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-rw-r--r--lib/content_encoding.c155
1 files changed, 102 insertions, 53 deletions
diff --git a/lib/content_encoding.c b/lib/content_encoding.c
index c2ba26972..01a155246 100644
--- a/lib/content_encoding.c
+++ b/lib/content_encoding.c
@@ -73,14 +73,17 @@
typedef enum {
ZLIB_UNINIT, /* uninitialized */
ZLIB_INIT, /* initialized */
+ ZLIB_INFLATING, /* Inflating started. */
ZLIB_GZIP_HEADER, /* reading gzip header */
+ ZLIB_GZIP_TRAILER, /* reading gzip trailer */
ZLIB_GZIP_INFLATING, /* inflating gzip stream */
ZLIB_INIT_GZIP /* initialized in transparent gzip mode */
} zlibInitState;
/* Writer parameters. */
typedef struct {
- zlibInitState zlib_init; /* zlib init state */
+ zlibInitState zlib_init; /* zlib init state */
+ uInt trailerlen; /* Remaining trailer byte count. */
z_stream z; /* State structure for zlib. */
} zlib_params;
@@ -130,80 +133,120 @@ exit_zlib(struct connectdata *conn,
return result;
}
-static CURLcode
-inflate_stream(struct connectdata *conn, contenc_writer *writer)
+static CURLcode process_trailer(struct connectdata *conn, zlib_params *zp)
+{
+ z_stream *z = &zp->z;
+ CURLcode result = CURLE_OK;
+ uInt len = z->avail_in < zp->trailerlen? z->avail_in: zp->trailerlen;
+
+ /* Consume expected trailer bytes. Terminate stream if exhausted.
+ Issue an error if unexpected bytes follow. */
+
+ zp->trailerlen -= len;
+ z->avail_in -= len;
+ z->next_in += len;
+ if(z->avail_in)
+ result = CURLE_WRITE_ERROR;
+ if(result || !zp->trailerlen)
+ result = exit_zlib(conn, z, &zp->zlib_init, result);
+ else {
+ /* Only occurs for gzip with zlib < 1.2.0.4. */
+ zp->zlib_init = ZLIB_GZIP_TRAILER;
+ }
+ return result;
+}
+
+static CURLcode inflate_stream(struct connectdata *conn,
+ contenc_writer *writer, zlibInitState started)
{
zlib_params *zp = (zlib_params *) &writer->params;
- int allow_restart = 1;
z_stream *z = &zp->z; /* zlib state structure */
uInt nread = z->avail_in;
Bytef *orig_in = z->next_in;
int status; /* zlib status */
+ bool done = FALSE;
CURLcode result = CURLE_OK; /* Curl_client_write status */
char *decomp; /* Put the decompressed data here. */
+ /* Check state. */
+ if(zp->zlib_init != ZLIB_INIT &&
+ zp->zlib_init != ZLIB_INFLATING &&
+ zp->zlib_init != ZLIB_INIT_GZIP &&
+ zp->zlib_init != ZLIB_GZIP_INFLATING)
+ return exit_zlib(conn, z, &zp->zlib_init, CURLE_WRITE_ERROR);
+
/* Dynamically allocate a buffer for decompression because it's uncommonly
large to hold on the stack */
decomp = malloc(DSIZ);
- if(decomp == NULL) {
+ if(decomp == NULL)
return exit_zlib(conn, z, &zp->zlib_init, CURLE_OUT_OF_MEMORY);
- }
/* because the buffer size is fixed, iteratively decompress and transfer to
- the client via client_write. */
- for(;;) {
- if(z->avail_in == 0) {
- free(decomp);
- return result;
- }
+ the client via downstream_write function. */
+ while(!done) {
+ done = TRUE;
/* (re)set buffer for decompressed output for every iteration */
z->next_out = (Bytef *) decomp;
z->avail_out = DSIZ;
- status = inflate(z, Z_SYNC_FLUSH);
- if(status == Z_OK || status == Z_STREAM_END) {
- allow_restart = 0;
- result = Curl_unencode_write(conn, writer->downstream, decomp,
- DSIZ - z->avail_out);
- /* if !CURLE_OK, clean up, return */
- if(result) {
- free(decomp);
- return exit_zlib(conn, z, &zp->zlib_init, result);
- }
-
- /* Done? clean up, return */
- if(status == Z_STREAM_END) {
- free(decomp);
- return exit_zlib(conn, z, &zp->zlib_init, result);
+ status = inflate(z, Z_BLOCK);
+
+ /* Flush output data if some. */
+ if(z->avail_out != DSIZ) {
+ if(status == Z_OK || status == Z_STREAM_END) {
+ zp->zlib_init = started; /* Data started. */
+ result = Curl_unencode_write(conn, writer->downstream, decomp,
+ DSIZ - z->avail_out);
