Add stpcpy/stpncpy.

Add tests for the above.

Add the fortify implementations of __stpcpy_chk and __stpncpy_chk.

Modify the strncpy test to cover more cases and use this template for
stpncpy.

Add all of the fortify test cases.

Bug: 13746695
Change-Id: I8c0f0d4991a878b8e8734fff12c8b73b07fdd344
diff --git a/libc/Android.mk b/libc/Android.mk
index 44bf388..3eaff2f 100644
--- a/libc/Android.mk
+++ b/libc/Android.mk
@@ -96,6 +96,8 @@
     bionic/__memmove_chk.cpp \
     bionic/__read_chk.cpp \
     bionic/__recvfrom_chk.cpp \
+    bionic/__stpcpy_chk.cpp \
+    bionic/__stpncpy_chk.cpp \
     bionic/__strchr_chk.cpp \
     bionic/__strlcat_chk.cpp \
     bionic/__strlcpy_chk.cpp \
@@ -383,6 +385,8 @@
     upstream-openbsd/lib/libc/stdlib/strtoull.c \
     upstream-openbsd/lib/libc/stdlib/strtoumax.c \
     upstream-openbsd/lib/libc/stdlib/system.c \
+    upstream-openbsd/lib/libc/string/stpcpy.c \
+    upstream-openbsd/lib/libc/string/stpncpy.c \
     upstream-openbsd/lib/libc/string/strcasecmp.c \
     upstream-openbsd/lib/libc/string/strcspn.c \
     upstream-openbsd/lib/libc/string/strdup.c \
diff --git a/libc/bionic/__stpcpy_chk.cpp b/libc/bionic/__stpcpy_chk.cpp
new file mode 100644
index 0000000..3ce81ee
--- /dev/null
+++ b/libc/bionic/__stpcpy_chk.cpp
@@ -0,0 +1,55 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * 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 COPYRIGHT HOLDERS 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
+ * COPYRIGHT OWNER 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.
+ */
+
+#undef _FORTIFY_SOURCE
+
+#include <string.h>
+#include <stdlib.h>
+#include "private/libc_logging.h"
+
+/*
+ * Runtime implementation of __builtin____stpcpy_chk.
+ *
+ * See
+ *   http://gcc.gnu.org/onlinedocs/gcc/Object-Size-Checking.html
+ *   http://gcc.gnu.org/ml/gcc-patches/2004-09/msg02055.html
+ * for details.
+ *
+ * This stpcpy check is called if _FORTIFY_SOURCE is defined and
+ * greater than 0.
+ */
+extern "C" char* __stpcpy_chk(char* dest, const char* src, size_t dest_len) {
+  // TODO: optimize so we don't scan src twice.
+  size_t src_len = strlen(src) + 1;
+  if (__predict_false(src_len > dest_len)) {
+    __fortify_chk_fail("stpcpy: prevented write past end of buffer",
+                       BIONIC_EVENT_STPCPY_BUFFER_OVERFLOW);
+  }
+
+  return stpcpy(dest, src);
+}
diff --git a/libc/bionic/__stpncpy_chk.cpp b/libc/bionic/__stpncpy_chk.cpp
new file mode 100644
index 0000000..6c9215c
--- /dev/null
+++ b/libc/bionic/__stpncpy_chk.cpp
@@ -0,0 +1,92 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * 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 COPYRIGHT HOLDERS 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
+ * COPYRIGHT OWNER 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.
+ */
+
+#undef _FORTIFY_SOURCE
+
+#include <string.h>
+#include <stdlib.h>
+#include "private/libc_logging.h"
+
+/*
+ * Runtime implementation of __builtin____stpncpy_chk.
+ *
+ * See
+ *   http://gcc.gnu.org/onlinedocs/gcc/Object-Size-Checking.html
+ *   http://gcc.gnu.org/ml/gcc-patches/2004-09/msg02055.html
+ * for details.
+ *
+ * This stpncpy check is called if _FORTIFY_SOURCE is defined and
+ * greater than 0.
+ */
+extern "C" char* __stpncpy_chk(char* __restrict dest, const char* __restrict src,
+                               size_t len, size_t dest_len) {
+  if (__predict_false(len > dest_len)) {
+    __fortify_chk_fail("stpncpy: prevented write past end of buffer",
+                       BIONIC_EVENT_STPNCPY_BUFFER_OVERFLOW);
+  }
+
+  return stpncpy(dest, src, len);
+}
+
+/*
+ * __stpncpy_chk2
+ *
+ * This is a variant of __stpncpy_chk, but it also checks to make
+ * sure we don't read beyond the end of "src". The code for this is
+ * based on the original version of stpncpy, but modified to check
+ * how much we read from "src" at the end of the copy operation.
+ */
+extern "C" char* __stpncpy_chk2(char* __restrict dst, const char* __restrict src,
+              size_t n, size_t dest_len, size_t src_len)
+{
+  if (__predict_false(n > dest_len)) {
+    __fortify_chk_fail("stpncpy: prevented write past end of buffer",
+                       BIONIC_EVENT_STPNCPY_BUFFER_OVERFLOW);
+  }
+  if (n != 0) {
+    char* d = dst;
+    const char* s = src;
+
+    do {
+      if ((*d++ = *s++) == 0) {
+        /* NUL pad the remaining n-1 bytes */
+        while (--n != 0) {
+          *d++ = 0;
+        }
+        break;
+      }
+    } while (--n != 0);
+
+    size_t s_copy_len = static_cast<size_t>(s - src);
+    if (__predict_false(s_copy_len > src_len)) {
+      __fortify_chk_fail("stpncpy: prevented read past end of buffer", 0);
+    }
+  }
+
+  return dst;
+}
diff --git a/libc/bionic/__strcpy_chk.cpp b/libc/bionic/__strcpy_chk.cpp
index 1f6bc80..ad3ef50 100644
--- a/libc/bionic/__strcpy_chk.cpp
+++ b/libc/bionic/__strcpy_chk.cpp
@@ -26,6 +26,8 @@
  * SUCH DAMAGE.
  */
 
