/*
This file is part of GNUnet.
- (C) 2001, 2002, 2003, 2004, 2005, 2006, 2009 Christian Grothoff (and other contributing authors)
+ (C) 2001, 2002, 2003, 2004, 2005, 2006, 2009, 2012 Christian Grothoff (and other contributing authors)
GNUnet is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published
#include "gnunet_common.h"
#include "gnunet_crypto_lib.h"
#include "gnunet_disk_lib.h"
+#include "gnunet_strings_lib.h"
#include <gcrypt.h>
#define LOG(kind,...) GNUNET_log_from (kind, "util", __VA_ARGS__)
}
+/**
+ * Compute short (256-bit) hash of a given block.
+ *
+ * @param block the data to GNUNET_CRYPTO_hash, length is given as a second argument
+ * @param size the length of the data to GNUNET_CRYPTO_hash
+ * @param ret pointer to where to write the hashcode
+ */
+void
+GNUNET_CRYPTO_short_hash (const void *block, size_t size,
+ struct GNUNET_CRYPTO_ShortHashCode * ret)
+{
+ gcry_md_hash_buffer (GCRY_MD_SHA256, ret, block, size);
+}
+
+
/**
* Context used when hashing a file.
*/
return NULL;
}
fhc->bsize = blocksize;
- if (GNUNET_OK != GNUNET_DISK_file_size (filename, &fhc->fsize, GNUNET_NO))
+ if (GNUNET_OK != GNUNET_DISK_file_size (filename, &fhc->fsize, GNUNET_NO, GNUNET_YES))
{
GNUNET_free (fhc->filename);
GNUNET_free (fhc);
}
-
/* ***************** binary-ASCII encoding *************** */
-/**
- * Get the numeric value corresponding to a character.
- *
- * @param a a character
- * @return corresponding numeric value
- */
-static unsigned int
-getValue__ (unsigned char a)
-{
- if ((a >= '0') && (a <= '9'))
- return a - '0';
- if ((a >= 'A') && (a <= 'V'))
- return (a - 'A' + 10);
- return -1;
-}
-
/**
* Convert GNUNET_CRYPTO_hash to ASCII encoding. The ASCII encoding is rather
GNUNET_CRYPTO_hash_to_enc (const GNUNET_HashCode * block,
struct GNUNET_CRYPTO_HashAsciiEncoded *result)
{
- /**
- * 32 characters for encoding (GNUNET_CRYPTO_hash => 32 characters)
- */
- static char *encTable__ = "0123456789ABCDEFGHIJKLMNOPQRSTUV";
- unsigned int wpos;
- unsigned int rpos;
- unsigned int bits;
- unsigned int vbit;
-
- GNUNET_assert (block != NULL);
- GNUNET_assert (result != NULL);
- vbit = 0;
- wpos = 0;
- rpos = 0;
- bits = 0;
- while ((rpos < sizeof (GNUNET_HashCode)) || (vbit > 0))
- {
- if ((rpos < sizeof (GNUNET_HashCode)) && (vbit < 5))
- {
- bits = (bits << 8) | ((unsigned char *) block)[rpos++]; /* eat 8 more bits */
- vbit += 8;
- }
- if (vbit < 5)
- {
- bits <<= (5 - vbit); /* zero-padding */
- GNUNET_assert (vbit == 2); /* padding by 3: 512+3 mod 5 == 0 */
- vbit = 5;
- }
- GNUNET_assert (wpos < sizeof (struct GNUNET_CRYPTO_HashAsciiEncoded) - 1);
- result->encoding[wpos++] = encTable__[(bits >> (vbit - 5)) & 31];
- vbit -= 5;
- }
- GNUNET_assert (wpos == sizeof (struct GNUNET_CRYPTO_HashAsciiEncoded) - 1);
- GNUNET_assert (vbit == 0);
- result->encoding[wpos] = '\0';
+ char *np;
+
+ np = GNUNET_STRINGS_data_to_string ((const unsigned char *) block,
+ sizeof (struct GNUNET_HashCode),
+ (char*) result,
+ sizeof (struct GNUNET_CRYPTO_HashAsciiEncoded) - 1);
+ GNUNET_assert (NULL != np);
+ *np = '\0';
}
/**
- * Convert ASCII encoding back to GNUNET_CRYPTO_hash
+ * Convert ASCII encoding back to hash code.
*
* @param enc the encoding
- * @param result where to store the GNUNET_CRYPTO_hash code
+ * @param enclen number of characters in 'enc' (without 0-terminator, which can be missing)
+ * @param result where to store the hash code
* @return GNUNET_OK on success, GNUNET_SYSERR if result has the wrong encoding
*/
int
GNUNET_CRYPTO_hash_from_string2 (const char *enc, size_t enclen,
GNUNET_HashCode * result)
{
- unsigned int rpos;
- unsigned int wpos;
- unsigned int bits;
- unsigned int vbit;
- int ret;
+ char upper_enc[enclen];
+ char* up_ptr = upper_enc;
- if (enclen != sizeof (struct GNUNET_CRYPTO_HashAsciiEncoded) - 1)
- return GNUNET_SYSERR;
+ GNUNET_STRINGS_utf8_toupper(enc, &up_ptr);
- vbit = 2; /* padding! */
- wpos = sizeof (GNUNET_HashCode);
- rpos = sizeof (struct GNUNET_CRYPTO_HashAsciiEncoded) - 1;
- bits = (ret = getValue__ (enc[--rpos])) >> 3;
- if (-1 == ret)
- return GNUNET_SYSERR;
- while (wpos > 0)
- {
- GNUNET_assert (rpos > 0);
- bits = ((ret = getValue__ (enc[--rpos])) << vbit) | bits;
- if (-1 == ret)
- return GNUNET_SYSERR;
- vbit += 5;
- if (vbit >= 8)
- {
- ((unsigned char *) result)[--wpos] = (unsigned char) bits;
- bits >>= 8;
- vbit -= 8;
- }
- }
- GNUNET_assert (rpos == 0);
- GNUNET_assert (vbit == 0);
- return GNUNET_OK;
+ return GNUNET_STRINGS_string_to_data (upper_enc, enclen,
+ (unsigned char*) result,
+ sizeof (struct GNUNET_HashCode));
}
}
+
+/**
+ * Double short (256-bit) hash to create a long hash.
