diff options
Diffstat (limited to 'daemon.c')
-rw-r--r-- | daemon.c | 947 |
1 files changed, 584 insertions, 363 deletions
@@ -3,32 +3,33 @@ #include "exec_cmd.h" #include "run-command.h" #include "strbuf.h" - -#include <syslog.h> +#include "string-list.h" #ifndef HOST_NAME_MAX #define HOST_NAME_MAX 256 #endif -#ifndef NI_MAXSERV -#define NI_MAXSERV 32 +#ifdef NO_INITGROUPS +#define initgroups(x, y) (0) /* nothing */ #endif static int log_syslog; static int verbose; static int reuseaddr; +static int informative_errors; static const char daemon_usage[] = "git daemon [--verbose] [--syslog] [--export-all]\n" -" [--timeout=n] [--init-timeout=n] [--max-connections=n]\n" -" [--strict-paths] [--base-path=path] [--base-path-relaxed]\n" -" [--user-path | --user-path=path]\n" -" [--interpolated-path=path]\n" -" [--reuseaddr] [--detach] [--pid-file=file]\n" -" [--[enable|disable|allow-override|forbid-override]=service]\n" -" [--inetd | [--listen=host_or_ipaddr] [--port=n]\n" -" [--user=user [--group=group]]\n" -" [directory...]"; +" [--timeout=<n>] [--init-timeout=<n>] [--max-connections=<n>]\n" +" [--strict-paths] [--base-path=<path>] [--base-path-relaxed]\n" +" [--user-path | --user-path=<path>]\n" +" [--interpolated-path=<path>]\n" +" [--reuseaddr] [--pid-file=<file>]\n" +" [--(enable|disable|allow-override|forbid-override)=<service>]\n" +" [--access-hook=<path>]\n" +" [--inetd | [--listen=<host_or_ipaddr>] [--port=<n>]\n" +" [--detach] [--user=<user> [--group=<group>]]\n" +" [<directory>...]"; /* List of acceptable pathname prefixes */ static char **ok_paths; @@ -38,13 +39,10 @@ static int strict_paths; static int export_all_trees; /* Take all paths relative to this one if non-NULL */ -static char *base_path; -static char *interpolated_path; +static const char *base_path; +static const char *interpolated_path; static int base_path_relaxed; -/* Flag indicating client sent extra args. */ -static int saw_extended_args; - /* If defined, ~user notation is allowed and the string is inserted * after ~user/. E.g. a request to git://host/~alice/frotz would * go to /home/alice/pub_git/frotz with --user-path=pub_git. @@ -55,10 +53,28 @@ static const char *user_path; static unsigned int timeout; static unsigned int init_timeout; -static char *hostname; -static char *canon_hostname; -static char *ip_address; -static char *tcp_port; +struct hostinfo { + struct strbuf hostname; + struct strbuf canon_hostname; + struct strbuf ip_address; + struct strbuf tcp_port; + unsigned int hostname_lookup_done:1; + unsigned int saw_extended_args:1; +}; + +static void lookup_hostname(struct hostinfo *hi); + +static const char *get_canon_hostname(struct hostinfo *hi) +{ + lookup_hostname(hi); + return hi->canon_hostname.buf; +} + +static const char *get_ip_address(struct hostinfo *hi) +{ + lookup_hostname(hi); + return hi->ip_address.buf; +} static void logreport(int priority, const char *err, va_list params) { @@ -68,15 +84,18 @@ static void logreport(int priority, const char *err, va_list params) syslog(priority, "%s", buf); } else { /* - * Since stderr is set to linebuffered mode, the + * Since stderr is set to buffered mode, the * logging of different processes will not overlap + * unless they overflow the (rather big) buffers. */ fprintf(stderr, "[%"PRIuMAX"] ", (uintmax_t)getpid()); vfprintf(stderr, err, params); fputc('\n', stderr); + fflush(stderr); } } +__attribute__((format (printf, 1, 2))) static void logerror(const char *err, ...) { va_list params; @@ -85,6 +104,7 @@ static void logerror(const char *err, ...) va_end(params); } +__attribute__((format (printf, 1, 2))) static void loginfo(const char *err, ...) { va_list params; @@ -101,63 +121,52 @@ static void NORETURN daemon_die(const char *err, va_list params) exit(1); } -static int avoid_alias(char *p) -{ - int sl, ndot; +struct expand_path_context { + const char *directory; + struct hostinfo *hostinfo; +}; - /* - * This resurrects the belts and suspenders paranoia check by HPA - * done in <435560F7.4080006@zytor.com> thread, now enter_repo() - * does not do getcwd() based path canonicalizations. - * - * sl becomes true immediately after seeing '/' and continues to - * be true as long as dots continue after that without intervening - * non-dot character. - */ - if (!p || (*p != '/' && *p != '~')) - return -1; - sl = 1; ndot = 0; - p++; - - while (1) { - char ch = *p++; - if (sl) { - if (ch == '.') - ndot++; - else if (ch == '/') { - if (ndot < 3) - /* reject //, /./ and /../ */ - return -1; - ndot = 0; - } - else if (ch == 0) { - if (0 < ndot && ndot < 3) - /* reject /.$ and /..