mod_proxy.c

来自「apache服务器源代码（版本号：2.2.2）」· C语言 代码 · 共 1,862 行 · 第 1/5 页

            }
        }

        /* otherwise, try it direct */
        /* N.B. what if we're behind a firewall, where we must use a proxy or
        * give up??
        */

        /* handle the scheme */
        ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
                     "Running scheme %s handler (attempt %d)",
                     scheme, attempts);
        access_status = proxy_run_scheme_handler(r, worker, conf,
                                                 url, NULL, 0);
        if (access_status == OK)
            break;
        else if (access_status == HTTP_INTERNAL_SERVER_ERROR) {
            /* Unrecoverable server error.
             * We can not failover to another worker.
             * Mark the worker as unusable if member of load balancer
             */
            if (balancer)
                worker->s->status |= PROXY_WORKER_IN_ERROR;
            break;
        }
        else if (access_status == HTTP_SERVICE_UNAVAILABLE) {
            /* Recoverable server error.
             * We can failover to another worker
             * Mark the worker as unusable if member of load balancer
             */
            if (balancer) {
                worker->s->status |= PROXY_WORKER_IN_ERROR;
            }
        }
        else {
            /* Unrecoverable error.
             * Return the origin status code to the client.
             */
            break;
        }
        /* Try again if the worker is unusable and the service is
         * unavailable.
         */
    } while (!PROXY_WORKER_IS_USABLE(worker) &&
             max_attempts > attempts++);

    if (DECLINED == access_status) {
        ap_log_error(APLOG_MARK, APLOG_WARNING, 0, r->server,
                    "proxy: No protocol handler was valid for the URL %s. "
                    "If you are using a DSO version of mod_proxy, make sure "
                    "the proxy submodules are included in the configuration "
                    "using LoadModule.", r->uri);
        access_status = HTTP_FORBIDDEN;
        goto cleanup;
    }
cleanup:
    if (balancer) {
        int post_status = proxy_run_post_request(worker, balancer, r, conf);
        if (post_status == DECLINED) {
            post_status = OK; /* no post_request handler available */
            /* TODO: recycle direct worker */
        }
    }

    proxy_run_request_status(&access_status, r);

    return access_status;
}

/* -------------------------------------------------------------- */
/* Setup configurable data */

static void * create_proxy_config(apr_pool_t *p, server_rec *s)
{
    proxy_server_conf *ps = apr_pcalloc(p, sizeof(proxy_server_conf));

    ps->sec_proxy = apr_array_make(p, 10, sizeof(ap_conf_vector_t *));
    ps->proxies = apr_array_make(p, 10, sizeof(struct proxy_remote));
    ps->aliases = apr_array_make(p, 10, sizeof(struct proxy_alias));
    ps->noproxies = apr_array_make(p, 10, sizeof(struct noproxy_entry));
    ps->dirconn = apr_array_make(p, 10, sizeof(struct dirconn_entry));
    ps->allowed_connect_ports = apr_array_make(p, 10, sizeof(int));
    ps->workers = apr_array_make(p, 10, sizeof(proxy_worker));
    ps->balancers = apr_array_make(p, 10, sizeof(proxy_balancer));
    ps->forward = NULL;
    ps->reverse = NULL;
    ps->domain = NULL;
    ps->viaopt = via_off; /* initially backward compatible with 1.3.1 */
    ps->viaopt_set = 0; /* 0 means default */
    ps->req = 0;
    ps->req_set = 0;
    ps->recv_buffer_size = 0; /* this default was left unset for some reason */
    ps->recv_buffer_size_set = 0;
    ps->io_buffer_size = AP_IOBUFSIZE;
    ps->io_buffer_size_set = 0;
    ps->maxfwd = DEFAULT_MAX_FORWARDS;
    ps->maxfwd_set = 0;
    ps->error_override = 0;
    ps->error_override_set = 0;
    ps->preserve_host_set = 0;
    ps->preserve_host = 0;
    ps->timeout = 0;
    ps->timeout_set = 0;
    ps->badopt = bad_error;
    ps->badopt_set = 0;
    ps->pool = p;

    return ps;
}

static void * merge_proxy_config(apr_pool_t *p, void *basev, void *overridesv)
{
    proxy_server_conf *ps = apr_pcalloc(p, sizeof(proxy_server_conf));
    proxy_server_conf *base = (proxy_server_conf *) basev;
    proxy_server_conf *overrides = (proxy_server_conf *) overridesv;

    ps->proxies = apr_array_append(p, base->proxies, overrides->proxies);
    ps->sec_proxy = apr_array_append(p, base->sec_proxy, overrides->sec_proxy);
    ps->aliases = apr_array_append(p, base->aliases, overrides->aliases);
    ps->noproxies = apr_array_append(p, base->noproxies, overrides->noproxies);
    ps->dirconn = apr_array_append(p, base->dirconn, overrides->dirconn);
    ps->allowed_connect_ports = apr_array_append(p, base->allowed_connect_ports, overrides->allowed_connect_ports);
    ps->workers = apr_array_append(p, base->workers, overrides->workers);
    ps->balancers = apr_array_append(p, base->balancers, overrides->balancers);
    ps->forward = overrides->forward ? overrides->forward : base->forward;
    ps->reverse = overrides->reverse ? overrides->reverse : base->reverse;

