/*
* Copyright (c) 2019 Ori Bernstein <ori@openbsd.org>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <sys/types.h>
#include <sys/queue.h>
#include <sys/uio.h>
#include <sys/time.h>
#include <sys/stat.h>
#include <sys/syslimits.h>
#include <stdint.h>
#include <errno.h>
#include <imsg.h>
#include <limits.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <sha1.h>
#include <fcntl.h>
#include <zlib.h>
#include <err.h>
#include "got_error.h"
#include "got_object.h"
#include "got_path.h"
#include "got_version.h"
#include "got_lib_sha1.h"
#include "got_lib_delta.h"
#include "got_lib_object.h"
#include "got_lib_object_parse.h"
#include "got_lib_privsep.h"
#ifndef nitems
#define nitems(_a) (sizeof((_a)) / sizeof((_a)[0]))
#endif
#define GOT_PKTMAX 65536
struct got_object *indexed;
static int chattygit;
static char *fetchbranch;
static char *upstream = "origin";
static struct got_object_id zhash = {.sha1={0}};
static char*
strip(char *ref)
{
return ref;
}
int
readn(int fd, void *buf, size_t n)
{
ssize_t r, off;
off = 0;
while (off != n) {
r = read(fd, buf + off, n - off);
if (r < 0)
return -1;
if (r == 0)
return off;
off += r;
}
return off;
}
int
flushpkt(int fd)
{
if(chattygit)
fprintf(stderr, "writepkt: 0000\n");
return write(fd, "0000", 4);
}
int
readpkt(int fd, char *buf, int nbuf)
{
char len[5];
char *e;
int n, r;
if(readn(fd, len, 4) == -1){
return -1;
}
len[4] = 0;
n = strtol(len, &e, 16);
if(n == 0){
if(chattygit)
fprintf(stderr, "readpkt: 0000\n");
return 0;
}
if(e != len + 4 || n <= 4)
err(1, "invalid packet line length");
n -= 4;
if(n >= nbuf)
err(1, "buffer too small");
if((r = readn(fd, buf, n)) != n)
return -1;
buf[n] = 0;
if(chattygit)
fprintf(stderr, "readpkt: %s:\t%.*s\n", len, nbuf, buf);
return n;
}
int
writepkt(int fd, char *buf, int nbuf)
{
char len[5];
int i;
if (snprintf(len, sizeof(len), "%04x", nbuf + 4) >= sizeof(len))
return -1;
if(write(fd, len, 4) != 4)
return -1;
if(write(fd, buf, nbuf) != nbuf)
return -1;
if(chattygit){
fprintf(stderr, "writepkt: %s:\t", len);
fwrite(buf, 1, nbuf, stderr);
for(i = 0; i < nbuf; i++){
if(isprint(buf[i]))
fputc(buf[i], stderr);
}
}
return 0;
}
int
got_resolve_remote_ref(struct got_object_id *id, char *ref)
{
char buf[128], *s;
int r, f;
ref = strip(ref);
if(!got_parse_sha1_digest(id->sha1, ref))
return 0;
/* Slightly special handling: translate remote refs to local ones. */
if (strcmp(ref, "HEAD") == 0) {
if(snprintf(buf, sizeof(buf), ".git/HEAD") >= sizeof(buf))
return -1;
} else if(strstr(ref, "refs/heads") == ref) {
ref += strlen("refs/heads");
if(snprintf(buf, sizeof(buf),
".git/refs/remotes/%s/%s", upstream, ref) >= sizeof(buf))
return -1;
} else if(strstr(ref, "refs/tags") == ref) {
ref += strlen("refs/tags");
if(snprintf(buf, sizeof(buf),
".git/refs/tags/%s/%s", upstream, ref) >= sizeof(buf))
return -1;
} else {
return -1;
}
r = -1;
s = strip(buf);
if((f = open(s, O_RDONLY)) == -1)
goto err;
if(readn(f, buf, sizeof(buf)) < 40)
goto err;
if(!got_parse_sha1_digest(id->sha1, buf))
goto err;
err:
close(f);
if(r == -1 && strstr(buf, "ref:") == buf)
return got_resolve_remote_ref(id, buf + strlen("ref:"));
return r;
}
static int
got_check_pack_hash(int fd, size_t sz, uint8_t *hcomp)
{
SHA1_CTX ctx;
uint8_t hexpect[SHA1_DIGEST_LENGTH];
char s1[SHA1_DIGEST_STRING_LENGTH + 1];
char s2[SHA1_DIGEST_STRING_LENGTH + 1];
