- char buf2[64];
- int i;
- MDstruct MD;
-
- MDbegin(&MD);
- for(i = 0; i + 64 <= len; i += 64) {
- bcopy(buf+i,buf2,64);
- MDupdate(&MD, buf2, 512);
- }
- bcopy(buf+i,buf2,len-i);
- MDupdate(&MD, buf2, (len-i)*8);
- SIVAL(sum,0,MD.buffer[0]);
- SIVAL(sum,4,MD.buffer[1]);
- SIVAL(sum,8,MD.buffer[2]);
- SIVAL(sum,12,MD.buffer[3]);
+ int i;
+ static char *buf1;
+ static int len1;
+ struct mdfour m;
+
+ if (len > len1) {
+ if (buf1) free(buf1);
+ buf1 = new_array(char, len+4);
+ len1 = len;
+ if (!buf1) out_of_memory("get_checksum2");
+ }
+
+ mdfour_begin(&m);
+
+ memcpy(buf1,buf,len);
+ if (checksum_seed) {
+ SIVAL(buf1,len,checksum_seed);
+ len += 4;
+ }
+
+ for(i = 0; i + CSUM_CHUNK <= len; i += CSUM_CHUNK) {
+ mdfour_update(&m, (uchar *)(buf1+i), CSUM_CHUNK);
+ }
+ /*
+ * Prior to version 27 an incorrect MD4 checksum was computed
+ * by failing to call mdfour_tail() for block sizes that
+ * are multiples of 64. This is fixed by calling mdfour_update()
+ * even when there are no more bytes.
+ */
+ if (len - i > 0 || protocol_version >= 27) {
+ mdfour_update(&m, (uchar *)(buf1+i), (len-i));
+ }
+
+ mdfour_result(&m, (uchar *)sum);
+}
+
+
+void file_checksum(char *fname,char *sum,OFF_T size)
+{
+ OFF_T i;
+ struct map_struct *buf;
+ int fd;
+ OFF_T len = size;
+ char tmpchunk[CSUM_CHUNK];
+ struct mdfour m;
+
+ memset(sum,0,MD4_SUM_LENGTH);
+
+ fd = do_open(fname, O_RDONLY, 0);
+ if (fd == -1) return;
+
+ buf = map_file(fd,size);
+
+ mdfour_begin(&m);
+
+ for(i = 0; i + CSUM_CHUNK <= len; i += CSUM_CHUNK) {
+ memcpy(tmpchunk, map_ptr(buf,i,CSUM_CHUNK), CSUM_CHUNK);
+ mdfour_update(&m, (uchar *)tmpchunk, CSUM_CHUNK);
+ }
+
+ /*
+ * Prior to version 27 an incorrect MD4 checksum was computed
+ * by failing to call mdfour_tail() for block sizes that
+ * are multiples of 64. This is fixed by calling mdfour_update()
+ * even when there are no more bytes.
+ */
+ if (len - i > 0) {
+ memcpy(tmpchunk, map_ptr(buf,i,len-i), len-i);
+ }
+ if (len - i > 0 || protocol_version >= 27) {
+ mdfour_update(&m, (uchar *)tmpchunk, (len-i));
+ }
+
+ mdfour_result(&m, (uchar *)sum);
+
+ close(fd);
+ unmap_file(buf);
+}
+
+
+static int sumresidue;
+static char sumrbuf[CSUM_CHUNK];
+static struct mdfour md;
+
+void sum_init(void)
+{
+ char s[4];
+ mdfour_begin(&md);
+ sumresidue=0;
+ SIVAL(s,0,checksum_seed);
+ sum_update(s,4);
+}
+
+/**
+ * Feed data into an MD4 accumulator, md. The results may be
+ * retrieved using sum_end(). md is used for different purposes at
+ * different points during execution.
+ *
+ * @todo Perhaps get rid of md and just pass in the address each time.
+ * Very slightly clearer and slower.
+ **/
+void sum_update(char *p, int len)
+{
+ int i;
+ if (len + sumresidue < CSUM_CHUNK) {
+ memcpy(sumrbuf+sumresidue, p, len);
+ sumresidue += len;
+ return;
+ }
+
+ if (sumresidue) {
+ i = MIN(CSUM_CHUNK-sumresidue,len);
+ memcpy(sumrbuf+sumresidue,p,i);
+ mdfour_update(&md, (uchar *)sumrbuf, (i+sumresidue));
+ len -= i;
+ p += i;
+ }
+
+ for(i = 0; i + CSUM_CHUNK <= len; i += CSUM_CHUNK) {
+ memcpy(sumrbuf,p+i,CSUM_CHUNK);
+ mdfour_update(&md, (uchar *)sumrbuf, CSUM_CHUNK);
+ }
+
+ if (len - i > 0) {
+ sumresidue = len-i;
+ memcpy(sumrbuf,p+i,sumresidue);
+ } else {
+ sumresidue = 0;
+ }