| Message ID | 20240628002742.3421311-2-sandals@crustytoothpaste.net (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Proactive authentication over HTTP | expand |
"brian m. carlson" <sandals@crustytoothpaste.net> writes: > diff --git a/Documentation/config/http.txt b/Documentation/config/http.txt > index 2d4e0c9b86..2bacb2b862 100644 > --- a/Documentation/config/http.txt > +++ b/Documentation/config/http.txt > @@ -56,6 +56,21 @@ http.emptyAuth:: > a username in the URL, as libcurl normally requires a username for > authentication. > > +http.proactiveAuth:: > + Attempt authentication without first making an unauthenticated attempt and > + receiving a 401 response. This can be used to ensure that all requests are > + authenticated. If `http.emptyAuth` is set to true, this value has no effect. Well written. > ++ > +If the credential helper used specifies an authentication scheme (i.e., via the > +`authtype` field), that value will be used; if a username and password is > +provided without a scheme, then Basic authentication is used. The value of the > +option determines the scheme requested from the helper. Possible values are: > ++ > +-- > +* `basic` - Request Basic authentication from the helper. > +* `auto` - Don't request any scheme from the helper. > +-- What does "don't request" exactly mean? It is not like we are telling the helper "Don't give us anything", right? Are we telling the helper "Give us any username/password for the URL in any authentication scheme you know about?" As we are not getting an initial "401 Unauthorized", which is a good channel to convey WWW-Authenticate, Digest is not available to us in this context; we may end up using Basic---if the other side then says "No, I do not like basic, please use Diest in this realm with this nonce" with a "401 Unauthorized" with WWW-Authenticate, then all we gained was a chance to expose the username/password in plaintext (ok, that's still TLS protected in practice so it may not be a huge deal). Hopefully that wouldn't be a problem, but perhaps we would want to suggest that this mechanism should primarily be used when the user _knows_ that the other side is happy accepting you with Basic, or something, in the documentation? > diff --git a/http.c b/http.c > index 2dea2d03da..2e54eddb45 100644 > --- a/http.c > +++ b/http.c > @@ -106,12 +106,19 @@ static struct { > }; > #endif > > +enum proactive_auth { > + PROACTIVE_AUTH_NONE, > + PROACTIVE_AUTH_IF_CREDENTIALS, > + PROACTIVE_AUTH_AUTO, > + PROACTIVE_AUTH_BASIC, > +}; PROACTIVE_AUTH_NONE being at the first position to be assigned 0 in this enum has significance, because ... > static struct credential proxy_auth = CREDENTIAL_INIT; > static const char *curl_proxyuserpwd; > static char *curl_cookie_file; > static int curl_save_cookies; > struct credential http_auth = CREDENTIAL_INIT; > -static int http_proactive_auth; > +static enum proactive_auth http_proactive_auth; ... this implicitly initializes the variable to *_NONE and we do rely on that value. It may clarify what we are doing, if we are a bit more explicit, i.e., enum proactive_auth { PROACTIVE_AUTH_NONE = 0, ... It would give a hint to future developers that they shouldn't reorder the enum def without thinking. > +static int always_auth_proactively(void) > +{ > + return http_proactive_auth != PROACTIVE_AUTH_NONE && http_proactive_auth != PROACTIVE_AUTH_IF_CREDENTIALS; > +} An overly long line. > size_t fread_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_) > { > size_t size = eltsize * nmemb; > @@ -537,6 +549,18 @@ static int http_options(const char *var, const char *value, > return 0; > } > > + if (!strcmp("http.proactiveauth", var)) { > + if (value && !strcmp(value, "auto")) > + http_proactive_auth = PROACTIVE_AUTH_AUTO; > + else if (value && !strcmp(value, "basic")) > + http_proactive_auth = PROACTIVE_AUTH_BASIC; > + else if (!value) > + http_proactive_auth = PROACTIVE_AUTH_NONE; This is how you "reset" the variable that is set in lower-precedence configuration source back to the default, but use of "I exist therefore I represent true without giving any value" for that purpose is rather unusual. Even if this were about resetting a multi-valued configuration variable to empty, don't we usually allow an empty string to serve that purpose as well? And more importantly we apparently do not use this variable as multi-valued one---the above callback is a bog-standard "last one wins" single value variable. So instead of using the "I exist" true, I think it is a lot easier to see if you used an explicit string "none" for this purpose. If you insist to use "I exist" true, checking it upfront would allow you (and future developers) to lose many "value&&", i.e., if (!value || !