Fix undefined casts in sk_*_pop_free and sk_*_deep_copy.
Unfortunately, some projects are calling into sk_pop_free directly, so
we must leave a compatibility version around for now.
Bug: chromium:785442
Change-Id: I1577fce6f23af02114f7e9f7bf2b14e9d22fa9ae
Reviewed-on: https://boringssl-review.googlesource.com/32113
Commit-Queue: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
Reviewed-by: Adam Langley <agl@google.com>
diff --git a/crypto/stack/stack.c b/crypto/stack/stack.c
index 6a23722..fe50bb9 100644
--- a/crypto/stack/stack.c
+++ b/crypto/stack/stack.c
@@ -133,19 +133,31 @@
OPENSSL_free(sk);
}
-void sk_pop_free(_STACK *sk, void (*func)(void *)) {
+void sk_pop_free_ex(_STACK *sk, void (*call_free_func)(stack_free_func, void *),
+ stack_free_func free_func) {
if (sk == NULL) {
return;
}
for (size_t i = 0; i < sk->num; i++) {
if (sk->data[i] != NULL) {
- func(sk->data[i]);
+ call_free_func(free_func, sk->data[i]);
}
}
sk_free(sk);
}
+// Historically, |sk_pop_free| called the function as |stack_free_func|
+// directly. This is undefined in C. Some callers called |sk_pop_free| directly,
+// so we must maintain a compatibility version for now.
+static void call_free_func_legacy(stack_free_func func, void *ptr) {
+ func(ptr);
+}
+
+void sk_pop_free(_STACK *sk, stack_free_func free_func) {
+ sk_pop_free_ex(sk, call_free_func_legacy, free_func);
+}
+
size_t sk_insert(_STACK *sk, void *p, size_t where) {
if (sk == NULL) {
return 0;
@@ -363,8 +375,11 @@
return old;
}
-_STACK *sk_deep_copy(const _STACK *sk, void *(*copy_func)(void *),
- void (*free_func)(void *)) {
+_STACK *sk_deep_copy(const _STACK *sk,
+ void *(*call_copy_func)(stack_copy_func, void *),
+ stack_copy_func copy_func,
+ void (*call_free_func)(stack_free_func, void *),
+ stack_free_func free_func) {
_STACK *ret = sk_dup(sk);
if (ret == NULL) {
return NULL;
@@ -374,11 +389,11 @@
if (ret->data[i] == NULL) {
continue;
}
- ret->data[i] = copy_func(ret->data[i]);
+ ret->data[i] = call_copy_func(copy_func, ret->data[i]);
if (ret->data[i] == NULL) {
for (size_t j = 0; j < i; j++) {
if (ret->data[j] != NULL) {
- free_func(ret->data[j]);
+ call_free_func(free_func, ret->data[j]);
}
}
sk_free(ret);
diff --git a/include/openssl/stack.h b/include/openssl/stack.h
index 7431576..3a7155f 100644
--- a/include/openssl/stack.h
+++ b/include/openssl/stack.h
@@ -86,6 +86,16 @@
// STACK_OF(FOO), the macros would be sk_FOO_new, sk_FOO_pop etc.
+// stack_free_func is a function that frees an element in a stack. Note its
+// actual type is void (*)(T *) for some T. Low-level |sk_*| functions will be
+// passed a type-specific wrapper to call it correctly.
+typedef void (*stack_free_func)(void *ptr);
+
+// stack_copy_func is a function that copies an element in a stack. Note its
+// actual type is T *(*)(T *) for some T. Low-level |sk_*| functions will be
+// passed a type-specific wrapper to call it correctly.
+typedef void *(*stack_copy_func)(void *ptr);
+
// stack_cmp_func is a comparison function that returns a value < 0, 0 or > 0
// if |*a| is less than, equal to or greater than |*b|, respectively. Note the
// extra indirection - the function is given a pointer to a pointer to the
@@ -140,12 +150,17 @@
OPENSSL_EXPORT void *sk_set(_STACK *sk, size_t i, void *p);
// sk_free frees the given stack and array of pointers, but does nothing to
-// free the individual elements. Also see |sk_pop_free|.
+// free the individual elements. Also see |sk_pop_free_ex|.
OPENSSL_EXPORT void sk_free(_STACK *sk);
-// sk_pop_free calls |free_func| on each element in the stack and then frees
-// the stack itself.
-OPENSSL_EXPORT void sk_pop_free(_STACK *sk, void (*free_func)(void *));
+// sk_pop_free_ex calls |free_func| on each element in the stack and then frees
+// the stack itself. Note this corresponds to |sk_FOO_pop_free|. It is named
+// |sk_pop_free_ex| as a workaround for existing code calling an older version
+// of |sk_pop_free|.
