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Diffstat (limited to 'openbsc/src/osmo-bsc_nat/bsc_nat_utils.c')
-rw-r--r--openbsc/src/osmo-bsc_nat/bsc_nat_utils.c589
1 files changed, 0 insertions, 589 deletions
diff --git a/openbsc/src/osmo-bsc_nat/bsc_nat_utils.c b/openbsc/src/osmo-bsc_nat/bsc_nat_utils.c
index 96b937c2b..c1c233bfa 100644
--- a/openbsc/src/osmo-bsc_nat/bsc_nat_utils.c
+++ b/openbsc/src/osmo-bsc_nat/bsc_nat_utils.c
@@ -782,592 +782,3 @@ int bsc_write_cb(struct osmo_fd *bfd, struct msgb *msg)
return rc;
}
-static char *match_and_rewrite_number(void *ctx, const char *number,
- const char *imsi,
- struct llist_head *list)
-{
- struct bsc_nat_num_rewr_entry *entry;
- char *new_number = NULL;
-
- /* need to find a replacement and then fix it */
- llist_for_each_entry(entry, list, list) {
- regmatch_t matches[2];
-
- /* check the IMSI match */
- if (regexec(&entry->msisdn_reg, imsi, 0, NULL, 0) != 0)
- continue;
-
- /* this regexp matches... */
- if (regexec(&entry->num_reg, number, 2, matches, 0) == 0 &&
- matches[1].rm_eo != -1)
- new_number = talloc_asprintf(ctx, "%s%s",
- entry->replace,
- &number[matches[1].rm_so]);
- if (new_number)
- break;
- }
-
- return new_number;
-}
-
-static char *rewrite_non_international(struct bsc_nat *nat, void *ctx, const char *imsi,
- struct gsm_mncc_number *called)
-{
- if (llist_empty(&nat->num_rewr))
- return NULL;
-
- if (called->plan != 1)
- return NULL;
- if (called->type == 1)
- return NULL;
-
- return match_and_rewrite_number(ctx, called->number,
- imsi, &nat->num_rewr);
-}
-
-
-/**
- * Rewrite non global numbers... according to rules based on the IMSI
- */
-static struct msgb *rewrite_setup(struct bsc_nat *nat, struct msgb *msg,
- struct bsc_nat_parsed *parsed, const char *imsi,
- struct gsm48_hdr *hdr48, const uint32_t len)
-{
- struct tlv_parsed tp;
- unsigned int payload_len;
- struct gsm_mncc_number called;
- struct msgb *out;
- char *new_number = NULL;
- uint8_t *outptr;
- const uint8_t *msgptr;
- int sec_len;
-
- /* decode and rewrite the message */
- payload_len = len - sizeof(*hdr48);
- tlv_parse(&tp, &gsm48_att_tlvdef, hdr48->data, payload_len, 0, 0);
-
- /* no number, well let us ignore it */
- if (!TLVP_PRESENT(&tp, GSM48_IE_CALLED_BCD))
- return NULL;
-
- memset(&called, 0, sizeof(called));
- gsm48_decode_called(&called,
- TLVP_VAL(&tp, GSM48_IE_CALLED_BCD) - 1);
-
- /* check if it looks international and stop */
- new_number = rewrite_non_international(nat, msg, imsi, &called);
-
- if (!new_number) {
- LOGP(DNAT, LOGL_DEBUG, "No IMSI match found, returning message.\n");
- return NULL;
- }
-
- if (strlen(new_number) > sizeof(called.number)) {
- LOGP(DNAT, LOGL_ERROR, "Number is too long for structure.\n");
- talloc_free(new_number);
- return NULL;
- }
-
- /*
- * Need to create a new message now based on the old onew
- * with a new number. We can sadly not patch this in place
- * so we will need to regenerate it.
