[prev in list] [next in list] [prev in thread] [next in thread]
List: busybox
Subject: [PATCH] malloced getpw/grxxx functions for bb
From: tito <farmatito () tiscali ! it>
Date: 2014-12-29 21:19:51
Message-ID: 201412292219.51659.farmatito () tiscali ! it
[Download RAW message or body]
On Saturday 06 December 2014 15:24:01 tito wrote:
> On Sunday 09 November 2014 20:56:07 tito wrote:
> > On Sunday 28 September 2014 15:24:50 tito wrote:
> > > On Saturday 27 September 2014 14:58:08 tito wrote:
> > > > On Wednesday 24 September 2014 23:02:55 tito wrote:
> > > > > On Saturday 20 September 2014 16:32:01 tito wrote:
> > > > > > Hi,
> > > > > > One more fix of a return value.
> > > > >
> > > > > Hi,
> > > > > more return value and errno fixes.
> > > > >
> > > > Hi,
> > > > make the tokenize function more robust.
> > > >
> > > Hi,
> > > more minor errno fixes and code cleanups.
> > >
> > Hi,
> > is there anybody bold out there that wants to review
> > this stuff?
> >
> Hi,
> make the parse_common function more robust.
>
Hi,
after putting more work at this malloced libpwdgrp functions I think they now are
pretty robust, with no memory leaks and able to handle more or less gracefully
problematic passwd/group/shadow files. The main features of this
implemantation are:
* 1) the buffer for getpwuid, getgrgid, getpwnam, getgrnam is dynamically
* allocated and reused by later calls. if ERANGE error pops up it is
* reallocated to the size of the longest line found so far in the
* passwd/group files and reused for later calls.
* If ENABLE_FEATURE_CLEAN_UP is set the buffers are freed at program
* exit using the atexit function to make valgrind happy.
* 2) the passwd/group files:
* a) must contain the expected number of fields (as per count of field
* delimeters ":") or we will complain with a error message.
* b) leading or trailing whitespace in fields is allowed and handled.
* c) some fields are not allowed to be empty (e.g. username, uid/gid,
* homedir, shell) and in this case NULL is returned and errno is
* set to EINVAL. This behaviour could be easily changed by
* modifying PW_DEF, GR_DEF, SP_DEF strings (uppercase
* makes a field mandatory).
* d) the string representing uid/gid must be convertible by strtoXX
* functions or NULL is returned and errno is set to EINVAL.
* e) leading or trailing whitespaces in member names and empty members
* are allowed and handled.
* 3) the internal function for getgrouplist uses a dynamically allocated
* buffer and retries with a bigger one in case it is to small;
* 4) the _r functions use the user supplied buffers that are never reallocated
* but use mostly the same common code as the other functions.
* 5) at the moment only the functions really used by busybox code are
* implemented, if you need a particular missing function it should be
* easy to write it by using the internal common code.
I've done some testing and everything seems to work as expected
nonetheless some more testing by the list members and a good
code review by more experienced programmers is needed as this
lib calls stuff is very new for me and maybe I overlooked
something obvious.
Attached you will find a patch and a drop in replacement
for pwd_grp.c for easier review and testing.
Size increase is about 120 bytes due to the increased feature set,
but the bloat-o-meter output looks somewhat suspicious:
./scripts/bloat-o-meter busybox_unstripped_original busybox_unstripped
function old new delta
convert_to_struct - 351 +351
parse_common - 214 +214
tokenize - 136 +136
getgrouplist_internal 185 309 +124
getpw_common - 96 +96
getgr_common - 96 +96
getpw_common_malloc - 78 +78
getgr_common_malloc - 78 +78
parse_file - 75 +75
.rodata 142136 142185 +49
bb_internal_getpwent_r 102 147 +45
my_pwd - 28 +28
my_grp - 16 +16
pwd_buffer_size - 4 +4
pwd_buffer - 4 +4
my_pw - 4 +4
my_gr - 4 +4
grp_buffer_size - 4 +4
grp_buffer - 4 +4
gr_off 3 4 +1
sp_off 9 8 -1
ptr_to_statics 4 - -4
bb_internal_getpwuid 37 19 -18
bb_internal_getspnam_r 119 97 -22
bb_internal_getgrgid 43 19 -24
bb_internal_getpwnam 37 11 -26
get_S 30 - -30
bb_internal_getgrnam 43 11 -32
bb_internal_getpwuid_r 111 - -111
bb_internal_getgrgid_r 111 - -111
bb__parsepwent 112 - -112
bb_internal_getpwnam_r 119 - -119
bb_internal_getgrnam_r 119 - -119
bb__parsespent 124 - -124
bb__pgsreader 194 - -194
bb__parsegrent 246 - -246
------------------------------------------------------------------------------
(add/remove: 16/10 grow/shrink: 4/6 up/down: 1411/-1293) Total: 118 bytes
Critics, hints, improvements are welcome.
Ciao,
Tito
["pwd_grp.patch" (text/x-patch)]
New malloced getpw/grxxx functions for bb.
Signed-off-by: Tito Ragusa <farmatito@tiscali.it>
--- libpwdgrp/pwd_grp.c.original 2014-12-29 21:58:19.059565297 +0100
+++ libpwdgrp/pwd_grp.c 2014-12-29 22:00:18.000000000 +0100
@@ -17,592 +17,579 @@
* large group member lists will cause error returns.
*/
-#include "libbb.h"
-#include <assert.h>
-
-/**********************************************************************/
-/* Sizes for statically allocated buffers. */
-
-#define PWD_BUFFER_SIZE 256
-#define GRP_BUFFER_SIZE 256
-
-/**********************************************************************/
-/* Prototypes for internal functions. */
-
-static int bb__pgsreader(
- int FAST_FUNC (*parserfunc)(void *d, char *line),
- void *data,
- char *__restrict line_buff,
- size_t buflen,
- FILE *f);
+/* Copyright (C) 2014 Tito Ragusa <farmatito@tiscali.it>
+ *
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
+ */
+/* This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY!!
+ *
+ * Rewrite of some parts. Main differences are:
+ *
+ * 1) the buffer for getpwuid, getgrgid, getpwnam, getgrnam is dynamically
+ * allocated and reused by later calls. if ERANGE error pops up it is
+ * reallocated to the size of the longest line found so far in the
+ * passwd/group files and reused for later calls.
+ * If ENABLE_FEATURE_CLEAN_UP is set the buffers are freed at program
+ * exit using the atexit function to make valgrind happy.
+ * 2) the passwd/group files:
+ * a) must contain the expected number of fields (as per count of field
+ * delimeters ":") or we will complain with a error message.
+ * b) leading or trailing whitespace in fields is allowed and handled.
+ * c) some fields are not allowed to be empty (e.g. username, uid/gid,
+ * homedir, shell) and in this case NULL is returned and errno is
+ * set to EINVAL. This behaviour could be easily changed by
+ * modifying PW_DEF, GR_DEF, SP_DEF strings (uppercase
+ * makes a field mandatory).
+ * d) the string representing uid/gid must be convertible by strtoXX
+ * functions or NULL is returned and errno is set to EINVAL.
+ * e) leading or trailing whitespaces in member names and empty members
+ * are allowed and handled.
+ * 3) the internal function for getgrouplist uses a dynamically allocated
+ * buffer and retries with a bigger one in case it is to small;
+ * 4) the _r functions use the user supplied buffers that are never reallocated
+ * but use mostly the same common code as the other functions.
+ * 5) at the moment only the functions really used by busybox code are
+ * implemented, if you need a particular missing function it should be
+ * easy to write it by using the internal common code.
+ */
-static int FAST_FUNC bb__parsepwent(void *pw, char *line);
-static int FAST_FUNC bb__parsegrent(void *gr, char *line);
+#include "libbb.h"
+/* S = string not empty, s = string maybe empty, */
+/* I = uid,gid, l = long maybe empty, m = members,*/
+/* r = reserved */
+#define PW_DEF "SsIIsSS"
+static const char *pw_def = PW_DEF;
+#define _PW_FIELDS sizeof(PW_DEF)-1
+#define GR_DEF "SsIm"
+static const char *gr_def = GR_DEF;
+#define _GR_FIELDS sizeof(GR_DEF)-1
#if ENABLE_USE_BB_SHADOW
-static int FAST_FUNC bb__parsespent(void *sp, char *line);
-#endif
+#define SP_DEF "Ssllllllr"
+static const char *sp_def = SP_DEF;
+#define _SP_FIELDS sizeof(SP_DEF)-1
+#endif
+
+/* Initial buffer size */
+#define PWD_GRP_BUFSIZE 256
+/* for getpw_common_malloc */
+static char *pwd_buffer = NULL;
+static size_t pwd_buffer_size = PWD_GRP_BUFSIZE;
+struct passwd *my_pw;
+struct passwd my_pwd;
+/* for getgr_common_malloc */
+static char *grp_buffer = NULL;
+static size_t grp_buffer_size = PWD_GRP_BUFSIZE;
+struct group *my_gr;
+struct group my_grp;
+/* for setpwent, getpwent_r, endpwent */
+static FILE *pwf = NULL;
+/* for setgrent, getgrent_r, endgrent */
+static FILE *grf = NULL;
+
+/* We do no file locking */
+#define LOCK ((void) 0)
+#define UNLOCK ((void) 0)
/**********************************************************************/
-/* We avoid having big global data. */
-
-struct statics {
- /* Smaller things first */
- /* It's ok to use one buffer for getpwuid and getpwnam. Manpage says:
- * "The return value may point to a static area, and may be overwritten
- * by subsequent calls to getpwent(), getpwnam(), or getpwuid()."