*value) ... reset ...; else if (!strcmp(value, "auto")) ... but I do not see a strong reason to use the !value to begin with. I suspect that the usual if (!value) return config_error_nonbool(var); elseif (!strcmp(value, "none")) http_proactive_auth = PROACTIVE_AUTH_NONE; else if ... would be easier to read and maintain. In any case, the documentation update above failed to mention the mechanism to reset to the state that is equivalent to an unconfigured state, which needs an update. If we document what you do in your patch, it would read something like this, perhaps. + An earlier setting made in configuration files with lower-precedence can be overridden by setting it to a valueless truth, e.g., -- [http] proactiveAuth ; no "= value" needed here. -- And that is awkward, which is one of the reasons why I would prefer an explicit "none" (or "default" perhaps, if there were some reason you wanted to avoid it). > + else > + warning(_("Unknown value %s for http.proactiveauth"), value); > + return 0; > + } > + > @@ -578,14 +602,29 @@ static void init_curl_http_auth(CURL *result) > { > if ((!http_auth.username || !*http_auth.username) && > (!http_auth.credential || !*http_auth.credential)) { > - if (curl_empty_auth_enabled()) > + int empty_auth = curl_empty_auth_enabled(); > + if ((empty_auth != -1 && !always_auth_proactively()) || empty_auth == 1) { > curl_easy_setopt(result, CURLOPT_USERPWD, ":"); > - return; > + return; > + } else if (!always_auth_proactively()) { > + return; > + } else if (http_proactive_auth == PROACTIVE_AUTH_BASIC) { > + strvec_push(&http_auth.wwwauth_headers, "Basic"); > + } > } When http.proactiveauth explicitly says "basic", we push "Basic" to the strvec here. > credential_fill(&http_auth, 1); > > if (http_auth.password) { > + if (always_auth_proactively()) { But when http.proactiveauth is set to either "auto" or "basic", always_auth_proactively() returns true (because it is not set to *_NONE and it is not *_IF_CREDENTIALS) and we come here, to do curl_easy_setop() to use basic anyway. > + /* > + * We got a credential without an authtype and we don't > + * know what's available. Since our only two options at > + * the moment are auto (which defaults to basic) and > + * basic, use basic for now. > + */ > + curl_easy_setopt(result, CURLOPT_HTTPAUTH, CURLAUTH_BASIC); So users with "auto" will not see "Basic" in .wwwauth_headers strvec, while those with "basic" will. Is this intended? What is the expected difference in behaviour coming from this difference? Or am I simply reading the code incorrectly and not understanding what happens before the control reaches fwrite_wwwauth()? > + } > curl_easy_setopt(result, CURLOPT_USERNAME, http_auth.username); > curl_easy_setopt(result, CURLOPT_PASSWORD, http_auth.password); > } > @@ -1048,7 +1087,7 @@ static CURL *get_curl_handle(void) > #endif > } > > - if (http_proactive_auth) > + if (http_proactive_auth != PROACTIVE_AUTH_NONE) > init_curl_http_auth(result); Makes sense. > @@ -1292,7 +1331,8 @@ void http_init(struct remote *remote, const char *url, int proactive_auth) > if (curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK) > die("curl_global_init failed"); > > - http_proactive_auth = proactive_auth; > + if (proactive_auth && http_proactive_auth == PROACTIVE_AUTH_NONE) > + http_proactive_auth = PROACTIVE_AUTH_IF_CREDENTIALS; The webdav http-push is the only caller of http_init() with the proactive_auth parameter set to true. In such a case, if we do not see the configuration variable left/set to the default, we force the "if-credentials" behaviour. IOW, if http.proactive_auth is set to some value, we leave it as-is even for http-push (which wants to use the "if-credentials" behaviour). I wonder if there are cases where you would want to do the proactive-auth for fetches (which you couldn't do before), but you want to drive http-push with if-credentials, and if so, if this changes the behaviour in a way that is visible to the end-user. Or perhaps http-push over webdav outlived its usefulness and we should