/*! \file gsm23003.c * Utility function implementations related to 3GPP TS 23.003 */ /* * (C) 2017 sysmocom - s.f.m.c. GmbH * Author: Neels Hofmeyr * All Rights Reserved * * SPDX-License-Identifier: GPL-2.0+ * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. * */ #include #include #include #include #include #include #include #include static bool is_n_digits(const char *str, int min_digits, int max_digits) { int len; /* Use unsigned char * to avoid a compiler warning of * "error: array subscript has type 'char' [-Werror=char-subscripts]" */ const unsigned char *pos = (const unsigned char *)str; if (!pos) return min_digits < 1; for (len = 0; *pos && len < max_digits; len++, pos++) if (!isdigit(*pos)) return false; if (len < min_digits) return false; /* With not too many digits, we should have reached *str == nul */ if (*pos) return false; return true; } /*! Determine whether the given IMSI is valid according to 3GPP TS 23.003. * \param imsi IMSI digits in ASCII string representation. * \returns true when the IMSI is valid, false for invalid characters or number * of digits. */ bool osmo_imsi_str_valid(const char *imsi) { return is_n_digits(imsi, GSM23003_IMSI_MIN_DIGITS, GSM23003_IMSI_MAX_DIGITS); } /*! Determine whether the given MSISDN is valid according to 3GPP TS 23.003. * \param msisdn MSISDN digits in ASCII string representation. * \returns true when the MSISDN is valid, false for invalid characters or number * of digits. */ bool osmo_msisdn_str_valid(const char *msisdn) { return is_n_digits(msisdn, 1, 15); } /*! Determine whether the given IMEI is valid according to 3GPP TS 23.003, * Section 6.2.1. It consists of 14 digits, the 15th check digit is not * intended for digital transmission. * \param imei IMEI digits in ASCII string representation. * \param with_15th_digit when true, expect the 15th digit to be present and * verify it. * \returns true when the IMEI is valid, false for invalid characters or number * of digits. */ bool osmo_imei_str_valid(const char *imei, bool with_15th_digit) { if (with_15th_digit) return is_n_digits(imei, 15, 15) && osmo_luhn(imei, 14) == imei[14]; else return is_n_digits(imei, 14, 14); } /*! Return MCC string as standardized 3-digit with leading zeros. * \param[in] mcc MCC value. * \returns string in static buffer. */ const char *osmo_mcc_name(uint16_t mcc) { static char buf[8]; snprintf(buf, sizeof(buf), "%03u", mcc); return buf; } /*! Return MNC string as standardized 2- or 3-digit with leading zeros. * \param[in] mnc MNC value. * \param[in] mnc_3_digits True if an MNC should fill three digits, only has an effect if MNC < 100. * \returns string in static buffer. */ const char *osmo_mnc_name(uint16_t mnc, bool mnc_3_digits) { static char buf[8]; snprintf(buf, sizeof(buf), "%0*u", mnc_3_digits ? 3 : 2, mnc); return buf; } static inline void plmn_name(char *buf, size_t buflen, const struct osmo_plmn_id *plmn) { snprintf(buf, buflen, "%s-%s", osmo_mcc_name(plmn->mcc), osmo_mnc_name(plmn->mnc, plmn->mnc_3_digits)); } /*! Return MCC-MNC string as standardized 3-digit-dash-2/3-digit with leading zeros. * \param[in] plmn MCC-MNC value. * \returns string in static buffer. */ const char *osmo_plmn_name(const struct osmo_plmn_id *plmn) { static char buf[16]; plmn_name(buf, sizeof(buf), plmn); return buf; } /*! Same as osmo_mcc_mnc_name(), but returning in a different static buffer. * \param[in] plmn MCC-MNC value. * \returns string in static buffer. */ const char *osmo_plmn_name2(const struct osmo_plmn_id *plmn) { static char buf[16]; plmn_name(buf, sizeof(buf), plmn); return buf; } /*! Return MCC-MNC-LAC as string, in a static buffer. * \param[in] lai LAI to encode, the rac member is ignored. * \returns Static string buffer. */ const char *osmo_lai_name(const struct osmo_location_area_id *lai) { static char buf[32]; snprintf(buf, sizeof(buf), "%s-%u", osmo_plmn_name(&lai->plmn), lai->lac); return buf; } static const char *_cgi_name(const struct osmo_cell_global_id *cgi, char *buf, size_t buflen) { snprintf(buf, buflen, "%s-%u", osmo_lai_name(&cgi->lai), cgi->cell_identity); return