Neels Hofmeyr has submitted this change and it was merged. (
https://gerrit.osmocom.org/13574 )
Change subject: add identifier sanitation for setting FSM instance ids
......................................................................
add identifier sanitation for setting FSM instance ids
We often compose FSM instance IDs from context information, for example placing
an MSISDN string or IP:port information in the FSM instance id, using
osmo_fsm_inst_update_id_f(). This fails if any characters are contained that
don't pass osmo_identifier_valid(). Hence it is the task of the caller to make
sure only characters allowed in an FSM id are applied.
Provide API to trivially allow this by replacing illegal chars:
- osmo_identifier_sanitize_buf(), with access to the same set of illegal
characters defined in utils.c,
- osmo_fsm_inst_update_id_f_sanitize() implicitly replaces non-identifier
chars.
This makes it easy to add strings like '192.168.0.1:2342' or '+4987654321' to
an FSM instance id, without adding string mangling to each place that sets an
id; e.g. replacing with '-' to yield '192-168-0-1:2342' or '-4987654321'.
Change-Id: Ia40a6f3b2243c95fe428a080b938e11d8ab771a7
---
M include/osmocom/core/fsm.h
M include/osmocom/core/utils.h
M src/fsm.c
M src/utils.c
4 files changed, 53 insertions(+), 2 deletions(-)
Approvals:
Jenkins Builder: Verified
Harald Welte: Looks good to me, approved
diff --git a/include/osmocom/core/fsm.h b/include/osmocom/core/fsm.h
index c9e1e0c..41d01a5 100644
--- a/include/osmocom/core/fsm.h
+++ b/include/osmocom/core/fsm.h
@@ -220,6 +220,7 @@
int osmo_fsm_inst_update_id(struct osmo_fsm_inst *fi, const char *id);
int osmo_fsm_inst_update_id_f(struct osmo_fsm_inst *fi, const char *fmt, ...);
+int osmo_fsm_inst_update_id_f_sanitize(struct osmo_fsm_inst *fi, char
replace_with, const char *fmt, ...);
const char *osmo_fsm_event_name(struct osmo_fsm *fsm, uint32_t event);
const char *osmo_fsm_inst_name(struct osmo_fsm_inst *fi);
diff --git a/include/osmocom/core/utils.h b/include/osmocom/core/utils.h
index 08735fd..f27359c 100644
--- a/include/osmocom/core/utils.h
+++ b/include/osmocom/core/utils.h
@@ -140,6 +140,7 @@
bool osmo_identifier_valid(const char *str);
bool osmo_separated_identifiers_valid(const char *str, const char *sep_chars);
+void osmo_identifier_sanitize_buf(char *str, const char *sep_chars, char
replace_with);
const char *osmo_escape_str(const char *str, int len);
char *osmo_escape_str_buf2(char *buf, size_t bufsize, const char *str, int
in_len);
diff --git a/src/fsm.c b/src/fsm.c
index b6912c6..c32767b 100644
--- a/src/fsm.c
+++ b/src/fsm.c
@@ -364,6 +364,35 @@
return 0;
}
+/*! Change id of the FSM instance using a string format, and ensuring a valid
id.
+ * Replace any characters that are not permitted as FSM identifier with
replace_with.
+ * \param[in] fi FSM instance.
+ * \param[in] replace_with Character to use instead of non-permitted FSM id
characters.
+ * Make sure to choose a legal character, e.g. '-'.
+ * \param[in] fmt format string to compose new ID.
+ * \param[in] ... variable argument list for format string.
+ * \returns 0 if the ID was updated, otherwise -EINVAL.
+ */
+int osmo_fsm_inst_update_id_f_sanitize(struct osmo_fsm_inst *fi, char
replace_with, const char *fmt, ...)
+{
+ char *id = NULL;
+ va_list ap;
+ int rc;
+
+ if (!fmt)
+ return osmo_fsm_inst_update_id(fi, NULL);
+
+ va_start(ap, fmt);
+ id = talloc_vasprintf(fi, fmt, ap);
+ va_end(ap);
+
+ osmo_identifier_sanitize_buf(id, NULL, replace_with);
+
+ rc = osmo_fsm_inst_update_id(fi, id);
+ talloc_free(id);
+ return rc;
+}
+
/*! allocate a new instance of a specified FSM
* \param[in] fsm Descriptor of the FSM
* \param[in] ctx talloc context from which to allocate memory
diff --git a/src/utils.c b/src/utils.c
index 6116d3a..896e917 100644
--- a/src/utils.c
+++ b/src/utils.c
@@ -553,6 +553,8 @@
return true;
}
+static const char osmo_identifier_illegal_chars[] = ".,
{}[]()<>|~\\^`'\"?=;/+*&%$#!";
+
/*! Determine if a given identifier is valid, i.e. doesn't contain illegal
chars
* \param[in] str String to validate
* \param[in] sep_chars Permitted separation characters between identifiers.
@@ -561,7 +563,6 @@
bool osmo_separated_identifiers_valid(const char *str, const char *sep_chars)
{
/* characters that are illegal in names */
- static const char illegal_chars[] = "., {}[]()<>|~\\^`'\"?=;/+*&%$#!";
unsigned int i;
size_t len;
@@ -578,7 +579,7 @@
if (!isprint((int)str[i]))
return false;
/* check for some explicit reserved control characters */
- if (strchr(illegal_chars, str[i]))
+ if (strchr(osmo_identifier_illegal_chars, str[i]))
return false;
}
@@ -594,6 +595,25 @@
return osmo_separated_identifiers_valid(str, NULL);
}
+/*! Replace characters in the given string buffer so that it is guaranteed to
pass osmo_separated_identifiers_valid().
+ * To guarantee passing osmo_separated_identifiers_valid(), replace_with must
not itself be an illegal character. If in
+ * doubt, use '-'.
+ * \param[inout] str Identifier to sanitize, must be nul terminated and in a
writable buffer.
+ * \param[in] sep_chars Additional characters that are allowed besides
osmo_identifier_illegal_chars.
+ * \param[in] replace_with Replace any illegal characters with this character.
+ */
+void osmo_identifier_sanitize_buf(char *str, const char *sep_chars, char
replace_with)
+{
+ char *pos;
+ if (!str)
+ return;
+ for (pos = str; *pos; pos++) {
+ if (strchr(osmo_identifier_illegal_chars, *pos)
+ || (sep_chars && strchr(sep_chars, *pos)))
+ *pos = replace_with;
+ }
+}
+
/*! Like osmo_escape_str_buf2, but with unusual ordering of arguments, and may
sometimes return string constants instead
* of writing to buf for error cases or empty input.
* Most *_buf() functions have the buffer and size as first arguments, here
the arguments are last.
--
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Gerrit-Project: libosmocore
Gerrit-Branch: master
Gerrit-MessageType: merged
Gerrit-Change-Id: Ia40a6f3b2243c95fe428a080b938e11d8ab771a7
Gerrit-Change-Number: 13574
Gerrit-PatchSet: 4
Gerrit-Owner: Neels Hofmeyr <[email protected]>
Gerrit-Reviewer: Harald Welte <[email protected]>
Gerrit-Reviewer: Jenkins Builder (1000002)
Gerrit-Reviewer: Neels Hofmeyr <[email protected]>
