From: Rong Tao <rongtao(a)cestc.cn>
bpf_strcasestr() and bpf_strncasestr() functions perform same like
bpf_strstr() and bpf_strnstr() except ignoring the case of the
characters.
Signed-off-by: Rong Tao <rongtao(a)cestc.cn>
---
kernel/bpf/helpers.c | 96 ++++++++++++++++++++++++++++++++++----------
1 file changed, 75 insertions(+), 21 deletions(-)
diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
index c9fab9a356df..4df902e5f208 100644
--- a/kernel/bpf/helpers.c
+++ b/kernel/bpf/helpers.c
@@ -3675,34 +3675,20 @@ __bpf_kfunc int bpf_strcspn(const char *s__ign, const char *reject__ign)
return -EFAULT;
}
-/**
- * bpf_strnstr - Find the first substring in a length-limited string
- * @s1__ign: The string to be searched
- * @s2__ign: The string to search for
- * @len: the maximum number of characters to search
- *
- * Return:
- * * >=0 - Index of the first character of the first occurrence of @s2__ign
- * within the first @len characters of @s1__ign
- * * %-ENOENT - @s2__ign not found in the first @len characters of @s1__ign
- * * %-EFAULT - Cannot read one of the strings
- * * %-E2BIG - One of the strings is too large
- * * %-ERANGE - One of the strings is outside of kernel address space
- */
-__bpf_kfunc int bpf_strnstr(const char *s1__ign, const char *s2__ign, size_t len)
+int __bpf_strnstr(const char *s1, const char *s2, size_t len, bool ignore_case)
{
char c1, c2;
int i, j;
- if (!copy_from_kernel_nofault_allowed(s1__ign, 1) ||
- !copy_from_kernel_nofault_allowed(s2__ign, 1)) {
+ if (!copy_from_kernel_nofault_allowed(s1, 1) ||
+ !copy_from_kernel_nofault_allowed(s2, 1)) {
return -ERANGE;
}
guard(pagefault)();
for (i = 0; i < XATTR_SIZE_MAX; i++) {
for (j = 0; i + j <= len && j < XATTR_SIZE_MAX; j++) {
- __get_kernel_nofault(&c2, s2__ign + j, char, err_out);
+ __get_kernel_nofault(&c2, s2 + j, char, err_out);
if (c2 == '\0')
return i;
/*
@@ -3712,7 +3698,13 @@ __bpf_kfunc int bpf_strnstr(const char *s1__ign, const char *s2__ign, size_t len
*/
if (i + j == len)
break;
- __get_kernel_nofault(&c1, s1__ign + j, char, err_out);
+ __get_kernel_nofault(&c1, s1 + j, char, err_out);
+
+ if (ignore_case) {
+ c1 = tolower(c1);
+ c2 = tolower(c2);
+ }
+
if (c1 == '\0')
return -ENOENT;
if (c1 != c2)
@@ -3722,7 +3714,7 @@ __bpf_kfunc int bpf_strnstr(const char *s1__ign, const char *s2__ign, size_t len
return -E2BIG;
if (i + j == len)
return -ENOENT;
- s1__ign++;
+ s1++;
}
return -E2BIG;
err_out:
@@ -3744,8 +3736,68 @@ __bpf_kfunc int bpf_strnstr(const char *s1__ign, const char *s2__ign, size_t len
*/
__bpf_kfunc int bpf_strstr(const char *s1__ign, const char *s2__ign)
{
- return bpf_strnstr(s1__ign, s2__ign, XATTR_SIZE_MAX);
+ return __bpf_strnstr(s1__ign, s2__ign, XATTR_SIZE_MAX, false);
+}
+
+/**
+ * bpf_strcasestr - Find the first substring in a string, ignoring the case of
+ * the characters
+ * @s1__ign: The string to be searched
+ * @s2__ign: The string to search for
+ *
+ * Return:
+ * * >=0 - Index of the first character of the first occurrence of @s2__ign
+ * within @s1__ign
+ * * %-ENOENT - @s2__ign is not a substring of @s1__ign
+ * * %-EFAULT - Cannot read one of the strings
+ * * %-E2BIG - One of the strings is too large
+ * * %-ERANGE - One of the strings is outside of kernel address space
+ */
+__bpf_kfunc int bpf_strcasestr(const char *s1__ign, const char *s2__ign)
+{
+ return __bpf_strnstr(s1__ign, s2__ign, XATTR_SIZE_MAX, true);
}
+
+/**
+ * bpf_strnstr - Find the first substring in a length-limited string
+ * @s1__ign: The string to be searched
+ * @s2__ign: The string to search for
+ * @len: the maximum number of characters to search
+ *
+ * Return:
+ * * >=0 - Index of the first character of the first occurrence of @s2__ign
+ * within the first @len characters of @s1__ign
+ * * %-ENOENT - @s2__ign not found in the first @len characters of @s1__ign
+ * * %-EFAULT - Cannot read one of the strings
+ * * %-E2BIG - One of the strings is too large
+ * * %-ERANGE - One of the strings is outside of kernel address space
+ */
+__bpf_kfunc int bpf_strnstr(const char *s1__ign, const char *s2__ign, size_t len)
+{
+ return __bpf_strnstr(s1__ign, s2__ign, len, false);
+}
+
+/**
+ * bpf_strnstr - Find the first substring in a length-limited string, ignoring
+ * the case of the characters
+ * @s1__ign: The string to be searched
+ * @s2__ign: The string to search for
+ * @len: the maximum number of characters to search
+ *
+ * Return:
+ * * >=0 - Index of the first character of the first occurrence of @s2__ign
+ * within the first @len characters of @s1__ign
+ * * %-ENOENT - @s2__ign not found in the first @len characters of @s1__ign
+ * * %-EFAULT - Cannot read one of the strings
+ * * %-E2BIG - One of the strings is too large
+ * * %-ERANGE - One of the strings is outside of kernel address space
+ */
+__bpf_kfunc int bpf_strncasestr(const char *s1__ign, const char *s2__ign,
+ size_t len)
+{
+ return __bpf_strnstr(s1__ign, s2__ign, len, true);
+}
+
#ifdef CONFIG_KEYS
/**
* bpf_lookup_user_key - lookup a key by its serial
@@ -4367,7 +4419,9 @@ BTF_ID_FLAGS(func, bpf_strnlen);
BTF_ID_FLAGS(func, bpf_strspn);
BTF_ID_FLAGS(func, bpf_strcspn);
BTF_ID_FLAGS(func, bpf_strstr);
+BTF_ID_FLAGS(func, bpf_strcasestr);
BTF_ID_FLAGS(func, bpf_strnstr);
+BTF_ID_FLAGS(func, bpf_strncasestr);
#if defined(CONFIG_BPF_LSM) && defined(CONFIG_CGROUPS)
BTF_ID_FLAGS(func, bpf_cgroup_read_xattr, KF_RCU)
#endif
--
2.51.0
From: Rong Tao <rongtao(a)cestc.cn>
Add kfuncs bpf_strcasestr and bpf_strncasestr, which are extensions of
bpf_strstr and bpf_strnstr, suitable for more scenarios.
