/*! \file gsm0411_utils.c * Point-to-Point (PP) Short Message Service (SMS). * Support on Mobile Radio Interface * 3GPP TS 04.11 version 7.1.0 Release 1998 / ETSI TS 100 942 V7.1.0. */ /* * (C) 2008 by Daniel Willmann * (C) 2009 by Harald Welte * (C) 2010-2013 by Holger Hans Peter Freyther * (C) 2010 by On-Waves * (C) 2011 by Andreas Eversberg * * All Rights Reserved * * 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, see . * */ #include "../../config.h" #include #include #include #include #include #include #include #include #include /*! \addtogroup sms * @{ */ #define GSM411_ALLOC_SIZE 1024 #define GSM411_ALLOC_HEADROOM 128 /*! Allocate a message buffer for use as TS 04.11 message * \returns allocated message buffer */ struct msgb *gsm411_msgb_alloc(void) { return msgb_alloc_headroom(GSM411_ALLOC_SIZE, GSM411_ALLOC_HEADROOM, "GSM 04.11"); } /*! Turn int into semi-octet representation: 98 => 0x89 * \param[in] integer value representing decimal number 0..99 * \returns BSC encoded as nibbles, swapped */ uint8_t gsm411_bcdify(uint8_t value) { uint8_t ret; ret = value / 10; ret |= (value % 10) << 4; return ret; } /*! Turn semi-octet representation into int: 0x89 => 98 * \param[in] value byte containing two BCD nibbles in revere order * \returns integer representing decoded, re-ordered nibbles */ uint8_t gsm411_unbcdify(uint8_t value) { uint8_t ret; if ((value & 0x0F) > 9 || (value >> 4) > 9) LOGP(DLSMS, LOGL_ERROR, "gsm411_unbcdify got too big nibble: 0x%02X\n", value); ret = (value&0x0F)*10; ret += value>>4; return ret; } /*! Generate 03.40 TP-SCTS * \param[out] scts Caller-provided buffer to store SCTS (7 octets) * \param[in] time to encode */ void gsm340_gen_scts(uint8_t *scts, time_t time) { struct tm *tm = gmtime(&time); *scts++ = gsm411_bcdify(tm->tm_year % 100); *scts++ = gsm411_bcdify(tm->tm_mon + 1); *scts++ = gsm411_bcdify(tm->tm_mday); *scts++ = gsm411_bcdify(tm->tm_hour); *scts++ = gsm411_bcdify(tm->tm_min); *scts++ = gsm411_bcdify(tm->tm_sec); #ifdef HAVE_TM_GMTOFF_IN_TM *scts++ = gsm411_bcdify(tm->tm_gmtoff/(60*15)); #else #pragma message ("find a portable way to obtain timezone offset") *scts++ = 0; #endif } /*! Decode 03.40 TP-SCTS (into utc/gmt timestamp) * \param[in] scts SMS Center Time Stamp * \return time in UTC time_t format */ time_t gsm340_scts(uint8_t *scts) { struct tm tm; uint8_t yr = gsm411_unbcdify(*scts++); int ofs; memset(&tm, 0x00, sizeof(struct tm)); if (yr <= 80) tm.tm_year = 100 + yr; else tm.tm_year = yr; tm.tm_mon = gsm411_unbcdify(*scts++) - 1; tm.tm_mday = gsm411_unbcdify(*scts++); tm.tm_hour = gsm411_unbcdify(*scts++); tm.tm_min = gsm411_unbcdify(*scts++); tm.tm_sec = gsm411_unbcdify(*scts++); #ifdef HAVE_TM_GMTOFF_IN_TM tm.tm_gmtoff = gsm411_unbcdify(*scts++) * 15*60; #endif /* according to gsm 03.40 time zone is "expressed in quarters of an hour" */ ofs = gsm411_unbcdify(*scts++) * 15*60; return mktime(&tm) - ofs; } /* Return the default validity period in minutes */ static unsigned long gsm340_vp_default(void) { unsigned long minutes; /* Default validity: two days */ minutes = 24 * 60 * 2; return minutes; } /* Decode validity period format 'relative' */ static unsigned long gsm340_vp_relative(uint8_t *sms_vp) { /* Chapter 9.2.3.12.1 */ uint8_t vp; unsigned long minutes; vp = *(sms_vp); if (vp <= 143) minutes = (vp + 1) * 5; else if (vp <= 167) minutes = 12*60 + (vp-143) * 30; else if (vp <= 196) minutes = (vp-166) * 60 * 24; else minutes = (vp-192) * 60 * 24 * 7; return minutes; } /* Decode validity period format 'absolute' */ static unsigned long gsm340_vp_absolute(uint8_t *sms_vp) { /* Chapter 9.2.3.12.2 */ time_t expires, now; unsigned long minutes; expires = gsm340_scts(sms_vp); now = time(NULL); if (expires <= now) minutes = 0; else minutes = (expires-now)/60; return minutes; } /* Decode validity period format 'relative in integer representation' */ static unsigned long gsm340_vp_relative_integer(uint8_t *sms_vp) { uint8_t vp; unsigned long minutes; vp = *(sms_vp); if (vp == 0) { LOGP(DLSMS, LOGL_ERROR, "reserved relative_integer validity period\n"); return gsm340_vp_default(); } minutes = vp/60; return minutes; } /* Decode validity period format 'relative in semi-octet representation' */ static unsigned long