    ps->domain = (overrides->domain == NULL) ? base->domain : overrides->domain;
    ps->viaopt = (overrides->viaopt_set == 0) ? base->viaopt : overrides->viaopt;
    ps->req = (overrides->req_set == 0) ? base->req : overrides->req;
    ps->recv_buffer_size = (overrides->recv_buffer_size_set == 0) ? base->recv_buffer_size : overrides->recv_buffer_size;
    ps->io_buffer_size = (overrides->io_buffer_size_set == 0) ? base->io_buffer_size : overrides->io_buffer_size;
    ps->maxfwd = (overrides->maxfwd_set == 0) ? base->maxfwd : overrides->maxfwd;
    ps->error_override = (overrides->error_override_set == 0) ? base->error_override : overrides->error_override;
    ps->preserve_host = (overrides->preserve_host_set == 0) ? base->preserve_host : overrides->preserve_host;
    ps->timeout= (overrides->timeout_set == 0) ? base->timeout : overrides->timeout;
    ps->badopt = (overrides->badopt_set == 0) ? base->badopt : overrides->badopt;
    ps->proxy_status = (overrides->proxy_status_set == 0) ? base->proxy_status : overrides->proxy_status;
    ps->pool = p;
    return ps;
}

static void *create_proxy_dir_config(apr_pool_t *p, char *dummy)
{
    proxy_dir_conf *new =
        (proxy_dir_conf *) apr_pcalloc(p, sizeof(proxy_dir_conf));

    /* Filled in by proxysection, when applicable */

    /* Put these in the dir config so they work inside <Location> */
    new->raliases = apr_array_make(p, 10, sizeof(struct proxy_alias));
    new->cookie_paths = apr_array_make(p, 10, sizeof(struct proxy_alias));
    new->cookie_domains = apr_array_make(p, 10, sizeof(struct proxy_alias));
    new->cookie_path_str = apr_strmatch_precompile(p, "path=", 0);
    new->cookie_domain_str = apr_strmatch_precompile(p, "domain=", 0);

    return (void *) new;
}

static void *merge_proxy_dir_config(apr_pool_t *p, void *basev, void *addv)
{
    proxy_dir_conf *new = (proxy_dir_conf *) apr_pcalloc(p, sizeof(proxy_dir_conf));
    proxy_dir_conf *add = (proxy_dir_conf *) addv;
    proxy_dir_conf *base = (proxy_dir_conf *) basev;

    new->p = add->p;
    new->p_is_fnmatch = add->p_is_fnmatch;
    new->r = add->r;

    /* Put these in the dir config so they work inside <Location> */
    new->raliases = apr_array_append(p, base->raliases, add->raliases);
    new->cookie_paths
        = apr_array_append(p, base->cookie_paths, add->cookie_paths);
    new->cookie_domains
        = apr_array_append(p, base->cookie_domains, add->cookie_domains);
    new->cookie_path_str = base->cookie_path_str;
    new->cookie_domain_str = base->cookie_domain_str;
    return new;
}


static const char *
    add_proxy(cmd_parms *cmd, void *dummy, const char *f1, const char *r1, int regex)
{
    server_rec *s = cmd->server;
    proxy_server_conf *conf =
    (proxy_server_conf *) ap_get_module_config(s->module_config, &proxy_module);
    struct proxy_remote *new;
    char *p, *q;
    char *r, *f, *scheme;
    ap_regex_t *reg = NULL;
    int port;

    r = apr_pstrdup(cmd->pool, r1);
    scheme = apr_pstrdup(cmd->pool, r1);
    f = apr_pstrdup(cmd->pool, f1);
    p = strchr(r, ':');
    if (p == NULL || p[1] != '/' || p[2] != '/' || p[3] == '\0') {
        if (regex)
            return "ProxyRemoteMatch: Bad syntax for a remote proxy server";
        else
            return "ProxyRemote: Bad syntax for a remote proxy server";
    }
    else {
        scheme[p-r] = 0;
    }
    q = strchr(p + 3, ':');
    if (q != NULL) {
        if (sscanf(q + 1, "%u", &port) != 1 || port > 65535) {
            if (regex)
                return "ProxyRemoteMatch: Bad syntax for a remote proxy server (bad port number)";
            else
                return "ProxyRemote: Bad syntax for a remote proxy server (bad port number)";
        }
        *q = '\0';
    }
    else
        port = -1;
    *p = '\0';
    if (regex) {
        reg = ap_pregcomp(cmd->pool, f, AP_REG_EXTENDED);
        if (!reg)
            return "Regular expression for ProxyRemoteMatch could not be compiled.";
    }
    else
        if (strchr(f, ':') == NULL)
            ap_str_tolower(f);      /* lowercase scheme */
    ap_str_tolower(p + 3);      /* lowercase hostname */

