diff --git a/core/lib/ccm-star.c b/core/lib/ccm-star.c index da4b9382a..e093c8703 100644 --- a/core/lib/ccm-star.c +++ b/core/lib/ccm-star.c @@ -45,30 +45,26 @@ /* see RFC 3610 */ #define CCM_STAR_AUTH_FLAGS(Adata, M) ((Adata ? (1u << 6) : 0) | (((M - 2u) >> 1) << 3) | 1u) #define CCM_STAR_ENCRYPTION_FLAGS 1 -#define CCM_STAR_NONCE_MAX_IV_LENGTH 13 /*---------------------------------------------------------------------------*/ static void -set_nonce(uint8_t *nonce, +set_nonce(uint8_t *iv, uint8_t flags, - const uint8_t *iv, uint8_t iv_len, + const uint8_t *nonce, uint8_t counter) { /* 1 byte|| 8 bytes || 4 bytes || 1 byte || 2 bytes */ /* flags || extended_source_address || frame_counter || sec_lvl || counter */ - if(iv_len > CCM_STAR_NONCE_MAX_IV_LENGTH) - iv_len = CCM_STAR_NONCE_MAX_IV_LENGTH; - - nonce[0] = flags; - memcpy(nonce + 1, iv, iv_len); - memset(nonce + iv_len + 1, 0, 16 - (1 + 1 + iv_len)); - nonce[15] = counter; + iv[0] = flags; + memcpy(iv + 1, nonce, CCM_STAR_NONCE_LENGTH); + iv[14] = 0; + iv[15] = counter; } /*---------------------------------------------------------------------------*/ /* XORs the block m[pos] ... m[pos + 15] with K_{counter} */ static void -ctr_step(const uint8_t *iv, uint8_t iv_len, +ctr_step(const uint8_t *nonce, uint8_t pos, uint8_t *m_and_result, uint8_t m_len, @@ -77,7 +73,7 @@ ctr_step(const uint8_t *iv, uint8_t iv_len, uint8_t a[AES_128_BLOCK_SIZE]; uint8_t i; - set_nonce(a, CCM_STAR_ENCRYPTION_FLAGS, iv, iv_len, counter); + set_nonce(a, CCM_STAR_ENCRYPTION_FLAGS, nonce, counter); AES_128.encrypt(a); for(i = 0; (pos + i < m_len) && (i < AES_128_BLOCK_SIZE); i++) { @@ -86,9 +82,9 @@ ctr_step(const uint8_t *iv, uint8_t iv_len, } /*---------------------------------------------------------------------------*/ static void -mic(const uint8_t* m, uint8_t m_len, - const uint8_t* iv, uint8_t iv_len, - const uint8_t* a, uint8_t a_len, +mic(const uint8_t *m, uint8_t m_len, + const uint8_t *nonce, + const uint8_t *a, uint8_t a_len, uint8_t *result, uint8_t mic_len) { @@ -96,10 +92,7 @@ mic(const uint8_t* m, uint8_t m_len, uint8_t pos; uint8_t i; - set_nonce(x, - CCM_STAR_AUTH_FLAGS(a_len, mic_len), - iv, iv_len, - m_len); + set_nonce(x, CCM_STAR_AUTH_FLAGS(a_len, mic_len), nonce, m_len); AES_128.encrypt(x); if(a_len > 0) { @@ -132,13 +125,13 @@ mic(const uint8_t* m, uint8_t m_len, } } - ctr_step(iv, iv_len, 0, x, AES_128_BLOCK_SIZE, 0); + ctr_step(nonce, 0, x, AES_128_BLOCK_SIZE, 0); memcpy(result, x, mic_len); } /*---------------------------------------------------------------------------*/ static void -ctr(uint8_t* m, uint8_t m_len, const uint8_t* iv, uint8_t iv_len) +ctr(uint8_t *m, uint8_t m_len, const uint8_t* nonce) { uint8_t pos; uint8_t counter; @@ -146,12 +139,12 @@ ctr(uint8_t* m, uint8_t m_len, const uint8_t* iv, uint8_t iv_len) pos = 0; counter = 1; while(pos < m_len) { - ctr_step(iv, iv_len, pos, m, m_len, counter++); + ctr_step(nonce, pos, m, m_len, counter++); pos += AES_128_BLOCK_SIZE; } } /*---------------------------------------------------------------------------*/ -static void set_key(const uint8_t* key) { +static void set_key(const uint8_t *key) { AES_128.set_key((uint8_t*)key); } /*---------------------------------------------------------------------------*/ diff --git a/core/lib/ccm-star.h b/core/lib/ccm-star.h index 90c9f7349..f0394e4ae 100644 --- a/core/lib/ccm-star.h +++ b/core/lib/ccm-star.h @@ -48,6 +48,8 @@ #define CCM_STAR ccm_star_driver #endif /* CCM_STAR_CONF */ +#define CCM_STAR_NONCE_LENGTH 13 + /** * Structure of CCM* drivers. */ @@ -57,13 +59,12 @@ struct ccm_star_driver { * \brief Generates a MIC over the data supplied. * \param data The data buffer to read. * \param data_length The data buffer length. - * \param iv The IV to use. - * \param iv_length The IV's length. + * \param nonce The nonce to use. CCM_STAR_NONCE_LENGTH bytes long. * \param result