X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ian/git?p=chiark-tcl.git;a=blobdiff_plain;f=crypto%2Fcrypto.c;h=cf50712979a9beb73d6e2f1477070c164d9a0657;hp=7cc2914c65908d6b681617d0989d36c2bc54ba82;hb=da1c2c3cbb87a600f19e250f93ef9fa4f89844fc;hpb=b845521abfac164a92742f984eafb91d5d7c743d

diff --git a/crypto/crypto.c b/crypto/crypto.c
index 7cc2914..cf50712 100644
--- a/crypto/crypto.c
+++ b/crypto/crypto.c
@@ -5,13 +5,8 @@
 
 #include "hbytes.h"
 #include "tables.h"
-#include "serpent.h"
 
-void memxor(Byte *dest, const Byte *src, int l) {
-  while (l--) *dest++ ^= *src++;
-}
-
-const PadMethod padmethods[]= {
+const PadOp padops[]= {
   { "un", 0, 0 },
   { "ua", 0, 1 },
   { "pn", 1, 0 },
@@ -19,35 +14,114 @@ const PadMethod padmethods[]= {
   { 0 }
 };
 
-int do_hbytes_pkcs5(ClientData cd, Tcl_Interp *ip,
-		    const PadMethod *meth, HBytes_Var v, Tcl_Obj *block,
-		    int *ok) {
-  int rc, blocksize, padlen, old_len, i;
-  Byte *padding;
-  const Byte *unpad;
+typedef struct {
+  HBytes_Value *hb;
+  int pad, blocksize; /* 0 or 1 */
+} PadMethodClientData;
+
+int do_hbytes_pad(ClientData cd, Tcl_Interp *ip, const PadOp *op,
+		  HBytes_Var v, Tcl_Obj *blocksz, const PadMethodInfo *meth,
+		  int methargsc, Tcl_Obj *const *methargsv) {
+  PadMethodClientData pmcd;
+  int rc;
   
-  if (meth->use_algname) {
+  if (op->use_algname) {
     const BlockCipherAlgInfo *alg;
-    alg= enum_lookup_cached(ip,block,blockcipheralginfos,"cipher alg for pad");
+    alg= enum_lookup_cached(ip,blocksz,blockcipheralginfos,
+			    "blockcipher alg for pad");
     if (!alg) return TCL_ERROR;
-    blocksize= alg->blocksize;
+    pmcd.blocksize= alg->blocksize;
   } else {
-    rc= Tcl_GetIntFromObj(ip, block, &blocksize);  if (rc) return rc;
-    if (blocksize < 1 || blocksize > 255)
-      return staticerr(ip, "block size out of pkcs#5 range 1..255");
+    rc= Tcl_GetIntFromObj(ip, blocksz, &pmcd.blocksize);  if (rc) return rc;
+    if (pmcd.blocksize < 1) staticerr(ip, "block size must be at least 1", 0);
   }
 
