Avoid a possible buffer overflow in processpap
[l2tpns.git] / radius.c
index 735ae07..ff52cdc 100644 (file)
--- a/radius.c
+++ b/radius.c
@@ -1,6 +1,6 @@
 // L2TPNS Radius Stuff
 
-char const *cvs_id_radius = "$Id: radius.c,v 1.19 2004/11/30 06:50:26 bodea Exp $";
+char const *cvs_id_radius = "$Id: radius.c,v 1.22 2005/01/05 14:35:01 bodea Exp $";
 
 #include <time.h>
 #include <stdio.h>
@@ -21,23 +21,10 @@ char const *cvs_id_radius = "$Id: radius.c,v 1.19 2004/11/30 06:50:26 bodea Exp
 extern radiust *radius;
 extern sessiont *session;
 extern tunnelt *tunnel;
-extern u32 sessionid;
 extern configt *config;
 extern int *radfds;
 extern ip_filtert *ip_filters;
 
-static const char *radius_state(int state)
-{
-       static char *tmp = NULL;
-       int i;
-       for (i = 0; radius_states[i]; i++)
-               if (i == state) return radius_states[i];
-
-       if (tmp == NULL) tmp = (char *)calloc(64, 1);
-       sprintf(tmp, "%d", state);
-       return tmp;
-}
-
 // Set up socket for radius requests
 void initrad(void)
 {
@@ -53,17 +40,16 @@ void initrad(void)
        }
 }
 
-void radiusclear(u16 r, sessionidt s)
+void radiusclear(uint16_t r, sessionidt s)
 {
        if (s) session[s].radius = 0;
        memset(&radius[r], 0, sizeof(radius[r])); // radius[r].state = RADIUSNULL;
 }
 
-
-static u16 get_free_radius()
+static uint16_t get_free_radius()
 {
        int count;
-       static u32 next_radius_id = 0;
+       static uint32_t next_radius_id = 0;
 
        for (count = MAXRADIUS; count > 0 ; --count)
        {
@@ -81,9 +67,9 @@ static u16 get_free_radius()
        return 0;
 }
 
-u16 radiusnew(sessionidt s)
+uint16_t radiusnew(sessionidt s)
 {
-       u16 r = session[s].radius;
+       uint16_t r = session[s].radius;
 
        /* re-use */
        if (r)
@@ -110,16 +96,16 @@ u16 radiusnew(sessionidt s)
 }
 
 // Send a RADIUS request
-void radiussend(u16 r, u8 state)
+void radiussend(uint16_t r, uint8_t state)
 {
        struct sockaddr_in addr;
-       u8 b[4096];            // RADIUS packet
+       uint8_t b[4096];            // RADIUS packet
        char pass[129];
        int pl;
-       u8 *p;
+       uint8_t *p;
        sessionidt s;
 
-       CSTAT(call_radiussend);
+       CSTAT(radiussend);
 
        s = radius[r].session;
        if (!config->numradiusservers)
@@ -142,6 +128,7 @@ void radiussend(u16 r, u8 state)
 
