# [PATCH 2/4] git-imap-send: Add support for SSL. 8 messages from 2008-07-08 to 2008-07-10. Participants: Robert Shearman, Junio C Hamano, Abhijit Menon-Sen, Rob Shearman, Josh Triplett, Jeff King. Thread: https://gitlist.dev/t/14356 ## Robert Shearman, 2008-07-08 22:18 Subject: [PATCH 2/4] git-imap-send: Add support for SSL. Message-ID: <1215555496-21335-2-git-send-email-robertshearman@gmail.com> URL: https://gitlist.dev/e/1215555496-21335-2-git-send-email-robertshearman%40gmail.com ``` Allow SSL to be used when a imaps:// URL is used for the host name. Also, automatically use TLS when not using imaps:// by using the IMAP STARTTLS command, if the server supports it. Tested with Courier and Gimap IMAP servers. --- Documentation/git-imap-send.txt | 5 +- Makefile | 4 +- imap-send.c | 166 +++++++++++++++++++++++++++++++++++---- 3 files changed, 157 insertions(+), 18 deletions(-) diff --git a/Documentation/git-imap-send.txt b/Documentation/git-imap-send.txt index b3d8da3..e4a5873 100644 --- a/Documentation/git-imap-send.txt +++ b/Documentation/git-imap-send.txt @@ -37,10 +37,11 @@ configuration file (shown with examples): Tunnel = "ssh -q user@server.com /usr/bin/imapd ./Maildir 2> /dev/null" [imap] - Host = imap.server.com + Host = imaps://imap.example.com User = bob Pass = pwd - Port = 143 + Port = 993 + sslverify = false .......................... diff --git a/Makefile b/Makefile index bddd1a7..d9265f7 100644 --- a/Makefile +++ b/Makefile @@ -1193,7 +1193,9 @@ endif git-%$X: %.o $(GITLIBS) $(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) $(LIBS) -git-imap-send$X: imap-send.o $(LIB_FILE) +git-imap-send$X: imap-send.o $(GITLIBS) + $(QUIET_LINK)$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) \ + $(LIBS) $(OPENSSL_LINK) $(OPENSSL_LIBSSL) http.o http-walker.o http-push.o transport.o: http.h diff --git a/imap-send.c b/imap-send.c index 89a1532..d138726 100644 --- a/imap-send.c +++ b/imap-send.c @@ -23,6 +23,12 @@ */ #include "cache.h" +#ifdef NO_OPENSSL +typedef void *SSL; +#else +# include +# include +#endif typedef struct store_conf { char *name; @@ -129,6 +135,8 @@ typedef struct imap_server_conf { int port; char *user; char *pass; + int use_ssl; + int ssl_verify; } imap_server_conf_t; typedef struct imap_store_conf { @@ -148,6 +156,7 @@ typedef struct _list { typedef struct { int fd; + SSL *ssl; } Socket_t; typedef struct { @@ -201,6 +210,7 @@ enum CAPABILITY { UIDPLUS, LITERALPLUS, NAMESPACE, + STARTTLS, }; static const char *cap_list[] = { @@ -208,6 +218,7 @@ static const char *cap_list[] = { "UIDPLUS", "LITERAL+", "NAMESPACE", + "STARTTLS", }; #define RESP_OK 0 @@ -225,19 +236,101 @@ static const char *Flags[] = { "Deleted", }; +#ifndef NO_OPENSSL +static void ssl_socket_perror(const char *func) +{ + fprintf(stderr, "%s: %s\n", func, ERR_error_string(ERR_get_error(), 0)); +} +#endif + static void socket_perror( const char *func, Socket_t *sock, int ret ) { - if (ret < 0) - perror( func ); +#ifndef NO_OPENSSL + if (sock->ssl) { + int sslerr = SSL_get_error(sock->ssl, ret); + switch (sslerr) { + case SSL_ERROR_NONE: + break; + case SSL_ERROR_SYSCALL: + perror("SSL_connect"); + break; + default: + ssl_socket_perror("SSL_connect"); + break; + } + } else +#endif + { + if (ret < 0) + perror(func); + else + fprintf(stderr, "%s: unexpected EOF\n", func); + } +} + +static int ssl_socket_connect(Socket_t *sock, int use_tls_only, int verify) +{ +#ifdef NO_OPENSSL + fprintf(stderr, "SSL requested but SSL