- */
-
- out = msgb_alloc_headroom(4096, 128, "changed-setup");
- if (!out) {
- LOGP(DNAT, LOGL_ERROR, "Failed to allocate.\n");
- talloc_free(new_number);
- return NULL;
- }
-
- /* copy the header */
- outptr = msgb_put(out, sizeof(*hdr48));
- memcpy(outptr, hdr48, sizeof(*hdr48));
-
- /* copy everything up to the number */
- sec_len = TLVP_VAL(&tp, GSM48_IE_CALLED_BCD) - 2 - &hdr48->data[0];
- outptr = msgb_put(out, sec_len);
- memcpy(outptr, &hdr48->data[0], sec_len);
-
- /* create the new number */
- if (strncmp(new_number, "00", 2) == 0) {
- called.type = 1;
- strncpy(called.number, new_number + 2, sizeof(called.number));
- } else {
- strncpy(called.number, new_number, sizeof(called.number));
- }
- gsm48_encode_called(out, &called);
-
- /* copy thre rest */
- msgptr = TLVP_VAL(&tp, GSM48_IE_CALLED_BCD) +
- TLVP_LEN(&tp, GSM48_IE_CALLED_BCD);
- sec_len = payload_len - (msgptr - &hdr48->data[0]);
- outptr = msgb_put(out, sec_len);
- memcpy(outptr, msgptr, sec_len);
-
- talloc_free(new_number);
- return out;
-}
-
-/**
- * Find a new SMSC address, returns an allocated string that needs to be
- * freed or is NULL.
- */
-static char *find_new_smsc(struct bsc_nat *nat, void *ctx, const char *imsi,
- const char *smsc_addr, const char *dest_nr)
-{
- struct bsc_nat_num_rewr_entry *entry;
- char *new_number = NULL;
- uint8_t dest_match = llist_empty(&nat->tpdest_match);
-
- /* We will find a new number now */
- llist_for_each_entry(entry, &nat->smsc_rewr, list) {
- regmatch_t matches[2];
-
- /* check the IMSI match */
- if (regexec(&entry->msisdn_reg, imsi, 0, NULL, 0) != 0)
- continue;
-
- /* this regexp matches... */
- if (regexec(&entry->num_reg, smsc_addr, 2, matches, 0) == 0 &&
- matches[1].rm_eo != -1)
- new_number = talloc_asprintf(ctx, "%s%s",
- entry->replace,
- &smsc_addr[matches[1].rm_so]);
- if (new_number)
- break;
- }
-
- if (!new_number)
- return NULL;
-
- /*
- * now match the number against another list
- */
- llist_for_each_entry(entry, &nat->tpdest_match, list) {
- /* check the IMSI match */
- if (regexec(&entry->msisdn_reg, imsi, 0, NULL, 0) != 0)
- continue;
-
- if (regexec(&entry->num_reg, dest_nr, 0, NULL, 0) == 0) {
- dest_match = 1;
- break;
- }
- }
-
- if (!dest_match) {
- talloc_free(new_number);
- return NULL;
- }
-
- return new_number;
-}
-
-/**
- * Clear the TP-SRR from the TPDU header
- */
-static uint8_t sms_new_tpdu_hdr(struct bsc_nat *nat, const char *imsi,
- const char *dest_nr, uint8_t hdr)
-{
- struct bsc_nat_num_rewr_entry *entry;
-
- /* We will find a new number now */
- llist_for_each_entry(entry, &nat->sms_clear_tp_srr, list) {
- /* check the IMSI match */
- if (regexec(&entry->msisdn_reg, imsi, 0, NULL, 0) != 0)
- continue;
- if (regexec(&entry->num_reg, dest_nr, 0, NULL, 0) != 0)
- continue;
-
- /* matched phone number and imsi */
- return hdr & ~0x20;
- }
-
- return hdr;
-}
-
-/**
- * Check if we need to rewrite the number. For this SMS.
- */
-static char *sms_new_dest_nr(struct bsc_nat *nat, void *ctx,
- const char *imsi, const char *dest_nr)
-{
- return match_and_rewrite_number(ctx, dest_nr, imsi,
- &nat->sms_num_rewr);
-}
-
-/**
- * This is a helper for GSM 04.11 8.2.5.2 Destination address element
- */
-void sms_encode_addr_element(struct msgb *out, const char *new_number,
- int format, int tp_data)
-{
- uint8_t new_addr_len;
- uint8_t new_addr[26];
-
- /*
- * Copy the new number. We let libosmocore encode it, then set
- * the extension followed after the length. Depending on if
- * we want to write RP we will let the TLV code add the
- * length for us or we need to use strlen... This is not very clear
- * as of 03.40 and 04.11.