+ *
+ * @param sh short hash to double
+ * @param dh where to store the (doubled) long hash (not really a hash)
+ */
+void
+GNUNET_CRYPTO_short_hash_double (const struct GNUNET_CRYPTO_ShortHashCode *sh,
+ struct GNUNET_HashCode *dh)
+{
+ char *ptr;
+
+ ptr = (char*) dh;
+ memcpy (ptr, sh, sizeof (struct GNUNET_CRYPTO_ShortHashCode));
+ memcpy (&ptr[sizeof (struct GNUNET_CRYPTO_ShortHashCode)], sh, sizeof (struct GNUNET_CRYPTO_ShortHashCode));
+}
+
+
+/**
+ * Truncate doubled short hash back to a short hash.
+ *
+ * @param dh doubled short hash to reduce again
+ * @param sh where to store the short hash
+ * @return GNUNET_OK on success, GNUNET_SYSERR if this was not a
+ * doubled short hash
+ */
+int
+GNUNET_CRYPTO_short_hash_from_truncation (const struct GNUNET_HashCode *dh,
+ struct GNUNET_CRYPTO_ShortHashCode *sh)
+{
+ const struct GNUNET_CRYPTO_ShortHashCode *s;
+
+ s = (const struct GNUNET_CRYPTO_ShortHashCode *) dh;
+ if (0 != memcmp (&s[0],
+ &s[1],
+ sizeof (struct GNUNET_CRYPTO_ShortHashCode)))
+ return GNUNET_SYSERR;
+ *sh = *s;
+ return GNUNET_OK;
+}
+
+
+/**
+ * Convert ASCII encoding back to a 'struct GNUNET_CRYPTO_ShortHash'
+ *
+ * @param enc the encoding
+ * @param enclen number of characters in 'enc' (without 0-terminator, which can be missing)
+ * @param result where to store the GNUNET_CRYPTO_hash code
+ * @return GNUNET_OK on success, GNUNET_SYSERR if result has the wrong encoding
+ */
+int
+GNUNET_CRYPTO_short_hash_from_string2 (const char *enc, size_t enclen,
+ struct GNUNET_CRYPTO_ShortHashCode * result)
+{
+
+ char upper_enc[enclen];
+ char* up_ptr = upper_enc;
+
+ GNUNET_STRINGS_utf8_toupper(enc, &up_ptr);
+ return GNUNET_STRINGS_string_to_data (upper_enc, enclen,
+ (unsigned char*) result,
+ sizeof (struct GNUNET_CRYPTO_ShortHashCode));
+}
+
+
+/**
+ * Convert short hash to ASCII encoding.
+ *
+ * @param block the hash code
+ * @param result where to store the encoding (struct GNUNET_CRYPTO_ShortHashAsciiEncoded can be
+ * safely cast to char*, a '\\0' termination is set).
+ */
+void
+GNUNET_CRYPTO_short_hash_to_enc (const struct GNUNET_CRYPTO_ShortHashCode * block,
+ struct GNUNET_CRYPTO_ShortHashAsciiEncoded *result)
+{
+ char *np;
+
+ np = GNUNET_STRINGS_data_to_string ((const unsigned char *) block,
+ sizeof (struct GNUNET_CRYPTO_ShortHashCode),
+ (char*) result,
+ sizeof (struct GNUNET_CRYPTO_ShortHashAsciiEncoded) - 1);
+ GNUNET_assert (NULL != np);
+ *np = '\0';
+}
+
+/**
+ * Compare function for ShortHashCodes, producing a total ordering
+ * of all hashcodes.
+ *
+ * @param h1 some hash code
+ * @param h2 some hash code
+ * @return 1 if h1 > h2, -1 if h1 < h2 and 0 if h1 == h2.
+ */
+int
+GNUNET_CRYPTO_short_hash_cmp (const struct GNUNET_CRYPTO_ShortHashCode * h1,
+ const struct GNUNET_CRYPTO_ShortHashCode * h2)
+{
+ unsigned int *i1;
+ unsigned int *i2;
+ int i;
+
+ i1 = (unsigned int *) h1;
+ i2 = (unsigned int *) h2;
+ for (i = (sizeof (struct GNUNET_CRYPTO_ShortHashCode) / sizeof (unsigned int)) - 1; i >= 0; i--)
+ {
+ if (i1[i] > i2[i])
+ return 1;
+ if (i1[i] < i2[i])
+ return -1;
+ }
+ return 0;
+}
+
/* end of crypto_hash.c */
projects / oweals / gnunet.git / blobdiff