From 6d73b8c57e5bd74a0e7b880d2e547cd6da3649b9 Mon Sep 17 00:00:00 2001 From: Bernhard Amann Date: Mon, 27 Jan 2014 10:22:06 -0800 Subject: [PATCH] Fix x509_extension event. The event now really returns the extension. If openssl supports printing it, it is converted into the openssl ascii output. The output does not always look pretty because it can contain newlines. New event syntax: event x509_extension(c: connection, is_orig: bool, cert:X509, extension: X509_extension_info) Example output for extension: [name=X509v3 Extended Key Usage, short_name=extendedKeyUsage, oid=2.5.29.37, critical=F, value=TLS Web Server Authentication, TLS Web Client Authentication] [name=X509v3 Certificate Policies, short_name=certificatePolicies, oid=2.5.29.32, critical=F, value=Policy: 1.3.6.1.4.1.6449.1.2.1.3.4^J CPS: https://secure.comodo.com/CPS^J] --- scripts/base/init-bare.bro | 12 ++++ src/NetVar.cc | 2 + src/NetVar.h | 1 + src/analyzer/protocol/ssl/events.bif | 6 +- src/analyzer/protocol/ssl/ssl-analyzer.pac | 61 +++++++++++++------ .../.stdout | 20 ++++++ .../base/protocols/ssl/x509_extensions.test | 7 +++ 7 files changed, 90 insertions(+), 19 deletions(-) create mode 100644 testing/btest/Baseline/scripts.base.protocols.ssl.x509_extensions/.stdout create mode 100644 testing/btest/scripts/base/protocols/ssl/x509_extensions.test diff --git a/scripts/base/init-bare.bro b/scripts/base/init-bare.bro index 8d4899b785..7f80e63f54 100644 --- a/scripts/base/init-bare.bro +++ b/scripts/base/init-bare.bro @@ -2432,6 +2432,18 @@ type X509: record { not_valid_after: time; ##< Timestamp after when certificate is not valid. }; +## An X509 extension. +## +## +## .. bro:see:: x509_extension +type X509_extension_info: record { + name: string; ##< long name of extension. oid if name not known + short_name: string &optional; ##< short name of extension if known. + oid: string; ##< oid of extension + critical: bool; ##< true if extension is critical + value: string; ##< extension content parsed to string for known extensions. Raw data otherwise. +}; + ## HTTP session statistics. ## ## .. bro:see:: http_stats diff --git a/src/NetVar.cc b/src/NetVar.cc index 79652112f3..05a4e16b47 100644 --- a/src/NetVar.cc +++ b/src/NetVar.cc @@ -48,6 +48,7 @@ int tcp_max_above_hole_without_any_acks; int tcp_excessive_data_without_further_acks; RecordType* x509_type; +RecordType* x509_extension_type; RecordType* socks_address; @@ -356,6 +357,7 @@ void init_net_var() opt_internal_int("tcp_excessive_data_without_further_acks"); x509_type = internal_type("X509")->AsRecordType(); + x509_extension_type = internal_type("X509_extension_info")->AsRecordType(); socks_address = internal_type("SOCKS::Address")->AsRecordType(); diff --git a/src/NetVar.h b/src/NetVar.h index 12949c0e55..8ef6571313 100644 --- a/src/NetVar.h +++ b/src/NetVar.h @@ -51,6 +51,7 @@ extern int tcp_max_above_hole_without_any_acks; extern int tcp_excessive_data_without_further_acks; extern RecordType* x509_type; +extern RecordType* x509_extension_type; extern RecordType* socks_address; diff --git a/src/analyzer/protocol/ssl/events.bif b/src/analyzer/protocol/ssl/events.bif index 01abb87745..7319d2ce3e 100644 --- a/src/analyzer/protocol/ssl/events.bif +++ b/src/analyzer/protocol/ssl/events.bif @@ -178,11 +178,13 @@ event x509_certificate%(c: connection, is_orig: bool, cert: X509, chain_idx: cou ## ## is_orig: True if event is raised for originator side of the connection. ## -## data: The raw data associated with the extension. +## cert: The parsed certificate. +## +## extension: The parsed extension. ## ## .. bro:see:: ssl_alert ssl_client_hello ssl_established ssl_extension ## ssl_server_hello x509_certificate x509_error x509_verify -event x509_extension%(c: connection, is_orig: bool, data: string%); +event x509_extension%(c: connection, is_orig: bool, cert: X509, extension: X509_extension_info%); ## Generated when errors occur during parsing an X509 certificate. ## diff --git a/src/analyzer/protocol/ssl/ssl-analyzer.pac b/src/analyzer/protocol/ssl/ssl-analyzer.pac index 18d3812742..0156671ce8 100644 --- a/src/analyzer/protocol/ssl/ssl-analyzer.pac +++ b/src/analyzer/protocol/ssl/ssl-analyzer.pac @@ -9,6 +9,7 @@ #include "util.h" #include +#include #include %} @@ -298,25 +299,51 @@ refine connection SSL_Conn += { int num_ext = X509_get_ext_count(pTemp); for ( int k = 0; k < num_ext; ++k ) { - unsigned char *pBuffer = 0; - int length = 0; + char name[256]; + char oid[256]; + + memset(name, 0, 256); + memset(oid, 0, 256); X509_EXTENSION* ex = X509_get_ext(pTemp, k); - if (ex) - { - ASN1_STRING *pString = X509_EXTENSION_get_data(ex); - length = ASN1_STRING_to_UTF8(&pBuffer, pString); - //i2t_ASN1_OBJECT(&pBuffer, length, obj) - // printf("extension length: %d\n", length); - // -1 indicates an error. - if ( length >= 0 ) - { - StringVal* value = new StringVal(length, (char*)pBuffer); - BifEvent::generate_x509_extension(bro_analyzer(), - bro_analyzer()->Conn(), ${rec.is_orig}, value); - } - OPENSSL_free(pBuffer); - } + + if ( !ex ) + continue; + + ASN1_OBJECT* ext_asn = X509_EXTENSION_get_object(ex); + const char* short_name = OBJ_nid2sn(OBJ_obj2nid(ext_asn)); + + OBJ_obj2txt(name, 255, ext_asn, 0); + OBJ_obj2txt(oid, 255, ext_asn, 1); + + int critical = 0; + if ( X509_EXTENSION_get_critical(ex) != 0 ) + critical = 1; + + BIO *bio = BIO_new(BIO_s_mem()); + if(!X509V3_EXT_print(bio, ex, 0, 0)) + M_ASN1_OCTET_STRING_print(bio,ex->value); + + BIO_flush(bio); + int length = BIO_pending(bio); + // use OPENSSL_malloc here. Using new or anything else can lead + // to interesting, hard to debug segfaults. + char *buffer = (char*) OPENSSL_malloc(length); + BIO_read(bio, buffer, length); + StringVal* ext_val = new StringVal(length, buffer); + BIO_free_all(bio); + OPENSSL_free(buffer); + + RecordVal* pX509Ext = new RecordVal(x509_extension_type); + pX509Ext->Assign(0, new StringVal(name)); + if ( short_name and strlen(short_name) > 0 ) + pX509Ext->Assign(1, new StringVal(short_name)); + pX509Ext->Assign(2, new StringVal(oid)); + pX509Ext->Assign(3, new Val(critical, TYPE_BOOL)); + pX509Ext->Assign(4, ext_val); + + BifEvent::generate_x509_extension(bro_analyzer(), + bro_analyzer()->Conn(), ${rec.is_orig}, pX509Cert->Ref(), pX509Ext); } } X509_free(pTemp); diff --git a/testing/btest/Baseline/scripts.base.protocols.ssl.x509_extensions/.stdout b/testing/btest/Baseline/scripts.base.protocols.ssl.x509_extensions/.stdout new file mode 100644 index 0000000000..3f9c8661bf --- /dev/null +++ b/testing/btest/Baseline/scripts.base.protocols.ssl.x509_extensions/.stdout @@ -0,0 +1,20 @@ +[name=X509v3 Authority Key Identifier, short_name=authorityKeyIdentifier, oid=2.5.29.35, critical=F, value=keyid:3F:D5:B5:D0:D6:44:79:50:4A:17:A3:9B:8C:4A:DC:B8:B0:22:64:6B^J] +[name=X509v3 Subject Key Identifier, short_name=subjectKeyIdentifier, oid=2.5.29.14, critical=F, value=A2:76:09:20:A8:40:FD:A1:AC:C8:E9:35:B9:11:A6:61:FF:8C:FF:A3] +[name=X509v3 