Bug Summary

File:src/lib/libcrypto/des/cfb64enc.c
Warning:line 120, column 2
Value stored to 'v0' is never read

Annotated Source Code

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clang -cc1 -cc1 -triple amd64-unknown-openbsd7.4 -analyze -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name cfb64enc.c -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -mrelocation-model pic -pic-level 1 -pic-is-pie -mframe-pointer=all -relaxed-aliasing -ffp-contract=on -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -target-feature +retpoline-indirect-calls -target-feature +retpoline-indirect-branches -tune-cpu generic -debugger-tuning=gdb -fcoverage-compilation-dir=/usr/src/lib/libcrypto/obj -resource-dir /usr/local/llvm16/lib/clang/16 -D LIBRESSL_INTERNAL -D HAVE_FUNOPEN -I /usr/src/lib/libcrypto -I /usr/src/lib/libcrypto/arch/amd64 -I /usr/src/lib/libcrypto/asn1 -I /usr/src/lib/libcrypto/bio -I /usr/src/lib/libcrypto/bn -I /usr/src/lib/libcrypto/bn/arch/amd64 -I /usr/src/lib/libcrypto/bytestring -I /usr/src/lib/libcrypto/curve25519 -I /usr/src/lib/libcrypto/dh -I /usr/src/lib/libcrypto/dsa -I /usr/src/lib/libcrypto/ec -I /usr/src/lib/libcrypto/ecdsa -I /usr/src/lib/libcrypto/evp -I /usr/src/lib/libcrypto/hidden -I /usr/src/lib/libcrypto/hmac -I /usr/src/lib/libcrypto/kdf -I /usr/src/lib/libcrypto/modes -I /usr/src/lib/libcrypto/ocsp -I /usr/src/lib/libcrypto/pkcs12 -I /usr/src/lib/libcrypto/rsa -I /usr/src/lib/libcrypto/sha -I /usr/src/lib/libcrypto/ts -I /usr/src/lib/libcrypto/x509 -I /usr/src/lib/libcrypto/obj -D AES_ASM -D BSAES_ASM -D VPAES_ASM -D OPENSSL_IA32_SSE2 -D RSA_ASM -D OPENSSL_BN_ASM_MONT -D OPENSSL_BN_ASM_MONT5 -D MD5_ASM -D GHASH_ASM -D RC4_MD5_ASM -D SHA1_ASM -D SHA256_ASM -D SHA512_ASM -D WHIRLPOOL_ASM -D OPENSSL_CPUID_OBJ -internal-isystem /usr/local/llvm16/lib/clang/16/include -internal-externc-isystem /usr/include -O2 -fdebug-compilation-dir=/usr/src/lib/libcrypto/obj -ferror-limit 19 -fwrapv -D_RET_PROTECTOR -ret-protector -fcf-protection=branch -fno-jump-tables -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -fno-builtin-malloc -fno-builtin-calloc -fno-builtin-realloc -fno-builtin-valloc -fno-builtin-free -fno-builtin-strdup -fno-builtin-strndup -analyzer-output=html -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /home/ben/Projects/scan/2024-01-11-140451-98009-1 -x c /usr/src/lib/libcrypto/des/cfb64enc.c
1/* $OpenBSD: cfb64enc.c,v 1.8 2023/07/08 07:11:07 beck Exp $ */
2/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3 * All rights reserved.
4 *
5 * This package is an SSL implementation written
6 * by Eric Young (eay@cryptsoft.com).
7 * The implementation was written so as to conform with Netscapes SSL.
8 *
9 * This library is free for commercial and non-commercial use as long as
10 * the following conditions are aheared to. The following conditions
11 * apply to all code found in this distribution, be it the RC4, RSA,
12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
13 * included with this distribution is covered by the same copyright terms
14 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15 *
16 * Copyright remains Eric Young's, and as such any Copyright notices in
17 * the code are not to be removed.
18 * If this package is used in a product, Eric Young should be given attribution
19 * as the author of the parts of the library used.
20 * This can be in the form of a textual message at program startup or
21 * in documentation (online or textual) provided with the package.
22 *
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
25 * are met:
26 * 1. Redistributions of source code must retain the copyright
27 * notice, this list of conditions and the following disclaimer.
28 * 2. Redistributions in binary form must reproduce the above copyright