send a patch to Documentation/BreakingChanges.txt to declare its deprecation and removal, in which case there is nothing to wonder or be worried here ;-) > @@ -1788,6 +1828,8 @@ static int handle_curl_result(struct slot_results *results) > return HTTP_REAUTH; > } > credential_reject(&http_auth); > + if (always_auth_proactively()) > + http_proactive_auth = PROACTIVE_AUTH_NONE; Once we see a failure, there is not much point in doing the proactive-auth to the same destination in requests we are going to make from now on. Makes sense. > @@ -2184,7 +2226,12 @@ static int http_request_reauth(const char *url, > struct http_get_options *options) > { > int i = 3; > - int ret = http_request(url, result, target, options); > + int ret; > + > + if (always_auth_proactively()) > + credential_fill(&http_auth, 1); > + > + ret = http_request(url, result, target, options); > > if (ret != HTTP_OK && ret != HTTP_REAUTH) > return ret; OK, if we need to auth proactively, of course we need to fill the credential before making a request. Makes sense. Thanks.
On 2024-06-28 at 18:16:43, Junio C Hamano wrote: > "brian m. carlson" <sandals@crustytoothpaste.net> writes: > > > diff --git a/Documentation/config/http.txt b/Documentation/config/http.txt > > index 2d4e0c9b86..2bacb2b862 100644 > > --- a/Documentation/config/http.txt > > +++ b/Documentation/config/http.txt > > @@ -56,6 +56,21 @@ http.emptyAuth:: > > a username in the URL, as libcurl normally requires a username for > > authentication. > > > > +http.proactiveAuth:: > > + Attempt authentication without first making an unauthenticated attempt and > > + receiving a 401 response. This can be used to ensure that all requests are > > + authenticated. If `http.emptyAuth` is set to true, this value has no effect. > > Well written. > > > ++ > > +If the credential helper used specifies an authentication scheme (i.e., via the > > +`authtype` field), that value will be used; if a username and password is > > +provided without a scheme, then Basic authentication is used. The value of the > > +option determines the scheme requested from the helper. Possible values are: > > ++ > > +-- > > +* `basic` - Request Basic authentication from the helper. > > +* `auto` - Don't request any scheme from the helper. > > +-- > > What does "don't request" exactly mean? It is not like we are > telling the helper "Don't give us anything", right? Are we telling > the helper "Give us any username/password for the URL in any > authentication scheme you know about?" It means we don't send a `wwwauth[]` entry in the request. We are giving the helper carte blanche to decide what scheme is best (maybe it knows we want Bearer, for example). > As we are not getting an initial "401 Unauthorized", which is a good > channel to convey WWW-Authenticate, Digest is not available to us in > this context; we may end up using Basic---if the other side then > says "No, I do not like basic, please use Diest in this realm with > this nonce" with a "401 Unauthorized" with WWW-Authenticate, then > all we gained was a chance to expose the username/password in > plaintext (ok, that's still TLS protected in practice so it may not > be a huge deal). Hopefully that wouldn't be a problem, but perhaps > we would want to suggest that this mechanism should primarily be > used when the user _knows_ that the other side is happy accepting > you with Basic, or something, in the documentation? I think it might suffice to say that TLS should always be used with this configuration. The documentation is very clear that it will use Basic if no scheme is provided, so presumably the user is either very confident in their helper configuration (e.g., they know for certain that the helper will always emit an `authtype` field because they've so configured it), or they're willing to accept the risk that the password is sent with basic auth. > PROACTIVE_AUTH_NONE being at the first position to be assigned 0 > in this enum has significance, because ... > > > static struct credential proxy_auth = CREDENTIAL_INIT; > > static const char *curl_proxyuserpwd; > > static char *curl_cookie_file; > > static int curl_save_cookies; > > struct credential http_auth = CREDENTIAL_INIT; > > -static int http_proactive_auth; > > +static enum proactive_auth http_proactive_auth; > > ... this implicitly initializes the variable to *_NONE and we do > rely on that value. It may