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/****************************************************************
* *
* Copyright 2009, 2013 Fidelity Information Services, Inc *
* *
* This source code contains the intellectual property *
* of its copyright holder(s), and is made available *
* under a license. If you do not know the terms of *
* the license, please stop and do not read further. *
* *
****************************************************************/
#include "mdef.h"
#include "eintr_wrappers.h"
#include "gtm_string.h"
#include "gtm_stdio.h"
#include "gtm_stdlib.h"
#include "gtm_limits.h"
#include "gtm_unistd.h"
#include "gtm_fcntl.h"
#include "gtm_stat.h"
#include "gtm_pwd.h"
#include <grp.h>
#include "gtm_permissions.h"
#include "send_msg.h"
#if defined(__hpux) && defined(__hppa)
# define LIBGTMSHR "%s/libgtmshr.sl"
#elif defined(__MVS__)
# define LIBGTMSHR "%s/libgtmshr.dll"
#else
# define LIBGTMSHR "%s/libgtmshr.so"
#endif
/* Return the group id of the distribution based on libgtmshr.xx[x]. If there is some
problem accessing that file then return -1 which signals no change to group. Otherwise,
the pointer to the stat buffer will contain the result of the call to STAT_FILE */
int gtm_get_group_id(struct stat *stat_buff)
{
char *env_var;
int ret_stat;
char temp[PATH_MAX + SIZEOF("libgtmshr.dll")];
env_var = GETENV("gtm_dist");
if (NULL != env_var)
{
/* build a path to libgtmshr.so or .sl on hpux or .dll on zos */
SNPRINTF(temp, SIZEOF(temp), LIBGTMSHR, env_var);
STAT_FILE(temp, stat_buff, ret_stat);
if (0 == ret_stat)
return(stat_buff->st_gid);
}
/* return a -1 if $gtm_dist found or if STAT_FILE returned a -1 */
return(-1);
}
/* Return TRUE is the "uid" parameter is a member of the "gid" group parameter.
Return FALSE if it is not. */
int gtm_member_group_id(int uid, int gid)
{
struct group *grp;
struct passwd *pwd, *pwd2;
/* check effective group if current effective uid */
if ((GETEUID() == uid) && (GETEGID() == gid))
return(TRUE);
/* get group id for database */
grp = getgrgid(gid);
if (NULL == grp)
return(FALSE); /* if group id not found then assume uid not a member */
pwd = getpwuid(uid);
if (NULL == pwd)
return(FALSE); /* if user id not found then assume uid not a member */
/* if the gid of the file is the same as the gid for the process uid we are done */
if (gid == pwd->pw_gid)
return(TRUE);
else
{
/*
* Otherwise we have to compare the name stored in pwd struct
* with the names of the group members in the group struct.
*/
while (NULL != *(grp->gr_mem))
{
if (!strcmp(pwd->pw_name, *(grp->gr_mem++)))
return(TRUE);
}
return(FALSE);
}
}
/* Based on security rules in this routine, set *group_id of the group to be used
* for shared resources, journals, and temp files. If a no change then it will be set to -1.
* Also, set *perm to the permissions to be used. The precalculated world_write_perm (need to
* change name to masked_permissions) is to be used in the one case indicated below.
* If the user is root, the *user_id may be set to a target uid if needed; otherwise, it will
* be set to -1.
*
* Populates pdd struct and returns negative value for error, returns non-negative for success.
