-
-typedef struct {
- uint8_t *data;
- size_t len;
-} buffer_t;
-
-static int buffer_next(buffer_t *b, void *out, size_t n) {
- if (b->len < n) {
- return -1;
- }
- memmove(out, b->data, n);
-
- b->data += n;
- b->len -= n;
-
- return 0;
-}
-
-static int buffer_uint16(buffer_t *b, uint16_t *out) {
- uint16_t tmp;
- if (buffer_next(b, &tmp, sizeof(tmp)) != 0)
- return -1;
-
- *out = be16toh(tmp);
- return 0;
-}
-
-#define TYPE_HOST 0x0000
-#define TYPE_TIME 0x0001
-#define TYPE_TIME_HR 0x0008
-#define TYPE_PLUGIN 0x0002
-#define TYPE_PLUGIN_INSTANCE 0x0003
-#define TYPE_TYPE 0x0004
-#define TYPE_TYPE_INSTANCE 0x0005
-#define TYPE_VALUES 0x0006
-#define TYPE_INTERVAL 0x0007
-#define TYPE_INTERVAL_HR 0x0009
-#define TYPE_SIGN_SHA256 0x0200
-#define TYPE_ENCR_AES256 0x0210
-
-static int parse_int(void *payload, size_t payload_size, uint64_t *out) {
- uint64_t tmp;
-
- if (payload_size != sizeof(tmp))
- return EINVAL;
-
- memmove(&tmp, payload, sizeof(tmp));
- *out = be64toh(tmp);
- return 0;
-}
-
-static int parse_string(void *payload, size_t payload_size, char *out,
- size_t out_size) {
- char *in = payload;
-
- if ((payload_size < 1) || (in[payload_size - 1] != 0) ||
- (payload_size > out_size))
- return EINVAL;
-
- strncpy(out, in, out_size);
- return 0;
-}
-
-static int parse_identifier(uint16_t type, void *payload, size_t payload_size,
- lcc_value_list_t *state) {
- char buf[LCC_NAME_LEN];
-
- if (parse_string(payload, payload_size, buf, sizeof(buf)) != 0)
- return EINVAL;
-
- switch (type) {
- case TYPE_HOST:
- memmove(state->identifier.host, buf, LCC_NAME_LEN);
- break;
- case TYPE_PLUGIN:
- memmove(state->identifier.plugin, buf, LCC_NAME_LEN);
- break;
- case TYPE_PLUGIN_INSTANCE:
- memmove(state->identifier.plugin_instance, buf, LCC_NAME_LEN);
- break;
- case TYPE_TYPE:
- memmove(state->identifier.type, buf, LCC_NAME_LEN);
- break;
- case TYPE_TYPE_INSTANCE:
- memmove(state->identifier.type_instance, buf, LCC_NAME_LEN);
- break;
- default:
- return EINVAL;
- }
-
- return 0;
-}
-
-static int parse_time(uint16_t type, void *payload, size_t payload_size,
- lcc_value_list_t *state) {
- uint64_t tmp = 0;
- if (parse_int(payload, payload_size, &tmp))
- return EINVAL;
-
- double t = (double)tmp;
- switch (type) {
- case TYPE_INTERVAL:
- state->interval = t;
- break;
- case TYPE_INTERVAL_HR:
- state->interval = t / 1073741824.0;
- break;
- case TYPE_TIME:
- state->time = t;
- break;
- case TYPE_TIME_HR:
- state->time = t / 1073741824.0;
- break;
- default:
- return EINVAL;
- }
-
- return 0;
-}
-
-static double ntohd(double val) /* {{{ */
-{
- static int config = 0;
-
- union {
- uint8_t byte[8];
- double floating;
- } in = {
- .floating = val,
- };
- union {
- uint8_t byte[8];
- double floating;
- } out = {
- .byte = {0},
- };
-
- if (config == 0) {
- double d = 8.642135e130;
- uint8_t b[8];
-
- memcpy(b, &d, sizeof(b));
-
- if ((b[0] == 0x2f) && (b[1] == 0x25) && (b[2] == 0xc0) && (b[3] == 0xc7) &&
