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-rw-r--r--lib/shadow.c530
1 files changed, 530 insertions, 0 deletions
diff --git a/lib/shadow.c b/lib/shadow.c
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index 0000000..b628b65
--- /dev/null
+++ b/lib/shadow.c
@@ -0,0 +1,530 @@
+/*
+ * SPDX-FileCopyrightText: 1989 - 1994, Julianne Frances Haugh
+ * SPDX-FileCopyrightText: 1996 - 1998, Marek Michałkiewicz
+ * SPDX-FileCopyrightText: 2003 - 2005, Tomasz Kłoczko
+ * SPDX-FileCopyrightText: 2009 , Nicolas François
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <config.h>
+
+/* Newer versions of Linux libc already have shadow support. */
+#ifndef HAVE_GETSPNAM
+
+#ident "$Id$"
+
+#include <sys/types.h>
+#include "prototypes.h"
+#include "defines.h"
+#include <stdio.h>
+#ifdef USE_NIS
+static bool nis_used;
+static bool nis_ignore;
+static enum { native, start, middle, native2 } nis_state;
+static bool nis_bound;
+static char *nis_domain;
+static char *nis_key;
+static int nis_keylen;
+static char *nis_val;
+static int nis_vallen;
+
+#define IS_NISCHAR(c) ((c)=='+')
+#endif
+
+static FILE *shadow;
+
+#define FIELDS 9
+#define OFIELDS 5
+
+#ifdef USE_NIS
+
+/*
+ * __setspNIS - turn on or off NIS searches
+ */
+
+void __setspNIS (bool flag)
+{
+ nis_ignore = !flag;
+
+ if (nis_ignore) {
+ nis_used = false;
+ }
+}
+
+/*
+ * bind_nis - bind to NIS server
+ */
+
+static int bind_nis (void)
+{
+ if (yp_get_default_domain (&nis_domain)) {
+ return -1;
+ }
+
+ nis_bound = true;
+ return 0;
+}
+#endif
+
+/*
+ * setspent - initialize access to shadow text and DBM files
+ */
+
+void setspent (void)
+{
+ if (NULL != shadow) {
+ rewind (shadow);
+ }else {
+ shadow = fopen (SHADOW_FILE, "r");
+ }
+
+#ifdef USE_NIS
+ nis_state = native;
+#endif
+}
+
+/*
+ * endspent - terminate access to shadow text and DBM files
+ */
+
+void endspent (void)
+{
+ if (NULL != shadow) {
+ (void) fclose (shadow);
+ }
+
+ shadow = (FILE *) 0;
+}
+
+/*
+ * my_sgetspent - convert string in shadow file format to (struct spwd *)
+ */
+
+static struct spwd *my_sgetspent (const char *string)
+{
+ static char spwbuf[BUFSIZ];
+ static struct spwd spwd;
+ char *fields[FIELDS];
+ char *cp;
+ int i;
+
+ /*
+ * Copy string to local buffer. It has to be tokenized and we
+ * have to do that to our private copy.
+ */
+
+ if (strlen (string) >= sizeof spwbuf)
+ return 0;
+ strcpy (spwbuf, string);
+
+ cp = strrchr (spwbuf, '\n');
+ if (NULL != cp)
+ *cp = '\0';
+
+ /*
+ * Tokenize the string into colon separated fields. Allow up to
+ * FIELDS different fields.
+ */
+
+ for (cp = spwbuf, i = 0; *cp && i < FIELDS; i++) {
+ fields[i] = cp;
+ while (*cp && *cp != ':')
+ cp++;
+
+ if (*cp)
+ *cp++ = '\0';
+ }
+
+ if (i == (FIELDS - 1))
+ fields[i++] = cp;
+
+ if ((cp && *cp) || (i != FIELDS && i != OFIELDS))
+ return 0;
+
+ /*
+ * Start populating the structure. The fields are all in
+ * static storage, as is the structure we pass back. If we
+ * ever see a name with '+' as the first character, we try
+ * to turn on NIS processing.
+ */
+
+ spwd.sp_namp = fields[0];
+#ifdef USE_NIS
+ if (IS_NISCHAR (fields[0][0])) {
+ nis_used = true;
+ }
+#endif
+ spwd.sp_pwdp = fields[1];
+
+ /*
+ * Get the last changed date. For all of the integer fields,
+ * we check for proper format. It is an error to have an
+ * incorrectly formatted number, unless we are using NIS.