*/
int gtm_permissions(struct stat *stat_buff, int *user_id, int *group_id, int *perm, enum perm_target_types target_type,
struct perm_diag_data *pdd)
{
int lib_gid = -1;
int use_world_writeable;
uid_t process_uid;
gid_t process_gid;
uid_t db_uid;
struct stat dist_stat_buff;
int opener_is_file_owner;
int opener_is_root;
int opener_in_file_group;
int owner_in_file_group;
int gtm_group_restricted;
/* get process_uid/gid */
process_uid = GETEUID();
process_gid = GETEGID();
/* get database uid */
db_uid = stat_buff->st_uid;
/* set variables for permission logic */
opener_is_file_owner = (process_uid == db_uid);
opener_is_root = (process_uid == 0);
opener_in_file_group = gtm_member_group_id(process_uid, stat_buff->st_gid);
owner_in_file_group = gtm_member_group_id(db_uid, stat_buff->st_gid);
/* find restricted group, if any */
lib_gid = gtm_get_group_id(&dist_stat_buff);
gtm_group_restricted = (lib_gid != -1) && !(dist_stat_buff.st_mode & 01); /* not world executable */
/* set default gid */
#ifdef __osf__
*user_id = process_uid;
*group_id = process_gid;
#else
*user_id = -1;
*group_id = -1;
#endif
/* set no permissions as a default in case none of our conditions match */
*perm = 0;
assertpro((PERM_FILE == target_type) || (PERM_IPC == target_type));
if (0006 & stat_buff->st_mode)
{
/* file is accessible to other */
if (opener_is_root) /* otherwise, use default uid */
*user_id = stat_buff->st_uid;
if (opener_in_file_group || opener_is_root) /* otherwise, use default gid */
*group_id = stat_buff->st_gid;
if (PERM_FILE == target_type)
*perm = (!opener_in_file_group && !opener_is_root && (0020 & stat_buff->st_mode))
? 0666 : (stat_buff->st_mode & 0666);
else if (PERM_IPC == target_type)
*perm = 0666;
} else if (0600 & stat_buff->st_mode && !(0066 & stat_buff->st_mode))
{
/* file is only user accessible */
/* use default group */
assert(opener_is_file_owner || opener_is_root);
if (opener_is_root) /* otherwise, use default uid/gid */
{
*user_id = stat_buff->st_uid;
*group_id = stat_buff->st_gid;
}
if (PERM_FILE == target_type)
*perm = 0600; /* read write for user */
else if (PERM_IPC == target_type)
*perm = 0600; /* read write for user */
} else if (0060 & stat_buff->st_mode && !(0606 & stat_buff->st_mode))
{
/* file is only group accessible */
if (opener_is_root) /* otherwise, use default uid */
*user_id = stat_buff->st_uid;
*group_id = stat_buff->st_gid; /* use file group */
assert(opener_in_file_group || opener_is_root);
if (PERM_FILE == target_type)
*perm = stat_buff->st_mode & 0060; /* use file permissions, masked for group read/write */
if (PERM_IPC == target_type)
*perm = 0660; /* read/write for group - all readers need write for ipc */
} else
{
/* file is accessible to user and group */
if (opener_is_file_owner && opener_in_file_group || opener_is_root)
{
if (opener_is_root) /* otherwise, use default uid */
*user_id = stat_buff->st_uid;
*group_id = stat_buff->st_gid; /* use file group */
if (PERM_FILE == target_type)
*perm = stat_buff->st_mode & 0660; /* use file permissions, masked for user/group read/write */
if (PERM_IPC == target_type)
*perm = 0660; /* read/write for user/group - all readers need write for ipc */
} else
{
if (opener_is_file_owner && !opener_in_file_group)
{
if (gtm_group_restricted)
{
*group_id = lib_gid; /* use restricted group */
assert(gtm_member_group_id(process_uid, *group_id));
if (PERM_FILE == target_type)
*perm = 0660; /* user/group read/write */
if (PERM_IPC == target_type)
*perm = 0660; /* read/write for user/group - all readers need write for ipc */
} else
{
/* use default group */
if (PERM_FILE == target_type)
*perm = 0666; /* read/write for all */
else if (PERM_IPC == target_type)
*perm = 0666; /* read/write for all - all readers need write for ipc */
}
} else if (!opener_is_file_owner && opener_in_file_group)
{
/* opener has access either via file group membership */
if (owner_in_file_group)
{
*group_id = stat_buff->st_gid; /* use file group */
if (PERM_FILE == target_type)
*perm = stat_buff->st_mode & 0660; /* use masked file permissions */
if (PERM_IPC == target_type)
*perm = 0660; /* read/write for user/group - all readers need write for ipc */
} else if (gtm_group_restricted)
{
*group_id = lib_gid; /* use restricted group */
assert(gtm_member_group_id(process_uid, *group_id));
if (PERM_FILE == target_type)
*perm = 0660; /* user/group read/write */
if (PERM_IPC == target_type)
*perm = 0660; /* read/write for user/group - all readers need write for ipc */
} else
{
*group_id = stat_buff->st_gid; /* use file group */
if (PERM_FILE == target_type)
*perm = 0666; /* read/write for all - ensure file owner read/write access */
else if (PERM_IPC == target_type)
*perm = 0666; /* read/write for all - all readers need write for ipc */
}
}
}
}
/* if we never set *perm, return error value */
if (*perm == 0)
{
/* populate perm diag data */
pdd->process_uid = process_uid;
pdd->process_gid = process_gid;
pdd->file_uid = stat_buff->st_uid;
pdd->file_gid = stat_buff->st_gid;
SNPRINTF(pdd->file_perm, SIZEOF(pdd->file_perm), "%04o", stat_buff->st_mode & 07777);
pdd->lib_gid = dist_stat_buff.st_gid;
SNPRINTF(pdd->lib_perm, SIZEOF(pdd->lib_perm), "%04o", dist_stat_buff.st_mode & 07777);
pdd->opener_in_file_group = opener_in_file_group;
pdd->owner_in_file_group = owner_in_file_group;
return -1;
} else
return 0;
}
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