+OPENSSL_EXPORT void sk_pop_free_ex(_STACK *sk,
+ void (*call_free_func)(stack_free_func,
+ void *),
+ stack_free_func free_func);
// sk_insert inserts |p| into the stack at index |where|, moving existing
// elements if needed. It returns the length of the new stack, or zero on
@@ -207,9 +222,20 @@
// sk_deep_copy performs a copy of |sk| and of each of the non-NULL elements in
// |sk| by using |copy_func|. If an error occurs, |free_func| is used to free
// any copies already made and NULL is returned.
-OPENSSL_EXPORT _STACK *sk_deep_copy(const _STACK *sk,
- void *(*copy_func)(void *),
- void (*free_func)(void *));
+OPENSSL_EXPORT _STACK *sk_deep_copy(
+ const _STACK *sk, void *(*call_copy_func)(stack_copy_func, void *),
+ stack_copy_func copy_func, void (*call_free_func)(stack_free_func, void *),
+ stack_free_func free_func);
+
+
+// Deprecated functions.
+
+// sk_pop_free behaves like |sk_pop_free_ex| but performs an invalid function
+// pointer cast. It exists because some existing callers called |sk_pop_free|
+// directly.
+//
+// TODO(davidben): Migrate callers to bssl::UniquePtr and remove this.
+OPENSSL_EXPORT void sk_pop_free(_STACK *sk, stack_free_func free_func);
// Defining stack types.
@@ -252,8 +278,20 @@
#define BORINGSSL_DEFINE_STACK_OF_IMPL(name, ptrtype, constptrtype) \
DECLARE_STACK_OF(name) \
\
+ typedef void (*stack_##name##_free_func)(ptrtype); \
+ typedef ptrtype (*stack_##name##_copy_func)(ptrtype); \
typedef int (*stack_##name##_cmp_func)(constptrtype *a, constptrtype *b); \
\
+ static inline OPENSSL_UNUSED void sk_##name##_call_free_func( \
+ stack_free_func free_func, void *ptr) { \
+ ((stack_##name##_free_func)free_func)((ptrtype)ptr); \
+ } \
+ \
+ static inline OPENSSL_UNUSED void *sk_##name##_call_copy_func( \
+ stack_copy_func copy_func, void *ptr) { \
+ return (void *)((stack_##name##_copy_func)copy_func)((ptrtype)ptr); \
+ } \
+ \
static inline OPENSSL_UNUSED STACK_OF(name) * \
sk_##name##_new(stack_##name##_cmp_func comp) { \
return (STACK_OF(name) *)sk_new((stack_cmp_func)comp); \
@@ -287,8 +325,9 @@
} \
\
static inline OPENSSL_UNUSED void sk_##name##_pop_free( \
- STACK_OF(name) *sk, void (*free_func)(ptrtype p)) { \
- sk_pop_free((_STACK *)sk, (void (*)(void *))free_func); \
+ STACK_OF(name) *sk, stack_##name##_free_func free_func) { \
+ sk_pop_free_ex((_STACK *)sk, sk_##name##_call_free_func, \
+ (stack_free_func)free_func); \
} \
\
static inline OPENSSL_UNUSED size_t sk_##name##_insert( \
@@ -349,9 +388,10 @@
sk_##name##_deep_copy(const STACK_OF(name) *sk, \
ptrtype(*copy_func)(ptrtype), \
void (*free_func)(ptrtype)) { \
- return (STACK_OF(name) *)sk_deep_copy((const _STACK *)sk, \
- (void *(*)(void *))copy_func, \
- (void (*)(void *))free_func); \
+ return (STACK_OF(name) *)sk_deep_copy( \
+ (const _STACK *)sk, sk_##name##_call_copy_func, \
+ (stack_copy_func)copy_func, sk_##name##_call_free_func, \
+ (stack_free_func)free_func); \
}
// DEFINE_NAMED_STACK_OF defines |STACK_OF(name)| to be a stack whose elements
@@ -410,10 +450,14 @@
struct DeleterImpl<
Stack, typename std::enable_if<!StackTraits<Stack>::kIsConst>::type> {
static void Free(Stack *sk) {
- sk_pop_free(
- reinterpret_cast<_STACK *>(sk),
- reinterpret_cast<void (*)(void *)>(
- DeleterImpl<typename StackTraits<Stack>::Type>::Free));
+ // sk_FOO_pop_free is defined by macros and bound by name, so we cannot
+ // access it from C++ here.
+ using Type = typename StackTraits<Stack>::Type;
+ sk_pop_free_ex(reinterpret_cast<_STACK *>(sk),
+ [](stack_free_func unused, void *ptr) {
+ DeleterImpl<Type>::Free(reinterpret_cast<Type *>(ptr));
+ },
+ nullptr);
}
};