- */
- struct passwd getpw_resultbuf;
- struct group getgr_resultbuf;
-
- char getpw_buffer[PWD_BUFFER_SIZE];
- char getgr_buffer[GRP_BUFFER_SIZE];
-#if 0 //ENABLE_USE_BB_SHADOW
- struct spwd getsp_resultbuf;
- char getsp_buffer[PWD_BUFFER_SIZE];
-#endif
-// Not converted - too small to bother
-//pthread_mutex_t mylock = PTHREAD_MUTEX_INITIALIZER;
-//FILE *pwf /*= NULL*/;
-//FILE *grf /*= NULL*/;
-//FILE *spf /*= NULL*/;
-};
-
-static struct statics *ptr_to_statics;
-
-static struct statics *get_S(void)
-{
- if (!ptr_to_statics)
- ptr_to_statics = xzalloc(sizeof(*ptr_to_statics));
- return ptr_to_statics;
-}
-
-/* Always use in this order, get_S() must be called first */
-#define RESULTBUF(name) &((S = get_S())->name##_resultbuf)
-#define BUFFER(name) (S->name##_buffer)
-
-/**********************************************************************/
-/* For the various fget??ent_r funcs, return
- *
- * 0: success
- * ENOENT: end-of-file encountered
- * ERANGE: buflen too small
- * other error values possible. See bb__pgsreader.
- *
- * Also, *result == resultbuf on success and NULL on failure.
- *
- * NOTE: glibc difference - For the ENOENT case, glibc also sets errno.
- * We do not, as it really isn't an error if we reach the end-of-file.
- * Doing so is analogous to having fgetc() set errno on EOF.
- */
+/* Internal functions */
/**********************************************************************/
-int fgetpwent_r(FILE *__restrict stream, struct passwd *__restrict resultbuf,
- char *__restrict buffer, size_t buflen,
- struct passwd **__restrict result)
+/* Divide the passwd/group/shadow record in fields
+ * by substituting the given delimeter
+ * e.g. ':' or ',' with '\0'.
+ * Returns the number of fields found.
+ * Strips leading or trailing whitespace in fields.
+ */
+static int FAST_FUNC tokenize(char *buffer, int ch)
{
- int rv;
+ char *p = buffer;
+ char *s = p;
+ int num_fields = 1;
- *result = NULL;
-
- rv = bb__pgsreader(bb__parsepwent, resultbuf, buffer, buflen, stream);
- if (!rv) {
- *result = resultbuf;
+ while (*p) {
+ while (isspace(*s)) {
+ memmove(s, s + 1, strlen(s + 1) + 1);
+ }
+ if (*p == ch) {
+ while (p != s && isspace(*(p - 1))) {
+ memmove(p - 1, p, strlen(p) + 1);
+ p = p - 1;
+ }
+ *p = '\0';
+ num_fields++;
+ s = p + 1;
+ }
+ p++;
}
-
- return rv;
+ return num_fields;
}
-int fgetgrent_r(FILE *__restrict stream, struct group *__restrict resultbuf,
- char *__restrict buffer, size_t buflen,
- struct group **__restrict result)
+/* Fill the buffer linebuf up to len with
+ * a line of a passwd/group file.
+ * Returns 0 on success, ENOENT on EOF and
+ * ERANGE if buffer is not big enough,
+ * in the latter case the size needed
+ * is set in size_t *len.
+ */
+static int FAST_FUNC get_record_line(FILE *file, char *linebuf, size_t *len)
{
- int rv;
+ int ch;
+ int idx = 0;
- *result = NULL;
-
- rv = bb__pgsreader(bb__parsegrent, resultbuf, buffer, buflen, stream);
- if (!rv) {
- *result = resultbuf;
+ while ((ch = getc(file)) != EOF) {
+ if (idx < *len) {
+ linebuf[idx] = (char) ch;
+ }
+ idx++;
+ if (ch == '\n' || ch == '\0')
+ break;
}
-
- return rv;
-}
-
-#if ENABLE_USE_BB_SHADOW
-#ifdef UNUSED_FOR_NOW
-int fgetspent_r(FILE *__restrict stream, struct spwd *__restrict resultbuf,
- char *__restrict buffer, size_t buflen,
- struct spwd **__restrict result)
+ if (idx > *len) {
+ *len = idx;
+ return ERANGE;
+ }
+ /* return ENOENT only on EOF and no data */
+ if (idx > 0) {
+ /* terminate string and remove trailing '\n' if any.*/
+ linebuf[idx - 1] = '\0';
+ return 0;
+ }
+ return ENOENT;
+}
+
+/* Returns 0 on success and matching line broken up in fields by '\0' in buf or
+ * error. We require the expected number of fields to be found.
+ * size_t *len is used to check that the buffer provided is big enough, if not
+ * we reuse size_t *len to pass the needed length to the caller.
+ */
+static int FAST_FUNC parse_common(FILE *f, const char *key, int field_pos,
+ char *buf, size_t *len, const char *filename, int n_fields)
{
- int rv;
-
- *result = NULL;
-
- rv = bb__pgsreader(bb__parsespent, resultbuf, buffer, buflen, stream);
- if (!rv) {
- *result = resultbuf;
+ int count = 0;
+ int error;
+ const char *s;
+
+ while ((error = get_record_line(f, buf, len)) == 0) {
+ count++;
+ /* Skip empty lines, comment lines */
+ if (buf[0] != '\0' && buf[0] != '#') {
+ if (tokenize(buf, ':') == n_fields) {
+ if (field_pos >= 0) {
+ if (*(s = nth_string(buf, field_pos))) {
+ if (key && *key) {
+ if (strcmp(key, s) == 0) {
+ /* record found */
+ break;
+ }
+ } /* else skip: caller passed bad key */
+ } /* else skip: field is empty */
+ } /*else skip: the field we look for doesn't exist */
+ if (field_pos < 0) {
+ /* No field specified: sequential read, return a record */
+ break;
+ }
+ } else {
+ /* number of fields is wrong */
+ bb_error_msg("%s: bad record at line %d", filename, count);
+ }
+ }
}
-
- return rv;
+ return error;
}
-#endif
-#endif
-/**********************************************************************/
-/* For the various fget??ent funcs, return NULL on failure and a
- * pointer to the appropriate struct (statically allocated) on success.
