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[PATCH v3 22/22] add_ref(): verify that the refname is formatted correctly

From
Michael Haggerty <mhagger@alum.mit.edu>
Date
Sep 15, 2011, 21:10 UTC
Message-ID
<1316121043-29367-23-git-send-email-mhagger@alum.mit.edu>
In-Reply-To
<1316121043-29367-1-git-send-email-mhagger@alum.mit.edu>

In add_ref(), verify that the refname is formatted correctly before adding it to the ref_list. Here we have to allow refname components that start with ".", since (for example) the remote protocol uses synthetic reference name ".have". So add a new REFNAME_DOT_COMPONENT flag that can be passed to check_refname_format() to allow leading dots.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
---
 refs.c |   18 ++++++++++++++----
 refs.h |    6 +++++-
 2 files changed, 19 insertions(+), 5 deletions(-)
diff --git a/refs.c b/refs.c
index 096b42c..832a52f 100644
--- a/refs.c
+++ b/refs.c
@@ -56,6 +56,8 @@ static struct ref_list *add_ref(const char *name, const unsigned char *sha1,
 	entry = xmalloc(sizeof(struct ref_list) + len);
 	hashcpy(entry->sha1, sha1);
 	hashclr(entry->peeled);
+	if (check_refname_format(name, REFNAME_ALLOW_ONELEVEL|REFNAME_DOT_COMPONENT))
+		die("Reference has invalid format: '%s'", name);
 	memcpy(entry->name, name, len);
 	entry->flag = flag;
 	entry->next = list;
@@ -900,7 +902,7 @@ static inline int bad_ref_char(int ch)
  * the length of the component found, or -1 if the component is not
  * legal.
  */
-static int check_refname_component(const char *ref)
+static int check_refname_component(const char *ref, int flags)
 {
 	const char *cp;
 	char last = '\0';
@@ -919,8 +921,16 @@ static int check_refname_component(const char *ref)
 	}
 	if (cp == ref)
 		return -1; /* Component has zero length. */
-	if (ref[0] == '.')
-		return -1; /* Component starts with '.'. */
+	if (ref[0] == '.') {
+		if (!(flags & REFNAME_DOT_COMPONENT))
+			return -1; /* Component starts with '.'. */
+		/*
+		 * Even if leading dots are allowed, don't allow "."
+		 * as a component (".." is prevented by a rule above).
+		 */
+		if (ref[1] == '\0')
+			return -1; /* Component equals ".". */
+	}
 	if (cp - ref >= 5 && !memcmp(cp - 5, ".lock", 5))
 		return -1; /* Refname ends with ".lock". */
 	return cp - ref;
@@ -932,7 +942,7 @@ int check_refname_format(const char *ref, int flags)
 
 	while (1) {
 		/* We are at the start of a path component. */
-		component_len = check_refname_component(ref);
+		component_len = check_refname_component(ref, flags);
 		if (component_len < 0) {
 			if ((flags & REFNAME_REFSPEC_PATTERN) &&
 					ref[0] == '*' &&
diff --git a/refs.h b/refs.h
index b0da5fc..d5ac133 100644
--- a/refs.h
+++ b/refs.h
@@ -99,6 +99,7 @@ extern int for_each_reflog(each_ref_fn, void *);
 
 #define REFNAME_ALLOW_ONELEVEL 1
 #define REFNAME_REFSPEC_PATTERN 2
+#define REFNAME_DOT_COMPONENT 4
 
 /*
  * Return 0 iff ref has the correct format for a refname according to
@@ -106,7 +107,10 @@ extern int for_each_reflog(each_ref_fn, void *);
  * REFNAME_ALLOW_ONELEVEL is set in flags, then accept one-level
  * reference names.  If REFNAME_REFSPEC_PATTERN is set in flags, then
  * allow a "*" wildcard character in place of one of the name
- * components.  No leading or repeated slashes are accepted.
+ * components.  No leading or repeated slashes are accepted.  If
+ * REFNAME_DOT_COMPONENT is set in flags, then allow refname
+ * components to start with "." (but not a whole component equal to
+ * "." or "..").
  */
 extern int check_refname_format(const char *ref, int flags);
 