-  if (meth->pad) {
-    padlen= blocksize - (hbytes_len(v.hb) % blocksize);
-    padding= hbytes_append(v.hb, padlen);
+  pmcd.hb= v.hb;
+  pmcd.pad= op->pad;
+
+  return meth->func(&pmcd,ip,methargsc,methargsv);
+}
+  
+int do_padmethodinfo_rfc2406(ClientData cd, Tcl_Interp *ip,
+			     Tcl_Obj *nxthdr_arg, int *ok) {
+  const PadMethodClientData *pmcd= (const void*)cd;
+  int i, rc, padlen, old_len;
+  
+  if (pmcd->blocksize > 256)
+    return staticerr(ip, "block size too large for RFC2406 padding", 0);
+
+  if (pmcd->pad) {
+    Byte *padding;
+    HBytes_Value nxthdr;
+
+    rc= pat_hb(ip,nxthdr_arg,&nxthdr);
+    if (rc) return rc;
+
+    if (hbytes_len(&nxthdr) != 1) return
+      staticerr(ip, "RFC2406 next header field must be exactly 1 byte", 0);
+    padlen= pmcd->blocksize-1 - ((hbytes_len(pmcd->hb)+1) % pmcd->blocksize);
+    padding= hbytes_append(pmcd->hb, padlen+2);
+    for (i=1; i<=padlen; i++)
+      *padding++ = i;
+    *padding++ = padlen;
+    *padding++ = hbytes_data(&nxthdr)[0];
+    *ok= 1;
+    
+  } else {
+    const Byte *padding, *trailer;
+    HBytes_Value nxthdr;
+    Tcl_Obj *nxthdr_valobj, *ro;
+    
+    *ok= 0;
+    old_len= hbytes_len(pmcd->hb);  if (old_len % pmcd->blocksize) goto quit;
+    trailer= hbytes_unappend(pmcd->hb, 2); if (!trailer) goto quit;
+
+    padlen= trailer[0];
+    hbytes_array(&nxthdr,trailer+1,1);
+    nxthdr_valobj= ret_hb(ip,nxthdr);
+    ro= Tcl_ObjSetVar2(ip,nxthdr_arg,0,nxthdr_valobj,TCL_LEAVE_ERR_MSG);
+    if (!ro) { Tcl_DecrRefCount(nxthdr_valobj); return TCL_ERROR; }
+
+    padding= hbytes_unappend(pmcd->hb, padlen);
+    for (i=1; i<=padlen; i++)
+      if (*padding++ != i) goto quit;
+
+    *ok= 1;
+
+  quit:;
+
+  }
+
+  return TCL_OK;
+}
+
+int do_padmethodinfo_pkcs5(ClientData cd, Tcl_Interp *ip, int *ok) {
+  const PadMethodClientData *pmcd= (const void*)cd;
+  int padlen, old_len, i;
+  
+  if (pmcd->blocksize > 255)
+    return staticerr(ip, "block size too large for pkcs#5", 0);
+
+  if (pmcd->pad) {
+
+    Byte *padding;
+
+    padlen= pmcd->blocksize - (hbytes_len(pmcd->hb) % pmcd->blocksize);
+    padding= hbytes_append(pmcd->hb, padlen);
     memset(padding, padlen, padlen);
+
   } else {
-    old_len= hbytes_len(v.hb);  if (old_len % blocksize) goto bad;
-    unpad= hbytes_unappend(v.hb, 1);  if (!unpad) goto bad;
-    padlen= *unpad;
-    if (padlen < 1 || padlen > blocksize) goto bad;
-    unpad= hbytes_unappend(v.hb, padlen-1);  if (!unpad) goto bad;
-    for (i=0; i<padlen-1; i++, unpad++) if (*unpad != padlen) goto bad;
+
+    const Byte *padding;
+
+    old_len= hbytes_len(pmcd->hb);  if (old_len % pmcd->blocksize) goto bad;
+    padding= hbytes_unappend(pmcd->hb, 1);  if (!padding) goto bad;
+    padlen= *padding;
+    if (padlen < 1 || padlen > pmcd->blocksize) goto bad;
+    padding= hbytes_unappend(pmcd->hb, padlen-1);  if (!padding) goto bad;
+
+    for (i=0; i<padlen-1; i++, padding++) if (*padding != padlen) goto bad;
+
   }
 
   *ok= 1;
@@ -102,6 +176,7 @@ static void key_t_dup(Tcl_Obj *src_obj, Tcl_Obj *dup_obj) {
   memcpy(dup->value, src->value, src->valuelen);
   noalg(dup);
   dup_obj->internalRep.otherValuePtr= dup;
+  dup_obj->typePtr= &blockcipherkey_type;
 }
 
 static void key_t_ustr(Tcl_Obj *o) {
@@ -133,8 +208,8 @@ Tcl_ObjType blockcipherkey_type = {
   key_t_free, key_t_dup, key_t_ustr, key_t_sfa
 };
 