- */
- new_addr_len = gsm48_encode_bcd_number(new_addr, ARRAY_SIZE(new_addr),
- 1, new_number);
- new_addr[1] = format;
- if (tp_data) {
- uint8_t *data = msgb_put(out, new_addr_len);
- memcpy(data, new_addr, new_addr_len);
- data[0] = strlen(new_number);
- } else {
- msgb_lv_put(out, new_addr_len - 1, new_addr + 1);
- }
-}
-
-static struct msgb *sms_create_new(uint8_t type, uint8_t ref,
- struct gsm48_hdr *old_hdr48,
- const uint8_t *orig_addr_ptr,
- int orig_addr_len, const char *new_number,
- const uint8_t *data_ptr, int data_len,
- uint8_t tpdu_first_byte,
- const int old_dest_len, const char *new_dest_nr)
-{
- struct gsm48_hdr *new_hdr48;
- struct msgb *out;
-
- /*
- * We need to re-create the patched structure. This is why we have
- * saved the above pointers.
- */
- out = msgb_alloc_headroom(4096, 128, "changed-smsc");
- if (!out) {
- LOGP(DNAT, LOGL_ERROR, "Failed to allocate.\n");
- return NULL;
- }
-
- out->l2h = out->data;
- msgb_v_put(out, GSM411_MT_RP_DATA_MO);
- msgb_v_put(out, ref);
- msgb_lv_put(out, orig_addr_len, orig_addr_ptr);
-
- sms_encode_addr_element(out, new_number, 0x91, 0);
-
-
- /* Patch the TPDU from here on */
-
- /**
- * Do we need to put a new TP-Destination-Address (TP-DA) here or
- * can we copy the old thing? For the TP-DA we need to find out the
- * new size.
- */
- if (new_dest_nr) {
- uint8_t *data, *new_size;
-
- /* reserve the size and write the header */
- new_size = msgb_put(out, 1);
- out->l3h = new_size + 1;
- msgb_v_put(out, tpdu_first_byte);
- msgb_v_put(out, data_ptr[1]);
-
- /* encode the new number and put it */
- if (strncmp(new_dest_nr, "00", 2) == 0)
- sms_encode_addr_element(out, new_dest_nr + 2, 0x91, 1);
- else
- sms_encode_addr_element(out, new_dest_nr, 0x81, 1);
-
- /* Copy the rest after the TP-DS */
- data = msgb_put(out, data_len - 2 - 1 - old_dest_len);
- memcpy(data, &data_ptr[2 + 1 + old_dest_len], data_len - 2 - 1 - old_dest_len);
-
- /* fill in the new size */
- new_size[0] = msgb_l3len(out);
- } else {
- msgb_v_put(out, data_len);
- msgb_tv_fixed_put(out, tpdu_first_byte, data_len - 1, &data_ptr[1]);
- }
-
- /* prepend GSM 04.08 header */
- new_hdr48 = (struct gsm48_hdr *) msgb_push(out, sizeof(*new_hdr48) + 1);
- memcpy(new_hdr48, old_hdr48, sizeof(*old_hdr48));
- new_hdr48->data[0] = msgb_l2len(out);
-
- return out;
-}
-
-/**
- * Parse the SMS and check if it needs to be rewritten
- */
-static struct msgb *rewrite_sms(struct bsc_nat *nat, struct msgb *msg,
- struct bsc_nat_parsed *parsed, const char *imsi,
- struct gsm48_hdr *hdr48, const uint32_t len)
-{
- unsigned int payload_len;
- unsigned int cp_len;
-
- uint8_t ref;
- uint8_t orig_addr_len, *orig_addr_ptr;
- uint8_t dest_addr_len, *dest_addr_ptr;
- uint8_t data_len, *data_ptr;
- char smsc_addr[30];
-
-
- uint8_t dest_len, orig_dest_len;
- char _dest_nr[30];
- char *dest_nr;
- char *new_dest_nr;
-
- char *new_number = NULL;
- uint8_t tpdu_hdr;
- struct msgb *out;
-
- payload_len = len - sizeof(*hdr48);
- if (payload_len < 1) {
- LOGP(DNAT, LOGL_ERROR, "SMS too short for things. %d\n", payload_len);
- return NULL;
- }
-
- cp_len = hdr48->data[0];
- if (payload_len + 1 < cp_len) {
- LOGP(DNAT, LOGL_ERROR, "SMS RPDU can not fit in: %d %d\n", cp_len, payload_len);