Rong Tao (2):
bpf: add bpf_strcasestr,bpf_strncasestr kfuncs
selftests/bpf: Test bpf_strcasestr,bpf_strncasestr kfuncs
kernel/bpf/helpers.c | 97 +++++++++++++++----
.../selftests/bpf/prog_tests/string_kfuncs.c | 2 +
.../bpf/progs/string_kfuncs_failure1.c | 12 +++
.../bpf/progs/string_kfuncs_failure2.c | 2 +
.../bpf/progs/string_kfuncs_success.c | 10 ++
5 files changed, 102 insertions(+), 21 deletions(-)
---
v3: keep __bpf_strnstr() static and compress some tests.
v2: remove extra __bpf_kfunc and fix comment of bpf_strncasestr().
https://lore.kernel.org/all/tencent_6D228941AB904DD6E1E58C8ACDEBEC280C06@qq…
v1: https://lore.kernel.org/all/tencent_8AF4D15B4475031E2185ACDE4B1495995707@qq…
--
2.51.0
Fix functions that return undefined values. These issues were caught by
running clang using LLVM=1 option.
Clang warnings are as follows:
ovpn-cli.c:1587:6: warning: variable 'ret' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
1587 | if (!sock) {
| ^~~~~
ovpn-cli.c:1635:9: note: uninitialized use occurs here
1635 | return ret;
| ^~~
ovpn-cli.c:1587:2: note: remove the 'if' if its condition is always false
1587 | if (!sock) {
| ^~~~~~~~~~~~
1588 | fprintf(stderr, "cannot allocate netlink socket\n");
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1589 | goto err_free;
| ~~~~~~~~~~~~~~
1590 | }
| ~
ovpn-cli.c:1584:15: note: initialize the variable 'ret' to silence this warning
1584 | int mcid, ret;
| ^
| = 0
ovpn-cli.c:2107:7: warning: variable 'ret' is used uninitialized whenever switch case is taken [-Wsometimes-uninitialized]
2107 | case CMD_INVALID:
| ^~~~~~~~~~~
ovpn-cli.c:2111:9: note: uninitialized use occurs here
2111 | return ret;
| ^~~
ovpn-cli.c:1939:12: note: initialize the variable 'ret' to silence this warning
1939 | int n, ret;
| ^
|
Fixes: 959bc330a439 ("testing/selftests: add test tool and scripts for ovpn module")
Signed-off-by: Sidharth Seela <sidharthseela(a)gmail.com>
---
v6:
- Remove stray line near Fixes tag.
- Include ovpn prefix in commit message.
v5:
- Assign -ENOMEM to ret inside if block.
- Assign -EINVAL to ret inside case block.
v4:
- Move changelog below sign-off.
- Remove double-hyphens in commit description.
v3:
- Use prefix net.
- Remove so_txtime fix as default case calls error().
- Changelog before sign-off.
- Three dashes after sign-off
v2:
- Use subsystem name "net".
- Add fixes tags.
- Remove txtimestamp fix as default case calls error.
- Assign constant error string instead of NULL.
diff --git a/tools/testing/selftests/net/ovpn/ovpn-cli.c b/tools/testing/selftests/net/ovpn/ovpn-cli.c
index 9201f2905f2c..8d0f2f61923c 100644
--- a/tools/testing/selftests/net/ovpn/ovpn-cli.c
+++ b/tools/testing/selftests/net/ovpn/ovpn-cli.c
@@ -1586,6 +1586,7 @@ static int ovpn_listen_mcast(void)
sock = nl_socket_alloc();
if (!sock) {
fprintf(stderr, "cannot allocate netlink socket\n");
+ ret = -ENOMEM;
goto err_free;
}
@@ -2105,6 +2106,7 @@ static int ovpn_run_cmd(struct ovpn_ctx *ovpn)
ret = ovpn_listen_mcast();
break;
case CMD_INVALID:
+ ret = -EINVAL;
break;
}
--
2.47.3