Port pwcache.c from NetBSD
MODIFY
lib/libc/gen/pwcache.c
lib/libc/gen/pwcache.c
-#include <pwd.h>
+/*-
+ * Copyright (c) 1992 Keith Muller.
+ * Copyright (c) 1992, 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Keith Muller of the University of California, San Diego.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+/*-
+ * Copyright (c) 2002 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+#include <sys/types.h>
+#include <sys/param.h>
+
+#include <assert.h>
#include <grp.h>
+#include <pwd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "pwcache.h"
+
+/*
+ * routines that control user, group, uid and gid caches (for the archive
+ * member print routine).
+ * IMPORTANT:
+ * these routines cache BOTH hits and misses, a major performance improvement
+ */
+
+/*
+ * function pointers to various name lookup routines.
+ * these may be changed as necessary.
+ */
+static int (*_pwcache_setgroupent)(int) = setgroupent;
+static void (*_pwcache_endgrent)(void) = endgrent;
+static struct group *(*_pwcache_getgrnam)(const char *) = getgrnam;
+static struct group *(*_pwcache_getgrgid)(gid_t) = getgrgid;
+static int (*_pwcache_setpassent)(int) = setpassent;
+static void (*_pwcache_endpwent)(void) = endpwent;
+static struct passwd *(*_pwcache_getpwnam)(const char *) = getpwnam;
+static struct passwd *(*_pwcache_getpwuid)(uid_t) = getpwuid;
+
+/*
+ * internal state
+ */
+static int pwopn; /* is password file open */
+static int gropn; /* is group file open */
+static UIDC **uidtb; /* uid to name cache */
+static GIDC **gidtb; /* gid to name cache */
+static UIDC **usrtb; /* user name to uid cache */
+static GIDC **grptb; /* group name to gid cache */
+
+static int uidtb_fail; /* uidtb_start() failed ? */
+static int gidtb_fail; /* gidtb_start() failed ? */
+static int usrtb_fail; /* usrtb_start() failed ? */
+static int grptb_fail; /* grptb_start() failed ? */
+
+static u_int st_hash(const char *, size_t, int);
+static int uidtb_start(void);
+static int gidtb_start(void);
+static int usrtb_start(void);
+static int grptb_start(void);
+
+static u_int st_hash(const char *name, size_t len, int tabsz) {
+ u_int key = 0;
+
+ _DIAGASSERT(name != NULL);
+
+ while (len--) {
+ key += *name++;
+ key = (key << 8) | (key >> 24);
+ }
+
+ return (key % tabsz);
+}
+
+/*
+ * uidtb_start
+ * creates an empty uidtb
+ * Return:
+ * 0 if ok, -1 otherwise
+ */
+static int uidtb_start(void) {
+
+ if (uidtb != NULL)
+ return (0);
+ if (uidtb_fail)
+ return (-1);
+ if ((uidtb = (UIDC **)calloc(UID_SZ, sizeof(UIDC *))) == NULL) {
+ ++uidtb_fail;
+ return (-1);
+ }
+ return (0);
+}
+/*
+ * gidtb_start
+ * creates an empty gidtb
+ * Return:
+ * 0 if ok, -1 otherwise
+ */
+static int gidtb_start(void) {
+
+ if (gidtb != NULL)
+ return (0);
+ if (gidtb_fail)
+ return (-1);
+ if ((gidtb = (GIDC **)calloc(GID_SZ, sizeof(GIDC *))) == NULL) {
+ ++gidtb_fail;
+ return (-1);
+ }
+ return (0);
+}
+
+/*
+ * usrtb_start
+ * creates an empty usrtb
+ * Return:
+ * 0 if ok, -1 otherwise
+ */
+static int usrtb_start(void) {
+
+ if (usrtb != NULL)
+ return (0);
+ if (usrtb_fail)
+ return (-1);
+ if ((usrtb = (UIDC **)calloc(UNM_SZ, sizeof(UIDC *))) == NULL) {
+ ++usrtb_fail;
+ return (-1);
+ }
+ return (0);
+}
+
+/*
+ * grptb_start
+ * creates an empty grptb
+ * Return:
+ * 0 if ok, -1 otherwise
+ */
+static int grptb_start(void) {
+
+ if (grptb != NULL)
+ return (0);
+ if (grptb_fail)
+ return (-1);
+ if ((grptb = (GIDC **)calloc(GNM_SZ, sizeof(GIDC *))) == NULL) {
+ ++grptb_fail;
+ return (-1);
+ }
+ return (0);
+}
+
+/*
+ * user_from_uid()
+ * caches the name (if any) for the uid. If noname clear, we always
+ * return the stored name (if valid or invalid match).
