#include "libcurl.h"
cvar_t crypto_developer = {CVAR_SAVE, "crypto_developer", "0", "print extra info about crypto handshake"};
+cvar_t crypto_aeslevel = {CVAR_SAVE, "crypto_aeslevel", "1", "whether to support AES encryption in authenticated connections (0 = no, 1 = supported, 2 = requested, 3 = required)"};
+
cvar_t crypto_servercpupercent = {CVAR_SAVE, "crypto_servercpupercent", "10", "allowed crypto CPU load in percent for server operation (0 = no limit, faster)"};
cvar_t crypto_servercpumaxtime = {CVAR_SAVE, "crypto_servercpumaxtime", "0.01", "maximum allowed crypto CPU time per frame (0 = no limit)"};
cvar_t crypto_servercpudebug = {CVAR_SAVE, "crypto_servercpudebug", "0", "print statistics about time usage by crypto"};
static double crypto_servercpu_accumulator = 0;
static double crypto_servercpu_lastrealtime = 0;
-cvar_t crypto_aeslevel = {CVAR_SAVE, "crypto_aeslevel", "1", "whether to support AES encryption in authenticated connections (0 = no, 1 = supported, 2 = requested, 3 = required)"};
+
+extern cvar_t net_sourceaddresscheck;
+
int crypto_keyfp_recommended_length;
static const char *crypto_idstring = NULL;
static char crypto_idstring_buf[512];
+
#define PROTOCOL_D0_BLIND_ID FOURCC_D0PK
#define PROTOCOL_VLEN (('v' << 0) | ('l' << 8) | ('e' << 16) | ('n' << 24))
char challenge[2048];
char wantserver_idfp[FP64_SIZE+1];
qboolean wantserver_aes;
+ qboolean wantserver_issigned;
int cdata_id;
}
crypto_data_t;
int keyid;
char idfp[FP64_SIZE+1];
int aeslevel;
+ qboolean issigned;
}
crypto_storedhostkey_t;
static crypto_storedhostkey_t *crypto_storedhostkey_hashtable[CRYPTO_HOSTKEY_HASHSIZE];
int keyid;
char idfp[FP64_SIZE+1];
int aeslevel;
+ qboolean issigned;
if(!d0_blind_id_dll)
return;
++keystring;
keyid = -1;
+ issigned = false;
while(*keystring && keyid < 0)
{
// id@key
const char *idstart, *idend, *keystart, *keyend;
+ qboolean thisissigned = true;
++keystring; // skip the space
idstart = keystring;
while(*keystring && *keystring != ' ' && *keystring != '@')
++keystring;
keyend = keystring;
+ if (keystart[0] == '~')
+ {
+ thisissigned = false;
+ ++keystart;
+ }
+
if(idend - idstart == FP64_SIZE && keyend - keystart == FP64_SIZE)
{
- for(keyid = MAX_PUBKEYS - 1; keyid >= 0; --keyid)
- if(pubkeys[keyid])
- if(!memcmp(pubkeys_fp64[keyid], keystart, FP64_SIZE))
+ int thiskeyid;
+ for(thiskeyid = MAX_PUBKEYS - 1; thiskeyid >= 0; --thiskeyid)
+ if(pubkeys[thiskeyid])
+ if(!memcmp(pubkeys_fp64[thiskeyid], keystart, FP64_SIZE))
{
memcpy(idfp, idstart, FP64_SIZE);
idfp[FP64_SIZE] = 0;
+ keyid = thiskeyid;
+ issigned = thisissigned;
break;
}
// If this failed, keyid will be -1.
