c-ipfs/core/api.c

583 lines
14 KiB
C

/**
* Methods for lightweight/specific HTTP for API communication.
*/
#define _GNU_SOURCE
#define __USE_GNU
#include <pthread.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <stdio.h>
#include <arpa/inet.h>
#include <fcntl.h>
#include "libp2p/net/p2pnet.h"
#include "libp2p/utils/logger.h"
#include "ipfs/core/api.h"
pthread_mutex_t conns_lock;
int conns_count;
pthread_t listen_thread = 0;
struct s_list api_list;
/**
* Write two strings on one write.
* @param fd file descriptor to write.
* @param str1 first string to write.
* @param str2 second string to write.
*/
size_t write_dual(int fd, char *str1, char *str2)
{
struct iovec iov[2];
iov[0].iov_base = str1;
iov[0].iov_len = strlen(str1);
iov[1].iov_base = str2;
iov[1].iov_len = strlen(str2);
return writev(fd, iov, 2);
}
int find_chunk(char *buf, const size_t buf_size, size_t *pos, size_t *size)
{
char *p = NULL;
*size = strtol(buf, &p, 16);
if (*size < 0 || !p || p < buf || p > (buf + 10)) {
return 0;
}
*pos = (int)(p - buf);
if (p[0] == '\r' && p[1] == '\n') {
*pos += 2;
return 1;
}
return 0;
}
int read_chunked(int fd, struct s_request *req, char *already, size_t already_size)
{
char buf[MAX_READ], *p;
size_t pos, nsize, buf_size = 0, r;
if (already_size > 0) {
if (already_size <= sizeof(buf)) {
memcpy(buf, already, already_size);
buf_size += already_size;
already_size = 0;
} else {
memcpy(buf, already, sizeof(buf));
already += sizeof(buf);
buf_size += sizeof(buf);
already_size -= sizeof(buf);
}
}
while(buf_size) {
if (!find_chunk(buf, buf_size, &pos, &nsize)) {
libp2p_logger_error("api", "fail find_chunk.\n");
libp2p_logger_error("api", "nsize = %d.\n", nsize);
return 0;
}
if (nsize == 0) {
break;
}
p = realloc(req->buf, req->size + nsize);
if (!p) {
libp2p_logger_error("api", "fail realloc.\n");
return 0;
}
req->buf = p;
req->size += nsize;
CPCHUNK:
r = nsize;
buf_size -= pos;
if (r > buf_size) {
r = buf_size;
}
memcpy(req->buf + req->body + req->body_size, buf + pos, r);
req->body_size += r;
nsize -= r;
buf_size -= r;
if (buf_size > 0) {
memmove(buf, buf + pos + r, buf_size);
}
pos = 0;
if (already_size > 0) {
r = sizeof(buf) - buf_size;
if (already_size <= r) {
memcpy(buf, already, already_size);
buf_size += already_size;
already_size = 0;
} else {
memcpy(buf, already, r);
already += r;
buf_size += r;
already_size -= r;
}
}
if (socket_read_select4(fd, 5) > 0) {
r = sizeof(buf) - buf_size;
r = read(fd, buf+buf_size, r);
buf_size += r;
if (r == 0 && nsize == 0) {
break;
}
if (r <= 0) {
libp2p_logger_error("api", "read fail.\n");
return 0;
}
}
if (nsize > 0)
goto CPCHUNK; // still have data to transfer on current chunk.
if (memcmp (buf, "\r\n", 2)!=0) {
libp2p_logger_error("api", "fail CRLF.\n");
return 0;
}
}
return 1;
}
int read_all(int fd, struct s_request *req, char *already, size_t alread_size)
{
char buf[MAX_READ], *p;
size_t size = 0;
if (alread_size > 0) {
p = realloc(req->buf, req->size + alread_size);
if (!p) {
return 0;
}
req->buf = p;
req->size += alread_size;
memcpy(req->buf + req->body + req->body_size, already, alread_size);
req->body_size += alread_size;
}
for(;;) {
if (socket_read_select4(fd, 5) <= 0) {
break;
}
size = read(fd, buf, sizeof buf);
if (size <= 0) {
break;
}
p = realloc(req->buf, req->size + size);
if (!p) {
return 0;
}
req->buf = p;
req->size += size;
memcpy(req->buf + req->body + req->body_size, buf, size);
req->body_size += size;
}
return 1;
}
/**
* Find a token in a string array.