uint8_t buf[32*1024];
ssize_t n, r, nr;
if(sz < 28)
return -1;
n = 0;
SHA1Init(&ctx);
while(n < sz - 20){
nr = sizeof(buf);
if(sz - n - 20 < sizeof(buf))
nr = sz - n - 20;
r = readn(fd, buf, nr);
if(r != nr)
return -1;
SHA1Update(&ctx, buf, nr);
n += r;
}
SHA1Final(hcomp, &ctx);
if(readn(fd, hexpect, sizeof(hexpect)) != sizeof(hexpect))
errx(1, "truncated packfile");
if(memcmp(hcomp, hexpect, SHA1_DIGEST_LENGTH) != 0){
got_sha1_digest_to_str(hcomp, s1, sizeof(s1));
got_sha1_digest_to_str(hexpect, s2, sizeof(s2));
printf("hash mismatch %s != %s\n", s1, s2);
return -1;
}
return 0;
}
int
got_has_object(struct got_object_id *obj)
{
return 0;
}
/*static */int
got_make_pack_dir(char *path)
{
char s[128];
char *p;
if(snprintf(s, sizeof(s), "%s", path) >= sizeof(s))
return -1;
for(p=strchr(s+1, '/'); p; p=strchr(p+1, '/')){
*p = 0;
if (mkdir(s, 0755) == -1)
if(errno != EEXIST)
return -1;
*p = '/';
}
return 0;
}
static int
got_match_branch(char *br, char *pat)
{
char name[128];
if(strstr(pat, "refs/heads") == pat) {
if (snprintf(name, sizeof(name), "%s", pat) >= sizeof(name))
return -1;
} else if(strstr(pat, "heads")) {
if (snprintf(name, sizeof(name), "refs/%s", pat) >= sizeof(name))
return -1;
} else {
if (snprintf(name, sizeof(name), "refs/heads/%s", pat) >= sizeof(name))
return -1;
}
return strcmp(br, name) == 0;
}
static const struct got_error *
got_tokenize_refline(char **tokens, char *line, int len)
{
const struct got_error *err = NULL;
char *p;
size_t i, n = 0;
const int maxtokens = 3;
for (i = 0; i < maxtokens; i++)
tokens[i] = NULL;
for (i = 0; n < len && i < maxtokens; i++) {
while (isspace(*line)) {
line++;
n++;
}
p = line;
while (*line != '\0' &&
(!isspace(*line) || i == maxtokens - 1)) {
line++;
n++;
}
tokens[i] = strndup(p, line - p);
if (tokens[i] == NULL) {
err = got_error_from_errno("strndup");
goto done;
}
/* Skip \0 field-delimiter at end of token. */
while (line[0] == '\0' && n < len) {
line++;
n++;
}
}
if (i <= 2)
err = got_error(GOT_ERR_NOT_REF);
done:
if (err) {
int j;
for (j = 0; j < i; j++)
free(tokens[j]);
tokens[j] = NULL;
}
return err;
}
struct got_capability {
const char *key;
const char *value;
};
static const struct got_capability got_capabilities[] = {
#if 0 /* got-index-pack is not ready for this */
{ "ofs-delta", NULL },
#endif
{ "agent", "got/" GOT_VERSION_STR },
};
static const struct got_error *
match_capability(char **my_capabilities, const char *capa,
const struct got_capability *mycapa)
{
char *equalsign;
char *s;
equalsign = strchr(capa, '=');
if (equalsign) {
if (strncmp(capa, mycapa->key, equalsign - capa) != 0)
return NULL;
} else {
if (strcmp(capa, mycapa->key) != 0)
return NULL;
}
if (asprintf(&s, "%s%s%s%s%s",
*my_capabilities != NULL ? *my_capabilities : "",
*my_capabilities != NULL ? " " : "",
mycapa->key,
mycapa->value != NULL ? "=" : "",
mycapa->value != NULL? mycapa->value : "") == -1)
return got_error_from_errno("asprintf");
free(*my_capabilities);
*my_capabilities = s;
return NULL;
}
static const struct got_error *
add_symref(struct got_pathlist_head *symrefs, const char *capa)
{
const struct got_error *err = NULL;
char *colon, *name = NULL, *target = NULL;
/* Need at least "A:B" */
if (strlen(capa) < 3)
return NULL;
colon = strchr(capa, ':');
if (colon == NULL)
return NULL;
*colon = '\0';
name = strdup(capa);
