diff options
Diffstat (limited to 'third_party/srtp/crypto/cipher/aes_icm.c')
| -rw-r--r-- | third_party/srtp/crypto/cipher/aes_icm.c | 155 |
1 files changed, 118 insertions, 37 deletions
diff --git a/third_party/srtp/crypto/cipher/aes_icm.c b/third_party/srtp/crypto/cipher/aes_icm.c index e7e8c599..3d97e2ba 100644 --- a/third_party/srtp/crypto/cipher/aes_icm.c +++ b/third_party/srtp/crypto/cipher/aes_icm.c @@ -9,7 +9,7 @@ /* * - * Copyright (c) 2001-2006, Cisco Systems, Inc. + * Copyright (c) 2001-2006,2013 Cisco Systems, Inc. * All rights reserved. * * Redistribution and use in source and binary forms, with or without @@ -43,6 +43,9 @@ * */ +#ifdef HAVE_CONFIG_H + #include <config.h> +#endif #define ALIGN_32 0 @@ -101,12 +104,13 @@ aes_icm_alloc_ismacryp(cipher_t **c, int key_len, int forIsmacryp) { /* * Ismacryp, for example, uses 16 byte key + 8 byte * salt so this function is called with key_len = 24. - * The check for key_len = 30 does not apply. Our usage + * The check for key_len = 30/38/46 does not apply. Our usage * of aes functions with key_len = values other than 30 * has not broken anything. Don't know what would be the * effect of skipping this check for srtp in general. */ - if (!forIsmacryp && key_len != 30) + if (!(forIsmacryp && key_len > 16 && key_len < 30) && + key_len != 30 && key_len != 38 && key_len != 46) return err_status_bad_param; /* allocate memory a cipher of type aes_icm */ @@ -117,6 +121,17 @@ aes_icm_alloc_ismacryp(cipher_t **c, int key_len, int forIsmacryp) { /* set pointers */ *c = (cipher_t *)pointer; + switch (key_len) { + case 46: + (*c)->algorithm = AES_256_ICM; + break; + case 38: + (*c)->algorithm = AES_192_ICM; + break; + default: + (*c)->algorithm = AES_128_ICM; + break; + } (*c)->type = &aes_icm; (*c)->state = pointer + sizeof(cipher_t); @@ -162,30 +177,44 @@ aes_icm_dealloc(cipher_t *c) { */ err_status_t -aes_icm_context_init(aes_icm_ctx_t *c, const uint8_t *key) { - v128_t tmp_key; - - /* set counter and initial values to 'offset' value */ - /* FIX!!! this assumes the salt is at key + 16, and thus that the */ - /* FIX!!! cipher key length is 16! Also note this copies past the - end of the 'key' array by 2 bytes! */ - v128_copy_octet_string(&c->counter, key + 16); - v128_copy_octet_string(&c->offset, key + 16); - - /* force last two octets of the offset to zero (for srtp compatibility) */ - c->offset.v8[14] = c->offset.v8[15] = 0; - c->counter.v8[14] = c->counter.v8[15] = 0; - - /* set tmp_key (for alignment) */ - v128_copy_octet_string(&tmp_key, key); +aes_icm_context_init(aes_icm_ctx_t *c, const uint8_t *key, int key_len) { + err_status_t status; + int base_key_len, copy_len; + + if (key_len > 16 && key_len < 30) /* Ismacryp */ + base_key_len = 16; + else if (key_len == 30 || key_len == 38 || key_len == 46) + base_key_len = key_len - 14; + else + return err_status_bad_param; + + /* + * set counter and initial values to 'offset' value, being careful not to + * go past the end of the key buffer + */ + v128_set_to_zero(&c->counter); + v128_set_to_zero(&c->offset); + + copy_len = key_len - base_key_len; + /* force last two octets of the offset to be left zero (for srtp compatibility) */ + if (copy_len > 14) + copy_len = 14; + + memcpy(&c->counter, key + base_key_len, copy_len); + memcpy(&c->offset, key + base_key_len, copy_len); debug_print(mod_aes_icm, - "key: %s", v128_hex_string(&tmp_key)); + "key: %s", octet_string_hex_string(key, base_key_len)); debug_print(mod_aes_icm, "offset: %s", v128_hex_string(&c->offset)); /* expand key */ - aes_expand_encryption_key(&tmp_key, c->expanded_key); + status = aes_expand_encryption_key(key, base_key_len, &c->expanded_key); + if (status) { + v128_set_to_zero(&c->counter); + v128_set_to_zero(&c->offset); + return status; + } /* indicate that the keystream_buffer is empty */ c->bytes_in_buffer = 0; @@ -210,7 +239,7 @@ aes_icm_set_octet(aes_icm_ctx_t *c, ((high32(octet_num) & 0x0f)<<(32-4)) | (low32(octet_num) >> 4)); #else - int tail_num = octet_num % 16; + int tail_num = (int)(octet_num % 16); uint64_t block_num = octet_num / 16; #endif @@ -231,7 +260,7 @@ aes_icm_set_octet(aes_icm_ctx_t *c, /* fill keystream buffer, if needed */ if (tail_num) { v128_copy(&c->keystream_buffer, &c->counter); - aes_encrypt(&c->keystream_buffer, c->expanded_key); + aes_encrypt(&c->keystream_buffer, &c->expanded_key); c->bytes_in_buffer = sizeof(v128_t); debug_print(mod_aes_icm, "counter: %s", @@ -257,13 +286,16 @@ aes_icm_set_octet(aes_icm_ctx_t *c, */ err_status_t -aes_icm_set_iv(aes_icm_ctx_t *c, void *iv) { - v128_t *nonce = (v128_t *) iv; +aes_icm_set_iv(aes_icm_ctx_t *c, void *iv, int direction) { + v128_t nonce; + + /* set nonce (for alignment) */ + v128_copy_octet_string(&nonce, iv); debug_print(mod_aes_icm, - "setting iv: %s", v128_hex_string(nonce)); + "setting iv: %s", v128_hex_string(&nonce)); - v128_xor(&c->counter, &c->offset, nonce); + v128_xor(&c->counter, &c->offset, &nonce); debug_print(mod_aes_icm, "set_counter: %s", v128_hex_string(&c->counter)); @@ -287,7 +319,7 @@ static inline void aes_icm_advance_ismacryp(aes_icm_ctx_t *c, uint8_t forIsmacryp) { /* fill buffer with new keystream */ v128_copy(&c->keystream_buffer, &c->counter); - aes_encrypt(&c->keystream_buffer, c->expanded_key); + aes_encrypt(&c->keystream_buffer, &c->expanded_key); c->bytes_in_buffer = sizeof(v128_t); debug_print(mod_aes_icm, "counter: %s", @@ -301,18 +333,14 @@ aes_icm_advance_ismacryp(aes_icm_ctx_t *c, uint8_t forIsmacryp) { uint32_t temp; //alex's clock counter forward temp = ntohl(c->counter.v32[3]); - c->counter.v32[3] = htonl(++temp); + ++temp; + c->counter.v32[3] = htonl(temp); } else { if (!++(c->counter.v8[15])) ++(c->counter.v8[14]); } } -inline void aes_icm_advance(aes_icm_ctx_t *c) { - aes_icm_advance_ismacryp(c, 0); -} - - /*e * icm_encrypt deals with the following cases: * @@ -440,7 +468,7 @@ aes_icm_encrypt(aes_icm_ctx_t *c, unsigned char *buf, unsigned int *enc_len) { } err_status_t -aes_icm_output(aes_icm_ctx_t *c, uint8_t *buffer, int num_octets_to_output) { +aes_icm_output(aes_icm_ctx_t *c, uint8_t *buffer, unsigned int num_octets_to_output) { unsigned int len = num_octets_to_output; /* zeroize the buffer */ @@ -450,6 +478,10 @@ aes_icm_output(aes_icm_ctx_t *c, uint8_t *buffer, int num_octets_to_output) { return aes_icm_encrypt(c, buffer, &len); } +uint16_t +aes_icm_bytes_encrypted(aes_icm_ctx_t *c) { + return htons(c->counter.v16[7]); +} char aes_icm_description[] = "aes integer counter mode"; @@ -488,9 +520,55 @@ cipher_test_case_t aes_icm_test_case_0 = { aes_icm_test_case_0_plaintext, /* plaintext */ 32, /* octets in ciphertext */ aes_icm_test_case_0_ciphertext, /* ciphertext */ + 0, + NULL, + 0, NULL /* pointer to next testcase */ }; +uint8_t aes_icm_test_case_1_key[46] = { + 0x57, 0xf8, 0x2f, 0xe3, 0x61, 0x3f, 0xd1, 0x70, + 0xa8, 0x5e, 0xc9, 0x3c, 0x40, 0xb1, 0xf0, 0x92, + 0x2e, 0xc4, 0xcb, 0x0d, 0xc0, 0x25, 0xb5, 0x82, + 0x72, 0x14, 0x7c, 0xc4, 0x38, 0x94, 0x4a, 0x98, + 0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, + 0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd +}; + +uint8_t aes_icm_test_case_1_nonce[16] = { + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 +}; + +uint8_t aes_icm_test_case_1_plaintext[32] = { + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, +}; + +uint8_t aes_icm_test_case_1_ciphertext[32] = { + 0x92, 0xbd, 0xd2, 0x8a, 0x93, 0xc3, 0xf5, 0x25, + 0x11, 0xc6, 0x77, 0xd0, 0x8b, 0x55, 0x15, 0xa4, + 0x9d, 0xa7, 0x1b, 0x23, 0x78, 0xa8, 0x54, 0xf6, + 0x70, 0x50, 0x75, 0x6d, 0xed, 0x16, 0x5b, 0xac +}; + +cipher_test_case_t aes_icm_test_case_1 = { + 46, /* octets in key */ + aes_icm_test_case_1_key, /* key */ + aes_icm_test_case_1_nonce, /* packet index */ + 32, /* octets in plaintext */ + aes_icm_test_case_1_plaintext, /* plaintext */ + 32, /* octets in ciphertext */ + aes_icm_test_case_1_ciphertext, /* ciphertext */ + 0, + NULL, + 0, + &aes_icm_test_case_0 /* pointer to next testcase */ +}; + + /* * note: the encrypt function is identical to the decrypt function @@ -500,12 +578,15 @@ cipher_type_t aes_icm = { (cipher_alloc_func_t) aes_icm_alloc, (cipher_dealloc_func_t) aes_icm_dealloc, (cipher_init_func_t) aes_icm_context_init, + (cipher_set_aad_func_t) 0, (cipher_encrypt_func_t) aes_icm_encrypt, (cipher_decrypt_func_t) aes_icm_encrypt, (cipher_set_iv_func_t) aes_icm_set_iv, + (cipher_get_tag_func_t) 0, (char *) aes_icm_description, (int) 0, /* instance count */ - (cipher_test_case_t *) &aes_icm_test_case_0, - (debug_module_t *) &mod_aes_icm + (cipher_test_case_t *) &aes_icm_test_case_1, + (debug_module_t *) &mod_aes_icm, + (cipher_type_id_t) AES_ICM }; 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