diff mbox series

[2/3] ascii_to_bin: rework interface to accept destination length

Message ID 20200529065831.9062-2-sde@unmatched.eu
State Accepted
Headers show
Series [1/3] ascii_to_bin: rename arguments to clarify function | expand

Commit Message

Stijn Devriendt May 29, 2020, 6:58 a.m. UTC 
This also shows that the ivt buffer in copyfile was incorrectly sized.

Signed-off-by: Stijn Devriendt <sde@unmatched.eu>
---
 core/cpio_utils.c |  4 ++--
 core/util.c       | 23 +++++++++++++----------
 include/util.h    |  2 +-
 3 files changed, 16 insertions(+), 13 deletions(-)
diff mbox series

Patch

diff --git a/core/cpio_utils.c b/core/cpio_utils.c
index da84057..9afb699 100644
--- a/core/cpio_utils.c
+++ b/core/cpio_utils.c
@@ -389,7 +389,7 @@  int copyfile(int fdin, void *out, unsigned int nbytes, unsigned long *offs, unsi
 	unsigned int md_len = 0;
 	unsigned char *aes_key = NULL;
 	unsigned char *ivt = NULL;
-	unsigned char ivtbuf[32];
+	unsigned char ivtbuf[16];
 
 	struct InputState input_state = {
 		.fdin = fdin,
@@ -449,7 +449,7 @@  int copyfile(int fdin, void *out, unsigned int nbytes, unsigned long *offs, unsi
 
 	if (encrypted) {
 		aes_key = get_aes_key();
-		if (imgivt && strlen(imgivt) && !ascii_to_bin(ivtbuf, imgivt, sizeof(ivtbuf))) {
+		if (imgivt && strlen(imgivt) && !ascii_to_bin(ivtbuf, sizeof(ivtbuf), imgivt)) {
 			ivt = ivtbuf;
 		} else
 			ivt = get_aes_ivt();
diff --git a/core/util.c b/core/util.c
index bd7ef6e..88dd8ac 100644
--- a/core/util.c
+++ b/core/util.c
@@ -54,24 +54,27 @@  static char* TMPDIRSCRIPT = NULL;
  * Convert a hash as hexa string into a sequence of bytes
  * hash must be an array of 32 bytes as specified by SHA256
  */
-int ascii_to_bin(unsigned char *dest, const char *src, size_t srclen)
+int ascii_to_bin(unsigned char *dest, size_t dstlen, const char *src)
 {
 	unsigned int i;
 	unsigned int val;
+	size_t srclen;
 
 	if (src == NULL) {
 		return 0;
 	}
 
+	srclen = strlen(src);
+
 	if (srclen % 2)
 		return -EINVAL;
-	if (strlen(src) == srclen) {
-		for (i = 0; i < srclen; i+= 2) {
-			val = from_ascii(&src[i], 2, LG_16);
-			dest[i / 2] = val;
+	if (srclen == 2 * dstlen) {
+		for (i = 0; i < dstlen; i++) {
+			val = from_ascii(&src[i*2], 2, LG_16);
+			dest[i] = val;
 		}
 	} else
-		return -1;
+		return -EINVAL;
 
 	return 0;
 }
@@ -463,7 +466,7 @@  from_ascii (char const *where, size_t digs, unsigned logbase)
 
 int ascii_to_hash(unsigned char *hash, const char *s)
 {
-	return ascii_to_bin(hash, s, 64);
+	return ascii_to_bin(hash, SHA256_HASH_LENGTH, s);
 }
 
 void hash_to_ascii(const unsigned char *hash, char *str)
@@ -572,8 +575,8 @@  int set_aes_key(const char *key, const char *ivt)
 			return -ENOMEM;
 	}
 
-	ret = ascii_to_bin(aes_key->key,  key, sizeof(aes_key->key) * 2) |
-	      ascii_to_bin(aes_key->ivt,  ivt, sizeof(aes_key->ivt) * 2);
+	ret = ascii_to_bin(aes_key->key, sizeof(aes_key->key), key) |
+	      ascii_to_bin(aes_key->ivt, sizeof(aes_key->ivt), ivt);
 
 	if (ret) {
 		return -EINVAL;
@@ -589,7 +592,7 @@  int set_aes_ivt(const char *ivt)
 	if (!aes_key)
 		return -EFAULT;
 
-	ret = ascii_to_bin(aes_key->ivt,  ivt, sizeof(aes_key->ivt) * 2);
+	ret = ascii_to_bin(aes_key->ivt, sizeof(aes_key->ivt), ivt);
 
 	if (ret) {
 		return -EINVAL;
diff --git a/include/util.h b/include/util.h
index 68df96a..2f83c8a 100644
--- a/include/util.h
+++ b/include/util.h
@@ -140,7 +140,7 @@  typedef void (*notifier) (RECOVERY_STATUS status, int error, int level, const ch
 uintmax_t
 from_ascii (char const *where, size_t digs, unsigned logbase);
 int ascii_to_hash(unsigned char *hash, const char *s);
-int ascii_to_bin(unsigned char *dest, const char *src, size_t srclen);
+int ascii_to_bin(unsigned char *dest, size_t dstlen, const char *src);
 void hash_to_ascii(const unsigned char *hash, char *s);
 int IsValidHash(const unsigned char *hash);