X-Git-Url: https://pd.if.org/git/?a=blobdiff_plain;ds=sidebyside;f=crypto%2Fbuffer.c;fp=crypto%2Fbuffer.c;h=a65c21ed2e3dd0a8fa66d67287460be5fd6a6d6c;hb=66bc25938679f1d6a1d1200f329093d82a5e99b4;hp=0000000000000000000000000000000000000000;hpb=a52ee0733f420ca20224049260d6fc5cf7d8f621;p=zpackage

diff --git a/crypto/buffer.c b/crypto/buffer.c
new file mode 100644
index 0000000..a65c21e
--- /dev/null
+++ b/crypto/buffer.c
@@ -0,0 +1,257 @@
+#define _POSIX_C_SOURCE 200809L
+
+#include <string.h>
+#include <errno.h>
+
+#include "tlse.h"
+#include "buffer.h"
+
+void tls_buffer_init(struct tls_buffer *buffer, size_t initial) {
+	buffer->buffer = 0;
+	buffer->len = 0;
+	buffer->size = 0;
+	buffer->error = 0;
+	if (initial) {
+		errno = 0;
+		buffer->buffer = malloc(initial);
+		if (buffer->buffer) {
+			memset(buffer->buffer, 0, initial);
+			buffer->size = initial;
+		} else {
+			buffer->error = errno;
+		}
+	}
+}
+
+void tls_buffer_compact(struct tls_buffer *b) {
+	void *new;
+
+	if (b->error || b->size == b->len) {
+		return;
+	}
+
+	errno = 0;
+	new = realloc(b->buffer, b->len);
+
+	if (new == NULL) {
+		b->error = errno;
+		return;
+	}
+
+	b->buffer = new;
+	return;
+}
+
+/* makes sure there's at least need bytes free */
+void tls_buffer_expand(struct tls_buffer *buf, size_t need) {
+	size_t want;
+
+	if (buf->error) {
+		return;
+	}
+
+	want = buf->len + need;
+
+	if (want <= buf->size) {
+		return;
+	}
+
+	errno = 0;
+	char *new = realloc(buf->buffer, want);
+	if (new) {
+		buf->buffer = new;
+		buf->size = want;
+		memset(buf->buffer + buf->len, 0, buf->size - buf->len);
+	} else {
+		buf->error = errno;
+	}
+}
+
+void tls_buffer_free(struct tls_buffer *buffer) {
+	/* TODO only zero out memory if it's "secure" buffer */
+	if (buffer->buffer && buffer->len) {
+		memset(buffer->buffer, 0, buffer->len);
+	}
+	free(buffer->buffer);
+	tls_buffer_init(buffer, 0);
+}
+
+void tls_buffer_set(struct tls_buffer *buffer, int ch) {
+	/* TODO only zero out memory if it's "secure" buffer */
+	if (buffer->buffer && buffer->size) {
+		memset(buffer->buffer, ch, buffer->size);
+	}
+}
+
+void tls_buffer_append(struct tls_buffer *buffer, const unsigned char *bytes, size_t n) {
+	tls_buffer_expand(buffer, n);
+
+	if (buffer->error || !bytes) {
+		return;
+	}
+
+	memcpy(buffer->buffer + buffer->len, bytes, n);
+	buffer->len += n;
+}
+
+void tls_buffer_append16(struct tls_buffer *buffer, uint16_t n) {
+	tls_buffer_expand(buffer, 2);
+
+	if (buffer->error) {
+		return;
+	}
+
+	buffer->buffer[buffer->len++] = (n >> 8) & 0xff;
+	buffer->buffer[buffer->len++] = n & 0xff;
+}
+
+void tls_buffer_append24(struct tls_buffer *buffer, uint32_t n) {
+	tls_buffer_expand(buffer, 3);
+
+	if (buffer->error) {
+		return;
+	}
+
+	buffer->buffer[buffer->len++] = (n >> 16) & 0xff;
+	buffer->buffer[buffer->len++] = (n >> 8) & 0xff;