        if (radius[r].state != state)
                radius[r].try = 0;
+
        radius[r].state = state;
        radius[r].retry = backoff(radius[r].try++);
        LOG(4, s, session[s].tunnel, "Send RADIUS id %d sock %d state %s try %d\n",
@@ -157,7 +144,7 @@ void radiussend(u16 r, u8 state)
                        else
                        {
                                LOG(1, s, session[s].tunnel, "RADIUS timeout, but in state %s so don't timeout session\n",
-                                       radius_states[state]);
+                                       radius_state(state));
                                radiusclear(r, s);
                        }
                        STAT(radius_timeout);
@@ -168,7 +155,7 @@ void radiussend(u16 r, u8 state)
                        radius[r].state = RADIUSWAIT;
                        radius[r].retry = 100;
                }
-               return ;
+               return;
        }
        // contruct RADIUS access request
        switch (state)
@@ -246,7 +233,7 @@ void radiussend(u16 r, u8 state)
        {                          // accounting
                *p = 40;                // accounting type
                p[1] = 6;
-               *(u32 *) (p + 2) = htonl((state == RADIUSSTART) ? 1 : 2);
+               *(uint32_t *) (p + 2) = htonl((state == RADIUSSTART) ? 1 : 2);
                p += p[1];
                if (s)
                {
@@ -258,30 +245,30 @@ void radiussend(u16 r, u8 state)
                        {                // stop
                                *p = 42;      // input octets
                                p[1] = 6;
-                               *(u32 *) (p + 2) = htonl(session[s].cin);
+                               *(uint32_t *) (p + 2) = htonl(session[s].cin);
                                p += p[1];
                                *p = 43;      // output octets
                                p[1] = 6;
-                               *(u32 *) (p + 2) = htonl(session[s].cout);
+                               *(uint32_t *) (p + 2) = htonl(session[s].cout);
                                p += p[1];
                                *p = 46;      // session time
                                p[1] = 6;
-                               *(u32 *) (p + 2) = htonl(time(NULL) - session[s].opened);
+                               *(uint32_t *) (p + 2) = htonl(time(NULL) - session[s].opened);
                                p += p[1];
                                *p = 47;      // input packets
                                p[1] = 6;
-                               *(u32 *) (p + 2) = htonl(session[s].pin);
+                               *(uint32_t *) (p + 2) = htonl(session[s].pin);
                                p += p[1];
                                *p = 48;      // output spackets
                                p[1] = 6;
-                               *(u32 *) (p + 2) = htonl(session[s].pout);
+                               *(uint32_t *) (p + 2) = htonl(session[s].pout);
                                p += p[1];
                        }
                        else
                        {                // start
                                *p = 41;      // delay
                                p[1] = 6;
-                               *(u32 *) (p + 2) = htonl(time(NULL) - session[s].opened);
+                               *(uint32_t *) (p + 2) = htonl(time(NULL) - session[s].opened);
                                p += p[1];
                        }
                }
@@ -290,14 +277,14 @@ void radiussend(u16 r, u8 state)
        {
                *p = 5; // NAS-Port
                p[1] = 6;
-               *(u32 *) (p + 2) = htonl(s);
+               *(uint32_t *) (p + 2) = htonl(s);
                p += p[1];
        }
        if (s && session[s].ip)
        {
                *p = 8;                 // Framed-IP-Address
                p[1] = 6;
-               *(u32 *) (p + 2) = htonl(session[s].ip);
+               *(uint32_t *) (p + 2) = htonl(session[s].ip);
                p += p[1];
        }
        if (*session[s].called)
@@ -324,11 +311,11 @@ void radiussend(u16 r, u8 state)
        // NAS-IP-Address
        *p = 4;
        p[1] = 6;
-       *(u32 *)(p + 2) = config->bind_address;
+       *(uint32_t *)(p + 2) = config->bind_address;
        p += p[1];
 
        // All AVpairs added
-       *(u16 *) (b + 2) = htons(p - b);
+       *(uint16_t *) (b + 2) = htons(p - b);
        if (state != RADIUSAUTH)
        {
            // Build auth for accounting packet
@@ -346,14 +333,12 @@ void radiussend(u16 r, u8 state)
        }
        memset(&addr, 0, sizeof(addr));
        addr.sin_family = AF_INET;
-       *(u32 *) & addr.sin_addr = config->radiusserver[(radius[r].try - 1) % config->numradiusservers];
+       *(uint32_t *) & addr.sin_addr = config->radiusserver[(radius[r].try - 1) % config->numradiusservers];
        {
-           // get radius port
-           u16 port = config->radiusport[(radius[r].try - 1) % config->numradiusservers];
-           // no need to define the accounting port for itself:
-           //  the accounting port is as far as I know always one more
-           //  than the auth port    JK 20040713
-           addr.sin_port = htons((state == RADIUSAUTH) ? port : port+1);
+               // get radius port
+               uint16_t port = config->radiusport[(radius[r].try - 1) % config->numradiusservers];
+               // assume RADIUS accounting port is the authentication port +1
+               addr.sin_port = htons((state == RADIUSAUTH) ? port : port+1);
        }
 
        LOG_HEX(5, "RADIUS Send", b, (p - b));
@@ -361,35 +346,36 @@ void radiussend(u16 r, u8 state)
 }
 
 // process RADIUS response
-void processrad(u8 *buf, int len, char socket_index)
+void processrad(uint8_t *buf, int len, char socket_index)
 {
-       u8 b[MAXCONTROL];
+       uint8_t b[MAXCONTROL];
        MD5_CTX ctx;
-       u16 r;
+       uint16_t r;
        sessionidt s;
        tunnelidt t = 0;
        hasht hash;
-       u8 routes = 0;
+       uint8_t routes = 0;
+       int r_code;
+       int r_id;
 
-       int r_code, r_id ; // Radius code.
-
-       r_code = buf[0]; // First byte in radius packet.
-       r_id = buf[1]; // radius reply indentifier.
-
-
-       CSTAT(call_processrad);
+       CSTAT(processrad);
 
