/*
* Copyright (C) the libgit2 contributors. All rights reserved.
*
* This file is part of libgit2, distributed under the GNU GPL v2 with
* a Linking Exception. For full terms see the included COPYING file.
*/
#include "common.h"
#include "git2/types.h"
#include "git2/errors.h"
#include "git2/refs.h"
#include "git2/revwalk.h"
#include "smart.h"
#include "util.h"
#include "netops.h"
#include "posix.h"
#include "buffer.h"
#include <ctype.h>
#define PKT_LEN_SIZE 4
static const char pkt_done_str[] = "0009done\n";
static const char pkt_flush_str[] = "0000";
static const char pkt_have_prefix[] = "0032have ";
static const char pkt_want_prefix[] = "0032want ";
static int flush_pkt(git_pkt **out)
{
git_pkt *pkt;
pkt = git__malloc(sizeof(git_pkt));
GITERR_CHECK_ALLOC(pkt);
pkt->type = GIT_PKT_FLUSH;
*out = pkt;
return 0;
}
/* the rest of the line will be useful for multi_ack and multi_ack_detailed */
static int ack_pkt(git_pkt **out, const char *line, size_t len)
{
git_pkt_ack *pkt;
pkt = git__calloc(1, sizeof(git_pkt_ack));
GITERR_CHECK_ALLOC(pkt);
pkt->type = GIT_PKT_ACK;
if (git__prefixncmp(line, len, "ACK "))
goto out_err;
line += 4;
len -= 4;
if (len < GIT_OID_HEXSZ || git_oid_fromstr(&pkt->oid, line) < 0)
goto out_err;
line += GIT_OID_HEXSZ;
len -= GIT_OID_HEXSZ;
if (len && line[0] == ' ') {
line++;
len--;
if (!git__prefixncmp(line, len, "continue"))
pkt->status = GIT_ACK_CONTINUE;
else if (!git__prefixncmp(line, len, "common"))
pkt->status = GIT_ACK_COMMON;
else if (!git__prefixncmp(line, len, "ready"))
pkt->status = GIT_ACK_READY;
else
goto out_err;
}
*out = (git_pkt *) pkt;
return 0;
out_err:
giterr_set(GITERR_NET, "error parsing ACK pkt-line");
git__free(pkt);
return -1;
}
static int nak_pkt(git_pkt **out)
{
git_pkt *pkt;
pkt = git__malloc(sizeof(git_pkt));
GITERR_CHECK_ALLOC(pkt);
pkt->type = GIT_PKT_NAK;
*out = pkt;
return 0;
}
static int comment_pkt(git_pkt **out, const char *line, size_t len)
{
git_pkt_comment *pkt;
size_t alloclen;
GITERR_CHECK_ALLOC_ADD(&alloclen, sizeof(git_pkt_comment), len);
GITERR_CHECK_ALLOC_ADD(&alloclen, alloclen, 1);
pkt = git__malloc(alloclen);
GITERR_CHECK_ALLOC(pkt);
pkt->type = GIT_PKT_COMMENT;
memcpy(pkt->comment, line, len);
pkt->comment[len] = '\0';
*out = (git_pkt *) pkt;
return 0;
}
static int err_pkt(git_pkt **out, const char *line, size_t len)
{
git_pkt_err *pkt = NULL;
size_t alloclen;
/* Remove "ERR " from the line */
if (git__prefixncmp(line, len, "ERR "))
goto out_err;
line += 4;
len -= 4;
GITERR_CHECK_ALLOC_ADD(&alloclen, sizeof(git_pkt_progress), len);
GITERR_CHECK_ALLOC_ADD(&alloclen, alloclen, 1);
pkt = git__malloc(alloclen);
GITERR_CHECK_ALLOC(pkt);
pkt->type = GIT_PKT_ERR;
pkt->len = len;
memcpy(pkt->error, line, len);
pkt->error[len] = '\0';
*out = (git_pkt *) pkt;
return 0;
out_err:
giterr_set(GITERR_NET, "error parsing ERR pkt-line");
git__free(pkt);
return -1;
}
static int data_pkt(git_pkt **out, const char *line, size_t len)
{
git_pkt_data *pkt;
size_t alloclen;
line++;
len--;
GITERR_CHECK_ALLOC_ADD(&alloclen, sizeof(git_pkt_progress), len);
pkt = git__malloc(alloclen);
GITERR_CHECK_ALLOC(pkt);
pkt->type = GIT_PKT_DATA;
pkt->len = len;
memcpy(pkt->data, line, len);
*out = (git_pkt *) pkt;
return 0;
}
static int sideband_progress_pkt(git_pkt **out, const char *line, size_t len)
{
git_pkt_progress *pkt;
size_t alloclen;
line++;
len--;
GITERR_CHECK_ALLOC_ADD(&alloclen, sizeof(git_pkt_progress), len);
pkt = git__malloc(alloclen);
GITERR_CHECK_ALLOC(pkt);
pkt->type = GIT_PKT_PROGRESS;
pkt->len = len;
memcpy(pkt->data, line, len);
*out = (git_pkt *) pkt;
return 0;
}
static int sideband_error_pkt(git_pkt **out, const char *line, size_t len)
{
git_pkt_err *pkt;
size_t alloc_len;
line++;
len--;
GITERR_CHECK_ALLOC_ADD(&alloc_len, sizeof(git_pkt_err), len);
GITERR_CHECK_ALLOC_ADD(&alloc_len, alloc_len, 1);
pkt = git__malloc(alloc_len);
GITERR_CHECK_ALLOC(pkt);
pkt->type = GIT_PKT_ERR;
pkt->len = (int)len;
memcpy(pkt->error, line, len);
pkt->error[len] = '\0';
*out = (git_pkt *)pkt;
return 0;
}
/*
* Parse an other-ref line.