clarify what we are doing, if we are a > bit more explicit, i.e., > > enum proactive_auth { > PROACTIVE_AUTH_NONE = 0, > ... > > It would give a hint to future developers that they shouldn't > reorder the enum def without thinking. Sure, that seems like a good idea. > > +static int always_auth_proactively(void) > > +{ > > + return http_proactive_auth != PROACTIVE_AUTH_NONE && http_proactive_auth != PROACTIVE_AUTH_IF_CREDENTIALS; > > +} > > An overly long line. Will fix. > > size_t fread_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_) > > { > > size_t size = eltsize * nmemb; > > @@ -537,6 +549,18 @@ static int http_options(const char *var, const char *value, > > return 0; > > } > > > > + if (!strcmp("http.proactiveauth", var)) { > > + if (value && !strcmp(value, "auto")) > > + http_proactive_auth = PROACTIVE_AUTH_AUTO; > > + else if (value && !strcmp(value, "basic")) > > + http_proactive_auth = PROACTIVE_AUTH_BASIC; > > + else if (!value) > > + http_proactive_auth = PROACTIVE_AUTH_NONE; > > This is how you "reset" the variable that is set in lower-precedence > configuration source back to the default, but use of "I exist > therefore I represent true without giving any value" for that > purpose is rather unusual. Even if this were about resetting a > multi-valued configuration variable to empty, don't we usually allow > an empty string to serve that purpose as well? > > And more importantly we apparently do not use this variable as > multi-valued one---the above callback is a bog-standard "last one > wins" single value variable. > > So instead of using the "I exist" true, I think it is a lot easier > to see if you used an explicit string "none" for this purpose. Okay, I think that seems reasonable. > > credential_fill(&http_auth, 1); > > > > if (http_auth.password) { > > + if (always_auth_proactively()) { > > But when http.proactiveauth is set to either "auto" or "basic", > always_auth_proactively() returns true (because it is not set to > *_NONE and it is not *_IF_CREDENTIALS) and we come here, to do > curl_easy_setop() to use basic anyway. Yes, iff there's a password. The reason is that it isn't sufficient for libcurl to have a username and password to send authentication. Either we have to explicitly fill in the Authorization header (which we do with `authtype` and `credential`) or we have to specify exactly one authentication scheme; otherwise, libcurl doesn't auth. Note that entire branch is not taken if we have `authtype` and `credential`; that is handled elsewhere. This is subtle, so I'll mention it in the commit message on a reroll. > > + /* > > + * We got a credential without an authtype and we don't > > + * know what's available. Since our only two options at > > + * the moment are auto (which defaults to basic) and > > + * basic, use basic for now. > > + */ > > + curl_easy_setopt(result, CURLOPT_HTTPAUTH, CURLAUTH_BASIC); > > So users with "auto" will not see "Basic" in .wwwauth_headers > strvec, while those with "basic" will. Is this intended? What is > the expected difference in behaviour coming from this difference? Yes. The difference is that a credential helper supporting multiple schemes will (or at least _should_) read the `wwwauth[]` entry and say, "Oh, the server only supports Basic auth, so I must send Basic auth", whereas not sending anything tells it that it may choose freely. For example, a helper might legitimately return Bearer for the case where we don't send a `wwwauth[]` entry (which would be handled differently), whereas it probably would not want to do that when the option is set to `basic`. > > @@ -1292,7 +1331,8 @@ void http_init(struct remote *remote, const char *url, int proactive_auth) > > if (curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK) > > die("curl_global_init failed"); > > > > - http_proactive_auth = proactive_auth; > > + if (proactive_auth && http_proactive_auth == PROACTIVE_AUTH_NONE) > > + http_proactive_auth = PROACTIVE_AUTH_IF_CREDENTIALS; > > The webdav http-push is the only caller of http_init() with the > proactive_auth parameter set to true. In such a case, if we do not > see the configuration variable left/set to the default, we force the > "if-credentials" behaviour. IOW, if http.proactive_auth is set to > some value, we leave it as-is even for http-push (which wants to use > the "if-credentials" behaviour). Correct. When this option was a