proxy_util.c

来自「apache服务器源代码（版本号：2.2.2）」· C语言 代码 · 共 2,057 行 · 第 1/5 页

    char *host = This->name;
    const char *host2 = proxy_get_host_of_request(r);
    int h2_len;
    int h1_len;

    if (host == NULL || host2 == NULL)
        return 0; /* oops! */

    h2_len = strlen(host2);
    h1_len = strlen(host);

#if 0
    struct apr_sockaddr_t *addr = *This->hostaddr;

    /* Try to deal with multiple IP addr's for a host */
    while (addr) {
        if (addr->ipaddr_ptr == ? ? ? ? ? ? ? ? ? ? ? ? ?)
            return 1;
        addr = addr->next;
    }
#endif

    /* Ignore trailing dots in host2 comparison: */
    while (h2_len > 0 && host2[h2_len - 1] == '.')
        --h2_len;
    while (h1_len > 0 && host[h1_len - 1] == '.')
        --h1_len;
    return h1_len == h2_len
        && strncasecmp(host, host2, h1_len) == 0;
}

/* Return TRUE if addr is to be matched as a word */
PROXY_DECLARE(int) ap_proxy_is_word(struct dirconn_entry *This, apr_pool_t *p)
{
    This->matcher = proxy_match_word;
    return 1;
}

/* Return TRUE if string "str2" occurs literally in "str1" */
static int proxy_match_word(struct dirconn_entry *This, request_rec *r)
{
    const char *host = proxy_get_host_of_request(r);
    return host != NULL && ap_strstr_c(host, This->name) != NULL;
}

/* checks whether a host in uri_addr matches proxyblock */
PROXY_DECLARE(int) ap_proxy_checkproxyblock(request_rec *r, proxy_server_conf *conf,
                             apr_sockaddr_t *uri_addr)
{
    int j;
    apr_sockaddr_t * src_uri_addr = uri_addr;
    /* XXX FIXME: conf->noproxies->elts is part of an opaque structure */
    for (j = 0; j < conf->noproxies->nelts; j++) {
        struct noproxy_entry *npent = (struct noproxy_entry *) conf->noproxies->elts;
        struct apr_sockaddr_t *conf_addr = npent[j].addr;
        uri_addr = src_uri_addr;
        ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
                     "proxy: checking remote machine [%s] against [%s]", uri_addr->hostname, npent[j].name);
        if ((npent[j].name && ap_strstr_c(uri_addr->hostname, npent[j].name))
            || npent[j].name[0] == '*') {
            ap_log_error(APLOG_MARK, APLOG_WARNING, 0, r->server,
                         "proxy: connect to remote machine %s blocked: name %s matched", uri_addr->hostname, npent[j].name);
            return HTTP_FORBIDDEN;
        }
        while (conf_addr) {
            while (uri_addr) {
                char *conf_ip;
                char *uri_ip;
                apr_sockaddr_ip_get(&conf_ip, conf_addr);
                apr_sockaddr_ip_get(&uri_ip, uri_addr);
                ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
                             "proxy: ProxyBlock comparing %s and %s", conf_ip, uri_ip);
                if (!apr_strnatcasecmp(conf_ip, uri_ip)) {
                    ap_log_error(APLOG_MARK, APLOG_WARNING, 0, r->server,
                                 "proxy: connect to remote machine %s blocked: IP %s matched", uri_addr->hostname, conf_ip);
                    return HTTP_FORBIDDEN;
                }
                uri_addr = uri_addr->next;
            }
            conf_addr = conf_addr->next;
        }
    }
    return OK;
}

/* set up the minimal filter set */
PROXY_DECLARE(int) ap_proxy_pre_http_request(conn_rec *c, request_rec *r)
{
    ap_add_input_filter("HTTP_IN", NULL, r, c);
    return OK;
}

/*
 * converts a series of buckets into a string
 * XXX: BillS says this function performs essentially the same function as
 * ap_rgetline() in protocol.c. Deprecate this function and use ap_rgetline()
 * instead? I think ap_proxy_string_read() will not work properly on non ASCII
 * (EBCDIC) machines either.
 */
PROXY_DECLARE(apr_status_t) ap_proxy_string_read(conn_rec *c, apr_bucket_brigade *bb,
                                                 char *buff, apr_size_t bufflen, int *eos)
{
    apr_bucket *e;
    apr_status_t rv;
    char *pos = buff;
    char *response;
    int found = 0;
    apr_size_t len;

    /* start with an empty string */
    buff[0] = 0;
    *eos = 0;