* @param string array and token string.
* @returns the pointer after where the token was found or NULL if it fails.
*/
char *str_tok(char *str, char *tok)
{
char *p = strstr(str, tok);
if (p) {
p += strlen(tok);
while(*p == ' ') p++;
}
return p;
}
/**
* Find a token in a binary array.
* @param array, size of array, token and size of token.
* @returns the pointer after where the token was found or NULL if it fails.
*/
char *bin_tok(char *bin, size_t limit, char *tok, size_t tok_size)
{
char *p = memmem(bin, limit, tok, tok_size);
if (p) {
p += tok_size;
}
return p;
}
/**
* Check if header contain a especific value.
* @param request structure, header name and value to check.
* @returns the pointer where the value was found or NULL if it fails.
*/
char *header_value_cmp(struct s_request *req, char *header, char *value)
{
char *p = str_tok(req->buf + req->header, header);
if (p) {
if (strstart(p, value)) {
return p;
}
}
return NULL;
}
/**
* Lookup for boundary at buffer string.
* @param body buffer string, boundary id, filename and content-type string.
* @returns the pointer where the multipart start.
*/
char *boundary_find(char *str, char *boundary, char **filename, char **contenttype)
{
char *p = str_tok(str, "--");
while (p) {
if (strstart(p, boundary)) {
// skip to the beginning, ignoring the header for now, if there is.
// TODO: return filename and content-type
p = strstr(p, "\r\n\r\n");
if (p) {
return p + 4; // ignore 4 bytes CRLF 2x
}
break;
}
p = str_tok(str, "--");
}
return NULL;
}
/**
* Return the size of boundary.
* @param boundary buffer, boundary id.
* @returns the size of boundary or 0 if fails.
*/
size_t boundary_size(char *str, char *boundary, size_t limit)
{
char *p = bin_tok(str, limit, "\r\n--", 4);
while (p) {
if (strstart(p, boundary)) {
if (cstrstart(p + strlen(boundary), "--\r\n")) {
p -= 4;
return (size_t)(p - str);
}
}
p = bin_tok(p, limit, "\r\n--", 4);
}
return 0;
}
/**
* Pthread to take care of each client connection.
* @param ptr is the connection index in api_list, integer not pointer, cast required.
* @returns nothing
*/
void *api_connection_thread (void *ptr)
{
int timeout, s, r;
const INT_TYPE i = (INT_TYPE) ptr;
char resp[MAX_READ+1], buf[MAX_READ+1], *p, *body;
char client[INET_ADDRSTRLEN];
struct s_request req;
int (*read_func)(int, struct s_request*, char*, size_t) = read_all;
req.buf = NULL; // sanity.
buf[MAX_READ] = '\0';
s = api_list.conns[i]->socket;
timeout = api_list.timeout;
if (socket_read_select4(s, timeout) <= 0) {
libp2p_logger_error("api", "Client connection timeout.\n");
goto quit;
}
r = read(s, buf, sizeof buf);
if (r <= 0) {
libp2p_logger_error("api", "Read from client fail.\n");
goto quit;
}
buf[r] = '\0';
p = strstr(buf, "\r\n\r\n");
if (p) {
body = p + 4;
req.size = p - buf + 1;
req.buf = malloc(req.size);
if (!req.buf) {
// memory allocation fail.
libp2p_logger_error("api", "malloc fail.\n");
write_cstr (s, HTTP_500);
goto quit;
}
memcpy(req.buf, buf, req.size - 1);
req.buf[req.size-1] = '\0';
req.method = 0;
p = strchr(req.buf + req.method, ' ');
if (!p) {
libp2p_logger_error("api", "fail looking for space on method '%s'.\n", req.buf + req.method);
write_cstr (s, HTTP_400);
goto quit;
}
*p++ = '\0'; // End of method.