*/
static int ref_pkt(git_pkt **out, const char *line, size_t len)
{
git_pkt_ref *pkt;
size_t alloclen;
pkt = git__calloc(1, sizeof(git_pkt_ref));
GITERR_CHECK_ALLOC(pkt);
pkt->type = GIT_PKT_REF;
if (len < GIT_OID_HEXSZ || git_oid_fromstr(&pkt->head.oid, line) < 0)
goto out_err;
line += GIT_OID_HEXSZ;
len -= GIT_OID_HEXSZ;
if (git__prefixncmp(line, len, " "))
goto out_err;
line++;
len--;
if (!len)
goto out_err;
if (line[len - 1] == '\n')
--len;
GITERR_CHECK_ALLOC_ADD(&alloclen, len, 1);
pkt->head.name = git__malloc(alloclen);
GITERR_CHECK_ALLOC(pkt->head.name);
memcpy(pkt->head.name, line, len);
pkt->head.name[len] = '\0';
if (strlen(pkt->head.name) < len)
pkt->capabilities = strchr(pkt->head.name, '\0') + 1;
*out = (git_pkt *)pkt;
return 0;
out_err:
giterr_set(GITERR_NET, "error parsing REF pkt-line");
if (pkt)
git__free(pkt->head.name);
git__free(pkt);
return -1;
}
static int ok_pkt(git_pkt **out, const char *line, size_t len)
{
git_pkt_ok *pkt;
size_t alloc_len;
pkt = git__malloc(sizeof(*pkt));
GITERR_CHECK_ALLOC(pkt);
pkt->type = GIT_PKT_OK;
if (git__prefixncmp(line, len, "ok "))
goto out_err;
line += 3;
len -= 3;
if (line[len - 1] == '\n')
--len;
GITERR_CHECK_ALLOC_ADD(&alloc_len, len, 1);
pkt->ref = git__malloc(alloc_len);
GITERR_CHECK_ALLOC(pkt->ref);
memcpy(pkt->ref, line, len);
pkt->ref[len] = '\0';
*out = (git_pkt *)pkt;
return 0;
out_err:
giterr_set(GITERR_NET, "error parsing OK pkt-line");
git__free(pkt);
return -1;
}
static int ng_pkt(git_pkt **out, const char *line, size_t len)
{
git_pkt_ng *pkt;
const char *ptr, *eol;
size_t alloclen;
pkt = git__malloc(sizeof(*pkt));
GITERR_CHECK_ALLOC(pkt);
pkt->ref = NULL;
pkt->type = GIT_PKT_NG;
eol = line + len;
if (git__prefixncmp(line, len, "ng "))
goto out_err;
line += 3;
if (!(ptr = memchr(line, ' ', eol - line)))
goto out_err;
len = ptr - line;
GITERR_CHECK_ALLOC_ADD(&alloclen, len, 1);
pkt->ref = git__malloc(alloclen);
GITERR_CHECK_ALLOC(pkt->ref);
memcpy(pkt->ref, line, len);
pkt->ref[len] = '\0';
line = ptr + 1;
if (line >= eol)
goto out_err;
if (!(ptr = memchr(line, '\n', eol - line)))
goto out_err;
len = ptr - line;
GITERR_CHECK_ALLOC_ADD(&alloclen, len, 1);
pkt->msg = git__malloc(alloclen);
GITERR_CHECK_ALLOC(pkt->msg);
memcpy(pkt->msg, line, len);
pkt->msg[len] = '\0';
*out = (git_pkt *)pkt;
return 0;
out_err:
giterr_set(GITERR_NET, "invalid packet line");
git__free(pkt->ref);
git__free(pkt);