+ */
+
+ if (fields[2][0] == '\0') {
+ spwd.sp_lstchg = -1;
+ } else {
+ if (getlong (fields[2], &spwd.sp_lstchg) == 0) {
+#ifdef USE_NIS
+ if (nis_used) {
+ spwd.sp_lstchg = -1;
+ } else
+#endif
+ return 0;
+ } else if (spwd.sp_lstchg < 0) {
+ return 0;
+ }
+ }
+
+ /*
+ * Get the minimum period between password changes.
+ */
+
+ if (fields[3][0] == '\0') {
+ spwd.sp_min = -1;
+ } else {
+ if (getlong (fields[3], &spwd.sp_min) == 0) {
+#ifdef USE_NIS
+ if (nis_used) {
+ spwd.sp_min = -1;
+ } else
+#endif
+ {
+ return 0;
+ }
+ } else if (spwd.sp_min < 0) {
+ return 0;
+ }
+ }
+
+ /*
+ * Get the maximum number of days a password is valid.
+ */
+
+ if (fields[4][0] == '\0') {
+ spwd.sp_max = -1;
+ } else {
+ if (getlong (fields[4], &spwd.sp_max) == 0) {
+#ifdef USE_NIS
+ if (nis_used) {
+ spwd.sp_max = -1;
+ } else
+#endif
+ return 0;
+ } else if (spwd.sp_max < 0) {
+ return 0;
+ }
+ }
+
+ /*
+ * If there are only OFIELDS fields (this is a SVR3.2 /etc/shadow
+ * formatted file), initialize the other field members to -1.
+ */
+
+ if (i == OFIELDS) {
+ spwd.sp_warn = -1;
+ spwd.sp_inact = -1;
+ spwd.sp_expire = -1;
+ spwd.sp_flag = SHADOW_SP_FLAG_UNSET;
+
+ return &spwd;
+ }
+
+ /*
+ * Get the number of days of password expiry warning.
+ */
+
+ if (fields[5][0] == '\0') {
+ spwd.sp_warn = -1;
+ } else {
+ if (getlong (fields[5], &spwd.sp_warn) == 0) {
+#ifdef USE_NIS
+ if (nis_used) {
+ spwd.sp_warn = -1;
+ } else
+#endif
+ {
+ return 0;
+ }
+ } else if (spwd.sp_warn < 0) {
+ return 0;
+ }
+ }
+
+ /*
+ * Get the number of days of inactivity before an account is
+ * disabled.
+ */
+
+ if (fields[6][0] == '\0') {
+ spwd.sp_inact = -1;
+ } else {
+ if (getlong (fields[6], &spwd.sp_inact) == 0) {
+#ifdef USE_NIS
+ if (nis_used) {
+ spwd.sp_inact = -1;
+ } else
+#endif
+ {
+ return 0;
+ }
+ } else if (spwd.sp_inact < 0) {
+ return 0;
+ }
+ }
+
+ /*
+ * Get the number of days after the epoch before the account is
+ * set to expire.
+ */
+
+ if (fields[7][0] == '\0') {
+ spwd.sp_expire = -1;
+ } else {
+ if (getlong (fields[7], &spwd.sp_expire) == 0) {
+#ifdef USE_NIS
+ if (nis_used) {
+ spwd.sp_expire = -1;
+ } else
+#endif
+ {
+ return 0;
+ }
+ } else if (spwd.sp_expire < 0) {
+ return 0;
+ }
+ }
+
+ /*
+ * This field is reserved for future use. But it isn't supposed
+ * to have anything other than a valid integer in it.
+ */
+
+ if (fields[8][0] == '\0') {
+ spwd.sp_flag = SHADOW_SP_FLAG_UNSET;
+ } else {
+ if (getulong (fields[8], &spwd.sp_flag) == 0) {
+#ifdef USE_NIS
+ if (nis_used) {
+ spwd.sp_flag = SHADOW_SP_FLAG_UNSET;
+ } else
+#endif
+ {
+ return 0;
+ }
+ } else if (spwd.sp_flag < 0) {
+ return 0;
+ }
+ }
+
+ return (&spwd);
+}
+
+/*
+ * fgetspent - get an entry from a /etc/shadow formatted stream
+ */
+
+struct spwd *fgetspent (FILE * fp)
+{
+ char buf[BUFSIZ];
+ char *cp;
+
+ if (NULL == fp) {
+ return (0);
+ }
+
+#ifdef USE_NIS
+ while (fgets (buf, (int) sizeof buf, fp) != (char *) 0)
+#else
+ if (fgets (buf, (int) sizeof buf, fp) != (char *) 0)
+#endif
+ {
+ cp = strchr (buf, '\n');
+ if (NULL != cp) {
+ *cp = '\0';
+ }
+#ifdef USE_NIS
+ if (nis_ignore && IS_NISCHAR (buf[0])) {
+ continue;
+ }
+#endif
+ return my_sgetspent (buf);
+ }
+ return 0;
+}
+
+/*
+ * getspent - get a (struct spwd *) from the current shadow file
+ */
+
+struct spwd *getspent (void)
+{
+#ifdef USE_NIS
+ int nis_1_user = 0;
+ struct spwd *val;
+#endif
+ if (NULL == shadow) {
+ setspent ();
+ }
+
+#ifdef USE_NIS
+ again:
+ /*
+ * See if we are reading from the local file.