boolean, the if-credentials behaviour was what happened when the option was true. > I wonder if there are cases where you would want to do the > proactive-auth for fetches (which you couldn't do before), but you > want to drive http-push with if-credentials, and if so, if this > changes the behaviour in a way that is visible to the end-user. I think that's remarkably unlikely. Pushing effectively always requires some sort of authentication because you don't want random people modifying your codebase/writing project/other collection of bits. That's like security 101. Therefore, you're _going_ to authenticate sooner or later on push. The only case where if-credentials is helpful is what I mentioned about t5540, where we actually have an open push. That isn't a real world use case for security reasons, but using TLS certificates to authenticate and not otherwise sending credentials, which _looks_ the same to this code, is legitimate. However, you wouldn't configure TLS certificates for push only and use regular auth for fetch, since you'd already have the TLS certificate on the client and you'd have already requested the certificate when establishing the TLS connection. Moreover, there's no reason that you _would_ want to auth for fetches or clones and not for pushes; if your goal is to make it easier to throttle heavy users, say, pushes are more expensive because you have to run pre-receive hooks and fsck the data. Perhaps someone has come up with such an unusual use case and is still using the WebDAV approach, and in such a case, we can simply let them send a nice patch to implement http.pushProactiveAuth for that case. In the mean time, I'm happy to let one option control both. > Or perhaps http-push over webdav outlived its usefulness and we > should send a patch to Documentation/BreakingChanges.txt to declare > its deprecation and removal, in which case there is nothing to > wonder or be worried here ;-) I think cgit still supports it because it's easier to implement in a CGI-style piece of code, and maybe that's useful. While I don't use it, it can be easier to set up in certain environments, and I don't really want to be the one to announce its demise. Anyway, thanks for the review, and I'll try to get a reroll out relatively soon. I have a couple days of vacation with the Canada Day holiday, so hopefully I can find some time to get one out then.
"brian m. carlson" <sandals@crustytoothpaste.net> writes: >> > +* `basic` - Request Basic authentication from the helper. >> > +* `auto` - Don't request any scheme from the helper. >> > +-- >> >> What does "don't request" exactly mean? It is not like we are >> telling the helper "Don't give us anything", right? Are we telling >> the helper "Give us any username/password for the URL in any >> authentication scheme you know about?" > > It means we don't send a `wwwauth[]` entry in the request. We are > giving the helper carte blanche to decide what scheme is best (maybe it > knows we want Bearer, for example). Well, at least I couldn't read the proposed document update and read that much out of it, and I suspect there may be other readers who will share my confusion. I think the source of the confusion is that "don't request" does not automatically imply "allow the helper to pick any scheme as it sees fit" if you do not know how helper is designed to behave when it is not requested "any scheme". `basic` - Request Basic authentication from the helper. `auto` - Ask the helper to pick an appropriate scheme. `none` - Disable proactive authentication. or something, perhaps? Thanks.
On 2024-06-28 at 22:18:37, Junio C Hamano wrote: > Well, at least I couldn't read the proposed document update and read > that much out of it, and I suspect there may be other readers who > will share my confusion. I think the source of the confusion is > that "don't request" does not automatically imply "allow the helper > to pick any scheme as it sees fit" if you do not know how helper is > designed to behave when it is not requested "any scheme". > > `basic` - Request Basic authentication from the helper. > `auto` - Ask the helper to pick an appropriate scheme. > `none` - Disable proactive authentication. > > or something, perhaps? That sounds good. I appreciate you providing some language that would be less confusing to you, because it will probably be less confusing to others as well.