Con_Printf("Server %s tried to change the host key to a value not in the host cache. Connecting to it will fail. To accept the new host key, do crypto_hostkey_clear %s\n", buf, buf);
if(hk->aeslevel > aeslevel)
Con_Printf("Server %s tried to reduce encryption status, not accepted. Connecting to it will fail. To accept, do crypto_hostkey_clear %s\n", buf, buf);
+ if(hk->issigned > issigned)
+ Con_Printf("Server %s tried to reduce signature status, not accepted. Connecting to it will fail. To accept, do crypto_hostkey_clear %s\n", buf, buf);
}
hk->aeslevel = max(aeslevel, hk->aeslevel);
+ hk->issigned = issigned;
return;
}
memcpy(hk->idfp, idfp, FP64_SIZE+1);
hk->next = crypto_storedhostkey_hashtable[hashindex];
hk->aeslevel = aeslevel;
+ hk->issigned = issigned;
crypto_storedhostkey_hashtable[hashindex] = hk;
}
-qboolean Crypto_RetrieveHostKey(lhnetaddress_t *peeraddress, int *keyid, char *keyfp, size_t keyfplen, char *idfp, size_t idfplen, int *aeslevel)
+qboolean Crypto_RetrieveHostKey(lhnetaddress_t *peeraddress, int *keyid, char *keyfp, size_t keyfplen, char *idfp, size_t idfplen, int *aeslevel, qboolean *issigned)
{
char buf[128];
int hashindex;
strlcpy(idfp, hk->idfp, idfplen);
if(aeslevel)
*aeslevel = hk->aeslevel;
+ if(issigned)
+ *issigned = hk->issigned;
return true;
}
return true;
}
+static void Crypto_BuildIdString(void)
+{
+ int i;
+ char vabuf[1024];
+
+ crypto_idstring = NULL;
+ dpsnprintf(crypto_idstring_buf, sizeof(crypto_idstring_buf), "%d", d0_rijndael_dll ? crypto_aeslevel.integer : 0);
+ for (i = 0; i < MAX_PUBKEYS; ++i)
+ if (pubkeys[i])
+ strlcat(crypto_idstring_buf, va(vabuf, sizeof(vabuf), " %s@%s%s", pubkeys_priv_fp64[i], pubkeys_havesig[i] ? "" : "~", pubkeys_fp64[i]), sizeof(crypto_idstring_buf));
+ crypto_idstring = crypto_idstring_buf;
+}
+
void Crypto_LoadKeys(void)
{
char buf[8192];
// PUBLIC KEYS to accept (including modulus)
// PRIVATE KEY of user
- crypto_idstring = NULL;
- dpsnprintf(crypto_idstring_buf, sizeof(crypto_idstring_buf), "%d", d0_rijndael_dll ? crypto_aeslevel.integer : 0);
for(i = 0; i < MAX_PUBKEYS; ++i)
{
memset(pubkeys_fp64[i], 0, sizeof(pubkeys_fp64[i]));
if(qd0_blind_id_verify_private_id(pubkeys[i]) && qd0_blind_id_verify_public_id(pubkeys[i], &status))
{
pubkeys_havepriv[i] = true;
- strlcat(crypto_idstring_buf, va(vabuf, sizeof(vabuf), " %s@%s", pubkeys_priv_fp64[i], pubkeys_fp64[i]), sizeof(crypto_idstring_buf));
+ pubkeys_havesig[i] = status;
// verify the key we just got (just in case)
- if(status)
- pubkeys_havesig[i] = true;
- else
+ if(!status)
Con_Printf("NOTE: this ID has not yet been signed!\n");
Crypto_SavePubKeyTextFile(i);
}
}
}
- crypto_idstring = crypto_idstring_buf;
keygen_i = -1;
+ Crypto_BuildIdString();
Crypto_BuildChallengeAppend();
// find a good prefix length for all the keys we know (yes, algorithm is not perfect yet, may yield too long prefix length)
return;
}
- if(keygen_i >= MAX_PUBKEYS || !pubkeys[keygen_i])
+ if(keygen_i < 0)
{
- Con_Printf("overflow of keygen_i\n");
- keygen_i = -1;
+ Con_Printf("Unexpected response from keygen server:\n");
+ Com_HexDumpToConsole(buffer, (int)length_received);
SV_UnlockThreadMutex();
return;
}
- if(keygen_i < 0)
