diff options
Diffstat (limited to 'include/osmocom/sgsn/gb_proxy.h')
-rw-r--r-- | include/osmocom/sgsn/gb_proxy.h | 334 |
1 files changed, 334 insertions, 0 deletions
diff --git a/include/osmocom/sgsn/gb_proxy.h b/include/osmocom/sgsn/gb_proxy.h new file mode 100644 index 000000000..1e8fb253c --- /dev/null +++ b/include/osmocom/sgsn/gb_proxy.h @@ -0,0 +1,334 @@ +#ifndef _GB_PROXY_H +#define _GB_PROXY_H + + +#include <osmocom/core/msgb.h> +#include <osmocom/gsm/gsm23003.h> + +#include <osmocom/gprs/gprs_ns.h> +#include <osmocom/vty/command.h> + +#include <sys/types.h> +#include <regex.h> +#include <stdbool.h> + +#define GBPROXY_INIT_VU_GEN_TX 256 + +struct rate_ctr_group; +struct gprs_gb_parse_context; +struct tlv_parsed; + +enum gbproxy_global_ctr { + GBPROX_GLOB_CTR_INV_BVCI, + GBPROX_GLOB_CTR_INV_LAI, + GBPROX_GLOB_CTR_INV_RAI, + GBPROX_GLOB_CTR_INV_NSEI, + GBPROX_GLOB_CTR_PROTO_ERR_BSS, + GBPROX_GLOB_CTR_PROTO_ERR_SGSN, + GBPROX_GLOB_CTR_NOT_SUPPORTED_BSS, + GBPROX_GLOB_CTR_NOT_SUPPORTED_SGSN, + GBPROX_GLOB_CTR_RESTART_RESET_SGSN, + GBPROX_GLOB_CTR_TX_ERR_SGSN, + GBPROX_GLOB_CTR_OTHER_ERR, + GBPROX_GLOB_CTR_PATCH_PEER_ERR, +}; + +enum gbproxy_peer_ctr { + GBPROX_PEER_CTR_BLOCKED, + GBPROX_PEER_CTR_UNBLOCKED, + GBPROX_PEER_CTR_DROPPED, + GBPROX_PEER_CTR_INV_NSEI, + GBPROX_PEER_CTR_TX_ERR, + GBPROX_PEER_CTR_RAID_PATCHED_BSS, + GBPROX_PEER_CTR_RAID_PATCHED_SGSN, + GBPROX_PEER_CTR_APN_PATCHED, + GBPROX_PEER_CTR_TLLI_PATCHED_BSS, + GBPROX_PEER_CTR_TLLI_PATCHED_SGSN, + GBPROX_PEER_CTR_PTMSI_PATCHED_BSS, + GBPROX_PEER_CTR_PTMSI_PATCHED_SGSN, + GBPROX_PEER_CTR_PATCH_CRYPT_ERR, + GBPROX_PEER_CTR_PATCH_ERR, + GBPROX_PEER_CTR_ATTACH_REQS, + GBPROX_PEER_CTR_ATTACH_REJS, + GBPROX_PEER_CTR_ATTACH_ACKS, + GBPROX_PEER_CTR_ATTACH_COMPLS, + GBPROX_PEER_CTR_RA_UPD_REQS, + GBPROX_PEER_CTR_RA_UPD_REJS, + GBPROX_PEER_CTR_RA_UPD_ACKS, + GBPROX_PEER_CTR_RA_UPD_COMPLS, + GBPROX_PEER_CTR_GMM_STATUS_BSS, + GBPROX_PEER_CTR_GMM_STATUS_SGSN, + GBPROX_PEER_CTR_DETACH_REQS, + GBPROX_PEER_CTR_DETACH_ACKS, + GBPROX_PEER_CTR_PDP_ACT_REQS, + GBPROX_PEER_CTR_PDP_ACT_REJS, + GBPROX_PEER_CTR_PDP_ACT_ACKS, + GBPROX_PEER_CTR_PDP_DEACT_REQS, + GBPROX_PEER_CTR_PDP_DEACT_ACKS, + GBPROX_PEER_CTR_TLLI_UNKNOWN, + GBPROX_PEER_CTR_TLLI_CACHE_SIZE, + GBPROX_PEER_CTR_LAST, +}; + +enum gbproxy_keep_mode { + GBPROX_KEEP_NEVER, /* don't ever keep TLLI/IMSI state of de-registered subscribers */ + GBPROX_KEEP_REATTACH, /* keep if re-attach has been requested by SGSN */ + GBPROX_KEEP_IDENTIFIED, /* keep if we had resolved an IMSI */ + GBPROX_KEEP_ALWAYS, /* always keep */ +}; + +enum gbproxy_match_id { + GBPROX_MATCH_PATCHING, /* match rule on whether or not we should patch */ + GBPROX_MATCH_ROUTING, /* match rule on whether or not we should route (2-SGSN) */ + GBPROX_MATCH_LAST +}; + +struct gbproxy_match { + bool enable; /* is this match enabled? */ + char *re_str; /* regular expression (for