dedup

commit da5196be59c4f03fd81127900dd1b1afdbdfa34f
parent 1c0530ef5bf190a62ca8ce7c9b3ae14702b44a7f
Author: sin <sin@2f30.org>
Date:   Tue, 14 May 2019 13:33:06 +0300

Split initmdhead() into plaintext/encrypted variants

Diffstat:
M
snap.c
 | 
143
++++++++++++++++++++++++++++++++++++++++++-------------------------------------

1 file changed, 76 insertions(+), 67 deletions(-)
diff --git a/snap.c b/snap.c
@@ -94,84 +94,93 @@ packshdr(unsigned char *buf, struct shdr *shdr)
 }
 
 static int
+loadmdnone(struct sctx *sctx, int first)
+{
+	struct mdnode *mdnode;
+
+	mdnode = calloc(1, sizeof(*mdnode));
+	if (mdnode == NULL) {
+		seterr("calloc: %s", strerror(errno));
+		return -1;
+	}
+
+	if (xread(sctx->fd, mdnode->md, MDSIZE) != MDSIZE) {
+		seterr("failed to read block hash: %s", strerror(errno));
+		return -1;
+	}
+
+	TAILQ_INSERT_TAIL(&sctx->mdhead, mdnode, e);
+	return 0;
+}
+
+static int
+loadmdcrypto(struct sctx *sctx, int first)
+{
+	unsigned char buf[MDSIZE + crypto_secretstream_xchacha20poly1305_ABYTES];
+	unsigned char hdr[SHDRSIZE];
+	static crypto_secretstream_xchacha20poly1305_state state;
+	struct mdnode *mdnode;
+	struct shdr *shdr;
+
+	shdr = &sctx->shdr;
+	packshdr(hdr, shdr);
+	if (first && crypto_secretstream_xchacha20poly1305_init_pull(&state,
+	                                                             shdr->header,
+	                                                             param.key) < 0) {
+		seterr("invalid crypto header");
+		return -1;
+	}
+
+	if (xread(sctx->fd, buf, sizeof(buf)) != sizeof(buf)) {
+		seterr("failed to read block hash: %s", strerror(errno));
+		return -1;
+	}
+
+	mdnode = calloc(1, sizeof(*mdnode));
+	if (mdnode == NULL) {
+		seterr("calloc: %s", strerror(errno));
+		return -1;
+	}
+
+	if (crypto_secretstream_xchacha20poly1305_pull(&state, mdnode->md, NULL,
+	                                               NULL, buf, sizeof(buf),
+	                                               hdr, sizeof(hdr)) < 0) {
+		free(mdnode);
+		seterr("authentication failed");
+		return -1;
+	}
+
+	TAILQ_INSERT_TAIL(&sctx->mdhead, mdnode, e);
+	return 0;
+}
+
+static int
 initmdhead(struct sctx *sctx)
 {
 	struct shdr *shdr;
+	int (*fn)(struct sctx *, int);
 	uint64_t i;
 
+	if (!sctx->crypto)
+		fn = loadmdnone;
+	else
+		fn = loadmdcrypto;
+
 	shdr = &sctx->shdr;
-	if (sctx->crypto) {
-		unsigned char ad[SHDRSIZE];
-		crypto_secretstream_xchacha20poly1305_state state;
-		struct shdr *shdr;
-
-		shdr = &sctx->shdr;
-		packshdr(ad, shdr);
-
-		if (crypto_secretstream_xchacha20poly1305_init_pull(&state,
-		                                                    shdr->header,
-		                                                    param.key) < 0) {
-			seterr("invalid crypto header");
-			return -1;
-		}
+	for (i = 0; i < shdr->nbd; i++) {
+		if ((*fn)(sctx, i == 0) == 0)
+			continue;
 
-		for (i = 0; i < shdr->nbd; i++) {
-			unsigned char buf[MDSIZE + crypto_secretstream_xchacha20poly1305_ABYTES];
-			unsigned char md[MDSIZE];
-			struct mdnode *mdnode;
-			unsigned char tag;
-
-			if (xread(sctx->fd, buf, sizeof(buf)) != sizeof(buf)) {
-				seterr("failed to read block hash: %s", strerror(errno));
-				goto err0;
-			}
-
-			if (crypto_secretstream_xchacha20poly1305_pull(&state, md, NULL, &tag,
-			                                               buf, sizeof(buf),
-			                                               ad, sizeof(ad)) < 0) {
-				seterr("authentication failed");
-				goto err0;
-			}
-
-			mdnode = calloc(1, sizeof(*mdnode));
-			if (mdnode == NULL) {
-				seterr("calloc: %s", strerror(errno));
-				goto err0;
-			}
-			memcpy(mdnode->md, md, MDSIZE);
-			TAILQ_INSERT_TAIL(&sctx->mdhead, mdnode, e);
-		}
-	} else {
-		for (i = 0; i < shdr->nbd; i++) {
-			unsigned char md[MDSIZE];
+		while (!TAILQ_EMPTY(&sctx->mdhead)) {
 			struct mdnode *mdnode;
 
-			if (xread(sctx->fd, md, MDSIZE) != MDSIZE) {
-				seterr("failed to read block hash: %s", strerror(errno));
-				goto err0;
-			}
-
-			mdnode = calloc(1, sizeof(*mdnode));
-			if (mdnode == NULL) {
-				seterr("calloc: %s", strerror(errno));
-				goto err0;
-			}
-			memcpy(mdnode->md, md, MDSIZE);
-			TAILQ_INSERT_TAIL(&sctx->mdhead, mdnode, e);
+			mdnode = TAILQ_FIRST(&sctx->mdhead);
+			TAILQ_REMOVE(&sctx->mdhead, mdnode, e);
+			free(mdnode);
 		}
+		return -1;
 	}
 	return 0;
-
-err0:
-	/* Cleanup */
-	while (!TAILQ_EMPTY(&sctx->mdhead)) {
-		struct mdnode *mdnode;
-
-		mdnode = TAILQ_FIRST(&sctx->mdhead);
-		TAILQ_REMOVE(&sctx->mdhead, mdnode, e);
-		free(mdnode);
-	}
-	return -1;
 }
 
 int
@@ -486,7 +495,7 @@ sclose(struct sctx *sctx)
 	if (ssync(sctx) < 0)
 		return -1;
 
-	/* Cleanup */
+	/* Free block hash list */
 	while (!TAILQ_EMPTY(&sctx->mdhead)) {
 		struct mdnode *mdnode;