+ if(keygen_i >= MAX_PUBKEYS || !pubkeys[keygen_i])
{
- Con_Printf("Unexpected response from keygen server:\n");
- Com_HexDumpToConsole(buffer, (int)length_received);
+ Con_Printf("overflow of keygen_i\n");
+ keygen_i = -1;
SV_UnlockThreadMutex();
return;
}
Con_Printf("Saved to key_%d.d0si%s\n", keygen_i, sessionid.string);
+ Crypto_BuildIdString();
+
keygen_i = -1;
SV_UnlockThreadMutex();
}
break;
// if the challenge is not recognized, drop the packet
if (i == MAX_CHALLENGES) // challenge mismatch is silent
- return CRYPTO_DISCARD; // pre-challenge: rather be silent
+ return Crypto_SoftServerError(data_out, len_out, "missing challenge in connect");
crypto = Crypto_ServerFindInstance(peeraddress, false);
if(!crypto || !crypto->authenticated)
id = (cnt ? atoi(cnt) : -1);
cnt = InfoString_GetValue(string + 4, "cnt", infostringvalue, sizeof(infostringvalue));
if(!cnt)
- return CRYPTO_DISCARD; // pre-challenge: rather be silent
+ return Crypto_SoftServerError(data_out, len_out, "missing cnt in d0pk");
GetUntilNul(&data_in, &len_in);
if(!data_in)
- return CRYPTO_DISCARD; // pre-challenge: rather be silent
+ return Crypto_SoftServerError(data_out, len_out, "missing appended data in d0pk");
if(!strcmp(cnt, "0"))
{
int i;
if (!(s = InfoString_GetValue(string + 4, "challenge", infostringvalue, sizeof(infostringvalue))))
- return CRYPTO_DISCARD; // pre-challenge: rather be silent
+ return Crypto_SoftServerError(data_out, len_out, "missing challenge in d0pk\\0");
// validate the challenge
for (i = 0;i < MAX_CHALLENGES;i++)
if(challenge[i].time > 0)
if (!LHNETADDRESS_Compare(peeraddress, &challenge[i].address) && !strcmp(challenge[i].string, s))
break;
// if the challenge is not recognized, drop the packet
- if (i == MAX_CHALLENGES) // challenge mismatch is silent
- return CRYPTO_DISCARD; // pre-challenge: rather be silent
+ if (i == MAX_CHALLENGES)
+ return Crypto_SoftServerError(data_out, len_out, "invalid challenge in d0pk\\0");
if (!(s = InfoString_GetValue(string + 4, "aeslevel", infostringvalue, sizeof(infostringvalue))))
aeslevel = 0; // not supported
// I am the server, and my key is ok... so let's set server_keyfp and server_idfp
strlcpy(crypto->server_keyfp, pubkeys_fp64[CDATA->s], sizeof(crypto->server_keyfp));
strlcpy(crypto->server_idfp, pubkeys_priv_fp64[CDATA->s], sizeof(crypto->server_idfp));
+ crypto->server_issigned = pubkeys_havesig[CDATA->s];
if(!CDATA->id)
CDATA->id = qd0_blind_id_new();
CLEAR_CDATA;
return Crypto_ServerError(data_out, len_out, "d0_blind_id_authenticate_with_private_id_verify failed (authentication error)", "Authentication error");
}
- if(status)
- strlcpy(crypto->client_keyfp, pubkeys_fp64[CDATA->c], sizeof(crypto->client_keyfp));
- else
- crypto->client_keyfp[0] = 0;
+ strlcpy(crypto->client_keyfp, pubkeys_fp64[CDATA->c], sizeof(crypto->client_keyfp));
+ crypto->client_issigned = status;
+
memset(crypto->client_idfp, 0, sizeof(crypto->client_idfp));
fpbuflen = FP64_SIZE;
if(!qd0_blind_id_fingerprint64_public_id(CDATA->id, crypto->client_idfp, &fpbuflen))
static int Crypto_SoftClientError(char *data_out, size_t *len_out, const char *msg)
{
*len_out = 0;
- Con_Printf("%s\n", msg);