- * TODO: audit & stop using these in bbox, they pull in static buffers */
-/**********************************************************************/
-
-#ifdef UNUSED_SINCE_WE_AVOID_STATIC_BUFS
-struct passwd *fgetpwent(FILE *stream)
+static int FAST_FUNC parse_file(const char *filename, int n_fields,
+ const char *key, int field_pos, char *buf, size_t *len)
{
- struct statics *S;
- struct passwd *resultbuf = RESULTBUF(getpw);
- char *buffer = BUFFER(getpw);
- struct passwd *result;
+ FILE *f = fopen_for_read(filename);
+ int ret = errno;
- fgetpwent_r(stream, resultbuf, buffer, sizeof(BUFFER(getpw)), &result);
- return result;
+ if (f) {
+ ret = parse_common(f, key, field_pos, buf, len, filename, n_fields);
+ fclose(f);
+ }
+ return ret;
}
-struct group *fgetgrent(FILE *stream)
+/* Convert passwd/group/shadow file record in buffer to a struct */
+static void * FAST_FUNC convert_to_struct(const char *def,
+ const unsigned char *off, char *buffer,
+ void *result, int *error)
{
- struct statics *S;
- struct group *resultbuf = RESULTBUF(getgr);
- char *buffer = BUFFER(getgr);
- struct group *result;
-
- fgetgrent_r(stream, resultbuf, buffer, sizeof(BUFFER(getgr)), &result);
- return result;
-}
-#endif
+ int idx;
+ long ret;
+ char *m;
+ char **members = NULL;
+ for (idx = 0; def[idx] != '\0'; idx++) {
+ if (def[idx] == 'S' || def[idx] == 's') {
+ m = (char *) nth_string(buffer, idx);
+ *(char **)((char *)result + off[idx]) = m;
+ if (!*m && (def[idx] == 'S')) {
+ *error = EINVAL;
+ }
+ }
+ if (def[idx] == 'I') {
+ m = (char *) nth_string(buffer, idx);
+ *(int *)((int) result + off[idx]) = bb_strtou(m, NULL, 10);
+ if (errno) {
+ *error = EINVAL;
+ }
+ }
#if ENABLE_USE_BB_SHADOW
-#ifdef UNUSED_SINCE_WE_AVOID_STATIC_BUFS
-struct spwd *fgetspent(FILE *stream)
-{
- struct statics *S;
- struct spwd *resultbuf = RESULTBUF(getsp);
- char *buffer = BUFFER(getsp);
- struct spwd *result;
-
- fgetspent_r(stream, resultbuf, buffer, sizeof(BUFFER(getsp)), &result);
- return result;
-}
-#endif
+ if (def[idx] == 'l') {
+ char *endptr;
-#ifdef UNUSED_FOR_NOW
-int sgetspent_r(const char *string, struct spwd *result_buf,
- char *buffer, size_t buflen, struct spwd **result)
-{
- int rv = ERANGE;
-
- *result = NULL;
-
- if (buflen < PWD_BUFFER_SIZE) {
- DO_ERANGE:
- errno = rv;
- goto DONE;
- }
+ m = (char *) nth_string(buffer, idx);
+ ret = bb_strtol(m, &endptr, 10);
+ if (endptr == m) {
+ ret = -1L;
+ } else if (errno) {
+ *error = EINVAL;
+ }
+ *(long *)((long) result + off[idx]) = ret;
+ }
+#endif
+ if (def[idx] == 'm') {
+ char *s = (char *) nth_string(buffer, idx);
+ int i = tokenize(s, ',');
+ char *p = (char *) nth_string(s, i);
+ /* Now align (p+1), rounding up. */
+ /* Assumes sizeof(char **) is a power of 2. */
+ members = (char **)((((intptr_t) p) + sizeof(char **))
+ & ~((intptr_t)(sizeof(char **) - 1)));
- if (string != buffer) {
- if (strlen(string) >= buflen) {
- goto DO_ERANGE;
+ ((struct group *) result)->gr_mem = members;
+ /* Pointing to char prior to first member. */
+ p = s - 1;
+ while (1) {
+ if (*(p + 1))
+ *members++ = ++p;
+ if (!--i)
+ break;
+ while (*++p)
+ continue;
+ }
+ *members = NULL;
}
- strcpy(buffer, string);
}
-
- rv = bb__parsespent(result_buf, buffer);
- if (!rv) {
- *result = result_buf;
+ if (*error) {
+ result = NULL;
+ errno = *error;
}
-
- DONE:
- return rv;
+ return result;
}
-#endif
-#endif /* ENABLE_USE_BB_SHADOW */
-
-/**********************************************************************/
-
-#define GETXXKEY_R_FUNC getpwnam_r
-#define GETXXKEY_R_PARSER bb__parsepwent
-#define GETXXKEY_R_ENTTYPE struct passwd
-#define GETXXKEY_R_TEST(ENT) (!strcmp((ENT)->pw_name, key))
-#define GETXXKEY_R_KEYTYPE const char *__restrict
-#define GETXXKEY_R_PATHNAME _PATH_PASSWD
-#include "pwd_grp_internal.c"
-
-#define GETXXKEY_R_FUNC getgrnam_r
-#define GETXXKEY_R_PARSER bb__parsegrent
-#define GETXXKEY_R_ENTTYPE struct group
-#define GETXXKEY_R_TEST(ENT) (!strcmp((ENT)->gr_name, key))
-#define GETXXKEY_R_KEYTYPE const char *__restrict
-#define GETXXKEY_R_PATHNAME _PATH_GROUP
-#include "pwd_grp_internal.c"
#if ENABLE_USE_BB_SHADOW
-#define GETXXKEY_R_FUNC getspnam_r
-#define GETXXKEY_R_PARSER bb__parsespent
-#define GETXXKEY_R_ENTTYPE struct spwd
-#define GETXXKEY_R_TEST(ENT) (!strcmp((ENT)->sp_namp, key))
-#define GETXXKEY_R_KEYTYPE const char *__restrict
-#define GETXXKEY_R_PATHNAME _PATH_SHADOW
-#include "pwd_grp_internal.c"
-#endif
-
-#define GETXXKEY_R_FUNC getpwuid_r
-#define GETXXKEY_R_PARSER bb__parsepwent
-#define GETXXKEY_R_ENTTYPE struct passwd
-#define GETXXKEY_R_TEST(ENT) ((ENT)->pw_uid == key)
-#define GETXXKEY_R_KEYTYPE uid_t
-#define GETXXKEY_R_PATHNAME _PATH_PASSWD
-#include "pwd_grp_internal.c"
-
-#define GETXXKEY_R_FUNC getgrgid_r
-#define GETXXKEY_R_PARSER bb__parsegrent
-#define GETXXKEY_R_ENTTYPE struct group
-#define GETXXKEY_R_TEST(ENT) ((ENT)->gr_gid == key)
-#define GETXXKEY_R_KEYTYPE gid_t
-#define GETXXKEY_R_PATHNAME _PATH_GROUP
-#include "pwd_grp_internal.c"
-
-/**********************************************************************/
-/* TODO: audit & stop using these in bbox, they pull in static buffers */
+static const unsigned char sp_off[] ALIGN1 = {
+ offsetof(struct spwd, sp_namp), /* 1 - Login name */
+ offsetof(struct spwd, sp_pwdp), /* 2 - Encrypted password */
+ offsetof(struct spwd, sp_lstchg), /* 2 - not a char ptr */
+ offsetof(struct spwd, sp_min), /* 3 - not a char ptr */
+ offsetof(struct spwd, sp_max), /* 4 - not a char ptr */
+ offsetof(struct spwd, sp_warn), /* 5 - not a char ptr */
+ offsetof(struct spwd, sp_inact), /* 6 - not a char ptr */
+ offsetof(struct spwd, sp_expire) /* 7 - not a char ptr */
+// ,offsetof(struct spwd, sp_flag) /* 8 - Reserved */
+};
-/* This one has many users */
-struct passwd *getpwuid(uid_t uid)
+int getspnam_r(const char *name, struct spwd *spbuf, char *buf, size_t buflen,
+ struct spwd **spbufp)
{
- struct statics *S;
- struct passwd *resultbuf = RESULTBUF(getpw);
- char *buffer = BUFFER(getpw);
- struct passwd *result;
-
- getpwuid_r(uid, resultbuf, buffer, sizeof(BUFFER(getpw)), &result);
- return result;
+ int error;
+ size_t len = buflen;
+
+ *spbufp = NULL;
+ error = parse_file(_PATH_SHADOW, _SP_FIELDS, name, 0, buf, &len);
+ if (error == 0) {
+ *spbufp = convert_to_struct(sp_def, sp_off, buf, spbuf, &error);
+ }
+ return error;
}
+#endif /* ENABLE_USE_BB_SHADOW */
-/* This one has many users */
-struct group *getgrgid(gid_t gid)
-{
- struct statics *S;
- struct group *resultbuf = RESULTBUF(getgr);
- char *buffer = BUFFER(getgr);
- struct group *result;
+static const unsigned char pw_off[] ALIGN1 = {
+ offsetof(struct passwd, pw_name), /* 0 */
+ offsetof(struct passwd, pw_passwd), /* 1 */
+ offsetof(struct passwd, pw_uid), /* 2 - not a char ptr */
+ offsetof(struct passwd, pw_gid), /* 3 - not a char ptr */
+ offsetof(struct passwd, pw_gecos), /* 4 */
+ offsetof(struct passwd, pw_dir), /* 5 */
+ offsetof(struct passwd, pw_shell) /* 6 */
+};
- getgrgid_r(gid, resultbuf, buffer, sizeof(BUFFER(getgr)), &result);
- return result;
-}
+static const unsigned char gr_off[] ALIGN1 = {
+ offsetof(struct group, gr_name), /* 0 */
+ offsetof(struct group, gr_passwd), /* 1 */
+ offsetof(struct group, gr_gid), /* 2 - not a char ptr */
+ offsetof(struct group, gr_mem) /* 3 - char ** ptr */
+};
-#if 0 //ENABLE_USE_BB_SHADOW
-/* This function is non-standard and is currently not built. It seems
- * to have been created as a reentrant version of the non-standard
- * functions getspuid. Why getspuid was added, I do not know. */
-int getspuid_r(uid_t uid, struct spwd *__restrict resultbuf,
- char *__restrict buffer, size_t buflen,
- struct spwd **__restrict result)
-{
- int rv;
- struct passwd *pp;
- struct passwd password;
- char pwd_buff[PWD_BUFFER_SIZE];
+/* Common code for getpwxxx/_r functions. */
+static int FAST_FUNC getpw_common(const char *name, int field,
+ struct passwd *pwd, char *buf, size_t *buflen,
+ struct passwd **result)
+{
+ int error;
*result = NULL;
- rv = getpwuid_r(uid, &password, pwd_buff, sizeof(pwd_buff), &pp);
- if (!rv) {
- rv = getspnam_r(password.pw_name, resultbuf, buffer, buflen, result);
+ error = parse_file(_PATH_PASSWD, _PW_FIELDS, name, field, buf, buflen);
+ if (error == 0) {
+ *result = convert_to_struct(pw_def, pw_off, buf, pwd, &error);
}
-
- return rv;
+ return (error == ENOENT) ? 0 : error;
}
-/* This function is non-standard and is currently not built.