if (name == NULL)
return got_error_from_errno("strdup");
target = strdup(colon + 1);
if (target == NULL) {
err = got_error_from_errno("strdup");
goto done;
}
/* We can't validate the ref itself here. The main process will. */
err = got_pathlist_append(symrefs, name, target);
done:
if (err) {
free(name);
free(target);
}
return err;
}
static const struct got_error *
match_capabilities(char **my_capabilities, struct got_pathlist_head *symrefs,
char *server_capabilities)
{
const struct got_error *err = NULL;
char *capa, *equalsign;
int i;
*my_capabilities = NULL;
do {
capa = strsep(&server_capabilities, " ");
if (capa == NULL)
return NULL;
equalsign = strchr(capa, '=');
if (equalsign != NULL &&
strncmp(capa, "symref", equalsign - capa) == 0) {
err = add_symref(symrefs, equalsign + 1);
if (err)
break;
continue;
}
for (i = 0; i < nitems(got_capabilities); i++) {
err = match_capability(my_capabilities,
capa, &got_capabilities[i]);
if (err)
break;
}
} while (capa);
return err;
}
static const struct got_error *
fetch_pack(int fd, int packfd, struct got_object_id *packid,
struct imsgbuf *ibuf)
{
const struct got_error *err = NULL;
char buf[GOT_PKTMAX], *sp[3];
char hashstr[SHA1_DIGEST_STRING_LENGTH];
struct got_object_id *have, *want;
int is_firstpkt = 1, nref = 0, refsz = 16;
int i, n, req;
off_t packsz;
char *my_capabilities = NULL;
struct got_pathlist_head symrefs;
struct got_pathlist_entry *pe;
TAILQ_INIT(&symrefs);
have = malloc(refsz * sizeof(have[0]));
if (have == NULL)
return got_error_from_errno("malloc");
want = malloc(refsz * sizeof(want[0]));
if (want == NULL) {
err = got_error_from_errno("malloc");
goto done;
}
if (chattygit)
fprintf(stderr, "starting fetch\n");
while (1) {
n = readpkt(fd, buf, sizeof(buf));
if (n == -1){
err = got_error_from_errno("readpkt");
goto done;
}
if (n == 0)
break;
if (n >= 4 && strncmp(buf, "ERR ", 4) == 0) {
static char msg[1024];
for (i = 0; i < n && i < sizeof(msg) - 1; i++) {
if (!isprint(buf[i])) {
err = got_error(GOT_ERR_FETCH_FAILED);
goto done;
}
msg[i] = buf[i];
}
msg[i] = '\0';
err = got_error_msg(GOT_ERR_FETCH_FAILED, msg);
goto done;
}
err = got_tokenize_refline(sp, buf, n);
if (err)
goto done;
if (chattygit && sp[2][0] != '\0')
fprintf(stderr, "server capabilities: %s\n", sp[2]);
if (is_firstpkt) {
err = match_capabilities(&my_capabilities, &symrefs,
sp[2]);
if (err)
goto done;
if (chattygit && my_capabilities)
fprintf(stderr, "my matched capabilities: %s\n",
my_capabilities);
err = got_privsep_send_fetch_symrefs(ibuf, &symrefs);
if (err)
goto done;
}
is_firstpkt = 0;
if (strstr(sp[1], "^{}"))
continue;
if (fetchbranch && !got_match_branch(sp[1], fetchbranch))
continue;
if (refsz == nref + 1){
refsz *= 2;
have = realloc(have, refsz * sizeof(have[0]));
if (have == NULL) {
err = got_error_from_errno("realloc");
goto done;
}
want = realloc(want, refsz * sizeof(want[0]));
if (want == NULL) {
err = got_error_from_errno("realloc");
goto done;
}
}
if (!got_parse_sha1_digest(want[nref].sha1, sp[0])) {
err = got_error(GOT_ERR_BAD_OBJ_ID_STR);
goto done;
}
if (got_resolve_remote_ref(&have[nref], sp[1]) == -1)
memset(&have[nref], 0, sizeof(have[nref]));
err = got_privsep_send_fetch_progress(ibuf, &want[nref], sp[1]);
if (err)
goto done;
if (chattygit)
fprintf(stderr, "remote %s\n", sp[1]);
nref++;
}
req = 0;
for (i = 0; i < nref; i++){
