From 3a9ed4bdee5032ecb9328aea51a752d69a2d966e Mon Sep 17 00:00:00 2001 From: Ilari Liusvaara Date: Tue, 12 Oct 2010 19:39:42 +0300 Subject: git-remote-fd This remote helper reflects raw smart remote transport stream back to the calling program. This is useful for example if some UI wants to handle ssh itself and not use hacks via GIT_SSH. Signed-off-by: Ilari Liusvaara Signed-off-by: Junio C Hamano --- Makefile | 1 + 1 file changed, 1 insertion(+) (limited to 'Makefile') diff --git a/Makefile b/Makefile index b7a62cfdf2..17a12dd054 100644 --- a/Makefile +++ b/Makefile @@ -723,6 +723,7 @@ BUILTIN_OBJS += builtin/read-tree.o BUILTIN_OBJS += builtin/receive-pack.o BUILTIN_OBJS += builtin/reflog.o BUILTIN_OBJS += builtin/remote.o +BUILTIN_OBJS += builtin/remote-fd.o BUILTIN_OBJS += builtin/replace.o BUILTIN_OBJS += builtin/rerere.o BUILTIN_OBJS += builtin/reset.o -- cgit v1.2.3 From 7f3ecebfcda9b32252a4791dc716c1e3d88c9f70 Mon Sep 17 00:00:00 2001 From: Ilari Liusvaara Date: Tue, 12 Oct 2010 19:39:43 +0300 Subject: git-remote-ext This remote helper invokes external command and passes raw smart transport stream through it. This is useful for instance for invoking ssh with one-off odd options, connecting to git services in unix domain sockets, in abstract namespace, using TLS or other secure protocols, etc... Signed-off-by: Ilari Liusvaara Signed-off-by: Junio C Hamano --- .gitignore | 1 + Documentation/git-remote-ext.txt | 125 ++++++++++++++++++++ Makefile | 1 + builtin.h | 1 + builtin/remote-ext.c | 248 +++++++++++++++++++++++++++++++++++++++ git.c | 1 + 6 files changed, 377 insertions(+) create mode 100644 Documentation/git-remote-ext.txt create mode 100644 builtin/remote-ext.c (limited to 'Makefile') diff --git a/.gitignore b/.gitignore index 89f37f42f7..87b833c9d8 100644 --- a/.gitignore +++ b/.gitignore @@ -113,6 +113,7 @@ /git-remote-ftp /git-remote-ftps /git-remote-fd +/git-remote-ext /git-remote-testgit /git-repack /git-replace diff --git a/Documentation/git-remote-ext.txt b/Documentation/git-remote-ext.txt new file mode 100644 index 0000000000..8fb260b54b --- /dev/null +++ b/Documentation/git-remote-ext.txt @@ -0,0 +1,125 @@ +git-remote-ext(1) +================= + +NAME +---- +git-remote-ext - Bridge smart transport to external command. + +SYNOPSIS +-------- +git remote add nick "ext::[ ...]" + +DESCRIPTION +----------- +This remote helper uses the specified 'program' to connect +to a remote git server. + +Data written to stdin of this specified 'program' is assumed +to be sent to git:// server, git-upload-pack, git-receive-pack +or git-upload-archive (depending on situation), and data read +from stdout of this program is assumed to be received from +the same service. + +Command and arguments are separated by unescaped space. + +The following sequences have a special meaning: + +'% ':: + Literal space in command or argument. + +'%%':: + Literal percent sign. + +'%s':: + Replaced with name (receive-pack, upload-pack, or + upload-archive) of the service git wants to invoke. + +'%S':: + Replaced with long name (git-receive-pack, + git-upload-pack, or git-upload-archive) of the service + git wants to invoke. + +'%G' (as argument):: + This argument will not be passed to 'program'. Instead, it + will cause helper to start by sending git:// service request to + remote side with service field set to approiate value and + repository field set to . Default is not to send + such request. ++ +This is useful if remote side is git:// server accessed over +some tunnel. + +'%V' (as argument):: + This argument will not be passed to 'program'. Instead it sets + the vhost field in git:// service request. Default is not to + send vhost in such request (if sent). + +ENVIRONMENT VARIABLES: +---------------------- + +GIT_TRANSLOOP_DEBUG:: + If set, prints debugging information about various reads/writes. + +ENVIRONMENT VARIABLES PASSED TO COMMAND: +---------------------------------------- + +GIT_EXT_SERVICE:: + Set to long name (git-upload-pack, etc...) of service helper needs + to invoke. + +GIT_EXT_SERVICE_NOPREFIX:: + Set to long name (upload-pack, etc...) of service helper needs + to invoke. + + +EXAMPLES: +--------- +This remote helper is transparently used by git when +you use commands such as "git fetch ", "git clone ", +, "git push " or "git remote add nick ", where +begins with `ext::`. Examples: + +"ext::ssh -i /home/foo/.ssh/somekey user@host.example %S 'foo/repo'":: + Like host.example:foo/repo, but use /home/foo/.ssh/somekey as + keypair and user as user on remote