X-Git-Url: https://git.cameronkatri.com/pw-darwin.git/blobdiff_plain/1b5065c251cfbf3b8a8f40c23b0a71b8365092a4..1191611aa1bf45ab42f08651b0234155c0e6605b:/libutil/pw_util.c

diff --git a/libutil/pw_util.c b/libutil/pw_util.c
index d219917..befd1fb 100644
--- a/libutil/pw_util.c
+++ b/libutil/pw_util.c
@@ -17,10 +17,6 @@
  * 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. All advertising materials mentioning features or use of this software
- *    must display the following acknowledgement:
- *	This product includes software developed by the University of
- *	California, Berkeley and its contributors.
  * 4. 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.
@@ -58,8 +54,8 @@ static const char rcsid[] =
 #include <sys/stat.h>
 #include <sys/wait.h>
 
-#include <err.h>
 #include <ctype.h>
+#include <err.h>
 #include <fcntl.h>
 #include <inttypes.h>
 #include <libgen.h>
@@ -71,7 +67,7 @@ static const char rcsid[] =
 #include <string.h>
 #include <unistd.h>
 
-#include <libutil.h>
+#include "libutil.h"
 
 static pid_t editpid = -1;
 static int lockfd = -1;
@@ -80,6 +76,7 @@ static char passwd_dir[PATH_MAX];
 static char tempname[PATH_MAX];
 static int initialized;
 
+#if 0
 void
 pw_cont(int sig)
 {
@@ -87,6 +84,7 @@ pw_cont(int sig)
 	if (editpid != -1)
 		kill(editpid, sig);
 }
+#endif
 
 /*
  * Initialize statics and set limits, signals & umask to try to avoid
@@ -102,7 +100,7 @@ pw_init(const char *dir, const char *master)
 	if (dir == NULL) {
 		strcpy(passwd_dir, _PATH_ETC);
 	} else {
-		if (strlen(dir) >= sizeof passwd_dir) {
+		if (strlen(dir) >= sizeof(passwd_dir)) {
 			errno = ENAMETOOLONG;
 			return (-1);
 		}
@@ -112,13 +110,13 @@ pw_init(const char *dir, const char *master)
 	if (master == NULL) {
 		if (dir == NULL) {
 			strcpy(masterpasswd, _PATH_MASTERPASSWD);
-		} else if (snprintf(masterpasswd, sizeof masterpasswd, "%s/%s",
-		    passwd_dir, _MASTERPASSWD) > sizeof masterpasswd) {
+		} else if (snprintf(masterpasswd, sizeof(masterpasswd), "%s/%s",
+		    passwd_dir, _MASTERPASSWD) > (int)sizeof(masterpasswd)) {
 			errno = ENAMETOOLONG;
 			return (-1);
 		}
 	} else {
-		if (strlen(master) >= sizeof masterpasswd) {
+		if (strlen(master) >= sizeof(masterpasswd)) {
 			errno = ENAMETOOLONG;
 			return (-1);
 		}
@@ -181,11 +179,8 @@ pw_lock(void)
 	for (;;) {
 		struct stat st;
 
-		lockfd = open(masterpasswd, O_RDONLY, 0);
-		if (lockfd < 0 || fcntl(lockfd, F_SETFD, 1) == -1)
-			err(1, "%s", masterpasswd);
-		/* XXX vulnerable to race conditions */
-		if (flock(lockfd, LOCK_EX|LOCK_NB) == -1) {
+		lockfd = flopen(masterpasswd, O_RDONLY|O_NONBLOCK|O_CLOEXEC, 0);
+		if (lockfd == -1) {
 			if (errno == EWOULDBLOCK) {
 				errx(1, "the password db file is busy");
 			} else {
@@ -216,7 +211,7 @@ int
 pw_tmp(int mfd)
 {
 	char buf[8192];
-	ssize_t nr, nw;
+	ssize_t nr;
 	const char *p;
 	int tfd;
 
