* Licensed under the GPL v2. For licencing details see COPYING.
*/
-/** \file user.c uid User and user ID handling. */
+/** \file user.c \brief User and user ID handling. */
#include "adu.h"
#include <dirent.h> /* readdir() */
uint32_t high;
};
+/** Iterate over all uid ranges. */
#define FOR_EACH_UID_RANGE(ur, urs) for (ur = urs; ur->low <= ur->high; ur++)
/** Flags for the user hash table. */
/** Whether this uid should be taken into account. */
UI_FL_ADMISSIBLE = 2,
};
+
/*
* Contains info for each user that owns at least one regular file.
*
static uint32_t uid_hash_table_size;
/** The number of used slots in the hash table. */
-static uint32_t num_uids = 0;
+static uint32_t num_uids;
/*
* The columns of the per-user tables.
return ret;
}
+/**
+ * Convert the --uid argument to an array of uid ranges.
+ *
+ * \param orig_arg The argument to the --uid option.
+ * \param ur Result pointer.
+ *
+ * Returns Negative on errors. On success, the number of uid ranges
+ * is returned.
+ */
int parse_uid_arg(const char *orig_arg, struct uid_range **ur)
{
char *arg, **argv;
return ret;
}
+/**
+ * Add each given user to the array of admissible users.
+ *
+ * \param users Array of user names to add.
+ * \param num_users Length of \a users.
+ * \param admissible_uids The users which are already admissible.
+ * \param num_uid_ranges The number of intervals of \a admissible_uids.
+ *
+ * For each given user, the function checks whether that user is already
+ * admissible, i.e. its uid is contained in one of the ranges given by \a
+ * admissible_uids. If it is, the function ignores that user. Otherwise, a new
+ * length-one range consisting of that uid only is appended to \a
+ * admissible_uids.
+ *
+ * \return Negative on errors, the new number of uid ranges on success.
+ */
int append_users(char **users, int num_users,
struct uid_range **admissible_uids, int num_uid_ranges)
{
if (pw && pw->pw_name)
ui->pw_name = adu_strdup(pw->pw_name);
- DEBUG_LOG("opening table for uid %u\n", (unsigned)ui->uid);
+ INFO_LOG("opening table for uid %u\n", (unsigned)ui->uid);
if (create) {
ret = osl(osl_create_table(ui->desc));
if (ret < 0)
return ret;
}
+/** Iterate over each user in the uid hash table. */
#define FOR_EACH_USER(ui) for (ui = uid_hash_table; ui < \
uid_hash_table + uid_hash_table_size; ui++)
+
+/**
+ * Execute the given function for each admissible user.
+ *
+ * \param func The function to execute.
+ * \param data Arbitrary pointer.
+ *
+ * This function calls \a func for each admissible user in the uid hash table.
+ * The \a data pointer is passed as the second argument to \a func.
+ *
+ * \return As soon as \a func returns a negative value, the loop is terminated
+ * and that negative value is returned. Otherwise, the function returns 1.
+ */
int for_each_admissible_user(int (*func)(struct user_info *, void *),
void *data)
{
- struct user_info *ui;
+ int i;
assert(uid_hash_table);
- FOR_EACH_USER(ui) {
+ for (i = 0; i < uid_hash_table_size; i++) {
int ret;
+ struct user_info *ui = uid_hash_table + i;
if (!ui_used(ui) || !ui_admissible(ui))
continue;
return 1;
}
+/** Prime number used for calculating the slot for an uid. */
#define PRIME1 0xb11924e1
+/** Prime number used for probe all slots. */
#define PRIME2 0x01000193
+/**
+ * Create a hash table large enough of given size.
+ *
+ * \param bits Sets the maximal number of hash table entries to ^bits.
+ */
void create_hash_table(unsigned bits)
{
uid_hash_table_size = 1 << bits;
sizeof(struct user_info));
}
+/**
+ * Close all open user tables and destroy the uid hash table.
+ *
+ * For each used slot in the uid hash table, close the osl user table if it is
+ * open. Finally, free the uid hash table.
+ */
void close_user_tables(void)
{
struct user_info *ui;
continue;
if (!ui->table)
continue;
- DEBUG_LOG("closing user table for uid %u\n", (unsigned)ui->uid);
+ INFO_LOG("closing user table for uid %u\n", (unsigned)ui->uid);
ret = osl(osl_close_table(ui->table, OSL_MARK_CLEAN));
if (ret < 0)
ERROR_LOG("failed to close user table %u: %s\n",
/*
* We use a hash table of size s=2^uid_hash_bits to map the uids into the
- * interval [0..s]. Hash collisions are treated by open addressing, i.e.