- * Why it was added, I do not know. */
-struct spwd *getspuid(uid_t uid)
+/* Common code for getgrxxx/_r functions. */
+static int FAST_FUNC getgr_common(const char *name, int field,
+ struct group *grp, char *buf, size_t *buflen,
+ struct group **result)
{
- struct statics *S;
- struct spwd *resultbuf = RESULTBUF(getsp);
- char *buffer = BUFFER(getsp);
- struct spwd *result;
+ int error;
- getspuid_r(uid, resultbuf, buffer, sizeof(BUFFER(getsp)), &result);
- return result;
+ *result = NULL;
+ error = parse_file(_PATH_GROUP, _GR_FIELDS, name, field, buf, buflen);
+ if (error == 0) {
+ *result = convert_to_struct(gr_def, gr_off, buf, grp, &error);
+ }
+ return (error == ENOENT) ? 0 : error;
}
-#endif
-/* This one has many users */
-struct passwd *getpwnam(const char *name)
+#if ENABLE_FEATURE_CLEAN_UP
+static void FAST_FUNC free_pwd(void)
{
- struct statics *S;
- struct passwd *resultbuf = RESULTBUF(getpw);
- char *buffer = BUFFER(getpw);
- struct passwd *result;
-
- getpwnam_r(name, resultbuf, buffer, sizeof(BUFFER(getpw)), &result);
- return result;
+ free(pwd_buffer);
}
-
-/* This one has many users */
-struct group *getgrnam(const char *name)
+#endif
+/* Common code for getpwxxx functions. */
+static struct passwd * FAST_FUNC getpw_common_malloc(const char *name, int field)
{
- struct statics *S;
- struct group *resultbuf = RESULTBUF(getgr);
- char *buffer = BUFFER(getgr);
- struct group *result;
-
- getgrnam_r(name, resultbuf, buffer, sizeof(BUFFER(getgr)), &result);
- return result;
+ int error = 0;
+#if ENABLE_FEATURE_CLEAN_UP
+ if (pwd_buffer == NULL) {
+ atexit(free_pwd);
+ }
+#endif
+retry:
+ pwd_buffer = xrealloc(pwd_buffer, pwd_buffer_size * sizeof(char));
+ error = getpw_common(name, field, &my_pwd, pwd_buffer, &pwd_buffer_size, &my_pw);
+ if (error == ERANGE) {
+ errno = 0;
+ goto retry;
+ }
+ return my_pw;
}
-#if 0 //ENABLE_USE_BB_SHADOW
-struct spwd *getspnam(const char *name)
+#if ENABLE_FEATURE_CLEAN_UP
+static void FAST_FUNC free_grp(void)
{
- struct statics *S;
- struct spwd *resultbuf = RESULTBUF(getsp);
- char *buffer = BUFFER(getsp);
- struct spwd *result;
-
- getspnam_r(name, resultbuf, buffer, sizeof(BUFFER(getsp)), &result);
- return result;
+ free(grp_buffer);
}
#endif
-/**********************************************************************/
-
-/* FIXME: we don't have such CONFIG_xx - ?! */
-
-#if defined CONFIG_USE_BB_THREADSAFE_SHADOW && defined PTHREAD_MUTEX_INITIALIZER
-static pthread_mutex_t mylock = PTHREAD_MUTEX_INITIALIZER;
-# define LOCK pthread_mutex_lock(&mylock)
-# define UNLOCK pthread_mutex_unlock(&mylock);
-#else
-# define LOCK ((void) 0)
-# define UNLOCK ((void) 0)
-#endif
-
-static FILE *pwf /*= NULL*/;
-void setpwent(void)
+/* Common code for getgrxxx functions. */
+static struct group * FAST_FUNC getgr_common_malloc(const char *name, int field)
{
- LOCK;
- if (pwf) {
- rewind(pwf);
+ int error = 0;
+#if ENABLE_FEATURE_CLEAN_UP
+ if (grp_buffer == NULL) {
+ atexit(free_grp);
}
- UNLOCK;
-}
-
-void endpwent(void)
-{
- LOCK;
- if (pwf) {
- fclose(pwf);
- pwf = NULL;
+#endif
+retry:
+ grp_buffer = xrealloc(grp_buffer, grp_buffer_size * sizeof(char));
+ error = getgr_common(name, field, &my_grp, grp_buffer, &grp_buffer_size, &my_gr);
+ if (error == ERANGE) {
+ errno = 0;
+ goto retry;
}
- UNLOCK;
+ return my_gr;
}
+/**********************************************************************/
-int getpwent_r(struct passwd *__restrict resultbuf,
- char *__restrict buffer, size_t buflen,
- struct passwd **__restrict result)
+int getpwent_r(struct passwd *pwbuf, char *buf, size_t buflen, struct passwd **pwbufp)
{
- int rv;
+ int error;
+ size_t len = buflen;
LOCK;
- *result = NULL; /* In case of error... */
-
+ *pwbufp = NULL;
if (!pwf) {
pwf = fopen_for_read(_PATH_PASSWD);
if (!pwf) {
- rv = errno;
- goto ERR;
+ return errno;
}
close_on_exec_on(fileno(pwf));
}
-
- rv = bb__pgsreader(bb__parsepwent, resultbuf, buffer, buflen, pwf);
- if (!rv) {
- *result = resultbuf;
- }
-
- ERR:
- UNLOCK;
- return rv;
-}
-
-static FILE *grf /*= NULL*/;
-void setgrent(void)
-{
- LOCK;
- if (grf) {
- rewind(grf);
+ error = parse_common(pwf, NULL, -1, buf, &len, _PATH_PASSWD, _PW_FIELDS);
+ if (error == 0) {
+ *pwbufp = convert_to_struct(pw_def, pw_off, buf, pwbuf, &error);
}
UNLOCK;
-}
-void endgrent(void)
-{
- LOCK;
- if (grf) {
- fclose(grf);
- grf = NULL;
- }
- UNLOCK;
+ return error;
}
-int getgrent_r(struct group *__restrict resultbuf,
- char *__restrict buffer, size_t buflen,
- struct group **__restrict result)
+int getgrent_r(struct group *gbuf, char *buf, size_t buflen, struct group **gbufp)
{
- int rv;
-
+ int error;
+ size_t len = buflen;
+
LOCK;
- *result = NULL; /* In case of error... */
-
+ *gbufp = NULL;
if (!grf) {
grf = fopen_for_read(_PATH_GROUP);
if (!grf) {
- rv = errno;
- goto ERR;
+ return errno;
}
close_on_exec_on(fileno(grf));
}
-
- rv = bb__pgsreader(bb__parsegrent, resultbuf, buffer, buflen, grf);
- if (!rv) {
- *result = resultbuf;
+ error = parse_common(grf, NULL, -1, buf, &len, _PATH_GROUP, _GR_FIELDS);
+ if (error == 0) {
+ *gbufp = convert_to_struct(gr_def, gr_off, buf, gbuf, &error);
}
-
- ERR:
UNLOCK;
- return rv;
+
+ return error;
}
-#ifdef UNUSED_FOR_NOW
-#if ENABLE_USE_BB_SHADOW
-static FILE *spf /*= NULL*/;
-void setspent(void)
+int getpwnam_r(const char *name, struct passwd *pwd, char *buf, size_t buflen,
+ struct passwd **result)
{
- LOCK;
- if (spf) {
- rewind(spf);
- }
- UNLOCK;
+ size_t len = buflen;
+
+ return getpw_common(name, 0, pwd, buf, &len, result);
}
-void endspent(void)
+int getgrnam_r(const char *name, struct group *grp, char *buf, size_t buflen,
+ struct group **result)
{
- LOCK;
- if (spf) {
- fclose(spf);
- spf = NULL;
- }
- UNLOCK;
+ size_t len = buflen;
+
+ return getgr_common(name, 0, grp, buf, &len, result);
}
-int getspent_r(struct spwd *resultbuf, char *buffer,
- size_t buflen, struct spwd **result)
+int getpwuid_r(uid_t uid, struct passwd *pwd, char *buf, size_t buflen,
+ struct passwd **result)
{
- int rv;
-
- LOCK;
- *result = NULL; /* In case of error... */
+ size_t len = buflen;
- if (!spf) {
- spf = fopen_for_read(_PATH_SHADOW);
- if (!spf) {
- rv = errno;
- goto ERR;
- }
- close_on_exec_on(fileno(spf));
- }
+ return getpw_common(utoa(uid), 2, pwd, buf, &len, result);
+}
- rv = bb__pgsreader(bb__parsespent, resultbuf, buffer, buflen, spf);
- if (!rv) {
- *result = resultbuf;
- }
+int getgrgid_r(gid_t gid, struct group *grp, char *buf, size_t buflen,
+ struct group **result)
+{
+ size_t len = buflen;
- ERR:
- UNLOCK;
- return rv;
+ return getgr_common(utoa(gid), 2, grp, buf, &len, result);
}
-#endif
-#endif /* UNUSED_FOR_NOW */
-#ifdef UNUSED_SINCE_WE_AVOID_STATIC_BUFS
-struct passwd *getpwent(void)