+ Con_DPrintf("%s\n", msg);
return CRYPTO_DISCARD;
}
if (len_in == 6 && !memcmp(string, "accept", 6) && cls.connect_trying && d0_rijndael_dll)
{
int wantserverid = -1;
- Crypto_RetrieveHostKey(&cls.connect_address, &wantserverid, NULL, 0, NULL, 0, NULL);
+ Crypto_RetrieveHostKey(&cls.connect_address, &wantserverid, NULL, 0, NULL, 0, NULL, NULL);
if(!crypto || !crypto->authenticated) // we ALSO get here if we are using an encrypted connection, so let's rule this out
{
if(wantserverid >= 0)
else if (len_in >= 1 && string[0] == 'j' && cls.connect_trying && d0_rijndael_dll)
{
int wantserverid = -1;
- Crypto_RetrieveHostKey(&cls.connect_address, &wantserverid, NULL, 0, NULL, 0, NULL);
+ Crypto_RetrieveHostKey(&cls.connect_address, &wantserverid, NULL, 0, NULL, 0, NULL, NULL);
//if(!crypto || !crypto->authenticated)
{
if(wantserverid >= 0)
int wantserverid = -1;
// these three are harmless
- if(string[4] == CCREP_SERVER_INFO)
+ if((unsigned char) string[4] == CCREP_SERVER_INFO)
return CRYPTO_NOMATCH;
- if(string[4] == CCREP_PLAYER_INFO)
+ if((unsigned char) string[4] == CCREP_PLAYER_INFO)
return CRYPTO_NOMATCH;
- if(string[4] == CCREP_RULE_INFO)
+ if((unsigned char) string[4] == CCREP_RULE_INFO)
return CRYPTO_NOMATCH;
- Crypto_RetrieveHostKey(&cls.connect_address, &wantserverid, NULL, 0, NULL, 0, NULL);
+ Crypto_RetrieveHostKey(&cls.connect_address, &wantserverid, NULL, 0, NULL, 0, NULL, NULL);
//if(!crypto || !crypto->authenticated)
{
if(wantserverid >= 0)
qboolean server_can_auth = true;
char wantserver_idfp[FP64_SIZE+1];
int wantserver_aeslevel = 0;
+ qboolean wantserver_issigned = false;
+
+ // Must check the source IP here, if we want to prevent other servers' replies from falsely advancing the crypto state, preventing successful connect to the real server.
+ if (net_sourceaddresscheck.integer && LHNETADDRESS_Compare(peeraddress, &cls.connect_address))
+ return Crypto_SoftClientError(data_out, len_out, "challenge message from wrong server");
// if we have a stored host key for the server, assume serverid to already be selected!
// (the loop will refuse to overwrite this one then)
wantserver_idfp[0] = 0;
- Crypto_RetrieveHostKey(&cls.connect_address, &wantserverid, NULL, 0, wantserver_idfp, sizeof(wantserver_idfp), &wantserver_aeslevel);
+ Crypto_RetrieveHostKey(&cls.connect_address, &wantserverid, NULL, 0, wantserver_idfp, sizeof(wantserver_idfp), &wantserver_aeslevel, &wantserver_issigned);
// requirement: wantserver_idfp is a full ID if wantserverid set
// if we leave, we have to consider the connection
GetUntilNul(&data_in, &len_in);
if(!data_in)
return (wantserverid >= 0) ? Crypto_ClientError(data_out, len_out, "Server tried an unauthenticated connection even though a host key is present") :
- (d0_rijndael_dll && crypto_aeslevel.integer >= 3) ? Crypto_ServerError(data_out, len_out, "This server requires encryption to be not required (crypto_aeslevel <= 2)", NULL) :
+ (d0_rijndael_dll && crypto_aeslevel.integer >= 3) ? Crypto_ClientError(data_out, len_out, "This server requires encryption to be not required (crypto_aeslevel <= 2)") :
CRYPTO_NOMATCH;
// FTEQW extension protocol
if(!vlen_blind_id_ptr)
