xfnw/plan9fox
1
0
Fork 0
Code Issues Pull requests Projects Releases Wiki Activity

devtls: zero secret information before freeing, cleanup

Browse source
This commit is contained in:
cinap_lenrek 2016-03-23 13:50:58 +01:00
parent 44b80d48af
commit e7bc98b057
1 changed files with 25 additions and 28 deletions
Download patch file Download diff file Expand all files Collapse all files

51
sys/src/9/port/devtls.c
View file

@ -1,5 +1,5 @@
/* /*
* devtls - record layer for transport layer security 1.0 and secure sockets layer 3.0 * devtls - record layer for transport layer security 1.2 and secure sockets layer 3.0
*/ */
#include "u.h" #include "u.h"
#include "../port/lib.h" #include "../port/lib.h"
@ -83,17 +83,18 @@ struct Secret
{ {
char *encalg; /* name of encryption alg */ char *encalg; /* name of encryption alg */
char *hashalg; /* name of hash alg */ char *hashalg; /* name of hash alg */
int (*enc)(Secret*, uchar*, int);
int (*dec)(Secret*, uchar*, int);
int (*unpad)(uchar*, int, int);
DigestState *(*mac)(uchar*, ulong, uchar*, ulong, uchar*, DigestState*);
int (*aead_enc)(Secret*, uchar*, int, uchar*, uchar*, int); int (*aead_enc)(Secret*, uchar*, int, uchar*, uchar*, int);
int (*aead_dec)(Secret*, uchar*, int, uchar*, uchar*, int); int (*aead_dec)(Secret*, uchar*, int, uchar*, uchar*, int);
int (*enc)(Secret*, uchar*, int);
int (*dec)(Secret*, uchar*, int);
int (*unpad)(uchar*, int, int);
DigestState* (*mac)(uchar*, ulong, uchar*, ulong, uchar*, DigestState*);
int block; /* encryption block len, 0 if none */ int block; /* encryption block len, 0 if none */
int maclen; int maclen; /* # bytes of record mac / authentication tag */
int recivlen; int recivlen; /* # bytes of record iv for AEAD ciphers */
void *enckey; void *enckey;
uchar mackey[MaxMacLen]; uchar mackey[MaxMacLen];
}; };
@ -1428,7 +1429,6 @@ initmd5key(Hashalg *ha, int version, Secret *s, uchar *p)
static void static void
initclearmac(Hashalg *, int, Secret *s, uchar *) initclearmac(Hashalg *, int, Secret *s, uchar *)
{ {
s->maclen = 0;
s->mac = nomac; s->mac = nomac;
} }
@ -1489,7 +1489,6 @@ initRC4key(Encalg *ea, Secret *s, uchar *p, uchar *)
s->enckey = smalloc(sizeof(RC4state)); s->enckey = smalloc(sizeof(RC4state));
s->enc = rc4enc; s->enc = rc4enc;
s->dec = rc4enc; s->dec = rc4enc;
s->block = 0;
setupRC4state(s->enckey, p, ea->keylen); setupRC4state(s->enckey, p, ea->keylen);
} }
@ -1517,12 +1516,8 @@ static void
initccpolykey(Encalg *ea, Secret *s, uchar *p, uchar *iv) initccpolykey(Encalg *ea, Secret *s, uchar *p, uchar *iv)
{ {
s->enckey = smalloc(sizeof(Chachastate)); s->enckey = smalloc(sizeof(Chachastate));
s->enc = noenc;
s->dec = noenc;
s->mac = nomac;
s->aead_enc = ccpoly_aead_enc; s->aead_enc = ccpoly_aead_enc;
s->aead_dec = ccpoly_aead_dec; s->aead_dec = ccpoly_aead_dec;
s->block = 0;
s->maclen = Poly1305dlen; s->maclen = Poly1305dlen;
if(ea->ivlen == 0) { if(ea->ivlen == 0) {