- (b[4] == 0x43) && (b[5] == 0x2b) && (b[6] == 0x1f) && (b[7] == 0x5b))
- config = 1; /* need nothing */
- else if ((b[7] == 0x2f) && (b[6] == 0x25) && (b[5] == 0xc0) &&
- (b[4] == 0xc7) && (b[3] == 0x43) && (b[2] == 0x2b) &&
- (b[1] == 0x1f) && (b[0] == 0x5b))
- config = 2; /* endian flip */
- else if ((b[4] == 0x2f) && (b[5] == 0x25) && (b[6] == 0xc0) &&
- (b[7] == 0xc7) && (b[0] == 0x43) && (b[1] == 0x2b) &&
- (b[2] == 0x1f) && (b[3] == 0x5b))
- config = 3; /* int swap */
- else
- config = 4;
- }
-
- if (memcmp((char[]){0, 0, 0, 0, 0, 0, 0xf8, 0x7f}, in.byte, 8) == 0) {
- return NAN;
- } else if (config == 1) {
- return val;
- } else if (config == 2) {
- in.floating = val;
- out.byte[0] = in.byte[7];
- out.byte[1] = in.byte[6];
- out.byte[2] = in.byte[5];
- out.byte[3] = in.byte[4];
- out.byte[4] = in.byte[3];
- out.byte[5] = in.byte[2];
- out.byte[6] = in.byte[1];
- out.byte[7] = in.byte[0];
- return (out.floating);
- } else if (config == 3) {
- in.floating = val;
- out.byte[0] = in.byte[4];
- out.byte[1] = in.byte[5];
- out.byte[2] = in.byte[6];
- out.byte[3] = in.byte[7];
- out.byte[4] = in.byte[0];
- out.byte[5] = in.byte[1];
- out.byte[6] = in.byte[2];
- out.byte[7] = in.byte[3];
- return out.floating;
- } else {
- /* If in doubt, just copy the value back to the caller. */
- return val;
- }
-} /* }}} double ntohd */
-
-static int parse_values(void *payload, size_t payload_size,
- lcc_value_list_t *state) {
- buffer_t *b = &(buffer_t){
- .data = payload, .len = payload_size,
- };
-
- uint16_t n;
- if (buffer_uint16(b, &n))
- return EINVAL;
-
- if (((size_t)n * 9) != b->len)
- return EINVAL;
-
- state->values_len = (size_t)n;
- state->values = calloc(sizeof(*state->values), state->values_len);
- state->values_types = calloc(sizeof(*state->values_types), state->values_len);
- if ((state->values == NULL) || (state->values_types == NULL)) {
- free(state->values);
- free(state->values_types);
- return ENOMEM;
- }
-
- for (uint16_t i = 0; i < n; i++) {
- uint8_t tmp;
- if (buffer_next(b, &tmp, sizeof(tmp)))
- return EINVAL;
- state->values_types[i] = (int)tmp;
- }
-
- for (uint16_t i = 0; i < n; i++) {
- uint64_t tmp;
- if (buffer_next(b, &tmp, sizeof(tmp)))
- return EINVAL;
-
- if (state->values_types[i] == LCC_TYPE_GAUGE) {
- union {
- uint64_t i;
- double d;
- } conv = {.i = tmp};
- state->values[i].gauge = ntohd(conv.d);
- continue;
- }
-
- tmp = be64toh(tmp);
- switch (state->values_types[i]) {
- case LCC_TYPE_COUNTER:
- state->values[i].counter = (counter_t)tmp;
- break;
- case LCC_TYPE_DERIVE:
- state->values[i].derive = (derive_t)tmp;
- break;
- case LCC_TYPE_ABSOLUTE:
- state->values[i].absolute = (absolute_t)tmp;
- break;
- default:
- return EINVAL;
- }
- }
-
- return 0;
-}
-
-static int verify_sha256(void *payload, size_t payload_size,
- char const *username, char const *password,
- uint8_t hash_provided[32]) {
- gcry_md_hd_t hd = NULL;
-
- gcry_error_t err = gcry_md_open(&hd, GCRY_MD_SHA256, GCRY_MD_FLAG_HMAC);
- if (err != 0) {
