Track routers by hash of identity key; use hex hash of identity key in place of nickname; accept (and use) hash of identity key in EXTEND cells.

svn:r1994

2 files changed, 62 insertions, 2 deletions

diff --git a/src/common/crypto.c b/src/common/crypto.c
index 17e71487a8..93a4738cff 100644
--- a/src/common/crypto.c
+++ b/src/common/crypto.c
@@ -837,8 +837,8 @@ int crypto_pk_get_digest(crypto_pk_env_t *pk, char *digest_out)
  * space).
  *
  * Fingerprints are computed as the SHA1 digest of the ASN.1 encoding
- * of the public key, converted to hexadecimal, with a space after every
- * four digits.
+ * of the public key, converted to hexadecimal, in upper case, with a
+ * space after every four digits.
  */
 int
 crypto_pk_get_fingerprint(crypto_pk_env_t *pk, char *fp_out)
@@ -1433,6 +1433,62 @@ base32_encode(char *dest, int destlen, const char *src, int srclen)
   return 0;
 }
 
+int base16_encode(char *dest, int destlen, const char *src, int srclen)
+{
+  const char *end;
+  char *cp;
+
+  if (destlen < srclen*2+1)
+    return -1;
+
+  cp = dest;
+  end = src+srclen;
+  while (src<end) {
+    sprintf(cp,"%02X",*(const uint8_t*)src);
+    ++src;
+    cp += 2;
+  }
+  *dest = '\0';
+  return 0;
+}
+
+static const char HEX_DIGITS[] = "0123456789ABCDEFabcdef";
+
+static INLINE int hex_decode_digit(char c)
+{
+  const char *cp;
+  int n;
+  cp = strchr(HEX_DIGITS, c);
+  if (!cp)
+    return -1;
+  n = cp-HEX_DIGITS;
+  if (n<=15)
+    return n; /* digit or uppercase */
+  else
+    return n-6; /* lowercase */
+}
+
+int base16_decode(char *dest, int destlen, const char *src, int srclen)
+{
+  const char *end;
+  int v1,v2;
+  if ((srclen % 2) != 0)
+    return -1;
+  if (destlen < srclen/2)
+    return -1;
+  end = src+srclen;
+  while (src<end) {
+    v1 = hex_decode_digit(*src);
+    v2 = hex_decode_digit(*(src+1));
+    if(v1<0||v2<0)
+      return -1;
+    *(uint8_t*)dest = (v1<<4)|v2;
+    ++dest;
+  }
+  *dest = '\0';
+  return 0;
+}
+
 /*
   Local Variables:
   mode:c
diff --git a/src/common/crypto.h b/src/common/crypto.h
index fa8380075e..09bb50f05a 100644
--- a/src/common/crypto.h
+++ b/src/common/crypto.h
@@ -37,6 +37,8 @@
 /** Length of encoded public key fingerprints, including space; but not
  * including terminating NUL. */
 #define FINGERPRINT_LEN 49
+/** Length of hex encoding of SHA1 digest, not including final NUL. */
+#define HEX_DIGEST_LEN 40
 
 typedef struct crypto_pk_env_t crypto_pk_env_t;
 typedef struct crypto_cipher_env_t crypto_cipher_env_t;
@@ -91,6 +93,8 @@ int base64_encode(char *dest, int destlen, const char *src, int srclen);
 int base64_decode(char *dest, int destlen, const char *src, int srclen);
 #define BASE32_CHARS "abcdefghijklmnopqrstuvwxyz234567"
 int base32_encode(char *dest, int destlen, const char *src, int srclen);
+int base16_encode(char *dest, int destlen, const char *src, int srclen);
+int base16_decode(char *dest, int destlen, const char *src, int srclen);
 
 /* Key negotiation */
 crypto_dh_env_t *crypto_dh_new();