Commit 390c36d0 authored by Colm MacCarthaigh's avatar Colm MacCarthaigh
Browse files 

Fix PR36410; Change how the get_suexec_identity hook is handled by CGID.
Instead of using mod_userdir and mod_suexec specific hacks, we now run the hook
on the httpd side of the handler. 

If this is NULL, we pass on a magic empty_ugid constant, otherwise pass on the
real ugid.

On the cgid side of the equation, we add our own hook, with REALLY_FIRST, and
then order the hooks. This ensures that cgid's doer runs before any other
registered get_suexec_identity doers.

We use cgid's request config to store the ugid. If ugid == empty_ugid, we DON'T
call ap_os_create_privileged_process, because our doer would return the magic
empty_ugid constant. Having the doer return NULL is no good, because then
userdir and mod_suexec's doers would be called. Instead, we call plain old
apr_proc_create(). 



git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@264759 13f79535-47bb-0310-9956-ffa450edef68
parent 4a28da9a

CHANGES

+3 −0
Original line number Diff line number Diff line
@@ -2,6 +2,9 @@ 
Changes with Apache 2.3.0

  [Remove entries to the current 2.0 and 2.2 section below, when backported]













  *) mod_cgid: run the get_suexec_identity hook within the request-handler 













     instead of within cgid. PR36410. [Colm MacCarthaigh]



























  *) Correct mod_cgid's argv[0] so that the full path can be delved by the















     invoked cgi application, to conform to the behavior of mod_cgi.















     [Pradeep Kumar S <pradeep.smani gmail.com>]

































modules/generators/mod_cgid.c



+44
−55






























Original line number
Diff line number
Diff line








@@ -91,10 +91,20 @@ static server_rec *root_server = NULL;













static apr_pool_t *root_pool = NULL;















static const char *sockname;















static pid_t parent_pid;













static ap_unix_identity_t empty_ugid = { -1, -1, -1 };































/* Read and discard the data in the brigade produced by a CGI script */















static void discard_script_output(apr_bucket_brigade *bb);





























/* This doer will only ever be called when we are sure that we have













 * a valid ugid.













 */













static ap_unix_identity_t *cgid_suexec_id_doer(const request_rec *r)













{













    return (ap_unix_identity_t *) 













                        ap_get_module_config(r->request_config, &cgid_module);













}





























/* KLUDGE --- for back-combatibility, we don't have to check ExecCGI















 * in ScriptAliased directories, which means we need to know if this 















 * request came through ScriptAlias or not... so the Alias module 










@@ -159,15 +169,12 @@ typedef struct {













                            * wrong cgid socket use















                            */















    int core_module_index;













    int have_suexec;













    int suexec_module_index;













    suexec_config_t suexec_cfg;















    int env_count;













    ap_unix_identity_t ugid;















    apr_size_t filename_len;















    apr_size_t argv0_len;















    apr_size_t uri_len;















    apr_size_t args_len;













    apr_size_t mod_userdir_user_len;















    int loglevel; /* to stuff in server_rec */















} cgid_req_t;


























@@ -328,10 +335,9 @@ static apr_status_t get_req(int fd, request_rec *r, char **argv0, char ***env,













                            cgid_req_t *req)















{ 















    int i; 













    char *user;















    char **environ; 













    core_dir_config *temp_core; 













    void **dconf;













    core_request_config *temp_core; 













    void **rconf;















    apr_status_t stat;































    r->server = apr_pcalloc(r->pool, sizeof(server_rec)); 









@@ -348,16 +354,12 @@ static apr_status_t get_req(int fd, request_rec *r, char **argv0, char ***env,













    }































    /* handle module indexes and such */













    dconf = (void **) apr_pcalloc(r->pool, sizeof(void *) * (total_modules + DYNAMIC_MODULE_LIMIT));



























    temp_core = (core_dir_config *)apr_palloc(r->pool, sizeof(core_module)); 













    dconf[req->core_module_index] = (void *)temp_core;



























    if (req->have_suexec) {













        dconf[req->suexec_module_index] = &req->suexec_cfg;













    }













    rconf = (void **) apr_pcalloc(r->pool, sizeof(void *) * (total_modules + DYNAMIC_MODULE_LIMIT));





























    r->per_dir_config = (ap_conf_vector_t *)dconf; 













    temp_core = (core_request_config *)apr_palloc(r->pool, sizeof(core_module)); 













    rconf[req->core_module_index] = (void *)temp_core;













    r->request_config = (ap_conf_vector_t *)rconf; 













    ap_set_module_config(r->request_config, &cgid_module, (void *)&req->ugid);















