--- /dev/null
+/*
+ * Copyright (c) 1997-1999 The Stanford SRP Authentication Project
+ * All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
+ * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * IN NO EVENT SHALL STANFORD BE LIABLE FOR ANY SPECIAL, INCIDENTAL,
+ * INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND, OR ANY DAMAGES WHATSOEVER
+ * RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER OR NOT ADVISED OF
+ * THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF LIABILITY, ARISING OUT
+ * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ * In addition, the following conditions apply:
+ *
+ * 1. Any software that incorporates the SRP authentication technology
+ * must display the following acknowlegment:
+ * "This product uses the 'Secure Remote Password' cryptographic
+ * authentication system developed by Tom Wu (tjw@CS.Stanford.EDU)."
+ *
+ * 2. Any software that incorporates all or part of the SRP distribution
+ * itself must also display the following acknowledgment:
+ * "This product includes software developed by Tom Wu and Eugene
+ * Jhong for the SRP Distribution (http://srp.stanford.edu/srp/)."
+ *
+ * 3. Redistributions in source or binary form must retain an intact copy
+ * of this copyright notice and list of conditions.
+ */
+
+#include <stdio.h>
+#include "t_defines.h"
+#include "t_pwd.h"
+#include "t_client.h"
+#include "t_sha.h"
+
+_TYPE( struct t_client * )
+t_clientopen(u, n, g, s)
+ const char * u;
+ struct t_num * n;
+ struct t_num * g;
+ struct t_num * s;
+{
+ struct t_client * tc;
+ unsigned char buf1[SHA_DIGESTSIZE], buf2[SHA_DIGESTSIZE];
+ SHA1_CTX ctxt;
+ int i, validated;
+ struct t_preconf * tpc;
+
+ BigInteger nn, gg, n12, r;
+
+ validated = 0;
+ if(n->len < MIN_MOD_BYTES)
+ return 0;
+ for(i = 0; i < t_getprecount(); ++i) {
+ tpc = t_getpreparam(i);
+ if(tpc->modulus.len == n->len && tpc->generator.len == g->len &&
+ memcmp(tpc->modulus.data, n->data, n->len) == 0 &&
+ memcmp(tpc->generator.data, g->data, g->len) == 0) {
+ validated = 1; /* Match found, done */
+ break;
+ }
+ }
+
+ if(validated == 0)
+ return 0;
+
+ if((tc = malloc(sizeof(struct t_client))) == 0)
+ return 0;
+
+ strncpy(tc->username, u, MAXUSERLEN);
+
+ SHA1Init(&tc->hash);
+
+ tc->n.len = n->len;
+ tc->n.data = tc->nbuf;
+ memcpy(tc->n.data, n->data, tc->n.len);
+
+ SHA1Init(&ctxt);
+ SHA1Update(&ctxt, tc->n.data, tc->n.len);
+ SHA1Final(buf1, &ctxt);
+
+ tc->g.len = g->len;
+ tc->g.data = tc->gbuf;
+ memcpy(tc->g.data, g->data, tc->g.len);
+
+ SHA1Init(&ctxt);
+ SHA1Update(&ctxt, tc->g.data, tc->g.len);
+ SHA1Final(buf2, &ctxt);
+
+ for(i = 0; i < sizeof(buf1); ++i)
+ buf1[i] ^= buf2[i];
+
+ SHA1Update(&tc->hash, buf1, sizeof(buf1));
+
+ SHA1Init(&ctxt);
+ SHA1Update(&ctxt, tc->username, strlen(tc->username));
+ SHA1Final(buf1, &ctxt);
+
+ SHA1Update(&tc->hash, buf1, sizeof(buf1));
+
+ tc->s.len = s->len;
+ tc->s.data = tc->sbuf;
+ memcpy(tc->s.data, s->data, tc->s.len);
+
+ SHA1Update(&tc->hash, tc->s.data, tc->s.len);
+
+ tc->a.data = tc->abuf;
+ tc->A.data = tc->Abuf;
+ tc->p.data = tc->pbuf;
+ tc->v.data = tc->vbuf;
+
+ SHA1Init(&tc->ckhash);
+
+ return tc;
+}
+
+_TYPE( struct t_num * )
+t_clientgenexp(tc)
+ struct t_client * tc;
+{
+ BigInteger a, A, n, g;
+
+ if(tc->n.len < ALEN)
+ tc->a.len = tc->n.len;
+ else
+ tc->a.len = ALEN;
+
+ t_random(tc->a.data, tc->a.len);
+ a = BigIntegerFromBytes(tc->a.data, tc->a.len);
+ n = BigIntegerFromBytes(tc->n.data, tc->n.len);
+ g = BigIntegerFromBytes(tc->g.data, tc->g.len);