+struct passwd *getpwnam(const char *name)
{
- static char line_buff[PWD_BUFFER_SIZE];
- static struct passwd pwd;
- struct passwd *result;
+ return getpw_common_malloc(name, 0);
+}
- getpwent_r(&pwd, line_buff, sizeof(line_buff), &result);
- return result;
+struct group *getgrnam(const char *name)
+{
+ return getgr_common_malloc(name, 0);
}
-struct group *getgrent(void)
+struct passwd *getpwuid(uid_t uid)
{
- static char line_buff[GRP_BUFFER_SIZE];
- static struct group gr;
- struct group *result;
+ return getpw_common_malloc(utoa(uid), 2);
+}
- getgrent_r(&gr, line_buff, sizeof(line_buff), &result);
- return result;
+struct group *getgrgid(gid_t gid)
+{
+ return getgr_common_malloc(utoa(gid), 2);
}
-#if ENABLE_USE_BB_SHADOW
-struct spwd *getspent(void)
+void endpwent(void)
{
- static char line_buff[PWD_BUFFER_SIZE];
- static struct spwd spwd;
- struct spwd *result;
+ LOCK;
+ if (pwf) {
+ fclose(pwf);
+ pwf = NULL;
+ }
+ UNLOCK;
+}
- getspent_r(&spwd, line_buff, sizeof(line_buff), &result);
- return result;
+void setpwent(void)
+{
+ LOCK;
+ if (pwf) {
+ rewind(pwf);
+ }
+ UNLOCK;
}
-struct spwd *sgetspent(const char *string)
+void endgrent(void)
{
- static char line_buff[PWD_BUFFER_SIZE];
- static struct spwd spwd;
- struct spwd *result;
+ LOCK;
+ if (grf) {
+ fclose(grf);
+ grf = NULL;
+ }
+ UNLOCK;
+}
- sgetspent_r(string, &spwd, line_buff, sizeof(line_buff), &result);
- return result;
+void setgrent(void)
+{
+ LOCK;
+ if (grf) {
+ rewind(grf);
+ }
+ UNLOCK;
}
-#endif
-#endif /* UNUSED_SINCE_WE_AVOID_STATIC_BUFS */
-static gid_t *getgrouplist_internal(int *ngroups_ptr, const char *user, gid_t gid)
+static gid_t * FAST_FUNC getgrouplist_internal(int *ngroups_ptr,
+ const char *user, gid_t gid)
{
- FILE *grfile;
+ FILE *f;
+ struct group *gr;
+ struct group grp;
gid_t *group_list;
int ngroups;
- struct group group;
- char buff[PWD_BUFFER_SIZE];
+ char * buffer = NULL;
+ size_t buflen = PWD_GRP_BUFSIZE;
+ int ret = 0;
- /* We alloc space for 8 gids at a time. */
- group_list = xmalloc(8 * sizeof(group_list[0]));
- group_list[0] = gid;
+retry:
+ group_list = NULL;
ngroups = 1;
-
- grfile = fopen_for_read(_PATH_GROUP);
- if (grfile) {
- while (!bb__pgsreader(bb__parsegrent, &group, buff, sizeof(buff), grfile)) {
- char **m;
- assert(group.gr_mem); /* Must have at least a NULL terminator. */
- if (group.gr_gid == gid)
- continue;
- for (m = group.gr_mem; *m; m++) {
- if (strcmp(*m, user) != 0)
- continue;
- group_list = xrealloc_vector(group_list, /*8=2^3:*/ 3, ngroups);
- group_list[ngroups++] = group.gr_gid;
- break;
+
+ f = fopen_for_read(_PATH_GROUP);
+ if (f) {
+ group_list = xrealloc(group_list, 1 * sizeof(gid_t));
+ *group_list = gid;
+ buffer = xrealloc(buffer, buflen * sizeof( char));
+ while ((ret = parse_common(f, NULL, -1, buffer, &buflen,
+ _PATH_GROUP, _GR_FIELDS)) == 0) {
+ gr = convert_to_struct(gr_def, gr_off, buffer, &grp, &ret);
+ if (gr != NULL) {
+ if (gr->gr_gid != gid) {
+ /* reuse int ret */
+ for (/*ret = 0*/; gr->gr_mem[ret] != NULL; ret++) {
+ if (strcmp(gr->gr_mem[ret], user) == 0) {
+ group_list = xrealloc(group_list,
+ (ngroups + 1) * sizeof(gid_t));
+ group_list[ngroups++] = gr->gr_gid;
+ }
+ }
+ }
}
}
- fclose(grfile);
+ fclose(f);
+ }
+ if (ret == ERANGE) {
+ /* buffer was to small, retry */
+ free(group_list);
+ goto retry;
}
+ free(buffer);
+
*ngroups_ptr = ngroups;
return group_list;
}
@@ -631,409 +618,3 @@ int getgrouplist(const char *user, gid_t
free(group_list);
return ngroups_old;
}
-
-#ifdef UNUSED_SINCE_WE_AVOID_STATIC_BUFS
-int putpwent(const struct passwd *__restrict p, FILE *__restrict f)
-{
- int rv = -1;
-
-#if 0
- /* glibc does this check */
- if (!p || !f) {
- errno = EINVAL;
- return rv;
- }
-#endif
-
- /* No extra thread locking is needed above what fprintf does. */
- if (fprintf(f, "%s:%s:%lu:%lu:%s:%s:%s\n",
- p->pw_name, p->pw_passwd,
- (unsigned long)(p->pw_uid),
- (unsigned long)(p->pw_gid),
- p->pw_gecos, p->pw_dir, p->pw_shell) >= 0
- ) {
- rv = 0;
- }
-
- return rv;
-}
-
-int putgrent(const struct group *__restrict p, FILE *__restrict f)
-{
- int rv = -1;
-
-#if 0
- /* glibc does this check */
- if (!p || !f) {
- errno = EINVAL;
- return rv;
- }
-#endif
-
- if (fprintf(f, "%s:%s:%lu:",
- p->gr_name, p->gr_passwd,
- (unsigned long)(p->gr_gid)) >= 0
- ) {
- static const char format[] ALIGN1 = ",%s";
-
- char **m;
- const char *fmt;
-
- fmt = format + 1;
-
- assert(p->gr_mem);
- m = p->gr_mem;
-
- while (1) {
- if (!*m) {
- if (fputc('\n', f) >= 0) {
- rv = 0;
- }
- break;
- }
- if (fprintf(f, fmt, *m) < 0) {
- break;
- }
- m++;
- fmt = format;
- }
- }
-
- return rv;
-}
-#endif
-
-#if ENABLE_USE_BB_SHADOW
-#ifdef UNUSED_FOR_NOW
-static const unsigned char put_sp_off[] ALIGN1 = {
- offsetof(struct spwd, sp_lstchg), /* 2 - not a char ptr */
- offsetof(struct spwd, sp_min), /* 3 - not a char ptr */
- offsetof(struct spwd, sp_max), /* 4 - not a char ptr */
- offsetof(struct spwd, sp_warn), /* 5 - not a char ptr */
- offsetof(struct spwd, sp_inact), /* 6 - not a char ptr */
- offsetof(struct spwd, sp_expire) /* 7 - not a char ptr */
-};
-
-int putspent(const struct spwd *p, FILE *stream)
-{
- const char *fmt;
- long x;
- int i;
- int rv = -1;
-
- /* Unlike putpwent and putgrent, glibc does not check the args. */
- if (fprintf(stream, "%s:%s:", p->sp_namp,
- (p->sp_pwdp ? p->sp_pwdp : "")) < 0
- ) {
- goto DO_UNLOCK;
- }
-
- for (i = 0; i < sizeof(put_sp_off); i++) {
- fmt = "%ld:";
- x = *(long *)((char *)p + put_sp_off[i]);
- if (x == -1) {
- fmt += 3;
- }
- if (fprintf(stream, fmt, x) < 0) {
- goto DO_UNLOCK;
- }
- }
-
- if ((p->sp_flag != ~0UL) && (fprintf(stream, "%lu", p->sp_flag) < 0)) {
- goto DO_UNLOCK;
- }
-
- if (fputc('\n', stream) > 0) {
- rv = 0;
- }
-
- DO_UNLOCK:
- return rv;
-}
-#endif
-#endif /* USE_BB_SHADOW */
-
-/**********************************************************************/
-/* Internal functions */
-/**********************************************************************/
-
-static const unsigned char pw_off[] ALIGN1 = {
- offsetof(struct passwd, pw_name), /* 0 */
- offsetof(struct passwd, pw_passwd), /* 1 */
- offsetof(struct passwd, pw_uid), /* 2 - not a char ptr */
- offsetof(struct passwd, pw_gid), /* 3 - not a char ptr */
- offsetof(struct passwd, pw_gecos), /* 4 */
- offsetof(struct passwd, pw_dir), /* 5 */
- offsetof(struct passwd, pw_shell) /* 6 */
-};
-
-static int FAST_FUNC bb__parsepwent(void *data, char *line)
-{
- char *endptr;
- char *p;
- int i;
-
- i = 0;
- while (1) {
- p = (char *) data + pw_off[i];
-
- if (i < 2 || i > 3) {
- *((char **) p) = line;
- if (i == 6) {
- return 0;
- }
- /* NOTE: glibc difference - glibc allows omission of
- * ':' seperators after the gid field if all remaining
