From 04f9c19c98aed91d96afa377557da86e04db6b44 Mon Sep 17 00:00:00 2001 From: Greg Hudson Date: Tue, 16 Apr 2013 13:32:04 -0400 Subject: Correct IAKERB protocol implementation The initial implementation of IAKERB in MIT krb5 mistakenly used draft-zhu-ws-kerb instead of draft-kitten-ietf-iakerb, and additionally used the wrong ASN.1 tag value for the target-realm field of the IAKERB-HEADER sequence. Correct the following aspects of the protocol implementation: * Require and use framing on all messages, not just the initial context token. * Use extension value 2 for the finish message instead of 1. * Use key usage value 41 instead of 42 for the finish message checksum. * Use UTF8String (12) for target-realm instead of OCTET STRING (4). With these changes, the IAKERB implementation is interoperable with other krb5 implementations, but not with the implementation before these changes. ticket: 9123 (new) --- doc/appdev/refs/macros/index.rst | 1 + src/include/krb5/krb5.hin | 1 + src/lib/gssapi/krb5/accept_sec_context.c | 2 +- src/lib/gssapi/krb5/gssapiP_krb5.h | 2 +- src/lib/gssapi/krb5/iakerb.c | 45 +++++++++----------------------- src/lib/gssapi/krb5/init_sec_context.c | 2 +- src/lib/krb5/asn.1/asn1_k_encode.c | 2 +- src/tests/asn.1/krb5_decode_test.c | 2 +- src/tests/asn.1/reference_encode.out | 2 +- src/tests/asn.1/trval.c | 4 ++- src/tests/asn.1/trval_reference.out | 7 ++--- 11 files changed, 26 insertions(+), 44 deletions(-) diff --git a/doc/appdev/refs/macros/index.rst b/doc/appdev/refs/macros/index.rst index ee9fe2c..645b59f 100644 --- a/doc/appdev/refs/macros/index.rst +++ b/doc/appdev/refs/macros/index.rst @@ -178,6 +178,7 @@ Public KRB5_KEYUSAGE_GSS_TOK_MIC.rst KRB5_KEYUSAGE_GSS_TOK_WRAP_INTEG.rst KRB5_KEYUSAGE_GSS_TOK_WRAP_PRIV.rst + KRB5_KEYUSAGE_FINISHED.rst KRB5_KEYUSAGE_IAKERB_FINISHED.rst KRB5_KEYUSAGE_KDC_REP_TICKET.rst KRB5_KEYUSAGE_KRB_CRED_ENCPART.rst diff --git a/src/include/krb5/krb5.hin b/src/include/krb5/krb5.hin index 7496383..7c4fc10 100644 --- a/src/include/krb5/krb5.hin +++ b/src/include/krb5/krb5.hin @@ -977,6 +977,7 @@ krb5_c_keyed_checksum_types(krb5_context context, krb5_enctype enctype, #define KRB5_KEYUSAGE_PA_REFERRAL 26 #define KRB5_KEYUSAGE_AD_SIGNEDPATH -21 +#define KRB5_KEYUSAGE_FINISHED 41 #define KRB5_KEYUSAGE_IAKERB_FINISHED 42 #define KRB5_KEYUSAGE_PA_PKINIT_KX 44 #define KRB5_KEYUSAGE_PA_OTP_REQUEST 45 /**< See RFC 6560 section 4.2 */ diff --git a/src/lib/gssapi/krb5/accept_sec_context.c b/src/lib/gssapi/krb5/accept_sec_context.c index 227aa54..c224ee9 100644 --- a/src/lib/gssapi/krb5/accept_sec_context.c +++ b/src/lib/gssapi/krb5/accept_sec_context.c @@ -378,7 +378,7 @@ kg_process_extension(krb5_context context, assert(exts != NULL); switch (ext_type) { - case KRB5_GSS_EXTS_IAKERB_FINISHED: + case