
        int  capacity = uw_map->capacity + UW_INC_SIZE;

        uwr = (uri_worker_record_t **)jk_pool_alloc(&uw_map->p, sizeof(uri_worker_record_t *) * capacity);

        if (! uwr)
            return JK_FALSE;

        if (uw_map->capacity && uw_map->maps)
            memcpy(uwr, uw_map->maps, sizeof(uri_worker_record_t *) * uw_map->capacity);

        uw_map->maps = uwr;
        uw_map->capacity = capacity;
    }

    return JK_TRUE;
}


int uri_worker_map_add(jk_uri_worker_map_t *uw_map, 
                       char *puri, 
                       char *pworker,
                       jk_logger_t *l)
{
    uri_worker_record_t *uwr;
    char                *uri;
    char                *worker;

    if (uri_worker_map_realloc(uw_map) == JK_FALSE)
        return JK_FALSE;

    uwr = (uri_worker_record_t *)jk_pool_alloc(&uw_map->p, sizeof(uri_worker_record_t));

    if (! uwr) {
        jk_log(l, JK_LOG_ERROR, "jk_uri_worker_map_t::uri_worker_map_add, can't alloc map entry\n");
        return JK_FALSE;
    }

    uri = jk_pool_strdup(&uw_map->p, puri);
    worker = jk_pool_strdup(&uw_map->p, pworker);

    if (!uri || ! worker) {
        jk_log(l, JK_LOG_ERROR, "jk_uri_worker_map_t::uri_worker_map_add, can't alloc uri/worker strings\n");
        return JK_FALSE;
    }

    if ('/' == uri[0]) {
        char *asterisk = strchr(uri, '*');

        if (asterisk) {
            uwr->uri = jk_pool_strdup(&uw_map->p, uri);

            if (!uwr->uri) {
                jk_log(l, JK_LOG_ERROR, "jk_uri_worker_map_t::uri_worker_map_add, can't alloc uri string\n");
                return JK_FALSE;
            }
            
            /*
             * Now, lets check that the pattern is /context/*.suffix
             * or /context/*
             * we need to have a '/' then a '*' and the a '.' or a
             * '/' then a '*'
             */
             asterisk--;
             if ('/' == asterisk[0]) {
                if ( 0 == strncmp("/*/",uri,3) ) {
                    /* general context path */
                    asterisk[1] = '\0';
                    uwr->worker_name = worker;
                    uwr->context = uri;
                    uwr->suffix  = asterisk + 2;
                    uwr->match_type = MATCH_TYPE_CONTEXT_PATH;
                    jk_log(l, JK_LOG_DEBUG,
                           "Into jk_uri_worker_map_t::uri_worker_map_open, "
                           "general context path rule %s*%s=%s was added\n",
                           uri, asterisk + 2, worker);
                } else if ('.' == asterisk[2]) {
                    /* suffix rule */
                    asterisk[1]      = 
                    asterisk[2]      = '\0';
                    uwr->worker_name = worker;
                    uwr->context     = uri;
                    uwr->suffix      = asterisk + 3;
                    uwr->match_type  = MATCH_TYPE_SUFFIX;
                    jk_log(l, JK_LOG_DEBUG,
                           "Into jk_uri_worker_map_t::uri_worker_map_open, "
			   "suffix rule %s.%s=%s was added\n",
                            uri, asterisk + 3, worker); 
		} else if ('\0' != asterisk[2]) {
		    /* general suffix rule */
		    asterisk[1] = '\0';
		    uwr->worker_name = worker;
		    uwr->context = uri;
		    uwr->suffix  = asterisk + 2;
		    uwr->match_type = MATCH_TYPE_GENERAL_SUFFIX;
		    jk_log(l, JK_LOG_DEBUG,
			   "Into jk_uri_worker_map_t::uri_worker_map_open, "
			   "general suffix rule %s*%s=%s was added\n",
			   uri, asterisk + 2, worker);
		} else {
		    /* context based */
		    asterisk[1]      = '\0';
		    uwr->worker_name = worker;
		    uwr->context     = uri;
		    uwr->suffix      = NULL;
		    uwr->match_type  = MATCH_TYPE_CONTEXT;
		    jk_log(l, JK_LOG_DEBUG,
			   "Into jk_uri_worker_map_t::uri_worker_map_open, "
			   "match rule %s=%s was added\n",
			   uri, worker);
                }
            } else {
                /* Something like : JkMount /servlets/exampl* ajp13 */
                uwr->uri         = uri;
                uwr->worker_name = worker;
                uwr->context     = uri;
                uwr->suffix      = NULL;
                uwr->match_type  = MATCH_TYPE_EXACT;
                jk_log(l, JK_LOG_DEBUG,
                       "Into jk_uri_worker_map_t::uri_worker_map_open, exact rule %s=%s was added\n",
                        uri, worker);
            }