- * entries are empty. We require all separators. */
- line = strchr(line, ':');
- if (!line) {
- break;
- }
- } else {
- unsigned long t = strtoul(line, &endptr, 10);
- /* Make sure we had at least one digit, and that the
- * failing char is the next field seperator ':'. See
- * glibc difference note above. */
- /* TODO: Also check for leading whitespace? */
- if ((endptr == line) || (*endptr != ':')) {
- break;
- }
- line = endptr;
- if (i & 1) { /* i == 3 -- gid */
- *((gid_t *) p) = t;
- } else { /* i == 2 -- uid */
- *((uid_t *) p) = t;
- }
- }
-
- *line++ = '\0';
- i++;
- } /* while (1) */
-
- return -1;
-}
-
-/**********************************************************************/
-
-static const unsigned char gr_off[] ALIGN1 = {
- offsetof(struct group, gr_name), /* 0 */
- offsetof(struct group, gr_passwd), /* 1 */
- offsetof(struct group, gr_gid) /* 2 - not a char ptr */
-};
-
-static int FAST_FUNC bb__parsegrent(void *data, char *line)
-{
- char *endptr;
- char *p;
- int i;
- char **members;
- char *end_of_buf;
-
- end_of_buf = ((struct group *) data)->gr_name; /* Evil hack! */
- i = 0;
- while (1) {
- p = (char *) data + gr_off[i];
-
- if (i < 2) {
- *((char **) p) = line;
- line = strchr(line, ':');
- if (!line) {
- break;
- }
- *line++ = '\0';
- i++;
- } else {
- *((gid_t *) p) = strtoul(line, &endptr, 10);
-
- /* NOTE: glibc difference - glibc allows omission of the
- * trailing colon when there is no member list. We treat
- * this as an error. */
-
- /* Make sure we had at least one digit, and that the
- * failing char is the next field seperator ':'. See
- * glibc difference note above. */
- if ((endptr == line) || (*endptr != ':')) {
- break;
- }
-
- i = 1; /* Count terminating NULL ptr. */
- p = endptr;
-
- if (p[1]) { /* We have a member list to process. */
- /* Overwrite the last ':' with a ',' before counting.
- * This allows us to (1) test for initial ','
- * and (2) adds one ',' so that the number of commas
- * equals the member count. */
- *p = ',';
- do {
- /* NOTE: glibc difference - glibc allows and trims leading
- * (but not trailing) space. We treat this as an error. */
- /* NOTE: glibc difference - glibc allows consecutive and
- * trailing commas, and ignores "empty string" users. We
- * treat this as an error. */
- if (*p == ',') {
- ++i;
- *p = 0; /* nul-terminate each member string. */
- if (!*++p || (*p == ',') || isspace(*p)) {
- goto ERR;
- }
- }
- } while (*++p);
- }
-
- /* Now align (p+1), rounding up. */
- /* Assumes sizeof(char **) is a power of 2. */
- members = (char **)( (((intptr_t) p) + sizeof(char **))
- & ~((intptr_t)(sizeof(char **) - 1)) );
-
- if (((char *)(members + i)) > end_of_buf) { /* No space. */
- break;
- }
-
- ((struct group *) data)->gr_mem = members;
-
- if (--i) {
- p = endptr; /* Pointing to char prior to first member. */
- while (1) {
- *members++ = ++p;
- if (!--i)
- break;
- while (*++p)
- continue;
- }
- }
- *members = NULL;
-
- return 0;
- }
- } /* while (1) */
-
- ERR:
- return -1;
-}
-
-/**********************************************************************/
-
-#if ENABLE_USE_BB_SHADOW
-static const unsigned char sp_off[] ALIGN1 = {
- offsetof(struct spwd, sp_namp), /* 0: char* */
- offsetof(struct spwd, sp_pwdp), /* 1: char* */
- offsetof(struct spwd, sp_lstchg), /* 2: long */
- offsetof(struct spwd, sp_min), /* 3: long */
- offsetof(struct spwd, sp_max), /* 4: long */
- offsetof(struct spwd, sp_warn), /* 5: long */
- offsetof(struct spwd, sp_inact), /* 6: long */
- offsetof(struct spwd, sp_expire), /* 7: long */
- offsetof(struct spwd, sp_flag) /* 8: unsigned long */
-};
-
-static int FAST_FUNC bb__parsespent(void *data, char *line)
-{
- char *endptr;
- char *p;
- int i;
-
- i = 0;
- while (1) {
- p = (char *) data + sp_off[i];
- if (i < 2) {
- *((char **) p) = line;
- line = strchr(line, ':');
- if (!line) {
- break; /* error */
- }
- } else {
- *((long *) p) = strtoul(line, &endptr, 10);
- if (endptr == line) {
- *((long *) p) = -1L;
- }
- line = endptr;
- if (i == 8) {
- if (*line != '\0') {
- break; /* error */
- }
- return 0; /* all ok */
- }
- if (*line != ':') {
- break; /* error */
- }
- }
- *line++ = '\0';
- i++;
- }
-
- return EINVAL;
-}
-#endif
-
-/**********************************************************************/
-
-/* Reads until EOF, or until it finds a line which fits in the buffer
- * and for which the parser function succeeds.
- *
- * Returns 0 on success and ENOENT for end-of-file (glibc convention).
- */
-static int bb__pgsreader(
- int FAST_FUNC (*parserfunc)(void *d, char *line),
- void *data,
- char *__restrict line_buff,
- size_t buflen,
- FILE *f)
-{
- int skip;
- int rv = ERANGE;
-
- if (buflen < PWD_BUFFER_SIZE) {
- errno = rv;
- return rv;
- }
-
- skip = 0;
- while (1) {
- if (!fgets(line_buff, buflen, f)) {
- if (feof(f)) {
- rv = ENOENT;
- }
- break;
- }
-
- {
- int line_len = strlen(line_buff) - 1;
- if (line_len >= 0 && line_buff[line_len] == '\n') {
- line_buff[line_len] = '\0';
- } else
- if (line_len + 2 == buflen) {
- /* A start (or continuation) of overlong line */
- skip = 1;
- continue;
- } /* else: a last line in the file, and it has no '\n' */
- }
-
- if (skip) {
- /* This "line" is a remainder of overlong line, ignore */
- skip = 0;
- continue;
- }
-
- /* NOTE: glibc difference - glibc strips leading whitespace from
- * records. We do not allow leading whitespace. */
-
- /* Skip empty lines, comment lines, and lines with leading
- * whitespace. */
- if (line_buff[0] != '\0' && line_buff[0] != '#' && !isspace(line_buff[0])) {
- if (parserfunc == bb__parsegrent) {
- /* Do evil group hack:
- * The group entry parsing function needs to know where
- * the end of the buffer is so that it can construct the
- * group member ptr table. */
- ((struct group *) data)->gr_name = line_buff + buflen;
- }
- if (parserfunc(data, line_buff) == 0) {
- rv = 0;
- break;
- }
- }
- } /* while (1) */
-
- return rv;
-}
["pwd_grp.c" (text/x-csrc)]
/* vi: set sw=4 ts=4: */
/* Copyright (C) 2003 Manuel Novoa III
*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
/* Nov 6, 2003 Initial version.
*
* NOTE: This implementation is quite strict about requiring all
* field seperators. It also does not allow leading whitespace
* except when processing the numeric fields. glibc is more
* lenient. See the various glibc difference comments below.
*
* TODO:
* Move to dynamic allocation of (currently statically allocated)
* buffers; especially for the group-related functions since
* large group member lists will cause error returns.
*/
/* Copyright (C) 2014 Tito Ragusa <farmatito@tiscali.it>
*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
/* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY!!