        LOG_HEX(5, "RADIUS Response", buf, len);
-       if (len < 20 || len < ntohs(*(u16 *) (buf + 2)))
+       if (len < 20 || len < ntohs(*(uint16_t *) (buf + 2)))
        {
                LOG(1, 0, 0, "Duff RADIUS response length %d\n", len);
                return ;
        }
-       len = ntohs(*(u16 *) (buf + 2));
+
+       r_code = buf[0]; // response type
+       r_id = buf[1]; // radius reply indentifier.
+
+       len = ntohs(*(uint16_t *) (buf + 2));
        r = socket_index | (r_id << RADIUS_SHIFT);
        s = radius[r].session;
-       LOG(3, s, session[s].tunnel, "Received %s, radius %d response for session %u (code %d, id %d)\n",
-                       radius_states[radius[r].state], r, s, r_code, r_id);
+       LOG(3, s, session[s].tunnel, "Received %s, radius %d response for session %u (%s, id %d)\n",
+                       radius_state(radius[r].state), r, s, radius_code(r_code), r_id);
+
        if (!s && radius[r].state != RADIUSSTOP)
        {
                LOG(1, s, session[s].tunnel, "   Unexpected RADIUS response\n");
@@ -413,71 +399,74 @@ void processrad(u8 *buf, int len, char socket_index)
                        LOG(0, s, session[s].tunnel, "   Incorrect auth on RADIUS response!! (wrong secret in radius config?)\n");
                        return; // Do nothing. On timeout, it will try the next radius server.
                }
-               if ((radius[r].state == RADIUSAUTH && *buf != 2 && *buf != 3) ||
-                       ((radius[r].state == RADIUSSTART || radius[r].state == RADIUSSTOP) && *buf != 5))
+
+               if ((radius[r].state == RADIUSAUTH && r_code != AccessAccept && r_code != AccessReject) ||
+                       ((radius[r].state == RADIUSSTART || radius[r].state == RADIUSSTOP) && r_code != AccountingResponse))
                {
-                       LOG(1, s, session[s].tunnel, "   Unexpected RADIUS response %d\n", *buf);
+                       LOG(1, s, session[s].tunnel, "   Unexpected RADIUS response %s\n", radius_code(r_code));
                        return; // We got something we didn't expect. Let the timeouts take
                                // care off finishing the radius session if that's really correct.
                }
+
                if (radius[r].state == RADIUSAUTH)
                {
-                       LOG(4, s, session[s].tunnel, "   Original response is \"%s\"\n", (*buf == 2) ? "accept" : "reject");
+                       // run post-auth plugin
+                       struct param_post_auth packet = {
+                               &tunnel[t],
+                               &session[s],
+                               session[s].user,
+                               (r_code == AccessAccept),
+                               radius[r].chap ? PPPCHAP : PPPPAP
+                       };
+
+                       run_plugins(PLUGIN_POST_AUTH, &packet);
+                       r_code = packet.auth_allowed ? AccessAccept : AccessReject;
+
                        // process auth response
                        if (radius[r].chap)
                        {
                                // CHAP
-                               u8 *p = makeppp(b, sizeof(b), 0, 0, t, s, PPPCHAP);
+                               uint8_t *p = makeppp(b, sizeof(b), 0, 0, t, s, PPPCHAP);
                                if (!p) return; // Abort!
 
-                               {
-                                       struct param_post_auth packet = { &tunnel[t], &session[s], session[s].user, (*buf == 2), PPPCHAP };
-                                       run_plugins(PLUGIN_POST_AUTH, &packet);
-                                       *buf = packet.auth_allowed ? 2 : 3;
-                               }
-
-                               LOG(3, s, session[s].tunnel, "   CHAP User %s authentication %s.\n", session[s].user,
-                                               (*buf == 2) ? "allowed" : "denied");
-                               *p = (*buf == 2) ? 3 : 4;     // ack/nak
+                               *p = (r_code == AccessAccept) ? 3 : 4;     // ack/nak
                                p[1] = radius[r].id;
-                               *(u16 *) (p + 2) = ntohs(4); // no message
+                               *(uint16_t *) (p + 2) = ntohs(4); // no message
                                tunnelsend(b, (p - b) + 4, t); // send it
+
+                               LOG(3, s, session[s].tunnel, "   CHAP User %s authentication %s.\n", session[s].user,
+                                               (r_code == AccessAccept) ? "allowed" : "denied");
                        }
                        else
                        {
                                // PAP
-                               u8 *p = makeppp(b, sizeof(b), 0, 0, t, s, PPPPAP);
+                               uint8_t *p = makeppp(b, sizeof(b), 0, 0, t, s, PPPPAP);
                                if (!p) return;         // Abort!
 