+ * We use a simple hash table.
+ * Return
+ * Pointer to stored name (or a empty string)
+ */
const char *user_from_uid(uid_t uid, int noname) {
- return NULL;
+ struct passwd *pw;
+ UIDC *ptr, **pptr;
+
+ if ((uidtb == NULL) && (uidtb_start() < 0))
+ return (NULL);
+
+ /*
+ * see if we have this uid cached
+ */
+ pptr = uidtb + (uid % UID_SZ);
+ ptr = *pptr;
+
+ if ((ptr != NULL) && (ptr->valid > 0) && (ptr->uid == uid)) {
+ /*
+ * have an entry for this uid
+ */
+ if (!noname || (ptr->valid == VALID))
+ return (ptr->name);
+ return (NULL);
}
+ /*
+ * No entry for this uid, we will add it
+ */
+ if (!pwopn) {
+ if (_pwcache_setpassent != NULL)
+ (*_pwcache_setpassent)(1);
+ ++pwopn;
+ }
+
+ if (ptr == NULL)
+ *pptr = ptr = (UIDC *)malloc(sizeof(UIDC));
+
+ if ((pw = (*_pwcache_getpwuid)(uid)) == NULL) {
+ /*
+ * no match for this uid in the local password file
+ * a string that is the uid in numeric format
+ */
+ if (ptr == NULL)
+ return (NULL);
+ ptr->uid = uid;
+ (void)snprintf(ptr->name, UNMLEN, "%lu", (long)uid);
+ ptr->valid = INVALID;
+ if (noname)
+ return (NULL);
+ } else {
+ /*
+ * there is an entry for this uid in the password file
+ */
+ if (ptr == NULL)
+ return (pw->pw_name);
+ ptr->uid = uid;
+ (void)strlcpy(ptr->name, pw->pw_name, UNMLEN);
+ ptr->valid = VALID;
+ }
+ return (ptr->name);
+}
+
+/*
+ * group_from_gid()
+ * caches the name (if any) for the gid. If noname clear, we always
+ * return the stored name (if valid or invalid match).
+ * We use a simple hash table.
+ * Return
+ * Pointer to stored name (or a empty string)
+ */
const char *group_from_gid(gid_t gid, int noname) {
- return NULL;
+ struct group *gr;
+ GIDC *ptr, **pptr;
+
+ if ((gidtb == NULL) && (gidtb_start() < 0))
+ return (NULL);
+
+ /*
+ * see if we have this gid cached
+ */
+ pptr = gidtb + (gid % GID_SZ);
+ ptr = *pptr;
+
+ if ((ptr != NULL) && (ptr->valid > 0) && (ptr->gid == gid)) {
+ /*
+ * have an entry for this gid
+ */
+ if (!noname || (ptr->valid == VALID))
+ return (ptr->name);
+ return (NULL);
+ }
+
+ /*
+ * No entry for this gid, we will add it
+ */
+ if (!gropn) {
+ if (_pwcache_setgroupent != NULL)
+ (*_pwcache_setgroupent)(1);
+ ++gropn;
+ }
+
+ if (ptr == NULL)
+ *pptr = ptr = (GIDC *)malloc(sizeof(GIDC));
+
+ if ((gr = (*_pwcache_getgrgid)(gid)) == NULL) {
+ /*
+ * no match for this gid in the local group file, put in
+ * a string that is the gid in numberic format
+ */
+ if (ptr == NULL)
+ return (NULL);
+ ptr->gid = gid;
+ (void)snprintf(ptr->name, GNMLEN, "%lu", (long)gid);
+ ptr->valid = INVALID;
+ if (noname)
+ return (NULL);
+ } else {
+ /*
+ * there is an entry for this group in the group file
+ */
+ if (ptr == NULL)
+ return (gr->gr_name);
+ ptr->gid = gid;
+ (void)strlcpy(ptr->name, gr->gr_name, GNMLEN);
+ ptr->valid = VALID;
+ }
+ return (ptr->name);
}
+/*
+ * uid_from_user()
+ * caches the uid for a given user name. We use a simple hash table.