@@ -226,16 +221,16 @@ pw_tmp(int mfd)
 		++p;
 	else
 		p = masterpasswd;
-	if (snprintf(tempname, sizeof tempname, "%.*spw.XXXXXX",
-		(int)(p - masterpasswd), masterpasswd) >= sizeof tempname) {
+	if (snprintf(tempname, sizeof(tempname), "%.*spw.XXXXXX",
+		(int)(p - masterpasswd), masterpasswd) >= (int)sizeof(tempname)) {
 		errno = ENAMETOOLONG;
 		return (-1);
 	}
 	if ((tfd = mkstemp(tempname)) == -1)
 		return (-1);
 	if (mfd != -1) {
-		while ((nr = read(mfd, buf, sizeof buf)) > 0)
-			if ((nw = write(tfd, buf, nr)) != nr)
+		while ((nr = read(mfd, buf, sizeof(buf))) > 0)
+			if (write(tfd, buf, (size_t)nr) != nr)
 				break;
 		if (nr != 0) {
 			unlink(tempname);
@@ -264,11 +259,13 @@ pw_mkdb(const char *user)
 		/* child */
 		if (user == NULL)
 			execl(_PATH_PWD_MKDB, "pwd_mkdb", "-p",
-			    "-d", passwd_dir, tempname, NULL);
+			    "-d", passwd_dir, tempname, (char *)NULL);
 		else
 			execl(_PATH_PWD_MKDB, "pwd_mkdb", "-p",
-			    "-d", passwd_dir, "-u", user, tempname, NULL);
+			    "-d", passwd_dir, "-u", user, tempname,
+			    (char *)NULL);
 		_exit(1);
+		/* NOTREACHED */
 	default:
 		/* parent */
 		break;
@@ -288,6 +285,8 @@ pw_mkdb(const char *user)
 int
 pw_edit(int notsetuid)
 {
+	struct sigaction sa, sa_int, sa_quit;
+	sigset_t oldsigset, nsigset;
 	struct stat st1, st2;
 	const char *editor;
 	int pstat;
@@ -296,27 +295,39 @@ pw_edit(int notsetuid)
 		editor = _PATH_VI;
 	if (stat(tempname, &st1) == -1)
 		return (-1);
+	sa.sa_handler = SIG_IGN;
+	sigemptyset(&sa.sa_mask);
+	sa.sa_flags = 0;
+	sigaction(SIGINT, &sa, &sa_int);
+	sigaction(SIGQUIT, &sa, &sa_quit);
+	sigemptyset(&nsigset);
+	sigaddset(&nsigset, SIGCHLD);
+	sigprocmask(SIG_BLOCK, &nsigset, &oldsigset);
 	switch ((editpid = fork())) {
 	case -1:
 		return (-1);
 	case 0:
-		/* child */
+		sigaction(SIGINT, &sa_int, NULL);
+		sigaction(SIGQUIT, &sa_quit, NULL);
+		sigprocmask(SIG_SETMASK, &oldsigset, NULL);
 		if (notsetuid) {
 			(void)setgid(getgid());
 			(void)setuid(getuid());
 		}
 		errno = 0;
-		execlp(editor, basename(editor), tempname, NULL);
+		execlp(editor, basename(editor), tempname, (char *)NULL);
 		_exit(errno);
 	default:
 		/* parent */
 		break;
 	}
 	for (;;) {
-		editpid = waitpid(editpid, &pstat, WUNTRACED);
-		if (editpid == -1) {
+		if (waitpid(editpid, &pstat, WUNTRACED) == -1) {
+			if (errno == EINTR)
+				continue;
 			unlink(tempname);
-			return (-1);
+			editpid = -1;
+			break;
 		} else if (WIFSTOPPED(pstat)) {
 			raise(WSTOPSIG(pstat));
 		} else if (WIFEXITED(pstat) && WEXITSTATUS(pstat) == 0) {
@@ -324,14 +335,17 @@ pw_edit(int notsetuid)
 			break;
 		} else {
 			unlink(tempname);
-			*tempname = '\0';
 			editpid = -1;
-			return (-1);
+			break;
 		}
 	}
+	sigaction(SIGINT, &sa_int, NULL);
+	sigaction(SIGQUIT, &sa_quit, NULL);
+	sigprocmask(SIG_SETMASK, &oldsigset, NULL);
 	if (stat(tempname, &st2) == -1)
 		return (-1);
-	return (st1.st_mtime != st2.st_mtime);
+	return (st1.st_mtim.tv_sec != st2.st_mtim.tv_sec ||
+	    st1.st_mtim.tv_nsec != st2.st_mtim.tv_nsec);
 }
 
 /*
@@ -365,7 +379,7 @@ pw_fini(void)
  * Compares two struct pwds.
  */
 int
-pw_equal(struct passwd *pw1, struct passwd *pw2)
+pw_equal(const struct passwd *pw1, const struct passwd *pw2)
 {
 	return (strcmp(pw1->pw_name, pw2->pw_name) == 0 &&
 	    pw1->pw_uid == pw2->pw_uid &&
@@ -382,7 +396,7 @@ pw_equal(struct passwd *pw1, struct passwd *pw2)
  * Make a passwd line out of a struct passwd.
  */
 char *
-pw_make(struct passwd *pw)
+pw_make(const struct passwd *pw)
 {
 	char *line;
 
