diff options
| -rw-r--r-- | openbsc/src/ipaccess/ipaccess-proxy.c | 47 |
1 files changed, 46 insertions, 1 deletions
diff --git a/openbsc/src/ipaccess/ipaccess-proxy.c b/openbsc/src/ipaccess/ipaccess-proxy.c index 3f1005c92..3e1bcdc34 100644 --- a/openbsc/src/ipaccess/ipaccess-proxy.c +++ b/openbsc/src/ipaccess/ipaccess-proxy.c @@ -61,6 +61,7 @@ struct ipa_proxy { struct timer_list reconn_timer; /* global GPRS NS data */ struct in_addr gprs_addr; + struct in_addr listen_addr; }; /* global pointer to the proxy structure */ @@ -101,6 +102,8 @@ struct ipa_bts_conn { struct in_addr bts_addr; struct bsc_fd gprs_ns_fd; int gprs_local_port; + uint16_t gprs_orig_port; + uint32_t gprs_orig_ip; char *id_tags[0xff]; u_int8_t *id_resp; @@ -846,6 +849,44 @@ static void handle_dead_socket(struct bsc_fd *bfd) talloc_free(ipc); } +static void patch_gprs_msg(struct ipa_bts_conn *ipbc, int priv_nr, struct msgb *msg) +{ + uint8_t *nsvci; + + if ((priv_nr & 0xff) != OML_FROM_BTS && (priv_nr & 0xff) != OML_TO_BSC) + return; + + if (msgb_l2len(msg) != 39) + return; + + /* + * Check if this is a IPA Set Attribute or IPA Set Attribute ACK + * and if the FOM Class is GPRS NSVC0 and then we will patch it. + * + * The patch assumes the message looks like the one from the trace + * but we only match messages with a specific size anyway... So + * this hack should work just fine. + */ + + if (msg->l2h[0] == 0x10 && msg->l2h[1] == 0x80 && + msg->l2h[2] == 0x00 && msg->l2h[3] == 0x15 && + msg->l2h[18] == 0xf5 && msg->l2h[19] == 0xf2) { + printf("found GPRS NSVC SET foo...\n"); + nsvci = &msg->l2h[23]; + ipbc->gprs_orig_port = *(u_int16_t *)(nsvci+8); + ipbc->gprs_orig_ip = *(u_int32_t *)(nsvci+10); + *(u_int16_t *)(nsvci+8) = htons(ipbc->gprs_local_port); + *(u_int32_t *)(nsvci+10) = ipbc->ipp->listen_addr.s_addr; + } else if (msg->l2h[0] == 0x10 && msg->l2h[1] == 0x80 && + msg->l2h[2] == 0x00 && msg->l2h[3] == 0x15 && + msg->l2h[18] == 0xf6 && msg->l2h[19] == 0xf2) { + printf("found GPRS NSVC SET ACK...\n"); + nsvci = &msg->l2h[23]; + *(u_int16_t *)(nsvci+8) = ipbc->gprs_orig_port; + *(u_int32_t *)(nsvci+10) = ipbc->gprs_orig_ip; + } +} + static int handle_tcp_read(struct bsc_fd *bfd) { struct ipa_proxy_conn *ipc = bfd->data; @@ -903,6 +944,8 @@ static int handle_tcp_read(struct bsc_fd *bfd) bsc_conn = ipc_by_priv_nr(ipbc, bfd->priv_nr); if (bsc_conn) { + if (gprs_ns_ipaddr) + patch_gprs_msg(ipbc, bfd->priv_nr, msg); /* enqueue packet towards BSC */ msgb_enqueue(&bsc_conn->tx_queue, msg); /* mark respective filedescriptor as 'we want to write' */ @@ -1210,8 +1253,10 @@ static int ipaccess_proxy_setup(void) return ret; /* Connect the GPRS NS Socket */ - if (gprs_ns_ipaddr) + if (gprs_ns_ipaddr) { inet_aton(gprs_ns_ipaddr, &ipp->gprs_addr); + inet_aton(listen_ipaddr, &ipp->listen_addr); + } return ret; } |