req.path = p - req.buf;
p = strchr(p, ' ');
if (!p) {
libp2p_logger_error("api", "fail looking for space on path '%s'.\n", req.buf + req.path);
write_cstr (s, HTTP_400);
goto quit;
}
*p++ = '\0'; // End of path.
req.http_ver = p - req.buf;
p = strchr(req.buf + req.http_ver, '\r');
if (!p) {
libp2p_logger_error("api", "fail looking for CR on http_ver '%s'.\n", req.buf + req.http_ver);
write_cstr (s, HTTP_400);
goto quit;
}
*p++ = '\0'; // End of http version.
while (*p == '\r' || *p == '\n') p++;
req.header = p - req.buf;
req.body = req.size;
req.body_size = 0;
if (header_value_cmp(&req, "Transfer-Encoding:", "chunked")) {
read_func = read_chunked;
}
if (!read_func(s, &req, body, r - (body - buf))) {
libp2p_logger_error("api", "fail read_func.\n");
write_cstr (s, HTTP_500);
goto quit;
}
if (strcmp(req.buf + req.method, "GET")==0) {
// just an error message, because it's not used yet.
// TODO: implement gateway requests and GUI (javascript) for API.
write_dual (s, req.buf + req.http_ver, strchr (HTTP_404, ' '));
} else if (cstrstart(buf, "POST ")) {
// TODO: Handle gzip/json POST requests.
p = header_value_cmp(&req, "Content-Type:", "multipart/form-data;");
if (p) {
p = str_tok(p, "boundary=");
if (p) {
char *boundary, *l;
int len;
if (*p == '"') {
p++;
l = strchr(p, '"');
} else {
l = p;
while (*l != '\r' && *l != '\0') l++;
}
len = l - p;
boundary = malloc (len+1);
if (boundary) {
memcpy(boundary, p, len);
boundary[len] = '\0';
p = boundary_find(req.buf + req.body, boundary, NULL, NULL);
if (p) {
req.boundary_size = boundary_size(p, boundary, req.size - (p - buf));
if (req.boundary_size > 0) {
req.boundary = p - req.buf;
}
}
free (boundary);
}
}
}
// TODO: Parse the path var and decide what to do with the received data.
if (req.boundary > 0) {
libp2p_logger_error("api", "boundary index = %d, size = %d\n", req.boundary, req.boundary_size);
}
libp2p_logger_error("api", "method = '%s'\n"
"path = '%s'\n"
"http_ver = '%s'\n"
"header {\n%s\n}\n"
"body_size = %d\n",
req.buf+req.method, req.buf+req.path, req.buf+req.http_ver,
req.buf+req.header, req.body_size);
snprintf(resp, sizeof(resp), "%s 200 OK\r\n" \
"Content-Type: application/json\r\n"
"Server: c-ipfs/0.0.0-dev\r\n"
"X-Chunked-Output: 1\r\n"
"Connection: close\r\n"
"Transfer-Encoding: chunked\r\n\r\n", req.buf + req.http_ver);
write_str (s, resp);
libp2p_logger_error("api", "resp = {\n%s\n}\n", resp);
}
} else {
libp2p_logger_error("api", "fail looking for body.\n");
write_cstr (s, HTTP_400);
}
quit:
if (req.buf)
free(req.buf);
if (inet_ntop(AF_INET, &(api_list.conns[i]->ipv4), client, INET_ADDRSTRLEN) == NULL)
strcpy(client, "UNKNOW");
libp2p_logger_error("api", "Closing client connection %s:%d (%d).\n", client, api_list.conns[i]->port, i+1);
pthread_mutex_lock(&conns_lock);
close(s);
free (api_list.conns[i]);
api_list.conns[i] = NULL;
conns_count--;
pthread_mutex_unlock(&conns_lock);
return NULL;
}
/**
* Close all connections stopping respectives pthreads and free allocated memory.