return (wantserverid >= 0) ? Crypto_ClientError(data_out, len_out, "Server tried an unauthenticated connection even though authentication is required") :
- (d0_rijndael_dll && crypto_aeslevel.integer >= 3) ? Crypto_ServerError(data_out, len_out, "This server requires encryption to be not required (crypto_aeslevel <= 2)", NULL) :
+ (d0_rijndael_dll && crypto_aeslevel.integer >= 3) ? Crypto_ClientError(data_out, len_out, "This server requires encryption to be not required (crypto_aeslevel <= 2)") :
CRYPTO_NOMATCH;
data_in = vlen_blind_id_ptr;
crypto->server_keyfp[0] = 0;
crypto->server_idfp[0] = 0;
memcpy(CDATA->wantserver_idfp, wantserver_idfp, sizeof(crypto->server_idfp));
+ CDATA->wantserver_issigned = wantserver_issigned;
if(CDATA->wantserver_idfp[0]) // if we know a host key, honor its encryption setting
switch(bound(0, d0_rijndael_dll ? crypto_aeslevel.integer : 0, 3))
default: // dummy, never happens, but to make gcc happy...
case 0:
if(wantserver_aeslevel >= 3)
- return Crypto_ServerError(data_out, len_out, "This server requires encryption to be not required (crypto_aeslevel <= 2)", NULL);
+ return Crypto_ClientError(data_out, len_out, "This server requires encryption to be not required (crypto_aeslevel <= 2)");
CDATA->wantserver_aes = false;
break;
case 1:
break;
case 3:
if(wantserver_aeslevel <= 0)
- return Crypto_ServerError(data_out, len_out, "This server requires encryption to be supported (crypto_aeslevel >= 1, and d0_rijndael library must be present)", NULL);
+ return Crypto_ClientError(data_out, len_out, "This server requires encryption to be supported (crypto_aeslevel >= 1, and d0_rijndael library must be present)");
CDATA->wantserver_aes = true;
break;
}
// I am the client, and my key is ok... so let's set client_keyfp and client_idfp
strlcpy(crypto->client_keyfp, pubkeys_fp64[CDATA->c], sizeof(crypto->client_keyfp));
strlcpy(crypto->client_idfp, pubkeys_priv_fp64[CDATA->c], sizeof(crypto->client_idfp));
+ crypto->client_issigned = pubkeys_havesig[CDATA->c];
}
if(serverid >= 0)
CDATA->next_step = 1;
*len_out = data_out_p - data_out;
}
- else if(clientid >= 0)
+ else // if(clientid >= 0) // guaranteed by condition one level outside
{
// skip over server auth, perform client auth only
if(!CDATA->id)
data_out_p += *len_out;
*len_out = data_out_p - data_out;
}
- else
- *len_out = data_out_p - data_out;
-
return CRYPTO_DISCARD;
}
else
if(wantserver_idfp[0]) // if we know a host key, honor its encryption setting
if(wantserver_aeslevel >= 3)
return Crypto_ClientError(data_out, len_out, "Server insists on encryption, but neither can authenticate to the other");
- return (d0_rijndael_dll && crypto_aeslevel.integer >= 3) ? Crypto_ServerError(data_out, len_out, "This server requires encryption to be not required (crypto_aeslevel <= 2)", NULL) :
+ return (d0_rijndael_dll && crypto_aeslevel.integer >= 3) ? Crypto_ClientError(data_out, len_out, "This server requires encryption to be not required (crypto_aeslevel <= 2)") :
CRYPTO_NOMATCH;
}
}
{
const char *cnt;
int id;
+
+ // Must check the source IP here, if we want to prevent other servers' replies from falsely advancing the crypto state, preventing successful connect to the real server.