+	buffer->buffer[buffer->len++] = n & 0xff;
+}
+
+void tls_buffer_append_byte(struct tls_buffer *buffer, uint8_t n) {
+	tls_buffer_expand(buffer, 1);
+
+	if (buffer->error) {
+		return;
+	}
+
+	buffer->buffer[buffer->len++] = n & 0xff;
+}
+
+void tls_buffer_write16(struct tls_buffer *buffer, uint16_t n, size_t at) {
+	if (at+2 > buffer->size) {
+		tls_buffer_expand(buffer, at+2 - buffer->size);
+	}
+
+	if (buffer->error) {
+		return;
+	}
+
+	buffer->buffer[at] = (n >> 8) & 0xff;
+	buffer->buffer[at+1] = n & 0xff;
+
+	if (at+2 > buffer->len) {
+		buffer->len = at + 2;
+	}
+}
+
+uint16_t tls_buffer_read16(struct tls_buffer *buffer, size_t at) {
+	uint16_t res = 0;
+
+	if (buffer->error || at+2 < buffer->len) {
+		return 0;
+	}
+
+	res = (buffer->buffer[at] << 8) + buffer->buffer[at+1];
+	return res;
+}
+
+uint64_t tls_buffer_readbe(struct tls_buffer *buffer, int bytes, size_t at) {
+	uint16_t res = 0;
+	int i;
+
+	if (buffer->error || at+bytes < buffer->len) {
+		return 0;
+	}
+
+	for (i=0; i<bytes; i++) {
+		res <<= 8;
+		res += buffer->buffer[at+i];
+	}
+
+	return res;
+}
+
+void tls_buffer_writebe(struct tls_buffer *buffer, int bytes, size_t at, uint64_t val) {
+	int i;
+	if (at+bytes > buffer->size) {
+		tls_buffer_expand(buffer, at+bytes - buffer->size);
+	}
+
+	if (buffer->error) {
+		return;
+	}
+
+	for (i=bytes-1; i>=0; i--) {
+		buffer->buffer[at+i] = val & 0xff;
+		val >>= 8;
+	}
+
+	return;
+}
+
+
+void tls_buffer_shift(struct tls_buffer *buffer, size_t n) {
+	if (buffer->error) {
+		return;
+	}
+
+	if (buffer->len < n) {
+		n = buffer->len;
+	}
+
+	if (n) {
+		memmove(buffer->buffer, buffer->buffer + n, buffer->len - n);
+		memset(buffer->buffer + buffer->len - n, 0, n);
+#if 0
+		fprintf(stderr, "memmove(%p, %p, %zu)\n", buffer->buffer,
+				buffer->buffer+n, buffer->len - n);
+		fprintf(stderr, "memset(%p, %d, %zu)\n", buffer->buffer+n,
+				0, n);
+#endif
+
+		buffer->len -= n;
+	}
+}
+
+/* make room at the beginning */
+void tls_buffer_unshift(struct tls_buffer *buffer, size_t n) {
+	tls_buffer_expand(buffer, n);
+
+	if (buffer->error) {
+		return;
+	}
+
+	memmove(buffer->buffer + n, buffer->buffer, n);
+	memset(buffer->buffer, 0, n);
+}
+
+#if 0
+uint32_t tls_buffer_next3(struct tls_buffer_reader *rb) {
+	uint32_t r;
+
+	r = tls_buffer_readbe(rb, 3, rb->cursor);
+	rb->cursor += 3;
+	return r;
+}
+
+uint16_t tls_buffer_next2(struct tls_buffer_reader *rb) {
+	uint16_t r;
+
+	r = tls_buffer_readbe(rb, 2, rb->cursor);
+	rb->cursor += 2;
+	return r;
+}
+
+uint8_t tls_buffer_next(struct tls_buffer_reader *rb) {
+	uint16_t r;
+
+	r = tls_buffer_readbe(rb, 2, rb->cursor);
+	rb->cursor += 2;
+
+}
+
+void tls_buffer_nextn(struct tls_buffer_reader *rb, unsigned char *b, size_t n) {
+	tls_buffer_read(rb, b, n, rb->cursor);
+	rb->cursor += n;
+}
+#endif