diff options
Diffstat (limited to 'src/tipideed/cgi.c')
| -rw-r--r-- | src/tipideed/cgi.c | 381 |
1 files changed, 381 insertions, 0 deletions
diff --git a/src/tipideed/cgi.c b/src/tipideed/cgi.c new file mode 100644 index 0000000..7a3ca03 --- /dev/null +++ b/src/tipideed/cgi.c @@ -0,0 +1,381 @@ +/* ISC license. */ + +#include <unistd.h> +#include <string.h> +#include <strings.h> +#include <errno.h> +#include <signal.h> + +#include <skalibs/gccattributes.h> +#include <skalibs/posixplz.h> +#include <skalibs/types.h> +#include <skalibs/bytestr.h> +#include <skalibs/buffer.h> +#include <skalibs/error.h> +#include <skalibs/allreadwrite.h> +#include <skalibs/strerr.h> +#include <skalibs/stralloc.h> +#include <skalibs/djbunix.h> +#include <skalibs/iopause.h> +#include <skalibs/env.h> +#include <skalibs/exec.h> +#include <skalibs/unix-timed.h> +#include <skalibs/lolstdio.h> + +#include <tipidee/method.h> +#include <tipidee/headers.h> +#include <tipidee/response.h> +#include <tipidee/uri.h> +#include "tipideed-internal.h" + +static void addenv_ (tipidee_rql const *rql, char const *k, char const *v, int slash) +{ + if (!stralloc_cats(&g.sa, k) + || !stralloc_catb(&g.sa, "=/", 1 + !!slash) + || !stralloc_cats(&g.sa, v) + || !stralloc_0(&g.sa)) + die500sys(rql, 111, "stralloc_catb") ; +} + +#define addenv(rql, k, v) addenv_(rql, k, (v), 0) +#define addenvslash(rql, k, v) addenv_(rql, k, (v), 1) + +static void delenv (tipidee_rql const *rql, char const *k) +{ + if (!stralloc_cats(&g.sa, k) + || !stralloc_0(&g.sa)) + die500sys(rql, 111, "stralloc_catb") ; +} + +static inline void modify_env (tipidee_rql const *rql, tipidee_headers const *hdr, size_t cl, char const *script, char const *infopath) +{ + uint32_t got = 0 ; + addenv(rql, "REQUEST_METHOD", tipidee_method_tostr(rql->m)) ; + if (cl) + { + char fmt[SIZE_FMT] ; + fmt[size_fmt(fmt, cl)] = 0 ; + addenv(rql, "CONTENT_LENGTH", fmt) ; + } + else delenv(rql, "CONTENT_LENGTH") ; + + if (infopath) addenvslash(rql, "PATH_INFO", infopath) ; + else delenv(rql, "PATH_INFO") ; + if (rql->uri.query) addenv(rql, "QUERY_STRING", rql->uri.query) ; + else delenv(rql, "QUERY_STRING") ; + addenv(rql, "SCRIPT_NAME", script) ; + + for (size_t i = 0 ; i < hdr->n ; i++) + { + char const *key = hdr->buf + hdr->list[i].left ; + char const *val = hdr->buf + hdr->list[i].right ; + if (!strcasecmp(key, "Authorization")) + { + size_t n = str_chr(val, ' ') ; + if (n) + { + char scheme[n] ; + memcpy(scheme, val, n-1) ; + scheme[n-1] = 0 ; + addenv(rql, "AUTH_TYPE", scheme) ; + got |= 1 ; + } + } + else if (!strcasecmp(key, "Content-Type")) { addenv(rql, "CONTENT_TYPE", val) ; got |= 2 ; } + else if (!strcasecmp(key, "Content-Length") || !strcasecmp(key, "Connection")) ; + else + { + size_t len = strlen(key), pos = g.sa.len + 5 ; + if (!stralloc_catb(&g.sa, "HTTP_", 5)) die500sys(rql, 111, "stralloc_catb") ; + addenv(rql, key, val) ; + for (char *s = g.sa.s + pos ; len-- ; s++) + if (*s == '-') *s = '_' ; + else if (*s >= 'a' && *s <= 'z') *s -= 32 ; + } + } + if (!(got & 1)) delenv(rql, "AUTH_TYPE") ; + if (!