diff options
Diffstat (limited to 'openbsc/src/gprs/gtphub.c')
| -rw-r--r-- | openbsc/src/gprs/gtphub.c | 88 |
1 files changed, 66 insertions, 22 deletions
diff --git a/openbsc/src/gprs/gtphub.c b/openbsc/src/gprs/gtphub.c index 389a0cac6..76fe78add 100644 --- a/openbsc/src/gprs/gtphub.c +++ b/openbsc/src/gprs/gtphub.c @@ -368,43 +368,65 @@ static char imsi_digit_to_char(uint8_t nibble) /* Return a human readable IMSI string, in a static buffer. * imsi must point at 8 octets of IMSI IE encoded IMSI data. */ -static const char *imsi_to_str(uint8_t *imsi) +static int imsi_to_str(uint8_t *imsi, const char **imsi_str) { static char str[17]; int i; + char c; for (i = 0; i < 8; i++) { - str[2*i] = imsi_digit_to_char(imsi[i]); - str[2*i + 1] = imsi_digit_to_char(imsi[i] >> 4); + c = imsi_digit_to_char(imsi[i]); + if (c == '?') + return -1; + str[2*i] = c; + + c = imsi_digit_to_char(imsi[i] >> 4); + if (c == '?') + return -1; + str[2*i + 1] = c; } str[16] = '\0'; - return str; + *imsi_str = str; + return 1; } -static const char *get_ie_imsi_str(union gtpie_member *ie[], int i) +/* Return 0 if not present, 1 if present and decoded successfully, -1 if + * present but cannot be decoded. */ +static int get_ie_imsi_str(union gtpie_member *ie[], int i, const char **imsi_str) { uint8_t imsi_buf[8]; if (!get_ie_imsi(ie, i, imsi_buf)) - return NULL; - return imsi_to_str(imsi_buf); + return 0; + return imsi_to_str(imsi_buf, imsi_str); } -static const char *get_ie_apn_str(union gtpie_member *ie[]) +/* Return 0 if not present, 1 if present and decoded successfully, -1 if + * present but cannot be decoded. */ +static int get_ie_apn_str(union gtpie_member *ie[], const char **apn_str) { static char apn_buf[GSM_APN_LENGTH]; unsigned int len; if (gtpie_gettlv(ie, GTPIE_APN, 0, &len, apn_buf, sizeof(apn_buf)) != 0) - return NULL; + return 0; - if (!len) - return NULL; + if (len < 2) { + LOGERR("APN IE: invalid length: %d\n", + (int)len); + return -1; + } if (len > (sizeof(apn_buf) - 1)) len = sizeof(apn_buf) - 1; apn_buf[len] = '\0'; - return gprs_apn_to_str(apn_buf, (uint8_t*)apn_buf, len); + *apn_str = gprs_apn_to_str(apn_buf, (uint8_t*)apn_buf, len); + if (!(*apn_str)) { + LOGERR("APN IE: present but cannot be decoded: %s\n", + osmo_hexdump((uint8_t*)apn_buf, len)); + return -1; + } + return 1; } @@ -445,8 +467,8 @@ static void gtp_decode(const uint8_t *data, int data_len, int i; for (i = 0; i < 10; i++) { - const char *imsi = get_ie_imsi_str(res->ie, i); - if (!imsi) + const char *imsi; + if (get_ie_imsi_str(res->ie, i, &imsi) < 1) break; LOG("| IMSI %s\n", imsi); } @@ -678,8 +700,9 @@ static void gtphub_peer_port_del(struct gtphub_peer_port *pp) /* From the information in the gtp_packet_desc, return the address of a GGSN. * Return -1 on error. */ -static struct gtphub_peer_port *gtphub_resolve_ggsn(struct gtphub *hub, - struct gtp_packet_desc *p); +static int gtphub_resolve_ggsn(struct gtphub *hub, + struct gtp_packet_desc *p, + struct gtphub_peer_port **pp); /* See gtphub_ext.c (wrapped by unit test) */ struct gtphub_peer_port *gtphub_resolve_ggsn_addr(struct gtphub *hub, @@ -1572,7 +1595,8 @@ int gtphub_from_sgsns_handle_buf(struct gtphub *hub, /* See what our GGSN guess would be from the packet data per se. */ /* TODO maybe not do this always? */ struct gtphub_peer_port *ggsn_from_packet; - ggsn_from_packet = gtphub_resolve_ggsn(hub, &p); + if (gtphub_resolve_ggsn(hub, &p, &ggsn_from_packet) < 0) + return -1; if (ggsn_from_packet && ggsn && (ggsn_from_packet != ggsn)) { @@ -1998,12 +2022,32 @@ struct gtphub_peer_port *gtphub_port_have(struct gtphub *hub, return gtphub_addr_add_port(a, port); } -static struct gtphub_peer_port *gtphub_resolve_ggsn(struct gtphub *hub, - struct gtp_packet_desc *p) +/* Return 0 if the message in p is not applicable for GGSN resolution, -1 if + * resolution should be possible but failed, and 1 if resolution was + * successful. *pp will be set to NULL if <1 is returned. */ +static int gtphub_resolve_ggsn(struct gtphub *hub, + struct gtp_packet_desc *p, + struct gtphub_peer_port **pp) { - return gtphub_resolve_ggsn_addr(hub, - get_ie_imsi_str(p->ie, 0), - get_ie_apn_str(p->ie)); + *pp = NULL; + + /* TODO determine from message type whether IEs should be present? */ + + int rc; + const char *imsi_str; + rc = get_ie_imsi_str(p->ie, 0, &imsi_str); + if (rc < 1) + return rc; + OSMO_ASSERT(imsi_str); + + const char *apn_str; + rc = get_ie_apn_str(p->ie, &apn_str); + if (rc < 1) + return rc; + OSMO_ASSERT(apn_str); + + *pp = gtphub_resolve_ggsn_addr(hub, imsi_str, apn_str); + return (*pp)? 1 : -1; } |