$ */ - return -1; - return 0; - } - else - sl = ndot = 0; +static size_t expand_path(struct strbuf *sb, const char *placeholder, void *ctx) +{ + struct expand_path_context *context = ctx; + struct hostinfo *hi = context->hostinfo; + + switch (placeholder[0]) { + case 'H': + strbuf_addbuf(sb, &hi->hostname); + return 1; + case 'C': + if (placeholder[1] == 'H') { + strbuf_addstr(sb, get_canon_hostname(hi)); + return 2; } - else if (ch == 0) - return 0; - else if (ch == '/') { - sl = 1; - ndot = 0; + break; + case 'I': + if (placeholder[1] == 'P') { + strbuf_addstr(sb, get_ip_address(hi)); + return 2; } + break; + case 'P': + strbuf_addbuf(sb, &hi->tcp_port); + return 1; + case 'D': + strbuf_addstr(sb, context->directory); + return 1; } + return 0; } -static char *path_ok(char *directory) +static const char *path_ok(const char *directory, struct hostinfo *hi) { static char rpath[PATH_MAX]; static char interp_path[PATH_MAX]; - char *path; - char *dir; + const char *path; + const char *dir; dir = directory; - if (avoid_alias(dir)) { + if (daemon_avoid_alias(dir)) { logerror("'%s': aliased", dir); return NULL; } @@ -173,7 +182,7 @@ static char *path_ok(char *directory) * "~alice/%s/foo". */ int namlen, restlen = strlen(dir); - char *slash = strchr(dir, '/'); + const char *slash = strchr(dir, '/'); if (!slash) slash = dir + restlen; namlen = slash - dir; @@ -184,17 +193,12 @@ static char *path_ok(char *directory) dir = rpath; } } - else if (interpolated_path && saw_extended_args) { + else if (interpolated_path && hi->saw_extended_args) { struct strbuf expanded_path = STRBUF_INIT; - struct strbuf_expand_dict_entry dict[] = { - { "H", hostname }, - { "CH", canon_hostname }, - { "IP", ip_address }, - { "P", tcp_port }, - { "D", directory }, - { "%", "%" }, - { NULL } - }; + struct expand_path_context context; + + context.directory = directory; + context.hostinfo = hi; if (*dir != '/') { /* Allow only absolute */ @@ -203,7 +207,7 @@ static char *path_ok(char *directory) } strbuf_expand(&expanded_path, interpolated_path, - strbuf_expand_dict_cb, &dict); + expand_path, &context); strlcpy(interp_path, expanded_path.buf, PATH_MAX); strbuf_release(&expanded_path); loginfo("Interpolated dir '%s'", interp_path); @@ -274,36 +278,94 @@ struct daemon_service { int overridable; }; -static struct daemon_service *service_looking_at; -static int service_enabled; +static int daemon_error(const char *dir, const char *msg) +{ + if (!informative_errors) + msg = "access denied or repository not exported"; + packet_write(1, "ERR %s: %s", msg, dir); + return -1; +} -static int git_daemon_config(const char *var, const char *value, void *cb) +static const char *access_hook; + +static int run_access_hook(struct daemon_service *service, const char *dir, + const char *path, struct hostinfo *hi) { - if (!prefixcmp(var, "daemon.") && - !strcmp(var + 7, service_looking_at->config_name)) { - service_enabled = git_config_bool(var, value); + struct child_process child = CHILD_PROCESS_INIT; + struct strbuf buf = STRBUF_INIT; + const char *argv[8]; + const char **arg = argv; + char *eol; + int seen_errors = 0; + + *arg++ = access_hook; + *arg++ = service->name; + *arg++ = path; + *arg++ = hi->hostname.buf; + *arg++ = get_canon_hostname(hi); + *arg++ = get_ip_address(hi); + *arg++ = hi->tcp_port.buf; + *arg = NULL; + + child.use_shell = 1; + child.argv = argv; + child.no_stdin = 1; + child.no_stderr = 1; + child.out = -1; + if (start_command(&child)) { + logerror("daemon access hook '%s' failed to start", + access_hook); + goto error_return; + } + if (strbuf_read(&buf, child.out, 0) < 0) { + logerror("failed to read from pipe to daemon access hook '%s'", + access_hook); + strbuf_reset(&buf); + seen_errors = 1; + } + if (close(child.out) < 0) { + logerror("failed to close pipe to daemon access hook '%s'", + access_hook); + seen_errors = 1; + } + if (finish_command(&child)) + seen_errors = 1; + + if (!seen_errors) { + strbuf_release(&buf); return 0; } - /* we are not interested in parsing any other configuration here */ - return 0; +error_return: + strbuf_ltrim(&buf); + if (!buf.len) + strbuf_addstr(&buf, "service rejected"); + eol = strchr(buf.buf, '\n'); + if (eol) + *eol = '\0'; + errno = EACCES; + daemon_error(dir, buf.buf); + strbuf_release(&buf); + return -1; } -static int run_service(char *dir, struct daemon_service *service) +static int run_service(const char *dir, struct daemon_service *service, + struct hostinfo *hi) { const char *path; int enabled = service->enabled; + struct strbuf var = STRBUF_INIT; loginfo("Request %s for '%s'", service->name, dir); if (!enabled && !service->overridable) { logerror("'%s': service not enabled.", service->name); errno = EACCES; - return -1; + return daemon_error(dir, "service not enabled"); } - if (!