+ * Return
+ * the uid (if any) for a user name, or a -1 if no match can be found
+ */
int uid_from_user(const char *name, uid_t *uid) {
struct passwd *pw;
- pw = getpwnam(name);
- if (pw == NULL)
- return -1;
+ UIDC *ptr, **pptr;
+ size_t namelen;
+ /*
+ * return -1 for mangled names
+ */
+ if (name == NULL || ((namelen = strlen(name)) == 0))
+ return (-1);
+ if ((usrtb == NULL) && (usrtb_start() < 0))
+ return (-1);
+
+ /*
+ * look up in hash table, if found and valid return the uid,
+ * if found and invalid, return a -1
+ */
+ pptr = usrtb + st_hash(name, namelen, UNM_SZ);
+ ptr = *pptr;
+
+ if ((ptr != NULL) && (ptr->valid > 0) && !strcmp(name, ptr->name)) {
+ if (ptr->valid == INVALID)
+ return (-1);
+ *uid = ptr->uid;
+ return (0);
+ }
+
+ if (!pwopn) {
+ if (_pwcache_setpassent != NULL)
+ (*_pwcache_setpassent)(1);
+ ++pwopn;
+ }
+
+ if (ptr == NULL)
+ *pptr = ptr = (UIDC *)malloc(sizeof(UIDC));
+
+ /*
+ * no match, look it up, if no match store it as an invalid entry,
+ * or store the matching uid
+ */
+ if (ptr == NULL) {
+ if ((pw = (*_pwcache_getpwnam)(name)) == NULL)
+ return (-1);
*uid = pw->pw_uid;
- return 0;
+ return (0);
+ }
+ (void)strlcpy(ptr->name, name, UNMLEN);
+ if ((pw = (*_pwcache_getpwnam)(name)) == NULL) {
+ ptr->valid = INVALID;
+ return (-1);
+ }
+ ptr->valid = VALID;
+ *uid = ptr->uid = pw->pw_uid;
+ return (0);
}
+/*
+ * gid_from_group()
+ * caches the gid for a given group name. We use a simple hash table.
+ * Return
+ * the gid (if any) for a group name, or a -1 if no match can be found
+ */
int gid_from_group(const char *name, gid_t *gid) {
struct group *gr;
- gr = getgrnam(name);
- if (gr == NULL)
- return -1;
+ GIDC *ptr, **pptr;
+ size_t namelen;
+
+ /*
+ * return -1 for mangled names
+ */
+ if (name == NULL || ((namelen = strlen(name)) == 0))
+ return (-1);
+ if ((grptb == NULL) && (grptb_start() < 0))
+ return (-1);
+ /*
+ * look up in hash table, if found and valid return the uid,
+ * if found and invalid, return a -1
+ */
+ pptr = grptb + st_hash(name, namelen, GID_SZ);
+ ptr = *pptr;
+
+ if ((ptr != NULL) && (ptr->valid > 0) && !strcmp(name, ptr->name)) {
+ if (ptr->valid == INVALID)
+ return (-1);
+ *gid = ptr->gid;
+ return (0);
+ }
+
+ if (!gropn) {
+ if (_pwcache_setgroupent != NULL)
+ (*_pwcache_setgroupent)(1);
+ ++gropn;
+ }
+
+ if (ptr == NULL)
+ *pptr = ptr = (GIDC *)malloc(sizeof(GIDC));
+
+ /*
+ * no match, look it up, if no match store it as an invalid entry,
+ * or store the matching gid
+ */
+ if (ptr == NULL) {
+ if ((gr = (*_pwcache_getgrnam)(name)) == NULL)
+ return (-1);
*gid = gr->gr_gid;
- return 0;
+ return (0);
+ }
+
+ (void)strlcpy(ptr->name, name, GNMLEN);
+ if ((gr = (*_pwcache_getgrnam)(name)) == NULL) {
+ ptr->valid = INVALID;
+ return (-1);
+ }
+ ptr->valid = VALID;
+ *gid = ptr->gid = gr->gr_gid;
+ return (0);
+}
+
+#define FLUSHTB(arr, len, fail) \
+ do { \
+ if (arr != NULL) { \
+ for (i = 0; i < len; i++) \
+ if (arr[i] != NULL) \
+ free(arr[i]); \
+ arr = NULL; \
