X-Git-Url: https://pd.if.org/git/?a=blobdiff_plain;f=libtomcrypt%2Fsrc%2Fpk%2Fdsa%2Fdsa_import.c;fp=libtomcrypt%2Fsrc%2Fpk%2Fdsa%2Fdsa_import.c;h=e6a756027230aa6fe169ef2b9d517051aa8e2302;hb=66bc25938679f1d6a1d1200f329093d82a5e99b4;hp=0000000000000000000000000000000000000000;hpb=a52ee0733f420ca20224049260d6fc5cf7d8f621;p=zpackage

diff --git a/libtomcrypt/src/pk/dsa/dsa_import.c b/libtomcrypt/src/pk/dsa/dsa_import.c
new file mode 100644
index 0000000..e6a7560
--- /dev/null
+++ b/libtomcrypt/src/pk/dsa/dsa_import.c
@@ -0,0 +1,152 @@
+/* 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.
+ */
+#include "tomcrypt.h"
+
+/**
+   @file dsa_import.c
+   DSA implementation, import a DSA key, Tom St Denis
+*/
+
+#ifdef LTC_MDSA
+
+/**
+   Import a DSA key
+   @param in       The binary packet to import from
+   @param inlen    The length of the binary packet
+   @param key      [out] Where to store the imported key
+   @return CRYPT_OK if successful, upon error this function will free all allocated memory
+*/
+int dsa_import(const unsigned char *in, unsigned long inlen, dsa_key *key)
+{
+   int           err, stat;
+   unsigned long zero = 0;
+   unsigned char* tmpbuf = NULL;
+   unsigned char flags[1];
+
+   LTC_ARGCHK(in  != NULL);
+   LTC_ARGCHK(key != NULL);
+   LTC_ARGCHK(ltc_mp.name != NULL);
+
+   /* init key */
+   if (mp_init_multi(&key->p, &key->g, &key->q, &key->x, &key->y, NULL) != CRYPT_OK) {
+      return CRYPT_MEM;
+   }
+
+   /* try to match the old libtomcrypt format */
+   err = der_decode_sequence_multi(in, inlen, LTC_ASN1_BIT_STRING, 1UL, flags,
+                                              LTC_ASN1_EOL,        0UL, NULL);
+
+   if (err == CRYPT_OK || err == CRYPT_INPUT_TOO_LONG) {
+       /* private key */
+       if (flags[0] == 1) {
+           if ((err = der_decode_sequence_multi(in, inlen,
+                                  LTC_ASN1_BIT_STRING,   1UL, flags,
+                                  LTC_ASN1_INTEGER,      1UL, key->g,
+                                  LTC_ASN1_INTEGER,      1UL, key->p,
+                                  LTC_ASN1_INTEGER,      1UL, key->q,
+                                  LTC_ASN1_INTEGER,      1UL, key->y,
+                                  LTC_ASN1_INTEGER,      1UL, key->x,
+                                  LTC_ASN1_EOL,          0UL, NULL)) != CRYPT_OK) {
+               goto LBL_ERR;
+           }
+           key->type = PK_PRIVATE;
+           goto LBL_OK;
+       }
+       /* public key */
+       else if (flags[0] == 0) {
+           if ((err = der_decode_sequence_multi(in, inlen,
+                                      LTC_ASN1_BIT_STRING,   1UL, flags,
+                                      LTC_ASN1_INTEGER,      1UL, key->g,
+                                      LTC_ASN1_INTEGER,      1UL, key->p,
+                                      LTC_ASN1_INTEGER,      1UL, key->q,
+                                      LTC_ASN1_INTEGER,      1UL, key->y,
+                                      LTC_ASN1_EOL,          0UL, NULL)) != CRYPT_OK) {
+               goto LBL_ERR;
+           }
+           key->type = PK_PUBLIC;
+           goto LBL_OK;
+       }
+       else {
+          err = CRYPT_INVALID_PACKET;
+          goto LBL_ERR;
+       }
+   }
+   /* get key type */
+   if ((err = der_decode_sequence_multi(in, inlen,
+                          LTC_ASN1_SHORT_INTEGER, 1UL, &zero,
+                          LTC_ASN1_INTEGER,      1UL, key->p,
+                          LTC_ASN1_INTEGER,      1UL, key->q,
+                          LTC_ASN1_INTEGER,      1UL, key->g,
+                          LTC_ASN1_INTEGER,      1UL, key->y,
+                          LTC_ASN1_INTEGER,      1UL, key->x,
+                          LTC_ASN1_EOL,          0UL, NULL)) == CRYPT_OK) {
+
+       key->type = PK_PRIVATE;
+   } else { /* public */
+      ltc_asn1_list params[3];
+      unsigned long tmpbuf_len = inlen;
+
+      LTC_SET_ASN1(params, 0, LTC_ASN1_INTEGER, key->p, 1UL);
+      LTC_SET_ASN1(params, 1, LTC_ASN1_INTEGER, key->q, 1UL);
+      LTC_SET_ASN1(params, 2, LTC_ASN1_INTEGER, key->g, 1UL);
+
+      tmpbuf = XCALLOC(1, tmpbuf_len);
+      if (tmpbuf == NULL) {
+         err = CRYPT_MEM;
+         goto LBL_ERR;
+      }
+
+      err = der_decode_subject_public_key_info(in, inlen, PKA_DSA,
+                                               tmpbuf, &tmpbuf_len,
+                                               LTC_ASN1_SEQUENCE, params, 3);
+      if (err != CRYPT_OK) {
+         XFREE(tmpbuf);
+         goto LBL_ERR;
+      }
+
+      if ((err=der_decode_integer(tmpbuf, tmpbuf_len, key->y)) != CRYPT_OK) {
+         XFREE(tmpbuf);
+         goto LBL_ERR;
+      }
+
+      XFREE(tmpbuf);
+      key->type = PK_PUBLIC;
+   }
+
+LBL_OK:
+   key->qord = mp_unsigned_bin_size(key->q);
+
+   /* quick p, q, g validation, without primality testing */
+   if ((err = dsa_int_validate_pqg(key, &stat)) != CRYPT_OK) {
+      goto LBL_ERR;
+   }
+   if (stat == 0) {
+      err = CRYPT_INVALID_PACKET;
+      goto LBL_ERR;
+   }
+   /* validate x, y */
+   if ((err = dsa_int_validate_xy(key, &stat)) != CRYPT_OK) {
+      goto LBL_ERR;
+   }
+   if (stat == 0) {
+      err = CRYPT_INVALID_PACKET;
+      goto LBL_ERR;
+   }
+
+  return CRYPT_OK;
+LBL_ERR:
+   dsa_free(key);
+   return err;
+}
+
+#endif
+
+/* ref:         $Format:%D$ */
+/* git commit:  $Format:%H$ */
+/* commit time: $Format:%ai$ */