-- 
1.7.6.8.gd2879
Previous: Michael Haggerty
Message 60 of 60 in “Clean up refname checks and normalization”
  1. 00/22 Clean up refname checks and normalizationMichael Haggerty, Sep 15, 2011
  2. 01/22 t1402: add some more testsMichael Haggerty, Sep 15, 2011
  3. 02/22 git check-ref-format: add options --allow-onelevel and --refspec-patternMichael Haggerty, Sep 15, 2011
  4. 03/22 Change bad_ref_char() to return a boolean valueMichael Haggerty, Sep 15, 2011
  5. 04/22 Change check_ref_format() to take a flags argumentMichael Haggerty, Sep 15, 2011
  6. 05/22 Refactor check_refname_format()Michael Haggerty, Sep 15, 2011
  7. 06/22 Do not allow ".lock" at the end of any refname componentMichael Haggerty, Sep 15, 2011
  8. 07/22 Make collapse_slashes() allocate memory for its resultMichael Haggerty, Sep 15, 2011
  9. 08/22 Inline function refname_format_print()Michael Haggerty, Sep 15, 2011
  10. 09/22 Change check_refname_format() to reject unnormalized refnamesMichael Haggerty, Sep 15, 2011
  11. 10/22 resolve_ref(): explicitly fail if a symlink is not readableMichael Haggerty, Sep 15, 2011
  12. 11/22 resolve_ref(): use prefixcmp()Michael Haggerty, Sep 15, 2011
  13. 12/22 resolve_ref(): only follow a symlink that contains a valid, normalized refnameMichael Haggerty, Sep 15, 2011
  14. 13/22 resolve_ref(): turn buffer into a proper string as soon as possibleMichael Haggerty, Sep 15, 2011
  15. Thomas RastSep 23, 2011
  16. Michael HaggertySep 23, 2011
  17. 1/1 get_sha1_hex(): do not read past a NUL characterMichael Haggerty, Sep 23, 2011
  18. Junio C HamanoSep 23, 2011
  19. Thomas RastOct 5, 2011
  20. Junio C HamanoOct 5, 2011
  21. 14/22 resolve_ref(): extract a function get_packed_ref()Michael Haggerty, Sep 15, 2011
  22. 15/22 resolve_ref(): do not follow incorrectly-formatted symbolic refsMichael Haggerty, Sep 15, 2011
  23. 16/22 remote: use xstrdup() instead of strdup()Michael Haggerty, Sep 15, 2011
  24. 17/22 remote: avoid passing NULL to read_ref()Michael Haggerty, Sep 15, 2011
  25. 18/22 resolve_ref(): verify that the input refname has the right formatMichael Haggerty, Sep 15, 2011
  26. 19/22 resolve_ref(): emit warnings for improperly-formatted referencesMichael Haggerty, Sep 15, 2011
  27. Jeff KingOct 11, 2011
  28. Junio C HamanoOct 11, 2011
  29. Junio C HamanoOct 11, 2011
  30. Re* [PATCH v3 19/22] resolve_ref(): emit warnings for improperly-formatted referencesJunio C Hamano, Oct 11, 2011
  31. Jeff KingOct 11, 2011
  32. Junio C HamanoOct 11, 2011
  33. Jeff KingOct 11, 2011
  34. Junio C HamanoOct 12, 2011
  35. Jeff KingOct 11, 2011
  36. Junio C HamanoOct 11, 2011
  37. Jeff KingOct 12, 2011
  38. Junio C HamanoOct 12, 2011
  39. Jeff KingOct 12, 2011
  40. 1/2 refs.c: move dwim_ref()/dwim_log() from sha1_name.cJunio C Hamano, Oct 12, 2011
  41. 2/2 Restrict ref-like names immediately below $GIT_DIRJunio C Hamano, Oct 12, 2011
  42. Michael HaggertyOct 12, 2011
  43. Junio C HamanoOct 12, 2011
  44. Michael HaggertyOct 12, 2011
  45. Junio C HamanoOct 12, 2011
  46. Junio C HamanoOct 19, 2011
  47. Junio C HamanoOct 19, 2011
  48. Michael HaggertyOct 19, 2011
  49. Junio C HamanoOct 19, 2011
  50. Junio C HamanoOct 19, 2011
  51. resolve_ref(): report breakage to the caller without warningJunio C Hamano, Oct 19, 2011
  52. Michael HaggertyOct 19, 2011
  53. Junio C HamanoOct 19, 2011
  54. Jeff KingOct 12, 2011
  55. Michael HaggertyOct 12, 2011
  56. Junio C HamanoOct 12, 2011
  57. Jeff KingOct 12, 2011
  58. 20/22 resolve_ref(): also treat a too-long SHA1 as invalidMichael Haggerty, Sep 15, 2011
  59. 21/22 resolve_ref(): expand documentationMichael Haggerty, Sep 15, 2011
  60. 22/22 add_ref(): verify that the refname is formatted correctlyMichael Haggerty, Sep 15, 2011

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