- return NULL;
- }
-
- if (hdr48->data[1] != GSM411_MT_RP_DATA_MO)
- return NULL;
-
- if (cp_len < 5) {
- LOGP(DNAT, LOGL_ERROR, "RD-DATA can not fit in the CP len: %d\n", cp_len);
- return NULL;
- }
-
- /* RP */
- ref = hdr48->data[2];
- orig_addr_len = hdr48->data[3];
- orig_addr_ptr = &hdr48->data[4];
-
- /* the +1 is for checking if the following element has some space */
- if (cp_len < 3 + orig_addr_len + 1) {
- LOGP(DNAT, LOGL_ERROR, "RP-Originator addr does not fit: %d\n", orig_addr_len);
- return NULL;
- }
-
- dest_addr_len = hdr48->data[3 + orig_addr_len + 1];
- dest_addr_ptr = &hdr48->data[3 + orig_addr_len + 2];
-
- if (cp_len < 3 + orig_addr_len + 1 + dest_addr_len + 1) {
- LOGP(DNAT, LOGL_ERROR, "RP-Destination addr does not fit: %d\n", dest_addr_len);
- return NULL;
- }
- gsm48_decode_bcd_number(smsc_addr, ARRAY_SIZE(smsc_addr), dest_addr_ptr - 1, 1);
-
- data_len = hdr48->data[3 + orig_addr_len + 1 + dest_addr_len + 1];
- data_ptr = &hdr48->data[3 + orig_addr_len + 1 + dest_addr_len + 2];
-
- if (cp_len < 3 + orig_addr_len + 1 + dest_addr_len + 1 + data_len) {
- LOGP(DNAT, LOGL_ERROR, "RP-Data does not fit: %d\n", data_len);
- return NULL;
- }
-
- if (data_len < 3) {
- LOGP(DNAT, LOGL_ERROR, "SMS-SUBMIT is too short.\n");
- return NULL;
- }
-
- /* TP-PDU starts here */
- if ((data_ptr[0] & 0x03) != GSM340_SMS_SUBMIT_MS2SC)
- return NULL;
-
- /*
- * look into the phone number. The length is in semi-octets, we will
- * need to add the byte for the number type as well.
- */
- orig_dest_len = data_ptr[2];
- dest_len = ((orig_dest_len + 1) / 2) + 1;
- if (data_len < dest_len + 3 || dest_len < 2) {
- LOGP(DNAT, LOGL_ERROR, "SMS-SUBMIT can not have TP-DestAddr.\n");
- return NULL;
- }
-
- if ((data_ptr[3] & 0x80) == 0) {
- LOGP(DNAT, LOGL_ERROR, "TP-DestAddr has extension. Not handled.\n");
- return NULL;
- }
-
- if ((data_ptr[3] & 0x0F) == 0) {
- LOGP(DNAT, LOGL_ERROR, "TP-DestAddr is of unknown type.\n");
- return NULL;
- }
-
- /**
- * Besides of what I think I read in GSM 03.40 and 04.11 the TP-DA
- * contains the semi-octets as length (strlen), change it to the
- * the number of bytes, but then change it back.
- */
- data_ptr[2] = dest_len;
- gsm48_decode_bcd_number(_dest_nr + 2, ARRAY_SIZE(_dest_nr) - 2,
- &data_ptr[2], 1);
- data_ptr[2] = orig_dest_len;
- if ((data_ptr[3] & 0x70) == 0x10) {
- _dest_nr[0] = _dest_nr[1] = '0';
- dest_nr = &_dest_nr[0];
- } else {
- dest_nr = &_dest_nr[2];
- }
-
- /**
- * Call functions to rewrite the data
- */
- tpdu_hdr = sms_new_tpdu_hdr(nat, imsi, dest_nr, data_ptr[0]);
- new_number = find_new_smsc(nat, msg, imsi, smsc_addr, dest_nr);
- new_dest_nr = sms_new_dest_nr(nat, msg, imsi, dest_nr);
-
- if (tpdu_hdr == data_ptr[0] && !new_number && !new_dest_nr)
- return NULL;
-
- out = sms_create_new(GSM411_MT_RP_DATA_MO, ref, hdr48,
- orig_addr_ptr, orig_addr_len,
- new_number ? new_number : smsc_addr,
- data_ptr, data_len, tpdu_hdr,
- dest_len, new_dest_nr);
- talloc_free(new_number);
- talloc_free(new_dest_nr);
- return out;
-}
-
-struct msgb *bsc_nat_rewrite_msg(struct bsc_nat *nat, struct msgb *msg, struct bsc_nat_parsed *parsed, const char *imsi)
-{
- struct gsm48_hdr *hdr48;
- uint32_t len;
- uint8_t msg_type, proto;
