From 5f7f45a64bdb9353f15b945db4ad2564b4b28ab2 Mon Sep 17 00:00:00 2001
From: Jakub Hrozek <jhrozek@redhat.com>
Date: Mar 27 2017 07:56:03 +0000
Subject: UTIL: Add type-specific getsetters to sss_iobuf


The KCM responder receives its input as unstructured data. To make the
parsing easier, this commit adds several type-specific getsetters to the
iobuf module.

Reviewed-by: Michal Židek <mzidek@redhat.com>
Reviewed-by: Simo Sorce <simo@redhat.com>

---

diff --git a/src/util/sss_iobuf.c b/src/util/sss_iobuf.c
index 900418b..fc288d2 100644
--- a/src/util/sss_iobuf.c
+++ b/src/util/sss_iobuf.c
@@ -184,6 +184,25 @@ errno_t sss_iobuf_read(struct sss_iobuf *iobuf,
     return EOK;
 }
 
+errno_t sss_iobuf_read_len(struct sss_iobuf *iobuf,
+                           size_t len,
+                           uint8_t *_buf)
+{
+    size_t read;
+    errno_t ret;
+
+    ret = sss_iobuf_read(iobuf, len, _buf, &read);
+    if (ret != EOK) {
+        return ret;
+    }
+
+    if (read != len) {
+        return ENOBUFS;
+    }
+
+    return EOK;
+}
+
 errno_t sss_iobuf_write_len(struct sss_iobuf *iobuf,
                             uint8_t *buf,
                             size_t len)
@@ -203,3 +222,92 @@ errno_t sss_iobuf_write_len(struct sss_iobuf *iobuf,
 
     return EOK;
 }
+
+errno_t sss_iobuf_read_uint32(struct sss_iobuf *iobuf,
+                              uint32_t *_val)
+{
+    SAFEALIGN_COPY_UINT32_CHECK(_val, iobuf_ptr(iobuf),
+                                iobuf->capacity, &iobuf->dp);
+    return EOK;
+}
+
+errno_t sss_iobuf_read_int32(struct sss_iobuf *iobuf,
+                             int32_t *_val)
+{
+    SAFEALIGN_COPY_INT32_CHECK(_val, iobuf_ptr(iobuf),
+                               iobuf->capacity, &iobuf->dp);
+    return EOK;
+}
+
+errno_t sss_iobuf_write_uint32(struct sss_iobuf *iobuf,
+                               uint32_t val)
+{
+    errno_t ret;
+
+    ret = ensure_bytes(iobuf, sizeof(uint32_t));
+    if (ret != EOK) {
+        return ret;
+    }
+
+    SAFEALIGN_SETMEM_UINT32(iobuf_ptr(iobuf), val, &iobuf->dp);
+    return EOK;
+}
+
+errno_t sss_iobuf_write_int32(struct sss_iobuf *iobuf,
+                              int32_t val)
+{
+    errno_t ret;
+
+    ret = ensure_bytes(iobuf, sizeof(int32_t));
+    if (ret != EOK) {
+        return ret;
+    }
+
+    SAFEALIGN_SETMEM_INT32(iobuf_ptr(iobuf), val, &iobuf->dp);
+    return EOK;
+}
+
+errno_t sss_iobuf_read_stringz(struct sss_iobuf *iobuf,
+                               const char **_out)
+{
+    uint8_t *end;
+    size_t len;
+
+    if (iobuf == NULL) {
+        return EINVAL;
+    }
+
+    if (_out == NULL) {
+        return EINVAL;
+    }
+
+    *_out = NULL;
+
+    end = memchr(iobuf_ptr(iobuf), '\0', sss_iobuf_get_size(iobuf));
+    if (end == NULL) {
+        return EINVAL;
+    }
+
+    len = end + 1 - iobuf_ptr(iobuf);
+    if (sss_iobuf_get_size(iobuf) < len) {
+        return EINVAL;
+    }
+
+    *_out = (const char *) iobuf_ptr(iobuf);
+    iobuf->dp += len;
+    return EOK;
+}
+
+errno_t sss_iobuf_write_stringz(struct sss_iobuf *iobuf,
+                                const char *str)
+{
+    if (iobuf == NULL || str == NULL) {
+        return EINVAL;
+    }
+
+    SAFEALIGN_MEMCPY_CHECK(iobuf_ptr(iobuf),
+                           str, strlen(str)+1,
+                           sss_iobuf_get_size(iobuf),
+                           &iobuf->dp);
+    return EOK;
+}
diff --git a/src/util/sss_iobuf.h b/src/util/sss_iobuf.h
index 900faaa..cc3dfd1 100644
--- a/src/util/sss_iobuf.h
+++ b/src/util/sss_iobuf.h
@@ -96,6 +96,22 @@ errno_t sss_iobuf_read(struct sss_iobuf *iobuf,
                        size_t *_read);
 
 /*
+ * @brief Read an exact number of bytes from an IO buffer
+ *
+ * Read exactly len bytes from an IO buffer. If the buffer contains fewer
+ * bytes than len, ENOBUFS is returned.
+ *
+ * @param[in]  iobuf        The IO buffer to read from
+ * @param[in]  len          The maximum number of bytes to read
+ * @param[out] _buf         The buffer to read data into from iobuf
+ *
+ * @return EOK on success, errno otherwise
+ */
+errno_t sss_iobuf_read_len(struct sss_iobuf *iobuf,
+                           size_t len,
+                           uint8_t *_buf);
+
+/*
  * @brief Write into an IO buffer
  *
  * Attempts to write len bytes into the iobuf. If the capacity is exceeded,
@@ -115,4 +131,21 @@ errno_t sss_iobuf_write_len(struct sss_iobuf *iobuf,
                             uint8_t *buf,
                             size_t len);
 
+errno_t sss_iobuf_read_uint32(struct sss_iobuf *iobuf,
+                              uint32_t *_val);
+
+errno_t sss_iobuf_write_uint32(struct sss_iobuf *iobuf,
+                               uint32_t val);
+
+errno_t sss_iobuf_read_int32(struct sss_iobuf *iobuf,
+                             int32_t *_val);
+
+errno_t sss_iobuf_write_int32(struct sss_iobuf *iobuf,
+                              int32_t val);
+
+errno_t sss_iobuf_read_stringz(struct sss_iobuf *iobuf,
+                               const char **_out);
+
+errno_t sss_iobuf_write_stringz(struct sss_iobuf *iobuf,
+                                const char *str);
 #endif /* __SSS_IOBUF_H_ */