Bug Summary

File:src/usr.bin/ssh/ssh-keyscan/../ssh-ed25519.c
Warning:line 56, column 7
Although the value stored to 'ret' is used in the enclosing expression, the value is never actually read from 'ret'

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 ssh-ed25519.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/usr.bin/ssh/ssh-keyscan/obj -resource-dir /usr/local/lib/clang/13.0.0 -I /usr/src/usr.bin/ssh/ssh-keyscan/.. -D WITH_OPENSSL -D WITH_ZLIB -D ENABLE_PKCS11 -D HAVE_DLOPEN -internal-isystem /usr/local/lib/clang/13.0.0/include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -fdebug-compilation-dir=/usr/src/usr.bin/ssh/ssh-keyscan/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/usr.bin/ssh/ssh-keyscan/../ssh-ed25519.c
1/* $OpenBSD: ssh-ed25519.c,v 1.9 2020/10/18 11:32:02 djm Exp $ */
2/*
3 * Copyright (c) 2013 Markus Friedl <markus@openbsd.org>
4 *
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 */
17#define SSHKEY_INTERNAL
18#include <sys/types.h>
19#include <limits.h>
20
21#include "crypto_api.h"
22
23#include <string.h>
24#include <stdarg.h>
25
26#include "log.h"
27#include "sshbuf.h"
28#include "sshkey.h"
29#include "ssherr.h"
30#include "ssh.h"
31
32int
33ssh_ed25519_sign(const struct sshkey *key, u_char **sigp, size_t *lenp,
34 const u_char *data, size_t datalen, u_int compat)
35{
36 u_char *sig = NULL((void *)0);
37 size_t slen = 0, len;
38 unsigned long long smlen;
39 int r, ret;
40 struct sshbuf *b = NULL((void *)0);
41
42 if (lenp != NULL((void *)0))
43 *lenp = 0;
44 if (sigp != NULL((void *)0))
45 *sigp = NULL((void *)0);
46
47 if (key == NULL((void *)0) ||
48 sshkey_type_plain(key->type) != KEY_ED25519 ||
49 key->ed25519_sk == NULL((void *)0) ||
50 datalen >= INT_MAX2147483647 - crypto_sign_ed25519_BYTES64U)
51 return SSH_ERR_INVALID_ARGUMENT-10;
52 smlen = slen = datalen + crypto_sign_ed25519_BYTES64U;
53 if ((sig = malloc(slen)) == NULL((void *)0))
54 return SSH_ERR_ALLOC_FAIL-2;
55
56 if ((ret = crypto_sign_ed25519(sig, &smlen, data, datalen,
Although the value stored to 'ret' is used in the enclosing expression, the value is never actually read from 'ret'
57 key->ed25519_sk)) != 0 || smlen <= datalen) {
58 r = SSH_ERR_INVALID_ARGUMENT-10; /* XXX better error? */
59 goto out;
60 }
61 /* encode signature */
62 if ((b = sshbuf_new()) == NULL((void *)0)) {
63 r = SSH_ERR_ALLOC_FAIL-2;
64 goto out;
65 }
66 if ((r = sshbuf_put_cstring(b, "ssh-ed25519")) != 0 ||
67 (r = sshbuf_put_string(b, sig, smlen - datalen)) != 0)
68 goto out;
69 len = sshbuf_len(b);
70 if (sigp != NULL((void *)0)) {
71 if ((*sigp = malloc(len)) == NULL((void *)0)) {
72 r = SSH_ERR_ALLOC_FAIL-2;
73 goto out;
74 }
75 memcpy(*sigp, sshbuf_ptr(b), len);
76 }
77 if (lenp != NULL((void *)0))
78 *lenp = len;
79 /* success */
80 r = 0;
81 out:
82 sshbuf_free(b);
83 if (sig != NULL((void *)0))
84 freezero(sig, slen);
85
86 return r;
87}
88
89int
90ssh_ed25519_verify(const struct sshkey *key,
91 const u_char *signature, size_t signaturelen,
92 const u_char *data, size_t datalen, u_int compat)
93{
94 struct sshbuf *b = NULL((void *)0);
95 char *ktype = NULL((void *)0);
96 const u_char *sigblob;
97 u_char *sm = NULL((void *)0), *m = NULL((void *)0);
98 size_t len;
99 unsigned long long smlen = 0, mlen = 0;
100 int r, ret;
101
102 if (key == NULL((void *)0) ||
103 sshkey_type_plain(key->type) != KEY_ED25519 ||
104 key->ed25519_pk == NULL((void *)0) ||
105 datalen >= INT_MAX2147483647 - crypto_sign_ed25519_BYTES64U ||
106 signature == NULL((void *)0) || signaturelen == 0)
107 return SSH_ERR_INVALID_ARGUMENT-10;
108
109 if ((b = sshbuf_from(signature, signaturelen)) == NULL((void *)0))
110 return SSH_ERR_ALLOC_FAIL-2;
111 if ((r = sshbuf_get_cstring(b, &ktype, NULL((void *)0))) != 0 ||
112 (r = sshbuf_get_string_direct(b, &sigblob, &len)) != 0)
113 goto out;
114 if (strcmp("ssh-ed25519", ktype) != 0) {
115 r = SSH_ERR_KEY_TYPE_MISMATCH-13;
116 goto out;
117 }
118 if (sshbuf_len(b) != 0) {
119 r = SSH_ERR_UNEXPECTED_TRAILING_DATA-23;
120 goto out;
121 }
122 if (len > crypto_sign_ed25519_BYTES64U) {
123 r = SSH_ERR_INVALID_FORMAT-4;
124 goto out;
125 }
126 if (datalen >= SIZE_MAX0xffffffffffffffffUL - len) {
127 r = SSH_ERR_INVALID_ARGUMENT-10;
128 goto out;
129 }
130 smlen = len + datalen;
131 mlen = smlen;
132 if ((sm = malloc(smlen)) == NULL((void *)0) || (m = malloc(mlen)) == NULL((void *)0)) {
133 r = SSH_ERR_ALLOC_FAIL-2;
134 goto out;
135 }
136 memcpy(sm, sigblob, len);
137 memcpy(sm+len, data, datalen);
138 if ((ret = crypto_sign_ed25519_open(m, &mlen, sm, smlen,
139 key->ed25519_pk)) != 0) {
140 debug2_f("crypto_sign_ed25519_open failed: %d", ret)sshlog("/usr/src/usr.bin/ssh/ssh-keyscan/../ssh-ed25519.c", __func__
, 140, 1, SYSLOG_LEVEL_DEBUG2, ((void *)0), "crypto_sign_ed25519_open failed: %d"
, ret);
141 }
142 if (ret != 0 || mlen != datalen) {
143 r = SSH_ERR_SIGNATURE_INVALID-21;
144 goto out;
145 }
146 /* XXX compare 'm' and 'data' ? */
147 /* success */
148 r = 0;
149 out:
150 if (sm != NULL((void *)0))
151 freezero(sm, smlen);
152 if (m != NULL((void *)0))
153 freezero(m, smlen); /* NB mlen may be invalid if r != 0 */
154 sshbuf_free(b);
155 free(ktype);
156 return r;
157}