    /* loop through each brigade */
    while (!found) {
        /* get brigade from network one line at a time */
        if (APR_SUCCESS != (rv = ap_get_brigade(c->input_filters, bb,
                                                AP_MODE_GETLINE,
                                                APR_BLOCK_READ,
                                                0))) {
            return rv;
        }
        /* loop through each bucket */
        while (!found) {
            if (*eos || APR_BRIGADE_EMPTY(bb)) {
                /* The connection aborted or timed out */
                return APR_ECONNABORTED;
            }
            e = APR_BRIGADE_FIRST(bb);
            if (APR_BUCKET_IS_EOS(e)) {
                *eos = 1;
            }
            else {
                if (APR_SUCCESS != apr_bucket_read(e, (const char **)&response, &len, APR_BLOCK_READ)) {
                    return rv;
                }
                /*
                 * is string LF terminated?
                 * XXX: This check can be made more efficient by simply checking
                 * if the last character in the 'response' buffer is an ASCII_LF.
                 * See ap_rgetline() for an example.
                 */
                if (memchr(response, APR_ASCII_LF, len)) {
                    found = 1;
                }
                /* concat strings until buff is full - then throw the data away */
                if (len > ((bufflen-1)-(pos-buff))) {
                    len = (bufflen-1)-(pos-buff);
                }
                if (len > 0) {
                    pos = apr_cpystrn(pos, response, len);
                }
            }
            APR_BUCKET_REMOVE(e);
            apr_bucket_destroy(e);
        }
    }

    return APR_SUCCESS;
}

/* unmerge an element in the table */
PROXY_DECLARE(void) ap_proxy_table_unmerge(apr_pool_t *p, apr_table_t *t, char *key)
{
    apr_off_t offset = 0;
    apr_off_t count = 0;
    char *value = NULL;

    /* get the value to unmerge */
    const char *initial = apr_table_get(t, key);
    if (!initial) {
        return;
    }
    value = apr_pstrdup(p, initial);

    /* remove the value from the headers */
    apr_table_unset(t, key);

    /* find each comma */
    while (value[count]) {
        if (value[count] == ',') {
            value[count] = 0;
            apr_table_add(t, key, value + offset);
            offset = count + 1;
        }
        count++;
    }
    apr_table_add(t, key, value + offset);
}

PROXY_DECLARE(const char *) ap_proxy_location_reverse_map(request_rec *r,
                              proxy_dir_conf *conf, const char *url)
{
    struct proxy_alias *ent;
    int i, l1, l2;
    char *u;

    /*
     * XXX FIXME: Make sure this handled the ambiguous case of the :<PORT>
     * after the hostname
     */

    l1 = strlen(url);
    ent = (struct proxy_alias *)conf->raliases->elts;
    for (i = 0; i < conf->raliases->nelts; i++) {
        l2 = strlen(ent[i].real);
        if (l1 >= l2 && strncasecmp(ent[i].real, url, l2) == 0) {
            u = apr_pstrcat(r->pool, ent[i].fake, &url[l2], NULL);
            return ap_construct_url(r->pool, u, r);
        }
    }

    return url;
}

/*
 * Cookies are a bit trickier to match: we've got two substrings to worry
 * about, and we can't just find them with strstr 'cos of case.  Regexp
 * matching would be an easy fix, but for better consistency with all the
 * other matches we'll refrain and use apr_strmatch to find path=/domain=
 * and stick to plain strings for the config values.
 */
PROXY_DECLARE(const char *) ap_proxy_cookie_reverse_map(request_rec *r,
                              proxy_dir_conf *conf, const char *str)
{
    struct proxy_alias *ent;
    size_t len = strlen(str);
    const char *newpath = NULL;
    const char *newdomain = NULL;
    const char *pathp;
    const char *domainp;
    const char *pathe = NULL;
    const char *domaine = NULL;
    size_t l1, l2, poffs = 0, doffs = 0;
    int i;
    int ddiff = 0;
    int pdiff = 0;
    char *ret;

   /*
    * Find the match and replacement, but save replacing until we've done
    * both path and domain so we know the new strlen
    */
    if ((pathp = apr_strmatch(conf->cookie_path_str, str, len)) != NULL) {
        pathp += 5;
        poffs = pathp - str;
        pathe = ap_strchr_c(pathp, ';');
        l1 = pathe ? (pathe - pathp) : strlen(pathp);
        pathe = pathp + l1 ;
        ent = (struct proxy_alias *)conf->cookie_paths->elts;
        for (i = 0; i < conf->cookie_paths->nelts; i++) {
            l2 = strlen(ent[i].fake);
            if (l1 >= l2 && strncmp(ent[i].fake, pathp, l2) == 0) {
                newpath = ent[i].real;
                pdiff = strlen(newpath) - l1;
                break;
            }
        }
    }

    if ((domainp = apr_strmatch(conf->cookie_domain_str, str, len)) != NULL) {
        domainp += 7;
        doffs = domainp - str;
        domaine = ap_strchr_c(domainp, ';');
        l1 = domaine ? (domaine - domainp) : strlen(domainp);
        domaine = domainp + l1;
        ent = (struct proxy_alias *)conf->cookie_domains->elts;
        for (i = 0; i < conf->cookie_domains->nelts; i++) {
            l2 = strlen(ent[i].fake);
            if (l1 >= l2 && strncasecmp(ent[i].fake, domainp, l2) == 0) {
                newdomain = ent[i].real;
                ddiff = strlen(newdomain) - l1;
                break;
            }
        }
    }