+ A = BigIntegerFromInt(0);
+ BigIntegerModExp(A, g, a, n);
+ tc->A.len = BigIntegerToBytes(A, tc->A.data);
+
+ BigIntegerFree(A);
+ BigIntegerFree(a);
+ BigIntegerFree(g);
+ BigIntegerFree(n);
+
+ SHA1Update(&tc->hash, tc->A.data, tc->A.len);
+ SHA1Update(&tc->ckhash, tc->A.data, tc->A.len);
+
+ return &tc->A;
+}
+
+_TYPE( void )
+t_clientpasswd(tc, password)
+ struct t_client * tc;
+ char * password;
+{
+ BigInteger n, g, p, v;
+ SHA1_CTX ctxt;
+ unsigned char dig[SHA_DIGESTSIZE];
+
+ n = BigIntegerFromBytes(tc->n.data, tc->n.len);
+ g = BigIntegerFromBytes(tc->g.data, tc->g.len);
+
+ SHA1Init(&ctxt);
+ SHA1Update(&ctxt, tc->username, strlen(tc->username));
+ SHA1Update(&ctxt, ":", 1);
+ SHA1Update(&ctxt, password, strlen(password));
+ SHA1Final(dig, &ctxt);
+
+ SHA1Init(&ctxt);
+ SHA1Update(&ctxt, tc->s.data, tc->s.len);
+ SHA1Update(&ctxt, dig, sizeof(dig));
+ SHA1Final(dig, &ctxt);
+
+ p = BigIntegerFromBytes(dig, sizeof(dig));
+
+ v = BigIntegerFromInt(0);
+ BigIntegerModExp(v, g, p, n);
+
+ tc->p.len = BigIntegerToBytes(p, tc->p.data);
+ BigIntegerFree(p);
+
+ tc->v.len = BigIntegerToBytes(v, tc->v.data);
+ BigIntegerFree(v);
+}
+
+_TYPE( unsigned char * )
+t_clientgetkey(tc, serverval)
+ struct t_client * tc;
+ struct t_num * serverval;
+{
+ BigInteger n, B, v, p, a, sum, S;
+ unsigned char sbuf[MAXPARAMLEN];
+ unsigned char dig[SHA_DIGESTSIZE];
+ unsigned slen;
+ unsigned int u;
+ SHA1_CTX ctxt;
+
+ SHA1Init(&ctxt);
+ SHA1Update(&ctxt, serverval->data, serverval->len);
+ SHA1Final(dig, &ctxt);
+ u = (dig[0] << 24) | (dig[1] << 16) | (dig[2] << 8) | dig[3];
+ if(u == 0)
+ return NULL;
+
+ SHA1Update(&tc->hash, serverval->data, serverval->len);
+
+ B = BigIntegerFromBytes(serverval->data, serverval->len);
+ n = BigIntegerFromBytes(tc->n.data, tc->n.len);
+
+ if(BigIntegerCmp(B, n) >= 0 || BigIntegerCmpInt(B, 0) == 0) {
+ BigIntegerFree(B);
+ BigIntegerFree(n);
+ return NULL;
+ }
+ v = BigIntegerFromBytes(tc->v.data, tc->v.len);
+ if(BigIntegerCmp(B, v) < 0)
+ BigIntegerAdd(B, B, n);
+ BigIntegerSub(B, B, v);
+ BigIntegerFree(v);
+
+ a = BigIntegerFromBytes(tc->a.data, tc->a.len);
+ p = BigIntegerFromBytes(tc->p.data, tc->p.len);
+
+ sum = BigIntegerFromInt(0);
+ BigIntegerMulInt(sum, p, u);
+ BigIntegerAdd(sum, sum, a);
+
+ BigIntegerFree(p);
+ BigIntegerFree(a);
+
+ S = BigIntegerFromInt(0);
+ BigIntegerModExp(S, B, sum, n);
+ slen = BigIntegerToBytes(S, sbuf);
+
+ BigIntegerFree(S);
+ BigIntegerFree(sum);
+ BigIntegerFree(B);
+ BigIntegerFree(n);
+
+ t_sessionkey(tc->session_key, sbuf, slen);
+ memset(sbuf, 0, slen);
+
+ SHA1Update(&tc->hash, tc->session_key, sizeof(tc->session_key));
+
+ SHA1Final(tc->session_response, &tc->hash);
+ SHA1Update(&tc->ckhash, tc->session_response, sizeof(tc->session_response));
+ SHA1Update(&tc->ckhash, tc->session_key, sizeof(tc->session_key));
+
+ return tc->session_key;
+}
+
+_TYPE( int )
+t_clientverify(tc, resp)
+ struct t_client * tc;
+ unsigned char * resp;
+{
+ unsigned char expected[SHA_DIGESTSIZE];
+
+ SHA1Final(expected, &tc->ckhash);
+ return memcmp(expected, resp, sizeof(expected));
+}
+
+_TYPE( unsigned char * )
+t_clientresponse(tc)
+ struct t_client * tc;
+{
+ return tc->session_response;
+}
+
+_TYPE( void )
+t_clientclose(tc)
+ struct t_client * tc;
+{
+ memset(tc->abuf, 0, sizeof(tc->abuf));
+ memset(tc->pbuf, 0, sizeof(tc->pbuf));
+ memset(tc->vbuf, 0, sizeof(tc->vbuf));
+ memset(tc->session_key, 0, sizeof(tc->session_key));
+ free(tc);
+}
projects / openwrt.git / blobdiff