if (got_object_id_cmp(&have[i], &want[i]) == 0)
continue;
if (got_has_object(&want[i]))
continue;
got_sha1_digest_to_str(want[i].sha1, hashstr, sizeof(hashstr));
n = snprintf(buf, sizeof(buf), "want %s%s%s\n", hashstr,
i == 0 && my_capabilities ? " " : "",
i == 0 && my_capabilities ? my_capabilities : "");
if (n >= sizeof(buf)) {
err = got_error(GOT_ERR_NO_SPACE);
goto done;
}
if (writepkt(fd, buf, n) == -1) {
err = got_error_from_errno("writepkt");
goto done;
}
req = 1;
}
flushpkt(fd);
for (i = 0; i < nref; i++){
if (got_object_id_cmp(&have[i], &zhash) == 0)
continue;
got_sha1_digest_to_str(want[i].sha1, hashstr, sizeof(hashstr));
n = snprintf(buf, sizeof(buf), "have %s\n", hashstr);
if (n >= sizeof(buf)) {
err = got_error(GOT_ERR_NO_SPACE);
goto done;
}
if (writepkt(fd, buf, n + 1) == -1) {
err = got_error_from_errno("writepkt");
goto done;
}
}
if (!req){
fprintf(stderr, "up to date\n");
flushpkt(fd);
}
n = snprintf(buf, sizeof(buf), "done\n");
if (writepkt(fd, buf, n) == -1) {
err = got_error_from_errno("writepkt");
goto done;
}
if (!req)
return 0;
if ((n = readpkt(fd, buf, sizeof(buf))) == -1) {
err = got_error_from_errno("readpkt");
goto done;
}
buf[n] = 0;
if (chattygit)
fprintf(stderr, "fetching...\n");
packsz = 0;
while (1) {
ssize_t w;
n = readn(fd, buf, sizeof buf);
if (n == 0)
break;
if (n == -1) {
err = got_error_from_errno("readn");
goto done;
}
w = write(packfd, buf, n);
if (w == -1) {
err = got_error_from_errno("write");
goto done;
}
if (w != n) {
err = got_error(GOT_ERR_IO);
goto done;
}
packsz += n;
}
if (lseek(packfd, 0, SEEK_SET) == -1) {
err = got_error_from_errno("lseek");
goto done;
}
if (got_check_pack_hash(packfd, packsz, packid->sha1) == -1)
err = got_error(GOT_ERR_BAD_PACKFILE);
done:
TAILQ_FOREACH(pe, &symrefs, entry) {
free((void *)pe->path);
free(pe->data);
}
got_pathlist_free(&symrefs);
free(have);
free(want);
return err;
}
int
main(int argc, char **argv)
{
const struct got_error *err = NULL;
int fetchfd, packfd = -1;
struct got_object_id packid;
struct imsgbuf ibuf;
struct imsg imsg;
if(getenv("GOT_DEBUG") != NULL){
fprintf(stderr, "fetch-pack being chatty!\n");
chattygit = 1;
}
imsg_init(&ibuf, GOT_IMSG_FD_CHILD);
if((err = got_privsep_recv_imsg(&imsg, &ibuf, 0)) != 0) {
if (err->code == GOT_ERR_PRIVSEP_PIPE)
err = NULL;
goto done;
}
if (imsg.hdr.type == GOT_IMSG_STOP)
goto done;
if (imsg.hdr.type != GOT_IMSG_FETCH_REQUEST) {
err = got_error(GOT_ERR_PRIVSEP_MSG);
goto done;
}
if (imsg.hdr.len - IMSG_HEADER_SIZE != 0) {
err = got_error(GOT_ERR_PRIVSEP_LEN);
goto done;
}
fetchfd = imsg.fd;
if((err = got_privsep_recv_imsg(&imsg, &ibuf, 0)) != 0) {
if (err->code == GOT_ERR_PRIVSEP_PIPE)
err = NULL;
goto done;
}
if (imsg.hdr.type == GOT_IMSG_STOP)
goto done;
if (imsg.hdr.type != GOT_IMSG_TMPFD) {
err = got_error(GOT_ERR_PRIVSEP_MSG);
goto done;
}
if (imsg.hdr.len - IMSG_HEADER_SIZE != 0) {
err = got_error(GOT_ERR_PRIVSEP_LEN);
goto done;
}
packfd = imsg.fd;
err = fetch_pack(fetchfd, packfd, &packid, &ibuf);
if (err)
goto done;
done:
if (packfd != -1 && close(packfd) == -1 && err == NULL)
err = got_error_from_errno("close");
if (err != NULL)
got_privsep_send_error(&ibuf, err);
else
err = got_privsep_send_fetch_done(&ibuf, packid);
if(err != NULL) {
fprintf(stderr, "%s: %s\n", getprogname(), err->msg);
got_privsep_send_error(&ibuf, err);
}
exit(0);
}