/* older draft version, iv is 64-bit sequence number */ /* older draft version, iv is 64-bit sequence number */
@ -1538,12 +1533,8 @@ static void
initaesgcmkey(Encalg *ea, Secret *s, uchar *p, uchar *iv) initaesgcmkey(Encalg *ea, Secret *s, uchar *p, uchar *iv)
{ {
s->enckey = smalloc(sizeof(AESGCMstate)); s->enckey = smalloc(sizeof(AESGCMstate));
s->enc = noenc;
s->dec = noenc;
s->mac = nomac;
s->aead_enc = aesgcm_aead_enc; s->aead_enc = aesgcm_aead_enc;
s->aead_dec = aesgcm_aead_dec; s->aead_dec = aesgcm_aead_dec;
s->block = 0;
s->maclen = 16; s->maclen = 16;
s->recivlen = 8; s->recivlen = 8;
memmove(s->mackey, iv, ea->ivlen); memmove(s->mackey, iv, ea->ivlen);
@ -1556,7 +1547,6 @@ initclearenc(Encalg *, Secret *s, uchar *, uchar *)
{ {
s->enc = noenc; s->enc = noenc;
s->dec = noenc; s->dec = noenc;
s->block = 0;
} }
static Encalg encrypttab[] = static Encalg encrypttab[] =
@ -1700,29 +1690,29 @@ tlswrite(Chan *c, void *a, long n, vlong off)
p = cb->f[4]; p = cb->f[4];
m = (strlen(p)*3)/2; m = (strlen(p)*3)/2;
x = smalloc(m); x = smalloc(m);
tos = nil; tos = smalloc(sizeof(Secret));
toc = nil; toc = smalloc(sizeof(Secret));
if(waserror()){ if(waserror()){
freeSec(tos); freeSec(tos);
freeSec(toc); freeSec(toc);
free(x); free(x);
nexterror(); nexterror();
} }
m = dec64(x, m, p, strlen(p)); m = dec64(x, m, p, strlen(p));
if(m < 2 * ha->maclen + 2 * ea->keylen + 2 * ea->ivlen) if(m < 2 * ha->maclen + 2 * ea->keylen + 2 * ea->ivlen)
error("not enough secret data provided"); error("not enough secret data provided");
tos = smalloc(sizeof(Secret));
toc = smalloc(sizeof(Secret));
if(!ha->initkey || !ea->initkey) if(!ha->initkey || !ea->initkey)
error("misimplemented secret algorithm"); error("misimplemented secret algorithm");
(*ha->initkey)(ha, tr->version, tos, &x[0]); (*ha->initkey)(ha, tr->version, tos, &x[0]);
(*ha->initkey)(ha, tr->version, toc, &x[ha->maclen]); (*ha->initkey)(ha, tr->version, toc, &x[ha->maclen]);
(*ea->initkey)(ea, tos, &x[2 * ha->maclen], &x[2 * ha->maclen + 2 * ea->keylen]); (*ea->initkey)(ea, tos, &x[2 * ha->maclen], &x[2 * ha->maclen + 2 * ea->keylen]);
(*ea->initkey)(ea, toc, &x[2 * ha->maclen + ea->keylen], &x[2 * ha->maclen + 2 * ea->keylen + ea->ivlen]); (*ea->initkey)(ea, toc, &x[2 * ha->maclen + ea->keylen], &x[2 * ha->maclen + 2 * ea->keylen + ea->ivlen]);
if(!tos->mac || !tos->enc || !tos->dec if(!tos->aead_enc || !tos->aead_dec || !toc->aead_enc || !toc->aead_dec)
|| !toc->mac || !toc->enc || !toc->dec) if(!tos->mac || !tos->enc || !tos->dec || !toc->mac || !toc->enc || !toc->dec)
error("missing algorithm implementations"); error("missing algorithm implementations");
if(strtol(cb->f[3], nil, 0) == 0){ if(strtol(cb->f[3], nil, 0) == 0){
@ -2073,10 +2063,17 @@ tlsstate(int s)
static void static void
freeSec(Secret *s) freeSec(Secret *s)
{ {
if(s != nil){ void *k;
free(s->enckey);
free(s); if(s == nil)
return;
k = s->enckey;
if(k != nil){
memset(k, 0, msize(k));
free(k);
} }
memset(s, 0, sizeof(*s));
free(s);
} }
static int static int