From 3e885fdaff115df3269a2770f0039ae50ec2c814 Mon Sep 17 00:00:00 2001
From: Jan Kadlec <jan@hp4-jankadlec.(none)>
Date: Sun, 14 Nov 2010 13:35:47 +0100
Subject: [PATCH] Few comments added. Strlcpy from FreeBSD.
---
src/dnslib/descriptor.c | 61 +++++++++++++++++++++++++++++++++++++++--
src/dnslib/descriptor.h | 48 ++++++++++++++++++++++++++++++++
2 files changed, 106 insertions(+), 3 deletions(-)
diff --git a/src/dnslib/descriptor.c b/src/dnslib/descriptor.c
index a6f319353..d9f5752b1 100644
--- a/src/dnslib/descriptor.c
+++ b/src/dnslib/descriptor.c
@@ -10,6 +10,9 @@
#include <string.h>
#include <stdio.h>
#include <ctype.h>
+#include <assert.h>
+#include <string.h>
+#include <sys/types.h>
#include "descriptor.h"
@@ -19,6 +22,15 @@
const uint16_t DNSLIB_PSEUDO_TYPE_DLV = 32769;
+/* Taken from RFC 1035, section 3.2.4. */
+static lookup_table_type dns_rrclasses[] = {
+ { DNSLIB_CLASS_IN, "IN" }, /* the Internet */
+ { DNSLIB_CLASS_CS, "CS" }, /* the CSNET class (Obsolete) */
+ { DNSLIB_CLASS_CH, "CH" }, /* the CHAOS class */
+ { DNSLIB_CLASS_HS, "HS" }, /* Hesiod */
+ { 0, NULL }
+};
+
static dnslib_rrtype_descriptor_t dnslib_rrtype_descriptors[101] = { //XXX magic constant
/* 0 */
{ 0, NULL, 1, { DNSLIB_RDATA_WF_BINARY } },
@@ -243,6 +255,50 @@ static dnslib_rrtype_descriptor_t dnslib_rrtype_descriptors[101] = { //XXX magic
{ DNSLIB_RDATA_WF_SHORT, DNSLIB_RDATA_WF_BYTE, DNSLIB_RDATA_WF_BYTE, DNSLIB_RDATA_WF_BINARY } },*/
};
+lookup_table_type *lookup_by_name(lookup_table_type *table, const char *name)
+{
+ while (table->name != NULL) {
+ if (strcasecmp(name, table->name) == 0)
+ return table;
+ table++;
+ }
+ return NULL;
+}
+
+lookup_table_type *lookup_by_id(lookup_table_type *table, int id)
+{
+ while (table->name != NULL) {
+ if (table->id == id)
+ return table;
+ table++;
+ }
+ return NULL;
+}
+
+size_t strlcpy(char *dst, const char *src, size_t siz)
+{
+ char *d = dst;
+ const char *s = src;
+ size_t n = siz;
+
+ /* Copy as many bytes as will fit */
+ if (n != 0 && --n != 0) {
+ do {
+ if ((*d++ = *s++) == 0)
+ break;
+ } while (--n != 0);
+ }
+
+ /* Not enough room in dst, add NUL and traverse rest of src */
+ if (n == 0) {
+ if (siz != 0)
+ *d = '\0'; /* NUL-terminate dst */
+ while (*s++)
+ ;
+ }
+ return(s - src - 1); /* count does not include NUL */
+}
+
dnslib_rrtype_descriptor_t *dnslib_rrtype_descriptor_by_type(uint16_t type)
{
if (type < DNSLIB_RRTYPE_DESCRIPTORS_LENGTH)
@@ -322,13 +378,13 @@ uint16_t rrtype_from_string(const char *name)
return (uint16_t) rrtype;
}
-/*const char *rrclass_to_string(uint16_t rrclass)
+const char *rrclass_to_string(uint16_t rrclass)
{
static char buf[20];
lookup_table_type *entry = lookup_by_id(dns_rrclasses, rrclass);
if (entry) {
assert(strlen(entry->name) < sizeof(buf));
- strlcpy(buf, entry->name, sizeof(buf));
+ strlcpy(buf, entry->name, sizeof(buf));
} else {
snprintf(buf, sizeof(buf), "CLASS%d", (int) rrclass);
}
@@ -365,5 +421,4 @@ uint16_t rrclass_from_string(const char *name)
return (uint16_t) rrclass;
}
-*/
/* end of file descriptor.c */
diff --git a/src/dnslib/descriptor.h b/src/dnslib/descriptor.h
index 41bbc7571..5521c416c 100644
--- a/src/dnslib/descriptor.h
+++ b/src/dnslib/descriptor.h
@@ -18,6 +18,30 @@
#define MAXRDATALEN 64
/* 64 is in NSD. Seems a little too much, but I'd say it's not a real issue. */
+/* A general purpose lookup table */
+typedef struct lookup_table lookup_table_type;
+struct lookup_table {
+ int id;
+ const char *name;
+};
+
+enum dnslib_rr_class
+{
+ DNSLIB_CLASS_IN,
+ DNSLIB_CLASS_CS,
+ DNSLIB_CLASS_CH,
+ DNSLIB_CLASS_HS,
+ DNSLIB_CLASS_NONE = 254,
+ DNSLIB_CLASS_ANY = 255
+};
+
+/*!
+ * \brief Enum containing RR type codes.
+ *
+ * \todo Not all indices can be used for indexing.
+ */
+typedef enum dnslib_rr_class dnslib_rr_class_t;
+
enum dnslib_rr_type
{
DNSLIB_RRTYPE_UNKNOWN, /* 0 - an unknown type */
@@ -92,6 +116,11 @@ enum dnslib_rr_type
DNSLIB_RRTYPE_DLV = 32769/* RFC 4431 */
};
+/*!
+ * \brief Enum containing RR type codes.
+ *
+ * \todo Not all indices can be used for indexing.
+ */
typedef enum dnslib_rr_type dnslib_rr_type_t;
enum dnslib_rdata_wireformat
@@ -111,6 +140,9 @@ enum dnslib_rdata_wireformat
DNSLIB_RDATA_WF_IPSECGATEWAY /* IPSECKEY gateway ip4, ip6 or dname. */
};
+/*!
+ * \brief Enum containing wireformat codes. Taken from NSD's "dns.h"
+ */
typedef enum dnslib_rdatawireformat dnslib_rdata_wireformat_t;
struct dnslib_rrtype_descriptor
@@ -121,8 +153,24 @@ struct dnslib_rrtype_descriptor
uint8_t wireformat[MAXRDATALEN]; /* rdata_wireformat_type */
};
+/*!
+ * \brief Structure holding RR descriptor
+ */
typedef struct dnslib_rrtype_descriptor dnslib_rrtype_descriptor_t;
+/*!
+ * \brief Strlcpy - safe string copy function, based on FreeBDS implementation
+ *
+ * http://www.openbsd.org/cgi-bin/cvsweb/src/lib/libc/string/
+ *
+ * \param dst Destination string.
+ * \param src Source string.
+ * \param siz How many characters to copy - 1.
+ *
+ * \return strlen(src), if retval >= siz, truncation occurred.
+ */
+size_t strlcpy( char *dst, const char *src, size_t siz );
+
#endif
/* end of file descriptor.h */
--
GitLab