Skip to content

Align RVV Base64 input validation with the scalar decoder #3662

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
wasphin wants to merge 1 commit into
base: master
Choose a base branch
from
+19 −4
Open

Align RVV Base64 input validation with the scalar decoder #3662

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
11 changes: 7 additions & 4 deletions src/butil/third_party/modp_b64/modp_b64_rvv.cc
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -150,11 +150,14 @@ size_t rvv_modp_b64_decode(char* dest, const char* src, size_t len)
{
if (len == 0) return 0;

/* Strip trailing '=' padding (up to 2 chars for valid base64) */
while (len > 0 && src[len-1] == '=') {
len--;
/* Match the padded scalar decoder's length and padding rules. */
if (len < 4 || len % 4 != 0) return MODP_B64_RVV_ERROR;
if (src[len-1] == '=') {
--len;
if (src[len-1] == '=') {
--len;
}
}
if (len == 0) return 0;

size_t i = 0;
uint8_t* p = (uint8_t*)dest;
Expand Down
12 changes: 12 additions & 0 deletions test/base64_unittest.cc
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -24,4 +24,16 @@ TEST(Base64Test, Basic) {
EXPECT_EQ(kText, decoded);
}

TEST(Base64Test, RejectsMalformedPaddingAndLengths) {
for (const char* input : {"A", "AA", "AAA", "AAAAA", "=", "====",
"A===", "AA======", "AA=A", "AA==AAAA"}) {
std::string decoded;
EXPECT_FALSE(butil::Base64Decode(input, &decoded)) << input;
}
for (const char* input : {"", "AA==", "AAA=", "AAAA"}) {
std::string decoded;
EXPECT_TRUE(butil::Base64Decode(input, &decoded)) << input;
}
}

} // namespace butil
Loading