+ } \
+ fail = 0; \
+ } while (/* CONSTCOND */ 0);
+
+int pwcache_userdb(int (*a_setpassent)(int), void (*a_endpwent)(void),
+ struct passwd *(*a_getpwnam)(const char *),
+ struct passwd *(*a_getpwuid)(uid_t)) {
+ int i;
+
+ /* a_setpassent and a_endpwent may be NULL */
+ if (a_getpwnam == NULL || a_getpwuid == NULL)
+ return (-1);
+
+ if (_pwcache_endpwent != NULL)
+ (*_pwcache_endpwent)();
+ FLUSHTB(uidtb, UID_SZ, uidtb_fail);
+ FLUSHTB(usrtb, UNM_SZ, usrtb_fail);
+ pwopn = 0;
+ _pwcache_setpassent = a_setpassent;
+ _pwcache_endpwent = a_endpwent;
+ _pwcache_getpwnam = a_getpwnam;
+ _pwcache_getpwuid = a_getpwuid;
+
+ return (0);
+}
+
+int pwcache_groupdb(int (*a_setgroupent)(int), void (*a_endgrent)(void),
+ struct group *(*a_getgrnam)(const char *),
+ struct group *(*a_getgrgid)(gid_t)) {
+ int i;
+
+ /* a_setgroupent and a_endgrent may be NULL */
+ if (a_getgrnam == NULL || a_getgrgid == NULL)
+ return (-1);
+
+ if (_pwcache_endgrent != NULL)
+ (*_pwcache_endgrent)();
+ FLUSHTB(gidtb, GID_SZ, gidtb_fail);
+ FLUSHTB(grptb, GNM_SZ, grptb_fail);
+ gropn = 0;
+ _pwcache_setgroupent = a_setgroupent;
+ _pwcache_endgrent = a_endgrent;
+ _pwcache_getgrnam = a_getgrnam;
+ _pwcache_getgrgid = a_getgrgid;
+
+ return (0);
}

ADD
lib/libc/gen/pwcache.h
+/*-
+ * Copyright (c) 1992 Keith Muller.
+ * Copyright (c) 1992, 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Keith Muller of the University of California, San Diego.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * @(#)cache.h 8.1 (Berkeley) 5/31/93
+ */
+
+/*
+ * Constants and data structures used to implement group and password file
+ * caches. Traditional passwd/group cache routines perform quite poorly with
+ * archives. The chances of hitting a valid lookup with an archive is quite a
+ * bit worse than with files already resident on the file system. These misses
+ * create a MAJOR performance cost. To address this problem, these routines
+ * cache both hits and misses.
+ *
+ * NOTE: name lengths must be as large as those stored in ANY PROTOCOL and
+ * as stored in the passwd and group files. CACHE SIZES MUST BE PRIME
+ */
+#define UNMLEN 32 /* >= user name found in any protocol */
+#define GNMLEN 32 /* >= group name found in any protocol */
+#define UID_SZ 317 /* size of uid to user_name cache */
+#define UNM_SZ 317 /* size of user_name to uid cache */
+#define GID_SZ 251 /* size of gid to group_name cache */
+#define GNM_SZ 251 /* size of group_name to gid cache */
+#define VALID 1 /* entry and name are valid */
+#define INVALID 2 /* entry valid, name NOT valid */
+
+/*
+ * Node structures used in the user, group, uid, and gid caches.
+ */
+
+typedef struct uidc {
+ int valid; /* is this a valid or a miss entry */
+ char name[UNMLEN]; /* uid name */
+ uid_t uid; /* cached uid */
+} UIDC;
+
+typedef struct gidc {
+ int valid; /* is this a valid or a miss entry */
+ char name[GNMLEN]; /* gid name */
+ gid_t gid; /* cached gid */
+} GIDC;

Port pwcache.c from NetBSD (#915)