Fix issues in base64 encoding.

diff --git a/src/libutil/util.c b/src/libutil/util.c
index 8aac96a90e5f3b95170e8d17e718a52ff7a9ec20..90352f28ecf875848e289a63d4974718a9a50ecc 100644 (file)
--- a/src/libutil/util.c
+++ b/src/libutil/util.c
@@ -2315,21 +2315,30 @@ rspamd_decode_base32 (const gchar *in, gsize inlen, gsize *outlen)
        return res;
 }
 
+
 gchar *
 rspamd_encode_base64 (const guchar *in, gsize inlen, gint str_len, gsize *outlen)
 {
+#define CHECK_SPLIT \
+       do { if (str_len > 0 && cols >= str_len) { \
+                               *o++ = '\r'; \
+                               *o++ = '\n'; \
+                               cols = 0; \
+       } } \
+while (0)
+
        gsize allocated_len = (inlen / 3) * 4 + 4;
        gchar *out, *o;
        guint64 n;
-       guint32 t1, t2, t3;
+       guint32 rem, t, carry;
        gint cols, shift;
-       guint i = 0;
        static const char b64_enc[] =
                "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
                "abcdefghijklmnopqrstuvwxyz"
                "0123456789+/";
 
        if (str_len > 0) {
+               g_assert (str_len > 8);
                allocated_len += (allocated_len / str_len + 1) * 2 + 1;
        }
 
@@ -2376,101 +2385,70 @@ rspamd_encode_base64 (const guchar *in, gsize inlen, gint str_len, gsize *outlen
                inlen -= 6;
        }
 
-       if (str_len > 0 && cols >= str_len) {
-               *o++ = '\r';
-               *o++ = '\n';
-               cols = 0;
-       }
-       /* Trailing bytes */
-       if (inlen > 2) {
-               for (i = 0; i < inlen - 2; i += 3) {
-                       t1 = in[i]; t2 = in[i+1]; t3 = in[i+2];
-                       *o++ = b64_enc[t1];
-                       if (str_len > 0 && ++cols >= str_len) {
-                               *o++ = '\r';
-                               *o++ = '\n';
-                               cols = 0;
-                       }
-                       *o++ = b64_enc[((t1 & 0x03) << 4) | ((t2 >> 4) & 0x0F)];
-                       if (str_len > 0 && ++cols >= str_len) {
-                               *o++ = '\r';
-                               *o++ = '\n';
-                               cols = 0;
+       CHECK_SPLIT;
+
+       rem = 0;
+       carry = 0;
+
+       for (;;) {
+               /* Padding + remaining data (0 - 2 bytes) */
+               switch (rem) {
+               case 0:
+                       if (inlen-- == 0) {
+                               goto end;
                        }
-                       *o++ = b64_enc[((t2 & 0x0F) << 2) | ((t3 >> 6) & 0x03)];
-                       if (str_len > 0 && ++cols >= str_len) {
-                               *o++ = '\r';
-                               *o++ = '\n';
-                               cols = 0;
+                       t = *in++;
+                       *o++ = b64_enc[t >> 2];
+                       carry = (t << 4) & 0x30;
+                       rem = 1;
+                       cols ++;
+               case 1:
+                       if (inlen-- == 0) {
+                               goto end;
                        }
-                       *o++ = b64_enc[t3];
-                       if (str_len > 0 && ++cols >= str_len) {
-                               *o++ = '\r';
-                               *o++ = '\n';
-                               cols = 0;
+                       CHECK_SPLIT;
+                       t = *in++;
+                       *o++ = b64_enc[carry | (t >> 4)];
+                       carry = (t << 2) & 0x3C;
+                       rem = 2;
+                       cols ++;
+               default:
+                       if (inlen-- == 0) {
+                               goto end;
                        }
+                       CHECK_SPLIT;
+                       t = *in ++;
+                       *o++ = b64_enc[carry | (t >> 6)];
+                       cols ++;
+                       CHECK_SPLIT;
+                       *o++ = b64_enc[t & 0x3F];
+                       cols ++;
+                       CHECK_SPLIT;
+                       rem = 0;
                }
        }
 
-       /* Padding + remaining data (0 - 2 bytes) */
-       switch (inlen - i) {
-       case 0:
-               break;
-       case 1:
-               t1 = in[i];
-               *o++ = b64_enc[t1];
-               if (str_len > 0 && ++cols >= str_len) {
-                       *o++ = '\r';
-                       *o++ = '\n';
-                       cols = 0;
-               }
-               *o++ = b64_enc[(t1 & 0x03) << 4];
-               if (str_len > 0 && ++cols >= str_len) {
-                       *o++ = '\r';
-                       *o++ = '\n';
-                       cols = 0;
-               }
+end:
+       if (rem == 1) {
+               *o++ = b64_enc[carry];
+               cols ++;
+               CHECK_SPLIT;
                *o++ = '=';
-               if (str_len > 0 && ++cols >= str_len) {
-                       *o++ = '\r';
-                       *o++ = '\n';
-                       cols = 0;
-               }
+               cols ++;
+               CHECK_SPLIT;
                *o++ = '=';
-               if (str_len > 0 && ++cols >= str_len) {
-                       *o++ = '\r';
-                       *o++ = '\n';
-                       cols = 0;
-               }
-               break;
-       default: /* case 2 */
-               t1 = in[i]; t2 = in[i+1];
-               *o++ = b64_enc[t1];
-               if (str_len > 0 && ++cols >= str_len) {
-                       *o++ = '\r';
-                       *o++ = '\n';
-                       cols = 0;
-               }
-               *o++ = b64_enc[((t1 & 0x03) << 4) | ((t2 >> 4) & 0x0F)];
-               if (str_len > 0 && ++cols >= str_len) {
-                       *o++ = '\r';
-                       *o++ = '\n';
-                       cols = 0;
-               }
-               *o++ = b64_enc[(t2 & 0x0F) << 2];
-               if (str_len > 0 && ++cols >= str_len) {
-                       *o++ = '\r';
-                       *o++ = '\n';
-                       cols = 0;
-               }
+               cols ++;
+               CHECK_SPLIT;
+       }
+       else if (rem == 2) {
+               *o++ = b64_enc[carry];
+               cols ++;
+               CHECK_SPLIT;
                *o++ = '=';
+               cols ++;
        }
 
-       if (str_len > 0 && ++cols >= str_len) {
-               *o++ = '\r';
-               *o++ = '\n';
-               cols = 0;
-       }
+       CHECK_SPLIT;
 
        *o = '\0';