(path = path_ok(dir))) - return -1; + if (!(path = path_ok(dir, hi))) + return daemon_error(dir, "no such repository"); /* * Security on the cheap. @@ -319,24 +381,29 @@ static int run_service(char *dir, struct daemon_service *service) if (!export_all_trees && access("git-daemon-export-ok", F_OK)) { logerror("'%s': repository not exported.", path); errno = EACCES; - return -1; + return daemon_error(dir, "repository not exported"); } if (service->overridable) { - service_looking_at = service; - service_enabled = -1; - git_config(git_daemon_config, NULL); - if (0 <= service_enabled) - enabled = service_enabled; + strbuf_addf(&var, "daemon.%s", service->config_name); + git_config_get_bool(var.buf, &enabled); + strbuf_release(&var); } if (!enabled) { logerror("'%s': service not enabled for '%s'", service->name, path); errno = EACCES; - return -1; + return daemon_error(dir, "service not enabled"); } /* + * Optionally, a hook can choose to deny access to the + * repository depending on the phase of the moon. + */ + if (access_hook && run_access_hook(service, dir, path, hi)) + return -1; + + /* * We'll ignore SIGTERM from now on, we have a * good client. */ @@ -368,9 +435,8 @@ static void copy_to_log(int fd) static int run_service_command(const char **argv) { - struct child_process cld; + struct child_process cld = CHILD_PROCESS_INIT; - memset(&cld, 0, sizeof(cld)); cld.argv = argv; cld.git_cmd = 1; cld.err = -1; @@ -389,7 +455,9 @@ static int upload_pack(void) { /* Timeout as string */ char timeout_buf[64]; - const char *argv[] = { "upload-pack", "--strict", timeout_buf, ".", NULL }; + const char *argv[] = { "upload-pack", "--strict", NULL, ".", NULL }; + + argv[2] = timeout_buf; snprintf(timeout_buf, sizeof timeout_buf, "--timeout=%u", timeout); return run_service_command(argv); @@ -437,40 +505,86 @@ static void make_service_overridable(const char *name, int ena) die("No such service %s", name); } -static char *xstrdup_tolower(const char *str) +static void parse_host_and_port(char *hostport, char **host, + char **port) +{ + if (*hostport == '[') { + char *end; + + end = strchr(hostport, ']'); + if (!end) + die("Invalid request ('[' without ']')"); + *end = '\0'; + *host = hostport + 1; + if (!end[1]) + *port = NULL; + else if (end[1] == ':') + *port = end + 2; + else + die("Garbage after end of host part"); + } else { + *host = hostport; + *port = strrchr(hostport, ':'); + if (*port) { + **port = '\0'; + ++*port; + } + } +} + +/* + * Sanitize a string from the client so that it's OK to be inserted into a + * filesystem path. Specifically, we disallow slashes, runs of "..", and + * trailing and leading dots, which means that the client cannot escape + * our base path via ".." traversal. + */ +static void sanitize_client(struct strbuf *out, const char *in) +{ + for (; *in; in++) { + if (*in == '/') + continue; + if (*in == '.' && (!out->len || out->buf[out->len - 1] == '.')) + continue; + strbuf_addch(out, *in); + } + + while (out->len && out->buf[out->len - 1] == '.') + strbuf_setlen(out, out->len - 1); +} + +/* + * Like sanitize_client, but we also perform any canonicalization + * to make life easier on the admin. + */ +static void canonicalize_client(struct strbuf *out, const char *in) { - char *p, *dup = xstrdup(str); - for (p = dup; *p; p++) - *p = tolower(*p); - return dup; + sanitize_client(out, in); + strbuf_tolower(out); } /* * Read the host as supplied by the client connection. */ -static void parse_host_arg(char *extra_args, int buflen) +static void parse_host_arg(struct hostinfo *hi, char *extra_args, int buflen) { char *val; int vallen; char *end = extra_args + buflen; if (extra_args < end && *extra_args) { - saw_extended_args = 1; + hi->saw_extended_args = 1; if (strncasecmp("host=", extra_args, 5) == 0) { val = extra_args + 5; vallen = strlen(val) + 1; if (*val) { /* Split <host>:<port> at colon. */ - char *host = val; - char *port = strrchr(host, ':'); - if (port) { - *port = 0; - port++; - free(tcp_port); - tcp_port = xstrdup(port); - } - free(hostname); - hostname = xstrdup_tolower(host); + char *host; + char *port; + parse_host_and_port(val, &host, &port); + if (port) + sanitize_client(&hi->tcp_port, port); + canonicalize_client(&hi->hostname, host); + hi->hostname_lookup_done = 0; } /* On to the next one */ @@ -479,11 +593,14 @@ static void parse_host_arg(char *extra_args, int buflen) if (extra_args < end && *extra_args) die("Invalid request"); } +} - /* - * Locate canonical hostname and its IP address. - */ - if (hostname) { +/* + * Locate canonical hostname and its IP address. + */ +static void lookup_hostname(struct hostinfo *hi) +{ + if (!hi->hostname_lookup_done && hi->hostname.len) { #ifndef NO_IPV6 struct