X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=src%2Fpasswd%2Fgetspnam_r.c;h=541e85314d56cc36d7b752ec9693563390ca07b2;hb=0ea78a6421322cab24d448670006ee2f99af3ac9;hp=9e29aa9cf78d782d4c17a93d7e2f9042fba44ab9;hpb=18bca575107d80ca81241d1429ded62918c5bd2e;p=musl

diff --git a/src/passwd/getspnam_r.c b/src/passwd/getspnam_r.c
index 9e29aa9c..541e8531 100644
--- a/src/passwd/getspnam_r.c
+++ b/src/passwd/getspnam_r.c
@@ -2,6 +2,7 @@
 #include <unistd.h>
 #include <sys/stat.h>
 #include <ctype.h>
+#include <pthread.h>
 #include "pwf.h"
 
 /* This implementation support Openwall-style TCB passwords in place of
@@ -11,9 +12,50 @@
  * file. It also avoids any allocation to prevent memory-exhaustion
  * attacks via huge TCB shadow files. */
 
-static long xatol(const char *s)
+static long xatol(char **s)
 {
-	return isdigit(*s) ? atol(s) : -1;
+	long x;
+	if (**s == ':' || **s == '\n') return -1;
+	for (x=0; **s-'0'<10U; ++*s) x=10*x+(**s-'0');
+	return x;
+}
+
+int __parsespent(char *s, struct spwd *sp)
+{
+	sp->sp_namp = s;
+	if (!(s = strchr(s, ':'))) return -1;
+	*s = 0;
+
+	sp->sp_pwdp = ++s;
+	if (!(s = strchr(s, ':'))) return -1;
+	*s = 0;
+
+	s++; sp->sp_lstchg = xatol(&s);
+	if (*s != ':') return -1;
+
+	s++; sp->sp_min = xatol(&s);
+	if (*s != ':') return -1;
+
+	s++; sp->sp_max = xatol(&s);
+	if (*s != ':') return -1;
+
+	s++; sp->sp_warn = xatol(&s);
+	if (*s != ':') return -1;
+
+	s++; sp->sp_inact = xatol(&s);
+	if (*s != ':') return -1;
+
+	s++; sp->sp_expire = xatol(&s);
+	if (*s != ':') return -1;
+
+	s++; sp->sp_flag = xatol(&s);
+	if (*s != '\n') return -1;
+	return 0;
+}
+
+static void cleanup(void *p)
+{
+	fclose(p);
 }
 
 int getspnam_r(const char *name, struct spwd *sp, char *buf, size_t size, struct spwd **res)
@@ -23,37 +65,48 @@ int getspnam_r(const char *name, struct spwd *sp, char *buf, size_t size, struct
 	int rv = 0;
 	int fd;
 	size_t k, l = strlen(name);
-	char *s;
 	int skip = 0;
+	int cs;
+	int orig_errno = errno;
 
 	*res = 0;
 
 	/* Disallow potentially-malicious user names */
 	if (*name=='.' || strchr(name, '/') || !l)
-		return EINVAL;
+		return errno = EINVAL;
 
 	/* Buffer size must at least be able to hold name, plus some.. */
-	if (size < l+100) return ERANGE;
+	if (size < l+100)
+		return errno = ERANGE;
 
 	/* Protect against truncation */
 	if (snprintf(path, sizeof path, "/etc/tcb/%s/shadow", name) >= sizeof path)
-		return EINVAL;
+		return errno = EINVAL;
 
-	fd = open(path, O_RDONLY|O_NOFOLLOW|O_NONBLOCK);
+	fd = open(path, O_RDONLY|O_NOFOLLOW|O_NONBLOCK|O_CLOEXEC);
 	if (fd >= 0) {
 		struct stat st = { 0 };
 		errno = EINVAL;
 		if (fstat(fd, &st) || !S_ISREG(st.st_mode) || !(f = fdopen(fd, "rb"))) {
+			pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
 			close(fd);
+			pthread_setcancelstate(cs, 0);
 			return errno;
 		}
 	} else {
-		f = fopen("/etc/shadow", "rb");
-		if (!f) return errno;
+		if (errno != ENOENT && errno != ENOTDIR)
+			return errno;
+		f = fopen("/etc/shadow", "rbe");
+		if (!f) {
+			if (errno != ENOENT && errno != ENOTDIR)
+				return errno;
+			return 0;
+		}
 	}
 
+	pthread_cleanup_push(cleanup, f);
 	while (fgets(buf, size, f) && (k=strlen(buf))>0) {
-		if (skip || strncmp(name, buf, l)) {
+		if (skip || strncmp(name, buf, l) || buf[l]!=':') {
 			skip = buf[k-1] != '\n';
 			continue;
 		}
@@ -61,37 +114,12 @@ int getspnam_r(const char *name, struct spwd *sp, char *buf, size_t size, struct
 			rv = ERANGE;
 			break;
 		}
-		buf[k-1] = 0;
-
-		s = buf;
-		sp->sp_namp = s;
-		if (!(s = strchr(s, ':'))) continue;
-
-		*s++ = 0; sp->sp_pwdp = s;
-		if (!(s = strchr(s, ':'))) continue;
-
-		*s++ = 0; sp->sp_lstchg = xatol(s);
-		if (!(s = strchr(s, ':'))) continue;
-
-		*s++ = 0; sp->sp_min = xatol(s);
-		if (!(s = strchr(s, ':'))) continue;
-
-		*s++ = 0; sp->sp_max = xatol(s);
-		if (!(s = strchr(s, ':'))) continue;
-
-		*s++ = 0; sp->sp_warn = xatol(s);
-		if (!(s = strchr(s, ':'))) continue;
-
-		*s++ = 0; sp->sp_inact = xatol(s);
-		if (!(s = strchr(s, ':'))) continue;
-
-		*s++ = 0; sp->sp_expire = xatol(s);
-		if (!(s = strchr(s, ':'))) continue;
 
-		*s++ = 0; sp->sp_flag = xatol(s);
+		if (__parsespent(buf, sp) < 0) continue;
 		*res = sp;
 		break;
 	}
-	fclose(f);
+	pthread_cleanup_pop(1);
+	errno = rv ? rv : orig_errno;
 	return rv;
 }