    















    /* Read the filename, argv0, uri, and args */















    r->filename = apr_pcalloc(r->pool, req->filename_len + 1);










@@ -391,19 +393,6 @@ static apr_status_t get_req(int fd, request_rec *r, char **argv0, char ***env,













    }















    *env = environ;





























    /* basic notes table to avoid segfaults */













    r->notes = apr_table_make(r->pool, 1);



























    /* mod_userdir requires the mod_userdir_user note */













    if (req->mod_userdir_user_len) {













        user = apr_pcalloc(r->pool, req->mod_userdir_user_len + 1); /* last byte is '\0' */













        stat = sock_read(fd, user, req->mod_userdir_user_len);













        if (stat != APR_SUCCESS) {













            return stat;













        }













        apr_table_set(r->notes, "mod_userdir_user", (const char *)user);













    }





























#if 0















#ifdef RLIMIT_CPU 















    sock_read(fd, &j, sizeof(int)); 










@@ -446,23 +435,20 @@ static apr_status_t send_req(int fd, request_rec *r, char *argv0, char **env,













                             int req_type) 















{ 















    int i;













    const char *user;













    module *suexec_mod = ap_find_linked_module("mod_suexec.c");















    cgid_req_t req = {0};













    suexec_config_t *suexec_cfg;















    apr_status_t stat;













    ap_unix_identity_t * ugid = ap_run_get_suexec_identity(r);



























    if (ugid == NULL) {













        req.ugid = empty_ugid;













    } else {













        memcpy(&req.ugid, ugid, sizeof(ap_unix_identity_t));













    }















    















    req.req_type = req_type;















    req.ppid = parent_pid;















    req.conn_id = r->connection->id;















    req.core_module_index = core_module.module_index;













    if (suexec_mod) {













        req.have_suexec = 1;













        req.suexec_module_index = suexec_mod->module_index;













        suexec_cfg = ap_get_module_config(r->per_dir_config,













                                          suexec_mod);













        req.suexec_cfg = *suexec_cfg;













    }















    for (req.env_count = 0; env[req.env_count]; req.env_count++) {















        continue; 















    }









@@ -470,10 +456,6 @@ static apr_status_t send_req(int fd, request_rec *r, char *argv0, char **env,













    req.argv0_len = strlen(argv0);















    req.uri_len = strlen(r->uri);















    req.args_len = r->args ? strlen(r->args) : 0;













    user = (const char *)apr_table_get(r->notes, "mod_userdir_user");













    if (user != NULL) {













        req.mod_userdir_user_len = strlen(user);













    }















    req.loglevel = r->server->loglevel;































    /* Write the request header */










@@ -506,13 +488,6 @@ static apr_status_t send_req(int fd, request_rec *r, char *argv0, char **env,













        }















    }





























    /* send a minimal notes table */













    if (user) {













        if ((stat = sock_write(fd, user, req.mod_userdir_user_len)) != APR_SUCCESS) {













            return stat;













        }













    }





























#if 0















#ifdef RLIMIT_CPU 















    if (conf->limit_cpu) { 










@@ -594,6 +569,11 @@ static int cgid_server(void *data)













    /* Close our copy of the listening sockets */















    ap_close_listeners();





























    /* cgid should use its own suexec doer */













    ap_hook_get_suexec_identity(cgid_suexec_id_doer, NULL, NULL,













                                APR_HOOK_REALLY_FIRST);













    apr_hook_sort_all();













    















    if ((sd = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) {















        ap_log_error(APLOG_MARK, APLOG_ERR, errno, main_server, 















                     "Couldn't create unix domain socket");










@@ -753,9 +733,18 @@ static int cgid_server(void *data)













            */















            close(sd2);





























            if (memcmp(&empty_ugid, &cgid_req.ugid, sizeof(empty_ugid))) {













                /* We have a valid identity, and can be sure that 













                 * cgid_suexec_id_doer will return a valid ugid 













                 */















                rc = ap_os_create_privileged_process(r, procnew, argv0, argv,















                                                     (const char * const *)env,















                                                     procattr, ptrans);













            } else {













                rc = apr_proc_create(procnew, argv0, argv, 













                                     (const char * const *)env, 













                                     procattr, ptrans);













            }















                















            if (rc != APR_SUCCESS) {















                /* Bad things happened. Everyone should have cleaned up.