chap-secrets: allow to use pool name instead of address to specify ipv4 pool

 Chap-secrets' ipdb uses 4th field as static peer ipv4 address. With no radius
 and multiple same username sessions, it's impossible to use non-default pool
 for such sessions.
 Abuse chap-secret's 4th field as pool=name to specify session's pool name.
 With ippool module loaded after chap-secrets (default order), it will be
 used for allocation from the specified poll name.

 Compatibility considerations:
 * pppd will skip 'pool=*' with warn 'unknown host in auth. address list'
   same as 5th field - shaper, because starting from 4th field pppd
   parse list of value. so, no new effects here.
 * previous versions of accel-ppp will parse 'pool=*' as empty address.
 * with no 'pool=*' in chap-secrets or with no chap-secrets loaded, no
   behavior change.
 * with no ippool loaded, session will get no peer address.
 * with ippool loaded before chap-secrets, chap-secrets's ipdb will not
   be used, therefore neither ip addess not pool name will has no effect.
 * if chap-secrets' pool is invalid or not found, default pool will be
   used by ippool or address came from radius.
 * chap-secret's pool name might override pool came from radius, if
   radius module is loaded after chap-secrets and no address came from
   radius.

1 files changed, 15 insertions, 3 deletions

diff --git a/accel-pppd/extra/chap-secrets.c b/accel-pppd/extra/chap-secrets.c
index f99bd0b..166a619 100644
--- a/accel-pppd/extra/chap-secrets.c
+++ b/accel-pppd/extra/chap-secrets.c
@@ -43,6 +43,7 @@ struct cs_pd_t
 	struct ipv4db_item_t ip;
 	char *passwd;
 	char *rate;
+	char *pool;
 };
 
 #ifdef CRYPTO_OPENSSL
@@ -229,8 +230,12 @@ found:
 	}
 
 	pd->ip.addr = conf_gw_ip_address;
-	if (n >= 3 && ptr[2][0] != '*')
-		pd->ip.peer_addr = inet_addr(ptr[2]);
+	if (n >= 3 && ptr[2][0] != '*') {
+		if (strncmp(ptr[2], "pool=", 5) == 0)
+			pd->pool = _strdup(ptr[2] + 5);
+		else
+			pd->ip.peer_addr = inet_addr(ptr[2]);
+	}
 	pd->ip.mask = conf_netmask;
 	pd->ip.owner = &ipdb;
 
@@ -269,6 +274,8 @@ static void ev_ses_finished(struct ap_session *ses)
 	_free(pd->passwd);
 	if (pd->rate)
 		_free(pd->rate);
+	if (pd->pool)
+		_free(pd->pool);
 	_free(pd);
 }
 
@@ -300,7 +307,12 @@ static struct ipv4db_item_t *get_ip(struct ap_session *ses)
 	if (!pd)
 		return NULL;
 
-	if (!pd->ip.peer_addr)
+	if (pd->pool) {
+		if (ses->ipv4_pool_name)
+			_free(ses->ipv4_pool_name);
+		ses->ipv4_pool_name = _strdup(pd->pool);
+		return NULL;
+	} else if (!pd->ip.peer_addr)
 		return NULL;
 
 	if (!ses->ctrl->ppp)