        } else {
            /* Something like:  JkMount /login/j_security_check ajp13 */
            uwr->uri         = uri;
            uwr->worker_name = worker;
            uwr->context     = uri;
            uwr->suffix      = NULL;
            uwr->match_type  = MATCH_TYPE_EXACT;
            jk_log(l, JK_LOG_DEBUG,
                   "Into jk_uri_worker_map_t::uri_worker_map_open, exact rule %s=%s was added\n",
                    uri, worker);
        }
        uwr->ctxt_len = strlen(uwr->context);
    } else {
        /*
         * JFC: please check...
         * Not sure what to do, but I try to prevent problems.
         * I have fixed jk_mount_context() in apaches/mod_jk.c so we should
         * not arrive here when using Apache.
         */
        jk_log(l, JK_LOG_ERROR,
               "jk_uri_worker_map_t::uri_worker_map_add, invalid context %s\n",
               uri);
        return JK_FALSE;
    }

    uw_map->maps[uw_map->size] = uwr;
    uw_map->size++;

    return JK_TRUE;
}

int uri_worker_map_open(jk_uri_worker_map_t *uw_map,
                        jk_map_t *init_data,
                        jk_logger_t *l)
{
    int rc = JK_TRUE;

    jk_log(l, JK_LOG_DEBUG, "Into jk_uri_worker_map_t::uri_worker_map_open\n");

    uw_map->size     = 0;
    uw_map->capacity = 0;

    if (uw_map) {
        int sz;

        rc = JK_TRUE;
        jk_open_pool(&uw_map->p, 
                     uw_map->buf, 
                     sizeof(jk_pool_atom_t) * SMALL_POOL_SIZE);
        jk_open_pool(&uw_map->tp,
                     uw_map->tbuf,
                     sizeof(jk_pool_atom_t) * SMALL_POOL_SIZE);

        uw_map->size = 0;
        uw_map->maps = NULL;
        
        sz = map_size(init_data);

        jk_log(l, JK_LOG_DEBUG, "jk_uri_worker_map_t::uri_worker_map_open, rule map size is %d\n", sz);

        if (sz > 0) {
            int i;
            for(i = 0; i < sz ; i++) {
                if (uri_worker_map_add(uw_map, map_name_at(init_data, i), map_value_at(init_data, i), l) == JK_FALSE) {
                    rc = JK_FALSE;
                    break;
                }
            }

            if (i == sz) {
                jk_log(l, JK_LOG_DEBUG, "Into jk_uri_worker_map_t::uri_worker_map_open, there are %d rules\n", uw_map->size);    
            } else {
                jk_log(l, JK_LOG_ERROR, "jk_uri_worker_map_t::uri_worker_map_open, There was a parsing error\n");
                rc = JK_FALSE;
            }
        }       

        if (rc == JK_FALSE) {
            jk_log(l, JK_LOG_ERROR, "jk_uri_worker_map_t::uri_worker_map_open, there was an error, freing buf\n");
            jk_close_pool(&uw_map->p);
            jk_close_pool(&uw_map->tp);
        }
    }
    
    jk_log(l, JK_LOG_DEBUG, "jk_uri_worker_map_t::uri_worker_map_open, done\n");
    return rc;
}

/* returns the index of the last occurrence of the 'ch' character
   if ch=='\0' returns the length of the string str  */
int last_index_of(const char *str,char ch)
{
    const char *str_minus_one=str-1;
    const char *s=str+strlen(str);
    while(s!=str_minus_one && ch!=*s) {
	--s;
    }
    return (s-str);
}

int uri_worker_map_close(jk_uri_worker_map_t *uw_map,
                         jk_logger_t *l)
{
    jk_log(l, JK_LOG_DEBUG, 
           "Into jk_uri_worker_map_t::uri_worker_map_close\n"); 

    if(uw_map) {
        jk_close_pool(&uw_map->p);
        jk_close_pool(&uw_map->tp);
	return JK_TRUE;
    }

    jk_log(l, JK_LOG_ERROR, 
           "jk_uri_worker_map_t::uri_worker_map_close, NULL parameter\n"); 

    return JK_FALSE;
}

void jk_no2slash(char *name)
{
    char *d, *s;

    s = d = name;

#if defined(HAVE_UNC_PATHS) 
    /* Check for UNC names.  Leave leading two slashes. */
    if (s[0] == '/' && s[1] == '/')
        *d++ = *s++;
#endif

    while (*s) {
        if ((*d++ = *s) == '/') {
            do {
                ++s;
            } while (*s == '/');
        }
        else {
            ++s;
        }
    }
    *d = '\0';
}


char *map_uri_to_worker(jk_uri_worker_map_t *uw_map,
                        char *uri,
                        jk_logger_t *l)
{
    jk_log(l, JK_LOG_DEBUG, 
           "Into jk_uri_worker_map_t::map_uri_to_worker\n");    

    if(uw_map && uri && '/' == uri[0]) {
        unsigned i;
        unsigned best_match = -1;
        unsigned longest_match = 0;
        char *url_rewrite = strstr(uri, JK_PATH_SESSION_IDENTIFIER);
        