*/
void api_connections_cleanup (void)
{
int i;
pthread_mutex_lock(&conns_lock);
if (conns_count > 0 && api_list.conns) {
for (i = 0 ; i < api_list.max_conns ; i++) {
if (api_list.conns[i]->pthread) {
pthread_cancel (api_list.conns[i]->pthread);
close (api_list.conns[i]->socket);
free (api_list.conns[i]);
api_list.conns[i] = NULL;
}
}
conns_count = 0;
}
if (api_list.conns) {
free (api_list.conns);
api_list.conns = NULL;
}
pthread_mutex_unlock(&conns_lock);
}
/**
* Pthread to keep in background dealing with client connections.
* @param ptr is not used.
* @returns nothing
*/
void *api_listen_thread (void *ptr)
{
int s;
INT_TYPE i;
uint32_t ipv4;
uint16_t port;
char client[INET_ADDRSTRLEN];
conns_count = 0;
for (;;) {
s = socket_accept4(api_list.socket, &ipv4, &port);
if (s <= 0) {
break;
}
if (conns_count >= api_list.max_conns) { // limit reached.
libp2p_logger_error("api", "Limit of connections reached (%d).\n", api_list.max_conns);
close (s);
continue;
}
pthread_mutex_lock(&conns_lock);
for (i = 0 ; i < api_list.max_conns && api_list.conns[i] ; i++);
api_list.conns[i] = malloc (sizeof (struct s_conns));
if (!api_list.conns[i]) {
libp2p_logger_error("api", "Fail to allocate memory to accept connection.\n");
close (s);
continue;
}
if (inet_ntop(AF_INET, &ipv4, client, INET_ADDRSTRLEN) == NULL)
strcpy(client, "UNKNOW");
api_list.conns[i]->socket = s;
api_list.conns[i]->ipv4 = ipv4;
api_list.conns[i]->port = port;
if (pthread_create(&(api_list.conns[i]->pthread), NULL, api_connection_thread, (void*)i)) {
libp2p_logger_error("api", "Create pthread fail.\n");
free (api_list.conns[i]);
api_list.conns[i] = NULL;
conns_count--;
close(s);
} else {
conns_count++;
}
libp2p_logger_error("api", "Accept connection %s:%d (%d/%d), pthread %d.\n", client, port, conns_count, api_list.max_conns, i+1);
pthread_mutex_unlock(&conns_lock);
}
api_connections_cleanup ();
return NULL;
}
/**
* Start API interface daemon.
* @param port.
* @param max_conns.
* @param timeout time out of client connection.
* @returns 0 when failure or 1 if success.
*/
int api_start (uint16_t port, int max_conns, int timeout)
{
int s;
size_t alloc_size = sizeof(void*) * max_conns;
api_list.ipv4 = hostname_to_ip("127.0.0.1"); // api is listening only on loopback.
api_list.port = port;
if (listen_thread != 0) {
libp2p_logger_error("api", "API already running.\n");
return 0;
}
if ((s = socket_listen(socket_tcp4(), &(api_list.ipv4), &(api_list.port))) <= 0) {
libp2p_logger_error("api", "Failed to init API. port: %d\n", port);
return 0;
}
api_list.socket = s;
api_list.max_conns = max_conns;
api_list.timeout = timeout;
api_list.conns = malloc (alloc_size);
if (!api_list.conns) {
close (s);
libp2p_logger_error("api", "Error allocating memory.\n");
return 0;
}
memset(api_list.conns, 0, alloc_size);
if (pthread_create(&listen_thread, NULL, api_listen_thread, NULL)) {
close (s);
free (api_list.conns);
api_list.conns = NULL;
listen_thread = 0;
libp2p_logger_error("api", "Error creating thread for API.\n");
return 0;
}
return 1;
}
/**
* Stop API.
* @returns 0 when failure or 1 if success.
*/
int api_stop (void)
{
if (!listen_thread) return 0;
pthread_cancel(listen_thread);
api_connections_cleanup ();
listen_thread = 0;
return 1;
}