MEDIUM: ssl/sample: add ssl_fc_sigalgs_bin sample fetch

This new sample fetch allow to extract the binary list contained in the
signature_algorithms (13) TLS extensions.

https://datatracker.ietf.org/doc/html/rfc8446#section-4.2.3
This commit is contained in:
William Lallemand 2024-08-23 20:53:24 +02:00
parent e8fecef0ff
commit d2fc1ab66e
2 changed files with 44 additions and 0 deletions

View File

@ -23167,6 +23167,7 @@ ssl_fc_server_traffic_secret_0 string
ssl_fc_server_random binary
ssl_fc_session_id binary
ssl_fc_session_key binary
ssl_fc_sigalgs_bin([<filter_option>]) binary
ssl_fc_sni string
ssl_fc_supported_versions_bin([<filter_option>]) binary
ssl_fc_use_keysize integer
@ -23884,6 +23885,16 @@ ssl_fc_session_key : binary
traffic sent using ephemeral ciphers. This requires OpenSSL >= 1.1.0, or
BoringSSL.
ssl_fc_sigalgs_bin([<filter_option>]) : binary
Returns the content of the signatures_algorithms (13) TLS extension presented
during the Client Hello. It provides a binary list of 2-bytes algorithms
defined in the TLS RFC: https://datatracker.ietf.org/doc/html/rfc8446#section-4.2.3.
This value can return only if the value "tune.ssl.capture-buffer-size" is set
greater than 0. Setting <filter_option> allows to filter returned data.
Accepted values:
0 : return the full list of ciphers (default)
1 : exclude GREASE (RFC8701) values from the output
ssl_fc_sni : string
This extracts the Server Name Indication TLS extension (SNI) field from an

View File

@ -2017,6 +2017,38 @@ smp_fetch_ssl_fc_supver_bin(const struct arg *args, struct sample *smp, const ch
return 1;
}
static int
smp_fetch_ssl_fc_sigalgs_bin(const struct arg *args, struct sample *smp, const char *kw, void *private)
{
struct buffer *smp_trash;
struct connection *conn;
struct ssl_capture *capture;
SSL *ssl;
conn = objt_conn(smp->sess->origin);
ssl = ssl_sock_get_ssl_object(conn);
if (!ssl)
return 0;
capture = SSL_get_ex_data(ssl, ssl_capture_ptr_index);
if (!capture)
return 0;
if (args[0].data.sint) {
smp_trash = get_trash_chunk();
exclude_tls_grease(capture->data + capture->sigalgs_offset, capture->sigalgs_len, smp_trash);
smp->data.u.str.area = smp_trash->area;
smp->data.u.str.data = smp_trash->data;
smp->flags = SMP_F_VOL_SESS;
smp->data.type = SMP_T_BIN;
} else {
smp->flags = SMP_F_VOL_SESS | SMP_F_CONST;
smp->data.type = SMP_T_BIN;
smp->data.u.str.area = capture->data + capture->sigalgs_offset;
smp->data.u.str.data = capture->sigalgs_len;
}
return 1;
}
static int
smp_fetch_ssl_fc_err_str(const struct arg *args, struct sample *smp, const char *kw, void *private)
@ -2522,6 +2554,7 @@ static struct sample_fetch_kw_list sample_fetch_keywords = {ILH, {
{ "ssl_fc_eclist_bin", smp_fetch_ssl_fc_ecl_bin, ARG1(0,SINT), NULL, SMP_T_STR, SMP_USE_L5CLI },
{ "ssl_fc_ecformats_bin", smp_fetch_ssl_fc_ecf_bin, 0, NULL, SMP_T_STR, SMP_USE_L5CLI },
{ "ssl_fc_supported_versions_bin", smp_fetch_ssl_fc_supver_bin, ARG1(0,SINT), NULL, SMP_T_BIN, SMP_USE_L5CLI },
{ "ssl_fc_sigalgs_bin", smp_fetch_ssl_fc_sigalgs_bin, ARG1(0,SINT), NULL, SMP_T_BIN, SMP_USE_L5CLI },
/* SSL server certificate fetches */
{ "ssl_s_der", smp_fetch_ssl_x_der, 0, NULL, SMP_T_BIN, SMP_USE_L5CLI },