- /* TODO(octo): use gcry_strerror(err) to create an error string. */
- return -1;
- }
-
- err = gcry_md_setkey(hd, password, strlen(password));
- if (err != 0) {
- gcry_md_close(hd);
- return -1;
- }
-
- gcry_md_write(hd, username, strlen(username));
- gcry_md_write(hd, payload, payload_size);
-
- unsigned char *hash_calculated = gcry_md_read(hd, GCRY_MD_SHA256);
- if (!hash_calculated) {
- gcry_md_close(hd);
- return -1;
- }
-
- int ret = memcmp(hash_provided, hash_calculated, 32);
-
- gcry_md_close(hd);
- hash_calculated = NULL;
-
- return !!ret;
-}
-
-static int parse_sign_sha256(void *signature, size_t signature_len,
- void *payload, size_t payload_size,
- lcc_network_parse_options_t const *opts) {
- if (opts->password_lookup == NULL) {
- /* TODO(octo): print warning */
- return network_parse(payload, payload_size, NONE, opts);
- }
-
- buffer_t *b = &(buffer_t){
- .data = signature, .len = signature_len,
- };
-
- uint8_t hash[32];
- if (buffer_next(b, hash, sizeof(hash)))
- return EINVAL;
-
- char username[b->len + 1];
- memset(username, 0, sizeof(username));
- if (buffer_next(b, username, sizeof(username) - 1)) {
- return EINVAL;
- }
-
- char const *password = opts->password_lookup(username);
- if (!password)
- return network_parse(payload, payload_size, NONE, opts);
-
- int status = verify_sha256(payload, payload_size, username, password, hash);
- if (status != 0)
- return status;
-
- return network_parse(payload, payload_size, SIGN, opts);
-}
-
-static int decrypt_aes256(buffer_t *b, void *iv, size_t iv_size,
- char const *password) {
- gcry_cipher_hd_t cipher = NULL;
-
- if (gcry_cipher_open(&cipher, GCRY_CIPHER_AES256, GCRY_CIPHER_MODE_OFB,
- /* flags = */ 0))
- return -1;
-
- uint8_t pwhash[32] = {0};
- gcry_md_hash_buffer(GCRY_MD_SHA256, pwhash, password, strlen(password));
-
- fprintf(stderr, "sizeof(iv) = %zu\n", sizeof(iv));
- if (gcry_cipher_setkey(cipher, pwhash, sizeof(pwhash)) ||
- gcry_cipher_setiv(cipher, iv, iv_size) ||
- gcry_cipher_decrypt(cipher, b->data, b->len, /* in = */ NULL,
- /* in_size = */ 0)) {
- gcry_cipher_close(cipher);
- return -1;
- }
-
- gcry_cipher_close(cipher);
- return 0;
-}
-
-static int parse_encrypt_aes256(void *data, size_t data_size,
- lcc_network_parse_options_t const *opts) {
- if (opts->password_lookup == NULL) {
- /* TODO(octo): print warning */
- return ENOENT;
- }
-
- buffer_t *b = &(buffer_t){
- .data = data, .len = data_size,
- };
-
- uint16_t username_len;
- if (buffer_uint16(b, &username_len))
- return EINVAL;
- if ((size_t)username_len > data_size)
- return ENOMEM;
- char username[((size_t)username_len) + 1];
- memset(username, 0, sizeof(username));
- if (buffer_next(b, username, sizeof(username)))
- return EINVAL;
-
- char const *password = opts->password_lookup(username);
- if (!password)
- return ENOENT;
-
- uint8_t iv[16];
- if (buffer_next(b, iv, sizeof(iv)))
- return EINVAL;
-
- int status = decrypt_aes256(b, iv, sizeof(iv), password);
- if (status != 0)
