1 files changed, 113 insertions, 38 deletions

diff --git a/util/libreboot-utils/lib/string.c b/util/libreboot-utils/lib/string.c
index ea7ca30a..0329c6c3 100644
--- a/util/libreboot-utils/lib/string.c
+++ b/util/libreboot-utils/lib/string.c
@@ -14,25 +14,12 @@
 #include <string.h>
 #include <stdlib.h>
 #include <unistd.h>
+#include <limits.h>
+#include <stdint.h>
 
 #include "../include/common.h"
 
-/* scmp() - strict string comparison
- *
- * strict string comparison
- * similar to strncmp, but null and
- * unterminated inputs do not produce
- * a return value; on error, errno is
- * set and -1 is returned.
- *
- * the real return value is stored in
- * the 4th argument by pointer.
- *
- * the value at rval pointer is set,
- * only upon success. callers should
- * check the return value accordingly.
- */
-
+/* strict strcmp */
 int
 scmp(const char *a,
     const char *b,
@@ -46,9 +33,8 @@ scmp(const char *a,
 	if (a == NULL ||
 	    b == NULL ||
 	    rval == NULL) {
-
 		errno = EFAULT;
-		return -1;
+		goto err;
 	}
 
 	for (ch = 0; ch < maxlen; ch++) {
@@ -67,27 +53,14 @@ scmp(const char *a,
 		}
 	}
 
-	/* block unterminated strings */
+err:
 	errno = EFAULT;
+	if (rval != NULL)
+		*rval = -1;
 	return -1;
 }
 
-/* slen() - strict strict length
- *
- * strict string length calculation
- * similar to strnlen, but null and
- * unterminated inputs do not produce
- * a return value; on error, errno is
- * set and -1 is returned.
- *
- * the real return value is stored in
- * the 3rd argument by pointer.
- *
- * the value at rval pointer is set,
- * only upon success. callers should
- * check the return value accordingly.
- */
-
+/* strict strlen */
 int
 slen(const char *s,
     size_t maxlen,
@@ -97,9 +70,8 @@ slen(const char *s,
 
 	if (s == NULL ||
 	    rval == NULL) {
-
 		errno = EFAULT;
-		return -1;
+		goto err;
 	}
 
 	for (ch = 0;
@@ -109,11 +81,114 @@ slen(const char *s,
 	if (ch == maxlen) {
 		/* unterminated */
 		errno = EFAULT;
-		return -1;
+		goto err;
 	}
 
 	*rval = ch;
 	return 0;
+err:
+	if (rval != NULL)
+		*rval = 0;
+	return -1;
+}
+
+/* strict strdup */
+int
+sdup(const char *s,
+    size_t n, char **dest)
+{
+	size_t size;
+	char *rval;
+
+	if (dest == NULL ||
+	    slen(s, n, &size) < 0 ||
+	    if_err(size == SIZE_MAX, EOVERFLOW) ||
+	    (rval = malloc(size + 1)) == NULL) {
+
+		if (dest != NULL)
+			*dest = NULL;
+		return -1;
+	}
+
+	memcpy(rval, s, size);
+	*(rval + size) = '\0';
+
+	*dest = rval;
+	return 0;
+}
+
+/* strict strcat */
+int
+scat(const char *s1, const char *s2,
+    size_t n, char **dest)
+{
+	size_t size1;
+	size_t size2;
+	char *rval;
+
+	if (dest == NULL ||
+	    slen(s1, n, &size1) < 0 ||
+	    slen(s2, n, &size2) < 0 ||
+	    if_err(size1 > SIZE_MAX - size2 - 1, EOVERFLOW) ||
+	    (rval = malloc(size1 + size2 + 1)) == NULL) {
+
+		if (dest != NULL)
+			*dest = NULL;
+		return -1;
+	}
+
+	memcpy(rval, s1, size1);
+	memcpy(rval + size1, s2, size2);
+	*(rval + size1 + size2) = '\0';
+
+	*dest = rval;
+	return 0;
+}
+
+/* strict split/de-cat - off is where
+   2nd buffer will start from */
+int
+dcat(const char *s, size_t n,
+    size_t off, char **dest1,
+    char **dest2)
+{
+	size_t size;
+	char *rval1 = NULL;
+	char *rval2 = NULL;
+
+	if (dest1 == NULL || dest2 == NULL ||
+	    slen(s, n, &size) < 0 ||
+	    if_err(size == SIZE_MAX, EOVERFLOW) ||
+	    if_err(off >= size, EOVERFLOW) ||
+	    (rval1 = malloc(off + 1)) == NULL ||
+	    (rval2 = malloc(size - off + 1)) == NULL) {
+
+		goto err;
+	}
+
+	memcpy(rval1, s, off);
+	*(rval1 + off) = '\0';
+
+	memcpy(rval2, s + off, size - off);
+	*(rval2 + size - off) = '\0';
+
+	*dest1 = rval1;
+	*dest2 = rval2;
+
+	return 0;
+
+err:
+	if (rval1 != NULL)
+		free(rval1);
+	if (rval2 != NULL)
+		free(rval2);
+
+	if (dest1 != NULL)
+		*dest1 = NULL;
+	if (dest2 != NULL)
+		*dest2 = NULL;
+
+	return -1;
 }
 
 /* the one for nvmutil state is in state.c */