Bug Summary

File:src/lib/libcrypto/cast/c_cfb64.c
Warning:line 119, column 2
Value stored to 'v0' is never read

Annotated Source Code

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clang -cc1 -cc1 -triple amd64-unknown-openbsd7.0 -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name c_cfb64.c -analyzer-store=region -analyzer-opt-analyze-nested-blocks -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 -fno-rounding-math -mconstructor-aliases -munwind-tables -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/lib/clang/13.0.0 -D LIBRESSL_INTERNAL -D LIBRESSL_CRYPTO_INTERNAL -D DSO_DLFCN -D HAVE_DLFCN_H -D HAVE_FUNOPEN -D OPENSSL_NO_HW_PADLOCK -I /usr/src/lib/libcrypto -I /usr/src/lib/libcrypto/asn1 -I /usr/src/lib/libcrypto/bio -I /usr/src/lib/libcrypto/bn -I /usr/src/lib/libcrypto/bytestring -I /usr/src/lib/libcrypto/dh -I /usr/src/lib/libcrypto/dsa -I /usr/src/lib/libcrypto/ec -I /usr/src/lib/libcrypto/ecdh -I /usr/src/lib/libcrypto/ecdsa -I /usr/src/lib/libcrypto/evp -I /usr/src/lib/libcrypto/hmac -I /usr/src/lib/libcrypto/modes -I /usr/src/lib/libcrypto/ocsp -I /usr/src/lib/libcrypto/rsa -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 OPENSSL_BN_ASM_GF2m -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/lib/clang/13.0.0/include -internal-externc-isystem /usr/include -O2 -fdebug-compilation-dir=/usr/src/lib/libcrypto/obj -ferror-limit 19 -fwrapv -D_RET_PROTECTOR -ret-protector -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/vmm/scan-build/2022-01-12-194120-40624-1 -x c /usr/src/lib/libcrypto/cast/c_cfb64.c
1/* $OpenBSD: c_cfb64.c,v 1.5 2014/10/28 07:35:58 jsg 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 <openssl/cast.h>
60#include "cast_lcl.h"
61
62/* The input and output encrypted as though 64bit cfb mode is being
63 * used. The extra state information to record how much of the
64 * 64bit block we have used is contained in *num;
65 */
66
67void CAST_cfb64_encrypt(const unsigned char *in, unsigned char *out,
68 long length, const CAST_KEY *schedule, unsigned char *ivec,
69 int *num, int enc)
70 {
71 CAST_LONGunsigned int v0,v1,t;
72 int n= *num;
73 long l=length;
74 CAST_LONGunsigned int ti[2];
75 unsigned char *iv,c,cc;
76
77 iv=ivec;
78 if (enc)
79 {
80 while (l--)
81 {
82 if (n == 0)
83 {
84 n2l(iv,v0)(v0 =((unsigned long)(*((iv)++)))<<24L, v0|=((unsigned long
)(*((iv)++)))<<16L, v0|=((unsigned long)(*((iv)++)))<<
8L, v0|=((unsigned long)(*((iv)++))))
; ti[0]=v0;
85 n2l(iv,v1)(v1 =((unsigned long)(*((iv)++)))<<24L, v1|=((unsigned long
)(*((iv)++)))<<16L, v1|=((unsigned long)(*((iv)++)))<<
8L, v1|=((unsigned long)(*((iv)++))))
; ti[1]=v1;
86 CAST_encrypt((CAST_LONGunsigned int *)ti,schedule);
87 iv=ivec;
88 t=ti[0]; l2n(t,iv)(*((iv)++)=(unsigned char)(((t)>>24L)&0xff), *((iv)
++)=(unsigned char)(((t)>>16L)&0xff), *((iv)++)=(unsigned
char)(((t)>> 8L)&0xff), *((iv)++)=(unsigned char)(
((t) )&0xff))
;
89 t=ti[1]; l2n(t,iv)(*((iv)++)=(unsigned char)(((t)>>24L)&0xff), *((iv)
++)=(unsigned char)(((t)>>16L)&0xff), *((iv)++)=(unsigned
char)(((t)>> 8L)&0xff), *((iv)++)=(unsigned char)(
((t) )&0xff))
;
90 iv=ivec;
91 }
92 c= *(in++)^iv[n];
93 *(out++)=c;
94 iv[n]=c;
95 n=(n+1)&0x07;
96 }
97 }
98 else
99 {
100 while (l--)
101 {
102 if (n == 0)
103 {
104 n2l(iv,v0)(v0 =((unsigned long)(*((iv)++)))<<24L, v0|=((unsigned long
)(*((iv)++)))<<16L, v0|=((unsigned long)(*((iv)++)))<<
8L, v0|=((unsigned long)(*((iv)++))))
; ti[0]=v0;
105 n2l(iv,v1)(v1 =((unsigned long)(*((iv)++)))<<24L, v1|=((unsigned long
)(*((iv)++)))<<16L, v1|=((unsigned long)(*((iv)++)))<<
8L, v1|=((unsigned long)(*((iv)++))))
; ti[1]=v1;
106 CAST_encrypt((CAST_LONGunsigned int *)ti,schedule);
107 iv=ivec;
108 t=ti[0]; l2n(t,iv)(*((iv)++)=(unsigned char)(((t)>>24L)&0xff), *((iv)
++)=(unsigned char)(((t)>>16L)&0xff), *((iv)++)=(unsigned
char)(((t)>> 8L)&0xff), *((iv)++)=(unsigned char)(
((t) )&0xff))
;
109 t=ti[1]; l2n(t,iv)(*((iv)++)=(unsigned char)(((t)>>24L)&0xff), *((iv)
++)=(unsigned char)(((t)>>16L)&0xff), *((iv)++)=(unsigned
char)(((t)>> 8L)&0xff), *((iv)++)=(unsigned char)(
((t) )&0xff))
;
110 iv=ivec;
111 }
112 cc= *(in++);
113 c=iv[n];
114 iv[n]=cc;
115 *(out++)=c^cc;
116 n=(n+1)&0x07;
117 }
118 }
119 v0=v1=ti[0]=ti[1]=t=c=cc=0;
Value stored to 'v0' is never read
120 *num=n;
121 }