GSS_EXTS_FINISHED: if (exts->iakerb.conv == NULL) { code = KRB5KRB_AP_ERR_MSG_TYPE; /* XXX */ } else { diff --git a/src/lib/gssapi/krb5/gssapiP_krb5.h b/src/lib/gssapi/krb5/gssapiP_krb5.h index 7364607..0ebe3a6 100644 --- a/src/lib/gssapi/krb5/gssapiP_krb5.h +++ b/src/lib/gssapi/krb5/gssapiP_krb5.h @@ -1291,7 +1291,7 @@ data_to_gss(krb5_data *input_k5data, gss_buffer_t output_buffer) return code; } -#define KRB5_GSS_EXTS_IAKERB_FINISHED 1 +#define GSS_EXTS_FINISHED 2 /* Credential store extensions */ diff --git a/src/lib/gssapi/krb5/iakerb.c b/src/lib/gssapi/krb5/iakerb.c index 3ee926e..9e8bc05 100644 --- a/src/lib/gssapi/krb5/iakerb.c +++ b/src/lib/gssapi/krb5/iakerb.c @@ -97,8 +97,8 @@ iakerb_make_finished(krb5_context context, if (key == NULL) return KRB5KDC_ERR_NULL_KEY; - code = krb5_k_make_checksum(context, 0, key, KRB5_KEYUSAGE_IAKERB_FINISHED, - conv, &iaf.checksum); + code = krb5_k_make_checksum(context, 0, key, KRB5_KEYUSAGE_FINISHED, conv, + &iaf.checksum); if (code != 0) return code; @@ -129,8 +129,8 @@ iakerb_verify_finished(krb5_context context, if (code != 0) return code; - code = krb5_k_verify_checksum(context, key, KRB5_KEYUSAGE_IAKERB_FINISHED, - conv, &iaf->checksum, &valid); + code = krb5_k_verify_checksum(context, key, KRB5_KEYUSAGE_FINISHED, conv, + &iaf->checksum, &valid); if (code == 0 && valid == FALSE) code = KRB5KRB_AP_ERR_BAD_INTEGRITY; @@ -163,7 +163,6 @@ iakerb_save_token(iakerb_ctx_id_t ctx, const gss_buffer_t token) */ static krb5_error_code iakerb_parse_token(iakerb_ctx_id_t ctx, - int initialContextToken, const gss_buffer_t token, krb5_data *realm, krb5_data **cookie, @@ -173,7 +172,6 @@ iakerb_parse_token(iakerb_ctx_id_t ctx, krb5_iakerb_header *iah = NULL; unsigned int bodysize; uint8_t *body; - int flags = 0; krb5_data data; struct k5input in, seq; @@ -182,12 +180,10 @@ iakerb_parse_token(iakerb_ctx_id_t ctx, goto cleanup; } - if (initialContextToken) - flags |= G_VFY_TOKEN_HDR_WRAPPER_REQUIRED; - body = token->value; code = g_verify_token_header(gss_mech_iakerb, &bodysize, &body, - IAKERB_TOK_PROXY, token->length, flags); + IAKERB_TOK_PROXY, token->length, + G_VFY_TOKEN_HDR_WRAPPER_REQUIRED); if (code != 0) goto cleanup; @@ -232,7 +228,6 @@ iakerb_make_token(iakerb_ctx_id_t ctx, krb5_data *realm, krb5_data *cookie, krb5_data *request, - int initialContextToken, gss_buffer_t token) { krb5_error_code code; @@ -269,11 +264,7 @@ iakerb_make_token(iakerb_ctx_id_t ctx, memcpy(data->data + data->length, request->data, request->length); data->length += request->length; - if (initialContextToken) - tokenSize = g_token_size(gss_mech_iakerb, data->length); - else - tokenSize = 2 + data->length; - + tokenSize = g_token_size(gss_mech_iakerb, data->length); token->value = gssalloc_malloc(tokenSize); if (token->value == NULL) { code = ENOMEM; @@ -282,12 +273,7 @@ iakerb_make_token(iakerb_ctx_id_t ctx, token->length = tokenSize; k5_buf_init_fixed(&buf, token->value, token->length); - if (initialContextToken) { - g_make_token_header(&buf, gss_mech_iakerb, data->length, - IAKERB_TOK_PROXY); - } else { - k5_buf_add_uint16_be(&buf, IAKERB_TOK_PROXY); - } + g_make_token_header(&buf, gss_mech_iakerb, data->length, IAKERB_TOK_PROXY); k5_buf_add_len(&buf, data->data, data->length); assert(buf.len == token->length); @@ -305,7 +291,6 @@ cleanup: */ static krb5_error_code iakerb_acceptor_step(iakerb_ctx_id_t ctx, - int initialContextToken, const gss_buffer_t input_token, gss_buffer_t output_token) { @@ -324,8 +309,7 @@ iakerb_acceptor_step(iakerb_ctx_id_t ctx, goto cleanup; } - code = iakerb_parse_token(ctx, initialContextToken, input_token, &realm, - NULL, &request); + code = iakerb_parse_token(ctx, input_token, &realm, NULL, &request); if (code != 0) goto cleanup; @@ -374,7 +358,7 @@ iakerb_acceptor_step(iakerb_ctx_id_t ctx, } else if (code != 0) goto cleanup; - code = iakerb_make_token(ctx, &realm, NULL, &reply, 0, output_token); + code = iakerb_make_token(ctx, &realm, NULL, &reply, output_token); if (code != 0) goto cleanup; @@ -524,7 +508,7 @@ iakerb_initiator_step(iakerb_ctx_id_t ctx, output_token->value = NULL; if (input_token != GSS_C_NO_BUFFER && input_token->length > 0) { - code = iakerb_parse_token(ctx, 0, input_token, NULL, &cookie, &in); + code = iakerb_parse_token(ctx, input_token, NULL, &cookie, &in); if (code != 0) goto cleanup; @@ -593,9 +577,7 @@ iakerb_initiator_step(iakerb_ctx_id_t ctx, if (out.length != 0) { assert(ctx->state != IAKERB_AP_REQ); - code = iakerb_make_token(ctx, &realm, cookie, &out, - (input_token == GSS_C_NO_BUFFER), - output_token); + code = iakerb_make_token(ctx, &realm, cookie, &out, output_token); if (code != 0) goto cleanup; @@ -788,8 +770,7 @@ iakerb_gss_accept_sec_context(OM_uint32 *minor_status, major_status = GSS_S_DEFECTIVE_TOKEN; goto cleanup; } - code = iakerb_acceptor_step(ctx, initialContextToken, - input_token, output_token); + code = iakerb_acceptor_step(ctx, input_token, output_token); if (code == (OM_uint32)KRB5_BAD_MSIZE) major_status = GSS_S_DEFECTIVE_TOKEN; if (code != 0) diff --git a/src/lib/gssapi/krb5/init_sec_context.c b/src/lib/gssapi/krb5/init_sec_context.c index 3cc9d4c..0a088c5 100644 --- a/src/lib/gssapi/krb5/init_sec_context.c +++ b/src/lib/gssapi/krb5/init_sec_context.c @@ -339,7 +339,7 @@ make_gss_checksum (krb5_context context, krb5_auth_context auth_context, k5_buf_add_len(&buf, credmsg.data, credmsg.length); } if (data->exts->iakerb.conv != NULL) { - k5_buf_add_uint32_be(&buf, KRB5_GSS_EXTS_IAKERB_FINISHED); + k5_buf_add_uint32_be(&buf, GSS_EXTS_FINISHED); k5_buf_add_uint32_be(&buf, finished->length); k5_buf_add_len(&buf, finished->data, finished->length); } diff --git a/src/lib/krb5/asn.1/asn1_k_encode.c b/src/lib/krb5/asn.1/asn1_k_encode.c index 5378b5c..ad5a18a 100644 --- a/src/lib/krb5/asn.1/asn1_k_encode.c +++ b/src/lib/krb5/asn.1/asn1_k_encode.c @@ -1092,7 +1092,7 @@ DEFOPTIONALEMPTYTYPE(opt_ptr_seqof_princ_plus_realm, ptr_seqof_princ_plus_realm); /* First context tag is 1, not 0. */ -DEFFIELD(iakerb_header_1, krb5_iakerb_header, target_realm, 1, ostring_data); +DEFFIELD(iakerb_header_1, krb5_iakerb_header, target_realm, 1, utf8_data); DEFFIELD(iakerb_header_2, krb5_iakerb_header, cookie, 2, opt_ostring_data_ptr); static const struct atype_info *iakerb_header_fields[] = { &k5_atype_iakerb_header_1, &k5_atype_iakerb_header_2 diff --git a/src/tests/asn.1/krb5_decode_test.c b/src/tests/asn.1/krb5_decode_test.c index 2fa6dce..391bf0f 100644 --- a/src/tests/asn.1/krb5_decode_test.c +++ b/src/tests/asn.1/krb5_decode_test.c @@ -1001,7 +1001,7 @@ main(int argc, char **argv) /* decode_iakerb_header */ { setup(krb5_iakerb_header,ktest_make_sample_iakerb_header); - decode_run("iakerb_header","","30 18 A1 0A 04 08 6B 72 62 35 64 61 74 61 A2 0A 04 08 6B 72 62 35 64 61 74 61",decode_krb5_iakerb_header,ktest_equal_iakerb_header,krb5_free_iakerb_header); + decode_run("iakerb_header","","30 18 A1 0A 0C 08 6B 72 62 35 64 61 74 61 A2 0A 04 08 6B 72 62 35 64 61 74 61",decode_krb5_iakerb_header,ktest_equal_iakerb_header,krb5_free_iakerb_header); ktest_empty_iakerb_header(&ref); } diff --git a/src/tests/asn.1/reference_encode.out b/src/tests/asn.1/reference_encode.out index faa3dba..20c6ce1 100644 --- a/src/tests/asn.1/reference_encode.out +++ b/src/tests/asn.1/reference_encode.out @@ -55,7 +55,7 @@ encode_krb5_enc_sam_response_enc_2: 30 1F A0 03 02 01 58 A1 18 04 16 65 6E 63 5F encode_krb5_pa_for_user: 30 4B A0 1A 30 18 A0 03 02 01 01 A1 11 30 0F 1B 06 68 66 74 73 61 69 1B 05 65 78 74 72 61 A1 10 1B 0E 41 54 48 45 4E 41 2E 4D 49 54 2E 45 44 55 A2 0F 30 0D A0 03 02 01 01 A1 06 04 04 31 32 33 34 A3 0A 1B 08 6B 72 62 35 64 61 74 61 encode_krb5_pa_s4u_x509_user: 30 68 A0 55 30 53 A0 06 02 04 00 CA 14 9A A1 1A 30 18 A0 03 02 01 01 A1 11 30 0F 1B 06 68 66 74 73 61 69 1B 05 65 78 74 72 61 A2 10 1B 0E 41 54 48 45 4E 41 2E 4D 49 54 2E 45 44 55 A3 12 04 10 70 61 5F 73 34 75 5F 78 35 30 39 5F 75 73 65 72 A4 07 03 05 00 80 00 00 00 A1 0F 30 0D A0 03 02 01 01 A1 06 04 04 31 32 33 34 encode_krb5_ad_kdcissued: 30 65 A0 0F 30 0D A0 03 02 01 01 A1 06 04 04 31 32 33 34 A1 10 1B 0E 41 54 48 45 4E 41 2E 4D 49 54 2E 45 44 55 A2 1A 30 18 A0 03 02 01 01 A1 11 30 0F 1B 06 68 66 74 73 61 69 1B 05 65 78 74 72 61 A3 24 30 22 30 0F A0 03 02 01 01 A1 08 04 06 66 6F 6F 62 61 72 30 0F A0 03 02 01 01 A1 08 04 06 66 6F 6F 62 61 72 -encode_krb5_iakerb_header: 30 18 A1 0A 04 08 6B 72 62 35 64 61 74 