return -1;
}
static int unpack_pkt(git_pkt **out, const char *line, size_t len)
{
git_pkt_unpack *pkt;
pkt = git__malloc(sizeof(*pkt));
GITERR_CHECK_ALLOC(pkt);
pkt->type = GIT_PKT_UNPACK;
if (!git__prefixncmp(line, len, "unpack ok"))
pkt->unpack_ok = 1;
else
pkt->unpack_ok = 0;
*out = (git_pkt *)pkt;
return 0;
}
static int parse_len(size_t *out, const char *line, size_t linelen)
{
char num[PKT_LEN_SIZE + 1];
int i, k, error;
int32_t len;
const char *num_end;
/* Not even enough for the length */
if (linelen < PKT_LEN_SIZE)
return GIT_EBUFS;
memcpy(num, line, PKT_LEN_SIZE);
num[PKT_LEN_SIZE] = '\0';
for (i = 0; i < PKT_LEN_SIZE; ++i) {
if (!isxdigit(num[i])) {
/* Make sure there are no special characters before passing to error message */
for (k = 0; k < PKT_LEN_SIZE; ++k) {
if(!isprint(num[k])) {
num[k] = '.';
}
}
giterr_set(GITERR_NET, "invalid hex digit in length: '%s'", num);
return -1;
}
}
if ((error = git__strntol32(&len, num, PKT_LEN_SIZE, &num_end, 16)) < 0)
return error;
if (len < 0)
return -1;
*out = (size_t) len;
return 0;
}
/*
* As per the documentation, the syntax is:
*
* pkt-line = data-pkt / flush-pkt
* data-pkt = pkt-len pkt-payload
* pkt-len = 4*(HEXDIG)
* pkt-payload = (pkt-len -4)*(OCTET)
* flush-pkt = "0000"
*
* Which means that the first four bytes are the length of the line,
* in ASCII hexadecimal (including itself)
*/
int git_pkt_parse_line(
git_pkt **pkt, const char **endptr, const char *line, size_t linelen)
{
int error;
size_t len;
if ((error = parse_len(&len, line, linelen)) < 0) {
/*
* If we fail to parse the length, it might be
* because the server is trying to send us the
* packfile already or because we do not yet have
* enough data.
*/
if (error == GIT_EBUFS)
;
else if (!git__prefixncmp(line, linelen, "PACK"))
giterr_set(GITERR_NET, "unexpected pack file");
else
giterr_set(GITERR_NET, "bad packet length");
return error;
}
/*
* Make sure there is enough in the buffer to satisfy
* this line.
*/
if (linelen < len)
return GIT_EBUFS;
/*
* The length has to be exactly 0 in case of a flush
* packet or greater than PKT_LEN_SIZE, as the decoded
* length includes its own encoded length of four bytes.
*/
if (len != 0 && len < PKT_LEN_SIZE)
return GIT_ERROR;
line += PKT_LEN_SIZE;
/*
* The Git protocol does not specify empty lines as part
* of the protocol. Not knowing what to do with an empty
* line, we should return an error upon hitting one.