@@ -390,23 +404,51 @@ pw_make(struct passwd *pw)
 	    pw->pw_passwd, (uintmax_t)pw->pw_uid, (uintmax_t)pw->pw_gid,
 	    pw->pw_class, (uintmax_t)pw->pw_change, (uintmax_t)pw->pw_expire,
 	    pw->pw_gecos, pw->pw_dir, pw->pw_shell);
-	return line;
+	return (line);
+}
+
+/*
+ * Make a passwd line (in v7 format) out of a struct passwd
+ */
+char *
+pw_make_v7(const struct passwd *pw)
+{
+	char *line;
+
+	asprintf(&line, "%s:*:%ju:%ju:%s:%s:%s", pw->pw_name,
+	    (uintmax_t)pw->pw_uid, (uintmax_t)pw->pw_gid,
+	    pw->pw_gecos, pw->pw_dir, pw->pw_shell);
+	return (line);
 }
 
 /*
- * Copy password file from one descriptor to another, replacing or adding
- * a single record on the way.
+ * Copy password file from one descriptor to another, replacing, deleting
+ * or adding a single record on the way.
  */
 int
-pw_copy(int ffd, int tfd, struct passwd *pw, struct passwd *old_pw)
+pw_copy(int ffd, int tfd, const struct passwd *pw, struct passwd *old_pw)
 {
 	char buf[8192], *end, *line, *p, *q, *r, t;
 	struct passwd *fpw;
-	ssize_t len;
-	int eof;
+	const struct passwd *spw;
+	size_t len;
+	int eof, readlen;
 
-	if ((line = pw_make(pw)) == NULL)
-		return (-1);
+	if (old_pw == NULL && pw == NULL)
+			return (-1);
+
+	spw = old_pw;
+	/* deleting a user */
+	if (pw == NULL) {
+		line = NULL;
+	} else {
+		if ((line = pw_make(pw)) == NULL)
+			return (-1);
+	}
+
+	/* adding a user */
+	if (spw == NULL)
+		spw = pw;
 
 	eof = 0;
 	len = 0;
@@ -421,7 +463,7 @@ pw_copy(int ffd, int tfd, struct passwd *pw, struct passwd *old_pw)
 		if (q >= end) {
 			if (eof)
 				break;
-			if (q - p >= sizeof buf) {
+			if ((size_t)(q - p) >= sizeof(buf)) {
 				warnx("passwd line too long");
 				errno = EINVAL; /* hack */
 				goto err;
@@ -432,14 +474,16 @@ pw_copy(int ffd, int tfd, struct passwd *pw, struct passwd *old_pw)
 			} else {
 				p = q = end = buf;
 			}
-			len = read(ffd, end, sizeof buf - (end - buf));
-			if (len == -1)
+			readlen = read(ffd, end, sizeof(buf) - (end - buf));
+			if (readlen == -1)
 				goto err;
+			else
+				len = (size_t)readlen;
 			if (len == 0 && p == buf)
 				break;
 			end += len;
 			len = end - buf;
-			if (len < sizeof buf) {
+			if (len < (ssize_t)sizeof(buf)) {
 				eof = 1;
 				if (len > 0 && buf[len - 1] != '\n')
 					++len, *end++ = '\n';
@@ -459,51 +503,77 @@ pw_copy(int ffd, int tfd, struct passwd *pw, struct passwd *old_pw)
 		}
 
 		/* is it the one we're looking for? */
+
 		t = *q;
 		*q = '\0';
+
 		fpw = pw_scan(r, PWSCAN_MASTER);
+
+		/*
+		 * fpw is either the struct passwd for the current line,
+		 * or NULL if the line is malformed.
+		 */
+
 		*q = t;
-		if ((old_pw && !pw_equal(fpw, old_pw)) ||
-		    (!old_pw && strcmp(fpw->pw_name, pw->pw_name))) {
+		if (fpw == NULL || strcmp(fpw->pw_name, spw->pw_name) != 0) {
 			/* nope */
-			free(fpw);
+			if (fpw != NULL)
+				free(fpw);
 			if (write(tfd, p, q - p + 1) != q - p + 1)
 				goto err;
 			++q;
 			continue;
 		}
-		free(fpw);
-
-		/* it is, replace it */
-		len = strlen(line);
-		if (write(tfd, line, len) != len)
+		if (old_pw && !pw_equal(fpw, old_pw)) {
+			warnx("entry inconsistent");
+			free(fpw);
+			errno = EINVAL; /* hack */
 			goto err;
+		}
+		free(fpw);
 
+		/* it is, replace or remove it */
+		if (line != NULL) {
+			len = strlen(line);
+			if (write(tfd, line, len) != (int)len)
+				goto err;
+		} else {
+			/* when removed, avoid the \n */
+			q++;
+		}
 		/* we're done, just copy the rest over */
 		for (;;) {
 			if (write(tfd, q, end - q) != end - q)
 				goto err;
 			q = buf;
-			len = read(ffd, buf, sizeof buf);
-			if (len == 0)
+			readlen = read(ffd, buf, sizeof(buf));
+			if (readlen == 0)
 				break;
-			if (len == -1)
+			else
+				len = (size_t)readlen;
+			if (readlen == -1)
 				goto err;
 			end = buf + len;
 		}
 		goto done;
 	}
 
