#pragma once #include #include #include #define GSM0464_CIPH_MAX_BLOCK 1523 /* 3GPP TS 24.008 ยง 10.5.5.3 */ enum gprs_ciph_algo { GPRS_ALGO_GEA0 = 0, GPRS_ALGO_GEA1 = 1, GPRS_ALGO_GEA2 = 2, GPRS_ALGO_GEA3 = 3, GPRS_ALGO_GEA4 = 4, _GPRS_ALGO_NUM }; /* 3GPP TS 04.64 Table A.1: */ enum gprs_cipher_direction { GPRS_CIPH_MS2SGSN = 0, GPRS_CIPH_SGSN2MS = 1, }; extern const struct value_string gprs_cipher_names[]; /* An implementation of a GPRS cipher */ struct gprs_cipher_impl { struct llist_head list; enum gprs_ciph_algo algo; const char *name; unsigned int priority; /* As specified in 04.64 Annex A. Uses Kc, IV and direction * to generate the 1523 bytes cipher stream that need to be * XORed wit the plaintext for encrypt / ciphertext for decrypt */ int (*run)(uint8_t *out, uint16_t len, uint8_t *kc, uint32_t iv, enum gprs_cipher_direction direction); }; /* register a cipher with the core (from a plugin) */ int gprs_cipher_register(struct gprs_cipher_impl *ciph); /* load all available GPRS cipher plugins */ int gprs_cipher_load(const char *path); /* function to be called by core code */ int gprs_cipher_run(uint8_t *out, uint16_t len, enum gprs_ciph_algo algo, uint8_t *kc, uint32_t iv, enum gprs_cipher_direction dir); /* Do we have an implementation for this cipher? */ int gprs_cipher_supported(enum gprs_ciph_algo algo); /* Return key length for supported cipher, in bytes */ unsigned gprs_cipher_key_length(enum gprs_ciph_algo algo); /* GSM TS 04.64 / Section A.2.1 : Generation of 'input' */ uint32_t gprs_cipher_gen_input_ui(uint32_t iov_ui, uint8_t sapi, uint32_t lfn, uint32_t oc); /* GSM TS 04.64 / Section A.2.1 : Generation of 'input' */ uint32_t gprs_cipher_gen_input_i(uint32_t iov_i, uint32_t lfn, uint32_t oc);