support not compiled in\n"); + return -1; +#else + SSL_METHOD *meth; + SSL_CTX *ctx; + int ret; + + SSL_library_init(); + SSL_load_error_strings(); + + if (use_tls_only) + meth = TLSv1_method(); else - fprintf( stderr, "%s: unexpected EOF\n", func ); + meth = SSLv23_method(); + + if (!meth) { + ssl_socket_perror("SSLv23_method"); + return -1; + } + + ctx = SSL_CTX_new(meth); + + if (verify) + SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER, NULL); + + if (!SSL_CTX_set_default_verify_paths(ctx)) { + ssl_socket_perror("SSL_CTX_set_default_verify_paths"); + return -1; + } + sock->ssl = SSL_new(ctx); + if (!sock->ssl) { + ssl_socket_perror("SSL_new"); + return -1; + } + if (!SSL_set_fd(sock->ssl, sock->fd)) { + ssl_socket_perror("SSL_set_fd"); + return -1; + } + + ret = SSL_connect(sock->ssl); + if (ret <= 0) { + socket_perror("SSL_connect", sock, ret); + return -1; + } + + return 0; +#endif } static int socket_read( Socket_t *sock, char *buf, int len ) { - ssize_t n = xread( sock->fd, buf, len ); + ssize_t n; +#ifndef NO_OPENSSL + if (sock->ssl) + n = SSL_read(sock->ssl, buf, len); + else +#endif + n = xread( sock->fd, buf, len ); if (n <= 0) { socket_perror( "read", sock, n ); close( sock->fd ); @@ -249,7 +342,13 @@ socket_read( Socket_t *sock, char *buf, int len ) static int socket_write( Socket_t *sock, const char *buf, int len ) { - int n = write_in_full( sock->fd, buf, len ); + int n; +#ifndef NO_OPENSSL + if (sock->ssl) + n = SSL_write(sock->ssl, buf, len); + else +#endif + n = write_in_full( sock->fd, buf, len ); if (n != len) { socket_perror( "write", sock, n ); close( sock->fd ); @@ -258,6 +357,17 @@ socket_write( Socket_t *sock, const char *buf, int len ) return n; } +static void socket_shutdown(Socket_t *sock) +{ +#ifndef NO_OPENSSL + if (sock->ssl) { + SSL_shutdown(sock->ssl); + SSL_free(sock->ssl); + } +#endif + close(sock->fd); +} + /* simple line buffering */ static int buffer_gets( buffer_t * b, char **s ) @@ -875,7 +985,7 @@ imap_close_server( imap_store_t *ictx ) if (imap->buf.sock.fd != -1) { imap_exec( ictx, NULL, "LOGOUT" ); - close( imap->buf.sock.fd ); + socket_shutdown( &imap->buf.sock ); } free_list( imap->ns_personal ); free_list( imap->ns_other ); @@ -906,6 +1016,7 @@ imap_open_store( imap_server_conf_t *srvc ) ctx->imap = imap = xcalloc( sizeof(*imap), 1 ); imap->buf.sock.fd = -1; + imap->buf.sock.ssl = NULL; imap->in_progress_append = &imap->in_progress; /* open connection to IMAP server */ @@ -958,10 +1069,15 @@ imap_open_store( imap_server_conf_t *srvc ) perror( "connect" ); goto bail; } - imap_info( "ok\n" ); - + imap->buf.sock.fd = s; + if (srvc->use_ssl && + ssl_socket_connect(&imap->buf.sock, 0, srvc->ssl_verify)) { + close(s); + goto bail; + } + imap_info( "ok\n" ); } /* read the greeting string */ @@ -986,7 +1102,18 @@ imap_open_store( imap_server_conf_t *srvc ) goto bail; if (!preauth) { - +#ifndef NO_OPENSSL + if (!srvc->use_ssl && CAP(STARTTLS)) { + if (imap_exec(ctx, 0, "STARTTLS") != RESP_OK) + goto bail; + if (ssl_socket_connect(&imap->buf.sock, 1, + srvc->ssl_verify)) + goto bail; + /* capabilities may have changed, so get the new capabilities */ + if (imap_exec(ctx, 0, "CAPABILITY") != RESP_OK) + goto bail; + } +#endif imap_info ("Logging in...