buf; } /*! Return MCC-MNC-LAC-CI as string, in a static buffer. * \param[in] cgi CGI to encode. * \returns Static string buffer. */ const char *osmo_cgi_name(const struct osmo_cell_global_id *cgi) { static char buf[32]; return _cgi_name(cgi, buf, sizeof(buf)); } /*! Same as osmo_cgi_name(), but uses a different static buffer. * Useful for printing two distinct CGIs in the same printf format. * \param[in] cgi CGI to encode. * \returns Static string buffer. */ const char *osmo_cgi_name2(const struct osmo_cell_global_id *cgi) { static char buf[32]; return _cgi_name(cgi, buf, sizeof(buf)); } static void to_bcd(uint8_t *bcd, uint16_t val) { bcd[2] = val % 10; val = val / 10; bcd[1] = val % 10; val = val / 10; bcd[0] = val % 10; } const char *osmo_gummei_name(const struct osmo_gummei *gummei) { static char buf[32]; snprintf(buf, sizeof(buf), "%s-%04x-%02x", osmo_plmn_name(&gummei->plmn), gummei->mme.group_id, gummei->mme.code); return buf; } /* Convert MCC + MNC to BCD representation * \param[out] bcd_dst caller-allocated memory for output * \param[in] mcc Mobile Country Code * \param[in] mnc Mobile Network Code * \param[in] mnc_3_digits true if the MNC shall have three digits. * * Convert given mcc and mnc to BCD and write to *bcd_dst, which must be an * allocated buffer of (at least) 3 bytes length. Encode the MNC in three * digits if its integer value is > 99, or if mnc_3_digits is passed true. * Encode an MNC < 100 with mnc_3_digits passed as true as a three-digit MNC * with leading zeros in the BCD representation. */ void osmo_plmn_to_bcd(uint8_t *bcd_dst, const struct osmo_plmn_id *plmn) { uint8_t bcd[3]; to_bcd(bcd, plmn->mcc); bcd_dst[0] = bcd[0] | (bcd[1] << 4); bcd_dst[1] = bcd[2]; to_bcd(bcd, plmn->mnc); if (plmn->mnc > 99 || plmn->mnc_3_digits) { bcd_dst[1] |= bcd[2] << 4; bcd_dst[2] = bcd[0] | (bcd[1] << 4); } else { bcd_dst[1] |= 0xf << 4; bcd_dst[2] = bcd[1] | (bcd[2] << 4); } } /* Convert given 3-byte BCD buffer to integers and write results to *mcc and * *mnc. The first three BCD digits result in the MCC and the remaining ones in * the MNC. Return mnc_3_digits as false if the MNC's most significant digit is encoded as 0xF, true * otherwise; i.e. true if MNC > 99 or if it is represented with leading zeros instead of 0xF. * \param[in] bcd_src 3-byte BCD buffer containing MCC+MNC representations. * \param[out] mcc MCC result buffer, or NULL. * \param[out] mnc MNC result buffer, or NULL. * \param[out] mnc_3_digits Result buffer for 3-digit flag, or NULL. */ void osmo_plmn_from_bcd(const uint8_t *bcd_src, struct osmo_plmn_id *plmn) { plmn->mcc = (bcd_src[0] & 0x0f) * 100 + (bcd_src[0] >> 4) * 10 + (bcd_src[1] & 0x0f); if ((bcd_src[1] & 0xf0) == 0xf0) { plmn->mnc = (bcd_src[2] & 0x0f) * 10 + (bcd_src[2] >> 4); plmn->mnc_3_digits = false; } else { plmn->mnc = (bcd_src[2] & 0x0f) * 100 + (bcd_src[2] >> 4) * 10 + (bcd_src[1] >> 4); plmn->mnc_3_digits = true; } } /* Convert string to MNC, detecting 3-digit MNC with leading zeros. * Return mnc_3_digits as false if the MNC's most significant digit is encoded as 0xF, true * otherwise; i.e. true if MNC > 99 or if it is represented with leading zeros instead of 0xF. * \param mnc_str[in] String representation of an MNC, with or without leading zeros. * \param mnc[out] MNC result buffer, or NULL. * \param[out] mnc_3_digits Result buffer for 3-digit flag, or NULL. * \returns zero on success, -EINVAL in case of surplus characters, negative errno in case of conversion * errors. In case of error, do not modify the out-arguments. */ int osmo_mnc_from_str(const char *mnc_str, uint16_t *mnc, bool *mnc_3_digits) { long int _mnc = 0; bool _mnc_3_digits = false; char *endptr; int rc = 0; if (!mnc_str || !isdigit(mnc_str[0]) || strlen(mnc_str) > 3) return -EINVAL; errno = 0; _mnc = strtol(mnc_str, &endptr, 10); if (errno) rc = -errno; else if (*endptr) return -EINVAL; if (_mnc < 0 || _mnc > 999) return -ERANGE; _mnc_3_digits = strlen(mnc_str) > 2; if (mnc) *mnc = (uint16_t)_mnc; if (mnc_3_digits) *mnc_3_digits = _mnc_3_digits; return rc; } /* Compare two