-	/* if we got here, we have a new entry */
+	/* if we got here, we didn't find the old entry */
+	if (line == NULL) {
+		errno = ENOENT;
+		goto err;
+	}
 	len = strlen(line);
-	if (write(tfd, line, len) != len ||
+	if ((size_t)write(tfd, line, len) != len ||
 	    write(tfd, "\n", 1) != 1)
 		goto err;
  done:
-	free(line);
+	if (line != NULL)
+		free(line);
 	return (0);
  err:
-	free(line);
+	if (line != NULL)
+		free(line);
 	return (-1);
 }
 
@@ -521,45 +591,52 @@ pw_tempname(void)
  * Duplicate a struct passwd.
  */
 struct passwd *
-pw_dup(struct passwd *pw)
+pw_dup(const struct passwd *pw)
 {
+	char *dst;
 	struct passwd *npw;
-	size_t len;
+	ssize_t len;
 
-	len = sizeof *npw +
-	    (pw->pw_name ? strlen(pw->pw_name) + 1 : 0) +
-	    (pw->pw_passwd ? strlen(pw->pw_passwd) + 1 : 0) +
-	    (pw->pw_class ? strlen(pw->pw_class) + 1 : 0) +
-	    (pw->pw_gecos ? strlen(pw->pw_gecos) + 1 : 0) +
-	    (pw->pw_dir ? strlen(pw->pw_dir) + 1 : 0) +
-	    (pw->pw_shell ? strlen(pw->pw_shell) + 1 : 0);
-	if ((npw = malloc(len)) == NULL)
+	len = sizeof(*npw);
+	if (pw->pw_name != NULL)
+		len += strlen(pw->pw_name) + 1;
+	if (pw->pw_passwd != NULL)
+		len += strlen(pw->pw_passwd) + 1;
+	if (pw->pw_class != NULL)
+		len += strlen(pw->pw_class) + 1;
+	if (pw->pw_gecos != NULL)
+		len += strlen(pw->pw_gecos) + 1;
+	if (pw->pw_dir != NULL)
+		len += strlen(pw->pw_dir) + 1;
+	if (pw->pw_shell != NULL)
+		len += strlen(pw->pw_shell) + 1;
+	if ((npw = malloc((size_t)len)) == NULL)
 		return (NULL);
-	memcpy(npw, pw, sizeof *npw);
-	len = sizeof *npw;
-	if (pw->pw_name) {
-		npw->pw_name = ((char *)npw) + len;
-		len += sprintf(npw->pw_name, "%s", pw->pw_name) + 1;
+	memcpy(npw, pw, sizeof(*npw));
+	dst = (char *)npw + sizeof(*npw);
+	if (pw->pw_name != NULL) {
+		npw->pw_name = dst;
+		dst = stpcpy(npw->pw_name, pw->pw_name) + 1;
 	}
-	if (pw->pw_passwd) {
-		npw->pw_passwd = ((char *)npw) + len;
-		len += sprintf(npw->pw_passwd, "%s", pw->pw_passwd) + 1;
+	if (pw->pw_passwd != NULL) {
+		npw->pw_passwd = dst;
+		dst = stpcpy(npw->pw_passwd, pw->pw_passwd) + 1;
 	}
-	if (pw->pw_class) {
-		npw->pw_class = ((char *)npw) + len;
-		len += sprintf(npw->pw_class, "%s", pw->pw_class) + 1;
+	if (pw->pw_class != NULL) {
+		npw->pw_class = dst;
+		dst = stpcpy(npw->pw_class, pw->pw_class) + 1;
 	}
-	if (pw->pw_gecos) {
-		npw->pw_gecos = ((char *)npw) + len;
-		len += sprintf(npw->pw_gecos, "%s", pw->pw_gecos) + 1;
+	if (pw->pw_gecos != NULL) {
+		npw->pw_gecos = dst;
+		dst = stpcpy(npw->pw_gecos, pw->pw_gecos) + 1;
 	}
-	if (pw->pw_dir) {
-		npw->pw_dir = ((char *)npw) + len;
-		len += sprintf(npw->pw_dir, "%s", pw->pw_dir) + 1;
+	if (pw->pw_dir != NULL) {
+		npw->pw_dir = dst;
+		dst = stpcpy(npw->pw_dir, pw->pw_dir) + 1;
 	}
-	if (pw->pw_shell) {
-		npw->pw_shell = ((char *)npw) + len;
-		len += sprintf(npw->pw_shell, "%s", pw->pw_shell) + 1;
+	if (pw->pw_shell != NULL) {
+		npw->pw_shell = dst;
+		dst = stpcpy(npw->pw_shell, pw->pw_shell) + 1;
 	}
 	return (npw);
 }