* Addition of support for SHA1 to SHA512 needed for future additions to

     Alpine. The code is taken and adapted from code in RFC 4634.

1 files changed, 65 insertions, 0 deletions

diff --git a/imap/src/c-client/sha.c b/imap/src/c-client/sha.c
new file mode 100644
index 00000000..3c4b43c3
--- /dev/null
+++ b/imap/src/c-client/sha.c
@@ -0,0 +1,65 @@
+/*
+ * Copyright 2021 Eduardo Chappa
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ */
+/* This algorithm is taken from the code in RFC 4634 */
+
+#include "c-client.h"
+#include "sha.h"
+#include "hmac.c"
+#include "sha1.c"
+#include "usha.c"
+#include "sha224-256.c"
+#include "sha384-512.c"
+
+struct hash {
+    char *name;
+    SHAversion whichSha;
+    int hashsize;
+} hashes[] = {
+  {"SHA1", CCSHA1, SHA1HashSize},
+  {"SHA224", CCSHA224, SHA224HashSize},
+  {"SHA256", CCSHA256, SHA256HashSize},
+  {"SHA384", CCSHA384, SHA384HashSize},
+  {"SHA512", CCSHA512, SHA512HashSize},
+  {NIL, CCSHA512, SHA512HashSize}
+};
+static const char hexdigits[] = "0123456789abcdef";
+
+char *hash_from_sizedtext(char *hash, char *text, size_t len)
+{
+  char *rv = NIL;
+  USHAContext sha;
+  HMACContext hmac;
+  uint8_t Message_Digest[USHAMaxHashSize];
+  int i, hashno;
+
+  if(!hash || !text) return NIL;
+
+  for(hashno = 0; hashes[hashno].name != NIL; hashno++)
+     if(!compare_cstring(hashes[hashno].name, hash))
+	break;
+
+  if(hashno >= 0 && hashno <= USHAMaxHashSize && hashes[hashno].name){
+     memset(&sha, '\343', sizeof(USHAContext));
+     memset(&hmac, '\343', sizeof(HMACContext));
+     if(USHAReset(&sha, hashes[hashno].whichSha) == shaSuccess
+	&& USHAInput(&sha, (const uint8_t *) text, len) == shaSuccess){
+	if(USHAResult(&sha, (uint8_t *) Message_Digest) == shaSuccess){
+	   rv = fs_get(2*hashes[hashno].hashsize + 1);
+	   for (i = 0; i < hashes[hashno].hashsize ; ++i) {
+	      rv[2*i]   = hexdigits[(Message_Digest[i] >> 4) & 0xF];
+	      rv[2*i+1] = hexdigits[Message_Digest[i] & 0xF];
+	   }
+	   rv[2*i] = '\0';
+	}
+     }
+  }
+  return rv;
+}