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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-04 01:24:41 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-04 01:24:41 +0000 |
commit | a9bcc81f821d7c66f623779fa5147e728eb3c388 (patch) | |
tree | 98676963bcdd537ae5908a067a8eb110b93486a6 /winpr/libwinpr/crypto/rc4.c | |
parent | Initial commit. (diff) | |
download | freerdp3-a9bcc81f821d7c66f623779fa5147e728eb3c388.tar.xz freerdp3-a9bcc81f821d7c66f623779fa5147e728eb3c388.zip |
Adding upstream version 3.3.0+dfsg1.upstream/3.3.0+dfsg1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'winpr/libwinpr/crypto/rc4.c')
-rw-r--r-- | winpr/libwinpr/crypto/rc4.c | 88 |
1 files changed, 88 insertions, 0 deletions
diff --git a/winpr/libwinpr/crypto/rc4.c b/winpr/libwinpr/crypto/rc4.c new file mode 100644 index 0000000..e170785 --- /dev/null +++ b/winpr/libwinpr/crypto/rc4.c @@ -0,0 +1,88 @@ +/** + * WinPR: Windows Portable Runtime + * RC4 implementation for RDP + * + * Copyright 2023 Armin Novak <anovak@thincast.com> + * Copyright 2023 Thincast Technologies GmbH + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +#include <winpr/assert.h> + +#include "rc4.h" + +#define CTX_SIZE 256 + +struct winpr_int_rc4_ctx +{ + size_t i; + size_t j; + BYTE s[CTX_SIZE]; + BYTE t[CTX_SIZE]; +}; + +static void swap(BYTE* p1, BYTE* p2) +{ + BYTE t = *p1; + *p1 = *p2; + *p2 = t; +} + +winpr_int_RC4_CTX* winpr_int_rc4_new(const BYTE* key, size_t keylength) +{ + winpr_int_RC4_CTX* ctx = calloc(1, sizeof(winpr_int_RC4_CTX)); + if (!ctx) + return NULL; + + for (size_t i = 0; i < CTX_SIZE; i++) + { + ctx->s[i] = i; + ctx->t[i] = key[i % keylength]; + } + + size_t j = 0; + for (size_t i = 0; i < CTX_SIZE; i++) + { + j = (j + ctx->s[i] + ctx->t[i]) % CTX_SIZE; + swap(&ctx->s[i], &ctx->s[j]); + } + return ctx; +} + +void winpr_int_rc4_free(winpr_int_RC4_CTX* ctx) +{ + free(ctx); +} + +BOOL winpr_int_rc4_update(winpr_int_RC4_CTX* ctx, size_t length, const BYTE* input, BYTE* output) +{ + WINPR_ASSERT(ctx); + + UINT32 t1 = ctx->i; + UINT32 t2 = ctx->j; + for (size_t i = 0; i < length; i++) + { + t1 = (t1 + 1) % CTX_SIZE; + t2 = (t2 + ctx->s[t1]) % CTX_SIZE; + swap(&ctx->s[t1], &ctx->s[t2]); + + const size_t idx = ((size_t)ctx->s[t1] + ctx->s[t2]) % CTX_SIZE; + const BYTE val = ctx->s[idx]; + const BYTE out = *input++ ^ val; + *output++ = out; + } + + ctx->i = t1; + ctx->j = t2; + return TRUE; +} |