+ if(result) {
+ exit_zlib(conn, z, &zp->zlib_init, result);
+ break;
+ }
}
-
- /* Done with these bytes, exit */
-
- /* status is always Z_OK at this point! */
- continue;
}
- else if(allow_restart && status == Z_DATA_ERROR) {
+
+ /* Dispatch by inflate() status. */
+ switch(status) {
+ case Z_OK:
+ /* Always loop: there may be unflushed latched data in zlib state. */
+ done = FALSE;
+ break;
+ case Z_BUF_ERROR:
+ /* No more data to flush: just exit loop. */
+ break;
+ case Z_STREAM_END:
+ result = process_trailer(conn, zp);
+ break;
+ case Z_DATA_ERROR:
/* some servers seem to not generate zlib headers, so this is an attempt
to fix and continue anyway */
-
- (void) inflateEnd(z); /* don't care about the return code */
- if(inflateInit2(z, -MAX_WBITS) != Z_OK) {
- free(decomp);
- zp->zlib_init = ZLIB_UNINIT; /* inflateEnd() already called. */
- return exit_zlib(conn, z, &zp->zlib_init, process_zlib_error(conn, z));
+ if(zp->zlib_init == ZLIB_INIT) {
+ /* Do not use inflateReset2(): only available since zlib 1.2.3.4. */
+ (void) inflateEnd(z); /* don't care about the return code */
+ if(inflateInit2(z, -MAX_WBITS) == Z_OK) {
+ z->next_in = orig_in;
+ z->avail_in = nread;
+ zp->zlib_init = ZLIB_INFLATING;
+ done = FALSE;
+ break;
+ }
+ zp->zlib_init = ZLIB_UNINIT; /* inflateEnd() already called. */
}
- z->next_in = orig_in;
- z->avail_in = nread;
- allow_restart = 0;
- continue;
- }
- else { /* Error; exit loop, handle below */
- free(decomp);
- return exit_zlib(conn, z, &zp->zlib_init, process_zlib_error(conn, z));
+ /* FALLTHROUGH */
+ default:
+ result = exit_zlib(conn, z, &zp->zlib_init, process_zlib_error(conn, z));
+ break;
}
}
- /* UNREACHED */
+ free(decomp);
+
+ /* We're about to leave this call so the `nread' data bytes won't be seen
+ again. If we are in a state that would wrongly allow restart in raw mode
+ at the next call, assume output has already started. */
+ if(nread && zp->zlib_init == ZLIB_INIT)
+ zp->zlib_init = started; /* Cannot restart anymore. */
+
+ return result;
}
@@ -239,7 +282,7 @@ static CURLcode deflate_unencode_write(struct connectdata *conn,
z->avail_in = (uInt) nbytes;
/* Now uncompress the data */
- return inflate_stream(conn, writer);
+ return inflate_stream(conn, writer, ZLIB_INFLATING);
}
static void deflate_close_writer(struct connectdata *conn,
@@ -283,11 +326,12 @@ static CURLcode gzip_init_writer(struct connectdata *conn,
zp->zlib_init = ZLIB_INIT_GZIP; /* Transparent gzip decompress state */
}
else {
- /* we must parse the gzip header ourselves */
+ /* we must parse the gzip header and trailer ourselves */
if(inflateInit2(z, -MAX_WBITS) != Z_OK) {
return process_zlib_error(conn, z);
}
- zp->zlib_init = ZLIB_INIT; /* Initial call state */
+ zp->trailerlen = 8; /* A CRC-32 and a 32-bit input size (RFC 1952, 2.2) */
+ zp->zlib_init = ZLIB_INIT; /* Initial call state */
}
return CURLE_OK;
@@ -389,7 +433,7 @@ static CURLcode gzip_unencode_write(struct connectdata *conn,
z->next_in = (Bytef *) buf;
z->avail_in = (uInt) nbytes;
/* Now uncompress the data */
- return inflate_stream(conn, writer);
+ return inflate_stream(conn, writer, ZLIB_INIT_GZIP);
}
#ifndef OLD_ZLIB_SUPPORT
@@ -482,6 +526,11 @@ static CURLcode gzip_unencode_write(struct connectdata *conn,
}
break;
+ case ZLIB_GZIP_TRAILER:
+ z->next_in = (Bytef *) buf;
+ z->avail_in = (uInt) nbytes;
+ return process_trailer(conn, zp);
+
case ZLIB_GZIP_INFLATING:
default:
/* Inflating stream state */
@@ -496,7 +545,7 @@ static CURLcode gzip_unencode_write(struct connectdata *conn,
}
/* We've parsed the header, now uncompress the data */
- return inflate_stream(conn, writer);
+ return inflate_stream(conn, writer, ZLIB_GZIP_INFLATING);
#endif
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-26 07:55:12 +0000