+ */
+
+ if (nis_state == native || nis_state == native2) {
+
+ /*
+ * Get the next entry from the shadow file. Return NULL
+ * right away if there is none.
+ */
+
+ val = fgetspent (shadow);
+ if (NULL == val)
+ return 0;
+
+ /*
+ * If this entry began with a NIS escape character, we have
+ * to see if this is just a single user, or if the entire
+ * map is being asked for.
+ */
+
+ if (IS_NISCHAR (val->sp_namp[0])) {
+ if (val->sp_namp[1])
+ nis_1_user = 1;
+ else
+ nis_state = start;
+ }
+
+ /*
+ * If this isn't a NIS user and this isn't an escape to go
+ * use a NIS map, it must be a regular local user.
+ */
+
+ if (nis_1_user == 0 && nis_state != start)
+ return val;
+
+ /*
+ * If this is an escape to use an NIS map, switch over to
+ * that bunch of code.
+ */
+
+ if (nis_state == start)
+ goto again;
+
+ /*
+ * NEEDSWORK. Here we substitute pieces-parts of this entry.
+ */
+
+ return 0;
+ } else {
+ if (!nis_bound) {
+ if (bind_nis ()) {
+ nis_state = native2;
+ goto again;
+ }
+ }
+ if (nis_state == start) {
+ if (yp_first (nis_domain, "shadow.bynam", &nis_key,
+ &nis_keylen, &nis_val, &nis_vallen)) {
+ nis_state = native2;
+ goto again;
+ }
+ nis_state = middle;
+ } else if (nis_state == middle) {
+ if (yp_next (nis_domain, "shadow.bynam", nis_key,
+ nis_keylen, &nis_key, &nis_keylen,
+ &nis_val, &nis_vallen)) {
+ nis_state = native2;
+ goto again;
+ }
+ }
+ return my_sgetspent (nis_val);
+ }
+#else
+ return (fgetspent (shadow));
+#endif
+}
+
+/*
+ * getspnam - get a shadow entry by name
+ */
+
+struct spwd *getspnam (const char *name)
+{
+ struct spwd *sp;
+
+#ifdef USE_NIS
+ static char save_name[16];
+ bool nis_disabled = false;
+#endif
+
+ setspent ();
+
+#ifdef USE_NIS
+ /*
+ * Search the shadow.byname map for this user.
+ */
+
+ if (!nis_ignore && !nis_bound) {
+ bind_nis ();
+ }
+
+ if (!nis_ignore && nis_bound) {
+ char *cp;
+
+ if (yp_match (nis_domain, "shadow.byname", name,
+ strlen (name), &nis_val, &nis_vallen) == 0) {
+
+ cp = strchr (nis_val, '\n');
+ if (NULL != cp) {
+ *cp = '\0';
+ }
+
+ nis_state = middle;
+ sp = my_sgetspent (nis_val);
+ if (NULL != sp) {
+ strcpy (save_name, sp->sp_namp);
+ nis_key = save_name;
+ nis_keylen = strlen (save_name);
+ }
+ endspent ();
+ return sp;
+ } else {
+ nis_state = native2;
+ }
+ }
+#endif
+#ifdef USE_NIS
+ /*
+ * NEEDSWORK -- this is a mess, and it is the same mess in the
+ * other three files. I can't just blindly turn off NIS because
+ * this might be the first pass through the local files. In
+ * that case, I never discover that NIS is present.
+ */
+
+ if (nis_used) {
+ nis_ignore = true;
+ nis_disabled = true;
+ }
+#endif
+ while ((sp = getspent ()) != (struct spwd *) 0) {
+ if (strcmp (name, sp->sp_namp) == 0) {
+ break;
+ }
+ }
+#ifdef USE_NIS
+ if (nis_disabled) {
+ nis_ignore = false;
+ }
+#endif
+ endspent ();
+ return (sp);
+}
+#else
+extern int errno; /* warning: ANSI C forbids an empty source file */
+#endif
+