*
* Rewrite of some parts. Main differences are:
*
* 1) the buffer for getpwuid, getgrgid, getpwnam, getgrnam is dynamically
* allocated and reused by later calls. if ERANGE error pops up it is
* reallocated to the size of the longest line found so far in the
* passwd/group files and reused for later calls.
* If ENABLE_FEATURE_CLEAN_UP is set the buffers are freed at program
* exit using the atexit function to make valgrind happy.
* 2) the passwd/group files:
* a) must contain the expected number of fields (as per count of field
* delimeters ":") or we will complain with a error message.
* b) leading or trailing whitespace in fields is allowed and handled.
* c) some fields are not allowed to be empty (e.g. username, uid/gid,
* homedir, shell) and in this case NULL is returned and errno is
* set to EINVAL. This behaviour could be easily changed by
* modifying PW_DEF, GR_DEF, SP_DEF strings (uppercase
* makes a field mandatory).
* d) the string representing uid/gid must be convertible by strtoXX
* functions or NULL is returned and errno is set to EINVAL.
* e) leading or trailing whitespaces in member names and empty members
* are allowed and handled.
* 3) the internal function for getgrouplist uses a dynamically allocated
* buffer and retries with a bigger one in case it is to small;
* 4) the _r functions use the user supplied buffers that are never reallocated
* but use mostly the same common code as the other functions.
* 5) at the moment only the functions really used by busybox code are
* implemented, if you need a particular missing function it should be
* easy to write it by using the internal common code.
*/
#include "libbb.h"
/* S = string not empty, s = string maybe empty, */
/* I = uid,gid, l = long maybe empty, m = members,*/
/* r = reserved */
#define PW_DEF "SsIIsSS"
static const char *pw_def = PW_DEF;
#define _PW_FIELDS sizeof(PW_DEF)-1
#define GR_DEF "SsIm"
static const char *gr_def = GR_DEF;
#define _GR_FIELDS sizeof(GR_DEF)-1
#if ENABLE_USE_BB_SHADOW
#define SP_DEF "Ssllllllr"
static const char *sp_def = SP_DEF;
#define _SP_FIELDS sizeof(SP_DEF)-1
#endif
/* Initial buffer size */
#define PWD_GRP_BUFSIZE 256
/* for getpw_common_malloc */
static char *pwd_buffer = NULL;
static size_t pwd_buffer_size = PWD_GRP_BUFSIZE;
struct passwd *my_pw;
struct passwd my_pwd;
/* for getgr_common_malloc */
static char *grp_buffer = NULL;
static size_t grp_buffer_size = PWD_GRP_BUFSIZE;
struct group *my_gr;
struct group my_grp;
/* for setpwent, getpwent_r, endpwent */
static FILE *pwf = NULL;
/* for setgrent, getgrent_r, endgrent */
static FILE *grf = NULL;
/* We do no file locking */
#define LOCK ((void) 0)
#define UNLOCK ((void) 0)
/**********************************************************************/
/* Internal functions */
/**********************************************************************/
/* Divide the passwd/group/shadow record in fields
* by substituting the given delimeter
* e.g. ':' or ',' with '\0'.
* Returns the number of fields found.
* Strips leading or trailing whitespace in fields.
*/
static int FAST_FUNC tokenize(char *buffer, int ch)
{
char *p = buffer;
char *s = p;
int num_fields = 1;
while (*p) {
while (isspace(*s)) {
memmove(s, s + 1, strlen(s + 1) + 1);
}
if (*p == ch) {
while (p != s && isspace(*(p - 1))) {
memmove(p - 1, p, strlen(p) + 1);
p = p - 1;
}
*p = '\0';
num_fields++;
s = p + 1;
}
p++;
}
return num_fields;
}
/* Fill the buffer linebuf up to len with
* a line of a passwd/group file.
* Returns 0 on success, ENOENT on EOF and
* ERANGE if buffer is not big enough,
* in the latter case the size needed
* is set in size_t *len.
*/
static int FAST_FUNC get_record_line(FILE *file, char *linebuf, size_t *len)
{
int ch;
int idx = 0;
while ((ch = getc(file)) != EOF) {
if (idx < *len) {
linebuf[idx] = (char) ch;
}
idx++;
if (ch == '\n' || ch == '\0')
break;
}
if (idx > *len) {
*len = idx;
return ERANGE;
}
/* return ENOENT only on EOF and no data */
if (idx > 0) {
/* terminate string and remove trailing '\n' if any.*/
linebuf[idx - 1] = '\0';
return 0;
}
return ENOENT;
}
/* Returns 0 on success and matching line broken up in fields by '\0' in buf or
* error. We require the expected number of fields to be found.
* size_t *len is used to check that the buffer provided is big enough, if not
* we reuse size_t *len to pass the needed length to the caller.
*/
static int FAST_FUNC parse_common(FILE *f, const char *key, int field_pos,
char *buf, size_t *len, const char *filename, int n_fields)
{
int count = 0;
int error;
const char *s;
while ((error = get_record_line(f, buf, len)) == 0) {
count++;
/* Skip empty lines, comment lines */
if (buf[0] != '\0' && buf[0] != '#') {
if (tokenize(buf, ':') == n_fields) {
if (field_pos >= 0) {
if (*(s = nth_string(buf, field_pos))) {
if (key && *key) {
if (strcmp(key, s) == 0) {
/* record found */
break;
}
} /* else skip: caller passed bad key */
} /* else skip: field is empty */
} /*else skip: the field we look for doesn't exist */
if (field_pos < 0) {
/* No field specified: sequential read, return a record */
break;
}
} else {
/* number of fields is wrong */
bb_error_msg("%s: bad record at line %d", filename, count);
}
}
}
return error;
}
static int FAST_FUNC parse_file(const char *filename, int n_fields,
const char *key, int field_pos, char *buf, size_t *len)
{
FILE *f = fopen_for_read(filename);
int ret = errno;
if (f) {
ret = parse_common(f, key, field_pos, buf, len, filename, n_fields);
fclose(f);
}
return ret;
}
/* Convert passwd/group/shadow file record in buffer to a struct */
static void * FAST_FUNC convert_to_struct(const char *def,
const unsigned char *off, char *buffer,
void *result, int *error)
{
int idx;
long ret;
char *m;
char **members = NULL;
for (idx = 0; def[idx] != '\0'; idx++) {
if (def[idx] == 'S' || def[idx] == 's') {
m = (char *) nth_string(buffer, idx);
*(char **)((char *)result + off[idx]) = m;
if (!*m && (def[idx] == 'S')) {
*error = EINVAL;
}
}
if (def[idx] == 'I') {
m = (char *) nth_string(buffer, idx);
*(int *)((int) result + off[idx]) = bb_strtou(m, NULL, 10);
if (errno) {
*error = EINVAL;
}
}
#if ENABLE_USE_BB_SHADOW
if (def[idx] == 'l') {
char *endptr;
m = (char *) nth_string(buffer, idx);
ret = bb_strtol(m, &endptr, 10);
if (endptr == m) {
ret = -1L;
} else if (errno) {
*error = EINVAL;
}
*(long *)((long) result + off[idx]) = ret;
}
#endif
if (def[idx] == 'm') {
char *s = (char *) nth_string(buffer, idx);
int i = tokenize(s, ',');
char *p = (char *) nth_string(s, i);
/* Now align (p+1), rounding up. */
/* Assumes sizeof(char **) is a power of 2. */
members = (char **)((((intptr_t) p) + sizeof(char **))
& ~((intptr_t)(sizeof(char **) - 1)));
((struct group *) result)->gr_mem = members;
/* Pointing to char prior to first member. */
p = s - 1;
while (1) {
if (*(p + 1))
*members++ = ++p;
if (!--i)
break;
while (*++p)
continue;
}
*members = NULL;
}
}
if (*error) {
result = NULL;
errno = *error;
}
return result;
}
#if ENABLE_USE_BB_SHADOW
static const unsigned char sp_off[] ALIGN1 = {
offsetof(struct spwd, sp_namp), /* 1 - Login name */
offsetof(struct spwd, sp_pwdp), /* 2 - Encrypted password */
offsetof(struct spwd, sp_lstchg), /* 2 - not a char ptr */
offsetof(struct spwd, sp_min), /* 3 - not a char ptr */