IMSI) in string format */ + regex_t re_comp; /* compiled regular expression (for IMSI) */ +}; + +/* global gb-proxy configuration */ +struct gbproxy_config { + /* parsed from config file */ + uint16_t nsip_sgsn_nsei; + + /* NS instance of libosmogb */ + struct gprs_ns_inst *nsi; + + /* Linked list of all Gb peers (except SGSN) */ + struct llist_head bts_peers; + + /* Counter */ + struct rate_ctr_group *ctrg; + + /* MCC/MNC to be patched into RA-ID on the way from BSS to SGSN? */ + struct osmo_plmn_id core_plmn; + + /* APN to be patched into PDP CTX ACT REQ on the way from BSS to SGSN */ + uint8_t* core_apn; + size_t core_apn_size; + + /* Frequency (sec) at which timer to clean stale links is fired (0 disabled) */ + unsigned int clean_stale_timer_freq; + /* If !0, Max age to consider a struct gbproxy_link_info as stale */ + int tlli_max_age; + /* If !0, Max len of gbproxy_peer->list (list of struct gbproxy_link_info) */ + int tlli_max_len; + /* If !0, Max len of gbproxy_link_info->stored_msgs (list of msgb) */ + uint32_t stored_msgs_max_len; + + /* Should the P-TMSI be patched on the fly (required for 2-SGSN config) */ + bool patch_ptmsi; + /* Should the IMSI be acquired by the proxy (required for 2-SGSN config) */ + bool acquire_imsi; + /* Should we route subscribers to two different SGSNs? */ + bool route_to_sgsn2; + /* NSEI of the second SGSN */ + uint16_t nsip_sgsn2_nsei; + /* should we keep a cache of per-subscriber state even after de-registration? */ + enum gbproxy_keep_mode keep_link_infos; + + /* IMSI checking/matching for 2-SGSN routing and patching */ + struct gbproxy_match matches[GBPROX_MATCH_LAST]; +}; + +struct gbproxy_patch_state { + struct osmo_plmn_id local_plmn; + + /* List of TLLIs for which patching is enabled */ + struct llist_head logical_links; + int logical_link_count; +}; + +/* one peer at NS level that we interact with (BSS/PCU) */ +struct gbproxy_peer { + /* linked to gbproxy_config.bts_peers */ + struct llist_head list; + + /* point back to the config */ + struct gbproxy_config *cfg; + + /* NSEI of the peer entity */ + uint16_t nsei; + + /* BVCI used for Point-to-Point to this peer */ + uint16_t bvci; + bool blocked; + + /* Routeing Area that this peer is part of (raw 04.08 encoding) */ + uint8_t ra[6]; + + /* Counter */ + struct rate_ctr_group *ctrg; + + /* State related to on-the-fly patching of certain messages */ + struct gbproxy_patch_state patch_state; + + /* Fired periodically to clean up stale links from list */ + struct osmo_timer_list clean_stale_timer; +}; + +struct gbproxy_tlli_state { + /* currently active TLLI */ + uint32_t current; + /* newly-assigned TLLI (e.g. during P-TMSI allocation procedure) */ + uint32_t assigned; + /* has the BSS side validated (confirmed) the new TLLI? */ + bool bss_validated; + /* has the SGSN side validated (confirmed) the new TLLI? */ + bool net_validated; + /* NOTE: once both are validated, we set current = assigned and assigned = 0 */ + + /* The P-TMSI for this subscriber */ + uint32_t ptmsi; +}; + +/* One TLLI (= UE, = Subscriber) served via this proxy */ +struct gbproxy_link_info { + /* link to gbproxy_peer.patch_state.logical_links */ + struct llist_head list; + + /* TLLI on the BSS/PCU side */ + struct gbproxy_tlli_state tlli; + /* TLLI on the SGSN side (can be different in case of P-TMSI patching) */ + struct gbproxy_tlli_state sgsn_tlli; + /* NSEI of the SGSN serving this link */ + uint32_t sgsn_nsei; + + /* timestamp when we last had any contact with this UE */ + time_t timestamp; + + /* IMSI of the subscriber (if/once known) */ + uint8_t *imsi; + size_t imsi_len; + + /* is the IMSI acquisition still pending? */ + bool imsi_acq_pending; + + /* queue of stored UL messages (until IMSI acquisition completes and we can + * determine which of the SGSNs we should route this to */ + struct llist_head stored_msgs; + uint32_t stored_msgs_len; + + /* generated N(U) we use (required due to IMSI acquisition */ + unsigned vu_gen_tx_bss; + + /* is this subscriber deregistered (TLLI invalidated)? */ + bool is_deregistered; + + /* does this link match either the (2-SGSN) routing or the patching rule? */ + bool is_matching[GBPROX_MATCH_LAST]; +}; + + +/* gb_proxy_vty .c */ + +int gbproxy_vty_init(void); +int gbproxy_parse_config(const char *config_file, struct gbproxy_config *cfg); + +/* gb_proxy_ctrl.c */ +int gb_ctrl_cmds_install(void); + + +/* gb_proxy.c */ +int gbproxy_init_config(struct gbproxy_config *cfg); + +/* Main input function for Gb proxy */ +int gbprox_rcvmsg(struct gbproxy_config *cfg, struct msgb *msg, uint16_t nsei, uint16_t ns_bvci, uint16_t nsvci); + +int gbprox_signal(unsigned int subsys, unsigned int signal, + void *handler_data, void *signal_data); + +/* Reset all persistent NS-VC's */ +int gbprox_reset_persistent_nsvcs(struct gprs_ns_inst *nsi); + +void gbprox_reset(struct gbproxy_config *cfg); + +/* TLLI info handling */ +void gbproxy_delete_link_infos(struct gbproxy_peer *peer); +struct gbproxy_link_info *gbproxy_update_link_state_ul( + struct gbproxy_peer *peer, time_t now, + struct gprs_gb_parse_context *parse_ctx); +struct gbproxy_link_info *gbproxy_update_link_state_dl( + struct gbproxy_peer *peer, time_t now, + struct gprs_gb_parse_context *parse_ctx); +int gbproxy_update_link_state_after( + struct gbproxy_peer *peer, struct gbproxy_link_info *link_info, + time_t now, struct gprs_gb_parse_context *parse_ctx); +int gbproxy_remove_stale_link_infos(struct gbproxy_peer *peer, time_t now); +void gbproxy_delete_link_info(struct gbproxy_peer *peer, + struct gbproxy_link_info *link_info); +void gbproxy_link_info_discard_messages(struct gbproxy_link_info *link_info); + +void gbproxy_attach_link_info(struct gbproxy_peer *peer, time_t now, + struct gbproxy_link_info *link_info); +void