addrinfo hints; struct addrinfo *ai; @@ -493,18 +610,20 @@ static void parse_host_arg(char *extra_args, int buflen) memset(&hints, 0, sizeof(hints)); hints.ai_flags = AI_CANONNAME; - gai = getaddrinfo(hostname, NULL, &hints, &ai); + gai = getaddrinfo(hi->hostname.buf, NULL, &hints, &ai); if (!gai) { struct sockaddr_in *sin_addr = (void *)ai->ai_addr; inet_ntop(AF_INET, &sin_addr->sin_addr, addrbuf, sizeof(addrbuf)); - free(ip_address); - ip_address = xstrdup(addrbuf); + strbuf_addstr(&hi->ip_address, addrbuf); - free(canon_hostname); - canon_hostname = xstrdup(ai->ai_canonname ? - ai->ai_canonname : ip_address); + if (ai->ai_canonname) + sanitize_client(&hi->canon_hostname, + ai->ai_canonname); + else + strbuf_addbuf(&hi->canon_hostname, + &hi->ip_address); freeaddrinfo(ai); } @@ -514,60 +633,56 @@ static void parse_host_arg(char *extra_args, int buflen) char **ap; static char addrbuf[HOST_NAME_MAX + 1]; - hent = gethostbyname(hostname); - - ap = hent->h_addr_list; - memset(&sa, 0, sizeof sa); - sa.sin_family = hent->h_addrtype; - sa.sin_port = htons(0); - memcpy(&sa.sin_addr, *ap, hent->h_length); + hent = gethostbyname(hi->hostname.buf); + if (hent) { + ap = hent->h_addr_list; + memset(&sa, 0, sizeof sa); + sa.sin_family = hent->h_addrtype; + sa.sin_port = htons(0); + memcpy(&sa.sin_addr, *ap, hent->h_length); - inet_ntop(hent->h_addrtype, &sa.sin_addr, - addrbuf, sizeof(addrbuf)); + inet_ntop(hent->h_addrtype, &sa.sin_addr, + addrbuf, sizeof(addrbuf)); - free(canon_hostname); - canon_hostname = xstrdup(hent->h_name); - free(ip_address); - ip_address = xstrdup(addrbuf); + sanitize_client(&hi->canon_hostname, hent->h_name); + strbuf_addstr(&hi->ip_address, addrbuf); + } #endif + hi->hostname_lookup_done = 1; } } +static void hostinfo_init(struct hostinfo *hi) +{ + memset(hi, 0, sizeof(*hi)); + strbuf_init(&hi->hostname, 0); + strbuf_init(&hi->canon_hostname, 0); + strbuf_init(&hi->ip_address, 0); + strbuf_init(&hi->tcp_port, 0); +} -static int execute(struct sockaddr *addr) +static void hostinfo_clear(struct hostinfo *hi) { - static char line[1000]; - int pktlen, len, i; + strbuf_release(&hi->hostname); + strbuf_release(&hi->canon_hostname); + strbuf_release(&hi->ip_address); + strbuf_release(&hi->tcp_port); +} - if (addr) { - char addrbuf[256] = ""; - int port = -1; +static int execute(void) +{ + char *line = packet_buffer; + int pktlen, len, i; + char *addr = getenv("REMOTE_ADDR"), *port = getenv("REMOTE_PORT"); + struct hostinfo hi; - if (addr->sa_family == AF_INET) { - struct sockaddr_in *sin_addr = (void *) addr; - inet_ntop(addr->sa_family, &sin_addr->sin_addr, addrbuf, sizeof(addrbuf)); - port = ntohs(sin_addr->sin_port); -#ifndef NO_IPV6 - } else if (addr && addr->sa_family == AF_INET6) { - struct sockaddr_in6 *sin6_addr = (void *) addr; + hostinfo_init(&hi); - char *buf = addrbuf; - *buf++ = '['; *buf = '\0'; /* stpcpy() is cool */ - inet_ntop(AF_INET6, &sin6_addr->sin6_addr, buf, sizeof(addrbuf) - 1); - strcat(buf, "]"); - - port = ntohs(sin6_addr->sin6_port); -#endif - } - loginfo("Connection from %s:%d", addrbuf, port); - setenv("REMOTE_ADDR", addrbuf, 1); - } - else { - unsetenv("REMOTE_ADDR"); - } + if (addr) + loginfo("Connection from %s:%s", addr, port); alarm(init_timeout ? init_timeout : timeout); - pktlen = packet_read_line(0, line, sizeof(line)); + pktlen = packet_read(0, NULL, NULL, packet_buffer, sizeof(packet_buffer), 0); alarm(0); len = strlen(line); @@ -580,76 +695,77 @@ static int execute(struct sockaddr *addr) pktlen--; } - free(hostname); - free(canon_hostname); - free(ip_address); - free(tcp_port); - hostname = canon_hostname = ip_address = tcp_port = NULL; - if (len != pktlen) - parse_host_arg(line + len + 1, pktlen - len - 1); + parse_host_arg(&hi, line + len + 1, pktlen - len - 1); for (i = 0; i < ARRAY_SIZE(daemon_service); i++) { struct daemon_service *s = &(daemon_service[i]); - int namelen = strlen(s->name); - if (!prefixcmp(line, "git-") && - !strncmp(s->name, line + 4, namelen) && - line[namelen + 4] == ' ') { + const char *arg; + + if (skip_prefix(line, "git-", &arg) && + skip_prefix(arg, s->name, &arg) && + *arg++ == ' ') { /* * Note: The directory here is probably context sensitive, * and might depend on the actual service being performed. */ - return run_service(line + namelen + 5, s); + int rc = run_service(arg, s, &hi); + hostinfo_clear(&hi); + return rc; } } + hostinfo_clear(&hi); logerror("Protocol error: '%s'", line); return -1; } +static int addrcmp(const struct sockaddr_storage *s1, + const struct sockaddr_storage *s2) +{ + const struct sockaddr *sa1 = (const struct sockaddr*) s1; + const struct sockaddr *sa2 = (const struct sockaddr*) s2; + + if (sa1->sa_family != sa2->sa_family) + return sa1->sa_family - sa2->sa_family; + if (sa1->sa_family == AF_INET) + return memcmp(&((struct sockaddr_in *)s1)->sin_addr, + &((struct sockaddr_in *)s2)->sin_addr, + sizeof(struct in_addr)); +#ifndef NO_IPV6 + if (sa1->sa_family == AF_INET6) + return memcmp(&((struct sockaddr_in6 *)s1)->sin6_addr, + &((struct sockaddr_in6 *)s2)->sin6_addr, + sizeof(struct in6_addr)); +#endif + return 0; +} + static int max_connections = 32; static unsigned int live_children; static struct child { struct child *next; - pid_t pid; + struct child_process cld; struct sockaddr_storage address; } *firstborn; -static void add_child(pid_t pid, struct sockaddr *addr, int addrlen) +static void add_child(struct child_process *cld, struct sockaddr *addr, socklen_t addrlen) { struct child *newborn, **cradle; - /* - * This must be xcalloc() -- we'll compare the whole sockaddr_storage - * but individual address may be shorter. - */ newborn = xcalloc(1, sizeof(*newborn)); live_children++; - newborn->pid = pid; + memcpy(&newborn->cld, cld, sizeof(*cld)); memcpy(&newborn->address, addr, addrlen); for (cradle = &firstborn; *cradle; cradle = &(*cradle)->next) - if (!memcmp(&(*cradle)->address, &newborn->address, - sizeof(newborn->address))) + if (!addrcmp(&(*cradle)->address, &newborn->address)) break; newborn->next = *cradle; *cradle = newborn; } -static void remove_child(pid_t pid) -{ - struct child **cradle, *blanket; - - for (cradle = &firstborn; (blanket = *cradle); cradle = &blanket->next) - if (blanket->pid == pid) { - *cradle = blanket->next; - live_children--; - free(blanket); - break; - } -} - /* * This gets called if the number of connections grows * past "max_connections". @@ -664,9 +780,8 @@ static void kill_some_child(void) return; for (; (next = blanket->next); blanket = next) - if (!memcmp(&blanket->address, &next->address, - sizeof(next->address))) { - kill(blanket->pid, SIGTERM); + if (!addrcmp(&blanket->address, &next->address)) { + kill(blanket->cld.pid, SIGTERM); break; } } @@ -676,18 +791,28 @@ static void check_dead_children(void) int status; pid_t pid; - while ((pid = waitpid(-1, &status, WNOHANG)) > 0) { - const char *dead = ""; - remove_child(pid); - if (!WIFEXITED(status) || (WEXITSTATUS(status) > 0)) - dead = " (with error)"; - loginfo("[%"PRIuMAX"] Disconnected%s", (uintmax_t)pid, dead); - } + struct child **cradle, *blanket; + for (cradle = &firstborn; (blanket = *cradle);) + if ((pid = waitpid(blanket->cld.pid, &status, WNOHANG)) > 1) { + const char *dead = ""; + if (status) + dead = " (with error)"; + loginfo("[%"PRIuMAX"] Disconnected%s", (uintmax_t)pid, dead); + + /* remove the child */ + *cradle = blanket->next; + live_children--; + free(blanket); + } else + cradle = &blanket->next; } -static void handle(int incoming, struct sockaddr *addr, int addrlen) +static char **cld_argv; +static void handle(int incoming, struct sockaddr *addr, socklen_t addrlen) { - pid_t pid; + struct child_process cld = CHILD_PROCESS_INIT; + char addrbuf[300] = "REMOTE_ADDR=", portbuf[300]; + char *env[] = { addrbuf, portbuf, NULL }; if (max_connections && live_children >= max_connections) { kill_some_child(); @@ -700,22 +825,36 @@ static void handle(int incoming, struct sockaddr *addr, int addrlen) } } - if ((pid = fork())) { - close(incoming); - if (pid < 0) { - logerror("Couldn't fork %s", strerror(errno)); - return; - } + if (addr->sa_family == AF_INET) { + struct sockaddr_in *sin_addr = (void *) addr; + inet_ntop(addr->sa_family, &sin_addr->sin_addr, addrbuf + 12, + sizeof(addrbuf) - 12); + snprintf(portbuf, sizeof(portbuf), "REMOTE_PORT=%d", + ntohs(sin_addr->sin_port)); +#ifndef NO_IPV6 + } else if (addr->sa_family == AF_INET6) { + struct sockaddr_in6 *sin6_addr = (void *) addr; - add_child(pid, addr, addrlen); - return; + char *buf = addrbuf + 12; + *buf++ = '['; *buf = '\0'; /* stpcpy() is cool */ + inet_ntop(AF_INET6, &sin6_addr->sin6_addr, buf, + sizeof(addrbuf) - 13); + strcat(buf, "]"); + + snprintf(portbuf, sizeof(portbuf), "REMOTE_PORT=%d", + ntohs(sin6_addr->sin6_port)); +#endif } - dup2(incoming, 0); - dup2(incoming, 1); - close(incoming); + cld.env = (const char **)env; + cld.argv = (const char **)cld_argv; + cld.in = incoming; + cld.out = dup(incoming); - exit(execute(addr)); + if (start_command(&cld)) + logerror("unable to fork"); + else + add_child(&cld, addr, addrlen); } static void child_handler(int signo) @@ -738,12 +877,40 @@ static int set_reuse_addr(int sockfd) &on, sizeof(on)); } +struct socketlist { + int *list; + size_t nr; + size_t alloc; +}; + +static const char *ip2str(int family, struct sockaddr *sin, socklen_t len) +{ +#ifdef NO_IPV6 + static char ip[INET_ADDRSTRLEN]; +#else + static char ip[INET6_ADDRSTRLEN]; +#endif + + switch (family) { #ifndef NO_IPV6 + case AF_INET6: + inet_ntop(family, &((struct sockaddr_in6*)sin)->sin6_addr, ip, len); + break; +#endif + case AF_INET: + inet_ntop(family, &((struct sockaddr_in*)sin)->sin_addr, ip, len); + break; + default: + strcpy(ip, "<unknown>"); + } + return ip; +} -static int socksetup(char *listen_addr, int listen_port, int **socklist_p) +#ifndef NO_IPV6 + +static int setup_named_sock(char *listen_addr, int listen_port, struct socketlist *socklist) { - int socknum = 0, *socklist = NULL; - int maxfd = -1; + int socknum = 0; char pbuf[NI_MAXSERV]; struct addrinfo hints, *ai0, *ai; int gai; @@ -757,8 +924,10 @@ static int socksetup(char *listen_addr, int listen_port, int **socklist_p) hints.ai_flags = AI_PASSIVE; gai = getaddrinfo(listen_addr, pbuf, &hints, &ai0); - if (gai) - die("getaddrinfo() failed: %s", gai_strerror(gai)); + if (gai) { + logerror("getaddrinfo() for %s failed: %s", listen_addr, gai_strerror(gai)); + return 0; + } for (ai = ai0; ai; ai = ai->ai_next) { int sockfd; @@ -782,15 +951,22 @@ static int socksetup(char *listen_addr, int listen_port, int **socklist_p) #endif if (set_reuse_addr(sockfd)) { + logerror("Could not set SO_REUSEADDR: %s", strerror(errno)); close(sockfd); continue; } if (bind(sockfd, ai->ai_addr, ai->ai_addrlen) < 0) { + logerror("Could not bind to %s: %s", + ip2str(ai->ai_family, ai->ai_addr, ai->ai_addrlen), + strerror(errno)); close(sockfd); continue; /* not fatal */ } if (listen(sockfd, 5) < 0) { + logerror("Could not listen to %s: %s", + ip2str(ai->ai_family, ai->ai_addr, ai->ai_addrlen), + strerror(errno)); close(sockfd); continue; /* not fatal */ } @@ -799,22 +975,19 @@ static int socksetup(char *listen_addr, int listen_port, int **socklist_p) if (flags >= 0) fcntl(sockfd, F_SETFD, flags | FD_CLOEXEC); - socklist = xrealloc(socklist, sizeof(int) * (socknum + 1)); - socklist[socknum++] = sockfd; - - if (maxfd < sockfd) - maxfd = sockfd; + ALLOC_GROW(socklist->list, socklist->nr + 1, socklist->alloc); + socklist->list[socklist->nr++] = sockfd; + socknum++; } freeaddrinfo(ai0); - *socklist_p = socklist; return socknum; } #else /* NO_IPV6 */ -static int socksetup(char *listen_addr, int listen_port, int **socklist_p) +static int setup_named_sock(char *listen_addr, int listen_port, struct socketlist *socklist) { struct sockaddr_in sin; int sockfd; @@ -837,16 +1010,23 @@ static int socksetup(char *listen_addr, int listen_port, int **socklist_p) return 0; if (set_reuse_addr(sockfd)) { + logerror("Could not set SO_REUSEADDR: %s", strerror(errno)); close(sockfd); return 0; } if ( bind(sockfd, (struct sockaddr *)&sin, sizeof sin) < 0 ) { + logerror("Could not bind to %s: %s", + ip2str(AF_INET, (struct sockaddr *)&sin, sizeof(sin)), + strerror(errno)); close(sockfd); return 0; } if (listen(sockfd, 5) < 0) { + logerror("Could not listen to %s: %s", + ip2str(AF_INET, (struct sockaddr *)&sin, sizeof(sin)), + strerror(errno)); close(sockfd); return 0; } @@ -855,22 +1035,39 @@ static int socksetup(char *listen_addr, int listen_port, int **socklist_p) if (flags >= 0) fcntl(sockfd, F_SETFD, flags | FD_CLOEXEC); - *socklist_p = xmalloc(sizeof(int)); - **socklist_p = sockfd; + ALLOC_GROW(socklist->list, socklist->nr + 1, socklist->alloc); + socklist->list[socklist->nr++] = sockfd; return 1; } #endif -static int service_loop(int socknum, int *socklist) +static void socksetup(struct string_list *listen_addr, int listen_port, struct socketlist *socklist) +{ + if (!listen_addr->nr) + setup_named_sock(NULL, listen_port, socklist); + else { + int i, socknum; + for (i = 0; i < listen_addr->nr; i++) { + socknum = setup_named_sock(listen_addr->items[i].string, + listen_port, socklist); + + if (socknum == 0) + logerror("unable to allocate any listen sockets for host %s on port %u", + listen_addr->items[i].string, listen_port); + } + } +} + +static int service_loop(struct socketlist *socklist) { struct pollfd *pfd; int i; - pfd = xcalloc(socknum, sizeof(struct pollfd)); + pfd = xcalloc(socklist->nr, sizeof(struct pollfd)); - for (i = 0; i < socknum; i++) { - pfd[i].fd = socklist[i]; + for (i = 0; i < socklist->nr; i++) { + pfd[i].fd = socklist->list[i]; pfd[i].events = POLLIN; } @@ -881,7 +1078,7 @@ static int service_loop(int socknum, int *socklist) check_dead_children(); - if (poll(pfd, socknum, -1) < 0) { + if (poll(pfd, socklist->nr, -1) < 0) { if (errno != EINTR) { logerror("Poll failed, resuming: %s", strerror(errno)); @@ -890,11 +1087,17 @@ static int service_loop(int socknum, int *socklist) continue; } - for (i = 0; i < socknum; i++) { + for (i = 0; i < socklist->nr; i++) { if (pfd[i].revents & POLLIN) { - struct sockaddr_storage