61 A2 0A 04 08 6B 72 62 35 64 61 74 61 +encode_krb5_iakerb_header: 30 18 A1 0A 0C 08 6B 72 62 35 64 61 74 61 A2 0A 04 08 6B 72 62 35 64 61 74 61 encode_krb5_iakerb_finished: 30 11 A1 0F 30 0D A0 03 02 01 01 A1 06 04 04 31 32 33 34 encode_krb5_fast_response: 30 81 9F A0 26 30 24 30 10 A1 03 02 01 0D A2 09 04 07 70 61 2D 64 61 74 61 30 10 A1 03 02 01 0D A2 09 04 07 70 61 2D 64 61 74 61 A1 13 30 11 A0 03 02 01 01 A1 0A 04 08 31 32 33 34 35 36 37 38 A2 5B 30 59 A0 11 18 0F 31 39 39 34 30 36 31 30 30 36 30 33 31 37 5A A1 05 02 03 01 E2 40 A2 10 1B 0E 41 54 48 45 4E 41 2E 4D 49 54 2E 45 44 55 A3 1A 30 18 A0 03 02 01 01 A1 11 30 0F 1B 06 68 66 74 73 61 69 1B 05 65 78 74 72 61 A4 0F 30 0D A0 03 02 01 01 A1 06 04 04 31 32 33 34 A3 03 02 01 2A encode_krb5_pa_fx_fast_reply: A0 29 30 27 A0 25 30 23 A0 03 02 01 00 A1 03 02 01 05 A2 17 04 15 6B 72 62 41 53 4E 2E 31 20 74 65 73 74 20 6D 65 73 73 61 67 65 diff --git a/src/tests/asn.1/trval.c b/src/tests/asn.1/trval.c index e0e58cc..f84c515 100644 --- a/src/tests/asn.1/trval.c +++ b/src/tests/asn.1/trval.c @@ -72,6 +72,7 @@ #define PRIM_REAL 0x09 /* Real */ #define PRIM_ENUM 0x0a /* Enumerated type */ #define PRIM_ENCR 0x0b /* Encrypted */ +#define PRIM_UTF8 0x0c /* UTF8String */ #define CONS_SEQ 0x10 /* SEQUENCE/SEQUENCE OF */ #define CONS_SET 0x11 /* SET/SET OF */ #define DEFN_NUMS 0x12 /* Numeric String */ @@ -321,7 +322,7 @@ do_prim_string(FILE *fp, int tag, unsigned char *enc, int len, int lev) /* * Only try this printing function with "reasonable" types */ - if ((tag < DEFN_NUMS) && (tag != PRIM_OCTS)) + if ((tag < DEFN_NUMS) && (tag != PRIM_OCTS) && (tag != PRIM_UTF8)) return 0; for (i=0; i < len; i++) @@ -433,6 +434,7 @@ struct typestring_table univ_types[] = { { PRIM_REAL, -1, "Real"}, { PRIM_ENUM, -1, "Enumerated type"}, { PRIM_ENCR, -1, "Encrypted"}, + { PRIM_UTF8, -1, "UTF8String"}, { CONS_SEQ, -1, "Sequence/Sequence Of"}, { CONS_SET, -1, "Set/Set Of"}, { DEFN_NUMS, -1, "Numeric String"}, diff --git a/src/tests/asn.1/trval_reference.out b/src/tests/asn.1/trval_reference.out index 9bedad4..29f88c5 100644 --- a/src/tests/asn.1/trval_reference.out +++ b/src/tests/asn.1/trval_reference.out @@ -1254,7 +1254,7 @@ encode_krb5_ad_kdcissued: encode_krb5_iakerb_header: [Sequence/Sequence Of] -. [1] [Octet String] "krb5data" +. [1] [UTF8String] "krb5data" . [2] [Octet String] "krb5data" encode_krb5_iakerb_finished: @@ -1417,10 +1417,7 @@ encode_krb5_pa_otp_req: 02 . . [11] <9> 79 6f 75 72 74 6f 6b 65 6e yourtoken -. [12] <40> - 75 72 6e 3a 69 65 74 66 3a 70 61 72 61 6d 73 3a urn:ietf:params: - 78 6d 6c 3a 6e 73 3a 6b 65 79 70 72 6f 76 3a 70 xml:ns:keyprov:p - 73 6b 63 3a 68 6f 74 70 skc:hotp +. [12] "urn:ietf:params:xml:ns:keyprov:pskc:hotp" . [13] <11> 45 78 61 6d 70 6c 65 63 6f 72 70 Examplecorp -- cgit v1.1