-                               {
-                                       struct param_post_auth packet = { &tunnel[t], &session[s], session[s].user, (*buf == 2), PPPPAP };
-                                       run_plugins(PLUGIN_POST_AUTH, &packet);
-                                       *buf = packet.auth_allowed ? 2 : 3;
-                               }
-
-                               LOG(3, s, session[s].tunnel, "   PAP User %s authentication %s.\n", session[s].user,
-                                               (*buf == 2) ? "allowed" : "denied");
                                // ack/nak
-                               *p = *buf;
+                               *p = r_code;
                                p[1] = radius[r].id;
-                               *(u16 *) (p + 2) = ntohs(5);
+                               *(uint16_t *) (p + 2) = ntohs(5);
                                p[4] = 0; // no message
                                tunnelsend(b, (p - b) + 5, t); // send it
+
+                               LOG(3, s, session[s].tunnel, "   PAP User %s authentication %s.\n", session[s].user,
+                                               (r_code == AccessAccept) ? "allowed" : "denied");
                        }
 
-                       if (*buf == 2)
+                       if (r_code == AccessAccept)
                        {
                                // Login successful
                                // Extract IP, routes, etc
-                               u8 *p = buf + 20;
-                               u8 *e = buf + len;
+                               uint8_t *p = buf + 20;
+                               uint8_t *e = buf + len;
                                for (; p + 2 <= e && p[1] && p + p[1] <= e; p += p[1])
                                {
                                        if (*p == 8)
                                        {
                                                // Framed-IP-Address
                                                if (p[1] < 6) continue;
-                                               session[s].ip = ntohl(*(u32 *) (p + 2));
+                                               session[s].ip = ntohl(*(uint32_t *) (p + 2));
                                                session[s].ip_pool_index = -1;
                                                LOG(3, s, session[s].tunnel, "   Radius reply contains IP address %s\n",
                                                        fmtaddr(htonl(session[s].ip), 0));
@@ -486,7 +475,7 @@ void processrad(u8 *buf, int len, char socket_index)
                                        {
                                                // DNS address
                                                if (p[1] < 6) continue;
-                                               session[s].dns1 = ntohl(*(u32 *) (p + 2));
+                                               session[s].dns1 = ntohl(*(uint32_t *) (p + 2));
                                                LOG(3, s, session[s].tunnel, "   Radius reply contains primary DNS address %s\n",
                                                        fmtaddr(htonl(session[s].dns1), 0));
                                        }
@@ -494,18 +483,18 @@ void processrad(u8 *buf, int len, char socket_index)
                                        {
                                                // DNS address
                                                if (p[1] < 6) continue;
-                                               session[s].dns2 = ntohl(*(u32 *) (p + 2));
+                                               session[s].dns2 = ntohl(*(uint32_t *) (p + 2));
                                                LOG(3, s, session[s].tunnel, "   Radius reply contains secondary DNS address %s\n",
                                                        fmtaddr(htonl(session[s].dns2), 0));
                                        }
                                        else if (*p == 22)
                                        {
                                                // Framed-Route
-                                               ipt ip = 0, mask = 0;
-                                               u8 u = 0;
-                                               u8 bits = 0;
-                                               u8 *n = p + 2;
-                                               u8 *e = p + p[1];
+                                               in_addr_t ip = 0, mask = 0;
+                                               uint8_t u = 0;
+                                               uint8_t bits = 0;
+                                               uint8_t *n = p + 2;
+                                               uint8_t *e = p + p[1];
                                                while (n < e && (isdigit(*n) || *n == '.'))
                                                {
                                                        if (*n == '.')
@@ -552,7 +541,7 @@ void processrad(u8 *buf, int len, char socket_index)
                                                char *filter = p + 2;
                                                int l = p[1] - 2;
                                                char *suffix;
-                                               u8 *f = 0;
+                                               uint8_t *f = 0;
                                                int i;
 
                                                LOG(3, s, session[s].tunnel, "   Radius reply contains Filter-Id \"%.*s\"\n", l, filter);
@@ -632,7 +621,7 @@ void processrad(u8 *buf, int len, char socket_index)
                                        }
                                }
                        }
-                       else if (*buf == 3)
+                       else if (r_code == AccessReject)
                        {
                                LOG(2, s, session[s].tunnel, "   Authentication denied for %s\n", session[s].user);
 //FIXME: We should tear down the session here!
@@ -657,7 +646,7 @@ void processrad(u8 *buf, int len, char socket_index)
                else
                {
                                // An ack for a stop or start record.
-                       LOG(3, s, t, "   RADIUS accounting ack recv in state %s\n", radius_states[radius[r].state]);
+                       LOG(3, s, t, "   RADIUS accounting ack recv in state %s\n", radius_state(radius[r].state));
                        break;
                }
        } while (0);
@@ -667,15 +656,15 @@ void processrad(u8 *buf, int len, char socket_index)
 }
 
 // Send a retry for RADIUS/CHAP message
-void radiusretry(u16 r)
+void radiusretry(uint16_t r)
 {
        sessionidt s = radius[r].session;
        tunnelidt t = 0;
 
-       CSTAT(call_radiusretry);
+       CSTAT(radiusretry);
+
+       if (s) t = session[s].tunnel;
 
-       if (s)
-               t = session[s].tunnel;
        radius[r].retry = backoff(radius[r].try + 1);
        switch (radius[r].state)
        {