\n"); if (!srvc->user) { fprintf( stderr, "Skipping server %s, no user\n", srvc->host ); @@ -1014,7 +1141,9 @@ imap_open_store( imap_server_conf_t *srvc ) fprintf( stderr, "Skipping account %s@%s, server forbids LOGIN\n", srvc->user, srvc->host ); goto bail; } - imap_warn( "*** IMAP Warning *** Password is being sent in the clear\n" ); + if (!imap->buf.sock.ssl) + imap_warn( "*** IMAP Warning *** Password is being " + "sent in the clear\n" ); if (imap_exec( ctx, NULL, "LOGIN \"%s\" \"%s\"", srvc->user, srvc->pass ) != RESP_OK) { fprintf( stderr, "IMAP error: LOGIN failed\n" ); goto bail; @@ -1242,6 +1371,8 @@ static imap_server_conf_t server = 0, /* port */ NULL, /* user */ NULL, /* pass */ + 0, /* use_ssl */ + 1, /* ssl_verify */ }; static char *imap_folder; @@ -1262,11 +1393,11 @@ git_imap_config(const char *key, const char *val, void *cb) if (!strcmp( "folder", key )) { imap_folder = xstrdup( val ); } else if (!strcmp( "host", key )) { - { - if (!prefixcmp(val, "imap:")) - val += 5; - if (!server.port) - server.port = 143; + if (!prefixcmp(val, "imap:")) + val += 5; + else if (!prefixcmp(val, "imaps:")) { + val += 6; + server.use_ssl = 1; } if (!prefixcmp(val, "//")) val += 2; @@ -1280,6 +1411,8 @@ git_imap_config(const char *key, const char *val, void *cb) server.port = git_config_int( key, val ); else if (!strcmp( "tunnel", key )) server.tunnel = xstrdup( val ); + else if (!strcmp( "ssl_verify", key )) + server.ssl_verify = git_config_bool( key, val ); return 0; } @@ -1299,6 +1432,9 @@ main(int argc, char **argv) setup_git_directory_gently( NULL ); git_config(git_imap_config, NULL); + if (!server.port) + server.port = server.use_ssl ? 993 : 143; + if (!imap_folder) { fprintf( stderr, "no imap store specified\n" ); return 1; -- 1.5.6.GIT ``` ## Junio C Hamano, 2008-07-08 23:20 Subject: Re: [PATCH 2/4] git-imap-send: Add support for SSL. Message-ID: <7vbq18q7yk.fsf@gitster.siamese.dyndns.org> URL: https://gitlist.dev/e/7vbq18q7yk.fsf%40gitster.siamese.dyndns.org In-Reply-To: <1215555496-21335-2-git-send-email-robertshearman@gmail.com> ``` Robert Shearman writes: > Allow SSL to be used when a imaps:// URL is used for the host name. > > Also, automatically use TLS when not using imaps:// by using the IMAP STARTTLS command, if the server supports it. > > Tested with Courier and Gimap IMAP servers. Sign-off? > diff --git a/Documentation/git-imap-send.txt b/Documentation/git-imap-send.txt > index b3d8da3..e4a5873 100644 > --- a/Documentation/git-imap-send.txt > +++ b/Documentation/git-imap-send.txt > @@ -37,10 +37,11 @@ configuration file (shown with examples): > Tunnel = "ssh -q user@server.com /usr/bin/imapd ./Maildir 2> /dev/null" > > [imap] > - Host = imap.server.com > + Host = imaps://imap.example.com > User = bob > Pass = pwd > - Port = 143 > + Port = 993 > + sslverify = false > .......................... Don't we also want to keep a vanilla configuration in the example, or is imaps the norm and unencrypted imap is exception these days? Don't we need to support custom certificates, keys and CAs, just like our code that supports https does, by honoring GIT_SSL_* environment variables and configuration file entries? The patch itself looks fairly clean, and I'd like to queue this for wider testing, initially even without GIT_SSL_* support. But I'd like to see any patch with substantial amount of changes properly signed off. Thanks. ``` ## Abhijit Menon-Sen, 2008-07-09 02:28 Subject: Re: [PATCH 2/4] git-imap-send: Add support for SSL. Message-ID: <20080709022839.GA4989@toroid.org> URL: https://gitlist.dev/e/20080709022839.GA4989%40toroid.org In-Reply-To: <7vbq18q7yk.fsf@gitster.siamese.dyndns.org> ``` At 2008-07-08 16:20:19 -0700, gitster@pobox.com wrote: > > > - Port = 143 > > + Port = 993 > > + sslverify = false > > .......................... > > Don't we also want to keep a vanilla configuration in the example, or > is imaps the norm and unencrypted imap is exception these days? The norm is IMAP+STARTTLS on port 143, not IMAPS on port 993. The latter is also widely deployed for compatibility with older clients, but it is non-standard and its use isn't exactly encouraged. -- ams ``` ## Rob Shearman, 2008-07-09 12:02 Subject: Re: [PATCH 2/4] git-imap-send: Add support for SSL. Message-ID: <1096648c0807090502x772fdaa4o59bf9932dc364de5@mail.gmail.com> URL: https://gitlist.dev/e/1096648c0807090502x772fdaa4o59bf9932dc364de5%40mail.gmail.com In-Reply-To: <7vbq18q7yk.fsf@gitster.siamese.dyndns.org> ``` 2008/7/9 Junio C Hamano : > Robert Shearman writes: >> diff --git a/Documentation/git-imap-send.txt b/Documentation/git-imap-send.txt >> index b3d8da3..e4a5873 100644 >> --- a/Documentation/git-imap-send.txt >> +++ b/Documentation/git-imap-send.txt >> @@ -37,10 +37,11 @@ configuration file (shown with examples): >> Tunnel = "ssh -q user@server.com /usr/bin/imapd ./Maildir 2> /dev/null" >> >> [imap] >> - Host = imap.server.com >> + Host = imaps://imap.example.com >> User = bob >> Pass = pwd >> - Port = 143 >> + Port = 993 >> + sslverify = false >> .......................... > > Don't we also want to keep a vanilla configuration in the example, or is > imaps the norm and unencrypted imap is exception these days? Good point. I'll fix the documentation to use imap:// instead of imaps:// and not change the port number. However, I'm not sure the examples should be telling the user what they should do, but rather what they can do. > Don't we need to support custom certificates, keys and CAs, just like our > code that supports https does, by honoring GIT_SSL_* environment variables > and configuration file entries? Yes, eventually we will want that support in imap-send too. It should be fairly trivial to do, although testing will be more difficult. > The patch itself looks fairly clean, and > I'd like to queue this for wider testing, initially even without GIT_SSL_* > support. But I'd like to see any patch with substantial amount of changes > properly signed off. Great. I'll resend the series later with changes from the comments I've received and properly signed-off. -- Rob Shearman ``` ## Josh Triplett, 2008-07-09 15:14 Subject: Re: [PATCH 2/4] git-imap-send: Add support for SSL. Message-ID: <1215616484.3053.6.camel@josh-work.beaverton.ibm.com> URL: https://gitlist.dev/e/1215616484.3053.6.camel%40josh-work.beaverton.ibm.com In-Reply-To: <1215555496-21335-2-git-send-email-robertshearman@gmail.com> ``` On Tue, 2008-07-08 at 23:18 +0100, Robert Shearman wrote: > --- a/Documentation/git-imap-send.txt > +++ b/Documentation/git-imap-send.txt > @@ -37,10 +37,11 @@ configuration file (shown with examples): > Tunnel = "ssh -q user@server.com /usr/bin/imapd ./Maildir 2> /dev/null" > > [imap] > - Host = imap.server.com > + Host = imaps://imap.example.com > User = bob > Pass = pwd > - Port = 143 > + Port = 993 > + sslverify = false [...] > @@ -1280,6 +1411,8 @@ git_imap_config(const char *key, const char *val, void *cb) > server.port = git_config_int( key, val ); > else if (!strcmp( "tunnel", key )) > server.tunnel = xstrdup( val ); > + else if (!strcmp( "ssl_verify", key )) > + server.ssl_verify = git_config_bool( key, val ); The example and the code