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56 #include "gssapiP_eap.h"
59 gssEapWrapOrGetMIC(OM_uint32 *minor,
63 gss_iov_buffer_desc *iov,
65 enum gss_eap_token_type toktype)
67 krb5_error_code code = 0;
68 gss_iov_buffer_t header;
69 gss_iov_buffer_t padding;
70 gss_iov_buffer_t trailer;
71 unsigned char acceptor_flag;
72 unsigned char *outbuf = NULL;
73 unsigned char *tbuf = NULL;
76 unsigned int gss_headerlen, gss_trailerlen;
77 size_t data_length, assoc_data_length;
79 if (!CTX_IS_ESTABLISHED(ctx)) {
80 return GSS_S_NO_CONTEXT;
83 acceptor_flag = CTX_IS_INITIATOR(ctx) ? 0 : TOK_FLAG_SENDER_IS_ACCEPTOR;
84 key_usage = ((toktype == TOK_TYPE_WRAP)
85 ? (CTX_IS_INITIATOR(ctx)
86 ? KRB_USAGE_INITIATOR_SEAL
87 : KRB_USAGE_ACCEPTOR_SEAL)
88 : (CTX_IS_INITIATOR(ctx)
89 ? KRB_USAGE_INITIATOR_SIGN
90 : KRB_USAGE_ACCEPTOR_SIGN));
92 gssEapIovMessageLength(iov, iov_count, &data_length, &assoc_data_length);
94 header = gssEapLocateIov(iov, iov_count, GSS_IOV_BUFFER_TYPE_HEADER);
100 padding = gssEapLocateIov(iov, iov_count, GSS_IOV_BUFFER_TYPE_PADDING);
102 padding->buffer.length = 0;
104 trailer = gssEapLocateIov(iov, iov_count, GSS_IOV_BUFFER_TYPE_TRAILER);
106 if (toktype == TOK_TYPE_WRAP && conf_req_flag) {
107 unsigned int k5_headerlen, k5_trailerlen, k5_padlen;
109 size_t conf_data_length = data_length - assoc_data_length;
111 code = krb5_c_crypto_length(ctx->kerberosCtx, ctx->encryptionType,
112 KRB5_CRYPTO_TYPE_HEADER, &k5_headerlen);
116 code = krb5_c_padding_length(ctx->kerberosCtx, ctx->encryptionType,
117 conf_data_length + 16 /* E(Header) */,
122 if (k5_padlen == 0 && (ctx->gssFlags & GSS_C_DCE_STYLE)) {
123 /* Windows rejects AEAD tokens with non-zero EC */
124 code = krb5_c_block_size(ctx->kerberosCtx, ctx->encryptionType, &ec);
130 code = krb5_c_crypto_length(ctx->kerberosCtx, ctx->encryptionType,
131 KRB5_CRYPTO_TYPE_TRAILER, &k5_trailerlen);
135 gss_headerlen = 16 /* Header */ + k5_headerlen;
136 gss_trailerlen = ec + 16 /* E(Header) */ + k5_trailerlen;
138 if (trailer == NULL) {
139 rrc = gss_trailerlen;
140 /* Workaround for Windows bug where it rotates by EC + RRC */
141 if (ctx->gssFlags & GSS_C_DCE_STYLE)
143 gss_headerlen += gss_trailerlen;
146 if (header->type & GSS_IOV_BUFFER_FLAG_ALLOCATE) {
147 code = gssEapAllocIov(header, (size_t) gss_headerlen);
148 } else if (header->buffer.length < gss_headerlen)
149 code = KRB5_BAD_MSIZE;
152 outbuf = (unsigned char *)header->buffer.value;
153 header->buffer.length = (size_t) gss_headerlen;
155 if (trailer != NULL) {
156 if (trailer->type & GSS_IOV_BUFFER_FLAG_ALLOCATE)
157 code = gssEapAllocIov(trailer, (size_t) gss_trailerlen);
158 else if (trailer->buffer.length < gss_trailerlen)
159 code = KRB5_BAD_MSIZE;
162 trailer->buffer.length = (size_t) gss_trailerlen;