-CiphKeyValue *get_key(Tcl_Interp *ip, Tcl_Obj *key_obj,
-		      const void *alg, int want_bufferslen) {
+static CiphKeyValue *get_key(Tcl_Interp *ip, Tcl_Obj *key_obj,
+			     const void *alg, int want_bufferslen) {
   CiphKeyValue *key;
   int rc;
   
@@ -155,67 +230,147 @@ CiphKeyValue *get_key(Tcl_Interp *ip, Tcl_Obj *key_obj,
   return key;
 }
 
-int do_hbytes_blockcipher(ClientData cd, Tcl_Interp *ip, int encrypt,
-			  HBytes_Var v, const BlockCipherAlgInfo *alg,
-			  Tcl_Obj *key_obj, const BlockCipherModeInfo *mode,
-			  HBytes_Value iv, HBytes_Value *result) {
-  int rc, want_bufferslen, data_len, iv_want;
-  CiphKeyValue *key;
-  const char *failure;
+int do_hbytes_blockcipher(ClientData cd, Tcl_Interp *ip,
+			  const BlockCipherOp *op,
+			  int objc, Tcl_Obj *const *objv) {
+  return op->func((void*)op,ip,objc,objv);
+}
+
+static int blockcipher_prep(Tcl_Interp *ip, Tcl_Obj *key_obj,
+			    const HBytes_Value *iv, int decrypt,
+			    const BlockCipherAlgInfo *alg,
+			    const BlockCipherModeInfo *mode, int data_len,
+			    const CiphKeyValue **key_r, const void **sched_r,
+			    const Byte **iv_r, int *iv_lenbytes_r,
+			    Byte **buffers_r, int *nblocks_r) {
   void *sched, **schedp;
+  int want_bufferslen, want_iv;
+  int rc;
+  CiphKeyValue *key;
+
+  if (data_len % alg->blocksize)
+    return staticerr(ip, "block cipher input not whole number of blocks",
+		     "HBYTES BLOCKCIPHER LENGTH");
 
   want_bufferslen= alg->blocksize * (mode->buf_blocks + mode->iv_blocks);
-  key= get_key(ip, key_obj, alg, want_bufferslen);
+  key= get_key(ip, key_obj, alg, want_bufferslen);  if (!key) return TCL_ERROR;
 
   schedp= (alg->decrypt.make_schedule==alg->encrypt.make_schedule
-	   || encrypt) ? &key->alpha : &key->beta;
+	   || !decrypt) ? &key->alpha : &key->beta;
   sched= *schedp;
   if (!sched) {
-    if (key->valuelen < alg->key_min) return staticerr(ip, "key too short");
-    if (key->valuelen > alg->key_max) return staticerr(ip, "key too long");
+    if (key->valuelen < alg->key_min)
+      return staticerr(ip, "key too short", "HBYTES BLOCKCIPHER PARAMS");
+    if (key->valuelen > alg->key_max)
+      return staticerr(ip, "key too long", "HBYTES BLOCKCIPHER PARAMS");
 
     sched= TALLOC(alg->schedule_size);
-    (encrypt ? &alg->encrypt : &alg->decrypt)->make_schedule
+    (decrypt ? &alg->decrypt : &alg->encrypt)->make_schedule
       (sched, key->value, key->valuelen);
     *schedp= sched;
   }
 
-  iv_want= alg->blocksize * mode->iv_blocks;
-  if (hbytes_issentinel(&iv)) {
-    if (!encrypt) return staticerr(ip,"must supply iv when decrypting");
-    rc= get_urandom(ip, key->buffers, iv_want);
+  want_iv= alg->blocksize * mode->iv_blocks;
+  if (!want_iv) {
+    if (!hbytes_issentinel(iv))
+      return staticerr(ip,"iv supplied but mode does not take one", 0);
+  } else if (hbytes_issentinel(iv)) {
+    if (decrypt) return staticerr(ip,"must supply iv when decrypting", 0);
+    rc= get_urandom(ip, key->buffers, want_iv);
     if (rc) return rc;
   } else {
-    int iv_supplied= hbytes_len(&iv);
-    if (iv_supplied > iv_want)
-      return staticerr(ip, "iv too large for algorithm and mode");
-    memcpy(key->buffers, hbytes_data(&iv), iv_supplied);
-    memset(key->buffers + iv_supplied, 0, iv_want - iv_supplied);
+    int iv_supplied= hbytes_len(iv);
+    if (iv_supplied > want_iv)
+      return staticerr(ip, "iv too large for algorithm and mode",
+		       "HBYTES BLOCKCIPHER PARAMS");
+    memcpy(key->buffers, hbytes_data(iv), iv_supplied);
+    memset(key->buffers + iv_supplied, 0, want_iv - iv_supplied);
   }
 