MNC with three-digit flag. * The mnc_3_digits flags passed in only have an effect if the MNC are < 100, i.e. if they would amount * to a change in leading zeros in a BCD representation. An MNC >= 100 implies three digits, and the flag * is actually ignored. * \param a_mnc[in] "Left" side MNC. * \param a_mnc_3_digits[in] "Left" side three-digits flag. * \param b_mnc[in] "Right" side MNC. * \param b_mnc_3_digits[in] "Right" side three-digits flag. * \returns 0 if the MNC are equal, -1 if a < b or a shorter, 1 if a > b or a longer. */ int osmo_mnc_cmp(uint16_t a_mnc, bool a_mnc_3_digits, uint16_t b_mnc, bool b_mnc_3_digits) { if (a_mnc < b_mnc) return -1; if (a_mnc > b_mnc) return 1; /* a_mnc == b_mnc, but same amount of leading zeros? */ if (a_mnc < 100 && a_mnc_3_digits != b_mnc_3_digits) return a_mnc_3_digits ? 1 : -1; return 0; } /* Compare two PLMN. * \param a[in] "Left" side PLMN. * \param b[in] "Right" side PLMN. * \returns 0 if the PLMN are equal, -1 if a < b or a shorter, 1 if a > b or a longer. */ int osmo_plmn_cmp(const struct osmo_plmn_id *a, const struct osmo_plmn_id *b) { if (a == b) return 0; if (a->mcc < b->mcc) return -1; if (a->mcc > b->mcc) return 1; return osmo_mnc_cmp(a->mnc, a->mnc_3_digits, b->mnc, b->mnc_3_digits); } /*! Generate TS 23.003 Section 19.2 Home Network Realm/Domain (text form) * \param out[out] caller-provided output buffer, at least 33 bytes long * \param plmn[in] Osmocom representation of PLMN ID (MCC + MNC) * \returns number of characters printed (excluding NUL); negative on error */ int osmo_gen_home_network_domain(char *out, const struct osmo_plmn_id *plmn) { if (plmn->mcc > 999) return -EINVAL; if (plmn->mnc > 999) return -EINVAL; return sprintf(out, "epc.mnc%03u.mcc%03u.3gppnetwork.org", plmn->mnc, plmn->mcc); } /*! Parse a TS 23.003 Section 19.2 Home Network Realm/Domain (text form) into a \ref osmo_plmn_id * \param out[out] caller-allocated output structure * \param in[in] character string representation to be parsed * \returns 0 on success; negative on error */ int osmo_parse_home_network_domain(struct osmo_plmn_id *out, const char *in) { int rc; memset(out, 0, sizeof(*out)); rc = sscanf(in, "epc.mnc%03hu.mcc%03hu.3gppnetwork.org", &out->mnc, &out->mcc); if (rc < 0) return rc; if (rc != 2) return -EINVAL; return 0; } /*! Generate TS 23.003 Section 19.4.2.4 MME Domain (text form) * \param out[out] caller-provided output buffer, at least 56 bytes long * \param gummei[in] Structure representing the Globally Unique MME Identifier * \returns number of characters printed (excluding NUL); negative on error */ int osmo_gen_mme_domain(char *out, const struct osmo_gummei *gummei) { char domain[GSM23003_HOME_NETWORK_DOMAIN_LEN+1]; int rc; rc = osmo_gen_home_network_domain(domain, &gummei->plmn); if (rc < 0) return rc; return sprintf(out, "mmec%02x.mmegi%04x.mme.%s", gummei->mme.code, gummei->mme.group_id, domain); } /*! Parse a TS 23.003 Section 19.4.2.4 MME Domain (text form) into a \ref osmo_gummei * \param out[out] caller-allocated output GUMMEI structure * \param in[in] character string representation to be parsed * \returns 0 on success; negative on error */ int osmo_parse_mme_domain(struct osmo_gummei *out, const char *in) { int rc; memset(out, 0, sizeof(*out)); rc = sscanf(in, "mmec%02hhx.mmegi%04hx.mme.epc.mnc%03hu.mcc%03hu.3gppnetwork.org", &out->mme.code, &out->mme.group_id, &out->plmn.mnc, &out->plmn.mcc); if (rc < 0) return rc; if (rc != 4) return -EINVAL; return 0; } /*! Generate TS 23.003 Section 19.4.2.4 MME Group Domain (text form) * \param out[out] caller-provided output buffer, at least 56 bytes long * \param mmegi[in] MME Group Identifier * \param plmn[in] Osmocom representation of PLMN ID (MCC + MNC) * \returns number of characters printed (excluding NUL); negative on error */ int osmo_gen_mme_group_domain(char *out, uint16_t mmegi, const struct osmo_plmn_id *plmn) { char domain[GSM23003_HOME_NETWORK_DOMAIN_LEN+1]; int rc; rc = osmo_gen_home_network_domain(domain, plmn); if (rc < 0) return rc; return sprintf(out, "mmegi%04x.mme.%s", mmegi, domain); }