    if (newpath) {
        ret = apr_palloc(r->pool, len + pdiff + ddiff + 1);
        l1 = strlen(newpath);
        if (newdomain) {
            l2 = strlen(newdomain);
            if (doffs > poffs) {
                memcpy(ret, str, poffs);
                memcpy(ret + poffs, newpath, l1);
                memcpy(ret + poffs + l1, pathe, domainp - pathe);
                memcpy(ret + doffs + pdiff, newdomain, l2);
                strcpy(ret + doffs + pdiff + l2, domaine);
            }
            else {
                memcpy(ret, str, doffs) ;
                memcpy(ret + doffs, newdomain, l2);
                memcpy(ret + doffs + l2, domaine, pathp - domaine);
                memcpy(ret + poffs + ddiff, newpath, l1);
                strcpy(ret + poffs + ddiff + l1, pathe);
            }
        }
        else {
            memcpy(ret, str, poffs);
            memcpy(ret + poffs, newpath, l1);
            strcpy(ret + poffs + l1, pathe);
        }
    }
    else {
        if (newdomain) {
            ret = apr_palloc(r->pool, len + pdiff + ddiff + 1);
            l2 = strlen(newdomain);
            memcpy(ret, str, doffs);
            memcpy(ret + doffs, newdomain, l2);
            strcpy(ret + doffs+l2, domaine);
        }
        else {
            ret = (char *)str; /* no change */
        }
    }

    return ret;
}

PROXY_DECLARE(proxy_balancer *) ap_proxy_get_balancer(apr_pool_t *p,
                                                      proxy_server_conf *conf,
                                                      const char *url)
{
    proxy_balancer *balancer;
    char *c, *uri = apr_pstrdup(p, url);
    int i;

    c = strchr(uri, ':');
    if (c == NULL || c[1] != '/' || c[2] != '/' || c[3] == '\0')
       return NULL;
    /* remove path from uri */
    if ((c = strchr(c + 3, '/')))
        *c = '\0';
    balancer = (proxy_balancer *)conf->balancers->elts;
    for (i = 0; i < conf->balancers->nelts; i++) {
        if (strcasecmp(balancer->name, uri) == 0)
            return balancer;
        balancer++;
    }
    return NULL;
}

PROXY_DECLARE(const char *) ap_proxy_add_balancer(proxy_balancer **balancer,
                                                  apr_pool_t *p,
                                                  proxy_server_conf *conf,
                                                  const char *url)
{
    char *c, *q, *uri = apr_pstrdup(p, url);
    proxy_balancer_method *lbmethod;

    c = strchr(uri, ':');
    if (c == NULL || c[1] != '/' || c[2] != '/' || c[3] == '\0')
       return "Bad syntax for a balancer name";
    /* remove path from uri */
    if ((q = strchr(c + 3, '/')))
        *q = '\0';

    ap_str_tolower(uri);
    *balancer = apr_array_push(conf->balancers);
    memset(*balancer, 0, sizeof(proxy_balancer));

    /*
     * NOTE: The default method is byrequests, which we assume
     * exists!
     */
    lbmethod = ap_lookup_provider(PROXY_LBMETHOD, "byrequests", "0");
    if (!lbmethod) {
        return "Can't find 'byrequests' lb method";
    }

    (*balancer)->name = uri;
    (*balancer)->lbmethod = lbmethod;
    (*balancer)->workers = apr_array_make(p, 5, sizeof(proxy_worker));
    /* XXX Is this a right place to create mutex */
#if APR_HAS_THREADS
    if (apr_thread_mutex_create(&((*balancer)->mutex),
                APR_THREAD_MUTEX_DEFAULT, p) != APR_SUCCESS) {
        /* XXX: Do we need to log something here */
        return "can not create thread mutex";
    }
#endif

    return NULL;
}

PROXY_DECLARE(proxy_worker *) ap_proxy_get_worker(apr_pool_t *p,
                                                  proxy_server_conf *conf,
                                                  const char *url)
{
    proxy_worker *worker;
    proxy_worker *max_worker = NULL;
    int max_match = 0;
    int url_length;
    int worker_name_length;
    const char *c;
    char *url_copy;
    int i;

    c = ap_strchr_c(url, ':');
    if (c == NULL || c[1] != '/' || c[2] != '/' || c[3] == '\0')
       return NULL;

    url_copy = apr_pstrdup(p, url);
    url_length = strlen(url);

    /*
     * We need to find the start of the path and
     * therefore we know the length of the scheme://hostname/
     * part to we can force-lowercase everything up to
     * the start of the path.
     */
    c = ap_strchr_c(c+3, '/');