offsetof(struct spwd, sp_max), /* 4 - not a char ptr */
offsetof(struct spwd, sp_warn), /* 5 - not a char ptr */
offsetof(struct spwd, sp_inact), /* 6 - not a char ptr */
offsetof(struct spwd, sp_expire) /* 7 - not a char ptr */
// ,offsetof(struct spwd, sp_flag) /* 8 - Reserved */
};
int getspnam_r(const char *name, struct spwd *spbuf, char *buf, size_t buflen,
struct spwd **spbufp)
{
int error;
size_t len = buflen;
*spbufp = NULL;
error = parse_file(_PATH_SHADOW, _SP_FIELDS, name, 0, buf, &len);
if (error == 0) {
*spbufp = convert_to_struct(sp_def, sp_off, buf, spbuf, &error);
}
return error;
}
#endif /* ENABLE_USE_BB_SHADOW */
static const unsigned char pw_off[] ALIGN1 = {
offsetof(struct passwd, pw_name), /* 0 */
offsetof(struct passwd, pw_passwd), /* 1 */
offsetof(struct passwd, pw_uid), /* 2 - not a char ptr */
offsetof(struct passwd, pw_gid), /* 3 - not a char ptr */
offsetof(struct passwd, pw_gecos), /* 4 */
offsetof(struct passwd, pw_dir), /* 5 */
offsetof(struct passwd, pw_shell) /* 6 */
};
static const unsigned char gr_off[] ALIGN1 = {
offsetof(struct group, gr_name), /* 0 */
offsetof(struct group, gr_passwd), /* 1 */
offsetof(struct group, gr_gid), /* 2 - not a char ptr */
offsetof(struct group, gr_mem) /* 3 - char ** ptr */
};
/* Common code for getpwxxx/_r functions. */
static int FAST_FUNC getpw_common(const char *name, int field,
struct passwd *pwd, char *buf, size_t *buflen,
struct passwd **result)
{
int error;
*result = NULL;
error = parse_file(_PATH_PASSWD, _PW_FIELDS, name, field, buf, buflen);
if (error == 0) {
*result = convert_to_struct(pw_def, pw_off, buf, pwd, &error);
}
return (error == ENOENT) ? 0 : error;
}
/* Common code for getgrxxx/_r functions. */
static int FAST_FUNC getgr_common(const char *name, int field,
struct group *grp, char *buf, size_t *buflen,
struct group **result)
{
int error;
*result = NULL;
error = parse_file(_PATH_GROUP, _GR_FIELDS, name, field, buf, buflen);
if (error == 0) {
*result = convert_to_struct(gr_def, gr_off, buf, grp, &error);
}
return (error == ENOENT) ? 0 : error;
}
#if ENABLE_FEATURE_CLEAN_UP
static void FAST_FUNC free_pwd(void)
{
free(pwd_buffer);
}
#endif
/* Common code for getpwxxx functions. */
static struct passwd * FAST_FUNC getpw_common_malloc(const char *name, int field)
{
int error = 0;
#if ENABLE_FEATURE_CLEAN_UP
if (pwd_buffer == NULL) {
atexit(free_pwd);
}
#endif
retry:
pwd_buffer = xrealloc(pwd_buffer, pwd_buffer_size * sizeof(char));
error = getpw_common(name, field, &my_pwd, pwd_buffer, &pwd_buffer_size, &my_pw);
if (error == ERANGE) {
errno = 0;
goto retry;
}
return my_pw;
}
#if ENABLE_FEATURE_CLEAN_UP
static void FAST_FUNC free_grp(void)
{
free(grp_buffer);
}
#endif
/* Common code for getgrxxx functions. */
static struct group * FAST_FUNC getgr_common_malloc(const char *name, int field)
{
int error = 0;
#if ENABLE_FEATURE_CLEAN_UP
if (grp_buffer == NULL) {
atexit(free_grp);
}
#endif
retry:
grp_buffer = xrealloc(grp_buffer, grp_buffer_size * sizeof(char));
error = getgr_common(name, field, &my_grp, grp_buffer, &grp_buffer_size, &my_gr);
if (error == ERANGE) {
errno = 0;
goto retry;
}
return my_gr;
}
/**********************************************************************/
int getpwent_r(struct passwd *pwbuf, char *buf, size_t buflen, struct passwd **pwbufp)
{
int error;
size_t len = buflen;
LOCK;
*pwbufp = NULL;
if (!pwf) {
pwf = fopen_for_read(_PATH_PASSWD);
if (!pwf) {
return errno;
}
close_on_exec_on(fileno(pwf));
}
error = parse_common(pwf, NULL, -1, buf, &len, _PATH_PASSWD, _PW_FIELDS);
if (error == 0) {
*pwbufp = convert_to_struct(pw_def, pw_off, buf, pwbuf, &error);
}
UNLOCK;
return error;
}
int getgrent_r(struct group *gbuf, char *buf, size_t buflen, struct group **gbufp)
{
int error;
size_t len = buflen;
LOCK;
*gbufp = NULL;
if (!grf) {
grf = fopen_for_read(_PATH_GROUP);
if (!grf) {
return errno;
}
close_on_exec_on(fileno(grf));
}
error = parse_common(grf, NULL, -1, buf, &len, _PATH_GROUP, _GR_FIELDS);
if (error == 0) {
*gbufp = convert_to_struct(gr_def, gr_off, buf, gbuf, &error);
}
UNLOCK;
return error;
}
int getpwnam_r(const char *name, struct passwd *pwd, char *buf, size_t buflen,
struct passwd **result)
{
size_t len = buflen;
return getpw_common(name, 0, pwd, buf, &len, result);
}
int getgrnam_r(const char *name, struct group *grp, char *buf, size_t buflen,
struct group **result)
{
size_t len = buflen;
return getgr_common(name, 0, grp, buf, &len, result);
}
int getpwuid_r(uid_t uid, struct passwd *pwd, char *buf, size_t buflen,
struct passwd **result)
{
size_t len = buflen;
return getpw_common(utoa(uid), 2, pwd, buf, &len, result);
}
int getgrgid_r(gid_t gid, struct group *grp, char *buf, size_t buflen,
struct group **result)
{
size_t len = buflen;
return getgr_common(utoa(gid), 2, grp, buf, &len, result);
}
struct passwd *getpwnam(const char *name)
{
return getpw_common_malloc(name, 0);
}
struct group *getgrnam(const char *name)
{
return getgr_common_malloc(name, 0);
}
struct passwd *getpwuid(uid_t uid)
{
return getpw_common_malloc(utoa(uid), 2);
}
struct group *getgrgid(gid_t gid)
{
return getgr_common_malloc(utoa(gid), 2);
}
void endpwent(void)
{
LOCK;
if (pwf) {
fclose(pwf);
pwf = NULL;
}
UNLOCK;
}
void setpwent(void)
{
LOCK;
if (pwf) {
rewind(pwf);
}
UNLOCK;
}
void endgrent(void)
{
LOCK;
if (grf) {
fclose(grf);
grf = NULL;
}
UNLOCK;
}
void setgrent(void)
{
LOCK;
if (grf) {
rewind(grf);
}
UNLOCK;
}
static gid_t * FAST_FUNC getgrouplist_internal(int *ngroups_ptr,
const char *user, gid_t gid)
{
FILE *f;
struct group *gr;
struct group grp;
gid_t *group_list;
int ngroups;
char * buffer = NULL;
size_t buflen = PWD_GRP_BUFSIZE;
int ret = 0;
retry:
group_list = NULL;
ngroups = 1;
f = fopen_for_read(_PATH_GROUP);
if (f) {
group_list = xrealloc(group_list, 1 * sizeof(gid_t));
*group_list = gid;
buffer = xrealloc(buffer, buflen * sizeof( char));
while ((ret = parse_common(f, NULL, -1, buffer, &buflen,
_PATH_GROUP, _GR_FIELDS)) == 0) {
gr = convert_to_struct(gr_def, gr_off, buffer, &grp, &ret);
if (gr != NULL) {
if (gr->gr_gid != gid) {
/* reuse int ret */
for (/*ret = 0*/; gr->gr_mem[ret] != NULL; ret++) {
if (strcmp(gr->gr_mem[ret], user) == 0) {
group_list = xrealloc(group_list,
(ngroups + 1) * sizeof(gid_t));
group_list[ngroups++] = gr->gr_gid;
}
}
}
}
}
fclose(f);
}
if (ret == ERANGE) {
/* buffer was to small, retry */
free(group_list);
goto retry;
}
free(buffer);
*ngroups_ptr = ngroups;
return group_list;
}
int initgroups(const char *user, gid_t gid)
{
int ngroups;
gid_t *group_list = getgrouplist_internal(&ngroups, user, gid);
ngroups = setgroups(ngroups, group_list);
free(group_list);
return ngroups;
}
int getgrouplist(const char *user, gid_t gid, gid_t *groups, int *ngroups)
{
int ngroups_old = *ngroups;
gid_t *group_list = getgrouplist_internal(ngroups, user, gid);
if (*ngroups <= ngroups_old) {
ngroups_old = *ngroups;
memcpy(groups, group_list, ngroups_old * sizeof(groups[0]));
} else {
ngroups_old = -1;
}
free(group_list);
return ngroups_old;
}
_______________________________________________
busybox mailing list
busybox@busybox.net
http://lists.busybox.net/mailman/listinfo/busybox
[prev in list] [next in list] [prev in thread] [next in thread]
Configure |
About |
News |
Add a list |
Sponsored by KoreLogic