"brian m. carlson" <sandals@crustytoothpaste.net> writes: > On 2024-06-28 at 22:18:37, Junio C Hamano wrote: >> Well, at least I couldn't read the proposed document update and read >> that much out of it, and I suspect there may be other readers who >> will share my confusion. I think the source of the confusion is >> that "don't request" does not automatically imply "allow the helper >> to pick any scheme as it sees fit" if you do not know how helper is >> designed to behave when it is not requested "any scheme". >> >> `basic` - Request Basic authentication from the helper. >> `auto` - Ask the helper to pick an appropriate scheme. >> `none` - Disable proactive authentication. >> >> or something, perhaps? > > That sounds good. I appreciate you providing some language that would > be less confusing to you, because it will probably be less confusing to > others as well. Thanks. Giving a possible alternative, when you are certain you understood what you originally found confusing, is probably one of the things we should add as a tip to ReviewingPatches document (do we have one already--- #leftoverbits ?).
diff --git a/Documentation/config/http.txt b/Documentation/config/http.txt index 2d4e0c9b86..2bacb2b862 100644 --- a/Documentation/config/http.txt +++ b/Documentation/config/http.txt @@ -56,6 +56,21 @@ http.emptyAuth:: a username in the URL, as libcurl normally requires a username for authentication. +http.proactiveAuth:: + Attempt authentication without first making an unauthenticated attempt and + receiving a 401 response. This can be used to ensure that all requests are + authenticated. If `http.emptyAuth` is set to true, this value has no effect. ++ +If the credential helper used specifies an authentication scheme (i.e., via the +`authtype` field), that value will be used; if a username and password is +provided without a scheme, then Basic authentication is used. The value of the +option determines the scheme requested from the helper. Possible values are: ++ +-- +* `basic` - Request Basic authentication from the helper. +* `auto` - Don't request any scheme from the helper. +-- + http.delegation:: Control GSSAPI credential delegation. The delegation is disabled by default in libcurl since version 7.21.7. Set parameter to tell diff --git a/http.c b/http.c index 2dea2d03da..2e54eddb45 100644 --- a/http.c +++ b/http.c @@ -106,12 +106,19 @@ static struct { }; #endif +enum proactive_auth { + PROACTIVE_AUTH_NONE, + PROACTIVE_AUTH_IF_CREDENTIALS, + PROACTIVE_AUTH_AUTO, + PROACTIVE_AUTH_BASIC, +}; + static struct credential proxy_auth = CREDENTIAL_INIT; static const char *curl_proxyuserpwd; static char *curl_cookie_file; static int curl_save_cookies; struct credential http_auth = CREDENTIAL_INIT; -static int http_proactive_auth; +static enum proactive_auth http_proactive_auth; static char *user_agent; static int curl_empty_auth = -1; @@ -146,6 +153,11 @@ static int http_schannel_check_revoke = 1; */ static int http_schannel_use_ssl_cainfo; +static int always_auth_proactively(void) +{ + return http_proactive_auth != PROACTIVE_AUTH_NONE && http_proactive_auth != PROACTIVE_AUTH_IF_CREDENTIALS; +} + size_t fread_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_) { size_t size = eltsize * nmemb; @@ -537,6 +549,18 @@ static int http_options(const char *var, const char *value, return 0; } + if (!strcmp("http.proactiveauth", var)) { + if (value && !strcmp(value, "auto")) + http_proactive_auth = PROACTIVE_AUTH_AUTO; + else if (value && !strcmp(value, "basic")) + http_proactive_auth = PROACTIVE_AUTH_BASIC; + else if (!value) + http_proactive_auth = PROACTIVE_AUTH_NONE; + else + warning(_("Unknown value %s for http.proactiveauth"), value); + return 0; + } + /* Fall back on the default ones */ return git_default_config(var, value, ctx, data); } @@ -578,14 +602,29 @@ static void init_curl_http_auth(CURL *result) { if ((!http_auth.username || !