    if (port == -1) {
        port = apr_uri_port_of_scheme(scheme);
    }

    new = apr_array_push(conf->proxies);
    new->scheme = f;
    new->protocol = r;
    new->hostname = p + 3;
    new->port = port;
    new->regexp = reg;
    new->use_regex = regex;
    return NULL;
}

static const char *
    add_proxy_noregex(cmd_parms *cmd, void *dummy, const char *f1, const char *r1)
{
    return add_proxy(cmd, dummy, f1, r1, 0);
}

static const char *
    add_proxy_regex(cmd_parms *cmd, void *dummy, const char *f1, const char *r1)
{
    return add_proxy(cmd, dummy, f1, r1, 1);
}

static const char *
    add_pass(cmd_parms *cmd, void *dummy, const char *arg)
{
    server_rec *s = cmd->server;
    proxy_server_conf *conf =
    (proxy_server_conf *) ap_get_module_config(s->module_config, &proxy_module);
    struct proxy_alias *new;
    char *f = cmd->path;
    char *r = NULL;
    char *word;
    apr_table_t *params = apr_table_make(cmd->pool, 5);
    const apr_array_header_t *arr;
    const apr_table_entry_t *elts;
    int i;

    while (*arg) {
        word = ap_getword_conf(cmd->pool, &arg);
        if (!f)
            f = word;
        else if (!r)
            r = word;
        else {
            char *val = strchr(word, '=');
            if (!val) {
                if (cmd->path)
                    return "Invalid ProxyPass parameter.  Parameter must be "
                           "in the form 'key=value'";
                else
                    return "ProxyPass can not have a path when defined in a location";
            }
            else
                *val++ = '\0';
            apr_table_setn(params, word, val);
        }
    };

    if (r == NULL)
        return "ProxyPass needs a path when not defined in a location";

    new = apr_array_push(conf->aliases);
    new->fake = apr_pstrdup(cmd->pool, f);
    new->real = apr_pstrdup(cmd->pool, r);
    if (r[0] == '!' && r[1] == '\0')
        return NULL;

    arr = apr_table_elts(params);
    elts = (const apr_table_entry_t *)arr->elts;
    /* Distinguish the balancer from woker */
    if (strncasecmp(r, "balancer:", 9) == 0) {
        proxy_balancer *balancer = ap_proxy_get_balancer(cmd->pool, conf, r);
        if (!balancer) {
            const char *err = ap_proxy_add_balancer(&balancer,
                                                    cmd->pool,
                                                    conf, r);
            if (err)
                return apr_pstrcat(cmd->temp_pool, "ProxyPass ", err, NULL);
        }
        for (i = 0; i < arr->nelts; i++) {
            const char *err = set_balancer_param(conf, cmd->pool, balancer, elts[i].key,
                                                 elts[i].val);
            if (err)
                return apr_pstrcat(cmd->temp_pool, "ProxyPass ", err, NULL);
        }
    }
    else {
        proxy_worker *worker = ap_proxy_get_worker(cmd->temp_pool, conf, r);
        if (!worker) {
            const char *err = ap_proxy_add_worker(&worker, cmd->pool, conf, r);
            if (err)
                return apr_pstrcat(cmd->temp_pool, "ProxyPass ", err, NULL);
        }
        PROXY_COPY_CONF_PARAMS(worker, conf);

        for (i = 0; i < arr->nelts; i++) {
            const char *err = set_worker_param(cmd->pool, worker, elts[i].key,
                                               elts[i].val);
            if (err)
                return apr_pstrcat(cmd->temp_pool, "ProxyPass ", err, NULL);
        }
    }
    return NULL;
}

static const char *
    add_pass_reverse(cmd_parms *cmd, void *dconf, const char *f, const char *r)
{
    proxy_dir_conf *conf = dconf;
    struct proxy_alias *new;

    if (r!=NULL && cmd->path == NULL ) {
        new = apr_array_push(conf->raliases);
        new->fake = f;
        new->real = r;
    } else if (r==NULL && cmd->path != NULL) {
        new = apr_array_push(conf->raliases);
        new->fake = cmd->path;
        new->real = f;
    } else {
        if ( r == NULL)
            return "ProxyPassReverse needs a path when not defined in a location";
        else
            return "ProxyPassReverse can not have a path when defined in a location";
    }

    return NULL;
}
static const char*
    cookie_path(cmd_parms *cmd, void *dconf, const char *f, const char *r)
{
    proxy_dir_conf *conf = dconf;
    struct proxy_alias *new;

    new = apr_array_push(conf->cookie_paths);
    new->fake = f;
    new->real = r;

    return NULL;
}