The generated MIC will be put here * \param mic_len The size of the MIC to be generated. <= 16. */ void (* mic)(const uint8_t* data, uint8_t data_length, - const uint8_t* iv, uint8_t iv_len, + const uint8_t* nonce, const uint8_t* add, uint8_t add_len, uint8_t *result, uint8_t mic_len); @@ -72,13 +73,10 @@ struct ccm_star_driver { * \brief XORs the frame in the packetbuf with the key stream. * \param data The data buffer to read. * \param data_length The data buffer length. - * \param iv The IV to use. - * \param iv_length The IV's length. - * \param mic Output buffer to hold the MIC to be generated. - * \param mic_len The size of the MIC to be generated. <= 16. + * \param nonce The nonce to use. CCM_STAR_NONCE_LENGTH bytes long. */ void (* ctr)( uint8_t* data, uint8_t data_length, - const uint8_t* iv, uint8_t iv_len); + const uint8_t* nonce); /** * \brief Sets the key in use. Default implementation calls AES_128.set_key() diff --git a/core/net/llsec/ccm-star-packetbuf.c b/core/net/llsec/ccm-star-packetbuf.c index 95bfd1528..08087398e 100644 --- a/core/net/llsec/ccm-star-packetbuf.c +++ b/core/net/llsec/ccm-star-packetbuf.c @@ -18,19 +18,19 @@ void ccm_star_mic_packetbuf(const uint8_t *extended_source_address, uint8_t data_len = packetbuf_datalen(); uint8_t *headerptr = packetbuf_hdrptr(); uint8_t header_len = packetbuf_hdrlen(); - uint8_t iv[13]; + uint8_t nonce[CCM_STAR_NONCE_LENGTH]; - memcpy(iv, extended_source_address, 8); - iv[8] = packetbuf_attr(PACKETBUF_ATTR_FRAME_COUNTER_BYTES_2_3) >> 8; - iv[9] = packetbuf_attr(PACKETBUF_ATTR_FRAME_COUNTER_BYTES_2_3) & 0xff; - iv[10] = packetbuf_attr(PACKETBUF_ATTR_FRAME_COUNTER_BYTES_0_1) >> 8; - iv[11] = packetbuf_attr(PACKETBUF_ATTR_FRAME_COUNTER_BYTES_0_1) & 0xff; - iv[12] = packetbuf_attr(PACKETBUF_ATTR_SECURITY_LEVEL); + memcpy(nonce, extended_source_address, 8); + nonce[8] = packetbuf_attr(PACKETBUF_ATTR_FRAME_COUNTER_BYTES_2_3) >> 8; + nonce[9] = packetbuf_attr(PACKETBUF_ATTR_FRAME_COUNTER_BYTES_2_3) & 0xff; + nonce[10] = packetbuf_attr(PACKETBUF_ATTR_FRAME_COUNTER_BYTES_0_1) >> 8; + nonce[11] = packetbuf_attr(PACKETBUF_ATTR_FRAME_COUNTER_BYTES_0_1) & 0xff; + nonce[12] = packetbuf_attr(PACKETBUF_ATTR_SECURITY_LEVEL); if(packetbuf_attr(PACKETBUF_ATTR_SECURITY_LEVEL) & (1 << 2)) { - CCM_STAR.mic(dataptr, data_len, iv, 13, headerptr, header_len, result, mic_len); + CCM_STAR.mic(dataptr, data_len, nonce, headerptr, header_len, result, mic_len); } else { - CCM_STAR.mic(dataptr, 0, iv, 13, headerptr, packetbuf_totlen(), result, mic_len); + CCM_STAR.mic(dataptr, 0, nonce, headerptr, packetbuf_totlen(), result, mic_len); } } /*---------------------------------------------------------------------------*/ @@ -38,15 +38,15 @@ void ccm_star_ctr_packetbuf(const uint8_t *extended_source_address) { uint8_t *dataptr = packetbuf_dataptr(); uint8_t data_len = packetbuf_datalen(); - uint8_t iv[13]; + uint8_t nonce[CCM_STAR_NONCE_LENGTH]; - memcpy(iv, extended_source_address, 8); - iv[8] = packetbuf_attr(PACKETBUF_ATTR_FRAME_COUNTER_BYTES_2_3) >> 8; - iv[9] = packetbuf_attr(PACKETBUF_ATTR_FRAME_COUNTER_BYTES_2_3) & 0xff; - iv[10] = packetbuf_attr(PACKETBUF_ATTR_FRAME_COUNTER_BYTES_0_1) >> 8; - iv[11] = packetbuf_attr(PACKETBUF_ATTR_FRAME_COUNTER_BYTES_0_1) & 0xff; - iv[12] = packetbuf_attr(PACKETBUF_ATTR_SECURITY_LEVEL); + memcpy(nonce, extended_source_address, 8); + nonce[8] = packetbuf_attr(PACKETBUF_ATTR_FRAME_COUNTER_BYTES_2_3) >> 8; + nonce[9] = packetbuf_attr(PACKETBUF_ATTR_FRAME_COUNTER_BYTES_2_3) & 0xff; + nonce[10] = packetbuf_attr(PACKETBUF_ATTR_FRAME_COUNTER_BYTES_0_1) >> 8; + nonce[11] = packetbuf_attr(PACKETBUF_ATTR_FRAME_COUNTER_BYTES_0_1) & 0xff; + nonce[12] = packetbuf_attr(PACKETBUF_ATTR_SECURITY_LEVEL); - CCM_STAR.ctr(dataptr, data_len, iv, 13); + CCM_STAR.ctr(dataptr, data_len, nonce); } /*---------------------------------------------------------------------------*/