*http_auth.username) && (!http_auth.credential || !*http_auth.credential)) { - if (curl_empty_auth_enabled()) + int empty_auth = curl_empty_auth_enabled(); + if ((empty_auth != -1 && !always_auth_proactively()) || empty_auth == 1) { curl_easy_setopt(result, CURLOPT_USERPWD, ":"); - return; + return; + } else if (!always_auth_proactively()) { + return; + } else if (http_proactive_auth == PROACTIVE_AUTH_BASIC) { + strvec_push(&http_auth.wwwauth_headers, "Basic"); + } } credential_fill(&http_auth, 1); if (http_auth.password) { + if (always_auth_proactively()) { + /* + * We got a credential without an authtype and we don't + * know what's available. Since our only two options at + * the moment are auto (which defaults to basic) and + * basic, use basic for now. + */ + curl_easy_setopt(result, CURLOPT_HTTPAUTH, CURLAUTH_BASIC); + } curl_easy_setopt(result, CURLOPT_USERNAME, http_auth.username); curl_easy_setopt(result, CURLOPT_PASSWORD, http_auth.password); } @@ -1048,7 +1087,7 @@ static CURL *get_curl_handle(void) #endif } - if (http_proactive_auth) + if (http_proactive_auth != PROACTIVE_AUTH_NONE) init_curl_http_auth(result); if (getenv("GIT_SSL_VERSION")) @@ -1292,7 +1331,8 @@ void http_init(struct remote *remote, const char *url, int proactive_auth) if (curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK) die("curl_global_init failed"); - http_proactive_auth = proactive_auth; + if (proactive_auth && http_proactive_auth == PROACTIVE_AUTH_NONE) + http_proactive_auth = PROACTIVE_AUTH_IF_CREDENTIALS; if (remote && remote->http_proxy) curl_http_proxy = xstrdup(remote->http_proxy); @@ -1788,6 +1828,8 @@ static int handle_curl_result(struct slot_results *results) return HTTP_REAUTH; } credential_reject(&http_auth); + if (always_auth_proactively()) + http_proactive_auth = PROACTIVE_AUTH_NONE; return HTTP_NOAUTH; } else { http_auth_methods &= ~CURLAUTH_GSSNEGOTIATE; @@ -2184,7 +2226,12 @@ static int http_request_reauth(const char *url, struct http_get_options *options) { int i = 3; - int ret = http_request(url, result, target, options); + int ret; + + if (always_auth_proactively()) + credential_fill(&http_auth, 1); + + ret = http_request(url, result, target, options); if (ret != HTTP_OK && ret != HTTP_REAUTH) return ret; diff --git a/t/t5563-simple-http-auth.sh b/t/t5563-simple-http-auth.sh index 4af796de67..ba03f6a09f 100755 --- a/t/t5563-simple-http-auth.sh +++ b/t/t5563-simple-http-auth.sh @@ -178,6 +178,122 @@ test_expect_success 'access using basic auth invalid credentials' ' EOF ' +test_expect_success 'access using basic proactive auth' ' + test_when_finished "per_test_cleanup" && + + set_credential_reply get <<-EOF && + username=alice + password=secret-passwd + EOF + + # Basic base64(alice:secret-passwd) + cat >"$HTTPD_ROOT_PATH/custom-auth.valid" <<-EOF && + id=1 creds=Basic YWxpY2U6c2VjcmV0LXBhc3N3ZA== + EOF + + cat >"$HTTPD_ROOT_PATH/custom-auth.challenge" <<-EOF && + id=1 status=200 + id=default status=403 + EOF + + test_config_global credential.helper test-helper && + test_config_global http.proactiveAuth basic && + git ls-remote "$HTTPD_URL/custom_auth/repo.git" && + + expect_credential_query get <<-EOF && + capability[]=authtype + capability[]=state + protocol=http + host=$HTTPD_DEST + wwwauth[]=Basic + EOF + + expect_credential_query store <<-EOF + protocol=http + host=$HTTPD_DEST + username=alice + password=secret-passwd + EOF +' + +test_expect_success 'access using auto proactive auth with basic default' ' + test_when_finished "per_test_cleanup" && + + set_credential_reply get <<-EOF && + username=alice + password=secret-passwd + EOF + + # Basic base64(alice:secret-passwd) + cat >"$HTTPD_ROOT_PATH/custom-auth.valid" <<-EOF && + id=1 creds=Basic YWxpY2U6c2VjcmV0LXBhc3N3ZA== + EOF + + cat >"$HTTPD_ROOT_PATH/custom-auth.challenge" <<-EOF && + id=1 status=200 + id=default status=403 + EOF + + test_config_global credential.helper test-helper && + test_config_global http.proactiveAuth auto && + git ls-remote "$HTTPD_URL/custom_auth/repo.git" && + + expect_credential_query get <<-EOF && + capability[]=authtype + capability[]=state + protocol=http + host=$HTTPD_DEST + EOF + + expect_credential_query store <<-EOF + protocol=http + host=$HTTPD_DEST + username=alice + password=secret-passwd + EOF +' + +test_expect_success 'access using auto proactive auth with authtype from credential helper' ' + test_when_finished "per_test_cleanup" && + + set_credential_reply get <<-EOF && + capability[]=authtype + authtype=Bearer + credential=YS1naXQtdG9rZW4= + EOF + + # Basic base64(a-git-token) + cat >"$HTTPD_ROOT_PATH/custom-auth.valid" <<-EOF && + id=1 creds=Bearer YS1naXQtdG9rZW4= + EOF + + CHALLENGE="$HTTPD_ROOT_PATH/custom-auth.challenge" && + + cat >"$HTTPD_ROOT_PATH/custom-auth.challenge" <<-EOF && + id=1 status=200 + id=default status=403 + EOF + + test_config_global credential.helper test-helper && + test_config_global http.proactiveAuth auto && + git ls-remote "$HTTPD_URL/custom_auth/repo.git" && + + expect_credential_query get <<-EOF && + capability[]=authtype + capability[]=state + protocol=http + host=$HTTPD_DEST + EOF + + expect_credential_query store <<-EOF + capability[]=authtype + authtype=Bearer + credential=YS1naXQtdG9rZW4= + protocol=http + host=$HTTPD_DEST + EOF +' + test_expect_success 'access using basic auth with extra challenges' ' test_when_finished "per_test_cleanup" &&
When making a request over HTTP(S), Git only sends authentication if it receives a 401 response. Thus, if a repository is open to the public for reading, Git will typically never ask for authentication for fetches and clones. However, there may be times when a user would like to authenticate nevertheless. For example, a forge may give higher rate limits to users who authenticate because they are easier to contact in case of excessive use. Or it may be useful for a known heavy user, such as an internal service, to proactively authenticate so its use can be monitored and, if necessary, throttled. Let's make this possible with a new option, "http.proactiveAuth". This option specifies a type of authentication which can be used to authenticate against the host in question. This is necessary because we lack the WWW-Authenticate header to provide us details; similarly, we cannot accept certain types of authentication because we require information from the server, such as a nonce or challenge, to successfully authenticate. Note that the existing http_proactive_auth variable signifies proactive auth if there are already credentials, which is different from the functionality we're adding, which always seeks credentials even if none are provided. Nonetheless, t5540 tests the existing behavior for WebDAV-based pushes to an open repository without credentials, so we preserve it. While at first this may seem an insecure and bizarre decision, it may be that authentication is done with TLS certificates, in which case it might actually provide a quite high level of security. Expand the variable to use an enum to handle the additional cases and a helper function to distinguish our new cases from the old ones. Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> --- Documentation/config/http.txt | 15 +++++ http.c | 59 +++++++++++++++-- t/t5563-simple-http-auth.sh | 116 ++++++++++++++++++++++++++++++++++ 3 files changed, 184 insertions(+), 6 deletions(-)