Adding upstream version 9.1.upstream/9.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 497 insertions, 0 deletions

diff --git a/lib/stream.h b/lib/stream.h
new file mode 100644
index 0000000..85eebb4
--- /dev/null
+++ b/lib/stream.h
@@ -0,0 +1,497 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Packet interface
+ * Copyright (C) 1999 Kunihiro Ishiguro
+ */
+
+#ifndef _ZEBRA_STREAM_H
+#define _ZEBRA_STREAM_H
+
+#include <pthread.h>
+
+#include "frratomic.h"
+#include "mpls.h"
+#include "prefix.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*
+ * A stream is an arbitrary buffer, whose contents generally are assumed to
+ * be in network order.
+ *
+ * A stream has the following attributes associated with it:
+ *
+ * - size: the allocated, invariant size of the buffer.
+ *
+ * - getp: the get position marker, denoting the offset in the stream where
+ *         the next read (or 'get') will be from. This getp marker is
+ *         automatically adjusted when data is read from the stream, the
+ *         user may also manipulate this offset as they wish, within limits
+ *         (see below)
+ *
+ * - endp: the end position marker, denoting the offset in the stream where
+ *         valid data ends, and if the user attempted to write (or
+ *         'put') data where that data would be written (or 'put') to.
+ *
+ * These attributes are all size_t values.
+ *
+ * Constraints:
+ *
+ * 1. getp can never exceed endp
+ *
+ * - hence if getp is equal to endp, there is no more valid data that can be
+ *   gotten from the stream (though, the user may reposition getp to earlier in
+ *   the stream, if they wish).
+ *
+ * 2. endp can never exceed size
+ *
+ * - hence, if endp is equal to size, then the stream is full, and no more
+ *   data can be written to the stream.
+ *
+ * In other words the following must always be true, and the stream
+ * abstraction is allowed internally to assert that the following property
+ * holds true for a stream, as and when it wishes:
+ *
+ *        getp <= endp <= size
+ *
+ * It is the users responsibility to ensure this property is never violated.
+ *
+ * A stream therefore can be thought of like this:
+ *
+ * 	---------------------------------------------------
+ * 	|XXXXXXXXXXXXXXXXXXXXXXXX                         |
+ * 	---------------------------------------------------
+ *               ^               ^                        ^
+ *               getp            endp                     size
+ *
+ * This shows a stream containing data (shown as 'X') up to the endp offset.
+ * The stream is empty from endp to size. Without adjusting getp, there are
+ * still endp-getp bytes of valid data to be read from the stream.
+ *
+ * Methods are provided to get and put to/from the stream, as well as
+ * retrieve the values of the 3 markers and manipulate the getp marker.
+ *
+ * Note:
+ * At the moment, newly allocated streams are zero filled. Hence, one can
+ * use stream_forward_endp() to effectively create arbitrary zero-fill
+ * padding. However, note that stream_reset() does *not* zero-out the
+ * stream. This property should **not** be relied upon.
+ *
+ * Best practice is to use stream_put (<stream *>, NULL, <size>) to zero out
+ * any part of a stream which isn't otherwise written to.
+ */
+
+/* Stream buffer. */
+struct stream {
+	struct stream *next;
+
+	/*
+	 * Remainder is ***private*** to stream
+	 * direct access is frowned upon!
+	 * Use the appropriate functions/macros
+	 */
+	size_t getp;	       /* next get position */
+	size_t endp;	       /* last valid data position */
+	size_t size;	       /* size of data segment */
+	unsigned char data[];  /* data pointer */
+};
+
+/* First in first out queue structure. */
+struct stream_fifo {
+	/* lock for mt-safe operations */
+	pthread_mutex_t mtx;
+
+	/* number of streams in this fifo */
+	atomic_size_t count;
+#if defined DEV_BUILD
+	atomic_size_t max_count;
+#endif
+
+	struct stream *head;
+	struct stream *tail;
+};
+
+/* Utility macros. */
+#define STREAM_SIZE(S)  ((S)->size)
+/* number of bytes which can still be written */
+#define STREAM_WRITEABLE(S) ((S)->size - (S)->endp)
+/* number of bytes still to be read */
+#define STREAM_READABLE(S) ((S)->endp - (S)->getp)
+
+#define STREAM_CONCAT_REMAIN(S1, S2, size) ((size) - (S1)->endp - (S2)->endp)
+
+/* this macro is deprecated, but not slated for removal anytime soon */
+#define STREAM_DATA(S)  ((S)->data)
+
+/* Stream prototypes.
