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authorMatt Johnston <matt@ucc.asn.au>2007-01-11 03:14:55 +0000
committerMatt Johnston <matt@ucc.asn.au>2007-01-11 03:14:55 +0000
commit9d5ed350a749368c84254c11e7616ce3c891193a (patch)
tree6dacbff2e9f5c60a1568382db55c72dd6d2ce925 /libtomcrypt/src/misc/pkcs5/pkcs_5_2.c
parentca52f070aecf91e75f6ae6c87d4ae1a2189ccb14 (diff)
parent5ea605d8de5b4438deb4fa86c5231710dd09f934 (diff)
propagate from branch 'au.asn.ucc.matt.ltm.dropbear' (head 2af95f00ebd5bb7a28b3817db1218442c935388e)
to branch 'au.asn.ucc.matt.dropbear' (head ecd779509ef23a8cdf64888904fc9b31d78aa933) --HG-- extra : convert_revision : d26d5eb2837f46b56a33fb0e7573aa0201abd4d5
Diffstat (limited to 'libtomcrypt/src/misc/pkcs5/pkcs_5_2.c')
-rw-r--r--libtomcrypt/src/misc/pkcs5/pkcs_5_2.c129
1 files changed, 129 insertions, 0 deletions
diff --git a/libtomcrypt/src/misc/pkcs5/pkcs_5_2.c b/libtomcrypt/src/misc/pkcs5/pkcs_5_2.c
new file mode 100644
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+++ b/libtomcrypt/src/misc/pkcs5/pkcs_5_2.c
@@ -0,0 +1,129 @@
+/* LibTomCrypt, modular cryptographic library -- Tom St Denis
+ *
+ * LibTomCrypt is a library that provides various cryptographic
+ * algorithms in a highly modular and flexible manner.
+ *
+ * The library is free for all purposes without any express
+ * guarantee it works.
+ *
+ * Tom St Denis, tomstdenis@gmail.com, http://libtomcrypt.com
+ */
+#include <tomcrypt.h>
+
+/**
+ @file pkcs_5_2.c
+ PKCS #5, Algorithm #2, Tom St Denis
+*/
+#ifdef PKCS_5
+
+/**
+ Execute PKCS #5 v2
+ @param password The input password (or key)
+ @param password_len The length of the password (octets)
+ @param salt The salt (or nonce)
+ @param salt_len The length of the salt (octets)
+ @param iteration_count # of iterations desired for PKCS #5 v2 [read specs for more]
+ @param hash_idx The index of the hash desired
+ @param out [out] The destination for this algorithm
+ @param outlen [in/out] The max size and resulting size of the algorithm output
+ @return CRYPT_OK if successful
+*/
+int pkcs_5_alg2(const unsigned char *password, unsigned long password_len,
+ const unsigned char *salt, unsigned long salt_len,
+ int iteration_count, int hash_idx,
+ unsigned char *out, unsigned long *outlen)
+{
+ int err, itts;
+ ulong32 blkno;
+ unsigned long stored, left, x, y;
+ unsigned char *buf[2];
+ hmac_state *hmac;
+
+ LTC_ARGCHK(password != NULL);
+ LTC_ARGCHK(salt != NULL);
+ LTC_ARGCHK(out != NULL);
+ LTC_ARGCHK(outlen != NULL);
+
+ /* test hash IDX */
+ if ((err = hash_is_valid(hash_idx)) != CRYPT_OK) {
+ return err;
+ }
+
+ buf[0] = XMALLOC(MAXBLOCKSIZE * 2);
+ hmac = XMALLOC(sizeof(hmac_state));
+ if (hmac == NULL || buf[0] == NULL) {
+ if (hmac != NULL) {
+ XFREE(hmac);
+ }
+ if (buf[0] != NULL) {
+ XFREE(buf[0]);
+ }
+ return CRYPT_MEM;
+ }
+ /* buf[1] points to the second block of MAXBLOCKSIZE bytes */
+ buf[1] = buf[0] + MAXBLOCKSIZE;
+
+ left = *outlen;
+ blkno = 1;
+ stored = 0;
+ while (left != 0) {
+ /* process block number blkno */
+ zeromem(buf[0], MAXBLOCKSIZE*2);
+
+ /* store current block number and increment for next pass */
+ STORE32H(blkno, buf[1]);
+ ++blkno;
+
+ /* get PRF(P, S||int(blkno)) */
+ if ((err = hmac_init(hmac, hash_idx, password, password_len)) != CRYPT_OK) {
+ goto LBL_ERR;
+ }
+ if ((err = hmac_process(hmac, salt, salt_len)) != CRYPT_OK) {
+ goto LBL_ERR;
+ }
+ if ((err = hmac_process(hmac, buf[1], 4)) != CRYPT_OK) {
+ goto LBL_ERR;
+ }
+ x = MAXBLOCKSIZE;
+ if ((err = hmac_done(hmac, buf[0], &x)) != CRYPT_OK) {
+ goto LBL_ERR;
+ }
+
+ /* now compute repeated and XOR it in buf[1] */
+ XMEMCPY(buf[1], buf[0], x);
+ for (itts = 1; itts < iteration_count; ++itts) {
+ if ((err = hmac_memory(hash_idx, password, password_len, buf[0], x, buf[0], &x)) != CRYPT_OK) {
+ goto LBL_ERR;
+ }
+ for (y = 0; y < x; y++) {
+ buf[1][y] ^= buf[0][y];
+ }
+ }
+
+ /* now emit upto x bytes of buf[1] to output */
+ for (y = 0; y < x && left != 0; ++y) {
+ out[stored++] = buf[1][y];
+ --left;
+ }
+ }
+ *outlen = stored;
+
+ err = CRYPT_OK;
+LBL_ERR:
+#ifdef LTC_CLEAN_STACK
+ zeromem(buf[0], MAXBLOCKSIZE*2);
+ zeromem(hmac, sizeof(hmac_state));
+#endif
+
+ XFREE(hmac);
+ XFREE(buf[0]);
+
+ return err;
+}
+
+#endif
+
+
+/* $Source: /cvs/libtom/libtomcrypt/src/misc/pkcs5/pkcs_5_2.c,v $ */
+/* $Revision: 1.5 $ */
+/* $Date: 2006/03/31 14:15:35 $ */