29 * notice, this list of conditions and the following disclaimer in the
30 * documentation and/or other materials provided with the distribution.
31 * 3. All advertising materials mentioning features or use of this software
32 * must display the following acknowledgement:
33 * "This product includes cryptographic software written by
34 * Eric Young (eay@cryptsoft.com)"
35 * The word 'cryptographic' can be left out if the rouines from the library
36 * being used are not cryptographic related :-).
37 * 4. If you include any Windows specific code (or a derivative thereof) from
38 * the apps directory (application code) you must include an acknowledgement:
39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40 *
41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51 * SUCH DAMAGE.
52 *
53 * The licence and distribution terms for any publically available version or
54 * derivative of this code cannot be changed. i.e. this code cannot simply be
55 * copied and put under another distribution licence
56 * [including the GNU Public Licence.]
57 */
58
59#include "des_local.h"
60
61/* The input and output encrypted as though 64bit cfb mode is being
62 * used. The extra state information to record how much of the
63 * 64bit block we have used is contained in *num;
64 */
65
66void
67DES_cfb64_encrypt(const unsigned char *in, unsigned char *out,
68 long length, DES_key_schedule *schedule,
69 DES_cblock *ivec, int *num, int enc)
70{
71 DES_LONGunsigned int v0, v1;
72 long l = length;
73 int n = *num;
74 DES_LONGunsigned int ti[2];
75 unsigned char *iv, c, cc;
76
77 iv = &(*ivec)[0];
78 if (enc) {
79 while (l--) {
80 if (n == 0) {
81 c2l(iv, v0)(v0 =((unsigned int)(*((iv)++))) , v0|=((unsigned int)(*((iv)
++)))<< 8L, v0|=((unsigned int)(*((iv)++)))<<16L,
v0|=((unsigned int)(*((iv)++)))<<24L)
;
82 ti[0] = v0;
83 c2l(iv, v1)(v1 =((unsigned int)(*((iv)++))) , v1|=((unsigned int)(*((iv)
++)))<< 8L, v1|=((unsigned int)(*((iv)++)))<<16L,
v1|=((unsigned int)(*((iv)++)))<<24L)
;
84 ti[1] = v1;
85 DES_encrypt1(ti, schedule, DES_ENCRYPT1);
86 iv = &(*ivec)[0];
87 v0 = ti[0];
88 l2c(v0, iv)(*((iv)++)=(unsigned char)(((v0) )&0xff), *((iv)++)=(unsigned
char)(((v0)>> 8L)&0xff), *((iv)++)=(unsigned char)
(((v0)>>16L)&0xff), *((iv)++)=(unsigned char)(((v0)
>>24L)&0xff))
;
89 v0 = ti[1];
90 l2c(v0, iv)(*((iv)++)=(unsigned char)(((v0) )&0xff), *((iv)++)=(unsigned
char)(((v0)>> 8L)&0xff), *((iv)++)=(unsigned char)
(((v0)>>16L)&0xff), *((iv)++)=(unsigned char)(((v0)
>>24L)&0xff))
;
91 iv = &(*ivec)[0];
92 }
93 c = *(in++) ^ iv[n];
94 *(out++) = c;
95 iv[n] = c;
96 n = (n + 1) & 0x07;
97 }
98 } else {
99 while (l--) {
100 if (n == 0) {
101 c2l(iv, v0)(v0 =((unsigned int)(*((iv)++))) , v0|=((unsigned int)(*((iv)
++)))<< 8L, v0|=((unsigned int)(*((iv)++)))<<16L,
v0|=((unsigned int)(*((iv)++)))<<24L)
;
102 ti[0] = v0;
103 c2l(iv, v1)(v1 =((unsigned int)(*((iv)++))) , v1|=((unsigned int)(*((iv)
++)))<< 8L, v1|=((unsigned int)(*((iv)++)))<<16L,
v1|=((unsigned int)(*((iv)++)))<<24L)
;
104 ti[1] = v1;
105 DES_encrypt1(ti, schedule, DES_ENCRYPT1);
106 iv = &(*ivec)[0];
107 v0 = ti[0];
108 l2c(v0, iv)(*((iv)++)=(unsigned char)(((v0) )&0xff), *((iv)++)=(unsigned
char)(((v0)>> 8L)&0xff), *((iv)++)=(unsigned char)
(((v0)>>16L)&0xff), *((iv)++)=(unsigned char)(((v0)
>>24L)&0xff))
;
109 v0 = ti[1];
110 l2c(v0, iv)(*((iv)++)=(unsigned char)(((v0) )&0xff), *((iv)++)=(unsigned
char)(((v0)>> 8L)&0xff), *((iv)++)=(unsigned char)
(((v0)>>16L)&0xff), *((iv)++)=(unsigned char)(((v0)
>>24L)&0xff))
;
111 iv = &(*ivec)[0];
112 }
113 cc = *(in++);
114 c = iv[n];
115 iv[n] = cc;
116 *(out++) = c ^ cc;
117 n = (n + 1) & 0x07;
118 }
119 }
120 v0 = v1 = ti[0] = ti[1] = c = cc = 0;
Value stored to 'v0' is never read
121 *num = n;
122}