+#undef _FORTIFY_SOURCE
+
 #include <string.h>
 #include <stdlib.h>
 #include "private/libc_logging.h"
@@ -41,7 +43,7 @@
  * This strcpy check is called if _FORTIFY_SOURCE is defined and
  * greater than 0.
  */
-extern "C" char* __strcpy_chk (char* dest, const char* src, size_t dest_len) {
+extern "C" char* __strcpy_chk(char* dest, const char* src, size_t dest_len) {
   // TODO: optimize so we don't scan src twice.
   size_t src_len = strlen(src) + 1;
   if (__predict_false(src_len > dest_len)) {
diff --git a/libc/include/string.h b/libc/include/string.h
index ec998ed..c9ae03b 100644
--- a/libc/include/string.h
+++ b/libc/include/string.h
@@ -53,6 +53,7 @@
 extern size_t strlen(const char *) __purefunc;
 extern size_t __strlen_chk(const char *, size_t);
 extern int    strcmp(const char *, const char *) __purefunc;
+extern char*  stpcpy(char* __restrict, const char* __restrict);
 extern char*  strcpy(char* __restrict, const char* __restrict);
 extern char*  strcat(char* __restrict, const char* __restrict);
 
@@ -72,6 +73,7 @@
 extern char*  strncat(char* __restrict, const char* __restrict, size_t);
 extern char*  strndup(const char *, size_t);
 extern int    strncmp(const char *, const char *, size_t) __purefunc;
+extern char*  stpncpy(char* __restrict, const char* __restrict, size_t);
 extern char*  strncpy(char* __restrict, const char* __restrict, size_t);
 
 extern size_t strlcat(char* __restrict, const char* __restrict, size_t);
@@ -89,8 +91,8 @@
 
 #if defined(__BIONIC_FORTIFY)
 
-__errordecl(__memcpy_dest_size_error, "memcpy called with size bigger than destination");
-__errordecl(__memcpy_src_size_error, "memcpy called with size bigger than source");
+__errordecl(__memcpy_dest_size_error, "memcpy: prevented write past end of buffer");
+__errordecl(__memcpy_src_size_error, "memcpy: prevented read past end of buffer");
 
 __BIONIC_FORTIFY_INLINE
 void* memcpy(void* __restrict dest, const void* __restrict src, size_t copy_amount) {
@@ -116,11 +118,43 @@
 }
 
 __BIONIC_FORTIFY_INLINE
+char* stpcpy(char* __restrict dest, const char* __restrict src) {
+    return __builtin___stpcpy_chk(dest, src, __bos(dest));
+}
+
+__BIONIC_FORTIFY_INLINE
 char* strcpy(char* __restrict dest, const char* __restrict src) {
     return __builtin___strcpy_chk(dest, src, __bos(dest));
 }
 