side. This avoids needing to + edit .ssh/config. + +"ext::socat -t3600 - ABSTRACT-CONNECT:/git-server %G/somerepo":: + Represents repository with path /somerepo accessable over + git protocol at abstract namespace address /git-server. + +"ext::git-server-alias foo %G/repo":: + Represents a repository with path /repo accessed using the + helper program "git-server-alias foo". The path to the + repository and type of request are not passed on the command + line but as part of the protocol stream, as usual with git:// + protocol. + +"ext::git-server-alias foo %G/repo %Vfoo":: + Represents a repository with path /repo accessed using the + helper program "git-server-alias foo". The hostname for the + remote server passed in the protocol stream will be "foo" + (this allows multiple virtual git servers to share a + link-level address). + +"ext::git-server-alias foo %G/repo% with% spaces %Vfoo":: + Represents a repository with path '/repo with spaces' accessed + using the helper program "git-server-alias foo". The hostname for + the remote server passed in the protocol stream will be "foo" + (this allows multiple virtual git servers to share a + link-level address). + +"ext::git-ssl foo.example /bar":: + Represents a repository accessed using the helper program + "git-ssl foo.example /bar". The type of request can be + determined by the helper using environment variables (see + above). + +Documentation +-------------- +Documentation by Ilari Liusvaara, Jonathan Nieder and the git list + + +GIT +--- +Part of the linkgit:git[1] suite diff --git a/Makefile b/Makefile index 17a12dd054..d8ada7892c 100644 --- a/Makefile +++ b/Makefile @@ -723,6 +723,7 @@ BUILTIN_OBJS += builtin/read-tree.o BUILTIN_OBJS += builtin/receive-pack.o BUILTIN_OBJS += builtin/reflog.o BUILTIN_OBJS += builtin/remote.o +BUILTIN_OBJS += builtin/remote-ext.o BUILTIN_OBJS += builtin/remote-fd.o BUILTIN_OBJS += builtin/replace.o BUILTIN_OBJS += builtin/rerere.o diff --git a/builtin.h b/builtin.h index b5da4adc65..c5bfabd01c 100644 --- a/builtin.h +++ b/builtin.h @@ -107,6 +107,7 @@ extern int cmd_read_tree(int argc, const char **argv, const char *prefix); extern int cmd_receive_pack(int argc, const char **argv, const char *prefix); extern int cmd_reflog(int argc, const char **argv, const char *prefix); extern int cmd_remote(int argc, const char **argv, const char *prefix); +extern int cmd_remote_ext(int argc, const char **argv, const char *prefix); extern int cmd_remote_fd(int argc, const char **argv, const char *prefix); extern int cmd_config(int argc, const char **argv, const char *prefix); extern int cmd_rerere(int argc, const char **argv, const char *prefix); diff --git a/builtin/remote-ext.c b/builtin/remote-ext.c new file mode 100644 index 0000000000..1d3f1cf3cc --- /dev/null +++ b/builtin/remote-ext.c @@ -0,0 +1,248 @@ +#include "git-compat-util.h" +#include "transport.h" +#include "run-command.h" + +/* + * URL syntax: + * 'command [arg1 [arg2 [...]]]' Invoke command with given arguments. + * Special characters: + * '% ': Literal space in argument. + * '%%': Literal percent sign. + * '%S': Name of service (git-upload-pack/git-upload-archive/ + * git-receive-pack. + * '%s': Same as \s, but with possible git- prefix stripped. + * '%G': Only allowed as first 'character' of argument. Do not pass this + * Argument to command, instead send this as name of repository + * in in-line git://-style request (also activates sending this + * style of request). + * '%V': Only allowed as first 'character' of argument. Used in + * conjunction with '%G': Do not pass this argument to command, + * instead send this as vhost in git://-style request (note: does + * not activate sending git:// style request). + */ + +static char *git_req; +static char *git_req_vhost; + +static char *strip_escapes(const char *str, const char *service, + const char **next) +{ + size_t rpos = 0; + int escape = 0; + char special = 0; + size_t pslen = 0; + size_t pSlen = 0; + size_t psoff = 0; + struct strbuf ret = STRBUF_INIT; + + /* Calculate prefix length for \s and lengths for \s and \S */ + if (!strncmp(service, "git-", 4)) + psoff = 4; + pSlen = strlen(service); + pslen = pSlen - psoff; + + /* Pass the service to command. */ + setenv("GIT_EXT_SERVICE", service, 1); + setenv("GIT_EXT_SERVICE_NOPREFIX", service + psoff, 1); + + /* Scan the length of argument. */ + while (str[rpos] && (escape || str[rpos] != ' ')) { + if (escape) { + switch (str[rpos]) { + case ' ': + case '%': + case 's': + case 'S': + break; + case 'G': + case 'V': + special = str[rpos]; + if (rpos == 1) + break; + /* Fall-through to error. */ + default: + die("Bad remote-ext placeholder '%%%c'.", + str[rpos]); + } + escape = 0; + } else + escape = (str[rpos] == '%'); + rpos++; + } + if (escape && !str[rpos]) + die("remote-ext command has incomplete placeholder"); + *next = str + rpos; + if (**next == ' ') + ++*next; /* Skip over space */ + + /* + * Do the actual placeholder substitution. The string will be short + * enough not to overflow integers. + */ + rpos = special ? 