| /*! \file gsm23003.c |
| * Utility function implementations related to 3GPP TS 23.003 */ |
| /* |
| * (C) 2017 sysmocom - s.f.m.c. GmbH <info@sysmocom.de> |
| * Author: Neels Hofmeyr <nhofmeyr@sysmocom.de> |
| * 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 <ctype.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <errno.h> |
| #include <string.h> |
| |
| #include <osmocom/gsm/gsm23003.h> |
| #include <osmocom/gsm/protocol/gsm_23_003.h> |
| |
| 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); |
| } |
| |
| /*! 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; |
| } |
| |
| /* 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); |
| } |