diff options
Diffstat (limited to 'trace.c')
| -rw-r--r-- | trace.c | 373 |
1 files changed, 189 insertions, 184 deletions
@@ -1,8 +1,8 @@ -/*----------------------------------------------------------------------------*/ +/*---------------------------------------------------------------------------*/ /*trace.h*/ -/*----------------------------------------------------------------------------*/ +/*---------------------------------------------------------------------------*/ /*The definitions for tracing the translator stack under ourselves.*/ -/*----------------------------------------------------------------------------*/ +/*---------------------------------------------------------------------------*/ /*Copyright (C) 2001, 2002, 2005, 2008 Free Software Foundation, Inc. Written by Sergiu Ivanov <unlimitedscolobb@gmail.com>. @@ -20,195 +20,200 @@ along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.*/ -/*----------------------------------------------------------------------------*/ +/*---------------------------------------------------------------------------*/ -/*----------------------------------------------------------------------------*/ +/*---------------------------------------------------------------------------*/ #define _GNU_SOURCE 1 -/*----------------------------------------------------------------------------*/ +/*---------------------------------------------------------------------------*/ #include <unistd.h> #include <fcntl.h> #include <hurd/fsys.h> -/*----------------------------------------------------------------------------*/ +/*---------------------------------------------------------------------------*/ #include "debug.h" #include "trace.h" #include "node.h" -/*----------------------------------------------------------------------------*/ +/*---------------------------------------------------------------------------*/ -/*----------------------------------------------------------------------------*/ -/*--------Functions-----------------------------------------------------------*/ -/*Traces the translator stack on the given underlying node until it finds the - first translator called `name` and returns the port pointing to the - translator sitting under this one.*/ +/*---------------------------------------------------------------------------*/ +/*--------Functions----------------------------------------------------------*/ +/*Traces the translator stack on the given underlying node until it + finds the first translator called `name` and returns the port + pointing to the translator sitting under this one.*/ error_t -trace_find - ( - mach_port_t underlying, - const char * name, - int flags, - mach_port_t * port - ) + trace_find + (mach_port_t underlying, const char *name, int flags, mach_port_t * port) +{ + error_t err = 0; + + /*Identity information about the current process */ + uid_t *uids; + size_t nuids; + + gid_t *gids; + size_t ngids; + + /*The name and arguments of the translator being passed now */ + char *argz = NULL; + size_t argz_len = 0; + + /*The current working directory */ + char *cwd = NULL; + + /*The port to the directory containing the file pointed to by `underlying` */ + file_t dir; + + /*The unauthenticated version of `dir` */ + file_t unauth_dir; + + /*The control port of the current translator */ + fsys_t fsys; + + /*The port to the translator we are currently looking at */ + mach_port_t node = underlying; + + /*The port to the previous translator */ + mach_port_t prev_node = MACH_PORT_NULL; + + /*The retry name and retry type returned by fsys_getroot */ + string_t retry_name; + retry_type retry; + + /*Finalizes the execution of this function */ + void finalize (void) + { + /*If there is a working directory, free it */ + if (cwd) + free (cwd); + + /*If the ports to the directory exist */ + if (dir) + PORT_DEALLOC (dir); + } /*finalize */ + + /*Obtain the current working directory */ + cwd = getcwd (NULL, 0); + if (!cwd) + { + LOG_MSG ("trace_find: Could not obtain cwd."); + return EINVAL; + } + LOG_MSG ("trace_find: cwd: '%s'", cwd); + + /*Open a port to this directory */ + dir = file_name_lookup (cwd, 0, 0); + if (!dir) + { + finalize (); + return ENOENT; + } + + /*Try to get the number of effective UIDs */ + nuids = geteuids (0, 0); + if (nuids < 0) + { + finalize (); + return EINVAL; + } + + /*Allocate some memory for the UIDs on the stack */ + uids = alloca (nuids * sizeof (uid_t)); + + /*Fetch the UIDs themselves */ + nuids = geteuids (nuids, uids); + if (nuids < 0) + { + finalize (); + return EINVAL; + } + + /*Try to get the number of effective GIDs */ + ngids = getgroups (0, 0); + if (ngids < 0) + { + finalize (); + return EINVAL; + } + + /*Allocate some memory for the GIDs on the stack */ + gids = alloca (ngids * sizeof (gid_t)); + + /*Fetch the GIDs themselves */ + ngids = getgroups (ngids, gids); + if (ngids < 0) + { + finalize (); + return EINVAL; + } + + /*Obtain the unauthenticated version of `dir` */ + err = io_restrict_auth (dir, &unauth_dir, 0, 0, 0, 0); + if (err) + { + finalize (); + return err; + } + + char buf[256]; + char *_buf = buf; + size_t len = 256; + io_read (node, &_buf, &len, 0, len); + LOG_MSG ("trace_find: Read from underlying: '%s'", buf); + + /*Go up the