166 store_16_be((uint16_t)toktype, outbuf);
168 outbuf[2] = (acceptor_flag
169 | (conf_req_flag ? TOK_FLAG_WRAP_CONFIDENTIAL : 0)
170 | (0 ? TOK_FLAG_ACCEPTOR_SUBKEY : 0));
174 store_16_be(ec, outbuf + 4);
176 store_16_be(0, outbuf + 6);
177 store_64_be(ctx->sendSeq, outbuf + 8);
179 /* EC | copy of header to be encrypted, located in (possibly rotated) trailer */
181 tbuf = (unsigned char *)header->buffer.value + 16; /* Header */
183 tbuf = (unsigned char *)trailer->buffer.value;
185 memset(tbuf, 0xFF, ec);
186 memcpy(tbuf + ec, header->buffer.value, 16);
188 code = gssEapEncrypt(ctx->kerberosCtx,
189 ((ctx->gssFlags & GSS_C_DCE_STYLE) != 0),
190 ec, rrc, ctx->encryptionKey,
191 key_usage, 0, iov, iov_count);
196 store_16_be(rrc, outbuf + 6);
199 } else if (toktype == TOK_TYPE_WRAP && !conf_req_flag) {
204 code = krb5_c_crypto_length(ctx->kerberosCtx, ctx->encryptionType,
205 KRB5_CRYPTO_TYPE_CHECKSUM,
210 assert(gss_trailerlen <= 0xFFFF);
212 if (trailer == NULL) {
213 rrc = gss_trailerlen;
214 gss_headerlen += gss_trailerlen;
217 if (header->type & GSS_IOV_BUFFER_FLAG_ALLOCATE)
218 code = gssEapAllocIov(header, (size_t) gss_headerlen);
219 else if (header->buffer.length < gss_headerlen)
220 code = KRB5_BAD_MSIZE;
223 outbuf = (unsigned char *)header->buffer.value;
224 header->buffer.length = (size_t) gss_headerlen;
226 if (trailer != NULL) {
227 if (trailer->type & GSS_IOV_BUFFER_FLAG_ALLOCATE)
228 code = gssEapAllocIov(trailer, (size_t) gss_trailerlen);
229 else if (trailer->buffer.length < gss_trailerlen)
230 code = KRB5_BAD_MSIZE;
233 trailer->buffer.length = (size_t) gss_trailerlen;
237 store_16_be((uint16_t)toktype, outbuf);
239 outbuf[2] = (acceptor_flag
240 | (0 ? TOK_FLAG_ACCEPTOR_SUBKEY : 0));
243 if (toktype == TOK_TYPE_WRAP) {
244 /* Use 0 for checksum calculation, substitute
245 * checksum length later.
248 store_16_be(0, outbuf + 4);
250 store_16_be(0, outbuf + 6);
252 /* MIC and DEL store 0xFF in EC and RRC */
253 store_16_be(0xFFFF, outbuf + 4);
254 store_16_be(0xFFFF, outbuf + 6);
256 store_64_be(ctx->sendSeq, outbuf + 8);
258 code = gssEapSign(ctx->kerberosCtx, ctx->checksumType,
259 rrc, ctx->encryptionKey, key_usage,
266 if (toktype == TOK_TYPE_WRAP) {
267 /* Fix up EC field */
268 store_16_be(gss_trailerlen, outbuf + 4);
269 /* Fix up RRC field */
270 store_16_be(rrc, outbuf + 6);
272 } else if (toktype == TOK_TYPE_MIC) {
274 goto wrap_with_checksum;
275 } else if (toktype == TOK_TYPE_DELETE) {
276 goto wrap_with_checksum;
285 gssEapReleaseIov(iov, iov_count);
290 return GSS_S_FAILURE;
292 return GSS_S_COMPLETE;
296 gss_wrap_iov(OM_uint32 *minor,
301 gss_iov_buffer_desc *iov,
304 return gssEapWrapOrGetMIC(minor, ctx, conf_req_flag, conf_state,
305 iov, iov_count, TOK_TYPE_WRAP);