+ * For stream_{put,get}S, the S suffix mean:
+ *
+ * c: character (unsigned byte)
+ * w: word (two bytes)
+ * l: long (two words)
+ * q: quad (four words)
+ */
+extern struct stream *stream_new(size_t);
+extern void stream_free(struct stream *);
+/* Copy 'src' into 'dest', returns 'dest' */
+extern struct stream *stream_copy(struct stream *dest,
+				  const struct stream *src);
+extern struct stream *stream_dup(const struct stream *s);
+
+extern size_t stream_resize_inplace(struct stream **sptr, size_t newsize);
+
+extern size_t stream_get_getp(const struct stream *s);
+extern size_t stream_get_endp(const struct stream *s);
+extern size_t stream_get_size(const struct stream *s);
+
+/**
+ * Create a new stream structure; copy offset bytes from s1 to the new
+ * stream; copy s2 data to the new stream; copy rest of s1 data to the
+ * new stream.
+ */
+extern struct stream *stream_dupcat(const struct stream *s1,
+				    const struct stream *s2, size_t offset);
+
+extern void stream_set_getp(struct stream *, size_t);
+extern void stream_set_endp(struct stream *, size_t);
+extern void stream_forward_getp(struct stream *, size_t);
+extern bool stream_forward_getp2(struct stream *, size_t);
+extern void stream_rewind_getp(struct stream *s, size_t size);
+extern bool stream_rewind_getp2(struct stream *s, size_t size);
+extern void stream_forward_endp(struct stream *, size_t);
+extern bool stream_forward_endp2(struct stream *, size_t);
+
+/* steam_put: NULL source zeroes out size_t bytes of stream */
+extern void stream_put(struct stream *, const void *, size_t);
+extern int stream_putc(struct stream *, uint8_t);
+extern int stream_putc_at(struct stream *, size_t, uint8_t);
+extern int stream_putw(struct stream *, uint16_t);
+extern int stream_putw_at(struct stream *, size_t, uint16_t);
+extern int stream_put3(struct stream *, uint32_t);
+extern int stream_put3_at(struct stream *, size_t, uint32_t);
+extern int stream_putl(struct stream *, uint32_t);
+extern int stream_putl_at(struct stream *, size_t, uint32_t);
+extern int stream_putq(struct stream *, uint64_t);
+extern int stream_putq_at(struct stream *, size_t, uint64_t);
+extern int stream_put_ipv4(struct stream *, uint32_t);
+extern int stream_put_in_addr(struct stream *s, const struct in_addr *addr);
+extern bool stream_put_ipaddr(struct stream *s, struct ipaddr *ip);
+extern int stream_put_in_addr_at(struct stream *s, size_t putp,
+				 const struct in_addr *addr);
+extern int stream_put_in6_addr_at(struct stream *s, size_t putp,
+				  const struct in6_addr *addr);
+extern int stream_put_prefix_addpath(struct stream *s, const struct prefix *p,
+				     bool addpath_capable,
+				     uint32_t addpath_tx_id);
+extern int stream_put_prefix(struct stream *s, const struct prefix *p);
+extern int stream_put_labeled_prefix(struct stream *, const struct prefix *,
+				     mpls_label_t *, bool addpath_capable,
+				     uint32_t addpath_tx_id);
+extern void stream_get(void *, struct stream *, size_t);
+extern bool stream_get2(void *data, struct stream *s, size_t size);
+extern void stream_get_from(void *, struct stream *, size_t, size_t);
+extern uint8_t stream_getc(struct stream *);
+extern bool stream_getc2(struct stream *s, uint8_t *byte);
+extern uint8_t stream_getc_from(struct stream *, size_t);
+extern uint16_t stream_getw(struct stream *);
+extern bool stream_getw2(struct stream *s, uint16_t *word);
+extern uint16_t stream_getw_from(struct stream *, size_t);
+extern uint32_t stream_get3(struct stream *);
+extern uint32_t stream_get3_from(struct stream *, size_t);
+extern uint32_t stream_getl(struct stream *);
+extern bool stream_getl2(struct stream *s, uint32_t *l);
+extern uint32_t stream_getl_from(struct stream *, size_t);
+extern uint64_t stream_getq(struct stream *);
+extern uint64_t stream_getq_from(struct stream *, size_t);
+bool stream_getq2(struct stream *s, uint64_t *q);
+extern uint32_t stream_get_ipv4(struct stream *);
+extern bool stream_get_ipaddr(struct stream *s, struct ipaddr *ip);
+
+/* IEEE-754 floats */
+extern float stream_getf(struct stream *);
+extern double stream_getd(struct stream *);
+extern int stream_putf(struct stream *, float);
+extern int stream_putd(struct stream *, double);
+
+#undef stream_read
+#undef stream_write
+
+/* Deprecated: assumes blocking I/O.  Will be removed.
+   Use stream_read_try instead.  */
+extern int stream_read(struct stream *, int, size_t);
+
+/* Read up to size bytes into the stream.