2 : 0; /* Skip first 2 bytes in specials. */ + escape = 0; + while (str[rpos] && (escape || str[rpos] != ' ')) { + if (escape) { + switch (str[rpos]) { + case ' ': + case '%': + strbuf_addch(&ret, str[rpos]); + break; + case 's': + strbuf_addstr(&ret, service + psoff); + break; + case 'S': + strbuf_addstr(&ret, service); + break; + } + escape = 0; + } else + switch (str[rpos]) { + case '%': + escape = 1; + break; + default: + strbuf_addch(&ret, str[rpos]); + break; + } + rpos++; + } + switch (special) { + case 'G': + git_req = strbuf_detach(&ret, NULL); + return NULL; + case 'V': + git_req_vhost = strbuf_detach(&ret, NULL); + return NULL; + default: + return strbuf_detach(&ret, NULL); + } +} + +/* Should be enough... */ +#define MAXARGUMENTS 256 + +static const char **parse_argv(const char *arg, const char *service) +{ + int arguments = 0; + int i; + const char **ret; + char *temparray[MAXARGUMENTS + 1]; + + while (*arg) { + char *expanded; + if (arguments == MAXARGUMENTS) + die("remote-ext command has too many arguments"); + expanded = strip_escapes(arg, service, &arg); + if (expanded) + temparray[arguments++] = expanded; + } + + ret = xmalloc((arguments + 1) * sizeof(char *)); + for (i = 0; i < arguments; i++) + ret[i] = temparray[i]; + ret[arguments] = NULL; + return (const char **)ret; +} + +static void send_git_request(int stdin_fd, const char *serv, const char *repo, + const char *vhost) +{ + size_t bufferspace; + size_t wpos = 0; + char *buffer; + + /* + * Request needs 12 bytes extra if there is vhost (xxxx \0host=\0) and + * 6 bytes extra (xxxx \0) if there is no vhost. + */ + if (vhost) + bufferspace = strlen(serv) + strlen(repo) + strlen(vhost) + 12; + else + bufferspace = strlen(serv) + strlen(repo) + 6; + + if (bufferspace > 0xFFFF) + die("Request too large to send"); + buffer = xmalloc(bufferspace); + + /* Make the packet. */ + wpos = sprintf(buffer, "%04x%s %s%c", (unsigned)bufferspace, + serv, repo, 0); + + /* Add vhost if any. */ + if (vhost) + sprintf(buffer + wpos, "host=%s%c", vhost, 0); + + /* Send the request */ + if (write_in_full(stdin_fd, buffer, bufferspace) < 0) + die_errno("Failed to send request"); + + free(buffer); +} + +static int run_child(const char *arg, const char *service) +{ + int r; + struct child_process child; + + memset(&child, 0, sizeof(child)); + child.in = -1; + child.out = -1; + child.err = 0; + child.argv = parse_argv(arg, service); + + if (start_command(&child) < 0) + die("Can't run specified command"); + + if (git_req) + send_git_request(child.in, service, git_req, git_req_vhost); + + r = bidirectional_transfer_loop(child.out, child.in); + if (!r) + r = finish_command(&child); + else + finish_command(&child); + return r; +} + +#define MAXCOMMAND 4096 + +static int command_loop(const char *child) +{ + char buffer[MAXCOMMAND]; + + while (1) { + size_t length; + if (!fgets(buffer, MAXCOMMAND - 1, stdin)) { + if (ferror(stdin)) + die("Comammand input error"); + exit(0); + } + /* Strip end of line characters. */ + length = strlen(buffer); + while (isspace((unsigned char)buffer[length - 1])) + buffer[--length] = 0; + + if (!strcmp(buffer, "capabilities")) { + printf("*connect\n\n"); + fflush(stdout); + } else if (!strncmp(buffer, "connect ", 8)) { + printf("\n"); + fflush(stdout); + return run_child(child, buffer + 8); + } else { + fprintf(stderr, "Bad command"); + return 1; + } + } +} + +int cmd_remote_ext(int argc, const char **argv, const char *prefix) +{ + if (argc < 3) { + fprintf(stderr, "Error: URL missing"); + exit(1); + } + + return command_loop(argv[2]); +} diff --git a/git.c b/git.c index b7b96b0dad..e95a1baea2 100644 --- a/git.c +++ b/git.c @@ -374,6 +374,7 @@ static void handle_internal_command(int argc, const char **argv) { "receive-pack", cmd_receive_pack }, { "reflog", cmd_reflog, RUN_SETUP }, { "remote", cmd_remote, RUN_SETUP }, + { "remote-ext", cmd_remote_ext }, { "remote-fd", cmd_remote_fd }, { "replace", cmd_replace, RUN_SETUP }, { "repo-config", cmd_config, RUN_SETUP_GENTLY }, -- cgit v1.2.3