ss; - unsigned int sslen = sizeof(ss); - int incoming = accept(pfd[i].fd, (struct sockaddr *)&ss, &sslen); + union { + struct sockaddr sa; + struct sockaddr_in sai; +#ifndef NO_IPV6 + struct sockaddr_in6 sai6; +#endif + } ss; + socklen_t sslen = sizeof(ss); + int incoming = accept(pfd[i].fd, &ss.sa, &sslen); if (incoming < 0) { switch (errno) { case EAGAIN: @@ -905,98 +1108,116 @@ static int service_loop(int socknum, int *socklist) die_errno("accept returned"); } } - handle(incoming, (struct sockaddr *)&ss, sslen); + handle(incoming, &ss.sa, sslen); } } } } -/* if any standard file descriptor is missing open it to /dev/null */ -static void sanitize_stdfds(void) +#ifdef NO_POSIX_GOODIES + +struct credentials; + +static void drop_privileges(struct credentials *cred) { - int fd = open("/dev/null", O_RDWR, 0); - while (fd != -1 && fd < 2) - fd = dup(fd); - if (fd == -1) - die_errno("open /dev/null or dup failed"); - if (fd > 2) - close(fd); + /* nothing */ } -static void daemonize(void) +static struct credentials *prepare_credentials(const char *user_name, + const char *group_name) { - switch (fork()) { - case 0: - break; - case -1: - die_errno("fork failed"); - default: - exit(0); - } - if (setsid() == -1) - die_errno("setsid failed"); - close(0); - close(1); - close(2); - sanitize_stdfds(); + die("--user not supported on this platform"); } -static void store_pid(const char *path) +#else + +struct credentials { + struct passwd *pass; + gid_t gid; +}; + +static void drop_privileges(struct credentials *cred) { - FILE *f = fopen(path, "w"); - if (!f) - die_errno("cannot open pid file '%s'", path); - if (fprintf(f, "%"PRIuMAX"\n", (uintmax_t) getpid()) < 0 || fclose(f) != 0) - die_errno("failed to write pid file '%s'", path); + if (cred && (initgroups(cred->pass->pw_name, cred->gid) || + setgid (cred->gid) || setuid(cred->pass->pw_uid))) + die("cannot drop privileges"); } -static int serve(char *listen_addr, int listen_port, struct passwd *pass, gid_t gid) +static struct credentials *prepare_credentials(const char *user_name, + const char *group_name) { - int socknum, *socklist; + static struct credentials c; - socknum = socksetup(listen_addr, listen_port, &socklist); - if (socknum == 0) - die("unable to allocate any listen sockets on host %s port %u", - listen_addr, listen_port); + c.pass = getpwnam(user_name); + if (!c.pass) + die("user not found - %s", user_name); - if (pass && gid && - (initgroups(pass->pw_name, gid) || setgid (gid) || - setuid(pass->pw_uid))) - die("cannot drop privileges"); + if (!group_name) + c.gid = c.pass->pw_gid; + else { + struct group *group = getgrnam(group_name); + if (!group) + die("group not found - %s", group_name); + + c.gid = group->gr_gid; + } - return service_loop(socknum, socklist); + return &c; +} +#endif + +static int serve(struct string_list *listen_addr, int listen_port, + struct credentials *cred) +{ + struct socketlist socklist = { NULL, 0, 0 }; + + socksetup(listen_addr, listen_port, &socklist); + if (socklist.nr == 0) + die("unable to allocate any listen sockets on port %u", + listen_port); + + drop_privileges(cred); + + loginfo("Ready to rumble"); + + return service_loop(&socklist); } int main(int argc, char **argv) { int listen_port = 0; - char *listen_addr = NULL; - int inetd_mode = 0; + struct string_list listen_addr = STRING_LIST_INIT_NODUP; + int serve_mode = 0, inetd_mode = 0; const char *pid_file = NULL, *user_name = NULL, *group_name = NULL; int detach = 0; - struct passwd *pass = NULL; - struct group *group; - gid_t gid = 0; + struct credentials *cred = NULL; int i; + git_setup_gettext(); + git_extract_argv0_path(argv[0]); for (i = 1; i < argc; i++) { char *arg = argv[i]; + const char *v; - if (!prefixcmp(arg, "--listen=")) { - listen_addr = xstrdup_tolower(arg + 9); + if (skip_prefix(arg, "--listen=", &v)) { + string_list_append(&listen_addr, xstrdup_tolower(v)); continue; } - if (!prefixcmp(arg, "--port=")) { + if (skip_prefix(arg, "--port=", &v)) { char *end; unsigned long n; - n = strtoul(arg+7, &end, 0); - if (arg[7] && !*end) { + n = strtoul(v, &end, 0); + if (*v && !