shaba/systemd
1
0
Fork 0
mirror of https://github.com/systemd/systemd.git synced 2025-01-09 01:18:19 +03:00
Code

string-util: introduce explicit_zero_safe()

Browse Source 
The only real difference is that this wrapper can deal with NULL
pointer arguments, but only if the length is also zero.

CID 1396277
This commit is contained in:
Lennart Poettering 2018-10-24 21:00:15 +02:00
parent 7388cea30d
commit 87f5446311
5 changed files with 25 additions and 15 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
src/basic/string-util.c
View File

@ -1059,8 +1059,11 @@ typedef void *(*memset_t)(void *,int,size_t);
static volatile memset_t memset_func = memset;
void explicit_bzero(void *p, size_t l) {
memset_func(p, '\0', l);
void* explicit_bzero_safe(void *p, size_t l) {
if (l > 0)
memset_func(p, '\0', l);
return p;
}
#endif
@ -1070,7 +1073,7 @@ char* string_erase(char *x) {
/* A delicious drop of snake-oil! To be called on memory where
* we stored passphrases or so, after we used them. */
explicit_bzero(x, strlen(x));
explicit_bzero_safe(x, strlen(x));
return x;
}

11
src/basic/string-util.h
View File

@ -198,8 +198,15 @@ static inline void *memmem_safe(const void *haystack, size_t haystacklen, const
return memmem(haystack, haystacklen, needle, needlelen);
}
#if !HAVE_EXPLICIT_BZERO
void explicit_bzero(void *p, size_t l);
#if HAVE_EXPLICIT_BZERO
static inline void* explicit_bzero_safe(void *p, size_t l) {
if (l > 0)
explicit_bzero(p, l);
return p;
}
#else
void explicit_bzero_safe(void *p, size_t l);
#endif
char *string_erase(char *x);

2
src/reply-password/reply-password.c
View File

@ -95,7 +95,7 @@ int main(int argc, char *argv[]) {
r = send_on_socket(fd, argv[2], packet, length);
finish:
explicit_bzero(packet, length);
explicit_bzero_safe(packet, length);
return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
}

14
src/shared/ask-password-api.c
View File

@ -79,7 +79,7 @@ static int retrieve_key(key_serial_t serial, char ***ret) {
if (n < m)
break;
explicit_bzero(p, n);
explicit_bzero_safe(p, n);
free(p);
m *= 2;
}
@ -88,7 +88,7 @@ static int retrieve_key(key_serial_t serial, char ***ret) {
if (!l)
return -ENOMEM;
explicit_bzero(p, n);
explicit_bzero_safe(p, n);
*ret = l;
return 0;
@ -124,7 +124,7 @@ static int add_to_keyring(const char *keyname, AskPasswordFlags flags, char **pa
return r;
serial = add_key("user", keyname, p, n, KEY_SPEC_USER_KEYRING);
explicit_bzero(p, n);
explicit_bzero_safe(p, n);
if (serial == -1)
return -errno;
@ -349,7 +349,7 @@ int ask_password_tty(
if (!(flags & ASK_PASSWORD_SILENT))
backspace_string(ttyfd, passphrase);
explicit_bzero(passphrase, sizeof(passphrase));
explicit_bzero_safe(passphrase, sizeof(passphrase));
p = codepoint = 0;
} else if (IN_SET(c, '\b', 127)) {
@ -379,7 +379,7 @@ int ask_password_tty(
}
p = codepoint = q == (size_t) -1 ? p - 1 : q;
explicit_bzero(passphrase + p, sizeof(passphrase) - p);
explicit_bzero_safe(passphrase + p, sizeof(passphrase) - p);
} else if (!dirty && !(flags & ASK_PASSWORD_SILENT)) {
@ -430,7 +430,7 @@ int ask_password_tty(
}
x = strndup(passphrase, p);
explicit_bzero(passphrase, sizeof(passphrase));
explicit_bzero_safe(passphrase, sizeof(passphrase));
if (!x) {
r = -ENOMEM;
goto finish;
@ -681,7 +681,7 @@ int ask_password_agent(
l = strv_new("", NULL);
else
l = strv_parse_nulstr(passphrase+1, n-1);
explicit_bzero(passphrase, n);
explicit_bzero_safe(passphrase, n);
if (!l) {
r = -ENOMEM;
goto finish;

4
src/tty-ask-password-agent/tty-ask-password-agent.c
View File

@ -228,7 +228,7 @@ static int ask_password_plymouth(
r = 0;
finish:
explicit_bzero(buffer, sizeof(buffer));
explicit_bzero_safe(buffer, sizeof(buffer));
return r;
}
@ -275,7 +275,7 @@ static int send_passwords(const char *socket_name, char **passwords) {
r = (int) n;
finish:
explicit_bzero(packet, packet_length);
explicit_bzero_safe(packet, packet_length);
return r;
}