-  data_len= hbytes_len(v.hb);
-  if (data_len % alg->blocksize)
-    return staticerr(ip, "block cipher input not whole number of blocks");
+  *key_r= key;
+  *sched_r= sched;
+
+  *iv_r= key->buffers;
+  *iv_lenbytes_r= want_iv;
+
+  *buffers_r= key->buffers + want_iv;
+  *nblocks_r= data_len / alg->blocksize;
+  
+  return TCL_OK;
+}
+
+int do_blockcipherop_d(ClientData cd, Tcl_Interp *ip,
+		       HBytes_Var v, const BlockCipherAlgInfo *alg,
+		       Tcl_Obj *key_obj, const BlockCipherModeInfo *mode,
+		       HBytes_Value iv, HBytes_Value *result) {
+  return do_blockcipherop_e(cd,ip,v,alg,key_obj,mode,iv,result);
+}
 
+int do_blockcipherop_e(ClientData cd, Tcl_Interp *ip,
+		       HBytes_Var v, const BlockCipherAlgInfo *alg,
+		       Tcl_Obj *key_obj, const BlockCipherModeInfo *mode,
+		       HBytes_Value iv, HBytes_Value *result) {
+  const BlockCipherOp *op= (const void*)cd;
+  int encrypt= op->encrypt;
+  int rc, iv_lenbytes;
+  const CiphKeyValue *key;
+  const char *failure;
+  const Byte *ivbuf;
+  Byte *buffers;
+  const void *sched;
+  int nblocks;
+
+  if (!mode->encrypt)
+    return staticerr(ip, "mode does not support encrypt/decrypt", 0);
+
+  rc= blockcipher_prep(ip,key_obj,&iv,!encrypt,
+		       alg,mode, hbytes_len(v.hb),
+		       &key,&sched,
+		       &ivbuf,&iv_lenbytes,
+		       &buffers,&nblocks);
+  if (rc) return rc;
+  
   failure=
     (encrypt ? mode->encrypt : mode->decrypt)
-    (hbytes_data(v.hb), data_len / alg->blocksize,
-     key->buffers, key->buffers + iv_want,
-     alg, encrypt,
-     alg->blocksize, sched);
+    (hbytes_data(v.hb), nblocks, ivbuf, buffers, alg, encrypt, sched);
 
   if (failure)
-    return staticerr(ip, failure);
+    return staticerr(ip, failure, "HBYTES BLOCKCIPHER CRYPTFAIL CRYPT");
 
-  hbytes_array(result, key->buffers, iv_want);
+  hbytes_array(result, ivbuf, iv_lenbytes);
 
   return TCL_OK;
 }
 
-static void dbuf(const char *m, const Byte *a, int l) {
-  fprintf(stderr,"dbuf %s l=%d ",m,l);
-  while (l-->0) fprintf(stderr,"%02x",*a++);
-  putc('\n',stderr);
+int do_blockcipherop_mac(ClientData cd, Tcl_Interp *ip,
+			 HBytes_Value msg, const BlockCipherAlgInfo *alg,
+			 Tcl_Obj *key_obj, const BlockCipherModeInfo *mode,
+			 HBytes_Value iv, HBytes_Value *result) {
+  const CiphKeyValue *key;
+  const char *failure;
+  const Byte *ivbuf;
+  Byte *buffers;
+  const void *sched;
+  int nblocks, iv_lenbytes;
+  int rc;
+
+  if (!mode->mac)
+    return staticerr(ip, "mode does not support mac generation", 0);
+  
+  rc= blockcipher_prep(ip,key_obj,&iv,0,
+		       alg,mode, hbytes_len(&msg),
+		       &key,&sched,
+		       &ivbuf,&iv_lenbytes,
+		       &buffers,&nblocks);
+  if (rc) return rc;
+
+  failure= mode->mac(hbytes_data(&msg), nblocks, ivbuf, buffers, alg, sched);
+  if (failure)
+    return staticerr(ip,failure, "HBYTES BLOCKCIPHER CRYPTFAIL MAC");
+
+  hbytes_array(result, buffers, alg->blocksize * mode->mac_blocks);
+
+  return TCL_OK;
 }
 
