Dont over-read fd, use function pointer for hash function.

diff --git a/include/libbb.h b/include/libbb.h
index 88f43d01c850ce8a9f47670648cb938316c526a6..22a77e610bbe8ead54b4423af01ada8b4de67028 100644 (file)
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -479,7 +479,7 @@ extern void xregcomp(regex_t *preg, const char *regex, int cflags);
 
 #define HASH_SHA1      1
 #define HASH_MD5       2
-extern int hash_fd(int fd, const off_t size, const uint8_t hash_algo, uint8_t *hashval);
+extern int hash_fd(int fd, const size_t size, const uint8_t hash_algo, uint8_t *hashval);
 
 
 #endif /* __LIBCONFIG_H__ */

diff --git a/libbb/hash_fd.c b/libbb/hash_fd.c
index ad0e4f4460e80020c22294e8f979d61ab71c8006..770ba09c49b658208bb058f619124a1521c6f65d 100644 (file)
--- a/libbb/hash_fd.c
+++ b/libbb/hash_fd.c
@@ -166,10 +166,11 @@ static void sha1_begin(sha1_ctx_t *ctx)
 
 /* SHA1 hash data in an array of bytes into hash buffer and call the        */
 /* hash_compile function as required.                                       */
-static void sha1_hash(const unsigned char data[], unsigned int len, sha1_ctx_t *ctx)
+static void sha1_hash(const void *data, size_t len, void *ctx_v)
 {
-       uint32_t pos = (uint32_t) (ctx->count[0] & SHA1_MASK),
-               freeb = SHA1_BLOCK_SIZE - pos;
+       sha1_ctx_t *ctx = (sha1_ctx_t *) ctx_v;
+       uint32_t pos = (uint32_t) (ctx->count[0] & SHA1_MASK);
+       uint32_t freeb = SHA1_BLOCK_SIZE - pos;
        const unsigned char *sp = data;
 
        if ((ctx->count[0] += len) < len)
@@ -706,6 +707,15 @@ static void md5_hash_bytes(const void *buffer, size_t len, md5_ctx_t *ctx)
        }
 }
 
+static void md5_hash(const void *buffer, size_t length, void *md5_ctx)
+{
+       if (length % 64 == 0) {
+               md5_hash_block(buffer, length, md5_ctx);
+       } else {
+               md5_hash_bytes(buffer, length, md5_ctx);
+       }
+}
+
 /* Process the remaining bytes in the buffer and put result from CTX
  * in first 16 bytes following RESBUF.  The result is always in little
  * endian byte order, so that a byte-wise output yields to the wanted
@@ -760,13 +770,17 @@ static void *md5_end(void *resbuf, md5_ctx_t *ctx)
 
 
 
-extern int hash_fd(int src_fd, const off_t size, const uint8_t hash_algo,
+extern int hash_fd(int src_fd, const size_t size, const uint8_t hash_algo,
                                   uint8_t * hashval)
 {
        int result = EXIT_SUCCESS;
-       off_t hashed_count = 0;
-       unsigned int blocksize = 0;
+//     size_t hashed_count = 0;
+       size_t blocksize = 0;
+       size_t remaining = size;
        unsigned char *buffer = NULL;
+       void (*hash_fn_ptr)(const void *, size_t, void *) = NULL;
+       void *cx = NULL;
+
 #ifdef CONFIG_SHA1SUM
        sha1_ctx_t sha1_cx;
 #endif
@@ -779,13 +793,17 @@ extern int hash_fd(int src_fd, const off_t size, const uint8_t hash_algo,
        if (hash_algo == HASH_SHA1) {
                /* Ensure that BLOCKSIZE is a multiple of 64.  */
                blocksize = 65536;
-               buffer = malloc(blocksize);
+               buffer = xmalloc(blocksize);
+               hash_fn_ptr = sha1_hash;
+               cx = &sha1_cx;
        }
 #endif
 #ifdef CONFIG_MD5SUM
        if (hash_algo == HASH_MD5) {
                blocksize = 4096;
-               buffer = malloc(blocksize + 72);
+               buffer = xmalloc(blocksize + 72);
+               hash_fn_ptr = md5_hash;
+               cx = &md5_cx;
        }
 #endif
        
@@ -801,33 +819,29 @@ extern int hash_fd(int src_fd, const off_t size, const uint8_t hash_algo,
        }
 #endif
        /* Iterate over full file contents.  */
-       do {
-               const ssize_t count = bb_full_read(src_fd, buffer, blocksize);
-
-               if (count < 1) {
+       while ((remaining == (size_t) -1) || (remaining > 0)) {
+               size_t read_try;
+               ssize_t read_got;
+
+               if (remaining > blocksize) {
+                       read_try = blocksize;
+               } else {
+                       read_try = remaining;
+               }
+               read_got = bb_full_read(src_fd, buffer, read_try);
+               if (read_got < 1) {
                        /* count == 0 means short read
                         * count == -1 means read error */
-                       result = count - 1;
+                       result = read_got - 1;
                        break;
                }
-               hashed_count += count;
+               if (remaining != (size_t) -1) {
+                       remaining -= read_got;
+               }
 
                /* Process buffer */
-#ifdef CONFIG_SHA1SUM
-               if (hash_algo == HASH_SHA1) {
-                       sha1_hash(buffer, count, &sha1_cx);
-               }
-#endif
-#ifdef CONFIG_MD5SUM
-               if (hash_algo == HASH_MD5) {
-                       if (count % 64 == 0) {
-                               md5_hash_block(buffer, count, &md5_cx);
-                       } else {
-                               md5_hash_bytes(buffer, count, &md5_cx);
-                       }
-               }
-#endif
-       } while ((size == (off_t) - 1) || (hashed_count < size));
+               hash_fn_ptr(buffer, read_got, cx);
+       }
 
        /* Finalize and write the hash into our buffer.  */
 #ifdef CONFIG_SHA1SUM