mktag.c: tweak validation of tagger field and adjust test script

Update the verify_tag() function to remove an unnecessary test, and add
additional check for angle brackets in the name and email field, and
spaces in the email field. The timestamp and timezone sections are made
more straight forward by using strspn().

Signed-off-by: Brandon Casey <casey@nrlssc.navy.mil>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 14 insertions, 15 deletions

diff --git a/mktag.c b/mktag.c
index 8887080a6..0b34341f7 100644
--- a/mktag.c
+++ b/mktag.c
@@ -45,6 +45,7 @@ static int verify_tag(char *buffer, unsigned long size)
 	char type[20];
 	unsigned char sha1[20];
 	const char *object, *type_line, *tag_line, *tagger_line, *lb, *rb;
+	size_t len;
 
 	if (size < 84)
 		return error("wanna fool me ? you obviously got the size wrong !");
@@ -98,18 +99,21 @@ static int verify_tag(char *buffer, unsigned long size)
 	/* Verify the tagger line */
 	tagger_line = tag_line;
 
-	if (memcmp(tagger_line, "tagger ", 7) || (tagger_line[7] == '\n'))
+	if (memcmp(tagger_line, "tagger ", 7))
 		return error("char" PD_FMT ": could not find \"tagger \"",
 			tagger_line - buffer);
 
 	/*
 	 * Check for correct form for name and email
 	 * i.e. " <" followed by "> " on _this_ line
+	 * No angle brackets within the name or email address fields.
+	 * No spaces within the email address field.
 	 */
 	tagger_line += 7;
 	if (!(lb = strstr(tagger_line, " <")) || !(rb = strstr(lb+2, "> ")) ||
-		strchr(tagger_line, '\n') < rb)
-		return error("char" PD_FMT ": malformed tagger",
+		strpbrk(tagger_line, "<>\n") != lb+1 ||
+		strpbrk(lb+2, "><\n ") != rb)
+		return error("char" PD_FMT ": malformed tagger field",
 			tagger_line - buffer);
 
 	/* Check for author name, at least one character, space is acceptable */
@@ -117,25 +121,20 @@ static int verify_tag(char *buffer, unsigned long size)
 		return error("char" PD_FMT ": missing tagger name",
 			tagger_line - buffer);
 
-	/* timestamp */
+	/* timestamp, 1 or more digits followed by space */
 	tagger_line = rb + 2;
-	if (*tagger_line == ' ')
-		return error("char" PD_FMT ": malformed tag timestamp",
+	if (!(len = strspn(tagger_line, "0123456789")))
+		return error("char" PD_FMT ": missing tag timestamp",
 			tagger_line - buffer);
-	for (;;) {
-		unsigned char c = *tagger_line++;
-		if (c == ' ')
-			break;
-		if (isdigit(c))
-			continue;
+	tagger_line += len;
+	if (*tagger_line != ' ')
 		return error("char" PD_FMT ": malformed tag timestamp",
 			tagger_line - buffer);
-	}
+	tagger_line++;
 
 	/* timezone, 5 digits [+-]hhmm, max. 1400 */
 	if (!((tagger_line[0] == '+' || tagger_line[0] == '-') &&
-	      isdigit(tagger_line[1]) && isdigit(tagger_line[2]) &&
-	      isdigit(tagger_line[3]) && isdigit(tagger_line[4]) &&
+	      strspn(tagger_line+1, "0123456789") == 4 &&
 	      tagger_line[5] == '\n' && atoi(tagger_line+1) <= 1400))
 		return error("char" PD_FMT ": malformed tag timezone",
 			tagger_line - buffer);