-__errordecl(__strncpy_error, "strncpy called with size bigger than buffer");
+__errordecl(__stpncpy_error, "stpncpy: prevented write past end of buffer");
+extern char* __stpncpy_chk2(char* __restrict, const char* __restrict, size_t, size_t, size_t);
+
+__BIONIC_FORTIFY_INLINE
+char* stpncpy(char* __restrict dest, const char* __restrict src, size_t n) {
+    size_t bos_dest = __bos(dest);
+    size_t bos_src = __bos(src);
+    if (__builtin_constant_p(n) && (n > bos_dest)) {
+        __stpncpy_error();
+    }
+
+    if (bos_src == __BIONIC_FORTIFY_UNKNOWN_SIZE) {
+        return __builtin___stpncpy_chk(dest, src, n, bos_dest);
+    }
+
+    if (__builtin_constant_p(n) && (n <= bos_src)) {
+        return __builtin___stpncpy_chk(dest, src, n, bos_dest);
+    }
+
+    size_t slen = __builtin_strlen(src);
+    if (__builtin_constant_p(slen)) {
+        return __builtin___stpncpy_chk(dest, src, n, bos_dest);
+    }
+
+    return __stpncpy_chk2(dest, src, n, bos_dest, bos_src);
+}
+
+__errordecl(__strncpy_error, "strncpy: prevented write past end of buffer");
 extern char* __strncpy_chk2(char* __restrict, const char* __restrict, size_t, size_t, size_t);
 
 __BIONIC_FORTIFY_INLINE
@@ -164,7 +198,7 @@
 
 extern size_t __strlcpy_real(char* __restrict, const char* __restrict, size_t)
     __asm__(__USER_LABEL_PREFIX__ "strlcpy");
-__errordecl(__strlcpy_error, "strlcpy called with size bigger than buffer");
+__errordecl(__strlcpy_error, "strlcpy: prevented write past end of buffer");
 extern size_t __strlcpy_chk(char *, const char *, size_t, size_t);
 
 __BIONIC_FORTIFY_INLINE
@@ -195,7 +229,7 @@
 
 extern size_t __strlcat_real(char* __restrict, const char* __restrict, size_t)
     __asm__(__USER_LABEL_PREFIX__ "strlcat");
-__errordecl(__strlcat_error, "strlcat called with size bigger than buffer");
+__errordecl(__strlcat_error, "strlcat: prevented write past end of buffer");
 extern size_t __strlcat_chk(char* __restrict, const char* __restrict, size_t, size_t);
 
 
diff --git a/libc/private/libc_events.h b/libc/private/libc_events.h
index 5d20f4b..f2b973d 100644
--- a/libc/private/libc_events.h
+++ b/libc/private/libc_events.h
@@ -40,6 +40,8 @@
 #define BIONIC_EVENT_STRNCPY_BUFFER_OVERFLOW  80120
 #define BIONIC_EVENT_MEMSET_BUFFER_OVERFLOW   80125
 #define BIONIC_EVENT_STRCPY_BUFFER_OVERFLOW   80130
+#define BIONIC_EVENT_STPCPY_BUFFER_OVERFLOW   80135
+#define BIONIC_EVENT_STPNCPY_BUFFER_OVERFLOW  80140
 
 #define BIONIC_EVENT_RESOLVER_OLD_RESPONSE    80300
 #define BIONIC_EVENT_RESOLVER_WRONG_SERVER    80305
diff --git a/libc/upstream-openbsd/lib/libc/string/stpcpy.c b/libc/upstream-openbsd/lib/libc/string/stpcpy.c
new file mode 100644
index 0000000..d3d61e0
--- /dev/null
+++ b/libc/upstream-openbsd/lib/libc/string/stpcpy.c
@@ -0,0 +1,44 @@
+/*	$OpenBSD: stpcpy.c,v 1.1 2012/01/17 02:48:01 guenther Exp $	*/
+
+/*
+ * Copyright (c) 1988 Regents of the University of California.
+ * 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.
+ * 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.
+ */
+
+#include <string.h>
+
+#if defined(APIWARN)
+__warn_references(stpcpy,
+    "warning: stpcpy() is dangerous GNU crap; don't use it");
+#endif
+
+char *
+stpcpy(char *to, const char *from)
+{
+	for (; (*to = *from) != '\0'; ++from, ++to);
+	return(to);
+}
diff --git a/libc/upstream-openbsd/lib/libc/string/stpncpy.c b/libc/upstream-openbsd/lib/libc/string/stpncpy.c
new file mode 100644
index 0000000..c7c2a57
--- /dev/null
+++ b/libc/upstream-openbsd/lib/libc/string/stpncpy.c
@@ -0,0 +1,56 @@
+/*	$OpenBSD: stpncpy.c,v 1.2 2012/07/11 10:44:59 naddy Exp $	*/
+
+/*-
+ * Copyright (c) 1990 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Chris Torek.
+ *
+ * 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.
+ */
+
+#include <string.h>
+
+char *
+stpncpy(char *dst, const char *src, size_t n)
+{
+	if (n != 0) {
+		char *d = dst;
+		const char *s = src;
+
+		dst = &dst[n];
+		do {
+			if ((*d++ = *s++) == 0) {
+				dst = d - 1;
+				/* NUL pad the remaining n-1 bytes */
+				while (--n != 0)
+					*d++ = 0;
+				break;
+			}
+		} while (--n != 0);
+	}
+	return (dst);
+}