1c977008e

Denys Vlasenko

2025-07-06

SOURCE BUG Duration: 112s

Subject

libbb/yescrypt: code shrink in parameter decoding

SOURCE BUG

This commit was genuinely broken at the time (not related to our build system): libbb/yescrypt eklenirken (2025-07-06 - 2025-07-07 arasi) once unutulan kaynak dosyalari (pw_encrypt_yes.c, hash_sha256_block.c, pw_ascii64.c), ardindan 64-bit'te derlenmeyen bir 'buflen' degiskeni (alg-yescrypt-kdf.c) vardi - busybox'in kendi kodundaki gercek hatalar (e5d3a8763 ile duzeltildi)

→ Bu hatanin tam hikayesini ve duzeltme diffini gor

Binary

No binary (build failed)

Architecture & Compiler Flags

Architecture: x86_64-linux-gnu Compiler: gcc (Ubuntu 11.4.0-1ubuntu1~22.04.3) 11.4.0

—

Build Log

(log yok)

Commit Diff GitHub →

libbb/yescrypt/alg-yescrypt-common.c +17 -31

libbb/yescrypt/alg-yescrypt-common.c+17 -31

@@ -41,33 +41,36 @@ static NOINLINE uint32_t atoi64(uint8_t src)

	static NOINLINE const uint8_t *decode64_uint32(
	uint32_t *dst,
-	const uint8_t *src, uint32_t min)
+	const uint8_t *src, uint32_t val)
	{
	uint32_t start = 0, end = 47, chars = 1, bits = 0;
	uint32_t c;

+	if (!src) /* prevous decode failed already? */
+	goto fail;
+
	c = atoi64(*src++);
	if (c > 63)
	goto fail;

-	*dst = min;
	while (c > end) {
-	*dst += (end + 1 - start) << bits;
+	val += (end + 1 - start) << bits;
	start = end + 1;
	end = start + (62 - end) / 2;
	chars++;
	bits += 6;
	}

-	*dst += (c - start) << bits;
+	val += (c - start) << bits;

	while (--chars) {
	c = atoi64(*src++);
	if (c > 63)
	goto fail;
	bits -= 6;
-	*dst += c << bits;
+	val += c << bits;
	}
+	*dst = val;

	return src;

@@ -192,8 +195,8 @@ uint8_t *yescrypt_r(
	src = setting + 3;

	src = decode64_uint32(&flavor, src, 0);
-	if (!src)
-	return NULL;
+	//if (!src)
+	// return NULL;

	if (flavor < YESCRYPT_RW) {
	params.flags = flavor;
@@ -204,48 +207,32 @@ uint8_t *yescrypt_r(
	}

	src = decode64_uint32(&N_log2, src, 1);
-	if (!src \|\| N_log2 > 63)
+	if (/!src \|\|/ N_log2 > 63)
	return NULL;
	params.N = (uint64_t)1 << N_log2;

	src = decode64_uint32(&params.r, src, 1);
	if (!src)
	return NULL;
-
	if (*src != '$') {
	uint32_t have;
-
	src = decode64_uint32(&have, src, 1);
-	if (!src)
-	return NULL;
-
-	if (have & 1) {
+	if (have & 1)
	src = decode64_uint32(&params.p, src, 2);
-	if (!src)
-	return NULL;
-	}
-
-	if (have & 2) {
+	if (have & 2)
	src = decode64_uint32(&params.t, src, 1);
-	if (!src)
-	return NULL;
-	}
-
-	if (have & 4) {
+	if (have & 4)
	src = decode64_uint32(&params.g, src, 1);
-	if (!src)
-	return NULL;
-	}
-
	if (have & 8) {
	uint32_t NROM_log2;
	src = decode64_uint32(&NROM_log2, src, 1);
-	if (!src \|\| NROM_log2 > 63)
+	if (/!src \|\|/ NROM_log2 > 63)
	return NULL;
	params.NROM = (uint64_t)1 << NROM_log2;
	}
	}
-
+	if (!src)
+	return NULL;
	if (*src++ != '$')
	return NULL;

@@ -274,7 +261,6 @@ uint8_t *yescrypt_r(

	dst = mempcpy(buf, setting, prefixlen + saltstrlen);
	*dst++ = '$';
-
	dst = encode64(dst, buflen - (dst - buf), hashbin, sizeof(hashbin));
	explicit_bzero(hashbin, sizeof(hashbin));
	if (!dst \|\| dst >= buf + buflen)