+ if (net_sourceaddresscheck.integer && LHNETADDRESS_Compare(peeraddress, &cls.connect_address))
+ return Crypto_SoftClientError(data_out, len_out, "d0pk\\ message from wrong server");
+
cnt = InfoString_GetValue(string + 4, "id", infostringvalue, sizeof(infostringvalue));
id = (cnt ? atoi(cnt) : -1);
cnt = InfoString_GetValue(string + 4, "cnt", infostringvalue, sizeof(infostringvalue));
{
if(id >= 0)
if(CDATA->cdata_id != id)
- return Crypto_SoftServerError(data_out, len_out, va(vabuf, sizeof(vabuf), "Got d0pk\\id\\%d when expecting %d", id, CDATA->cdata_id));
+ return Crypto_SoftClientError(data_out, len_out, va(vabuf, sizeof(vabuf), "Got d0pk\\id\\%d when expecting %d", id, CDATA->cdata_id));
if(CDATA->next_step != 1)
return Crypto_SoftClientError(data_out, len_out, va(vabuf, sizeof(vabuf), "Got d0pk\\cnt\\%s when expecting %d", cnt, CDATA->next_step));
if(id >= 0)
if(CDATA->cdata_id != id)
- return Crypto_SoftServerError(data_out, len_out, va(vabuf, sizeof(vabuf), "Got d0pk\\id\\%d when expecting %d", id, CDATA->cdata_id));
+ return Crypto_SoftClientError(data_out, len_out, va(vabuf, sizeof(vabuf), "Got d0pk\\id\\%d when expecting %d", id, CDATA->cdata_id));
if(CDATA->next_step != 3)
return Crypto_SoftClientError(data_out, len_out, va(vabuf, sizeof(vabuf), "Got d0pk\\cnt\\%s when expecting %d", cnt, CDATA->next_step));
CLEAR_CDATA;
return Crypto_ClientError(data_out, len_out, "d0_blind_id_authenticate_with_private_id_verify failed (server authentication error)");
}
- if(status)
- strlcpy(crypto->server_keyfp, pubkeys_fp64[CDATA->s], sizeof(crypto->server_keyfp));
- else
- crypto->server_keyfp[0] = 0;
+
+ strlcpy(crypto->server_keyfp, pubkeys_fp64[CDATA->s], sizeof(crypto->server_keyfp));
+ if (!status && CDATA->wantserver_issigned)
+ {
+ CLEAR_CDATA;
+ return Crypto_ClientError(data_out, len_out, "Stored host key requires a valid signature, but server did not provide any");
+ }
+ crypto->server_issigned = status;
+
memset(crypto->server_idfp, 0, sizeof(crypto->server_idfp));
fpbuflen = FP64_SIZE;
if(!qd0_blind_id_fingerprint64_public_id(CDATA->id, crypto->server_idfp, &fpbuflen))
}
// cache the server key
- Crypto_StoreHostKey(&cls.connect_address, va(vabuf, sizeof(vabuf), "%d %s@%s", crypto->use_aes ? 1 : 0, crypto->server_idfp, pubkeys_fp64[CDATA->s]), false);
+ Crypto_StoreHostKey(&cls.connect_address, va(vabuf, sizeof(vabuf), "%d %s@%s%s", crypto->use_aes ? 1 : 0, crypto->server_idfp, crypto->server_issigned ? "" : "~", pubkeys_fp64[CDATA->s]), false);
if(CDATA->c >= 0)
{
if(id >= 0)
if(CDATA->cdata_id != id)
- return Crypto_SoftServerError(data_out, len_out, va(vabuf, sizeof(vabuf), "Got d0pk\\id\\%d when expecting %d", id, CDATA->cdata_id));
+ return Crypto_SoftClientError(data_out, len_out, va(vabuf, sizeof(vabuf), "Got d0pk\\id\\%d when expecting %d", id, CDATA->cdata_id));
if(CDATA->next_step != 5)
return Crypto_SoftClientError(data_out, len_out, va(vabuf, sizeof(vabuf), "Got d0pk\\cnt\\%s when expecting %d", cnt, CDATA->next_step));