gbproxy_update_link_info(struct gbproxy_link_info *link_info, + const uint8_t *imsi, size_t imsi_len); +void gbproxy_detach_link_info(struct gbproxy_peer *peer, + struct gbproxy_link_info *link_info); +struct gbproxy_link_info *gbproxy_link_info_alloc( struct gbproxy_peer *peer); + +struct gbproxy_link_info *gbproxy_link_info_by_tlli( + struct gbproxy_peer *peer, uint32_t tlli); +struct gbproxy_link_info *gbproxy_link_info_by_imsi( + struct gbproxy_peer *peer, const uint8_t *imsi, size_t imsi_len); +struct gbproxy_link_info *gbproxy_link_info_by_any_sgsn_tlli( + struct gbproxy_peer *peer, uint32_t tlli); +struct gbproxy_link_info *gbproxy_link_info_by_sgsn_tlli( + struct gbproxy_peer *peer, + uint32_t tlli, uint32_t sgsn_nsei); +struct gbproxy_link_info *gbproxy_link_info_by_ptmsi( + struct gbproxy_peer *peer, + uint32_t ptmsi); + +int gbproxy_imsi_matches( + struct gbproxy_config *cfg, + enum gbproxy_match_id match_id, + struct gbproxy_link_info *link_info); +uint32_t gbproxy_map_tlli( + uint32_t other_tlli, struct gbproxy_link_info *link_info, int to_bss); + +/* needed by gb_proxy_tlli.h */ +uint32_t gbproxy_make_bss_ptmsi(struct gbproxy_peer *peer, uint32_t sgsn_ptmsi); +uint32_t gbproxy_make_sgsn_tlli( + struct gbproxy_peer *peer, struct gbproxy_link_info *link_info, + uint32_t bss_tlli); +void gbproxy_reset_link(struct gbproxy_link_info *link_info); +int gbproxy_check_imsi( + struct gbproxy_match *match, const uint8_t *imsi, size_t imsi_len); + +/* Message patching */ +void gbproxy_patch_bssgp( + struct msgb *msg, uint8_t *bssgp, size_t bssgp_len, + struct gbproxy_peer *peer, struct gbproxy_link_info *link_info, + int *len_change, struct gprs_gb_parse_context *parse_ctx); + +int gbproxy_patch_llc( + struct msgb *msg, uint8_t *llc, size_t llc_len, + struct gbproxy_peer *peer, struct gbproxy_link_info *link_info, + int *len_change, struct gprs_gb_parse_context *parse_ctx); + +int gbproxy_set_patch_filter( + struct gbproxy_match *match, const char *filter, const char **err_msg); +void gbproxy_clear_patch_filter(struct gbproxy_match *match); + +/* Peer handling */ +struct gbproxy_peer *gbproxy_peer_by_bvci( + struct gbproxy_config *cfg, uint16_t bvci); +struct gbproxy_peer *gbproxy_peer_by_nsei( + struct gbproxy_config *cfg, uint16_t nsei); +struct gbproxy_peer *gbproxy_peer_by_rai( + struct gbproxy_config *cfg, const uint8_t *ra); +struct gbproxy_peer *gbproxy_peer_by_lai( + struct gbproxy_config *cfg, const uint8_t *la); +struct gbproxy_peer *gbproxy_peer_by_lac( + struct gbproxy_config *cfg, const uint8_t *la); +struct gbproxy_peer *gbproxy_peer_by_bssgp_tlv( + struct gbproxy_config *cfg, struct tlv_parsed *tp); +struct gbproxy_peer *gbproxy_peer_alloc(struct gbproxy_config *cfg, uint16_t bvci); +void gbproxy_peer_free(struct gbproxy_peer *peer); +int gbproxy_cleanup_peers(struct gbproxy_config *cfg, uint16_t nsei, uint16_t bvci); + +#endif |