- struct msgb *new_msg = NULL, *sccp;
- uint8_t link_id;
-
- if (!imsi || strlen(imsi) < 5)
- return msg;
-
- /* only care about DTAP messages */
- if (parsed->bssap != BSSAP_MSG_DTAP)
- return msg;
- if (!parsed->dest_local_ref)
- return msg;
-
- hdr48 = bsc_unpack_dtap(parsed, msg, &len);
- if (!hdr48)
- return msg;
-
- link_id = msg->l3h[1];
- proto = hdr48->proto_discr & 0x0f;
- msg_type = hdr48->msg_type & 0xbf;
-
- if (proto == GSM48_PDISC_CC && msg_type == GSM48_MT_CC_SETUP)
- new_msg = rewrite_setup(nat, msg, parsed, imsi, hdr48, len);
- else if (proto == GSM48_PDISC_SMS && msg_type == GSM411_MT_CP_DATA)
- new_msg = rewrite_sms(nat, msg, parsed, imsi, hdr48, len);
-
- if (!new_msg)
- return msg;
-
- /* wrap with DTAP, SCCP, then IPA. TODO: Stop copying */
- gsm0808_prepend_dtap_header(new_msg, link_id);
- sccp = sccp_create_dt1(parsed->dest_local_ref, new_msg->data, new_msg->len);
- talloc_free(new_msg);
-
- if (!sccp) {
- LOGP(DNAT, LOGL_ERROR, "Failed to allocate.\n");
- return msg;
- }
-
- ipaccess_prepend_header(sccp, IPAC_PROTO_SCCP);
-
- /* the parsed hangs off from msg but it needs to survive */
- talloc_steal(sccp, parsed);
- msgb_free(msg);
- return sccp;
-}
-
-static void num_rewr_free_data(struct bsc_nat_num_rewr_entry *entry)
-{
- regfree(&entry->msisdn_reg);
- regfree(&entry->num_reg);
- talloc_free(entry->replace);
-}
-
-void bsc_nat_num_rewr_entry_adapt(void *ctx, struct llist_head *head,
- const struct osmo_config_list *list)
-{
- struct bsc_nat_num_rewr_entry *entry, *tmp;
- struct osmo_config_entry *cfg_entry;
-
- /* free the old data */
- llist_for_each_entry_safe(entry, tmp, head, list) {
- num_rewr_free_data(entry);
- llist_del(&entry->list);
- talloc_free(entry);
- }
-
-
- if (!list)
- return;
-
- llist_for_each_entry(cfg_entry, &list->entry, list) {
- char *regexp;
- if (cfg_entry->text[0] == '+') {
- LOGP(DNAT, LOGL_ERROR,
- "Plus is not allowed in the number\n");
- continue;
- }
-
- entry = talloc_zero(ctx, struct bsc_nat_num_rewr_entry);
- if (!entry) {
- LOGP(DNAT, LOGL_ERROR,
- "Allication of the num_rewr entry failed.\n");
- continue;
- }
-
- entry->replace = talloc_strdup(entry, cfg_entry->text);
- if (!entry->replace) {
- LOGP(DNAT, LOGL_ERROR,
- "Failed to copy the replacement text.\n");
- talloc_free(entry);
- continue;
- }
-
- /* we will now build a regexp string */
- if (cfg_entry->mcc[0] == '^') {
- regexp = talloc_strdup(entry, cfg_entry->mcc);
- } else {
- regexp = talloc_asprintf(entry, "^%s%s",
- cfg_entry->mcc[0] == '*' ?
- "[0-9][0-9][0-9]" : cfg_entry->mcc,
- cfg_entry->mnc[0] == '*' ?
- "[0-9][0-9]" : cfg_entry->mnc);
- }
-
- if (!regexp) {
- LOGP(DNAT, LOGL_ERROR, "Failed to create a regexp string.\n");
- talloc_free(entry);
- continue;
- }
-
- if (regcomp(&entry->msisdn_reg, regexp, 0) != 0) {
- LOGP(DNAT, LOGL_ERROR,
- "Failed to compile regexp '%s'\n", regexp);
- talloc_free(regexp);
- talloc_free(entry);
- continue;
- }
-
- talloc_free(regexp);
- if (regcomp(&entry->num_reg, cfg_entry->option, REG_EXTENDED) != 0) {
- LOGP(DNAT, LOGL_ERROR,
- "Failed to compile regexp '%s'\n", cfg_entry->option);
- regfree(&entry->msisdn_reg);
- talloc_free(entry);
- continue;
- }
-
- /* we have copied the number */
- llist_add_tail(&entry->list, head);
- }
-}