 int do_hbytes_hmac(ClientData cd, Tcl_Interp *ip, const HashAlgInfo *alg,
@@ -232,7 +387,8 @@ int do_hbytes_hmac(ClientData cd, Tcl_Interp *ip, const HashAlgInfo *alg,
   if (maclen_obj) {
     rc= Tcl_GetIntFromObj(ip, maclen_obj, &ml);  if (rc) return rc;
     if (ml<0 || ml>alg->hashsize)
-      return staticerr(ip, "requested hmac output size out of range");
+      return staticerr(ip, "requested hmac output size out of range",
+		       "HBYTES HMAC PARAMS");
   } else {
     ml= alg->hashsize;
   }
@@ -245,23 +401,21 @@ int do_hbytes_hmac(ClientData cd, Tcl_Interp *ip, const HashAlgInfo *alg,
     assert(!key->beta);
     
     if (key->valuelen > alg->blocksize)
-      return staticerr(ip, "key to hmac longer than hash block size");
+      return staticerr(ip, "key to hmac longer than hash block size",
+		       "HBYTES HMAC PARAMS");
 
-dbuf("start key",key->value,key->valuelen);
     memcpy(key->buffers, key->value, key->valuelen);
     memset(key->buffers + key->valuelen, 0, alg->blocksize - key->valuelen);
     for (i=0; i<alg->blocksize; i++) key->buffers[i] ^= 0x36;
 
     key->alpha= TALLOC(alg->statesize);
     alg->init(key->alpha);
-dbuf("inner key",key->buffers,alg->blocksize);
     alg->update(key->alpha, key->buffers, alg->blocksize);
     
     key->beta= TALLOC(alg->statesize);
     alg->init(key->beta);
     for (i=0; i<alg->blocksize; i++) key->buffers[i] ^= (0x5c ^ 0x36);
     alg->update(key->beta, key->buffers, alg->blocksize);
-dbuf("inner key",key->buffers,alg->blocksize);
   }
   assert(key->beta);
 
@@ -270,14 +424,26 @@ dbuf("inner key",key->buffers,alg->blocksize);
   memcpy(key->buffers, key->alpha, alg->statesize);
   alg->update(key->buffers, hbytes_data(&message), hbytes_len(&message));
   alg->final(key->buffers, dest);
-dbuf("inner hash",dest,alg->hashsize);
 
   memcpy(key->buffers, key->beta, alg->statesize);
   alg->update(key->buffers, dest, alg->hashsize);
   alg->final(key->buffers, dest);
-dbuf("outer hash",dest,alg->hashsize);
 
   hbytes_unappend(result, alg->hashsize - ml);
 
   return TCL_OK;
 }
+
+int do_blockcipherop_prop(ClientData cd, Tcl_Interp *ip,
+			  const BlockCipherPropInfo *prop,
+			  const BlockCipherAlgInfo *alg, int *result) {
+  *result= *(const int*)((const char*)alg + prop->int_offset);
+  return TCL_OK;
+}
+
+int do_hbytes_hash_prop(ClientData cd, Tcl_Interp *ip,
+			const HashAlgPropInfo *prop,
+			const HashAlgInfo *alg, int *result) {
+  *result= *(const int*)((const char*)alg + prop->int_offset);
+  return TCL_OK;
+}