*/
if (len == PKT_LEN_SIZE) {
giterr_set_str(GITERR_NET, "Invalid empty packet");
return GIT_ERROR;
}
if (len == 0) { /* Flush pkt */
*endptr = line;
return flush_pkt(pkt);
}
len -= PKT_LEN_SIZE; /* the encoded length includes its own size */
if (*line == GIT_SIDE_BAND_DATA)
error = data_pkt(pkt, line, len);
else if (*line == GIT_SIDE_BAND_PROGRESS)
error = sideband_progress_pkt(pkt, line, len);
else if (*line == GIT_SIDE_BAND_ERROR)
error = sideband_error_pkt(pkt, line, len);
else if (!git__prefixncmp(line, len, "ACK"))
error = ack_pkt(pkt, line, len);
else if (!git__prefixncmp(line, len, "NAK"))
error = nak_pkt(pkt);
else if (!git__prefixncmp(line, len, "ERR"))
error = err_pkt(pkt, line, len);
else if (*line == '#')
error = comment_pkt(pkt, line, len);
else if (!git__prefixncmp(line, len, "ok"))
error = ok_pkt(pkt, line, len);
else if (!git__prefixncmp(line, len, "ng"))
error = ng_pkt(pkt, line, len);
else if (!git__prefixncmp(line, len, "unpack"))
error = unpack_pkt(pkt, line, len);
else
error = ref_pkt(pkt, line, len);
*endptr = line + len;
return error;
}
void git_pkt_free(git_pkt *pkt)
{
if (pkt->type == GIT_PKT_REF) {
git_pkt_ref *p = (git_pkt_ref *) pkt;
git__free(p->head.name);
git__free(p->head.symref_target);
}
if (pkt->type == GIT_PKT_OK) {
git_pkt_ok *p = (git_pkt_ok *) pkt;
git__free(p->ref);
}
if (pkt->type == GIT_PKT_NG) {
git_pkt_ng *p = (git_pkt_ng *) pkt;
git__free(p->ref);
git__free(p->msg);
}
git__free(pkt);
}
int git_pkt_buffer_flush(git_buf *buf)
{
return git_buf_put(buf, pkt_flush_str, strlen(pkt_flush_str));
}
static int buffer_want_with_caps(const git_remote_head *head, transport_smart_caps *caps, git_buf *buf)
{
git_buf str = GIT_BUF_INIT;
char oid[GIT_OID_HEXSZ +1] = {0};
size_t len;
/* Prefer multi_ack_detailed */
if (caps->multi_ack_detailed)
git_buf_puts(&str, GIT_CAP_MULTI_ACK_DETAILED " ");
else if (caps->multi_ack)
git_buf_puts(&str, GIT_CAP_MULTI_ACK " ");
/* Prefer side-band-64k if the server supports both */
if (caps->side_band_64k)
git_buf_printf(&str, "%s ", GIT_CAP_SIDE_BAND_64K);
else if (caps->side_band)
git_buf_printf(&str, "%s ", GIT_CAP_SIDE_BAND);
if (caps->include_tag)
git_buf_puts(&str, GIT_CAP_INCLUDE_TAG " ");
if (caps->thin_pack)
git_buf_puts(&str, GIT_CAP_THIN_PACK " ");
if (caps->ofs_delta)
git_buf_puts(&str, GIT_CAP_OFS_DELTA " ");
if (git_buf_oom(&str))
return -1;
len = strlen("XXXXwant ") + GIT_OID_HEXSZ + 1 /* NUL */ +
git_buf_len(&str) + 1 /* LF */;
if (len > 0xffff) {
giterr_set(GITERR_NET,
"tried to produce packet with invalid length %" PRIuZ, len);
return -1;
}
git_buf_grow_by(buf, len);
git_oid_fmt(oid, &head->oid);
git_buf_printf(buf,
"%04xwant %s %s\n", (unsigned int)len, oid, git_buf_cstr(&str));
git_buf_free(&str);
GITERR_CHECK_ALLOC_BUF(buf);
return 0;
}
/*
* All "want" packets have the same length and format, so what we do
* is overwrite the OID each time.
*/
int git_pkt_buffer_wants(
const git_remote_head * const *refs,
size_t count,
transport_smart_caps *caps,
git_buf *buf)
{
size_t i = 0;
const git_remote_head *head;
if (caps->common) {
for (; i < count; ++i) {
head = refs[i];
if (!head->local)
break;
}
if (buffer_want_with_caps(refs[i], caps, buf) < 0)
return -1;
i++;
}
for (; i < count; ++i) {
char oid[GIT_OID_HEXSZ];
head = refs[i];
if (head->local)
continue;
git_oid_fmt(oid, &head->oid);
git_buf_put(buf, pkt_want_prefix, strlen(pkt_want_prefix));
git_buf_put(buf, oid, GIT_OID_HEXSZ);
git_buf_putc(buf, '\n');
if (git_buf_oom(buf))
return -1;
}
return git_pkt_buffer_flush(buf);
}
int git_pkt_buffer_have(git_oid *oid, git_buf *buf)
{
char oidhex[GIT_OID_HEXSZ + 1];
memset(oidhex, 0x0, sizeof(oidhex));
git_oid_fmt(oidhex, oid);
return git_buf_printf(buf, "%s%s\n", pkt_have_prefix, oidhex);
}
int git_pkt_buffer_done(git_buf *buf)
{
return git_buf_puts(buf, pkt_done_str);
}