        if(url_rewrite) {
            *url_rewrite = '\0';
        }
        jk_no2slash(uri);

        jk_log(l, JK_LOG_DEBUG, "Attempting to map URI '%s'\n", uri);
        for(i = 0 ; i < uw_map->size ; i++) {
            uri_worker_record_t *uwr = uw_map->maps[i];

            if(uwr->ctxt_len < longest_match) {
                continue; /* can not be a best match anyway */
            }

            if(0 == strncmp(uwr->context, 
                            uri, 
                            uwr->ctxt_len)) {
                if(MATCH_TYPE_EXACT == uwr->match_type) {
                    if(strlen(uri) == uwr->ctxt_len) {
			jk_log(l,
			       JK_LOG_DEBUG,
			       "jk_uri_worker_map_t::map_uri_to_worker, "
			       "Found an exact match %s -> %s\n",
			       uwr->worker_name,
			       uwr->context );
                        return uwr->worker_name;
                    }
                } else if(MATCH_TYPE_CONTEXT == uwr->match_type) {
                    if(uwr->ctxt_len > longest_match) {
			jk_log(l,
			       JK_LOG_DEBUG,
			       "jk_uri_worker_map_t::map_uri_to_worker, "
			       "Found a context match %s -> %s\n",
			       uwr->worker_name,
			       uwr->context );
                        longest_match = uwr->ctxt_len;
                        best_match = i;
                    }
		} else if(MATCH_TYPE_GENERAL_SUFFIX == uwr->match_type) {
                    int suffix_start=last_index_of(uri,uwr->suffix[0]);
                    if (suffix_start>=0 && 0==strcmp(uri+suffix_start,uwr->suffix)) {
			if(uwr->ctxt_len >= longest_match) {
			    jk_log(l,
				   JK_LOG_DEBUG,
				   "jk_uri_worker_map_t::map_uri_to_worker, "
				   "Found a general suffix match %s -> *%s\n",
				   uwr->worker_name,
				   uwr->suffix );
			    longest_match = uwr->ctxt_len;
			    best_match = i;
			}
                    }
                } else if(MATCH_TYPE_CONTEXT_PATH == uwr->match_type) {
                    char *suffix_path = NULL;
                    if (strlen(uri) > 1 && (suffix_path = strchr(uri+1,'/')) != NULL) {
                        if (0 == strncmp(suffix_path,uwr->suffix,strlen(uwr->suffix))) {
                            if(uwr->ctxt_len >= longest_match) {
                                jk_log(l,
                                       JK_LOG_DEBUG,
                                       "jk_uri_worker_map_t::map_uri_to_worker, "
                                       "Found a general context path match %s -> *%s\n",
                                       uwr->worker_name,
                                       uwr->suffix );   
                                longest_match = uwr->ctxt_len;
                                best_match = i;
                            }
                        }
                    }
                } else /* suffix match */ {
                    int suffix_start;
                    
                    for(suffix_start = strlen(uri) - 1 ; 
                        suffix_start > 0 && '.' != uri[suffix_start]; 
                        suffix_start--) 
                        ;
                    if('.' == uri[suffix_start]) {
                        const char *suffix = uri + suffix_start + 1;

                        /* for WinXX, fix the JsP != jsp problems */
#ifdef WIN32                        
                        if(0 == strcasecmp(suffix, uwr->suffix))  {
#else
                        if(0 == strcmp(suffix, uwr->suffix)) {
#endif
                            if(uwr->ctxt_len >= longest_match) {
				jk_log(l,
				       JK_LOG_DEBUG,
				       "jk_uri_worker_map_t::map_uri_to_worker, Found a suffix match %s -> *.%s\n",
				       uwr->worker_name,
				       uwr->suffix );
                                longest_match = uwr->ctxt_len;
                                best_match = i;
                            }
                        }
                    }                                       
                }
            }
        }

        if(-1 != best_match) {
            return uw_map->maps[best_match]->worker_name;
        } else {
            /*
             * We are now in a security nightmare, it maybe that somebody sent 
             * us a uri that looks like /top-secret.jsp. and the web server will 
             * fumble and return the jsp content. 
             *
             * To solve that we will check for path info following the suffix, we 
             * will also check that the end of the uri is not .suffix.
             */
            int fraud = check_security_fraud(uw_map, uri, l);

            if(fraud >= 0) {
                jk_log(l, JK_LOG_EMERG, 
                       "In jk_uri_worker_map_t::map_uri_to_worker, found a security fraud in '%s'\n",
                       uri);    
                return uw_map->maps[fraud]->worker_name;
            }
       }        
    } else {
        jk_log(l, JK_LOG_ERROR, 
               "In jk_uri_worker_map_t::map_uri_to_worker, wrong parameters\n");    
    }

    jk_log(l, JK_LOG_DEBUG, 
           "jk_uri_worker_map_t::map_uri_to_worker, done without a match\n"); 

    return NULL;
}