(got & 2)) delenv(rql, "CONTENT_TYPE") ; +} + +static inline int do_nph (tipidee_rql const *rql, char const *const *argv, char const *const *envp, char const *body, size_t bodylen) gccattr_noreturn ; +static inline int do_nph (tipidee_rql const *rql, char const *const *argv, char const *const *envp, char const *body, size_t bodylen) +{ + int p[2] ; + log_nph(argv, envp) ; + if (pipe(p) == -1) die500sys(rql, 111, "pipe") ; + if (bodylen) + { + switch (fork()) + { + case -1 : die500sys(rql, 111, "fork") ; + case 0 : + { + tain deadline ; + char buf[4096] ; + buffer b = BUFFER_INIT(&buffer_write, p[1], buf, 4096) ; + PROG = "tipidee (nph helper child)" ; + tain_add_g(&deadline, &g.cgitto) ; + close(p[0]) ; + if (ndelay_on(p[1]) == -1) strerr_diefu1sys(111, "set fd nonblocking") ; + if (buffer_timed_put_g(&b, body, bodylen, &deadline) < bodylen + || !buffer_timed_flush_g(&b, &deadline)) + strerr_diefu2sys(111, "write request body to nph ", argv[0]) ; + _exit(0) ; + } + default : break ; + } + } + close(p[1]) ; + if (fd_move(0, p[0]) == -1) die500sys(rql, 111, "fd_move") ; + exec_e(argv, envp) ; + die500sys(rql, errno == ENOENT ? 127 : 126, "exec nph ", argv[0]) ; +} + +static inline int run_cgi (tipidee_rql const *rql, char const *const *argv, char const *const *envp, char const *body, size_t bodylen, tipidee_headers *hdr, stralloc *sa) +{ + iopause_fd x[2] = { { .events = IOPAUSE_READ }, { .events = IOPAUSE_WRITE } } ; + size_t bodyw = 0 ; + unsigned int rstate = 0 ; + tain deadline ; + pid_t pid ; + disize curheader = DISIZE_ZERO ; + uint32_t parserstate = 0 ; + buffer b ; + char buf[4096] ; + log_cgi(argv, envp) ; + { + int fd[2] = { 0, 1 } ; + pid = child_spawn2(argv[0], argv, envp, fd) ; + if (!pid) die500sys(rql, 111, "spawn ", argv[0]) ; + x[0].fd = fd[0] ; x[1].fd = fd[1] ; + } + if (!bodylen) + { + close(x[1].fd) ; + x[1].fd = -1 ; + LOLDEBUG("run_cgi: no request body, closing writing pipe to cgi") ; + } + buffer_init(&b, &buffer_read, x[0].fd, buf, 4096) ; + tain_add_g(&deadline, &g.cgitto) ; + while (x[0].fd >= 0) + { + int r = iopause_g(x, 1 + (x[1].fd >= 0), &deadline) ; + if (r == -1) die500sys(rql, 111, "iopause") ; + if (!r) + { + kill(pid, SIGTERM) ; + respond_504(rql) ; + break ; + } + if (x[1].fd >= 0 && x[1].revents & (IOPAUSE_WRITE | IOPAUSE_EXCEPT)) + { + size_t len = allwrite(x[1].fd, body + bodyw, bodylen - bodyw) ; + if (!len) + { + if (g.verbosity) strerr_warnwu2sys("write request body to cgi ", argv[0]) ; + bodyw = bodylen ; + } + else bodyw += len ; + if (bodyw >= bodylen) + { + close(x[1].fd) ; + x[1].fd = -1 ; + LOLDEBUG("run_cgi: finished writing body") ; + } + } + if (x[0].fd >= 0 && x[0].revents & (IOPAUSE_READ | IOPAUSE_EXCEPT)) + { + switch (rstate) + { + case 0 : + { + r = tipidee_headers_parse_nb(&b, hdr, &curheader, &parserstate) ; + switch (r) + { + case -2 : break ; + case -1 : die500sys(rql, 111, "read from cgi ", argv[0]) ; + case 0 : + { + size_t n = buffer_len(&b) ; + if (!stralloc_readyplus(sa, n)) die500sys(rql, 111, "stralloc_readyplus") ; + buffer_getnofill(&b, sa->s + sa->len, n) ; + sa->len += n ; + rstate = 1 ; + break ; + } + case 400 : die502x(rql, 1, "invalid headers", " from cgi ", argv[0]) ; + case 413 : die502x(rql, 1, hdr->n >= TIPIDEE_HEADERS_MAX ? "Too many headers" : "Too much header data", " from cgi ", argv[0]) ; + case 500 : die500x(rql, 101, "can't happen: ", "avltreen_insert failed", " in do_cgi") ; + default : die500x(rql, 101, "can't happen: ", "unknown tipidee_headers_parse return code", " in do_cgi") ; + } + if (!rstate) break ; + } + case 1 : + { + if (!slurpn(x[0].fd, sa, g.maxcgibody)) + { + if (error_isagain(errno)) break ; + else if (errno == ENOBUFS) die502x(rql, 1, "Too fat body", " from cgi ", argv[0]) ; + else die500sys(rql, 111, "read body", " from cgi ", argv[0]) ; + } + close(x[0].fd) ; + x[0].fd = -1 ; + rstate = 2 ; + LOLDEBUG("run_cgi: rstate = 2") ; + } + } + } + } + if (x[1].fd >= 0) close(x[1].fd) ; + if (x[0].fd >= 0) close(x[0].fd) ; + return rstate == 2 ; +} + +static inline int local_redirect (tipidee_rql *rql, char const *loc, char *uribuf, char const *cginame) +{ + size_t n ; + size_t hostlen = strlen(rql->uri.host) ; + uint16_t port = rql->uri.port ; + uint8_t ishttps = rql->uri.https ; + char hosttmp[hostlen + 1] ; + memcpy(hosttmp, rql->uri.host, hostlen + 1) ; + n = tipidee_uri_parse(uribuf, URI_BUFSIZE, loc, &rql->uri) ; + if (!n || n + hostlen + 1 > URI_BUFSIZE) + die502x(rql, 1, "cgi ", cginame, " returned an invalid ", "Location", " value", " for local redirection") ; + memcpy(uribuf + n, hosttmp, hostlen + 1) ; + rql->uri.host = uribuf + n ; + rql->uri.port = port ; + rql->uri.https = ishttps ; + return 1 ; +} + +static inline void print_cgi_headers (tipidee_headers const *hdr, size_t rbodylen) +{ + static char const *const nope_table[] = + { + "Connection", + "Date", + "Status", + "Content-Length", + 0 + } ; + for (size_t i = 0 ; i < hdr->n ; i++) + { + char const *key = hdr->buf + hdr->list[i].left ; + char const *const *p = nope_table ; + if (tipidee_response_header_builtin_search(key)) continue ; + if (str_start(key, "X-CGI-")) continue ; + for (; *p ; p++) if (!strcasecmp(key, *p)) break ; + if (*p) continue ; + buffer_putsnoflush(buffer_1, key) ; + buffer_putnoflush(buffer_1, ": ", 2) ; + buffer_putsnoflush(buffer_1, hdr->buf + hdr->list[i].right) ; + buffer_putnoflush(buffer_1, "\r\n", 2) ; + } + if (rbodylen) + { + char fmt[SIZE_FMT] ; + fmt[size_fmt(fmt, rbodylen)] = 0 ; + buffer_putsnoflush(buffer_1, "Content-Length: ") ; + buffer_putsnoflush(buffer_1, fmt) ; + buffer_putnoflush(buffer_1, "\r\n", 2) ; + } +} + +static inline int process_cgi_output (tipidee_rql *rql, tipidee_headers const *hdr, char const *rbody, size_t rbodylen, char *uribuf, char const *cginame) +{ + char const *location = tipidee_headers_search(hdr, "Location") ; + char const *x = tipidee_headers_search(hdr, "Status") ; + char const *reason_phrase = "OK" ; + unsigned int status = 0 ; + tain deadline ; + tain_add_g(&deadline, &g.writetto) ; + if (x) + { + size_t m = uint_scan(x, &status) ; + if (!m || x[m] != ' ') + die502x(rql, 1, "cgi ", cginame, " returned an invalid ", "Status", " header") ; + reason_phrase = x + m + 1 ; + if (status >= 300 && status < 399 && !location) + die502x(rql, 1, "cgi ", cginame, " returned a 3xx status code without a ", "Location", " header") ; + if (status < 100 || status > 999) + die502x(rql, 1, "cgi ", cginame, " returned an invalid ", "Status", " value") ; + } + if (location) + { + if (!location[0]) die502x(rql, 1, "cgi ", cginame, " returned an invalid ", "Location", " header") ; + if (location[0] == '/' && location[1] != '/') return local_redirect(rql, location, uribuf, cginame) ; + if (rbodylen) + { + if (!status) + die502x(rql, 1, "cgi ", cginame, " didn't output a ", "Status", " header", " for a client redirect response with document") ; + if (status < 300 || status > 399) + die502x(rql, 1, "cgi ", cginame, " returned an invalid ", "Status", " value", " for a client redirect response with document") ; + } + else + { + for (size_t i = 0 ; i < hdr->n ; i++) + { + char const *key = hdr->buf + hdr->list[i].left ; + if (!strcasecmp(key, "Location")) continue ; + if (str_start(key, "X-CGI-")) continue ; + die502x(rql, 1, "cgi ", cginame, "returned extra headers", " for a client redirect response without document") ; + } + status = 302 ; + reason_phrase = "Found" ; + } + } + else + { + if (!status) status = 200 ; + if (!tipidee_headers_search(hdr, "Content-Type")) + die502x(rql, 1, "cgi ", cginame, " didn't output a ", "Content-Type", " header") ; + } + x = tipidee_headers_search(hdr, "Content-Length") ; + if (x) + { + size_t cln ; + if (!size0_scan(x, &cln)) + die502x(rql, 1, "cgi ", cginame, " returned an invalid ", "Content-Length", " header") ; + if (cln != rbodylen) + die502x(rql, 1, "cgi ", cginame, " returned a mismatching ", "Content-Length", " header") ; + } + + tipidee_response_status(buffer_1, rql, status, reason_phrase) ; + tipidee_response_header_common_put_g(buffer_1, !g.cont) ; + print_cgi_headers(hdr, rbodylen) ; + if (buffer_timed_put_g(buffer_1, "\r\n", 2, &deadline) < 2) + strerr_diefu1sys(111, "write to stdout") ; + if (rbodylen) + { + if (buffer_timed_put_g(buffer_1, rbody, rbodylen, &deadline) < rbodylen) + strerr_diefu1sys(111, "write to stdout") ; + } + if (!buffer_timed_flush_g(buffer_1, &deadline)) + strerr_diefu1sys(111, "write to stdout") ; + return 0 ; +} + +static inline int do_cgi (tipidee_rql *rql, char const *const *argv, char const *const *envp, char const *body, size_t bodylen, char *uribuf) +{ + static stralloc sa = STRALLOC_ZERO ; + tipidee_headers hdr ; + char hdrbuf[2048] ; + sa.len = 0 ; + tipidee_headers_init(&hdr, hdrbuf, 2048) ; + if (!run_cgi(rql, argv, envp, body, bodylen, &hdr, &sa)) return 0 ; + return process_cgi_output(rql, &hdr, sa.s, sa.len, uribuf, argv[0]) ; +} + +int respond_cgi (tipidee_rql *rql, char const *fn, size_t docrootlen, char const *infopath, char *uribuf, tipidee_headers const *hdr, tipidee_resattr const *ra, char const *body, size_t bodylen) +{ + size_t sabase = g.sa.len ; + size_t envmax = g.envlen + 16 + TIPIDEE_HEADERS_MAX ; + char const *argv[2] = { fn, 0 } ; + char const *envp[envmax] ; + modify_env(rql, hdr, bodylen, fn + docrootlen, infopath) ; + env_merge(envp, envmax, (char const *const *)environ, g.envlen, g.sa.s + g.cwdlen + 1, g.sa.len - (g.cwdlen+1)) ; + g.sa.len = sabase ; + return ra->isnph ? do_nph(rql, argv, envp, body, bodylen) : + do_cgi(rql, argv, envp, body, bodylen, uribuf) ; +} |