disagree on the name of the sslverify/ssl_verify option. Also, ssl_verify needs explanation. - Josh Triplett ``` ## Junio C Hamano, 2008-07-09 18:28 Subject: Re: [PATCH 2/4] git-imap-send: Add support for SSL. Message-ID: <7vzloqkj38.fsf@gitster.siamese.dyndns.org> URL: https://gitlist.dev/e/7vzloqkj38.fsf%40gitster.siamese.dyndns.org In-Reply-To: <1096648c0807090502x772fdaa4o59bf9932dc364de5@mail.gmail.com> ``` "Rob Shearman" writes: > 2008/7/9 Junio C Hamano : > ... >> Don't we also want to keep a vanilla configuration in the example, or is >> imaps the norm and unencrypted imap is exception these days? > > Good point. I'll fix the documentation to use imap:// instead of > imaps:// and not change the port number. However, I'm not sure the > examples should be telling the user what they should do, but rather > what they can do. My comment was purely about losing the basic example by replacing it with something more advanced. Nobody prevents you from having _more_ examples. "You can do this, you can do that, also here is an example of how to use SSL". ``` ## Rob Shearman, 2008-07-09 21:24 Subject: Re: [PATCH 2/4] git-imap-send: Add support for SSL. Message-ID: <1096648c0807091424g1e10d0ccrae0be929ec428b89@mail.gmail.com> URL: https://gitlist.dev/e/1096648c0807091424g1e10d0ccrae0be929ec428b89%40mail.gmail.com In-Reply-To: <1215616484.3053.6.camel@josh-work.beaverton.ibm.com> ``` 2008/7/9 Josh Triplett : > On Tue, 2008-07-08 at 23:18 +0100, Robert Shearman wrote: >> --- a/Documentation/git-imap-send.txt >> +++ b/Documentation/git-imap-send.txt >> @@ -37,10 +37,11 @@ configuration file (shown with examples): >> Tunnel = "ssh -q user@server.com /usr/bin/imapd ./Maildir 2> /dev/null" >> >> [imap] >> - Host = imap.server.com >> + Host = imaps://imap.example.com >> User = bob >> Pass = pwd >> - Port = 143 >> + Port = 993 >> + sslverify = false > [...] >> @@ -1280,6 +1411,8 @@ git_imap_config(const char *key, const char *val, void *cb) >> server.port = git_config_int( key, val ); >> else if (!strcmp( "tunnel", key )) >> server.tunnel = xstrdup( val ); >> + else if (!strcmp( "ssl_verify", key )) >> + server.ssl_verify = git_config_bool( key, val ); > > The example and the code disagree on the name of the > sslverify/ssl_verify option. I wouldn't exactly call it "disagree". The config variable is limited by not allowing underscores, whereas the C language does allow them. > Also, ssl_verify needs explanation. See patch 4/4. -- Rob Shearman ``` ## Jeff King, 2008-07-10 06:39 Subject: Re: [PATCH 2/4] git-imap-send: Add support for SSL. Message-ID: <20080710063941.GC3195@sigill.intra.peff.net> URL: https://gitlist.dev/e/20080710063941.GC3195%40sigill.intra.peff.net In-Reply-To: <1096648c0807091424g1e10d0ccrae0be929ec428b89@mail.gmail.com> ``` On Wed, Jul 09, 2008 at 10:24:27PM +0100, Rob Shearman wrote: > >> [imap] > >> + sslverify = false > > [...] > >> + else if (!strcmp( "ssl_verify", key )) > > > > The example and the code disagree on the name of the > > sslverify/ssl_verify option. > > I wouldn't exactly call it "disagree". The config variable is limited > by not allowing underscores, whereas the C language does allow them. I think his point is that the example says "sslverify" but the code is looking for the config variable "ssl_verify". So that config won't work. However as you mention, underscore isn't allowed, so your strcmp line is totally bogus anyway, but you silently fix it in your 3/4 "style" fix. -Peff ```