Key Usage, short_name=keyUsage, oid=2.5.29.15, critical=T, value=Digital Signature, Key Encipherment] +[name=X509v3 Basic Constraints, short_name=basicConstraints, oid=2.5.29.19, critical=T, value=CA:FALSE] +[name=X509v3 Extended Key Usage, short_name=extendedKeyUsage, oid=2.5.29.37, critical=F, value=TLS Web Server Authentication, TLS Web Client Authentication] +[name=X509v3 Certificate Policies, short_name=certificatePolicies, oid=2.5.29.32, critical=F, value=Policy: 1.3.6.1.4.1.6449.1.2.1.3.4^J CPS: https://secure.comodo.com/CPS^J] +[name=X509v3 CRL Distribution Points, short_name=crlDistributionPoints, oid=2.5.29.31, critical=F, value=^JFull Name:^J URI:http://crl.comodoca.com/COMODOHigh-AssuranceSecureServerCA.crl^J] +[name=Authority Information Access, short_name=authorityInfoAccess, oid=1.3.6.1.5.5.7.1.1, critical=F, value=CA Issuers - URI:http://crt.comodoca.com/COMODOHigh-AssuranceSecureServerCA.crt^JOCSP - URI:http://ocsp.comodoca.com^J] +[name=X509v3 Subject Alternative Name, short_name=subjectAltName, oid=2.5.29.17, critical=F, value=DNS:*.taleo.net, DNS:taleo.net] +[name=X509v3 Authority Key Identifier, short_name=authorityKeyIdentifier, oid=2.5.29.35, critical=F, value=keyid:AD:BD:98:7A:34:B4:26:F7:FA:C4:26:54:EF:03:BD:E0:24:CB:54:1A^J] +[name=X509v3 Subject Key Identifier, short_name=subjectKeyIdentifier, oid=2.5.29.14, critical=F, value=3F:D5:B5:D0:D6:44:79:50:4A:17:A3:9B:8C:4A:DC:B8:B0:22:64:6B] +[name=X509v3 Key Usage, short_name=keyUsage, oid=2.5.29.15, critical=T, value=Certificate Sign, CRL Sign] +[name=X509v3 Basic Constraints, short_name=basicConstraints, oid=2.5.29.19, critical=T, value=CA:TRUE, pathlen:0] +[name=X509v3 Certificate Policies, short_name=certificatePolicies, oid=2.5.29.32, critical=F, value=Policy: X509v3 Any Policy^J] +[name=X509v3 CRL Distribution Points, short_name=crlDistributionPoints, oid=2.5.29.31, critical=F, value=^JFull Name:^J URI:http://crl.usertrust.com/AddTrustExternalCARoot.crl^J] +[name=Authority Information Access, short_name=authorityInfoAccess, oid=1.3.6.1.5.5.7.1.1, critical=F, value=CA Issuers - URI:http://crt.usertrust.com/AddTrustExternalCARoot.p7c^JCA Issuers - URI:http://crt.usertrust.com/AddTrustUTNSGCCA.crt^JOCSP - URI:http://ocsp.usertrust.com^J] +[name=X509v3 Subject Key Identifier, short_name=subjectKeyIdentifier, oid=2.5.29.14, critical=F, value=AD:BD:98:7A:34:B4:26:F7:FA:C4:26:54:EF:03:BD:E0:24:CB:54:1A] +[name=X509v3 Key Usage, short_name=keyUsage, oid=2.5.29.15, critical=F, value=Certificate Sign, CRL Sign] +[name=X509v3 Basic Constraints, short_name=basicConstraints, oid=2.5.29.19, critical=T, value=CA:TRUE] +[name=X509v3 Authority Key Identifier, short_name=authorityKeyIdentifier, oid=2.5.29.35, critical=F, value=keyid:AD:BD:98:7A:34:B4:26:F7:FA:C4:26:54:EF:03:BD:E0:24:CB:54:1A^JDirName:/C=SE/O=AddTrust AB/OU=AddTrust External TTP Network/CN=AddTrust External CA Root^Jserial:01^J] diff --git a/testing/btest/scripts/base/protocols/ssl/x509_extensions.test b/testing/btest/scripts/base/protocols/ssl/x509_extensions.test new file mode 100644 index 0000000000..4db3233b27 --- /dev/null +++ b/testing/btest/scripts/base/protocols/ssl/x509_extensions.test @@ -0,0 +1,7 @@ +# @TEST-EXEC: bro -r $TRACES/tls1.2.trace %INPUT +# @TEST-EXEC: btest-diff .stdout + +event x509_extension(c: connection, is_orig: bool, cert:X509, extension: X509_extension_info) +{ + print extension; +}