*end) { listen_port = n; continue; } } + if (!strcmp(arg, "--serve")) { + serve_mode = 1; + continue; + } if (!strcmp(arg, "--inetd")) { inetd_mode = 1; log_syslog = 1; @@ -1014,16 +1235,20 @@ int main(int argc, char **argv) export_all_trees = 1; continue; } - if (!prefixcmp(arg, "--timeout=")) { - timeout = atoi(arg+10); + if (skip_prefix(arg, "--access-hook=", &v)) { + access_hook = v; + continue; + } + if (skip_prefix(arg, "--timeout=", &v)) { + timeout = atoi(v); continue; } - if (!prefixcmp(arg, "--init-timeout=")) { - init_timeout = atoi(arg+15); + if (skip_prefix(arg, "--init-timeout=", &v)) { + init_timeout = atoi(v); continue; } - if (!prefixcmp(arg, "--max-connections=")) { - max_connections = atoi(arg+18); + if (skip_prefix(arg, "--max-connections=", &v)) { + max_connections = atoi(v); if (max_connections < 0) max_connections = 0; /* unlimited */ continue; @@ -1032,16 +1257,16 @@ int main(int argc, char **argv) strict_paths = 1; continue; } - if (!prefixcmp(arg, "--base-path=")) { - base_path = arg+12; + if (skip_prefix(arg, "--base-path=", &v)) { + base_path = v; continue; } if (!strcmp(arg, "--base-path-relaxed")) { base_path_relaxed = 1; continue; } - if (!prefixcmp(arg, "--interpolated-path=")) { - interpolated_path = arg+20; + if (skip_prefix(arg, "--interpolated-path=", &v)) { + interpolated_path = v; continue; } if (!strcmp(arg, "--reuseaddr")) { @@ -1052,12 +1277,12 @@ int main(int argc, char **argv) user_path = ""; continue; } - if (!prefixcmp(arg, "--user-path=")) { - user_path = arg + 12; + if (skip_prefix(arg, "--user-path=", &v)) { + user_path = v; continue; } - if (!prefixcmp(arg, "--pid-file=")) { - pid_file = arg + 11; + if (skip_prefix(arg, "--pid-file=", &v)) { + pid_file = v; continue; } if (!strcmp(arg, "--detach")) { @@ -1065,28 +1290,36 @@ int main(int argc, char **argv) log_syslog = 1; continue; } - if (!prefixcmp(arg, "--user=")) { - user_name = arg + 7; + if (skip_prefix(arg, "--user=", &v)) { + user_name = v; + continue; + } + if (skip_prefix(arg, "--group=", &v)) { + group_name = v; continue; } - if (!prefixcmp(arg, "--group=")) { - group_name = arg + 8; + if (skip_prefix(arg, "--enable=", &v)) { + enable_service(v, 1); continue; } - if (!prefixcmp(arg, "--enable=")) { - enable_service(arg + 9, 1); + if (skip_prefix(arg, "--disable=", &v)) { + enable_service(v, 0); continue; } - if (!prefixcmp(arg, "--disable=")) { - enable_service(arg + 10, 0); + if (skip_prefix(arg, "--allow-override=", &v)) { + make_service_overridable(v, 1); continue; } - if (!prefixcmp(arg, "--allow-override=")) { - make_service_overridable(arg + 17, 1); + if (skip_prefix(arg, "--forbid-override=", &v)) { + make_service_overridable(v, 0); continue; } - if (!prefixcmp(arg, "--forbid-override=")) { - make_service_overridable(arg + 18, 0); + if (!strcmp(arg, "--informative-errors")) { + informative_errors = 1; + continue; + } + if (!strcmp(arg, "--no-informative-errors")) { + informative_errors = 0; continue; } if (!strcmp(arg, "--")) { @@ -1105,12 +1338,12 @@ int main(int argc, char **argv) set_die_routine(daemon_die); } else /* avoid splitting a message in the middle */ - setvbuf(stderr, NULL, _IOLBF, 0); + setvbuf(stderr, NULL, _IOFBF, 4096); - if (inetd_mode && (group_name || user_name)) - die("--user and --group are incompatible with --inetd"); + if (inetd_mode && (detach || group_name || user_name)) + die("--detach, --user and --group are incompatible with --inetd"); - if (inetd_mode && (listen_port || listen_addr)) + if (inetd_mode && (listen_port || (listen_addr.nr > 0))) die("--listen= and --port= are incompatible with --inetd"); else if (listen_port == 0) listen_port = DEFAULT_GIT_PORT; @@ -1118,21 +1351,8 @@ int main(int argc, char **argv) if (group_name && !user_name) die("--group supplied without --user"); - if (user_name) { - pass = getpwnam(user_name); - if (!pass) - die("user not found - %s", user_name); - - if (!group_name) - gid = pass->pw_gid; - else { - group = getgrnam(group_name); - if (!group) - die("group not found - %s", group_name); - - gid = group->gr_gid; - } - } + if (user_name) + cred = prepare_credentials(user_name, group_name); if (strict_paths && (!ok_paths || !*ok_paths)) die("option --strict-paths requires a whitelist"); @@ -1142,28 +1362,29 @@ int main(int argc, char **argv) base_path); if (inetd_mode) { - struct sockaddr_storage ss; - struct sockaddr *peer = (struct sockaddr *)&ss; - socklen_t slen = sizeof(ss); - if (!freopen("/dev/null", "w", stderr)) die_errno("failed to redirect stderr to /dev/null"); - - if (getpeername(0, peer, &slen)) - peer = NULL; - - return execute(peer); } + if (inetd_mode || serve_mode) + return execute(); + if (detach) { - daemonize(); - loginfo("Ready to rumble"); - } - else + if (daemonize()) + die("--detach not supported on this platform"); + } else sanitize_stdfds(); if (pid_file) - store_pid(pid_file); + write_file(pid_file, 1, "%"PRIuMAX"\n", (uintmax_t) getpid()); + + /* prepare argv for serving-processes */ + cld_argv = xmalloc(sizeof (char *) * (argc + 2)); + cld_argv[0] = argv[0]; /* git-daemon */ + cld_argv[1] = "--serve"; + for (i = 1; i < argc; ++i) + cld_argv[i+1] = argv[i]; + cld_argv[argc+1] = NULL; - return serve(listen_addr, listen_port, pass, gid); + return serve(&listen_addr, listen_port, cred); } |