gsm340_vp_relative_semioctet(uint8_t *sms_vp) { unsigned long minutes; minutes = gsm411_unbcdify(*sms_vp++)*60; /* hours */ minutes += gsm411_unbcdify(*sms_vp++); /* minutes */ minutes += gsm411_unbcdify(*sms_vp++)/60; /* seconds */ return minutes; } /*! decode validity period. return minutes * \param[in] sms_vpf Validity Period Format in 03.40 encoding * \param[in] sms_vp Validity Period Information Element * \returns validity period in minutes */ unsigned long gsm340_validity_period(uint8_t sms_vpf, uint8_t *sms_vp) { uint8_t fi; /* functionality indicator */ switch (sms_vpf) { case GSM340_TP_VPF_RELATIVE: return gsm340_vp_relative(sms_vp); case GSM340_TP_VPF_ABSOLUTE: return gsm340_vp_absolute(sms_vp); case GSM340_TP_VPF_ENHANCED: /* Chapter 9.2.3.12.3 */ fi = *sms_vp++; /* ignore additional fi */ if (fi & (1<<7)) sms_vp++; /* read validity period format */ switch (fi & 0x7) { case 0x0: return gsm340_vp_default(); /* no vpf specified */ case 0x1: return gsm340_vp_relative(sms_vp); case 0x2: return gsm340_vp_relative_integer(sms_vp); case 0x3: return gsm340_vp_relative_semioctet(sms_vp); default: /* The GSM spec says that the SC should reject any unsupported and/or undefined values. FIXME */ LOGP(DLSMS, LOGL_ERROR, "Reserved enhanced validity period format\n"); return gsm340_vp_default(); } case GSM340_TP_VPF_NONE: default: return gsm340_vp_default(); } } /*! determine coding alphabet dependent on GSM 03.38 Section 4 DCS * \param[in] dcs Data Coding Scheme in 03.38 encoding * \returns libosmogsm internal enum \ref sms_alphabet */ enum sms_alphabet gsm338_get_sms_alphabet(uint8_t dcs) { uint8_t cgbits = dcs >> 4; enum sms_alphabet alpha = DCS_NONE; if ((cgbits & 0xc) == 0) { if (cgbits & 2) { LOGP(DLSMS, LOGL_NOTICE, "Compressed SMS not supported yet\n"); return -1; } switch ((dcs >> 2)&0x03) { case 0: alpha = DCS_7BIT_DEFAULT; break; case 1: alpha = DCS_8BIT_DATA; break; case 2: alpha = DCS_UCS2; break; } } else if (cgbits == 0xc || cgbits == 0xd) alpha = DCS_7BIT_DEFAULT; else if (cgbits == 0xe) alpha = DCS_UCS2; else if (cgbits == 0xf) { if (dcs & 4) alpha = DCS_8BIT_DATA; else alpha = DCS_7BIT_DEFAULT; } return alpha; } /*! generate a TPDU address field compliant with 03.40 sec. 9.1.2.5 * \param[out] oa caller-provided output buffer * \param[in] oa_len caller-specified length of \a oa in bytes * \param[in] type GSM340_TYPE_* * \param[in] plan Numbering Plan * \param[in] number string containing number * \reurns number of bytes of \a oa that have been used */ int gsm340_gen_oa(uint8_t *oa, unsigned int oa_len, uint8_t type, uint8_t plan, const char *number) { int len_in_bytes; oa[1] = 0x80 | (type << 4) | plan; if (type == GSM340_TYPE_ALPHA_NUMERIC) { /* * TODO/FIXME: what is the 'useful semi-octets' excluding any * semi octet containing only fill bits. * The current code picks the number of bytes written by the * 7bit encoding routines and multiplies it by two. */ gsm_7bit_encode_n(&oa[2], oa_len - 2, number, &len_in_bytes); oa[0] = len_in_bytes * 2; len_in_bytes += 2; } else { /* prevent buffer overflows */ if (strlen(number) > 20) number = ""; len_in_bytes = gsm48_encode_bcd_number(oa, oa_len, 1, number); /* GSM 03.40 tells us the length is in 'useful semi-octets' */ oa[0] = strlen(number) & 0xff; } return len_in_bytes; } /*! Prefix \ref msgb with a RP header * \param msg Message Buffer containing message * \param[in] rp_msg_type RP Message Type * \param[in] rp_msg_ref RP Message Reference * \returns 0 */ int gsm411_push_rp_header(struct msgb *msg, uint8_t rp_msg_type, uint8_t rp_msg_ref) { struct gsm411_rp_hdr *rp; uint8_t len = msg->len; /* GSM 04.11 RP-DATA header */ rp = (struct gsm411_rp_hdr *)msgb_push(msg, sizeof(*rp)); rp->len = len + 2; rp->msg_type = rp_msg_type; rp->msg_ref = rp_msg_ref; /* FIXME: Choose randomly */ return 0; } /*! Prefix \ref msgb with a 04.08/04.11 CP header * \param msg Message Buffer containing message * \param[in] proto Protocol * \param[in] trans Transaction * \param[in] msg_type Message Type * \retrns 0 */ int gsm411_push_cp_header(struct msgb *msg, uint8_t proto, uint8_t trans, uint8_t msg_type) { /* Outgoing proto_discr needs the highest bit set */ gsm0480_l3hdr_push(msg, proto | (trans << 4), msg_type); return 0; } /*! @} */