Error out if gen finds a type or class that is greater than 65535

diff --git a/lib/dns/gen.c b/lib/dns/gen.c
index 6e65310df770e4c9d0603dd8061d05ed279b044a..67150597d3fcdc68df856fe8f3768e2e4a8857b6 100644 (file)
--- a/lib/dns/gen.c
+++ b/lib/dns/gen.c
@@ -127,7 +127,7 @@ static const char copyright[] = "/*\n"
 #define TYPENAMES     256
 #define TYPECLASSLEN  20 /* DNS mnemonic size. Must be less than 100. */
 #define TYPECLASSBUF  (TYPECLASSLEN + 1)
-#define TYPECLASSFMT  "%" STR(TYPECLASSLEN) "[-0-9a-z]_%d"
+#define TYPECLASSFMT  "%" STR(TYPECLASSLEN) "[-0-9a-z]_%u"
 #define ATTRIBUTESIZE 256
 
 static struct cc {
@@ -163,9 +163,9 @@ static void
 doswitch(const char *, const char *, const char *, const char *, const char *,
         const char *);
 static void
-add(int, const char *, int, const char *, const char *);
+add(unsigned int, const char *, int, const char *, const char *);
 static void
-sd(int, const char *, const char *, char);
+sd(unsigned int, const char *, const char *, char);
 static void
 insert_into_typenames(int, const char *, const char *);
 
@@ -370,7 +370,7 @@ insert_into_typenames(int type, const char *typebuf, const char *attr) {
 }
 
 static void
-add(int rdclass, const char *classbuf, int type, const char *typebuf,
+add(unsigned int rdclass, const char *classbuf, int type, const char *typebuf,
     const char *dirbuf) {
        struct tt *newtt = (struct tt *)malloc(sizeof(*newtt));
        struct tt *tt, *oldtt;
@@ -468,10 +468,12 @@ add(int rdclass, const char *classbuf, int type, const char *typebuf,
 }
 
 static void
-sd(int rdclass, const char *classbuf, const char *dirbuf, char filetype) {
-       char buf[TYPECLASSLEN + sizeof("_65535.h")];
+sd(unsigned int rdclass, const char *classbuf, const char *dirbuf,
+   char filetype) {
+       char buf[TYPECLASSLEN + sizeof("_4294967295.h")];
        char typebuf[TYPECLASSBUF];
-       int type, n;
+       unsigned int type;
+       int n;
        isc_dir_t dir;
 
        if (!start_directory(dirbuf, &dir)) {
@@ -482,16 +484,23 @@ sd(int rdclass, const char *classbuf, const char *dirbuf, char filetype) {
                if (sscanf(dir.filename, TYPECLASSFMT, typebuf, &type) != 2) {
                        continue;
                }
-               if ((type > 65535) || (type < 0)) {
-                       continue;
-               }
 
-               n = snprintf(buf, sizeof(buf), "%s_%d.%c", typebuf, type,
+               /*
+                * sscanf accepts leading sign and zeros before type so
+                * compare the scanned items against the filename. Filter
+                * out mismatches. Also filter out bad file extensions.
+                */
+               n = snprintf(buf, sizeof(buf), "%s_%u.%c", typebuf, type,
                             filetype);
                INSIST(n > 0 && (unsigned)n < sizeof(buf));
                if (strcmp(buf, dir.filename) != 0) {
                        continue;
                }
+               if (type > 65535) {
+                       fprintf(stderr, "Error: type value > 65535 (%s)\n",
+                               dir.filename);
+                       exit(1);
+               }
                add(rdclass, classbuf, type, typebuf, dirbuf);
        }
 
@@ -518,7 +527,7 @@ int
 main(int argc, char **argv) {
        char buf[PATH_MAX];
        char srcdir[PATH_MAX];
-       int rdclass;
+       unsigned int rdclass;
        char classbuf[TYPECLASSBUF];
        struct tt *tt;
        struct cc *cc;
@@ -622,16 +631,23 @@ main(int argc, char **argv) {
                {
                        continue;
                }
-               if ((rdclass > 65535) || (rdclass < 0)) {
-                       continue;
-               }
 
-               n = snprintf(buf, sizeof(buf), "%srdata/%s_%d", srcdir,
+               /*
+                * sscanf accepts leading sign and zeros before type so
+                * compare the scanned items against the filename. Filter
+                * out mismatches.
+                */
+               n = snprintf(buf, sizeof(buf), "%srdata/%s_%u", srcdir,
                             classbuf, rdclass);
                INSIST(n > 0 && (unsigned)n < sizeof(buf));
                if (strcmp(buf + 6 + strlen(srcdir), dir.filename) != 0) {
                        continue;
                }
+               if (rdclass > 65535) {
+                       fprintf(stderr, "Error: class value > 65535 (%s)\n",
+                               dir.filename);
+                       exit(1);
+               }
                sd(rdclass, classbuf, buf, filetype);
        }
        end_directory(&dir);