+ * interval [0..s-1]. Hash collisions are treated by open addressing, i.e.
* unused slots in the table are used to store different uids that hash to the
* same slot.
*
* An odd number is sufficient to make sure each entry of the hash table gets
* probed for probe_num between 0 and s-1 because s is a power of two, hence
* the second hash value has never a common divisor with the hash table size.
- * IOW: h is invertible in the ring [0..s].
+ * IOW: h is invertible in the ring [0..s-1].
*/
static uint32_t double_hash(uint32_t uid, uint32_t probe_num)
{
return NULL;
}
+/**
+ * Create and open a osl table for the given uid.
+ *
+ * \param uid The user ID.
+ * \param ui_ptr Result pointer
+ *
+ * Find out whether \a uid already exists in the uid hash table. If yes, just
+ * return the user info struct via \a ui_ptr. Otherwise, insert \a uid into the
+ * uid hash table, create and open the osl user table and also return the user
+ * info struct via \a ui_ptr.
+ *
+ * \return Standard.
+ */
int create_user_table(uint32_t uid, struct user_info **ui_ptr)
{
struct user_info *ui = lookup_uid(uid);
{
return make_message("%s/uid_list", conf.database_dir_arg);
}
-
-void sort_hash_table(int (*comp)(const void *, const void *))
+/**
+ * Open the osl tables for all admissible uids.
+ *
+ * \param admissible_uids Determines which uids are considered admissible.
+ *
+ * Each slot in the hash table contains, among other information, a bit which
+ * specifies whether the uid of the slot is admissible in the current context.
+ *
+ * This function iterates over all entries in the hash table and checks for
+ * each used slot whether the corresponding uid is admissible with respect to
+ * \a admissible_uids. If so, it sets the admissible bit for this slot and
+ * opens the osl table of the uid.
+ *
+ * \return Stamdard.
+ */
+int open_admissible_user_tables(struct uid_range *admissible_uids)
{
- qsort(uid_hash_table, uid_hash_table_size, sizeof(struct user_info),
- comp);
+ struct user_info *ui;
+
+ assert(uid_hash_table);
+ DEBUG_LOG("size: %d\n", uid_hash_table_size);
+ FOR_EACH_USER(ui) {
+ int ret;
+
+ if (!ui_used(ui))
+ continue;
+ if (!uid_is_admissible(ui->uid, admissible_uids)) {
+ DEBUG_LOG("uid %u is not admissible\n", ui->uid);
+ ui->flags &= ~UI_FL_ADMISSIBLE;
+ continue;
+ }
+ ui->flags |= UI_FL_ADMISSIBLE;
+ if (ui->table)
+ continue;
+ ret = open_user_table(ui, 0);
+ if (ret < 0)
+ return ret;
+ }
+ return 1;
}
-int read_uid_file(struct uid_range *admissible_uids)
+/**
+ * Read the file of all possible uids.
+ *
+ * This is called from select/interactive mode. First a large hash table, large
+ * enough to store all uids contained in the uid file is created. Next, the
+ * uids are read from the uid file which was created during the creation of the
+ * database and each uid is inserted into the hash table.
+ *
+ * \sa write_uid_file().
+ *
+ * \return Standard.
+ */
+int read_uid_file(void)
{
size_t size;
uint32_t n;
assert(ui);
if (ui_used(ui)) { /* impossible */
ERROR_LOG("duplicate user id!?\n");
- ret =-EFAULT;
+ ret = -EFAULT;
goto out;
}
ui->uid = uid;
ui->flags |= UI_FL_SLOT_USED;
- if (!uid_is_admissible(uid, admissible_uids))
- continue;
- ui->flags |= UI_FL_ADMISSIBLE;
- ret = open_user_table(ui, 0);
- if (ret < 0)
- return ret;
}
ret = 1;
out:
return ret;
}
+/**
+ * Write the list of uids to permanent storage.
+ *
+ * This is called from create mode after the dir table and all uer tables have
+ * been created. The file simply contains the list of all uids that own at
+ * least one regular file in the base directory and hence an osl table for this
+ * uid exists.
+ *
+ * \sa read_uid_file().
+ *
+ * \return Standard.
+ */
int write_uid_file(void)
{
char *buf, *p, *filename;
projects / adu.git / blobdiff