- return status;
-
- uint8_t hash_provided[20];
- if (buffer_next(b, hash_provided, sizeof(hash_provided))) {
- return -1;
- }
-
- uint8_t hash_calculated[20];
- gcry_md_hash_buffer(GCRY_MD_SHA1, hash_calculated, b->data, b->len);
-
- if (memcmp(hash_provided, hash_calculated, sizeof(hash_provided)) != 0) {
- return -1;
- }
-
- return network_parse(b->data, b->len, ENCRYPT, opts);
-}
-
-static int network_parse(void *data, size_t data_size, lcc_security_level_t sl,
- lcc_network_parse_options_t const *opts) {
- buffer_t *b = &(buffer_t){
- .data = data, .len = data_size,
- };
-
- lcc_value_list_t state = {0};
-
- while (b->len > 0) {
- uint16_t type = 0, sz = 0;
- if (buffer_uint16(b, &type) || buffer_uint16(b, &sz)) {
- DEBUG("lcc_network_parse(): reading type and/or length failed.\n");
- return EINVAL;
- }
-
- if ((sz < 5) || (((size_t)sz - 4) > b->len)) {
- DEBUG("lcc_network_parse(): invalid 'sz' field: sz = %" PRIu16
- ", b->len = %zu\n",
- sz, b->len);
- return EINVAL;
- }
- sz -= 4;
-
- uint8_t payload[sz];
- if (buffer_next(b, payload, sizeof(payload)))
- return EINVAL;
-
- switch (type) {
- case TYPE_HOST:
- case TYPE_PLUGIN:
- case TYPE_PLUGIN_INSTANCE:
- case TYPE_TYPE:
- case TYPE_TYPE_INSTANCE: {
- if (parse_identifier(type, payload, sizeof(payload), &state)) {
- DEBUG("lcc_network_parse(): parse_identifier failed.\n");
- return EINVAL;
- }
- break;
- }
-
- case TYPE_INTERVAL:
- case TYPE_INTERVAL_HR:
- case TYPE_TIME:
- case TYPE_TIME_HR: {
- if (parse_time(type, payload, sizeof(payload), &state)) {
- DEBUG("lcc_network_parse(): parse_time failed.\n");
- return EINVAL;
- }
- break;
- }
-
- case TYPE_VALUES: {
- lcc_value_list_t vl = state;
- if (parse_values(payload, sizeof(payload), &vl)) {
- DEBUG("lcc_network_parse(): parse_values failed.\n");
- return EINVAL;
- }
-
- /* TODO(octo): skip if current_security_level < required_security_level */
-
- int status = opts->writer(&vl);
-
- free(vl.values);
- free(vl.values_types);
-
- if (status != 0)
- return status;
- break;
- }
-
- case TYPE_SIGN_SHA256: {
- int status =
- parse_sign_sha256(payload, sizeof(payload), b->data, b->len, opts);
- if (status != 0) {
- DEBUG("lcc_network_parse(): parse_sign_sha256() = %d\n", status);
- return -1;
- }
- /* parse_sign_sha256, if successful, consumes all remaining data. */
- b->data = NULL;
- b->len = 0;
- break;
- }
-
- case TYPE_ENCR_AES256: {
- int status = parse_encrypt_aes256(payload, sizeof(payload), opts);
- if (status != 0) {
- DEBUG("lcc_network_parse(): parse_encrypt_aes256() = %d\n", status);
- return -1;
- }
- break;
- }
-
- default: {
- DEBUG("lcc_network_parse(): ignoring unknown type %" PRIu16 "\n", type);
- return EINVAL;
- }
- }
- }
-
- return 0;
-}
-
-int lcc_network_parse(void *data, size_t data_size,
- lcc_network_parse_options_t opts) {
- if (opts.password_lookup) {
- int status;
- if ((status = init_gcrypt())) {
- return status;
- }
- }
-
- return network_parse(data, data_size, NONE, &opts);
-}