+   Return code:
+     >0: number of bytes read
+     0: end-of-file
+     -1: fatal error
+     -2: transient error, should retry later (i.e. EAGAIN or EINTR)
+   This is suitable for use with non-blocking file descriptors.
+ */
+extern ssize_t stream_read_try(struct stream *s, int fd, size_t size);
+
+extern ssize_t stream_recvmsg(struct stream *s, int fd, struct msghdr *,
+			      int flags, size_t size);
+extern ssize_t stream_recvfrom(struct stream *s, int fd, size_t len, int flags,
+			       struct sockaddr *from, socklen_t *fromlen);
+extern size_t stream_write(struct stream *, const void *, size_t);
+
+/* reset the stream. See Note above */
+extern void stream_reset(struct stream *);
+extern int stream_flush(struct stream *, int);
+extern int stream_empty(struct stream *); /* is the stream empty? */
+
+/* debugging */
+extern void stream_hexdump(const struct stream *s);
+
+/**
+ * Reorganize the buffer data so it can fit more. This function is normally
+ * called right after stream data is consumed so we can read more data
+ * (the functions that consume data start with `stream_get*()` and macros
+ * `STREAM_GET*()`).
+ *
+ * \param s stream pointer.
+ */
+extern void stream_pulldown(struct stream *s);
+
+/* deprecated */
+extern uint8_t *stream_pnt(struct stream *);
+
+/*
+ * Operations on struct stream_fifo.
+ *
+ * Each function has a safe variant, which ensures that the operation performed
+ * is atomic with respect to the operations performed by all other safe
+ * variants. In other words, the safe variants lock the stream_fifo's mutex
+ * before performing their action. These are provided for convenience when
+ * using stream_fifo in a multithreaded context, to alleviate the need for the
+ * caller to implement their own synchronization around the stream_fifo.
+ *
+ * The following functions do not have safe variants. The caller must ensure
+ * that these operations are performed safely in a multithreaded context:
+ * - stream_fifo_new
+ * - stream_fifo_free
+ */
+
+/*
+ * Create a new stream_fifo.
+ *
+ * Returns:
+ *    newly created stream_fifo
+ */
+extern struct stream_fifo *stream_fifo_new(void);
+
+/*
+ * Init or re-init an on-stack fifo. This allows use of a fifo struct without
+ * requiring a malloc/free cycle.
+ * Note well that the fifo must be de-inited with the 'fifo_deinit' api.
+ */
+void stream_fifo_init(struct stream_fifo *fifo);
+
+/*
+ * Deinit an on-stack fifo.
+ */
+void stream_fifo_deinit(struct stream_fifo *fifo);
+
+/*
+ * Push a stream onto a stream_fifo.
+ *
+ * fifo
+ *    the stream_fifo to push onto
+ *
+ * s
+ *    the stream to push onto the stream_fifo
+ */
+extern void stream_fifo_push(struct stream_fifo *fifo, struct stream *s);
+extern void stream_fifo_push_safe(struct stream_fifo *fifo, struct stream *s);
+
+/*
+ * Pop a stream off a stream_fifo.
+ *
+ * fifo
+ *    the stream_fifo to pop from
+ *
+ * Returns:
+ *    the next stream in the stream_fifo
+ */
+extern struct stream *stream_fifo_pop(struct stream_fifo *fifo);
+extern struct stream *stream_fifo_pop_safe(struct stream_fifo *fifo);
+
+/*
+ * Retrieve the next stream from a stream_fifo without popping it.
+ *
+ * fifo
+ *    the stream_fifo to operate on
+ *
+ * Returns:
+ *    the next stream that would be returned from stream_fifo_pop
+ */
+extern struct stream *stream_fifo_head(struct stream_fifo *fifo);
+extern struct stream *stream_fifo_head_safe(struct stream_fifo *fifo);
+
+/*
+ * Remove all streams from a stream_fifo.
+ *
+ * fifo
+ *    the stream_fifo to clean
+ */
+extern void stream_fifo_clean(struct stream_fifo *fifo);
+extern void stream_fifo_clean_safe(struct stream_fifo *fifo);
+
+/*
+ * Retrieve number of streams on a stream_fifo.
+ *
+ * fifo
+ *    the stream_fifo to retrieve the count for
+ *
+ * Returns:
+ *    the number of streams on the stream_fifo
+ */
+extern size_t stream_fifo_count_safe(struct stream_fifo *fifo);
+
+/*
+ * Free a stream_fifo.
+ *
+ * Calls stream_fifo_clean, then deinitializes the stream_fifo and frees it.
+ *
+ * fifo
+ *    the stream_fifo to free
+ */
+extern void stream_fifo_free(struct stream_fifo *fifo);
+
+/* This is here because "<< 24" is particularly problematic in C.