translator stack */ + for (; !err;) + { + /*retreive the name and options of the current translator */ + err = file_get_fs_options (node, &argz, &argz_len); + if (err) + break; + + LOG_MSG ("trace_find: Obtained translator '%s'", argz); + if (strcmp (argz, name) == 0) { - error_t err = 0; - - /*Identity information about the current process*/ - uid_t * uids; - size_t nuids; - - gid_t * gids; - size_t ngids; - - /*The name and arguments of the translator being passed now*/ - char * argz = NULL; - size_t argz_len = 0; - - /*The current working directory*/ - char * cwd = NULL; - - /*The port to the directory containing the file pointed to by `underlying`*/ - file_t dir; - - /*The unauthenticated version of `dir`*/ - file_t unauth_dir; - - /*The control port of the current translator*/ - fsys_t fsys; - - /*The port to the translator we are currently looking at*/ - mach_port_t node = underlying; - - /*The retry name and retry type returned by fsys_getroot*/ - string_t retry_name; - retry_type retry; - - /*Finalizes the execution of this function*/ - void - finalize(void) - { - /*If there is a working directory, free it*/ - if(cwd) - free(cwd); - - /*If the ports to the directory exist*/ - if(dir) - PORT_DEALLOC(dir); - }/*finalize*/ - - /*Obtain the current working directory*/ - cwd = getcwd(NULL, 0); - if(!cwd) - { - LOG_MSG("trace_find: Could not obtain cwd."); - return EINVAL; - } - LOG_MSG("trace_find: cwd: '%s'", cwd); - - /*Open a port to this directory*/ - dir = file_name_lookup(cwd, 0, 0); - if(!dir) - { - finalize(); - return ENOENT; - } - - /*Try to get the number of effective UIDs*/ - nuids = geteuids(0, 0); - if(nuids < 0) - { - finalize(); - return EINVAL; - } - - /*Allocate some memory for the UIDs on the stack*/ - uids = alloca(nuids * sizeof(uid_t)); - - /*Fetch the UIDs themselves*/ - nuids = geteuids(nuids, uids); - if(nuids < 0) - { - finalize(); - return EINVAL; - } - - /*Try to get the number of effective GIDs*/ - ngids = getgroups(0, 0); - if(ngids < 0) - { - finalize(); - return EINVAL; - } - - /*Allocate some memory for the GIDs on the stack*/ - gids = alloca(ngids * sizeof(gid_t)); - - /*Fetch the GIDs themselves*/ - ngids = getgroups(ngids, gids); - if(ngids < 0) - { - finalize(); - return EINVAL; - } - - /*Obtain the unauthenticated version of `dir`*/ - err = io_restrict_auth(dir, &unauth_dir, 0, 0, 0, 0); - if(err) - { - finalize(); - return err; - } - - /*Go up the translator stack*/ - for(; !err;) - { - /*retreive the name and options of the current translator*/ - err = file_get_fs_options(node, &argz, &argz_len); - if(err) - break; - - LOG_MSG("trace_find: Obtained translator '%s'", argz); - if(strcmp(argz, name) == 0) - { - LOG_MSG("trace_find: Match. Stopping here."); - break; - } - - /*try to fetch the control port for this translator*/ - err = file_get_translator_cntl(node, &fsys); - LOG_MSG("trace_find: err = %d", (int)err); - if(err) - break; - - LOG_MSG("trace_find: Translator control port: %lu", (unsigned long)fsys); - - /*fetch the root of the translator*/ - err = fsys_getroot - ( - fsys, unauth_dir, MACH_MSG_TYPE_COPY_SEND, - uids, nuids, gids, ngids, - flags | O_NOTRANS, &retry, retry_name, &node - ); - - LOG_MSG("trace_find: fsys_getroot returned %d", (int)err); - LOG_MSG("trace_find: Translator root: %lu", (unsigned long)node); - - /*TODO: Remove this debug output.*/ - char buf[256]; - char * _buf = buf; - size_t len = 256; - io_read(node, &_buf, &len, 0, len); - LOG_MSG("trace_find: Read: '%s'", buf); - } - - /*If the error occurred (most probably) because of the fact that we - have reached the top of the translator stack*/ - if((err == EMACH_SEND_INVALID_DEST) || (err == ENXIO)) - /*this is OK*/ - err = 0; - - /*Return the port to read from*/ - *port = node; - - /*Return the result of operations*/ - finalize(); - return err; - }/*trace_find*/ -/*----------------------------------------------------------------------------*/ + LOG_MSG ("trace_find: Match. Stopping here."); + break; + } + + /*try to fetch the control port for this translator */ + err = file_get_translator_cntl (node, &fsys); + LOG_MSG ("trace_find: err = %d", (int) err); + if (err) + break; + + LOG_MSG ("trace_find: Translator control port: %lu", + (unsigned long) fsys); + + prev_node = node; + + /*fetch the root of the translator */ + err = fsys_getroot + (fsys, unauth_dir, MACH_MSG_TYPE_COPY_SEND, + uids, nuids, gids, ngids, + flags | O_NOTRANS, &retry, retry_name, &node); + + LOG_MSG ("trace_find: fsys_getroot returned %d", (int) err); + LOG_MSG ("trace_find: Translator root: %lu", (unsigned long) node); + + /*TODO: Remove this debug output. */ + /*char buf[256]; + char * _buf = buf; + size_t len = 256; + io_read(node, &_buf, &len, 0, len); + LOG_MSG("trace_find: Read: '%s'", buf); */ + } + + /*If the error occurred (most probably) because of the fact that we + have reached the top of the translator stack */ + if ((err == EMACH_SEND_INVALID_DEST) || (err == ENXIO)) + /*this is OK */ + err = 0; + + /*Return the port to read from */ + *port = prev_node; + + /*Return the result of operations */ + finalize (); + return err; +} /*trace_find */ + +/*---------------------------------------------------------------------------*/ |