+ * This is because the left operand of << is integer-promoted, which means
+ * an uint8_t gets converted into a *signed* int.  Shifting into the sign
+ * bit of a signed int is theoretically undefined behaviour, so - the left
+ * operand needs to be cast to unsigned.
+ *
+ * This is not a problem for 16- or 8-bit values (they don't reach the sign
+ * bit), for 64-bit values (you need to cast them anyway), and neither for
+ * encoding (because it's downcasted.)
+ */
+static inline const uint8_t *ptr_get_be64(const uint8_t *ptr, uint64_t *out)
+{
+	uint32_t tmp1, tmp2;
+
+	memcpy(&tmp1, ptr, sizeof(tmp1));
+	memcpy(&tmp2, ptr + sizeof(tmp1), sizeof(tmp1));
+
+	*out = (((uint64_t)ntohl(tmp1)) << 32) | ntohl(tmp2);
+
+	return ptr + 8;
+}
+
+static inline const uint8_t *ptr_get_be32(const uint8_t *ptr, uint32_t *out)
+{
+	uint32_t tmp;
+
+	memcpy(&tmp, ptr, sizeof(tmp));
+	*out = ntohl(tmp);
+	return ptr + 4;
+}
+
+static inline uint8_t *ptr_get_be16(uint8_t *ptr, uint16_t *out)
+{
+	uint16_t tmp;
+
+	memcpy(&tmp, ptr, sizeof(tmp));
+	*out = ntohs(tmp);
+
+	return ptr + 2;
+}
+
+/*
+ * so Normal stream_getX functions assert.  Which is anathema
+ * to keeping a daemon up and running when something goes south
+ * Provide a stream_getX2 functions that do not assert.
+ * In addition provide these macro's that upon failure
+ * goto stream_failure.  This is modeled upon some NL_XX
+ * macros in the linux kernel.
+ *
+ * This change allows for proper memory freeing
+ * after we've detected an error.
+ *
+ * In the future we will be removing the assert in
+ * the stream functions but we need a transition
+ * plan.
+ */
+#define STREAM_GETC(S, P)                                                      \
+	do {                                                                   \
+		uint8_t _pval;                                                 \
+		if (!stream_getc2((S), &_pval))                                \
+			goto stream_failure;                                   \
+		(P) = _pval;                                                   \
+	} while (0)
+
+#define STREAM_GETW(S, P)                                                      \
+	do {                                                                   \
+		uint16_t _pval;                                                \
+		if (!stream_getw2((S), &_pval))                                \
+			goto stream_failure;                                   \
+		(P) = _pval;                                                   \
+	} while (0)
+
+#define STREAM_GETL(S, P)                                                      \
+	do {                                                                   \
+		uint32_t _pval;                                                \
+		if (!stream_getl2((S), &_pval))                                \
+			goto stream_failure;                                   \
+		(P) = _pval;                                                   \
+	} while (0)
+
+#define STREAM_GETF(S, P)                                                      \
+	do {                                                                   \
+		union {                                                        \
+			float r;                                               \
+			uint32_t d;                                            \
+		} _pval;                                                       \
+		if (!stream_getl2((S), &_pval.d))                              \
+			goto stream_failure;                                   \
+		(P) = _pval.r;                                                 \
+	} while (0)
+
+#define STREAM_GETQ(S, P)                                                      \
+	do {                                                                   \
+		uint64_t _pval;                                                \
+		if (!stream_getq2((S), &_pval))                                \
+			goto stream_failure;                                   \
+		(P) = _pval;                                                   \
+	} while (0)
+
+#define STREAM_GET_IPADDR(S, P)                                                \
+	do {                                                                   \
+		if (!stream_get_ipaddr((S), (P)))                              \
+			goto stream_failure;                                   \
+	} while (0)
+
+#define STREAM_GET(P, STR, SIZE)                                               \
+	do {                                                                   \
+		if (!stream_get2((P), (STR), (SIZE)))                          \
+			goto stream_failure;                                   \
+	} while (0)
+
+#define STREAM_FORWARD_GETP(STR, SIZE)                                         \
+	do {                                                                   \
+		if (!stream_forward_getp2((STR), (SIZE)))                      \
+			goto stream_failure;                                   \
+	} while (0)
+
+#define STREAM_REWIND_GETP(STR, SIZE)                                          \
+	do {                                                                   \
+		if (!stream_rewind_getp2((STR), (SIZE)))                       \
+			goto stream_failure;                                   \
+	} while (0)
+
+#define STREAM_FORWARD_ENDP(STR, SIZE)                                         \
+	do {                                                                   \
+		if (!stream_forward_endp2((STR), (SIZE)))                      \
+			goto stream_failure;                                   \
+	} while (0)
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _ZEBRA_STREAM_H */